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, *iter;
 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(iter, &cdev->configs, list) {
 873                         if (iter->bConfigurationValue != number)
 874                                 continue;
 875                         /*
 876                          * We disable the FDs of the previous
 877                          * configuration only if the new configuration
 878                          * is a valid one
 879                          */
 880                         if (cdev->config)
 881                                 reset_config(cdev);
 882                         c = iter;
 883                         result = 0;
 884                         break;
 885                 }
 886                 if (result < 0)
 887                         goto done;
 888         } else { /* Zero configuration value - need to reset the config */
 889                 if (cdev->config)
 890                         reset_config(cdev);
 891                 result = 0;
 892         }
 893
 894         DBG(cdev, "%s config #%d: %s\n",
 895             usb_speed_string(gadget->speed),
 896             number, c ? c->label : "unconfigured");
 897
 898         if (!c)
 899                 goto done;
 900
 901         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 902         cdev->config = c;
 903
 904         /* Initialize all interfaces by setting them to altsetting zero. */
 905         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 906                 struct usb_function     *f = c->interface[tmp];
 907                 struct usb_descriptor_header **descriptors;
 908
 909                 if (!f)
 910                         break;
 911
 912                 /*
 913                  * Record which endpoints are used by the function. This is used
 914                  * to dispatch control requests targeted at that endpoint to the
 915                  * function's setup callback instead of the current
 916                  * configuration's setup callback.
 917                  */
 918                 descriptors = function_descriptors(f, gadget->speed);
 919
 920                 for (; *descriptors; ++descriptors) {
 921                         struct usb_endpoint_descriptor *ep;
 922                         int addr;
 923
 924                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 925                                 continue;
 926
 927                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 928                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 929                              |  (ep->bEndpointAddress & 0x0f);
 930                         set_bit(addr, f->endpoints);
 931                 }
 932
 933                 result = f->set_alt(f, tmp, 0);
 934                 if (result < 0) {
 935                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 936                                         tmp, f->name, f, result);
 937
 938                         reset_config(cdev);
 939                         goto done;
 940                 }
 941
 942                 if (result == USB_GADGET_DELAYED_STATUS) {
 943                         DBG(cdev,
 944                          "%s: interface %d (%s) requested delayed status\n",
 945                                         __func__, tmp, f->name);
 946                         cdev->delayed_status++;
 947                         DBG(cdev, "delayed_status count %d\n",
 948                                         cdev->delayed_status);
 949                 }
 950         }
 951
 952         /* when we return, be sure our power usage is valid */
 953         if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 954                 power = c->MaxPower;
 955         else
 956                 power = CONFIG_USB_GADGET_VBUS_DRAW;
 957
 958         if (gadget->speed < USB_SPEED_SUPER)
 959                 power = min(power, 500U);
 960         else
 961                 power = min(power, 900U);
 962 done:
 963         if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
 964                 usb_gadget_set_selfpowered(gadget);
 965         else
 966                 usb_gadget_clear_selfpowered(gadget);
 967
 968         usb_gadget_vbus_draw(gadget, power);
 969         if (result >= 0 && cdev->delayed_status)
 970                 result = USB_GADGET_DELAYED_STATUS;
 971         return result;
 972 }
 973
 974 int usb_add_config_only(struct usb_composite_dev *cdev,
 975                 struct usb_configuration *config)
 976 {
 977         struct usb_configuration *c;
 978
 979         if (!config->bConfigurationValue)
 980                 return -EINVAL;
 981
 982         /* Prevent duplicate configuration identifiers */
 983         list_for_each_entry(c, &cdev->configs, list) {
 984                 if (c->bConfigurationValue == config->bConfigurationValue)
 985                         return -EBUSY;
 986         }
 987
 988         config->cdev = cdev;
 989         list_add_tail(&config->list, &cdev->configs);
 990
 991         INIT_LIST_HEAD(&config->functions);
 992         config->next_interface_id = 0;
 993         memset(config->interface, 0, sizeof(config->interface));
 994
 995         return 0;
 996 }
 997 EXPORT_SYMBOL_GPL(usb_add_config_only);
 998
 999 /**
1000  * usb_add_config() - add a configuration to a device.
1001  * @cdev: wraps the USB gadget
1002  * @config: the configuration, with bConfigurationValue assigned
1003  * @bind: the configuration's bind function
1004  * Context: single threaded during gadget setup
1005  *
1006  * One of the main tasks of a composite @bind() routine is to
1007  * add each of the configurations it supports, using this routine.
1008  *
1009  * This function returns the value of the configuration's @bind(), which
1010  * is zero for success else a negative errno value.  Binding configurations
1011  * assigns global resources including string IDs, and per-configuration
1012  * resources such as interface IDs and endpoints.
1013  */
1014 int usb_add_config(struct usb_composite_dev *cdev,
1015                 struct usb_configuration *config,
1016                 int (*bind)(struct usb_configuration *))
1017 {
1018         int                             status = -EINVAL;
1019
1020         if (!bind)
1021                 goto done;
1022
1023         DBG(cdev, "adding config #%u '%s'/%p\n",
1024                         config->bConfigurationValue,
1025                         config->label, config);
1026
1027         status = usb_add_config_only(cdev, config);
1028         if (status)
1029                 goto done;
1030
1031         status = bind(config);
1032         if (status < 0) {
1033                 while (!list_empty(&config->functions)) {
1034                         struct usb_function             *f;
1035
1036                         f = list_first_entry(&config->functions,
1037                                         struct usb_function, list);
1038                         list_del(&f->list);
1039                         if (f->unbind) {
1040                                 DBG(cdev, "unbind function '%s'/%p\n",
1041                                         f->name, f);
1042                                 f->unbind(config, f);
1043                                 /* may free memory for "f" */
1044                         }
1045                 }
1046                 list_del(&config->list);
1047                 config->cdev = NULL;
1048         } else {
1049                 unsigned        i;
1050
1051                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1052                         config->bConfigurationValue, config,
1053                         config->superspeed_plus ? " superplus" : "",
1054                         config->superspeed ? " super" : "",
1055                         config->highspeed ? " high" : "",
1056                         config->fullspeed
1057                                 ? (gadget_is_dualspeed(cdev->gadget)
1058                                         ? " full"
1059                                         : " full/low")
1060                                 : "");
1061
1062                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1063                         struct usb_function     *f = config->interface[i];
1064
1065                         if (!f)
1066                                 continue;
1067                         DBG(cdev, "  interface %d = %s/%p\n",
1068                                 i, f->name, f);
1069                 }
1070         }
1071
1072         /* set_alt(), or next bind(), sets up ep->claimed as needed */
1073         usb_ep_autoconfig_reset(cdev->gadget);
1074
1075 done:
1076         if (status)
1077                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1078                                 config->bConfigurationValue, status);
1079         return status;
1080 }
1081 EXPORT_SYMBOL_GPL(usb_add_config);
1082
1083 static void remove_config(struct usb_composite_dev *cdev,
1084                               struct usb_configuration *config)
1085 {
1086         while (!list_empty(&config->functions)) {
1087                 struct usb_function             *f;
1088
1089                 f = list_first_entry(&config->functions,
1090                                 struct usb_function, list);
1091
1092                 usb_remove_function(config, f);
1093         }
1094         list_del(&config->list);
1095         if (config->unbind) {
1096                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1097                 config->unbind(config);
1098                         /* may free memory for "c" */
1099         }
1100 }
1101
1102 /**
1103  * usb_remove_config() - remove a configuration from a device.
