drivers/usb/gadget/composite.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * composite.c - infrastructure for Composite USB Gadgets
   4  *
   5  * Copyright (C) 2006-2008 David Brownell
   6  */
   7
   8 /* #define VERBOSE_DEBUG */
   9
  10 #include <linux/kallsyms.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14 #include <linux/device.h>
  15 #include <linux/utsname.h>
  16 #include <linux/bitfield.h>
  17
  18 #include <linux/usb/composite.h>
  19 #include <linux/usb/otg.h>
  20 #include <asm/unaligned.h>
  21
  22 #include "u_os_desc.h"
  23
  24 /**
  25  * struct usb_os_string - represents OS String to be reported by a gadget
  26  * @bLength: total length of the entire descritor, always 0x12
  27  * @bDescriptorType: USB_DT_STRING
  28  * @qwSignature: the OS String proper
  29  * @bMS_VendorCode: code used by the host for subsequent requests
  30  * @bPad: not used, must be zero
  31  */
  32 struct usb_os_string {
  33         __u8    bLength;
  34         __u8    bDescriptorType;
  35         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  36         __u8    bMS_VendorCode;
  37         __u8    bPad;
  38 } __packed;
  39
  40 /*
  41  * The code in this file is utility code, used to build a gadget driver
  42  * from one or more "function" drivers, one or more "configuration"
  43  * objects, and a "usb_composite_driver" by gluing them together along
  44  * with the relevant device-wide data.
  45  */
  46
  47 static struct usb_gadget_strings **get_containers_gs(
  48                 struct usb_gadget_string_container *uc)
  49 {
  50         return (struct usb_gadget_strings **)uc->stash;
  51 }
  52
  53 /**
  54  * function_descriptors() - get function descriptors for speed
  55  * @f: the function
  56  * @speed: the speed
  57  *
  58  * Returns the descriptors or NULL if not set.
  59  */
  60 static struct usb_descriptor_header **
  61 function_descriptors(struct usb_function *f,
  62                      enum usb_device_speed speed)
  63 {
  64         struct usb_descriptor_header **descriptors;
  65
  66         /*
  67          * NOTE: we try to help gadget drivers which might not be setting
  68          * max_speed appropriately.
  69          */
  70
  71         switch (speed) {
  72         case USB_SPEED_SUPER_PLUS:
  73                 descriptors = f->ssp_descriptors;
  74                 if (descriptors)
  75                         break;
  76                 fallthrough;
  77         case USB_SPEED_SUPER:
  78                 descriptors = f->ss_descriptors;
  79                 if (descriptors)
  80                         break;
  81                 fallthrough;
  82         case USB_SPEED_HIGH:
  83                 descriptors = f->hs_descriptors;
  84                 if (descriptors)
  85                         break;
  86                 fallthrough;
  87         default:
  88                 descriptors = f->fs_descriptors;
  89         }
  90
  91         /*
  92          * if we can't find any descriptors at all, then this gadget deserves to
  93          * Oops with a NULL pointer dereference
  94          */
  95
  96         return descriptors;
  97 }
  98
  99 /**
 100  * next_desc() - advance to the next desc_type descriptor
 101  * @t: currect pointer within descriptor array
 102  * @desc_type: descriptor type
 103  *
 104  * Return: next desc_type descriptor or NULL
 105  *
 106  * Iterate over @t until either desc_type descriptor found or
 107  * NULL (that indicates end of list) encountered
 108  */
 109 static struct usb_descriptor_header**
 110 next_desc(struct usb_descriptor_header **t, u8 desc_type)
 111 {
 112         for (; *t; t++) {
 113                 if ((*t)->bDescriptorType == desc_type)
 114                         return t;
 115         }
 116         return NULL;
 117 }
 118
 119 /*
 120  * for_each_desc() - iterate over desc_type descriptors in the
 121  * descriptors list
 122  * @start: pointer within descriptor array.
 123  * @iter_desc: desc_type descriptor to use as the loop cursor
 124  * @desc_type: wanted descriptr type
 125  */
 126 #define for_each_desc(start, iter_desc, desc_type) \
 127         for (iter_desc = next_desc(start, desc_type); \
 128              iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
 129
 130 /**
 131  * config_ep_by_speed_and_alt() - configures the given endpoint
 132  * according to gadget speed.
 133  * @g: pointer to the gadget
 134  * @f: usb function
 135  * @_ep: the endpoint to configure
 136  * @alt: alternate setting number
 137  *
 138  * Return: error code, 0 on success
 139  *
 140  * This function chooses the right descriptors for a given
 141  * endpoint according to gadget speed and saves it in the
 142  * endpoint desc field. If the endpoint already has a descriptor
 143  * assigned to it - overwrites it with currently corresponding
 144  * descriptor. The endpoint maxpacket field is updated according
 145  * to the chosen descriptor.
 146  * Note: the supplied function should hold all the descriptors
 147  * for supported speeds
 148  */
 149 int config_ep_by_speed_and_alt(struct usb_gadget *g,
 150                                 struct usb_function *f,
 151                                 struct usb_ep *_ep,
 152                                 u8 alt)
 153 {
 154         struct usb_endpoint_descriptor *chosen_desc = NULL;
 155         struct usb_interface_descriptor *int_desc = NULL;
 156         struct usb_descriptor_header **speed_desc = NULL;
 157
 158         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 159         int want_comp_desc = 0;
 160
 161         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 162         struct usb_composite_dev *cdev;
 163         bool incomplete_desc = false;
 164
 165         if (!g || !f || !_ep)
 166                 return -EIO;
 167
 168         /* select desired speed */
 169         switch (g->speed) {
 170         case USB_SPEED_SUPER_PLUS:
 171                 if (gadget_is_superspeed_plus(g)) {
 172                         if (f->ssp_descriptors) {
 173                                 speed_desc = f->ssp_descriptors;
 174                                 want_comp_desc = 1;
 175                                 break;
 176                         }
 177                         incomplete_desc = true;
 178                 }
 179                 fallthrough;
 180         case USB_SPEED_SUPER:
 181                 if (gadget_is_superspeed(g)) {
 182                         if (f->ss_descriptors) {
 183                                 speed_desc = f->ss_descriptors;
 184                                 want_comp_desc = 1;
 185                                 break;
 186                         }
 187                         incomplete_desc = true;
 188                 }
 189                 fallthrough;
 190         case USB_SPEED_HIGH:
 191                 if (gadget_is_dualspeed(g)) {
 192                         if (f->hs_descriptors) {
 193                                 speed_desc = f->hs_descriptors;
 194                                 break;
 195                         }
 196                         incomplete_desc = true;
 197                 }
 198                 fallthrough;
 199         default:
 200                 speed_desc = f->fs_descriptors;
 201         }
 202
 203         cdev = get_gadget_data(g);
 204         if (incomplete_desc)
 205                 WARNING(cdev,
 206                         "%s doesn't hold the descriptors for current speed\n",
 207                         f->name);
 208
 209         /* find correct alternate setting descriptor */
 210         for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
 211                 int_desc = (struct usb_interface_descriptor *)*d_spd;
 212
 213                 if (int_desc->bAlternateSetting == alt) {
 214                         speed_desc = d_spd;
 215                         goto intf_found;
 216                 }
 217         }
 218         return -EIO;
 219
 220 intf_found:
 221         /* find descriptors */
 222         for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
 223                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 224                 if (chosen_desc->bEndpointAddress == _ep->address)
 225                         goto ep_found;
 226         }
 227         return -EIO;
 228
 229 ep_found:
 230         /* commit results */
 231         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 232         _ep->desc = chosen_desc;
 233         _ep->comp_desc = NULL;
 234         _ep->maxburst = 0;
 235         _ep->mult = 1;
 236
 237         if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 238                                 usb_endpoint_xfer_int(_ep->desc)))
 239                 _ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 240
 241         if (!want_comp_desc)
 242                 return 0;
 243
 244         /*
 245          * Companion descriptor should follow EP descriptor
 246          * USB 3.0 spec, #9.6.7
 247          */
 248         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 249         if (!comp_desc ||
 250             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 251                 return -EIO;
 252         _ep->comp_desc = comp_desc;
 253         if (g->speed >= USB_SPEED_SUPER) {
 254                 switch (usb_endpoint_type(_ep->desc)) {
 255                 case USB_ENDPOINT_XFER_ISOC:
 256                         /* mult: bits 1:0 of bmAttributes */
 257                         _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 258                         fallthrough;
 259                 case USB_ENDPOINT_XFER_BULK:
 260                 case USB_ENDPOINT_XFER_INT:
 261                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 262                         break;
 263                 default:
 264                         if (comp_desc->bMaxBurst != 0)
 265                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 266                         _ep->maxburst = 1;
 267                         break;
 268                 }
 269         }
 270         return 0;
 271 }
 272 EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
 273
 274 /**
 275  * config_ep_by_speed() - configures the given endpoint
 276  * according to gadget speed.
 277  * @g: pointer to the gadget
 278  * @f: usb function
 279  * @_ep: the endpoint to configure
 280  *
 281  * Return: error code, 0 on success
 282  *
 283  * This function chooses the right descriptors for a given
 284  * endpoint according to gadget speed and saves it in the
 285  * endpoint desc field. If the endpoint already has a descriptor
 286  * assigned to it - overwrites it with currently corresponding
 287  * descriptor. The endpoint maxpacket field is updated according
 288  * to the chosen descriptor.
 289  * Note: the supplied function should hold all the descriptors
 290  * for supported speeds
 291  */
 292 int config_ep_by_speed(struct usb_gadget *g,
 293                         struct usb_function *f,
 294                         struct usb_ep *_ep)
 295 {
 296         return config_ep_by_speed_and_alt(g, f, _ep, 0);
 297 }
 298 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 299
 300 /**
 301  * usb_add_function() - add a function to a configuration
 302  * @config: the configuration
 303  * @function: the function being added
 304  * Context: single threaded during gadget setup
 305  *
 306  * After initialization, each configuration must have one or more
 307  * functions added to it.  Adding a function involves calling its @bind()
 308  * method to allocate resources such as interface and string identifiers
 309  * and endpoints.
 310  *
 311  * This function returns the value of the function's bind(), which is
 312  * zero for success else a negative errno value.
 313  */
 314 int usb_add_function(struct usb_configuration *config,
 315                 struct usb_function *function)
 316 {
 317         int     value = -EINVAL;
 318
 319         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 320                         function->name, function,
 321                         config->label, config);
 322
 323         if (!function->set_alt || !function->disable)
 324                 goto done;
 325
 326         function->config = config;
 327         list_add_tail(&function->list, &config->functions);
 328
 329         if (function->bind_deactivated) {
 330                 value = usb_function_deactivate(function);
 331                 if (value)
 332                         goto done;
 333         }
 334
 335         /* REVISIT *require* function->bind? */
 336         if (function->bind) {
 337                 value = function->bind(config, function);
 338                 if (value < 0) {
 339                         list_del(&function->list);
 340                         function->config = NULL;
 341                 }
 342         } else
 343                 value = 0;
 344
 345         /* We allow configurations that don't work at both speeds.
