drivers/usb/gadget/composite.c

   1 /*
   2  * composite.c - infrastructure for Composite USB Gadgets
   3  *
   4  * Copyright (C) 2006-2008 David Brownell
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 /* #define VERBOSE_DEBUG */
  13
  14 #include <linux/kallsyms.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/device.h>
  19 #include <linux/utsname.h>
  20
  21 #include <linux/usb/composite.h>
  22 #include <linux/usb/otg.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "u_os_desc.h"
  26
  27 /**
  28  * struct usb_os_string - represents OS String to be reported by a gadget
  29  * @bLength: total length of the entire descritor, always 0x12
  30  * @bDescriptorType: USB_DT_STRING
  31  * @qwSignature: the OS String proper
  32  * @bMS_VendorCode: code used by the host for subsequent requests
  33  * @bPad: not used, must be zero
  34  */
  35 struct usb_os_string {
  36         __u8    bLength;
  37         __u8    bDescriptorType;
  38         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  39         __u8    bMS_VendorCode;
  40         __u8    bPad;
  41 } __packed;
  42
  43 /*
  44  * The code in this file is utility code, used to build a gadget driver
  45  * from one or more "function" drivers, one or more "configuration"
  46  * objects, and a "usb_composite_driver" by gluing them together along
  47  * with the relevant device-wide data.
  48  */
  49
  50 static struct usb_gadget_strings **get_containers_gs(
  51                 struct usb_gadget_string_container *uc)
  52 {
  53         return (struct usb_gadget_strings **)uc->stash;
  54 }
  55
  56 /**
  57  * next_ep_desc() - advance to the next EP descriptor
  58  * @t: currect pointer within descriptor array
  59  *
  60  * Return: next EP descriptor or NULL
  61  *
  62  * Iterate over @t until either EP descriptor found or
  63  * NULL (that indicates end of list) encountered
  64  */
  65 static struct usb_descriptor_header**
  66 next_ep_desc(struct usb_descriptor_header **t)
  67 {
  68         for (; *t; t++) {
  69                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
  70                         return t;
  71         }
  72         return NULL;
  73 }
  74
  75 /*
  76  * for_each_ep_desc()- iterate over endpoint descriptors in the
  77  *              descriptors list
  78  * @start:      pointer within descriptor array.
  79  * @ep_desc:    endpoint descriptor to use as the loop cursor
  80  */
  81 #define for_each_ep_desc(start, ep_desc) \
  82         for (ep_desc = next_ep_desc(start); \
  83               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
  84
  85 /**
  86  * config_ep_by_speed() - configures the given endpoint
  87  * according to gadget speed.
  88  * @g: pointer to the gadget
  89  * @f: usb function
  90  * @_ep: the endpoint to configure
  91  *
  92  * Return: error code, 0 on success
  93  *
  94  * This function chooses the right descriptors for a given
  95  * endpoint according to gadget speed and saves it in the
  96  * endpoint desc field. If the endpoint already has a descriptor
  97  * assigned to it - overwrites it with currently corresponding
  98  * descriptor. The endpoint maxpacket field is updated according
  99  * to the chosen descriptor.
 100  * Note: the supplied function should hold all the descriptors
 101  * for supported speeds
 102  */
 103 int config_ep_by_speed(struct usb_gadget *g,
 104                         struct usb_function *f,
 105                         struct usb_ep *_ep)
 106 {
 107         struct usb_endpoint_descriptor *chosen_desc = NULL;
 108         struct usb_descriptor_header **speed_desc = NULL;
 109
 110         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 111         int want_comp_desc = 0;
 112
 113         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 114
 115         if (!g || !f || !_ep)
 116                 return -EIO;
 117
 118         /* select desired speed */
 119         switch (g->speed) {
 120         case USB_SPEED_SUPER:
 121                 if (gadget_is_superspeed(g)) {
 122                         speed_desc = f->ss_descriptors;
 123                         want_comp_desc = 1;
 124                         break;
 125                 }
 126                 /* else: Fall trough */
 127         case USB_SPEED_HIGH:
 128                 if (gadget_is_dualspeed(g)) {
 129                         speed_desc = f->hs_descriptors;
 130                         break;
 131                 }
 132                 /* else: fall through */
 133         default:
 134                 speed_desc = f->fs_descriptors;
 135         }
 136         /* find descriptors */
 137         for_each_ep_desc(speed_desc, d_spd) {
 138                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 139                 if (chosen_desc->bEndpointAddress == _ep->address)
 140                         goto ep_found;
 141         }
 142         return -EIO;
 143
 144 ep_found:
 145         /* commit results */
 146         _ep->maxpacket = usb_endpoint_maxp(chosen_desc) & 0x7ff;
 147         _ep->desc = chosen_desc;
 148         _ep->comp_desc = NULL;
 149         _ep->maxburst = 0;
 150         _ep->mult = 1;
 151
 152         if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 153                                 usb_endpoint_xfer_int(_ep->desc)))
 154                 _ep->mult = ((usb_endpoint_maxp(_ep->desc) & 0x1800) >> 11) + 1;
 155
 156         if (!want_comp_desc)
 157                 return 0;
 158
 159         /*
 160          * Companion descriptor should follow EP descriptor
 161          * USB 3.0 spec, #9.6.7
 162          */
 163         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 164         if (!comp_desc ||
 165             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 166                 return -EIO;
 167         _ep->comp_desc = comp_desc;
 168         if (g->speed == USB_SPEED_SUPER) {
 169                 switch (usb_endpoint_type(_ep->desc)) {
 170                 case USB_ENDPOINT_XFER_ISOC:
 171                         /* mult: bits 1:0 of bmAttributes */
 172                         _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 173                 case USB_ENDPOINT_XFER_BULK:
 174                 case USB_ENDPOINT_XFER_INT:
 175                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 176                         break;
 177                 default:
 178                         if (comp_desc->bMaxBurst != 0) {
 179                                 struct usb_composite_dev *cdev;
 180
 181                                 cdev = get_gadget_data(g);
 182                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 183                         }
 184                         _ep->maxburst = 1;
 185                         break;
 186                 }
 187         }
 188         return 0;
 189 }
 190 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 191
 192 /**
 193  * usb_add_function() - add a function to a configuration
 194  * @config: the configuration
 195  * @function: the function being added
 196  * Context: single threaded during gadget setup
 197  *
 198  * After initialization, each configuration must have one or more
 199  * functions added to it.  Adding a function involves calling its @bind()
 200  * method to allocate resources such as interface and string identifiers
 201  * and endpoints.
 202  *
 203  * This function returns the value of the function's bind(), which is
 204  * zero for success else a negative errno value.
 205  */
 206 int usb_add_function(struct usb_configuration *config,
 207                 struct usb_function *function)
 208 {
 209         int     value = -EINVAL;
 210
 211         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 212                         function->name, function,
 213                         config->label, config);
 214
 215         if (!function->set_alt || !function->disable)
 216                 goto done;
 217
 218         function->config = config;
 219         list_add_tail(&function->list, &config->functions);
 220
 221         if (function->bind_deactivated) {
 222                 value = usb_function_deactivate(function);
 223                 if (value)
 224                         goto done;
 225         }
 226
 227         /* REVISIT *require* function->bind? */
 228         if (function->bind) {
 229                 value = function->bind(config, function);
 230                 if (value < 0) {
 231                         list_del(&function->list);
 232                         function->config = NULL;
 233                 }
 234         } else
 235                 value = 0;
 236
 237         /* We allow configurations that don't work at both speeds.
 238          * If we run into a lowspeed Linux system, treat it the same
 239          * as full speed ... it's the function drivers that will need
 240          * to avoid bulk and ISO transfers.
 241          */
 242         if (!config->fullspeed && function->fs_descriptors)
 243                 config->fullspeed = true;
 244         if (!config->highspeed && function->hs_descriptors)
 245                 config->highspeed = true;
 246         if (!config->superspeed && function->ss_descriptors)
 247                 config->superspeed = true;
 248
 249 done:
 250         if (value)
 251                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 252                                 function->name, function, value);
 253         return value;
 254 }
 255 EXPORT_SYMBOL_GPL(usb_add_function);
 256
 257 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 258 {
 259         if (f->disable)
 260                 f->disable(f);
 261
 262         bitmap_zero(f->endpoints, 32);
 263         list_del(&f->list);
 264         if (f->unbind)
 265                 f->unbind(c, f);
 266 }
 267 EXPORT_SYMBOL_GPL(usb_remove_function);
 268
 269 /**
 270  * usb_function_deactivate - prevent function and gadget enumeration
 271  * @function: the function that isn't yet ready to respond
 272  *
 273  * Blocks response of the gadget driver to host enumeration by
 274  * preventing the data line pullup from being activated.  This is
 275  * normally called during @bind() processing to change from the
 276  * initial "ready to respond" state, or when a required resource
 277  * becomes available.
 278  *
 279  * For example, drivers that serve as a passthrough to a userspace
 280  * daemon can block enumeration unless that daemon (such as an OBEX,
 281  * MTP, or print server) is ready to handle host requests.
 282  *
 283  * Not all systems support software control of their USB peripheral
 284  * data pullups.
 285  *
 286  * Returns zero on success, else negative errno.