1104  * @cdev: wraps the USB gadget
1105  * @config: the configuration
1106  *
1107  * Drivers must call usb_gadget_disconnect before calling this function
1108  * to disconnect the device from the host and make sure the host will not
1109  * try to enumerate the device while we are changing the config list.
1110  */
1111 void usb_remove_config(struct usb_composite_dev *cdev,
1112                       struct usb_configuration *config)
1113 {
1114         unsigned long flags;
1115
1116         spin_lock_irqsave(&cdev->lock, flags);
1117
1118         if (cdev->config == config)
1119                 reset_config(cdev);
1120
1121         spin_unlock_irqrestore(&cdev->lock, flags);
1122
1123         remove_config(cdev, config);
1124 }
1125
1126 /*-------------------------------------------------------------------------*/
1127
1128 /* We support strings in multiple languages ... string descriptor zero
1129  * says which languages are supported.  The typical case will be that
1130  * only one language (probably English) is used, with i18n handled on
1131  * the host side.
1132  */
1133
1134 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1135 {
1136         const struct usb_gadget_strings *s;
1137         __le16                          language;
1138         __le16                          *tmp;
1139
1140         while (*sp) {
1141                 s = *sp;
1142                 language = cpu_to_le16(s->language);
1143                 for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1144                         if (*tmp == language)
1145                                 goto repeat;
1146                 }
1147                 *tmp++ = language;
1148 repeat:
1149                 sp++;
1150         }
1151 }
1152
1153 static int lookup_string(
1154         struct usb_gadget_strings       **sp,
1155         void                            *buf,
1156         u16                             language,
1157         int                             id
1158 )
1159 {
1160         struct usb_gadget_strings       *s;
1161         int                             value;
1162
1163         while (*sp) {
1164                 s = *sp++;
1165                 if (s->language != language)
1166                         continue;
1167                 value = usb_gadget_get_string(s, id, buf);
1168                 if (value > 0)
1169                         return value;
1170         }
1171         return -EINVAL;
1172 }
1173
1174 static int get_string(struct usb_composite_dev *cdev,
1175                 void *buf, u16 language, int id)
1176 {
1177         struct usb_composite_driver     *composite = cdev->driver;
1178         struct usb_gadget_string_container *uc;
1179         struct usb_configuration        *c;
1180         struct usb_function             *f;
1181         int                             len;
1182
1183         /* Yes, not only is USB's i18n support probably more than most
1184          * folk will ever care about ... also, it's all supported here.
1185          * (Except for UTF8 support for Unicode's "Astral Planes".)
1186          */
1187
1188         /* 0 == report all available language codes */
1189         if (id == 0) {
1190                 struct usb_string_descriptor    *s = buf;
1191                 struct usb_gadget_strings       **sp;
1192
1193                 memset(s, 0, 256);
1194                 s->bDescriptorType = USB_DT_STRING;
1195
1196                 sp = composite->strings;
1197                 if (sp)
1198                         collect_langs(sp, s->wData);
1199
1200                 list_for_each_entry(c, &cdev->configs, list) {
1201                         sp = c->strings;
1202                         if (sp)
1203                                 collect_langs(sp, s->wData);
1204
1205                         list_for_each_entry(f, &c->functions, list) {
1206                                 sp = f->strings;
1207                                 if (sp)
1208                                         collect_langs(sp, s->wData);
1209                         }
1210                 }
1211                 list_for_each_entry(uc, &cdev->gstrings, list) {
1212                         struct usb_gadget_strings **sp;
1213
1214                         sp = get_containers_gs(uc);
1215                         collect_langs(sp, s->wData);
1216                 }
1217
1218                 for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1219                         continue;
1220                 if (!len)
1221                         return -EINVAL;
1222
1223                 s->bLength = 2 * (len + 1);
1224                 return s->bLength;
1225         }
1226
1227         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1228                 struct usb_os_string *b = buf;
1229                 b->bLength = sizeof(*b);
1230                 b->bDescriptorType = USB_DT_STRING;
1231                 compiletime_assert(
1232                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1233                         "qwSignature size must be equal to qw_sign");
1234                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1235                 b->bMS_VendorCode = cdev->b_vendor_code;
1236                 b->bPad = 0;
1237                 return sizeof(*b);
1238         }
1239
1240         list_for_each_entry(uc, &cdev->gstrings, list) {
1241                 struct usb_gadget_strings **sp;
1242
1243                 sp = get_containers_gs(uc);
1244                 len = lookup_string(sp, buf, language, id);
1245                 if (len > 0)
1246                         return len;
1247         }
1248
1249         /* String IDs are device-scoped, so we look up each string
1250          * table we're told about.  These lookups are infrequent;
1251          * simpler-is-better here.
1252          */
1253         if (composite->strings) {
1254                 len = lookup_string(composite->strings, buf, language, id);
1255                 if (len > 0)
1256                         return len;
1257         }
1258         list_for_each_entry(c, &cdev->configs, list) {
1259                 if (c->strings) {
1260                         len = lookup_string(c->strings, buf, language, id);
1261                         if (len > 0)
1262                                 return len;
1263                 }
1264                 list_for_each_entry(f, &c->functions, list) {
1265                         if (!f->strings)
1266                                 continue;
1267                         len = lookup_string(f->strings, buf, language, id);
1268                         if (len > 0)
1269                                 return len;
1270                 }
1271         }
1272         return -EINVAL;
1273 }
1274
1275 /**
1276  * usb_string_id() - allocate an unused string ID
1277  * @cdev: the device whose string descriptor IDs are being allocated
1278  * Context: single threaded during gadget setup
1279  *
1280  * @usb_string_id() is called from bind() callbacks to allocate
1281  * string IDs.  Drivers for functions, configurations, or gadgets will
1282  * then store that ID in the appropriate descriptors and string table.
1283  *
1284  * All string identifier should be allocated using this,
1285  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1286  * that for example different functions don't wrongly assign different
1287  * meanings to the same identifier.
1288  */
1289 int usb_string_id(struct usb_composite_dev *cdev)
1290 {
1291         if (cdev->next_string_id < 254) {
1292                 /* string id 0 is reserved by USB spec for list of
1293                  * supported languages */
1294                 /* 255 reserved as well? -- mina86 */
1295                 cdev->next_string_id++;
1296                 return cdev->next_string_id;
1297         }
1298         return -ENODEV;
1299 }
1300 EXPORT_SYMBOL_GPL(usb_string_id);
1301
1302 /**
1303  * usb_string_ids_tab() - allocate unused string IDs in batch
1304  * @cdev: the device whose string descriptor IDs are being allocated
1305  * @str: an array of usb_string objects to assign numbers to
1306  * Context: single threaded during gadget setup
1307  *
1308  * @usb_string_ids() is called from bind() callbacks to allocate
1309  * string IDs.  Drivers for functions, configurations, or gadgets will
1310  * then copy IDs from the string table to the appropriate descriptors
1311  * and string table for other languages.
