drivers/usb/class/usblp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * usblp.c
   4  *
   5  * Copyright (c) 1999 Michael Gee       <michael@linuxspecific.com>
   6  * Copyright (c) 1999 Pavel Machek      <pavel@ucw.cz>
   7  * Copyright (c) 2000 Randy Dunlap      <rdunlap@xenotime.net>
   8  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
   9  # Copyright (c) 2001 Pete Zaitcev      <zaitcev@redhat.com>
  10  # Copyright (c) 2001 David Paschal     <paschal@rcsis.com>
  11  * Copyright (c) 2006 Oliver Neukum     <oliver@neukum.name>
  12  *
  13  * USB Printer Device Class driver for USB printers and printer cables
  14  *
  15  * Sponsored by SuSE
  16  *
  17  * ChangeLog:
  18  *      v0.1 - thorough cleaning, URBification, almost a rewrite
  19  *      v0.2 - some more cleanups
  20  *      v0.3 - cleaner again, waitqueue fixes
  21  *      v0.4 - fixes in unidirectional mode
  22  *      v0.5 - add DEVICE_ID string support
  23  *      v0.6 - never time out
  24  *      v0.7 - fixed bulk-IN read and poll (David Paschal)
  25  *      v0.8 - add devfs support
  26  *      v0.9 - fix unplug-while-open paths
  27  *      v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  28  *      v0.11 - add proto_bias option (Pete Zaitcev)
  29  *      v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  30  *      v0.13 - alloc space for statusbuf (<status> not on stack);
  31  *              use usb_alloc_coherent() for read buf & write buf;
  32  *      none  - Maintained in Linux kernel after v0.13
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/kernel.h>
  37 #include <linux/sched/signal.h>
  38 #include <linux/signal.h>
  39 #include <linux/poll.h>
  40 #include <linux/slab.h>
  41 #include <linux/lp.h>
  42 #include <linux/mutex.h>
  43 #undef DEBUG
  44 #include <linux/usb.h>
  45 #include <linux/usb/ch9.h>
  46 #include <linux/ratelimit.h>
  47
  48 /*
  49  * Version Information
  50  */
  51 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  52 #define DRIVER_DESC "USB Printer Device Class driver"
  53
  54 #define USBLP_BUF_SIZE          8192
  55 #define USBLP_BUF_SIZE_IN       1024
  56 #define USBLP_DEVICE_ID_SIZE    1024
  57
  58 /* ioctls: */
  59 #define IOCNR_GET_DEVICE_ID             1
  60 #define IOCNR_GET_PROTOCOLS             2
  61 #define IOCNR_SET_PROTOCOL              3
  62 #define IOCNR_HP_SET_CHANNEL            4
  63 #define IOCNR_GET_BUS_ADDRESS           5
  64 #define IOCNR_GET_VID_PID               6
  65 #define IOCNR_SOFT_RESET                7
  66 /* Get device_id string: */
  67 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  68 /* The following ioctls were added for http://hpoj.sourceforge.net:
  69  * Get two-int array:
  70  * [0]=current protocol
  71  *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  72  *         3=USB_CLASS_PRINTER/1/3),
  73  * [1]=supported protocol mask (mask&(1<<n)!=0 means
  74  *     USB_CLASS_PRINTER/1/n supported):
  75  */
  76 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  77 /*
  78  * Set protocol
  79  *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  80  *         3=USB_CLASS_PRINTER/1/3):
  81  */
  82 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  83 /* Set channel number (HP Vendor-specific command): */
  84 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  85 /* Get two-int array: [0]=bus number, [1]=device address: */
  86 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  87 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
  88 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  89 /* Perform class specific soft reset */
  90 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  91
  92 /*
  93  * A DEVICE_ID string may include the printer's serial number.
  94  * It should end with a semi-colon (';').
  95  * An example from an HP 970C DeskJet printer is (this is one long string,
  96  * with the serial number changed):
  97 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
  98  */
  99
 100 /*
 101  * USB Printer Requests
 102  */
 103
 104 #define USBLP_REQ_GET_ID                        0x00
 105 #define USBLP_REQ_GET_STATUS                    0x01
 106 #define USBLP_REQ_RESET                         0x02
 107 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 108
 109 #define USBLP_MINORS            16
 110 #define USBLP_MINOR_BASE        0
 111
 112 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 113
 114 #define USBLP_FIRST_PROTOCOL    1
 115 #define USBLP_LAST_PROTOCOL     3
 116 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 117
 118 /*
 119  * some arbitrary status buffer size;
 120  * need a status buffer that is allocated via kmalloc(), not on stack
 121  */
 122 #define STATUS_BUF_SIZE         8
 123
 124 /*
 125  * Locks down the locking order:
 126  * ->wmut locks wstatus.
 127  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 128  * [rw]status. We only touch status when we know the side idle.
 129  * ->lock locks what interrupt accesses.
