drivers/usb/gadget/composite.c

   1 /*
   2  * composite.c - infrastructure for Composite USB Gadgets
   3  *
   4  * Copyright (C) 2006-2008 David Brownell
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 /* #define VERBOSE_DEBUG */
  13
  14 #include <linux/kallsyms.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/device.h>
  19 #include <linux/utsname.h>
  20
  21 #include <linux/usb/composite.h>
  22 #include <linux/usb/otg.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "u_os_desc.h"
  26
  27 /**
  28  * struct usb_os_string - represents OS String to be reported by a gadget
  29  * @bLength: total length of the entire descritor, always 0x12
  30  * @bDescriptorType: USB_DT_STRING
  31  * @qwSignature: the OS String proper
  32  * @bMS_VendorCode: code used by the host for subsequent requests
  33  * @bPad: not used, must be zero
  34  */
  35 struct usb_os_string {
  36         __u8    bLength;
  37         __u8    bDescriptorType;
  38         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  39         __u8    bMS_VendorCode;
  40         __u8    bPad;
  41 } __packed;
  42
  43 /*
  44  * The code in this file is utility code, used to build a gadget driver
  45  * from one or more "function" drivers, one or more "configuration"
  46  * objects, and a "usb_composite_driver" by gluing them together along
  47  * with the relevant device-wide data.
  48  */
  49
  50 static struct usb_gadget_strings **get_containers_gs(
  51                 struct usb_gadget_string_container *uc)
  52 {
  53         return (struct usb_gadget_strings **)uc->stash;
  54 }
  55
  56 /**
  57  * function_descriptors() - get function descriptors for speed
  58  * @f: the function
  59  * @speed: the speed
  60  *
  61  * Returns the descriptors or NULL if not set.
  62  */
  63 static struct usb_descriptor_header **
  64 function_descriptors(struct usb_function *f,
  65                      enum usb_device_speed speed)
  66 {
  67         struct usb_descriptor_header **descriptors;
  68
  69         /*
  70          * NOTE: we try to help gadget drivers which might not be setting
  71          * max_speed appropriately.
  72          */
  73
  74         switch (speed) {
  75         case USB_SPEED_SUPER_PLUS:
  76                 descriptors = f->ssp_descriptors;
  77                 if (descriptors)
  78                         break;
  79                 /* FALLTHROUGH */
  80         case USB_SPEED_SUPER:
  81                 descriptors = f->ss_descriptors;
  82                 if (descriptors)
  83                         break;
  84                 /* FALLTHROUGH */
  85         case USB_SPEED_HIGH:
  86                 descriptors = f->hs_descriptors;
  87                 if (descriptors)
  88                         break;
  89                 /* FALLTHROUGH */
  90         default:
  91                 descriptors = f->fs_descriptors;
  92         }
  93
  94         /*
  95          * if we can't find any descriptors at all, then this gadget deserves to
  96          * Oops with a NULL pointer dereference
  97          */
  98
  99         return descriptors;
 100 }
 101
 102 /**
 103  * next_ep_desc() - advance to the next EP descriptor
 104  * @t: currect pointer within descriptor array
 105  *
 106  * Return: next EP descriptor or NULL
 107  *
 108  * Iterate over @t until either EP descriptor found or
 109  * NULL (that indicates end of list) encountered
 110  */
 111 static struct usb_descriptor_header**
 112 next_ep_desc(struct usb_descriptor_header **t)
 113 {
 114         for (; *t; t++) {
 115                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
 116                         return t;
 117         }
 118         return NULL;
 119 }
 120
 121 /*
 122  * for_each_ep_desc()- iterate over endpoint descriptors in the
 123  *              descriptors list
 124  * @start:      pointer within descriptor array.
 125  * @ep_desc:    endpoint descriptor to use as the loop cursor
 126  */
 127 #define for_each_ep_desc(start, ep_desc) \
 128         for (ep_desc = next_ep_desc(start); \
 129               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
 130
 131 /**
 132  * config_ep_by_speed() - configures the given endpoint
 133  * according to gadget speed.
 134  * @g: pointer to the gadget
 135  * @f: usb function
 136  * @_ep: the endpoint to configure
 137  *
 138  * Return: error code, 0 on success
 139  *
 140  * This function chooses the right descriptors for a given
 141  * endpoint according to gadget speed and saves it in the
 142  * endpoint desc field. If the endpoint already has a descriptor
 143  * assigned to it - overwrites it with currently corresponding
 144  * descriptor. The endpoint maxpacket field is updated according
 145  * to the chosen descriptor.
 146  * Note: the supplied function should hold all the descriptors
 147  * for supported speeds
 148  */
 149 int config_ep_by_speed(struct usb_gadget *g,
 150                         struct usb_function *f,
 151                         struct usb_ep *_ep)
 152 {
 153         struct usb_composite_dev        *cdev = get_gadget_data(g);
 154         struct usb_endpoint_descriptor *chosen_desc = NULL;
 155         struct usb_descriptor_header **speed_desc = NULL;
 156
 157         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 158         int want_comp_desc = 0;
 159
 160         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 161
 162         if (!g || !f || !_ep)
 163                 return -EIO;
 164
 165         /* select desired speed */
 166         switch (g->speed) {
 167         case USB_SPEED_SUPER_PLUS:
 168                 if (gadget_is_superspeed_plus(g)) {
 169                         speed_desc = f->ssp_descriptors;
 170                         want_comp_desc = 1;
 171                         break;
 172                 }
 173                 /* else: Fall trough */
 174         case USB_SPEED_SUPER:
 175                 if (gadget_is_superspeed(g)) {
 176                         speed_desc = f->ss_descriptors;
 177                         want_comp_desc = 1;
 178                         break;
 179                 }
 180                 /* else: Fall trough */
 181         case USB_SPEED_HIGH:
 182                 if (gadget_is_dualspeed(g)) {
 183                         speed_desc = f->hs_descriptors;
 184                         break;
 185                 }
 186                 /* else: fall through */
 187         default:
 188                 speed_desc = f->fs_descriptors;
 189         }
 190         /* find descriptors */
 191         for_each_ep_desc(speed_desc, d_spd) {
 192                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 193                 if (chosen_desc->bEndpointAddress == _ep->address)
 194                         goto ep_found;
 195         }
 196         return -EIO;
 197
 198 ep_found:
 199         /* commit results */
 200         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 201         _ep->desc = chosen_desc;
 202         _ep->comp_desc = NULL;
 203         _ep->maxburst = 0;
 204         _ep->mult = 1;
 205
 206         if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 207                                 usb_endpoint_xfer_int(_ep->desc)))
 208                 _ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 209
 210         if (!want_comp_desc)
 211                 return 0;
 212
 213         /*
 214          * Companion descriptor should follow EP descriptor
 215          * USB 3.0 spec, #9.6.7
 216          */
 217         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 218         if (!comp_desc ||
 219             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 220                 return -EIO;
 221         _ep->comp_desc = comp_desc;
 222         if (g->speed >= USB_SPEED_SUPER) {
 223                 switch (usb_endpoint_type(_ep->desc)) {
 224                 case USB_ENDPOINT_XFER_ISOC:
 225                         /* mult: bits 1:0 of bmAttributes */
 226                         _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 227                 case USB_ENDPOINT_XFER_BULK:
 228                 case USB_ENDPOINT_XFER_INT:
 229                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 230                         break;
 231                 default:
 232                         if (comp_desc->bMaxBurst != 0)
 233                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 234                         _ep->maxburst = 1;
 235                         break;
 236                 }
 237         }
 238         return 0;
 239 }
 240 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 241
 242 /**
 243  * usb_add_function() - add a function to a configuration
 244  * @config: the configuration
 245  * @function: the function being added
 246  * Context: single threaded during gadget setup
 247  *
 248  * After initialization, each configuration must have one or more
 249  * functions added to it.  Adding a function involves calling its @bind()
 250  * method to allocate resources such as interface and string identifiers
 251  * and endpoints.
 252  *
 253  * This function returns the value of the function's bind(), which is
 254  * zero for success else a negative errno value.
 255  */
 256 int usb_add_function(struct usb_configuration *config,
 257                 struct usb_function *function)
 258 {
 259         int     value = -EINVAL;
 260
 261         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 262                         function->name, function,
 263                         config->label, config);
 264
 265         if (!function->set_alt || !function->disable)
 266                 goto done;
 267
 268         function->config = config;
 269         list_add_tail(&function->list, &config->functions);
 270
 271         if (function->bind_deactivated) {
 272                 value = usb_function_deactivate(function);
 273                 if (value)
 274                         goto done;
 275         }
 276
 277         /* REVISIT *require* function->bind? */
 278         if (function->bind) {
 279                 value = function->bind(config, function);
 280                 if (value < 0) {
 281                         list_del(&function->list);
 282                         function->config = NULL;
 283                 }
 284         } else
 285                 value = 0;
 286
 287         /* We allow configurations that don't work at both speeds.
 288          * If we run into a lowspeed Linux system, treat it the same
 289          * as full speed ... it's the function drivers that will need
 290          * to avoid bulk and ISO transfers.
 291          */
 292         if (!config->fullspeed && function->fs_descriptors)
 293                 config->fullspeed = true;
 294         if (!config->highspeed && function->hs_descriptors)
 295                 config->highspeed = true;
 296         if (!config->superspeed && function->ss_descriptors)
 297                 config->superspeed = true;
 298         if (!config->superspeed_plus && function->ssp_descriptors)
 299                 config->superspeed_plus = true;
 300
 301 done:
 302         if (value)
 303                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 304                                 function->name, function, value);
 305         return value;
 306 }
 307 EXPORT_SYMBOL_GPL(usb_add_function);
 308
 309 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 310 {
 311         if (f->disable)
 312                 f->disable(f);
 313
 314         bitmap_zero(f->endpoints, 32);
 315         list_del(&f->list);
 316         if (f->unbind)
 317                 f->unbind(c, f);
 318
 319         if (f->bind_deactivated)
 320                 usb_function_activate(f);
 321 }
 322 EXPORT_SYMBOL_GPL(usb_remove_function);
 323
 324 /**
 325  * usb_function_deactivate - prevent function and gadget enumeration
 326  * @function: the function that isn't yet ready to respond
 327  *
 328  * Blocks response of the gadget driver to host enumeration by
 329  * preventing the data line pullup from being activated.  This is
 330  * normally called during @bind() processing to change from the
 331  * initial "ready to respond" state, or when a required resource
 332  * becomes available.
