drivers/usb/host/fotg210-hcd.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Faraday FOTG210 EHCI-like driver
   3  *
   4  * Copyright (c) 2013 Faraday Technology Corporation
   5  *
   6  * Author: Yuan-Hsin Chen <yhchen@faraday-tech.com>
   7  *         Feng-Hsin Chiang <john453@faraday-tech.com>
   8  *         Po-Yu Chuang <ratbert.chuang@gmail.com>
   9  *
  10  * Most of code borrowed from the Linux-3.7 EHCI driver
  11  */
  12 #include <linux/module.h>
  13 #include <linux/device.h>
  14 #include <linux/dmapool.h>
  15 #include <linux/kernel.h>
  16 #include <linux/delay.h>
  17 #include <linux/ioport.h>
  18 #include <linux/sched.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/errno.h>
  21 #include <linux/init.h>
  22 #include <linux/hrtimer.h>
  23 #include <linux/list.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/usb.h>
  26 #include <linux/usb/hcd.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/debugfs.h>
  30 #include <linux/slab.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/io.h>
  34
  35 #include <asm/byteorder.h>
  36 #include <asm/irq.h>
  37 #include <asm/unaligned.h>
  38
  39 #define DRIVER_AUTHOR "Yuan-Hsin Chen"
  40 #define DRIVER_DESC "FOTG210 Host Controller (EHCI) Driver"
  41 static const char hcd_name[] = "fotg210_hcd";
  42
  43 #undef FOTG210_URB_TRACE
  44 #define FOTG210_STATS
  45
  46 /* magic numbers that can affect system performance */
  47 #define FOTG210_TUNE_CERR       3 /* 0-3 qtd retries; 0 == don't stop */
  48 #define FOTG210_TUNE_RL_HS      4 /* nak throttle; see 4.9 */
  49 #define FOTG210_TUNE_RL_TT      0
  50 #define FOTG210_TUNE_MULT_HS    1 /* 1-3 transactions/uframe; 4.10.3 */
  51 #define FOTG210_TUNE_MULT_TT    1
  52
  53 /* Some drivers think it's safe to schedule isochronous transfers more than 256
  54  * ms into the future (partly as a result of an old bug in the scheduling
  55  * code).  In an attempt to avoid trouble, we will use a minimum scheduling
  56  * length of 512 frames instead of 256.
  57  */
  58 #define FOTG210_TUNE_FLS 1 /* (medium) 512-frame schedule */
  59
  60 /* Initial IRQ latency:  faster than hw default */
  61 static int log2_irq_thresh; /* 0 to 6 */
  62 module_param(log2_irq_thresh, int, S_IRUGO);
  63 MODULE_PARM_DESC(log2_irq_thresh, "log2 IRQ latency, 1-64 microframes");
  64
  65 /* initial park setting:  slower than hw default */
  66 static unsigned park;
  67 module_param(park, uint, S_IRUGO);
  68 MODULE_PARM_DESC(park, "park setting; 1-3 back-to-back async packets");
  69
  70 /* for link power management(LPM) feature */
  71 static unsigned int hird;
  72 module_param(hird, int, S_IRUGO);
  73 MODULE_PARM_DESC(hird, "host initiated resume duration, +1 for each 75us");
  74
  75 #define INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)
  76
  77 #include "fotg210.h"
  78
  79 #define fotg210_dbg(fotg210, fmt, args...) \
  80         dev_dbg(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  81 #define fotg210_err(fotg210, fmt, args...) \
  82         dev_err(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  83 #define fotg210_info(fotg210, fmt, args...) \
  84         dev_info(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  85 #define fotg210_warn(fotg210, fmt, args...) \
  86         dev_warn(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  87
  88 /* check the values in the HCSPARAMS register (host controller _Structural_
  89  * parameters) see EHCI spec, Table 2-4 for each value
  90  */
  91 static void dbg_hcs_params(struct fotg210_hcd *fotg210, char *label)
  92 {
  93         u32 params = fotg210_readl(fotg210, &fotg210->caps->hcs_params);
  94
  95         fotg210_dbg(fotg210, "%s hcs_params 0x%x ports=%d\n", label, params,
  96                         HCS_N_PORTS(params));
  97 }
  98
  99 /* check the values in the HCCPARAMS register (host controller _Capability_
 100  * parameters) see EHCI Spec, Table 2-5 for each value
 101  */
 102 static void dbg_hcc_params(struct fotg210_hcd *fotg210, char *label)
 103 {
 104         u32 params = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
 105
 106         fotg210_dbg(fotg210, "%s hcc_params %04x uframes %s%s\n", label,
 107                         params,
 108                         HCC_PGM_FRAMELISTLEN(params) ? "256/512/1024" : "1024",
 109                         HCC_CANPARK(params) ? " park" : "");
 110 }
 111
 112 static void __maybe_unused
 113 dbg_qtd(const char *label, struct fotg210_hcd *fotg210, struct fotg210_qtd *qtd)
 114 {
 115         fotg210_dbg(fotg210, "%s td %p n%08x %08x t%08x p0=%08x\n", label, qtd,
 116                         hc32_to_cpup(fotg210, &qtd->hw_next),
 117                         hc32_to_cpup(fotg210, &qtd->hw_alt_next),
 118                         hc32_to_cpup(fotg210, &qtd->hw_token),
 119                         hc32_to_cpup(fotg210, &qtd->hw_buf[0]));
 120         if (qtd->hw_buf[1])
 121                 fotg210_dbg(fotg210, "  p1=%08x p2=%08x p3=%08x p4=%08x\n",
 122                                 hc32_to_cpup(fotg210, &qtd->hw_buf[1]),
 123                                 hc32_to_cpup(fotg210, &qtd->hw_buf[2]),
 124                                 hc32_to_cpup(fotg210, &qtd->hw_buf[3]),
 125                                 hc32_to_cpup(fotg210, &qtd->hw_buf[4]));
 126 }
 127
 128 static void __maybe_unused
 129 dbg_qh(const char *label, struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
 130 {
 131         struct fotg210_qh_hw *hw = qh->hw;
 132
 133         fotg210_dbg(fotg210, "%s qh %p n%08x info %x %x qtd %x\n", label, qh,
 134                         hw->hw_next, hw->hw_info1, hw->hw_info2,
 135                         hw->hw_current);
 136
 137         dbg_qtd("overlay", fotg210, (struct fotg210_qtd *) &hw->hw_qtd_next);
 138 }
 139
 140 static void __maybe_unused
 141 dbg_itd(const char *label, struct fotg210_hcd *fotg210, struct fotg210_itd *itd)
 142 {
 143         fotg210_dbg(fotg210, "%s[%d] itd %p, next %08x, urb %p\n", label,
 144                         itd->frame, itd, hc32_to_cpu(fotg210, itd->hw_next),
 145                         itd->urb);
 146
 147         fotg210_dbg(fotg210,
 148                         "  trans: %08x %08x %08x %08x %08x %08x %08x %08x\n",
 149                         hc32_to_cpu(fotg210, itd->hw_transaction[0]),
 150                         hc32_to_cpu(fotg210, itd->hw_transaction[1]),
 151                         hc32_to_cpu(fotg210, itd->hw_transaction[2]),
 152                         hc32_to_cpu(fotg210, itd->hw_transaction[3]),
 153                         hc32_to_cpu(fotg210, itd->hw_transaction[4]),
 154                         hc32_to_cpu(fotg210, itd->hw_transaction[5]),
 155                         hc32_to_cpu(fotg210, itd->hw_transaction[6]),
 156                         hc32_to_cpu(fotg210, itd->hw_transaction[7]));
 157
 158         fotg210_dbg(fotg210,
 159                         "  buf:   %08x %08x %08x %08x %08x %08x %08x\n",
 160                         hc32_to_cpu(fotg210, itd->hw_bufp[0]),
 161                         hc32_to_cpu(fotg210, itd->hw_bufp[1]),
 162                         hc32_to_cpu(fotg210, itd->hw_bufp[2]),
 163                         hc32_to_cpu(fotg210, itd->hw_bufp[3]),
 164                         hc32_to_cpu(fotg210, itd->hw_bufp[4]),
 165                         hc32_to_cpu(fotg210, itd->hw_bufp[5]),
 166                         hc32_to_cpu(fotg210, itd->hw_bufp[6]));
 167
 168         fotg210_dbg(fotg210, "  index: %d %d %d %d %d %d %d %d\n",
 169                         itd->index[0], itd->index[1], itd->index[2],
 170                         itd->index[3], itd->index[4], itd->index[5],
 171                         itd->index[6], itd->index[7]);
 172 }
 173
 174 static int __maybe_unused
 175 dbg_status_buf(char *buf, unsigned len, const char *label, u32 status)
 176 {
 177         return scnprintf(buf, len, "%s%sstatus %04x%s%s%s%s%s%s%s%s%s%s",
 178                         label, label[0] ? " " : "", status,
 179                         (status & STS_ASS) ? " Async" : "",
 180                         (status & STS_PSS) ? " Periodic" : "",
 181                         (status & STS_RECL) ? " Recl" : "",
 182                         (status & STS_HALT) ? " Halt" : "",
 183                         (status & STS_IAA) ? " IAA" : "",
 184                         (status & STS_FATAL) ? " FATAL" : "",
 185                         (status & STS_FLR) ? " FLR" : "",
 186                         (status & STS_PCD) ? " PCD" : "",
 187                         (status & STS_ERR) ? " ERR" : "",
 188                         (status & STS_INT) ? " INT" : "");
 189 }
 190
 191 static int __maybe_unused
 192 dbg_intr_buf(char *buf, unsigned len, const char *label, u32 enable)
 193 {
 194         return scnprintf(buf, len, "%s%sintrenable %02x%s%s%s%s%s%s",
 195                         label, label[0] ? " " : "", enable,
 196                         (enable & STS_IAA) ? " IAA" : "",
 197                         (enable & STS_FATAL) ? " FATAL" : "",
 198                         (enable & STS_FLR) ? " FLR" : "",
 199                         (enable & STS_PCD) ? " PCD" : "",
 200                         (enable & STS_ERR) ? " ERR" : "",
 201                         (enable & STS_INT) ? " INT" : "");
 202 }
 203
 204 static const char *const fls_strings[] = { "1024", "512", "256", "??" };
 205
 206 static int dbg_command_buf(char *buf, unsigned len, const char *label,
 207                 u32 command)
 208 {
 209         return scnprintf(buf, len,
 210                         "%s%scommand %07x %s=%d ithresh=%d%s%s%s period=%s%s %s",
 211                         label, label[0] ? " " : "", command,
 212                         (command & CMD_PARK) ? " park" : "(park)",
 213                         CMD_PARK_CNT(command),
 214                         (command >> 16) & 0x3f,
 215                         (command & CMD_IAAD) ? " IAAD" : "",
 216                         (command & CMD_ASE) ? " Async" : "",
 217                         (command & CMD_PSE) ? " Periodic" : "",
 218                         fls_strings[(command >> 2) & 0x3],
 219                         (command & CMD_RESET) ? " Reset" : "",
 220                         (command & CMD_RUN) ? "RUN" : "HALT");
 221 }
 222
 223 static char *dbg_port_buf(char *buf, unsigned len, const char *label, int port,
 224                 u32 status)
 225 {
 226         char *sig;
 227
 228         /* signaling state */
 229         switch (status & (3 << 10)) {
 230         case 0 << 10:
 231                 sig = "se0";
 232                 break;
 233         case 1 << 10:
 234                 sig = "k";
 235                 break; /* low speed */
 236         case 2 << 10:
 237                 sig = "j";
 238                 break;
 239         default:
 240                 sig = "?";
 241                 break;
 242         }
 243
 244         scnprintf(buf, len, "%s%sport:%d status %06x %d sig=%s%s%s%s%s%s%s%s",
 245                         label, label[0] ? " " : "", port, status,
 246                         status >> 25, /*device address */
 247                         sig,
 248                         (status & PORT_RESET) ? " RESET" : "",
 249                         (status & PORT_SUSPEND) ? " SUSPEND" : "",
 250                         (status & PORT_RESUME) ? " RESUME" : "",
 251                         (status & PORT_PEC) ? " PEC" : "",
 252                         (status & PORT_PE) ? " PE" : "",
 253                         (status & PORT_CSC) ? " CSC" : "",
 254                         (status & PORT_CONNECT) ? " CONNECT" : "");
 255
 256         return buf;
 257 }
 258
 259 /* functions have the "wrong" filename when they're output... */
 260 #define dbg_status(fotg210, label, status) {                    \
 261         char _buf[80];                                          \
 262         dbg_status_buf(_buf, sizeof(_buf), label, status);      \
 263         fotg210_dbg(fotg210, "%s\n", _buf);                     \
 264 }
 265
 266 #define dbg_cmd(fotg210, label, command) {                      \
 267         char _buf[80];                                          \
 268         dbg_command_buf(_buf, sizeof(_buf), label, command);    \
 269         fotg210_dbg(fotg210, "%s\n", _buf);                     \
 270 }
 271
 272 #define dbg_port(fotg210, label, port, status) {                               \
 273         char _buf[80];                                                         \
 274         fotg210_dbg(fotg210, "%s\n",                                           \
 275                         dbg_port_buf(_buf, sizeof(_buf), label, port, status));\
 276 }
 277
 278 /* troubleshooting help: expose state in debugfs */
 279 static int debug_async_open(struct inode *, struct file *);
 280 static int debug_periodic_open(struct inode *, struct file *);
 281 static int debug_registers_open(struct inode *, struct file *);
 282 static int debug_async_open(struct inode *, struct file *);
 283
 284 static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
 285 static int debug_close(struct inode *, struct file *);
 286
 287 static const struct file_operations debug_async_fops = {
 288         .owner          = THIS_MODULE,
 289         .open           = debug_async_open,
 290         .read           = debug_output,
 291         .release        = debug_close,
 292         .llseek         = default_llseek,
 293 };
 294 static const struct file_operations debug_periodic_fops = {
 295         .owner          = THIS_MODULE,
 296         .open           = debug_periodic_open,
 297         .read           = debug_output,
 298         .release        = debug_close,
 299         .llseek         = default_llseek,
 300 };
 301 static const struct file_operations debug_registers_fops = {
 302         .owner          = THIS_MODULE,
 303         .open           = debug_registers_open,
 304         .read           = debug_output,
 305         .release        = debug_close,
 306         .llseek         = default_llseek,
 307 };
 308
 309 static struct dentry *fotg210_debug_root;
 310
 311 struct debug_buffer {
 312         ssize_t (*fill_func)(struct debug_buffer *);    /* fill method */
 313         struct usb_bus *bus;
 314         struct mutex mutex;     /* protect filling of buffer */
 315         size_t count;           /* number of characters filled into buffer */
 316         char *output_buf;
 317         size_t alloc_size;
 318 };
 319
 320 static inline char speed_char(u32 scratch)
 321 {
 322         switch (scratch & (3 << 12)) {
 323         case QH_FULL_SPEED:
 324                 return 'f';
 325
 326         case QH_LOW_SPEED:
 327                 return 'l';
 328
 329         case QH_HIGH_SPEED:
 330                 return 'h';
 331
 332         default:
 333                 return '?';
 334         }
 335 }
 336
 337 static inline char token_mark(struct fotg210_hcd *fotg210, __hc32 token)
 338 {
 339         __u32 v = hc32_to_cpu(fotg210, token);
 340
 341         if (v & QTD_STS_ACTIVE)
 342                 return '*';
 343         if (v & QTD_STS_HALT)
 344                 return '-';
 345         if (!IS_SHORT_READ(v))
 346                 return ' ';
 347         /* tries to advance through hw_alt_next */
 348         return '/';
 349 }
 350
 351 static void qh_lines(struct fotg210_hcd *fotg210, struct fotg210_qh *qh,
 352                 char **nextp, unsigned *sizep)
 353 {
 354         u32 scratch;
 355         u32 hw_curr;
 356         struct fotg210_qtd *td;
 357         unsigned temp;
 358         unsigned size = *sizep;
 359         char *next = *nextp;
 360         char mark;
 361         __le32 list_end = FOTG210_LIST_END(fotg210);
 362         struct fotg210_qh_hw *hw = qh->hw;
 363
 364         if (hw->hw_qtd_next == list_end) /* NEC does this */
 365                 mark = '@';
 366         else
 367                 mark = token_mark(fotg210, hw->hw_token);
 368         if (mark == '/') { /* qh_alt_next controls qh advance? */
 369                 if ((hw->hw_alt_next & QTD_MASK(fotg210)) ==
 370                     fotg210->async->hw->hw_alt_next)
 371                         mark = '#'; /* blocked */
 372                 else if (hw->hw_alt_next == list_end)
 373                         mark = '.'; /* use hw_qtd_next */
 374                 /* else alt_next points to some other qtd */
 375         }
 376         scratch = hc32_to_cpup(fotg210, &hw->hw_info1);
 377         hw_curr = (mark == '*') ? hc32_to_cpup(fotg210, &hw->hw_current) : 0;
 378         temp = scnprintf(next, size,
 379                         "qh/%p dev%d %cs ep%d %08x %08x(%08x%c %s nak%d)",
 380                         qh, scratch & 0x007f,
 381                         speed_char(scratch),
 382                         (scratch >> 8) & 0x000f,
 383                         scratch, hc32_to_cpup(fotg210, &hw->hw_info2),
 384                         hc32_to_cpup(fotg210, &hw->hw_token), mark,
 385                         (cpu_to_hc32(fotg210, QTD_TOGGLE) & hw->hw_token)
 386                                 ? "data1" : "data0",
 387                         (hc32_to_cpup(fotg210, &hw->hw_alt_next) >> 1) & 0x0f);
 388         size -= temp;
 389         next += temp;
 390
 391         /* hc may be modifying the list as we read it ... */
 392         list_for_each_entry(td, &qh->qtd_list, qtd_list) {
 393                 scratch = hc32_to_cpup(fotg210, &td->hw_token);
 394                 mark = ' ';
 395                 if (hw_curr == td->qtd_dma)
 396                         mark = '*';
 397                 else if (hw->hw_qtd_next == cpu_to_hc32(fotg210, td->qtd_dma))
 398                         mark = '+';
 399                 else if (QTD_LENGTH(scratch)) {
 400                         if (td->hw_alt_next == fotg210->async->hw->hw_alt_next)
 401                                 mark = '#';
 402                         else if (td->hw_alt_next != list_end)
 403                                 mark = '/';
 404                 }
 405                 temp = snprintf(next, size,
 406                                 "\n\t%p%c%s len=%d %08x urb %p",
 407                                 td, mark, ({ char *tmp;
 408                                  switch ((scratch>>8)&0x03) {
 409                                  case 0:
 410                                         tmp = "out";
 411                                         break;
 412                                  case 1:
 413                                         tmp = "in";
 414                                         break;
 415                                  case 2:
 416                                         tmp = "setup";
 417                                         break;
 418                                  default:
 419                                         tmp = "?";
 420                                         break;
 421                                  } tmp; }),
 422                                 (scratch >> 16) & 0x7fff,
 423                                 scratch,
 424                                 td->urb);
 425                 if (size < temp)
 426                         temp = size;
 427                 size -= temp;
 428                 next += temp;
 429                 if (temp == size)
 430                         goto done;
 431         }
 432
 433         temp = snprintf(next, size, "\n");
 434         if (size < temp)
 435                 temp = size;
 436
 437         size -= temp;
 438         next += temp;
 439
 440 done:
 441         *sizep = size;
 442         *nextp = next;
 443 }
 444
 445 static ssize_t fill_async_buffer(struct debug_buffer *buf)
 446 {
 447         struct usb_hcd *hcd;
 448         struct fotg210_hcd *fotg210;
 449         unsigned long flags;
 450         unsigned temp, size;
 451         char *next;
 452         struct fotg210_qh *qh;
 453
 454         hcd = bus_to_hcd(buf->bus);
 455         fotg210 = hcd_to_fotg210(hcd);
 456         next = buf->output_buf;
 457         size = buf->alloc_size;
 458
 459         *next = 0;
 460
 461         /* dumps a snapshot of the async schedule.
 462          * usually empty except for long-term bulk reads, or head.
 463          * one QH per line, and TDs we know about
 464          */
 465         spin_lock_irqsave(&fotg210->lock, flags);
 466         for (qh = fotg210->async->qh_next.qh; size > 0 && qh;
 467                         qh = qh->qh_next.qh)
 468                 qh_lines(fotg210, qh, &next, &size);
 469         if (fotg210->async_unlink && size > 0) {
 470                 temp = scnprintf(next, size, "\nunlink =\n");
 471                 size -= temp;
 472                 next += temp;
 473
 474                 for (qh = fotg210->async_unlink; size > 0 && qh;
 475                                 qh = qh->unlink_next)
 476                         qh_lines(fotg210, qh, &next, &size);
 477         }
 478         spin_unlock_irqrestore(&fotg210->lock, flags);
 479
 480         return strlen(buf->output_buf);
 481 }
 482
 483 /* count tds, get ep direction */
 484 static unsigned output_buf_tds_dir(char *buf, struct fotg210_hcd *fotg210,
 485                 struct fotg210_qh_hw *hw, struct fotg210_qh *qh, unsigned size)
 486 {
 487         u32 scratch = hc32_to_cpup(fotg210, &hw->hw_info1);
 488         struct fotg210_qtd *qtd;
 489         char *type = "";
 490         unsigned temp = 0;
 491
 492         /* count tds, get ep direction */
 493         list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
 494                 temp++;
 495                 switch ((hc32_to_cpu(fotg210, qtd->hw_token) >> 8) & 0x03) {
 496                 case 0:
 497                         type = "out";
 498                         continue;
 499                 case 1:
 500                         type = "in";
 501                         continue;
 502                 }
 503         }
 504
 505         return scnprintf(buf, size, "(%c%d ep%d%s [%d/%d] q%d p%d)",
 506                         speed_char(scratch), scratch & 0x007f,
 507                         (scratch >> 8) & 0x000f, type, qh->usecs,
 508                         qh->c_usecs, temp, (scratch >> 16) & 0x7ff);
 509 }
 510
 511 #define DBG_SCHED_LIMIT 64
 512 static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
 513 {
 514         struct usb_hcd *hcd;
 515         struct fotg210_hcd *fotg210;
 516         unsigned long flags;
 517         union fotg210_shadow p, *seen;
 518         unsigned temp, size, seen_count;
 519         char *next;
 520         unsigned i;
 521         __hc32 tag;
 522
 523         seen = kmalloc_array(DBG_SCHED_LIMIT, sizeof(*seen), GFP_ATOMIC);
 524         if (!seen)
 525                 return 0;
 526
 527         seen_count = 0;
 528
 529         hcd = bus_to_hcd(buf->bus);
 530         fotg210 = hcd_to_fotg210(hcd);
 531         next = buf->output_buf;
 532         size = buf->alloc_size;
 533
 534         temp = scnprintf(next, size, "size = %d\n", fotg210->periodic_size);
 535         size -= temp;
 536         next += temp;
 537
 538         /* dump a snapshot of the periodic schedule.
 539          * iso changes, interrupt usually doesn't.
