linux/drivers/usb/gadget/composite.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * composite.c - infrastructure for Composite USB Gadgets
   4 *
   5 * Copyright (C) 2006-2008 David Brownell
   6 */
   7
   8/* #define VERBOSE_DEBUG */
   9
  10#include <linux/kallsyms.h>
  11#include <linux/kernel.h>
  12#include <linux/slab.h>
  13#include <linux/module.h>
  14#include <linux/device.h>
  15#include <linux/utsname.h>
  16#include <linux/bitfield.h>
  17
  18#include <linux/usb/composite.h>
  19#include <linux/usb/otg.h>
  20#include <asm/unaligned.h>
  21
  22#include "u_os_desc.h"
  23
  24/**
  25 * struct usb_os_string - represents OS String to be reported by a gadget
  26 * @bLength: total length of the entire descritor, always 0x12
  27 * @bDescriptorType: USB_DT_STRING
  28 * @qwSignature: the OS String proper
  29 * @bMS_VendorCode: code used by the host for subsequent requests
  30 * @bPad: not used, must be zero
  31 */
  32struct usb_os_string {
  33        __u8    bLength;
  34        __u8    bDescriptorType;
  35        __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  36        __u8    bMS_VendorCode;
  37        __u8    bPad;
  38} __packed;
  39
  40/*
  41 * The code in this file is utility code, used to build a gadget driver
  42 * from one or more "function" drivers, one or more "configuration"
  43 * objects, and a "usb_composite_driver" by gluing them together along
  44 * with the relevant device-wide data.
  45 */
  46
  47static struct usb_gadget_strings **get_containers_gs(
  48                struct usb_gadget_string_container *uc)
  49{
  50        return (struct usb_gadget_strings **)uc->stash;
  51}
  52
  53/**
  54 * function_descriptors() - get function descriptors for speed
  55 * @f: the function
  56 * @speed: the speed
  57 *
  58 * Returns the descriptors or NULL if not set.
  59 */
  60static struct usb_descriptor_header **
  61function_descriptors(struct usb_function *f,
  62                     enum usb_device_speed speed)
  63{
  64        struct usb_descriptor_header **descriptors;
  65
  66        /*
  67         * NOTE: we try to help gadget drivers which might not be setting
  68         * max_speed appropriately.
  69         */
  70
  71        switch (speed) {
  72        case USB_SPEED_SUPER_PLUS:
  73                descriptors = f->ssp_descriptors;
  74                if (descriptors)
  75                        break;
  76                fallthrough;
  77        case USB_SPEED_SUPER:
  78                descriptors = f->ss_descriptors;
  79                if (descriptors)
  80                        break;
  81                fallthrough;
  82        case USB_SPEED_HIGH:
  83                descriptors = f->hs_descriptors;
  84                if (descriptors)
  85                        break;
  86                fallthrough;
  87        default:
  88                descriptors = f->fs_descriptors;
  89        }
  90
  91        /*
  92         * if we can't find any descriptors at all, then this gadget deserves to
  93         * Oops with a NULL pointer dereference
  94         */
  95
  96        return descriptors;
  97}
  98
  99/**
 100 * next_desc() - advance to the next desc_type descriptor
 101 * @t: currect pointer within descriptor array
 102 * @desc_type: descriptor type
 103 *
 104 * Return: next desc_type descriptor or NULL
 105 *
 106 * Iterate over @t until either desc_type descriptor found or
 107 * NULL (that indicates end of list) encountered
 108 */
 109static struct usb_descriptor_header**
 110next_desc(struct usb_descriptor_header **t, u8 desc_type)
 111{
 112        for (; *t; t++) {
 113                if ((*t)->bDescriptorType == desc_type)
 114                        return t;
 115        }
 116        return NULL;
 117}
 118
 119/*
 120 * for_each_desc() - iterate over desc_type descriptors in the
 121 * descriptors list
 122 * @start: pointer within descriptor array.
 123 * @iter_desc: desc_type descriptor to use as the loop cursor
 124 * @desc_type: wanted descriptr type
 125 */
 126#define for_each_desc(start, iter_desc, desc_type) \
 127        for (iter_desc = next_desc(start, desc_type); \
 128             iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
 129
 130/**
 131 * config_ep_by_speed_and_alt() - configures the given endpoint
 132 * according to gadget speed.
 133 * @g: pointer to the gadget
 134 * @f: usb function
 135 * @_ep: the endpoint to configure
 136 * @alt: alternate setting number
 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 */
 149int config_ep_by_speed_and_alt(struct usb_gadget *g,
 150                                struct usb_function *f,
 151                                struct usb_ep *_ep,
 152                                u8 alt)
 153{
 154        struct usb_endpoint_descriptor *chosen_desc = NULL;
 155        struct usb_interface_descriptor *int_desc = NULL;
 156        struct usb_descriptor_header **speed_desc = NULL;
 157
 158        struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 159        int want_comp_desc = 0;
 160
 161        struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 162
 163        if (!g || !f || !_ep)
 164                return -EIO;
 165
 166        /* select desired speed */
 167        switch (g->speed) {
 168        case USB_SPEED_SUPER_PLUS:
 169                if (gadget_is_superspeed_plus(g)) {
 170                        speed_desc = f->ssp_descriptors;
 171                        want_comp_desc = 1;
 172                        break;
 173                }
 174                fallthrough;
 175        case USB_SPEED_SUPER:
 176                if (gadget_is_superspeed(g)) {
 177                        speed_desc = f->ss_descriptors;
 178                        want_comp_desc = 1;
 179                        break;
 180                }
 181                fallthrough;
 182        case USB_SPEED_HIGH:
 183                if (gadget_is_dualspeed(g)) {
 184                        speed_desc = f->hs_descriptors;
 185                        break;
 186                }
 187                fallthrough;
 188        default:
 189                speed_desc = f->fs_descriptors;
 190        }
 191
 192        /* find correct alternate setting descriptor */
 193        for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
 194                int_desc = (struct usb_interface_descriptor *)*d_spd;
 195
 196                if (int_desc->bAlternateSetting == alt) {
 197                        speed_desc = d_spd;
 198                        goto intf_found;
 199                }
 200        }
 201        return -EIO;
 202
 203intf_found:
 204        /* find descriptors */
 205        for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
 206                chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 207                if (chosen_desc->bEndpointAddress == _ep->address)
 208                        goto ep_found;
 209        }
 210        return -EIO;
 211
 212ep_found:
 213        /* commit results */
 214        _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 215        _ep->desc = chosen_desc;
 216        _ep->comp_desc = NULL;
 217        _ep->maxburst = 0;
 218        _ep->mult = 1;
 219
 220        if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 221                                usb_endpoint_xfer_int(_ep->desc)))
 222                _ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 223
 224        if (!want_comp_desc)
 225                return 0;
 226
 227        /*
 228         * Companion descriptor should follow EP descriptor
 229         * USB 3.0 spec, #9.6.7
 230         */
 231        comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 232        if (!comp_desc ||
 233            (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 234                return -EIO;
 235        _ep->comp_desc = comp_desc;
 236        if (g->speed >= USB_SPEED_SUPER) {
 237                switch (usb_endpoint_type(_ep->desc)) {
 238                case USB_ENDPOINT_XFER_ISOC:
 239                        /* mult: bits 1:0 of bmAttributes */
 240                        _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 241                        fallthrough;
 242                case USB_ENDPOINT_XFER_BULK:
 243                case USB_ENDPOINT_XFER_INT:
 244                        _ep->maxburst = comp_desc->bMaxBurst + 1;
 245                        break;
 246                default:
 247                        if (comp_desc->bMaxBurst != 0) {
 248                                struct usb_composite_dev *cdev;
 249
 250                                cdev = get_gadget_data(g);
 251                                ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 252                        }
 253                        _ep->maxburst = 1;
 254                        break;
 255                }
 256        }
 257        return 0;
 258}
 259EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
 260
 261/**
 262 * config_ep_by_speed() - configures the given endpoint
 263 * according to gadget speed.
 264 * @g: pointer to the gadget
 265 * @f: usb function
 266 * @_ep: the endpoint to configure
 267 *
 268 * Return: error code, 0 on success
 269 *
 270 * This function chooses the right descriptors for a given
 271 * endpoint according to gadget speed and saves it in the
 272 * endpoint desc field. If the endpoint already has a descriptor
 273 * assigned to it - overwrites it with currently corresponding
 274 * descriptor. The endpoint maxpacket field is updated according
 275 * to the chosen descriptor.
 276 * Note: the supplied function should hold all the descriptors
 277 * for supported speeds
 278 */
 279int config_ep_by_speed(struct usb_gadget *g,
 280                        struct usb_function *f,
 281                        struct usb_ep *_ep)
 282{
 283        return config_ep_by_speed_and_alt(g, f, _ep, 0);
 284}
 285EXPORT_SYMBOL_GPL(config_ep_by_speed);
 286
 287/**
 288 * usb_add_function() - add a function to a configuration
 289 * @config: the configuration
 290 * @function: the function being added
 291 * Context: single threaded during gadget setup
 292 *
 293 * After initialization, each configuration must have one or more
 294 * functions added to it.  Adding a function involves calling its @bind()
 295 * method to allocate resources such as interface and string identifiers
 296 * and endpoints.
 297 *
 298 * This function returns the value of the function's bind(), which is
 299 * zero for success else a negative errno value.
 300 */
 301int usb_add_function(struct usb_configuration *config,
 302                struct usb_function *function)
 303{
 304        int     value = -EINVAL;
 305
 306        DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 307                        function->name, function,
 308                        config->label, config);
 309
 310        if (!function->set_alt || !function->disable)
 311                goto done;
 312
 313        function->config = config;
 314        list_add_tail(&function->list, &config->functions);
 315
 316        if (function->bind_deactivated) {
 317                value = usb_function_deactivate(function);
 318                if (value)
 319                        goto done;
 320        }
 321
 322        /* REVISIT *require* function->bind? */
 323        if (function->bind) {
 324                value = function->bind(config, function);
 325                if (value < 0) {
 326                        list_del(&function->list);
 327                        function->config = NULL;
 328                }
 329        } else
 330                value = 0;
 331
 332        /* We allow configurations that don't work at both speeds.
 333         * If we run into a lowspeed Linux system, treat it the same
 334         * as full speed ... it's the function drivers that will need
 335         * to avoid bulk and ISO transfers.