 130  */
 131 struct usblp {
 132         struct usb_device       *dev;                   /* USB device */
 133         struct mutex            wmut;
 134         struct mutex            mut;
 135         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 136         char                    *readbuf;               /* read transfer_buffer */
 137         char                    *statusbuf;             /* status transfer_buffer */
 138         struct usb_anchor       urbs;
 139         wait_queue_head_t       rwait, wwait;
 140         int                     readcount;              /* Counter for reads */
 141         int                     ifnum;                  /* Interface number */
 142         struct usb_interface    *intf;                  /* The interface */
 143         /*
 144          * Alternate-setting numbers and endpoints for each protocol
 145          * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 146          */
 147         struct {
 148                 int                             alt_setting;
 149                 struct usb_endpoint_descriptor  *epwrite;
 150                 struct usb_endpoint_descriptor  *epread;
 151         }                       protocol[USBLP_MAX_PROTOCOLS];
 152         int                     current_protocol;
 153         int                     minor;                  /* minor number of device */
 154         int                     wcomplete, rcomplete;
 155         int                     wstatus;        /* bytes written or error */
 156         int                     rstatus;        /* bytes ready or error */
 157         unsigned int            quirks;                 /* quirks flags */
 158         unsigned int            flags;                  /* mode flags */
 159         unsigned char           used;                   /* True if open */
 160         unsigned char           present;                /* True if not disconnected */
 161         unsigned char           bidir;                  /* interface is bidirectional */
 162         unsigned char           no_paper;               /* Paper Out happened */
 163         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 164                                                         /* first 2 bytes are (big-endian) length */
 165 };
 166
 167 #ifdef DEBUG
 168 static void usblp_dump(struct usblp *usblp)
 169 {
 170         struct device *dev = &usblp->intf->dev;
 171         int p;
 172
 173         dev_dbg(dev, "usblp=0x%p\n", usblp);
 174         dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 175         dev_dbg(dev, "present=%d\n", usblp->present);
 176         dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 177         dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 178         dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 179         for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 180                 dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 181                         usblp->protocol[p].alt_setting);
 182                 dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 183                         usblp->protocol[p].epwrite);
 184                 dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 185                         usblp->protocol[p].epread);
 186         }
 187         dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 188         dev_dbg(dev, "minor=%d\n", usblp->minor);
 189         dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 190         dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 191         dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 192         dev_dbg(dev, "used=%d\n", usblp->used);
 193         dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 194         dev_dbg(dev, "device_id_string=\"%s\"\n",
 195                 usblp->device_id_string ?
 196                         usblp->device_id_string + 2 :
 197                         (unsigned char *)"(null)");
 198 }
 199 #endif
 200
 201 /* Quirks: various printer quirks are handled by this table & its flags. */
 202
 203 struct quirk_printer_struct {
 204         __u16 vendorId;
 205         __u16 productId;
 206         unsigned int quirks;
 207 };
 208
 209 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 210 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 211 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 212
 213 static const struct quirk_printer_struct quirk_printers[] = {
 214         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 215         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 216         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 217         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 218         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 219         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 220         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 221         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 222         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 223         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 224         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 225         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 226         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 227         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 228         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 229         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 230         { 0, 0 }
 231 };
 232
 233 static int usblp_wwait(struct usblp *usblp, int nonblock);
 234 static int usblp_wtest(struct usblp *usblp, int nonblock);
 235 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 236 static int usblp_rtest(struct usblp *usblp, int nonblock);
 237 static int usblp_submit_read(struct usblp *usblp);
 238 static int usblp_select_alts(struct usblp *usblp);
 239 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 240 static int usblp_cache_device_id_string(struct usblp *usblp);
 241
 242 /* forward reference to make our lives easier */
 243 static struct usb_driver usblp_driver;
 244 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 245
 246 /*
 247  * Functions for usblp control messages.
 248  */
 249
 250 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 251 {
 252         int retval;
 253         int index = usblp->ifnum;
 254
 255         /* High byte has the interface index.
 256            Low byte has the alternate setting.
 257          */
 258         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 259                 index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 260
 261         retval = usb_control_msg(usblp->dev,
 262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 263                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 264         dev_dbg(&usblp->intf->dev,
 265                 "usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
 266                 request, !!dir, recip, value, index, len, retval);
 267         return retval < 0 ? retval : 0;
 268 }
 269
 270 #define usblp_read_status(usblp, status)\
 271         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 272 #define usblp_get_id(usblp, config, id, maxlen)\
 273         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 274 #define usblp_reset(usblp)\
 275         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 276
 277 static int usblp_hp_channel_change_request(struct usblp *usblp, int channel, u8 *new_channel)
 278 {
 279         u8 *buf;
 280         int ret;
 281
 282         buf = kzalloc(1, GFP_KERNEL);
 283         if (!buf)
 284                 return -ENOMEM;
 285
 286         ret = usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST,
 287                         USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE,
 288                         channel, buf, 1);
 289         if (ret == 0)
 290                 *new_channel = buf[0];
 291
 292         kfree(buf);
 293
 294         return ret;
 295 }
 296
 297 /*
 298  * See the description for usblp_select_alts() below for the usage
 299  * explanation.  Look into your /sys/kernel/debug/usb/devices and dmesg in
 300  * case of any trouble.
 301  */
 302 static int proto_bias = -1;
 303
 304 /*
 305  * URB callback.
 306  */
 307
 308 static void usblp_bulk_read(struct urb *urb)
 309 {
 310         struct usblp *usblp = urb->context;
 311         int status = urb->status;
 312         unsigned long flags;
 313
 314         if (usblp->present && usblp->used) {
 315                 if (status)
 316                         printk(KERN_WARNING "usblp%d: "
 317                             "nonzero read bulk status received: %d\n",
 318                             usblp->minor, status);
 319         }
 320         spin_lock_irqsave(&usblp->lock, flags);
 321         if (status < 0)
 322                 usblp->rstatus = status;
 323         else
 324                 usblp->rstatus = urb->actual_length;
 325         usblp->rcomplete = 1;
 326         wake_up(&usblp->rwait);
 327         spin_unlock_irqrestore(&usblp->lock, flags);
 328
 329         usb_free_urb(urb);
 330 }
 331
 332 static void usblp_bulk_write(struct urb *urb)
 333 {
 334         struct usblp *usblp = urb->context;
 335         int status = urb->status;
 336         unsigned long flags;
 337
 338         if (usblp->present && usblp->used) {
 339                 if (status)
 340                         printk(KERN_WARNING "usblp%d: "
 341                             "nonzero write bulk status received: %d\n",
 342                             usblp->minor, status);
 343         }
 344         spin_lock_irqsave(&usblp->lock, flags);
 345         if (status < 0)
 346                 usblp->wstatus = status;
 347         else
 348                 usblp->wstatus = urb->actual_length;
 349         usblp->no_paper = 0;
 350         usblp->wcomplete = 1;
 351         wake_up(&usblp->wwait);
 352         spin_unlock_irqrestore(&usblp->lock, flags);
 353
 354         usb_free_urb(urb);
 355 }
 356
 357 /*
 358  * Get and print printer errors.