 540          */
 541         spin_lock_irqsave(&fotg210->lock, flags);
 542         for (i = 0; i < fotg210->periodic_size; i++) {
 543                 p = fotg210->pshadow[i];
 544                 if (likely(!p.ptr))
 545                         continue;
 546
 547                 tag = Q_NEXT_TYPE(fotg210, fotg210->periodic[i]);
 548
 549                 temp = scnprintf(next, size, "%4d: ", i);
 550                 size -= temp;
 551                 next += temp;
 552
 553                 do {
 554                         struct fotg210_qh_hw *hw;
 555
 556                         switch (hc32_to_cpu(fotg210, tag)) {
 557                         case Q_TYPE_QH:
 558                                 hw = p.qh->hw;
 559                                 temp = scnprintf(next, size, " qh%d-%04x/%p",
 560                                                 p.qh->period,
 561                                                 hc32_to_cpup(fotg210,
 562                                                         &hw->hw_info2)
 563                                                         /* uframe masks */
 564                                                         & (QH_CMASK | QH_SMASK),
 565                                                 p.qh);
 566                                 size -= temp;
 567                                 next += temp;
 568                                 /* don't repeat what follows this qh */
 569                                 for (temp = 0; temp < seen_count; temp++) {
 570                                         if (seen[temp].ptr != p.ptr)
 571                                                 continue;
 572                                         if (p.qh->qh_next.ptr) {
 573                                                 temp = scnprintf(next, size,
 574                                                                 " ...");
 575                                                 size -= temp;
 576                                                 next += temp;
 577                                         }
 578                                         break;
 579                                 }
 580                                 /* show more info the first time around */
 581                                 if (temp == seen_count) {
 582                                         temp = output_buf_tds_dir(next,
 583                                                         fotg210, hw,
 584                                                         p.qh, size);
 585
 586                                         if (seen_count < DBG_SCHED_LIMIT)
 587                                                 seen[seen_count++].qh = p.qh;
 588                                 } else
 589                                         temp = 0;
 590                                 tag = Q_NEXT_TYPE(fotg210, hw->hw_next);
 591                                 p = p.qh->qh_next;
 592                                 break;
 593                         case Q_TYPE_FSTN:
 594                                 temp = scnprintf(next, size,
 595                                                 " fstn-%8x/%p",
 596                                                 p.fstn->hw_prev, p.fstn);
 597                                 tag = Q_NEXT_TYPE(fotg210, p.fstn->hw_next);
 598                                 p = p.fstn->fstn_next;
 599                                 break;
 600                         case Q_TYPE_ITD:
 601                                 temp = scnprintf(next, size,
 602                                                 " itd/%p", p.itd);
 603                                 tag = Q_NEXT_TYPE(fotg210, p.itd->hw_next);
 604                                 p = p.itd->itd_next;
 605                                 break;
 606                         }
 607                         size -= temp;
 608                         next += temp;
 609                 } while (p.ptr);
 610
 611                 temp = scnprintf(next, size, "\n");
 612                 size -= temp;
 613                 next += temp;
 614         }
 615         spin_unlock_irqrestore(&fotg210->lock, flags);
 616         kfree(seen);
 617
 618         return buf->alloc_size - size;
 619 }
 620 #undef DBG_SCHED_LIMIT
 621
 622 static const char *rh_state_string(struct fotg210_hcd *fotg210)
 623 {
 624         switch (fotg210->rh_state) {
 625         case FOTG210_RH_HALTED:
 626                 return "halted";
 627         case FOTG210_RH_SUSPENDED:
 628                 return "suspended";
 629         case FOTG210_RH_RUNNING:
 630                 return "running";
 631         case FOTG210_RH_STOPPING:
 632                 return "stopping";
 633         }
 634         return "?";
 635 }
 636
 637 static ssize_t fill_registers_buffer(struct debug_buffer *buf)
 638 {
 639         struct usb_hcd *hcd;
 640         struct fotg210_hcd *fotg210;
 641         unsigned long flags;
 642         unsigned temp, size, i;
 643         char *next, scratch[80];
 644         static const char fmt[] = "%*s\n";
 645         static const char label[] = "";
 646
 647         hcd = bus_to_hcd(buf->bus);
 648         fotg210 = hcd_to_fotg210(hcd);
 649         next = buf->output_buf;
 650         size = buf->alloc_size;
 651
 652         spin_lock_irqsave(&fotg210->lock, flags);
 653
 654         if (!HCD_HW_ACCESSIBLE(hcd)) {
 655                 size = scnprintf(next, size,
 656                                 "bus %s, device %s\n"
 657                                 "%s\n"
 658                                 "SUSPENDED(no register access)\n",
 659                                 hcd->self.controller->bus->name,
 660                                 dev_name(hcd->self.controller),
 661                                 hcd->product_desc);
 662                 goto done;
 663         }
 664
 665         /* Capability Registers */
 666         i = HC_VERSION(fotg210, fotg210_readl(fotg210,
 667                         &fotg210->caps->hc_capbase));
 668         temp = scnprintf(next, size,
 669                         "bus %s, device %s\n"
 670                         "%s\n"
 671                         "EHCI %x.%02x, rh state %s\n",
 672                         hcd->self.controller->bus->name,
 673                         dev_name(hcd->self.controller),
 674                         hcd->product_desc,
 675                         i >> 8, i & 0x0ff, rh_state_string(fotg210));
 676         size -= temp;
 677         next += temp;
 678
 679         /* FIXME interpret both types of params */
 680         i = fotg210_readl(fotg210, &fotg210->caps->hcs_params);
 681         temp = scnprintf(next, size, "structural params 0x%08x\n", i);
 682         size -= temp;
 683         next += temp;
 684
 685         i = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
 686         temp = scnprintf(next, size, "capability params 0x%08x\n", i);
 687         size -= temp;
 688         next += temp;
 689
 690         /* Operational Registers */
 691         temp = dbg_status_buf(scratch, sizeof(scratch), label,
 692                         fotg210_readl(fotg210, &fotg210->regs->status));
 693         temp = scnprintf(next, size, fmt, temp, scratch);
 694         size -= temp;
 695         next += temp;
 696
 697         temp = dbg_command_buf(scratch, sizeof(scratch), label,
 698                         fotg210_readl(fotg210, &fotg210->regs->command));
 699         temp = scnprintf(next, size, fmt, temp, scratch);
 700         size -= temp;
 701         next += temp;
 702
 703         temp = dbg_intr_buf(scratch, sizeof(scratch), label,
 704                         fotg210_readl(fotg210, &fotg210->regs->intr_enable));
 705         temp = scnprintf(next, size, fmt, temp, scratch);
 706         size -= temp;
 707         next += temp;
 708
 709         temp = scnprintf(next, size, "uframe %04x\n",
 710                         fotg210_read_frame_index(fotg210));
 711         size -= temp;
 712         next += temp;
 713
 714         if (fotg210->async_unlink) {
 715                 temp = scnprintf(next, size, "async unlink qh %p\n",
 716                                 fotg210->async_unlink);
 717                 size -= temp;
 718                 next += temp;
 719         }
 720
 721 #ifdef FOTG210_STATS
 722         temp = scnprintf(next, size,
 723                         "irq normal %ld err %ld iaa %ld(lost %ld)\n",
 724                         fotg210->stats.normal, fotg210->stats.error,
 725                         fotg210->stats.iaa, fotg210->stats.lost_iaa);
 726         size -= temp;
 727         next += temp;
 728
 729         temp = scnprintf(next, size, "complete %ld unlink %ld\n",
 730                         fotg210->stats.complete, fotg210->stats.unlink);
 731         size -= temp;
 732         next += temp;
 733 #endif
 734
 735 done:
 736         spin_unlock_irqrestore(&fotg210->lock, flags);
 737
 738         return buf->alloc_size - size;
 739 }
 740
 741 static struct debug_buffer
 742 *alloc_buffer(struct usb_bus *bus, ssize_t (*fill_func)(struct debug_buffer *))
 743 {
 744         struct debug_buffer *buf;
 745
 746         buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
 747
 748         if (buf) {
 749                 buf->bus = bus;
 750                 buf->fill_func = fill_func;
 751                 mutex_init(&buf->mutex);
 752                 buf->alloc_size = PAGE_SIZE;
 753         }
 754
 755         return buf;
 756 }
 757
 758 static int fill_buffer(struct debug_buffer *buf)
 759 {
 760         int ret = 0;
 761
 762         if (!buf->output_buf)
 763                 buf->output_buf = vmalloc(buf->alloc_size);
 764
 765         if (!buf->output_buf) {
 766                 ret = -ENOMEM;
 767                 goto out;
 768         }
 769
 770         ret = buf->fill_func(buf);
 771
 772         if (ret >= 0) {
 773                 buf->count = ret;
 774                 ret = 0;
 775         }
 776
 777 out:
 778         return ret;
 779 }
 780
 781 static ssize_t debug_output(struct file *file, char __user *user_buf,
 782                 size_t len, loff_t *offset)
 783 {
 784         struct debug_buffer *buf = file->private_data;
 785         int ret = 0;
 786
 787         mutex_lock(&buf->mutex);
 788         if (buf->count == 0) {
 789                 ret = fill_buffer(buf);
 790                 if (ret != 0) {
 791                         mutex_unlock(&buf->mutex);
 792                         goto out;
 793                 }
 794         }
 795         mutex_unlock(&buf->mutex);
 796
 797         ret = simple_read_from_buffer(user_buf, len, offset,
 798                         buf->output_buf, buf->count);
 799
 800 out:
 801         return ret;
 802
 803 }
 804
 805 static int debug_close(struct inode *inode, struct file *file)
 806 {
 807         struct debug_buffer *buf = file->private_data;
 808
 809         if (buf) {
 810                 vfree(buf->output_buf);
 811                 kfree(buf);
 812         }
 813
 814         return 0;
 815 }
 816 static int debug_async_open(struct inode *inode, struct file *file)
 817 {
 818         file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
 819
 820         return file->private_data ? 0 : -ENOMEM;
 821 }
 822
 823 static int debug_periodic_open(struct inode *inode, struct file *file)
 824 {
 825         struct debug_buffer *buf;
 826
 827         buf = alloc_buffer(inode->i_private, fill_periodic_buffer);
 828         if (!buf)
 829                 return -ENOMEM;
 830
 831         buf->alloc_size = (sizeof(void *) == 4 ? 6 : 8)*PAGE_SIZE;
 832         file->private_data = buf;
 833         return 0;
 834 }
 835
 836 static int debug_registers_open(struct inode *inode, struct file *file)
 837 {
 838         file->private_data = alloc_buffer(inode->i_private,
 839                         fill_registers_buffer);
 840
 841         return file->private_data ? 0 : -ENOMEM;
 842 }
 843
 844 static inline void create_debug_files(struct fotg210_hcd *fotg210)
 845 {
 846         struct usb_bus *bus = &fotg210_to_hcd(fotg210)->self;
 847         struct dentry *root;
 848
 849         root = debugfs_create_dir(bus->bus_name, fotg210_debug_root);
 850         fotg210->debug_dir = root;
 851
 852         debugfs_create_file("async", S_IRUGO, root, bus, &debug_async_fops);
 853         debugfs_create_file("periodic", S_IRUGO, root, bus,
 854                             &debug_periodic_fops);
 855         debugfs_create_file("registers", S_IRUGO, root, bus,
 856                             &debug_registers_fops);
 857 }
 858
 859 static inline void remove_debug_files(struct fotg210_hcd *fotg210)
 860 {
 861         debugfs_remove_recursive(fotg210->debug_dir);
 862 }
 863
 864 /* handshake - spin reading hc until handshake completes or fails
 865  * @ptr: address of hc register to be read
 866  * @mask: bits to look at in result of read
 867  * @done: value of those bits when handshake succeeds
 868  * @usec: timeout in microseconds
 869  *
 870  * Returns negative errno, or zero on success
 871  *
 872  * Success happens when the "mask" bits have the specified value (hardware
 873  * handshake done).  There are two failure modes:  "usec" have passed (major
 874  * hardware flakeout), or the register reads as all-ones (hardware removed).
 875  *
 876  * That last failure should_only happen in cases like physical cardbus eject
 877  * before driver shutdown. But it also seems to be caused by bugs in cardbus
 878  * bridge shutdown:  shutting down the bridge before the devices using it.
 879  */
 880 static int handshake(struct fotg210_hcd *fotg210, void __iomem *ptr,
 881                 u32 mask, u32 done, int usec)
 882 {
 883         u32 result;
 884
 885         do {
 886                 result = fotg210_readl(fotg210, ptr);
 887                 if (result == ~(u32)0)          /* card removed */
 888                         return -ENODEV;
 889                 result &= mask;
 890                 if (result == done)
 891                         return 0;
 892                 udelay(1);
 893                 usec--;
 894         } while (usec > 0);
 895         return -ETIMEDOUT;
 896 }
 897
 898 /* Force HC to halt state from unknown (EHCI spec section 2.3).
 899  * Must be called with interrupts enabled and the lock not held.
 900  */
 901 static int fotg210_halt(struct fotg210_hcd *fotg210)
 902 {
 903         u32 temp;
 904
 905         spin_lock_irq(&fotg210->lock);
 906
 907         /* disable any irqs left enabled by previous code */
 908         fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
 909
 910         /*
 911          * This routine gets called during probe before fotg210->command
 912          * has been initialized, so we can't rely on its value.
 913          */
 914         fotg210->command &= ~CMD_RUN;
 915         temp = fotg210_readl(fotg210, &fotg210->regs->command);
 916         temp &= ~(CMD_RUN | CMD_IAAD);
 917         fotg210_writel(fotg210, temp, &fotg210->regs->command);
 918
 919         spin_unlock_irq(&fotg210->lock);
 920         synchronize_irq(fotg210_to_hcd(fotg210)->irq);
 921
 922         return handshake(fotg210, &fotg210->regs->status,
 923                         STS_HALT, STS_HALT, 16 * 125);
 924 }
 925
 926 /* Reset a non-running (STS_HALT == 1) controller.
 927  * Must be called with interrupts enabled and the lock not held.
 928  */
 929 static int fotg210_reset(struct fotg210_hcd *fotg210)
 930 {
 931         int retval;
 932         u32 command = fotg210_readl(fotg210, &fotg210->regs->command);
 933
 934         /* If the EHCI debug controller is active, special care must be
 935          * taken before and after a host controller reset
 936          */
 937         if (fotg210->debug && !dbgp_reset_prep(fotg210_to_hcd(fotg210)))
 938                 fotg210->debug = NULL;
 939
 940         command |= CMD_RESET;
 941         dbg_cmd(fotg210, "reset", command);
 942         fotg210_writel(fotg210, command, &fotg210->regs->command);
 943         fotg210->rh_state = FOTG210_RH_HALTED;
 944         fotg210->next_statechange = jiffies;
 945         retval = handshake(fotg210, &fotg210->regs->command,
 946                         CMD_RESET, 0, 250 * 1000);
 947
 948         if (retval)
 949                 return retval;
 950
 951         if (fotg210->debug)
 952                 dbgp_external_startup(fotg210_to_hcd(fotg210));
 953
 954         fotg210->port_c_suspend = fotg210->suspended_ports =
 955                         fotg210->resuming_ports = 0;
 956         return retval;
 957 }
 958
 959 /* Idle the controller (turn off the schedules).
 960  * Must be called with interrupts enabled and the lock not held.
 961  */
 962 static void fotg210_quiesce(struct fotg210_hcd *fotg210)
 963 {
 964         u32 temp;
 965
 966         if (fotg210->rh_state != FOTG210_RH_RUNNING)
 967                 return;
 968
 969         /* wait for any schedule enables/disables to take effect */
 970         temp = (fotg210->command << 10) & (STS_ASS | STS_PSS);
 971         handshake(fotg210, &fotg210->regs->status, STS_ASS | STS_PSS, temp,
 972                         16 * 125);
 973
 974         /* then disable anything that's still active */
 975         spin_lock_irq(&fotg210->lock);
 976         fotg210->command &= ~(CMD_ASE | CMD_PSE);
 977         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
 978         spin_unlock_irq(&fotg210->lock);
 979
 980         /* hardware can take 16 microframes to turn off ... */
 981         handshake(fotg210, &fotg210->regs->status, STS_ASS | STS_PSS, 0,
 982                         16 * 125);
 983 }
 984
 985 static void end_unlink_async(struct fotg210_hcd *fotg210);
 986 static void unlink_empty_async(struct fotg210_hcd *fotg210);
 987 static void fotg210_work(struct fotg210_hcd *fotg210);
 988 static void start_unlink_intr(struct fotg210_hcd *fotg210,
 989                               struct fotg210_qh *qh);
 990 static void end_unlink_intr(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
 991
 992 /* Set a bit in the USBCMD register */
 993 static void fotg210_set_command_bit(struct fotg210_hcd *fotg210, u32 bit)
 994 {
 995         fotg210->command |= bit;
 996         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
 997
 998         /* unblock posted write */
 999         fotg210_readl(fotg210, &fotg210->regs->command);
1000 }
1001
1002 /* Clear a bit in the USBCMD register */
1003 static void fotg210_clear_command_bit(struct fotg210_hcd *fotg210, u32 bit)
1004 {
1005         fotg210->command &= ~bit;
1006         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
1007
1008         /* unblock posted write */
1009         fotg210_readl(fotg210, &fotg210->regs->command);
1010 }
1011
1012 /* EHCI timer support...  Now using hrtimers.
1013  *
1014  * Lots of different events are triggered from fotg210->hrtimer.  Whenever
1015  * the timer routine runs, it checks each possible event; events that are
1016  * currently enabled and whose expiration time has passed get handled.
1017  * The set of enabled events is stored as a collection of bitflags in
1018  * fotg210->enabled_hrtimer_events, and they are numbered in order of
1019  * increasing delay values (ranging between 1 ms and 100 ms).
1020  *
1021  * Rather than implementing a sorted list or tree of all pending events,
1022  * we keep track only of the lowest-numbered pending event, in
1023  * fotg210->next_hrtimer_event.  Whenever fotg210->hrtimer gets restarted, its
1024  * expiration time is set to the timeout value for this event.
1025  *
1026  * As a result, events might not get handled right away; the actual delay
1027  * could be anywhere up to twice the requested delay.  This doesn't
1028  * matter, because none of the events are especially time-critical.  The
1029  * ones that matter most all have a delay of 1 ms, so they will be
1030  * handled after 2 ms at most, which is okay.  In addition to this, we
1031  * allow for an expiration range of 1 ms.
1032  */
1033
1034 /* Delay lengths for the hrtimer event types.
1035  * Keep this list sorted by delay length, in the same order as
1036  * the event types indexed by enum fotg210_hrtimer_event in fotg210.h.
1037  */
1038 static unsigned event_delays_ns[] = {
1039         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_ASS */
1040         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_PSS */
1041         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_DEAD */
1042         1125 * NSEC_PER_USEC,   /* FOTG210_HRTIMER_UNLINK_INTR */
1043         2 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_FREE_ITDS */
1044         6 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_ASYNC_UNLINKS */
1045         10 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_IAA_WATCHDOG */
1046         10 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_DISABLE_PERIODIC */
1047         15 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_DISABLE_ASYNC */
1048         100 * NSEC_PER_MSEC,    /* FOTG210_HRTIMER_IO_WATCHDOG */
1049 };
1050
1051 /* Enable a pending hrtimer event */
1052 static void fotg210_enable_event(struct fotg210_hcd *fotg210, unsigned event,
1053                 bool resched)
1054 {
1055         ktime_t *timeout = &fotg210->hr_timeouts[event];
1056
1057         if (resched)
1058                 *timeout = ktime_add(ktime_get(), event_delays_ns[event]);
1059         fotg210->enabled_hrtimer_events |= (1 << event);
1060
1061         /* Track only the lowest-numbered pending event */
1062         if (event < fotg210->next_hrtimer_event) {
1063                 fotg210->next_hrtimer_event = event;
1064                 hrtimer_start_range_ns(&fotg210->hrtimer, *timeout,
1065                                 NSEC_PER_MSEC, HRTIMER_MODE_ABS);
1066         }
1067 }
1068
1069
1070 /* Poll the STS_ASS status bit; see when it agrees with CMD_ASE */
1071 static void fotg210_poll_ASS(struct fotg210_hcd *fotg210)
1072 {
1073         unsigned actual, want;
1074
1075         /* Don't enable anything if the controller isn't running (e.g., died) */
1076         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1077                 return;
1078
1079         want = (fotg210->command & CMD_ASE) ? STS_ASS : 0;
1080         actual = fotg210_readl(fotg210, &fotg210->regs->status) & STS_ASS;
1081
1082         if (want != actual) {
1083
1084                 /* Poll again later, but give up after about 20 ms */
1085                 if (fotg210->ASS_poll_count++ < 20) {
1086                         fotg210_enable_event(fotg210, FOTG210_HRTIMER_POLL_ASS,
1087                                         true);
1088                         return;
1089                 }
1090                 fotg210_dbg(fotg210, "Waited too long for the async schedule status (%x/%x), giving up\n",
1091                                 want, actual);
1092         }
1093         fotg210->ASS_poll_count = 0;
1094
1095         /* The status is up-to-date; restart or stop the schedule as needed */
1096         if (want == 0) {        /* Stopped */
1097                 if (fotg210->async_count > 0)
1098                         fotg210_set_command_bit(fotg210, CMD_ASE);
1099
1100         } else {                /* Running */
1101                 if (fotg210->async_count == 0) {
1102
1103                         /* Turn off the schedule after a while */
1104                         fotg210_enable_event(fotg210,
1105                                         FOTG210_HRTIMER_DISABLE_ASYNC,
1106                                         true);
1107                 }
1108         }
1109 }
1110
1111 /* Turn off the async schedule after a brief delay */
1112 static void fotg210_disable_ASE(struct fotg210_hcd *fotg210)
1113 {
1114         fotg210_clear_command_bit(fotg210, CMD_ASE);
1115 }
1116
1117
1118 /* Poll the STS_PSS status bit; see when it agrees with CMD_PSE */
1119 static void fotg210_poll_PSS(struct fotg210_hcd *fotg210)
1120 {
1121         unsigned actual, want;
1122
1123         /* Don't do anything if the controller isn't running (e.g., died) */
1124         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1125                 return;
1126
1127         want = (fotg210->command & CMD_PSE) ? STS_PSS : 0;
1128         actual = fotg210_readl(fotg210, &fotg210->regs->status) & STS_PSS;
1129
1130         if (want != actual) {
1131
1132                 /* Poll again later, but give up after about 20 ms */
1133                 if (fotg210->PSS_poll_count++ < 20) {
1134                         fotg210_enable_event(fotg210, FOTG210_HRTIMER_POLL_PSS,
1135                                         true);
1136                         return;
1137                 }
1138                 fotg210_dbg(fotg210, "Waited too long for the periodic schedule status (%x/%x), giving up\n",
1139                                 want, actual);
1140         }
1141         fotg210->PSS_poll_count = 0;
1142
1143         /* The status is up-to-date; restart or stop the schedule as needed */
1144         if (want == 0) {        /* Stopped */
1145                 if (fotg210->periodic_count > 0)
1146                         fotg210_set_command_bit(fotg210, CMD_PSE);
1147
1148         } else {                /* Running */
1149                 if (fotg210->periodic_count == 0) {
1150
1151                         /* Turn off the schedule after a while */
1152                         fotg210_enable_event(fotg210,
1153                                         FOTG210_HRTIMER_DISABLE_PERIODIC,
1154                                         true);
1155                 }
1156         }
1157 }
1158
1159 /* Turn off the periodic schedule after a brief delay */
1160 static void fotg210_disable_PSE(struct fotg210_hcd *fotg210)
1161 {
1162         fotg210_clear_command_bit(fotg210, CMD_PSE);
1163 }
1164
1165
1166 /* Poll the STS_HALT status bit; see when a dead controller stops */
1167 static void fotg210_handle_controller_death(struct fotg210_hcd *fotg210)
1168 {
1169         if (!(fotg210_readl(fotg210, &fotg210->regs->status) & STS_HALT)) {
1170
1171                 /* Give up after a few milliseconds */
1172                 if (fotg210->died_poll_count++ < 5) {
1173                         /* Try again later */
1174                         fotg210_enable_event(fotg210,
1175                                         FOTG210_HRTIMER_POLL_DEAD, true);
1176                         return;
1177                 }
1178                 fotg210_warn(fotg210, "Waited too long for the controller to stop, giving up\n");
1179         }
1180
1181         /* Clean up the mess */
1182         fotg210->rh_state = FOTG210_RH_HALTED;
1183         fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
1184         fotg210_work(fotg210);
1185         end_unlink_async(fotg210);
1186
1187         /* Not in process context, so don't try to reset the controller */
1188 }
1189
1190
1191 /* Handle unlinked interrupt QHs once they are gone from the hardware */
1192 static void fotg210_handle_intr_unlinks(struct fotg210_hcd *fotg210)
1193 {
1194         bool stopped = (fotg210->rh_state < FOTG210_RH_RUNNING);
1195
1196         /*
1197          * Process all the QHs on the intr_unlink list that were added
1198          * before the current unlink cycle began.  The list is in
1199          * temporal order, so stop when we reach the first entry in the
1200          * current cycle.  But if the root hub isn't running then
1201          * process all the QHs on the list.
1202          */
1203         fotg210->intr_unlinking = true;
1204         while (fotg210->intr_unlink) {
1205                 struct fotg210_qh *qh = fotg210->intr_unlink;
1206
1207                 if (!stopped && qh->unlink_cycle == fotg210->intr_unlink_cycle)
1208                         break;
1209                 fotg210->intr_unlink = qh->unlink_next;
1210                 qh->unlink_next = NULL;
1211                 end_unlink_intr(fotg210, qh);
1212         }
1213
1214         /* Handle remaining entries later */
1215         if (fotg210->intr_unlink) {
1216                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_UNLINK_INTR,
1217                                 true);
1218                 ++fotg210->intr_unlink_cycle;
1219         }
1220         fotg210->intr_unlinking = false;
1221 }
1222
1223
1224 /* Start another free-iTDs/siTDs cycle */
1225 static void start_free_itds(struct fotg210_hcd *fotg210)
1226 {
1227         if (!(fotg210->enabled_hrtimer_events &
1228                         BIT(FOTG210_HRTIMER_FREE_ITDS))) {
1229                 fotg210->last_itd_to_free = list_entry(
1230                                 fotg210->cached_itd_list.prev,
1231                                 struct fotg210_itd, itd_list);
1232                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_FREE_ITDS, true);
1233         }
1234 }
1235
1236 /* Wait for controller to stop using old iTDs and siTDs */
1237 static void end_free_itds(struct fotg210_hcd *fotg210)
1238 {
1239         struct fotg210_itd *itd, *n;
1240
1241         if (fotg210->rh_state < FOTG210_RH_RUNNING)
1242                 fotg210->last_itd_to_free = NULL;
1243
1244         list_for_each_entry_safe(itd, n, &fotg210->cached_itd_list, itd_list) {
1245                 list_del(&itd->itd_list);
1246                 dma_pool_free(fotg210->itd_pool, itd, itd->itd_dma);
1247                 if (itd == fotg210->last_itd_to_free)
1248                         break;
1249         }
1250
1251         if (!list_empty(&fotg210->cached_itd_list))
1252                 start_free_itds(fotg210);
1253 }
1254
1255
1256 /* Handle lost (or very late) IAA interrupts */
1257 static void fotg210_iaa_watchdog(struct fotg210_hcd *fotg210)
1258 {
1259         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1260                 return;
1261
1262         /*
1263          * Lost IAA irqs wedge things badly; seen first with a vt8235.
1264          * So we need this watchdog, but must protect it against both
1265          * (a) SMP races against real IAA firing and retriggering, and
1266          * (b) clean HC shutdown, when IAA watchdog was pending.
1267          */
1268         if (fotg210->async_iaa) {
1269                 u32 cmd, status;
1270
1271                 /* If we get here, IAA is *REALLY* late.  It's barely
1272                  * conceivable that the system is so busy that CMD_IAAD
1273                  * is still legitimately set, so let's be sure it's
1274                  * clear before we read STS_IAA.  (The HC should clear
1275                  * CMD_IAAD when it sets STS_IAA.)
1276                  */
1277                 cmd = fotg210_readl(fotg210, &fotg210->regs->command);
1278
1279                 /*
1280                  * If IAA is set here it either legitimately triggered
1281                  * after the watchdog timer expired (_way_ late, so we'll
1282                  * still count it as lost) ... or a silicon erratum:
1283                  * - VIA seems to set IAA without triggering the IRQ;
1284                  * - IAAD potentially cleared without setting IAA.
1285                  */
1286                 status = fotg210_readl(fotg210, &fotg210->regs->status);
1287                 if ((status & STS_IAA) || !(cmd & CMD_IAAD)) {
1288                         COUNT(fotg210->stats.lost_iaa);
1289                         fotg210_writel(fotg210, STS_IAA,
1290                                         &fotg210->regs->status);
1291                 }
1292
1293                 fotg210_dbg(fotg210, "IAA watchdog: status %x cmd %x\n",
1294                                 status, cmd);
1295                 end_unlink_async(fotg210);
1296         }
1297 }
1298
1299
1300 /* Enable the I/O watchdog, if appropriate */
1301 static void turn_on_io_watchdog(struct fotg210_hcd *fotg210)
1302 {
1303         /* Not needed if the controller isn't running or it's already enabled */
1304         if (fotg210->rh_state != FOTG210_RH_RUNNING ||
1305                         (fotg210->enabled_hrtimer_events &
1306                         BIT(FOTG210_HRTIMER_IO_WATCHDOG)))
1307                 return;
1308
1309         /*
1310          * Isochronous transfers always need the watchdog.
1311          * For other sorts we use it only if the flag is set.
1312          */
1313         if (fotg210->isoc_count > 0 || (fotg210->need_io_watchdog &&
1314                         fotg210->async_count + fotg210->intr_count > 0))
1315                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_IO_WATCHDOG,
1316                                 true);
1317 }
1318
1319
1320 /* Handler functions for the hrtimer event types.
1321  * Keep this array in the same order as the event types indexed by
1322  * enum fotg210_hrtimer_event in fotg210.h.
1323  */
1324 static void (*event_handlers[])(struct fotg210_hcd *) = {
1325         fotg210_poll_ASS,                       /* FOTG210_HRTIMER_POLL_ASS */
1326         fotg210_poll_PSS,                       /* FOTG210_HRTIMER_POLL_PSS */
1327         fotg210_handle_controller_death,        /* FOTG210_HRTIMER_POLL_DEAD */
1328         fotg210_handle_intr_unlinks,    /* FOTG210_HRTIMER_UNLINK_INTR */
1329         end_free_itds,                  /* FOTG210_HRTIMER_FREE_ITDS */
1330         unlink_empty_async,             /* FOTG210_HRTIMER_ASYNC_UNLINKS */
1331         fotg210_iaa_watchdog,           /* FOTG210_HRTIMER_IAA_WATCHDOG */
1332         fotg210_disable_PSE,            /* FOTG210_HRTIMER_DISABLE_PERIODIC */
1333         fotg210_disable_ASE,            /* FOTG210_HRTIMER_DISABLE_ASYNC */
1334         fotg210_work,                   /* FOTG210_HRTIMER_IO_WATCHDOG */
1335 };
1336
1337 static enum hrtimer_restart fotg210_hrtimer_func(struct hrtimer *t)
1338 {
1339         struct fotg210_hcd *fotg210 =
1340                         container_of(t, struct fotg210_hcd, hrtimer);
1341         ktime_t now;
1342         unsigned long events;
1343         unsigned long flags;
1344         unsigned e;
1345
1346         spin_lock_irqsave(&fotg210->lock, flags);
1347
1348         events = fotg210->enabled_hrtimer_events;
1349         fotg210->enabled_hrtimer_events = 0;
1350         fotg210->next_hrtimer_event = FOTG210_HRTIMER_NO_EVENT;
1351
1352         /*
1353          * Check each pending event.  If its time has expired, handle
1354          * the event; otherwise re-enable it.
1355          */
1356         now = ktime_get();
1357         for_each_set_bit(e, &events, FOTG210_HRTIMER_NUM_EVENTS) {
1358                 if (ktime_compare(now, fotg210->hr_timeouts[e]) >= 0)
1359                         event_handlers[e](fotg210);
1360                 else
1361                         fotg210_enable_event(fotg210, e, false);
1362         }
1363
1364         spin_unlock_irqrestore(&fotg210->lock, flags);
1365         return HRTIMER_NORESTART;
1366 }
1367
1368 #define fotg210_bus_suspend NULL
1369 #define fotg210_bus_resume NULL
1370
1371 static int check_reset_complete(struct fotg210_hcd *fotg210, int index,
1372                 u32 __iomem *status_reg, int port_status)
1373 {
1374         if (!(port_status & PORT_CONNECT))
1375                 return port_status;
1376
1377         /* if reset finished and it's still not enabled -- handoff */
1378         if (!(port_status & PORT_PE))
1379                 /* with integrated TT, there's nobody to hand it to! */
1380                 fotg210_dbg(fotg210, "Failed to enable port %d on root hub TT\n",
1381                                 index + 1);
1382         else
1383                 fotg210_dbg(fotg210, "port %d reset complete, port enabled\n",
1384                                 index + 1);
1385
1386         return port_status;
1387 }
1388
1389
1390 /* build "status change" packet (one or two bytes) from HC registers */
1391
1392 static int fotg210_hub_status_data(struct usb_hcd *hcd, char *buf)
1393 {
1394         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
1395         u32 temp, status;
1396         u32 mask;
1397         int retval = 1;
1398         unsigned long flags;
1399
1400         /* init status to no-changes */
1401         buf[0] = 0;
1402
1403         /* Inform the core about resumes-in-progress by returning
1404          * a non-zero value even if there are no status changes.