 336         */
 337        if (!config->fullspeed && function->fs_descriptors)
 338                config->fullspeed = true;
 339        if (!config->highspeed && function->hs_descriptors)
 340                config->highspeed = true;
 341        if (!config->superspeed && function->ss_descriptors)
 342                config->superspeed = true;
 343        if (!config->superspeed_plus && function->ssp_descriptors)
 344                config->superspeed_plus = true;
 345
 346done:
 347        if (value)
 348                DBG(config->cdev, "adding '%s'/%p --> %d\n",
 349                                function->name, function, value);
 350        return value;
 351}
 352EXPORT_SYMBOL_GPL(usb_add_function);
 353
 354void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 355{
 356        if (f->disable)
 357                f->disable(f);
 358
 359        bitmap_zero(f->endpoints, 32);
 360        list_del(&f->list);
 361        if (f->unbind)
 362                f->unbind(c, f);
 363
 364        if (f->bind_deactivated)
 365                usb_function_activate(f);
 366}
 367EXPORT_SYMBOL_GPL(usb_remove_function);
 368
 369/**
 370 * usb_function_deactivate - prevent function and gadget enumeration
 371 * @function: the function that isn't yet ready to respond
 372 *
 373 * Blocks response of the gadget driver to host enumeration by
 374 * preventing the data line pullup from being activated.  This is
 375 * normally called during @bind() processing to change from the
 376 * initial "ready to respond" state, or when a required resource
 377 * becomes available.
 378 *
 379 * For example, drivers that serve as a passthrough to a userspace
 380 * daemon can block enumeration unless that daemon (such as an OBEX,
 381 * MTP, or print server) is ready to handle host requests.
 382 *
 383 * Not all systems support software control of their USB peripheral
 384 * data pullups.
 385 *
 386 * Returns zero on success, else negative errno.
 387 */
 388int usb_function_deactivate(struct usb_function *function)
 389{
 390        struct usb_composite_dev        *cdev = function->config->cdev;
 391        unsigned long                   flags;
 392        int                             status = 0;
 393
 394        spin_lock_irqsave(&cdev->lock, flags);
 395
 396        if (cdev->deactivations == 0) {
 397                spin_unlock_irqrestore(&cdev->lock, flags);
 398                status = usb_gadget_deactivate(cdev->gadget);
 399                spin_lock_irqsave(&cdev->lock, flags);
 400        }
 401        if (status == 0)
 402                cdev->deactivations++;
 403
 404        spin_unlock_irqrestore(&cdev->lock, flags);
 405        return status;
 406}
 407EXPORT_SYMBOL_GPL(usb_function_deactivate);
 408
 409/**
 410 * usb_function_activate - allow function and gadget enumeration
 411 * @function: function on which usb_function_activate() was called
 412 *
 413 * Reverses effect of usb_function_deactivate().  If no more functions
 414 * are delaying their activation, the gadget driver will respond to
 415 * host enumeration procedures.
 416 *
 417 * Returns zero on success, else negative errno.
 418 */
 419int usb_function_activate(struct usb_function *function)
 420{
 421        struct usb_composite_dev        *cdev = function->config->cdev;
 422        unsigned long                   flags;
 423        int                             status = 0;
 424
 425        spin_lock_irqsave(&cdev->lock, flags);
 426
 427        if (WARN_ON(cdev->deactivations == 0))
 428                status = -EINVAL;
 429        else {
 430                cdev->deactivations--;
 431                if (cdev->deactivations == 0) {
 432                        spin_unlock_irqrestore(&cdev->lock, flags);
 433                        status = usb_gadget_activate(cdev->gadget);
 434                        spin_lock_irqsave(&cdev->lock, flags);
 435                }
 436        }
 437
 438        spin_unlock_irqrestore(&cdev->lock, flags);
 439        return status;
 440}
 441EXPORT_SYMBOL_GPL(usb_function_activate);
 442
 443/**
 444 * usb_interface_id() - allocate an unused interface ID
 445 * @config: configuration associated with the interface
 446 * @function: function handling the interface
 447 * Context: single threaded during gadget setup
 448 *
 449 * usb_interface_id() is called from usb_function.bind() callbacks to
 450 * allocate new interface IDs.  The function driver will then store that
 451 * ID in interface, association, CDC union, and other descriptors.  It
 452 * will also handle any control requests targeted at that interface,
 453 * particularly changing its altsetting via set_alt().  There may
 454 * also be class-specific or vendor-specific requests to handle.
 455 *
 456 * All interface identifier should be allocated using this routine, to
 457 * ensure that for example different functions don't wrongly assign
 458 * different meanings to the same identifier.  Note that since interface
 459 * identifiers are configuration-specific, functions used in more than
 460 * one configuration (or more than once in a given configuration) need
 461 * multiple versions of the relevant descriptors.
 462 *
 463 * Returns the interface ID which was allocated; or -ENODEV if no
 464 * more interface IDs can be allocated.
 465 */
 466int usb_interface_id(struct usb_configuration *config,
 467                struct usb_function *function)
 468{
 469        unsigned id = config->next_interface_id;
 470
 471        if (id < MAX_CONFIG_INTERFACES) {
 472                config->interface[id] = function;
 473                config->next_interface_id = id + 1;
 474                return id;
 475        }
 476        return -ENODEV;
 477}
 478EXPORT_SYMBOL_GPL(usb_interface_id);
 479
 480static u8 encode_bMaxPower(enum usb_device_speed speed,
 481                struct usb_configuration *c)
 482{
 483        unsigned val;
 484
 485        if (c->MaxPower)
 486                val = c->MaxPower;
 487        else
 488                val = CONFIG_USB_GADGET_VBUS_DRAW;
 489        if (!val)
 490                return 0;
 491        if (speed < USB_SPEED_SUPER)
 492                return min(val, 500U) / 2;
 493        else
 494                /*
 495                 * USB 3.x supports up to 900mA, but since 900 isn't divisible
 496                 * by 8 the integral division will effectively cap to 896mA.
 497                 */
 498                return min(val, 900U) / 8;
 499}
 500
 501static int config_buf(struct usb_configuration *config,
 502                enum usb_device_speed speed, void *buf, u8 type)
 503{
 504        struct usb_config_descriptor    *c = buf;
 505        void                            *next = buf + USB_DT_CONFIG_SIZE;
 506        int                             len;
 507        struct usb_function             *f;
 508        int                             status;
 509
 510        len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 511        /* write the config descriptor */
 512        c = buf;
 513        c->bLength = USB_DT_CONFIG_SIZE;
 514        c->bDescriptorType = type;
 515        /* wTotalLength is written later */
 516        c->bNumInterfaces = config->next_interface_id;
 517        c->bConfigurationValue = config->bConfigurationValue;
 518        c->iConfiguration = config->iConfiguration;
 519        c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 520        c->bMaxPower = encode_bMaxPower(speed, config);
 521
 522        /* There may be e.g. OTG descriptors */
 523        if (config->descriptors) {
 524                status = usb_descriptor_fillbuf(next, len,
 525                                config->descriptors);
 526                if (status < 0)
 527                        return status;
 528                len -= status;
 529                next += status;
 530        }
 531
 532        /* add each function's descriptors */
 533        list_for_each_entry(f, &config->functions, list) {
 534                struct usb_descriptor_header **descriptors;
 535
 536                descriptors = function_descriptors(f, speed);
 537                if (!descriptors)
 538                        continue;
 539                status = usb_descriptor_fillbuf(next, len,
 540                        (const struct usb_descriptor_header **) descriptors);
 541                if (status < 0)
 542                        return status;
 543                len -= status;
 544                next += status;
 545        }
 546
 547        len = next - buf;
 548        c->wTotalLength = cpu_to_le16(len);
 549        return len;
 550}
 551
 552static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 553{
 554        struct usb_gadget               *gadget = cdev->gadget;
 555        struct usb_configuration        *c;
 556        struct list_head                *pos;
 557        u8                              type = w_value >> 8;
 558        enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 559
 560        if (gadget->speed >= USB_SPEED_SUPER)
 561                speed = gadget->speed;
 562        else if (gadget_is_dualspeed(gadget)) {
 563                int     hs = 0;
 564                if (gadget->speed == USB_SPEED_HIGH)
 565                        hs = 1;
 566                if (type == USB_DT_OTHER_SPEED_CONFIG)
 567                        hs = !hs;
 568                if (hs)
 569                        speed = USB_SPEED_HIGH;
 570
 571        }
 572
 573        /* This is a lookup by config *INDEX* */
 574        w_value &= 0xff;
 575
 576        pos = &cdev->configs;
 577        c = cdev->os_desc_config;
 578        if (c)
 579                goto check_config;
 580
 581        while ((pos = pos->next) !=  &cdev->configs) {
 582                c = list_entry(pos, typeof(*c), list);
 583
 584                /* skip OS Descriptors config which is handled separately */
 585                if (c == cdev->os_desc_config)
 586                        continue;
 587
 588check_config:
 589                /* ignore configs that won't work at this speed */
 590                switch (speed) {
 591                case USB_SPEED_SUPER_PLUS:
 592                        if (!c->superspeed_plus)
 593                                continue;
 594                        break;
 595                case USB_SPEED_SUPER:
 596                        if (!c->superspeed)
 597                                continue;
 598                        break;
 599                case USB_SPEED_HIGH:
 600                        if (!c->highspeed)
 601                                continue;
 602                        break;
 603                default:
 604                        if (!c->fullspeed)
 605                                continue;
 606                }
 607
 608                if (w_value == 0)
 609                        return config_buf(c, speed, cdev->req->buf, type);
 610                w_value--;
 611        }
 612        return -EINVAL;
 613}
 614
 615static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 616{
 617        struct usb_gadget               *gadget = cdev->gadget;
 618        struct usb_configuration        *c;
 619        unsigned                        count = 0;
 620        int                             hs = 0;
 621        int                             ss = 0;
 622        int                             ssp = 0;
 623
 624        if (gadget_is_dualspeed(gadget)) {
 625                if (gadget->speed == USB_SPEED_HIGH)
 626                        hs = 1;
 627                if (gadget->speed == USB_SPEED_SUPER)
 628                        ss = 1;
 629                if (gadget->speed == USB_SPEED_SUPER_PLUS)
 630                        ssp = 1;
 631                if (type == USB_DT_DEVICE_QUALIFIER)
 632                        hs = !hs;
 633        }
 634        list_for_each_entry(c, &cdev->configs, list) {
 635                /* ignore configs that won't work at this speed */
 636                if (ssp) {
 637                        if (!c->superspeed_plus)
 638                                continue;
 639                } else if (ss) {
 640                        if (!c->superspeed)
 641                                continue;
 642                } else if (hs) {
 643                        if (!c->highspeed)
 644                                continue;
 645                } else {
 646                        if (!c->fullspeed)
 647                                continue;
 648                }
 649                count++;
 650        }
 651        return count;
 652}
 653
 654/**
 655 * bos_desc() - prepares the BOS descriptor.
