drivers/usb/gadget/composite.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * composite.c - infrastructure for Composite USB Gadgets
   4  *
   5  * Copyright (C) 2006-2008 David Brownell
   6  */
   7
   8 /* #define VERBOSE_DEBUG */
   9
  10 #include <linux/kallsyms.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14 #include <linux/device.h>
  15 #include <linux/utsname.h>
  16
  17 #include <linux/usb/composite.h>
  18 #include <linux/usb/otg.h>
  19 #include <asm/unaligned.h>
  20
  21 #include "u_os_desc.h"
  22
  23 /**
  24  * struct usb_os_string - represents OS String to be reported by a gadget
  25  * @bLength: total length of the entire descritor, always 0x12
  26  * @bDescriptorType: USB_DT_STRING
  27  * @qwSignature: the OS String proper
  28  * @bMS_VendorCode: code used by the host for subsequent requests
  29  * @bPad: not used, must be zero
  30  */
  31 struct usb_os_string {
  32         __u8    bLength;
  33         __u8    bDescriptorType;
  34         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  35         __u8    bMS_VendorCode;
  36         __u8    bPad;
  37 } __packed;
  38
  39 /*
  40  * The code in this file is utility code, used to build a gadget driver
  41  * from one or more "function" drivers, one or more "configuration"
  42  * objects, and a "usb_composite_driver" by gluing them together along
  43  * with the relevant device-wide data.
  44  */
  45
  46 static struct usb_gadget_strings **get_containers_gs(
  47                 struct usb_gadget_string_container *uc)
  48 {
  49         return (struct usb_gadget_strings **)uc->stash;
  50 }
  51
  52 /**
  53  * function_descriptors() - get function descriptors for speed
  54  * @f: the function
  55  * @speed: the speed
  56  *
  57  * Returns the descriptors or NULL if not set.
  58  */
  59 static struct usb_descriptor_header **
  60 function_descriptors(struct usb_function *f,
  61                      enum usb_device_speed speed)
  62 {
  63         struct usb_descriptor_header **descriptors;
  64
  65         /*
  66          * NOTE: we try to help gadget drivers which might not be setting
  67          * max_speed appropriately.
  68          */
  69
  70         switch (speed) {
  71         case USB_SPEED_SUPER_PLUS:
  72                 descriptors = f->ssp_descriptors;
  73                 if (descriptors)
  74                         break;
  75                 /* FALLTHROUGH */
  76         case USB_SPEED_SUPER:
  77                 descriptors = f->ss_descriptors;
  78                 if (descriptors)
  79                         break;
  80                 /* FALLTHROUGH */
  81         case USB_SPEED_HIGH:
  82                 descriptors = f->hs_descriptors;
  83                 if (descriptors)
  84                         break;
  85                 /* FALLTHROUGH */
  86         default:
  87                 descriptors = f->fs_descriptors;
  88         }
  89
  90         /*
  91          * if we can't find any descriptors at all, then this gadget deserves to
  92          * Oops with a NULL pointer dereference
  93          */
  94
  95         return descriptors;
  96 }
  97
  98 /**
  99  * next_ep_desc() - advance to the next EP descriptor
 100  * @t: currect pointer within descriptor array
 101  *
 102  * Return: next EP descriptor or NULL
 103  *
 104  * Iterate over @t until either EP descriptor found or
 105  * NULL (that indicates end of list) encountered
 106  */
 107 static struct usb_descriptor_header**
 108 next_ep_desc(struct usb_descriptor_header **t)
 109 {
 110         for (; *t; t++) {
 111                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
 112                         return t;
 113         }
 114         return NULL;
 115 }
 116
 117 /*
 118  * for_each_ep_desc()- iterate over endpoint descriptors in the
 119  *              descriptors list
 120  * @start:      pointer within descriptor array.
 121  * @ep_desc:    endpoint descriptor to use as the loop cursor
 122  */
 123 #define for_each_ep_desc(start, ep_desc) \
 124         for (ep_desc = next_ep_desc(start); \
 125               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
 126
 127 /**
 128  * config_ep_by_speed() - configures the given endpoint
 129  * according to gadget speed.
