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 <asm/unaligned.h>
  23
  24 #include "u_os_desc.h"
  25
  26 /**
  27  * struct usb_os_string - represents OS String to be reported by a gadget
  28  * @bLength: total length of the entire descritor, always 0x12
  29  * @bDescriptorType: USB_DT_STRING
  30  * @qwSignature: the OS String proper
  31  * @bMS_VendorCode: code used by the host for subsequent requests
  32  * @bPad: not used, must be zero
  33  */
  34 struct usb_os_string {
  35         __u8    bLength;
  36         __u8    bDescriptorType;
  37         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  38         __u8    bMS_VendorCode;
  39         __u8    bPad;
  40 } __packed;
  41
  42 /*
  43  * The code in this file is utility code, used to build a gadget driver
  44  * from one or more "function" drivers, one or more "configuration"
  45  * objects, and a "usb_composite_driver" by gluing them together along
  46  * with the relevant device-wide data.
  47  */
  48
  49 static struct usb_gadget_strings **get_containers_gs(
  50                 struct usb_gadget_string_container *uc)
  51 {
  52         return (struct usb_gadget_strings **)uc->stash;
  53 }
  54
  55 /**
  56  * next_ep_desc() - advance to the next EP descriptor
  57  * @t: currect pointer within descriptor array
  58  *
  59  * Return: next EP descriptor or NULL
  60  *
  61  * Iterate over @t until either EP descriptor found or
  62  * NULL (that indicates end of list) encountered
  63  */
  64 static struct usb_descriptor_header**
  65 next_ep_desc(struct usb_descriptor_header **t)
  66 {
  67         for (; *t; t++) {
  68                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
  69                         return t;
  70         }
  71         return NULL;
  72 }
  73
  74 /*
  75  * for_each_ep_desc()- iterate over endpoint descriptors in the
  76  *              descriptors list
  77  * @start:      pointer within descriptor array.
  78  * @ep_desc:    endpoint descriptor to use as the loop cursor
  79  */
  80 #define for_each_ep_desc(start, ep_desc) \
  81         for (ep_desc = next_ep_desc(start); \
  82               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
  83
  84 /**
  85  * config_ep_by_speed() - configures the given endpoint
  86  * according to gadget speed.
  87  * @g: pointer to the gadget
  88  * @f: usb function
  89  * @_ep: the endpoint to configure
  90  *
  91  * Return: error code, 0 on success
  92  *
  93  * This function chooses the right descriptors for a given
  94  * endpoint according to gadget speed and saves it in the
  95  * endpoint desc field. If the endpoint already has a descriptor
  96  * assigned to it - overwrites it with currently corresponding
  97  * descriptor. The endpoint maxpacket field is updated according
  98  * to the chosen descriptor.
  99  * Note: the supplied function should hold all the descriptors
 100  * for supported speeds
 101  */
 102 int config_ep_by_speed(struct usb_gadget *g,
 103                         struct usb_function *f,
 104                         struct usb_ep *_ep)
 105 {
 106         struct usb_composite_dev        *cdev = get_gadget_data(g);
 107         struct usb_endpoint_descriptor *chosen_desc = NULL;
 108         struct usb_descriptor_header **speed_desc = NULL;
 109
 110         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 111         int want_comp_desc = 0;
 112
 113         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 114
 115         if (!g || !f || !_ep)
 116                 return -EIO;
 117
 118         /* select desired speed */
 119         switch (g->speed) {
 120         case USB_SPEED_SUPER:
 121                 if (gadget_is_superspeed(g)) {
 122                         speed_desc = f->ss_descriptors;
 123                         want_comp_desc = 1;
 124                         break;
 125                 }
 126                 /* else: Fall trough */
 127         case USB_SPEED_HIGH:
 128                 if (gadget_is_dualspeed(g)) {
 129                         speed_desc = f->hs_descriptors;
 130                         break;
 131                 }
 132                 /* else: fall through */
 133         default:
 134                 speed_desc = f->fs_descriptors;
 135         }
 136         /* find descriptors */
 137         for_each_ep_desc(speed_desc, d_spd) {
 138                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 139                 if (chosen_desc->bEndpointAddress == _ep->address)
 140                         goto ep_found;
 141         }
 142         return -EIO;
 143
 144 ep_found:
 145         /* commit results */
 146         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 147         _ep->desc = chosen_desc;
 148         _ep->comp_desc = NULL;
 149         _ep->maxburst = 0;
 150         _ep->mult = 0;
 151         if (!want_comp_desc)
 152                 return 0;
 153
 154         /*
 155          * Companion descriptor should follow EP descriptor
 156          * USB 3.0 spec, #9.6.7
 157          */
 158         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 159         if (!comp_desc ||
 160             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 161                 return -EIO;
 162         _ep->comp_desc = comp_desc;
 163         if (g->speed == USB_SPEED_SUPER) {
 164                 switch (usb_endpoint_type(_ep->desc)) {
 165                 case USB_ENDPOINT_XFER_ISOC:
 166                         /* mult: bits 1:0 of bmAttributes */
 167                         _ep->mult = comp_desc->bmAttributes & 0x3;
 168                 case USB_ENDPOINT_XFER_BULK:
 169                 case USB_ENDPOINT_XFER_INT:
 170                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 171                         break;
 172                 default:
 173                         if (comp_desc->bMaxBurst != 0)
 174                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 175                         _ep->maxburst = 1;
 176                         break;
 177                 }
 178         }
 179         return 0;
 180 }
 181 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 182
 183 /**
 184  * usb_add_function() - add a function to a configuration
 185  * @config: the configuration
 186  * @function: the function being added
 187  * Context: single threaded during gadget setup
 188  *
 189  * After initialization, each configuration must have one or more
 190  * functions added to it.  Adding a function involves calling its @bind()
 191  * method to allocate resources such as interface and string identifiers
 192  * and endpoints.
 193  *
 194  * This function returns the value of the function's bind(), which is
 195  * zero for success else a negative errno value.
 196  */
 197 int usb_add_function(struct usb_configuration *config,
 198                 struct usb_function *function)
 199 {
 200         int     value = -EINVAL;
 201
 202         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 203                         function->name, function,
 204                         config->label, config);
 205
 206         if (!function->set_alt || !function->disable)
 207                 goto done;
 208
 209         function->config = config;
 210         list_add_tail(&function->list, &config->functions);
 211
 212         /* REVISIT *require* function->bind? */
 213         if (function->bind) {
 214                 value = function->bind(config, function);
 215                 if (value < 0) {
 216                         list_del(&function->list);
 217                         function->config = NULL;
 218                 }
 219         } else
 220                 value = 0;
 221
 222         /* We allow configurations that don't work at both speeds.
 223          * If we run into a lowspeed Linux system, treat it the same
 224          * as full speed ... it's the function drivers that will need
 225          * to avoid bulk and ISO transfers.
 226          */
 227         if (!config->fullspeed && function->fs_descriptors)
 228                 config->fullspeed = true;
 229         if (!config->highspeed && function->hs_descriptors)
 230                 config->highspeed = true;
 231         if (!config->superspeed && function->ss_descriptors)
 232                 config->superspeed = true;
 233
 234 done:
 235         if (value)
 236                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 237                                 function->name, function, value);
 238         return value;
 239 }
 240 EXPORT_SYMBOL_GPL(usb_add_function);
 241
 242 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 243 {
 244         if (f->disable)
 245                 f->disable(f);
 246
 247         bitmap_zero(f->endpoints, 32);
 248         list_del(&f->list);
 249         if (f->unbind)
 250                 f->unbind(c, f);
 251 }
 252 EXPORT_SYMBOL_GPL(usb_remove_function);
 253
 254 /**
 255  * usb_function_deactivate - prevent function and gadget enumeration
 256  * @function: the function that isn't yet ready to respond
 257  *
 258  * Blocks response of the gadget driver to host enumeration by
 259  * preventing the data line pullup from being activated.  This is
 260  * normally called during @bind() processing to change from the
 261  * initial "ready to respond" state, or when a required resource
 262  * becomes available.
 263  *
 264  * For example, drivers that serve as a passthrough to a userspace
 265  * daemon can block enumeration unless that daemon (such as an OBEX,
 266  * MTP, or print server) is ready to handle host requests.
 267  *
 268  * Not all systems support software control of their USB peripheral
 269  * data pullups.
 270  *
 271  * Returns zero on success, else negative errno.
 272  */
 273 int usb_function_deactivate(struct usb_function *function)
 274 {
 275         struct usb_composite_dev        *cdev = function->config->cdev;
 276         unsigned long                   flags;
 277         int                             status = 0;
 278
 279         spin_lock_irqsave(&cdev->lock, flags);
 280
 281         if (cdev->deactivations == 0)
 282                 status = usb_gadget_disconnect(cdev->gadget);
 283         if (status == 0)
 284                 cdev->deactivations++;
 285
 286         spin_unlock_irqrestore(&cdev->lock, flags);
 287         return status;
 288 }
 289 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 290
 291 /**
 292  * usb_function_activate - allow function and gadget enumeration
 293  * @function: function on which usb_function_activate() was called
 294  *
 295  * Reverses effect of usb_function_deactivate().  If no more functions
 296  * are delaying their activation, the gadget driver will respond to
 297  * host enumeration procedures.