 656 * @cdev: pointer to usb_composite device to generate the bos
 657 *      descriptor for
 658 *
 659 * This function generates the BOS (Binary Device Object)
 660 * descriptor and its device capabilities descriptors. The BOS
 661 * descriptor should be supported by a SuperSpeed device.
 662 */
 663static int bos_desc(struct usb_composite_dev *cdev)
 664{
 665        struct usb_ext_cap_descriptor   *usb_ext;
 666        struct usb_dcd_config_params    dcd_config_params;
 667        struct usb_bos_descriptor       *bos = cdev->req->buf;
 668        unsigned int                    besl = 0;
 669
 670        bos->bLength = USB_DT_BOS_SIZE;
 671        bos->bDescriptorType = USB_DT_BOS;
 672
 673        bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 674        bos->bNumDeviceCaps = 0;
 675
 676        /* Get Controller configuration */
 677        if (cdev->gadget->ops->get_config_params) {
 678                cdev->gadget->ops->get_config_params(cdev->gadget,
 679                                                     &dcd_config_params);
 680        } else {
 681                dcd_config_params.besl_baseline =
 682                        USB_DEFAULT_BESL_UNSPECIFIED;
 683                dcd_config_params.besl_deep =
 684                        USB_DEFAULT_BESL_UNSPECIFIED;
 685                dcd_config_params.bU1devExitLat =
 686                        USB_DEFAULT_U1_DEV_EXIT_LAT;
 687                dcd_config_params.bU2DevExitLat =
 688                        cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 689        }
 690
 691        if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
 692                besl = USB_BESL_BASELINE_VALID |
 693                        USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
 694
 695        if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
 696                besl |= USB_BESL_DEEP_VALID |
 697                        USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
 698
 699        /*
 700         * A SuperSpeed device shall include the USB2.0 extension descriptor
 701         * and shall support LPM when operating in USB2.0 HS mode.
 702         */
 703        usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 704        bos->bNumDeviceCaps++;
 705        le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 706        usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 707        usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 708        usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 709        usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
 710                                            USB_BESL_SUPPORT | besl);
 711
 712        /*
 713         * The Superspeed USB Capability descriptor shall be implemented by all
 714         * SuperSpeed devices.
 715         */
 716        if (gadget_is_superspeed(cdev->gadget)) {
 717                struct usb_ss_cap_descriptor *ss_cap;
 718
 719                ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 720                bos->bNumDeviceCaps++;
 721                le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 722                ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 723                ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 724                ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 725                ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 726                ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 727                                                      USB_FULL_SPEED_OPERATION |
 728                                                      USB_HIGH_SPEED_OPERATION |
 729                                                      USB_5GBPS_OPERATION);
 730                ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 731                ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 732                ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 733        }
 734
 735        /* The SuperSpeedPlus USB Device Capability descriptor */
 736        if (gadget_is_superspeed_plus(cdev->gadget)) {
 737                struct usb_ssp_cap_descriptor *ssp_cap;
 738                u8 ssac = 1;
 739                u8 ssic;
 740                int i;
 741
 742                if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x2)
 743                        ssac = 3;
 744
 745                /*
 746                 * Paired RX and TX sublink speed attributes share
 747                 * the same SSID.
 748                 */
 749                ssic = (ssac + 1) / 2 - 1;
 750
 751                ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 752                bos->bNumDeviceCaps++;
 753
 754                le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
 755                ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
 756                ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 757                ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 758                ssp_cap->bReserved = 0;
 759                ssp_cap->wReserved = 0;
 760
 761                ssp_cap->bmAttributes =
 762                        cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
 763                                    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
 764
 765                ssp_cap->wFunctionalitySupport =
 766                        cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
 767                                    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
 768                                    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 769
 770                /*
 771                 * Use 1 SSID if the gadget supports up to gen2x1 or not
 772                 * specified:
 773                 * - SSID 0 for symmetric RX/TX sublink speed of 10 Gbps.
 774                 *
 775                 * Use 1 SSID if the gadget supports up to gen1x2:
 776                 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 777                 *
 778                 * Use 2 SSIDs if the gadget supports up to gen2x2:
 779                 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 780                 * - SSID 1 for symmetric RX/TX sublink speed of 10 Gbps.
 781                 */
 782                for (i = 0; i < ssac + 1; i++) {
 783                        u8 ssid;
 784                        u8 mantissa;
 785                        u8 type;
 786
 787                        ssid = i >> 1;
 788
 789                        if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x1 ||
 790                            cdev->gadget->max_ssp_rate == USB_SSP_GEN_UNKNOWN)
 791                                mantissa = 10;
 792                        else
 793                                mantissa = 5 << ssid;
 794
 795                        if (i % 2)
 796                                type = USB_SSP_SUBLINK_SPEED_ST_SYM_TX;
 797                        else
 798                                type = USB_SSP_SUBLINK_SPEED_ST_SYM_RX;
 799
 800                        ssp_cap->bmSublinkSpeedAttr[i] =
 801                                cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ssid) |
 802                                            FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE,
 803                                                       USB_SSP_SUBLINK_SPEED_LSE_GBPS) |
 804                                            FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, type) |
 805                                            FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP,
 806                                                       USB_SSP_SUBLINK_SPEED_LP_SSP) |
 807                                            FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, mantissa));
 808                }
 809        }
 810
 811        return le16_to_cpu(bos->wTotalLength);
 812}
 813
 814static void device_qual(struct usb_composite_dev *cdev)
 815{
 816        struct usb_qualifier_descriptor *qual = cdev->req->buf;
 817
 818        qual->bLength = sizeof(*qual);
 819        qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 820        /* POLICY: same bcdUSB and device type info at both speeds */
 821        qual->bcdUSB = cdev->desc.bcdUSB;
 822        qual->bDeviceClass = cdev->desc.bDeviceClass;
 823        qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 824        qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 825        /* ASSUME same EP0 fifo size at both speeds */
 826        qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 827        qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 828        qual->bRESERVED = 0;
 829}
 830
 831/*-------------------------------------------------------------------------*/
 832
 833static void reset_config(struct usb_composite_dev *cdev)
 834{
 835        struct usb_function             *f;
 836
 837        DBG(cdev, "reset config\n");
 838
 839        list_for_each_entry(f, &cdev->config->functions, list) {
 840                if (f->disable)
 841                        f->disable(f);
 842
 843                bitmap_zero(f->endpoints, 32);
 844        }
 845        cdev->config = NULL;
 846        cdev->delayed_status = 0;
 847}
 848
 849static int set_config(struct usb_composite_dev *cdev,
 850                const struct usb_ctrlrequest *ctrl, unsigned number)
 851{
 852        struct usb_gadget       *gadget = cdev->gadget;
 853        struct usb_configuration *c = NULL;
 854        int                     result = -EINVAL;
 855        unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 856        int                     tmp;
 857
 858        if (number) {
 859                list_for_each_entry(c, &cdev->configs, list) {
 860                        if (c->bConfigurationValue == number) {
 861                                /*
 862                                 * We disable the FDs of the previous
 863                                 * configuration only if the new configuration
 864                                 * is a valid one
 865                                 */
 866                                if (cdev->config)
 867                                        reset_config(cdev);
 868                                result = 0;
 869                                break;
 870                        }
 871                }
 872                if (result < 0)
 873                        goto done;
 874        } else { /* Zero configuration value - need to reset the config */
 875                if (cdev->config)
 876                        reset_config(cdev);
 877                result = 0;
 878        }
 879
 880        DBG(cdev, "%s config #%d: %s\n",
 881            usb_speed_string(gadget->speed),
 882            number, c ? c->label : "unconfigured");
 883
 884        if (!c)
 885                goto done;
 886
 887        usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 888        cdev->config = c;
 889
 890        /* Initialize all interfaces by setting them to altsetting zero. */
 891        for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 892                struct usb_function     *f = c->interface[tmp];
 893                struct usb_descriptor_header **descriptors;
 894
 895                if (!f)
 896                        break;
 897
 898                /*
 899                 * Record which endpoints are used by the function. This is used
 900                 * to dispatch control requests targeted at that endpoint to the
 901                 * function's setup callback instead of the current
 902                 * configuration's setup callback.
 903                 */
 904                descriptors = function_descriptors(f, gadget->speed);
 905
 906                for (; *descriptors; ++descriptors) {
 907                        struct usb_endpoint_descriptor *ep;
 908                        int addr;
 909
 910                        if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 911                                continue;
 912
 913                        ep = (struct usb_endpoint_descriptor *)*descriptors;
 914                        addr = ((ep->bEndpointAddress & 0x80) >> 3)
 915                             |  (ep->bEndpointAddress & 0x0f);
 916                        set_bit(addr, f->endpoints);
 917                }
 918
 919                result = f->set_alt(f, tmp, 0);
 920                if (result < 0) {
 921                        DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 922                                        tmp, f->name, f, result);
 923
 924                        reset_config(cdev);
 925                        goto done;
 926                }
 927
 928                if (result == USB_GADGET_DELAYED_STATUS) {
 929                        DBG(cdev,
 930                         "%s: interface %d (%s) requested delayed status\n",
 931                                        __func__, tmp, f->name);
 932                        cdev->delayed_status++;
 933                        DBG(cdev, "delayed_status count %d\n",
 934                                        cdev->delayed_status);
 935                }
 936        }
 937
 938        /* when we return, be sure our power usage is valid */
 939        power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 940        if (gadget->speed < USB_SPEED_SUPER)
 941                power = min(power, 500U);
 942        else
 943                power = min(power, 900U);
 944done:
 945        if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
 946                usb_gadget_set_selfpowered(gadget);
 947        else
 948                usb_gadget_clear_selfpowered(gadget);
 949
 950        usb_gadget_vbus_draw(gadget, power);
 951        if (result >= 0 && cdev->delayed_status)
 952                result = USB_GADGET_DELAYED_STATUS;
 953        return result;
 954}
 955
 956int usb_add_config_only(struct usb_composite_dev *cdev,
 957                struct usb_configuration *config)
 958{
 959        struct usb_configuration *c;
 960
 961        if (!config->bConfigurationValue)
 962                return -EINVAL;
 963
 964        /* Prevent duplicate configuration identifiers */
 965        list_for_each_entry(c, &cdev->configs, list) {
 966                if (c->bConfigurationValue == config->bConfigurationValue)
 967                        return -EBUSY;
 968        }
 969
 970        config->cdev = cdev;
 971        list_add_tail(&config->list, &cdev->configs);
 972
 973        INIT_LIST_HEAD(&config->functions);
 974        config->next_interface_id = 0;
 975        memset(config->interface, 0, sizeof(config->interface));
 976
 977        return 0;
 978}
 979EXPORT_SYMBOL_GPL(usb_add_config_only);
 980
 981/**
 982 * usb_add_config() - add a configuration to a device.