 346          * If we run into a lowspeed Linux system, treat it the same
 347          * as full speed ... it's the function drivers that will need
 348          * to avoid bulk and ISO transfers.
 349          */
 350         if (!config->fullspeed && function->fs_descriptors)
 351                 config->fullspeed = true;
 352         if (!config->highspeed && function->hs_descriptors)
 353                 config->highspeed = true;
 354         if (!config->superspeed && function->ss_descriptors)
 355                 config->superspeed = true;
 356         if (!config->superspeed_plus && function->ssp_descriptors)
 357                 config->superspeed_plus = true;
 358
 359 done:
 360         if (value)
 361                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 362                                 function->name, function, value);
 363         return value;
 364 }
 365 EXPORT_SYMBOL_GPL(usb_add_function);
 366
 367 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 368 {
 369         if (f->disable)
 370                 f->disable(f);
 371
 372         bitmap_zero(f->endpoints, 32);
 373         list_del(&f->list);
 374         if (f->unbind)
 375                 f->unbind(c, f);
 376
 377         if (f->bind_deactivated)
 378                 usb_function_activate(f);
 379 }
 380 EXPORT_SYMBOL_GPL(usb_remove_function);
 381
 382 /**
 383  * usb_function_deactivate - prevent function and gadget enumeration
 384  * @function: the function that isn't yet ready to respond
 385  *
 386  * Blocks response of the gadget driver to host enumeration by
 387  * preventing the data line pullup from being activated.  This is
 388  * normally called during @bind() processing to change from the
 389  * initial "ready to respond" state, or when a required resource
 390  * becomes available.
 391  *
 392  * For example, drivers that serve as a passthrough to a userspace
 393  * daemon can block enumeration unless that daemon (such as an OBEX,
 394  * MTP, or print server) is ready to handle host requests.
 395  *
 396  * Not all systems support software control of their USB peripheral
 397  * data pullups.
 398  *
 399  * Returns zero on success, else negative errno.
 400  */
 401 int usb_function_deactivate(struct usb_function *function)
 402 {
 403         struct usb_composite_dev        *cdev = function->config->cdev;
 404         unsigned long                   flags;
 405         int                             status = 0;
 406
 407         spin_lock_irqsave(&cdev->lock, flags);
 408
 409         if (cdev->deactivations == 0) {
 410                 spin_unlock_irqrestore(&cdev->lock, flags);
 411                 status = usb_gadget_deactivate(cdev->gadget);
 412                 spin_lock_irqsave(&cdev->lock, flags);
 413         }
 414         if (status == 0)
 415                 cdev->deactivations++;
 416
 417         spin_unlock_irqrestore(&cdev->lock, flags);
 418         return status;
 419 }
 420 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 421
 422 /**
 423  * usb_function_activate - allow function and gadget enumeration
 424  * @function: function on which usb_function_activate() was called
 425  *
 426  * Reverses effect of usb_function_deactivate().  If no more functions
 427  * are delaying their activation, the gadget driver will respond to
 428  * host enumeration procedures.
 429  *
 430  * Returns zero on success, else negative errno.
 431  */
 432 int usb_function_activate(struct usb_function *function)
 433 {
 434         struct usb_composite_dev        *cdev = function->config->cdev;
 435         unsigned long                   flags;
 436         int                             status = 0;
 437
 438         spin_lock_irqsave(&cdev->lock, flags);
 439
 440         if (WARN_ON(cdev->deactivations == 0))
 441                 status = -EINVAL;
 442         else {
 443                 cdev->deactivations--;
 444                 if (cdev->deactivations == 0) {
 445                         spin_unlock_irqrestore(&cdev->lock, flags);
 446                         status = usb_gadget_activate(cdev->gadget);
 447                         spin_lock_irqsave(&cdev->lock, flags);
 448                 }
 449         }
 450
 451         spin_unlock_irqrestore(&cdev->lock, flags);
 452         return status;
 453 }
 454 EXPORT_SYMBOL_GPL(usb_function_activate);
 455
 456 /**
 457  * usb_interface_id() - allocate an unused interface ID
 458  * @config: configuration associated with the interface
 459  * @function: function handling the interface
 460  * Context: single threaded during gadget setup
 461  *
 462  * usb_interface_id() is called from usb_function.bind() callbacks to
 463  * allocate new interface IDs.  The function driver will then store that
 464  * ID in interface, association, CDC union, and other descriptors.  It
 465  * will also handle any control requests targeted at that interface,
 466  * particularly changing its altsetting via set_alt().  There may
 467  * also be class-specific or vendor-specific requests to handle.
 468  *
 469  * All interface identifier should be allocated using this routine, to
 470  * ensure that for example different functions don't wrongly assign
 471  * different meanings to the same identifier.  Note that since interface
 472  * identifiers are configuration-specific, functions used in more than
 473  * one configuration (or more than once in a given configuration) need
 474  * multiple versions of the relevant descriptors.
 475  *
 476  * Returns the interface ID which was allocated; or -ENODEV if no
 477  * more interface IDs can be allocated.
 478  */
 479 int usb_interface_id(struct usb_configuration *config,
 480                 struct usb_function *function)
 481 {
 482         unsigned id = config->next_interface_id;
 483
 484         if (id < MAX_CONFIG_INTERFACES) {
 485                 config->interface[id] = function;
 486                 config->next_interface_id = id + 1;
 487                 return id;
 488         }
 489         return -ENODEV;
 490 }
 491 EXPORT_SYMBOL_GPL(usb_interface_id);
 492
 493 static u8 encode_bMaxPower(enum usb_device_speed speed,
 494                 struct usb_configuration *c)
 495 {
 496         unsigned val;
 497
 498         if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 499                 val = c->MaxPower;
 500         else
 501                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 502         if (!val)
 503                 return 0;
 504         if (speed < USB_SPEED_SUPER)
 505                 return min(val, 500U) / 2;
 506         else
 507                 /*
 508                  * USB 3.x supports up to 900mA, but since 900 isn't divisible
 509                  * by 8 the integral division will effectively cap to 896mA.
 510                  */
 511                 return min(val, 900U) / 8;
 512 }
 513
 514 static int config_buf(struct usb_configuration *config,
 515                 enum usb_device_speed speed, void *buf, u8 type)
 516 {
 517         struct usb_config_descriptor    *c = buf;
 518         void                            *next = buf + USB_DT_CONFIG_SIZE;
 519         int                             len;
 520         struct usb_function             *f;
 521         int                             status;
 522
 523         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 524         /* write the config descriptor */
 525         c = buf;
 526         c->bLength = USB_DT_CONFIG_SIZE;
 527         c->bDescriptorType = type;
 528         /* wTotalLength is written later */
 529         c->bNumInterfaces = config->next_interface_id;
 530         c->bConfigurationValue = config->bConfigurationValue;
 531         c->iConfiguration = config->iConfiguration;
 532         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 533         c->bMaxPower = encode_bMaxPower(speed, config);
 534
 535         /* There may be e.g. OTG descriptors */
 536         if (config->descriptors) {
 537                 status = usb_descriptor_fillbuf(next, len,
 538                                 config->descriptors);
 539                 if (status < 0)
 540                         return status;
 541                 len -= status;
 542                 next += status;
 543         }
 544
 545         /* add each function's descriptors */
 546         list_for_each_entry(f, &config->functions, list) {
 547                 struct usb_descriptor_header **descriptors;
 548
 549                 descriptors = function_descriptors(f, speed);
 550                 if (!descriptors)
 551                         continue;
 552                 status = usb_descriptor_fillbuf(next, len,
 553                         (const struct usb_descriptor_header **) descriptors);
 554                 if (status < 0)
 555                         return status;
 556                 len -= status;
 557                 next += status;
 558         }
 559
 560         len = next - buf;
 561         c->wTotalLength = cpu_to_le16(len);
 562         return len;
 563 }
 564
 565 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 566 {
 567         struct usb_gadget               *gadget = cdev->gadget;
 568         struct usb_configuration        *c;
 569         struct list_head                *pos;
 570         u8                              type = w_value >> 8;
 571         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 572
 573         if (gadget->speed >= USB_SPEED_SUPER)
 574                 speed = gadget->speed;
 575         else if (gadget_is_dualspeed(gadget)) {
 576                 int     hs = 0;
 577                 if (gadget->speed == USB_SPEED_HIGH)
 578                         hs = 1;
 579                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 580                         hs = !hs;
 581                 if (hs)
 582                         speed = USB_SPEED_HIGH;
 583
 584         }
 585
 586         /* This is a lookup by config *INDEX* */
 587         w_value &= 0xff;
 588
 589         pos = &cdev->configs;
 590         c = cdev->os_desc_config;
 591         if (c)
 592                 goto check_config;
 593
 594         while ((pos = pos->next) !=  &cdev->configs) {
 595                 c = list_entry(pos, typeof(*c), list);
 596
 597                 /* skip OS Descriptors config which is handled separately */
 598                 if (c == cdev->os_desc_config)
 599                         continue;
 600
 601 check_config:
 602                 /* ignore configs that won't work at this speed */
 603                 switch (speed) {
 604                 case USB_SPEED_SUPER_PLUS:
 605                         if (!c->superspeed_plus)
 606                                 continue;
 607                         break;
 608                 case USB_SPEED_SUPER:
 609                         if (!c->superspeed)
 610                                 continue;
 611                         break;
 612                 case USB_SPEED_HIGH:
 613                         if (!c->highspeed)
 614                                 continue;
 615                         break;
 616                 default:
 617                         if (!c->fullspeed)
 618                                 continue;
 619                 }
 620
 621                 if (w_value == 0)
 622                         return config_buf(c, speed, cdev->req->buf, type);
 623                 w_value--;
 624         }
 625         return -EINVAL;
 626 }
 627
 628 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 629 {
 630         struct usb_gadget               *gadget = cdev->gadget;
 631         struct usb_configuration        *c;
 632         unsigned                        count = 0;
 633         int                             hs = 0;
 634         int                             ss = 0;
 635         int                             ssp = 0;
 636
 637         if (gadget_is_dualspeed(gadget)) {
 638                 if (gadget->speed == USB_SPEED_HIGH)
 639                         hs = 1;
 640                 if (gadget->speed == USB_SPEED_SUPER)
 641                         ss = 1;
 642                 if (gadget->speed == USB_SPEED_SUPER_PLUS)
 643                         ssp = 1;
 644                 if (type == USB_DT_DEVICE_QUALIFIER)
 645                         hs = !hs;
 646         }
 647         list_for_each_entry(c, &cdev->configs, list) {
 648                 /* ignore configs that won't work at this speed */
 649                 if (ssp) {
 650                         if (!c->superspeed_plus)
 651                                 continue;
 652                 } else if (ss) {
 653                         if (!c->superspeed)
 654                                 continue;
 655                 } else if (hs) {
 656                         if (!c->highspeed)
 657                                 continue;
 658                 } else {
 659                         if (!c->fullspeed)
 660                                 continue;
 661                 }
 662                 count++;
 663         }
 664         return count;
 665 }
 666
 667 /**
 668  * bos_desc() - prepares the BOS descriptor.