 298  *
 299  * Returns zero on success, else negative errno.
 300  */
 301 int usb_function_activate(struct usb_function *function)
 302 {
 303         struct usb_composite_dev        *cdev = function->config->cdev;
 304         unsigned long                   flags;
 305         int                             status = 0;
 306
 307         spin_lock_irqsave(&cdev->lock, flags);
 308
 309         if (WARN_ON(cdev->deactivations == 0))
 310                 status = -EINVAL;
 311         else {
 312                 cdev->deactivations--;
 313                 if (cdev->deactivations == 0)
 314                         status = usb_gadget_connect(cdev->gadget);
 315         }
 316
 317         spin_unlock_irqrestore(&cdev->lock, flags);
 318         return status;
 319 }
 320 EXPORT_SYMBOL_GPL(usb_function_activate);
 321
 322 /**
 323  * usb_interface_id() - allocate an unused interface ID
 324  * @config: configuration associated with the interface
 325  * @function: function handling the interface
 326  * Context: single threaded during gadget setup
 327  *
 328  * usb_interface_id() is called from usb_function.bind() callbacks to
 329  * allocate new interface IDs.  The function driver will then store that
 330  * ID in interface, association, CDC union, and other descriptors.  It
 331  * will also handle any control requests targeted at that interface,
 332  * particularly changing its altsetting via set_alt().  There may
 333  * also be class-specific or vendor-specific requests to handle.
 334  *
 335  * All interface identifier should be allocated using this routine, to
 336  * ensure that for example different functions don't wrongly assign
 337  * different meanings to the same identifier.  Note that since interface
 338  * identifiers are configuration-specific, functions used in more than
 339  * one configuration (or more than once in a given configuration) need
 340  * multiple versions of the relevant descriptors.
 341  *
 342  * Returns the interface ID which was allocated; or -ENODEV if no
 343  * more interface IDs can be allocated.
 344  */
 345 int usb_interface_id(struct usb_configuration *config,
 346                 struct usb_function *function)
 347 {
 348         unsigned id = config->next_interface_id;
 349
 350         if (id < MAX_CONFIG_INTERFACES) {
 351                 config->interface[id] = function;
 352                 config->next_interface_id = id + 1;
 353                 return id;
 354         }
 355         return -ENODEV;
 356 }
 357 EXPORT_SYMBOL_GPL(usb_interface_id);
 358
 359 static u8 encode_bMaxPower(enum usb_device_speed speed,
 360                 struct usb_configuration *c)
 361 {
 362         unsigned val;
 363
 364         if (c->MaxPower)
 365                 val = c->MaxPower;
 366         else
 367                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 368         if (!val)
 369                 return 0;
 370         switch (speed) {
 371         case USB_SPEED_SUPER:
 372                 return DIV_ROUND_UP(val, 8);
 373         default:
 374                 return DIV_ROUND_UP(val, 2);
 375         }
 376 }
 377
 378 static int config_buf(struct usb_configuration *config,
 379                 enum usb_device_speed speed, void *buf, u8 type)
 380 {
 381         struct usb_config_descriptor    *c = buf;
 382         void                            *next = buf + USB_DT_CONFIG_SIZE;
 383         int                             len;
 384         struct usb_function             *f;
 385         int                             status;
 386
 387         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 388         /* write the config descriptor */
 389         c = buf;
 390         c->bLength = USB_DT_CONFIG_SIZE;
 391         c->bDescriptorType = type;
 392         /* wTotalLength is written later */
 393         c->bNumInterfaces = config->next_interface_id;
 394         c->bConfigurationValue = config->bConfigurationValue;
 395         c->iConfiguration = config->iConfiguration;
 396         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 397         c->bMaxPower = encode_bMaxPower(speed, config);
 398
 399         /* There may be e.g. OTG descriptors */
 400         if (config->descriptors) {
 401                 status = usb_descriptor_fillbuf(next, len,
 402                                 config->descriptors);
 403                 if (status < 0)
 404                         return status;
 405                 len -= status;
 406                 next += status;
 407         }
 408
 409         /* add each function's descriptors */
 410         list_for_each_entry(f, &config->functions, list) {
 411                 struct usb_descriptor_header **descriptors;
 412
 413                 switch (speed) {
 414                 case USB_SPEED_SUPER:
 415                         descriptors = f->ss_descriptors;
 416                         break;
 417                 case USB_SPEED_HIGH:
 418                         descriptors = f->hs_descriptors;
 419                         break;
 420                 default:
 421                         descriptors = f->fs_descriptors;
 422                 }
 423
 424                 if (!descriptors)
 425                         continue;
 426                 status = usb_descriptor_fillbuf(next, len,
 427                         (const struct usb_descriptor_header **) descriptors);
 428                 if (status < 0)
 429                         return status;
 430                 len -= status;
 431                 next += status;
 432         }
 433
 434         len = next - buf;
 435         c->wTotalLength = cpu_to_le16(len);
 436         return len;
 437 }
 438
 439 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 440 {
 441         struct usb_gadget               *gadget = cdev->gadget;
 442         struct usb_configuration        *c;
 443         struct list_head                *pos;
 444         u8                              type = w_value >> 8;
 445         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 446
 447         if (gadget->speed == USB_SPEED_SUPER)
 448                 speed = gadget->speed;
 449         else if (gadget_is_dualspeed(gadget)) {
 450                 int     hs = 0;
 451                 if (gadget->speed == USB_SPEED_HIGH)
 452                         hs = 1;
 453                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 454                         hs = !hs;
 455                 if (hs)
 456                         speed = USB_SPEED_HIGH;
 457
 458         }
 459
 460         /* This is a lookup by config *INDEX* */
 461         w_value &= 0xff;
 462
 463         pos = &cdev->configs;
 464         c = cdev->os_desc_config;
 465         if (c)
 466                 goto check_config;
 467
 468         while ((pos = pos->next) !=  &cdev->configs) {
 469                 c = list_entry(pos, typeof(*c), list);
 470
 471                 /* skip OS Descriptors config which is handled separately */
 472                 if (c == cdev->os_desc_config)
 473                         continue;
 474
 475 check_config:
 476                 /* ignore configs that won't work at this speed */
 477                 switch (speed) {
 478                 case USB_SPEED_SUPER:
 479                         if (!c->superspeed)
 480                                 continue;
 481                         break;
 482                 case USB_SPEED_HIGH:
 483                         if (!c->highspeed)
 484                                 continue;
 485                         break;
 486                 default:
 487                         if (!c->fullspeed)
 488                                 continue;
 489                 }
 490
 491                 if (w_value == 0)
 492                         return config_buf(c, speed, cdev->req->buf, type);
 493                 w_value--;
 494         }
 495         return -EINVAL;
 496 }
 497
 498 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 499 {
 500         struct usb_gadget               *gadget = cdev->gadget;
 501         struct usb_configuration        *c;
 502         unsigned                        count = 0;
 503         int                             hs = 0;
 504         int                             ss = 0;
 505
 506         if (gadget_is_dualspeed(gadget)) {
 507                 if (gadget->speed == USB_SPEED_HIGH)
 508                         hs = 1;
 509                 if (gadget->speed == USB_SPEED_SUPER)
 510                         ss = 1;
 511                 if (type == USB_DT_DEVICE_QUALIFIER)
 512                         hs = !hs;
 513         }
 514         list_for_each_entry(c, &cdev->configs, list) {
 515                 /* ignore configs that won't work at this speed */
 516                 if (ss) {
 517                         if (!c->superspeed)
 518                                 continue;
 519                 } else if (hs) {
 520                         if (!c->highspeed)
 521                                 continue;
 522                 } else {
 523                         if (!c->fullspeed)
 524                                 continue;
 525                 }
 526                 count++;
 527         }
 528         return count;
 529 }
 530
 531 /**
 532  * bos_desc() - prepares the BOS descriptor.
 533  * @cdev: pointer to usb_composite device to generate the bos
 534  *      descriptor for
 535  *
 536  * This function generates the BOS (Binary Device Object)
 537  * descriptor and its device capabilities descriptors. The BOS
 538  * descriptor should be supported by a SuperSpeed device.
 539  */
 540 static int bos_desc(struct usb_composite_dev *cdev)
 541 {
 542         struct usb_ext_cap_descriptor   *usb_ext;
 543         struct usb_ss_cap_descriptor    *ss_cap;
 544         struct usb_dcd_config_params    dcd_config_params;
 545         struct usb_bos_descriptor       *bos = cdev->req->buf;
 546
 547         bos->bLength = USB_DT_BOS_SIZE;
 548         bos->bDescriptorType = USB_DT_BOS;
 549
 550         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 551         bos->bNumDeviceCaps = 0;
 552
 553         /*
 554          * A SuperSpeed device shall include the USB2.0 extension descriptor
 555          * and shall support LPM when operating in USB2.0 HS mode.
 556          */
 557         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 558         bos->bNumDeviceCaps++;
 559         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 560         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 561         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 562         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 563         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | USB_BESL_SUPPORT);
 564
 565         /*
 566          * The Superspeed USB Capability descriptor shall be implemented by all
 567          * SuperSpeed devices.