 130  * @g: pointer to the gadget
 131  * @f: usb function
 132  * @_ep: the endpoint to configure
 133  *
 134  * Return: error code, 0 on success
 135  *
 136  * This function chooses the right descriptors for a given
 137  * endpoint according to gadget speed and saves it in the
 138  * endpoint desc field. If the endpoint already has a descriptor
 139  * assigned to it - overwrites it with currently corresponding
 140  * descriptor. The endpoint maxpacket field is updated according
 141  * to the chosen descriptor.
 142  * Note: the supplied function should hold all the descriptors
 143  * for supported speeds
 144  */
 145 int config_ep_by_speed(struct usb_gadget *g,
 146                         struct usb_function *f,
 147                         struct usb_ep *_ep)
 148 {
 149         struct usb_endpoint_descriptor *chosen_desc = NULL;
 150         struct usb_descriptor_header **speed_desc = NULL;
 151
 152         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 153         int want_comp_desc = 0;
 154
 155         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 156
 157         if (!g || !f || !_ep)
 158                 return -EIO;
 159
 160         /* select desired speed */
 161         switch (g->speed) {
 162         case USB_SPEED_SUPER_PLUS:
 163                 if (gadget_is_superspeed_plus(g)) {
 164                         speed_desc = f->ssp_descriptors;
 165                         want_comp_desc = 1;
 166                         break;
 167                 }
 168                 /* fall through */
 169         case USB_SPEED_SUPER:
 170                 if (gadget_is_superspeed(g)) {
 171                         speed_desc = f->ss_descriptors;
 172                         want_comp_desc = 1;
 173                         break;
 174                 }
 175                 /* fall through */
 176         case USB_SPEED_HIGH:
 177                 if (gadget_is_dualspeed(g)) {
 178                         speed_desc = f->hs_descriptors;
 179                         break;
 180                 }
 181                 /* fall through */
 182         default:
 183                 speed_desc = f->fs_descriptors;
 184         }
 185         /* find descriptors */
 186         for_each_ep_desc(speed_desc, d_spd) {
 187                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 188                 if (chosen_desc->bEndpointAddress == _ep->address)
 189                         goto ep_found;
 190         }
 191         return -EIO;
 192
 193 ep_found:
 194         /* commit results */
 195         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 196         _ep->desc = chosen_desc;
 197         _ep->comp_desc = NULL;
 198         _ep->maxburst = 0;
 199         _ep->mult = 1;
 200
 201         if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 202                                 usb_endpoint_xfer_int(_ep->desc)))
 203                 _ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 204
 205         if (!want_comp_desc)
 206                 return 0;
 207
 208         /*
 209          * Companion descriptor should follow EP descriptor
 210          * USB 3.0 spec, #9.6.7
 211          */
 212         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 213         if (!comp_desc ||
 214             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 215                 return -EIO;
 216         _ep->comp_desc = comp_desc;
 217         if (g->speed >= USB_SPEED_SUPER) {
 218                 switch (usb_endpoint_type(_ep->desc)) {
 219                 case USB_ENDPOINT_XFER_ISOC:
 220                         /* mult: bits 1:0 of bmAttributes */
 221                         _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 222                         /* fall through */
 223                 case USB_ENDPOINT_XFER_BULK:
 224                 case USB_ENDPOINT_XFER_INT:
 225                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 226                         break;
 227                 default:
 228                         if (comp_desc->bMaxBurst != 0) {
 229                                 struct usb_composite_dev *cdev;
 230
 231                                 cdev = get_gadget_data(g);
 232                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 233                         }
 234                         _ep->maxburst = 1;
 235                         break;
 236                 }
 237         }
 238         return 0;
 239 }
 240 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 241
 242 /**
 243  * usb_add_function() - add a function to a configuration
 244  * @config: the configuration
 245  * @function: the function being added
 246  * Context: single threaded during gadget setup
 247  *
 248  * After initialization, each configuration must have one or more
 249  * functions added to it.  Adding a function involves calling its @bind()
 250  * method to allocate resources such as interface and string identifiers
 251  * and endpoints.
 252  *
 253  * This function returns the value of the function's bind(), which is
 254  * zero for success else a negative errno value.