 983 * @cdev: wraps the USB gadget
 984 * @config: the configuration, with bConfigurationValue assigned
 985 * @bind: the configuration's bind function
 986 * Context: single threaded during gadget setup
 987 *
 988 * One of the main tasks of a composite @bind() routine is to
 989 * add each of the configurations it supports, using this routine.
 990 *
 991 * This function returns the value of the configuration's @bind(), which
 992 * is zero for success else a negative errno value.  Binding configurations
 993 * assigns global resources including string IDs, and per-configuration
 994 * resources such as interface IDs and endpoints.
 995 */
 996int usb_add_config(struct usb_composite_dev *cdev,
 997                struct usb_configuration *config,
 998                int (*bind)(struct usb_configuration *))
 999{
1000        int                             status = -EINVAL;
1001
1002        if (!bind)
1003                goto done;
1004
1005        DBG(cdev, "adding config #%u '%s'/%p\n",
1006                        config->bConfigurationValue,
1007                        config->label, config);
1008
1009        status = usb_add_config_only(cdev, config);
1010        if (status)
1011                goto done;
1012
1013        status = bind(config);
1014        if (status < 0) {
1015                while (!list_empty(&config->functions)) {
1016                        struct usb_function             *f;
1017
1018                        f = list_first_entry(&config->functions,
1019                                        struct usb_function, list);
1020                        list_del(&f->list);
1021                        if (f->unbind) {
1022                                DBG(cdev, "unbind function '%s'/%p\n",
1023                                        f->name, f);
1024                                f->unbind(config, f);
1025                                /* may free memory for "f" */
1026                        }
1027                }
1028                list_del(&config->list);
1029                config->cdev = NULL;
1030        } else {
1031                unsigned        i;
1032
1033                DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1034                        config->bConfigurationValue, config,
1035                        config->superspeed_plus ? " superplus" : "",
1036                        config->superspeed ? " super" : "",
1037                        config->highspeed ? " high" : "",
1038                        config->fullspeed
1039                                ? (gadget_is_dualspeed(cdev->gadget)
1040                                        ? " full"
1041                                        : " full/low")
1042                                : "");
1043
1044                for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1045                        struct usb_function     *f = config->interface[i];
1046
1047                        if (!f)
1048                                continue;
1049                        DBG(cdev, "  interface %d = %s/%p\n",
1050                                i, f->name, f);
1051                }
1052        }
1053
1054        /* set_alt(), or next bind(), sets up ep->claimed as needed */
1055        usb_ep_autoconfig_reset(cdev->gadget);
1056
1057done:
1058        if (status)
1059                DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1060                                config->bConfigurationValue, status);
1061        return status;
1062}
1063EXPORT_SYMBOL_GPL(usb_add_config);
1064
1065static void remove_config(struct usb_composite_dev *cdev,
1066                              struct usb_configuration *config)
1067{
1068        while (!list_empty(&config->functions)) {
1069                struct usb_function             *f;
1070
1071                f = list_first_entry(&config->functions,
1072                                struct usb_function, list);
1073
1074                usb_remove_function(config, f);
1075        }
1076        list_del(&config->list);
1077        if (config->unbind) {
1078                DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1079                config->unbind(config);
1080                        /* may free memory for "c" */
1081        }
1082}
1083
1084/**
1085 * usb_remove_config() - remove a configuration from a device.
1086 * @cdev: wraps the USB gadget
1087 * @config: the configuration
1088 *
1089 * Drivers must call usb_gadget_disconnect before calling this function
1090 * to disconnect the device from the host and make sure the host will not
1091 * try to enumerate the device while we are changing the config list.
1092 */
1093void usb_remove_config(struct usb_composite_dev *cdev,
1094                      struct usb_configuration *config)
1095{
1096        unsigned long flags;
1097
1098        spin_lock_irqsave(&cdev->lock, flags);
1099
1100        if (cdev->config == config)
1101                reset_config(cdev);
1102
1103        spin_unlock_irqrestore(&cdev->lock, flags);
1104
1105        remove_config(cdev, config);
1106}
1107
1108/*-------------------------------------------------------------------------*/
1109
1110/* We support strings in multiple languages ... string descriptor zero
1111 * says which languages are supported.  The typical case will be that
1112 * only one language (probably English) is used, with i18n handled on
1113 * the host side.
1114 */
1115
1116static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1117{
1118        const struct usb_gadget_strings *s;
1119        __le16                          language;
1120        __le16                          *tmp;
1121
1122        while (*sp) {
1123                s = *sp;
1124                language = cpu_to_le16(s->language);
1125                for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1126                        if (*tmp == language)
1127                                goto repeat;
1128                }
1129                *tmp++ = language;
1130repeat:
1131                sp++;
1132        }
1133}
1134
1135static int lookup_string(
1136        struct usb_gadget_strings       **sp,
1137        void                            *buf,
1138        u16                             language,
1139        int                             id
1140)
1141{
1142        struct usb_gadget_strings       *s;
1143        int                             value;
1144
1145        while (*sp) {
1146                s = *sp++;
1147                if (s->language != language)
1148                        continue;
1149                value = usb_gadget_get_string(s, id, buf);
1150                if (value > 0)
1151                        return value;
1152        }
1153        return -EINVAL;
1154}
1155
1156static int get_string(struct usb_composite_dev *cdev,
1157                void *buf, u16 language, int id)
1158{
1159        struct usb_composite_driver     *composite = cdev->driver;
1160        struct usb_gadget_string_container *uc;
1161        struct usb_configuration        *c;
1162        struct usb_function             *f;
1163        int                             len;
1164
1165        /* Yes, not only is USB's i18n support probably more than most
1166         * folk will ever care about ... also, it's all supported here.
1167         * (Except for UTF8 support for Unicode's "Astral Planes".)
1168         */
1169
1170        /* 0 == report all available language codes */
1171        if (id == 0) {
1172                struct usb_string_descriptor    *s = buf;
1173                struct usb_gadget_strings       **sp;
1174
1175                memset(s, 0, 256);
1176                s->bDescriptorType = USB_DT_STRING;
1177
1178                sp = composite->strings;
1179                if (sp)
1180                        collect_langs(sp, s->wData);
1181
1182                list_for_each_entry(c, &cdev->configs, list) {
1183                        sp = c->strings;
1184                        if (sp)
1185                                collect_langs(sp, s->wData);
1186
1187                        list_for_each_entry(f, &c->functions, list) {
1188                                sp = f->strings;
1189                                if (sp)
1190                                        collect_langs(sp, s->wData);
1191                        }
1192                }
1193                list_for_each_entry(uc, &cdev->gstrings, list) {
1194                        struct usb_gadget_strings **sp;
1195
1196                        sp = get_containers_gs(uc);
1197                        collect_langs(sp, s->wData);
1198                }
1199
1200                for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1201                        continue;
1202                if (!len)
1203                        return -EINVAL;
1204
1205                s->bLength = 2 * (len + 1);
1206                return s->bLength;
1207        }
1208
1209        if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1210                struct usb_os_string *b = buf;
1211                b->bLength = sizeof(*b);
1212                b->bDescriptorType = USB_DT_STRING;
1213                compiletime_assert(
1214                        sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1215                        "qwSignature size must be equal to qw_sign");
1216                memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1217                b->bMS_VendorCode = cdev->b_vendor_code;
1218                b->bPad = 0;
1219                return sizeof(*b);
1220        }
1221
1222        list_for_each_entry(uc, &cdev->gstrings, list) {
1223                struct usb_gadget_strings **sp;
1224
1225                sp = get_containers_gs(uc);
1226                len = lookup_string(sp, buf, language, id);
1227                if (len > 0)
1228                        return len;
1229        }
1230
1231        /* String IDs are device-scoped, so we look up each string
1232         * table we're told about.  These lookups are infrequent;
1233         * simpler-is-better here.
1234         */
1235        if (composite->strings) {
1236                len = lookup_string(composite->strings, buf, language, id);
1237                if (len > 0)
1238                        return len;
1239        }
1240        list_for_each_entry(c, &cdev->configs, list) {
1241                if (c->strings) {
1242                        len = lookup_string(c->strings, buf, language, id);
1243                        if (len > 0)
1244                                return len;
1245                }
1246                list_for_each_entry(f, &c->functions, list) {
1247                        if (!f->strings)
1248                                continue;
1249                        len = lookup_string(f->strings, buf, language, id);
1250                        if (len > 0)
1251                                return len;
1252                }
1253        }
1254        return -EINVAL;
1255}
1256
1257/**
1258 * usb_string_id() - allocate an unused string ID
1259 * @cdev: the device whose string descriptor IDs are being allocated
1260 * Context: single threaded during gadget setup
1261 *
1262 * @usb_string_id() is called from bind() callbacks to allocate
1263 * string IDs.  Drivers for functions, configurations, or gadgets will
1264 * then store that ID in the appropriate descriptors and string table.
1265 *
1266 * All string identifier should be allocated using this,
1267 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1268 * that for example different functions don't wrongly assign different
1269 * meanings to the same identifier.
1270 */
1271int usb_string_id(struct usb_composite_dev *cdev)
1272{
1273        if (cdev->next_string_id < 254) {
1274                /* string id 0 is reserved by USB spec for list of
1275                 * supported languages */
1276                /* 255 reserved as well? -- mina86 */
1277                cdev->next_string_id++;
1278                return cdev->next_string_id;
1279        }
1280        return -ENODEV;
1281}
1282EXPORT_SYMBOL_GPL(usb_string_id);
1283
1284/**
1285 * usb_string_ids_tab() - allocate unused string IDs in batch
1286 * @cdev: the device whose string descriptor IDs are being allocated
1287 * @str: an array of usb_string objects to assign numbers to
1288 * Context: single threaded during gadget setup
1289 *
1290 * @usb_string_ids() is called from bind() callbacks to allocate
1291 * string IDs.  Drivers for functions, configurations, or gadgets will
1292 * then copy IDs from the string table to the appropriate descriptors
1293 * and string table for other languages.