 568          */
 569         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 570         bos->bNumDeviceCaps++;
 571         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 572         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 573         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 574         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 575         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 576         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 577                                 USB_FULL_SPEED_OPERATION |
 578                                 USB_HIGH_SPEED_OPERATION |
 579                                 USB_5GBPS_OPERATION);
 580         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 581
 582         /* Get Controller configuration */
 583         if (cdev->gadget->ops->get_config_params)
 584                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 585         else {
 586                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 587                 dcd_config_params.bU2DevExitLat =
 588                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 589         }
 590         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 591         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 592
 593         return le16_to_cpu(bos->wTotalLength);
 594 }
 595
 596 static void device_qual(struct usb_composite_dev *cdev)
 597 {
 598         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 599
 600         qual->bLength = sizeof(*qual);
 601         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 602         /* POLICY: same bcdUSB and device type info at both speeds */
 603         qual->bcdUSB = cdev->desc.bcdUSB;
 604         qual->bDeviceClass = cdev->desc.bDeviceClass;
 605         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 606         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 607         /* ASSUME same EP0 fifo size at both speeds */
 608         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 609         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 610         qual->bRESERVED = 0;
 611 }
 612
 613 /*-------------------------------------------------------------------------*/
 614
 615 static void reset_config(struct usb_composite_dev *cdev)
 616 {
 617         struct usb_function             *f;
 618
 619         DBG(cdev, "reset config\n");
 620
 621         list_for_each_entry(f, &cdev->config->functions, list) {
 622                 if (f->disable)
 623                         f->disable(f);
 624
 625                 bitmap_zero(f->endpoints, 32);
 626         }
 627         cdev->config = NULL;
 628         cdev->delayed_status = 0;
 629 }
 630
 631 static int set_config(struct usb_composite_dev *cdev,
 632                 const struct usb_ctrlrequest *ctrl, unsigned number)
 633 {
 634         struct usb_gadget       *gadget = cdev->gadget;
 635         struct usb_configuration *c = NULL;
 636         int                     result = -EINVAL;
 637         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 638         int                     tmp;
 639
 640         if (number) {
 641                 list_for_each_entry(c, &cdev->configs, list) {
 642                         if (c->bConfigurationValue == number) {
 643                                 /*
 644                                  * We disable the FDs of the previous
 645                                  * configuration only if the new configuration
 646                                  * is a valid one
 647                                  */
 648                                 if (cdev->config)
 649                                         reset_config(cdev);
 650                                 result = 0;
 651                                 break;
 652                         }
 653                 }
 654                 if (result < 0)
 655                         goto done;
 656         } else { /* Zero configuration value - need to reset the config */
 657                 if (cdev->config)
 658                         reset_config(cdev);
 659                 result = 0;
 660         }
 661
 662         INFO(cdev, "%s config #%d: %s\n",
 663              usb_speed_string(gadget->speed),
 664              number, c ? c->label : "unconfigured");
 665
 666         if (!c)
 667                 goto done;
 668
 669         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 670         cdev->config = c;
 671
 672         /* Initialize all interfaces by setting them to altsetting zero. */
 673         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 674                 struct usb_function     *f = c->interface[tmp];
 675                 struct usb_descriptor_header **descriptors;
 676
 677                 if (!f)
 678                         break;
 679
 680                 /*
 681                  * Record which endpoints are used by the function. This is used
 682                  * to dispatch control requests targeted at that endpoint to the
 683                  * function's setup callback instead of the current
 684                  * configuration's setup callback.
 685                  */
 686                 switch (gadget->speed) {
 687                 case USB_SPEED_SUPER:
 688                         descriptors = f->ss_descriptors;
 689                         break;
 690                 case USB_SPEED_HIGH:
 691                         descriptors = f->hs_descriptors;
 692                         break;
 693                 default:
 694                         descriptors = f->fs_descriptors;
 695                 }
 696
 697                 for (; *descriptors; ++descriptors) {
 698                         struct usb_endpoint_descriptor *ep;
 699                         int addr;
 700
 701                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 702                                 continue;
 703
 704                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 705                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 706                              |  (ep->bEndpointAddress & 0x0f);
 707                         set_bit(addr, f->endpoints);
 708                 }
 709
 710                 result = f->set_alt(f, tmp, 0);
 711                 if (result < 0) {
 712                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 713                                         tmp, f->name, f, result);
 714
 715                         reset_config(cdev);
 716                         goto done;
 717                 }
 718
 719                 if (result == USB_GADGET_DELAYED_STATUS) {
 720                         DBG(cdev,
 721                          "%s: interface %d (%s) requested delayed status\n",
 722                                         __func__, tmp, f->name);
 723                         cdev->delayed_status++;
 724                         DBG(cdev, "delayed_status count %d\n",
 725                                         cdev->delayed_status);
 726                 }
 727         }
 728
 729         /* when we return, be sure our power usage is valid */
 730         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 731 done:
 732         usb_gadget_vbus_draw(gadget, power);
 733         if (result >= 0 && cdev->delayed_status)
 734                 result = USB_GADGET_DELAYED_STATUS;
 735         return result;
 736 }
 737
 738 int usb_add_config_only(struct usb_composite_dev *cdev,
 739                 struct usb_configuration *config)
 740 {
 741         struct usb_configuration *c;
 742
 743         if (!config->bConfigurationValue)
 744                 return -EINVAL;
 745
 746         /* Prevent duplicate configuration identifiers */
 747         list_for_each_entry(c, &cdev->configs, list) {
 748                 if (c->bConfigurationValue == config->bConfigurationValue)
 749                         return -EBUSY;
 750         }
 751
 752         config->cdev = cdev;
 753         list_add_tail(&config->list, &cdev->configs);
 754
 755         INIT_LIST_HEAD(&config->functions);
 756         config->next_interface_id = 0;
 757         memset(config->interface, 0, sizeof(config->interface));
 758
 759         return 0;
 760 }
 761 EXPORT_SYMBOL_GPL(usb_add_config_only);
 762
 763 /**
 764  * usb_add_config() - add a configuration to a device.
 765  * @cdev: wraps the USB gadget
 766  * @config: the configuration, with bConfigurationValue assigned
 767  * @bind: the configuration's bind function
 768  * Context: single threaded during gadget setup
 769  *
 770  * One of the main tasks of a composite @bind() routine is to
 771  * add each of the configurations it supports, using this routine.
 772  *
 773  * This function returns the value of the configuration's @bind(), which
 774  * is zero for success else a negative errno value.  Binding configurations
 775  * assigns global resources including string IDs, and per-configuration
 776  * resources such as interface IDs and endpoints.
 777  */
 778 int usb_add_config(struct usb_composite_dev *cdev,
 779                 struct usb_configuration *config,
 780                 int (*bind)(struct usb_configuration *))
 781 {
 782         int                             status = -EINVAL;
 783
 784         if (!bind)
 785                 goto done;
 786
 787         DBG(cdev, "adding config #%u '%s'/%p\n",
 788                         config->bConfigurationValue,
 789                         config->label, config);
 790
 791         status = usb_add_config_only(cdev, config);
 792         if (status)
 793                 goto done;
 794
 795         status = bind(config);
 796         if (status < 0) {
 797                 while (!list_empty(&config->functions)) {
 798                         struct usb_function             *f;
 799
 800                         f = list_first_entry(&config->functions,
 801                                         struct usb_function, list);
 802                         list_del(&f->list);
 803                         if (f->unbind) {
 804                                 DBG(cdev, "unbind function '%s'/%p\n",
 805                                         f->name, f);
 806                                 f->unbind(config, f);
 807                                 /* may free memory for "f" */
 808                         }
 809                 }
 810                 list_del(&config->list);
 811                 config->cdev = NULL;
 812         } else {
 813                 unsigned        i;
 814
 815                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 816                         config->bConfigurationValue, config,
 817                         config->superspeed ? " super" : "",
 818                         config->highspeed ? " high" : "",
 819                         config->fullspeed
 820                                 ? (gadget_is_dualspeed(cdev->gadget)
 821                                         ? " full"
 822                                         : " full/low")
 823                                 : "");
 824
 825                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 826                         struct usb_function     *f = config->interface[i];
 827
 828                         if (!f)
 829                                 continue;
 830                         DBG(cdev, "  interface %d = %s/%p\n",
 831                                 i, f->name, f);
 832                 }
 833         }
 834
 835         /* set_alt(), or next bind(), sets up
 836          * ep->driver_data as needed.
 837          */
 838         usb_ep_autoconfig_reset(cdev->gadget);
 839
 840 done:
 841         if (status)
 842                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 843                                 config->bConfigurationValue, status);
 844         return status;
 845 }
 846 EXPORT_SYMBOL_GPL(usb_add_config);
 847
 848 static void remove_config(struct usb_composite_dev *cdev,
 849                               struct usb_configuration *config)
 850 {
 851         while (!list_empty(&config->functions)) {
 852                 struct usb_function             *f;
 853
 854                 f = list_first_entry(&config->functions,
 855                                 struct usb_function, list);
 856                 list_del(&f->list);
 857                 if (f->unbind) {
 858                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 859                         f->unbind(config, f);
 860                         /* may free memory for "f" */
 861                 }
 862         }
 863         list_del(&config->list);
 864         if (config->unbind) {
 865                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 866                 config->unbind(config);
 867                         /* may free memory for "c" */
 868         }
 869 }
 870
 871 /**
 872  * usb_remove_config() - remove a configuration from a device.