 359  */
 360
 361 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 362
 363 static int usblp_check_status(struct usblp *usblp, int err)
 364 {
 365         unsigned char status, newerr = 0;
 366         int error;
 367
 368         mutex_lock(&usblp->mut);
 369         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 370                 mutex_unlock(&usblp->mut);
 371                 printk_ratelimited(KERN_ERR
 372                                 "usblp%d: error %d reading printer status\n",
 373                                 usblp->minor, error);
 374                 return 0;
 375         }
 376         status = *usblp->statusbuf;
 377         mutex_unlock(&usblp->mut);
 378
 379         if (~status & LP_PERRORP)
 380                 newerr = 3;
 381         if (status & LP_POUTPA)
 382                 newerr = 1;
 383         if (~status & LP_PSELECD)
 384                 newerr = 2;
 385
 386         if (newerr != err) {
 387                 printk(KERN_INFO "usblp%d: %s\n",
 388                    usblp->minor, usblp_messages[newerr]);
 389         }
 390
 391         return newerr;
 392 }
 393
 394 static int handle_bidir(struct usblp *usblp)
 395 {
 396         if (usblp->bidir && usblp->used) {
 397                 if (usblp_submit_read(usblp) < 0)
 398                         return -EIO;
 399         }
 400         return 0;
 401 }
 402
 403 /*
 404  * File op functions.
 405  */
 406
 407 static int usblp_open(struct inode *inode, struct file *file)
 408 {
 409         int minor = iminor(inode);
 410         struct usblp *usblp;
 411         struct usb_interface *intf;
 412         int retval;
 413
 414         if (minor < 0)
 415                 return -ENODEV;
 416
 417         mutex_lock(&usblp_mutex);
 418
 419         retval = -ENODEV;
 420         intf = usb_find_interface(&usblp_driver, minor);
 421         if (!intf)
 422                 goto out;
 423         usblp = usb_get_intfdata(intf);
 424         if (!usblp || !usblp->dev || !usblp->present)
 425                 goto out;
 426
 427         retval = -EBUSY;
 428         if (usblp->used)
 429                 goto out;
 430
 431         /*
 432          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 433          *  - We do not want persistent state which close(2) does not clear
 434          *  - It is not used anyway, according to CUPS people
 435          */
 436
 437         retval = usb_autopm_get_interface(intf);
 438         if (retval < 0)
 439                 goto out;
 440         usblp->used = 1;
 441         file->private_data = usblp;
 442
 443         usblp->wcomplete = 1; /* we begin writeable */
 444         usblp->wstatus = 0;
 445         usblp->rcomplete = 0;
 446
 447         if (handle_bidir(usblp) < 0) {
 448                 usb_autopm_put_interface(intf);
 449                 usblp->used = 0;
 450                 file->private_data = NULL;
 451                 retval = -EIO;
 452         }
 453 out:
 454         mutex_unlock(&usblp_mutex);
 455         return retval;
 456 }
 457
 458 static void usblp_cleanup(struct usblp *usblp)
 459 {
 460         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 461
 462         kfree(usblp->readbuf);
 463         kfree(usblp->device_id_string);
 464         kfree(usblp->statusbuf);
 465         usb_put_intf(usblp->intf);
 466         kfree(usblp);
 467 }
 468
 469 static void usblp_unlink_urbs(struct usblp *usblp)
 470 {
 471         usb_kill_anchored_urbs(&usblp->urbs);
 472 }
 473
 474 static int usblp_release(struct inode *inode, struct file *file)
 475 {
 476         struct usblp *usblp = file->private_data;
 477
 478         usblp->flags &= ~LP_ABORT;
 479
 480         mutex_lock(&usblp_mutex);
 481         usblp->used = 0;
 482         if (usblp->present)
 483                 usblp_unlink_urbs(usblp);
 484
 485         usb_autopm_put_interface(usblp->intf);
 486
 487         if (!usblp->present)            /* finish cleanup from disconnect */
 488                 usblp_cleanup(usblp);   /* any URBs must be dead */
 489
 490         mutex_unlock(&usblp_mutex);
 491         return 0;
 492 }
 493
 494 /* No kernel lock - fine */
 495 static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
 496 {
 497         struct usblp *usblp = file->private_data;
 498         __poll_t ret = 0;
 499         unsigned long flags;
 500
 501         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 502         poll_wait(file, &usblp->rwait, wait);
 503         poll_wait(file, &usblp->wwait, wait);
 504
 505         mutex_lock(&usblp->mut);
 506         if (!usblp->present)
 507                 ret |= EPOLLHUP;
 508         mutex_unlock(&usblp->mut);
 509
 510         spin_lock_irqsave(&usblp->lock, flags);
 511         if (usblp->bidir && usblp->rcomplete)
 512                 ret |= EPOLLIN  | EPOLLRDNORM;
 513         if (usblp->no_paper || usblp->wcomplete)
 514                 ret |= EPOLLOUT | EPOLLWRNORM;
 515         spin_unlock_irqrestore(&usblp->lock, flags);
 516         return ret;
 517 }
 518
 519 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 520 {
 521         struct usblp *usblp = file->private_data;
 522         int length, err, i;
 523         unsigned char newChannel;
 524         int status;
 525         int twoints[2];
 526         int retval = 0;
 527
 528         mutex_lock(&usblp->mut);
 529         if (!usblp->present) {
 530                 retval = -ENODEV;
 531                 goto done;
 532         }
 533
 534         dev_dbg(&usblp->intf->dev,
 535                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 536                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 537
 538         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 539
 540                 switch (_IOC_NR(cmd)) {
 541
 542                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 543                         if (_IOC_DIR(cmd) != _IOC_READ) {
 544                                 retval = -EINVAL;
 545                                 goto done;
 546                         }
 547
 548                         length = usblp_cache_device_id_string(usblp);
 549                         if (length < 0) {
 550                                 retval = length;
 551                                 goto done;
 552                         }
 553                         if (length > _IOC_SIZE(cmd))
 554                                 length = _IOC_SIZE(cmd); /* truncate */
 555
 556                         if (copy_to_user((void __user *) arg,
 557                                         usblp->device_id_string,
 558                                         (unsigned long) length)) {
 559                                 retval = -EFAULT;
 560                                 goto done;
 561                         }
 562
 563                         break;
 564
 565                 case IOCNR_GET_PROTOCOLS:
 566                         if (_IOC_DIR(cmd) != _IOC_READ ||
 567                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 568                                 retval = -EINVAL;
 569                                 goto done;
 570                         }
 571
 572                         twoints[0] = usblp->current_protocol;
 573                         twoints[1] = 0;
 574                         for (i = USBLP_FIRST_PROTOCOL;
 575                              i <= USBLP_LAST_PROTOCOL; i++) {
 576                                 if (usblp->protocol[i].alt_setting >= 0)
 577                                         twoints[1] |= (1<<i);
 578                         }
 579
 580                         if (copy_to_user((void __user *)arg,