 287  */
 288 int usb_function_deactivate(struct usb_function *function)
 289 {
 290         struct usb_composite_dev        *cdev = function->config->cdev;
 291         unsigned long                   flags;
 292         int                             status = 0;
 293
 294         spin_lock_irqsave(&cdev->lock, flags);
 295
 296         if (cdev->deactivations == 0) {
 297                 spin_unlock_irqrestore(&cdev->lock, flags);
 298                 status = usb_gadget_deactivate(cdev->gadget);
 299                 spin_lock_irqsave(&cdev->lock, flags);
 300         }
 301         if (status == 0)
 302                 cdev->deactivations++;
 303
 304         spin_unlock_irqrestore(&cdev->lock, flags);
 305         return status;
 306 }
 307 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 308
 309 /**
 310  * usb_function_activate - allow function and gadget enumeration
 311  * @function: function on which usb_function_activate() was called
 312  *
 313  * Reverses effect of usb_function_deactivate().  If no more functions
 314  * are delaying their activation, the gadget driver will respond to
 315  * host enumeration procedures.
 316  *
 317  * Returns zero on success, else negative errno.
 318  */
 319 int usb_function_activate(struct usb_function *function)
 320 {
 321         struct usb_composite_dev        *cdev = function->config->cdev;
 322         unsigned long                   flags;
 323         int                             status = 0;
 324
 325         spin_lock_irqsave(&cdev->lock, flags);
 326
 327         if (WARN_ON(cdev->deactivations == 0))
 328                 status = -EINVAL;
 329         else {
 330                 cdev->deactivations--;
 331                 if (cdev->deactivations == 0) {
 332                         spin_unlock_irqrestore(&cdev->lock, flags);
 333                         status = usb_gadget_activate(cdev->gadget);
 334                         spin_lock_irqsave(&cdev->lock, flags);
 335                 }
 336         }
 337
 338         spin_unlock_irqrestore(&cdev->lock, flags);
 339         return status;
 340 }
 341 EXPORT_SYMBOL_GPL(usb_function_activate);
 342
 343 /**
 344  * usb_interface_id() - allocate an unused interface ID
 345  * @config: configuration associated with the interface
 346  * @function: function handling the interface
 347  * Context: single threaded during gadget setup
 348  *
 349  * usb_interface_id() is called from usb_function.bind() callbacks to
 350  * allocate new interface IDs.  The function driver will then store that
 351  * ID in interface, association, CDC union, and other descriptors.  It
 352  * will also handle any control requests targeted at that interface,
 353  * particularly changing its altsetting via set_alt().  There may
 354  * also be class-specific or vendor-specific requests to handle.
 355  *
 356  * All interface identifier should be allocated using this routine, to
 357  * ensure that for example different functions don't wrongly assign
 358  * different meanings to the same identifier.  Note that since interface
 359  * identifiers are configuration-specific, functions used in more than
 360  * one configuration (or more than once in a given configuration) need
 361  * multiple versions of the relevant descriptors.
 362  *
 363  * Returns the interface ID which was allocated; or -ENODEV if no
 364  * more interface IDs can be allocated.
 365  */
 366 int usb_interface_id(struct usb_configuration *config,
 367                 struct usb_function *function)
 368 {
 369         unsigned id = config->next_interface_id;
 370
 371         if (id < MAX_CONFIG_INTERFACES) {
 372                 config->interface[id] = function;
 373                 config->next_interface_id = id + 1;
 374                 return id;
 375         }
 376         return -ENODEV;
 377 }
 378 EXPORT_SYMBOL_GPL(usb_interface_id);
 379
 380 static u8 encode_bMaxPower(enum usb_device_speed speed,
 381                 struct usb_configuration *c)
 382 {
 383         unsigned val;
 384
 385         if (c->MaxPower)
 386                 val = c->MaxPower;
 387         else
 388                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 389         if (!val)
 390                 return 0;
 391         switch (speed) {
 392         case USB_SPEED_SUPER:
 393                 return DIV_ROUND_UP(val, 8);
 394         default:
 395                 return DIV_ROUND_UP(val, 2);
 396         }
 397 }
 398
 399 static int config_buf(struct usb_configuration *config,
 400                 enum usb_device_speed speed, void *buf, u8 type)
 401 {
 402         struct usb_config_descriptor    *c = buf;
 403         void                            *next = buf + USB_DT_CONFIG_SIZE;
 404         int                             len;
 405         struct usb_function             *f;
 406         int                             status;
 407
 408         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 409         /* write the config descriptor */
 410         c = buf;
 411         c->bLength = USB_DT_CONFIG_SIZE;
 412         c->bDescriptorType = type;
 413         /* wTotalLength is written later */
 414         c->bNumInterfaces = config->next_interface_id;
 415         c->bConfigurationValue = config->bConfigurationValue;
 416         c->iConfiguration = config->iConfiguration;
 417         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 418         c->bMaxPower = encode_bMaxPower(speed, config);
 419
 420         /* There may be e.g. OTG descriptors */
 421         if (config->descriptors) {
 422                 status = usb_descriptor_fillbuf(next, len,
 423                                 config->descriptors);
 424                 if (status < 0)
 425                         return status;
 426                 len -= status;
 427                 next += status;
 428         }
 429
 430         /* add each function's descriptors */
 431         list_for_each_entry(f, &config->functions, list) {
 432                 struct usb_descriptor_header **descriptors;
 433
 434                 switch (speed) {
 435                 case USB_SPEED_SUPER:
 436                         descriptors = f->ss_descriptors;
 437                         break;
 438                 case USB_SPEED_HIGH:
 439                         descriptors = f->hs_descriptors;
 440                         break;
 441                 default:
 442                         descriptors = f->fs_descriptors;
 443                 }
 444
 445                 if (!descriptors)
 446                         continue;
 447                 status = usb_descriptor_fillbuf(next, len,
 448                         (const struct usb_descriptor_header **) descriptors);
 449                 if (status < 0)
 450                         return status;
 451                 len -= status;
 452                 next += status;
 453         }
 454
 455         len = next - buf;
 456         c->wTotalLength = cpu_to_le16(len);
 457         return len;
 458 }
 459
 460 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 461 {
 462         struct usb_gadget               *gadget = cdev->gadget;
 463         struct usb_configuration        *c;
 464         struct list_head                *pos;
 465         u8                              type = w_value >> 8;
 466         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 467
 468         if (gadget->speed == USB_SPEED_SUPER)
 469                 speed = gadget->speed;
 470         else if (gadget_is_dualspeed(gadget)) {
 471                 int     hs = 0;
 472                 if (gadget->speed == USB_SPEED_HIGH)
 473                         hs = 1;
 474                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 475                         hs = !hs;
 476                 if (hs)
 477                         speed = USB_SPEED_HIGH;
 478
 479         }
 480
 481         /* This is a lookup by config *INDEX* */
 482         w_value &= 0xff;
 483
 484         pos = &cdev->configs;
 485         c = cdev->os_desc_config;
 486         if (c)
 487                 goto check_config;
 488
 489         while ((pos = pos->next) !=  &cdev->configs) {
 490                 c = list_entry(pos, typeof(*c), list);
 491
 492                 /* skip OS Descriptors config which is handled separately */
 493                 if (c == cdev->os_desc_config)
 494                         continue;
 495
 496 check_config:
 497                 /* ignore configs that won't work at this speed */
 498                 switch (speed) {
 499                 case USB_SPEED_SUPER:
 500                         if (!c->superspeed)
 501                                 continue;
 502                         break;
 503                 case USB_SPEED_HIGH:
 504                         if (!c->highspeed)
 505                                 continue;
 506                         break;
 507                 default:
 508                         if (!c->fullspeed)
 509                                 continue;
 510                 }
 511
 512                 if (w_value == 0)
 513                         return config_buf(c, speed, cdev->req->buf, type);
 514                 w_value--;
 515         }
 516         return -EINVAL;
 517 }
 518
 519 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 520 {
 521         struct usb_gadget               *gadget = cdev->gadget;
 522         struct usb_configuration        *c;
 523         unsigned                        count = 0;
 524         int                             hs = 0;
 525         int                             ss = 0;
 526
 527         if (gadget_is_dualspeed(gadget)) {
 528                 if (gadget->speed == USB_SPEED_HIGH)
 529                         hs = 1;
 530                 if (gadget->speed == USB_SPEED_SUPER)
 531                         ss = 1;
 532                 if (type == USB_DT_DEVICE_QUALIFIER)
 533                         hs = !hs;
 534         }
 535         list_for_each_entry(c, &cdev->configs, list) {
 536                 /* ignore configs that won't work at this speed */
 537                 if (ss) {
 538                         if (!c->superspeed)
 539                                 continue;
 540                 } else if (hs) {
 541                         if (!c->highspeed)
 542                                 continue;
 543                 } else {
 544                         if (!c->fullspeed)
 545                                 continue;
 546                 }
 547                 count++;
 548         }
 549         return count;
 550 }
 551
 552 /**
 553  * bos_desc() - prepares the BOS descriptor.
 554  * @cdev: pointer to usb_composite device to generate the bos
 555  *      descriptor for
 556  *
 557  * This function generates the BOS (Binary Device Object)
 558  * descriptor and its device capabilities descriptors. The BOS
 559  * descriptor should be supported by a SuperSpeed device.
 560  */
 561 static int bos_desc(struct usb_composite_dev *cdev)
 562 {
 563         struct usb_ext_cap_descriptor   *usb_ext;
 564         struct usb_ss_cap_descriptor    *ss_cap;
 565         struct usb_dcd_config_params    dcd_config_params;
 566         struct usb_bos_descriptor       *bos = cdev->req->buf;
 567
 568         bos->bLength = USB_DT_BOS_SIZE;
 569         bos->bDescriptorType = USB_DT_BOS;
 570
 571         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 572         bos->bNumDeviceCaps = 0;
 573
 574         /*
 575          * A SuperSpeed device shall include the USB2.0 extension descriptor
 576          * and shall support LPM when operating in USB2.0 HS mode.