1294 *
1295 * All string identifier should be allocated using this,
1296 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1297 * example different functions don't wrongly assign different meanings
1298 * to the same identifier.
1299 */
1300int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1301{
1302        int next = cdev->next_string_id;
1303
1304        for (; str->s; ++str) {
1305                if (unlikely(next >= 254))
1306                        return -ENODEV;
1307                str->id = ++next;
1308        }
1309
1310        cdev->next_string_id = next;
1311
1312        return 0;
1313}
1314EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1315
1316static struct usb_gadget_string_container *copy_gadget_strings(
1317                struct usb_gadget_strings **sp, unsigned n_gstrings,
1318                unsigned n_strings)
1319{
1320        struct usb_gadget_string_container *uc;
1321        struct usb_gadget_strings **gs_array;
1322        struct usb_gadget_strings *gs;
1323        struct usb_string *s;
1324        unsigned mem;
1325        unsigned n_gs;
1326        unsigned n_s;
1327        void *stash;
1328
1329        mem = sizeof(*uc);
1330        mem += sizeof(void *) * (n_gstrings + 1);
1331        mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1332        mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1333        uc = kmalloc(mem, GFP_KERNEL);
1334        if (!uc)
1335                return ERR_PTR(-ENOMEM);
1336        gs_array = get_containers_gs(uc);
1337        stash = uc->stash;
1338        stash += sizeof(void *) * (n_gstrings + 1);
1339        for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1340                struct usb_string *org_s;
1341
1342                gs_array[n_gs] = stash;
1343                gs = gs_array[n_gs];
1344                stash += sizeof(struct usb_gadget_strings);
1345                gs->language = sp[n_gs]->language;
1346                gs->strings = stash;
1347                org_s = sp[n_gs]->strings;
1348
1349                for (n_s = 0; n_s < n_strings; n_s++) {
1350                        s = stash;
1351                        stash += sizeof(struct usb_string);
1352                        if (org_s->s)
1353                                s->s = org_s->s;
1354                        else
1355                                s->s = "";
1356                        org_s++;
1357                }
1358                s = stash;
1359                s->s = NULL;
1360                stash += sizeof(struct usb_string);
1361
1362        }
1363        gs_array[n_gs] = NULL;
1364        return uc;
1365}
1366
1367/**
1368 * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1369 * @cdev: the device whose string descriptor IDs are being allocated
1370 * and attached.
1371 * @sp: an array of usb_gadget_strings to attach.
1372 * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1373 *
1374 * This function will create a deep copy of usb_gadget_strings and usb_string
1375 * and attach it to the cdev. The actual string (usb_string.s) will not be
1376 * copied but only a referenced will be made. The struct usb_gadget_strings
1377 * array may contain multiple languages and should be NULL terminated.
1378 * The ->language pointer of each struct usb_gadget_strings has to contain the
1379 * same amount of entries.
1380 * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1381 * usb_string entry of es-ES contains the translation of the first usb_string
1382 * entry of en-US. Therefore both entries become the same id assign.
1383 */
1384struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1385                struct usb_gadget_strings **sp, unsigned n_strings)
1386{
1387        struct usb_gadget_string_container *uc;
1388        struct usb_gadget_strings **n_gs;
1389        unsigned n_gstrings = 0;
1390        unsigned i;
1391        int ret;
1392
1393        for (i = 0; sp[i]; i++)
1394                n_gstrings++;
1395
1396        if (!n_gstrings)
1397                return ERR_PTR(-EINVAL);
1398
1399        uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1400        if (IS_ERR(uc))
1401                return ERR_CAST(uc);
1402
1403        n_gs = get_containers_gs(uc);
1404        ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1405        if (ret)
1406                goto err;
1407
1408        for (i = 1; i < n_gstrings; i++) {
1409                struct usb_string *m_s;
1410                struct usb_string *s;
1411                unsigned n;
1412
1413                m_s = n_gs[0]->strings;
1414                s = n_gs[i]->strings;
1415                for (n = 0; n < n_strings; n++) {
1416                        s->id = m_s->id;
1417                        s++;
1418                        m_s++;
1419                }
1420        }
1421        list_add_tail(&uc->list, &cdev->gstrings);
1422        return n_gs[0]->strings;
1423err:
1424        kfree(uc);
1425        return ERR_PTR(ret);
1426}
1427EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1428
1429/**
1430 * usb_string_ids_n() - allocate unused string IDs in batch
1431 * @c: the device whose string descriptor IDs are being allocated
1432 * @n: number of string IDs to allocate
1433 * Context: single threaded during gadget setup
1434 *
1435 * Returns the first requested ID.  This ID and next @n-1 IDs are now
1436 * valid IDs.  At least provided that @n is non-zero because if it
1437 * is, returns last requested ID which is now very useful information.
1438 *
1439 * @usb_string_ids_n() is called from bind() callbacks to allocate
1440 * string IDs.  Drivers for functions, configurations, or gadgets will
1441 * then store that ID in the appropriate descriptors and string table.
1442 *
1443 * All string identifier should be allocated using this,
1444 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1445 * example different functions don't wrongly assign different meanings
1446 * to the same identifier.
1447 */
1448int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1449{
1450        unsigned next = c->next_string_id;
1451        if (unlikely(n > 254 || (unsigned)next + n > 254))
1452                return -ENODEV;
1453        c->next_string_id += n;
1454        return next + 1;
1455}
1456EXPORT_SYMBOL_GPL(usb_string_ids_n);
1457
1458/*-------------------------------------------------------------------------*/
1459
1460static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1461{
1462        struct usb_composite_dev *cdev;
1463
1464        if (req->status || req->actual != req->length)
1465                DBG((struct usb_composite_dev *) ep->driver_data,
1466                                "setup complete --> %d, %d/%d\n",
1467                                req->status, req->actual, req->length);
1468
1469        /*
1470         * REVIST The same ep0 requests are shared with function drivers
1471         * so they don't have to maintain the same ->complete() stubs.
1472         *
1473         * Because of that, we need to check for the validity of ->context
1474         * here, even though we know we've set it to something useful.
1475         */
1476        if (!req->context)
1477                return;
1478
1479        cdev = req->context;
1480
1481        if (cdev->req == req)
1482                cdev->setup_pending = false;
1483        else if (cdev->os_desc_req == req)
1484                cdev->os_desc_pending = false;
1485        else
1486                WARN(1, "unknown request %p\n", req);
1487}
1488
1489static int composite_ep0_queue(struct usb_composite_dev *cdev,
1490                struct usb_request *req, gfp_t gfp_flags)
1491{
1492        int ret;
1493
1494        ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1495        if (ret == 0) {
1496                if (cdev->req == req)
1497                        cdev->setup_pending = true;
1498                else if (cdev->os_desc_req == req)
1499                        cdev->os_desc_pending = true;
1500                else
1501                        WARN(1, "unknown request %p\n", req);
1502        }
1503
1504        return ret;
1505}
1506
1507static int count_ext_compat(struct usb_configuration *c)
1508{
1509        int i, res;
1510
1511        res = 0;
1512        for (i = 0; i < c->next_interface_id; ++i) {
1513                struct usb_function *f;
1514                int j;
1515
1516                f = c->interface[i];
1517                for (j = 0; j < f->os_desc_n; ++j) {
1518                        struct usb_os_desc *d;
1519
1520                        if (i != f->os_desc_table[j].if_id)
1521                                continue;
1522                        d = f->os_desc_table[j].os_desc;
1523                        if (d && d->ext_compat_id)
1524                                ++res;
1525                }
1526        }
1527        BUG_ON(res > 255);
1528        return res;
1529}
1530
1531static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1532{
1533        int i, count;
1534
1535        count = 16;
1536        buf += 16;
1537        for (i = 0; i < c->next_interface_id; ++i) {
1538                struct usb_function *f;
1539                int j;
1540
1541                f = c->interface[i];
1542                for (j = 0; j < f->os_desc_n; ++j) {
1543                        struct usb_os_desc *d;
1544
1545                        if (i != f->os_desc_table[j].if_id)
1546                                continue;
1547                        d = f->os_desc_table[j].os_desc;
1548                        if (d && d->ext_compat_id) {
1549                                *buf++ = i;
1550                                *buf++ = 0x01;
1551                                memcpy(buf, d->ext_compat_id, 16);
1552                                buf += 22;
1553                        } else {
1554                                ++buf;
1555                                *buf = 0x01;
1556                                buf += 23;
1557                        }
1558                        count += 24;
1559                        if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1560                                return count;
1561                }
1562        }
1563
1564        return count;
1565}
1566
1567static int count_ext_prop(struct usb_configuration *c, int interface)
1568{
1569        struct usb_function *f;
1570        int j;
1571
1572        f = c->interface[interface];
1573        for (j = 0; j < f->os_desc_n; ++j) {
1574                struct usb_os_desc *d;
1575
1576                if (interface != f->os_desc_table[j].if_id)
1577                        continue;
1578                d = f->os_desc_table[j].os_desc;
1579                if (d && d->ext_compat_id)
1580                        return d->ext_prop_count;
1581        }
1582        return 0;
1583}
1584
1585static int len_ext_prop(struct usb_configuration *c, int interface)
1586{
1587        struct usb_function *f;
1588        struct usb_os_desc *d;
1589        int j, res;
1590
1591        res = 10; /* header length */
1592        f = c->interface[interface];
1593        for (j = 0; j < f->os_desc_n; ++j) {
1594                if (interface != f->os_desc_table[j].if_id)
1595                        continue;
1596                d = f->os_desc_table[j].os_desc;
1597                if (d)
1598                        return min(res + d->ext_prop_len, 4096);
1599        }
1600        return res;
1601}
1602
1603static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1604{
1605        struct usb_function *f;
1606        struct usb_os_desc *d;
1607        struct usb_os_desc_ext_prop *ext_prop;
1608        int j, count, n, ret;
1609
1610        f = c->interface[interface];
1611        count = 10; /* header length */
1612        buf += 10;
1613        for (j = 0; j < f->os_desc_n; ++j) {
1614                if (interface != f->os_desc_table[j].if_id)
1615                        continue;
1616                d = f->os_desc_table[j].os_desc;
1617                if (d)
1618                        list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1619                                n = ext_prop->data_len +
1620                                        ext_prop->name_len + 14;
1621                                if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1622                                        return count;
1623                                usb_ext_prop_put_size(buf, n);
1624                                usb_ext_prop_put_type(buf, ext_prop->type);
1625                                ret = usb_ext_prop_put_name(buf, ext_prop->name,
1626                                                            ext_prop->name_len);
1627                                if (ret < 0)
1628                                        return ret;
1629                                switch (ext_prop->type) {
1630                                case USB_EXT_PROP_UNICODE:
1631                                case USB_EXT_PROP_UNICODE_ENV:
1632                                case USB_EXT_PROP_UNICODE_LINK:
1633                                        usb_ext_prop_put_unicode(buf, ret,
1634                                                         ext_prop->data,
1635                                                         ext_prop->data_len);
1636                                        break;
1637                                case USB_EXT_PROP_BINARY:
1638                                        usb_ext_prop_put_binary(buf, ret,
1639                                                        ext_prop->data,
1640                                                        ext_prop->data_len);
1641                                        break;
1642                                case USB_EXT_PROP_LE32:
1643                                        /* not implemented */
1644                                case USB_EXT_PROP_BE32:
1645                                        /* not implemented */
1646                                default:
1647                                        return -EINVAL;
1648                                }
1649                                buf += n;
1650                                count += n;
1651                        }
1652        }
1653
1654        return count;
1655}
1656
1657/*
1658 * The setup() callback implements all the ep0 functionality that's
1659 * not handled lower down, in hardware or the hardware driver(like
1660 * device and endpoint feature flags, and their status).  It's all
1661 * housekeeping for the gadget function we're implementing.  Most of
1662 * the work is in config and function specific setup.
