drivers/usb/gadget/composite.c

   1 /*
   2  * composite.c - infrastructure for Composite USB Gadgets
   3  *
   4  * Copyright (C) 2006-2008 David Brownell
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 /* #define VERBOSE_DEBUG */
  13
  14 #include <linux/kallsyms.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/device.h>
  19 #include <linux/utsname.h>
  20
  21 #include <linux/usb/composite.h>
  22 #include <linux/usb/otg.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "u_os_desc.h"
  26
  27 /**
  28  * struct usb_os_string - represents OS String to be reported by a gadget
  29  * @bLength: total length of the entire descritor, always 0x12
  30  * @bDescriptorType: USB_DT_STRING
  31  * @qwSignature: the OS String proper
  32  * @bMS_VendorCode: code used by the host for subsequent requests
  33  * @bPad: not used, must be zero
  34  */
  35 struct usb_os_string {
  36         __u8    bLength;
  37         __u8    bDescriptorType;
  38         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  39         __u8    bMS_VendorCode;
  40         __u8    bPad;
  41 } __packed;
  42
  43 /*
  44  * The code in this file is utility code, used to build a gadget driver
  45  * from one or more "function" drivers, one or more "configuration"
  46  * objects, and a "usb_composite_driver" by gluing them together along
  47  * with the relevant device-wide data.
  48  */
  49
  50 static struct usb_gadget_strings **get_containers_gs(
  51                 struct usb_gadget_string_container *uc)
  52 {
  53         return (struct usb_gadget_strings **)uc->stash;
  54 }
  55
  56 /**
  57  * function_descriptors() - get function descriptors for speed
  58  * @f: the function
  59  * @speed: the speed
  60  *
  61  * Returns the descriptors or NULL if not set.
  62  */
  63 static struct usb_descriptor_header **
  64 function_descriptors(struct usb_function *f,
  65                      enum usb_device_speed speed)
  66 {
  67         struct usb_descriptor_header **descriptors;
  68
  69         switch (speed) {
  70         case USB_SPEED_SUPER_PLUS:
  71                 descriptors = f->ssp_descriptors;
  72                 break;
  73         case USB_SPEED_SUPER:
  74                 descriptors = f->ss_descriptors;
  75                 break;
  76         case USB_SPEED_HIGH:
  77                 descriptors = f->hs_descriptors;
  78                 break;
  79         default:
  80                 descriptors = f->fs_descriptors;
  81         }
  82
  83         return descriptors;
  84 }
  85
  86 /**
  87  * next_ep_desc() - advance to the next EP descriptor
  88  * @t: currect pointer within descriptor array
  89  *
  90  * Return: next EP descriptor or NULL
  91  *
  92  * Iterate over @t until either EP descriptor found or
  93  * NULL (that indicates end of list) encountered
  94  */
  95 static struct usb_descriptor_header**
  96 next_ep_desc(struct usb_descriptor_header **t)
  97 {
  98         for (; *t; t++) {
  99                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
 100                         return t;
 101         }
 102         return NULL;
 103 }
 104
 105 /*
 106  * for_each_ep_desc()- iterate over endpoint descriptors in the
 107  *              descriptors list
 108  * @start:      pointer within descriptor array.
 109  * @ep_desc:    endpoint descriptor to use as the loop cursor
 110  */
 111 #define for_each_ep_desc(start, ep_desc) \
 112         for (ep_desc = next_ep_desc(start); \
 113               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
 114
 115 /**
 116  * config_ep_by_speed() - configures the given endpoint
 117  * according to gadget speed.
 118  * @g: pointer to the gadget
 119  * @f: usb function
 120  * @_ep: the endpoint to configure
 121  *
 122  * Return: error code, 0 on success
 123  *
 124  * This function chooses the right descriptors for a given
 125  * endpoint according to gadget speed and saves it in the
 126  * endpoint desc field. If the endpoint already has a descriptor
 127  * assigned to it - overwrites it with currently corresponding
 128  * descriptor. The endpoint maxpacket field is updated according
 129  * to the chosen descriptor.
 130  * Note: the supplied function should hold all the descriptors
 131  * for supported speeds
 132  */
 133 int config_ep_by_speed(struct usb_gadget *g,
 134                         struct usb_function *f,
 135                         struct usb_ep *_ep)
 136 {
 137         struct usb_composite_dev        *cdev = get_gadget_data(g);
 138         struct usb_endpoint_descriptor *chosen_desc = NULL;
 139         struct usb_descriptor_header **speed_desc = NULL;
 140
 141         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 142         int want_comp_desc = 0;
 143
 144         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 145
 146         if (!g || !f || !_ep)
 147                 return -EIO;
 148
 149         /* select desired speed */
 150         switch (g->speed) {
 151         case USB_SPEED_SUPER_PLUS:
 152                 if (gadget_is_superspeed_plus(g)) {
 153                         speed_desc = f->ssp_descriptors;
 154                         want_comp_desc = 1;
 155                         break;
 156                 }
 157                 /* else: Fall trough */
 158         case USB_SPEED_SUPER:
 159                 if (gadget_is_superspeed(g)) {
 160                         speed_desc = f->ss_descriptors;
 161                         want_comp_desc = 1;
 162                         break;
 163                 }
 164                 /* else: Fall trough */
 165         case USB_SPEED_HIGH:
 166                 if (gadget_is_dualspeed(g)) {
 167                         speed_desc = f->hs_descriptors;
 168                         break;
 169                 }
 170                 /* else: fall through */
 171         default:
 172                 speed_desc = f->fs_descriptors;
 173         }
 174         /* find descriptors */
 175         for_each_ep_desc(speed_desc, d_spd) {
 176                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 177                 if (chosen_desc->bEndpointAddress == _ep->address)
 178                         goto ep_found;
 179         }
 180         return -EIO;
 181
 182 ep_found:
 183         /* commit results */
 184         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 185         _ep->desc = chosen_desc;
 186         _ep->comp_desc = NULL;
 187         _ep->maxburst = 0;
 188         _ep->mult = 0;
 189         if (!want_comp_desc)
 190                 return 0;
 191
 192         /*
 193          * Companion descriptor should follow EP descriptor
 194          * USB 3.0 spec, #9.6.7
 195          */
 196         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 197         if (!comp_desc ||
 198             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 199                 return -EIO;
 200         _ep->comp_desc = comp_desc;
 201         if (g->speed >= USB_SPEED_SUPER) {
 202                 switch (usb_endpoint_type(_ep->desc)) {
 203                 case USB_ENDPOINT_XFER_ISOC:
 204                         /* mult: bits 1:0 of bmAttributes */
 205                         _ep->mult = comp_desc->bmAttributes & 0x3;
 206                 case USB_ENDPOINT_XFER_BULK:
 207                 case USB_ENDPOINT_XFER_INT:
 208                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 209                         break;
 210                 default:
 211                         if (comp_desc->bMaxBurst != 0)
 212                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 213                         _ep->maxburst = 1;
 214                         break;
 215                 }
 216         }
 217         return 0;
 218 }
 219 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 220
 221 /**
 222  * usb_add_function() - add a function to a configuration
 223  * @config: the configuration
 224  * @function: the function being added
 225  * Context: single threaded during gadget setup
 226  *
 227  * After initialization, each configuration must have one or more
 228  * functions added to it.  Adding a function involves calling its @bind()
 229  * method to allocate resources such as interface and string identifiers
 230  * and endpoints.
 231  *
 232  * This function returns the value of the function's bind(), which is
 233  * zero for success else a negative errno value.
 234  */
 235 int usb_add_function(struct usb_configuration *config,
 236                 struct usb_function *function)
 237 {
 238         int     value = -EINVAL;
 239
 240         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 241                         function->name, function,
 242                         config->label, config);
 243
 244         if (!function->set_alt || !function->disable)
 245                 goto done;
 246
 247         function->config = config;
 248         list_add_tail(&function->list, &config->functions);
 249
 250         if (function->bind_deactivated) {
 251                 value = usb_function_deactivate(function);
 252                 if (value)
 253                         goto done;
 254         }
 255
 256         /* REVISIT *require* function->bind? */
 257         if (function->bind) {
 258                 value = function->bind(config, function);
 259                 if (value < 0) {
 260                         list_del(&function->list);
 261                         function->config = NULL;
 262                 }
 263         } else
 264                 value = 0;
 265
 266         /* We allow configurations that don't work at both speeds.
 267          * If we run into a lowspeed Linux system, treat it the same
 268          * as full speed ... it's the function drivers that will need
 269          * to avoid bulk and ISO transfers.
 270          */
 271         if (!config->fullspeed && function->fs_descriptors)
 272                 config->fullspeed = true;
 273         if (!config->highspeed && function->hs_descriptors)
 274                 config->highspeed = true;
 275         if (!config->superspeed && function->ss_descriptors)
 276                 config->superspeed = true;
 277         if (!config->superspeed_plus && function->ssp_descriptors)
 278                 config->superspeed_plus = true;
 279
 280 done:
 281         if (value)
 282                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 283                                 function->name, function, value);
 284         return value;
 285 }
 286 EXPORT_SYMBOL_GPL(usb_add_function);
 287
 288 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 289 {
 290         if (f->disable)
 291                 f->disable(f);
 292
 293         bitmap_zero(f->endpoints, 32);
 294         list_del(&f->list);
 295         if (f->unbind)
 296                 f->unbind(c, f);
 297 }
 298 EXPORT_SYMBOL_GPL(usb_remove_function);
 299
 300 /**
 301  * usb_function_deactivate - prevent function and gadget enumeration
 302  * @function: the function that isn't yet ready to respond
 303  *
 304  * Blocks response of the gadget driver to host enumeration by
 305  * preventing the data line pullup from being activated.  This is
 306  * normally called during @bind() processing to change from the
 307  * initial "ready to respond" state, or when a required resource
 308  * becomes available.