 873  * @cdev: wraps the USB gadget
 874  * @config: the configuration
 875  *
 876  * Drivers must call usb_gadget_disconnect before calling this function
 877  * to disconnect the device from the host and make sure the host will not
 878  * try to enumerate the device while we are changing the config list.
 879  */
 880 void usb_remove_config(struct usb_composite_dev *cdev,
 881                       struct usb_configuration *config)
 882 {
 883         unsigned long flags;
 884
 885         spin_lock_irqsave(&cdev->lock, flags);
 886
 887         if (cdev->config == config)
 888                 reset_config(cdev);
 889
 890         spin_unlock_irqrestore(&cdev->lock, flags);
 891
 892         remove_config(cdev, config);
 893 }
 894
 895 /*-------------------------------------------------------------------------*/
 896
 897 /* We support strings in multiple languages ... string descriptor zero
 898  * says which languages are supported.  The typical case will be that
 899  * only one language (probably English) is used, with I18N handled on
 900  * the host side.
 901  */
 902
 903 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 904 {
 905         const struct usb_gadget_strings *s;
 906         __le16                          language;
 907         __le16                          *tmp;
 908
 909         while (*sp) {
 910                 s = *sp;
 911                 language = cpu_to_le16(s->language);
 912                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 913                         if (*tmp == language)
 914                                 goto repeat;
 915                 }
 916                 *tmp++ = language;
 917 repeat:
 918                 sp++;
 919         }
 920 }
 921
 922 static int lookup_string(
 923         struct usb_gadget_strings       **sp,
 924         void                            *buf,
 925         u16                             language,
 926         int                             id
 927 )
 928 {
 929         struct usb_gadget_strings       *s;
 930         int                             value;
 931
 932         while (*sp) {
 933                 s = *sp++;
 934                 if (s->language != language)
 935                         continue;
 936                 value = usb_gadget_get_string(s, id, buf);
 937                 if (value > 0)
 938                         return value;
 939         }
 940         return -EINVAL;
 941 }
 942
 943 static int get_string(struct usb_composite_dev *cdev,
 944                 void *buf, u16 language, int id)
 945 {
 946         struct usb_composite_driver     *composite = cdev->driver;
 947         struct usb_gadget_string_container *uc;
 948         struct usb_configuration        *c;
 949         struct usb_function             *f;
 950         int                             len;
 951
 952         /* Yes, not only is USB's I18N support probably more than most
 953          * folk will ever care about ... also, it's all supported here.
 954          * (Except for UTF8 support for Unicode's "Astral Planes".)
 955          */
 956
 957         /* 0 == report all available language codes */
 958         if (id == 0) {
 959                 struct usb_string_descriptor    *s = buf;
 960                 struct usb_gadget_strings       **sp;
 961
 962                 memset(s, 0, 256);
 963                 s->bDescriptorType = USB_DT_STRING;
 964
 965                 sp = composite->strings;
 966                 if (sp)
 967                         collect_langs(sp, s->wData);
 968
 969                 list_for_each_entry(c, &cdev->configs, list) {
 970                         sp = c->strings;
 971                         if (sp)
 972                                 collect_langs(sp, s->wData);
 973
 974                         list_for_each_entry(f, &c->functions, list) {
 975                                 sp = f->strings;
 976                                 if (sp)
 977                                         collect_langs(sp, s->wData);
 978                         }
 979                 }
 980                 list_for_each_entry(uc, &cdev->gstrings, list) {
 981                         struct usb_gadget_strings **sp;
 982
 983                         sp = get_containers_gs(uc);
 984                         collect_langs(sp, s->wData);
 985                 }
 986
 987                 for (len = 0; len <= 126 && s->wData[len]; len++)
 988                         continue;
 989                 if (!len)
 990                         return -EINVAL;
 991
 992                 s->bLength = 2 * (len + 1);
 993                 return s->bLength;
 994         }
 995
 996         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
 997                 struct usb_os_string *b = buf;
 998                 b->bLength = sizeof(*b);
 999                 b->bDescriptorType = USB_DT_STRING;
1000                 compiletime_assert(
1001                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1002                         "qwSignature size must be equal to qw_sign");
1003                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1004                 b->bMS_VendorCode = cdev->b_vendor_code;
1005                 b->bPad = 0;
1006                 return sizeof(*b);
1007         }
1008
1009         list_for_each_entry(uc, &cdev->gstrings, list) {
1010                 struct usb_gadget_strings **sp;
1011
1012                 sp = get_containers_gs(uc);
1013                 len = lookup_string(sp, buf, language, id);
1014                 if (len > 0)
1015                         return len;
1016         }
1017
1018         /* String IDs are device-scoped, so we look up each string
1019          * table we're told about.  These lookups are infrequent;
1020          * simpler-is-better here.
1021          */
1022         if (composite->strings) {
1023                 len = lookup_string(composite->strings, buf, language, id);
1024                 if (len > 0)
1025                         return len;
1026         }
1027         list_for_each_entry(c, &cdev->configs, list) {
1028                 if (c->strings) {
1029                         len = lookup_string(c->strings, buf, language, id);
1030                         if (len > 0)
1031                                 return len;
1032                 }
1033                 list_for_each_entry(f, &c->functions, list) {
1034                         if (!f->strings)
1035                                 continue;
1036                         len = lookup_string(f->strings, buf, language, id);
1037                         if (len > 0)
1038                                 return len;
1039                 }
1040         }
1041         return -EINVAL;
1042 }
1043
1044 /**
1045  * usb_string_id() - allocate an unused string ID
1046  * @cdev: the device whose string descriptor IDs are being allocated
1047  * Context: single threaded during gadget setup
1048  *
1049  * @usb_string_id() is called from bind() callbacks to allocate
1050  * string IDs.  Drivers for functions, configurations, or gadgets will
1051  * then store that ID in the appropriate descriptors and string table.
1052  *
1053  * All string identifier should be allocated using this,
1054  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1055  * that for example different functions don't wrongly assign different
1056  * meanings to the same identifier.
1057  */
1058 int usb_string_id(struct usb_composite_dev *cdev)
1059 {
1060         if (cdev->next_string_id < 254) {
1061                 /* string id 0 is reserved by USB spec for list of
1062                  * supported languages */
1063                 /* 255 reserved as well? -- mina86 */
1064                 cdev->next_string_id++;
1065                 return cdev->next_string_id;
1066         }
1067         return -ENODEV;
1068 }
1069 EXPORT_SYMBOL_GPL(usb_string_id);
1070
1071 /**
1072  * usb_string_ids() - allocate unused string IDs in batch
1073  * @cdev: the device whose string descriptor IDs are being allocated
1074  * @str: an array of usb_string objects to assign numbers to
1075  * Context: single threaded during gadget setup
1076  *
1077  * @usb_string_ids() is called from bind() callbacks to allocate
1078  * string IDs.  Drivers for functions, configurations, or gadgets will
1079  * then copy IDs from the string table to the appropriate descriptors
1080  * and string table for other languages.
1081  *
1082  * All string identifier should be allocated using this,
1083  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1084  * example different functions don't wrongly assign different meanings
1085  * to the same identifier.
1086  */
1087 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1088 {
1089         int next = cdev->next_string_id;
1090
1091         for (; str->s; ++str) {
1092                 if (unlikely(next >= 254))
1093                         return -ENODEV;
1094                 str->id = ++next;
1095         }
1096
1097         cdev->next_string_id = next;
1098
1099         return 0;
1100 }
1101 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1102
1103 static struct usb_gadget_string_container *copy_gadget_strings(
1104                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1105                 unsigned n_strings)
1106 {
1107         struct usb_gadget_string_container *uc;
1108         struct usb_gadget_strings **gs_array;
1109         struct usb_gadget_strings *gs;
1110         struct usb_string *s;
1111         unsigned mem;
1112         unsigned n_gs;
1113         unsigned n_s;
1114         void *stash;
1115
1116         mem = sizeof(*uc);
1117         mem += sizeof(void *) * (n_gstrings + 1);
1118         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1119         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1120         uc = kmalloc(mem, GFP_KERNEL);
1121         if (!uc)
1122                 return ERR_PTR(-ENOMEM);
1123         gs_array = get_containers_gs(uc);
1124         stash = uc->stash;
1125         stash += sizeof(void *) * (n_gstrings + 1);
1126         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1127                 struct usb_string *org_s;
1128
1129                 gs_array[n_gs] = stash;
1130                 gs = gs_array[n_gs];
1131                 stash += sizeof(struct usb_gadget_strings);
1132                 gs->language = sp[n_gs]->language;
1133                 gs->strings = stash;
1134                 org_s = sp[n_gs]->strings;
1135
1136                 for (n_s = 0; n_s < n_strings; n_s++) {
1137                         s = stash;
1138                         stash += sizeof(struct usb_string);
1139                         if (org_s->s)
1140                                 s->s = org_s->s;
1141                         else
1142                                 s->s = "";
1143                         org_s++;
1144                 }
1145                 s = stash;
1146                 s->s = NULL;
1147                 stash += sizeof(struct usb_string);
1148
1149         }
1150         gs_array[n_gs] = NULL;
1151         return uc;
1152 }
1153
1154 /**
1155  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1156  * @cdev: the device whose string descriptor IDs are being allocated
1157  * and attached.