 333  *
 334  * For example, drivers that serve as a passthrough to a userspace
 335  * daemon can block enumeration unless that daemon (such as an OBEX,
 336  * MTP, or print server) is ready to handle host requests.
 337  *
 338  * Not all systems support software control of their USB peripheral
 339  * data pullups.
 340  *
 341  * Returns zero on success, else negative errno.
 342  */
 343 int usb_function_deactivate(struct usb_function *function)
 344 {
 345         struct usb_composite_dev        *cdev = function->config->cdev;
 346         unsigned long                   flags;
 347         int                             status = 0;
 348
 349         spin_lock_irqsave(&cdev->lock, flags);
 350
 351         if (cdev->deactivations == 0)
 352                 status = usb_gadget_deactivate(cdev->gadget);
 353         if (status == 0)
 354                 cdev->deactivations++;
 355
 356         spin_unlock_irqrestore(&cdev->lock, flags);
 357         return status;
 358 }
 359 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 360
 361 /**
 362  * usb_function_activate - allow function and gadget enumeration
 363  * @function: function on which usb_function_activate() was called
 364  *
 365  * Reverses effect of usb_function_deactivate().  If no more functions
 366  * are delaying their activation, the gadget driver will respond to
 367  * host enumeration procedures.
 368  *
 369  * Returns zero on success, else negative errno.
 370  */
 371 int usb_function_activate(struct usb_function *function)
 372 {
 373         struct usb_composite_dev        *cdev = function->config->cdev;
 374         unsigned long                   flags;
 375         int                             status = 0;
 376
 377         spin_lock_irqsave(&cdev->lock, flags);
 378
 379         if (WARN_ON(cdev->deactivations == 0))
 380                 status = -EINVAL;
 381         else {
 382                 cdev->deactivations--;
 383                 if (cdev->deactivations == 0)
 384                         status = usb_gadget_activate(cdev->gadget);
 385         }
 386
 387         spin_unlock_irqrestore(&cdev->lock, flags);
 388         return status;
 389 }
 390 EXPORT_SYMBOL_GPL(usb_function_activate);
 391
 392 /**
 393  * usb_interface_id() - allocate an unused interface ID
 394  * @config: configuration associated with the interface
 395  * @function: function handling the interface
 396  * Context: single threaded during gadget setup
 397  *
 398  * usb_interface_id() is called from usb_function.bind() callbacks to
 399  * allocate new interface IDs.  The function driver will then store that
 400  * ID in interface, association, CDC union, and other descriptors.  It
 401  * will also handle any control requests targeted at that interface,
 402  * particularly changing its altsetting via set_alt().  There may
 403  * also be class-specific or vendor-specific requests to handle.
 404  *
 405  * All interface identifier should be allocated using this routine, to
 406  * ensure that for example different functions don't wrongly assign
 407  * different meanings to the same identifier.  Note that since interface
 408  * identifiers are configuration-specific, functions used in more than
 409  * one configuration (or more than once in a given configuration) need
 410  * multiple versions of the relevant descriptors.
 411  *
 412  * Returns the interface ID which was allocated; or -ENODEV if no
 413  * more interface IDs can be allocated.
 414  */
 415 int usb_interface_id(struct usb_configuration *config,
 416                 struct usb_function *function)
 417 {
 418         unsigned id = config->next_interface_id;
 419
 420         if (id < MAX_CONFIG_INTERFACES) {
 421                 config->interface[id] = function;
 422                 config->next_interface_id = id + 1;
 423                 return id;
 424         }
 425         return -ENODEV;
 426 }
 427 EXPORT_SYMBOL_GPL(usb_interface_id);
 428
 429 static u8 encode_bMaxPower(enum usb_device_speed speed,
 430                 struct usb_configuration *c)
 431 {
 432         unsigned val;
 433
 434         if (c->MaxPower)
 435                 val = c->MaxPower;
 436         else
 437                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 438         if (!val)
 439                 return 0;
 440         switch (speed) {
 441         case USB_SPEED_SUPER:
 442                 return DIV_ROUND_UP(val, 8);
 443         default:
 444                 return DIV_ROUND_UP(val, 2);
 445         }
 446 }
 447
 448 static int config_buf(struct usb_configuration *config,
 449                 enum usb_device_speed speed, void *buf, u8 type)
 450 {
 451         struct usb_config_descriptor    *c = buf;
 452         void                            *next = buf + USB_DT_CONFIG_SIZE;
 453         int                             len;
 454         struct usb_function             *f;
 455         int                             status;
 456
 457         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 458         /* write the config descriptor */
 459         c = buf;
 460         c->bLength = USB_DT_CONFIG_SIZE;
 461         c->bDescriptorType = type;
 462         /* wTotalLength is written later */
 463         c->bNumInterfaces = config->next_interface_id;
 464         c->bConfigurationValue = config->bConfigurationValue;
 465         c->iConfiguration = config->iConfiguration;
 466         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 467         c->bMaxPower = encode_bMaxPower(speed, config);
 468
 469         /* There may be e.g. OTG descriptors */
 470         if (config->descriptors) {
 471                 status = usb_descriptor_fillbuf(next, len,
 472                                 config->descriptors);
 473                 if (status < 0)
 474                         return status;
 475                 len -= status;
 476                 next += status;
 477         }
 478
 479         /* add each function's descriptors */
 480         list_for_each_entry(f, &config->functions, list) {
 481                 struct usb_descriptor_header **descriptors;
 482
 483                 descriptors = function_descriptors(f, speed);
 484                 if (!descriptors)
 485                         continue;
 486                 status = usb_descriptor_fillbuf(next, len,
 487                         (const struct usb_descriptor_header **) descriptors);
 488                 if (status < 0)
 489                         return status;
 490                 len -= status;
 491                 next += status;
 492         }
 493
 494         len = next - buf;
 495         c->wTotalLength = cpu_to_le16(len);
 496         return len;
 497 }
 498
 499 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 500 {
 501         struct usb_gadget               *gadget = cdev->gadget;
 502         struct usb_configuration        *c;
 503         struct list_head                *pos;
 504         u8                              type = w_value >> 8;
 505         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 506
 507         if (gadget->speed >= USB_SPEED_SUPER)
 508                 speed = gadget->speed;
 509         else if (gadget_is_dualspeed(gadget)) {
 510                 int     hs = 0;
 511                 if (gadget->speed == USB_SPEED_HIGH)
 512                         hs = 1;
 513                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 514                         hs = !hs;
 515                 if (hs)
 516                         speed = USB_SPEED_HIGH;
 517
 518         }
 519
 520         /* This is a lookup by config *INDEX* */
 521         w_value &= 0xff;
 522
 523         pos = &cdev->configs;
 524         c = cdev->os_desc_config;
 525         if (c)
 526                 goto check_config;
 527
 528         while ((pos = pos->next) !=  &cdev->configs) {
 529                 c = list_entry(pos, typeof(*c), list);
 530
 531                 /* skip OS Descriptors config which is handled separately */
 532                 if (c == cdev->os_desc_config)
 533                         continue;
 534
 535 check_config:
 536                 /* ignore configs that won't work at this speed */
 537                 switch (speed) {
 538                 case USB_SPEED_SUPER_PLUS:
 539                         if (!c->superspeed_plus)
 540                                 continue;
 541                         break;
 542                 case USB_SPEED_SUPER:
 543                         if (!c->superspeed)
 544                                 continue;
 545                         break;
 546                 case USB_SPEED_HIGH:
 547                         if (!c->highspeed)
 548                                 continue;
 549                         break;
 550                 default:
 551                         if (!c->fullspeed)
 552                                 continue;
 553                 }
 554
 555                 if (w_value == 0)
 556                         return config_buf(c, speed, cdev->req->buf, type);
 557                 w_value--;
 558         }
 559         return -EINVAL;
 560 }
 561
 562 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 563 {
 564         struct usb_gadget               *gadget = cdev->gadget;
 565         struct usb_configuration        *c;
 566         unsigned                        count = 0;
 567         int                             hs = 0;
 568         int                             ss = 0;
 569         int                             ssp = 0;
 570
 571         if (gadget_is_dualspeed(gadget)) {
 572                 if (gadget->speed == USB_SPEED_HIGH)
 573                         hs = 1;
 574                 if (gadget->speed == USB_SPEED_SUPER)
 575                         ss = 1;
 576                 if (gadget->speed == USB_SPEED_SUPER_PLUS)
 577                         ssp = 1;
 578                 if (type == USB_DT_DEVICE_QUALIFIER)
 579                         hs = !hs;
 580         }
 581         list_for_each_entry(c, &cdev->configs, list) {
 582                 /* ignore configs that won't work at this speed */
 583                 if (ssp) {
 584                         if (!c->superspeed_plus)
 585                                 continue;
 586                 } else if (ss) {
 587                         if (!c->superspeed)
 588                                 continue;
 589                 } else if (hs) {
 590                         if (!c->highspeed)
 591                                 continue;
 592                 } else {
 593                         if (!c->fullspeed)
 594                                 continue;
 595                 }
 596                 count++;
 597         }
 598         return count;
 599 }
 600
 601 /**
 602  * bos_desc() - prepares the BOS descriptor.
 603  * @cdev: pointer to usb_composite device to generate the bos
 604  *      descriptor for
 605  *
 606  * This function generates the BOS (Binary Device Object)
 607  * descriptor and its device capabilities descriptors. The BOS
 608  * descriptor should be supported by a SuperSpeed device.