 669  * @cdev: pointer to usb_composite device to generate the bos
 670  *      descriptor for
 671  *
 672  * This function generates the BOS (Binary Device Object)
 673  * descriptor and its device capabilities descriptors. The BOS
 674  * descriptor should be supported by a SuperSpeed device.
 675  */
 676 static int bos_desc(struct usb_composite_dev *cdev)
 677 {
 678         struct usb_ext_cap_descriptor   *usb_ext;
 679         struct usb_dcd_config_params    dcd_config_params;
 680         struct usb_bos_descriptor       *bos = cdev->req->buf;
 681         unsigned int                    besl = 0;
 682
 683         bos->bLength = USB_DT_BOS_SIZE;
 684         bos->bDescriptorType = USB_DT_BOS;
 685
 686         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 687         bos->bNumDeviceCaps = 0;
 688
 689         /* Get Controller configuration */
 690         if (cdev->gadget->ops->get_config_params) {
 691                 cdev->gadget->ops->get_config_params(cdev->gadget,
 692                                                      &dcd_config_params);
 693         } else {
 694                 dcd_config_params.besl_baseline =
 695                         USB_DEFAULT_BESL_UNSPECIFIED;
 696                 dcd_config_params.besl_deep =
 697                         USB_DEFAULT_BESL_UNSPECIFIED;
 698                 dcd_config_params.bU1devExitLat =
 699                         USB_DEFAULT_U1_DEV_EXIT_LAT;
 700                 dcd_config_params.bU2DevExitLat =
 701                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 702         }
 703
 704         if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
 705                 besl = USB_BESL_BASELINE_VALID |
 706                         USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
 707
 708         if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
 709                 besl |= USB_BESL_DEEP_VALID |
 710                         USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
 711
 712         /*
 713          * A SuperSpeed device shall include the USB2.0 extension descriptor
 714          * and shall support LPM when operating in USB2.0 HS mode.
 715          */
 716         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 717         bos->bNumDeviceCaps++;
 718         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 719         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 720         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 721         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 722         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
 723                                             USB_BESL_SUPPORT | besl);
 724
 725         /*
 726          * The Superspeed USB Capability descriptor shall be implemented by all
 727          * SuperSpeed devices.
 728          */
 729         if (gadget_is_superspeed(cdev->gadget)) {
 730                 struct usb_ss_cap_descriptor *ss_cap;
 731
 732                 ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 733                 bos->bNumDeviceCaps++;
 734                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 735                 ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 736                 ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 737                 ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 738                 ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 739                 ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 740                                                       USB_FULL_SPEED_OPERATION |
 741                                                       USB_HIGH_SPEED_OPERATION |
 742                                                       USB_5GBPS_OPERATION);
 743                 ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 744                 ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 745                 ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 746         }
 747
 748         /* The SuperSpeedPlus USB Device Capability descriptor */
 749         if (gadget_is_superspeed_plus(cdev->gadget)) {
 750                 struct usb_ssp_cap_descriptor *ssp_cap;
 751                 u8 ssac = 1;
 752                 u8 ssic;
 753                 int i;
 754
 755                 if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x2)
 756                         ssac = 3;
 757
 758                 /*
 759                  * Paired RX and TX sublink speed attributes share
 760                  * the same SSID.
 761                  */
 762                 ssic = (ssac + 1) / 2 - 1;
 763
 764                 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 765                 bos->bNumDeviceCaps++;
 766
 767                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
 768                 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
 769                 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 770                 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 771                 ssp_cap->bReserved = 0;
 772                 ssp_cap->wReserved = 0;
 773
 774                 ssp_cap->bmAttributes =
 775                         cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
 776                                     FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
 777
 778                 ssp_cap->wFunctionalitySupport =
 779                         cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
 780                                     FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
 781                                     FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 782
 783                 /*
 784                  * Use 1 SSID if the gadget supports up to gen2x1 or not
 785                  * specified:
 786                  * - SSID 0 for symmetric RX/TX sublink speed of 10 Gbps.
 787                  *
 788                  * Use 1 SSID if the gadget supports up to gen1x2:
 789                  * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 790                  *
 791                  * Use 2 SSIDs if the gadget supports up to gen2x2:
 792                  * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 793                  * - SSID 1 for symmetric RX/TX sublink speed of 10 Gbps.
 794                  */
 795                 for (i = 0; i < ssac + 1; i++) {
 796                         u8 ssid;
 797                         u8 mantissa;
 798                         u8 type;
 799
 800                         ssid = i >> 1;
 801
 802                         if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x1 ||
 803                             cdev->gadget->max_ssp_rate == USB_SSP_GEN_UNKNOWN)
 804                                 mantissa = 10;
 805                         else
 806                                 mantissa = 5 << ssid;
 807
 808                         if (i % 2)
 809                                 type = USB_SSP_SUBLINK_SPEED_ST_SYM_TX;
 810                         else
 811                                 type = USB_SSP_SUBLINK_SPEED_ST_SYM_RX;
 812
 813                         ssp_cap->bmSublinkSpeedAttr[i] =
 814                                 cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ssid) |
 815                                             FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE,
 816                                                        USB_SSP_SUBLINK_SPEED_LSE_GBPS) |
 817                                             FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, type) |
 818                                             FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP,
 819                                                        USB_SSP_SUBLINK_SPEED_LP_SSP) |
 820                                             FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, mantissa));
 821                 }
 822         }
 823
 824         return le16_to_cpu(bos->wTotalLength);
 825 }
 826
 827 static void device_qual(struct usb_composite_dev *cdev)
 828 {
 829         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 830
 831         qual->bLength = sizeof(*qual);
 832         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 833         /* POLICY: same bcdUSB and device type info at both speeds */
 834         qual->bcdUSB = cdev->desc.bcdUSB;
 835         qual->bDeviceClass = cdev->desc.bDeviceClass;
 836         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 837         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 838         /* ASSUME same EP0 fifo size at both speeds */
 839         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 840         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 841         qual->bRESERVED = 0;
 842 }
 843
 844 /*-------------------------------------------------------------------------*/
 845
 846 static void reset_config(struct usb_composite_dev *cdev)
 847 {
 848         struct usb_function             *f;
 849
 850         DBG(cdev, "reset config\n");
 851
 852         list_for_each_entry(f, &cdev->config->functions, list) {
 853                 if (f->disable)
 854                         f->disable(f);
 855
 856                 bitmap_zero(f->endpoints, 32);
 857         }
 858         cdev->config = NULL;
 859         cdev->delayed_status = 0;
 860 }
 861
 862 static int set_config(struct usb_composite_dev *cdev,
 863                 const struct usb_ctrlrequest *ctrl, unsigned number)
 864 {
 865         struct usb_gadget       *gadget = cdev->gadget;
 866         struct usb_configuration *c = NULL;
 867         int                     result = -EINVAL;
 868         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 869         int                     tmp;
 870
 871         if (number) {
 872                 list_for_each_entry(c, &cdev->configs, list) {
 873                         if (c->bConfigurationValue == number) {
 874                                 /*
 875                                  * We disable the FDs of the previous
 876                                  * configuration only if the new configuration
 877                                  * is a valid one
 878                                  */
 879                                 if (cdev->config)
 880                                         reset_config(cdev);
 881                                 result = 0;
 882                                 break;
 883                         }
 884                 }
 885                 if (result < 0)
 886                         goto done;
 887         } else { /* Zero configuration value - need to reset the config */
 888                 if (cdev->config)
 889                         reset_config(cdev);
 890                 result = 0;
 891         }
 892
 893         DBG(cdev, "%s config #%d: %s\n",
 894             usb_speed_string(gadget->speed),
 895             number, c ? c->label : "unconfigured");
 896
 897         if (!c)
 898                 goto done;
 899
 900         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 901         cdev->config = c;
 902
 903         /* Initialize all interfaces by setting them to altsetting zero. */
 904         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 905                 struct usb_function     *f = c->interface[tmp];
 906                 struct usb_descriptor_header **descriptors;
 907
 908                 if (!f)
 909                         break;
 910
 911                 /*
 912                  * Record which endpoints are used by the function. This is used
 913                  * to dispatch control requests targeted at that endpoint to the
 914                  * function's setup callback instead of the current
 915                  * configuration's setup callback.
 916                  */
 917                 descriptors = function_descriptors(f, gadget->speed);
 918
 919                 for (; *descriptors; ++descriptors) {
 920                         struct usb_endpoint_descriptor *ep;
 921                         int addr;
 922
 923                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 924                                 continue;
 925
 926                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 927                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 928                              |  (ep->bEndpointAddress & 0x0f);
 929                         set_bit(addr, f->endpoints);
 930                 }
 931
 932                 result = f->set_alt(f, tmp, 0);
 933                 if (result < 0) {
 934                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 935                                         tmp, f->name, f, result);
 936
 937                         reset_config(cdev);
 938                         goto done;
 939                 }
 940
 941                 if (result == USB_GADGET_DELAYED_STATUS) {
 942                         DBG(cdev,
 943                          "%s: interface %d (%s) requested delayed status\n",
 944                                         __func__, tmp, f->name);
 945                         cdev->delayed_status++;
 946                         DBG(cdev, "delayed_status count %d\n",
 947                                         cdev->delayed_status);
 948                 }
 949         }
 950
 951         /* when we return, be sure our power usage is valid */
 952         if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 953                 power = c->MaxPower;
 954         else
 955                 power = CONFIG_USB_GADGET_VBUS_DRAW;
 956
 957         if (gadget->speed < USB_SPEED_SUPER)
 958                 power = min(power, 500U);
 959         else
 960                 power = min(power, 900U);
 961 done:
 962         if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
 963                 usb_gadget_set_selfpowered(gadget);
 964         else
 965                 usb_gadget_clear_selfpowered(gadget);
 966
 967         usb_gadget_vbus_draw(gadget, power);
 968         if (result >= 0 && cdev->delayed_status)
 969                 result = USB_GADGET_DELAYED_STATUS;
 970         return result;
 971 }
 972
 973 int usb_add_config_only(struct usb_composite_dev *cdev,
 974                 struct usb_configuration *config)
 975 {
 976         struct usb_configuration *c;
 977
 978         if (!config->bConfigurationValue)
 979                 return -EINVAL;
 980
 981         /* Prevent duplicate configuration identifiers */
 982         list_for_each_entry(c, &cdev->configs, list) {
 983                 if (c->bConfigurationValue == config->bConfigurationValue)
 984                         return -EBUSY;
 985         }
 986
 987         config->cdev = cdev;
 988         list_add_tail(&config->list, &cdev->configs);
 989
 990         INIT_LIST_HEAD(&config->functions);
 991         config->next_interface_id = 0;
 992         memset(config->interface, 0, sizeof(config->interface));
 993
 994         return 0;
 995 }
 996 EXPORT_SYMBOL_GPL(usb_add_config_only);
 997
 998 /**
 999  * usb_add_config() - add a configuration to a device.