1405          */
1406         status = fotg210->resuming_ports;
1407
1408         mask = PORT_CSC | PORT_PEC;
1409         /* PORT_RESUME from hardware ~= PORT_STAT_C_SUSPEND */
1410
1411         /* no hub change reports (bit 0) for now (power, ...) */
1412
1413         /* port N changes (bit N)? */
1414         spin_lock_irqsave(&fotg210->lock, flags);
1415
1416         temp = fotg210_readl(fotg210, &fotg210->regs->port_status);
1417
1418         /*
1419          * Return status information even for ports with OWNER set.
1420          * Otherwise hub_wq wouldn't see the disconnect event when a
1421          * high-speed device is switched over to the companion
1422          * controller by the user.
1423          */
1424
1425         if ((temp & mask) != 0 || test_bit(0, &fotg210->port_c_suspend) ||
1426                         (fotg210->reset_done[0] &&
1427                         time_after_eq(jiffies, fotg210->reset_done[0]))) {
1428                 buf[0] |= 1 << 1;
1429                 status = STS_PCD;
1430         }
1431         /* FIXME autosuspend idle root hubs */
1432         spin_unlock_irqrestore(&fotg210->lock, flags);
1433         return status ? retval : 0;
1434 }
1435
1436 static void fotg210_hub_descriptor(struct fotg210_hcd *fotg210,
1437                 struct usb_hub_descriptor *desc)
1438 {
1439         int ports = HCS_N_PORTS(fotg210->hcs_params);
1440         u16 temp;
1441
1442         desc->bDescriptorType = USB_DT_HUB;
1443         desc->bPwrOn2PwrGood = 10;      /* fotg210 1.0, 2.3.9 says 20ms max */
1444         desc->bHubContrCurrent = 0;
1445
1446         desc->bNbrPorts = ports;
1447         temp = 1 + (ports / 8);
1448         desc->bDescLength = 7 + 2 * temp;
1449
1450         /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
1451         memset(&desc->u.hs.DeviceRemovable[0], 0, temp);
1452         memset(&desc->u.hs.DeviceRemovable[temp], 0xff, temp);
1453
1454         temp = HUB_CHAR_INDV_PORT_OCPM; /* per-port overcurrent reporting */
1455         temp |= HUB_CHAR_NO_LPSM;       /* no power switching */
1456         desc->wHubCharacteristics = cpu_to_le16(temp);
1457 }
1458
1459 static int fotg210_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
1460                 u16 wIndex, char *buf, u16 wLength)
1461 {
1462         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
1463         int ports = HCS_N_PORTS(fotg210->hcs_params);
1464         u32 __iomem *status_reg = &fotg210->regs->port_status;
1465         u32 temp, temp1, status;
1466         unsigned long flags;
1467         int retval = 0;
1468         unsigned selector;
1469
1470         /*
1471          * FIXME:  support SetPortFeatures USB_PORT_FEAT_INDICATOR.
1472          * HCS_INDICATOR may say we can change LEDs to off/amber/green.
1473          * (track current state ourselves) ... blink for diagnostics,
1474          * power, "this is the one", etc.  EHCI spec supports this.
1475          */
1476
1477         spin_lock_irqsave(&fotg210->lock, flags);
1478         switch (typeReq) {
1479         case ClearHubFeature:
1480                 switch (wValue) {
1481                 case C_HUB_LOCAL_POWER:
1482                 case C_HUB_OVER_CURRENT:
1483                         /* no hub-wide feature/status flags */
1484                         break;
1485                 default:
1486                         goto error;
1487                 }
1488                 break;
1489         case ClearPortFeature:
1490                 if (!wIndex || wIndex > ports)
1491                         goto error;
1492                 wIndex--;
1493                 temp = fotg210_readl(fotg210, status_reg);
1494                 temp &= ~PORT_RWC_BITS;
1495
1496                 /*
1497                  * Even if OWNER is set, so the port is owned by the
1498                  * companion controller, hub_wq needs to be able to clear
1499                  * the port-change status bits (especially
1500                  * USB_PORT_STAT_C_CONNECTION).
1501                  */
1502
1503                 switch (wValue) {
1504                 case USB_PORT_FEAT_ENABLE:
1505                         fotg210_writel(fotg210, temp & ~PORT_PE, status_reg);
1506                         break;
1507                 case USB_PORT_FEAT_C_ENABLE:
1508                         fotg210_writel(fotg210, temp | PORT_PEC, status_reg);
1509                         break;
1510                 case USB_PORT_FEAT_SUSPEND:
1511                         if (temp & PORT_RESET)
1512                                 goto error;
1513                         if (!(temp & PORT_SUSPEND))
1514                                 break;
1515                         if ((temp & PORT_PE) == 0)
1516                                 goto error;
1517
1518                         /* resume signaling for 20 msec */
1519                         fotg210_writel(fotg210, temp | PORT_RESUME, status_reg);
1520                         fotg210->reset_done[wIndex] = jiffies
1521                                         + msecs_to_jiffies(USB_RESUME_TIMEOUT);
1522                         break;
1523                 case USB_PORT_FEAT_C_SUSPEND:
1524                         clear_bit(wIndex, &fotg210->port_c_suspend);
1525                         break;
1526                 case USB_PORT_FEAT_C_CONNECTION:
1527                         fotg210_writel(fotg210, temp | PORT_CSC, status_reg);
1528                         break;
1529                 case USB_PORT_FEAT_C_OVER_CURRENT:
1530                         fotg210_writel(fotg210, temp | OTGISR_OVC,
1531                                         &fotg210->regs->otgisr);
1532                         break;
1533                 case USB_PORT_FEAT_C_RESET:
1534                         /* GetPortStatus clears reset */
1535                         break;
1536                 default:
1537                         goto error;
1538                 }
1539                 fotg210_readl(fotg210, &fotg210->regs->command);
1540                 break;
1541         case GetHubDescriptor:
1542                 fotg210_hub_descriptor(fotg210, (struct usb_hub_descriptor *)
1543                                 buf);
1544                 break;
1545         case GetHubStatus:
1546                 /* no hub-wide feature/status flags */
1547                 memset(buf, 0, 4);
1548                 /*cpu_to_le32s ((u32 *) buf); */
1549                 break;
1550         case GetPortStatus:
1551                 if (!wIndex || wIndex > ports)
1552                         goto error;
1553                 wIndex--;
1554                 status = 0;
1555                 temp = fotg210_readl(fotg210, status_reg);
1556
1557                 /* wPortChange bits */
1558                 if (temp & PORT_CSC)
1559                         status |= USB_PORT_STAT_C_CONNECTION << 16;
1560                 if (temp & PORT_PEC)
1561                         status |= USB_PORT_STAT_C_ENABLE << 16;
1562
1563                 temp1 = fotg210_readl(fotg210, &fotg210->regs->otgisr);
1564                 if (temp1 & OTGISR_OVC)
1565                         status |= USB_PORT_STAT_C_OVERCURRENT << 16;
1566
1567                 /* whoever resumes must GetPortStatus to complete it!! */
1568                 if (temp & PORT_RESUME) {
1569
1570                         /* Remote Wakeup received? */
1571                         if (!fotg210->reset_done[wIndex]) {
1572                                 /* resume signaling for 20 msec */
1573                                 fotg210->reset_done[wIndex] = jiffies
1574                                                 + msecs_to_jiffies(20);
1575                                 /* check the port again */
1576                                 mod_timer(&fotg210_to_hcd(fotg210)->rh_timer,
1577                                                 fotg210->reset_done[wIndex]);
1578                         }
1579
1580                         /* resume completed? */
1581                         else if (time_after_eq(jiffies,
1582                                         fotg210->reset_done[wIndex])) {
1583                                 clear_bit(wIndex, &fotg210->suspended_ports);
1584                                 set_bit(wIndex, &fotg210->port_c_suspend);
1585                                 fotg210->reset_done[wIndex] = 0;
1586
1587                                 /* stop resume signaling */
1588                                 temp = fotg210_readl(fotg210, status_reg);
1589                                 fotg210_writel(fotg210, temp &
1590                                                 ~(PORT_RWC_BITS | PORT_RESUME),
1591                                                 status_reg);
1592                                 clear_bit(wIndex, &fotg210->resuming_ports);
1593                                 retval = handshake(fotg210, status_reg,
1594                                                 PORT_RESUME, 0, 2000);/* 2ms */
1595                                 if (retval != 0) {
1596                                         fotg210_err(fotg210,
1597                                                         "port %d resume error %d\n",
1598                                                         wIndex + 1, retval);
1599                                         goto error;
1600                                 }
1601                                 temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
1602                         }
1603                 }
1604
1605                 /* whoever resets must GetPortStatus to complete it!! */
1606                 if ((temp & PORT_RESET) && time_after_eq(jiffies,
1607                                 fotg210->reset_done[wIndex])) {
1608                         status |= USB_PORT_STAT_C_RESET << 16;
1609                         fotg210->reset_done[wIndex] = 0;
1610                         clear_bit(wIndex, &fotg210->resuming_ports);
1611
1612                         /* force reset to complete */
1613                         fotg210_writel(fotg210,
1614                                         temp & ~(PORT_RWC_BITS | PORT_RESET),
1615                                         status_reg);
1616                         /* REVISIT:  some hardware needs 550+ usec to clear
1617                          * this bit; seems too long to spin routinely...
1618                          */
1619                         retval = handshake(fotg210, status_reg,
1620                                         PORT_RESET, 0, 1000);
1621                         if (retval != 0) {
1622                                 fotg210_err(fotg210, "port %d reset error %d\n",
1623                                                 wIndex + 1, retval);
1624                                 goto error;
1625                         }
1626
1627                         /* see what we found out */
1628                         temp = check_reset_complete(fotg210, wIndex, status_reg,
1629                                         fotg210_readl(fotg210, status_reg));
1630
1631                         /* restart schedule */
1632                         fotg210->command |= CMD_RUN;
1633                         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
1634                 }
1635
1636                 if (!(temp & (PORT_RESUME|PORT_RESET))) {
1637                         fotg210->reset_done[wIndex] = 0;
1638                         clear_bit(wIndex, &fotg210->resuming_ports);
1639                 }
1640
1641                 /* transfer dedicated ports to the companion hc */
1642                 if ((temp & PORT_CONNECT) &&
1643                                 test_bit(wIndex, &fotg210->companion_ports)) {
1644                         temp &= ~PORT_RWC_BITS;
1645                         fotg210_writel(fotg210, temp, status_reg);
1646                         fotg210_dbg(fotg210, "port %d --> companion\n",
1647                                         wIndex + 1);
1648                         temp = fotg210_readl(fotg210, status_reg);
1649                 }
1650
1651                 /*
1652                  * Even if OWNER is set, there's no harm letting hub_wq
1653                  * see the wPortStatus values (they should all be 0 except
1654                  * for PORT_POWER anyway).
1655                  */
1656
1657                 if (temp & PORT_CONNECT) {
1658                         status |= USB_PORT_STAT_CONNECTION;
1659                         status |= fotg210_port_speed(fotg210, temp);
1660                 }
1661                 if (temp & PORT_PE)
1662                         status |= USB_PORT_STAT_ENABLE;
1663
1664                 /* maybe the port was unsuspended without our knowledge */
1665                 if (temp & (PORT_SUSPEND|PORT_RESUME)) {
1666                         status |= USB_PORT_STAT_SUSPEND;
1667                 } else if (test_bit(wIndex, &fotg210->suspended_ports)) {
1668                         clear_bit(wIndex, &fotg210->suspended_ports);
1669                         clear_bit(wIndex, &fotg210->resuming_ports);
1670                         fotg210->reset_done[wIndex] = 0;
1671                         if (temp & PORT_PE)
1672                                 set_bit(wIndex, &fotg210->port_c_suspend);
1673                 }
1674
1675                 temp1 = fotg210_readl(fotg210, &fotg210->regs->otgisr);
1676                 if (temp1 & OTGISR_OVC)
1677                         status |= USB_PORT_STAT_OVERCURRENT;
1678                 if (temp & PORT_RESET)
1679                         status |= USB_PORT_STAT_RESET;
1680                 if (test_bit(wIndex, &fotg210->port_c_suspend))
1681                         status |= USB_PORT_STAT_C_SUSPEND << 16;
1682
1683                 if (status & ~0xffff)   /* only if wPortChange is interesting */
1684                         dbg_port(fotg210, "GetStatus", wIndex + 1, temp);
1685                 put_unaligned_le32(status, buf);
1686                 break;
1687         case SetHubFeature:
1688                 switch (wValue) {
1689                 case C_HUB_LOCAL_POWER:
1690                 case C_HUB_OVER_CURRENT:
1691                         /* no hub-wide feature/status flags */
1692                         break;
1693                 default:
1694                         goto error;
1695                 }
1696                 break;
1697         case SetPortFeature:
1698                 selector = wIndex >> 8;
1699                 wIndex &= 0xff;
1700
1701                 if (!wIndex || wIndex > ports)
1702                         goto error;
1703                 wIndex--;
1704                 temp = fotg210_readl(fotg210, status_reg);
1705                 temp &= ~PORT_RWC_BITS;
1706                 switch (wValue) {
1707                 case USB_PORT_FEAT_SUSPEND:
1708                         if ((temp & PORT_PE) == 0
1709                                         || (temp & PORT_RESET) != 0)
1710                                 goto error;
1711
1712                         /* After above check the port must be connected.
1713                          * Set appropriate bit thus could put phy into low power
1714                          * mode if we have hostpc feature
1715                          */
1716                         fotg210_writel(fotg210, temp | PORT_SUSPEND,
1717                                         status_reg);
1718                         set_bit(wIndex, &fotg210->suspended_ports);
1719                         break;
1720                 case USB_PORT_FEAT_RESET:
1721                         if (temp & PORT_RESUME)
1722                                 goto error;
1723                         /* line status bits may report this as low speed,
1724                          * which can be fine if this root hub has a
1725                          * transaction translator built in.
1726                          */
1727                         fotg210_dbg(fotg210, "port %d reset\n", wIndex + 1);
1728                         temp |= PORT_RESET;
1729                         temp &= ~PORT_PE;
1730
1731                         /*
1732                          * caller must wait, then call GetPortStatus
1733                          * usb 2.0 spec says 50 ms resets on root
1734                          */
1735                         fotg210->reset_done[wIndex] = jiffies
1736                                         + msecs_to_jiffies(50);
1737                         fotg210_writel(fotg210, temp, status_reg);
1738                         break;
1739
1740                 /* For downstream facing ports (these):  one hub port is put
1741                  * into test mode according to USB2 11.24.2.13, then the hub
1742                  * must be reset (which for root hub now means rmmod+modprobe,
1743                  * or else system reboot).  See EHCI 2.3.9 and 4.14 for info
1744                  * about the EHCI-specific stuff.
1745                  */
1746                 case USB_PORT_FEAT_TEST:
1747                         if (!selector || selector > 5)
1748                                 goto error;
1749                         spin_unlock_irqrestore(&fotg210->lock, flags);
1750                         fotg210_quiesce(fotg210);
1751                         spin_lock_irqsave(&fotg210->lock, flags);
1752
1753                         /* Put all enabled ports into suspend */
1754                         temp = fotg210_readl(fotg210, status_reg) &
1755                                 ~PORT_RWC_BITS;
1756                         if (temp & PORT_PE)
1757                                 fotg210_writel(fotg210, temp | PORT_SUSPEND,
1758                                                 status_reg);
1759
1760                         spin_unlock_irqrestore(&fotg210->lock, flags);
1761                         fotg210_halt(fotg210);
1762                         spin_lock_irqsave(&fotg210->lock, flags);
1763
1764                         temp = fotg210_readl(fotg210, status_reg);
1765                         temp |= selector << 16;
1766                         fotg210_writel(fotg210, temp, status_reg);
1767                         break;
1768
1769                 default:
1770                         goto error;
1771                 }
1772                 fotg210_readl(fotg210, &fotg210->regs->command);
1773                 break;
1774
1775         default:
1776 error:
1777                 /* "stall" on error */
1778                 retval = -EPIPE;
1779         }
1780         spin_unlock_irqrestore(&fotg210->lock, flags);
1781         return retval;
1782 }
1783
1784 static void __maybe_unused fotg210_relinquish_port(struct usb_hcd *hcd,
1785                 int portnum)
1786 {
1787         return;
1788 }
1789
1790 static int __maybe_unused fotg210_port_handed_over(struct usb_hcd *hcd,
1791                 int portnum)
1792 {
1793         return 0;
1794 }
1795
1796 /* There's basically three types of memory:
1797  *      - data used only by the HCD ... kmalloc is fine
1798  *      - async and periodic schedules, shared by HC and HCD ... these
1799  *        need to use dma_pool or dma_alloc_coherent
1800  *      - driver buffers, read/written by HC ... single shot DMA mapped
1801  *
1802  * There's also "register" data (e.g. PCI or SOC), which is memory mapped.
1803  * No memory seen by this driver is pageable.
1804  */
1805
1806 /* Allocate the key transfer structures from the previously allocated pool */
1807 static inline void fotg210_qtd_init(struct fotg210_hcd *fotg210,
1808                 struct fotg210_qtd *qtd, dma_addr_t dma)
1809 {
1810         memset(qtd, 0, sizeof(*qtd));
1811         qtd->qtd_dma = dma;
1812         qtd->hw_token = cpu_to_hc32(fotg210, QTD_STS_HALT);
1813         qtd->hw_next = FOTG210_LIST_END(fotg210);
1814         qtd->hw_alt_next = FOTG210_LIST_END(fotg210);
1815         INIT_LIST_HEAD(&qtd->qtd_list);
1816 }
1817
1818 static struct fotg210_qtd *fotg210_qtd_alloc(struct fotg210_hcd *fotg210,
1819                 gfp_t flags)
1820 {
1821         struct fotg210_qtd *qtd;
1822         dma_addr_t dma;
1823
1824         qtd = dma_pool_alloc(fotg210->qtd_pool, flags, &dma);
1825         if (qtd != NULL)
1826                 fotg210_qtd_init(fotg210, qtd, dma);
1827
1828         return qtd;
1829 }
1830
1831 static inline void fotg210_qtd_free(struct fotg210_hcd *fotg210,
1832                 struct fotg210_qtd *qtd)
1833 {
1834         dma_pool_free(fotg210->qtd_pool, qtd, qtd->qtd_dma);
1835 }
1836
1837
1838 static void qh_destroy(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
1839 {
1840         /* clean qtds first, and know this is not linked */
1841         if (!list_empty(&qh->qtd_list) || qh->qh_next.ptr) {
1842                 fotg210_dbg(fotg210, "unused qh not empty!\n");
1843                 BUG();
1844         }
1845         if (qh->dummy)
1846                 fotg210_qtd_free(fotg210, qh->dummy);
1847         dma_pool_free(fotg210->qh_pool, qh->hw, qh->qh_dma);
1848         kfree(qh);
1849 }
1850
1851 static struct fotg210_qh *fotg210_qh_alloc(struct fotg210_hcd *fotg210,
1852                 gfp_t flags)
1853 {
1854         struct fotg210_qh *qh;
1855         dma_addr_t dma;
1856
1857         qh = kzalloc(sizeof(*qh), GFP_ATOMIC);
1858         if (!qh)
1859                 goto done;
1860         qh->hw = dma_pool_zalloc(fotg210->qh_pool, flags, &dma);
1861         if (!qh->hw)
1862                 goto fail;
1863         qh->qh_dma = dma;
1864         INIT_LIST_HEAD(&qh->qtd_list);
1865
1866         /* dummy td enables safe urb queuing */
1867         qh->dummy = fotg210_qtd_alloc(fotg210, flags);
1868         if (qh->dummy == NULL) {
1869                 fotg210_dbg(fotg210, "no dummy td\n");
1870                 goto fail1;
1871         }
1872 done:
1873         return qh;
1874 fail1:
1875         dma_pool_free(fotg210->qh_pool, qh->hw, qh->qh_dma);
1876 fail:
1877         kfree(qh);
1878         return NULL;
1879 }
1880
1881 /* The queue heads and transfer descriptors are managed from pools tied
1882  * to each of the "per device" structures.
1883  * This is the initialisation and cleanup code.
1884  */
1885
1886 static void fotg210_mem_cleanup(struct fotg210_hcd *fotg210)
1887 {
1888         if (fotg210->async)
1889                 qh_destroy(fotg210, fotg210->async);
1890         fotg210->async = NULL;
1891
1892         if (fotg210->dummy)
1893                 qh_destroy(fotg210, fotg210->dummy);
1894         fotg210->dummy = NULL;
1895
1896         /* DMA consistent memory and pools */
1897         dma_pool_destroy(fotg210->qtd_pool);
1898         fotg210->qtd_pool = NULL;
1899
1900         dma_pool_destroy(fotg210->qh_pool);
1901         fotg210->qh_pool = NULL;
1902
1903         dma_pool_destroy(fotg210->itd_pool);
1904         fotg210->itd_pool = NULL;
1905
1906         if (fotg210->periodic)
1907                 dma_free_coherent(fotg210_to_hcd(fotg210)->self.controller,
1908                                 fotg210->periodic_size * sizeof(u32),
1909                                 fotg210->periodic, fotg210->periodic_dma);
1910         fotg210->periodic = NULL;
1911
1912         /* shadow periodic table */
1913         kfree(fotg210->pshadow);
1914         fotg210->pshadow = NULL;
1915 }
1916
1917 /* remember to add cleanup code (above) if you add anything here */
1918 static int fotg210_mem_init(struct fotg210_hcd *fotg210, gfp_t flags)
1919 {
1920         int i;
1921
1922         /* QTDs for control/bulk/intr transfers */
1923         fotg210->qtd_pool = dma_pool_create("fotg210_qtd",
1924                         fotg210_to_hcd(fotg210)->self.controller,
1925                         sizeof(struct fotg210_qtd),
1926                         32 /* byte alignment (for hw parts) */,
1927                         4096 /* can't cross 4K */);
1928         if (!fotg210->qtd_pool)
1929                 goto fail;
1930
1931         /* QHs for control/bulk/intr transfers */
1932         fotg210->qh_pool = dma_pool_create("fotg210_qh",
1933                         fotg210_to_hcd(fotg210)->self.controller,
1934                         sizeof(struct fotg210_qh_hw),
1935                         32 /* byte alignment (for hw parts) */,
1936                         4096 /* can't cross 4K */);
1937         if (!fotg210->qh_pool)
1938                 goto fail;
1939
1940         fotg210->async = fotg210_qh_alloc(fotg210, flags);
1941         if (!fotg210->async)
1942                 goto fail;
1943
1944         /* ITD for high speed ISO transfers */
1945         fotg210->itd_pool = dma_pool_create("fotg210_itd",
1946                         fotg210_to_hcd(fotg210)->self.controller,
1947                         sizeof(struct fotg210_itd),
1948                         64 /* byte alignment (for hw parts) */,
1949                         4096 /* can't cross 4K */);
1950         if (!fotg210->itd_pool)
1951                 goto fail;
1952
1953         /* Hardware periodic table */
1954         fotg210->periodic = (__le32 *)
1955                 dma_alloc_coherent(fotg210_to_hcd(fotg210)->self.controller,
1956                                 fotg210->periodic_size * sizeof(__le32),
1957                                 &fotg210->periodic_dma, 0);
1958         if (fotg210->periodic == NULL)
1959                 goto fail;
1960
1961         for (i = 0; i < fotg210->periodic_size; i++)
1962                 fotg210->periodic[i] = FOTG210_LIST_END(fotg210);
1963
1964         /* software shadow of hardware table */
1965         fotg210->pshadow = kcalloc(fotg210->periodic_size, sizeof(void *),
1966                         flags);
1967         if (fotg210->pshadow != NULL)
1968                 return 0;
1969
1970 fail:
1971         fotg210_dbg(fotg210, "couldn't init memory\n");
1972         fotg210_mem_cleanup(fotg210);
1973         return -ENOMEM;
1974 }
1975 /* EHCI hardware queue manipulation ... the core.  QH/QTD manipulation.
1976  *
1977  * Control, bulk, and interrupt traffic all use "qh" lists.  They list "qtd"
1978  * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned
1979  * buffers needed for the larger number).  We use one QH per endpoint, queue
1980  * multiple urbs (all three types) per endpoint.  URBs may need several qtds.
1981  *
1982  * ISO traffic uses "ISO TD" (itd) records, and (along with
1983  * interrupts) needs careful scheduling.  Performance improvements can be
1984  * an ongoing challenge.  That's in "ehci-sched.c".
1985  *
1986  * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs,
1987  * or otherwise through transaction translators (TTs) in USB 2.0 hubs using
1988  * (b) special fields in qh entries or (c) split iso entries.  TTs will
1989  * buffer low/full speed data so the host collects it at high speed.
1990  */
1991
1992 /* fill a qtd, returning how much of the buffer we were able to queue up */
1993 static int qtd_fill(struct fotg210_hcd *fotg210, struct fotg210_qtd *qtd,
1994                 dma_addr_t buf, size_t len, int token, int maxpacket)
1995 {
1996         int i, count;
1997         u64 addr = buf;
1998
1999         /* one buffer entry per 4K ... first might be short or unaligned */
2000         qtd->hw_buf[0] = cpu_to_hc32(fotg210, (u32)addr);
2001         qtd->hw_buf_hi[0] = cpu_to_hc32(fotg210, (u32)(addr >> 32));
2002         count = 0x1000 - (buf & 0x0fff);        /* rest of that page */
2003         if (likely(len < count))                /* ... iff needed */
2004                 count = len;
2005         else {
2006                 buf +=  0x1000;
2007                 buf &= ~0x0fff;
2008
2009                 /* per-qtd limit: from 16K to 20K (best alignment) */
2010                 for (i = 1; count < len && i < 5; i++) {
2011                         addr = buf;
2012                         qtd->hw_buf[i] = cpu_to_hc32(fotg210, (u32)addr);
2013                         qtd->hw_buf_hi[i] = cpu_to_hc32(fotg210,
2014                                         (u32)(addr >> 32));
2015                         buf += 0x1000;
2016                         if ((count + 0x1000) < len)
2017                                 count += 0x1000;
2018                         else
2019                                 count = len;
2020                 }
2021
2022                 /* short packets may only terminate transfers */
2023                 if (count != len)
2024                         count -= (count % maxpacket);
2025         }
2026         qtd->hw_token = cpu_to_hc32(fotg210, (count << 16) | token);
2027         qtd->length = count;
2028
2029         return count;
2030 }
2031
2032 static inline void qh_update(struct fotg210_hcd *fotg210,
2033                 struct fotg210_qh *qh, struct fotg210_qtd *qtd)
2034 {
2035         struct fotg210_qh_hw *hw = qh->hw;
2036
2037         /* writes to an active overlay are unsafe */
2038         BUG_ON(qh->qh_state != QH_STATE_IDLE);
2039
2040         hw->hw_qtd_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2041         hw->hw_alt_next = FOTG210_LIST_END(fotg210);
2042
2043         /* Except for control endpoints, we make hardware maintain data
2044          * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
2045          * and set the pseudo-toggle in udev. Only usb_clear_halt() will
2046          * ever clear it.
2047          */
2048         if (!(hw->hw_info1 & cpu_to_hc32(fotg210, QH_TOGGLE_CTL))) {
2049                 unsigned is_out, epnum;
2050
2051                 is_out = qh->is_out;
2052                 epnum = (hc32_to_cpup(fotg210, &hw->hw_info1) >> 8) & 0x0f;
2053                 if (unlikely(!usb_gettoggle(qh->dev, epnum, is_out))) {
2054                         hw->hw_token &= ~cpu_to_hc32(fotg210, QTD_TOGGLE);
2055                         usb_settoggle(qh->dev, epnum, is_out, 1);
2056                 }
2057         }
2058
2059         hw->hw_token &= cpu_to_hc32(fotg210, QTD_TOGGLE | QTD_STS_PING);
2060 }
2061
2062 /* if it weren't for a common silicon quirk (writing the dummy into the qh
2063  * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault
2064  * recovery (including urb dequeue) would need software changes to a QH...
2065  */
2066 static void qh_refresh(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
2067 {
2068         struct fotg210_qtd *qtd;
2069
2070         if (list_empty(&qh->qtd_list))
2071                 qtd = qh->dummy;
2072         else {
2073                 qtd = list_entry(qh->qtd_list.next,
2074                                 struct fotg210_qtd, qtd_list);
2075                 /*
2076                  * first qtd may already be partially processed.
2077                  * If we come here during unlink, the QH overlay region
2078                  * might have reference to the just unlinked qtd. The
2079                  * qtd is updated in qh_completions(). Update the QH
2080                  * overlay here.