1312  *
1313  * All string identifier should be allocated using this,
1314  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1315  * example different functions don't wrongly assign different meanings
1316  * to the same identifier.
1317  */
1318 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1319 {
1320         int next = cdev->next_string_id;
1321
1322         for (; str->s; ++str) {
1323                 if (unlikely(next >= 254))
1324                         return -ENODEV;
1325                 str->id = ++next;
1326         }
1327
1328         cdev->next_string_id = next;
1329
1330         return 0;
1331 }
1332 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1333
1334 static struct usb_gadget_string_container *copy_gadget_strings(
1335                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1336                 unsigned n_strings)
1337 {
1338         struct usb_gadget_string_container *uc;
1339         struct usb_gadget_strings **gs_array;
1340         struct usb_gadget_strings *gs;
1341         struct usb_string *s;
1342         unsigned mem;
1343         unsigned n_gs;
1344         unsigned n_s;
1345         void *stash;
1346
1347         mem = sizeof(*uc);
1348         mem += sizeof(void *) * (n_gstrings + 1);
1349         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1350         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1351         uc = kmalloc(mem, GFP_KERNEL);
1352         if (!uc)
1353                 return ERR_PTR(-ENOMEM);
1354         gs_array = get_containers_gs(uc);
1355         stash = uc->stash;
1356         stash += sizeof(void *) * (n_gstrings + 1);
1357         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1358                 struct usb_string *org_s;
1359
1360                 gs_array[n_gs] = stash;
1361                 gs = gs_array[n_gs];
1362                 stash += sizeof(struct usb_gadget_strings);
1363                 gs->language = sp[n_gs]->language;
1364                 gs->strings = stash;
1365                 org_s = sp[n_gs]->strings;
1366
1367                 for (n_s = 0; n_s < n_strings; n_s++) {
1368                         s = stash;
1369                         stash += sizeof(struct usb_string);
1370                         if (org_s->s)
1371                                 s->s = org_s->s;
1372                         else
1373                                 s->s = "";
1374                         org_s++;
1375                 }
1376                 s = stash;
1377                 s->s = NULL;
1378                 stash += sizeof(struct usb_string);
1379
1380         }
1381         gs_array[n_gs] = NULL;
1382         return uc;
1383 }
1384
1385 /**
1386  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1387  * @cdev: the device whose string descriptor IDs are being allocated
1388  * and attached.
1389  * @sp: an array of usb_gadget_strings to attach.
1390  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1391  *
1392  * This function will create a deep copy of usb_gadget_strings and usb_string
1393  * and attach it to the cdev. The actual string (usb_string.s) will not be
1394  * copied but only a referenced will be made. The struct usb_gadget_strings
1395  * array may contain multiple languages and should be NULL terminated.
1396  * The ->language pointer of each struct usb_gadget_strings has to contain the
1397  * same amount of entries.
1398  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1399  * usb_string entry of es-ES contains the translation of the first usb_string
1400  * entry of en-US. Therefore both entries become the same id assign.
1401  */
1402 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1403                 struct usb_gadget_strings **sp, unsigned n_strings)
1404 {
1405         struct usb_gadget_string_container *uc;
1406         struct usb_gadget_strings **n_gs;
1407         unsigned n_gstrings = 0;
1408         unsigned i;
1409         int ret;
1410
1411         for (i = 0; sp[i]; i++)
1412                 n_gstrings++;
1413
1414         if (!n_gstrings)
1415                 return ERR_PTR(-EINVAL);
1416
1417         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1418         if (IS_ERR(uc))
1419                 return ERR_CAST(uc);
1420
1421         n_gs = get_containers_gs(uc);
1422         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1423         if (ret)
1424                 goto err;
1425
1426         for (i = 1; i < n_gstrings; i++) {
1427                 struct usb_string *m_s;
1428                 struct usb_string *s;
1429                 unsigned n;
1430
1431                 m_s = n_gs[0]->strings;
1432                 s = n_gs[i]->strings;
1433                 for (n = 0; n < n_strings; n++) {
1434                         s->id = m_s->id;
1435                         s++;
1436                         m_s++;
1437                 }
1438         }
1439         list_add_tail(&uc->list, &cdev->gstrings);
1440         return n_gs[0]->strings;
1441 err:
1442         kfree(uc);
1443         return ERR_PTR(ret);
1444 }
1445 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1446
1447 /**
1448  * usb_string_ids_n() - allocate unused string IDs in batch
1449  * @c: the device whose string descriptor IDs are being allocated
1450  * @n: number of string IDs to allocate
1451  * Context: single threaded during gadget setup
1452  *
1453  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1454  * valid IDs.  At least provided that @n is non-zero because if it
1455  * is, returns last requested ID which is now very useful information.
1456  *
1457  * @usb_string_ids_n() is called from bind() callbacks to allocate
1458  * string IDs.  Drivers for functions, configurations, or gadgets will
1459  * then store that ID in the appropriate descriptors and string table.
1460  *
1461  * All string identifier should be allocated using this,
1462  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1463  * example different functions don't wrongly assign different meanings
1464  * to the same identifier.
1465  */
1466 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1467 {
1468         unsigned next = c->next_string_id;
1469         if (unlikely(n > 254 || (unsigned)next + n > 254))
1470                 return -ENODEV;
1471         c->next_string_id += n;
1472         return next + 1;
1473 }
1474 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1475
1476 /*-------------------------------------------------------------------------*/
1477
1478 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1479 {
1480         struct usb_composite_dev *cdev;
1481
1482         if (req->status || req->actual != req->length)
1483                 DBG((struct usb_composite_dev *) ep->driver_data,
1484                                 "setup complete --> %d, %d/%d\n",
1485                                 req->status, req->actual, req->length);
1486
1487         /*
1488          * REVIST The same ep0 requests are shared with function drivers
1489          * so they don't have to maintain the same ->complete() stubs.
1490          *
1491          * Because of that, we need to check for the validity of ->context
1492          * here, even though we know we've set it to something useful.