 577          */
 578         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 579         bos->bNumDeviceCaps++;
 580         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 581         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 582         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 583         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 584         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | USB_BESL_SUPPORT);
 585
 586         /*
 587          * The Superspeed USB Capability descriptor shall be implemented by all
 588          * SuperSpeed devices.
 589          */
 590         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 591         bos->bNumDeviceCaps++;
 592         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 593         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 594         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 595         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 596         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 597         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 598                                 USB_FULL_SPEED_OPERATION |
 599                                 USB_HIGH_SPEED_OPERATION |
 600                                 USB_5GBPS_OPERATION);
 601         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 602
 603         /* Get Controller configuration */
 604         if (cdev->gadget->ops->get_config_params)
 605                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 606         else {
 607                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 608                 dcd_config_params.bU2DevExitLat =
 609                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 610         }
 611         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 612         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 613
 614         return le16_to_cpu(bos->wTotalLength);
 615 }
 616
 617 static void device_qual(struct usb_composite_dev *cdev)
 618 {
 619         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 620
 621         qual->bLength = sizeof(*qual);
 622         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 623         /* POLICY: same bcdUSB and device type info at both speeds */
 624         qual->bcdUSB = cdev->desc.bcdUSB;
 625         qual->bDeviceClass = cdev->desc.bDeviceClass;
 626         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 627         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 628         /* ASSUME same EP0 fifo size at both speeds */
 629         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 630         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 631         qual->bRESERVED = 0;
 632 }
 633
 634 /*-------------------------------------------------------------------------*/
 635
 636 static void reset_config(struct usb_composite_dev *cdev)
 637 {
 638         struct usb_function             *f;
 639
 640         DBG(cdev, "reset config\n");
 641
 642         list_for_each_entry(f, &cdev->config->functions, list) {
 643                 if (f->disable)
 644                         f->disable(f);
 645
 646                 bitmap_zero(f->endpoints, 32);
 647         }
 648         cdev->config = NULL;
 649         cdev->delayed_status = 0;
 650 }
 651
 652 static int set_config(struct usb_composite_dev *cdev,
 653                 const struct usb_ctrlrequest *ctrl, unsigned number)
 654 {
 655         struct usb_gadget       *gadget = cdev->gadget;
 656         struct usb_configuration *c = NULL;
 657         int                     result = -EINVAL;
 658         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 659         int                     tmp;
 660
 661         if (number) {
 662                 list_for_each_entry(c, &cdev->configs, list) {
 663                         if (c->bConfigurationValue == number) {
 664                                 /*
 665                                  * We disable the FDs of the previous
 666                                  * configuration only if the new configuration
 667                                  * is a valid one
 668                                  */
 669                                 if (cdev->config)
 670                                         reset_config(cdev);
 671                                 result = 0;
 672                                 break;
 673                         }
 674                 }
 675                 if (result < 0)
 676                         goto done;
 677         } else { /* Zero configuration value - need to reset the config */
 678                 if (cdev->config)
 679                         reset_config(cdev);
 680                 result = 0;
 681         }
 682
 683         INFO(cdev, "%s config #%d: %s\n",
 684              usb_speed_string(gadget->speed),
 685              number, c ? c->label : "unconfigured");
 686
 687         if (!c)
 688                 goto done;
 689
 690         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 691         cdev->config = c;
 692
 693         /* Initialize all interfaces by setting them to altsetting zero. */
 694         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 695                 struct usb_function     *f = c->interface[tmp];
 696                 struct usb_descriptor_header **descriptors;
 697
 698                 if (!f)
 699                         break;
 700
 701                 /*
 702                  * Record which endpoints are used by the function. This is used
 703                  * to dispatch control requests targeted at that endpoint to the
 704                  * function's setup callback instead of the current
 705                  * configuration's setup callback.
 706                  */
 707                 switch (gadget->speed) {
 708                 case USB_SPEED_SUPER:
 709                         descriptors = f->ss_descriptors;
 710                         break;
 711                 case USB_SPEED_HIGH:
 712                         descriptors = f->hs_descriptors;
 713                         break;
 714                 default:
 715                         descriptors = f->fs_descriptors;
 716                 }
 717
 718                 for (; *descriptors; ++descriptors) {
 719                         struct usb_endpoint_descriptor *ep;
 720                         int addr;
 721
 722                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 723                                 continue;
 724
 725                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 726                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 727                              |  (ep->bEndpointAddress & 0x0f);
 728                         set_bit(addr, f->endpoints);
 729                 }
 730
 731                 result = f->set_alt(f, tmp, 0);
 732                 if (result < 0) {
 733                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 734                                         tmp, f->name, f, result);
 735
 736                         reset_config(cdev);
 737                         goto done;
 738                 }
 739
 740                 if (result == USB_GADGET_DELAYED_STATUS) {
 741                         DBG(cdev,
 742                          "%s: interface %d (%s) requested delayed status\n",
 743                                         __func__, tmp, f->name);
 744                         cdev->delayed_status++;
 745                         DBG(cdev, "delayed_status count %d\n",
 746                                         cdev->delayed_status);
 747                 }
 748         }
 749
 750         /* when we return, be sure our power usage is valid */
 751         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 752 done:
 753         if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
 754                 usb_gadget_set_selfpowered(gadget);
 755         else
 756                 usb_gadget_clear_selfpowered(gadget);
 757
 758         usb_gadget_vbus_draw(gadget, power);
 759         if (result >= 0 && cdev->delayed_status)
 760                 result = USB_GADGET_DELAYED_STATUS;
 761         return result;
 762 }
 763
 764 int usb_add_config_only(struct usb_composite_dev *cdev,
 765                 struct usb_configuration *config)
 766 {
 767         struct usb_configuration *c;
 768
 769         if (!config->bConfigurationValue)
 770                 return -EINVAL;
 771
 772         /* Prevent duplicate configuration identifiers */
 773         list_for_each_entry(c, &cdev->configs, list) {
 774                 if (c->bConfigurationValue == config->bConfigurationValue)
 775                         return -EBUSY;
 776         }
 777
 778         config->cdev = cdev;
 779         list_add_tail(&config->list, &cdev->configs);
 780
 781         INIT_LIST_HEAD(&config->functions);
 782         config->next_interface_id = 0;
 783         memset(config->interface, 0, sizeof(config->interface));
 784
 785         return 0;
 786 }
 787 EXPORT_SYMBOL_GPL(usb_add_config_only);
 788
 789 /**
 790  * usb_add_config() - add a configuration to a device.
 791  * @cdev: wraps the USB gadget
 792  * @config: the configuration, with bConfigurationValue assigned
 793  * @bind: the configuration's bind function
 794  * Context: single threaded during gadget setup
 795  *
 796  * One of the main tasks of a composite @bind() routine is to
 797  * add each of the configurations it supports, using this routine.
 798  *
 799  * This function returns the value of the configuration's @bind(), which
 800  * is zero for success else a negative errno value.  Binding configurations
 801  * assigns global resources including string IDs, and per-configuration
 802  * resources such as interface IDs and endpoints.
 803  */
 804 int usb_add_config(struct usb_composite_dev *cdev,
 805                 struct usb_configuration *config,
 806                 int (*bind)(struct usb_configuration *))
 807 {
 808         int                             status = -EINVAL;
 809
 810         if (!bind)
 811                 goto done;
 812
 813         DBG(cdev, "adding config #%u '%s'/%p\n",
 814                         config->bConfigurationValue,
 815                         config->label, config);
 816
 817         status = usb_add_config_only(cdev, config);
 818         if (status)
 819                 goto done;
 820
 821         status = bind(config);
 822         if (status < 0) {
 823                 while (!list_empty(&config->functions)) {
 824                         struct usb_function             *f;
 825
 826                         f = list_first_entry(&config->functions,
 827                                         struct usb_function, list);
 828                         list_del(&f->list);
 829                         if (f->unbind) {
 830                                 DBG(cdev, "unbind function '%s'/%p\n",
 831                                         f->name, f);
 832                                 f->unbind(config, f);
 833                                 /* may free memory for "f" */
 834                         }
 835                 }
 836                 list_del(&config->list);
 837                 config->cdev = NULL;
 838         } else {
 839                 unsigned        i;
 840
 841                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 842                         config->bConfigurationValue, config,
 843                         config->superspeed ? " super" : "",
 844                         config->highspeed ? " high" : "",
 845                         config->fullspeed
 846                                 ? (gadget_is_dualspeed(cdev->gadget)
 847                                         ? " full"
 848                                         : " full/low")
 849                                 : "");
 850
 851                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 852                         struct usb_function     *f = config->interface[i];
 853
 854                         if (!f)
 855                                 continue;
 856                         DBG(cdev, "  interface %d = %s/%p\n",
 857                                 i, f->name, f);
 858                 }
 859         }
 860
 861         /* set_alt(), or next bind(), sets up ep->claimed as needed */
 862         usb_ep_autoconfig_reset(cdev->gadget);
 863
 864 done:
 865         if (status)
 866                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 867                                 config->bConfigurationValue, status);
 868         return status;
 869 }
 870 EXPORT_SYMBOL_GPL(usb_add_config);
 871
 872 static void remove_config(struct usb_composite_dev *cdev,
 873                               struct usb_configuration *config)
 874 {
 875         while (!list_empty(&config->functions)) {
 876                 struct usb_function             *f;
 877
 878                 f = list_first_entry(&config->functions,
 879                                 struct usb_function, list);
 880                 list_del(&f->list);
 881                 if (f->unbind) {
 882                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 883                         f->unbind(config, f);
 884                         /* may free memory for "f" */
 885                 }
 886         }
 887         list_del(&config->list);
 888         if (config->unbind) {
 889                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 890                 config->unbind(config);
 891                         /* may free memory for "c" */
 892         }
 893 }
 894
 895 /**
 896  * usb_remove_config() - remove a configuration from a device.