 309  *
 310  * For example, drivers that serve as a passthrough to a userspace
 311  * daemon can block enumeration unless that daemon (such as an OBEX,
 312  * MTP, or print server) is ready to handle host requests.
 313  *
 314  * Not all systems support software control of their USB peripheral
 315  * data pullups.
 316  *
 317  * Returns zero on success, else negative errno.
 318  */
 319 int usb_function_deactivate(struct usb_function *function)
 320 {
 321         struct usb_composite_dev        *cdev = function->config->cdev;
 322         unsigned long                   flags;
 323         int                             status = 0;
 324
 325         spin_lock_irqsave(&cdev->lock, flags);
 326
 327         if (cdev->deactivations == 0)
 328                 status = usb_gadget_deactivate(cdev->gadget);
 329         if (status == 0)
 330                 cdev->deactivations++;
 331
 332         spin_unlock_irqrestore(&cdev->lock, flags);
 333         return status;
 334 }
 335 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 336
 337 /**
 338  * usb_function_activate - allow function and gadget enumeration
 339  * @function: function on which usb_function_activate() was called
 340  *
 341  * Reverses effect of usb_function_deactivate().  If no more functions
 342  * are delaying their activation, the gadget driver will respond to
 343  * host enumeration procedures.
 344  *
 345  * Returns zero on success, else negative errno.
 346  */
 347 int usb_function_activate(struct usb_function *function)
 348 {
 349         struct usb_composite_dev        *cdev = function->config->cdev;
 350         unsigned long                   flags;
 351         int                             status = 0;
 352
 353         spin_lock_irqsave(&cdev->lock, flags);
 354
 355         if (WARN_ON(cdev->deactivations == 0))
 356                 status = -EINVAL;
 357         else {
 358                 cdev->deactivations--;
 359                 if (cdev->deactivations == 0)
 360                         status = usb_gadget_activate(cdev->gadget);
 361         }
 362
 363         spin_unlock_irqrestore(&cdev->lock, flags);
 364         return status;
 365 }
 366 EXPORT_SYMBOL_GPL(usb_function_activate);
 367
 368 /**
 369  * usb_interface_id() - allocate an unused interface ID
 370  * @config: configuration associated with the interface
 371  * @function: function handling the interface
 372  * Context: single threaded during gadget setup
 373  *
 374  * usb_interface_id() is called from usb_function.bind() callbacks to
 375  * allocate new interface IDs.  The function driver will then store that
 376  * ID in interface, association, CDC union, and other descriptors.  It
 377  * will also handle any control requests targeted at that interface,
 378  * particularly changing its altsetting via set_alt().  There may
 379  * also be class-specific or vendor-specific requests to handle.
 380  *
 381  * All interface identifier should be allocated using this routine, to
 382  * ensure that for example different functions don't wrongly assign
 383  * different meanings to the same identifier.  Note that since interface
 384  * identifiers are configuration-specific, functions used in more than
 385  * one configuration (or more than once in a given configuration) need
 386  * multiple versions of the relevant descriptors.
 387  *
 388  * Returns the interface ID which was allocated; or -ENODEV if no
 389  * more interface IDs can be allocated.
 390  */
 391 int usb_interface_id(struct usb_configuration *config,
 392                 struct usb_function *function)
 393 {
 394         unsigned id = config->next_interface_id;
 395
 396         if (id < MAX_CONFIG_INTERFACES) {
 397                 config->interface[id] = function;
 398                 config->next_interface_id = id + 1;
 399                 return id;
 400         }
 401         return -ENODEV;
 402 }
 403 EXPORT_SYMBOL_GPL(usb_interface_id);
 404
 405 static u8 encode_bMaxPower(enum usb_device_speed speed,
 406                 struct usb_configuration *c)
 407 {
 408         unsigned val;
 409
 410         if (c->MaxPower)
 411                 val = c->MaxPower;
 412         else
 413                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 414         if (!val)
 415                 return 0;
 416         switch (speed) {
 417         case USB_SPEED_SUPER:
 418                 return DIV_ROUND_UP(val, 8);
 419         default:
 420                 return DIV_ROUND_UP(val, 2);
 421         }
 422 }
 423
 424 static int config_buf(struct usb_configuration *config,
 425                 enum usb_device_speed speed, void *buf, u8 type)
 426 {
 427         struct usb_config_descriptor    *c = buf;
 428         void                            *next = buf + USB_DT_CONFIG_SIZE;
 429         int                             len;
 430         struct usb_function             *f;
 431         int                             status;
 432
 433         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 434         /* write the config descriptor */
 435         c = buf;
 436         c->bLength = USB_DT_CONFIG_SIZE;
 437         c->bDescriptorType = type;
 438         /* wTotalLength is written later */
 439         c->bNumInterfaces = config->next_interface_id;
 440         c->bConfigurationValue = config->bConfigurationValue;
 441         c->iConfiguration = config->iConfiguration;
 442         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 443         c->bMaxPower = encode_bMaxPower(speed, config);
 444
 445         /* There may be e.g. OTG descriptors */
 446         if (config->descriptors) {
 447                 status = usb_descriptor_fillbuf(next, len,
 448                                 config->descriptors);
 449                 if (status < 0)
 450                         return status;
 451                 len -= status;
 452                 next += status;
 453         }
 454
 455         /* add each function's descriptors */
 456         list_for_each_entry(f, &config->functions, list) {
 457                 struct usb_descriptor_header **descriptors;
 458
 459                 descriptors = function_descriptors(f, speed);
 460                 if (!descriptors)
 461                         continue;
 462                 status = usb_descriptor_fillbuf(next, len,
 463                         (const struct usb_descriptor_header **) descriptors);
 464                 if (status < 0)
 465                         return status;
 466                 len -= status;
 467                 next += status;
 468         }
 469
 470         len = next - buf;
 471         c->wTotalLength = cpu_to_le16(len);
 472         return len;
 473 }
 474
 475 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 476 {
 477         struct usb_gadget               *gadget = cdev->gadget;
 478         struct usb_configuration        *c;
 479         struct list_head                *pos;
 480         u8                              type = w_value >> 8;
 481         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 482
 483         if (gadget->speed >= USB_SPEED_SUPER)
 484                 speed = gadget->speed;
 485         else if (gadget_is_dualspeed(gadget)) {
 486                 int     hs = 0;
 487                 if (gadget->speed == USB_SPEED_HIGH)
 488                         hs = 1;
 489                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 490                         hs = !hs;
 491                 if (hs)
 492                         speed = USB_SPEED_HIGH;
 493
 494         }
 495
 496         /* This is a lookup by config *INDEX* */
 497         w_value &= 0xff;
 498
 499         pos = &cdev->configs;
 500         c = cdev->os_desc_config;
 501         if (c)
 502                 goto check_config;
 503
 504         while ((pos = pos->next) !=  &cdev->configs) {
 505                 c = list_entry(pos, typeof(*c), list);
 506
 507                 /* skip OS Descriptors config which is handled separately */
 508                 if (c == cdev->os_desc_config)
 509                         continue;
 510
 511 check_config:
 512                 /* ignore configs that won't work at this speed */
 513                 switch (speed) {
 514                 case USB_SPEED_SUPER_PLUS:
 515                         if (!c->superspeed_plus)
 516                                 continue;
 517                         break;
 518                 case USB_SPEED_SUPER:
 519                         if (!c->superspeed)
 520                                 continue;
 521                         break;
 522                 case USB_SPEED_HIGH:
 523                         if (!c->highspeed)
 524                                 continue;
 525                         break;
 526                 default:
 527                         if (!c->fullspeed)
 528                                 continue;
 529                 }
 530
 531                 if (w_value == 0)
 532                         return config_buf(c, speed, cdev->req->buf, type);
 533                 w_value--;
 534         }
 535         return -EINVAL;
 536 }
 537
 538 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 539 {
 540         struct usb_gadget               *gadget = cdev->gadget;
 541         struct usb_configuration        *c;
 542         unsigned                        count = 0;
 543         int                             hs = 0;
 544         int                             ss = 0;
 545         int                             ssp = 0;
 546
 547         if (gadget_is_dualspeed(gadget)) {
 548                 if (gadget->speed == USB_SPEED_HIGH)
 549                         hs = 1;
 550                 if (gadget->speed == USB_SPEED_SUPER)
 551                         ss = 1;
 552                 if (gadget->speed == USB_SPEED_SUPER_PLUS)
 553                         ssp = 1;
 554                 if (type == USB_DT_DEVICE_QUALIFIER)
 555                         hs = !hs;
 556         }
 557         list_for_each_entry(c, &cdev->configs, list) {
 558                 /* ignore configs that won't work at this speed */
 559                 if (ssp) {
 560                         if (!c->superspeed_plus)
 561                                 continue;
 562                 } else if (ss) {
 563                         if (!c->superspeed)
 564                                 continue;
 565                 } else if (hs) {
 566                         if (!c->highspeed)
 567                                 continue;
 568                 } else {
 569                         if (!c->fullspeed)
 570                                 continue;
 571                 }
 572                 count++;
 573         }
 574         return count;
 575 }
 576
 577 /**
 578  * bos_desc() - prepares the BOS descriptor.
 579  * @cdev: pointer to usb_composite device to generate the bos
 580  *      descriptor for
 581  *
 582  * This function generates the BOS (Binary Device Object)
 583  * descriptor and its device capabilities descriptors. The BOS
 584  * descriptor should be supported by a SuperSpeed device.
 585  */
 586 static int bos_desc(struct usb_composite_dev *cdev)
 587 {
 588         struct usb_ext_cap_descriptor   *usb_ext;
 589         struct usb_ss_cap_descriptor    *ss_cap;
 590         struct usb_dcd_config_params    dcd_config_params;
 591         struct usb_bos_descriptor       *bos = cdev->req->buf;
 592
 593         bos->bLength = USB_DT_BOS_SIZE;
 594         bos->bDescriptorType = USB_DT_BOS;
 595
 596         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 597         bos->bNumDeviceCaps = 0;
 598
 599         /*
 600          * A SuperSpeed device shall include the USB2.0 extension descriptor
 601          * and shall support LPM when operating in USB2.0 HS mode.