2081                  */
2082                 if (cpu_to_hc32(fotg210, qtd->qtd_dma) == qh->hw->hw_current) {
2083                         qh->hw->hw_qtd_next = qtd->hw_next;
2084                         qtd = NULL;
2085                 }
2086         }
2087
2088         if (qtd)
2089                 qh_update(fotg210, qh, qtd);
2090 }
2091
2092 static void qh_link_async(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
2093
2094 static void fotg210_clear_tt_buffer_complete(struct usb_hcd *hcd,
2095                 struct usb_host_endpoint *ep)
2096 {
2097         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
2098         struct fotg210_qh *qh = ep->hcpriv;
2099         unsigned long flags;
2100
2101         spin_lock_irqsave(&fotg210->lock, flags);
2102         qh->clearing_tt = 0;
2103         if (qh->qh_state == QH_STATE_IDLE && !list_empty(&qh->qtd_list)
2104                         && fotg210->rh_state == FOTG210_RH_RUNNING)
2105                 qh_link_async(fotg210, qh);
2106         spin_unlock_irqrestore(&fotg210->lock, flags);
2107 }
2108
2109 static void fotg210_clear_tt_buffer(struct fotg210_hcd *fotg210,
2110                 struct fotg210_qh *qh, struct urb *urb, u32 token)
2111 {
2112
2113         /* If an async split transaction gets an error or is unlinked,
2114          * the TT buffer may be left in an indeterminate state.  We
2115          * have to clear the TT buffer.
2116          *
2117          * Note: this routine is never called for Isochronous transfers.
2118          */
2119         if (urb->dev->tt && !usb_pipeint(urb->pipe) && !qh->clearing_tt) {
2120                 struct usb_device *tt = urb->dev->tt->hub;
2121
2122                 dev_dbg(&tt->dev,
2123                                 "clear tt buffer port %d, a%d ep%d t%08x\n",
2124                                 urb->dev->ttport, urb->dev->devnum,
2125                                 usb_pipeendpoint(urb->pipe), token);
2126
2127                 if (urb->dev->tt->hub !=
2128                                 fotg210_to_hcd(fotg210)->self.root_hub) {
2129                         if (usb_hub_clear_tt_buffer(urb) == 0)
2130                                 qh->clearing_tt = 1;
2131                 }
2132         }
2133 }
2134
2135 static int qtd_copy_status(struct fotg210_hcd *fotg210, struct urb *urb,
2136                 size_t length, u32 token)
2137 {
2138         int status = -EINPROGRESS;
2139
2140         /* count IN/OUT bytes, not SETUP (even short packets) */
2141         if (likely(QTD_PID(token) != 2))
2142                 urb->actual_length += length - QTD_LENGTH(token);
2143
2144         /* don't modify error codes */
2145         if (unlikely(urb->unlinked))
2146                 return status;
2147
2148         /* force cleanup after short read; not always an error */
2149         if (unlikely(IS_SHORT_READ(token)))
2150                 status = -EREMOTEIO;
2151
2152         /* serious "can't proceed" faults reported by the hardware */
2153         if (token & QTD_STS_HALT) {
2154                 if (token & QTD_STS_BABBLE) {
2155                         /* FIXME "must" disable babbling device's port too */
2156                         status = -EOVERFLOW;
2157                 /* CERR nonzero + halt --> stall */
2158                 } else if (QTD_CERR(token)) {
2159                         status = -EPIPE;
2160
2161                 /* In theory, more than one of the following bits can be set
2162                  * since they are sticky and the transaction is retried.
2163                  * Which to test first is rather arbitrary.
2164                  */
2165                 } else if (token & QTD_STS_MMF) {
2166                         /* fs/ls interrupt xfer missed the complete-split */
2167                         status = -EPROTO;
2168                 } else if (token & QTD_STS_DBE) {
2169                         status = (QTD_PID(token) == 1) /* IN ? */
2170                                 ? -ENOSR  /* hc couldn't read data */
2171                                 : -ECOMM; /* hc couldn't write data */
2172                 } else if (token & QTD_STS_XACT) {
2173                         /* timeout, bad CRC, wrong PID, etc */
2174                         fotg210_dbg(fotg210, "devpath %s ep%d%s 3strikes\n",
2175                                         urb->dev->devpath,
2176                                         usb_pipeendpoint(urb->pipe),
2177                                         usb_pipein(urb->pipe) ? "in" : "out");
2178                         status = -EPROTO;
2179                 } else {        /* unknown */
2180                         status = -EPROTO;
2181                 }
2182
2183                 fotg210_dbg(fotg210,
2184                                 "dev%d ep%d%s qtd token %08x --> status %d\n",
2185                                 usb_pipedevice(urb->pipe),
2186                                 usb_pipeendpoint(urb->pipe),
2187                                 usb_pipein(urb->pipe) ? "in" : "out",
2188                                 token, status);
2189         }
2190
2191         return status;
2192 }
2193
2194 static void fotg210_urb_done(struct fotg210_hcd *fotg210, struct urb *urb,
2195                 int status)
2196 __releases(fotg210->lock)
2197 __acquires(fotg210->lock)
2198 {
2199         if (likely(urb->hcpriv != NULL)) {
2200                 struct fotg210_qh *qh = (struct fotg210_qh *) urb->hcpriv;
2201
2202                 /* S-mask in a QH means it's an interrupt urb */
2203                 if ((qh->hw->hw_info2 & cpu_to_hc32(fotg210, QH_SMASK)) != 0) {
2204
2205                         /* ... update hc-wide periodic stats (for usbfs) */
2206                         fotg210_to_hcd(fotg210)->self.bandwidth_int_reqs--;
2207                 }
2208         }
2209
2210         if (unlikely(urb->unlinked)) {
2211                 COUNT(fotg210->stats.unlink);
2212         } else {
2213                 /* report non-error and short read status as zero */
2214                 if (status == -EINPROGRESS || status == -EREMOTEIO)
2215                         status = 0;
2216                 COUNT(fotg210->stats.complete);
2217         }
2218
2219 #ifdef FOTG210_URB_TRACE
2220         fotg210_dbg(fotg210,
2221                         "%s %s urb %p ep%d%s status %d len %d/%d\n",
2222                         __func__, urb->dev->devpath, urb,
2223                         usb_pipeendpoint(urb->pipe),
2224                         usb_pipein(urb->pipe) ? "in" : "out",
2225                         status,
2226                         urb->actual_length, urb->transfer_buffer_length);
2227 #endif
2228
2229         /* complete() can reenter this HCD */
2230         usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
2231         spin_unlock(&fotg210->lock);
2232         usb_hcd_giveback_urb(fotg210_to_hcd(fotg210), urb, status);
2233         spin_lock(&fotg210->lock);
2234 }
2235
2236 static int qh_schedule(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
2237
2238 /* Process and free completed qtds for a qh, returning URBs to drivers.
2239  * Chases up to qh->hw_current.  Returns number of completions called,
2240  * indicating how much "real" work we did.
2241  */
2242 static unsigned qh_completions(struct fotg210_hcd *fotg210,
2243                 struct fotg210_qh *qh)
2244 {
2245         struct fotg210_qtd *last, *end = qh->dummy;
2246         struct fotg210_qtd *qtd, *tmp;
2247         int last_status;
2248         int stopped;
2249         unsigned count = 0;
2250         u8 state;
2251         struct fotg210_qh_hw *hw = qh->hw;
2252
2253         if (unlikely(list_empty(&qh->qtd_list)))
2254                 return count;
2255
2256         /* completions (or tasks on other cpus) must never clobber HALT
2257          * till we've gone through and cleaned everything up, even when
2258          * they add urbs to this qh's queue or mark them for unlinking.
2259          *
2260          * NOTE:  unlinking expects to be done in queue order.
2261          *
2262          * It's a bug for qh->qh_state to be anything other than
2263          * QH_STATE_IDLE, unless our caller is scan_async() or
2264          * scan_intr().
2265          */
2266         state = qh->qh_state;
2267         qh->qh_state = QH_STATE_COMPLETING;
2268         stopped = (state == QH_STATE_IDLE);
2269
2270 rescan:
2271         last = NULL;
2272         last_status = -EINPROGRESS;
2273         qh->needs_rescan = 0;
2274
2275         /* remove de-activated QTDs from front of queue.
2276          * after faults (including short reads), cleanup this urb
2277          * then let the queue advance.
2278          * if queue is stopped, handles unlinks.
2279          */
2280         list_for_each_entry_safe(qtd, tmp, &qh->qtd_list, qtd_list) {
2281                 struct urb *urb;
2282                 u32 token = 0;
2283
2284                 urb = qtd->urb;
2285
2286                 /* clean up any state from previous QTD ...*/
2287                 if (last) {
2288                         if (likely(last->urb != urb)) {
2289                                 fotg210_urb_done(fotg210, last->urb,
2290                                                 last_status);
2291                                 count++;
2292                                 last_status = -EINPROGRESS;
2293                         }
2294                         fotg210_qtd_free(fotg210, last);
2295                         last = NULL;
2296                 }
2297
2298                 /* ignore urbs submitted during completions we reported */
2299                 if (qtd == end)
2300                         break;
2301
2302                 /* hardware copies qtd out of qh overlay */
2303                 rmb();
2304                 token = hc32_to_cpu(fotg210, qtd->hw_token);
2305
2306                 /* always clean up qtds the hc de-activated */
2307 retry_xacterr:
2308                 if ((token & QTD_STS_ACTIVE) == 0) {
2309
2310                         /* Report Data Buffer Error: non-fatal but useful */
2311                         if (token & QTD_STS_DBE)
2312                                 fotg210_dbg(fotg210,
2313                                         "detected DataBufferErr for urb %p ep%d%s len %d, qtd %p [qh %p]\n",
2314                                         urb, usb_endpoint_num(&urb->ep->desc),
2315                                         usb_endpoint_dir_in(&urb->ep->desc)
2316                                                 ? "in" : "out",
2317                                         urb->transfer_buffer_length, qtd, qh);
2318
2319                         /* on STALL, error, and short reads this urb must
2320                          * complete and all its qtds must be recycled.
2321                          */
2322                         if ((token & QTD_STS_HALT) != 0) {
2323
2324                                 /* retry transaction errors until we
2325                                  * reach the software xacterr limit
2326                                  */
2327                                 if ((token & QTD_STS_XACT) &&
2328                                                 QTD_CERR(token) == 0 &&
2329                                                 ++qh->xacterrs < QH_XACTERR_MAX &&
2330                                                 !urb->unlinked) {
2331                                         fotg210_dbg(fotg210,
2332                                                 "detected XactErr len %zu/%zu retry %d\n",
2333                                                 qtd->length - QTD_LENGTH(token),
2334                                                 qtd->length,
2335                                                 qh->xacterrs);
2336
2337                                         /* reset the token in the qtd and the
2338                                          * qh overlay (which still contains
2339                                          * the qtd) so that we pick up from
2340                                          * where we left off
2341                                          */
2342                                         token &= ~QTD_STS_HALT;
2343                                         token |= QTD_STS_ACTIVE |
2344                                                  (FOTG210_TUNE_CERR << 10);
2345                                         qtd->hw_token = cpu_to_hc32(fotg210,
2346                                                         token);
2347                                         wmb();
2348                                         hw->hw_token = cpu_to_hc32(fotg210,
2349                                                         token);
2350                                         goto retry_xacterr;
2351                                 }
2352                                 stopped = 1;
2353
2354                         /* magic dummy for some short reads; qh won't advance.
2355                          * that silicon quirk can kick in with this dummy too.
2356                          *
2357                          * other short reads won't stop the queue, including
2358                          * control transfers (status stage handles that) or
2359                          * most other single-qtd reads ... the queue stops if
2360                          * URB_SHORT_NOT_OK was set so the driver submitting
2361                          * the urbs could clean it up.
2362                          */
2363                         } else if (IS_SHORT_READ(token) &&
2364                                         !(qtd->hw_alt_next &
2365                                         FOTG210_LIST_END(fotg210))) {
2366                                 stopped = 1;
2367                         }
2368
2369                 /* stop scanning when we reach qtds the hc is using */
2370                 } else if (likely(!stopped
2371                                 && fotg210->rh_state >= FOTG210_RH_RUNNING)) {
2372                         break;
2373
2374                 /* scan the whole queue for unlinks whenever it stops */
2375                 } else {
2376                         stopped = 1;
2377
2378                         /* cancel everything if we halt, suspend, etc */
2379                         if (fotg210->rh_state < FOTG210_RH_RUNNING)
2380                                 last_status = -ESHUTDOWN;
2381
2382                         /* this qtd is active; skip it unless a previous qtd
2383                          * for its urb faulted, or its urb was canceled.
2384                          */
2385                         else if (last_status == -EINPROGRESS && !urb->unlinked)
2386                                 continue;
2387
2388                         /* qh unlinked; token in overlay may be most current */
2389                         if (state == QH_STATE_IDLE &&
2390                                         cpu_to_hc32(fotg210, qtd->qtd_dma)
2391                                         == hw->hw_current) {
2392                                 token = hc32_to_cpu(fotg210, hw->hw_token);
2393
2394                                 /* An unlink may leave an incomplete
2395                                  * async transaction in the TT buffer.
2396                                  * We have to clear it.
2397                                  */
2398                                 fotg210_clear_tt_buffer(fotg210, qh, urb,
2399                                                 token);
2400                         }
2401                 }
2402
2403                 /* unless we already know the urb's status, collect qtd status
2404                  * and update count of bytes transferred.  in common short read
2405                  * cases with only one data qtd (including control transfers),
2406                  * queue processing won't halt.  but with two or more qtds (for
2407                  * example, with a 32 KB transfer), when the first qtd gets a
2408                  * short read the second must be removed by hand.
2409                  */
2410                 if (last_status == -EINPROGRESS) {
2411                         last_status = qtd_copy_status(fotg210, urb,
2412                                         qtd->length, token);
2413                         if (last_status == -EREMOTEIO &&
2414                                         (qtd->hw_alt_next &
2415                                         FOTG210_LIST_END(fotg210)))
2416                                 last_status = -EINPROGRESS;
2417
2418                         /* As part of low/full-speed endpoint-halt processing
2419                          * we must clear the TT buffer (11.17.5).
2420                          */
2421                         if (unlikely(last_status != -EINPROGRESS &&
2422                                         last_status != -EREMOTEIO)) {
2423                                 /* The TT's in some hubs malfunction when they
2424                                  * receive this request following a STALL (they
2425                                  * stop sending isochronous packets).  Since a
2426                                  * STALL can't leave the TT buffer in a busy
2427                                  * state (if you believe Figures 11-48 - 11-51
2428                                  * in the USB 2.0 spec), we won't clear the TT
2429                                  * buffer in this case.  Strictly speaking this
2430                                  * is a violation of the spec.
2431                                  */
2432                                 if (last_status != -EPIPE)
2433                                         fotg210_clear_tt_buffer(fotg210, qh,
2434                                                         urb, token);
2435                         }
2436                 }
2437
2438                 /* if we're removing something not at the queue head,
2439                  * patch the hardware queue pointer.
2440                  */
2441                 if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
2442                         last = list_entry(qtd->qtd_list.prev,
2443                                         struct fotg210_qtd, qtd_list);
2444                         last->hw_next = qtd->hw_next;
2445                 }
2446
2447                 /* remove qtd; it's recycled after possible urb completion */
2448                 list_del(&qtd->qtd_list);
2449                 last = qtd;
2450
2451                 /* reinit the xacterr counter for the next qtd */
2452                 qh->xacterrs = 0;
2453         }
2454
2455         /* last urb's completion might still need calling */
2456         if (likely(last != NULL)) {
2457                 fotg210_urb_done(fotg210, last->urb, last_status);
2458                 count++;
2459                 fotg210_qtd_free(fotg210, last);
2460         }
2461
2462         /* Do we need to rescan for URBs dequeued during a giveback? */
2463         if (unlikely(qh->needs_rescan)) {
2464                 /* If the QH is already unlinked, do the rescan now. */
2465                 if (state == QH_STATE_IDLE)
2466                         goto rescan;
2467
2468                 /* Otherwise we have to wait until the QH is fully unlinked.
2469                  * Our caller will start an unlink if qh->needs_rescan is
2470                  * set.  But if an unlink has already started, nothing needs
2471                  * to be done.
2472                  */
2473                 if (state != QH_STATE_LINKED)
2474                         qh->needs_rescan = 0;
2475         }
2476
2477         /* restore original state; caller must unlink or relink */
2478         qh->qh_state = state;
2479
2480         /* be sure the hardware's done with the qh before refreshing
2481          * it after fault cleanup, or recovering from silicon wrongly
2482          * overlaying the dummy qtd (which reduces DMA chatter).
2483          */
2484         if (stopped != 0 || hw->hw_qtd_next == FOTG210_LIST_END(fotg210)) {
2485                 switch (state) {
2486                 case QH_STATE_IDLE:
2487                         qh_refresh(fotg210, qh);
2488                         break;
2489                 case QH_STATE_LINKED:
2490                         /* We won't refresh a QH that's linked (after the HC
2491                          * stopped the queue).  That avoids a race:
2492                          *  - HC reads first part of QH;
2493                          *  - CPU updates that first part and the token;
2494                          *  - HC reads rest of that QH, including token
2495                          * Result:  HC gets an inconsistent image, and then
2496                          * DMAs to/from the wrong memory (corrupting it).
2497                          *
2498                          * That should be rare for interrupt transfers,
2499                          * except maybe high bandwidth ...
2500                          */
2501
2502                         /* Tell the caller to start an unlink */
2503                         qh->needs_rescan = 1;
2504                         break;
2505                 /* otherwise, unlink already started */
2506                 }
2507         }
2508
2509         return count;
2510 }
2511
2512 /* reverse of qh_urb_transaction:  free a list of TDs.
2513  * used for cleanup after errors, before HC sees an URB's TDs.
2514  */
2515 static void qtd_list_free(struct fotg210_hcd *fotg210, struct urb *urb,
2516                 struct list_head *head)
2517 {
2518         struct fotg210_qtd *qtd, *temp;
2519
2520         list_for_each_entry_safe(qtd, temp, head, qtd_list) {
2521                 list_del(&qtd->qtd_list);
2522                 fotg210_qtd_free(fotg210, qtd);
2523         }
2524 }
2525
2526 /* create a list of filled qtds for this URB; won't link into qh.
2527  */
2528 static struct list_head *qh_urb_transaction(struct fotg210_hcd *fotg210,
2529                 struct urb *urb, struct list_head *head, gfp_t flags)
2530 {
2531         struct fotg210_qtd *qtd, *qtd_prev;
2532         dma_addr_t buf;
2533         int len, this_sg_len, maxpacket;
2534         int is_input;
2535         u32 token;
2536         int i;
2537         struct scatterlist *sg;
2538
2539         /*
2540          * URBs map to sequences of QTDs:  one logical transaction
2541          */
2542         qtd = fotg210_qtd_alloc(fotg210, flags);
2543         if (unlikely(!qtd))
2544                 return NULL;
2545         list_add_tail(&qtd->qtd_list, head);
2546         qtd->urb = urb;
2547
2548         token = QTD_STS_ACTIVE;
2549         token |= (FOTG210_TUNE_CERR << 10);
2550         /* for split transactions, SplitXState initialized to zero */
2551
2552         len = urb->transfer_buffer_length;
2553         is_input = usb_pipein(urb->pipe);
2554         if (usb_pipecontrol(urb->pipe)) {
2555                 /* SETUP pid */
2556                 qtd_fill(fotg210, qtd, urb->setup_dma,
2557                                 sizeof(struct usb_ctrlrequest),
2558                                 token | (2 /* "setup" */ << 8), 8);
2559
2560                 /* ... and always at least one more pid */
2561                 token ^= QTD_TOGGLE;
2562                 qtd_prev = qtd;
2563                 qtd = fotg210_qtd_alloc(fotg210, flags);
2564                 if (unlikely(!qtd))
2565                         goto cleanup;
2566                 qtd->urb = urb;
2567                 qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2568                 list_add_tail(&qtd->qtd_list, head);
2569
2570                 /* for zero length DATA stages, STATUS is always IN */
2571                 if (len == 0)
2572                         token |= (1 /* "in" */ << 8);
2573         }
2574
2575         /*
2576          * data transfer stage:  buffer setup
2577          */
2578         i = urb->num_mapped_sgs;
2579         if (len > 0 && i > 0) {
2580                 sg = urb->sg;
2581                 buf = sg_dma_address(sg);
2582
2583                 /* urb->transfer_buffer_length may be smaller than the
2584                  * size of the scatterlist (or vice versa)
2585                  */
2586                 this_sg_len = min_t(int, sg_dma_len(sg), len);
2587         } else {
2588                 sg = NULL;
2589                 buf = urb->transfer_dma;
2590                 this_sg_len = len;
2591         }
2592
2593         if (is_input)
2594                 token |= (1 /* "in" */ << 8);
2595         /* else it's already initted to "out" pid (0 << 8) */
2596
2597         maxpacket = usb_maxpacket(urb->dev, urb->pipe, !is_input);
2598
2599         /*
2600          * buffer gets wrapped in one or more qtds;
2601          * last one may be "short" (including zero len)
2602          * and may serve as a control status ack
2603          */
2604         for (;;) {
2605                 int this_qtd_len;
2606
2607                 this_qtd_len = qtd_fill(fotg210, qtd, buf, this_sg_len, token,
2608                                 maxpacket);
2609                 this_sg_len -= this_qtd_len;
2610                 len -= this_qtd_len;
2611                 buf += this_qtd_len;
2612
2613                 /*
2614                  * short reads advance to a "magic" dummy instead of the next
2615                  * qtd ... that forces the queue to stop, for manual cleanup.
2616                  * (this will usually be overridden later.)
2617                  */
2618                 if (is_input)
2619                         qtd->hw_alt_next = fotg210->async->hw->hw_alt_next;
2620
2621                 /* qh makes control packets use qtd toggle; maybe switch it */
2622                 if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
2623                         token ^= QTD_TOGGLE;
2624
2625                 if (likely(this_sg_len <= 0)) {
2626                         if (--i <= 0 || len <= 0)
2627                                 break;
2628                         sg = sg_next(sg);
2629                         buf = sg_dma_address(sg);
2630                         this_sg_len = min_t(int, sg_dma_len(sg), len);
2631                 }
2632
2633                 qtd_prev = qtd;
2634                 qtd = fotg210_qtd_alloc(fotg210, flags);
2635                 if (unlikely(!qtd))
2636                         goto cleanup;
2637                 qtd->urb = urb;
2638                 qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2639                 list_add_tail(&qtd->qtd_list, head);
2640         }
2641
2642         /*
2643          * unless the caller requires manual cleanup after short reads,
2644          * have the alt_next mechanism keep the queue running after the
2645          * last data qtd (the only one, for control and most other cases).
2646          */
2647         if (likely((urb->transfer_flags & URB_SHORT_NOT_OK) == 0 ||
2648                         usb_pipecontrol(urb->pipe)))
2649                 qtd->hw_alt_next = FOTG210_LIST_END(fotg210);
2650
2651         /*
2652          * control requests may need a terminating data "status" ack;
2653          * other OUT ones may need a terminating short packet
2654          * (zero length).
2655          */
2656         if (likely(urb->transfer_buffer_length != 0)) {
2657                 int one_more = 0;
2658
2659                 if (usb_pipecontrol(urb->pipe)) {
2660                         one_more = 1;
2661                         token ^= 0x0100;        /* "in" <--> "out"  */
2662                         token |= QTD_TOGGLE;    /* force DATA1 */
2663                 } else if (usb_pipeout(urb->pipe)
2664                                 && (urb->transfer_flags & URB_ZERO_PACKET)
2665                                 && !(urb->transfer_buffer_length % maxpacket)) {
2666                         one_more = 1;
2667                 }
2668                 if (one_more) {
2669                         qtd_prev = qtd;
2670                         qtd = fotg210_qtd_alloc(fotg210, flags);
2671                         if (unlikely(!qtd))
2672                                 goto cleanup;
2673                         qtd->urb = urb;
2674                         qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2675                         list_add_tail(&qtd->qtd_list, head);
2676
2677                         /* never any data in such packets */
2678                         qtd_fill(fotg210, qtd, 0, 0, token, 0);
2679                 }
2680         }
2681
2682         /* by default, enable interrupt on urb completion */
2683         if (likely(!(urb->transfer_flags & URB_NO_INTERRUPT)))
2684                 qtd->hw_token |= cpu_to_hc32(fotg210, QTD_IOC);
2685         return head;
2686
2687 cleanup:
2688         qtd_list_free(fotg210, urb, head);
2689         return NULL;
2690 }
2691
2692 /* Would be best to create all qh's from config descriptors,
2693  * when each interface/altsetting is established.  Unlink
2694  * any previous qh and cancel its urbs first; endpoints are
2695  * implicitly reset then (data toggle too).
2696  * That'd mean updating how usbcore talks to HCDs. (2.7?)
2697 */
2698
2699
2700 /* Each QH holds a qtd list; a QH is used for everything except iso.
2701  *
2702  * For interrupt urbs, the scheduler must set the microframe scheduling
2703  * mask(s) each time the QH gets scheduled.  For highspeed, that's
2704  * just one microframe in the s-mask.  For split interrupt transactions
2705  * there are additional complications: c-mask, maybe FSTNs.
2706  */
2707 static struct fotg210_qh *qh_make(struct fotg210_hcd *fotg210, struct urb *urb,
2708                 gfp_t flags)
2709 {
2710         struct fotg210_qh *qh = fotg210_qh_alloc(fotg210, flags);
2711         struct usb_host_endpoint *ep;
2712         u32 info1 = 0, info2 = 0;
2713         int is_input, type;
2714         int maxp = 0;
2715         int mult;
2716         struct usb_tt *tt = urb->dev->tt;
2717         struct fotg210_qh_hw *hw;
2718
2719         if (!qh)
2720                 return qh;
2721
2722         /*
2723          * init endpoint/device data for this QH
2724          */
2725         info1 |= usb_pipeendpoint(urb->pipe) << 8;
2726         info1 |= usb_pipedevice(urb->pipe) << 0;
2727
2728         is_input = usb_pipein(urb->pipe);
2729         type = usb_pipetype(urb->pipe);
2730         ep = usb_pipe_endpoint(urb->dev, urb->pipe);
2731         maxp = usb_endpoint_maxp(&ep->desc);
2732         mult = usb_endpoint_maxp_mult(&ep->desc);
2733
2734         /* 1024 byte maxpacket is a hardware ceiling.  High bandwidth
2735          * acts like up to 3KB, but is built from smaller packets.
2736          */
2737         if (maxp > 1024) {
2738                 fotg210_dbg(fotg210, "bogus qh maxpacket %d\n", maxp);
2739                 goto done;
2740         }
2741
2742         /* Compute interrupt scheduling parameters just once, and save.
2743          * - allowing for high bandwidth, how many nsec/uframe are used?
2744          * - split transactions need a second CSPLIT uframe; same question
2745          * - splits also need a schedule gap (for full/low speed I/O)
2746          * - qh has a polling interval
2747          *
2748          * For control/bulk requests, the HC or TT handles these.
2749          */
2750         if (type == PIPE_INTERRUPT) {
2751                 qh->usecs = NS_TO_US(usb_calc_bus_time(USB_SPEED_HIGH,
2752                                 is_input, 0, mult * maxp));
2753                 qh->start = NO_FRAME;
2754
2755                 if (urb->dev->speed == USB_SPEED_HIGH) {
2756                         qh->c_usecs = 0;
2757                         qh->gap_uf = 0;
2758
2759                         qh->period = urb->interval >> 3;
2760                         if (qh->period == 0 && urb->interval != 1) {
2761                                 /* NOTE interval 2 or 4 uframes could work.
2762                                  * But interval 1 scheduling is simpler, and
2763                                  * includes high bandwidth.