 581                                         (unsigned char *)twoints,
 582                                         sizeof(twoints))) {
 583                                 retval = -EFAULT;
 584                                 goto done;
 585                         }
 586
 587                         break;
 588
 589                 case IOCNR_SET_PROTOCOL:
 590                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 591                                 retval = -EINVAL;
 592                                 goto done;
 593                         }
 594
 595 #ifdef DEBUG
 596                         if (arg == -10) {
 597                                 usblp_dump(usblp);
 598                                 break;
 599                         }
 600 #endif
 601
 602                         usblp_unlink_urbs(usblp);
 603                         retval = usblp_set_protocol(usblp, arg);
 604                         if (retval < 0) {
 605                                 usblp_set_protocol(usblp,
 606                                         usblp->current_protocol);
 607                         }
 608                         break;
 609
 610                 case IOCNR_HP_SET_CHANNEL:
 611                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 612                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 613                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 614                                 retval = -EINVAL;
 615                                 goto done;
 616                         }
 617
 618                         err = usblp_hp_channel_change_request(usblp,
 619                                 arg, &newChannel);
 620                         if (err < 0) {
 621                                 dev_err(&usblp->dev->dev,
 622                                         "usblp%d: error = %d setting "
 623                                         "HP channel\n",
 624                                         usblp->minor, err);
 625                                 retval = -EIO;
 626                                 goto done;
 627                         }
 628
 629                         dev_dbg(&usblp->intf->dev,
 630                                 "usblp%d requested/got HP channel %ld/%d\n",
 631                                 usblp->minor, arg, newChannel);
 632                         break;
 633
 634                 case IOCNR_GET_BUS_ADDRESS:
 635                         if (_IOC_DIR(cmd) != _IOC_READ ||
 636                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 637                                 retval = -EINVAL;
 638                                 goto done;
 639                         }
 640
 641                         twoints[0] = usblp->dev->bus->busnum;
 642                         twoints[1] = usblp->dev->devnum;
 643                         if (copy_to_user((void __user *)arg,
 644                                         (unsigned char *)twoints,
 645                                         sizeof(twoints))) {
 646                                 retval = -EFAULT;
 647                                 goto done;
 648                         }
 649
 650                         dev_dbg(&usblp->intf->dev,
 651                                 "usblp%d is bus=%d, device=%d\n",
 652                                 usblp->minor, twoints[0], twoints[1]);
 653                         break;
 654
 655                 case IOCNR_GET_VID_PID:
 656                         if (_IOC_DIR(cmd) != _IOC_READ ||
 657                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 658                                 retval = -EINVAL;
 659                                 goto done;
 660                         }
 661
 662                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 663                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 664                         if (copy_to_user((void __user *)arg,
 665                                         (unsigned char *)twoints,
 666                                         sizeof(twoints))) {
 667                                 retval = -EFAULT;
 668                                 goto done;
 669                         }
 670
 671                         dev_dbg(&usblp->intf->dev,
 672                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 673                                 usblp->minor, twoints[0], twoints[1]);
 674                         break;
 675
 676                 case IOCNR_SOFT_RESET:
 677                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 678                                 retval = -EINVAL;
 679                                 goto done;
 680                         }
 681                         retval = usblp_reset(usblp);
 682                         break;
 683                 default:
 684                         retval = -ENOTTY;
 685                 }
 686         else    /* old-style ioctl value */
 687                 switch (cmd) {
 688
 689                 case LPGETSTATUS:
 690                         retval = usblp_read_status(usblp, usblp->statusbuf);
 691                         if (retval) {
 692                                 printk_ratelimited(KERN_ERR "usblp%d:"
 693                                             "failed reading printer status (%d)\n",
 694                                             usblp->minor, retval);
 695                                 retval = -EIO;
 696                                 goto done;
 697                         }
 698                         status = *usblp->statusbuf;
 699                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 700                                 retval = -EFAULT;
 701                         break;
 702
 703                 case LPABORT:
 704                         if (arg)
 705                                 usblp->flags |= LP_ABORT;
 706                         else
 707                                 usblp->flags &= ~LP_ABORT;
 708                         break;
 709
 710                 default:
 711                         retval = -ENOTTY;
 712                 }
 713
 714 done:
 715         mutex_unlock(&usblp->mut);
 716         return retval;
 717 }
 718
 719 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 720 {
 721         struct urb *urb;
 722         char *writebuf;
 723
 724         writebuf = kmalloc(transfer_length, GFP_KERNEL);
 725         if (writebuf == NULL)
 726                 return NULL;
 727         urb = usb_alloc_urb(0, GFP_KERNEL);
 728         if (urb == NULL) {
 729                 kfree(writebuf);
 730                 return NULL;
 731         }
 732
 733         usb_fill_bulk_urb(urb, usblp->dev,
 734                 usb_sndbulkpipe(usblp->dev,
 735                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 736                 writebuf, transfer_length, usblp_bulk_write, usblp);
 737         urb->transfer_flags |= URB_FREE_BUFFER;
 738
 739         return urb;
 740 }
 741
 742 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 743 {
 744         struct usblp *usblp = file->private_data;
 745         struct urb *writeurb;
 746         int rv;
 747         int transfer_length;
 748         ssize_t writecount = 0;
 749
 750         if (mutex_lock_interruptible(&usblp->wmut)) {
 751                 rv = -EINTR;
 752                 goto raise_biglock;
 753         }
 754         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 755                 goto raise_wait;
 756
 757         while (writecount < count) {
 758                 /*
 759                  * Step 1: Submit next block.