 609  */
 610 static int bos_desc(struct usb_composite_dev *cdev)
 611 {
 612         struct usb_ext_cap_descriptor   *usb_ext;
 613         struct usb_ss_cap_descriptor    *ss_cap;
 614         struct usb_dcd_config_params    dcd_config_params;
 615         struct usb_bos_descriptor       *bos = cdev->req->buf;
 616
 617         bos->bLength = USB_DT_BOS_SIZE;
 618         bos->bDescriptorType = USB_DT_BOS;
 619
 620         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 621         bos->bNumDeviceCaps = 0;
 622
 623         /*
 624          * A SuperSpeed device shall include the USB2.0 extension descriptor
 625          * and shall support LPM when operating in USB2.0 HS mode.
 626          */
 627         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 628         bos->bNumDeviceCaps++;
 629         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 630         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 631         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 632         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 633         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | USB_BESL_SUPPORT);
 634
 635         /*
 636          * The Superspeed USB Capability descriptor shall be implemented by all
 637          * SuperSpeed devices.
 638          */
 639         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 640         bos->bNumDeviceCaps++;
 641         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 642         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 643         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 644         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 645         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 646         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 647                                 USB_FULL_SPEED_OPERATION |
 648                                 USB_HIGH_SPEED_OPERATION |
 649                                 USB_5GBPS_OPERATION);
 650         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 651
 652         /* Get Controller configuration */
 653         if (cdev->gadget->ops->get_config_params)
 654                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 655         else {
 656                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 657                 dcd_config_params.bU2DevExitLat =
 658                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 659         }
 660         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 661         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 662
 663         /* The SuperSpeedPlus USB Device Capability descriptor */
 664         if (gadget_is_superspeed_plus(cdev->gadget)) {
 665                 struct usb_ssp_cap_descriptor *ssp_cap;
 666
 667                 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 668                 bos->bNumDeviceCaps++;
 669
 670                 /*
 671                  * Report typical values.
 672                  */
 673
 674                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
 675                 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
 676                 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 677                 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 678                 ssp_cap->bReserved = 0;
 679                 ssp_cap->wReserved = 0;
 680
 681                 /* SSAC = 1 (2 attributes) */
 682                 ssp_cap->bmAttributes = cpu_to_le32(1);
 683
 684                 /* Min RX/TX Lane Count = 1 */
 685                 ssp_cap->wFunctionalitySupport =
 686                         cpu_to_le16((1 << 8) | (1 << 12));
 687
 688                 /*
 689                  * bmSublinkSpeedAttr[0]:
 690                  *   ST  = Symmetric, RX
 691                  *   LSE =  3 (Gbps)
 692                  *   LP  =  1 (SuperSpeedPlus)
 693                  *   LSM = 10 (10 Gbps)
 694                  */
 695                 ssp_cap->bmSublinkSpeedAttr[0] =
 696                         cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
 697                 /*
 698                  * bmSublinkSpeedAttr[1] =
 699                  *   ST  = Symmetric, TX
 700                  *   LSE =  3 (Gbps)
 701                  *   LP  =  1 (SuperSpeedPlus)
 702                  *   LSM = 10 (10 Gbps)
 703                  */
 704                 ssp_cap->bmSublinkSpeedAttr[1] =
 705                         cpu_to_le32((3 << 4) | (1 << 14) |
 706                                     (0xa << 16) | (1 << 7));
 707         }
 708
 709         return le16_to_cpu(bos->wTotalLength);
 710 }
 711
 712 static void device_qual(struct usb_composite_dev *cdev)
 713 {
 714         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 715
 716         qual->bLength = sizeof(*qual);
 717         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 718         /* POLICY: same bcdUSB and device type info at both speeds */
 719         qual->bcdUSB = cdev->desc.bcdUSB;
 720         qual->bDeviceClass = cdev->desc.bDeviceClass;
 721         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 722         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 723         /* ASSUME same EP0 fifo size at both speeds */
 724         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 725         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 726         qual->bRESERVED = 0;
 727 }
 728
 729 /*-------------------------------------------------------------------------*/
 730
 731 static void reset_config(struct usb_composite_dev *cdev)
 732 {
 733         struct usb_function             *f;
 734
 735         DBG(cdev, "reset config\n");
 736
 737         list_for_each_entry(f, &cdev->config->functions, list) {
 738                 if (f->disable)
 739                         f->disable(f);
 740
 741                 bitmap_zero(f->endpoints, 32);
 742         }
 743         cdev->config = NULL;
 744         cdev->delayed_status = 0;
 745 }
 746
 747 static int set_config(struct usb_composite_dev *cdev,
 748                 const struct usb_ctrlrequest *ctrl, unsigned number)
 749 {
 750         struct usb_gadget       *gadget = cdev->gadget;
 751         struct usb_configuration *c = NULL;
 752         int                     result = -EINVAL;
 753         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 754         int                     tmp;
 755
 756         if (number) {
 757                 list_for_each_entry(c, &cdev->configs, list) {
 758                         if (c->bConfigurationValue == number) {
 759                                 /*
 760                                  * We disable the FDs of the previous
 761                                  * configuration only if the new configuration
 762                                  * is a valid one
 763                                  */
 764                                 if (cdev->config)
 765                                         reset_config(cdev);
 766                                 result = 0;
 767                                 break;
 768                         }
 769                 }
 770                 if (result < 0)
 771                         goto done;
 772         } else { /* Zero configuration value - need to reset the config */
 773                 if (cdev->config)
 774                         reset_config(cdev);
 775                 result = 0;
 776         }
 777
 778         INFO(cdev, "%s config #%d: %s\n",
 779              usb_speed_string(gadget->speed),
 780              number, c ? c->label : "unconfigured");
 781
 782         if (!c)
 783                 goto done;
 784
 785         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 786         cdev->config = c;
 787
 788         /* Initialize all interfaces by setting them to altsetting zero. */
 789         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 790                 struct usb_function     *f = c->interface[tmp];
 791                 struct usb_descriptor_header **descriptors;
 792
 793                 if (!f)
 794                         break;
 795
 796                 /*
 797                  * Record which endpoints are used by the function. This is used
 798                  * to dispatch control requests targeted at that endpoint to the
 799                  * function's setup callback instead of the current
 800                  * configuration's setup callback.
 801                  */
 802                 descriptors = function_descriptors(f, gadget->speed);
 803
 804                 for (; *descriptors; ++descriptors) {
 805                         struct usb_endpoint_descriptor *ep;
 806                         int addr;
 807
 808                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 809                                 continue;
 810
 811                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 812                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 813                              |  (ep->bEndpointAddress & 0x0f);
 814                         set_bit(addr, f->endpoints);
 815                 }
 816
 817                 result = f->set_alt(f, tmp, 0);
 818                 if (result < 0) {
 819                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 820                                         tmp, f->name, f, result);
 821
 822                         reset_config(cdev);
 823                         goto done;
 824                 }
 825
 826                 if (result == USB_GADGET_DELAYED_STATUS) {
 827                         DBG(cdev,
 828                          "%s: interface %d (%s) requested delayed status\n",
 829                                         __func__, tmp, f->name);
 830                         cdev->delayed_status++;
 831                         DBG(cdev, "delayed_status count %d\n",
 832                                         cdev->delayed_status);
 833                 }
 834         }
 835
 836         /* when we return, be sure our power usage is valid */
 837         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 838 done:
 839         usb_gadget_vbus_draw(gadget, power);
 840         if (result >= 0 && cdev->delayed_status)
 841                 result = USB_GADGET_DELAYED_STATUS;
 842         return result;
 843 }
 844
 845 int usb_add_config_only(struct usb_composite_dev *cdev,
 846                 struct usb_configuration *config)
 847 {
 848         struct usb_configuration *c;
 849
 850         if (!config->bConfigurationValue)
 851                 return -EINVAL;
 852
 853         /* Prevent duplicate configuration identifiers */
 854         list_for_each_entry(c, &cdev->configs, list) {
 855                 if (c->bConfigurationValue == config->bConfigurationValue)
 856                         return -EBUSY;
 857         }
 858
 859         config->cdev = cdev;
 860         list_add_tail(&config->list, &cdev->configs);
 861
 862         INIT_LIST_HEAD(&config->functions);
 863         config->next_interface_id = 0;
 864         memset(config->interface, 0, sizeof(config->interface));
 865
 866         return 0;
 867 }
 868 EXPORT_SYMBOL_GPL(usb_add_config_only);
 869
 870 /**
 871  * usb_add_config() - add a configuration to a device.
 872  * @cdev: wraps the USB gadget
 873  * @config: the configuration, with bConfigurationValue assigned
 874  * @bind: the configuration's bind function
 875  * Context: single threaded during gadget setup
 876  *
 877  * One of the main tasks of a composite @bind() routine is to
 878  * add each of the configurations it supports, using this routine.
 879  *
 880  * This function returns the value of the configuration's @bind(), which
 881  * is zero for success else a negative errno value.  Binding configurations
 882  * assigns global resources including string IDs, and per-configuration
 883  * resources such as interface IDs and endpoints.