2764                                  */
2765                                 urb->interval = 1;
2766                         } else if (qh->period > fotg210->periodic_size) {
2767                                 qh->period = fotg210->periodic_size;
2768                                 urb->interval = qh->period << 3;
2769                         }
2770                 } else {
2771                         int think_time;
2772
2773                         /* gap is f(FS/LS transfer times) */
2774                         qh->gap_uf = 1 + usb_calc_bus_time(urb->dev->speed,
2775                                         is_input, 0, maxp) / (125 * 1000);
2776
2777                         /* FIXME this just approximates SPLIT/CSPLIT times */
2778                         if (is_input) {         /* SPLIT, gap, CSPLIT+DATA */
2779                                 qh->c_usecs = qh->usecs + HS_USECS(0);
2780                                 qh->usecs = HS_USECS(1);
2781                         } else {                /* SPLIT+DATA, gap, CSPLIT */
2782                                 qh->usecs += HS_USECS(1);
2783                                 qh->c_usecs = HS_USECS(0);
2784                         }
2785
2786                         think_time = tt ? tt->think_time : 0;
2787                         qh->tt_usecs = NS_TO_US(think_time +
2788                                         usb_calc_bus_time(urb->dev->speed,
2789                                         is_input, 0, maxp));
2790                         qh->period = urb->interval;
2791                         if (qh->period > fotg210->periodic_size) {
2792                                 qh->period = fotg210->periodic_size;
2793                                 urb->interval = qh->period;
2794                         }
2795                 }
2796         }
2797
2798         /* support for tt scheduling, and access to toggles */
2799         qh->dev = urb->dev;
2800
2801         /* using TT? */
2802         switch (urb->dev->speed) {
2803         case USB_SPEED_LOW:
2804                 info1 |= QH_LOW_SPEED;
2805                 /* FALL THROUGH */
2806
2807         case USB_SPEED_FULL:
2808                 /* EPS 0 means "full" */
2809                 if (type != PIPE_INTERRUPT)
2810                         info1 |= (FOTG210_TUNE_RL_TT << 28);
2811                 if (type == PIPE_CONTROL) {
2812                         info1 |= QH_CONTROL_EP;         /* for TT */
2813                         info1 |= QH_TOGGLE_CTL;         /* toggle from qtd */
2814                 }
2815                 info1 |= maxp << 16;
2816
2817                 info2 |= (FOTG210_TUNE_MULT_TT << 30);
2818
2819                 /* Some Freescale processors have an erratum in which the
2820                  * port number in the queue head was 0..N-1 instead of 1..N.
2821                  */
2822                 if (fotg210_has_fsl_portno_bug(fotg210))
2823                         info2 |= (urb->dev->ttport-1) << 23;
2824                 else
2825                         info2 |= urb->dev->ttport << 23;
2826
2827                 /* set the address of the TT; for TDI's integrated
2828                  * root hub tt, leave it zeroed.
2829                  */
2830                 if (tt && tt->hub != fotg210_to_hcd(fotg210)->self.root_hub)
2831                         info2 |= tt->hub->devnum << 16;
2832
2833                 /* NOTE:  if (PIPE_INTERRUPT) { scheduler sets c-mask } */
2834
2835                 break;
2836
2837         case USB_SPEED_HIGH:            /* no TT involved */
2838                 info1 |= QH_HIGH_SPEED;
2839                 if (type == PIPE_CONTROL) {
2840                         info1 |= (FOTG210_TUNE_RL_HS << 28);
2841                         info1 |= 64 << 16;      /* usb2 fixed maxpacket */
2842                         info1 |= QH_TOGGLE_CTL; /* toggle from qtd */
2843                         info2 |= (FOTG210_TUNE_MULT_HS << 30);
2844                 } else if (type == PIPE_BULK) {
2845                         info1 |= (FOTG210_TUNE_RL_HS << 28);
2846                         /* The USB spec says that high speed bulk endpoints
2847                          * always use 512 byte maxpacket.  But some device
2848                          * vendors decided to ignore that, and MSFT is happy
2849                          * to help them do so.  So now people expect to use
2850                          * such nonconformant devices with Linux too; sigh.
2851                          */
2852                         info1 |= maxp << 16;
2853                         info2 |= (FOTG210_TUNE_MULT_HS << 30);
2854                 } else {                /* PIPE_INTERRUPT */
2855                         info1 |= maxp << 16;
2856                         info2 |= mult << 30;
2857                 }
2858                 break;
2859         default:
2860                 fotg210_dbg(fotg210, "bogus dev %p speed %d\n", urb->dev,
2861                                 urb->dev->speed);
2862 done:
2863                 qh_destroy(fotg210, qh);
2864                 return NULL;
2865         }
2866
2867         /* NOTE:  if (PIPE_INTERRUPT) { scheduler sets s-mask } */
2868
2869         /* init as live, toggle clear, advance to dummy */
2870         qh->qh_state = QH_STATE_IDLE;
2871         hw = qh->hw;
2872         hw->hw_info1 = cpu_to_hc32(fotg210, info1);
2873         hw->hw_info2 = cpu_to_hc32(fotg210, info2);
2874         qh->is_out = !is_input;
2875         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), !is_input, 1);
2876         qh_refresh(fotg210, qh);
2877         return qh;
2878 }
2879
2880 static void enable_async(struct fotg210_hcd *fotg210)
2881 {
2882         if (fotg210->async_count++)
2883                 return;
2884
2885         /* Stop waiting to turn off the async schedule */
2886         fotg210->enabled_hrtimer_events &= ~BIT(FOTG210_HRTIMER_DISABLE_ASYNC);
2887
2888         /* Don't start the schedule until ASS is 0 */
2889         fotg210_poll_ASS(fotg210);
2890         turn_on_io_watchdog(fotg210);
2891 }
2892
2893 static void disable_async(struct fotg210_hcd *fotg210)
2894 {
2895         if (--fotg210->async_count)
2896                 return;
2897
2898         /* The async schedule and async_unlink list are supposed to be empty */
2899         WARN_ON(fotg210->async->qh_next.qh || fotg210->async_unlink);
2900
2901         /* Don't turn off the schedule until ASS is 1 */
2902         fotg210_poll_ASS(fotg210);
2903 }
2904
2905 /* move qh (and its qtds) onto async queue; maybe enable queue.  */
2906
2907 static void qh_link_async(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
2908 {
2909         __hc32 dma = QH_NEXT(fotg210, qh->qh_dma);
2910         struct fotg210_qh *head;
2911
2912         /* Don't link a QH if there's a Clear-TT-Buffer pending */
2913         if (unlikely(qh->clearing_tt))
2914                 return;
2915
2916         WARN_ON(qh->qh_state != QH_STATE_IDLE);
2917
2918         /* clear halt and/or toggle; and maybe recover from silicon quirk */
2919         qh_refresh(fotg210, qh);
2920
2921         /* splice right after start */
2922         head = fotg210->async;
2923         qh->qh_next = head->qh_next;
2924         qh->hw->hw_next = head->hw->hw_next;
2925         wmb();
2926
2927         head->qh_next.qh = qh;
2928         head->hw->hw_next = dma;
2929
2930         qh->xacterrs = 0;
2931         qh->qh_state = QH_STATE_LINKED;
2932         /* qtd completions reported later by interrupt */
2933
2934         enable_async(fotg210);
2935 }
2936
2937 /* For control/bulk/interrupt, return QH with these TDs appended.
2938  * Allocates and initializes the QH if necessary.
2939  * Returns null if it can't allocate a QH it needs to.
2940  * If the QH has TDs (urbs) already, that's great.
2941  */
2942 static struct fotg210_qh *qh_append_tds(struct fotg210_hcd *fotg210,
2943                 struct urb *urb, struct list_head *qtd_list,
2944                 int epnum, void **ptr)
2945 {
2946         struct fotg210_qh *qh = NULL;
2947         __hc32 qh_addr_mask = cpu_to_hc32(fotg210, 0x7f);
2948
2949         qh = (struct fotg210_qh *) *ptr;
2950         if (unlikely(qh == NULL)) {
2951                 /* can't sleep here, we have fotg210->lock... */
2952                 qh = qh_make(fotg210, urb, GFP_ATOMIC);
2953                 *ptr = qh;
2954         }
2955         if (likely(qh != NULL)) {
2956                 struct fotg210_qtd *qtd;
2957
2958                 if (unlikely(list_empty(qtd_list)))
2959                         qtd = NULL;
2960                 else
2961                         qtd = list_entry(qtd_list->next, struct fotg210_qtd,
2962                                         qtd_list);
2963
2964                 /* control qh may need patching ... */
2965                 if (unlikely(epnum == 0)) {
2966                         /* usb_reset_device() briefly reverts to address 0 */
2967                         if (usb_pipedevice(urb->pipe) == 0)
2968                                 qh->hw->hw_info1 &= ~qh_addr_mask;
2969                 }
2970
2971                 /* just one way to queue requests: swap with the dummy qtd.
2972                  * only hc or qh_refresh() ever modify the overlay.
2973                  */
2974                 if (likely(qtd != NULL)) {
2975                         struct fotg210_qtd *dummy;
2976                         dma_addr_t dma;
2977                         __hc32 token;
2978
2979                         /* to avoid racing the HC, use the dummy td instead of
2980                          * the first td of our list (becomes new dummy).  both
2981                          * tds stay deactivated until we're done, when the
2982                          * HC is allowed to fetch the old dummy (4.10.2).
2983                          */
2984                         token = qtd->hw_token;
2985                         qtd->hw_token = HALT_BIT(fotg210);
2986
2987                         dummy = qh->dummy;
2988
2989                         dma = dummy->qtd_dma;
2990                         *dummy = *qtd;
2991                         dummy->qtd_dma = dma;
2992
2993                         list_del(&qtd->qtd_list);
2994                         list_add(&dummy->qtd_list, qtd_list);
2995                         list_splice_tail(qtd_list, &qh->qtd_list);
2996
2997                         fotg210_qtd_init(fotg210, qtd, qtd->qtd_dma);
2998                         qh->dummy = qtd;
2999
3000                         /* hc must see the new dummy at list end */
3001                         dma = qtd->qtd_dma;
3002                         qtd = list_entry(qh->qtd_list.prev,
3003                                         struct fotg210_qtd, qtd_list);
3004                         qtd->hw_next = QTD_NEXT(fotg210, dma);
3005
3006                         /* let the hc process these next qtds */
3007                         wmb();
3008                         dummy->hw_token = token;
3009
3010                         urb->hcpriv = qh;
3011                 }
3012         }
3013         return qh;
3014 }
3015
3016 static int submit_async(struct fotg210_hcd *fotg210, struct urb *urb,
3017                 struct list_head *qtd_list, gfp_t mem_flags)
3018 {
3019         int epnum;
3020         unsigned long flags;
3021         struct fotg210_qh *qh = NULL;
3022         int rc;
3023
3024         epnum = urb->ep->desc.bEndpointAddress;
3025
3026 #ifdef FOTG210_URB_TRACE
3027         {
3028                 struct fotg210_qtd *qtd;
3029
3030                 qtd = list_entry(qtd_list->next, struct fotg210_qtd, qtd_list);
3031                 fotg210_dbg(fotg210,
3032                                 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
3033                                 __func__, urb->dev->devpath, urb,
3034                                 epnum & 0x0f, (epnum & USB_DIR_IN)
3035                                         ? "in" : "out",
3036                                 urb->transfer_buffer_length,
3037                                 qtd, urb->ep->hcpriv);
3038         }
3039 #endif
3040
3041         spin_lock_irqsave(&fotg210->lock, flags);
3042         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
3043                 rc = -ESHUTDOWN;
3044                 goto done;
3045         }
3046         rc = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
3047         if (unlikely(rc))
3048                 goto done;
3049
3050         qh = qh_append_tds(fotg210, urb, qtd_list, epnum, &urb->ep->hcpriv);
3051         if (unlikely(qh == NULL)) {
3052                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
3053                 rc = -ENOMEM;
3054                 goto done;
3055         }
3056
3057         /* Control/bulk operations through TTs don't need scheduling,
3058          * the HC and TT handle it when the TT has a buffer ready.
3059          */
3060         if (likely(qh->qh_state == QH_STATE_IDLE))
3061                 qh_link_async(fotg210, qh);
3062 done:
3063         spin_unlock_irqrestore(&fotg210->lock, flags);
3064         if (unlikely(qh == NULL))
3065                 qtd_list_free(fotg210, urb, qtd_list);
3066         return rc;
3067 }
3068
3069 static void single_unlink_async(struct fotg210_hcd *fotg210,
3070                 struct fotg210_qh *qh)
3071 {
3072         struct fotg210_qh *prev;
3073
3074         /* Add to the end of the list of QHs waiting for the next IAAD */
3075         qh->qh_state = QH_STATE_UNLINK;
3076         if (fotg210->async_unlink)
3077                 fotg210->async_unlink_last->unlink_next = qh;
3078         else
3079                 fotg210->async_unlink = qh;
3080         fotg210->async_unlink_last = qh;
3081
3082         /* Unlink it from the schedule */
3083         prev = fotg210->async;
3084         while (prev->qh_next.qh != qh)
3085                 prev = prev->qh_next.qh;
3086
3087         prev->hw->hw_next = qh->hw->hw_next;
3088         prev->qh_next = qh->qh_next;
3089         if (fotg210->qh_scan_next == qh)
3090                 fotg210->qh_scan_next = qh->qh_next.qh;
3091 }
3092
3093 static void start_iaa_cycle(struct fotg210_hcd *fotg210, bool nested)
3094 {
3095         /*
3096          * Do nothing if an IAA cycle is already running or
3097          * if one will be started shortly.
3098          */
3099         if (fotg210->async_iaa || fotg210->async_unlinking)
3100                 return;
3101
3102         /* Do all the waiting QHs at once */
3103         fotg210->async_iaa = fotg210->async_unlink;
3104         fotg210->async_unlink = NULL;
3105
3106         /* If the controller isn't running, we don't have to wait for it */
3107         if (unlikely(fotg210->rh_state < FOTG210_RH_RUNNING)) {
3108                 if (!nested)            /* Avoid recursion */
3109                         end_unlink_async(fotg210);
3110
3111         /* Otherwise start a new IAA cycle */
3112         } else if (likely(fotg210->rh_state == FOTG210_RH_RUNNING)) {
3113                 /* Make sure the unlinks are all visible to the hardware */
3114                 wmb();
3115
3116                 fotg210_writel(fotg210, fotg210->command | CMD_IAAD,
3117                                 &fotg210->regs->command);
3118                 fotg210_readl(fotg210, &fotg210->regs->command);
3119                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_IAA_WATCHDOG,
3120                                 true);
3121         }
3122 }
3123
3124 /* the async qh for the qtds being unlinked are now gone from the HC */
3125
3126 static void end_unlink_async(struct fotg210_hcd *fotg210)
3127 {
3128         struct fotg210_qh *qh;
3129
3130         /* Process the idle QHs */
3131 restart:
3132         fotg210->async_unlinking = true;
3133         while (fotg210->async_iaa) {
3134                 qh = fotg210->async_iaa;
3135                 fotg210->async_iaa = qh->unlink_next;
3136                 qh->unlink_next = NULL;
3137
3138                 qh->qh_state = QH_STATE_IDLE;
3139                 qh->qh_next.qh = NULL;
3140
3141                 qh_completions(fotg210, qh);
3142                 if (!list_empty(&qh->qtd_list) &&
3143                                 fotg210->rh_state == FOTG210_RH_RUNNING)
3144                         qh_link_async(fotg210, qh);
3145                 disable_async(fotg210);
3146         }
3147         fotg210->async_unlinking = false;
3148
3149         /* Start a new IAA cycle if any QHs are waiting for it */
3150         if (fotg210->async_unlink) {
3151                 start_iaa_cycle(fotg210, true);
3152                 if (unlikely(fotg210->rh_state < FOTG210_RH_RUNNING))
3153                         goto restart;
3154         }
3155 }
3156
3157 static void unlink_empty_async(struct fotg210_hcd *fotg210)
3158 {
3159         struct fotg210_qh *qh, *next;
3160         bool stopped = (fotg210->rh_state < FOTG210_RH_RUNNING);
3161         bool check_unlinks_later = false;
3162
3163         /* Unlink all the async QHs that have been empty for a timer cycle */
3164         next = fotg210->async->qh_next.qh;
3165         while (next) {
3166                 qh = next;
3167                 next = qh->qh_next.qh;
3168
3169                 if (list_empty(&qh->qtd_list) &&
3170                                 qh->qh_state == QH_STATE_LINKED) {
3171                         if (!stopped && qh->unlink_cycle ==
3172                                         fotg210->async_unlink_cycle)
3173                                 check_unlinks_later = true;
3174                         else
3175                                 single_unlink_async(fotg210, qh);
3176                 }
3177         }
3178
3179         /* Start a new IAA cycle if any QHs are waiting for it */
3180         if (fotg210->async_unlink)
3181                 start_iaa_cycle(fotg210, false);
3182
3183         /* QHs that haven't been empty for long enough will be handled later */
3184         if (check_unlinks_later) {
3185                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_ASYNC_UNLINKS,
3186                                 true);
3187                 ++fotg210->async_unlink_cycle;
3188         }
3189 }
3190
3191 /* makes sure the async qh will become idle */
3192 /* caller must own fotg210->lock */
3193
3194 static void start_unlink_async(struct fotg210_hcd *fotg210,
3195                 struct fotg210_qh *qh)
3196 {
3197         /*
3198          * If the QH isn't linked then there's nothing we can do
3199          * unless we were called during a giveback, in which case
3200          * qh_completions() has to deal with it.
3201          */
3202         if (qh->qh_state != QH_STATE_LINKED) {
3203                 if (qh->qh_state == QH_STATE_COMPLETING)
3204                         qh->needs_rescan = 1;
3205                 return;
3206         }
3207
3208         single_unlink_async(fotg210, qh);
3209         start_iaa_cycle(fotg210, false);
3210 }
3211
3212 static void scan_async(struct fotg210_hcd *fotg210)
3213 {
3214         struct fotg210_qh *qh;
3215         bool check_unlinks_later = false;
3216
3217         fotg210->qh_scan_next = fotg210->async->qh_next.qh;
3218         while (fotg210->qh_scan_next) {
3219                 qh = fotg210->qh_scan_next;
3220                 fotg210->qh_scan_next = qh->qh_next.qh;
3221 rescan:
3222                 /* clean any finished work for this qh */
3223                 if (!list_empty(&qh->qtd_list)) {
3224                         int temp;
3225
3226                         /*
3227                          * Unlinks could happen here; completion reporting
3228                          * drops the lock.  That's why fotg210->qh_scan_next
3229                          * always holds the next qh to scan; if the next qh
3230                          * gets unlinked then fotg210->qh_scan_next is adjusted
3231                          * in single_unlink_async().
3232                          */
3233                         temp = qh_completions(fotg210, qh);
3234                         if (qh->needs_rescan) {
3235                                 start_unlink_async(fotg210, qh);
3236                         } else if (list_empty(&qh->qtd_list)
3237                                         && qh->qh_state == QH_STATE_LINKED) {
3238                                 qh->unlink_cycle = fotg210->async_unlink_cycle;
3239                                 check_unlinks_later = true;
3240                         } else if (temp != 0)
3241                                 goto rescan;
3242                 }
3243         }
3244
3245         /*
3246          * Unlink empty entries, reducing DMA usage as well
3247          * as HCD schedule-scanning costs.  Delay for any qh
3248          * we just scanned, there's a not-unusual case that it
3249          * doesn't stay idle for long.
3250          */
3251         if (check_unlinks_later && fotg210->rh_state == FOTG210_RH_RUNNING &&
3252                         !(fotg210->enabled_hrtimer_events &
3253                         BIT(FOTG210_HRTIMER_ASYNC_UNLINKS))) {
3254                 fotg210_enable_event(fotg210,
3255                                 FOTG210_HRTIMER_ASYNC_UNLINKS, true);
3256                 ++fotg210->async_unlink_cycle;
3257         }
3258 }
3259 /* EHCI scheduled transaction support:  interrupt, iso, split iso
3260  * These are called "periodic" transactions in the EHCI spec.
3261  *
3262  * Note that for interrupt transfers, the QH/QTD manipulation is shared
3263  * with the "asynchronous" transaction support (control/bulk transfers).
3264  * The only real difference is in how interrupt transfers are scheduled.
3265  *
3266  * For ISO, we make an "iso_stream" head to serve the same role as a QH.
3267  * It keeps track of every ITD (or SITD) that's linked, and holds enough
3268  * pre-calculated schedule data to make appending to the queue be quick.
3269  */
3270 static int fotg210_get_frame(struct usb_hcd *hcd);
3271
3272 /* periodic_next_shadow - return "next" pointer on shadow list
3273  * @periodic: host pointer to qh/itd
3274  * @tag: hardware tag for type of this record
3275  */
3276 static union fotg210_shadow *periodic_next_shadow(struct fotg210_hcd *fotg210,
3277                 union fotg210_shadow *periodic, __hc32 tag)
3278 {
3279         switch (hc32_to_cpu(fotg210, tag)) {
3280         case Q_TYPE_QH:
3281                 return &periodic->qh->qh_next;
3282         case Q_TYPE_FSTN:
3283                 return &periodic->fstn->fstn_next;
3284         default:
3285                 return &periodic->itd->itd_next;
3286         }
3287 }
3288
3289 static __hc32 *shadow_next_periodic(struct fotg210_hcd *fotg210,
3290                 union fotg210_shadow *periodic, __hc32 tag)
3291 {
3292         switch (hc32_to_cpu(fotg210, tag)) {
3293         /* our fotg210_shadow.qh is actually software part */
3294         case Q_TYPE_QH:
3295                 return &periodic->qh->hw->hw_next;
3296         /* others are hw parts */
3297         default:
3298                 return periodic->hw_next;
3299         }
3300 }
3301
3302 /* caller must hold fotg210->lock */
3303 static void periodic_unlink(struct fotg210_hcd *fotg210, unsigned frame,
3304                 void *ptr)
3305 {
3306         union fotg210_shadow *prev_p = &fotg210->pshadow[frame];
3307         __hc32 *hw_p = &fotg210->periodic[frame];
3308         union fotg210_shadow here = *prev_p;
3309
3310         /* find predecessor of "ptr"; hw and shadow lists are in sync */
3311         while (here.ptr && here.ptr != ptr) {
3312                 prev_p = periodic_next_shadow(fotg210, prev_p,
3313                                 Q_NEXT_TYPE(fotg210, *hw_p));
3314                 hw_p = shadow_next_periodic(fotg210, &here,
3315                                 Q_NEXT_TYPE(fotg210, *hw_p));
3316                 here = *prev_p;
3317         }
3318         /* an interrupt entry (at list end) could have been shared */
3319         if (!here.ptr)
3320                 return;
3321
3322         /* update shadow and hardware lists ... the old "next" pointers
3323          * from ptr may still be in use, the caller updates them.
3324          */
3325         *prev_p = *periodic_next_shadow(fotg210, &here,
3326                         Q_NEXT_TYPE(fotg210, *hw_p));
3327
3328         *hw_p = *shadow_next_periodic(fotg210, &here,
3329                         Q_NEXT_TYPE(fotg210, *hw_p));
3330 }
3331
3332 /* how many of the uframe's 125 usecs are allocated? */
3333 static unsigned short periodic_usecs(struct fotg210_hcd *fotg210,
3334                 unsigned frame, unsigned uframe)
3335 {
3336         __hc32 *hw_p = &fotg210->periodic[frame];
3337         union fotg210_shadow *q = &fotg210->pshadow[frame];
3338         unsigned usecs = 0;
3339         struct fotg210_qh_hw *hw;
3340
3341         while (q->ptr) {
3342                 switch (hc32_to_cpu(fotg210, Q_NEXT_TYPE(fotg210, *hw_p))) {
3343                 case Q_TYPE_QH:
3344                         hw = q->qh->hw;
3345                         /* is it in the S-mask? */
3346                         if (hw->hw_info2 & cpu_to_hc32(fotg210, 1 << uframe))
3347                                 usecs += q->qh->usecs;
3348                         /* ... or C-mask? */
3349                         if (hw->hw_info2 & cpu_to_hc32(fotg210,
3350                                         1 << (8 + uframe)))
3351                                 usecs += q->qh->c_usecs;
3352                         hw_p = &hw->hw_next;
3353                         q = &q->qh->qh_next;
3354                         break;
3355                 /* case Q_TYPE_FSTN: */
3356                 default:
3357                         /* for "save place" FSTNs, count the relevant INTR
3358                          * bandwidth from the previous frame
3359                          */
3360                         if (q->fstn->hw_prev != FOTG210_LIST_END(fotg210))
3361                                 fotg210_dbg(fotg210, "ignoring FSTN cost ...\n");
3362
3363                         hw_p = &q->fstn->hw_next;
3364                         q = &q->fstn->fstn_next;
3365                         break;
3366                 case Q_TYPE_ITD:
3367                         if (q->itd->hw_transaction[uframe])
3368                                 usecs += q->itd->stream->usecs;
3369                         hw_p = &q->itd->hw_next;
3370                         q = &q->itd->itd_next;
3371                         break;
3372                 }
3373         }
3374         if (usecs > fotg210->uframe_periodic_max)
3375                 fotg210_err(fotg210, "uframe %d sched overrun: %d usecs\n",
3376                                 frame * 8 + uframe, usecs);
3377         return usecs;
3378 }
3379
3380 static int same_tt(struct usb_device *dev1, struct usb_device *dev2)
3381 {
3382         if (!dev1->tt || !dev2->tt)
3383                 return 0;
3384         if (dev1->tt != dev2->tt)
3385                 return 0;
3386         if (dev1->tt->multi)
3387                 return dev1->ttport == dev2->ttport;
3388         else
3389                 return 1;
3390 }
3391
3392 /* return true iff the device's transaction translator is available
3393  * for a periodic transfer starting at the specified frame, using
3394  * all the uframes in the mask.
3395  */
3396 static int tt_no_collision(struct fotg210_hcd *fotg210, unsigned period,
3397                 struct usb_device *dev, unsigned frame, u32 uf_mask)
3398 {
3399         if (period == 0)        /* error */
3400                 return 0;
3401
3402         /* note bandwidth wastage:  split never follows csplit
3403          * (different dev or endpoint) until the next uframe.
3404          * calling convention doesn't make that distinction.
3405          */
3406         for (; frame < fotg210->periodic_size; frame += period) {
3407                 union fotg210_shadow here;
3408                 __hc32 type;
3409                 struct fotg210_qh_hw *hw;
3410
3411                 here = fotg210->pshadow[frame];
3412                 type = Q_NEXT_TYPE(fotg210, fotg210->periodic[frame]);
3413                 while (here.ptr) {
3414                         switch (hc32_to_cpu(fotg210, type)) {
3415                         case Q_TYPE_ITD:
3416                                 type = Q_NEXT_TYPE(fotg210, here.itd->hw_next);
3417                                 here = here.itd->itd_next;
3418                                 continue;
3419                         case Q_TYPE_QH:
3420                                 hw = here.qh->hw;
3421                                 if (same_tt(dev, here.qh->dev)) {
3422                                         u32 mask;
3423
3424                                         mask = hc32_to_cpu(fotg210,
3425                                                         hw->hw_info2);
3426                                         /* "knows" no gap is needed */
3427                                         mask |= mask >> 8;
3428                                         if (mask & uf_mask)
3429                                                 break;
3430                                 }
3431                                 type = Q_NEXT_TYPE(fotg210, hw->hw_next);
3432                                 here = here.qh->qh_next;
3433                                 continue;
3434                         /* case Q_TYPE_FSTN: */
3435                         default:
3436                                 fotg210_dbg(fotg210,
3437                                                 "periodic frame %d bogus type %d\n",
3438                                                 frame, type);
3439                         }
3440
3441                         /* collision or error */
3442                         return 0;
3443                 }
3444         }
3445
3446         /* no collision */
3447         return 1;
3448 }
3449
3450 static void enable_periodic(struct fotg210_hcd *fotg210)
3451 {
3452         if (fotg210->periodic_count++)
3453                 return;
3454
3455         /* Stop waiting to turn off the periodic schedule */
3456         fotg210->enabled_hrtimer_events &=
3457                 ~BIT(FOTG210_HRTIMER_DISABLE_PERIODIC);
3458
3459         /* Don't start the schedule until PSS is 0 */
3460         fotg210_poll_PSS(fotg210);
3461         turn_on_io_watchdog(fotg210);
3462 }
3463
3464 static void disable_periodic(struct fotg210_hcd *fotg210)
3465 {
3466         if (--fotg210->periodic_count)
3467                 return;
3468
3469         /* Don't turn off the schedule until PSS is 1 */
3470         fotg210_poll_PSS(fotg210);
3471 }
3472
3473 /* periodic schedule slots have iso tds (normal or split) first, then a
3474  * sparse tree for active interrupt transfers.
3475  *
3476  * this just links in a qh; caller guarantees uframe masks are set right.