1663 */
1664int
1665composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1666{
1667        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1668        struct usb_request              *req = cdev->req;
1669        int                             value = -EOPNOTSUPP;
1670        int                             status = 0;
1671        u16                             w_index = le16_to_cpu(ctrl->wIndex);
1672        u8                              intf = w_index & 0xFF;
1673        u16                             w_value = le16_to_cpu(ctrl->wValue);
1674        u16                             w_length = le16_to_cpu(ctrl->wLength);
1675        struct usb_function             *f = NULL;
1676        u8                              endp;
1677
1678        /* partial re-init of the response message; the function or the
1679         * gadget might need to intercept e.g. a control-OUT completion
1680         * when we delegate to it.
1681         */
1682        req->zero = 0;
1683        req->context = cdev;
1684        req->complete = composite_setup_complete;
1685        req->length = 0;
1686        gadget->ep0->driver_data = cdev;
1687
1688        /*
1689         * Don't let non-standard requests match any of the cases below
1690         * by accident.
1691         */
1692        if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1693                goto unknown;
1694
1695        switch (ctrl->bRequest) {
1696
1697        /* we handle all standard USB descriptors */
1698        case USB_REQ_GET_DESCRIPTOR:
1699                if (ctrl->bRequestType != USB_DIR_IN)
1700                        goto unknown;
1701                switch (w_value >> 8) {
1702
1703                case USB_DT_DEVICE:
1704                        cdev->desc.bNumConfigurations =
1705                                count_configs(cdev, USB_DT_DEVICE);
1706                        cdev->desc.bMaxPacketSize0 =
1707                                cdev->gadget->ep0->maxpacket;
1708                        if (gadget_is_superspeed(gadget)) {
1709                                if (gadget->speed >= USB_SPEED_SUPER) {
1710                                        cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1711                                        cdev->desc.bMaxPacketSize0 = 9;
1712                                } else {
1713                                        cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1714                                }
1715                        } else {
1716                                if (gadget->lpm_capable)
1717                                        cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1718                                else
1719                                        cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1720                        }
1721
1722                        value = min(w_length, (u16) sizeof cdev->desc);
1723                        memcpy(req->buf, &cdev->desc, value);
1724                        break;
1725                case USB_DT_DEVICE_QUALIFIER:
1726                        if (!gadget_is_dualspeed(gadget) ||
1727                            gadget->speed >= USB_SPEED_SUPER)
1728                                break;
1729                        device_qual(cdev);
1730                        value = min_t(int, w_length,
1731                                sizeof(struct usb_qualifier_descriptor));
1732                        break;
1733                case USB_DT_OTHER_SPEED_CONFIG:
1734                        if (!gadget_is_dualspeed(gadget) ||
1735                            gadget->speed >= USB_SPEED_SUPER)
1736                                break;
1737                        fallthrough;
1738                case USB_DT_CONFIG:
1739                        value = config_desc(cdev, w_value);
1740                        if (value >= 0)
1741                                value = min(w_length, (u16) value);
1742                        break;
1743                case USB_DT_STRING:
1744                        value = get_string(cdev, req->buf,
1745                                        w_index, w_value & 0xff);
1746                        if (value >= 0)
1747                                value = min(w_length, (u16) value);
1748                        break;
1749                case USB_DT_BOS:
1750                        if (gadget_is_superspeed(gadget) ||
1751                            gadget->lpm_capable) {
1752                                value = bos_desc(cdev);
1753                                value = min(w_length, (u16) value);
1754                        }
1755                        break;
1756                case USB_DT_OTG:
1757                        if (gadget_is_otg(gadget)) {
1758                                struct usb_configuration *config;
1759                                int otg_desc_len = 0;
1760
1761                                if (cdev->config)
1762                                        config = cdev->config;
1763                                else
1764                                        config = list_first_entry(
1765                                                        &cdev->configs,
1766                                                struct usb_configuration, list);
1767                                if (!config)
1768                                        goto done;
1769
1770                                if (gadget->otg_caps &&
1771                                        (gadget->otg_caps->otg_rev >= 0x0200))
1772                                        otg_desc_len += sizeof(
1773                                                struct usb_otg20_descriptor);
1774                                else
1775                                        otg_desc_len += sizeof(
1776                                                struct usb_otg_descriptor);
1777
1778                                value = min_t(int, w_length, otg_desc_len);
1779                                memcpy(req->buf, config->descriptors[0], value);
1780                        }
1781                        break;
1782                }
1783                break;
1784
1785        /* any number of configs can work */
1786        case USB_REQ_SET_CONFIGURATION:
1787                if (ctrl->bRequestType != 0)
1788                        goto unknown;
1789                if (gadget_is_otg(gadget)) {
1790                        if (gadget->a_hnp_support)
1791                                DBG(cdev, "HNP available\n");
1792                        else if (gadget->a_alt_hnp_support)
1793                                DBG(cdev, "HNP on another port\n");
1794                        else
1795                                VDBG(cdev, "HNP inactive\n");
1796                }
1797                spin_lock(&cdev->lock);
1798                value = set_config(cdev, ctrl, w_value);
1799                spin_unlock(&cdev->lock);
1800                break;
1801        case USB_REQ_GET_CONFIGURATION:
1802                if (ctrl->bRequestType != USB_DIR_IN)
1803                        goto unknown;
1804                if (cdev->config)
1805                        *(u8 *)req->buf = cdev->config->bConfigurationValue;
1806                else
1807                        *(u8 *)req->buf = 0;
1808                value = min(w_length, (u16) 1);
1809                break;
1810
1811        /* function drivers must handle get/set altsetting */
1812        case USB_REQ_SET_INTERFACE:
1813                if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1814                        goto unknown;
1815                if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1816                        break;
1817                f = cdev->config->interface[intf];
1818                if (!f)
1819                        break;
1820
1821                /*
1822                 * If there's no get_alt() method, we know only altsetting zero
1823                 * works. There is no need to check if set_alt() is not NULL
1824                 * as we check this in usb_add_function().
1825                 */
1826                if (w_value && !f->get_alt)
1827                        break;
1828
1829                spin_lock(&cdev->lock);
1830                value = f->set_alt(f, w_index, w_value);
1831                if (value == USB_GADGET_DELAYED_STATUS) {
1832                        DBG(cdev,
1833                         "%s: interface %d (%s) requested delayed status\n",
1834                                        __func__, intf, f->name);
1835                        cdev->delayed_status++;
1836                        DBG(cdev, "delayed_status count %d\n",
1837                                        cdev->delayed_status);
1838                }
1839                spin_unlock(&cdev->lock);
1840                break;
1841        case USB_REQ_GET_INTERFACE:
1842                if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1843                        goto unknown;
1844                if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1845                        break;
1846                f = cdev->config->interface[intf];
1847                if (!f)
1848                        break;
1849                /* lots of interfaces only need altsetting zero... */
1850                value = f->get_alt ? f->get_alt(f, w_index) : 0;
1851                if (value < 0)
1852                        break;
1853                *((u8 *)req->buf) = value;
1854                value = min(w_length, (u16) 1);
1855                break;
1856        case USB_REQ_GET_STATUS:
1857                if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1858                                                (w_index == OTG_STS_SELECTOR)) {
1859                        if (ctrl->bRequestType != (USB_DIR_IN |
1860                                                        USB_RECIP_DEVICE))
1861                                goto unknown;
1862                        *((u8 *)req->buf) = gadget->host_request_flag;
1863                        value = 1;
1864                        break;
1865                }
1866
1867                /*
1868                 * USB 3.0 additions:
1869                 * Function driver should handle get_status request. If such cb
1870                 * wasn't supplied we respond with default value = 0
1871                 * Note: function driver should supply such cb only for the
1872                 * first interface of the function
1873                 */
1874                if (!gadget_is_superspeed(gadget))
1875                        goto unknown;
1876                if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1877                        goto unknown;
1878                value = 2;      /* This is the length of the get_status reply */
1879                put_unaligned_le16(0, req->buf);
1880                if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1881                        break;
1882                f = cdev->config->interface[intf];
1883                if (!f)
1884                        break;
1885                status = f->get_status ? f->get_status(f) : 0;
1886                if (status < 0)
1887                        break;
1888                put_unaligned_le16(status & 0x0000ffff, req->buf);
1889                break;
1890        /*
1891         * Function drivers should handle SetFeature/ClearFeature
1892         * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1893         * only for the first interface of the function
1894         */
1895        case USB_REQ_CLEAR_FEATURE:
1896        case USB_REQ_SET_FEATURE:
1897                if (!gadget_is_superspeed(gadget))
1898                        goto unknown;
1899                if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1900                        goto unknown;
1901                switch (w_value) {
1902                case USB_INTRF_FUNC_SUSPEND:
1903                        if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1904                                break;
1905                        f = cdev->config->interface[intf];
1906                        if (!f)
1907                                break;
1908                        value = 0;
1909                        if (f->func_suspend)
1910                                value = f->func_suspend(f, w_index >> 8);
1911                        if (value < 0) {
1912                                ERROR(cdev,
1913                                      "func_suspend() returned error %d\n",
1914                                      value);
1915                                value = 0;
1916                        }
1917                        break;
1918                }
1919                break;
1920        default:
1921unknown:
1922                /*
1923                 * OS descriptors handling
1924                 */
1925                if (cdev->use_os_string && cdev->os_desc_config &&
1926                    (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1927                    ctrl->bRequest == cdev->b_vendor_code) {
1928                        struct usb_configuration        *os_desc_cfg;
1929                        u8                              *buf;
1930                        int                             interface;
1931                        int                             count = 0;
1932
1933                        req = cdev->os_desc_req;
1934                        req->context = cdev;
1935                        req->complete = composite_setup_complete;
1936                        buf = req->buf;
1937                        os_desc_cfg = cdev->os_desc_config;
1938                        w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1939                        memset(buf, 0, w_length);
1940                        buf[5] = 0x01;
1941                        switch (ctrl->bRequestType & USB_RECIP_MASK) {
1942                        case USB_RECIP_DEVICE:
1943                                if (w_index != 0x4 || (w_value >> 8))
1944                                        break;
1945                                buf[6] = w_index;
1946                                /* Number of ext compat interfaces */
1947                                count = count_ext_compat(os_desc_cfg);
1948                                buf[8] = count;
1949                                count *= 24; /* 24 B/ext compat desc */
1950                                count += 16; /* header */
1951                                put_unaligned_le32(count, buf);
1952                                value = w_length;
1953                                if (w_length > 0x10) {
1954                                        value = fill_ext_compat(os_desc_cfg, buf);
1955                                        value = min_t(u16, w_length, value);
1956                                }
1957                                break;
1958                        case USB_RECIP_INTERFACE:
1959                                if (w_index != 0x5 || (w_value >> 8))
1960                                        break;
1961                                interface = w_value & 0xFF;
1962                                buf[6] = w_index;
1963                                count = count_ext_prop(os_desc_cfg,
1964                                        interface);
1965                                put_unaligned_le16(count, buf + 8);
1966                                count = len_ext_prop(os_desc_cfg,
1967                                        interface);
1968                                put_unaligned_le32(count, buf);
1969                                value = w_length;
1970                                if (w_length > 0x0A) {
1971                                        value = fill_ext_prop(os_desc_cfg,
1972                                                              interface, buf);
1973                                        if (value >= 0)
1974                                                value = min_t(u16, w_length, value);
1975                                }
1976                                break;
1977                        }
1978
1979                        goto check_value;
1980                }
1981
1982                VDBG(cdev,
1983                        "non-core control req%02x.%02x v%04x i%04x l%d\n",
1984                        ctrl->bRequestType, ctrl->bRequest,
1985                        w_value, w_index, w_length);
1986
1987                /* functions always handle their interfaces and endpoints...