 602          */
 603         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 604         bos->bNumDeviceCaps++;
 605         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 606         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 607         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 608         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 609         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | USB_BESL_SUPPORT);
 610
 611         /*
 612          * The Superspeed USB Capability descriptor shall be implemented by all
 613          * SuperSpeed devices.
 614          */
 615         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 616         bos->bNumDeviceCaps++;
 617         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 618         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 619         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 620         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 621         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 622         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 623                                 USB_FULL_SPEED_OPERATION |
 624                                 USB_HIGH_SPEED_OPERATION |
 625                                 USB_5GBPS_OPERATION);
 626         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 627
 628         /* Get Controller configuration */
 629         if (cdev->gadget->ops->get_config_params)
 630                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 631         else {
 632                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 633                 dcd_config_params.bU2DevExitLat =
 634                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 635         }
 636         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 637         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 638
 639         /* The SuperSpeedPlus USB Device Capability descriptor */
 640         if (gadget_is_superspeed_plus(cdev->gadget)) {
 641                 struct usb_ssp_cap_descriptor *ssp_cap;
 642
 643                 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 644                 bos->bNumDeviceCaps++;
 645
 646                 /*
 647                  * Report typical values.
 648                  */
 649
 650                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
 651                 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
 652                 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 653                 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 654                 ssp_cap->bReserved = 0;
 655                 ssp_cap->wReserved = 0;
 656
 657                 /* SSAC = 1 (2 attributes) */
 658                 ssp_cap->bmAttributes = cpu_to_le32(1);
 659
 660                 /* Min RX/TX Lane Count = 1 */
 661                 ssp_cap->wFunctionalitySupport =
 662                         cpu_to_le16((1 << 8) | (1 << 12));
 663
 664                 /*
 665                  * bmSublinkSpeedAttr[0]:
 666                  *   ST  = Symmetric, RX
 667                  *   LSE =  3 (Gbps)
 668                  *   LP  =  1 (SuperSpeedPlus)
 669                  *   LSM = 10 (10 Gbps)
 670                  */
 671                 ssp_cap->bmSublinkSpeedAttr[0] =
 672                         cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
 673                 /*
 674                  * bmSublinkSpeedAttr[1] =
 675                  *   ST  = Symmetric, TX
 676                  *   LSE =  3 (Gbps)
 677                  *   LP  =  1 (SuperSpeedPlus)
 678                  *   LSM = 10 (10 Gbps)
 679                  */
 680                 ssp_cap->bmSublinkSpeedAttr[1] =
 681                         cpu_to_le32((3 << 4) | (1 << 14) |
 682                                     (0xa << 16) | (1 << 7));
 683         }
 684
 685         return le16_to_cpu(bos->wTotalLength);
 686 }
 687
 688 static void device_qual(struct usb_composite_dev *cdev)
 689 {
 690         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 691
 692         qual->bLength = sizeof(*qual);
 693         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 694         /* POLICY: same bcdUSB and device type info at both speeds */
 695         qual->bcdUSB = cdev->desc.bcdUSB;
 696         qual->bDeviceClass = cdev->desc.bDeviceClass;
 697         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 698         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 699         /* ASSUME same EP0 fifo size at both speeds */
 700         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 701         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 702         qual->bRESERVED = 0;
 703 }
 704
 705 /*-------------------------------------------------------------------------*/
 706
 707 static void reset_config(struct usb_composite_dev *cdev)
 708 {
 709         struct usb_function             *f;
 710
 711         DBG(cdev, "reset config\n");
 712
 713         list_for_each_entry(f, &cdev->config->functions, list) {
 714                 if (f->disable)
 715                         f->disable(f);
 716
 717                 bitmap_zero(f->endpoints, 32);
 718         }
 719         cdev->config = NULL;
 720         cdev->delayed_status = 0;
 721 }
 722
 723 static int set_config(struct usb_composite_dev *cdev,
 724                 const struct usb_ctrlrequest *ctrl, unsigned number)
 725 {
 726         struct usb_gadget       *gadget = cdev->gadget;
 727         struct usb_configuration *c = NULL;
 728         int                     result = -EINVAL;
 729         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 730         int                     tmp;
 731
 732         if (number) {
 733                 list_for_each_entry(c, &cdev->configs, list) {
 734                         if (c->bConfigurationValue == number) {
 735                                 /*
 736                                  * We disable the FDs of the previous
 737                                  * configuration only if the new configuration
 738                                  * is a valid one
 739                                  */
 740                                 if (cdev->config)
 741                                         reset_config(cdev);
 742                                 result = 0;
 743                                 break;
 744                         }
 745                 }
 746                 if (result < 0)
 747                         goto done;
 748         } else { /* Zero configuration value - need to reset the config */
 749                 if (cdev->config)
 750                         reset_config(cdev);
 751                 result = 0;
 752         }
 753
 754         INFO(cdev, "%s config #%d: %s\n",
 755              usb_speed_string(gadget->speed),
 756              number, c ? c->label : "unconfigured");
 757
 758         if (!c)
 759                 goto done;
 760
 761         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 762         cdev->config = c;
 763
 764         /* Initialize all interfaces by setting them to altsetting zero. */
 765         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 766                 struct usb_function     *f = c->interface[tmp];
 767                 struct usb_descriptor_header **descriptors;
 768
 769                 if (!f)
 770                         break;
 771
 772                 /*
 773                  * Record which endpoints are used by the function. This is used
 774                  * to dispatch control requests targeted at that endpoint to the
 775                  * function's setup callback instead of the current
 776                  * configuration's setup callback.
 777                  */
 778                 descriptors = function_descriptors(f, gadget->speed);
 779
 780                 for (; *descriptors; ++descriptors) {
 781                         struct usb_endpoint_descriptor *ep;
 782                         int addr;
 783
 784                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 785                                 continue;
 786
 787                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 788                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 789                              |  (ep->bEndpointAddress & 0x0f);
 790                         set_bit(addr, f->endpoints);
 791                 }
 792
 793                 result = f->set_alt(f, tmp, 0);
 794                 if (result < 0) {
 795                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 796                                         tmp, f->name, f, result);
 797
 798                         reset_config(cdev);
 799                         goto done;
 800                 }
 801
 802                 if (result == USB_GADGET_DELAYED_STATUS) {
 803                         DBG(cdev,
 804                          "%s: interface %d (%s) requested delayed status\n",
 805                                         __func__, tmp, f->name);
 806                         cdev->delayed_status++;
 807                         DBG(cdev, "delayed_status count %d\n",
 808                                         cdev->delayed_status);
 809                 }
 810         }
 811
 812         /* when we return, be sure our power usage is valid */
 813         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 814 done:
 815         usb_gadget_vbus_draw(gadget, power);
 816         if (result >= 0 && cdev->delayed_status)
 817                 result = USB_GADGET_DELAYED_STATUS;
 818         return result;
 819 }
 820
 821 int usb_add_config_only(struct usb_composite_dev *cdev,
 822                 struct usb_configuration *config)
 823 {
 824         struct usb_configuration *c;
 825
 826         if (!config->bConfigurationValue)
 827                 return -EINVAL;
 828
 829         /* Prevent duplicate configuration identifiers */
 830         list_for_each_entry(c, &cdev->configs, list) {
 831                 if (c->bConfigurationValue == config->bConfigurationValue)
 832                         return -EBUSY;
 833         }
 834
 835         config->cdev = cdev;
 836         list_add_tail(&config->list, &cdev->configs);
 837
 838         INIT_LIST_HEAD(&config->functions);
 839         config->next_interface_id = 0;
 840         memset(config->interface, 0, sizeof(config->interface));
 841
 842         return 0;
 843 }
 844 EXPORT_SYMBOL_GPL(usb_add_config_only);
 845
 846 /**
 847  * usb_add_config() - add a configuration to a device.
 848  * @cdev: wraps the USB gadget
 849  * @config: the configuration, with bConfigurationValue assigned
 850  * @bind: the configuration's bind function
 851  * Context: single threaded during gadget setup
 852  *
 853  * One of the main tasks of a composite @bind() routine is to
 854  * add each of the configurations it supports, using this routine.
 855  *
 856  * This function returns the value of the configuration's @bind(), which
 857  * is zero for success else a negative errno value.  Binding configurations
 858  * assigns global resources including string IDs, and per-configuration
 859  * resources such as interface IDs and endpoints.