3477  * no FSTN support (yet; fotg210 0.96+)
3478  */
3479 static void qh_link_periodic(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3480 {
3481         unsigned i;
3482         unsigned period = qh->period;
3483
3484         dev_dbg(&qh->dev->dev,
3485                         "link qh%d-%04x/%p start %d [%d/%d us]\n", period,
3486                         hc32_to_cpup(fotg210, &qh->hw->hw_info2) &
3487                         (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs,
3488                         qh->c_usecs);
3489
3490         /* high bandwidth, or otherwise every microframe */
3491         if (period == 0)
3492                 period = 1;
3493
3494         for (i = qh->start; i < fotg210->periodic_size; i += period) {
3495                 union fotg210_shadow *prev = &fotg210->pshadow[i];
3496                 __hc32 *hw_p = &fotg210->periodic[i];
3497                 union fotg210_shadow here = *prev;
3498                 __hc32 type = 0;
3499
3500                 /* skip the iso nodes at list head */
3501                 while (here.ptr) {
3502                         type = Q_NEXT_TYPE(fotg210, *hw_p);
3503                         if (type == cpu_to_hc32(fotg210, Q_TYPE_QH))
3504                                 break;
3505                         prev = periodic_next_shadow(fotg210, prev, type);
3506                         hw_p = shadow_next_periodic(fotg210, &here, type);
3507                         here = *prev;
3508                 }
3509
3510                 /* sorting each branch by period (slow-->fast)
3511                  * enables sharing interior tree nodes
3512                  */
3513                 while (here.ptr && qh != here.qh) {
3514                         if (qh->period > here.qh->period)
3515                                 break;
3516                         prev = &here.qh->qh_next;
3517                         hw_p = &here.qh->hw->hw_next;
3518                         here = *prev;
3519                 }
3520                 /* link in this qh, unless some earlier pass did that */
3521                 if (qh != here.qh) {
3522                         qh->qh_next = here;
3523                         if (here.qh)
3524                                 qh->hw->hw_next = *hw_p;
3525                         wmb();
3526                         prev->qh = qh;
3527                         *hw_p = QH_NEXT(fotg210, qh->qh_dma);
3528                 }
3529         }
3530         qh->qh_state = QH_STATE_LINKED;
3531         qh->xacterrs = 0;
3532
3533         /* update per-qh bandwidth for usbfs */
3534         fotg210_to_hcd(fotg210)->self.bandwidth_allocated += qh->period
3535                 ? ((qh->usecs + qh->c_usecs) / qh->period)
3536                 : (qh->usecs * 8);
3537
3538         list_add(&qh->intr_node, &fotg210->intr_qh_list);
3539
3540         /* maybe enable periodic schedule processing */
3541         ++fotg210->intr_count;
3542         enable_periodic(fotg210);
3543 }
3544
3545 static void qh_unlink_periodic(struct fotg210_hcd *fotg210,
3546                 struct fotg210_qh *qh)
3547 {
3548         unsigned i;
3549         unsigned period;
3550
3551         /*
3552          * If qh is for a low/full-speed device, simply unlinking it
3553          * could interfere with an ongoing split transaction.  To unlink
3554          * it safely would require setting the QH_INACTIVATE bit and
3555          * waiting at least one frame, as described in EHCI 4.12.2.5.
3556          *
3557          * We won't bother with any of this.  Instead, we assume that the
3558          * only reason for unlinking an interrupt QH while the current URB
3559          * is still active is to dequeue all the URBs (flush the whole
3560          * endpoint queue).
3561          *
3562          * If rebalancing the periodic schedule is ever implemented, this
3563          * approach will no longer be valid.
3564          */
3565
3566         /* high bandwidth, or otherwise part of every microframe */
3567         period = qh->period;
3568         if (!period)
3569                 period = 1;
3570
3571         for (i = qh->start; i < fotg210->periodic_size; i += period)
3572                 periodic_unlink(fotg210, i, qh);
3573
3574         /* update per-qh bandwidth for usbfs */
3575         fotg210_to_hcd(fotg210)->self.bandwidth_allocated -= qh->period
3576                 ? ((qh->usecs + qh->c_usecs) / qh->period)
3577                 : (qh->usecs * 8);
3578
3579         dev_dbg(&qh->dev->dev,
3580                         "unlink qh%d-%04x/%p start %d [%d/%d us]\n",
3581                         qh->period, hc32_to_cpup(fotg210, &qh->hw->hw_info2) &
3582                         (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs,
3583                         qh->c_usecs);
3584
3585         /* qh->qh_next still "live" to HC */
3586         qh->qh_state = QH_STATE_UNLINK;
3587         qh->qh_next.ptr = NULL;
3588
3589         if (fotg210->qh_scan_next == qh)
3590                 fotg210->qh_scan_next = list_entry(qh->intr_node.next,
3591                                 struct fotg210_qh, intr_node);
3592         list_del(&qh->intr_node);
3593 }
3594
3595 static void start_unlink_intr(struct fotg210_hcd *fotg210,
3596                 struct fotg210_qh *qh)
3597 {
3598         /* If the QH isn't linked then there's nothing we can do
3599          * unless we were called during a giveback, in which case
3600          * qh_completions() has to deal with it.
3601          */
3602         if (qh->qh_state != QH_STATE_LINKED) {
3603                 if (qh->qh_state == QH_STATE_COMPLETING)
3604                         qh->needs_rescan = 1;
3605                 return;
3606         }
3607
3608         qh_unlink_periodic(fotg210, qh);
3609
3610         /* Make sure the unlinks are visible before starting the timer */
3611         wmb();
3612
3613         /*
3614          * The EHCI spec doesn't say how long it takes the controller to
3615          * stop accessing an unlinked interrupt QH.  The timer delay is
3616          * 9 uframes; presumably that will be long enough.
3617          */
3618         qh->unlink_cycle = fotg210->intr_unlink_cycle;
3619
3620         /* New entries go at the end of the intr_unlink list */
3621         if (fotg210->intr_unlink)
3622                 fotg210->intr_unlink_last->unlink_next = qh;
3623         else
3624                 fotg210->intr_unlink = qh;
3625         fotg210->intr_unlink_last = qh;
3626
3627         if (fotg210->intr_unlinking)
3628                 ;       /* Avoid recursive calls */
3629         else if (fotg210->rh_state < FOTG210_RH_RUNNING)
3630                 fotg210_handle_intr_unlinks(fotg210);
3631         else if (fotg210->intr_unlink == qh) {
3632                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_UNLINK_INTR,
3633                                 true);
3634                 ++fotg210->intr_unlink_cycle;
3635         }
3636 }
3637
3638 static void end_unlink_intr(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3639 {
3640         struct fotg210_qh_hw *hw = qh->hw;
3641         int rc;
3642
3643         qh->qh_state = QH_STATE_IDLE;
3644         hw->hw_next = FOTG210_LIST_END(fotg210);
3645
3646         qh_completions(fotg210, qh);
3647
3648         /* reschedule QH iff another request is queued */
3649         if (!list_empty(&qh->qtd_list) &&
3650                         fotg210->rh_state == FOTG210_RH_RUNNING) {
3651                 rc = qh_schedule(fotg210, qh);
3652
3653                 /* An error here likely indicates handshake failure
3654                  * or no space left in the schedule.  Neither fault
3655                  * should happen often ...
3656                  *
3657                  * FIXME kill the now-dysfunctional queued urbs
3658                  */
3659                 if (rc != 0)
3660                         fotg210_err(fotg210, "can't reschedule qh %p, err %d\n",
3661                                         qh, rc);
3662         }
3663
3664         /* maybe turn off periodic schedule */
3665         --fotg210->intr_count;
3666         disable_periodic(fotg210);
3667 }
3668
3669 static int check_period(struct fotg210_hcd *fotg210, unsigned frame,
3670                 unsigned uframe, unsigned period, unsigned usecs)
3671 {
3672         int claimed;
3673
3674         /* complete split running into next frame?
3675          * given FSTN support, we could sometimes check...
3676          */
3677         if (uframe >= 8)
3678                 return 0;
3679
3680         /* convert "usecs we need" to "max already claimed" */
3681         usecs = fotg210->uframe_periodic_max - usecs;
3682
3683         /* we "know" 2 and 4 uframe intervals were rejected; so
3684          * for period 0, check _every_ microframe in the schedule.
3685          */
3686         if (unlikely(period == 0)) {
3687                 do {
3688                         for (uframe = 0; uframe < 7; uframe++) {
3689                                 claimed = periodic_usecs(fotg210, frame,
3690                                                 uframe);
3691                                 if (claimed > usecs)
3692                                         return 0;
3693                         }
3694                 } while ((frame += 1) < fotg210->periodic_size);
3695
3696         /* just check the specified uframe, at that period */
3697         } else {
3698                 do {
3699                         claimed = periodic_usecs(fotg210, frame, uframe);
3700                         if (claimed > usecs)
3701                                 return 0;
3702                 } while ((frame += period) < fotg210->periodic_size);
3703         }
3704
3705         /* success! */
3706         return 1;
3707 }
3708
3709 static int check_intr_schedule(struct fotg210_hcd *fotg210, unsigned frame,
3710                 unsigned uframe, const struct fotg210_qh *qh, __hc32 *c_maskp)
3711 {
3712         int retval = -ENOSPC;
3713         u8 mask = 0;
3714
3715         if (qh->c_usecs && uframe >= 6)         /* FSTN territory? */
3716                 goto done;
3717
3718         if (!check_period(fotg210, frame, uframe, qh->period, qh->usecs))
3719                 goto done;
3720         if (!qh->c_usecs) {
3721                 retval = 0;
3722                 *c_maskp = 0;
3723                 goto done;
3724         }
3725
3726         /* Make sure this tt's buffer is also available for CSPLITs.
3727          * We pessimize a bit; probably the typical full speed case
3728          * doesn't need the second CSPLIT.
3729          *
3730          * NOTE:  both SPLIT and CSPLIT could be checked in just
3731          * one smart pass...
3732          */
3733         mask = 0x03 << (uframe + qh->gap_uf);
3734         *c_maskp = cpu_to_hc32(fotg210, mask << 8);
3735
3736         mask |= 1 << uframe;
3737         if (tt_no_collision(fotg210, qh->period, qh->dev, frame, mask)) {
3738                 if (!check_period(fotg210, frame, uframe + qh->gap_uf + 1,
3739                                 qh->period, qh->c_usecs))
3740                         goto done;
3741                 if (!check_period(fotg210, frame, uframe + qh->gap_uf,
3742                                 qh->period, qh->c_usecs))
3743                         goto done;
3744                 retval = 0;
3745         }
3746 done:
3747         return retval;
3748 }
3749
3750 /* "first fit" scheduling policy used the first time through,
3751  * or when the previous schedule slot can't be re-used.
3752  */
3753 static int qh_schedule(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3754 {
3755         int status;
3756         unsigned uframe;
3757         __hc32 c_mask;
3758         unsigned frame; /* 0..(qh->period - 1), or NO_FRAME */
3759         struct fotg210_qh_hw *hw = qh->hw;
3760
3761         qh_refresh(fotg210, qh);
3762         hw->hw_next = FOTG210_LIST_END(fotg210);
3763         frame = qh->start;
3764
3765         /* reuse the previous schedule slots, if we can */
3766         if (frame < qh->period) {
3767                 uframe = ffs(hc32_to_cpup(fotg210, &hw->hw_info2) & QH_SMASK);
3768                 status = check_intr_schedule(fotg210, frame, --uframe,
3769                                 qh, &c_mask);
3770         } else {
3771                 uframe = 0;
3772                 c_mask = 0;
3773                 status = -ENOSPC;
3774         }
3775
3776         /* else scan the schedule to find a group of slots such that all
3777          * uframes have enough periodic bandwidth available.
3778          */
3779         if (status) {
3780                 /* "normal" case, uframing flexible except with splits */
3781                 if (qh->period) {
3782                         int i;
3783
3784                         for (i = qh->period; status && i > 0; --i) {
3785                                 frame = ++fotg210->random_frame % qh->period;
3786                                 for (uframe = 0; uframe < 8; uframe++) {
3787                                         status = check_intr_schedule(fotg210,
3788                                                         frame, uframe, qh,
3789                                                         &c_mask);
3790                                         if (status == 0)
3791                                                 break;
3792                                 }
3793                         }
3794
3795                 /* qh->period == 0 means every uframe */
3796                 } else {
3797                         frame = 0;
3798                         status = check_intr_schedule(fotg210, 0, 0, qh,
3799                                         &c_mask);
3800                 }
3801                 if (status)
3802                         goto done;
3803                 qh->start = frame;
3804
3805                 /* reset S-frame and (maybe) C-frame masks */
3806                 hw->hw_info2 &= cpu_to_hc32(fotg210, ~(QH_CMASK | QH_SMASK));
3807                 hw->hw_info2 |= qh->period
3808                         ? cpu_to_hc32(fotg210, 1 << uframe)
3809                         : cpu_to_hc32(fotg210, QH_SMASK);
3810                 hw->hw_info2 |= c_mask;
3811         } else
3812                 fotg210_dbg(fotg210, "reused qh %p schedule\n", qh);
3813
3814         /* stuff into the periodic schedule */
3815         qh_link_periodic(fotg210, qh);
3816 done:
3817         return status;
3818 }
3819
3820 static int intr_submit(struct fotg210_hcd *fotg210, struct urb *urb,
3821                 struct list_head *qtd_list, gfp_t mem_flags)
3822 {
3823         unsigned epnum;
3824         unsigned long flags;
3825         struct fotg210_qh *qh;
3826         int status;
3827         struct list_head empty;
3828
3829         /* get endpoint and transfer/schedule data */
3830         epnum = urb->ep->desc.bEndpointAddress;
3831
3832         spin_lock_irqsave(&fotg210->lock, flags);
3833
3834         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
3835                 status = -ESHUTDOWN;
3836                 goto done_not_linked;
3837         }
3838         status = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
3839         if (unlikely(status))
3840                 goto done_not_linked;
3841
3842         /* get qh and force any scheduling errors */
3843         INIT_LIST_HEAD(&empty);
3844         qh = qh_append_tds(fotg210, urb, &empty, epnum, &urb->ep->hcpriv);
3845         if (qh == NULL) {
3846                 status = -ENOMEM;
3847                 goto done;
3848         }
3849         if (qh->qh_state == QH_STATE_IDLE) {
3850                 status = qh_schedule(fotg210, qh);
3851                 if (status)
3852                         goto done;
3853         }
3854
3855         /* then queue the urb's tds to the qh */
3856         qh = qh_append_tds(fotg210, urb, qtd_list, epnum, &urb->ep->hcpriv);
3857         BUG_ON(qh == NULL);
3858
3859         /* ... update usbfs periodic stats */
3860         fotg210_to_hcd(fotg210)->self.bandwidth_int_reqs++;
3861
3862 done:
3863         if (unlikely(status))
3864                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
3865 done_not_linked:
3866         spin_unlock_irqrestore(&fotg210->lock, flags);
3867         if (status)
3868                 qtd_list_free(fotg210, urb, qtd_list);
3869
3870         return status;
3871 }
3872
3873 static void scan_intr(struct fotg210_hcd *fotg210)
3874 {
3875         struct fotg210_qh *qh;
3876
3877         list_for_each_entry_safe(qh, fotg210->qh_scan_next,
3878                         &fotg210->intr_qh_list, intr_node) {
3879 rescan:
3880                 /* clean any finished work for this qh */
3881                 if (!list_empty(&qh->qtd_list)) {
3882                         int temp;
3883
3884                         /*
3885                          * Unlinks could happen here; completion reporting
3886                          * drops the lock.  That's why fotg210->qh_scan_next
3887                          * always holds the next qh to scan; if the next qh
3888                          * gets unlinked then fotg210->qh_scan_next is adjusted
3889                          * in qh_unlink_periodic().
3890                          */
3891                         temp = qh_completions(fotg210, qh);
3892                         if (unlikely(qh->needs_rescan ||
3893                                         (list_empty(&qh->qtd_list) &&
3894                                         qh->qh_state == QH_STATE_LINKED)))
3895                                 start_unlink_intr(fotg210, qh);
3896                         else if (temp != 0)
3897                                 goto rescan;
3898                 }
3899         }
3900 }
3901
3902 /* fotg210_iso_stream ops work with both ITD and SITD */
3903
3904 static struct fotg210_iso_stream *iso_stream_alloc(gfp_t mem_flags)
3905 {
3906         struct fotg210_iso_stream *stream;
3907
3908         stream = kzalloc(sizeof(*stream), mem_flags);
3909         if (likely(stream != NULL)) {
3910                 INIT_LIST_HEAD(&stream->td_list);
3911                 INIT_LIST_HEAD(&stream->free_list);
3912                 stream->next_uframe = -1;
3913         }
3914         return stream;
3915 }
3916
3917 static void iso_stream_init(struct fotg210_hcd *fotg210,
3918                 struct fotg210_iso_stream *stream, struct usb_device *dev,
3919                 int pipe, unsigned interval)
3920 {
3921         u32 buf1;
3922         unsigned epnum, maxp;
3923         int is_input;
3924         long bandwidth;
3925         unsigned multi;
3926         struct usb_host_endpoint *ep;
3927
3928         /*
3929          * this might be a "high bandwidth" highspeed endpoint,
3930          * as encoded in the ep descriptor's wMaxPacket field
3931          */
3932         epnum = usb_pipeendpoint(pipe);
3933         is_input = usb_pipein(pipe) ? USB_DIR_IN : 0;
3934         ep = usb_pipe_endpoint(dev, pipe);
3935         maxp = usb_endpoint_maxp(&ep->desc);
3936         if (is_input)
3937                 buf1 = (1 << 11);
3938         else
3939                 buf1 = 0;
3940
3941         multi = usb_endpoint_maxp_mult(&ep->desc);
3942         buf1 |= maxp;
3943         maxp *= multi;
3944
3945         stream->buf0 = cpu_to_hc32(fotg210, (epnum << 8) | dev->devnum);
3946         stream->buf1 = cpu_to_hc32(fotg210, buf1);
3947         stream->buf2 = cpu_to_hc32(fotg210, multi);
3948
3949         /* usbfs wants to report the average usecs per frame tied up
3950          * when transfers on this endpoint are scheduled ...
3951          */
3952         if (dev->speed == USB_SPEED_FULL) {
3953                 interval <<= 3;
3954                 stream->usecs = NS_TO_US(usb_calc_bus_time(dev->speed,
3955                                 is_input, 1, maxp));
3956                 stream->usecs /= 8;
3957         } else {
3958                 stream->highspeed = 1;
3959                 stream->usecs = HS_USECS_ISO(maxp);
3960         }
3961         bandwidth = stream->usecs * 8;
3962         bandwidth /= interval;
3963
3964         stream->bandwidth = bandwidth;
3965         stream->udev = dev;
3966         stream->bEndpointAddress = is_input | epnum;
3967         stream->interval = interval;
3968         stream->maxp = maxp;
3969 }
3970
3971 static struct fotg210_iso_stream *iso_stream_find(struct fotg210_hcd *fotg210,
3972                 struct urb *urb)
3973 {
3974         unsigned epnum;
3975         struct fotg210_iso_stream *stream;
3976         struct usb_host_endpoint *ep;
3977         unsigned long flags;
3978
3979         epnum = usb_pipeendpoint(urb->pipe);
3980         if (usb_pipein(urb->pipe))
3981                 ep = urb->dev->ep_in[epnum];
3982         else
3983                 ep = urb->dev->ep_out[epnum];
3984
3985         spin_lock_irqsave(&fotg210->lock, flags);
3986         stream = ep->hcpriv;
3987
3988         if (unlikely(stream == NULL)) {
3989                 stream = iso_stream_alloc(GFP_ATOMIC);
3990                 if (likely(stream != NULL)) {
3991                         ep->hcpriv = stream;
3992                         stream->ep = ep;
3993                         iso_stream_init(fotg210, stream, urb->dev, urb->pipe,
3994                                         urb->interval);
3995                 }
3996
3997         /* if dev->ep[epnum] is a QH, hw is set */
3998         } else if (unlikely(stream->hw != NULL)) {
3999                 fotg210_dbg(fotg210, "dev %s ep%d%s, not iso??\n",
4000                                 urb->dev->devpath, epnum,
4001                                 usb_pipein(urb->pipe) ? "in" : "out");
4002                 stream = NULL;
4003         }
4004
4005         spin_unlock_irqrestore(&fotg210->lock, flags);
4006         return stream;
4007 }
4008
4009 /* fotg210_iso_sched ops can be ITD-only or SITD-only */
4010
4011 static struct fotg210_iso_sched *iso_sched_alloc(unsigned packets,
4012                 gfp_t mem_flags)
4013 {
4014         struct fotg210_iso_sched *iso_sched;
4015         int size = sizeof(*iso_sched);
4016
4017         size += packets * sizeof(struct fotg210_iso_packet);
4018         iso_sched = kzalloc(size, mem_flags);
4019         if (likely(iso_sched != NULL))
4020                 INIT_LIST_HEAD(&iso_sched->td_list);
4021
4022         return iso_sched;
4023 }
4024
4025 static inline void itd_sched_init(struct fotg210_hcd *fotg210,
4026                 struct fotg210_iso_sched *iso_sched,
4027                 struct fotg210_iso_stream *stream, struct urb *urb)
4028 {
4029         unsigned i;
4030         dma_addr_t dma = urb->transfer_dma;
4031
4032         /* how many uframes are needed for these transfers */
4033         iso_sched->span = urb->number_of_packets * stream->interval;
4034
4035         /* figure out per-uframe itd fields that we'll need later
4036          * when we fit new itds into the schedule.
4037          */
4038         for (i = 0; i < urb->number_of_packets; i++) {
4039                 struct fotg210_iso_packet *uframe = &iso_sched->packet[i];
4040                 unsigned length;
4041                 dma_addr_t buf;
4042                 u32 trans;
4043
4044                 length = urb->iso_frame_desc[i].length;
4045                 buf = dma + urb->iso_frame_desc[i].offset;
4046
4047                 trans = FOTG210_ISOC_ACTIVE;
4048                 trans |= buf & 0x0fff;
4049                 if (unlikely(((i + 1) == urb->number_of_packets))
4050                                 && !(urb->transfer_flags & URB_NO_INTERRUPT))
4051                         trans |= FOTG210_ITD_IOC;
4052                 trans |= length << 16;
4053                 uframe->transaction = cpu_to_hc32(fotg210, trans);
4054
4055                 /* might need to cross a buffer page within a uframe */
4056                 uframe->bufp = (buf & ~(u64)0x0fff);
4057                 buf += length;
4058                 if (unlikely((uframe->bufp != (buf & ~(u64)0x0fff))))
4059                         uframe->cross = 1;
4060         }
4061 }
4062
4063 static void iso_sched_free(struct fotg210_iso_stream *stream,
4064                 struct fotg210_iso_sched *iso_sched)
4065 {
4066         if (!iso_sched)
4067                 return;
4068         /* caller must hold fotg210->lock!*/
4069         list_splice(&iso_sched->td_list, &stream->free_list);
4070         kfree(iso_sched);
4071 }
4072
4073 static int itd_urb_transaction(struct fotg210_iso_stream *stream,
4074                 struct fotg210_hcd *fotg210, struct urb *urb, gfp_t mem_flags)
4075 {
4076         struct fotg210_itd *itd;
4077         dma_addr_t itd_dma;
4078         int i;
4079         unsigned num_itds;
4080         struct fotg210_iso_sched *sched;
4081         unsigned long flags;
4082
4083         sched = iso_sched_alloc(urb->number_of_packets, mem_flags);
4084         if (unlikely(sched == NULL))
4085                 return -ENOMEM;
4086
4087         itd_sched_init(fotg210, sched, stream, urb);
4088
4089         if (urb->interval < 8)
4090                 num_itds = 1 + (sched->span + 7) / 8;
4091         else
4092                 num_itds = urb->number_of_packets;
4093
4094         /* allocate/init ITDs */
4095         spin_lock_irqsave(&fotg210->lock, flags);
4096         for (i = 0; i < num_itds; i++) {
4097
4098                 /*
4099                  * Use iTDs from the free list, but not iTDs that may
4100                  * still be in use by the hardware.
4101                  */
4102                 if (likely(!list_empty(&stream->free_list))) {
4103                         itd = list_first_entry(&stream->free_list,
4104                                         struct fotg210_itd, itd_list);
4105                         if (itd->frame == fotg210->now_frame)
4106                                 goto alloc_itd;
4107                         list_del(&itd->itd_list);
4108                         itd_dma = itd->itd_dma;
4109                 } else {
4110 alloc_itd:
4111                         spin_unlock_irqrestore(&fotg210->lock, flags);
4112                         itd = dma_pool_zalloc(fotg210->itd_pool, mem_flags,
4113                                         &itd_dma);
4114                         spin_lock_irqsave(&fotg210->lock, flags);
4115                         if (!itd) {
4116                                 iso_sched_free(stream, sched);
4117                                 spin_unlock_irqrestore(&fotg210->lock, flags);
4118                                 return -ENOMEM;
4119                         }
4120                 }
4121
4122                 itd->itd_dma = itd_dma;
4123                 list_add(&itd->itd_list, &sched->td_list);
4124         }
4125         spin_unlock_irqrestore(&fotg210->lock, flags);
4126
4127         /* temporarily store schedule info in hcpriv */
4128         urb->hcpriv = sched;
4129         urb->error_count = 0;
4130         return 0;
4131 }
4132
4133 static inline int itd_slot_ok(struct fotg210_hcd *fotg210, u32 mod, u32 uframe,
4134                 u8 usecs, u32 period)
4135 {
4136         uframe %= period;
4137         do {
4138                 /* can't commit more than uframe_periodic_max usec */
4139                 if (periodic_usecs(fotg210, uframe >> 3, uframe & 0x7)
4140                                 > (fotg210->uframe_periodic_max - usecs))
4141                         return 0;
4142
4143                 /* we know urb->interval is 2^N uframes */
4144                 uframe += period;
4145         } while (uframe < mod);
4146         return 1;
4147 }
4148
4149 /* This scheduler plans almost as far into the future as it has actual
4150  * periodic schedule slots.  (Affected by TUNE_FLS, which defaults to
4151  * "as small as possible" to be cache-friendlier.)  That limits the size
4152  * transfers you can stream reliably; avoid more than 64 msec per urb.
4153  * Also avoid queue depths of less than fotg210's worst irq latency (affected
4154  * by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter,
4155  * and other factors); or more than about 230 msec total (for portability,
4156  * given FOTG210_TUNE_FLS and the slop).  Or, write a smarter scheduler!
4157  */
4158
4159 #define SCHEDULE_SLOP 80 /* microframes */
4160
4161 static int iso_stream_schedule(struct fotg210_hcd *fotg210, struct urb *urb,
4162                 struct fotg210_iso_stream *stream)
4163 {
4164         u32 now, next, start, period, span;
4165         int status;
4166         unsigned mod = fotg210->periodic_size << 3;
4167         struct fotg210_iso_sched *sched = urb->hcpriv;
4168
4169         period = urb->interval;
4170         span = sched->span;
4171
4172         if (span > mod - SCHEDULE_SLOP) {
4173                 fotg210_dbg(fotg210, "iso request %p too long\n", urb);
4174                 status = -EFBIG;
4175                 goto fail;
4176         }
4177
4178         now = fotg210_read_frame_index(fotg210) & (mod - 1);
4179
4180         /* Typical case: reuse current schedule, stream is still active.
4181          * Hopefully there are no gaps from the host falling behind
4182          * (irq delays etc), but if there are we'll take the next
4183          * slot in the schedule, implicitly assuming URB_ISO_ASAP.
4184          */
4185         if (likely(!list_empty(&stream->td_list))) {
4186                 u32 excess;
4187
4188                 /* For high speed devices, allow scheduling within the
4189                  * isochronous scheduling threshold.  For full speed devices
4190                  * and Intel PCI-based controllers, don't (work around for
4191                  * Intel ICH9 bug).
4192                  */
4193                 if (!stream->highspeed && fotg210->fs_i_thresh)
4194                         next = now + fotg210->i_thresh;
4195                 else
4196                         next = now;
4197
4198                 /* Fell behind (by up to twice the slop amount)?
4199                  * We decide based on the time of the last currently-scheduled
4200                  * slot, not the time of the next available slot.
4201                  */
4202                 excess = (stream->next_uframe - period - next) & (mod - 1);
4203                 if (excess >= mod - 2 * SCHEDULE_SLOP)
4204                         start = next + excess - mod + period *
4205                                         DIV_ROUND_UP(mod - excess, period);
4206                 else
4207                         start = next + excess + period;
4208                 if (start - now >= mod) {
4209                         fotg210_dbg(fotg210, "request %p would overflow (%d+%d >= %d)\n",
4210                                         urb, start - now - period, period,
4211                                         mod);
4212                         status = -EFBIG;
4213                         goto fail;
4214                 }
4215         }
4216
4217         /* need to schedule; when's the next (u)frame we could start?
4218          * this is bigger than fotg210->i_thresh allows; scheduling itself
4219          * isn't free, the slop should handle reasonably slow cpus.  it
4220          * can also help high bandwidth if the dma and irq loads don't
4221          * jump until after the queue is primed.