 897  * @cdev: wraps the USB gadget
 898  * @config: the configuration
 899  *
 900  * Drivers must call usb_gadget_disconnect before calling this function
 901  * to disconnect the device from the host and make sure the host will not
 902  * try to enumerate the device while we are changing the config list.
 903  */
 904 void usb_remove_config(struct usb_composite_dev *cdev,
 905                       struct usb_configuration *config)
 906 {
 907         unsigned long flags;
 908
 909         spin_lock_irqsave(&cdev->lock, flags);
 910
 911         if (cdev->config == config)
 912                 reset_config(cdev);
 913
 914         spin_unlock_irqrestore(&cdev->lock, flags);
 915
 916         remove_config(cdev, config);
 917 }
 918
 919 /*-------------------------------------------------------------------------*/
 920
 921 /* We support strings in multiple languages ... string descriptor zero
 922  * says which languages are supported.  The typical case will be that
 923  * only one language (probably English) is used, with i18n handled on
 924  * the host side.
 925  */
 926
 927 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 928 {
 929         const struct usb_gadget_strings *s;
 930         __le16                          language;
 931         __le16                          *tmp;
 932
 933         while (*sp) {
 934                 s = *sp;
 935                 language = cpu_to_le16(s->language);
 936                 for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
 937                         if (*tmp == language)
 938                                 goto repeat;
 939                 }
 940                 *tmp++ = language;
 941 repeat:
 942                 sp++;
 943         }
 944 }
 945
 946 static int lookup_string(
 947         struct usb_gadget_strings       **sp,
 948         void                            *buf,
 949         u16                             language,
 950         int                             id
 951 )
 952 {
 953         struct usb_gadget_strings       *s;
 954         int                             value;
 955
 956         while (*sp) {
 957                 s = *sp++;
 958                 if (s->language != language)
 959                         continue;
 960                 value = usb_gadget_get_string(s, id, buf);
 961                 if (value > 0)
 962                         return value;
 963         }
 964         return -EINVAL;
 965 }
 966
 967 static int get_string(struct usb_composite_dev *cdev,
 968                 void *buf, u16 language, int id)
 969 {
 970         struct usb_composite_driver     *composite = cdev->driver;
 971         struct usb_gadget_string_container *uc;
 972         struct usb_configuration        *c;
 973         struct usb_function             *f;
 974         int                             len;
 975
 976         /* Yes, not only is USB's i18n support probably more than most
 977          * folk will ever care about ... also, it's all supported here.
 978          * (Except for UTF8 support for Unicode's "Astral Planes".)
 979          */
 980
 981         /* 0 == report all available language codes */
 982         if (id == 0) {
 983                 struct usb_string_descriptor    *s = buf;
 984                 struct usb_gadget_strings       **sp;
 985
 986                 memset(s, 0, 256);
 987                 s->bDescriptorType = USB_DT_STRING;
 988
 989                 sp = composite->strings;
 990                 if (sp)
 991                         collect_langs(sp, s->wData);
 992
 993                 list_for_each_entry(c, &cdev->configs, list) {
 994                         sp = c->strings;
 995                         if (sp)
 996                                 collect_langs(sp, s->wData);
 997
 998                         list_for_each_entry(f, &c->functions, list) {
 999                                 sp = f->strings;
1000                                 if (sp)
1001                                         collect_langs(sp, s->wData);
1002                         }
1003                 }
1004                 list_for_each_entry(uc, &cdev->gstrings, list) {
1005                         struct usb_gadget_strings **sp;
1006
1007                         sp = get_containers_gs(uc);
1008                         collect_langs(sp, s->wData);
1009                 }
1010
1011                 for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1012                         continue;
1013                 if (!len)
1014                         return -EINVAL;
1015
1016                 s->bLength = 2 * (len + 1);
1017                 return s->bLength;
1018         }
1019
1020         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1021                 struct usb_os_string *b = buf;
1022                 b->bLength = sizeof(*b);
1023                 b->bDescriptorType = USB_DT_STRING;
1024                 compiletime_assert(
1025                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1026                         "qwSignature size must be equal to qw_sign");
1027                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1028                 b->bMS_VendorCode = cdev->b_vendor_code;
1029                 b->bPad = 0;
1030                 return sizeof(*b);
1031         }
1032
1033         list_for_each_entry(uc, &cdev->gstrings, list) {
1034                 struct usb_gadget_strings **sp;
1035
1036                 sp = get_containers_gs(uc);
1037                 len = lookup_string(sp, buf, language, id);
1038                 if (len > 0)
1039                         return len;
1040         }
1041
1042         /* String IDs are device-scoped, so we look up each string
1043          * table we're told about.  These lookups are infrequent;
1044          * simpler-is-better here.
1045          */
1046         if (composite->strings) {
1047                 len = lookup_string(composite->strings, buf, language, id);
1048                 if (len > 0)
1049                         return len;
1050         }
1051         list_for_each_entry(c, &cdev->configs, list) {
1052                 if (c->strings) {
1053                         len = lookup_string(c->strings, buf, language, id);
1054                         if (len > 0)
1055                                 return len;
1056                 }
1057                 list_for_each_entry(f, &c->functions, list) {
1058                         if (!f->strings)
1059                                 continue;
1060                         len = lookup_string(f->strings, buf, language, id);
1061                         if (len > 0)
1062                                 return len;
1063                 }
1064         }
1065         return -EINVAL;
1066 }
1067
1068 /**
1069  * usb_string_id() - allocate an unused string ID
1070  * @cdev: the device whose string descriptor IDs are being allocated
1071  * Context: single threaded during gadget setup
1072  *
1073  * @usb_string_id() is called from bind() callbacks to allocate
1074  * string IDs.  Drivers for functions, configurations, or gadgets will
1075  * then store that ID in the appropriate descriptors and string table.
1076  *
1077  * All string identifier should be allocated using this,
1078  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1079  * that for example different functions don't wrongly assign different
1080  * meanings to the same identifier.
1081  */
1082 int usb_string_id(struct usb_composite_dev *cdev)
1083 {
1084         if (cdev->next_string_id < 254) {
1085                 /* string id 0 is reserved by USB spec for list of
1086                  * supported languages */
1087                 /* 255 reserved as well? -- mina86 */
1088                 cdev->next_string_id++;
1089                 return cdev->next_string_id;
1090         }
1091         return -ENODEV;
1092 }
1093 EXPORT_SYMBOL_GPL(usb_string_id);
1094
1095 /**
1096  * usb_string_ids() - allocate unused string IDs in batch
1097  * @cdev: the device whose string descriptor IDs are being allocated
1098  * @str: an array of usb_string objects to assign numbers to
1099  * Context: single threaded during gadget setup
1100  *
1101  * @usb_string_ids() is called from bind() callbacks to allocate
1102  * string IDs.  Drivers for functions, configurations, or gadgets will
1103  * then copy IDs from the string table to the appropriate descriptors
1104  * and string table for other languages.
1105  *
1106  * All string identifier should be allocated using this,
1107  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1108  * example different functions don't wrongly assign different meanings
1109  * to the same identifier.
1110  */
1111 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1112 {
1113         int next = cdev->next_string_id;
1114
1115         for (; str->s; ++str) {
1116                 if (unlikely(next >= 254))
1117                         return -ENODEV;
1118                 str->id = ++next;
1119         }
1120
1121         cdev->next_string_id = next;
1122
1123         return 0;
1124 }
1125 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1126
1127 static struct usb_gadget_string_container *copy_gadget_strings(
1128                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1129                 unsigned n_strings)
1130 {
1131         struct usb_gadget_string_container *uc;
1132         struct usb_gadget_strings **gs_array;
1133         struct usb_gadget_strings *gs;
1134         struct usb_string *s;
1135         unsigned mem;
1136         unsigned n_gs;
1137         unsigned n_s;
1138         void *stash;
1139
1140         mem = sizeof(*uc);
1141         mem += sizeof(void *) * (n_gstrings + 1);
1142         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1143         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1144         uc = kmalloc(mem, GFP_KERNEL);
1145         if (!uc)
1146                 return ERR_PTR(-ENOMEM);
1147         gs_array = get_containers_gs(uc);
1148         stash = uc->stash;
1149         stash += sizeof(void *) * (n_gstrings + 1);
1150         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1151                 struct usb_string *org_s;
1152
1153                 gs_array[n_gs] = stash;
1154                 gs = gs_array[n_gs];
1155                 stash += sizeof(struct usb_gadget_strings);
1156                 gs->language = sp[n_gs]->language;
1157                 gs->strings = stash;
1158                 org_s = sp[n_gs]->strings;
1159
1160                 for (n_s = 0; n_s < n_strings; n_s++) {
1161                         s = stash;
1162                         stash += sizeof(struct usb_string);
1163                         if (org_s->s)
1164                                 s->s = org_s->s;
1165                         else
1166                                 s->s = "";
1167                         org_s++;
1168                 }
1169                 s = stash;
1170                 s->s = NULL;
1171                 stash += sizeof(struct usb_string);
1172
1173         }
1174         gs_array[n_gs] = NULL;
1175         return uc;
1176 }
1177
1178 /**
1179  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1180  * @cdev: the device whose string descriptor IDs are being allocated
1181  * and attached.