 860  */
 861 int usb_add_config(struct usb_composite_dev *cdev,
 862                 struct usb_configuration *config,
 863                 int (*bind)(struct usb_configuration *))
 864 {
 865         int                             status = -EINVAL;
 866
 867         if (!bind)
 868                 goto done;
 869
 870         DBG(cdev, "adding config #%u '%s'/%p\n",
 871                         config->bConfigurationValue,
 872                         config->label, config);
 873
 874         status = usb_add_config_only(cdev, config);
 875         if (status)
 876                 goto done;
 877
 878         status = bind(config);
 879         if (status < 0) {
 880                 while (!list_empty(&config->functions)) {
 881                         struct usb_function             *f;
 882
 883                         f = list_first_entry(&config->functions,
 884                                         struct usb_function, list);
 885                         list_del(&f->list);
 886                         if (f->unbind) {
 887                                 DBG(cdev, "unbind function '%s'/%p\n",
 888                                         f->name, f);
 889                                 f->unbind(config, f);
 890                                 /* may free memory for "f" */
 891                         }
 892                 }
 893                 list_del(&config->list);
 894                 config->cdev = NULL;
 895         } else {
 896                 unsigned        i;
 897
 898                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
 899                         config->bConfigurationValue, config,
 900                         config->superspeed_plus ? " superplus" : "",
 901                         config->superspeed ? " super" : "",
 902                         config->highspeed ? " high" : "",
 903                         config->fullspeed
 904                                 ? (gadget_is_dualspeed(cdev->gadget)
 905                                         ? " full"
 906                                         : " full/low")
 907                                 : "");
 908
 909                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 910                         struct usb_function     *f = config->interface[i];
 911
 912                         if (!f)
 913                                 continue;
 914                         DBG(cdev, "  interface %d = %s/%p\n",
 915                                 i, f->name, f);
 916                 }
 917         }
 918
 919         /* set_alt(), or next bind(), sets up ep->claimed as needed */
 920         usb_ep_autoconfig_reset(cdev->gadget);
 921
 922 done:
 923         if (status)
 924                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 925                                 config->bConfigurationValue, status);
 926         return status;
 927 }
 928 EXPORT_SYMBOL_GPL(usb_add_config);
 929
 930 static void remove_config(struct usb_composite_dev *cdev,
 931                               struct usb_configuration *config)
 932 {
 933         while (!list_empty(&config->functions)) {
 934                 struct usb_function             *f;
 935
 936                 f = list_first_entry(&config->functions,
 937                                 struct usb_function, list);
 938                 list_del(&f->list);
 939                 if (f->unbind) {
 940                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 941                         f->unbind(config, f);
 942                         /* may free memory for "f" */
 943                 }
 944         }
 945         list_del(&config->list);
 946         if (config->unbind) {
 947                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 948                 config->unbind(config);
 949                         /* may free memory for "c" */
 950         }
 951 }
 952
 953 /**
 954  * usb_remove_config() - remove a configuration from a device.
 955  * @cdev: wraps the USB gadget
 956  * @config: the configuration
 957  *
 958  * Drivers must call usb_gadget_disconnect before calling this function
 959  * to disconnect the device from the host and make sure the host will not
 960  * try to enumerate the device while we are changing the config list.
 961  */
 962 void usb_remove_config(struct usb_composite_dev *cdev,
 963                       struct usb_configuration *config)
 964 {
 965         unsigned long flags;
 966
 967         spin_lock_irqsave(&cdev->lock, flags);
 968
 969         if (cdev->config == config)
 970                 reset_config(cdev);
 971
 972         spin_unlock_irqrestore(&cdev->lock, flags);
 973
 974         remove_config(cdev, config);
 975 }
 976
 977 /*-------------------------------------------------------------------------*/
 978
 979 /* We support strings in multiple languages ... string descriptor zero
 980  * says which languages are supported.  The typical case will be that
 981  * only one language (probably English) is used, with i18n handled on
 982  * the host side.
 983  */
 984
 985 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 986 {
 987         const struct usb_gadget_strings *s;
 988         __le16                          language;
 989         __le16                          *tmp;
 990
 991         while (*sp) {
 992                 s = *sp;
 993                 language = cpu_to_le16(s->language);
 994                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 995                         if (*tmp == language)
 996                                 goto repeat;
 997                 }
 998                 *tmp++ = language;
 999 repeat:
1000                 sp++;
1001         }
1002 }
1003
1004 static int lookup_string(
1005         struct usb_gadget_strings       **sp,
1006         void                            *buf,
1007         u16                             language,
1008         int                             id
1009 )
1010 {
1011         struct usb_gadget_strings       *s;
1012         int                             value;
1013
1014         while (*sp) {
1015                 s = *sp++;
1016                 if (s->language != language)
1017                         continue;
1018                 value = usb_gadget_get_string(s, id, buf);
1019                 if (value > 0)
1020                         return value;
1021         }
1022         return -EINVAL;
1023 }
1024
1025 static int get_string(struct usb_composite_dev *cdev,
1026                 void *buf, u16 language, int id)
1027 {
1028         struct usb_composite_driver     *composite = cdev->driver;
1029         struct usb_gadget_string_container *uc;
1030         struct usb_configuration        *c;
1031         struct usb_function             *f;
1032         int                             len;
1033
1034         /* Yes, not only is USB's i18n support probably more than most
1035          * folk will ever care about ... also, it's all supported here.
1036          * (Except for UTF8 support for Unicode's "Astral Planes".)
1037          */
1038
1039         /* 0 == report all available language codes */
1040         if (id == 0) {
1041                 struct usb_string_descriptor    *s = buf;
1042                 struct usb_gadget_strings       **sp;
1043
1044                 memset(s, 0, 256);
1045                 s->bDescriptorType = USB_DT_STRING;
1046
1047                 sp = composite->strings;
1048                 if (sp)
1049                         collect_langs(sp, s->wData);
1050
1051                 list_for_each_entry(c, &cdev->configs, list) {
1052                         sp = c->strings;
1053                         if (sp)
1054                                 collect_langs(sp, s->wData);
1055
1056                         list_for_each_entry(f, &c->functions, list) {
1057                                 sp = f->strings;
1058                                 if (sp)
1059                                         collect_langs(sp, s->wData);
1060                         }
1061                 }
1062                 list_for_each_entry(uc, &cdev->gstrings, list) {
1063                         struct usb_gadget_strings **sp;
1064
1065                         sp = get_containers_gs(uc);
1066                         collect_langs(sp, s->wData);
1067                 }
1068
1069                 for (len = 0; len <= 126 && s->wData[len]; len++)
1070                         continue;
1071                 if (!len)
1072                         return -EINVAL;
1073
1074                 s->bLength = 2 * (len + 1);
1075                 return s->bLength;
1076         }
1077
1078         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1079                 struct usb_os_string *b = buf;
1080                 b->bLength = sizeof(*b);
1081                 b->bDescriptorType = USB_DT_STRING;
1082                 compiletime_assert(
1083                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1084                         "qwSignature size must be equal to qw_sign");
1085                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1086                 b->bMS_VendorCode = cdev->b_vendor_code;
1087                 b->bPad = 0;
1088                 return sizeof(*b);
1089         }
1090
1091         list_for_each_entry(uc, &cdev->gstrings, list) {
1092                 struct usb_gadget_strings **sp;
1093
1094                 sp = get_containers_gs(uc);
1095                 len = lookup_string(sp, buf, language, id);
1096                 if (len > 0)
1097                         return len;
1098         }
1099
1100         /* String IDs are device-scoped, so we look up each string
1101          * table we're told about.  These lookups are infrequent;
1102          * simpler-is-better here.
1103          */
1104         if (composite->strings) {
1105                 len = lookup_string(composite->strings, buf, language, id);
1106                 if (len > 0)
1107                         return len;
1108         }
1109         list_for_each_entry(c, &cdev->configs, list) {
1110                 if (c->strings) {
1111                         len = lookup_string(c->strings, buf, language, id);
1112                         if (len > 0)
1113                                 return len;
1114                 }
1115                 list_for_each_entry(f, &c->functions, list) {
1116                         if (!f->strings)
1117                                 continue;
1118                         len = lookup_string(f->strings, buf, language, id);
1119                         if (len > 0)
1120                                 return len;
1121                 }
1122         }
1123         return -EINVAL;
1124 }
1125
1126 /**
1127  * usb_string_id() - allocate an unused string ID
1128  * @cdev: the device whose string descriptor IDs are being allocated
1129  * Context: single threaded during gadget setup
1130  *
1131  * @usb_string_id() is called from bind() callbacks to allocate
1132  * string IDs.  Drivers for functions, configurations, or gadgets will
1133  * then store that ID in the appropriate descriptors and string table.
1134  *
1135  * All string identifier should be allocated using this,
1136  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1137  * that for example different functions don't wrongly assign different
1138  * meanings to the same identifier.
1139  */
1140 int usb_string_id(struct usb_composite_dev *cdev)
1141 {
1142         if (cdev->next_string_id < 254) {
1143                 /* string id 0 is reserved by USB spec for list of
1144                  * supported languages */
1145                 /* 255 reserved as well? -- mina86 */
1146                 cdev->next_string_id++;
1147                 return cdev->next_string_id;
1148         }
1149         return -ENODEV;
1150 }
1151 EXPORT_SYMBOL_GPL(usb_string_id);
1152
1153 /**
1154  * usb_string_ids() - allocate unused string IDs in batch
1155  * @cdev: the device whose string descriptor IDs are being allocated
1156  * @str: an array of usb_string objects to assign numbers to
1157  * Context: single threaded during gadget setup
1158  *
1159  * @usb_string_ids() is called from bind() callbacks to allocate
1160  * string IDs.  Drivers for functions, configurations, or gadgets will
1161  * then copy IDs from the string table to the appropriate descriptors
1162  * and string table for other languages.
1163  *
1164  * All string identifier should be allocated using this,
1165  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1166  * example different functions don't wrongly assign different meanings
1167  * to the same identifier.