4222          */
4223         else {
4224                 int done = 0;
4225
4226                 start = SCHEDULE_SLOP + (now & ~0x07);
4227
4228                 /* NOTE:  assumes URB_ISO_ASAP, to limit complexity/bugs */
4229
4230                 /* find a uframe slot with enough bandwidth.
4231                  * Early uframes are more precious because full-speed
4232                  * iso IN transfers can't use late uframes,
4233                  * and therefore they should be allocated last.
4234                  */
4235                 next = start;
4236                 start += period;
4237                 do {
4238                         start--;
4239                         /* check schedule: enough space? */
4240                         if (itd_slot_ok(fotg210, mod, start,
4241                                         stream->usecs, period))
4242                                 done = 1;
4243                 } while (start > next && !done);
4244
4245                 /* no room in the schedule */
4246                 if (!done) {
4247                         fotg210_dbg(fotg210, "iso resched full %p (now %d max %d)\n",
4248                                         urb, now, now + mod);
4249                         status = -ENOSPC;
4250                         goto fail;
4251                 }
4252         }
4253
4254         /* Tried to schedule too far into the future? */
4255         if (unlikely(start - now + span - period >=
4256                         mod - 2 * SCHEDULE_SLOP)) {
4257                 fotg210_dbg(fotg210, "request %p would overflow (%d+%d >= %d)\n",
4258                                 urb, start - now, span - period,
4259                                 mod - 2 * SCHEDULE_SLOP);
4260                 status = -EFBIG;
4261                 goto fail;
4262         }
4263
4264         stream->next_uframe = start & (mod - 1);
4265
4266         /* report high speed start in uframes; full speed, in frames */
4267         urb->start_frame = stream->next_uframe;
4268         if (!stream->highspeed)
4269                 urb->start_frame >>= 3;
4270
4271         /* Make sure scan_isoc() sees these */
4272         if (fotg210->isoc_count == 0)
4273                 fotg210->next_frame = now >> 3;
4274         return 0;
4275
4276 fail:
4277         iso_sched_free(stream, sched);
4278         urb->hcpriv = NULL;
4279         return status;
4280 }
4281
4282 static inline void itd_init(struct fotg210_hcd *fotg210,
4283                 struct fotg210_iso_stream *stream, struct fotg210_itd *itd)
4284 {
4285         int i;
4286
4287         /* it's been recently zeroed */
4288         itd->hw_next = FOTG210_LIST_END(fotg210);
4289         itd->hw_bufp[0] = stream->buf0;
4290         itd->hw_bufp[1] = stream->buf1;
4291         itd->hw_bufp[2] = stream->buf2;
4292
4293         for (i = 0; i < 8; i++)
4294                 itd->index[i] = -1;
4295
4296         /* All other fields are filled when scheduling */
4297 }
4298
4299 static inline void itd_patch(struct fotg210_hcd *fotg210,
4300                 struct fotg210_itd *itd, struct fotg210_iso_sched *iso_sched,
4301                 unsigned index, u16 uframe)
4302 {
4303         struct fotg210_iso_packet *uf = &iso_sched->packet[index];
4304         unsigned pg = itd->pg;
4305
4306         uframe &= 0x07;
4307         itd->index[uframe] = index;
4308
4309         itd->hw_transaction[uframe] = uf->transaction;
4310         itd->hw_transaction[uframe] |= cpu_to_hc32(fotg210, pg << 12);
4311         itd->hw_bufp[pg] |= cpu_to_hc32(fotg210, uf->bufp & ~(u32)0);
4312         itd->hw_bufp_hi[pg] |= cpu_to_hc32(fotg210, (u32)(uf->bufp >> 32));
4313
4314         /* iso_frame_desc[].offset must be strictly increasing */
4315         if (unlikely(uf->cross)) {
4316                 u64 bufp = uf->bufp + 4096;
4317
4318                 itd->pg = ++pg;
4319                 itd->hw_bufp[pg] |= cpu_to_hc32(fotg210, bufp & ~(u32)0);
4320                 itd->hw_bufp_hi[pg] |= cpu_to_hc32(fotg210, (u32)(bufp >> 32));
4321         }
4322 }
4323
4324 static inline void itd_link(struct fotg210_hcd *fotg210, unsigned frame,
4325                 struct fotg210_itd *itd)
4326 {
4327         union fotg210_shadow *prev = &fotg210->pshadow[frame];
4328         __hc32 *hw_p = &fotg210->periodic[frame];
4329         union fotg210_shadow here = *prev;
4330         __hc32 type = 0;
4331
4332         /* skip any iso nodes which might belong to previous microframes */
4333         while (here.ptr) {
4334                 type = Q_NEXT_TYPE(fotg210, *hw_p);
4335                 if (type == cpu_to_hc32(fotg210, Q_TYPE_QH))
4336                         break;
4337                 prev = periodic_next_shadow(fotg210, prev, type);
4338                 hw_p = shadow_next_periodic(fotg210, &here, type);
4339                 here = *prev;
4340         }
4341
4342         itd->itd_next = here;
4343         itd->hw_next = *hw_p;
4344         prev->itd = itd;
4345         itd->frame = frame;
4346         wmb();
4347         *hw_p = cpu_to_hc32(fotg210, itd->itd_dma | Q_TYPE_ITD);
4348 }
4349
4350 /* fit urb's itds into the selected schedule slot; activate as needed */
4351 static void itd_link_urb(struct fotg210_hcd *fotg210, struct urb *urb,
4352                 unsigned mod, struct fotg210_iso_stream *stream)
4353 {
4354         int packet;
4355         unsigned next_uframe, uframe, frame;
4356         struct fotg210_iso_sched *iso_sched = urb->hcpriv;
4357         struct fotg210_itd *itd;
4358
4359         next_uframe = stream->next_uframe & (mod - 1);
4360
4361         if (unlikely(list_empty(&stream->td_list))) {
4362                 fotg210_to_hcd(fotg210)->self.bandwidth_allocated
4363                                 += stream->bandwidth;
4364                 fotg210_dbg(fotg210,
4365                         "schedule devp %s ep%d%s-iso period %d start %d.%d\n",
4366                         urb->dev->devpath, stream->bEndpointAddress & 0x0f,
4367                         (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
4368                         urb->interval,
4369                         next_uframe >> 3, next_uframe & 0x7);
4370         }
4371
4372         /* fill iTDs uframe by uframe */
4373         for (packet = 0, itd = NULL; packet < urb->number_of_packets;) {
4374                 if (itd == NULL) {
4375                         /* ASSERT:  we have all necessary itds */
4376
4377                         /* ASSERT:  no itds for this endpoint in this uframe */
4378
4379                         itd = list_entry(iso_sched->td_list.next,
4380                                         struct fotg210_itd, itd_list);
4381                         list_move_tail(&itd->itd_list, &stream->td_list);
4382                         itd->stream = stream;
4383                         itd->urb = urb;
4384                         itd_init(fotg210, stream, itd);
4385                 }
4386
4387                 uframe = next_uframe & 0x07;
4388                 frame = next_uframe >> 3;
4389
4390                 itd_patch(fotg210, itd, iso_sched, packet, uframe);
4391
4392                 next_uframe += stream->interval;
4393                 next_uframe &= mod - 1;
4394                 packet++;
4395
4396                 /* link completed itds into the schedule */
4397                 if (((next_uframe >> 3) != frame)
4398                                 || packet == urb->number_of_packets) {
4399                         itd_link(fotg210, frame & (fotg210->periodic_size - 1),
4400                                         itd);
4401                         itd = NULL;
4402                 }
4403         }
4404         stream->next_uframe = next_uframe;
4405
4406         /* don't need that schedule data any more */
4407         iso_sched_free(stream, iso_sched);
4408         urb->hcpriv = NULL;
4409
4410         ++fotg210->isoc_count;
4411         enable_periodic(fotg210);
4412 }
4413
4414 #define ISO_ERRS (FOTG210_ISOC_BUF_ERR | FOTG210_ISOC_BABBLE |\
4415                 FOTG210_ISOC_XACTERR)
4416
4417 /* Process and recycle a completed ITD.  Return true iff its urb completed,
4418  * and hence its completion callback probably added things to the hardware
4419  * schedule.
4420  *
4421  * Note that we carefully avoid recycling this descriptor until after any
4422  * completion callback runs, so that it won't be reused quickly.  That is,
4423  * assuming (a) no more than two urbs per frame on this endpoint, and also
4424  * (b) only this endpoint's completions submit URBs.  It seems some silicon
4425  * corrupts things if you reuse completed descriptors very quickly...
4426  */
4427 static bool itd_complete(struct fotg210_hcd *fotg210, struct fotg210_itd *itd)
4428 {
4429         struct urb *urb = itd->urb;
4430         struct usb_iso_packet_descriptor *desc;
4431         u32 t;
4432         unsigned uframe;
4433         int urb_index = -1;
4434         struct fotg210_iso_stream *stream = itd->stream;
4435         struct usb_device *dev;
4436         bool retval = false;
4437
4438         /* for each uframe with a packet */
4439         for (uframe = 0; uframe < 8; uframe++) {
4440                 if (likely(itd->index[uframe] == -1))
4441                         continue;
4442                 urb_index = itd->index[uframe];
4443                 desc = &urb->iso_frame_desc[urb_index];
4444
4445                 t = hc32_to_cpup(fotg210, &itd->hw_transaction[uframe]);
4446                 itd->hw_transaction[uframe] = 0;
4447
4448                 /* report transfer status */
4449                 if (unlikely(t & ISO_ERRS)) {
4450                         urb->error_count++;
4451                         if (t & FOTG210_ISOC_BUF_ERR)
4452                                 desc->status = usb_pipein(urb->pipe)
4453                                         ? -ENOSR  /* hc couldn't read */
4454                                         : -ECOMM; /* hc couldn't write */
4455                         else if (t & FOTG210_ISOC_BABBLE)
4456                                 desc->status = -EOVERFLOW;
4457                         else /* (t & FOTG210_ISOC_XACTERR) */
4458                                 desc->status = -EPROTO;
4459
4460                         /* HC need not update length with this error */
4461                         if (!(t & FOTG210_ISOC_BABBLE)) {
4462                                 desc->actual_length = FOTG210_ITD_LENGTH(t);
4463                                 urb->actual_length += desc->actual_length;
4464                         }
4465                 } else if (likely((t & FOTG210_ISOC_ACTIVE) == 0)) {
4466                         desc->status = 0;
4467                         desc->actual_length = FOTG210_ITD_LENGTH(t);
4468                         urb->actual_length += desc->actual_length;
4469                 } else {
4470                         /* URB was too late */
4471                         desc->status = -EXDEV;
4472                 }
4473         }
4474
4475         /* handle completion now? */
4476         if (likely((urb_index + 1) != urb->number_of_packets))
4477                 goto done;
4478
4479         /* ASSERT: it's really the last itd for this urb
4480          * list_for_each_entry (itd, &stream->td_list, itd_list)
4481          *      BUG_ON (itd->urb == urb);
4482          */
4483
4484         /* give urb back to the driver; completion often (re)submits */
4485         dev = urb->dev;
4486         fotg210_urb_done(fotg210, urb, 0);
4487         retval = true;
4488         urb = NULL;
4489
4490         --fotg210->isoc_count;
4491         disable_periodic(fotg210);
4492
4493         if (unlikely(list_is_singular(&stream->td_list))) {
4494                 fotg210_to_hcd(fotg210)->self.bandwidth_allocated
4495                                 -= stream->bandwidth;
4496                 fotg210_dbg(fotg210,
4497                         "deschedule devp %s ep%d%s-iso\n",
4498                         dev->devpath, stream->bEndpointAddress & 0x0f,
4499                         (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
4500         }
4501
4502 done:
4503         itd->urb = NULL;
4504
4505         /* Add to the end of the free list for later reuse */
4506         list_move_tail(&itd->itd_list, &stream->free_list);
4507
4508         /* Recycle the iTDs when the pipeline is empty (ep no longer in use) */
4509         if (list_empty(&stream->td_list)) {
4510                 list_splice_tail_init(&stream->free_list,
4511                                 &fotg210->cached_itd_list);
4512                 start_free_itds(fotg210);
4513         }
4514
4515         return retval;
4516 }
4517
4518 static int itd_submit(struct fotg210_hcd *fotg210, struct urb *urb,
4519                 gfp_t mem_flags)
4520 {
4521         int status = -EINVAL;
4522         unsigned long flags;
4523         struct fotg210_iso_stream *stream;
4524
4525         /* Get iso_stream head */
4526         stream = iso_stream_find(fotg210, urb);
4527         if (unlikely(stream == NULL)) {
4528                 fotg210_dbg(fotg210, "can't get iso stream\n");
4529                 return -ENOMEM;
4530         }
4531         if (unlikely(urb->interval != stream->interval &&
4532                         fotg210_port_speed(fotg210, 0) ==
4533                         USB_PORT_STAT_HIGH_SPEED)) {
4534                 fotg210_dbg(fotg210, "can't change iso interval %d --> %d\n",
4535                                 stream->interval, urb->interval);
4536                 goto done;
4537         }
4538
4539 #ifdef FOTG210_URB_TRACE
4540         fotg210_dbg(fotg210,
4541                         "%s %s urb %p ep%d%s len %d, %d pkts %d uframes[%p]\n",
4542                         __func__, urb->dev->devpath, urb,
4543                         usb_pipeendpoint(urb->pipe),
4544                         usb_pipein(urb->pipe) ? "in" : "out",
4545                         urb->transfer_buffer_length,
4546                         urb->number_of_packets, urb->interval,
4547                         stream);
4548 #endif
4549
4550         /* allocate ITDs w/o locking anything */
4551         status = itd_urb_transaction(stream, fotg210, urb, mem_flags);
4552         if (unlikely(status < 0)) {
4553                 fotg210_dbg(fotg210, "can't init itds\n");
4554                 goto done;
4555         }
4556
4557         /* schedule ... need to lock */
4558         spin_lock_irqsave(&fotg210->lock, flags);
4559         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
4560                 status = -ESHUTDOWN;
4561                 goto done_not_linked;
4562         }
4563         status = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
4564         if (unlikely(status))
4565                 goto done_not_linked;
4566         status = iso_stream_schedule(fotg210, urb, stream);
4567         if (likely(status == 0))
4568                 itd_link_urb(fotg210, urb, fotg210->periodic_size << 3, stream);
4569         else
4570                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
4571 done_not_linked:
4572         spin_unlock_irqrestore(&fotg210->lock, flags);
4573 done:
4574         return status;
4575 }
4576
4577 static inline int scan_frame_queue(struct fotg210_hcd *fotg210, unsigned frame,
4578                 unsigned now_frame, bool live)
4579 {
4580         unsigned uf;
4581         bool modified;
4582         union fotg210_shadow q, *q_p;
4583         __hc32 type, *hw_p;
4584
4585         /* scan each element in frame's queue for completions */
4586         q_p = &fotg210->pshadow[frame];
4587         hw_p = &fotg210->periodic[frame];
4588         q.ptr = q_p->ptr;
4589         type = Q_NEXT_TYPE(fotg210, *hw_p);
4590         modified = false;
4591
4592         while (q.ptr) {
4593                 switch (hc32_to_cpu(fotg210, type)) {
4594                 case Q_TYPE_ITD:
4595                         /* If this ITD is still active, leave it for
4596                          * later processing ... check the next entry.
4597                          * No need to check for activity unless the
4598                          * frame is current.
4599                          */
4600                         if (frame == now_frame && live) {
4601                                 rmb();
4602                                 for (uf = 0; uf < 8; uf++) {
4603                                         if (q.itd->hw_transaction[uf] &
4604                                                         ITD_ACTIVE(fotg210))
4605                                                 break;
4606                                 }
4607                                 if (uf < 8) {
4608                                         q_p = &q.itd->itd_next;
4609                                         hw_p = &q.itd->hw_next;
4610                                         type = Q_NEXT_TYPE(fotg210,
4611                                                         q.itd->hw_next);
4612                                         q = *q_p;
4613                                         break;
4614                                 }
4615                         }
4616
4617                         /* Take finished ITDs out of the schedule
4618                          * and process them:  recycle, maybe report
4619                          * URB completion.  HC won't cache the
4620                          * pointer for much longer, if at all.
4621                          */
4622                         *q_p = q.itd->itd_next;
4623                         *hw_p = q.itd->hw_next;
4624                         type = Q_NEXT_TYPE(fotg210, q.itd->hw_next);
4625                         wmb();
4626                         modified = itd_complete(fotg210, q.itd);
4627                         q = *q_p;
4628                         break;
4629                 default:
4630                         fotg210_dbg(fotg210, "corrupt type %d frame %d shadow %p\n",
4631                                         type, frame, q.ptr);
4632                         /* FALL THROUGH */
4633                 case Q_TYPE_QH:
4634                 case Q_TYPE_FSTN:
4635                         /* End of the iTDs and siTDs */
4636                         q.ptr = NULL;
4637                         break;
4638                 }
4639
4640                 /* assume completion callbacks modify the queue */
4641                 if (unlikely(modified && fotg210->isoc_count > 0))
4642                         return -EINVAL;
4643         }
4644         return 0;
4645 }
4646
4647 static void scan_isoc(struct fotg210_hcd *fotg210)
4648 {
4649         unsigned uf, now_frame, frame, ret;
4650         unsigned fmask = fotg210->periodic_size - 1;
4651         bool live;
4652
4653         /*
4654          * When running, scan from last scan point up to "now"
4655          * else clean up by scanning everything that's left.
4656          * Touches as few pages as possible:  cache-friendly.
4657          */
4658         if (fotg210->rh_state >= FOTG210_RH_RUNNING) {
4659                 uf = fotg210_read_frame_index(fotg210);
4660                 now_frame = (uf >> 3) & fmask;
4661                 live = true;
4662         } else  {
4663                 now_frame = (fotg210->next_frame - 1) & fmask;
4664                 live = false;
4665         }
4666         fotg210->now_frame = now_frame;
4667
4668         frame = fotg210->next_frame;
4669         for (;;) {
4670                 ret = 1;
4671                 while (ret != 0)
4672                         ret = scan_frame_queue(fotg210, frame,
4673                                         now_frame, live);
4674
4675                 /* Stop when we have reached the current frame */
4676                 if (frame == now_frame)
4677                         break;
4678                 frame = (frame + 1) & fmask;
4679         }
4680         fotg210->next_frame = now_frame;
4681 }
4682
4683 /* Display / Set uframe_periodic_max
4684  */
4685 static ssize_t uframe_periodic_max_show(struct device *dev,
4686                 struct device_attribute *attr, char *buf)
4687 {
4688         struct fotg210_hcd *fotg210;
4689         int n;
4690
4691         fotg210 = hcd_to_fotg210(bus_to_hcd(dev_get_drvdata(dev)));
4692         n = scnprintf(buf, PAGE_SIZE, "%d\n", fotg210->uframe_periodic_max);
4693         return n;
4694 }
4695
4696
4697 static ssize_t uframe_periodic_max_store(struct device *dev,
4698                 struct device_attribute *attr, const char *buf, size_t count)
4699 {
4700         struct fotg210_hcd *fotg210;
4701         unsigned uframe_periodic_max;
4702         unsigned frame, uframe;
4703         unsigned short allocated_max;
4704         unsigned long flags;
4705         ssize_t ret;
4706
4707         fotg210 = hcd_to_fotg210(bus_to_hcd(dev_get_drvdata(dev)));
4708         if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
4709                 return -EINVAL;
4710
4711         if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
4712                 fotg210_info(fotg210, "rejecting invalid request for uframe_periodic_max=%u\n",
4713                                 uframe_periodic_max);
4714                 return -EINVAL;
4715         }
4716
4717         ret = -EINVAL;
4718
4719         /*
4720          * lock, so that our checking does not race with possible periodic
4721          * bandwidth allocation through submitting new urbs.
4722          */
4723         spin_lock_irqsave(&fotg210->lock, flags);
4724
4725         /*
4726          * for request to decrease max periodic bandwidth, we have to check
4727          * every microframe in the schedule to see whether the decrease is
4728          * possible.
4729          */
4730         if (uframe_periodic_max < fotg210->uframe_periodic_max) {
4731                 allocated_max = 0;
4732
4733                 for (frame = 0; frame < fotg210->periodic_size; ++frame)
4734                         for (uframe = 0; uframe < 7; ++uframe)
4735                                 allocated_max = max(allocated_max,
4736                                                 periodic_usecs(fotg210, frame,
4737                                                 uframe));
4738
4739                 if (allocated_max > uframe_periodic_max) {
4740                         fotg210_info(fotg210,
4741                                         "cannot decrease uframe_periodic_max because periodic bandwidth is already allocated (%u > %u)\n",
4742                                         allocated_max, uframe_periodic_max);
4743                         goto out_unlock;
4744                 }
4745         }
4746
4747         /* increasing is always ok */
4748
4749         fotg210_info(fotg210,
4750                         "setting max periodic bandwidth to %u%% (== %u usec/uframe)\n",
4751                         100 * uframe_periodic_max/125, uframe_periodic_max);
4752
4753         if (uframe_periodic_max != 100)
4754                 fotg210_warn(fotg210, "max periodic bandwidth set is non-standard\n");
4755
4756         fotg210->uframe_periodic_max = uframe_periodic_max;
4757         ret = count;
4758
4759 out_unlock:
4760         spin_unlock_irqrestore(&fotg210->lock, flags);
4761         return ret;
4762 }
4763
4764 static DEVICE_ATTR_RW(uframe_periodic_max);
4765
4766 static inline int create_sysfs_files(struct fotg210_hcd *fotg210)
4767 {
4768         struct device *controller = fotg210_to_hcd(fotg210)->self.controller;
4769
4770         return device_create_file(controller, &dev_attr_uframe_periodic_max);
4771 }
4772
4773 static inline void remove_sysfs_files(struct fotg210_hcd *fotg210)
4774 {
4775         struct device *controller = fotg210_to_hcd(fotg210)->self.controller;
4776
4777         device_remove_file(controller, &dev_attr_uframe_periodic_max);
4778 }
4779 /* On some systems, leaving remote wakeup enabled prevents system shutdown.
4780  * The firmware seems to think that powering off is a wakeup event!
4781  * This routine turns off remote wakeup and everything else, on all ports.
4782  */
4783 static void fotg210_turn_off_all_ports(struct fotg210_hcd *fotg210)
4784 {
4785         u32 __iomem *status_reg = &fotg210->regs->port_status;
4786
4787         fotg210_writel(fotg210, PORT_RWC_BITS, status_reg);
4788 }
4789
4790 /* Halt HC, turn off all ports, and let the BIOS use the companion controllers.
4791  * Must be called with interrupts enabled and the lock not held.
4792  */
4793 static void fotg210_silence_controller(struct fotg210_hcd *fotg210)
4794 {
4795         fotg210_halt(fotg210);
4796
4797         spin_lock_irq(&fotg210->lock);
4798         fotg210->rh_state = FOTG210_RH_HALTED;
4799         fotg210_turn_off_all_ports(fotg210);
4800         spin_unlock_irq(&fotg210->lock);
4801 }
4802
4803 /* fotg210_shutdown kick in for silicon on any bus (not just pci, etc).
4804  * This forcibly disables dma and IRQs, helping kexec and other cases
4805  * where the next system software may expect clean state.
4806  */
4807 static void fotg210_shutdown(struct usb_hcd *hcd)
4808 {
4809         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4810
4811         spin_lock_irq(&fotg210->lock);
4812         fotg210->shutdown = true;
4813         fotg210->rh_state = FOTG210_RH_STOPPING;
4814         fotg210->enabled_hrtimer_events = 0;
4815         spin_unlock_irq(&fotg210->lock);
4816
4817         fotg210_silence_controller(fotg210);
4818
4819         hrtimer_cancel(&fotg210->hrtimer);
4820 }
4821
4822 /* fotg210_work is called from some interrupts, timers, and so on.
4823  * it calls driver completion functions, after dropping fotg210->lock.
4824  */
4825 static void fotg210_work(struct fotg210_hcd *fotg210)
4826 {
4827         /* another CPU may drop fotg210->lock during a schedule scan while
4828          * it reports urb completions.  this flag guards against bogus
4829          * attempts at re-entrant schedule scanning.
4830          */
4831         if (fotg210->scanning) {
4832                 fotg210->need_rescan = true;
4833                 return;
4834         }
4835         fotg210->scanning = true;
4836
4837 rescan:
4838         fotg210->need_rescan = false;
4839         if (fotg210->async_count)
4840                 scan_async(fotg210);
4841         if (fotg210->intr_count > 0)
4842                 scan_intr(fotg210);
4843         if (fotg210->isoc_count > 0)
4844                 scan_isoc(fotg210);
4845         if (fotg210->need_rescan)
4846                 goto rescan;
4847         fotg210->scanning = false;
4848
4849         /* the IO watchdog guards against hardware or driver bugs that
4850          * misplace IRQs, and should let us run completely without IRQs.
4851          * such lossage has been observed on both VT6202 and VT8235.
4852          */
4853         turn_on_io_watchdog(fotg210);
4854 }
4855
4856 /* Called when the fotg210_hcd module is removed.
4857  */
4858 static void fotg210_stop(struct usb_hcd *hcd)
4859 {
4860         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4861
4862         fotg210_dbg(fotg210, "stop\n");
4863
4864         /* no more interrupts ... */
4865
4866         spin_lock_irq(&fotg210->lock);
4867         fotg210->enabled_hrtimer_events = 0;
4868         spin_unlock_irq(&fotg210->lock);
4869
4870         fotg210_quiesce(fotg210);
4871         fotg210_silence_controller(fotg210);
4872         fotg210_reset(fotg210);
4873
4874         hrtimer_cancel(&fotg210->hrtimer);
4875         remove_sysfs_files(fotg210);
4876         remove_debug_files(fotg210);
4877
4878         /* root hub is shut down separately (first, when possible) */
4879         spin_lock_irq(&fotg210->lock);
4880         end_free_itds(fotg210);
4881         spin_unlock_irq(&fotg210->lock);
4882         fotg210_mem_cleanup(fotg210);
4883
4884 #ifdef FOTG210_STATS
4885         fotg210_dbg(fotg210, "irq normal %ld err %ld iaa %ld (lost %ld)\n",
4886                         fotg210->stats.normal, fotg210->stats.error,
4887                         fotg210->stats.iaa, fotg210->stats.lost_iaa);
4888         fotg210_dbg(fotg210, "complete %ld unlink %ld\n",
4889                         fotg210->stats.complete, fotg210->stats.unlink);
4890 #endif
4891
4892         dbg_status(fotg210, "fotg210_stop completed",
4893                         fotg210_readl(fotg210, &fotg210->regs->status));
4894 }
4895
4896 /* one-time init, only for memory state */
4897 static int hcd_fotg210_init(struct usb_hcd *hcd)
4898 {
4899         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4900         u32 temp;
4901         int retval;
4902         u32 hcc_params;
4903         struct fotg210_qh_hw *hw;
4904
4905         spin_lock_init(&fotg210->lock);
4906
4907         /*
4908          * keep io watchdog by default, those good HCDs could turn off it later
4909          */
4910         fotg210->need_io_watchdog = 1;
4911
4912         hrtimer_init(&fotg210->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
4913         fotg210->hrtimer.function = fotg210_hrtimer_func;
4914         fotg210->next_hrtimer_event = FOTG210_HRTIMER_NO_EVENT;
4915
4916         hcc_params = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
4917
4918         /*
4919          * by default set standard 80% (== 100 usec/uframe) max periodic
4920          * bandwidth as required by USB 2.0
4921          */
4922         fotg210->uframe_periodic_max = 100;
4923
4924         /*
4925          * hw default: 1K periodic list heads, one per frame.
4926          * periodic_size can shrink by USBCMD update if hcc_params allows.
4927          */
4928         fotg210->periodic_size = DEFAULT_I_TDPS;
4929         INIT_LIST_HEAD(&fotg210->intr_qh_list);
4930         INIT_LIST_HEAD(&fotg210->cached_itd_list);
4931
4932         if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
4933                 /* periodic schedule size can be smaller than default */
4934                 switch (FOTG210_TUNE_FLS) {
4935                 case 0:
4936                         fotg210->periodic_size = 1024;
4937                         break;
4938                 case 1:
4939                         fotg210->periodic_size = 512;
4940                         break;
4941                 case 2:
4942                         fotg210->periodic_size = 256;
4943                         break;
4944                 default:
4945                         BUG();
4946                 }
4947         }
4948         retval = fotg210_mem_init(fotg210, GFP_KERNEL);
4949         if (retval < 0)
4950                 return retval;
4951
4952         /* controllers may cache some of the periodic schedule ... */
4953         fotg210->i_thresh = 2;
4954
4955         /*
4956          * dedicate a qh for the async ring head, since we couldn't unlink
4957          * a 'real' qh without stopping the async schedule [4.8].  use it
4958          * as the 'reclamation list head' too.