1182  * @sp: an array of usb_gadget_strings to attach.
1183  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1184  *
1185  * This function will create a deep copy of usb_gadget_strings and usb_string
1186  * and attach it to the cdev. The actual string (usb_string.s) will not be
1187  * copied but only a referenced will be made. The struct usb_gadget_strings
1188  * array may contain multiple languages and should be NULL terminated.
1189  * The ->language pointer of each struct usb_gadget_strings has to contain the
1190  * same amount of entries.
1191  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1192  * usb_string entry of es-ES contains the translation of the first usb_string
1193  * entry of en-US. Therefore both entries become the same id assign.
1194  */
1195 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1196                 struct usb_gadget_strings **sp, unsigned n_strings)
1197 {
1198         struct usb_gadget_string_container *uc;
1199         struct usb_gadget_strings **n_gs;
1200         unsigned n_gstrings = 0;
1201         unsigned i;
1202         int ret;
1203
1204         for (i = 0; sp[i]; i++)
1205                 n_gstrings++;
1206
1207         if (!n_gstrings)
1208                 return ERR_PTR(-EINVAL);
1209
1210         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1211         if (IS_ERR(uc))
1212                 return ERR_CAST(uc);
1213
1214         n_gs = get_containers_gs(uc);
1215         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1216         if (ret)
1217                 goto err;
1218
1219         for (i = 1; i < n_gstrings; i++) {
1220                 struct usb_string *m_s;
1221                 struct usb_string *s;
1222                 unsigned n;
1223
1224                 m_s = n_gs[0]->strings;
1225                 s = n_gs[i]->strings;
1226                 for (n = 0; n < n_strings; n++) {
1227                         s->id = m_s->id;
1228                         s++;
1229                         m_s++;
1230                 }
1231         }
1232         list_add_tail(&uc->list, &cdev->gstrings);
1233         return n_gs[0]->strings;
1234 err:
1235         kfree(uc);
1236         return ERR_PTR(ret);
1237 }
1238 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1239
1240 /**
1241  * usb_string_ids_n() - allocate unused string IDs in batch
1242  * @c: the device whose string descriptor IDs are being allocated
1243  * @n: number of string IDs to allocate
1244  * Context: single threaded during gadget setup
1245  *
1246  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1247  * valid IDs.  At least provided that @n is non-zero because if it
1248  * is, returns last requested ID which is now very useful information.
1249  *
1250  * @usb_string_ids_n() is called from bind() callbacks to allocate
1251  * string IDs.  Drivers for functions, configurations, or gadgets will
1252  * then store that ID in the appropriate descriptors and string table.
1253  *
1254  * All string identifier should be allocated using this,
1255  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1256  * example different functions don't wrongly assign different meanings
1257  * to the same identifier.
1258  */
1259 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1260 {
1261         unsigned next = c->next_string_id;
1262         if (unlikely(n > 254 || (unsigned)next + n > 254))
1263                 return -ENODEV;
1264         c->next_string_id += n;
1265         return next + 1;
1266 }
1267 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1268
1269 /*-------------------------------------------------------------------------*/
1270
1271 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1272 {
1273         struct usb_composite_dev *cdev;
1274
1275         if (req->status || req->actual != req->length)
1276                 DBG((struct usb_composite_dev *) ep->driver_data,
1277                                 "setup complete --> %d, %d/%d\n",
1278                                 req->status, req->actual, req->length);
1279
1280         /*
1281          * REVIST The same ep0 requests are shared with function drivers
1282          * so they don't have to maintain the same ->complete() stubs.
1283          *
1284          * Because of that, we need to check for the validity of ->context
1285          * here, even though we know we've set it to something useful.
1286          */
1287         if (!req->context)
1288                 return;
1289
1290         cdev = req->context;
1291
1292         if (cdev->req == req)
1293                 cdev->setup_pending = false;
1294         else if (cdev->os_desc_req == req)
1295                 cdev->os_desc_pending = false;
1296         else
1297                 WARN(1, "unknown request %p\n", req);
1298 }
1299
1300 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1301                 struct usb_request *req, gfp_t gfp_flags)
1302 {
1303         int ret;
1304
1305         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1306         if (ret == 0) {
1307                 if (cdev->req == req)
1308                         cdev->setup_pending = true;
1309                 else if (cdev->os_desc_req == req)
1310                         cdev->os_desc_pending = true;
1311                 else
1312                         WARN(1, "unknown request %p\n", req);
1313         }
1314
1315         return ret;
1316 }
1317
1318 static int count_ext_compat(struct usb_configuration *c)
1319 {
1320         int i, res;
1321
1322         res = 0;
1323         for (i = 0; i < c->next_interface_id; ++i) {
1324                 struct usb_function *f;
1325                 int j;
1326
1327                 f = c->interface[i];
1328                 for (j = 0; j < f->os_desc_n; ++j) {
1329                         struct usb_os_desc *d;
1330
1331                         if (i != f->os_desc_table[j].if_id)
1332                                 continue;
1333                         d = f->os_desc_table[j].os_desc;
1334                         if (d && d->ext_compat_id)
1335                                 ++res;
1336                 }
1337         }
1338         BUG_ON(res > 255);
1339         return res;
1340 }
1341
1342 static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1343 {
1344         int i, count;
1345
1346         count = 16;
1347         for (i = 0; i < c->next_interface_id; ++i) {
1348                 struct usb_function *f;
1349                 int j;
1350
1351                 f = c->interface[i];
1352                 for (j = 0; j < f->os_desc_n; ++j) {
1353                         struct usb_os_desc *d;
1354
1355                         if (i != f->os_desc_table[j].if_id)
1356                                 continue;
1357                         d = f->os_desc_table[j].os_desc;
1358                         if (d && d->ext_compat_id) {
1359                                 *buf++ = i;
1360                                 *buf++ = 0x01;
1361                                 memcpy(buf, d->ext_compat_id, 16);
1362                                 buf += 22;
1363                         } else {
1364                                 ++buf;
1365                                 *buf = 0x01;
1366                                 buf += 23;
1367                         }
1368                         count += 24;
1369                         if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1370                                 return count;
1371                 }
1372         }
1373
1374         return count;
1375 }
1376
1377 static int count_ext_prop(struct usb_configuration *c, int interface)
1378 {
1379         struct usb_function *f;
1380         int j;
1381
1382         f = c->interface[interface];
1383         for (j = 0; j < f->os_desc_n; ++j) {
1384                 struct usb_os_desc *d;
1385
1386                 if (interface != f->os_desc_table[j].if_id)
1387                         continue;
1388                 d = f->os_desc_table[j].os_desc;
1389                 if (d && d->ext_compat_id)
1390                         return d->ext_prop_count;
1391         }
1392         return 0;
1393 }
1394
1395 static int len_ext_prop(struct usb_configuration *c, int interface)
1396 {
1397         struct usb_function *f;
1398         struct usb_os_desc *d;
1399         int j, res;
1400
1401         res = 10; /* header length */
1402         f = c->interface[interface];
1403         for (j = 0; j < f->os_desc_n; ++j) {
1404                 if (interface != f->os_desc_table[j].if_id)
1405                         continue;
1406                 d = f->os_desc_table[j].os_desc;
1407                 if (d)
1408                         return min(res + d->ext_prop_len, 4096);
1409         }
1410         return res;
1411 }
1412
1413 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1414 {
1415         struct usb_function *f;
1416         struct usb_os_desc *d;
1417         struct usb_os_desc_ext_prop *ext_prop;
1418         int j, count, n, ret;
1419
1420         f = c->interface[interface];
1421         count = 10; /* header length */
1422         for (j = 0; j < f->os_desc_n; ++j) {
1423                 if (interface != f->os_desc_table[j].if_id)
1424                         continue;
1425                 d = f->os_desc_table[j].os_desc;
1426                 if (d)
1427                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1428                                 n = ext_prop->data_len +
1429                                         ext_prop->name_len + 14;
1430                                 if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1431                                         return count;
1432                                 usb_ext_prop_put_size(buf, n);
1433                                 usb_ext_prop_put_type(buf, ext_prop->type);
1434                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1435                                                             ext_prop->name_len);
1436                                 if (ret < 0)
1437                                         return ret;
1438                                 switch (ext_prop->type) {
1439                                 case USB_EXT_PROP_UNICODE:
1440                                 case USB_EXT_PROP_UNICODE_ENV:
1441                                 case USB_EXT_PROP_UNICODE_LINK:
1442                                         usb_ext_prop_put_unicode(buf, ret,
1443                                                          ext_prop->data,
1444                                                          ext_prop->data_len);
1445                                         break;
1446                                 case USB_EXT_PROP_BINARY:
1447                                         usb_ext_prop_put_binary(buf, ret,
1448                                                         ext_prop->data,
1449                                                         ext_prop->data_len);
1450                                         break;
1451                                 case USB_EXT_PROP_LE32:
1452                                         /* not implemented */
1453                                 case USB_EXT_PROP_BE32:
1454                                         /* not implemented */
1455                                 default:
1456                                         return -EINVAL;
1457                                 }
1458                                 buf += n;
1459                                 count += n;
1460                         }
1461         }
1462
1463         return count;
1464 }
1465
1466 /*
1467  * The setup() callback implements all the ep0 functionality that's
1468  * not handled lower down, in hardware or the hardware driver(like
1469  * device and endpoint feature flags, and their status).  It's all
1470  * housekeeping for the gadget function we're implementing.  Most of
1471  * the work is in config and function specific setup.
