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