 760                  */
 761                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 762                         transfer_length = USBLP_BUF_SIZE;
 763
 764                 rv = -ENOMEM;
 765                 writeurb = usblp_new_writeurb(usblp, transfer_length);
 766                 if (writeurb == NULL)
 767                         goto raise_urb;
 768                 usb_anchor_urb(writeurb, &usblp->urbs);
 769
 770                 if (copy_from_user(writeurb->transfer_buffer,
 771                                    buffer + writecount, transfer_length)) {
 772                         rv = -EFAULT;
 773                         goto raise_badaddr;
 774                 }
 775
 776                 spin_lock_irq(&usblp->lock);
 777                 usblp->wcomplete = 0;
 778                 spin_unlock_irq(&usblp->lock);
 779                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 780                         usblp->wstatus = 0;
 781                         spin_lock_irq(&usblp->lock);
 782                         usblp->no_paper = 0;
 783                         usblp->wcomplete = 1;
 784                         wake_up(&usblp->wwait);
 785                         spin_unlock_irq(&usblp->lock);
 786                         if (rv != -ENOMEM)
 787                                 rv = -EIO;
 788                         goto raise_submit;
 789                 }
 790
 791                 /*
 792                  * Step 2: Wait for transfer to end, collect results.
 793                  */
 794                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 795                 if (rv < 0) {
 796                         if (rv == -EAGAIN) {
 797                                 /* Presume that it's going to complete well. */
 798                                 writecount += transfer_length;
 799                         }
 800                         if (rv == -ENOSPC) {
 801                                 spin_lock_irq(&usblp->lock);
 802                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 803                                 spin_unlock_irq(&usblp->lock);
 804                                 writecount += transfer_length;
 805                         }
 806                         /* Leave URB dangling, to be cleaned on close. */
 807                         goto collect_error;
 808                 }
 809
 810                 if (usblp->wstatus < 0) {
 811                         rv = -EIO;
 812                         goto collect_error;
 813                 }
 814                 /*
 815                  * This is critical: it must be our URB, not other writer's.
 816                  * The wmut exists mainly to cover us here.
 817                  */
 818                 writecount += usblp->wstatus;
 819         }
 820
 821         mutex_unlock(&usblp->wmut);
 822         return writecount;
 823
 824 raise_submit:
 825 raise_badaddr:
 826         usb_unanchor_urb(writeurb);
 827         usb_free_urb(writeurb);
 828 raise_urb:
 829 raise_wait:
 830 collect_error:          /* Out of raise sequence */
 831         mutex_unlock(&usblp->wmut);
 832 raise_biglock:
 833         return writecount ? writecount : rv;
 834 }
 835
 836 /*
 837  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 838  * error, etc. This is the historical behaviour. In all such cases we return
 839  * EIO, and applications loop in order to get the new read going.
 840  */
 841 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 842 {
 843         struct usblp *usblp = file->private_data;
 844         ssize_t count;
 845         ssize_t avail;
 846         int rv;
 847
 848         if (!usblp->bidir)
 849                 return -EINVAL;
 850
 851         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 852         if (rv < 0)
 853                 return rv;
 854
 855         if (!usblp->present) {
 856                 count = -ENODEV;
 857                 goto done;
 858         }
 859
 860         if ((avail = usblp->rstatus) < 0) {
 861                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 862                     usblp->minor, (int)avail);
 863                 usblp_submit_read(usblp);
 864                 count = -EIO;
 865                 goto done;
 866         }
 867
 868         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 869         if (count != 0 &&
 870             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 871                 count = -EFAULT;
 872                 goto done;
 873         }
 874
 875         if ((usblp->readcount += count) == avail) {
 876                 if (usblp_submit_read(usblp) < 0) {
 877                         /* We don't want to leak USB return codes into errno. */
 878                         if (count == 0)
 879                                 count = -EIO;
 880                         goto done;
 881                 }
 882         }
 883
 884 done:
 885         mutex_unlock(&usblp->mut);
 886         return count;
 887 }
 888
 889 /*
 890  * Wait for the write path to come idle.
 891  * This is called under the ->wmut, so the idle path stays idle.
 892  *
 893  * Our write path has a peculiar property: it does not buffer like a tty,
 894  * but waits for the write to succeed. This allows our ->release to bug out
 895  * without waiting for writes to drain. But it obviously does not work
 896  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 897  * select(2) or poll(2) to wait for the buffer to drain before closing.