1493          */
1494         if (!req->context)
1495                 return;
1496
1497         cdev = req->context;
1498
1499         if (cdev->req == req)
1500                 cdev->setup_pending = false;
1501         else if (cdev->os_desc_req == req)
1502                 cdev->os_desc_pending = false;
1503         else
1504                 WARN(1, "unknown request %p\n", req);
1505 }
1506
1507 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1508                 struct usb_request *req, gfp_t gfp_flags)
1509 {
1510         int ret;
1511
1512         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1513         if (ret == 0) {
1514                 if (cdev->req == req)
1515                         cdev->setup_pending = true;
1516                 else if (cdev->os_desc_req == req)
1517                         cdev->os_desc_pending = true;
1518                 else
1519                         WARN(1, "unknown request %p\n", req);
1520         }
1521
1522         return ret;
1523 }
1524
1525 static int count_ext_compat(struct usb_configuration *c)
1526 {
1527         int i, res;
1528
1529         res = 0;
1530         for (i = 0; i < c->next_interface_id; ++i) {
1531                 struct usb_function *f;
1532                 int j;
1533
1534                 f = c->interface[i];
1535                 for (j = 0; j < f->os_desc_n; ++j) {
1536                         struct usb_os_desc *d;
1537
1538                         if (i != f->os_desc_table[j].if_id)
1539                                 continue;
1540                         d = f->os_desc_table[j].os_desc;
1541                         if (d && d->ext_compat_id)
1542                                 ++res;
1543                 }
1544         }
1545         BUG_ON(res > 255);
1546         return res;
1547 }
1548
1549 static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1550 {
1551         int i, count;
1552
1553         count = 16;
1554         buf += 16;
1555         for (i = 0; i < c->next_interface_id; ++i) {
1556                 struct usb_function *f;
1557                 int j;
1558
1559                 f = c->interface[i];
1560                 for (j = 0; j < f->os_desc_n; ++j) {
1561                         struct usb_os_desc *d;
1562
1563                         if (i != f->os_desc_table[j].if_id)
1564                                 continue;
1565                         d = f->os_desc_table[j].os_desc;
1566                         if (d && d->ext_compat_id) {
1567                                 *buf++ = i;
1568                                 *buf++ = 0x01;
1569                                 memcpy(buf, d->ext_compat_id, 16);
1570                                 buf += 22;
1571                         } else {
1572                                 ++buf;
1573                                 *buf = 0x01;
1574                                 buf += 23;
1575                         }
1576                         count += 24;
1577                         if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1578                                 return count;
1579                 }
1580         }
1581
1582         return count;
1583 }
1584
1585 static int count_ext_prop(struct usb_configuration *c, int interface)
1586 {
1587         struct usb_function *f;
1588         int j;
1589
1590         f = c->interface[interface];
1591         for (j = 0; j < f->os_desc_n; ++j) {
1592                 struct usb_os_desc *d;
1593
1594                 if (interface != f->os_desc_table[j].if_id)
1595                         continue;
1596                 d = f->os_desc_table[j].os_desc;
1597                 if (d && d->ext_compat_id)
1598                         return d->ext_prop_count;
1599         }
1600         return 0;
1601 }
1602
1603 static int len_ext_prop(struct usb_configuration *c, int interface)
1604 {
1605         struct usb_function *f;
1606         struct usb_os_desc *d;
1607         int j, res;
1608
1609         res = 10; /* header length */
1610         f = c->interface[interface];
1611         for (j = 0; j < f->os_desc_n; ++j) {
1612                 if (interface != f->os_desc_table[j].if_id)
1613                         continue;
1614                 d = f->os_desc_table[j].os_desc;
1615                 if (d)
1616                         return min(res + d->ext_prop_len, 4096);
1617         }
1618         return res;
1619 }
1620
1621 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1622 {
1623         struct usb_function *f;
1624         struct usb_os_desc *d;
1625         struct usb_os_desc_ext_prop *ext_prop;
1626         int j, count, n, ret;
1627
1628         f = c->interface[interface];
1629         count = 10; /* header length */
1630         buf += 10;
1631         for (j = 0; j < f->os_desc_n; ++j) {
1632                 if (interface != f->os_desc_table[j].if_id)
1633                         continue;
1634                 d = f->os_desc_table[j].os_desc;
1635                 if (d)
1636                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1637                                 n = ext_prop->data_len +
1638                                         ext_prop->name_len + 14;
1639                                 if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1640                                         return count;
1641                                 usb_ext_prop_put_size(buf, n);
1642                                 usb_ext_prop_put_type(buf, ext_prop->type);
1643                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1644                                                             ext_prop->name_len);
1645                                 if (ret < 0)
1646                                         return ret;
1647                                 switch (ext_prop->type) {
1648                                 case USB_EXT_PROP_UNICODE:
1649                                 case USB_EXT_PROP_UNICODE_ENV:
1650                                 case USB_EXT_PROP_UNICODE_LINK:
1651                                         usb_ext_prop_put_unicode(buf, ret,
1652                                                          ext_prop->data,
1653                                                          ext_prop->data_len);
1654                                         break;
1655                                 case USB_EXT_PROP_BINARY:
1656                                         usb_ext_prop_put_binary(buf, ret,
1657                                                         ext_prop->data,
1658                                                         ext_prop->data_len);
1659                                         break;
1660                                 case USB_EXT_PROP_LE32:
1661                                         /* not implemented */
1662                                 case USB_EXT_PROP_BE32:
1663                                         /* not implemented */
1664                                 default:
1665                                         return -EINVAL;
1666                                 }
1667                                 buf += n;
1668                                 count += n;
1669                         }
1670         }
1671
1672         return count;
1673 }
1674
1675 /*
1676  * The setup() callback implements all the ep0 functionality that's
1677  * not handled lower down, in hardware or the hardware driver(like
1678  * device and endpoint feature flags, and their status).  It's all
1679  * housekeeping for the gadget function we're implementing.  Most of
1680  * the work is in config and function specific setup.
1681  */
1682 int
1683 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1684 {
1685         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1686         struct usb_request              *req = cdev->req;
1687         int                             value = -EOPNOTSUPP;
1688         int                             status = 0;
1689         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1690         u8                              intf = w_index & 0xFF;
1691         u16                             w_value = le16_to_cpu(ctrl->wValue);
1692         u16                             w_length = le16_to_cpu(ctrl->wLength);
1693         struct usb_function             *f = NULL;
1694         struct usb_function             *iter;
1695         u8                              endp;
1696
1697         if (w_length > USB_COMP_EP0_BUFSIZ) {
1698                 if (ctrl->bRequestType & USB_DIR_IN) {
1699                         /* Cast away the const, we are going to overwrite on purpose. */
1700                         __le16 *temp = (__le16 *)&ctrl->wLength;
1701
1702                         *temp = cpu_to_le16(USB_COMP_EP0_BUFSIZ);
1703                         w_length = USB_COMP_EP0_BUFSIZ;
1704                 } else {
1705                         goto done;
1706                 }
1707         }
1708
1709         /* partial re-init of the response message; the function or the
1710          * gadget might need to intercept e.g. a control-OUT completion
1711          * when we delegate to it.
1712          */
1713         req->zero = 0;
1714         req->context = cdev;
1715         req->complete = composite_setup_complete;
1716         req->length = 0;
1717         gadget->ep0->driver_data = cdev;
1718
1719         /*
1720          * Don't let non-standard requests match any of the cases below
1721          * by accident.