1472  */
1473 int
1474 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1475 {
1476         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1477         struct usb_request              *req = cdev->req;
1478         int                             value = -EOPNOTSUPP;
1479         int                             status = 0;
1480         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1481         u8                              intf = w_index & 0xFF;
1482         u16                             w_value = le16_to_cpu(ctrl->wValue);
1483         u16                             w_length = le16_to_cpu(ctrl->wLength);
1484         struct usb_function             *f = NULL;
1485         u8                              endp;
1486
1487         /* partial re-init of the response message; the function or the
1488          * gadget might need to intercept e.g. a control-OUT completion
1489          * when we delegate to it.
1490          */
1491         req->zero = 0;
1492         req->context = cdev;
1493         req->complete = composite_setup_complete;
1494         req->length = 0;
1495         gadget->ep0->driver_data = cdev;
1496
1497         /*
1498          * Don't let non-standard requests match any of the cases below
1499          * by accident.
1500          */
1501         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1502                 goto unknown;
1503
1504         switch (ctrl->bRequest) {
1505
1506         /* we handle all standard USB descriptors */
1507         case USB_REQ_GET_DESCRIPTOR:
1508                 if (ctrl->bRequestType != USB_DIR_IN)
1509                         goto unknown;
1510                 switch (w_value >> 8) {
1511
1512                 case USB_DT_DEVICE:
1513                         cdev->desc.bNumConfigurations =
1514                                 count_configs(cdev, USB_DT_DEVICE);
1515                         cdev->desc.bMaxPacketSize0 =
1516                                 cdev->gadget->ep0->maxpacket;
1517                         if (gadget_is_superspeed(gadget)) {
1518                                 if (gadget->speed >= USB_SPEED_SUPER) {
1519                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1520                                         cdev->desc.bMaxPacketSize0 = 9;
1521                                 } else {
1522                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1523                                 }
1524                         } else {
1525                                 cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1526                         }
1527
1528                         value = min(w_length, (u16) sizeof cdev->desc);
1529                         memcpy(req->buf, &cdev->desc, value);
1530                         break;
1531                 case USB_DT_DEVICE_QUALIFIER:
1532                         if (!gadget_is_dualspeed(gadget) ||
1533                             gadget->speed >= USB_SPEED_SUPER)
1534                                 break;
1535                         device_qual(cdev);
1536                         value = min_t(int, w_length,
1537                                 sizeof(struct usb_qualifier_descriptor));
1538                         break;
1539                 case USB_DT_OTHER_SPEED_CONFIG:
1540                         if (!gadget_is_dualspeed(gadget) ||
1541                             gadget->speed >= USB_SPEED_SUPER)
1542                                 break;
1543                         /* FALLTHROUGH */
1544                 case USB_DT_CONFIG:
1545                         value = config_desc(cdev, w_value);
1546                         if (value >= 0)
1547                                 value = min(w_length, (u16) value);
1548                         break;
1549                 case USB_DT_STRING:
1550                         value = get_string(cdev, req->buf,
1551                                         w_index, w_value & 0xff);
1552                         if (value >= 0)
1553                                 value = min(w_length, (u16) value);
1554                         break;
1555                 case USB_DT_BOS:
1556                         if (gadget_is_superspeed(gadget)) {
1557                                 value = bos_desc(cdev);
1558                                 value = min(w_length, (u16) value);
1559                         }
1560                         break;
1561                 case USB_DT_OTG:
1562                         if (gadget_is_otg(gadget)) {
1563                                 struct usb_configuration *config;
1564                                 int otg_desc_len = 0;
1565
1566                                 if (cdev->config)
1567                                         config = cdev->config;
1568                                 else
1569                                         config = list_first_entry(
1570                                                         &cdev->configs,
1571                                                 struct usb_configuration, list);
1572                                 if (!config)
1573                                         goto done;
1574
1575                                 if (gadget->otg_caps &&
1576                                         (gadget->otg_caps->otg_rev >= 0x0200))
1577                                         otg_desc_len += sizeof(
1578                                                 struct usb_otg20_descriptor);
1579                                 else
1580                                         otg_desc_len += sizeof(
1581                                                 struct usb_otg_descriptor);
1582
1583                                 value = min_t(int, w_length, otg_desc_len);
1584                                 memcpy(req->buf, config->descriptors[0], value);
1585                         }
1586                         break;
1587                 }
1588                 break;
1589
1590         /* any number of configs can work */
1591         case USB_REQ_SET_CONFIGURATION:
1592                 if (ctrl->bRequestType != 0)
1593                         goto unknown;
1594                 if (gadget_is_otg(gadget)) {
1595                         if (gadget->a_hnp_support)
1596                                 DBG(cdev, "HNP available\n");
1597                         else if (gadget->a_alt_hnp_support)
1598                                 DBG(cdev, "HNP on another port\n");
1599                         else
1600                                 VDBG(cdev, "HNP inactive\n");
1601                 }
1602                 spin_lock(&cdev->lock);
1603                 value = set_config(cdev, ctrl, w_value);
1604                 spin_unlock(&cdev->lock);
1605                 break;
1606         case USB_REQ_GET_CONFIGURATION:
1607                 if (ctrl->bRequestType != USB_DIR_IN)
1608                         goto unknown;
1609                 if (cdev->config)
1610                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1611                 else
1612                         *(u8 *)req->buf = 0;
1613                 value = min(w_length, (u16) 1);
1614                 break;
1615
1616         /* function drivers must handle get/set altsetting */
1617         case USB_REQ_SET_INTERFACE:
1618                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1619                         goto unknown;
1620                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1621                         break;
1622                 f = cdev->config->interface[intf];
1623                 if (!f)
1624                         break;
1625
1626                 /*
1627                  * If there's no get_alt() method, we know only altsetting zero
1628                  * works. There is no need to check if set_alt() is not NULL
1629                  * as we check this in usb_add_function().
1630                  */
1631                 if (w_value && !f->get_alt)
1632                         break;
1633
1634                 spin_lock(&cdev->lock);
1635                 value = f->set_alt(f, w_index, w_value);
1636                 if (value == USB_GADGET_DELAYED_STATUS) {
1637                         DBG(cdev,
1638                          "%s: interface %d (%s) requested delayed status\n",
1639                                         __func__, intf, f->name);
1640                         cdev->delayed_status++;
1641                         DBG(cdev, "delayed_status count %d\n",
1642                                         cdev->delayed_status);
1643                 }
1644                 spin_unlock(&cdev->lock);
1645                 break;
1646         case USB_REQ_GET_INTERFACE:
1647                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1648                         goto unknown;
1649                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1650                         break;
1651                 f = cdev->config->interface[intf];
1652                 if (!f)
1653                         break;
1654                 /* lots of interfaces only need altsetting zero... */
1655                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1656                 if (value < 0)
1657                         break;
1658                 *((u8 *)req->buf) = value;
1659                 value = min(w_length, (u16) 1);
1660                 break;
1661
1662         /*
1663          * USB 3.0 additions:
1664          * Function driver should handle get_status request. If such cb
1665          * wasn't supplied we respond with default value = 0
1666          * Note: function driver should supply such cb only for the first
1667          * interface of the function
1668          */
1669         case USB_REQ_GET_STATUS:
1670                 if (!gadget_is_superspeed(gadget))
1671                         goto unknown;
1672                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1673                         goto unknown;
1674                 value = 2;      /* This is the length of the get_status reply */
1675                 put_unaligned_le16(0, req->buf);
1676                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1677                         break;
1678                 f = cdev->config->interface[intf];
1679                 if (!f)
1680                         break;
1681                 status = f->get_status ? f->get_status(f) : 0;
1682                 if (status < 0)
1683                         break;
1684                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1685                 break;
1686         /*
1687          * Function drivers should handle SetFeature/ClearFeature
1688          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1689          * only for the first interface of the function
1690          */
1691         case USB_REQ_CLEAR_FEATURE:
1692         case USB_REQ_SET_FEATURE:
1693                 if (!gadget_is_superspeed(gadget))
1694                         goto unknown;
1695                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1696                         goto unknown;
1697                 switch (w_value) {
1698                 case USB_INTRF_FUNC_SUSPEND:
1699                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1700                                 break;
1701                         f = cdev->config->interface[intf];
1702                         if (!f)
1703                                 break;
1704                         value = 0;
1705                         if (f->func_suspend)
1706                                 value = f->func_suspend(f, w_index >> 8);
1707                         if (value < 0) {
1708                                 ERROR(cdev,
1709                                       "func_suspend() returned error %d\n",
1710                                       value);
1711                                 value = 0;
1712                         }
1713                         break;
1714                 }
1715                 break;
1716         default:
1717 unknown:
1718                 /*
1719                  * OS descriptors handling
1720                  */
1721                 if (cdev->use_os_string && cdev->os_desc_config &&
1722                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1723                     ctrl->bRequest == cdev->b_vendor_code) {
1724                         struct usb_request              *req;
1725                         struct usb_configuration        *os_desc_cfg;
1726                         u8                              *buf;
1727                         int                             interface;
1728                         int                             count = 0;
1729
1730                         req = cdev->os_desc_req;
1731                         req->context = cdev;
1732                         req->complete = composite_setup_complete;
1733                         buf = req->buf;
1734                         os_desc_cfg = cdev->os_desc_config;
1735                         w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1736                         memset(buf, 0, w_length);
1737                         buf[5] = 0x01;
1738                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1739                         case USB_RECIP_DEVICE:
1740                                 if (w_index != 0x4 || (w_value >> 8))
1741                                         break;
1742                                 buf[6] = w_index;
1743                                 if (w_length == 0x10) {
1744                                         /* Number of ext compat interfaces */
1745                                         count = count_ext_compat(os_desc_cfg);
1746                                         buf[8] = count;
1747                                         count *= 24; /* 24 B/ext compat desc */
1748                                         count += 16; /* header */
1749                                         put_unaligned_le32(count, buf);
1750                                         value = w_length;
1751                                 } else {
1752                                         /* "extended compatibility ID"s */
1753                                         count = count_ext_compat(os_desc_cfg);
1754                                         buf[8] = count;
1755                                         count *= 24; /* 24 B/ext compat desc */
1756                                         count += 16; /* header */
1757                                         put_unaligned_le32(count, buf);
1758                                         buf += 16;
1759                                         value = fill_ext_compat(os_desc_cfg, buf);
1760                                         value = min_t(u16, w_length, value);
1761                                 }
1762                                 break;
1763                         case USB_RECIP_INTERFACE:
1764                                 if (w_index != 0x5 || (w_value >> 8))
1765                                         break;
1766                                 interface = w_value & 0xFF;
1767                                 buf[6] = w_index;
1768                                 if (w_length == 0x0A) {
1769                                         count = count_ext_prop(os_desc_cfg,
1770                                                 interface);
1771                                         put_unaligned_le16(count, buf + 8);
1772                                         count = len_ext_prop(os_desc_cfg,
1773                                                 interface);
1774                                         put_unaligned_le32(count, buf);
1775
1776                                         value = w_length;
1777                                 } else {
1778                                         count = count_ext_prop(os_desc_cfg,
1779                                                 interface);
1780                                         put_unaligned_le16(count, buf + 8);
1781                                         count = len_ext_prop(os_desc_cfg,
1782                                                 interface);
1783                                         put_unaligned_le32(count, buf);
1784                                         buf += 10;
1785                                         value = fill_ext_prop(os_desc_cfg,
1786                                                               interface, buf);
1787                                         if (value < 0)
1788                                                 return value;
1789                                         value = min_t(u16, w_length, value);
1790                                 }
1791                                 break;
1792                         }
1793                         req->length = value;
1794                         req->context = cdev;
1795                         req->zero = value < w_length;
1796                         value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1797                         if (value < 0) {
1798                                 DBG(cdev, "ep_queue --> %d\n", value);
1799                                 req->status = 0;
1800                                 composite_setup_complete(gadget->ep0, req);
1801                         }
1802                         return value;
1803                 }
1804
1805                 VDBG(cdev,
1806                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1807                         ctrl->bRequestType, ctrl->bRequest,
1808                         w_value, w_index, w_length);
1809
1810                 /* functions always handle their interfaces and endpoints...