1000  * @cdev: wraps the USB gadget
1001  * @config: the configuration, with bConfigurationValue assigned
1002  * @bind: the configuration's bind function
1003  * Context: single threaded during gadget setup
1004  *
1005  * One of the main tasks of a composite @bind() routine is to
1006  * add each of the configurations it supports, using this routine.
1007  *
1008  * This function returns the value of the configuration's @bind(), which
1009  * is zero for success else a negative errno value.  Binding configurations
1010  * assigns global resources including string IDs, and per-configuration
1011  * resources such as interface IDs and endpoints.
1012  */
1013 int usb_add_config(struct usb_composite_dev *cdev,
1014                 struct usb_configuration *config,
1015                 int (*bind)(struct usb_configuration *))
1016 {
1017         int                             status = -EINVAL;
1018
1019         if (!bind)
1020                 goto done;
1021
1022         DBG(cdev, "adding config #%u '%s'/%p\n",
1023                         config->bConfigurationValue,
1024                         config->label, config);
1025
1026         status = usb_add_config_only(cdev, config);
1027         if (status)
1028                 goto done;
1029
1030         status = bind(config);
1031         if (status < 0) {
1032                 while (!list_empty(&config->functions)) {
1033                         struct usb_function             *f;
1034
1035                         f = list_first_entry(&config->functions,
1036                                         struct usb_function, list);
1037                         list_del(&f->list);
1038                         if (f->unbind) {
1039                                 DBG(cdev, "unbind function '%s'/%p\n",
1040                                         f->name, f);
1041                                 f->unbind(config, f);
1042                                 /* may free memory for "f" */
1043                         }
1044                 }
1045                 list_del(&config->list);
1046                 config->cdev = NULL;
1047         } else {
1048                 unsigned        i;
1049
1050                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1051                         config->bConfigurationValue, config,
1052                         config->superspeed_plus ? " superplus" : "",
1053                         config->superspeed ? " super" : "",
1054                         config->highspeed ? " high" : "",
1055                         config->fullspeed
1056                                 ? (gadget_is_dualspeed(cdev->gadget)
1057                                         ? " full"
1058                                         : " full/low")
1059                                 : "");
1060
1061                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1062                         struct usb_function     *f = config->interface[i];
1063
1064                         if (!f)
1065                                 continue;
1066                         DBG(cdev, "  interface %d = %s/%p\n",
1067                                 i, f->name, f);
1068                 }
1069         }
1070
1071         /* set_alt(), or next bind(), sets up ep->claimed as needed */
1072         usb_ep_autoconfig_reset(cdev->gadget);
1073
1074 done:
1075         if (status)
1076                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1077                                 config->bConfigurationValue, status);
1078         return status;
1079 }
1080 EXPORT_SYMBOL_GPL(usb_add_config);
1081
1082 static void remove_config(struct usb_composite_dev *cdev,
1083                               struct usb_configuration *config)
1084 {
1085         while (!list_empty(&config->functions)) {
1086                 struct usb_function             *f;
1087
1088                 f = list_first_entry(&config->functions,
1089                                 struct usb_function, list);
1090
1091                 usb_remove_function(config, f);
1092         }
1093         list_del(&config->list);
1094         if (config->unbind) {
1095                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1096                 config->unbind(config);
1097                         /* may free memory for "c" */
1098         }
1099 }
1100
1101 /**
1102  * usb_remove_config() - remove a configuration from a device.
1103  * @cdev: wraps the USB gadget
1104  * @config: the configuration
1105  *
1106  * Drivers must call usb_gadget_disconnect before calling this function
1107  * to disconnect the device from the host and make sure the host will not
1108  * try to enumerate the device while we are changing the config list.
1109  */
1110 void usb_remove_config(struct usb_composite_dev *cdev,
1111                       struct usb_configuration *config)
1112 {
1113         unsigned long flags;
1114
1115         spin_lock_irqsave(&cdev->lock, flags);
1116
1117         if (cdev->config == config)
1118                 reset_config(cdev);
1119
1120         spin_unlock_irqrestore(&cdev->lock, flags);
1121
1122         remove_config(cdev, config);
1123 }
1124
1125 /*-------------------------------------------------------------------------*/
1126
1127 /* We support strings in multiple languages ... string descriptor zero
1128  * says which languages are supported.  The typical case will be that
1129  * only one language (probably English) is used, with i18n handled on
1130  * the host side.
1131  */
1132
1133 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1134 {
1135         const struct usb_gadget_strings *s;
1136         __le16                          language;
1137         __le16                          *tmp;
1138
1139         while (*sp) {
1140                 s = *sp;
1141                 language = cpu_to_le16(s->language);
1142                 for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1143                         if (*tmp == language)
1144                                 goto repeat;
1145                 }
1146                 *tmp++ = language;
1147 repeat:
1148                 sp++;
1149         }
1150 }
1151
1152 static int lookup_string(
1153         struct usb_gadget_strings       **sp,
1154         void                            *buf,
1155         u16                             language,
1156         int                             id
1157 )
1158 {
1159         struct usb_gadget_strings       *s;
1160         int                             value;
1161
1162         while (*sp) {
1163                 s = *sp++;
1164                 if (s->language != language)
1165                         continue;
1166                 value = usb_gadget_get_string(s, id, buf);
1167                 if (value > 0)
1168                         return value;
1169         }
1170         return -EINVAL;
1171 }
1172
1173 static int get_string(struct usb_composite_dev *cdev,
1174                 void *buf, u16 language, int id)
1175 {
1176         struct usb_composite_driver     *composite = cdev->driver;
1177         struct usb_gadget_string_container *uc;
1178         struct usb_configuration        *c;
1179         struct usb_function             *f;
1180         int                             len;
1181
1182         /* Yes, not only is USB's i18n support probably more than most
1183          * folk will ever care about ... also, it's all supported here.
1184          * (Except for UTF8 support for Unicode's "Astral Planes".)
1185          */
1186
1187         /* 0 == report all available language codes */
1188         if (id == 0) {
1189                 struct usb_string_descriptor    *s = buf;
1190                 struct usb_gadget_strings       **sp;
1191
1192                 memset(s, 0, 256);
1193                 s->bDescriptorType = USB_DT_STRING;
1194
1195                 sp = composite->strings;
1196                 if (sp)
1197                         collect_langs(sp, s->wData);
1198
1199                 list_for_each_entry(c, &cdev->configs, list) {
1200                         sp = c->strings;
1201                         if (sp)
1202                                 collect_langs(sp, s->wData);
1203
1204                         list_for_each_entry(f, &c->functions, list) {
1205                                 sp = f->strings;
1206                                 if (sp)
1207                                         collect_langs(sp, s->wData);
1208                         }
1209                 }
1210                 list_for_each_entry(uc, &cdev->gstrings, list) {
1211                         struct usb_gadget_strings **sp;
1212
1213                         sp = get_containers_gs(uc);
1214                         collect_langs(sp, s->wData);
1215                 }
1216
1217                 for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1218                         continue;
1219                 if (!len)
1220                         return -EINVAL;
1221
1222                 s->bLength = 2 * (len + 1);
1223                 return s->bLength;
1224         }
1225
1226         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1227                 struct usb_os_string *b = buf;
1228                 b->bLength = sizeof(*b);
1229                 b->bDescriptorType = USB_DT_STRING;
1230                 compiletime_assert(
1231                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1232                         "qwSignature size must be equal to qw_sign");
1233                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1234                 b->bMS_VendorCode = cdev->b_vendor_code;
1235                 b->bPad = 0;
1236                 return sizeof(*b);
1237         }
1238
1239         list_for_each_entry(uc, &cdev->gstrings, list) {
1240                 struct usb_gadget_strings **sp;
1241
1242                 sp = get_containers_gs(uc);
1243                 len = lookup_string(sp, buf, language, id);
1244                 if (len > 0)
1245                         return len;
1246         }
1247
1248         /* String IDs are device-scoped, so we look up each string
1249          * table we're told about.  These lookups are infrequent;
1250          * simpler-is-better here.
1251          */
1252         if (composite->strings) {
1253                 len = lookup_string(composite->strings, buf, language, id);
1254                 if (len > 0)
1255                         return len;
1256         }
1257         list_for_each_entry(c, &cdev->configs, list) {
1258                 if (c->strings) {
1259                         len = lookup_string(c->strings, buf, language, id);
1260                         if (len > 0)
1261                                 return len;
1262                 }
1263                 list_for_each_entry(f, &c->functions, list) {
1264                         if (!f->strings)
1265                                 continue;
1266                         len = lookup_string(f->strings, buf, language, id);
1267                         if (len > 0)
1268                                 return len;
1269                 }
1270         }
1271         return -EINVAL;
1272 }
1273
1274 /**
1275  * usb_string_id() - allocate an unused string ID
1276  * @cdev: the device whose string descriptor IDs are being allocated
1277  * Context: single threaded during gadget setup
1278  *
1279  * @usb_string_id() is called from bind() callbacks to allocate
1280  * string IDs.  Drivers for functions, configurations, or gadgets will
1281  * then store that ID in the appropriate descriptors and string table.
1282  *
1283  * All string identifier should be allocated using this,
1284  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1285  * that for example different functions don't wrongly assign different
1286  * meanings to the same identifier.