 898  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 899  */
 900 static int usblp_wwait(struct usblp *usblp, int nonblock)
 901 {
 902         DECLARE_WAITQUEUE(waita, current);
 903         int rc;
 904         int err = 0;
 905
 906         add_wait_queue(&usblp->wwait, &waita);
 907         for (;;) {
 908                 if (mutex_lock_interruptible(&usblp->mut)) {
 909                         rc = -EINTR;
 910                         break;
 911                 }
 912                 set_current_state(TASK_INTERRUPTIBLE);
 913                 rc = usblp_wtest(usblp, nonblock);
 914                 mutex_unlock(&usblp->mut);
 915                 if (rc <= 0)
 916                         break;
 917
 918                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 919                         if (usblp->flags & LP_ABORT) {
 920                                 err = usblp_check_status(usblp, err);
 921                                 if (err == 1) { /* Paper out */
 922                                         rc = -ENOSPC;
 923                                         break;
 924                                 }
 925                         } else {
 926                                 /* Prod the printer, Gentoo#251237. */
 927                                 mutex_lock(&usblp->mut);
 928                                 usblp_read_status(usblp, usblp->statusbuf);
 929                                 mutex_unlock(&usblp->mut);
 930                         }
 931                 }
 932         }
 933         set_current_state(TASK_RUNNING);
 934         remove_wait_queue(&usblp->wwait, &waita);
 935         return rc;
 936 }
 937
 938 static int usblp_wtest(struct usblp *usblp, int nonblock)
 939 {
 940         unsigned long flags;
 941
 942         if (!usblp->present)
 943                 return -ENODEV;
 944         if (signal_pending(current))
 945                 return -EINTR;
 946         spin_lock_irqsave(&usblp->lock, flags);
 947         if (usblp->wcomplete) {
 948                 spin_unlock_irqrestore(&usblp->lock, flags);
 949                 return 0;
 950         }
 951         spin_unlock_irqrestore(&usblp->lock, flags);
 952         if (nonblock)
 953                 return -EAGAIN;
 954         return 1;
 955 }
 956
 957 /*
 958  * Wait for read bytes to become available. This probably should have been
 959  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 960  * name for functions which lock and return.
 961  *
 962  * We do not use wait_event_interruptible because it makes locking iffy.
 963  */
 964 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 965 {
 966         DECLARE_WAITQUEUE(waita, current);
 967         int rc;
 968
 969         add_wait_queue(&usblp->rwait, &waita);
 970         for (;;) {
 971                 if (mutex_lock_interruptible(&usblp->mut)) {
 972                         rc = -EINTR;
 973                         break;
 974                 }
 975                 set_current_state(TASK_INTERRUPTIBLE);
 976                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 977                         mutex_unlock(&usblp->mut);
 978                         break;
 979                 }
 980                 if (rc == 0)    /* Keep it locked */
 981                         break;
 982                 mutex_unlock(&usblp->mut);
 983                 schedule();
 984         }
 985         set_current_state(TASK_RUNNING);
 986         remove_wait_queue(&usblp->rwait, &waita);
 987         return rc;
 988 }
 989
 990 static int usblp_rtest(struct usblp *usblp, int nonblock)
 991 {
 992         unsigned long flags;
 993
 994         if (!usblp->present)
 995                 return -ENODEV;
 996         if (signal_pending(current))
 997                 return -EINTR;
 998         spin_lock_irqsave(&usblp->lock, flags);
 999         if (usblp->rcomplete) {
1000                 spin_unlock_irqrestore(&usblp->lock, flags);
1001                 return 0;
1002         }
1003         spin_unlock_irqrestore(&usblp->lock, flags);
1004         if (nonblock)
1005                 return -EAGAIN;
1006         return 1;
1007 }
1008
1009 /*
1010  * Please check ->bidir and other such things outside for now.
1011  */
1012 static int usblp_submit_read(struct usblp *usblp)
1013 {
1014         struct urb *urb;
1015         unsigned long flags;
1016         int rc;
1017
1018         rc = -ENOMEM;
1019         urb = usb_alloc_urb(0, GFP_KERNEL);
1020         if (urb == NULL)
1021                 goto raise_urb;
1022
1023         usb_fill_bulk_urb(urb, usblp->dev,
1024                 usb_rcvbulkpipe(usblp->dev,
1025                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1026                 usblp->readbuf, USBLP_BUF_SIZE_IN,
1027                 usblp_bulk_read, usblp);
1028         usb_anchor_urb(urb, &usblp->urbs);
1029
1030         spin_lock_irqsave(&usblp->lock, flags);
1031         usblp->readcount = 0; /* XXX Why here? */
1032         usblp->rcomplete = 0;
1033         spin_unlock_irqrestore(&usblp->lock, flags);
1034         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1035                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1036                 spin_lock_irqsave(&usblp->lock, flags);
1037                 usblp->rstatus = rc;
1038                 usblp->rcomplete = 1;
1039                 spin_unlock_irqrestore(&usblp->lock, flags);
1040                 goto raise_submit;
1041         }
1042
1043         return 0;
1044
1045 raise_submit:
1046         usb_unanchor_urb(urb);
1047         usb_free_urb(urb);
1048 raise_urb:
1049         return rc;
1050 }
1051
1052 /*
1053  * Checks for printers that have quirks, such as requiring unidirectional
1054  * communication but reporting bidirectional; currently some HP printers
1055  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1056  * sent at each open (like some Epsons).
1057  * Returns 1 if found, 0 if not found.
1058  *
1059  * HP recommended that we use the bidirectional interface but
1060  * don't attempt any bulk IN transfers from the IN endpoint.
1061  * Here's some more detail on the problem:
1062  * The problem is not that it isn't bidirectional though. The problem
1063  * is that if you request a device ID, or status information, while
1064  * the buffers are full, the return data will end up in the print data
1065  * buffer. For example if you make sure you never request the device ID
1066  * while you are sending print data, and you don't try to query the
1067  * printer status every couple of milliseconds, you will probably be OK.