1158  * @sp: an array of usb_gadget_strings to attach.
1159  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1160  *
1161  * This function will create a deep copy of usb_gadget_strings and usb_string
1162  * and attach it to the cdev. The actual string (usb_string.s) will not be
1163  * copied but only a referenced will be made. The struct usb_gadget_strings
1164  * array may contain multiple languages and should be NULL terminated.
1165  * The ->language pointer of each struct usb_gadget_strings has to contain the
1166  * same amount of entries.
1167  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1168  * usb_string entry of es-ES contains the translation of the first usb_string
1169  * entry of en-US. Therefore both entries become the same id assign.
1170  */
1171 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1172                 struct usb_gadget_strings **sp, unsigned n_strings)
1173 {
1174         struct usb_gadget_string_container *uc;
1175         struct usb_gadget_strings **n_gs;
1176         unsigned n_gstrings = 0;
1177         unsigned i;
1178         int ret;
1179
1180         for (i = 0; sp[i]; i++)
1181                 n_gstrings++;
1182
1183         if (!n_gstrings)
1184                 return ERR_PTR(-EINVAL);
1185
1186         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1187         if (IS_ERR(uc))
1188                 return ERR_CAST(uc);
1189
1190         n_gs = get_containers_gs(uc);
1191         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1192         if (ret)
1193                 goto err;
1194
1195         for (i = 1; i < n_gstrings; i++) {
1196                 struct usb_string *m_s;
1197                 struct usb_string *s;
1198                 unsigned n;
1199
1200                 m_s = n_gs[0]->strings;
1201                 s = n_gs[i]->strings;
1202                 for (n = 0; n < n_strings; n++) {
1203                         s->id = m_s->id;
1204                         s++;
1205                         m_s++;
1206                 }
1207         }
1208         list_add_tail(&uc->list, &cdev->gstrings);
1209         return n_gs[0]->strings;
1210 err:
1211         kfree(uc);
1212         return ERR_PTR(ret);
1213 }
1214 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1215
1216 /**
1217  * usb_string_ids_n() - allocate unused string IDs in batch
1218  * @c: the device whose string descriptor IDs are being allocated
1219  * @n: number of string IDs to allocate
1220  * Context: single threaded during gadget setup
1221  *
1222  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1223  * valid IDs.  At least provided that @n is non-zero because if it
1224  * is, returns last requested ID which is now very useful information.
1225  *
1226  * @usb_string_ids_n() is called from bind() callbacks to allocate
1227  * string IDs.  Drivers for functions, configurations, or gadgets will
1228  * then store that ID in the appropriate descriptors and string table.
1229  *
1230  * All string identifier should be allocated using this,
1231  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1232  * example different functions don't wrongly assign different meanings
1233  * to the same identifier.
1234  */
1235 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1236 {
1237         unsigned next = c->next_string_id;
1238         if (unlikely(n > 254 || (unsigned)next + n > 254))
1239                 return -ENODEV;
1240         c->next_string_id += n;
1241         return next + 1;
1242 }
1243 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1244
1245 /*-------------------------------------------------------------------------*/
1246
1247 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1248 {
1249         struct usb_composite_dev *cdev;
1250
1251         if (req->status || req->actual != req->length)
1252                 DBG((struct usb_composite_dev *) ep->driver_data,
1253                                 "setup complete --> %d, %d/%d\n",
1254                                 req->status, req->actual, req->length);
1255
1256         /*
1257          * REVIST The same ep0 requests are shared with function drivers
1258          * so they don't have to maintain the same ->complete() stubs.
1259          *
1260          * Because of that, we need to check for the validity of ->context
1261          * here, even though we know we've set it to something useful.
1262          */
1263         if (!req->context)
1264                 return;
1265
1266         cdev = req->context;
1267
1268         if (cdev->req == req)
1269                 cdev->setup_pending = false;
1270         else if (cdev->os_desc_req == req)
1271                 cdev->os_desc_pending = false;
1272         else
1273                 WARN(1, "unknown request %p\n", req);
1274 }
1275
1276 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1277                 struct usb_request *req, gfp_t gfp_flags)
1278 {
1279         int ret;
1280
1281         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1282         if (ret == 0) {
1283                 if (cdev->req == req)
1284                         cdev->setup_pending = true;
1285                 else if (cdev->os_desc_req == req)
1286                         cdev->os_desc_pending = true;
1287                 else
1288                         WARN(1, "unknown request %p\n", req);
1289         }
1290
1291         return ret;
1292 }
1293
1294 static int count_ext_compat(struct usb_configuration *c)
1295 {
1296         int i, res;
1297
1298         res = 0;
1299         for (i = 0; i < c->next_interface_id; ++i) {
1300                 struct usb_function *f;
1301                 int j;
1302
1303                 f = c->interface[i];
1304                 for (j = 0; j < f->os_desc_n; ++j) {
1305                         struct usb_os_desc *d;
1306
1307                         if (i != f->os_desc_table[j].if_id)
1308                                 continue;
1309                         d = f->os_desc_table[j].os_desc;
1310                         if (d && d->ext_compat_id)
1311                                 ++res;
1312                 }
1313         }
1314         BUG_ON(res > 255);
1315         return res;
1316 }
1317
1318 static void fill_ext_compat(struct usb_configuration *c, u8 *buf)
1319 {
1320         int i, count;
1321
1322         count = 16;
1323         for (i = 0; i < c->next_interface_id; ++i) {
1324                 struct usb_function *f;
1325                 int j;
1326
1327                 f = c->interface[i];
1328                 for (j = 0; j < f->os_desc_n; ++j) {
1329                         struct usb_os_desc *d;
1330
1331                         if (i != f->os_desc_table[j].if_id)
1332                                 continue;
1333                         d = f->os_desc_table[j].os_desc;
1334                         if (d && d->ext_compat_id) {
1335                                 *buf++ = i;
1336                                 *buf++ = 0x01;
1337                                 memcpy(buf, d->ext_compat_id, 16);
1338                                 buf += 22;
1339                         } else {
1340                                 ++buf;
1341                                 *buf = 0x01;
1342                                 buf += 23;
1343                         }
1344                         count += 24;
1345                         if (count >= 4096)
1346                                 return;
1347                 }
1348         }
1349 }
1350
1351 static int count_ext_prop(struct usb_configuration *c, int interface)
1352 {
1353         struct usb_function *f;
1354         int j;
1355
1356         f = c->interface[interface];
1357         for (j = 0; j < f->os_desc_n; ++j) {
1358                 struct usb_os_desc *d;
1359
1360                 if (interface != f->os_desc_table[j].if_id)
1361                         continue;
1362                 d = f->os_desc_table[j].os_desc;
1363                 if (d && d->ext_compat_id)
1364                         return d->ext_prop_count;
1365         }
1366         return 0;
1367 }
1368
1369 static int len_ext_prop(struct usb_configuration *c, int interface)
1370 {
1371         struct usb_function *f;
1372         struct usb_os_desc *d;
1373         int j, res;
1374
1375         res = 10; /* header length */
1376         f = c->interface[interface];
1377         for (j = 0; j < f->os_desc_n; ++j) {
1378                 if (interface != f->os_desc_table[j].if_id)
1379                         continue;
1380                 d = f->os_desc_table[j].os_desc;
1381                 if (d)
1382                         return min(res + d->ext_prop_len, 4096);
1383         }
1384         return res;
1385 }
1386
1387 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1388 {
1389         struct usb_function *f;
1390         struct usb_os_desc *d;
1391         struct usb_os_desc_ext_prop *ext_prop;
1392         int j, count, n, ret;
1393         u8 *start = buf;
1394
1395         f = c->interface[interface];
1396         for (j = 0; j < f->os_desc_n; ++j) {
1397                 if (interface != f->os_desc_table[j].if_id)
1398                         continue;
1399                 d = f->os_desc_table[j].os_desc;
1400                 if (d)
1401                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1402                                 /* 4kB minus header length */
1403                                 n = buf - start;
1404                                 if (n >= 4086)
1405                                         return 0;
1406
1407                                 count = ext_prop->data_len +
1408                                         ext_prop->name_len + 14;
1409                                 if (count > 4086 - n)
1410                                         return -EINVAL;
1411                                 usb_ext_prop_put_size(buf, count);
1412                                 usb_ext_prop_put_type(buf, ext_prop->type);
1413                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1414                                                             ext_prop->name_len);
1415                                 if (ret < 0)
1416                                         return ret;
1417                                 switch (ext_prop->type) {
1418                                 case USB_EXT_PROP_UNICODE:
1419                                 case USB_EXT_PROP_UNICODE_ENV:
1420                                 case USB_EXT_PROP_UNICODE_LINK:
1421                                         usb_ext_prop_put_unicode(buf, ret,
1422                                                          ext_prop->data,
1423                                                          ext_prop->data_len);
1424                                         break;
1425                                 case USB_EXT_PROP_BINARY:
1426                                         usb_ext_prop_put_binary(buf, ret,
1427                                                         ext_prop->data,
1428                                                         ext_prop->data_len);
1429                                         break;
1430                                 case USB_EXT_PROP_LE32:
1431                                         /* not implemented */
1432                                 case USB_EXT_PROP_BE32:
1433                                         /* not implemented */
1434                                 default:
1435                                         return -EINVAL;
1436                                 }
1437                                 buf += count;
1438                         }
1439         }
1440
1441         return 0;
1442 }
1443
1444 /*
1445  * The setup() callback implements all the ep0 functionality that's
1446  * not handled lower down, in hardware or the hardware driver(like
1447  * device and endpoint feature flags, and their status).  It's all
1448  * housekeeping for the gadget function we're implementing.  Most of
1449  * the work is in config and function specific setup.