1287  */
1288 int usb_string_id(struct usb_composite_dev *cdev)
1289 {
1290         if (cdev->next_string_id < 254) {
1291                 /* string id 0 is reserved by USB spec for list of
1292                  * supported languages */
1293                 /* 255 reserved as well? -- mina86 */
1294                 cdev->next_string_id++;
1295                 return cdev->next_string_id;
1296         }
1297         return -ENODEV;
1298 }
1299 EXPORT_SYMBOL_GPL(usb_string_id);
1300
1301 /**
1302  * usb_string_ids_tab() - allocate unused string IDs in batch
1303  * @cdev: the device whose string descriptor IDs are being allocated
1304  * @str: an array of usb_string objects to assign numbers to
1305  * Context: single threaded during gadget setup
1306  *
1307  * @usb_string_ids() is called from bind() callbacks to allocate
1308  * string IDs.  Drivers for functions, configurations, or gadgets will
1309  * then copy IDs from the string table to the appropriate descriptors
1310  * and string table for other languages.
1311  *
1312  * All string identifier should be allocated using this,
1313  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1314  * example different functions don't wrongly assign different meanings
1315  * to the same identifier.
1316  */
1317 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1318 {
1319         int next = cdev->next_string_id;
1320
1321         for (; str->s; ++str) {
1322                 if (unlikely(next >= 254))
1323                         return -ENODEV;
1324                 str->id = ++next;
1325         }
1326
1327         cdev->next_string_id = next;
1328
1329         return 0;
1330 }
1331 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1332
1333 static struct usb_gadget_string_container *copy_gadget_strings(
1334                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1335                 unsigned n_strings)
1336 {
1337         struct usb_gadget_string_container *uc;
1338         struct usb_gadget_strings **gs_array;
1339         struct usb_gadget_strings *gs;
1340         struct usb_string *s;
1341         unsigned mem;
1342         unsigned n_gs;
1343         unsigned n_s;
1344         void *stash;
1345
1346         mem = sizeof(*uc);
1347         mem += sizeof(void *) * (n_gstrings + 1);
1348         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1349         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1350         uc = kmalloc(mem, GFP_KERNEL);
1351         if (!uc)
1352                 return ERR_PTR(-ENOMEM);
1353         gs_array = get_containers_gs(uc);
1354         stash = uc->stash;
1355         stash += sizeof(void *) * (n_gstrings + 1);
1356         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1357                 struct usb_string *org_s;
1358
1359                 gs_array[n_gs] = stash;
1360                 gs = gs_array[n_gs];
1361                 stash += sizeof(struct usb_gadget_strings);
1362                 gs->language = sp[n_gs]->language;
1363                 gs->strings = stash;
1364                 org_s = sp[n_gs]->strings;
1365
1366                 for (n_s = 0; n_s < n_strings; n_s++) {
1367                         s = stash;
1368                         stash += sizeof(struct usb_string);
1369                         if (org_s->s)
1370                                 s->s = org_s->s;
1371                         else
1372                                 s->s = "";
1373                         org_s++;
1374                 }
1375                 s = stash;
1376                 s->s = NULL;
1377                 stash += sizeof(struct usb_string);
1378
1379         }
1380         gs_array[n_gs] = NULL;
1381         return uc;
1382 }
1383
1384 /**
1385  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1386  * @cdev: the device whose string descriptor IDs are being allocated
1387  * and attached.
1388  * @sp: an array of usb_gadget_strings to attach.
1389  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1390  *
1391  * This function will create a deep copy of usb_gadget_strings and usb_string
1392  * and attach it to the cdev. The actual string (usb_string.s) will not be
1393  * copied but only a referenced will be made. The struct usb_gadget_strings
1394  * array may contain multiple languages and should be NULL terminated.
1395  * The ->language pointer of each struct usb_gadget_strings has to contain the
1396  * same amount of entries.
1397  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1398  * usb_string entry of es-ES contains the translation of the first usb_string
1399  * entry of en-US. Therefore both entries become the same id assign.
1400  */
1401 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1402                 struct usb_gadget_strings **sp, unsigned n_strings)
1403 {
1404         struct usb_gadget_string_container *uc;
1405         struct usb_gadget_strings **n_gs;
1406         unsigned n_gstrings = 0;
1407         unsigned i;
1408         int ret;
1409
1410         for (i = 0; sp[i]; i++)
1411                 n_gstrings++;
1412
1413         if (!n_gstrings)
1414                 return ERR_PTR(-EINVAL);
1415
1416         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1417         if (IS_ERR(uc))
1418                 return ERR_CAST(uc);
1419
1420         n_gs = get_containers_gs(uc);
1421         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1422         if (ret)
1423                 goto err;
1424
1425         for (i = 1; i < n_gstrings; i++) {
1426                 struct usb_string *m_s;
1427                 struct usb_string *s;
1428                 unsigned n;
1429
1430                 m_s = n_gs[0]->strings;
1431                 s = n_gs[i]->strings;
1432                 for (n = 0; n < n_strings; n++) {
1433                         s->id = m_s->id;
1434                         s++;
1435                         m_s++;
1436                 }
1437         }
1438         list_add_tail(&uc->list, &cdev->gstrings);
1439         return n_gs[0]->strings;
1440 err:
1441         kfree(uc);
1442         return ERR_PTR(ret);
1443 }
1444 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1445
1446 /**
1447  * usb_string_ids_n() - allocate unused string IDs in batch
1448  * @c: the device whose string descriptor IDs are being allocated
1449  * @n: number of string IDs to allocate
1450  * Context: single threaded during gadget setup
1451  *
1452  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1453  * valid IDs.  At least provided that @n is non-zero because if it
1454  * is, returns last requested ID which is now very useful information.
1455  *
1456  * @usb_string_ids_n() is called from bind() callbacks to allocate
1457  * string IDs.  Drivers for functions, configurations, or gadgets will
1458  * then store that ID in the appropriate descriptors and string table.
1459  *
1460  * All string identifier should be allocated using this,
1461  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1462  * example different functions don't wrongly assign different meanings
1463  * to the same identifier.
1464  */
1465 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1466 {
1467         unsigned next = c->next_string_id;
1468         if (unlikely(n > 254 || (unsigned)next + n > 254))
1469                 return -ENODEV;
1470         c->next_string_id += n;
1471         return next + 1;
1472 }
1473 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1474
1475 /*-------------------------------------------------------------------------*/
1476
1477 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1478 {
1479         struct usb_composite_dev *cdev;
1480
1481         if (req->status || req->actual != req->length)
1482                 DBG((struct usb_composite_dev *) ep->driver_data,
1483                                 "setup complete --> %d, %d/%d\n",
1484                                 req->status, req->actual, req->length);
1485
1486         /*
1487          * REVIST The same ep0 requests are shared with function drivers
1488          * so they don't have to maintain the same ->complete() stubs.
1489          *
1490          * Because of that, we need to check for the validity of ->context
1491          * here, even though we know we've set it to something useful.
1492          */
1493         if (!req->context)
1494                 return;
1495
1496         cdev = req->context;
1497
1498         if (cdev->req == req)
1499                 cdev->setup_pending = false;
1500         else if (cdev->os_desc_req == req)
1501                 cdev->os_desc_pending = false;
1502         else
1503                 WARN(1, "unknown request %p\n", req);
1504 }
1505
1506 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1507                 struct usb_request *req, gfp_t gfp_flags)
1508 {
1509         int ret;
1510
1511         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1512         if (ret == 0) {
1513                 if (cdev->req == req)
1514                         cdev->setup_pending = true;
1515                 else if (cdev->os_desc_req == req)
1516                         cdev->os_desc_pending = true;
1517                 else
1518                         WARN(1, "unknown request %p\n", req);
1519         }
1520
1521         return ret;
1522 }
1523
1524 static int count_ext_compat(struct usb_configuration *c)
1525 {
1526         int i, res;
1527
1528         res = 0;
1529         for (i = 0; i < c->next_interface_id; ++i) {
1530                 struct usb_function *f;
1531                 int j;
1532
1533                 f = c->interface[i];
1534                 for (j = 0; j < f->os_desc_n; ++j) {
1535                         struct usb_os_desc *d;
1536
1537                         if (i != f->os_desc_table[j].if_id)
1538                                 continue;
1539                         d = f->os_desc_table[j].os_desc;
1540                         if (d && d->ext_compat_id)
1541                                 ++res;
1542                 }
1543         }
1544         BUG_ON(res > 255);
1545         return res;
1546 }
1547
1548 static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1549 {
1550         int i, count;
1551
1552         count = 16;
1553         buf += 16;
1554         for (i = 0; i < c->next_interface_id; ++i) {
1555                 struct usb_function *f;
1556                 int j;
1557
1558                 f = c->interface[i];
1559                 for (j = 0; j < f->os_desc_n; ++j) {
1560                         struct usb_os_desc *d;
1561
1562                         if (i != f->os_desc_table[j].if_id)
1563                                 continue;
1564                         d = f->os_desc_table[j].os_desc;
1565                         if (d && d->ext_compat_id) {
1566                                 *buf++ = i;
1567                                 *buf++ = 0x01;
1568                                 memcpy(buf, d->ext_compat_id, 16);
1569                                 buf += 22;
1570                         } else {
1571                                 ++buf;
1572                                 *buf = 0x01;
1573                                 buf += 23;
1574                         }
1575                         count += 24;
1576                         if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1577                                 return count;
1578                 }
1579         }
1580
1581         return count;
1582 }
1583
1584 static int count_ext_prop(struct usb_configuration *c, int interface)
1585 {
1586         struct usb_function *f;
1587         int j;
1588
1589         f = c->interface[interface];
1590         for (j = 0; j < f->os_desc_n; ++j) {
1591                 struct usb_os_desc *d;
1592
1593                 if (interface != f->os_desc_table[j].if_id)
1594                         continue;
1595                 d = f->os_desc_table[j].os_desc;
1596                 if (d && d->ext_compat_id)
1597                         return d->ext_prop_count;
1598         }
1599         return 0;
1600 }
1601
1602 static int len_ext_prop(struct usb_configuration *c, int interface)
1603 {
1604         struct usb_function *f;
1605         struct usb_os_desc *d;
1606         int j, res;
1607
1608         res = 10; /* header length */
1609         f = c->interface[interface];
1610         for (j = 0; j < f->os_desc_n; ++j) {
1611                 if (interface != f->os_desc_table[j].if_id)
1612                         continue;
1613                 d = f->os_desc_table[j].os_desc;
1614                 if (d)
1615                         return min(res + d->ext_prop_len, 4096);
1616         }
1617         return res;
1618 }
1619
1620 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1621 {
1622         struct usb_function *f;
1623         struct usb_os_desc *d;
1624         struct usb_os_desc_ext_prop *ext_prop;
1625         int j, count, n, ret;
1626
1627         f = c->interface[interface];
1628         count = 10; /* header length */
1629         buf += 10;
1630         for (j = 0; j < f->os_desc_n; ++j) {
1631                 if (interface != f->os_desc_table[j].if_id)
1632                         continue;
1633                 d = f->os_desc_table[j].os_desc;
1634                 if (d)
1635                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1636                                 n = ext_prop->data_len +
1637                                         ext_prop->name_len + 14;
1638                                 if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1639                                         return count;
1640                                 usb_ext_prop_put_size(buf, n);
1641                                 usb_ext_prop_put_type(buf, ext_prop->type);
1642                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1643                                                             ext_prop->name_len);
1644                                 if (ret < 0)
1645                                         return ret;
1646                                 switch (ext_prop->type) {
1647                                 case USB_EXT_PROP_UNICODE:
1648                                 case USB_EXT_PROP_UNICODE_ENV:
1649                                 case USB_EXT_PROP_UNICODE_LINK:
1650                                         usb_ext_prop_put_unicode(buf, ret,
1651                                                          ext_prop->data,
1652                                                          ext_prop->data_len);
1653                                         break;
1654                                 case USB_EXT_PROP_BINARY:
1655                                         usb_ext_prop_put_binary(buf, ret,
1656                                                         ext_prop->data,
1657                                                         ext_prop->data_len);
1658                                         break;
1659                                 case USB_EXT_PROP_LE32:
1660                                         /* not implemented */
1661                                 case USB_EXT_PROP_BE32:
1662                                         /* not implemented */
1663                                 default:
1664                                         return -EINVAL;
1665                                 }
1666                                 buf += n;
1667                                 count += n;
1668                         }
1669         }
1670
1671         return count;
1672 }
1673
1674 /*
1675  * The setup() callback implements all the ep0 functionality that's
1676  * not handled lower down, in hardware or the hardware driver(like
1677  * device and endpoint feature flags, and their status).  It's all
1678  * housekeeping for the gadget function we're implementing.  Most of
1679  * the work is in config and function specific setup.