1068  */
1069 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1070 {
1071         int i;
1072
1073         for (i = 0; quirk_printers[i].vendorId; i++) {
1074                 if (vendor == quirk_printers[i].vendorId &&
1075                     product == quirk_printers[i].productId)
1076                         return quirk_printers[i].quirks;
1077         }
1078         return 0;
1079 }
1080
1081 static const struct file_operations usblp_fops = {
1082         .owner =        THIS_MODULE,
1083         .read =         usblp_read,
1084         .write =        usblp_write,
1085         .poll =         usblp_poll,
1086         .unlocked_ioctl =       usblp_ioctl,
1087         .compat_ioctl =         usblp_ioctl,
1088         .open =         usblp_open,
1089         .release =      usblp_release,
1090         .llseek =       noop_llseek,
1091 };
1092
1093 static char *usblp_devnode(struct device *dev, umode_t *mode)
1094 {
1095         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1096 }
1097
1098 static struct usb_class_driver usblp_class = {
1099         .name =         "lp%d",
1100         .devnode =      usblp_devnode,
1101         .fops =         &usblp_fops,
1102         .minor_base =   USBLP_MINOR_BASE,
1103 };
1104
1105 static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1106 {
1107         struct usb_interface *intf = to_usb_interface(dev);
1108         struct usblp *usblp = usb_get_intfdata(intf);
1109
1110         if (usblp->device_id_string[0] == 0 &&
1111             usblp->device_id_string[1] == 0)
1112                 return 0;
1113
1114         return sprintf(buf, "%s", usblp->device_id_string+2);
1115 }
1116
1117 static DEVICE_ATTR_RO(ieee1284_id);
1118
1119 static int usblp_probe(struct usb_interface *intf,
1120                        const struct usb_device_id *id)
1121 {
1122         struct usb_device *dev = interface_to_usbdev(intf);
1123         struct usblp *usblp;
1124         int protocol;
1125         int retval;
1126
1127         /* Malloc and start initializing usblp structure so we can use it
1128          * directly. */
1129         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1130         if (!usblp) {
1131                 retval = -ENOMEM;
1132                 goto abort_ret;
1133         }
1134         usblp->dev = dev;
1135         mutex_init(&usblp->wmut);
1136         mutex_init(&usblp->mut);
1137         spin_lock_init(&usblp->lock);
1138         init_waitqueue_head(&usblp->rwait);
1139         init_waitqueue_head(&usblp->wwait);
1140         init_usb_anchor(&usblp->urbs);
1141         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1142         usblp->intf = usb_get_intf(intf);
1143
1144         /* Malloc device ID string buffer to the largest expected length,
1145          * since we can re-query it on an ioctl and a dynamic string
1146          * could change in length. */
1147         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1148                 retval = -ENOMEM;
1149                 goto abort;
1150         }
1151
1152         /*
1153          * Allocate read buffer. We somewhat wastefully
1154          * malloc both regardless of bidirectionality, because the
1155          * alternate setting can be changed later via an ioctl.
1156          */
1157         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1158                 retval = -ENOMEM;
1159                 goto abort;
1160         }
1161
1162         /* Allocate buffer for printer status */
1163         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1164         if (!usblp->statusbuf) {
1165                 retval = -ENOMEM;
1166                 goto abort;
1167         }
1168
1169         /* Lookup quirks for this printer. */
1170         usblp->quirks = usblp_quirks(
1171                 le16_to_cpu(dev->descriptor.idVendor),
1172                 le16_to_cpu(dev->descriptor.idProduct));
1173
1174         /* Analyze and pick initial alternate settings and endpoints. */
1175         protocol = usblp_select_alts(usblp);
1176         if (protocol < 0) {
1177                 dev_dbg(&intf->dev,
1178                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1179                         le16_to_cpu(dev->descriptor.idVendor),
1180                         le16_to_cpu(dev->descriptor.idProduct));
1181                 retval = -ENODEV;
1182                 goto abort;
1183         }
1184
1185         /* Setup the selected alternate setting and endpoints. */
1186         if (usblp_set_protocol(usblp, protocol) < 0) {
1187                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1188                 goto abort;
1189         }
1190
1191         /* Retrieve and store the device ID string. */
1192         usblp_cache_device_id_string(usblp);
1193         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1194         if (retval)
1195                 goto abort_intfdata;
1196
1197 #ifdef DEBUG
1198         usblp_check_status(usblp, 0);
1199 #endif
1200
1201         usb_set_intfdata(intf, usblp);
1202
1203         usblp->present = 1;
1204
1205         retval = usb_register_dev(intf, &usblp_class);
1206         if (retval) {
1207                 dev_err(&intf->dev,
1208                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1209                         USBLP_MINOR_BASE, retval);
1210                 goto abort_intfdata;
1211         }
1212         usblp->minor = intf->minor;
1213         dev_info(&intf->dev,
1214                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1215                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1216                 usblp->ifnum,
1217                 usblp->protocol[usblp->current_protocol].alt_setting,
1218                 usblp->current_protocol,
1219                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1220                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1221
1222         return 0;
1223
1224 abort_intfdata:
1225         usb_set_intfdata(intf, NULL);
1226         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1227 abort:
1228         kfree(usblp->readbuf);
1229         kfree(usblp->statusbuf);
1230         kfree(usblp->device_id_string);
1231         usb_put_intf(usblp->intf);
1232         kfree(usblp);
1233 abort_ret:
1234         return retval;
1235 }
1236
1237 /*
1238  * We are a "new" style driver with usb_device_id table,
1239  * but our requirements are too intricate for simple match to handle.
1240  *
1241  * The "proto_bias" option may be used to specify the preferred protocol
1242  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1243  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1244  * then we bind to it.
1245  *
1246  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1247  * is compatible with a stream of characters. If we find it, we bind to it.
1248  *
1249  * Note that the people from hpoj.sourceforge.net need to be able to
1250  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1251  * for this purpose.
1252  *
1253  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1254  * even though it's probably not stream-compatible, because this matches
1255  * the behaviour of the old code.
1256  *
1257  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1258  * - the unidirectional interface.