1168  */
1169 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1170 {
1171         int next = cdev->next_string_id;
1172
1173         for (; str->s; ++str) {
1174                 if (unlikely(next >= 254))
1175                         return -ENODEV;
1176                 str->id = ++next;
1177         }
1178
1179         cdev->next_string_id = next;
1180
1181         return 0;
1182 }
1183 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1184
1185 static struct usb_gadget_string_container *copy_gadget_strings(
1186                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1187                 unsigned n_strings)
1188 {
1189         struct usb_gadget_string_container *uc;
1190         struct usb_gadget_strings **gs_array;
1191         struct usb_gadget_strings *gs;
1192         struct usb_string *s;
1193         unsigned mem;
1194         unsigned n_gs;
1195         unsigned n_s;
1196         void *stash;
1197
1198         mem = sizeof(*uc);
1199         mem += sizeof(void *) * (n_gstrings + 1);
1200         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1201         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1202         uc = kmalloc(mem, GFP_KERNEL);
1203         if (!uc)
1204                 return ERR_PTR(-ENOMEM);
1205         gs_array = get_containers_gs(uc);
1206         stash = uc->stash;
1207         stash += sizeof(void *) * (n_gstrings + 1);
1208         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1209                 struct usb_string *org_s;
1210
1211                 gs_array[n_gs] = stash;
1212                 gs = gs_array[n_gs];
1213                 stash += sizeof(struct usb_gadget_strings);
1214                 gs->language = sp[n_gs]->language;
1215                 gs->strings = stash;
1216                 org_s = sp[n_gs]->strings;
1217
1218                 for (n_s = 0; n_s < n_strings; n_s++) {
1219                         s = stash;
1220                         stash += sizeof(struct usb_string);
1221                         if (org_s->s)
1222                                 s->s = org_s->s;
1223                         else
1224                                 s->s = "";
1225                         org_s++;
1226                 }
1227                 s = stash;
1228                 s->s = NULL;
1229                 stash += sizeof(struct usb_string);
1230
1231         }
1232         gs_array[n_gs] = NULL;
1233         return uc;
1234 }
1235
1236 /**
1237  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1238  * @cdev: the device whose string descriptor IDs are being allocated
1239  * and attached.
1240  * @sp: an array of usb_gadget_strings to attach.
1241  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1242  *
1243  * This function will create a deep copy of usb_gadget_strings and usb_string
1244  * and attach it to the cdev. The actual string (usb_string.s) will not be
1245  * copied but only a referenced will be made. The struct usb_gadget_strings
1246  * array may contain multiple languages and should be NULL terminated.
1247  * The ->language pointer of each struct usb_gadget_strings has to contain the
1248  * same amount of entries.
1249  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1250  * usb_string entry of es-ES contains the translation of the first usb_string
1251  * entry of en-US. Therefore both entries become the same id assign.
1252  */
1253 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1254                 struct usb_gadget_strings **sp, unsigned n_strings)
1255 {
1256         struct usb_gadget_string_container *uc;
1257         struct usb_gadget_strings **n_gs;
1258         unsigned n_gstrings = 0;
1259         unsigned i;
1260         int ret;
1261
1262         for (i = 0; sp[i]; i++)
1263                 n_gstrings++;
1264
1265         if (!n_gstrings)
1266                 return ERR_PTR(-EINVAL);
1267
1268         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1269         if (IS_ERR(uc))
1270                 return ERR_CAST(uc);
1271
1272         n_gs = get_containers_gs(uc);
1273         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1274         if (ret)
1275                 goto err;
1276
1277         for (i = 1; i < n_gstrings; i++) {
1278                 struct usb_string *m_s;
1279                 struct usb_string *s;
1280                 unsigned n;
1281
1282                 m_s = n_gs[0]->strings;
1283                 s = n_gs[i]->strings;
1284                 for (n = 0; n < n_strings; n++) {
1285                         s->id = m_s->id;
1286                         s++;
1287                         m_s++;
1288                 }
1289         }
1290         list_add_tail(&uc->list, &cdev->gstrings);
1291         return n_gs[0]->strings;
1292 err:
1293         kfree(uc);
1294         return ERR_PTR(ret);
1295 }
1296 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1297
1298 /**
1299  * usb_string_ids_n() - allocate unused string IDs in batch
1300  * @c: the device whose string descriptor IDs are being allocated
1301  * @n: number of string IDs to allocate
1302  * Context: single threaded during gadget setup
1303  *
1304  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1305  * valid IDs.  At least provided that @n is non-zero because if it
1306  * is, returns last requested ID which is now very useful information.
1307  *
1308  * @usb_string_ids_n() is called from bind() callbacks to allocate
1309  * string IDs.  Drivers for functions, configurations, or gadgets will
1310  * then store that ID in the appropriate descriptors and string table.
1311  *
1312  * All string identifier should be allocated using this,
1313  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1314  * example different functions don't wrongly assign different meanings
1315  * to the same identifier.
1316  */
1317 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1318 {
1319         unsigned next = c->next_string_id;
1320         if (unlikely(n > 254 || (unsigned)next + n > 254))
1321                 return -ENODEV;
1322         c->next_string_id += n;
1323         return next + 1;
1324 }
1325 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1326
1327 /*-------------------------------------------------------------------------*/
1328
1329 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1330 {
1331         struct usb_composite_dev *cdev;
1332
1333         if (req->status || req->actual != req->length)
1334                 DBG((struct usb_composite_dev *) ep->driver_data,
1335                                 "setup complete --> %d, %d/%d\n",
1336                                 req->status, req->actual, req->length);
1337
1338         /*
1339          * REVIST The same ep0 requests are shared with function drivers
1340          * so they don't have to maintain the same ->complete() stubs.
1341          *
1342          * Because of that, we need to check for the validity of ->context
1343          * here, even though we know we've set it to something useful.
1344          */
1345         if (!req->context)
1346                 return;
1347
1348         cdev = req->context;
1349
1350         if (cdev->req == req)
1351                 cdev->setup_pending = false;
1352         else if (cdev->os_desc_req == req)
1353                 cdev->os_desc_pending = false;
1354         else
1355                 WARN(1, "unknown request %p\n", req);
1356 }
1357
1358 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1359                 struct usb_request *req, gfp_t gfp_flags)
1360 {
1361         int ret;
1362
1363         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1364         if (ret == 0) {
1365                 if (cdev->req == req)
1366                         cdev->setup_pending = true;
1367                 else if (cdev->os_desc_req == req)
1368                         cdev->os_desc_pending = true;
1369                 else
1370                         WARN(1, "unknown request %p\n", req);
1371         }
1372
1373         return ret;
1374 }
1375
1376 static int count_ext_compat(struct usb_configuration *c)
1377 {
1378         int i, res;
1379
1380         res = 0;
1381         for (i = 0; i < c->next_interface_id; ++i) {
1382                 struct usb_function *f;
1383                 int j;
1384
1385                 f = c->interface[i];
1386                 for (j = 0; j < f->os_desc_n; ++j) {
1387                         struct usb_os_desc *d;
1388
1389                         if (i != f->os_desc_table[j].if_id)
1390                                 continue;
1391                         d = f->os_desc_table[j].os_desc;
1392                         if (d && d->ext_compat_id)
1393                                 ++res;
1394                 }
1395         }
1396         BUG_ON(res > 255);
1397         return res;
1398 }
1399
1400 static void fill_ext_compat(struct usb_configuration *c, u8 *buf)
1401 {
1402         int i, count;
1403
1404         count = 16;
1405         for (i = 0; i < c->next_interface_id; ++i) {
1406                 struct usb_function *f;
1407                 int j;
1408
1409                 f = c->interface[i];
1410                 for (j = 0; j < f->os_desc_n; ++j) {
1411                         struct usb_os_desc *d;
1412
1413                         if (i != f->os_desc_table[j].if_id)
1414                                 continue;
1415                         d = f->os_desc_table[j].os_desc;
1416                         if (d && d->ext_compat_id) {
1417                                 *buf++ = i;
1418                                 *buf++ = 0x01;
1419                                 memcpy(buf, d->ext_compat_id, 16);
1420                                 buf += 22;
1421                         } else {
1422                                 ++buf;
1423                                 *buf = 0x01;
1424                                 buf += 23;
1425                         }
1426                         count += 24;
1427                         if (count >= 4096)
1428                                 return;
1429                 }
1430         }
1431 }
1432
1433 static int count_ext_prop(struct usb_configuration *c, int interface)
1434 {
1435         struct usb_function *f;
1436         int j;
1437
1438         f = c->interface[interface];
1439         for (j = 0; j < f->os_desc_n; ++j) {
1440                 struct usb_os_desc *d;
1441
1442                 if (interface != f->os_desc_table[j].if_id)
1443                         continue;
1444                 d = f->os_desc_table[j].os_desc;
1445                 if (d && d->ext_compat_id)
1446                         return d->ext_prop_count;
1447         }
1448         return 0;
1449 }
1450
1451 static int len_ext_prop(struct usb_configuration *c, int interface)
1452 {
1453         struct usb_function *f;
1454         struct usb_os_desc *d;
1455         int j, res;
1456
1457         res = 10; /* header length */
1458         f = c->interface[interface];
1459         for (j = 0; j < f->os_desc_n; ++j) {
1460                 if (interface != f->os_desc_table[j].if_id)
1461                         continue;
1462                 d = f->os_desc_table[j].os_desc;
1463                 if (d)
1464                         return min(res + d->ext_prop_len, 4096);
1465         }
1466         return res;
1467 }
1468
1469 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1470 {
1471         struct usb_function *f;
1472         struct usb_os_desc *d;
1473         struct usb_os_desc_ext_prop *ext_prop;
1474         int j, count, n, ret;
1475         u8 *start = buf;
1476
1477         f = c->interface[interface];
1478         for (j = 0; j < f->os_desc_n; ++j) {
1479                 if (interface != f->os_desc_table[j].if_id)
1480                         continue;
1481                 d = f->os_desc_table[j].os_desc;
1482                 if (d)
1483                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1484                                 /* 4kB minus header length */
1485                                 n = buf - start;
1486                                 if (n >= 4086)
1487                                         return 0;
1488
1489                                 count = ext_prop->data_len +
1490                                         ext_prop->name_len + 14;
1491                                 if (count > 4086 - n)
1492                                         return -EINVAL;
1493                                 usb_ext_prop_put_size(buf, count);
1494                                 usb_ext_prop_put_type(buf, ext_prop->type);
1495                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1496                                                             ext_prop->name_len);
1497                                 if (ret < 0)
1498                                         return ret;
1499                                 switch (ext_prop->type) {
1500                                 case USB_EXT_PROP_UNICODE:
1501                                 case USB_EXT_PROP_UNICODE_ENV:
1502                                 case USB_EXT_PROP_UNICODE_LINK:
1503                                         usb_ext_prop_put_unicode(buf, ret,
1504                                                          ext_prop->data,
1505                                                          ext_prop->data_len);
1506                                         break;
1507                                 case USB_EXT_PROP_BINARY:
1508                                         usb_ext_prop_put_binary(buf, ret,
1509                                                         ext_prop->data,
1510                                                         ext_prop->data_len);
1511                                         break;
1512                                 case USB_EXT_PROP_LE32:
1513                                         /* not implemented */
1514                                 case USB_EXT_PROP_BE32:
1515                                         /* not implemented */
1516                                 default:
1517                                         return -EINVAL;
1518                                 }
1519                                 buf += count;
1520                         }
1521         }
1522
1523         return 0;
1524 }
1525
1526 /*
1527  * The setup() callback implements all the ep0 functionality that's
1528  * not handled lower down, in hardware or the hardware driver(like
1529  * device and endpoint feature flags, and their status).  It's all
1530  * housekeeping for the gadget function we're implementing.  Most of
1531  * the work is in config and function specific setup.