 884  */
 885 int usb_add_config(struct usb_composite_dev *cdev,
 886                 struct usb_configuration *config,
 887                 int (*bind)(struct usb_configuration *))
 888 {
 889         int                             status = -EINVAL;
 890
 891         if (!bind)
 892                 goto done;
 893
 894         DBG(cdev, "adding config #%u '%s'/%p\n",
 895                         config->bConfigurationValue,
 896                         config->label, config);
 897
 898         status = usb_add_config_only(cdev, config);
 899         if (status)
 900                 goto done;
 901
 902         status = bind(config);
 903         if (status < 0) {
 904                 while (!list_empty(&config->functions)) {
 905                         struct usb_function             *f;
 906
 907                         f = list_first_entry(&config->functions,
 908                                         struct usb_function, list);
 909                         list_del(&f->list);
 910                         if (f->unbind) {
 911                                 DBG(cdev, "unbind function '%s'/%p\n",
 912                                         f->name, f);
 913                                 f->unbind(config, f);
 914                                 /* may free memory for "f" */
 915                         }
 916                 }
 917                 list_del(&config->list);
 918                 config->cdev = NULL;
 919         } else {
 920                 unsigned        i;
 921
 922                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
 923                         config->bConfigurationValue, config,
 924                         config->superspeed_plus ? " superplus" : "",
 925                         config->superspeed ? " super" : "",
 926                         config->highspeed ? " high" : "",
 927                         config->fullspeed
 928                                 ? (gadget_is_dualspeed(cdev->gadget)
 929                                         ? " full"
 930                                         : " full/low")
 931                                 : "");
 932
 933                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 934                         struct usb_function     *f = config->interface[i];
 935
 936                         if (!f)
 937                                 continue;
 938                         DBG(cdev, "  interface %d = %s/%p\n",
 939                                 i, f->name, f);
 940                 }
 941         }
 942
 943         /* set_alt(), or next bind(), sets up ep->claimed as needed */
 944         usb_ep_autoconfig_reset(cdev->gadget);
 945
 946 done:
 947         if (status)
 948                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 949                                 config->bConfigurationValue, status);
 950         return status;
 951 }
 952 EXPORT_SYMBOL_GPL(usb_add_config);
 953
 954 static void remove_config(struct usb_composite_dev *cdev,
 955                               struct usb_configuration *config)
 956 {
 957         while (!list_empty(&config->functions)) {
 958                 struct usb_function             *f;
 959
 960                 f = list_first_entry(&config->functions,
 961                                 struct usb_function, list);
 962
 963                 usb_remove_function(config, f);
 964         }
 965         list_del(&config->list);
 966         if (config->unbind) {
 967                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 968                 config->unbind(config);
 969                         /* may free memory for "c" */
 970         }
 971 }
 972
 973 /**
 974  * usb_remove_config() - remove a configuration from a device.
 975  * @cdev: wraps the USB gadget
 976  * @config: the configuration
 977  *
 978  * Drivers must call usb_gadget_disconnect before calling this function
 979  * to disconnect the device from the host and make sure the host will not
 980  * try to enumerate the device while we are changing the config list.
 981  */
 982 void usb_remove_config(struct usb_composite_dev *cdev,
 983                       struct usb_configuration *config)
 984 {
 985         unsigned long flags;
 986
 987         spin_lock_irqsave(&cdev->lock, flags);
 988
 989         if (cdev->config == config)
 990                 reset_config(cdev);
 991
 992         spin_unlock_irqrestore(&cdev->lock, flags);
 993
 994         remove_config(cdev, config);
 995 }
 996
 997 /*-------------------------------------------------------------------------*/
 998
 999 /* We support strings in multiple languages ... string descriptor zero
1000  * says which languages are supported.  The typical case will be that
1001  * only one language (probably English) is used, with i18n handled on
1002  * the host side.
1003  */
1004
1005 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1006 {
1007         const struct usb_gadget_strings *s;
1008         __le16                          language;
1009         __le16                          *tmp;
1010
1011         while (*sp) {
1012                 s = *sp;
1013                 language = cpu_to_le16(s->language);
1014                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
1015                         if (*tmp == language)
1016                                 goto repeat;
1017                 }
1018                 *tmp++ = language;
1019 repeat:
1020                 sp++;
1021         }
1022 }
1023
1024 static int lookup_string(
1025         struct usb_gadget_strings       **sp,
1026         void                            *buf,
1027         u16                             language,
1028         int                             id
1029 )
1030 {
1031         struct usb_gadget_strings       *s;
1032         int                             value;
1033
1034         while (*sp) {
1035                 s = *sp++;
1036                 if (s->language != language)
1037                         continue;
1038                 value = usb_gadget_get_string(s, id, buf);
1039                 if (value > 0)
1040                         return value;
1041         }
1042         return -EINVAL;
1043 }
1044
1045 static int get_string(struct usb_composite_dev *cdev,
1046                 void *buf, u16 language, int id)
1047 {
1048         struct usb_composite_driver     *composite = cdev->driver;
1049         struct usb_gadget_string_container *uc;
1050         struct usb_configuration        *c;
1051         struct usb_function             *f;
1052         int                             len;
1053
1054         /* Yes, not only is USB's i18n support probably more than most
1055          * folk will ever care about ... also, it's all supported here.
1056          * (Except for UTF8 support for Unicode's "Astral Planes".)
1057          */
1058
1059         /* 0 == report all available language codes */
1060         if (id == 0) {
1061                 struct usb_string_descriptor    *s = buf;
1062                 struct usb_gadget_strings       **sp;
1063
1064                 memset(s, 0, 256);
1065                 s->bDescriptorType = USB_DT_STRING;
1066
1067                 sp = composite->strings;
1068                 if (sp)
1069                         collect_langs(sp, s->wData);
1070
1071                 list_for_each_entry(c, &cdev->configs, list) {
1072                         sp = c->strings;
1073                         if (sp)
1074                                 collect_langs(sp, s->wData);
1075
1076                         list_for_each_entry(f, &c->functions, list) {
1077                                 sp = f->strings;
1078                                 if (sp)
1079                                         collect_langs(sp, s->wData);
1080                         }
1081                 }
1082                 list_for_each_entry(uc, &cdev->gstrings, list) {
1083                         struct usb_gadget_strings **sp;
1084
1085                         sp = get_containers_gs(uc);
1086                         collect_langs(sp, s->wData);
1087                 }
1088
1089                 for (len = 0; len <= 126 && s->wData[len]; len++)
1090                         continue;
1091                 if (!len)
1092                         return -EINVAL;
1093
1094                 s->bLength = 2 * (len + 1);
1095                 return s->bLength;
1096         }
1097
1098         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1099                 struct usb_os_string *b = buf;
1100                 b->bLength = sizeof(*b);
1101                 b->bDescriptorType = USB_DT_STRING;
1102                 compiletime_assert(
1103                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1104                         "qwSignature size must be equal to qw_sign");
1105                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1106                 b->bMS_VendorCode = cdev->b_vendor_code;
1107                 b->bPad = 0;
1108                 return sizeof(*b);
1109         }
1110
1111         list_for_each_entry(uc, &cdev->gstrings, list) {
1112                 struct usb_gadget_strings **sp;
1113
1114                 sp = get_containers_gs(uc);
1115                 len = lookup_string(sp, buf, language, id);
1116                 if (len > 0)
1117                         return len;
1118         }
1119
1120         /* String IDs are device-scoped, so we look up each string
1121          * table we're told about.  These lookups are infrequent;
1122          * simpler-is-better here.
1123          */
1124         if (composite->strings) {
1125                 len = lookup_string(composite->strings, buf, language, id);
1126                 if (len > 0)
1127                         return len;
1128         }
1129         list_for_each_entry(c, &cdev->configs, list) {
1130                 if (c->strings) {
1131                         len = lookup_string(c->strings, buf, language, id);
1132                         if (len > 0)
1133                                 return len;
1134                 }
1135                 list_for_each_entry(f, &c->functions, list) {
1136                         if (!f->strings)
1137                                 continue;
1138                         len = lookup_string(f->strings, buf, language, id);
1139                         if (len > 0)
1140                                 return len;
1141                 }
1142         }
1143         return -EINVAL;
1144 }
1145
1146 /**
1147  * usb_string_id() - allocate an unused string ID
1148  * @cdev: the device whose string descriptor IDs are being allocated
1149  * Context: single threaded during gadget setup
1150  *
1151  * @usb_string_id() is called from bind() callbacks to allocate
1152  * string IDs.  Drivers for functions, configurations, or gadgets will
1153  * then store that ID in the appropriate descriptors and string table.
1154  *
1155  * All string identifier should be allocated using this,
1156  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1157  * that for example different functions don't wrongly assign different
1158  * meanings to the same identifier.
1159  */
1160 int usb_string_id(struct usb_composite_dev *cdev)
1161 {
1162         if (cdev->next_string_id < 254) {
1163                 /* string id 0 is reserved by USB spec for list of
1164                  * supported languages */
1165                 /* 255 reserved as well? -- mina86 */
1166                 cdev->next_string_id++;
1167                 return cdev->next_string_id;
1168         }
1169         return -ENODEV;
1170 }
1171 EXPORT_SYMBOL_GPL(usb_string_id);
1172
1173 /**
1174  * usb_string_ids() - allocate unused string IDs in batch
1175  * @cdev: the device whose string descriptor IDs are being allocated
1176  * @str: an array of usb_string objects to assign numbers to
1177  * Context: single threaded during gadget setup
1178  *
1179  * @usb_string_ids() is called from bind() callbacks to allocate
1180  * string IDs.  Drivers for functions, configurations, or gadgets will
1181  * then copy IDs from the string table to the appropriate descriptors
1182  * and string table for other languages.
1183  *
1184  * All string identifier should be allocated using this,
1185  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1186  * example different functions don't wrongly assign different meanings
1187  * to the same identifier.