 255  */
 256 int usb_add_function(struct usb_configuration *config,
 257                 struct usb_function *function)
 258 {
 259         int     value = -EINVAL;
 260
 261         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 262                         function->name, function,
 263                         config->label, config);
 264
 265         if (!function->set_alt || !function->disable)
 266                 goto done;
 267
 268         function->config = config;
 269         list_add_tail(&function->list, &config->functions);
 270
 271         if (function->bind_deactivated) {
 272                 value = usb_function_deactivate(function);
 273                 if (value)
 274                         goto done;
 275         }
 276
 277         /* REVISIT *require* function->bind? */
 278         if (function->bind) {
 279                 value = function->bind(config, function);
 280                 if (value < 0) {
 281                         list_del(&function->list);
 282                         function->config = NULL;
 283                 }
 284         } else
 285                 value = 0;
 286
 287         /* We allow configurations that don't work at both speeds.
 288          * If we run into a lowspeed Linux system, treat it the same
 289          * as full speed ... it's the function drivers that will need
 290          * to avoid bulk and ISO transfers.
 291          */
 292         if (!config->fullspeed && function->fs_descriptors)
 293                 config->fullspeed = true;
 294         if (!config->highspeed && function->hs_descriptors)
 295                 config->highspeed = true;
 296         if (!config->superspeed && function->ss_descriptors)
 297                 config->superspeed = true;
 298         if (!config->superspeed_plus && function->ssp_descriptors)
 299                 config->superspeed_plus = true;
 300
 301 done:
 302         if (value)
 303                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 304                                 function->name, function, value);
 305         return value;
 306 }
 307 EXPORT_SYMBOL_GPL(usb_add_function);
 308
 309 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 310 {
 311         if (f->disable)
 312                 f->disable(f);
 313
 314         bitmap_zero(f->endpoints, 32);
 315         list_del(&f->list);
 316         if (f->unbind)
 317                 f->unbind(c, f);
 318
 319         if (f->bind_deactivated)
 320                 usb_function_activate(f);
 321 }
 322 EXPORT_SYMBOL_GPL(usb_remove_function);
 323
 324 /**
 325  * usb_function_deactivate - prevent function and gadget enumeration
 326  * @function: the function that isn't yet ready to respond
 327  *
 328  * Blocks response of the gadget driver to host enumeration by
 329  * preventing the data line pullup from being activated.  This is
 330  * normally called during @bind() processing to change from the
 331  * initial "ready to respond" state, or when a required resource
 332  * becomes available.
 333  *
 334  * For example, drivers that serve as a passthrough to a userspace
 335  * daemon can block enumeration unless that daemon (such as an OBEX,
 336  * MTP, or print server) is ready to handle host requests.
 337  *
 338  * Not all systems support software control of their USB peripheral
 339  * data pullups.
 340  *
 341  * Returns zero on success, else negative errno.
 342  */
 343 int usb_function_deactivate(struct usb_function *function)
 344 {
 345         struct usb_composite_dev        *cdev = function->config->cdev;
 346         unsigned long                   flags;
 347         int                             status = 0;
 348
 349         spin_lock_irqsave(&cdev->lock, flags);
 350
 351         if (cdev->deactivations == 0)
 352                 status = usb_gadget_deactivate(cdev->gadget);
 353         if (status == 0)
 354                 cdev->deactivations++;
 355
 356         spin_unlock_irqrestore(&cdev->lock, flags);
 357         return status;
 358 }
 359 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 360
 361 /**
 362  * usb_function_activate - allow function and gadget enumeration
 363  * @function: function on which usb_function_activate() was called
 364  *
 365  * Reverses effect of usb_function_deactivate().  If no more functions
 366  * are delaying their activation, the gadget driver will respond to
 367  * host enumeration procedures.
 368  *
 369  * Returns zero on success, else negative errno.
 370  */
 371 int usb_function_activate(struct usb_function *function)
 372 {
 373         struct usb_composite_dev        *cdev = function->config->cdev;
 374         unsigned long                   flags;
 375         int                             status = 0;
 376
 377         spin_lock_irqsave(&cdev->lock, flags);
 378
 379         if (WARN_ON(cdev->deactivations == 0))
 380                 status = -EINVAL;
 381         else {
 382                 cdev->deactivations--;
 383                 if (cdev->deactivations == 0)
 384                         status = usb_gadget_activate(cdev->gadget);
 385         }
 386
 387         spin_unlock_irqrestore(&cdev->lock, flags);
 388         return status;
 389 }
 390 EXPORT_SYMBOL_GPL(usb_function_activate);
 391
 392 /**
 393  * usb_interface_id() - allocate an unused interface ID
 394  * @config: configuration associated with the interface
 395  * @function: function handling the interface
 396  * Context: single threaded during gadget setup
 397  *
 398  * usb_interface_id() is called from usb_function.bind() callbacks to
 399  * allocate new interface IDs.  The function driver will then store that
 400  * ID in interface, association, CDC union, and other descriptors.  It
 401  * will also handle any control requests targeted at that interface,
 402  * particularly changing its altsetting via set_alt().  There may
 403  * also be class-specific or vendor-specific requests to handle.