1988                 * punt other recipients (other, WUSB, ...) to the current
1989                 * configuration code.
1990                 */
1991                if (cdev->config) {
1992                        list_for_each_entry(f, &cdev->config->functions, list)
1993                                if (f->req_match &&
1994                                    f->req_match(f, ctrl, false))
1995                                        goto try_fun_setup;
1996                } else {
1997                        struct usb_configuration *c;
1998                        list_for_each_entry(c, &cdev->configs, list)
1999                                list_for_each_entry(f, &c->functions, list)
2000                                        if (f->req_match &&
2001                                            f->req_match(f, ctrl, true))
2002                                                goto try_fun_setup;
2003                }
2004                f = NULL;
2005
2006                switch (ctrl->bRequestType & USB_RECIP_MASK) {
2007                case USB_RECIP_INTERFACE:
2008                        if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2009                                break;
2010                        f = cdev->config->interface[intf];
2011                        break;
2012
2013                case USB_RECIP_ENDPOINT:
2014                        if (!cdev->config)
2015                                break;
2016                        endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2017                        list_for_each_entry(f, &cdev->config->functions, list) {
2018                                if (test_bit(endp, f->endpoints))
2019                                        break;
2020                        }
2021                        if (&f->list == &cdev->config->functions)
2022                                f = NULL;
2023                        break;
2024                }
2025try_fun_setup:
2026                if (f && f->setup)
2027                        value = f->setup(f, ctrl);
2028                else {
2029                        struct usb_configuration        *c;
2030
2031                        c = cdev->config;
2032                        if (!c)
2033                                goto done;
2034
2035                        /* try current config's setup */
2036                        if (c->setup) {
2037                                value = c->setup(c, ctrl);
2038                                goto done;
2039                        }
2040
2041                        /* try the only function in the current config */
2042                        if (!list_is_singular(&c->functions))
2043                                goto done;
2044                        f = list_first_entry(&c->functions, struct usb_function,
2045                                             list);
2046                        if (f->setup)
2047                                value = f->setup(f, ctrl);
2048                }
2049
2050                goto done;
2051        }
2052
2053check_value:
2054        /* respond with data transfer before status phase? */
2055        if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2056                req->length = value;
2057                req->context = cdev;
2058                req->zero = value < w_length;
2059                value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2060                if (value < 0) {
2061                        DBG(cdev, "ep_queue --> %d\n", value);
2062                        req->status = 0;
2063                        composite_setup_complete(gadget->ep0, req);
2064                }
2065        } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2066                WARN(cdev,
2067                        "%s: Delayed status not supported for w_length != 0",
2068                        __func__);
2069        }
2070
2071done:
2072        /* device either stalls (value < 0) or reports success */
2073        return value;
2074}
2075
2076static void __composite_disconnect(struct usb_gadget *gadget)
2077{
2078        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2079        unsigned long                   flags;
2080
2081        /* REVISIT:  should we have config and device level
2082         * disconnect callbacks?
2083         */
2084        spin_lock_irqsave(&cdev->lock, flags);
2085        cdev->suspended = 0;
2086        if (cdev->config)
2087                reset_config(cdev);
2088        if (cdev->driver->disconnect)
2089                cdev->driver->disconnect(cdev);
2090        spin_unlock_irqrestore(&cdev->lock, flags);
2091}
2092
2093void composite_disconnect(struct usb_gadget *gadget)
2094{
2095        usb_gadget_vbus_draw(gadget, 0);
2096        __composite_disconnect(gadget);
2097}
2098
2099void composite_reset(struct usb_gadget *gadget)
2100{
2101        /*
2102         * Section 1.4.13 Standard Downstream Port of the USB battery charging
2103         * specification v1.2 states that a device connected on a SDP shall only
2104         * draw at max 100mA while in a connected, but unconfigured state.
2105         */
2106        usb_gadget_vbus_draw(gadget, 100);
2107        __composite_disconnect(gadget);
2108}
2109
2110/*-------------------------------------------------------------------------*/
2111
2112static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2113                              char *buf)
2114{
2115        struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2116        struct usb_composite_dev *cdev = get_gadget_data(gadget);
2117
2118        return sprintf(buf, "%d\n", cdev->suspended);
2119}
2120static DEVICE_ATTR_RO(suspended);
2121
2122static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2123{
2124        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2125        struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2126        struct usb_string               *dev_str = gstr->strings;
2127
2128        /* composite_disconnect() must already have been called
2129         * by the underlying peripheral controller driver!
2130         * so there's no i/o concurrency that could affect the
2131         * state protected by cdev->lock.
2132         */
2133        WARN_ON(cdev->config);
2134
2135        while (!list_empty(&cdev->configs)) {
2136                struct usb_configuration        *c;
2137                c = list_first_entry(&cdev->configs,
2138                                struct usb_configuration, list);
2139                remove_config(cdev, c);
2140        }
2141        if (cdev->driver->unbind && unbind_driver)
2142                cdev->driver->unbind(cdev);
2143
2144        composite_dev_cleanup(cdev);
2145
2146        if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2147                dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2148
2149        kfree(cdev->def_manufacturer);
2150        kfree(cdev);
2151        set_gadget_data(gadget, NULL);
2152}
2153
2154static void composite_unbind(struct usb_gadget *gadget)
2155{
2156        __composite_unbind(gadget, true);
2157}
2158
2159static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2160                const struct usb_device_descriptor *old)
2161{
2162        __le16 idVendor;
2163        __le16 idProduct;
2164        __le16 bcdDevice;
2165        u8 iSerialNumber;
2166        u8 iManufacturer;
2167        u8 iProduct;
2168
2169        /*
2170         * these variables may have been set in
2171         * usb_composite_overwrite_options()
2172         */
2173        idVendor = new->idVendor;
2174        idProduct = new->idProduct;
2175        bcdDevice = new->bcdDevice;
2176        iSerialNumber = new->iSerialNumber;
2177        iManufacturer = new->iManufacturer;
2178        iProduct = new->iProduct;
2179
2180        *new = *old;
2181        if (idVendor)
2182                new->idVendor = idVendor;
2183        if (idProduct)
2184                new->idProduct = idProduct;
2185        if (bcdDevice)
2186                new->bcdDevice = bcdDevice;
2187        else
2188                new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2189        if (iSerialNumber)
2190                new->iSerialNumber = iSerialNumber;
2191        if (iManufacturer)
2192                new->iManufacturer = iManufacturer;
2193        if (iProduct)
2194                new->iProduct = iProduct;
2195}
2196
2197int composite_dev_prepare(struct usb_composite_driver *composite,
2198                struct usb_composite_dev *cdev)
2199{
2200        struct usb_gadget *gadget = cdev->gadget;
2201        int ret = -ENOMEM;
2202
2203        /* preallocate control response and buffer */
2204        cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2205        if (!cdev->req)
2206                return -ENOMEM;
2207
2208        cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2209        if (!cdev->req->buf)
2210                goto fail;
2211
2212        ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2213        if (ret)
2214                goto fail_dev;
2215
2216        cdev->req->complete = composite_setup_complete;
2217        cdev->req->context = cdev;
2218        gadget->ep0->driver_data = cdev;
2219
2220        cdev->driver = composite;
2221
2222        /*
2223         * As per USB compliance update, a device that is actively drawing
2224         * more than 100mA from USB must report itself as bus-powered in
2225         * the GetStatus(DEVICE) call.
2226         */
2227        if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2228                usb_gadget_set_selfpowered(gadget);
2229
2230        /* interface and string IDs start at zero via kzalloc.
2231         * we force endpoints to start unassigned; few controller
2232         * drivers will zero ep->driver_data.