1188  */
1189 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1190 {
1191         int next = cdev->next_string_id;
1192
1193         for (; str->s; ++str) {
1194                 if (unlikely(next >= 254))
1195                         return -ENODEV;
1196                 str->id = ++next;
1197         }
1198
1199         cdev->next_string_id = next;
1200
1201         return 0;
1202 }
1203 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1204
1205 static struct usb_gadget_string_container *copy_gadget_strings(
1206                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1207                 unsigned n_strings)
1208 {
1209         struct usb_gadget_string_container *uc;
1210         struct usb_gadget_strings **gs_array;
1211         struct usb_gadget_strings *gs;
1212         struct usb_string *s;
1213         unsigned mem;
1214         unsigned n_gs;
1215         unsigned n_s;
1216         void *stash;
1217
1218         mem = sizeof(*uc);
1219         mem += sizeof(void *) * (n_gstrings + 1);
1220         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1221         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1222         uc = kmalloc(mem, GFP_KERNEL);
1223         if (!uc)
1224                 return ERR_PTR(-ENOMEM);
1225         gs_array = get_containers_gs(uc);
1226         stash = uc->stash;
1227         stash += sizeof(void *) * (n_gstrings + 1);
1228         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1229                 struct usb_string *org_s;
1230
1231                 gs_array[n_gs] = stash;
1232                 gs = gs_array[n_gs];
1233                 stash += sizeof(struct usb_gadget_strings);
1234                 gs->language = sp[n_gs]->language;
1235                 gs->strings = stash;
1236                 org_s = sp[n_gs]->strings;
1237
1238                 for (n_s = 0; n_s < n_strings; n_s++) {
1239                         s = stash;
1240                         stash += sizeof(struct usb_string);
1241                         if (org_s->s)
1242                                 s->s = org_s->s;
1243                         else
1244                                 s->s = "";
1245                         org_s++;
1246                 }
1247                 s = stash;
1248                 s->s = NULL;
1249                 stash += sizeof(struct usb_string);
1250
1251         }
1252         gs_array[n_gs] = NULL;
1253         return uc;
1254 }
1255
1256 /**
1257  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1258  * @cdev: the device whose string descriptor IDs are being allocated
1259  * and attached.
1260  * @sp: an array of usb_gadget_strings to attach.
1261  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1262  *
1263  * This function will create a deep copy of usb_gadget_strings and usb_string
1264  * and attach it to the cdev. The actual string (usb_string.s) will not be
1265  * copied but only a referenced will be made. The struct usb_gadget_strings
1266  * array may contain multiple languages and should be NULL terminated.
1267  * The ->language pointer of each struct usb_gadget_strings has to contain the
1268  * same amount of entries.
1269  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1270  * usb_string entry of es-ES contains the translation of the first usb_string
1271  * entry of en-US. Therefore both entries become the same id assign.
1272  */
1273 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1274                 struct usb_gadget_strings **sp, unsigned n_strings)
1275 {
1276         struct usb_gadget_string_container *uc;
1277         struct usb_gadget_strings **n_gs;
1278         unsigned n_gstrings = 0;
1279         unsigned i;
1280         int ret;
1281
1282         for (i = 0; sp[i]; i++)
1283                 n_gstrings++;
1284
1285         if (!n_gstrings)
1286                 return ERR_PTR(-EINVAL);
1287
1288         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1289         if (IS_ERR(uc))
1290                 return ERR_CAST(uc);
1291
1292         n_gs = get_containers_gs(uc);
1293         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1294         if (ret)
1295                 goto err;
1296
1297         for (i = 1; i < n_gstrings; i++) {
1298                 struct usb_string *m_s;
1299                 struct usb_string *s;
1300                 unsigned n;
1301
1302                 m_s = n_gs[0]->strings;
1303                 s = n_gs[i]->strings;
1304                 for (n = 0; n < n_strings; n++) {
1305                         s->id = m_s->id;
1306                         s++;
1307                         m_s++;
1308                 }
1309         }
1310         list_add_tail(&uc->list, &cdev->gstrings);
1311         return n_gs[0]->strings;
1312 err:
1313         kfree(uc);
1314         return ERR_PTR(ret);
1315 }
1316 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1317
1318 /**
1319  * usb_string_ids_n() - allocate unused string IDs in batch
1320  * @c: the device whose string descriptor IDs are being allocated
1321  * @n: number of string IDs to allocate
1322  * Context: single threaded during gadget setup
1323  *
1324  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1325  * valid IDs.  At least provided that @n is non-zero because if it
1326  * is, returns last requested ID which is now very useful information.
1327  *
1328  * @usb_string_ids_n() is called from bind() callbacks to allocate
1329  * string IDs.  Drivers for functions, configurations, or gadgets will
1330  * then store that ID in the appropriate descriptors and string table.
1331  *
1332  * All string identifier should be allocated using this,
1333  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1334  * example different functions don't wrongly assign different meanings
1335  * to the same identifier.
1336  */
1337 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1338 {
1339         unsigned next = c->next_string_id;
1340         if (unlikely(n > 254 || (unsigned)next + n > 254))
1341                 return -ENODEV;
1342         c->next_string_id += n;
1343         return next + 1;
1344 }
1345 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1346
1347 /*-------------------------------------------------------------------------*/
1348
1349 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1350 {
1351         struct usb_composite_dev *cdev;
1352
1353         if (req->status || req->actual != req->length)
1354                 DBG((struct usb_composite_dev *) ep->driver_data,
1355                                 "setup complete --> %d, %d/%d\n",
1356                                 req->status, req->actual, req->length);
1357
1358         /*
1359          * REVIST The same ep0 requests are shared with function drivers
1360          * so they don't have to maintain the same ->complete() stubs.
1361          *
1362          * Because of that, we need to check for the validity of ->context
1363          * here, even though we know we've set it to something useful.
1364          */
1365         if (!req->context)
1366                 return;
1367
1368         cdev = req->context;
1369
1370         if (cdev->req == req)
1371                 cdev->setup_pending = false;
1372         else if (cdev->os_desc_req == req)
1373                 cdev->os_desc_pending = false;
1374         else
1375                 WARN(1, "unknown request %p\n", req);
1376 }
1377
1378 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1379                 struct usb_request *req, gfp_t gfp_flags)
1380 {
1381         int ret;
1382
1383         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1384         if (ret == 0) {
1385                 if (cdev->req == req)
1386                         cdev->setup_pending = true;
1387                 else if (cdev->os_desc_req == req)
1388                         cdev->os_desc_pending = true;
1389                 else
1390                         WARN(1, "unknown request %p\n", req);
1391         }
1392
1393         return ret;
1394 }
1395
1396 static int count_ext_compat(struct usb_configuration *c)
1397 {
1398         int i, res;
1399
1400         res = 0;
1401         for (i = 0; i < c->next_interface_id; ++i) {
1402                 struct usb_function *f;
1403                 int j;
1404
1405                 f = c->interface[i];
1406                 for (j = 0; j < f->os_desc_n; ++j) {
1407                         struct usb_os_desc *d;
1408
1409                         if (i != f->os_desc_table[j].if_id)
1410                                 continue;
1411                         d = f->os_desc_table[j].os_desc;
1412                         if (d && d->ext_compat_id)
1413                                 ++res;
1414                 }
1415         }
1416         BUG_ON(res > 255);
1417         return res;
1418 }
1419
1420 static void fill_ext_compat(struct usb_configuration *c, u8 *buf)
1421 {
1422         int i, count;
1423
1424         count = 16;
1425         for (i = 0; i < c->next_interface_id; ++i) {
1426                 struct usb_function *f;
1427                 int j;
1428
1429                 f = c->interface[i];
1430                 for (j = 0; j < f->os_desc_n; ++j) {
1431                         struct usb_os_desc *d;
1432
1433                         if (i != f->os_desc_table[j].if_id)
1434                                 continue;
1435                         d = f->os_desc_table[j].os_desc;
1436                         if (d && d->ext_compat_id) {
1437                                 *buf++ = i;
1438                                 *buf++ = 0x01;
1439                                 memcpy(buf, d->ext_compat_id, 16);
1440                                 buf += 22;
1441                         } else {
1442                                 ++buf;
1443                                 *buf = 0x01;
1444                                 buf += 23;
1445                         }
1446                         count += 24;
1447                         if (count >= 4096)
1448                                 return;
1449                 }
1450         }
1451 }
1452
1453 static int count_ext_prop(struct usb_configuration *c, int interface)
1454 {
1455         struct usb_function *f;
1456         int j;
1457
1458         f = c->interface[interface];
1459         for (j = 0; j < f->os_desc_n; ++j) {
1460                 struct usb_os_desc *d;
1461
1462                 if (interface != f->os_desc_table[j].if_id)
1463                         continue;
1464                 d = f->os_desc_table[j].os_desc;
1465                 if (d && d->ext_compat_id)
1466                         return d->ext_prop_count;
1467         }
1468         return 0;
1469 }
1470
1471 static int len_ext_prop(struct usb_configuration *c, int interface)
1472 {
1473         struct usb_function *f;
1474         struct usb_os_desc *d;
1475         int j, res;
1476
1477         res = 10; /* header length */
1478         f = c->interface[interface];
1479         for (j = 0; j < f->os_desc_n; ++j) {
1480                 if (interface != f->os_desc_table[j].if_id)
1481                         continue;
1482                 d = f->os_desc_table[j].os_desc;
1483                 if (d)
1484                         return min(res + d->ext_prop_len, 4096);
1485         }
1486         return res;
1487 }
1488
1489 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1490 {
1491         struct usb_function *f;
1492         struct usb_os_desc *d;
1493         struct usb_os_desc_ext_prop *ext_prop;
1494         int j, count, n, ret;
1495         u8 *start = buf;
1496
1497         f = c->interface[interface];
1498         for (j = 0; j < f->os_desc_n; ++j) {
1499                 if (interface != f->os_desc_table[j].if_id)
1500                         continue;
1501                 d = f->os_desc_table[j].os_desc;
1502                 if (d)
1503                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1504                                 /* 4kB minus header length */
1505                                 n = buf - start;
1506                                 if (n >= 4086)
1507                                         return 0;
1508
1509                                 count = ext_prop->data_len +
1510                                         ext_prop->name_len + 14;
1511                                 if (count > 4086 - n)
1512                                         return -EINVAL;
1513                                 usb_ext_prop_put_size(buf, count);
1514                                 usb_ext_prop_put_type(buf, ext_prop->type);
1515                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1516                                                             ext_prop->name_len);
1517                                 if (ret < 0)
1518                                         return ret;
1519                                 switch (ext_prop->type) {
1520                                 case USB_EXT_PROP_UNICODE:
1521                                 case USB_EXT_PROP_UNICODE_ENV:
1522                                 case USB_EXT_PROP_UNICODE_LINK:
1523                                         usb_ext_prop_put_unicode(buf, ret,
1524                                                          ext_prop->data,
1525                                                          ext_prop->data_len);
1526                                         break;
1527                                 case USB_EXT_PROP_BINARY:
1528                                         usb_ext_prop_put_binary(buf, ret,
1529                                                         ext_prop->data,
1530                                                         ext_prop->data_len);
1531                                         break;
1532                                 case USB_EXT_PROP_LE32:
1533                                         /* not implemented */
1534                                 case USB_EXT_PROP_BE32:
1535                                         /* not implemented */
1536                                 default:
1537                                         return -EINVAL;
1538                                 }
1539                                 buf += count;
1540                         }
1541         }
1542
1543         return 0;
1544 }
1545
1546 /*
1547  * The setup() callback implements all the ep0 functionality that's
1548  * not handled lower down, in hardware or the hardware driver(like
1549  * device and endpoint feature flags, and their status).  It's all
1550  * housekeeping for the gadget function we're implementing.  Most of
1551  * the work is in config and function specific setup.