1532  */
1533 int
1534 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1535 {
1536         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1537         struct usb_request              *req = cdev->req;
1538         int                             value = -EOPNOTSUPP;
1539         int                             status = 0;
1540         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1541         u8                              intf = w_index & 0xFF;
1542         u16                             w_value = le16_to_cpu(ctrl->wValue);
1543         u16                             w_length = le16_to_cpu(ctrl->wLength);
1544         struct usb_function             *f = NULL;
1545         u8                              endp;
1546
1547         /* partial re-init of the response message; the function or the
1548          * gadget might need to intercept e.g. a control-OUT completion
1549          * when we delegate to it.
1550          */
1551         req->zero = 0;
1552         req->context = cdev;
1553         req->complete = composite_setup_complete;
1554         req->length = 0;
1555         gadget->ep0->driver_data = cdev;
1556
1557         /*
1558          * Don't let non-standard requests match any of the cases below
1559          * by accident.
1560          */
1561         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1562                 goto unknown;
1563
1564         switch (ctrl->bRequest) {
1565
1566         /* we handle all standard USB descriptors */
1567         case USB_REQ_GET_DESCRIPTOR:
1568                 if (ctrl->bRequestType != USB_DIR_IN)
1569                         goto unknown;
1570                 switch (w_value >> 8) {
1571
1572                 case USB_DT_DEVICE:
1573                         cdev->desc.bNumConfigurations =
1574                                 count_configs(cdev, USB_DT_DEVICE);
1575                         cdev->desc.bMaxPacketSize0 =
1576                                 cdev->gadget->ep0->maxpacket;
1577                         if (gadget_is_superspeed(gadget)) {
1578                                 if (gadget->speed >= USB_SPEED_SUPER) {
1579                                         cdev->desc.bcdUSB = cpu_to_le16(0x0310);
1580                                         cdev->desc.bMaxPacketSize0 = 9;
1581                                 } else {
1582                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1583                                 }
1584                         } else {
1585                                 cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1586                         }
1587
1588                         value = min(w_length, (u16) sizeof cdev->desc);
1589                         memcpy(req->buf, &cdev->desc, value);
1590                         break;
1591                 case USB_DT_DEVICE_QUALIFIER:
1592                         if (!gadget_is_dualspeed(gadget) ||
1593                             gadget->speed >= USB_SPEED_SUPER)
1594                                 break;
1595                         device_qual(cdev);
1596                         value = min_t(int, w_length,
1597                                 sizeof(struct usb_qualifier_descriptor));
1598                         break;
1599                 case USB_DT_OTHER_SPEED_CONFIG:
1600                         if (!gadget_is_dualspeed(gadget) ||
1601                             gadget->speed >= USB_SPEED_SUPER)
1602                                 break;
1603                         /* FALLTHROUGH */
1604                 case USB_DT_CONFIG:
1605                         value = config_desc(cdev, w_value);
1606                         if (value >= 0)
1607                                 value = min(w_length, (u16) value);
1608                         break;
1609                 case USB_DT_STRING:
1610                         value = get_string(cdev, req->buf,
1611                                         w_index, w_value & 0xff);
1612                         if (value >= 0)
1613                                 value = min(w_length, (u16) value);
1614                         break;
1615                 case USB_DT_BOS:
1616                         if (gadget_is_superspeed(gadget)) {
1617                                 value = bos_desc(cdev);
1618                                 value = min(w_length, (u16) value);
1619                         }
1620                         break;
1621                 case USB_DT_OTG:
1622                         if (gadget_is_otg(gadget)) {
1623                                 struct usb_configuration *config;
1624                                 int otg_desc_len = 0;
1625
1626                                 if (cdev->config)
1627                                         config = cdev->config;
1628                                 else
1629                                         config = list_first_entry(
1630                                                         &cdev->configs,
1631                                                 struct usb_configuration, list);
1632                                 if (!config)
1633                                         goto done;
1634
1635                                 if (gadget->otg_caps &&
1636                                         (gadget->otg_caps->otg_rev >= 0x0200))
1637                                         otg_desc_len += sizeof(
1638                                                 struct usb_otg20_descriptor);
1639                                 else
1640                                         otg_desc_len += sizeof(
1641                                                 struct usb_otg_descriptor);
1642
1643                                 value = min_t(int, w_length, otg_desc_len);
1644                                 memcpy(req->buf, config->descriptors[0], value);
1645                         }
1646                         break;
1647                 }
1648                 break;
1649
1650         /* any number of configs can work */
1651         case USB_REQ_SET_CONFIGURATION:
1652                 if (ctrl->bRequestType != 0)
1653                         goto unknown;
1654                 if (gadget_is_otg(gadget)) {
1655                         if (gadget->a_hnp_support)
1656                                 DBG(cdev, "HNP available\n");
1657                         else if (gadget->a_alt_hnp_support)
1658                                 DBG(cdev, "HNP on another port\n");
1659                         else
1660                                 VDBG(cdev, "HNP inactive\n");
1661                 }
1662                 spin_lock(&cdev->lock);
1663                 value = set_config(cdev, ctrl, w_value);
1664                 spin_unlock(&cdev->lock);
1665                 break;
1666         case USB_REQ_GET_CONFIGURATION:
1667                 if (ctrl->bRequestType != USB_DIR_IN)
1668                         goto unknown;
1669                 if (cdev->config)
1670                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1671                 else
1672                         *(u8 *)req->buf = 0;
1673                 value = min(w_length, (u16) 1);
1674                 break;
1675
1676         /* function drivers must handle get/set altsetting; if there's
1677          * no get() method, we know only altsetting zero works.
1678          */
1679         case USB_REQ_SET_INTERFACE:
1680                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1681                         goto unknown;
1682                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1683                         break;
1684                 f = cdev->config->interface[intf];
1685                 if (!f)
1686                         break;
1687                 if (w_value && !f->set_alt)
1688                         break;
1689                 value = f->set_alt(f, w_index, w_value);
1690                 if (value == USB_GADGET_DELAYED_STATUS) {
1691                         DBG(cdev,
1692                          "%s: interface %d (%s) requested delayed status\n",
1693                                         __func__, intf, f->name);
1694                         cdev->delayed_status++;
1695                         DBG(cdev, "delayed_status count %d\n",
1696                                         cdev->delayed_status);
1697                 }
1698                 break;
1699         case USB_REQ_GET_INTERFACE:
1700                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1701                         goto unknown;
1702                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1703                         break;
1704                 f = cdev->config->interface[intf];
1705                 if (!f)
1706                         break;
1707                 /* lots of interfaces only need altsetting zero... */
1708                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1709                 if (value < 0)
1710                         break;
1711                 *((u8 *)req->buf) = value;
1712                 value = min(w_length, (u16) 1);
1713                 break;
1714         case USB_REQ_GET_STATUS:
1715                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1716                                                 (w_index == OTG_STS_SELECTOR)) {
1717                         if (ctrl->bRequestType != (USB_DIR_IN |
1718                                                         USB_RECIP_DEVICE))
1719                                 goto unknown;
1720                         *((u8 *)req->buf) = gadget->host_request_flag;
1721                         value = 1;
1722                         break;
1723                 }
1724
1725                 /*
1726                  * USB 3.0 additions:
1727                  * Function driver should handle get_status request. If such cb
1728                  * wasn't supplied we respond with default value = 0
1729                  * Note: function driver should supply such cb only for the
1730                  * first interface of the function
1731                  */
1732                 if (!gadget_is_superspeed(gadget))
1733                         goto unknown;
1734                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1735                         goto unknown;
1736                 value = 2;      /* This is the length of the get_status reply */
1737                 put_unaligned_le16(0, req->buf);
1738                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1739                         break;
1740                 f = cdev->config->interface[intf];
1741                 if (!f)
1742                         break;
1743                 status = f->get_status ? f->get_status(f) : 0;
1744                 if (status < 0)
1745                         break;
1746                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1747                 break;
1748         /*
1749          * Function drivers should handle SetFeature/ClearFeature
1750          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1751          * only for the first interface of the function
1752          */
1753         case USB_REQ_CLEAR_FEATURE:
1754         case USB_REQ_SET_FEATURE:
1755                 if (!gadget_is_superspeed(gadget))
1756                         goto unknown;
1757                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1758                         goto unknown;
1759                 switch (w_value) {
1760                 case USB_INTRF_FUNC_SUSPEND:
1761                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1762                                 break;
1763                         f = cdev->config->interface[intf];
1764                         if (!f)
1765                                 break;
1766                         value = 0;
1767                         if (f->func_suspend)
1768                                 value = f->func_suspend(f, w_index >> 8);
1769                         if (value < 0) {
1770                                 ERROR(cdev,
1771                                       "func_suspend() returned error %d\n",
1772                                       value);
1773                                 value = 0;
1774                         }
1775                         break;
1776                 }
1777                 break;
1778         default:
1779 unknown:
1780                 /*
1781                  * OS descriptors handling
1782                  */
1783                 if (cdev->use_os_string && cdev->os_desc_config &&
1784                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1785                     ctrl->bRequest == cdev->b_vendor_code) {
1786                         struct usb_request              *req;
1787                         struct usb_configuration        *os_desc_cfg;
1788                         u8                              *buf;
1789                         int                             interface;
1790                         int                             count = 0;
1791
1792                         req = cdev->os_desc_req;