1680  */
1681 int
1682 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1683 {
1684         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1685         struct usb_request              *req = cdev->req;
1686         int                             value = -EOPNOTSUPP;
1687         int                             status = 0;
1688         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1689         u8                              intf = w_index & 0xFF;
1690         u16                             w_value = le16_to_cpu(ctrl->wValue);
1691         u16                             w_length = le16_to_cpu(ctrl->wLength);
1692         struct usb_function             *f = NULL;
1693         u8                              endp;
1694
1695         if (w_length > USB_COMP_EP0_BUFSIZ) {
1696                 if (ctrl->bRequestType & USB_DIR_IN) {
1697                         /* Cast away the const, we are going to overwrite on purpose. */
1698                         __le16 *temp = (__le16 *)&ctrl->wLength;
1699
1700                         *temp = cpu_to_le16(USB_COMP_EP0_BUFSIZ);
1701                         w_length = USB_COMP_EP0_BUFSIZ;
1702                 } else {
1703                         goto done;
1704                 }
1705         }
1706
1707         /* partial re-init of the response message; the function or the
1708          * gadget might need to intercept e.g. a control-OUT completion
1709          * when we delegate to it.
1710          */
1711         req->zero = 0;
1712         req->context = cdev;
1713         req->complete = composite_setup_complete;
1714         req->length = 0;
1715         gadget->ep0->driver_data = cdev;
1716
1717         /*
1718          * Don't let non-standard requests match any of the cases below
1719          * by accident.
1720          */
1721         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1722                 goto unknown;
1723
1724         switch (ctrl->bRequest) {
1725
1726         /* we handle all standard USB descriptors */
1727         case USB_REQ_GET_DESCRIPTOR:
1728                 if (ctrl->bRequestType != USB_DIR_IN)
1729                         goto unknown;
1730                 switch (w_value >> 8) {
1731
1732                 case USB_DT_DEVICE:
1733                         cdev->desc.bNumConfigurations =
1734                                 count_configs(cdev, USB_DT_DEVICE);
1735                         cdev->desc.bMaxPacketSize0 =
1736                                 cdev->gadget->ep0->maxpacket;
1737                         if (gadget_is_superspeed(gadget)) {
1738                                 if (gadget->speed >= USB_SPEED_SUPER) {
1739                                         cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1740                                         cdev->desc.bMaxPacketSize0 = 9;
1741                                 } else {
1742                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1743                                 }
1744                         } else {
1745                                 if (gadget->lpm_capable)
1746                                         cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1747                                 else
1748                                         cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1749                         }
1750
1751                         value = min(w_length, (u16) sizeof cdev->desc);
1752                         memcpy(req->buf, &cdev->desc, value);
1753                         break;
1754                 case USB_DT_DEVICE_QUALIFIER:
1755                         if (!gadget_is_dualspeed(gadget) ||
1756                             gadget->speed >= USB_SPEED_SUPER)
1757                                 break;
1758                         device_qual(cdev);
1759                         value = min_t(int, w_length,
1760                                 sizeof(struct usb_qualifier_descriptor));
1761                         break;
1762                 case USB_DT_OTHER_SPEED_CONFIG:
1763                         if (!gadget_is_dualspeed(gadget) ||
1764                             gadget->speed >= USB_SPEED_SUPER)
1765                                 break;
1766                         fallthrough;
1767                 case USB_DT_CONFIG:
1768                         value = config_desc(cdev, w_value);
1769                         if (value >= 0)
1770                                 value = min(w_length, (u16) value);
1771                         break;
1772                 case USB_DT_STRING:
1773                         value = get_string(cdev, req->buf,
1774                                         w_index, w_value & 0xff);
1775                         if (value >= 0)
1776                                 value = min(w_length, (u16) value);
1777                         break;
1778                 case USB_DT_BOS:
1779                         if (gadget_is_superspeed(gadget) ||
1780                             gadget->lpm_capable) {
1781                                 value = bos_desc(cdev);
1782                                 value = min(w_length, (u16) value);
1783                         }
1784                         break;
1785                 case USB_DT_OTG:
1786                         if (gadget_is_otg(gadget)) {
1787                                 struct usb_configuration *config;
1788                                 int otg_desc_len = 0;
1789
1790                                 if (cdev->config)
1791                                         config = cdev->config;
1792                                 else
1793                                         config = list_first_entry(
1794                                                         &cdev->configs,
1795                                                 struct usb_configuration, list);
1796                                 if (!config)
1797                                         goto done;
1798
1799                                 if (gadget->otg_caps &&
1800                                         (gadget->otg_caps->otg_rev >= 0x0200))
1801                                         otg_desc_len += sizeof(
1802                                                 struct usb_otg20_descriptor);
1803                                 else
1804                                         otg_desc_len += sizeof(
1805                                                 struct usb_otg_descriptor);
1806
1807                                 value = min_t(int, w_length, otg_desc_len);
1808                                 memcpy(req->buf, config->descriptors[0], value);
1809                         }
1810                         break;
1811                 }
1812                 break;
1813
1814         /* any number of configs can work */
1815         case USB_REQ_SET_CONFIGURATION:
1816                 if (ctrl->bRequestType != 0)
1817                         goto unknown;
1818                 if (gadget_is_otg(gadget)) {
1819                         if (gadget->a_hnp_support)
1820                                 DBG(cdev, "HNP available\n");
1821                         else if (gadget->a_alt_hnp_support)
1822                                 DBG(cdev, "HNP on another port\n");
1823                         else
1824                                 VDBG(cdev, "HNP inactive\n");
1825                 }
1826                 spin_lock(&cdev->lock);
1827                 value = set_config(cdev, ctrl, w_value);
1828                 spin_unlock(&cdev->lock);
1829                 break;
1830         case USB_REQ_GET_CONFIGURATION:
1831                 if (ctrl->bRequestType != USB_DIR_IN)
1832                         goto unknown;
1833                 if (cdev->config)
1834                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1835                 else
1836                         *(u8 *)req->buf = 0;
1837                 value = min(w_length, (u16) 1);
1838                 break;
1839
1840         /* function drivers must handle get/set altsetting */
1841         case USB_REQ_SET_INTERFACE:
1842                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1843                         goto unknown;
1844                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1845                         break;
1846                 f = cdev->config->interface[intf];
1847                 if (!f)
1848                         break;
1849
1850                 /*
1851                  * If there's no get_alt() method, we know only altsetting zero
1852                  * works. There is no need to check if set_alt() is not NULL
1853                  * as we check this in usb_add_function().