1811                  * punt other recipients (other, WUSB, ...) to the current
1812                  * configuration code.
1813                  *
1814                  * REVISIT it could make sense to let the composite device
1815                  * take such requests too, if that's ever needed:  to work
1816                  * in config 0, etc.
1817                  */
1818                 if (cdev->config) {
1819                         list_for_each_entry(f, &cdev->config->functions, list)
1820                                 if (f->req_match && f->req_match(f, ctrl))
1821                                         goto try_fun_setup;
1822                         f = NULL;
1823                 }
1824
1825                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1826                 case USB_RECIP_INTERFACE:
1827                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1828                                 break;
1829                         f = cdev->config->interface[intf];
1830                         break;
1831
1832                 case USB_RECIP_ENDPOINT:
1833                         if (!cdev->config)
1834                                 break;
1835                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1836                         list_for_each_entry(f, &cdev->config->functions, list) {
1837                                 if (test_bit(endp, f->endpoints))
1838                                         break;
1839                         }
1840                         if (&f->list == &cdev->config->functions)
1841                                 f = NULL;
1842                         break;
1843                 }
1844 try_fun_setup:
1845                 if (f && f->setup)
1846                         value = f->setup(f, ctrl);
1847                 else {
1848                         struct usb_configuration        *c;
1849
1850                         c = cdev->config;
1851                         if (!c)
1852                                 goto done;
1853
1854                         /* try current config's setup */
1855                         if (c->setup) {
1856                                 value = c->setup(c, ctrl);
1857                                 goto done;
1858                         }
1859
1860                         /* try the only function in the current config */
1861                         if (!list_is_singular(&c->functions))
1862                                 goto done;
1863                         f = list_first_entry(&c->functions, struct usb_function,
1864                                              list);
1865                         if (f->setup)
1866                                 value = f->setup(f, ctrl);
1867                 }
1868
1869                 goto done;
1870         }
1871
1872         /* respond with data transfer before status phase? */
1873         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1874                 req->length = value;
1875                 req->context = cdev;
1876                 req->zero = value < w_length;
1877                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1878                 if (value < 0) {
1879                         DBG(cdev, "ep_queue --> %d\n", value);
1880                         req->status = 0;
1881                         composite_setup_complete(gadget->ep0, req);
1882                 }
1883         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1884                 WARN(cdev,
1885                         "%s: Delayed status not supported for w_length != 0",
1886                         __func__);
1887         }
1888
1889 done:
1890         /* device either stalls (value < 0) or reports success */
1891         return value;
1892 }
1893
1894 void composite_disconnect(struct usb_gadget *gadget)
1895 {
1896         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1897         unsigned long                   flags;
1898
1899         /* REVISIT:  should we have config and device level
1900          * disconnect callbacks?
1901          */
1902         spin_lock_irqsave(&cdev->lock, flags);
1903         cdev->suspended = 0;
1904         if (cdev->config)
1905                 reset_config(cdev);
1906         if (cdev->driver->disconnect)
1907                 cdev->driver->disconnect(cdev);
1908         spin_unlock_irqrestore(&cdev->lock, flags);
1909 }
1910
1911 /*-------------------------------------------------------------------------*/
1912
1913 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
1914                               char *buf)
1915 {
1916         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1917         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1918
1919         return sprintf(buf, "%d\n", cdev->suspended);
1920 }
1921 static DEVICE_ATTR_RO(suspended);
1922
1923 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1924 {
1925         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1926         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
1927         struct usb_string               *dev_str = gstr->strings;
1928
1929         /* composite_disconnect() must already have been called
1930          * by the underlying peripheral controller driver!
1931          * so there's no i/o concurrency that could affect the
1932          * state protected by cdev->lock.
1933          */
1934         WARN_ON(cdev->config);
1935
1936         while (!list_empty(&cdev->configs)) {
1937                 struct usb_configuration        *c;
1938                 c = list_first_entry(&cdev->configs,
1939                                 struct usb_configuration, list);
1940                 remove_config(cdev, c);
1941         }
1942         if (cdev->driver->unbind && unbind_driver)
1943                 cdev->driver->unbind(cdev);
1944
1945         composite_dev_cleanup(cdev);
1946
1947         if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
1948                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
1949
1950         kfree(cdev->def_manufacturer);
1951         kfree(cdev);
1952         set_gadget_data(gadget, NULL);
1953 }
1954
1955 static void composite_unbind(struct usb_gadget *gadget)
1956 {
1957         __composite_unbind(gadget, true);
1958 }
1959
1960 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1961                 const struct usb_device_descriptor *old)
1962 {
1963         __le16 idVendor;
1964         __le16 idProduct;
1965         __le16 bcdDevice;
1966         u8 iSerialNumber;
1967         u8 iManufacturer;
1968         u8 iProduct;
1969
1970         /*
1971          * these variables may have been set in
1972          * usb_composite_overwrite_options()
1973          */
1974         idVendor = new->idVendor;
1975         idProduct = new->idProduct;
1976         bcdDevice = new->bcdDevice;
1977         iSerialNumber = new->iSerialNumber;
1978         iManufacturer = new->iManufacturer;
1979         iProduct = new->iProduct;
1980
1981         *new = *old;
1982         if (idVendor)
1983                 new->idVendor = idVendor;
1984         if (idProduct)
1985                 new->idProduct = idProduct;
1986         if (bcdDevice)
1987                 new->bcdDevice = bcdDevice;
1988         else
1989                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1990         if (iSerialNumber)
1991                 new->iSerialNumber = iSerialNumber;
1992         if (iManufacturer)
1993                 new->iManufacturer = iManufacturer;
1994         if (iProduct)
1995                 new->iProduct = iProduct;
1996 }
1997
1998 int composite_dev_prepare(struct usb_composite_driver *composite,
1999                 struct usb_composite_dev *cdev)
2000 {
2001         struct usb_gadget *gadget = cdev->gadget;
2002         int ret = -ENOMEM;
2003
2004         /* preallocate control response and buffer */
2005         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2006         if (!cdev->req)
2007                 return -ENOMEM;
2008
2009         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2010         if (!cdev->req->buf)
2011                 goto fail;
2012
2013         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2014         if (ret)
2015                 goto fail_dev;
2016
2017         cdev->req->complete = composite_setup_complete;
2018         cdev->req->context = cdev;
2019         gadget->ep0->driver_data = cdev;
2020
2021         cdev->driver = composite;
2022
2023         /*
2024          * As per USB compliance update, a device that is actively drawing
2025          * more than 100mA from USB must report itself as bus-powered in
2026          * the GetStatus(DEVICE) call.
2027          */
2028         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2029                 usb_gadget_set_selfpowered(gadget);
2030
2031         /* interface and string IDs start at zero via kzalloc.
2032          * we force endpoints to start unassigned; few controller
2033          * drivers will zero ep->driver_data.