4959          * its dummy is used in hw_alt_next of many tds, to prevent the qh
4960          * from automatically advancing to the next td after short reads.
4961          */
4962         fotg210->async->qh_next.qh = NULL;
4963         hw = fotg210->async->hw;
4964         hw->hw_next = QH_NEXT(fotg210, fotg210->async->qh_dma);
4965         hw->hw_info1 = cpu_to_hc32(fotg210, QH_HEAD);
4966         hw->hw_token = cpu_to_hc32(fotg210, QTD_STS_HALT);
4967         hw->hw_qtd_next = FOTG210_LIST_END(fotg210);
4968         fotg210->async->qh_state = QH_STATE_LINKED;
4969         hw->hw_alt_next = QTD_NEXT(fotg210, fotg210->async->dummy->qtd_dma);
4970
4971         /* clear interrupt enables, set irq latency */
4972         if (log2_irq_thresh < 0 || log2_irq_thresh > 6)
4973                 log2_irq_thresh = 0;
4974         temp = 1 << (16 + log2_irq_thresh);
4975         if (HCC_CANPARK(hcc_params)) {
4976                 /* HW default park == 3, on hardware that supports it (like
4977                  * NVidia and ALI silicon), maximizes throughput on the async
4978                  * schedule by avoiding QH fetches between transfers.
4979                  *
4980                  * With fast usb storage devices and NForce2, "park" seems to
4981                  * make problems:  throughput reduction (!), data errors...
4982                  */
4983                 if (park) {
4984                         park = min_t(unsigned, park, 3);
4985                         temp |= CMD_PARK;
4986                         temp |= park << 8;
4987                 }
4988                 fotg210_dbg(fotg210, "park %d\n", park);
4989         }
4990         if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
4991                 /* periodic schedule size can be smaller than default */
4992                 temp &= ~(3 << 2);
4993                 temp |= (FOTG210_TUNE_FLS << 2);
4994         }
4995         fotg210->command = temp;
4996
4997         /* Accept arbitrarily long scatter-gather lists */
4998         if (!(hcd->driver->flags & HCD_LOCAL_MEM))
4999                 hcd->self.sg_tablesize = ~0;
5000         return 0;
5001 }
5002
5003 /* start HC running; it's halted, hcd_fotg210_init() has been run (once) */
5004 static int fotg210_run(struct usb_hcd *hcd)
5005 {
5006         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5007         u32 temp;
5008         u32 hcc_params;
5009
5010         hcd->uses_new_polling = 1;
5011
5012         /* EHCI spec section 4.1 */
5013
5014         fotg210_writel(fotg210, fotg210->periodic_dma,
5015                         &fotg210->regs->frame_list);
5016         fotg210_writel(fotg210, (u32)fotg210->async->qh_dma,
5017                         &fotg210->regs->async_next);
5018
5019         /*
5020          * hcc_params controls whether fotg210->regs->segment must (!!!)
5021          * be used; it constrains QH/ITD/SITD and QTD locations.
5022          * dma_pool consistent memory always uses segment zero.
5023          * streaming mappings for I/O buffers, like pci_map_single(),
5024          * can return segments above 4GB, if the device allows.
5025          *
5026          * NOTE:  the dma mask is visible through dev->dma_mask, so
5027          * drivers can pass this info along ... like NETIF_F_HIGHDMA,
5028          * Scsi_Host.highmem_io, and so forth.  It's readonly to all
5029          * host side drivers though.
5030          */
5031         hcc_params = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
5032
5033         /*
5034          * Philips, Intel, and maybe others need CMD_RUN before the
5035          * root hub will detect new devices (why?); NEC doesn't
5036          */
5037         fotg210->command &= ~(CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
5038         fotg210->command |= CMD_RUN;
5039         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
5040         dbg_cmd(fotg210, "init", fotg210->command);
5041
5042         /*
5043          * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
5044          * are explicitly handed to companion controller(s), so no TT is
5045          * involved with the root hub.  (Except where one is integrated,
5046          * and there's no companion controller unless maybe for USB OTG.)
5047          *
5048          * Turning on the CF flag will transfer ownership of all ports
5049          * from the companions to the EHCI controller.  If any of the
5050          * companions are in the middle of a port reset at the time, it
5051          * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
5052          * guarantees that no resets are in progress.  After we set CF,
5053          * a short delay lets the hardware catch up; new resets shouldn't
5054          * be started before the port switching actions could complete.
5055          */
5056         down_write(&ehci_cf_port_reset_rwsem);
5057         fotg210->rh_state = FOTG210_RH_RUNNING;
5058         /* unblock posted writes */
5059         fotg210_readl(fotg210, &fotg210->regs->command);
5060         usleep_range(5000, 10000);
5061         up_write(&ehci_cf_port_reset_rwsem);
5062         fotg210->last_periodic_enable = ktime_get_real();
5063
5064         temp = HC_VERSION(fotg210,
5065                         fotg210_readl(fotg210, &fotg210->caps->hc_capbase));
5066         fotg210_info(fotg210,
5067                         "USB %x.%x started, EHCI %x.%02x\n",
5068                         ((fotg210->sbrn & 0xf0) >> 4), (fotg210->sbrn & 0x0f),
5069                         temp >> 8, temp & 0xff);
5070
5071         fotg210_writel(fotg210, INTR_MASK,
5072                         &fotg210->regs->intr_enable); /* Turn On Interrupts */
5073
5074         /* GRR this is run-once init(), being done every time the HC starts.
5075          * So long as they're part of class devices, we can't do it init()
5076          * since the class device isn't created that early.
5077          */
5078         create_debug_files(fotg210);
5079         create_sysfs_files(fotg210);
5080
5081         return 0;
5082 }
5083
5084 static int fotg210_setup(struct usb_hcd *hcd)
5085 {
5086         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5087         int retval;
5088
5089         fotg210->regs = (void __iomem *)fotg210->caps +
5090                         HC_LENGTH(fotg210,
5091                         fotg210_readl(fotg210, &fotg210->caps->hc_capbase));
5092         dbg_hcs_params(fotg210, "reset");
5093         dbg_hcc_params(fotg210, "reset");
5094
5095         /* cache this readonly data; minimize chip reads */
5096         fotg210->hcs_params = fotg210_readl(fotg210,
5097                         &fotg210->caps->hcs_params);
5098
5099         fotg210->sbrn = HCD_USB2;
5100
5101         /* data structure init */
5102         retval = hcd_fotg210_init(hcd);
5103         if (retval)
5104                 return retval;
5105
5106         retval = fotg210_halt(fotg210);
5107         if (retval)
5108                 return retval;
5109
5110         fotg210_reset(fotg210);
5111
5112         return 0;
5113 }
5114
5115 static irqreturn_t fotg210_irq(struct usb_hcd *hcd)
5116 {
5117         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5118         u32 status, masked_status, pcd_status = 0, cmd;
5119         int bh;
5120
5121         spin_lock(&fotg210->lock);
5122
5123         status = fotg210_readl(fotg210, &fotg210->regs->status);
5124
5125         /* e.g. cardbus physical eject */
5126         if (status == ~(u32) 0) {
5127                 fotg210_dbg(fotg210, "device removed\n");
5128                 goto dead;
5129         }
5130
5131         /*
5132          * We don't use STS_FLR, but some controllers don't like it to
5133          * remain on, so mask it out along with the other status bits.
5134          */
5135         masked_status = status & (INTR_MASK | STS_FLR);
5136
5137         /* Shared IRQ? */
5138         if (!masked_status ||
5139                         unlikely(fotg210->rh_state == FOTG210_RH_HALTED)) {
5140                 spin_unlock(&fotg210->lock);
5141                 return IRQ_NONE;
5142         }
5143
5144         /* clear (just) interrupts */
5145         fotg210_writel(fotg210, masked_status, &fotg210->regs->status);
5146         cmd = fotg210_readl(fotg210, &fotg210->regs->command);
5147         bh = 0;
5148
5149         /* unrequested/ignored: Frame List Rollover */
5150         dbg_status(fotg210, "irq", status);
5151
5152         /* INT, ERR, and IAA interrupt rates can be throttled */
5153
5154         /* normal [4.15.1.2] or error [4.15.1.1] completion */
5155         if (likely((status & (STS_INT|STS_ERR)) != 0)) {
5156                 if (likely((status & STS_ERR) == 0))
5157                         COUNT(fotg210->stats.normal);
5158                 else
5159                         COUNT(fotg210->stats.error);
5160                 bh = 1;
5161         }
5162
5163         /* complete the unlinking of some qh [4.15.2.3] */
5164         if (status & STS_IAA) {
5165
5166                 /* Turn off the IAA watchdog */
5167                 fotg210->enabled_hrtimer_events &=
5168                         ~BIT(FOTG210_HRTIMER_IAA_WATCHDOG);
5169
5170                 /*
5171                  * Mild optimization: Allow another IAAD to reset the
5172                  * hrtimer, if one occurs before the next expiration.
5173                  * In theory we could always cancel the hrtimer, but
5174                  * tests show that about half the time it will be reset
5175                  * for some other event anyway.
5176                  */
5177                 if (fotg210->next_hrtimer_event == FOTG210_HRTIMER_IAA_WATCHDOG)
5178                         ++fotg210->next_hrtimer_event;
5179
5180                 /* guard against (alleged) silicon errata */
5181                 if (cmd & CMD_IAAD)
5182                         fotg210_dbg(fotg210, "IAA with IAAD still set?\n");
5183                 if (fotg210->async_iaa) {
5184                         COUNT(fotg210->stats.iaa);
5185                         end_unlink_async(fotg210);
5186                 } else
5187                         fotg210_dbg(fotg210, "IAA with nothing unlinked?\n");
5188         }
5189
5190         /* remote wakeup [4.3.1] */
5191         if (status & STS_PCD) {
5192                 int pstatus;
5193                 u32 __iomem *status_reg = &fotg210->regs->port_status;
5194
5195                 /* kick root hub later */
5196                 pcd_status = status;
5197
5198                 /* resume root hub? */
5199                 if (fotg210->rh_state == FOTG210_RH_SUSPENDED)
5200                         usb_hcd_resume_root_hub(hcd);
5201
5202                 pstatus = fotg210_readl(fotg210, status_reg);
5203
5204                 if (test_bit(0, &fotg210->suspended_ports) &&
5205                                 ((pstatus & PORT_RESUME) ||
5206                                 !(pstatus & PORT_SUSPEND)) &&
5207                                 (pstatus & PORT_PE) &&
5208                                 fotg210->reset_done[0] == 0) {
5209
5210                         /* start 20 msec resume signaling from this port,
5211                          * and make hub_wq collect PORT_STAT_C_SUSPEND to
5212                          * stop that signaling.  Use 5 ms extra for safety,
5213                          * like usb_port_resume() does.
5214                          */
5215                         fotg210->reset_done[0] = jiffies + msecs_to_jiffies(25);
5216                         set_bit(0, &fotg210->resuming_ports);
5217                         fotg210_dbg(fotg210, "port 1 remote wakeup\n");
5218                         mod_timer(&hcd->rh_timer, fotg210->reset_done[0]);
5219                 }
5220         }
5221
5222         /* PCI errors [4.15.2.4] */
5223         if (unlikely((status & STS_FATAL) != 0)) {
5224                 fotg210_err(fotg210, "fatal error\n");
5225                 dbg_cmd(fotg210, "fatal", cmd);
5226                 dbg_status(fotg210, "fatal", status);
5227 dead:
5228                 usb_hc_died(hcd);
5229
5230                 /* Don't let the controller do anything more */
5231                 fotg210->shutdown = true;
5232                 fotg210->rh_state = FOTG210_RH_STOPPING;
5233                 fotg210->command &= ~(CMD_RUN | CMD_ASE | CMD_PSE);
5234                 fotg210_writel(fotg210, fotg210->command,
5235                                 &fotg210->regs->command);
5236                 fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
5237                 fotg210_handle_controller_death(fotg210);
5238
5239                 /* Handle completions when the controller stops */
5240                 bh = 0;
5241         }
5242
5243         if (bh)
5244                 fotg210_work(fotg210);
5245         spin_unlock(&fotg210->lock);
5246         if (pcd_status)
5247                 usb_hcd_poll_rh_status(hcd);
5248         return IRQ_HANDLED;
5249 }
5250
5251 /* non-error returns are a promise to giveback() the urb later
5252  * we drop ownership so next owner (or urb unlink) can get it
5253  *
5254  * urb + dev is in hcd.self.controller.urb_list
5255  * we're queueing TDs onto software and hardware lists
5256  *
5257  * hcd-specific init for hcpriv hasn't been done yet
5258  *
5259  * NOTE:  control, bulk, and interrupt share the same code to append TDs
5260  * to a (possibly active) QH, and the same QH scanning code.
5261  */
5262 static int fotg210_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
5263                 gfp_t mem_flags)
5264 {
5265         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5266         struct list_head qtd_list;
5267
5268         INIT_LIST_HEAD(&qtd_list);
5269
5270         switch (usb_pipetype(urb->pipe)) {
5271         case PIPE_CONTROL:
5272                 /* qh_completions() code doesn't handle all the fault cases
5273                  * in multi-TD control transfers.  Even 1KB is rare anyway.
5274                  */
5275                 if (urb->transfer_buffer_length > (16 * 1024))
5276                         return -EMSGSIZE;
5277                 /* FALLTHROUGH */
5278         /* case PIPE_BULK: */
5279         default:
5280                 if (!qh_urb_transaction(fotg210, urb, &qtd_list, mem_flags))
5281                         return -ENOMEM;
5282                 return submit_async(fotg210, urb, &qtd_list, mem_flags);
5283
5284         case PIPE_INTERRUPT:
5285                 if (!qh_urb_transaction(fotg210, urb, &qtd_list, mem_flags))
5286                         return -ENOMEM;
5287                 return intr_submit(fotg210, urb, &qtd_list, mem_flags);
5288
5289         case PIPE_ISOCHRONOUS:
5290                 return itd_submit(fotg210, urb, mem_flags);
5291         }
5292 }
5293
5294 /* remove from hardware lists
5295  * completions normally happen asynchronously
5296  */
5297
5298 static int fotg210_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
5299 {
5300         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5301         struct fotg210_qh *qh;
5302         unsigned long flags;
5303         int rc;
5304
5305         spin_lock_irqsave(&fotg210->lock, flags);
5306         rc = usb_hcd_check_unlink_urb(hcd, urb, status);
5307         if (rc)
5308                 goto done;
5309
5310         switch (usb_pipetype(urb->pipe)) {
5311         /* case PIPE_CONTROL: */
5312         /* case PIPE_BULK:*/
5313         default:
5314                 qh = (struct fotg210_qh *) urb->hcpriv;
5315                 if (!qh)
5316                         break;
5317                 switch (qh->qh_state) {
5318                 case QH_STATE_LINKED:
5319                 case QH_STATE_COMPLETING:
5320                         start_unlink_async(fotg210, qh);
5321                         break;
5322                 case QH_STATE_UNLINK:
5323                 case QH_STATE_UNLINK_WAIT:
5324                         /* already started */
5325                         break;
5326                 case QH_STATE_IDLE:
5327                         /* QH might be waiting for a Clear-TT-Buffer */
5328                         qh_completions(fotg210, qh);
5329                         break;
5330                 }
5331                 break;
5332
5333         case PIPE_INTERRUPT:
5334                 qh = (struct fotg210_qh *) urb->hcpriv;
5335                 if (!qh)
5336                         break;
5337                 switch (qh->qh_state) {
5338                 case QH_STATE_LINKED:
5339                 case QH_STATE_COMPLETING:
5340                         start_unlink_intr(fotg210, qh);
5341                         break;
5342                 case QH_STATE_IDLE:
5343                         qh_completions(fotg210, qh);
5344                         break;
5345                 default:
5346                         fotg210_dbg(fotg210, "bogus qh %p state %d\n",
5347                                         qh, qh->qh_state);
5348                         goto done;
5349                 }
5350                 break;
5351
5352         case PIPE_ISOCHRONOUS:
5353                 /* itd... */
5354
5355                 /* wait till next completion, do it then. */
5356                 /* completion irqs can wait up to 1024 msec, */
5357                 break;
5358         }
5359 done:
5360         spin_unlock_irqrestore(&fotg210->lock, flags);
5361         return rc;
5362 }
5363
5364 /* bulk qh holds the data toggle */
5365
5366 static void fotg210_endpoint_disable(struct usb_hcd *hcd,
5367                 struct usb_host_endpoint *ep)
5368 {
5369         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5370         unsigned long flags;
5371         struct fotg210_qh *qh, *tmp;
5372
5373         /* ASSERT:  any requests/urbs are being unlinked */
5374         /* ASSERT:  nobody can be submitting urbs for this any more */
5375
5376 rescan:
5377         spin_lock_irqsave(&fotg210->lock, flags);
5378         qh = ep->hcpriv;
5379         if (!qh)
5380                 goto done;
5381
5382         /* endpoints can be iso streams.  for now, we don't
5383          * accelerate iso completions ... so spin a while.
5384          */
5385         if (qh->hw == NULL) {
5386                 struct fotg210_iso_stream *stream = ep->hcpriv;
5387
5388                 if (!list_empty(&stream->td_list))
5389                         goto idle_timeout;
5390
5391                 /* BUG_ON(!list_empty(&stream->free_list)); */
5392                 kfree(stream);
5393                 goto done;
5394         }
5395
5396         if (fotg210->rh_state < FOTG210_RH_RUNNING)
5397                 qh->qh_state = QH_STATE_IDLE;
5398         switch (qh->qh_state) {
5399         case QH_STATE_LINKED:
5400         case QH_STATE_COMPLETING:
5401                 for (tmp = fotg210->async->qh_next.qh;
5402                                 tmp && tmp != qh;
5403                                 tmp = tmp->qh_next.qh)
5404                         continue;
5405                 /* periodic qh self-unlinks on empty, and a COMPLETING qh
5406                  * may already be unlinked.
5407                  */
5408                 if (tmp)
5409                         start_unlink_async(fotg210, qh);
5410                 /* FALL THROUGH */
5411         case QH_STATE_UNLINK:           /* wait for hw to finish? */
5412         case QH_STATE_UNLINK_WAIT:
5413 idle_timeout:
5414                 spin_unlock_irqrestore(&fotg210->lock, flags);
5415                 schedule_timeout_uninterruptible(1);
5416                 goto rescan;
5417         case QH_STATE_IDLE:             /* fully unlinked */
5418                 if (qh->clearing_tt)
5419                         goto idle_timeout;
5420                 if (list_empty(&qh->qtd_list)) {
5421                         qh_destroy(fotg210, qh);
5422                         break;
5423                 }
5424                 /* fall through */
5425         default:
5426                 /* caller was supposed to have unlinked any requests;
5427                  * that's not our job.  just leak this memory.
5428                  */
5429                 fotg210_err(fotg210, "qh %p (#%02x) state %d%s\n",
5430                                 qh, ep->desc.bEndpointAddress, qh->qh_state,
5431                                 list_empty(&qh->qtd_list) ? "" : "(has tds)");
5432                 break;
5433         }
5434 done:
5435         ep->hcpriv = NULL;
5436         spin_unlock_irqrestore(&fotg210->lock, flags);
5437 }
5438
5439 static void fotg210_endpoint_reset(struct usb_hcd *hcd,
5440                 struct usb_host_endpoint *ep)
5441 {
5442         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5443         struct fotg210_qh *qh;
5444         int eptype = usb_endpoint_type(&ep->desc);
5445         int epnum = usb_endpoint_num(&ep->desc);
5446         int is_out = usb_endpoint_dir_out(&ep->desc);
5447         unsigned long flags;
5448
5449         if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
5450                 return;
5451
5452         spin_lock_irqsave(&fotg210->lock, flags);
5453         qh = ep->hcpriv;
5454
5455         /* For Bulk and Interrupt endpoints we maintain the toggle state
5456          * in the hardware; the toggle bits in udev aren't used at all.
5457          * When an endpoint is reset by usb_clear_halt() we must reset
5458          * the toggle bit in the QH.
5459          */
5460         if (qh) {
5461                 usb_settoggle(qh->dev, epnum, is_out, 0);
5462                 if (!list_empty(&qh->qtd_list)) {
5463                         WARN_ONCE(1, "clear_halt for a busy endpoint\n");
5464                 } else if (qh->qh_state == QH_STATE_LINKED ||
5465                                 qh->qh_state == QH_STATE_COMPLETING) {
5466
5467                         /* The toggle value in the QH can't be updated
5468                          * while the QH is active.  Unlink it now;
5469                          * re-linking will call qh_refresh().
5470                          */
5471                         if (eptype == USB_ENDPOINT_XFER_BULK)
5472                                 start_unlink_async(fotg210, qh);
5473                         else
5474                                 start_unlink_intr(fotg210, qh);
5475                 }
5476         }
5477         spin_unlock_irqrestore(&fotg210->lock, flags);
5478 }
5479
5480 static int fotg210_get_frame(struct usb_hcd *hcd)
5481 {
5482         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5483
5484         return (fotg210_read_frame_index(fotg210) >> 3) %
5485                 fotg210->periodic_size;
5486 }
5487
5488 /* The EHCI in ChipIdea HDRC cannot be a separate module or device,
5489  * because its registers (and irq) are shared between host/gadget/otg
5490  * functions  and in order to facilitate role switching we cannot
5491  * give the fotg210 driver exclusive access to those.
5492  */
5493 MODULE_DESCRIPTION(DRIVER_DESC);
5494 MODULE_AUTHOR(DRIVER_AUTHOR);
5495 MODULE_LICENSE("GPL");
5496
5497 static const struct hc_driver fotg210_fotg210_hc_driver = {
5498         .description            = hcd_name,
5499         .product_desc           = "Faraday USB2.0 Host Controller",
5500         .hcd_priv_size          = sizeof(struct fotg210_hcd),
5501
5502         /*
5503          * generic hardware linkage
5504          */
5505         .irq                    = fotg210_irq,
5506         .flags                  = HCD_MEMORY | HCD_USB2,
5507
5508         /*
5509          * basic lifecycle operations
5510          */
5511         .reset                  = hcd_fotg210_init,
5512         .start                  = fotg210_run,
5513         .stop                   = fotg210_stop,
5514         .shutdown               = fotg210_shutdown,
5515
5516         /*
5517          * managing i/o requests and associated device resources
5518          */
5519         .urb_enqueue            = fotg210_urb_enqueue,
5520         .urb_dequeue            = fotg210_urb_dequeue,
5521         .endpoint_disable       = fotg210_endpoint_disable,
5522         .endpoint_reset         = fotg210_endpoint_reset,
5523
5524         /*
5525          * scheduling support
5526          */
5527         .get_frame_number       = fotg210_get_frame,
5528
5529         /*
5530          * root hub support
5531          */
5532         .hub_status_data        = fotg210_hub_status_data,
5533         .hub_control            = fotg210_hub_control,
5534         .bus_suspend            = fotg210_bus_suspend,
5535         .bus_resume             = fotg210_bus_resume,
5536
5537         .relinquish_port        = fotg210_relinquish_port,
5538         .port_handed_over       = fotg210_port_handed_over,
5539
5540         .clear_tt_buffer_complete = fotg210_clear_tt_buffer_complete,
5541 };
5542
5543 static void fotg210_init(struct fotg210_hcd *fotg210)
5544 {
5545         u32 value;
5546
5547         iowrite32(GMIR_MDEV_INT | GMIR_MOTG_INT | GMIR_INT_POLARITY,
5548                         &fotg210->regs->gmir);
5549
5550         value = ioread32(&fotg210->regs->otgcsr);
5551         value &= ~OTGCSR_A_BUS_DROP;
5552         value |= OTGCSR_A_BUS_REQ;
5553         iowrite32(value, &fotg210->regs->otgcsr);
5554 }
5555
5556 /**
5557  * fotg210_hcd_probe - initialize faraday FOTG210 HCDs
5558  *
5559  * Allocates basic resources for this USB host controller, and
5560  * then invokes the start() method for the HCD associated with it
5561  * through the hotplug entry's driver_data.
5562  */
5563 static int fotg210_hcd_probe(struct platform_device *pdev)
5564 {
5565         struct device *dev = &pdev->dev;
5566         struct usb_hcd *hcd;
5567         struct resource *res;
5568         int irq;
5569         int retval;
5570         struct fotg210_hcd *fotg210;
5571
5572         if (usb_disabled())
5573                 return -ENODEV;
5574
5575         pdev->dev.power.power_state = PMSG_ON;
5576
5577         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
5578         if (!res) {
5579                 dev_err(dev, "Found HC with no IRQ. Check %s setup!\n",
5580                                 dev_name(dev));
5581                 return -ENODEV;
5582         }
5583
5584         irq = res->start;
5585
5586         hcd = usb_create_hcd(&fotg210_fotg210_hc_driver, dev,
5587                         dev_name(dev));
5588         if (!hcd) {
5589                 dev_err(dev, "failed to create hcd\n");
5590                 retval = -ENOMEM;
5591                 goto fail_create_hcd;
5592         }
5593
5594         hcd->has_tt = 1;
5595
5596         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
5597         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
5598         if (IS_ERR(hcd->regs)) {
5599                 retval = PTR_ERR(hcd->regs);
5600                 goto failed;
5601         }
5602
5603         hcd->rsrc_start = res->start;
5604         hcd->rsrc_len = resource_size(res);
5605
5606         fotg210 = hcd_to_fotg210(hcd);
5607
5608         fotg210->caps = hcd->regs;
5609
5610         retval = fotg210_setup(hcd);
5611         if (retval)
5612                 goto failed;
5613
5614         fotg210_init(fotg210);
5615
5616         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
5617         if (retval) {
5618                 dev_err(dev, "failed to add hcd with err %d\n", retval);
5619                 goto failed;
5620         }
5621         device_wakeup_enable(hcd->self.controller);
5622
5623         return retval;
5624
5625 failed:
5626         usb_put_hcd(hcd);
5627 fail_create_hcd:
5628         dev_err(dev, "init %s fail, %d\n", dev_name(dev), retval);
5629         return retval;
5630 }
5631
5632 /**
5633  * fotg210_hcd_remove - shutdown processing for EHCI HCDs
5634  * @dev: USB Host Controller being removed
5635  *
5636  */
5637 static int fotg210_hcd_remove(struct platform_device *pdev)
5638 {
5639         struct device *dev = &pdev->dev;
5640         struct usb_hcd *hcd = dev_get_drvdata(dev);
5641
5642         if (!hcd)
5643                 return 0;
5644
5645         usb_remove_hcd(hcd);
5646         usb_put_hcd(hcd);
5647
5648         return 0;
5649 }
5650
5651 static struct platform_driver fotg210_hcd_driver = {
5652         .driver = {
5653                 .name   = "fotg210-hcd",
5654         },
5655         .probe  = fotg210_hcd_probe,
5656         .remove = fotg210_hcd_remove,
5657 };
5658
5659 static int __init fotg210_hcd_init(void)
5660 {
5661         int retval = 0;
5662
5663         if (usb_disabled())
5664                 return -ENODEV;
5665
5666         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
5667         set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5668         if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
5669                         test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
5670                 pr_warn("Warning! fotg210_hcd should always be loaded before uhci_hcd and ohci_hcd, not after\n");
5671
5672         pr_debug("%s: block sizes: qh %zd qtd %zd itd %zd\n",
5673                         hcd_name, sizeof(struct fotg210_qh),
5674                         sizeof(struct fotg210_qtd),
5675                         sizeof(struct fotg210_itd));
5676
5677         fotg210_debug_root = debugfs_create_dir("fotg210", usb_debug_root);
5678
5679         retval = platform_driver_register(&fotg210_hcd_driver);
5680         if (retval < 0)
5681                 goto clean;
5682         return retval;
5683
5684 clean:
5685         debugfs_remove(fotg210_debug_root);
5686         fotg210_debug_root = NULL;
5687
5688         clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5689         return retval;
5690 }
5691 module_init(fotg210_hcd_init);
5692
5693 static void __exit fotg210_hcd_cleanup(void)
5694 {
5695         platform_driver_unregister(&fotg210_hcd_driver);
5696         debugfs_remove(fotg210_debug_root);
5697         clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5698 }
5699 module_exit(fotg210_hcd_cleanup);