1722          */
1723         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1724                 goto unknown;
1725
1726         switch (ctrl->bRequest) {
1727
1728         /* we handle all standard USB descriptors */
1729         case USB_REQ_GET_DESCRIPTOR:
1730                 if (ctrl->bRequestType != USB_DIR_IN)
1731                         goto unknown;
1732                 switch (w_value >> 8) {
1733
1734                 case USB_DT_DEVICE:
1735                         cdev->desc.bNumConfigurations =
1736                                 count_configs(cdev, USB_DT_DEVICE);
1737                         cdev->desc.bMaxPacketSize0 =
1738                                 cdev->gadget->ep0->maxpacket;
1739                         if (gadget_is_superspeed(gadget)) {
1740                                 if (gadget->speed >= USB_SPEED_SUPER) {
1741                                         cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1742                                         cdev->desc.bMaxPacketSize0 = 9;
1743                                 } else {
1744                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1745                                 }
1746                         } else {
1747                                 if (gadget->lpm_capable)
1748                                         cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1749                                 else
1750                                         cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1751                         }
1752
1753                         value = min(w_length, (u16) sizeof cdev->desc);
1754                         memcpy(req->buf, &cdev->desc, value);
1755                         break;
1756                 case USB_DT_DEVICE_QUALIFIER:
1757                         if (!gadget_is_dualspeed(gadget) ||
1758                             gadget->speed >= USB_SPEED_SUPER)
1759                                 break;
1760                         device_qual(cdev);
1761                         value = min_t(int, w_length,
1762                                 sizeof(struct usb_qualifier_descriptor));
1763                         break;
1764                 case USB_DT_OTHER_SPEED_CONFIG:
1765                         if (!gadget_is_dualspeed(gadget) ||
1766                             gadget->speed >= USB_SPEED_SUPER)
1767                                 break;
1768                         fallthrough;
1769                 case USB_DT_CONFIG:
1770                         value = config_desc(cdev, w_value);
1771                         if (value >= 0)
1772                                 value = min(w_length, (u16) value);
1773                         break;
1774                 case USB_DT_STRING:
1775                         value = get_string(cdev, req->buf,
1776                                         w_index, w_value & 0xff);
1777                         if (value >= 0)
1778                                 value = min(w_length, (u16) value);
1779                         break;
1780                 case USB_DT_BOS:
1781                         if (gadget_is_superspeed(gadget) ||
1782                             gadget->lpm_capable) {
1783                                 value = bos_desc(cdev);
1784                                 value = min(w_length, (u16) value);
1785                         }
1786                         break;
1787                 case USB_DT_OTG:
1788                         if (gadget_is_otg(gadget)) {
1789                                 struct usb_configuration *config;
1790                                 int otg_desc_len = 0;
1791
1792                                 if (cdev->config)
1793                                         config = cdev->config;
1794                                 else
1795                                         config = list_first_entry(
1796                                                         &cdev->configs,
1797                                                 struct usb_configuration, list);
1798                                 if (!config)
1799                                         goto done;
1800
1801                                 if (gadget->otg_caps &&
1802                                         (gadget->otg_caps->otg_rev >= 0x0200))
1803                                         otg_desc_len += sizeof(
1804                                                 struct usb_otg20_descriptor);
1805                                 else
1806                                         otg_desc_len += sizeof(
1807                                                 struct usb_otg_descriptor);
1808
1809                                 value = min_t(int, w_length, otg_desc_len);
1810                                 memcpy(req->buf, config->descriptors[0], value);
1811                         }
1812                         break;
1813                 }
1814                 break;
1815
1816         /* any number of configs can work */
1817         case USB_REQ_SET_CONFIGURATION:
1818                 if (ctrl->bRequestType != 0)
1819                         goto unknown;
1820                 if (gadget_is_otg(gadget)) {
1821                         if (gadget->a_hnp_support)
1822                                 DBG(cdev, "HNP available\n");
1823                         else if (gadget->a_alt_hnp_support)
1824                                 DBG(cdev, "HNP on another port\n");
1825                         else
1826                                 VDBG(cdev, "HNP inactive\n");
1827                 }
1828                 spin_lock(&cdev->lock);
1829                 value = set_config(cdev, ctrl, w_value);
1830                 spin_unlock(&cdev->lock);
1831                 break;
1832         case USB_REQ_GET_CONFIGURATION:
1833                 if (ctrl->bRequestType != USB_DIR_IN)
1834                         goto unknown;
1835                 if (cdev->config)
1836                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1837                 else
1838                         *(u8 *)req->buf = 0;
1839                 value = min(w_length, (u16) 1);
1840                 break;
1841
1842         /* function drivers must handle get/set altsetting */
1843         case USB_REQ_SET_INTERFACE:
1844                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1845                         goto unknown;
1846                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1847                         break;
1848                 f = cdev->config->interface[intf];
1849                 if (!f)
1850                         break;
1851
1852                 /*
1853                  * If there's no get_alt() method, we know only altsetting zero
1854                  * works. There is no need to check if set_alt() is not NULL
1855                  * as we check this in usb_add_function().
1856                  */
1857                 if (w_value && !f->get_alt)
1858                         break;
1859
1860                 spin_lock(&cdev->lock);
1861                 value = f->set_alt(f, w_index, w_value);
1862                 if (value == USB_GADGET_DELAYED_STATUS) {
1863                         DBG(cdev,
1864                          "%s: interface %d (%s) requested delayed status\n",
1865                                         __func__, intf, f->name);
1866                         cdev->delayed_status++;
1867                         DBG(cdev, "delayed_status count %d\n",
1868                                         cdev->delayed_status);
1869                 }
1870                 spin_unlock(&cdev->lock);
1871                 break;
1872         case USB_REQ_GET_INTERFACE:
1873                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1874                         goto unknown;
1875                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1876                         break;
1877                 f = cdev->config->interface[intf];
1878                 if (!f)
1879                         break;
1880                 /* lots of interfaces only need altsetting zero... */
1881                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1882                 if (value < 0)
1883                         break;
1884                 *((u8 *)req->buf) = value;
1885                 value = min(w_length, (u16) 1);
1886                 break;
1887         case USB_REQ_GET_STATUS:
1888                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1889                                                 (w_index == OTG_STS_SELECTOR)) {
1890                         if (ctrl->bRequestType != (USB_DIR_IN |
1891                                                         USB_RECIP_DEVICE))
1892                                 goto unknown;
1893                         *((u8 *)req->buf) = gadget->host_request_flag;
1894                         value = 1;
1895                         break;
1896                 }
1897
1898                 /*
1899                  * USB 3.0 additions:
1900                  * Function driver should handle get_status request. If such cb
1901                  * wasn't supplied we respond with default value = 0
1902                  * Note: function driver should supply such cb only for the
1903                  * first interface of the function
1904                  */
1905                 if (!gadget_is_superspeed(gadget))
1906                         goto unknown;
1907                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1908                         goto unknown;
1909                 value = 2;      /* This is the length of the get_status reply */
1910                 put_unaligned_le16(0, req->buf);
1911                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1912                         break;
1913                 f = cdev->config->interface[intf];
1914                 if (!f)
1915                         break;
1916                 status = f->get_status ? f->get_status(f) : 0;
1917                 if (status < 0)
1918                         break;
1919                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1920                 break;
1921         /*
1922          * Function drivers should handle SetFeature/ClearFeature
1923          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1924          * only for the first interface of the function
1925          */