1450  */
1451 int
1452 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1453 {
1454         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1455         struct usb_request              *req = cdev->req;
1456         int                             value = -EOPNOTSUPP;
1457         int                             status = 0;
1458         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1459         u8                              intf = w_index & 0xFF;
1460         u16                             w_value = le16_to_cpu(ctrl->wValue);
1461         u16                             w_length = le16_to_cpu(ctrl->wLength);
1462         struct usb_function             *f = NULL;
1463         u8                              endp;
1464
1465         /* partial re-init of the response message; the function or the
1466          * gadget might need to intercept e.g. a control-OUT completion
1467          * when we delegate to it.
1468          */
1469         req->zero = 0;
1470         req->context = cdev;
1471         req->complete = composite_setup_complete;
1472         req->length = 0;
1473         gadget->ep0->driver_data = cdev;
1474
1475         /*
1476          * Don't let non-standard requests match any of the cases below
1477          * by accident.
1478          */
1479         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1480                 goto unknown;
1481
1482         switch (ctrl->bRequest) {
1483
1484         /* we handle all standard USB descriptors */
1485         case USB_REQ_GET_DESCRIPTOR:
1486                 if (ctrl->bRequestType != USB_DIR_IN)
1487                         goto unknown;
1488                 switch (w_value >> 8) {
1489
1490                 case USB_DT_DEVICE:
1491                         cdev->desc.bNumConfigurations =
1492                                 count_configs(cdev, USB_DT_DEVICE);
1493                         cdev->desc.bMaxPacketSize0 =
1494                                 cdev->gadget->ep0->maxpacket;
1495                         if (gadget_is_superspeed(gadget)) {
1496                                 if (gadget->speed >= USB_SPEED_SUPER) {
1497                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1498                                         cdev->desc.bMaxPacketSize0 = 9;
1499                                 } else {
1500                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1501                                 }
1502                         }
1503
1504                         value = min(w_length, (u16) sizeof cdev->desc);
1505                         memcpy(req->buf, &cdev->desc, value);
1506                         break;
1507                 case USB_DT_DEVICE_QUALIFIER:
1508                         if (!gadget_is_dualspeed(gadget) ||
1509                             gadget->speed >= USB_SPEED_SUPER)
1510                                 break;
1511                         device_qual(cdev);
1512                         value = min_t(int, w_length,
1513                                 sizeof(struct usb_qualifier_descriptor));
1514                         break;
1515                 case USB_DT_OTHER_SPEED_CONFIG:
1516                         if (!gadget_is_dualspeed(gadget) ||
1517                             gadget->speed >= USB_SPEED_SUPER)
1518                                 break;
1519                         /* FALLTHROUGH */
1520                 case USB_DT_CONFIG:
1521                         value = config_desc(cdev, w_value);
1522                         if (value >= 0)
1523                                 value = min(w_length, (u16) value);
1524                         break;
1525                 case USB_DT_STRING:
1526                         value = get_string(cdev, req->buf,
1527                                         w_index, w_value & 0xff);
1528                         if (value >= 0)
1529                                 value = min(w_length, (u16) value);
1530                         break;
1531                 case USB_DT_BOS:
1532                         if (gadget_is_superspeed(gadget)) {
1533                                 value = bos_desc(cdev);
1534                                 value = min(w_length, (u16) value);
1535                         }
1536                         break;
1537                 }
1538                 break;
1539
1540         /* any number of configs can work */
1541         case USB_REQ_SET_CONFIGURATION:
1542                 if (ctrl->bRequestType != 0)
1543                         goto unknown;
1544                 if (gadget_is_otg(gadget)) {
1545                         if (gadget->a_hnp_support)
1546                                 DBG(cdev, "HNP available\n");
1547                         else if (gadget->a_alt_hnp_support)
1548                                 DBG(cdev, "HNP on another port\n");
1549                         else
1550                                 VDBG(cdev, "HNP inactive\n");
1551                 }
1552                 spin_lock(&cdev->lock);
1553                 value = set_config(cdev, ctrl, w_value);
1554                 spin_unlock(&cdev->lock);
1555                 break;
1556         case USB_REQ_GET_CONFIGURATION:
1557                 if (ctrl->bRequestType != USB_DIR_IN)
1558                         goto unknown;
1559                 if (cdev->config)
1560                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1561                 else
1562                         *(u8 *)req->buf = 0;
1563                 value = min(w_length, (u16) 1);
1564                 break;
1565
1566         /* function drivers must handle get/set altsetting; if there's
1567          * no get() method, we know only altsetting zero works.
1568          */
1569         case USB_REQ_SET_INTERFACE:
1570                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1571                         goto unknown;
1572                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1573                         break;
1574                 f = cdev->config->interface[intf];
1575                 if (!f)
1576                         break;
1577                 if (w_value && !f->set_alt)
1578                         break;
1579                 value = f->set_alt(f, w_index, w_value);
1580                 if (value == USB_GADGET_DELAYED_STATUS) {
1581                         DBG(cdev,
1582                          "%s: interface %d (%s) requested delayed status\n",
1583                                         __func__, intf, f->name);
1584                         cdev->delayed_status++;
1585                         DBG(cdev, "delayed_status count %d\n",
1586                                         cdev->delayed_status);
1587                 }
1588                 break;
1589         case USB_REQ_GET_INTERFACE:
1590                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1591                         goto unknown;
1592                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1593                         break;
1594                 f = cdev->config->interface[intf];
1595                 if (!f)
1596                         break;
1597                 /* lots of interfaces only need altsetting zero... */
1598                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1599                 if (value < 0)
1600                         break;
1601                 *((u8 *)req->buf) = value;
1602                 value = min(w_length, (u16) 1);
1603                 break;
1604
1605         /*
1606          * USB 3.0 additions:
1607          * Function driver should handle get_status request. If such cb
1608          * wasn't supplied we respond with default value = 0
1609          * Note: function driver should supply such cb only for the first
1610          * interface of the function
1611          */
1612         case USB_REQ_GET_STATUS:
1613                 if (!gadget_is_superspeed(gadget))
1614                         goto unknown;
1615                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1616                         goto unknown;
1617                 value = 2;      /* This is the length of the get_status reply */
1618                 put_unaligned_le16(0, req->buf);
1619                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1620                         break;
1621                 f = cdev->config->interface[intf];
1622                 if (!f)
1623                         break;
1624                 status = f->get_status ? f->get_status(f) : 0;
1625                 if (status < 0)
1626                         break;
1627                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1628                 break;
1629         /*
1630          * Function drivers should handle SetFeature/ClearFeature
1631          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1632          * only for the first interface of the function
1633          */
1634         case USB_REQ_CLEAR_FEATURE:
1635         case USB_REQ_SET_FEATURE:
1636                 if (!gadget_is_superspeed(gadget))
1637                         goto unknown;
1638                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1639                         goto unknown;
1640                 switch (w_value) {
1641                 case USB_INTRF_FUNC_SUSPEND:
1642                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1643                                 break;
1644                         f = cdev->config->interface[intf];
1645                         if (!f)
1646                                 break;
1647                         value = 0;
1648                         if (f->func_suspend)
1649                                 value = f->func_suspend(f, w_index >> 8);
1650                         if (value < 0) {
1651                                 ERROR(cdev,
1652                                       "func_suspend() returned error %d\n",
1653                                       value);
1654                                 value = 0;
1655                         }
1656                         break;
1657                 }
1658                 break;
1659         default:
1660 unknown:
1661                 /*
1662                  * OS descriptors handling
1663                  */
1664                 if (cdev->use_os_string && cdev->os_desc_config &&
1665                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1666                     ctrl->bRequest == cdev->b_vendor_code) {
1667                         struct usb_request              *req;
1668                         struct usb_configuration        *os_desc_cfg;
1669                         u8                              *buf;
1670                         int                             interface;
1671                         int                             count = 0;
1672
1673                         req = cdev->os_desc_req;
1674                         req->context = cdev;
1675                         req->complete = composite_setup_complete;
1676                         buf = req->buf;
1677                         os_desc_cfg = cdev->os_desc_config;
1678                         memset(buf, 0, w_length);
1679                         buf[5] = 0x01;
1680                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1681                         case USB_RECIP_DEVICE:
1682                                 if (w_index != 0x4 || (w_value >> 8))
1683                                         break;
1684                                 buf[6] = w_index;
1685                                 if (w_length == 0x10) {
1686                                         /* Number of ext compat interfaces */
1687                                         count = count_ext_compat(os_desc_cfg);
1688                                         buf[8] = count;
1689                                         count *= 24; /* 24 B/ext compat desc */
1690                                         count += 16; /* header */
1691                                         put_unaligned_le32(count, buf);
1692                                         value = w_length;
1693                                 } else {
1694                                         /* "extended compatibility ID"s */
1695                                         count = count_ext_compat(os_desc_cfg);
1696                                         buf[8] = count;
1697                                         count *= 24; /* 24 B/ext compat desc */
1698                                         count += 16; /* header */
1699                                         put_unaligned_le32(count, buf);
1700                                         buf += 16;
1701                                         fill_ext_compat(os_desc_cfg, buf);
1702                                         value = w_length;
1703                                 }
1704                                 break;
1705                         case USB_RECIP_INTERFACE:
1706                                 if (w_index != 0x5 || (w_value >> 8))
1707                                         break;
1708                                 interface = w_value & 0xFF;
1709                                 buf[6] = w_index;
1710                                 if (w_length == 0x0A) {
1711                                         count = count_ext_prop(os_desc_cfg,
1712                                                 interface);
1713                                         put_unaligned_le16(count, buf + 8);
1714                                         count = len_ext_prop(os_desc_cfg,
1715                                                 interface);
1716                                         put_unaligned_le32(count, buf);
1717
1718                                         value = w_length;
1719                                 } else {
1720                                         count = count_ext_prop(os_desc_cfg,
1721                                                 interface);
1722                                         put_unaligned_le16(count, buf + 8);
1723                                         count = len_ext_prop(os_desc_cfg,
1724                                                 interface);
1725                                         put_unaligned_le32(count, buf);
1726                                         buf += 10;
1727                                         value = fill_ext_prop(os_desc_cfg,
1728                                                               interface, buf);
1729                                         if (value < 0)
1730                                                 return value;
1731
1732                                         value = w_length;
1733                                 }
1734                                 break;
1735                         }
1736                         req->length = value;
1737                         req->context = cdev;
1738                         req->zero = value < w_length;
1739                         value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1740                         if (value < 0) {
1741                                 DBG(cdev, "ep_queue --> %d\n", value);
1742                                 req->status = 0;
1743                                 composite_setup_complete(gadget->ep0, req);
1744                         }
1745                         return value;
1746                 }
1747
1748                 VDBG(cdev,
1749                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1750                         ctrl->bRequestType, ctrl->bRequest,
1751                         w_value, w_index, w_length);
1752
1753                 /* functions always handle their interfaces and endpoints...