1259  */
1260 static int usblp_select_alts(struct usblp *usblp)
1261 {
1262         struct usb_interface *if_alt;
1263         struct usb_host_interface *ifd;
1264         struct usb_endpoint_descriptor *epwrite, *epread;
1265         int p, i;
1266         int res;
1267
1268         if_alt = usblp->intf;
1269
1270         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1271                 usblp->protocol[p].alt_setting = -1;
1272
1273         /* Find out what we have. */
1274         for (i = 0; i < if_alt->num_altsetting; i++) {
1275                 ifd = &if_alt->altsetting[i];
1276
1277                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1278                     ifd->desc.bInterfaceSubClass != 1)
1279                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1280                                 continue;
1281
1282                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1283                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1284                         continue;
1285
1286                 /* Look for the expected bulk endpoints. */
1287                 if (ifd->desc.bInterfaceProtocol > 1) {
1288                         res = usb_find_common_endpoints(ifd,
1289                                         &epread, &epwrite, NULL, NULL);
1290                 } else {
1291                         epread = NULL;
1292                         res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1293                 }
1294
1295                 /* Ignore buggy hardware without the right endpoints. */
1296                 if (res)
1297                         continue;
1298
1299                 /* Turn off reads for buggy bidirectional printers. */
1300                 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1301                         printk(KERN_INFO "usblp%d: Disabling reads from "
1302                             "problematic bidirectional printer\n",
1303                             usblp->minor);
1304                         epread = NULL;
1305                 }
1306
1307                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1308                                 ifd->desc.bAlternateSetting;
1309                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1310                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1311         }
1312
1313         /* If our requested protocol is supported, then use it. */
1314         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1315             proto_bias <= USBLP_LAST_PROTOCOL &&
1316             usblp->protocol[proto_bias].alt_setting != -1)
1317                 return proto_bias;
1318
1319         /* Ordering is important here. */
1320         if (usblp->protocol[2].alt_setting != -1)
1321                 return 2;
1322         if (usblp->protocol[1].alt_setting != -1)
1323                 return 1;
1324         if (usblp->protocol[3].alt_setting != -1)
1325                 return 3;
1326
1327         /* If nothing is available, then don't bind to this device. */
1328         return -1;
1329 }
1330
1331 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1332 {
1333         int r, alts;
1334
1335         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1336                 return -EINVAL;
1337
1338         /* Don't unnecessarily set the interface if there's a single alt. */
1339         if (usblp->intf->num_altsetting > 1) {
1340                 alts = usblp->protocol[protocol].alt_setting;
1341                 if (alts < 0)
1342                         return -EINVAL;
1343                 r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1344                 if (r < 0) {
1345                         printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1346                                 alts, usblp->ifnum);
1347                         return r;
1348                 }
1349         }
1350
1351         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1352         usblp->current_protocol = protocol;
1353         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1354                 usblp->minor, protocol);
1355         return 0;
1356 }
1357
1358 /* Retrieves and caches device ID string.
1359  * Returns length, including length bytes but not null terminator.
1360  * On error, returns a negative errno value. */
1361 static int usblp_cache_device_id_string(struct usblp *usblp)
1362 {
1363         int err, length;
1364
1365         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1366         if (err < 0) {
1367                 dev_dbg(&usblp->intf->dev,
1368                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1369                         usblp->minor, err);
1370                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1371                 return -EIO;
1372         }
1373
1374         /* First two bytes are length in big-endian.
1375          * They count themselves, and we copy them into
1376          * the user's buffer. */
1377         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1378         if (length < 2)
1379                 length = 2;
1380         else if (length >= USBLP_DEVICE_ID_SIZE)
1381                 length = USBLP_DEVICE_ID_SIZE - 1;
1382         usblp->device_id_string[length] = '\0';
1383
1384         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1385                 usblp->minor, length, &usblp->device_id_string[2]);
1386
1387         return length;
1388 }
1389
1390 static void usblp_disconnect(struct usb_interface *intf)
1391 {
1392         struct usblp *usblp = usb_get_intfdata(intf);
1393
1394         usb_deregister_dev(intf, &usblp_class);
1395
1396         if (!usblp || !usblp->dev) {
1397                 dev_err(&intf->dev, "bogus disconnect\n");
1398                 BUG();
1399         }
1400
1401         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1402
1403         mutex_lock(&usblp_mutex);
1404         mutex_lock(&usblp->mut);
1405         usblp->present = 0;
1406         wake_up(&usblp->wwait);
1407         wake_up(&usblp->rwait);
1408         usb_set_intfdata(intf, NULL);
1409
1410         usblp_unlink_urbs(usblp);
1411         mutex_unlock(&usblp->mut);
1412         usb_poison_anchored_urbs(&usblp->urbs);
1413
1414         if (!usblp->used)
1415                 usblp_cleanup(usblp);
1416
1417         mutex_unlock(&usblp_mutex);
1418 }
1419
1420 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1421 {
1422         struct usblp *usblp = usb_get_intfdata(intf);
1423
1424         usblp_unlink_urbs(usblp);
1425 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1426         /* not strictly necessary, but just in case */
1427         wake_up(&usblp->wwait);
1428         wake_up(&usblp->rwait);
1429 #endif
1430
1431         return 0;
1432 }
1433
1434 static int usblp_resume(struct usb_interface *intf)
1435 {
1436         struct usblp *usblp = usb_get_intfdata(intf);
1437         int r;
1438
1439         r = handle_bidir(usblp);
1440
1441         return r;
1442 }
1443
1444 static const struct usb_device_id usblp_ids[] = {
1445         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1446         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1447         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1448         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1449         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1450         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1451         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1452         { }                                             /* Terminating entry */
1453 };
1454
1455 MODULE_DEVICE_TABLE(usb, usblp_ids);
1456
1457 static struct usb_driver usblp_driver = {
1458         .name =         "usblp",
1459         .probe =        usblp_probe,
1460         .disconnect =   usblp_disconnect,
1461         .suspend =      usblp_suspend,
1462         .resume =       usblp_resume,
1463         .id_table =     usblp_ids,
1464         .supports_autosuspend = 1,
1465 };
1466
1467 module_usb_driver(usblp_driver);
1468
1469 MODULE_AUTHOR(DRIVER_AUTHOR);
1470 MODULE_DESCRIPTION(DRIVER_DESC);
1471 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1472 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1473 MODULE_LICENSE("GPL");