1793                         req->context = cdev;
1794                         req->complete = composite_setup_complete;
1795                         buf = req->buf;
1796                         os_desc_cfg = cdev->os_desc_config;
1797                         memset(buf, 0, w_length);
1798                         buf[5] = 0x01;
1799                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1800                         case USB_RECIP_DEVICE:
1801                                 if (w_index != 0x4 || (w_value >> 8))
1802                                         break;
1803                                 buf[6] = w_index;
1804                                 if (w_length == 0x10) {
1805                                         /* Number of ext compat interfaces */
1806                                         count = count_ext_compat(os_desc_cfg);
1807                                         buf[8] = count;
1808                                         count *= 24; /* 24 B/ext compat desc */
1809                                         count += 16; /* header */
1810                                         put_unaligned_le32(count, buf);
1811                                         value = w_length;
1812                                 } else {
1813                                         /* "extended compatibility ID"s */
1814                                         count = count_ext_compat(os_desc_cfg);
1815                                         buf[8] = count;
1816                                         count *= 24; /* 24 B/ext compat desc */
1817                                         count += 16; /* header */
1818                                         put_unaligned_le32(count, buf);
1819                                         buf += 16;
1820                                         fill_ext_compat(os_desc_cfg, buf);
1821                                         value = w_length;
1822                                 }
1823                                 break;
1824                         case USB_RECIP_INTERFACE:
1825                                 if (w_index != 0x5 || (w_value >> 8))
1826                                         break;
1827                                 interface = w_value & 0xFF;
1828                                 buf[6] = w_index;
1829                                 if (w_length == 0x0A) {
1830                                         count = count_ext_prop(os_desc_cfg,
1831                                                 interface);
1832                                         put_unaligned_le16(count, buf + 8);
1833                                         count = len_ext_prop(os_desc_cfg,
1834                                                 interface);
1835                                         put_unaligned_le32(count, buf);
1836
1837                                         value = w_length;
1838                                 } else {
1839                                         count = count_ext_prop(os_desc_cfg,
1840                                                 interface);
1841                                         put_unaligned_le16(count, buf + 8);
1842                                         count = len_ext_prop(os_desc_cfg,
1843                                                 interface);
1844                                         put_unaligned_le32(count, buf);
1845                                         buf += 10;
1846                                         value = fill_ext_prop(os_desc_cfg,
1847                                                               interface, buf);
1848                                         if (value < 0)
1849                                                 return value;
1850
1851                                         value = w_length;
1852                                 }
1853                                 break;
1854                         }
1855                         req->length = value;
1856                         req->context = cdev;
1857                         req->zero = value < w_length;
1858                         value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1859                         if (value < 0) {
1860                                 DBG(cdev, "ep_queue --> %d\n", value);
1861                                 req->status = 0;
1862                                 composite_setup_complete(gadget->ep0, req);
1863                         }
1864                         return value;
1865                 }
1866
1867                 VDBG(cdev,
1868                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1869                         ctrl->bRequestType, ctrl->bRequest,
1870                         w_value, w_index, w_length);
1871
1872                 /* functions always handle their interfaces and endpoints...
1873                  * punt other recipients (other, WUSB, ...) to the current
1874                  * configuration code.
1875                  *
1876                  * REVISIT it could make sense to let the composite device
1877                  * take such requests too, if that's ever needed:  to work
1878                  * in config 0, etc.
1879                  */
1880                 if (cdev->config) {
1881                         list_for_each_entry(f, &cdev->config->functions, list)
1882                                 if (f->req_match && f->req_match(f, ctrl))
1883                                         goto try_fun_setup;
1884                         f = NULL;
1885                 }
1886
1887                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1888                 case USB_RECIP_INTERFACE:
1889                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1890                                 break;
1891                         f = cdev->config->interface[intf];
1892                         break;
1893
1894                 case USB_RECIP_ENDPOINT:
1895                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1896                         list_for_each_entry(f, &cdev->config->functions, list) {
1897                                 if (test_bit(endp, f->endpoints))
1898                                         break;
1899                         }
1900                         if (&f->list == &cdev->config->functions)
1901                                 f = NULL;
1902                         break;
1903                 }
1904 try_fun_setup:
1905                 if (f && f->setup)
1906                         value = f->setup(f, ctrl);
1907                 else {
1908                         struct usb_configuration        *c;
1909
1910                         c = cdev->config;
1911                         if (!c)
1912                                 goto done;
1913
1914                         /* try current config's setup */
1915                         if (c->setup) {
1916                                 value = c->setup(c, ctrl);
1917                                 goto done;
1918                         }
1919
1920                         /* try the only function in the current config */
1921                         if (!list_is_singular(&c->functions))
1922                                 goto done;
1923                         f = list_first_entry(&c->functions, struct usb_function,
1924                                              list);
1925                         if (f->setup)
1926                                 value = f->setup(f, ctrl);
1927                 }
1928
1929                 goto done;
1930         }
1931
1932         /* respond with data transfer before status phase? */
1933         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1934                 req->length = value;
1935                 req->context = cdev;
1936                 req->zero = value < w_length;
1937                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1938                 if (value < 0) {
1939                         DBG(cdev, "ep_queue --> %d\n", value);
1940                         req->status = 0;
1941                         composite_setup_complete(gadget->ep0, req);
1942                 }
1943         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1944                 WARN(cdev,
1945                         "%s: Delayed status not supported for w_length != 0",
1946                         __func__);
1947         }
1948
1949 done:
1950         /* device either stalls (value < 0) or reports success */
1951         return value;
1952 }
1953
1954 void composite_disconnect(struct usb_gadget *gadget)
1955 {
1956         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1957         unsigned long                   flags;
1958
1959         /* REVISIT:  should we have config and device level
1960          * disconnect callbacks?
1961          */
1962         spin_lock_irqsave(&cdev->lock, flags);
1963         if (cdev->config)
1964                 reset_config(cdev);
1965         if (cdev->driver->disconnect)
1966                 cdev->driver->disconnect(cdev);
1967         spin_unlock_irqrestore(&cdev->lock, flags);
1968 }
1969
1970 /*-------------------------------------------------------------------------*/
1971
1972 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
1973                               char *buf)
1974 {
1975         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1976         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1977
1978         return sprintf(buf, "%d\n", cdev->suspended);
1979 }
1980 static DEVICE_ATTR_RO(suspended);
1981
1982 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1983 {
1984         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1985
1986         /* composite_disconnect() must already have been called
1987          * by the underlying peripheral controller driver!
1988          * so there's no i/o concurrency that could affect the
1989          * state protected by cdev->lock.
1990          */
1991         WARN_ON(cdev->config);
1992
1993         while (!list_empty(&cdev->configs)) {
1994                 struct usb_configuration        *c;
1995                 c = list_first_entry(&cdev->configs,
1996                                 struct usb_configuration, list);
1997                 remove_config(cdev, c);
1998         }
1999         if (cdev->driver->unbind && unbind_driver)
2000                 cdev->driver->unbind(cdev);
2001
2002         composite_dev_cleanup(cdev);
2003
2004         kfree(cdev->def_manufacturer);
2005         kfree(cdev);
2006         set_gadget_data(gadget, NULL);
2007 }
2008
2009 static void composite_unbind(struct usb_gadget *gadget)
2010 {
2011         __composite_unbind(gadget, true);
2012 }
2013
2014 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2015                 const struct usb_device_descriptor *old)
2016 {
2017         __le16 idVendor;
2018         __le16 idProduct;
2019         __le16 bcdDevice;
2020         u8 iSerialNumber;
2021         u8 iManufacturer;
2022         u8 iProduct;
2023
2024         /*
2025          * these variables may have been set in
2026          * usb_composite_overwrite_options()
2027          */
2028         idVendor = new->idVendor;
2029         idProduct = new->idProduct;
2030         bcdDevice = new->bcdDevice;
2031         iSerialNumber = new->iSerialNumber;
2032         iManufacturer = new->iManufacturer;
2033         iProduct = new->iProduct;
2034
2035         *new = *old;
2036         if (idVendor)
2037                 new->idVendor = idVendor;
2038         if (idProduct)
2039                 new->idProduct = idProduct;
2040         if (bcdDevice)
2041                 new->bcdDevice = bcdDevice;
2042         else
2043                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2044         if (iSerialNumber)
2045                 new->iSerialNumber = iSerialNumber;
2046         if (iManufacturer)
2047                 new->iManufacturer = iManufacturer;
2048         if (iProduct)
2049                 new->iProduct = iProduct;
2050 }
2051
2052 int composite_dev_prepare(struct usb_composite_driver *composite,
2053                 struct usb_composite_dev *cdev)
2054 {
2055         struct usb_gadget *gadget = cdev->gadget;
2056         int ret = -ENOMEM;
2057
2058         /* preallocate control response and buffer */
2059         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2060         if (!cdev->req)
2061                 return -ENOMEM;
2062
2063         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2064         if (!cdev->req->buf)
2065                 goto fail;
2066
2067         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2068         if (ret)
2069                 goto fail_dev;
2070
2071         cdev->req->complete = composite_setup_complete;
2072         cdev->req->context = cdev;
2073         gadget->ep0->driver_data = cdev;
2074
2075         cdev->driver = composite;
2076
2077         /*
2078          * As per USB compliance update, a device that is actively drawing
2079          * more than 100mA from USB must report itself as bus-powered in
2080          * the GetStatus(DEVICE) call.