1754                  * punt other recipients (other, WUSB, ...) to the current
1755                  * configuration code.
1756                  *
1757                  * REVISIT it could make sense to let the composite device
1758                  * take such requests too, if that's ever needed:  to work
1759                  * in config 0, etc.
1760                  */
1761                 if (cdev->config) {
1762                         list_for_each_entry(f, &cdev->config->functions, list)
1763                                 if (f->req_match && f->req_match(f, ctrl))
1764                                         goto try_fun_setup;
1765                         f = NULL;
1766                 }
1767
1768                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1769                 case USB_RECIP_INTERFACE:
1770                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1771                                 break;
1772                         f = cdev->config->interface[intf];
1773                         break;
1774
1775                 case USB_RECIP_ENDPOINT:
1776                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1777                         list_for_each_entry(f, &cdev->config->functions, list) {
1778                                 if (test_bit(endp, f->endpoints))
1779                                         break;
1780                         }
1781                         if (&f->list == &cdev->config->functions)
1782                                 f = NULL;
1783                         break;
1784                 }
1785 try_fun_setup:
1786                 if (f && f->setup)
1787                         value = f->setup(f, ctrl);
1788                 else {
1789                         struct usb_configuration        *c;
1790
1791                         c = cdev->config;
1792                         if (!c)
1793                                 goto done;
1794
1795                         /* try current config's setup */
1796                         if (c->setup) {
1797                                 value = c->setup(c, ctrl);
1798                                 goto done;
1799                         }
1800
1801                         /* try the only function in the current config */
1802                         if (!list_is_singular(&c->functions))
1803                                 goto done;
1804                         f = list_first_entry(&c->functions, struct usb_function,
1805                                              list);
1806                         if (f->setup)
1807                                 value = f->setup(f, ctrl);
1808                 }
1809
1810                 goto done;
1811         }
1812
1813         /* respond with data transfer before status phase? */
1814         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1815                 req->length = value;
1816                 req->context = cdev;
1817                 req->zero = value < w_length;
1818                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1819                 if (value < 0) {
1820                         DBG(cdev, "ep_queue --> %d\n", value);
1821                         req->status = 0;
1822                         composite_setup_complete(gadget->ep0, req);
1823                 }
1824         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1825                 WARN(cdev,
1826                         "%s: Delayed status not supported for w_length != 0",
1827                         __func__);
1828         }
1829
1830 done:
1831         /* device either stalls (value < 0) or reports success */
1832         return value;
1833 }
1834
1835 void composite_disconnect(struct usb_gadget *gadget)
1836 {
1837         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1838         unsigned long                   flags;
1839
1840         /* REVISIT:  should we have config and device level
1841          * disconnect callbacks?
1842          */
1843         spin_lock_irqsave(&cdev->lock, flags);
1844         if (cdev->config)
1845                 reset_config(cdev);
1846         if (cdev->driver->disconnect)
1847                 cdev->driver->disconnect(cdev);
1848         spin_unlock_irqrestore(&cdev->lock, flags);
1849 }
1850
1851 /*-------------------------------------------------------------------------*/
1852
1853 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
1854                               char *buf)
1855 {
1856         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1857         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1858
1859         return sprintf(buf, "%d\n", cdev->suspended);
1860 }
1861 static DEVICE_ATTR_RO(suspended);
1862
1863 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1864 {
1865         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1866
1867         /* composite_disconnect() must already have been called
1868          * by the underlying peripheral controller driver!
1869          * so there's no i/o concurrency that could affect the
1870          * state protected by cdev->lock.
1871          */
1872         WARN_ON(cdev->config);
1873
1874         while (!list_empty(&cdev->configs)) {
1875                 struct usb_configuration        *c;
1876                 c = list_first_entry(&cdev->configs,
1877                                 struct usb_configuration, list);
1878                 remove_config(cdev, c);
1879         }
1880         if (cdev->driver->unbind && unbind_driver)
1881                 cdev->driver->unbind(cdev);
1882
1883         composite_dev_cleanup(cdev);
1884
1885         kfree(cdev->def_manufacturer);
1886         kfree(cdev);
1887         set_gadget_data(gadget, NULL);
1888 }
1889
1890 static void composite_unbind(struct usb_gadget *gadget)
1891 {
1892         __composite_unbind(gadget, true);
1893 }
1894
1895 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1896                 const struct usb_device_descriptor *old)
1897 {
1898         __le16 idVendor;
1899         __le16 idProduct;
1900         __le16 bcdDevice;
1901         u8 iSerialNumber;
1902         u8 iManufacturer;
1903         u8 iProduct;
1904
1905         /*
1906          * these variables may have been set in
1907          * usb_composite_overwrite_options()
1908          */
1909         idVendor = new->idVendor;
1910         idProduct = new->idProduct;
1911         bcdDevice = new->bcdDevice;
1912         iSerialNumber = new->iSerialNumber;
1913         iManufacturer = new->iManufacturer;
1914         iProduct = new->iProduct;
1915
1916         *new = *old;
1917         if (idVendor)
1918                 new->idVendor = idVendor;
1919         if (idProduct)
1920                 new->idProduct = idProduct;
1921         if (bcdDevice)
1922                 new->bcdDevice = bcdDevice;
1923         else
1924                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1925         if (iSerialNumber)
1926                 new->iSerialNumber = iSerialNumber;
1927         if (iManufacturer)
1928                 new->iManufacturer = iManufacturer;
1929         if (iProduct)
1930                 new->iProduct = iProduct;
1931 }
1932
1933 int composite_dev_prepare(struct usb_composite_driver *composite,
1934                 struct usb_composite_dev *cdev)
1935 {
1936         struct usb_gadget *gadget = cdev->gadget;
1937         int ret = -ENOMEM;
1938
1939         /* preallocate control response and buffer */
1940         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1941         if (!cdev->req)
1942                 return -ENOMEM;
1943
1944         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
1945         if (!cdev->req->buf)
1946                 goto fail;
1947
1948         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
1949         if (ret)
1950                 goto fail_dev;
1951
1952         cdev->req->complete = composite_setup_complete;
1953         cdev->req->context = cdev;
1954         gadget->ep0->driver_data = cdev;
1955
1956         cdev->driver = composite;
1957
1958         /*
1959          * As per USB compliance update, a device that is actively drawing
1960          * more than 100mA from USB must report itself as bus-powered in
1961          * the GetStatus(DEVICE) call.
1962          */
1963         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1964                 usb_gadget_set_selfpowered(gadget);
1965
1966         /* interface and string IDs start at zero via kzalloc.
1967          * we force endpoints to start unassigned; few controller
1968          * drivers will zero ep->driver_data.