1552  */
1553 int
1554 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1555 {
1556         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1557         struct usb_request              *req = cdev->req;
1558         int                             value = -EOPNOTSUPP;
1559         int                             status = 0;
1560         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1561         u8                              intf = w_index & 0xFF;
1562         u16                             w_value = le16_to_cpu(ctrl->wValue);
1563         u16                             w_length = le16_to_cpu(ctrl->wLength);
1564         struct usb_function             *f = NULL;
1565         u8                              endp;
1566
1567         /* partial re-init of the response message; the function or the
1568          * gadget might need to intercept e.g. a control-OUT completion
1569          * when we delegate to it.
1570          */
1571         req->zero = 0;
1572         req->context = cdev;
1573         req->complete = composite_setup_complete;
1574         req->length = 0;
1575         gadget->ep0->driver_data = cdev;
1576
1577         /*
1578          * Don't let non-standard requests match any of the cases below
1579          * by accident.
1580          */
1581         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1582                 goto unknown;
1583
1584         switch (ctrl->bRequest) {
1585
1586         /* we handle all standard USB descriptors */
1587         case USB_REQ_GET_DESCRIPTOR:
1588                 if (ctrl->bRequestType != USB_DIR_IN)
1589                         goto unknown;
1590                 switch (w_value >> 8) {
1591
1592                 case USB_DT_DEVICE:
1593                         cdev->desc.bNumConfigurations =
1594                                 count_configs(cdev, USB_DT_DEVICE);
1595                         cdev->desc.bMaxPacketSize0 =
1596                                 cdev->gadget->ep0->maxpacket;
1597                         if (gadget_is_superspeed(gadget)) {
1598                                 if (gadget->speed >= USB_SPEED_SUPER) {
1599                                         cdev->desc.bcdUSB = cpu_to_le16(0x0310);
1600                                         cdev->desc.bMaxPacketSize0 = 9;
1601                                 } else {
1602                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1603                                 }
1604                         } else {
1605                                 cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1606                         }
1607
1608                         value = min(w_length, (u16) sizeof cdev->desc);
1609                         memcpy(req->buf, &cdev->desc, value);
1610                         break;
1611                 case USB_DT_DEVICE_QUALIFIER:
1612                         if (!gadget_is_dualspeed(gadget) ||
1613                             gadget->speed >= USB_SPEED_SUPER)
1614                                 break;
1615                         device_qual(cdev);
1616                         value = min_t(int, w_length,
1617                                 sizeof(struct usb_qualifier_descriptor));
1618                         break;
1619                 case USB_DT_OTHER_SPEED_CONFIG:
1620                         if (!gadget_is_dualspeed(gadget) ||
1621                             gadget->speed >= USB_SPEED_SUPER)
1622                                 break;
1623                         /* FALLTHROUGH */
1624                 case USB_DT_CONFIG:
1625                         value = config_desc(cdev, w_value);
1626                         if (value >= 0)
1627                                 value = min(w_length, (u16) value);
1628                         break;
1629                 case USB_DT_STRING:
1630                         value = get_string(cdev, req->buf,
1631                                         w_index, w_value & 0xff);
1632                         if (value >= 0)
1633                                 value = min(w_length, (u16) value);
1634                         break;
1635                 case USB_DT_BOS:
1636                         if (gadget_is_superspeed(gadget)) {
1637                                 value = bos_desc(cdev);
1638                                 value = min(w_length, (u16) value);
1639                         }
1640                         break;
1641                 case USB_DT_OTG:
1642                         if (gadget_is_otg(gadget)) {
1643                                 struct usb_configuration *config;
1644                                 int otg_desc_len = 0;
1645
1646                                 if (cdev->config)
1647                                         config = cdev->config;
1648                                 else
1649                                         config = list_first_entry(
1650                                                         &cdev->configs,
1651                                                 struct usb_configuration, list);
1652                                 if (!config)
1653                                         goto done;
1654
1655                                 if (gadget->otg_caps &&
1656                                         (gadget->otg_caps->otg_rev >= 0x0200))
1657                                         otg_desc_len += sizeof(
1658                                                 struct usb_otg20_descriptor);
1659                                 else
1660                                         otg_desc_len += sizeof(
1661                                                 struct usb_otg_descriptor);
1662
1663                                 value = min_t(int, w_length, otg_desc_len);
1664                                 memcpy(req->buf, config->descriptors[0], value);
1665                         }
1666                         break;
1667                 }
1668                 break;
1669
1670         /* any number of configs can work */
1671         case USB_REQ_SET_CONFIGURATION:
1672                 if (ctrl->bRequestType != 0)
1673                         goto unknown;
1674                 if (gadget_is_otg(gadget)) {
1675                         if (gadget->a_hnp_support)
1676                                 DBG(cdev, "HNP available\n");
1677                         else if (gadget->a_alt_hnp_support)
1678                                 DBG(cdev, "HNP on another port\n");
1679                         else
1680                                 VDBG(cdev, "HNP inactive\n");
1681                 }
1682                 spin_lock(&cdev->lock);
1683                 value = set_config(cdev, ctrl, w_value);
1684                 spin_unlock(&cdev->lock);
1685                 break;
1686         case USB_REQ_GET_CONFIGURATION:
1687                 if (ctrl->bRequestType != USB_DIR_IN)
1688                         goto unknown;
1689                 if (cdev->config)
1690                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1691                 else
1692                         *(u8 *)req->buf = 0;
1693                 value = min(w_length, (u16) 1);
1694                 break;
1695
1696         /* function drivers must handle get/set altsetting */
1697         case USB_REQ_SET_INTERFACE:
1698                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1699                         goto unknown;
1700                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1701                         break;
1702                 f = cdev->config->interface[intf];
1703                 if (!f)
1704                         break;
1705
1706                 /*
1707                  * If there's no get_alt() method, we know only altsetting zero
1708                  * works. There is no need to check if set_alt() is not NULL
1709                  * as we check this in usb_add_function().
1710                  */
1711                 if (w_value && !f->get_alt)
1712                         break;
1713                 value = f->set_alt(f, w_index, w_value);
1714                 if (value == USB_GADGET_DELAYED_STATUS) {
1715                         DBG(cdev,
1716                          "%s: interface %d (%s) requested delayed status\n",
1717                                         __func__, intf, f->name);
1718                         cdev->delayed_status++;
1719                         DBG(cdev, "delayed_status count %d\n",
1720                                         cdev->delayed_status);
1721                 }
1722                 break;
1723         case USB_REQ_GET_INTERFACE:
1724                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1725                         goto unknown;
1726                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1727                         break;
1728                 f = cdev->config->interface[intf];
1729                 if (!f)
1730                         break;
1731                 /* lots of interfaces only need altsetting zero... */
1732                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1733                 if (value < 0)
1734                         break;
1735                 *((u8 *)req->buf) = value;
1736                 value = min(w_length, (u16) 1);
1737                 break;
1738         case USB_REQ_GET_STATUS:
1739                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1740                                                 (w_index == OTG_STS_SELECTOR)) {
1741                         if (ctrl->bRequestType != (USB_DIR_IN |
1742                                                         USB_RECIP_DEVICE))
1743                                 goto unknown;
1744                         *((u8 *)req->buf) = gadget->host_request_flag;
1745                         value = 1;
1746                         break;
1747                 }
1748
1749                 /*
1750                  * USB 3.0 additions:
1751                  * Function driver should handle get_status request. If such cb
1752                  * wasn't supplied we respond with default value = 0
1753                  * Note: function driver should supply such cb only for the
1754                  * first interface of the function
1755                  */
1756                 if (!gadget_is_superspeed(gadget))
1757                         goto unknown;
1758                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1759                         goto unknown;
1760                 value = 2;      /* This is the length of the get_status reply */
1761                 put_unaligned_le16(0, req->buf);
1762                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1763                         break;
1764                 f = cdev->config->interface[intf];
1765                 if (!f)
1766                         break;
1767                 status = f->get_status ? f->get_status(f) : 0;
1768                 if (status < 0)
1769                         break;
1770                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1771                 break;
1772         /*
1773          * Function drivers should handle SetFeature/ClearFeature
1774          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1775          * only for the first interface of the function
1776          */
1777         case USB_REQ_CLEAR_FEATURE:
1778         case USB_REQ_SET_FEATURE:
1779                 if (!gadget_is_superspeed(gadget))
1780                         goto unknown;
1781                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1782                         goto unknown;
1783                 switch (w_value) {
1784                 case USB_INTRF_FUNC_SUSPEND:
1785                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1786                                 break;
1787                         f = cdev->config->interface[intf];
1788                         if (!f)
1789                                 break;
1790                         value = 0;
1791                         if (f->func_suspend)
1792                                 value = f->func_suspend(f, w_index >> 8);
1793                         if (value < 0) {
1794                                 ERROR(cdev,
1795                                       "func_suspend() returned error %d\n",
1796                                       value);
1797                                 value = 0;
1798                         }
1799                         break;
1800                 }
1801                 break;
1802         default:
1803 unknown:
1804                 /*
1805                  * OS descriptors handling
1806                  */
1807                 if (cdev->use_os_string && cdev->os_desc_config &&
1808                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1809                     ctrl->bRequest == cdev->b_vendor_code) {
1810                         struct usb_request              *req;
1811                         struct usb_configuration        *os_desc_cfg;
1812                         u8                              *buf;
1813                         int                             interface;
1814                         int                             count = 0;
1815
1816                         req = cdev->os_desc_req;
1817                         req->context = cdev;
1818                         req->complete = composite_setup_complete;
1819                         buf = req->buf;
1820                         os_desc_cfg = cdev->os_desc_config;