 404  *
 405  * All interface identifier should be allocated using this routine, to
 406  * ensure that for example different functions don't wrongly assign
 407  * different meanings to the same identifier.  Note that since interface
 408  * identifiers are configuration-specific, functions used in more than
 409  * one configuration (or more than once in a given configuration) need
 410  * multiple versions of the relevant descriptors.
 411  *
 412  * Returns the interface ID which was allocated; or -ENODEV if no
 413  * more interface IDs can be allocated.
 414  */
 415 int usb_interface_id(struct usb_configuration *config,
 416                 struct usb_function *function)
 417 {
 418         unsigned id = config->next_interface_id;
 419
 420         if (id < MAX_CONFIG_INTERFACES) {
 421                 config->interface[id] = function;
 422                 config->next_interface_id = id + 1;
 423                 return id;
 424         }
 425         return -ENODEV;
 426 }
 427 EXPORT_SYMBOL_GPL(usb_interface_id);
 428
 429 static u8 encode_bMaxPower(enum usb_device_speed speed,
 430                 struct usb_configuration *c)
 431 {
 432         unsigned val;
 433
 434         if (c->MaxPower)
 435                 val = c->MaxPower;
 436         else
 437                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 438         if (!val)
 439                 return 0;
 440         if (speed < USB_SPEED_SUPER)
 441                 return min(val, 500U) / 2;
 442         else
 443                 /*
 444                  * USB 3.x supports up to 900mA, but since 900 isn't divisible
 445                  * by 8 the integral division will effectively cap to 896mA.
 446                  */
 447                 return min(val, 900U) / 8;
 448 }
 449
 450 static int config_buf(struct usb_configuration *config,
 451                 enum usb_device_speed speed, void *buf, u8 type)
 452 {
 453         struct usb_config_descriptor    *c = buf;
 454         void                            *next = buf + USB_DT_CONFIG_SIZE;
 455         int                             len;
 456         struct usb_function             *f;
 457         int                             status;
 458
 459         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 460         /* write the config descriptor */
 461         c = buf;
 462         c->bLength = USB_DT_CONFIG_SIZE;
 463         c->bDescriptorType = type;
 464         /* wTotalLength is written later */
 465         c->bNumInterfaces = config->next_interface_id;
 466         c->bConfigurationValue = config->bConfigurationValue;
 467         c->iConfiguration = config->iConfiguration;
 468         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 469         c->bMaxPower = encode_bMaxPower(speed, config);
 470
 471         /* There may be e.g. OTG descriptors */
 472         if (config->descriptors) {
 473                 status = usb_descriptor_fillbuf(next, len,
 474                                 config->descriptors);
 475                 if (status < 0)
 476                         return status;
 477                 len -= status;
 478                 next += status;
 479         }
 480
 481         /* add each function's descriptors */
 482         list_for_each_entry(f, &config->functions, list) {
 483                 struct usb_descriptor_header **descriptors;
 484
 485                 descriptors = function_descriptors(f, speed);
 486                 if (!descriptors)
 487                         continue;
 488                 status = usb_descriptor_fillbuf(next, len,
 489                         (const struct usb_descriptor_header **) descriptors);
 490                 if (status < 0)
 491                         return status;
 492                 len -= status;
 493                 next += status;
 494         }
 495
 496         len = next - buf;
 497         c->wTotalLength = cpu_to_le16(len);
 498         return len;
 499 }
 500
 501 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 502 {
 503         struct usb_gadget               *gadget = cdev->gadget;
 504         struct usb_configuration        *c;
 505         struct list_head                *pos;
 506         u8                              type = w_value >> 8;
 507         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 508
 509         if (gadget->speed >= USB_SPEED_SUPER)
 510                 speed = gadget->speed;
 511         else if (gadget_is_dualspeed(gadget)) {
 512                 int     hs = 0;
 513                 if (gadget->speed == USB_SPEED_HIGH)
 514                         hs = 1;