2081          */
2082         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2083                 usb_gadget_set_selfpowered(gadget);
2084
2085         /* interface and string IDs start at zero via kzalloc.
2086          * we force endpoints to start unassigned; few controller
2087          * drivers will zero ep->driver_data.
2088          */
2089         usb_ep_autoconfig_reset(gadget);
2090         return 0;
2091 fail_dev:
2092         kfree(cdev->req->buf);
2093 fail:
2094         usb_ep_free_request(gadget->ep0, cdev->req);
2095         cdev->req = NULL;
2096         return ret;
2097 }
2098
2099 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2100                                   struct usb_ep *ep0)
2101 {
2102         int ret = 0;
2103
2104         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2105         if (!cdev->os_desc_req) {
2106                 ret = PTR_ERR(cdev->os_desc_req);
2107                 goto end;
2108         }
2109
2110         /* OS feature descriptor length <= 4kB */
2111         cdev->os_desc_req->buf = kmalloc(4096, GFP_KERNEL);
2112         if (!cdev->os_desc_req->buf) {
2113                 ret = PTR_ERR(cdev->os_desc_req->buf);
2114                 kfree(cdev->os_desc_req);
2115                 goto end;
2116         }
2117         cdev->os_desc_req->context = cdev;
2118         cdev->os_desc_req->complete = composite_setup_complete;
2119 end:
2120         return ret;
2121 }
2122
2123 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2124 {
2125         struct usb_gadget_string_container *uc, *tmp;
2126
2127         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2128                 list_del(&uc->list);
2129                 kfree(uc);
2130         }
2131         if (cdev->os_desc_req) {
2132                 if (cdev->os_desc_pending)
2133                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2134
2135                 kfree(cdev->os_desc_req->buf);
2136                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2137         }
2138         if (cdev->req) {
2139                 if (cdev->setup_pending)
2140                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2141
2142                 kfree(cdev->req->buf);
2143                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2144         }
2145         cdev->next_string_id = 0;
2146         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2147 }
2148
2149 static int composite_bind(struct usb_gadget *gadget,
2150                 struct usb_gadget_driver *gdriver)
2151 {
2152         struct usb_composite_dev        *cdev;
2153         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2154         int                             status = -ENOMEM;
2155
2156         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2157         if (!cdev)
2158                 return status;
2159
2160         spin_lock_init(&cdev->lock);
2161         cdev->gadget = gadget;
2162         set_gadget_data(gadget, cdev);
2163         INIT_LIST_HEAD(&cdev->configs);
2164         INIT_LIST_HEAD(&cdev->gstrings);
2165
2166         status = composite_dev_prepare(composite, cdev);
2167         if (status)
2168                 goto fail;
2169
2170         /* composite gadget needs to assign strings for whole device (like
2171          * serial number), register function drivers, potentially update
2172          * power state and consumption, etc
2173          */
2174         status = composite->bind(cdev);
2175         if (status < 0)
2176                 goto fail;
2177
2178         if (cdev->use_os_string) {
2179                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2180                 if (status)
2181                         goto fail;
2182         }
2183
2184         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2185
2186         /* has userspace failed to provide a serial number? */
2187         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2188                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2189
2190         INFO(cdev, "%s ready\n", composite->name);
2191         return 0;
2192
2193 fail:
2194         __composite_unbind(gadget, false);
2195         return status;
2196 }
2197
2198 /*-------------------------------------------------------------------------*/
2199
2200 void composite_suspend(struct usb_gadget *gadget)
2201 {
2202         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2203         struct usb_function             *f;
2204
2205         /* REVISIT:  should we have config level
2206          * suspend/resume callbacks?
2207          */
2208         DBG(cdev, "suspend\n");
2209         if (cdev->config) {
2210                 list_for_each_entry(f, &cdev->config->functions, list) {
2211                         if (f->suspend)
2212                                 f->suspend(f);
2213                 }
2214         }
2215         if (cdev->driver->suspend)
2216                 cdev->driver->suspend(cdev);
2217
2218         cdev->suspended = 1;
2219
2220         usb_gadget_vbus_draw(gadget, 2);
2221 }
2222
2223 void composite_resume(struct usb_gadget *gadget)
2224 {
2225         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2226         struct usb_function             *f;
2227         u16                             maxpower;
2228
2229         /* REVISIT:  should we have config level
2230          * suspend/resume callbacks?
2231          */
2232         DBG(cdev, "resume\n");
2233         if (cdev->driver->resume)
2234                 cdev->driver->resume(cdev);
2235         if (cdev->config) {
2236                 list_for_each_entry(f, &cdev->config->functions, list) {
2237                         if (f->resume)
2238                                 f->resume(f);
2239                 }
2240
2241                 maxpower = cdev->config->MaxPower;
2242
2243                 usb_gadget_vbus_draw(gadget, maxpower ?
2244                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
2245         }
2246
2247         cdev->suspended = 0;
2248 }
2249
2250 /*-------------------------------------------------------------------------*/
2251
2252 static const struct usb_gadget_driver composite_driver_template = {
2253         .bind           = composite_bind,
2254         .unbind         = composite_unbind,
2255
2256         .setup          = composite_setup,
2257         .reset          = composite_disconnect,
2258         .disconnect     = composite_disconnect,
2259
2260         .suspend        = composite_suspend,
2261         .resume         = composite_resume,
2262
2263         .driver = {
2264                 .owner          = THIS_MODULE,
2265         },
2266 };
2267
2268 /**
2269  * usb_composite_probe() - register a composite driver
2270  * @driver: the driver to register
2271  *
2272  * Context: single threaded during gadget setup
2273  *
2274  * This function is used to register drivers using the composite driver
2275  * framework.  The return value is zero, or a negative errno value.
2276  * Those values normally come from the driver's @bind method, which does
2277  * all the work of setting up the driver to match the hardware.
2278  *
2279  * On successful return, the gadget is ready to respond to requests from
2280  * the host, unless one of its components invokes usb_gadget_disconnect()
2281  * while it was binding.  That would usually be done in order to wait for
2282  * some userspace participation.
2283  */
2284 int usb_composite_probe(struct usb_composite_driver *driver)
2285 {
2286         struct usb_gadget_driver *gadget_driver;
2287
2288         if (!driver || !driver->dev || !driver->bind)
2289                 return -EINVAL;
2290
2291         if (!driver->name)
2292                 driver->name = "composite";
2293
2294         driver->gadget_driver = composite_driver_template;
2295         gadget_driver = &driver->gadget_driver;
2296
2297         gadget_driver->function =  (char *) driver->name;
2298         gadget_driver->driver.name = driver->name;
2299         gadget_driver->max_speed = driver->max_speed;
2300
2301         return usb_gadget_probe_driver(gadget_driver);
2302 }
2303 EXPORT_SYMBOL_GPL(usb_composite_probe);
2304
2305 /**
2306  * usb_composite_unregister() - unregister a composite driver
2307  * @driver: the driver to unregister
2308  *
2309  * This function is used to unregister drivers using the composite
2310  * driver framework.
2311  */
2312 void usb_composite_unregister(struct usb_composite_driver *driver)
2313 {
2314         usb_gadget_unregister_driver(&driver->gadget_driver);
2315 }
2316 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2317
2318 /**
2319  * usb_composite_setup_continue() - Continue with the control transfer
2320  * @cdev: the composite device who's control transfer was kept waiting
2321  *
2322  * This function must be called by the USB function driver to continue
2323  * with the control transfer's data/status stage in case it had requested to
2324  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2325  * can request the composite framework to delay the setup request's data/status
2326  * stages by returning USB_GADGET_DELAYED_STATUS.
2327  */
2328 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2329 {
2330         int                     value;
2331         struct usb_request      *req = cdev->req;
2332         unsigned long           flags;
2333
2334         DBG(cdev, "%s\n", __func__);
2335         spin_lock_irqsave(&cdev->lock, flags);
2336
2337         if (cdev->delayed_status == 0) {
2338                 WARN(cdev, "%s: Unexpected call\n", __func__);
2339
2340         } else if (--cdev->delayed_status == 0) {
2341                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2342                 req->length = 0;
2343                 req->context = cdev;
2344                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2345                 if (value < 0) {
2346                         DBG(cdev, "ep_queue --> %d\n", value);
2347                         req->status = 0;
2348                         composite_setup_complete(cdev->gadget->ep0, req);
2349                 }
2350         }
2351
2352         spin_unlock_irqrestore(&cdev->lock, flags);
2353 }
2354 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2355
2356 static char *composite_default_mfr(struct usb_gadget *gadget)
2357 {
2358         char *mfr;
2359         int len;
2360
2361         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
2362                         init_utsname()->release, gadget->name);
2363         len++;
2364         mfr = kmalloc(len, GFP_KERNEL);
2365         if (!mfr)
2366                 return NULL;
2367         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
2368                         init_utsname()->release, gadget->name);
2369         return mfr;
2370 }
2371
2372 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2373                 struct usb_composite_overwrite *covr)
2374 {
2375         struct usb_device_descriptor    *desc = &cdev->desc;
2376         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2377         struct usb_string               *dev_str = gstr->strings;
2378
2379         if (covr->idVendor)
2380                 desc->idVendor = cpu_to_le16(covr->idVendor);
2381
2382         if (covr->idProduct)
2383                 desc->idProduct = cpu_to_le16(covr->idProduct);
2384
2385         if (covr->bcdDevice)
2386                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2387
2388         if (covr->serial_number) {
2389                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2390                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2391         }
2392         if (covr->manufacturer) {
2393                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2394                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2395
2396         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2397                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2398                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2399                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2400         }
2401
2402         if (covr->product) {
2403                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2404                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2405         }
2406 }
2407 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2408
2409 MODULE_LICENSE("GPL");
2410 MODULE_AUTHOR("David Brownell");