1821                         memset(buf, 0, w_length);
1822                         buf[5] = 0x01;
1823                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1824                         case USB_RECIP_DEVICE:
1825                                 if (w_index != 0x4 || (w_value >> 8))
1826                                         break;
1827                                 buf[6] = w_index;
1828                                 if (w_length == 0x10) {
1829                                         /* Number of ext compat interfaces */
1830                                         count = count_ext_compat(os_desc_cfg);
1831                                         buf[8] = count;
1832                                         count *= 24; /* 24 B/ext compat desc */
1833                                         count += 16; /* header */
1834                                         put_unaligned_le32(count, buf);
1835                                         value = w_length;
1836                                 } else {
1837                                         /* "extended compatibility ID"s */
1838                                         count = count_ext_compat(os_desc_cfg);
1839                                         buf[8] = count;
1840                                         count *= 24; /* 24 B/ext compat desc */
1841                                         count += 16; /* header */
1842                                         put_unaligned_le32(count, buf);
1843                                         buf += 16;
1844                                         fill_ext_compat(os_desc_cfg, buf);
1845                                         value = w_length;
1846                                 }
1847                                 break;
1848                         case USB_RECIP_INTERFACE:
1849                                 if (w_index != 0x5 || (w_value >> 8))
1850                                         break;
1851                                 interface = w_value & 0xFF;
1852                                 buf[6] = w_index;
1853                                 if (w_length == 0x0A) {
1854                                         count = count_ext_prop(os_desc_cfg,
1855                                                 interface);
1856                                         put_unaligned_le16(count, buf + 8);
1857                                         count = len_ext_prop(os_desc_cfg,
1858                                                 interface);
1859                                         put_unaligned_le32(count, buf);
1860
1861                                         value = w_length;
1862                                 } else {
1863                                         count = count_ext_prop(os_desc_cfg,
1864                                                 interface);
1865                                         put_unaligned_le16(count, buf + 8);
1866                                         count = len_ext_prop(os_desc_cfg,
1867                                                 interface);
1868                                         put_unaligned_le32(count, buf);
1869                                         buf += 10;
1870                                         value = fill_ext_prop(os_desc_cfg,
1871                                                               interface, buf);
1872                                         if (value < 0)
1873                                                 return value;
1874
1875                                         value = w_length;
1876                                 }
1877                                 break;
1878                         }
1879
1880                         if (value >= 0) {
1881                                 req->length = value;
1882                                 req->context = cdev;
1883                                 req->zero = value < w_length;
1884                                 value = composite_ep0_queue(cdev, req,
1885                                                             GFP_ATOMIC);
1886                                 if (value < 0) {
1887                                         DBG(cdev, "ep_queue --> %d\n", value);
1888                                         req->status = 0;
1889                                         composite_setup_complete(gadget->ep0,
1890                                                                  req);
1891                                 }
1892                         }
1893                         return value;
1894                 }
1895
1896                 VDBG(cdev,
1897                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1898                         ctrl->bRequestType, ctrl->bRequest,
1899                         w_value, w_index, w_length);
1900
1901                 /* functions always handle their interfaces and endpoints...
1902                  * punt other recipients (other, WUSB, ...) to the current
1903                  * configuration code.
1904                  */
1905                 if (cdev->config) {
1906                         list_for_each_entry(f, &cdev->config->functions, list)
1907                                 if (f->req_match &&
1908                                     f->req_match(f, ctrl, false))
1909                                         goto try_fun_setup;
1910                 } else {
1911                         struct usb_configuration *c;
1912                         list_for_each_entry(c, &cdev->configs, list)
1913                                 list_for_each_entry(f, &c->functions, list)
1914                                         if (f->req_match &&
1915                                             f->req_match(f, ctrl, true))
1916                                                 goto try_fun_setup;
1917                 }
1918                 f = NULL;
1919
1920                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1921                 case USB_RECIP_INTERFACE:
1922                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1923                                 break;
1924                         f = cdev->config->interface[intf];
1925                         break;
1926
1927                 case USB_RECIP_ENDPOINT:
1928                         if (!cdev->config)
1929                                 break;
1930                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1931                         list_for_each_entry(f, &cdev->config->functions, list) {
1932                                 if (test_bit(endp, f->endpoints))
1933                                         break;
1934                         }
1935                         if (&f->list == &cdev->config->functions)
1936                                 f = NULL;
1937                         break;
1938                 }
1939 try_fun_setup:
1940                 if (f && f->setup)
1941                         value = f->setup(f, ctrl);
1942                 else {
1943                         struct usb_configuration        *c;
1944
1945                         c = cdev->config;
1946                         if (!c)
1947                                 goto done;
1948
1949                         /* try current config's setup */
1950                         if (c->setup) {
1951                                 value = c->setup(c, ctrl);
1952                                 goto done;
1953                         }
1954
1955                         /* try the only function in the current config */
1956                         if (!list_is_singular(&c->functions))
1957                                 goto done;
1958                         f = list_first_entry(&c->functions, struct usb_function,
1959                                              list);
1960                         if (f->setup)
1961                                 value = f->setup(f, ctrl);
1962                 }
1963
1964                 goto done;
1965         }
1966
1967         /* respond with data transfer before status phase? */
1968         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1969                 req->length = value;
1970                 req->context = cdev;
1971                 req->zero = value < w_length;
1972                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1973                 if (value < 0) {
1974                         DBG(cdev, "ep_queue --> %d\n", value);
1975                         req->status = 0;
1976                         composite_setup_complete(gadget->ep0, req);
1977                 }
1978         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1979                 WARN(cdev,
1980                         "%s: Delayed status not supported for w_length != 0",
1981                         __func__);
1982         }
1983
1984 done:
1985         /* device either stalls (value < 0) or reports success */
1986         return value;
1987 }
1988
1989 void composite_disconnect(struct usb_gadget *gadget)
1990 {
1991         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1992         unsigned long                   flags;
1993
1994         /* REVISIT:  should we have config and device level
1995          * disconnect callbacks?
1996          */
1997         spin_lock_irqsave(&cdev->lock, flags);
1998         if (cdev->config)
1999                 reset_config(cdev);
2000         if (cdev->driver->disconnect)
2001                 cdev->driver->disconnect(cdev);
2002         spin_unlock_irqrestore(&cdev->lock, flags);
2003 }
2004
2005 /*-------------------------------------------------------------------------*/
2006
2007 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2008                               char *buf)
2009 {
2010         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2011         struct usb_composite_dev *cdev = get_gadget_data(gadget);
2012
2013         return sprintf(buf, "%d\n", cdev->suspended);
2014 }
2015 static DEVICE_ATTR_RO(suspended);
2016
2017 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2018 {
2019         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2020
2021         /* composite_disconnect() must already have been called
2022          * by the underlying peripheral controller driver!
2023          * so there's no i/o concurrency that could affect the
2024          * state protected by cdev->lock.
2025          */
2026         WARN_ON(cdev->config);
2027
2028         while (!list_empty(&cdev->configs)) {
2029                 struct usb_configuration        *c;
2030                 c = list_first_entry(&cdev->configs,
2031                                 struct usb_configuration, list);
2032                 remove_config(cdev, c);
2033         }
2034         if (cdev->driver->unbind && unbind_driver)
2035                 cdev->driver->unbind(cdev);
2036
2037         composite_dev_cleanup(cdev);
2038
2039         kfree(cdev->def_manufacturer);
2040         kfree(cdev);
2041         set_gadget_data(gadget, NULL);
2042 }
2043
2044 static void composite_unbind(struct usb_gadget *gadget)
2045 {
2046         __composite_unbind(gadget, true);
2047 }
2048
2049 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2050                 const struct usb_device_descriptor *old)
2051 {
2052         __le16 idVendor;
2053         __le16 idProduct;
2054         __le16 bcdDevice;
2055         u8 iSerialNumber;
2056         u8 iManufacturer;
2057         u8 iProduct;
2058
2059         /*
2060          * these variables may have been set in
2061          * usb_composite_overwrite_options()
2062          */
2063         idVendor = new->idVendor;
2064         idProduct = new->idProduct;
2065         bcdDevice = new->bcdDevice;
2066         iSerialNumber = new->iSerialNumber;
2067         iManufacturer = new->iManufacturer;
2068         iProduct = new->iProduct;
2069
2070         *new = *old;
2071         if (idVendor)
2072                 new->idVendor = idVendor;
2073         if (idProduct)
2074                 new->idProduct = idProduct;
2075         if (bcdDevice)
2076                 new->bcdDevice = bcdDevice;
2077         else
2078                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2079         if (iSerialNumber)
2080                 new->iSerialNumber = iSerialNumber;
2081         if (iManufacturer)
2082                 new->iManufacturer = iManufacturer;
2083         if (iProduct)
2084                 new->iProduct = iProduct;
2085 }
2086
2087 int composite_dev_prepare(struct usb_composite_driver *composite,
2088                 struct usb_composite_dev *cdev)
2089 {
2090         struct usb_gadget *gadget = cdev->gadget;
2091         int ret = -ENOMEM;
2092
2093         /* preallocate control response and buffer */
2094         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2095         if (!cdev->req)
2096                 return -ENOMEM;
2097
2098         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2099         if (!cdev->req->buf)
2100                 goto fail;
2101
2102         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2103         if (ret)
2104                 goto fail_dev;
2105
2106         cdev->req->complete = composite_setup_complete;
2107         cdev->req->context = cdev;
2108         gadget->ep0->driver_data = cdev;
2109
2110         cdev->driver = composite;
2111
2112         /*
2113          * As per USB compliance update, a device that is actively drawing
2114          * more than 100mA from USB must report itself as bus-powered in
2115          * the GetStatus(DEVICE) call.