2233         */
2234        usb_ep_autoconfig_reset(gadget);
2235        return 0;
2236fail_dev:
2237        kfree(cdev->req->buf);
2238fail:
2239        usb_ep_free_request(gadget->ep0, cdev->req);
2240        cdev->req = NULL;
2241        return ret;
2242}
2243
2244int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2245                                  struct usb_ep *ep0)
2246{
2247        int ret = 0;
2248
2249        cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2250        if (!cdev->os_desc_req) {
2251                ret = -ENOMEM;
2252                goto end;
2253        }
2254
2255        cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2256                                         GFP_KERNEL);
2257        if (!cdev->os_desc_req->buf) {
2258                ret = -ENOMEM;
2259                usb_ep_free_request(ep0, cdev->os_desc_req);
2260                goto end;
2261        }
2262        cdev->os_desc_req->context = cdev;
2263        cdev->os_desc_req->complete = composite_setup_complete;
2264end:
2265        return ret;
2266}
2267
2268void composite_dev_cleanup(struct usb_composite_dev *cdev)
2269{
2270        struct usb_gadget_string_container *uc, *tmp;
2271        struct usb_ep                      *ep, *tmp_ep;
2272
2273        list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2274                list_del(&uc->list);
2275                kfree(uc);
2276        }
2277        if (cdev->os_desc_req) {
2278                if (cdev->os_desc_pending)
2279                        usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2280
2281                kfree(cdev->os_desc_req->buf);
2282                cdev->os_desc_req->buf = NULL;
2283                usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2284                cdev->os_desc_req = NULL;
2285        }
2286        if (cdev->req) {
2287                if (cdev->setup_pending)
2288                        usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2289
2290                kfree(cdev->req->buf);
2291                cdev->req->buf = NULL;
2292                usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2293                cdev->req = NULL;
2294        }
2295        cdev->next_string_id = 0;
2296        device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2297
2298        /*
2299         * Some UDC backends have a dynamic EP allocation scheme.
2300         *
2301         * In that case, the dispose() callback is used to notify the
2302         * backend that the EPs are no longer in use.
2303         *
2304         * Note: The UDC backend can remove the EP from the ep_list as
2305         *       a result, so we need to use the _safe list iterator.
2306         */
2307        list_for_each_entry_safe(ep, tmp_ep,
2308                                 &cdev->gadget->ep_list, ep_list) {
2309                if (ep->ops->dispose)
2310                        ep->ops->dispose(ep);
2311        }
2312}
2313
2314static int composite_bind(struct usb_gadget *gadget,
2315                struct usb_gadget_driver *gdriver)
2316{
2317        struct usb_composite_dev        *cdev;
2318        struct usb_composite_driver     *composite = to_cdriver(gdriver);
2319        int                             status = -ENOMEM;
2320
2321        cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2322        if (!cdev)
2323                return status;
2324
2325        spin_lock_init(&cdev->lock);
2326        cdev->gadget = gadget;
2327        set_gadget_data(gadget, cdev);
2328        INIT_LIST_HEAD(&cdev->configs);
2329        INIT_LIST_HEAD(&cdev->gstrings);
2330
2331        status = composite_dev_prepare(composite, cdev);
2332        if (status)
2333                goto fail;
2334
2335        /* composite gadget needs to assign strings for whole device (like
2336         * serial number), register function drivers, potentially update
2337         * power state and consumption, etc
2338         */
2339        status = composite->bind(cdev);
2340        if (status < 0)
2341                goto fail;
2342
2343        if (cdev->use_os_string) {
2344                status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2345                if (status)
2346                        goto fail;
2347        }
2348
2349        update_unchanged_dev_desc(&cdev->desc, composite->dev);
2350
2351        /* has userspace failed to provide a serial number? */
2352        if (composite->needs_serial && !cdev->desc.iSerialNumber)
2353                WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2354
2355        INFO(cdev, "%s ready\n", composite->name);
2356        return 0;
2357
2358fail:
2359        __composite_unbind(gadget, false);
2360        return status;
2361}
2362
2363/*-------------------------------------------------------------------------*/
2364
2365void composite_suspend(struct usb_gadget *gadget)
2366{
2367        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2368        struct usb_function             *f;
2369
2370        /* REVISIT:  should we have config level
2371         * suspend/resume callbacks?
2372         */
2373        DBG(cdev, "suspend\n");
2374        if (cdev->config) {
2375                list_for_each_entry(f, &cdev->config->functions, list) {
2376                        if (f->suspend)
2377                                f->suspend(f);
2378                }
2379        }
2380        if (cdev->driver->suspend)
2381                cdev->driver->suspend(cdev);
2382
2383        cdev->suspended = 1;
2384
2385        usb_gadget_set_selfpowered(gadget);
2386        usb_gadget_vbus_draw(gadget, 2);
2387}
2388
2389void composite_resume(struct usb_gadget *gadget)
2390{
2391        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2392        struct usb_function             *f;
2393        unsigned                        maxpower;
2394
2395        /* REVISIT:  should we have config level
2396         * suspend/resume callbacks?
2397         */
2398        DBG(cdev, "resume\n");
2399        if (cdev->driver->resume)
2400                cdev->driver->resume(cdev);
2401        if (cdev->config) {
2402                list_for_each_entry(f, &cdev->config->functions, list) {
2403                        if (f->resume)
2404                                f->resume(f);
2405                }
2406
2407                maxpower = cdev->config->MaxPower ?
2408                        cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2409                if (gadget->speed < USB_SPEED_SUPER)
2410                        maxpower = min(maxpower, 500U);
2411                else
2412                        maxpower = min(maxpower, 900U);
2413
2414                if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2415                        usb_gadget_clear_selfpowered(gadget);
2416
2417                usb_gadget_vbus_draw(gadget, maxpower);
2418        }
2419
2420        cdev->suspended = 0;
2421}
2422
2423/*-------------------------------------------------------------------------*/
2424
2425static const struct usb_gadget_driver composite_driver_template = {
2426        .bind           = composite_bind,
2427        .unbind         = composite_unbind,
2428
2429        .setup          = composite_setup,
2430        .reset          = composite_reset,
2431        .disconnect     = composite_disconnect,
2432
2433        .suspend        = composite_suspend,
2434        .resume         = composite_resume,
2435
2436        .driver = {
2437                .owner          = THIS_MODULE,
2438        },
2439};
2440
2441/**
2442 * usb_composite_probe() - register a composite driver
2443 * @driver: the driver to register
2444 *
2445 * Context: single threaded during gadget setup
2446 *
2447 * This function is used to register drivers using the composite driver
2448 * framework.  The return value is zero, or a negative errno value.
2449 * Those values normally come from the driver's @bind method, which does
2450 * all the work of setting up the driver to match the hardware.
2451 *
2452 * On successful return, the gadget is ready to respond to requests from
2453 * the host, unless one of its components invokes usb_gadget_disconnect()
2454 * while it was binding.  That would usually be done in order to wait for
2455 * some userspace participation.
2456 */
2457int usb_composite_probe(struct usb_composite_driver *driver)
2458{
2459        struct usb_gadget_driver *gadget_driver;
2460
2461        if (!driver || !driver->dev || !driver->bind)
2462                return -EINVAL;
2463
2464        if (!driver->name)
2465                driver->name = "composite";
2466
2467        driver->gadget_driver = composite_driver_template;
2468        gadget_driver = &driver->gadget_driver;
2469
2470        gadget_driver->function =  (char *) driver->name;
2471        gadget_driver->driver.name = driver->name;
2472        gadget_driver->max_speed = driver->max_speed;
2473
2474        return usb_gadget_probe_driver(gadget_driver);
2475}
2476EXPORT_SYMBOL_GPL(usb_composite_probe);
2477
2478/**
2479 * usb_composite_unregister() - unregister a composite driver
2480 * @driver: the driver to unregister
2481 *
2482 * This function is used to unregister drivers using the composite
2483 * driver framework.
2484 */
2485void usb_composite_unregister(struct usb_composite_driver *driver)
2486{
2487        usb_gadget_unregister_driver(&driver->gadget_driver);
2488}
2489EXPORT_SYMBOL_GPL(usb_composite_unregister);
2490
2491/**
2492 * usb_composite_setup_continue() - Continue with the control transfer
2493 * @cdev: the composite device who's control transfer was kept waiting
2494 *
2495 * This function must be called by the USB function driver to continue
2496 * with the control transfer's data/status stage in case it had requested to
2497 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2498 * can request the composite framework to delay the setup request's data/status
2499 * stages by returning USB_GADGET_DELAYED_STATUS.
2500 */
2501void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2502{
2503        int                     value;
2504        struct usb_request      *req = cdev->req;
2505        unsigned long           flags;
2506
2507        DBG(cdev, "%s\n", __func__);
2508        spin_lock_irqsave(&cdev->lock, flags);
2509
2510        if (cdev->delayed_status == 0) {
2511                WARN(cdev, "%s: Unexpected call\n", __func__);
2512
2513        } else if (--cdev->delayed_status == 0) {
2514                DBG(cdev, "%s: Completing delayed status\n", __func__);
2515                req->length = 0;
2516                req->context = cdev;
2517                value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2518                if (value < 0) {
2519                        DBG(cdev, "ep_queue --> %d\n", value);
2520                        req->status = 0;
2521                        composite_setup_complete(cdev->gadget->ep0, req);
2522                }
2523        }
2524
2525        spin_unlock_irqrestore(&cdev->lock, flags);
2526}
2527EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2528
2529static char *composite_default_mfr(struct usb_gadget *gadget)
2530{
2531        return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2532                         init_utsname()->release, gadget->name);
2533}
2534
2535void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2536                struct usb_composite_overwrite *covr)
2537{
2538        struct usb_device_descriptor    *desc = &cdev->desc;
2539        struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2540        struct usb_string               *dev_str = gstr->strings;
2541
2542        if (covr->idVendor)
2543                desc->idVendor = cpu_to_le16(covr->idVendor);
2544
2545        if (covr->idProduct)
2546                desc->idProduct = cpu_to_le16(covr->idProduct);
2547
2548        if (covr->bcdDevice)
2549                desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2550
2551        if (covr->serial_number) {
2552                desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2553                dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2554        }
2555        if (covr->manufacturer) {
2556                desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2557                dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2558
2559        } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2560                desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2561                cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2562                dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2563        }
2564
2565        if (covr->product) {
2566                desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2567                dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2568        }
2569}
2570EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2571
2572MODULE_LICENSE("GPL");
2573MODULE_AUTHOR("David Brownell");
2574