2034          */
2035         usb_ep_autoconfig_reset(gadget);
2036         return 0;
2037 fail_dev:
2038         kfree(cdev->req->buf);
2039 fail:
2040         usb_ep_free_request(gadget->ep0, cdev->req);
2041         cdev->req = NULL;
2042         return ret;
2043 }
2044
2045 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2046                                   struct usb_ep *ep0)
2047 {
2048         int ret = 0;
2049
2050         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2051         if (!cdev->os_desc_req) {
2052                 ret = PTR_ERR(cdev->os_desc_req);
2053                 goto end;
2054         }
2055
2056         cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2057                                          GFP_KERNEL);
2058         if (!cdev->os_desc_req->buf) {
2059                 ret = PTR_ERR(cdev->os_desc_req->buf);
2060                 kfree(cdev->os_desc_req);
2061                 goto end;
2062         }
2063         cdev->os_desc_req->context = cdev;
2064         cdev->os_desc_req->complete = composite_setup_complete;
2065 end:
2066         return ret;
2067 }
2068
2069 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2070 {
2071         struct usb_gadget_string_container *uc, *tmp;
2072
2073         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2074                 list_del(&uc->list);
2075                 kfree(uc);
2076         }
2077         if (cdev->os_desc_req) {
2078                 if (cdev->os_desc_pending)
2079                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2080
2081                 kfree(cdev->os_desc_req->buf);
2082                 cdev->os_desc_req->buf = NULL;
2083                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2084                 cdev->os_desc_req = NULL;
2085         }
2086         if (cdev->req) {
2087                 if (cdev->setup_pending)
2088                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2089
2090                 kfree(cdev->req->buf);
2091                 cdev->req->buf = NULL;
2092                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2093                 cdev->req = NULL;
2094         }
2095         cdev->next_string_id = 0;
2096         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2097 }
2098
2099 static int composite_bind(struct usb_gadget *gadget,
2100                 struct usb_gadget_driver *gdriver)
2101 {
2102         struct usb_composite_dev        *cdev;
2103         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2104         int                             status = -ENOMEM;
2105
2106         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2107         if (!cdev)
2108                 return status;
2109
2110         spin_lock_init(&cdev->lock);
2111         cdev->gadget = gadget;
2112         set_gadget_data(gadget, cdev);
2113         INIT_LIST_HEAD(&cdev->configs);
2114         INIT_LIST_HEAD(&cdev->gstrings);
2115
2116         status = composite_dev_prepare(composite, cdev);
2117         if (status)
2118                 goto fail;
2119
2120         /* composite gadget needs to assign strings for whole device (like
2121          * serial number), register function drivers, potentially update
2122          * power state and consumption, etc
2123          */
2124         status = composite->bind(cdev);
2125         if (status < 0)
2126                 goto fail;
2127
2128         if (cdev->use_os_string) {
2129                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2130                 if (status)
2131                         goto fail;
2132         }
2133
2134         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2135
2136         /* has userspace failed to provide a serial number? */
2137         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2138                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2139
2140         INFO(cdev, "%s ready\n", composite->name);
2141         return 0;
2142
2143 fail:
2144         __composite_unbind(gadget, false);
2145         return status;
2146 }
2147
2148 /*-------------------------------------------------------------------------*/
2149
2150 void composite_suspend(struct usb_gadget *gadget)
2151 {
2152         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2153         struct usb_function             *f;
2154
2155         /* REVISIT:  should we have config level
2156          * suspend/resume callbacks?
2157          */
2158         DBG(cdev, "suspend\n");
2159         if (cdev->config) {
2160                 list_for_each_entry(f, &cdev->config->functions, list) {
2161                         if (f->suspend)
2162                                 f->suspend(f);
2163                 }
2164         }
2165         if (cdev->driver->suspend)
2166                 cdev->driver->suspend(cdev);
2167
2168         cdev->suspended = 1;
2169
2170         usb_gadget_set_selfpowered(gadget);
2171         usb_gadget_vbus_draw(gadget, 2);
2172 }
2173
2174 void composite_resume(struct usb_gadget *gadget)
2175 {
2176         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2177         struct usb_function             *f;
2178         u16                             maxpower;
2179
2180         /* REVISIT:  should we have config level
2181          * suspend/resume callbacks?
2182          */
2183         DBG(cdev, "resume\n");
2184         if (cdev->driver->resume)
2185                 cdev->driver->resume(cdev);
2186         if (cdev->config) {
2187                 list_for_each_entry(f, &cdev->config->functions, list) {
2188                         if (f->resume)
2189                                 f->resume(f);
2190                 }
2191
2192                 maxpower = cdev->config->MaxPower;
2193
2194                 if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2195                         usb_gadget_clear_selfpowered(gadget);
2196
2197                 usb_gadget_vbus_draw(gadget, maxpower ?
2198                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
2199         }
2200
2201         cdev->suspended = 0;
2202 }
2203
2204 /*-------------------------------------------------------------------------*/
2205
2206 static const struct usb_gadget_driver composite_driver_template = {
2207         .bind           = composite_bind,
2208         .unbind         = composite_unbind,
2209
2210         .setup          = composite_setup,
2211         .reset          = composite_disconnect,
2212         .disconnect     = composite_disconnect,
2213
2214         .suspend        = composite_suspend,
2215         .resume         = composite_resume,
2216
2217         .driver = {
2218                 .owner          = THIS_MODULE,
2219         },
2220 };
2221
2222 /**
2223  * usb_composite_probe() - register a composite driver
2224  * @driver: the driver to register
2225  *
2226  * Context: single threaded during gadget setup
2227  *
2228  * This function is used to register drivers using the composite driver
2229  * framework.  The return value is zero, or a negative errno value.
2230  * Those values normally come from the driver's @bind method, which does
2231  * all the work of setting up the driver to match the hardware.
2232  *
2233  * On successful return, the gadget is ready to respond to requests from
2234  * the host, unless one of its components invokes usb_gadget_disconnect()
2235  * while it was binding.  That would usually be done in order to wait for
2236  * some userspace participation.
2237  */
2238 int usb_composite_probe(struct usb_composite_driver *driver)
2239 {
2240         struct usb_gadget_driver *gadget_driver;
2241
2242         if (!driver || !driver->dev || !driver->bind)
2243                 return -EINVAL;
2244
2245         if (!driver->name)
2246                 driver->name = "composite";
2247
2248         driver->gadget_driver = composite_driver_template;
2249         gadget_driver = &driver->gadget_driver;
2250
2251         gadget_driver->function =  (char *) driver->name;
2252         gadget_driver->driver.name = driver->name;
2253         gadget_driver->max_speed = driver->max_speed;
2254
2255         return usb_gadget_probe_driver(gadget_driver);
2256 }
2257 EXPORT_SYMBOL_GPL(usb_composite_probe);
2258
2259 /**
2260  * usb_composite_unregister() - unregister a composite driver
2261  * @driver: the driver to unregister
2262  *
2263  * This function is used to unregister drivers using the composite
2264  * driver framework.
2265  */
2266 void usb_composite_unregister(struct usb_composite_driver *driver)
2267 {
2268         usb_gadget_unregister_driver(&driver->gadget_driver);
2269 }
2270 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2271
2272 /**
2273  * usb_composite_setup_continue() - Continue with the control transfer
2274  * @cdev: the composite device who's control transfer was kept waiting
2275  *
2276  * This function must be called by the USB function driver to continue
2277  * with the control transfer's data/status stage in case it had requested to
2278  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2279  * can request the composite framework to delay the setup request's data/status
2280  * stages by returning USB_GADGET_DELAYED_STATUS.
2281  */
2282 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2283 {
2284         int                     value;
2285         struct usb_request      *req = cdev->req;
2286         unsigned long           flags;
2287
2288         DBG(cdev, "%s\n", __func__);
2289         spin_lock_irqsave(&cdev->lock, flags);
2290
2291         if (cdev->delayed_status == 0) {
2292                 WARN(cdev, "%s: Unexpected call\n", __func__);
2293
2294         } else if (--cdev->delayed_status == 0) {
2295                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2296                 req->length = 0;
2297                 req->context = cdev;
2298                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2299                 if (value < 0) {
2300                         DBG(cdev, "ep_queue --> %d\n", value);
2301                         req->status = 0;
2302                         composite_setup_complete(cdev->gadget->ep0, req);
2303                 }
2304         }
2305
2306         spin_unlock_irqrestore(&cdev->lock, flags);
2307 }
2308 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2309
2310 static char *composite_default_mfr(struct usb_gadget *gadget)
2311 {
2312         char *mfr;
2313         int len;
2314
2315         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
2316                         init_utsname()->release, gadget->name);
2317         len++;
2318         mfr = kmalloc(len, GFP_KERNEL);
2319         if (!mfr)
2320                 return NULL;
2321         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
2322                         init_utsname()->release, gadget->name);
2323         return mfr;
2324 }
2325
2326 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2327                 struct usb_composite_overwrite *covr)
2328 {
2329         struct usb_device_descriptor    *desc = &cdev->desc;
2330         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2331         struct usb_string               *dev_str = gstr->strings;
2332
2333         if (covr->idVendor)
2334                 desc->idVendor = cpu_to_le16(covr->idVendor);
2335
2336         if (covr->idProduct)
2337                 desc->idProduct = cpu_to_le16(covr->idProduct);
2338
2339         if (covr->bcdDevice)
2340                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2341
2342         if (covr->serial_number) {
2343                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2344                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2345         }
2346         if (covr->manufacturer) {
2347                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2348                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2349
2350         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2351                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2352                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2353                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2354         }
2355
2356         if (covr->product) {
2357                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2358                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2359         }
2360 }
2361 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2362
2363 MODULE_LICENSE("GPL");
2364 MODULE_AUTHOR("David Brownell");