2116          */
2117         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2118                 usb_gadget_set_selfpowered(gadget);
2119
2120         /* interface and string IDs start at zero via kzalloc.
2121          * we force endpoints to start unassigned; few controller
2122          * drivers will zero ep->driver_data.
2123          */
2124         usb_ep_autoconfig_reset(gadget);
2125         return 0;
2126 fail_dev:
2127         kfree(cdev->req->buf);
2128 fail:
2129         usb_ep_free_request(gadget->ep0, cdev->req);
2130         cdev->req = NULL;
2131         return ret;
2132 }
2133
2134 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2135                                   struct usb_ep *ep0)
2136 {
2137         int ret = 0;
2138
2139         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2140         if (!cdev->os_desc_req) {
2141                 ret = -ENOMEM;
2142                 goto end;
2143         }
2144
2145         /* OS feature descriptor length <= 4kB */
2146         cdev->os_desc_req->buf = kmalloc(4096, GFP_KERNEL);
2147         if (!cdev->os_desc_req->buf) {
2148                 ret = -ENOMEM;
2149                 usb_ep_free_request(ep0, cdev->os_desc_req);
2150                 goto end;
2151         }
2152         cdev->os_desc_req->context = cdev;
2153         cdev->os_desc_req->complete = composite_setup_complete;
2154 end:
2155         return ret;
2156 }
2157
2158 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2159 {
2160         struct usb_gadget_string_container *uc, *tmp;
2161
2162         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2163                 list_del(&uc->list);
2164                 kfree(uc);
2165         }
2166         if (cdev->os_desc_req) {
2167                 if (cdev->os_desc_pending)
2168                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2169
2170                 kfree(cdev->os_desc_req->buf);
2171                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2172         }
2173         if (cdev->req) {
2174                 if (cdev->setup_pending)
2175                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2176
2177                 kfree(cdev->req->buf);
2178                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2179         }
2180         cdev->next_string_id = 0;
2181         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2182 }
2183
2184 static int composite_bind(struct usb_gadget *gadget,
2185                 struct usb_gadget_driver *gdriver)
2186 {
2187         struct usb_composite_dev        *cdev;
2188         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2189         int                             status = -ENOMEM;
2190
2191         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2192         if (!cdev)
2193                 return status;
2194
2195         spin_lock_init(&cdev->lock);
2196         cdev->gadget = gadget;
2197         set_gadget_data(gadget, cdev);
2198         INIT_LIST_HEAD(&cdev->configs);
2199         INIT_LIST_HEAD(&cdev->gstrings);
2200
2201         status = composite_dev_prepare(composite, cdev);
2202         if (status)
2203                 goto fail;
2204
2205         /* composite gadget needs to assign strings for whole device (like
2206          * serial number), register function drivers, potentially update
2207          * power state and consumption, etc
2208          */
2209         status = composite->bind(cdev);
2210         if (status < 0)
2211                 goto fail;
2212
2213         if (cdev->use_os_string) {
2214                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2215                 if (status)
2216                         goto fail;
2217         }
2218
2219         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2220
2221         /* has userspace failed to provide a serial number? */
2222         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2223                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2224
2225         INFO(cdev, "%s ready\n", composite->name);
2226         return 0;
2227
2228 fail:
2229         __composite_unbind(gadget, false);
2230         return status;
2231 }
2232
2233 /*-------------------------------------------------------------------------*/
2234
2235 void composite_suspend(struct usb_gadget *gadget)
2236 {
2237         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2238         struct usb_function             *f;
2239
2240         /* REVISIT:  should we have config level
2241          * suspend/resume callbacks?
2242          */
2243         DBG(cdev, "suspend\n");
2244         if (cdev->config) {
2245                 list_for_each_entry(f, &cdev->config->functions, list) {
2246                         if (f->suspend)
2247                                 f->suspend(f);
2248                 }
2249         }
2250         if (cdev->driver->suspend)
2251                 cdev->driver->suspend(cdev);
2252
2253         cdev->suspended = 1;
2254
2255         usb_gadget_vbus_draw(gadget, 2);
2256 }
2257
2258 void composite_resume(struct usb_gadget *gadget)
2259 {
2260         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2261         struct usb_function             *f;
2262         u16                             maxpower;
2263
2264         /* REVISIT:  should we have config level
2265          * suspend/resume callbacks?
2266          */
2267         DBG(cdev, "resume\n");
2268         if (cdev->driver->resume)
2269                 cdev->driver->resume(cdev);
2270         if (cdev->config) {
2271                 list_for_each_entry(f, &cdev->config->functions, list) {
2272                         if (f->resume)
2273                                 f->resume(f);
2274                 }
2275
2276                 maxpower = cdev->config->MaxPower;
2277
2278                 usb_gadget_vbus_draw(gadget, maxpower ?
2279                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
2280         }
2281
2282         cdev->suspended = 0;
2283 }
2284
2285 /*-------------------------------------------------------------------------*/
2286
2287 static const struct usb_gadget_driver composite_driver_template = {
2288         .bind           = composite_bind,
2289         .unbind         = composite_unbind,
2290
2291         .setup          = composite_setup,
2292         .reset          = composite_disconnect,
2293         .disconnect     = composite_disconnect,
2294
2295         .suspend        = composite_suspend,
2296         .resume         = composite_resume,
2297
2298         .driver = {
2299                 .owner          = THIS_MODULE,
2300         },
2301 };
2302
2303 /**
2304  * usb_composite_probe() - register a composite driver
2305  * @driver: the driver to register
2306  *
2307  * Context: single threaded during gadget setup
2308  *
2309  * This function is used to register drivers using the composite driver
2310  * framework.  The return value is zero, or a negative errno value.
2311  * Those values normally come from the driver's @bind method, which does
2312  * all the work of setting up the driver to match the hardware.
2313  *
2314  * On successful return, the gadget is ready to respond to requests from
2315  * the host, unless one of its components invokes usb_gadget_disconnect()
2316  * while it was binding.  That would usually be done in order to wait for
2317  * some userspace participation.
2318  */
2319 int usb_composite_probe(struct usb_composite_driver *driver)
2320 {
2321         struct usb_gadget_driver *gadget_driver;
2322
2323         if (!driver || !driver->dev || !driver->bind)
2324                 return -EINVAL;
2325
2326         if (!driver->name)
2327                 driver->name = "composite";
2328
2329         driver->gadget_driver = composite_driver_template;
2330         gadget_driver = &driver->gadget_driver;
2331
2332         gadget_driver->function =  (char *) driver->name;
2333         gadget_driver->driver.name = driver->name;
2334         gadget_driver->max_speed = driver->max_speed;
2335
2336         return usb_gadget_probe_driver(gadget_driver);
2337 }
2338 EXPORT_SYMBOL_GPL(usb_composite_probe);
2339
2340 /**
2341  * usb_composite_unregister() - unregister a composite driver
2342  * @driver: the driver to unregister
2343  *
2344  * This function is used to unregister drivers using the composite
2345  * driver framework.
2346  */
2347 void usb_composite_unregister(struct usb_composite_driver *driver)
2348 {
2349         usb_gadget_unregister_driver(&driver->gadget_driver);
2350 }
2351 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2352
2353 /**
2354  * usb_composite_setup_continue() - Continue with the control transfer
2355  * @cdev: the composite device who's control transfer was kept waiting
2356  *
2357  * This function must be called by the USB function driver to continue
2358  * with the control transfer's data/status stage in case it had requested to
2359  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2360  * can request the composite framework to delay the setup request's data/status
2361  * stages by returning USB_GADGET_DELAYED_STATUS.
2362  */
2363 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2364 {
2365         int                     value;
2366         struct usb_request      *req = cdev->req;
2367         unsigned long           flags;
2368
2369         DBG(cdev, "%s\n", __func__);
2370         spin_lock_irqsave(&cdev->lock, flags);
2371
2372         if (cdev->delayed_status == 0) {
2373                 WARN(cdev, "%s: Unexpected call\n", __func__);
2374
2375         } else if (--cdev->delayed_status == 0) {
2376                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2377                 req->length = 0;
2378                 req->context = cdev;
2379                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2380                 if (value < 0) {
2381                         DBG(cdev, "ep_queue --> %d\n", value);
2382                         req->status = 0;
2383                         composite_setup_complete(cdev->gadget->ep0, req);
2384                 }
2385         }
2386
2387         spin_unlock_irqrestore(&cdev->lock, flags);
2388 }
2389 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2390
2391 static char *composite_default_mfr(struct usb_gadget *gadget)
2392 {
2393         return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2394                          init_utsname()->release, gadget->name);
2395 }
2396
2397 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2398                 struct usb_composite_overwrite *covr)
2399 {
2400         struct usb_device_descriptor    *desc = &cdev->desc;
2401         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2402         struct usb_string               *dev_str = gstr->strings;
2403
2404         if (covr->idVendor)
2405                 desc->idVendor = cpu_to_le16(covr->idVendor);
2406
2407         if (covr->idProduct)
2408                 desc->idProduct = cpu_to_le16(covr->idProduct);
2409
2410         if (covr->bcdDevice)
2411                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2412
2413         if (covr->serial_number) {
2414                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2415                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2416         }
2417         if (covr->manufacturer) {
2418                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2419                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2420
2421         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2422                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2423                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2424                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2425         }
2426
2427         if (covr->product) {
2428                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2429                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2430         }
2431 }
2432 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2433
2434 MODULE_LICENSE("GPL");
2435 MODULE_AUTHOR("David Brownell");