1926         case USB_REQ_CLEAR_FEATURE:
1927         case USB_REQ_SET_FEATURE:
1928                 if (!gadget_is_superspeed(gadget))
1929                         goto unknown;
1930                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1931                         goto unknown;
1932                 switch (w_value) {
1933                 case USB_INTRF_FUNC_SUSPEND:
1934                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1935                                 break;
1936                         f = cdev->config->interface[intf];
1937                         if (!f)
1938                                 break;
1939                         value = 0;
1940                         if (f->func_suspend)
1941                                 value = f->func_suspend(f, w_index >> 8);
1942                         if (value < 0) {
1943                                 ERROR(cdev,
1944                                       "func_suspend() returned error %d\n",
1945                                       value);
1946                                 value = 0;
1947                         }
1948                         break;
1949                 }
1950                 break;
1951         default:
1952 unknown:
1953                 /*
1954                  * OS descriptors handling
1955                  */
1956                 if (cdev->use_os_string && cdev->os_desc_config &&
1957                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1958                     ctrl->bRequest == cdev->b_vendor_code) {
1959                         struct usb_configuration        *os_desc_cfg;
1960                         u8                              *buf;
1961                         int                             interface;
1962                         int                             count = 0;
1963
1964                         req = cdev->os_desc_req;
1965                         req->context = cdev;
1966                         req->complete = composite_setup_complete;
1967                         buf = req->buf;
1968                         os_desc_cfg = cdev->os_desc_config;
1969                         w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1970                         memset(buf, 0, w_length);
1971                         buf[5] = 0x01;
1972                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1973                         case USB_RECIP_DEVICE:
1974                                 if (w_index != 0x4 || (w_value >> 8))
1975                                         break;
1976                                 buf[6] = w_index;
1977                                 /* Number of ext compat interfaces */
1978                                 count = count_ext_compat(os_desc_cfg);
1979                                 buf[8] = count;
1980                                 count *= 24; /* 24 B/ext compat desc */
1981                                 count += 16; /* header */
1982                                 put_unaligned_le32(count, buf);
1983                                 value = w_length;
1984                                 if (w_length > 0x10) {
1985                                         value = fill_ext_compat(os_desc_cfg, buf);
1986                                         value = min_t(u16, w_length, value);
1987                                 }
1988                                 break;
1989                         case USB_RECIP_INTERFACE:
1990                                 if (w_index != 0x5 || (w_value >> 8))
1991                                         break;
1992                                 interface = w_value & 0xFF;
1993                                 if (interface >= MAX_CONFIG_INTERFACES ||
1994                                     !os_desc_cfg->interface[interface])
1995                                         break;
1996                                 buf[6] = w_index;
1997                                 count = count_ext_prop(os_desc_cfg,
1998                                         interface);
1999                                 put_unaligned_le16(count, buf + 8);
2000                                 count = len_ext_prop(os_desc_cfg,
2001                                         interface);
2002                                 put_unaligned_le32(count, buf);
2003                                 value = w_length;
2004                                 if (w_length > 0x0A) {
2005                                         value = fill_ext_prop(os_desc_cfg,
2006                                                               interface, buf);
2007                                         if (value >= 0)
2008                                                 value = min_t(u16, w_length, value);
2009                                 }
2010                                 break;
2011                         }
2012
2013                         goto check_value;
2014                 }
2015
2016                 VDBG(cdev,
2017                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
2018                         ctrl->bRequestType, ctrl->bRequest,
2019                         w_value, w_index, w_length);
2020
2021                 /* functions always handle their interfaces and endpoints...
2022                  * punt other recipients (other, WUSB, ...) to the current
2023                  * configuration code.
2024                  */
2025                 if (cdev->config) {
2026                         list_for_each_entry(f, &cdev->config->functions, list)
2027                                 if (f->req_match &&
2028                                     f->req_match(f, ctrl, false))
2029                                         goto try_fun_setup;
2030                 } else {
2031                         struct usb_configuration *c;
2032                         list_for_each_entry(c, &cdev->configs, list)
2033                                 list_for_each_entry(f, &c->functions, list)
2034                                         if (f->req_match &&
2035                                             f->req_match(f, ctrl, true))
2036                                                 goto try_fun_setup;
2037                 }
2038                 f = NULL;
2039
2040                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
2041                 case USB_RECIP_INTERFACE:
2042                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2043                                 break;
2044                         f = cdev->config->interface[intf];
2045                         break;
2046
2047                 case USB_RECIP_ENDPOINT:
2048                         if (!cdev->config)
2049                                 break;
2050                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2051                         list_for_each_entry(iter, &cdev->config->functions, list) {
2052                                 if (test_bit(endp, iter->endpoints)) {
2053                                         f = iter;
2054                                         break;
2055                                 }
2056                         }
2057                         break;
2058                 }
2059 try_fun_setup:
2060                 if (f && f->setup)
2061                         value = f->setup(f, ctrl);
2062                 else {
2063                         struct usb_configuration        *c;
2064
2065                         c = cdev->config;
2066                         if (!c)
2067                                 goto done;
2068
2069                         /* try current config's setup */
2070                         if (c->setup) {
2071                                 value = c->setup(c, ctrl);
2072                                 goto done;
2073                         }
2074
2075                         /* try the only function in the current config */
2076                         if (!list_is_singular(&c->functions))
2077                                 goto done;
2078                         f = list_first_entry(&c->functions, struct usb_function,
2079                                              list);
2080                         if (f->setup)
2081                                 value = f->setup(f, ctrl);
2082                 }
2083
2084                 goto done;
2085         }
2086
2087 check_value:
2088         /* respond with data transfer before status phase? */
2089         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2090                 req->length = value;
2091                 req->context = cdev;
2092                 req->zero = value < w_length;
2093                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2094                 if (value < 0) {
2095                         DBG(cdev, "ep_queue --> %d\n", value);
2096                         req->status = 0;
2097                         composite_setup_complete(gadget->ep0, req);
2098                 }
2099         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2100                 WARN(cdev,
2101                         "%s: Delayed status not supported for w_length != 0",
2102                         __func__);
2103         }
2104
2105 done:
2106         /* device either stalls (value < 0) or reports success */
2107         return value;
2108 }
2109
2110 static void __composite_disconnect(struct usb_gadget *gadget)
2111 {
2112         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2113         unsigned long                   flags;
2114
2115         /* REVISIT:  should we have config and device level
2116          * disconnect callbacks?
2117          */
2118         spin_lock_irqsave(&cdev->lock, flags);
2119         cdev->suspended = 0;
2120         if (cdev->config)
2121                 reset_config(cdev);
2122         if (cdev->driver->disconnect)
2123                 cdev->driver->disconnect(cdev);
2124         spin_unlock_irqrestore(&cdev->lock, flags);
2125 }
2126
2127 void composite_disconnect(struct usb_gadget *gadget)
2128 {
2129         usb_gadget_vbus_draw(gadget, 0);
2130         __composite_disconnect(gadget);
2131 }
2132
2133 void composite_reset(struct usb_gadget *gadget)
2134 {
2135         /*
2136          * Section 1.4.13 Standard Downstream Port of the USB battery charging
2137          * specification v1.2 states that a device connected on a SDP shall only
2138          * draw at max 100mA while in a connected, but unconfigured state.
