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