1854                  */
1855                 if (w_value && !f->get_alt)
1856                         break;
1857
1858                 spin_lock(&cdev->lock);
1859                 value = f->set_alt(f, w_index, w_value);
1860                 if (value == USB_GADGET_DELAYED_STATUS) {
1861                         DBG(cdev,
1862                          "%s: interface %d (%s) requested delayed status\n",
1863                                         __func__, intf, f->name);
1864                         cdev->delayed_status++;
1865                         DBG(cdev, "delayed_status count %d\n",
1866                                         cdev->delayed_status);
1867                 }
1868                 spin_unlock(&cdev->lock);
1869                 break;
1870         case USB_REQ_GET_INTERFACE:
1871                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1872                         goto unknown;
1873                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1874                         break;
1875                 f = cdev->config->interface[intf];
1876                 if (!f)
1877                         break;
1878                 /* lots of interfaces only need altsetting zero... */
1879                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1880                 if (value < 0)
1881                         break;
1882                 *((u8 *)req->buf) = value;
1883                 value = min(w_length, (u16) 1);
1884                 break;
1885         case USB_REQ_GET_STATUS:
1886                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1887                                                 (w_index == OTG_STS_SELECTOR)) {
1888                         if (ctrl->bRequestType != (USB_DIR_IN |
1889                                                         USB_RECIP_DEVICE))
1890                                 goto unknown;
1891                         *((u8 *)req->buf) = gadget->host_request_flag;
1892                         value = 1;
1893                         break;
1894                 }
1895
1896                 /*
1897                  * USB 3.0 additions:
1898                  * Function driver should handle get_status request. If such cb
1899                  * wasn't supplied we respond with default value = 0
1900                  * Note: function driver should supply such cb only for the
1901                  * first interface of the function
1902                  */
1903                 if (!gadget_is_superspeed(gadget))
1904                         goto unknown;
1905                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1906                         goto unknown;
1907                 value = 2;      /* This is the length of the get_status reply */
1908                 put_unaligned_le16(0, req->buf);
1909                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1910                         break;
1911                 f = cdev->config->interface[intf];
1912                 if (!f)
1913                         break;
1914                 status = f->get_status ? f->get_status(f) : 0;
1915                 if (status < 0)
1916                         break;
1917                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1918                 break;
1919         /*
1920          * Function drivers should handle SetFeature/ClearFeature
1921          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1922          * only for the first interface of the function
1923          */
1924         case USB_REQ_CLEAR_FEATURE:
1925         case USB_REQ_SET_FEATURE:
1926                 if (!gadget_is_superspeed(gadget))
1927                         goto unknown;
1928                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1929                         goto unknown;
1930                 switch (w_value) {
1931                 case USB_INTRF_FUNC_SUSPEND:
1932                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1933                                 break;
1934                         f = cdev->config->interface[intf];
1935                         if (!f)
1936                                 break;
1937                         value = 0;
1938                         if (f->func_suspend)
1939                                 value = f->func_suspend(f, w_index >> 8);
1940                         if (value < 0) {
1941                                 ERROR(cdev,
1942                                       "func_suspend() returned error %d\n",
1943                                       value);
1944                                 value = 0;
1945                         }
1946                         break;
1947                 }
1948                 break;
1949         default:
1950 unknown:
1951                 /*
1952                  * OS descriptors handling
1953                  */
1954                 if (cdev->use_os_string && cdev->os_desc_config &&
1955                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1956                     ctrl->bRequest == cdev->b_vendor_code) {
1957                         struct usb_configuration        *os_desc_cfg;
1958                         u8                              *buf;
1959                         int                             interface;
1960                         int                             count = 0;
1961
1962                         req = cdev->os_desc_req;
1963                         req->context = cdev;
1964                         req->complete = composite_setup_complete;
1965                         buf = req->buf;
1966                         os_desc_cfg = cdev->os_desc_config;
1967                         w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1968                         memset(buf, 0, w_length);
1969                         buf[5] = 0x01;
1970                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1971                         case USB_RECIP_DEVICE:
1972                                 if (w_index != 0x4 || (w_value >> 8))
1973                                         break;
1974                                 buf[6] = w_index;
1975                                 /* Number of ext compat interfaces */
1976                                 count = count_ext_compat(os_desc_cfg);
1977                                 buf[8] = count;
1978                                 count *= 24; /* 24 B/ext compat desc */
1979                                 count += 16; /* header */
1980                                 put_unaligned_le32(count, buf);
1981                                 value = w_length;
1982                                 if (w_length > 0x10) {
1983                                         value = fill_ext_compat(os_desc_cfg, buf);
1984                                         value = min_t(u16, w_length, value);
1985                                 }
1986                                 break;
1987                         case USB_RECIP_INTERFACE:
1988                                 if (w_index != 0x5 || (w_value >> 8))
1989                                         break;
1990                                 interface = w_value & 0xFF;
1991                                 buf[6] = w_index;
1992                                 count = count_ext_prop(os_desc_cfg,
1993                                         interface);
1994                                 put_unaligned_le16(count, buf + 8);
1995                                 count = len_ext_prop(os_desc_cfg,
1996                                         interface);
1997                                 put_unaligned_le32(count, buf);
1998                                 value = w_length;
1999                                 if (w_length > 0x0A) {
2000                                         value = fill_ext_prop(os_desc_cfg,
2001                                                               interface, buf);
2002                                         if (value >= 0)
2003                                                 value = min_t(u16, w_length, value);
2004                                 }
2005                                 break;
2006                         }
2007
2008                         goto check_value;
2009                 }
2010
2011                 VDBG(cdev,
2012                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
2013                         ctrl->bRequestType, ctrl->bRequest,
2014                         w_value, w_index, w_length);
2015
2016                 /* functions always handle their interfaces and endpoints...
2017                  * punt other recipients (other, WUSB, ...) to the current
2018                  * configuration code.
2019                  */
2020                 if (cdev->config) {
2021                         list_for_each_entry(f, &cdev->config->functions, list)
2022                                 if (f->req_match &&
2023                                     f->req_match(f, ctrl, false))
2024                                         goto try_fun_setup;
2025                 } else {
2026                         struct usb_configuration *c;
2027                         list_for_each_entry(c, &cdev->configs, list)
2028                                 list_for_each_entry(f, &c->functions, list)
2029                                         if (f->req_match &&
2030                                             f->req_match(f, ctrl, true))
2031                                                 goto try_fun_setup;
2032                 }
2033                 f = NULL;
2034
2035                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
2036                 case USB_RECIP_INTERFACE:
2037                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2038                                 break;
2039                         f = cdev->config->interface[intf];
2040                         break;
2041
2042                 case USB_RECIP_ENDPOINT:
2043                         if (!cdev->config)
2044                                 break;
2045                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2046                         list_for_each_entry(f, &cdev->config->functions, list) {
2047                                 if (test_bit(endp, f->endpoints))
2048                                         break;
2049                         }
2050                         if (&f->list == &cdev->config->functions)
2051                                 f = NULL;
2052                         break;
2053                 }
2054 try_fun_setup:
2055                 if (f && f->setup)
2056                         value = f->setup(f, ctrl);
2057                 else {
2058                         struct usb_configuration        *c;
2059
2060                         c = cdev->config;
2061                         if (!c)
2062                                 goto done;
2063
2064                         /* try current config's setup */
2065                         if (c->setup) {
2066                                 value = c->setup(c, ctrl);
2067                                 goto done;
2068                         }
2069
2070                         /* try the only function in the current config */
2071                         if (!list_is_singular(&c->functions))
2072                                 goto done;
2073                         f = list_first_entry(&c->functions, struct usb_function,
2074                                              list);
2075                         if (f->setup)
2076                                 value = f->setup(f, ctrl);
2077                 }
2078
2079                 goto done;
2080         }
2081
2082 check_value:
2083         /* respond with data transfer before status phase? */
2084         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2085                 req->length = value;
2086                 req->context = cdev;
2087                 req->zero = value < w_length;
2088                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2089                 if (value < 0) {
2090                         DBG(cdev, "ep_queue --> %d\n", value);
2091                         req->status = 0;
2092                         composite_setup_complete(gadget->ep0, req);
2093                 }
2094         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2095                 WARN(cdev,
2096                         "%s: Delayed status not supported for w_length != 0",
2097                         __func__);
2098         }
2099
2100 done:
2101         /* device either stalls (value < 0) or reports success */
2102         return value;
2103 }
2104
2105 static void __composite_disconnect(struct usb_gadget *gadget)
2106 {
2107         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2108         unsigned long                   flags;
2109
2110         /* REVISIT:  should we have config and device level
2111          * disconnect callbacks?
2112          */
2113         spin_lock_irqsave(&cdev->lock, flags);
2114         cdev->suspended = 0;
2115         if (cdev->config)
2116                 reset_config(cdev);
2117         if (cdev->driver->disconnect)
2118                 cdev->driver->disconnect(cdev);
2119         spin_unlock_irqrestore(&cdev->lock, flags);
2120 }
2121
2122 void composite_disconnect(struct usb_gadget *gadget)
2123 {
2124         usb_gadget_vbus_draw(gadget, 0);
2125         __composite_disconnect(gadget);
2126 }
2127
2128 void composite_reset(struct usb_gadget *gadget)
2129 {
2130         /*
2131          * Section 1.4.13 Standard Downstream Port of the USB battery charging
2132          * specification v1.2 states that a device connected on a SDP shall only
2133          * draw at max 100mA while in a connected, but unconfigured state.
2134          */
2135         usb_gadget_vbus_draw(gadget, 100);
2136         __composite_disconnect(gadget);
2137 }
2138
2139 /*-------------------------------------------------------------------------*/
2140
2141 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2142                               char *buf)
2143 {
2144         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2145         struct usb_composite_dev *cdev = get_gadget_data(gadget);
2146
2147         return sprintf(buf, "%d\n", cdev->suspended);
2148 }
2149 static DEVICE_ATTR_RO(suspended);
2150
2151 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2152 {
2153         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2154         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2155         struct usb_string               *dev_str = gstr->strings;
2156
2157         /* composite_disconnect() must already have been called
2158          * by the underlying peripheral controller driver!
2159          * so there's no i/o concurrency that could affect the
2160          * state protected by cdev->lock.
2161          */
2162         WARN_ON(cdev->config);
2163
2164         while (!list_empty(&cdev->configs)) {
2165                 struct usb_configuration        *c;
2166                 c = list_first_entry(&cdev->configs,
2167                                 struct usb_configuration, list);
2168                 remove_config(cdev, c);
2169         }
2170         if (cdev->driver->unbind && unbind_driver)
2171                 cdev->driver->unbind(cdev);
2172
2173         composite_dev_cleanup(cdev);
2174
2175         if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2176                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2177
2178         kfree(cdev->def_manufacturer);
2179         kfree(cdev);
2180         set_gadget_data(gadget, NULL);
2181 }
2182
2183 static void composite_unbind(struct usb_gadget *gadget)
2184 {
2185         __composite_unbind(gadget, true);
2186 }
2187
2188 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2189                 const struct usb_device_descriptor *old)
2190 {
2191         __le16 idVendor;
2192         __le16 idProduct;
2193         __le16 bcdDevice;
2194         u8 iSerialNumber;
2195         u8 iManufacturer;
2196         u8 iProduct;
2197
2198         /*
2199          * these variables may have been set in
2200          * usb_composite_overwrite_options()
2201          */
2202         idVendor = new->idVendor;
2203         idProduct = new->idProduct;
2204         bcdDevice = new->bcdDevice;
2205         iSerialNumber = new->iSerialNumber;
2206         iManufacturer = new->iManufacturer;
2207         iProduct = new->iProduct;
2208
2209         *new = *old;
2210         if (idVendor)
2211                 new->idVendor = idVendor;
2212         if (idProduct)
2213                 new->idProduct = idProduct;
2214         if (bcdDevice)
2215                 new->bcdDevice = bcdDevice;
2216         else
2217                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2218         if (iSerialNumber)
2219                 new->iSerialNumber = iSerialNumber;
2220         if (iManufacturer)
2221                 new->iManufacturer = iManufacturer;
2222         if (iProduct)
2223                 new->iProduct = iProduct;
2224 }
2225
2226 int composite_dev_prepare(struct usb_composite_driver *composite,
2227                 struct usb_composite_dev *cdev)
2228 {
2229         struct usb_gadget *gadget = cdev->gadget;
2230         int ret = -ENOMEM;
2231
2232         /* preallocate control response and buffer */
2233         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2234         if (!cdev->req)
2235                 return -ENOMEM;
2236
2237         cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2238         if (!cdev->req->buf)
2239                 goto fail;
2240
2241         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2242         if (ret)
2243                 goto fail_dev;
2244
2245         cdev->req->complete = composite_setup_complete;
2246         cdev->req->context = cdev;
2247         gadget->ep0->driver_data = cdev;
2248
2249         cdev->driver = composite;
2250
2251         /*
2252          * As per USB compliance update, a device that is actively drawing
2253          * more than 100mA from USB must report itself as bus-powered in
2254          * the GetStatus(DEVICE) call.