2139          */
2140         usb_gadget_vbus_draw(gadget, 100);
2141         __composite_disconnect(gadget);
2142 }
2143
2144 /*-------------------------------------------------------------------------*/
2145
2146 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2147                               char *buf)
2148 {
2149         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2150         struct usb_composite_dev *cdev = get_gadget_data(gadget);
2151
2152         return sprintf(buf, "%d\n", cdev->suspended);
2153 }
2154 static DEVICE_ATTR_RO(suspended);
2155
2156 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2157 {
2158         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2159         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2160         struct usb_string               *dev_str = gstr->strings;
2161
2162         /* composite_disconnect() must already have been called
2163          * by the underlying peripheral controller driver!
2164          * so there's no i/o concurrency that could affect the
2165          * state protected by cdev->lock.
2166          */
2167         WARN_ON(cdev->config);
2168
2169         while (!list_empty(&cdev->configs)) {
2170                 struct usb_configuration        *c;
2171                 c = list_first_entry(&cdev->configs,
2172                                 struct usb_configuration, list);
2173                 remove_config(cdev, c);
2174         }
2175         if (cdev->driver->unbind && unbind_driver)
2176                 cdev->driver->unbind(cdev);
2177
2178         composite_dev_cleanup(cdev);
2179
2180         if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2181                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2182
2183         kfree(cdev->def_manufacturer);
2184         kfree(cdev);
2185         set_gadget_data(gadget, NULL);
2186 }
2187
2188 static void composite_unbind(struct usb_gadget *gadget)
2189 {
2190         __composite_unbind(gadget, true);
2191 }
2192
2193 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2194                 const struct usb_device_descriptor *old)
2195 {
2196         __le16 idVendor;
2197         __le16 idProduct;
2198         __le16 bcdDevice;
2199         u8 iSerialNumber;
2200         u8 iManufacturer;
2201         u8 iProduct;
2202
2203         /*
2204          * these variables may have been set in
2205          * usb_composite_overwrite_options()
2206          */
2207         idVendor = new->idVendor;
2208         idProduct = new->idProduct;
2209         bcdDevice = new->bcdDevice;
2210         iSerialNumber = new->iSerialNumber;
2211         iManufacturer = new->iManufacturer;
2212         iProduct = new->iProduct;
2213
2214         *new = *old;
2215         if (idVendor)
2216                 new->idVendor = idVendor;
2217         if (idProduct)
2218                 new->idProduct = idProduct;
2219         if (bcdDevice)
2220                 new->bcdDevice = bcdDevice;
2221         else
2222                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2223         if (iSerialNumber)
2224                 new->iSerialNumber = iSerialNumber;
2225         if (iManufacturer)
2226                 new->iManufacturer = iManufacturer;
2227         if (iProduct)
2228                 new->iProduct = iProduct;
2229 }
2230
2231 int composite_dev_prepare(struct usb_composite_driver *composite,
2232                 struct usb_composite_dev *cdev)
2233 {
2234         struct usb_gadget *gadget = cdev->gadget;
2235         int ret = -ENOMEM;
2236
2237         /* preallocate control response and buffer */
2238         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2239         if (!cdev->req)
2240                 return -ENOMEM;
2241
2242         cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2243         if (!cdev->req->buf)
2244                 goto fail;
2245
2246         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2247         if (ret)
2248                 goto fail_dev;
2249
2250         cdev->req->complete = composite_setup_complete;
2251         cdev->req->context = cdev;
2252         gadget->ep0->driver_data = cdev;
2253
2254         cdev->driver = composite;
2255
2256         /*
2257          * As per USB compliance update, a device that is actively drawing
2258          * more than 100mA from USB must report itself as bus-powered in
2259          * the GetStatus(DEVICE) call.
2260          */
2261         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2262                 usb_gadget_set_selfpowered(gadget);
2263
2264         /* interface and string IDs start at zero via kzalloc.
2265          * we force endpoints to start unassigned; few controller
2266          * drivers will zero ep->driver_data.
2267          */
2268         usb_ep_autoconfig_reset(gadget);
2269         return 0;
2270 fail_dev:
2271         kfree(cdev->req->buf);
2272 fail:
2273         usb_ep_free_request(gadget->ep0, cdev->req);
2274         cdev->req = NULL;
2275         return ret;
2276 }
2277
2278 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2279                                   struct usb_ep *ep0)
2280 {
2281         int ret = 0;
2282
2283         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2284         if (!cdev->os_desc_req) {
2285                 ret = -ENOMEM;
2286                 goto end;
2287         }
2288
2289         cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2290                                          GFP_KERNEL);
2291         if (!cdev->os_desc_req->buf) {
2292                 ret = -ENOMEM;
2293                 usb_ep_free_request(ep0, cdev->os_desc_req);
2294                 goto end;
2295         }
2296         cdev->os_desc_req->context = cdev;
2297         cdev->os_desc_req->complete = composite_setup_complete;
2298 end:
2299         return ret;
2300 }
2301
2302 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2303 {
2304         struct usb_gadget_string_container *uc, *tmp;
2305         struct usb_ep                      *ep, *tmp_ep;
2306
2307         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2308                 list_del(&uc->list);
2309                 kfree(uc);
2310         }
2311         if (cdev->os_desc_req) {
2312                 if (cdev->os_desc_pending)
2313                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2314
2315                 kfree(cdev->os_desc_req->buf);
2316                 cdev->os_desc_req->buf = NULL;
2317                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2318                 cdev->os_desc_req = NULL;
2319         }
2320         if (cdev->req) {
2321                 if (cdev->setup_pending)
2322                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2323
2324                 kfree(cdev->req->buf);
2325                 cdev->req->buf = NULL;
2326                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2327                 cdev->req = NULL;
2328         }
2329         cdev->next_string_id = 0;
2330         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2331
2332         /*
2333          * Some UDC backends have a dynamic EP allocation scheme.
2334          *
2335          * In that case, the dispose() callback is used to notify the
2336          * backend that the EPs are no longer in use.
2337          *
2338          * Note: The UDC backend can remove the EP from the ep_list as
2339          *       a result, so we need to use the _safe list iterator.
2340          */
2341         list_for_each_entry_safe(ep, tmp_ep,
2342                                  &cdev->gadget->ep_list, ep_list) {
2343                 if (ep->ops->dispose)
2344                         ep->ops->dispose(ep);
2345         }
2346 }
2347
2348 static int composite_bind(struct usb_gadget *gadget,
2349                 struct usb_gadget_driver *gdriver)
2350 {
2351         struct usb_composite_dev        *cdev;
2352         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2353         int                             status = -ENOMEM;
2354
2355         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2356         if (!cdev)
2357                 return status;
2358
2359         spin_lock_init(&cdev->lock);
2360         cdev->gadget = gadget;
2361         set_gadget_data(gadget, cdev);
2362         INIT_LIST_HEAD(&cdev->configs);
2363         INIT_LIST_HEAD(&cdev->gstrings);
2364
2365         status = composite_dev_prepare(composite, cdev);
2366         if (status)
2367                 goto fail;
2368
2369         /* composite gadget needs to assign strings for whole device (like
2370          * serial number), register function drivers, potentially update
2371          * power state and consumption, etc
2372          */
2373         status = composite->bind(cdev);
2374         if (status < 0)
2375                 goto fail;
2376
2377         if (cdev->use_os_string) {
2378                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2379                 if (status)
2380                         goto fail;
2381         }
2382
2383         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2384
2385         /* has userspace failed to provide a serial number? */
2386         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2387                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2388
2389         INFO(cdev, "%s ready\n", composite->name);
2390         return 0;
2391
2392 fail:
2393         __composite_unbind(gadget, false);
2394         return status;
2395 }
2396
2397 /*-------------------------------------------------------------------------*/
2398
2399 void composite_suspend(struct usb_gadget *gadget)
2400 {
2401         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2402         struct usb_function             *f;
2403
2404         /* REVISIT:  should we have config level
2405          * suspend/resume callbacks?