1969          */
1970         usb_ep_autoconfig_reset(gadget);
1971         return 0;
1972 fail_dev:
1973         kfree(cdev->req->buf);
1974 fail:
1975         usb_ep_free_request(gadget->ep0, cdev->req);
1976         cdev->req = NULL;
1977         return ret;
1978 }
1979
1980 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1981                                   struct usb_ep *ep0)
1982 {
1983         int ret = 0;
1984
1985         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
1986         if (!cdev->os_desc_req) {
1987                 ret = PTR_ERR(cdev->os_desc_req);
1988                 goto end;
1989         }
1990
1991         /* OS feature descriptor length <= 4kB */
1992         cdev->os_desc_req->buf = kmalloc(4096, GFP_KERNEL);
1993         if (!cdev->os_desc_req->buf) {
1994                 ret = PTR_ERR(cdev->os_desc_req->buf);
1995                 kfree(cdev->os_desc_req);
1996                 goto end;
1997         }
1998         cdev->os_desc_req->context = cdev;
1999         cdev->os_desc_req->complete = composite_setup_complete;
2000 end:
2001         return ret;
2002 }
2003
2004 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2005 {
2006         struct usb_gadget_string_container *uc, *tmp;
2007
2008         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2009                 list_del(&uc->list);
2010                 kfree(uc);
2011         }
2012         if (cdev->os_desc_req) {
2013                 if (cdev->os_desc_pending)
2014                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2015
2016                 kfree(cdev->os_desc_req->buf);
2017                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2018         }
2019         if (cdev->req) {
2020                 if (cdev->setup_pending)
2021                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2022
2023                 kfree(cdev->req->buf);
2024                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2025         }
2026         cdev->next_string_id = 0;
2027         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2028 }
2029
2030 static int composite_bind(struct usb_gadget *gadget,
2031                 struct usb_gadget_driver *gdriver)
2032 {
2033         struct usb_composite_dev        *cdev;
2034         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2035         int                             status = -ENOMEM;
2036
2037         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2038         if (!cdev)
2039                 return status;
2040
2041         spin_lock_init(&cdev->lock);
2042         cdev->gadget = gadget;
2043         set_gadget_data(gadget, cdev);
2044         INIT_LIST_HEAD(&cdev->configs);
2045         INIT_LIST_HEAD(&cdev->gstrings);
2046
2047         status = composite_dev_prepare(composite, cdev);
2048         if (status)
2049                 goto fail;
2050
2051         /* composite gadget needs to assign strings for whole device (like
2052          * serial number), register function drivers, potentially update
2053          * power state and consumption, etc
2054          */
2055         status = composite->bind(cdev);
2056         if (status < 0)
2057                 goto fail;
2058
2059         if (cdev->use_os_string) {
2060                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2061                 if (status)
2062                         goto fail;
2063         }
2064
2065         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2066
2067         /* has userspace failed to provide a serial number? */
2068         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2069                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2070
2071         INFO(cdev, "%s ready\n", composite->name);
2072         return 0;
2073
2074 fail:
2075         __composite_unbind(gadget, false);
2076         return status;
2077 }
2078
2079 /*-------------------------------------------------------------------------*/
2080
2081 void composite_suspend(struct usb_gadget *gadget)
2082 {
2083         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2084         struct usb_function             *f;
2085
2086         /* REVISIT:  should we have config level
2087          * suspend/resume callbacks?
2088          */
2089         DBG(cdev, "suspend\n");
2090         if (cdev->config) {
2091                 list_for_each_entry(f, &cdev->config->functions, list) {
2092                         if (f->suspend)
2093                                 f->suspend(f);
2094                 }
2095         }
2096         if (cdev->driver->suspend)
2097                 cdev->driver->suspend(cdev);
2098
2099         cdev->suspended = 1;
2100
2101         usb_gadget_vbus_draw(gadget, 2);
2102 }
2103
2104 void composite_resume(struct usb_gadget *gadget)
2105 {
2106         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2107         struct usb_function             *f;
2108         u16                             maxpower;
2109
2110         /* REVISIT:  should we have config level
2111          * suspend/resume callbacks?
2112          */
2113         DBG(cdev, "resume\n");
2114         if (cdev->driver->resume)
2115                 cdev->driver->resume(cdev);
2116         if (cdev->config) {
2117                 list_for_each_entry(f, &cdev->config->functions, list) {
2118                         if (f->resume)
2119                                 f->resume(f);
2120                 }
2121
2122                 maxpower = cdev->config->MaxPower;
2123
2124                 usb_gadget_vbus_draw(gadget, maxpower ?
2125                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
2126         }
2127
2128         cdev->suspended = 0;
2129 }
2130
2131 /*-------------------------------------------------------------------------*/
2132
2133 static const struct usb_gadget_driver composite_driver_template = {
2134         .bind           = composite_bind,
2135         .unbind         = composite_unbind,
2136
2137         .setup          = composite_setup,
2138         .reset          = composite_disconnect,
2139         .disconnect     = composite_disconnect,
2140
2141         .suspend        = composite_suspend,
2142         .resume         = composite_resume,
2143
2144         .driver = {
2145                 .owner          = THIS_MODULE,
2146         },
2147 };
2148
2149 /**
2150  * usb_composite_probe() - register a composite driver
2151  * @driver: the driver to register
2152  *
2153  * Context: single threaded during gadget setup
2154  *
2155  * This function is used to register drivers using the composite driver
2156  * framework.  The return value is zero, or a negative errno value.
2157  * Those values normally come from the driver's @bind method, which does
2158  * all the work of setting up the driver to match the hardware.
2159  *
2160  * On successful return, the gadget is ready to respond to requests from
2161  * the host, unless one of its components invokes usb_gadget_disconnect()
2162  * while it was binding.  That would usually be done in order to wait for
2163  * some userspace participation.
2164  */
2165 int usb_composite_probe(struct usb_composite_driver *driver)
2166 {
2167         struct usb_gadget_driver *gadget_driver;
2168
2169         if (!driver || !driver->dev || !driver->bind)
2170                 return -EINVAL;
2171
2172         if (!driver->name)
2173                 driver->name = "composite";
2174
2175         driver->gadget_driver = composite_driver_template;
2176         gadget_driver = &driver->gadget_driver;
2177
2178         gadget_driver->function =  (char *) driver->name;
2179         gadget_driver->driver.name = driver->name;
2180         gadget_driver->max_speed = driver->max_speed;
2181
2182         return usb_gadget_probe_driver(gadget_driver);
2183 }
2184 EXPORT_SYMBOL_GPL(usb_composite_probe);
2185
2186 /**
2187  * usb_composite_unregister() - unregister a composite driver
2188  * @driver: the driver to unregister
2189  *
2190  * This function is used to unregister drivers using the composite
2191  * driver framework.
2192  */
2193 void usb_composite_unregister(struct usb_composite_driver *driver)
2194 {
2195         usb_gadget_unregister_driver(&driver->gadget_driver);
2196 }
2197 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2198
2199 /**
2200  * usb_composite_setup_continue() - Continue with the control transfer
2201  * @cdev: the composite device who's control transfer was kept waiting
2202  *
2203  * This function must be called by the USB function driver to continue
2204  * with the control transfer's data/status stage in case it had requested to
2205  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2206  * can request the composite framework to delay the setup request's data/status
2207  * stages by returning USB_GADGET_DELAYED_STATUS.
2208  */
2209 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2210 {
2211         int                     value;
2212         struct usb_request      *req = cdev->req;
2213         unsigned long           flags;
2214
2215         DBG(cdev, "%s\n", __func__);
2216         spin_lock_irqsave(&cdev->lock, flags);
2217
2218         if (cdev->delayed_status == 0) {
2219                 WARN(cdev, "%s: Unexpected call\n", __func__);
2220
2221         } else if (--cdev->delayed_status == 0) {
2222                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2223                 req->length = 0;
2224                 req->context = cdev;
2225                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2226                 if (value < 0) {
2227                         DBG(cdev, "ep_queue --> %d\n", value);
2228                         req->status = 0;
2229                         composite_setup_complete(cdev->gadget->ep0, req);
2230                 }
2231         }
2232
2233         spin_unlock_irqrestore(&cdev->lock, flags);
2234 }
2235 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2236
2237 static char *composite_default_mfr(struct usb_gadget *gadget)
2238 {
2239         char *mfr;
2240         int len;
2241
2242         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
2243                         init_utsname()->release, gadget->name);
2244         len++;
2245         mfr = kmalloc(len, GFP_KERNEL);
2246         if (!mfr)
2247                 return NULL;
2248         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
2249                         init_utsname()->release, gadget->name);
2250         return mfr;
2251 }
2252
2253 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2254                 struct usb_composite_overwrite *covr)
2255 {
2256         struct usb_device_descriptor    *desc = &cdev->desc;
2257         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2258         struct usb_string               *dev_str = gstr->strings;
2259
2260         if (covr->idVendor)
2261                 desc->idVendor = cpu_to_le16(covr->idVendor);
2262
2263         if (covr->idProduct)
2264                 desc->idProduct = cpu_to_le16(covr->idProduct);
2265
2266         if (covr->bcdDevice)
2267                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2268
2269         if (covr->serial_number) {
2270                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2271                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2272         }
2273         if (covr->manufacturer) {
2274                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2275                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2276
2277         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2278                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2279                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2280                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2281         }
2282
2283         if (covr->product) {
2284                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2285                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2286         }
2287 }
2288 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2289
2290 MODULE_LICENSE("GPL");
2291 MODULE_AUTHOR("David Brownell");