2255          */
2256         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2257                 usb_gadget_set_selfpowered(gadget);
2258
2259         /* interface and string IDs start at zero via kzalloc.
2260          * we force endpoints to start unassigned; few controller
2261          * drivers will zero ep->driver_data.
2262          */
2263         usb_ep_autoconfig_reset(gadget);
2264         return 0;
2265 fail_dev:
2266         kfree(cdev->req->buf);
2267 fail:
2268         usb_ep_free_request(gadget->ep0, cdev->req);
2269         cdev->req = NULL;
2270         return ret;
2271 }
2272
2273 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2274                                   struct usb_ep *ep0)
2275 {
2276         int ret = 0;
2277
2278         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2279         if (!cdev->os_desc_req) {
2280                 ret = -ENOMEM;
2281                 goto end;
2282         }
2283
2284         cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2285                                          GFP_KERNEL);
2286         if (!cdev->os_desc_req->buf) {
2287                 ret = -ENOMEM;
2288                 usb_ep_free_request(ep0, cdev->os_desc_req);
2289                 goto end;
2290         }
2291         cdev->os_desc_req->context = cdev;
2292         cdev->os_desc_req->complete = composite_setup_complete;
2293 end:
2294         return ret;
2295 }
2296
2297 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2298 {
2299         struct usb_gadget_string_container *uc, *tmp;
2300         struct usb_ep                      *ep, *tmp_ep;
2301
2302         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2303                 list_del(&uc->list);
2304                 kfree(uc);
2305         }
2306         if (cdev->os_desc_req) {
2307                 if (cdev->os_desc_pending)
2308                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2309
2310                 kfree(cdev->os_desc_req->buf);
2311                 cdev->os_desc_req->buf = NULL;
2312                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2313                 cdev->os_desc_req = NULL;
2314         }
2315         if (cdev->req) {
2316                 if (cdev->setup_pending)
2317                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2318
2319                 kfree(cdev->req->buf);
2320                 cdev->req->buf = NULL;
2321                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2322                 cdev->req = NULL;
2323         }
2324         cdev->next_string_id = 0;
2325         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2326
2327         /*
2328          * Some UDC backends have a dynamic EP allocation scheme.
2329          *
2330          * In that case, the dispose() callback is used to notify the
2331          * backend that the EPs are no longer in use.
2332          *
2333          * Note: The UDC backend can remove the EP from the ep_list as
2334          *       a result, so we need to use the _safe list iterator.
2335          */
2336         list_for_each_entry_safe(ep, tmp_ep,
2337                                  &cdev->gadget->ep_list, ep_list) {
2338                 if (ep->ops->dispose)
2339                         ep->ops->dispose(ep);
2340         }
2341 }
2342
2343 static int composite_bind(struct usb_gadget *gadget,
2344                 struct usb_gadget_driver *gdriver)
2345 {
2346         struct usb_composite_dev        *cdev;
2347         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2348         int                             status = -ENOMEM;
2349
2350         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2351         if (!cdev)
2352                 return status;
2353
2354         spin_lock_init(&cdev->lock);
2355         cdev->gadget = gadget;
2356         set_gadget_data(gadget, cdev);
2357         INIT_LIST_HEAD(&cdev->configs);
2358         INIT_LIST_HEAD(&cdev->gstrings);
2359
2360         status = composite_dev_prepare(composite, cdev);
2361         if (status)
2362                 goto fail;
2363
2364         /* composite gadget needs to assign strings for whole device (like
2365          * serial number), register function drivers, potentially update
2366          * power state and consumption, etc
2367          */
2368         status = composite->bind(cdev);
2369         if (status < 0)
2370                 goto fail;
2371
2372         if (cdev->use_os_string) {
2373                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2374                 if (status)
2375                         goto fail;
2376         }
2377
2378         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2379
2380         /* has userspace failed to provide a serial number? */
2381         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2382                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2383
2384         INFO(cdev, "%s ready\n", composite->name);
2385         return 0;
2386
2387 fail:
2388         __composite_unbind(gadget, false);
2389         return status;
2390 }
2391
2392 /*-------------------------------------------------------------------------*/
2393
2394 void composite_suspend(struct usb_gadget *gadget)
2395 {
2396         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2397         struct usb_function             *f;
2398
2399         /* REVISIT:  should we have config level
2400          * suspend/resume callbacks?
2401          */
2402         DBG(cdev, "suspend\n");
2403         if (cdev->config) {
2404                 list_for_each_entry(f, &cdev->config->functions, list) {
2405                         if (f->suspend)
2406                                 f->suspend(f);
2407                 }
2408         }
2409         if (cdev->driver->suspend)
2410                 cdev->driver->suspend(cdev);
2411
2412         cdev->suspended = 1;
2413
2414         usb_gadget_set_selfpowered(gadget);
2415         usb_gadget_vbus_draw(gadget, 2);
2416 }
2417
2418 void composite_resume(struct usb_gadget *gadget)
2419 {
2420         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2421         struct usb_function             *f;
2422         unsigned                        maxpower;
2423
2424         /* REVISIT:  should we have config level
2425          * suspend/resume callbacks?
2426          */
2427         DBG(cdev, "resume\n");
2428         if (cdev->driver->resume)
2429                 cdev->driver->resume(cdev);
2430         if (cdev->config) {
2431                 list_for_each_entry(f, &cdev->config->functions, list) {
2432                         if (f->resume)
2433                                 f->resume(f);
2434                 }
2435
2436                 maxpower = cdev->config->MaxPower ?
2437                         cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2438                 if (gadget->speed < USB_SPEED_SUPER)
2439                         maxpower = min(maxpower, 500U);
2440                 else
2441                         maxpower = min(maxpower, 900U);
2442
2443                 if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2444                         usb_gadget_clear_selfpowered(gadget);
2445
2446                 usb_gadget_vbus_draw(gadget, maxpower);
2447         }
2448
2449         cdev->suspended = 0;
2450 }
2451
2452 /*-------------------------------------------------------------------------*/
2453
2454 static const struct usb_gadget_driver composite_driver_template = {
2455         .bind           = composite_bind,
2456         .unbind         = composite_unbind,
2457
2458         .setup          = composite_setup,
2459         .reset          = composite_reset,
2460         .disconnect     = composite_disconnect,
2461
2462         .suspend        = composite_suspend,
2463         .resume         = composite_resume,
2464
2465         .driver = {
2466                 .owner          = THIS_MODULE,
2467         },
2468 };
2469
2470 /**
2471  * usb_composite_probe() - register a composite driver
2472  * @driver: the driver to register
2473  *
2474  * Context: single threaded during gadget setup
2475  *
2476  * This function is used to register drivers using the composite driver
2477  * framework.  The return value is zero, or a negative errno value.
2478  * Those values normally come from the driver's @bind method, which does
2479  * all the work of setting up the driver to match the hardware.
2480  *
2481  * On successful return, the gadget is ready to respond to requests from
2482  * the host, unless one of its components invokes usb_gadget_disconnect()
2483  * while it was binding.  That would usually be done in order to wait for
2484  * some userspace participation.
2485  */
2486 int usb_composite_probe(struct usb_composite_driver *driver)
2487 {
2488         struct usb_gadget_driver *gadget_driver;
2489
2490         if (!driver || !driver->dev || !driver->bind)
2491                 return -EINVAL;
2492
2493         if (!driver->name)
2494                 driver->name = "composite";
2495
2496         driver->gadget_driver = composite_driver_template;
2497         gadget_driver = &driver->gadget_driver;
2498
2499         gadget_driver->function =  (char *) driver->name;
2500         gadget_driver->driver.name = driver->name;
2501         gadget_driver->max_speed = driver->max_speed;
2502
2503         return usb_gadget_probe_driver(gadget_driver);
2504 }
2505 EXPORT_SYMBOL_GPL(usb_composite_probe);
2506
2507 /**
2508  * usb_composite_unregister() - unregister a composite driver
2509  * @driver: the driver to unregister
2510  *
2511  * This function is used to unregister drivers using the composite
2512  * driver framework.
2513  */
2514 void usb_composite_unregister(struct usb_composite_driver *driver)
2515 {
2516         usb_gadget_unregister_driver(&driver->gadget_driver);
2517 }
2518 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2519
2520 /**
2521  * usb_composite_setup_continue() - Continue with the control transfer
2522  * @cdev: the composite device who's control transfer was kept waiting
2523  *
2524  * This function must be called by the USB function driver to continue
2525  * with the control transfer's data/status stage in case it had requested to
2526  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2527  * can request the composite framework to delay the setup request's data/status
2528  * stages by returning USB_GADGET_DELAYED_STATUS.
2529  */
2530 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2531 {
2532         int                     value;
2533         struct usb_request      *req = cdev->req;
2534         unsigned long           flags;
2535
2536         DBG(cdev, "%s\n", __func__);
2537         spin_lock_irqsave(&cdev->lock, flags);
2538
2539         if (cdev->delayed_status == 0) {
2540                 WARN(cdev, "%s: Unexpected call\n", __func__);
2541
2542         } else if (--cdev->delayed_status == 0) {
2543                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2544                 req->length = 0;
2545                 req->context = cdev;
2546                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2547                 if (value < 0) {
2548                         DBG(cdev, "ep_queue --> %d\n", value);
2549                         req->status = 0;
2550                         composite_setup_complete(cdev->gadget->ep0, req);
2551                 }
2552         }
2553
2554         spin_unlock_irqrestore(&cdev->lock, flags);
2555 }
2556 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2557
2558 static char *composite_default_mfr(struct usb_gadget *gadget)
2559 {
2560         return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2561                          init_utsname()->release, gadget->name);
2562 }
2563
2564 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2565                 struct usb_composite_overwrite *covr)
2566 {
2567         struct usb_device_descriptor    *desc = &cdev->desc;
2568         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2569         struct usb_string               *dev_str = gstr->strings;
2570
2571         if (covr->idVendor)
2572                 desc->idVendor = cpu_to_le16(covr->idVendor);
2573
2574         if (covr->idProduct)
2575                 desc->idProduct = cpu_to_le16(covr->idProduct);
2576
2577         if (covr->bcdDevice)
2578                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2579
2580         if (covr->serial_number) {
2581                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2582                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2583         }
2584         if (covr->manufacturer) {
2585                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2586                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2587
2588         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2589                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2590                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2591                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2592         }
2593
2594         if (covr->product) {
2595                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2596                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2597         }
2598 }
2599 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2600
2601 MODULE_LICENSE("GPL");
2602 MODULE_AUTHOR("David Brownell");