2406          */
2407         DBG(cdev, "suspend\n");
2408         if (cdev->config) {
2409                 list_for_each_entry(f, &cdev->config->functions, list) {
2410                         if (f->suspend)
2411                                 f->suspend(f);
2412                 }
2413         }
2414         if (cdev->driver->suspend)
2415                 cdev->driver->suspend(cdev);
2416
2417         cdev->suspended = 1;
2418
2419         usb_gadget_set_selfpowered(gadget);
2420         usb_gadget_vbus_draw(gadget, 2);
2421 }
2422
2423 void composite_resume(struct usb_gadget *gadget)
2424 {
2425         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2426         struct usb_function             *f;
2427         unsigned                        maxpower;
2428
2429         /* REVISIT:  should we have config level
2430          * suspend/resume callbacks?
2431          */
2432         DBG(cdev, "resume\n");
2433         if (cdev->driver->resume)
2434                 cdev->driver->resume(cdev);
2435         if (cdev->config) {
2436                 list_for_each_entry(f, &cdev->config->functions, list) {
2437                         if (f->resume)
2438                                 f->resume(f);
2439                 }
2440
2441                 maxpower = cdev->config->MaxPower ?
2442                         cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2443                 if (gadget->speed < USB_SPEED_SUPER)
2444                         maxpower = min(maxpower, 500U);
2445                 else
2446                         maxpower = min(maxpower, 900U);
2447
2448                 if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2449                         usb_gadget_clear_selfpowered(gadget);
2450
2451                 usb_gadget_vbus_draw(gadget, maxpower);
2452         }
2453
2454         cdev->suspended = 0;
2455 }
2456
2457 /*-------------------------------------------------------------------------*/
2458
2459 static const struct usb_gadget_driver composite_driver_template = {
2460         .bind           = composite_bind,
2461         .unbind         = composite_unbind,
2462
2463         .setup          = composite_setup,
2464         .reset          = composite_reset,
2465         .disconnect     = composite_disconnect,
2466
2467         .suspend        = composite_suspend,
2468         .resume         = composite_resume,
2469
2470         .driver = {
2471                 .owner          = THIS_MODULE,
2472         },
2473 };
2474
2475 /**
2476  * usb_composite_probe() - register a composite driver
2477  * @driver: the driver to register
2478  *
2479  * Context: single threaded during gadget setup
2480  *
2481  * This function is used to register drivers using the composite driver
2482  * framework.  The return value is zero, or a negative errno value.
2483  * Those values normally come from the driver's @bind method, which does
2484  * all the work of setting up the driver to match the hardware.
2485  *
2486  * On successful return, the gadget is ready to respond to requests from
2487  * the host, unless one of its components invokes usb_gadget_disconnect()
2488  * while it was binding.  That would usually be done in order to wait for
2489  * some userspace participation.
2490  */
2491 int usb_composite_probe(struct usb_composite_driver *driver)
2492 {
2493         struct usb_gadget_driver *gadget_driver;
2494
2495         if (!driver || !driver->dev || !driver->bind)
2496                 return -EINVAL;
2497
2498         if (!driver->name)
2499                 driver->name = "composite";
2500
2501         driver->gadget_driver = composite_driver_template;
2502         gadget_driver = &driver->gadget_driver;
2503
2504         gadget_driver->function =  (char *) driver->name;
2505         gadget_driver->driver.name = driver->name;
2506         gadget_driver->max_speed = driver->max_speed;
2507
2508         return usb_gadget_register_driver(gadget_driver);
2509 }
2510 EXPORT_SYMBOL_GPL(usb_composite_probe);
2511
2512 /**
2513  * usb_composite_unregister() - unregister a composite driver
2514  * @driver: the driver to unregister
2515  *
2516  * This function is used to unregister drivers using the composite
2517  * driver framework.
2518  */
2519 void usb_composite_unregister(struct usb_composite_driver *driver)
2520 {
2521         usb_gadget_unregister_driver(&driver->gadget_driver);
2522 }
2523 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2524
2525 /**
2526  * usb_composite_setup_continue() - Continue with the control transfer
2527  * @cdev: the composite device who's control transfer was kept waiting
2528  *
2529  * This function must be called by the USB function driver to continue
2530  * with the control transfer's data/status stage in case it had requested to
2531  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2532  * can request the composite framework to delay the setup request's data/status
2533  * stages by returning USB_GADGET_DELAYED_STATUS.
2534  */
2535 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2536 {
2537         int                     value;
2538         struct usb_request      *req = cdev->req;
2539         unsigned long           flags;
2540
2541         DBG(cdev, "%s\n", __func__);
2542         spin_lock_irqsave(&cdev->lock, flags);
2543
2544         if (cdev->delayed_status == 0) {
2545                 WARN(cdev, "%s: Unexpected call\n", __func__);
2546
2547         } else if (--cdev->delayed_status == 0) {
2548                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2549                 req->length = 0;
2550                 req->context = cdev;
2551                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2552                 if (value < 0) {
2553                         DBG(cdev, "ep_queue --> %d\n", value);
2554                         req->status = 0;
2555                         composite_setup_complete(cdev->gadget->ep0, req);
2556                 }
2557         }
2558
2559         spin_unlock_irqrestore(&cdev->lock, flags);
2560 }
2561 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2562
2563 static char *composite_default_mfr(struct usb_gadget *gadget)
2564 {
2565         return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2566                          init_utsname()->release, gadget->name);
2567 }
2568
2569 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2570                 struct usb_composite_overwrite *covr)
2571 {
2572         struct usb_device_descriptor    *desc = &cdev->desc;
2573         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2574         struct usb_string               *dev_str = gstr->strings;
2575
2576         if (covr->idVendor)
2577                 desc->idVendor = cpu_to_le16(covr->idVendor);
2578
2579         if (covr->idProduct)
2580                 desc->idProduct = cpu_to_le16(covr->idProduct);
2581
2582         if (covr->bcdDevice)
2583                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2584
2585         if (covr->serial_number) {
2586                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2587                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2588         }
2589         if (covr->manufacturer) {
2590                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2591                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2592
2593         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2594                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2595                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2596                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2597         }
2598
2599         if (covr->product) {
2600                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2601                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2602         }
2603 }
2604 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2605
2606 MODULE_LICENSE("GPL");
2607 MODULE_AUTHOR("David Brownell");