 515                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 516                         hs = !hs;
 517                 if (hs)
 518                         speed = USB_SPEED_HIGH;
 519
 520         }
 521
 522         /* This is a lookup by config *INDEX* */
 523         w_value &= 0xff;
 524
 525         pos = &cdev->configs;
 526         c = cdev->os_desc_config;
 527         if (c)
 528                 goto check_config;
 529
 530         while ((pos = pos->next) !=  &cdev->configs) {
 531                 c = list_entry(pos, typeof(*c), list);
 532
 533                 /* skip OS Descriptors config which is handled separately */
 534                 if (c == cdev->os_desc_config)
 535                         continue;
 536
 537 check_config:
 538                 /* ignore configs that won't work at this speed */
 539                 switch (speed) {
 540                 case USB_SPEED_SUPER_PLUS:
 541                         if (!c->superspeed_plus)
 542                                 continue;
 543                         break;
 544                 case USB_SPEED_SUPER:
 545                         if (!c->superspeed)
 546                                 continue;
 547                         break;
 548                 case USB_SPEED_HIGH:
 549                         if (!c->highspeed)
 550                                 continue;
 551                         break;
 552                 default:
 553                         if (!c->fullspeed)
 554                                 continue;
 555                 }
 556
 557                 if (w_value == 0)
 558                         return config_buf(c, speed, cdev->req->buf, type);
 559                 w_value--;
 560         }
 561         return -EINVAL;
 562 }
 563
 564 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 565 {
 566         struct usb_gadget               *gadget = cdev->gadget;
 567         struct usb_configuration        *c;
 568         unsigned                        count = 0;
 569         int                             hs = 0;
 570         int                             ss = 0;
 571         int                             ssp = 0;
 572
 573         if (gadget_is_dualspeed(gadget)) {
 574                 if (gadget->speed == USB_SPEED_HIGH)
 575                         hs = 1;
 576                 if (gadget->speed == USB_SPEED_SUPER)
 577                         ss = 1;
 578                 if (gadget->speed == USB_SPEED_SUPER_PLUS)
 579                         ssp = 1;
 580                 if (type == USB_DT_DEVICE_QUALIFIER)
 581                         hs = !hs;
 582         }
 583         list_for_each_entry(c, &cdev->configs, list) {
 584                 /* ignore configs that won't work at this speed */
 585                 if (ssp) {
 586                         if (!c->superspeed_plus)
 587                                 continue;
 588                 } else if (ss) {
 589                         if (!c->superspeed)
 590                                 continue;
 591                 } else if (hs) {
 592                         if (!c->highspeed)
 593                                 continue;
 594                 } else {
 595                         if (!c->fullspeed)
 596                                 continue;
 597                 }
 598                 count++;
 599         }
 600         return count;
 601 }
 602
 603 /**
 604  * bos_desc() - prepares the BOS descriptor.
 605  * @cdev: pointer to usb_composite device to generate the bos
 606  *      descriptor for
 607  *
 608  * This function generates the BOS (Binary Device Object)
 609  * descriptor and its device capabilities descriptors. The BOS
 610  * descriptor should be supported by a SuperSpeed device.
 611  */
 612 static int bos_desc(struct usb_composite_dev *cdev)
 613 {
 614         struct usb_ext_cap_descriptor   *usb_ext;
 615         struct usb_dcd_config_params    dcd_config_params;
 616         struct usb_bos_descriptor       *bos = cdev->req->buf;
 617         unsigned int                    besl = 0;
 618
 619         bos->bLength = USB_DT_BOS_SIZE;
 620         bos->bDescriptorType = USB_DT_BOS;
 621
 622         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 623         bos->bNumDeviceCaps = 0;
 624
 625         /* Get Controller configuration */
 626         if (cdev->gadget->ops->get_config_params) {
 627                 cdev->gadget->ops->get_config_params(cdev->gadget,
 628                                                      &dcd_config_params);
 629         } else {
 630                 dcd_config_params.besl_baseline =
 631                         USB_DEFAULT_BESL_UNSPECIFIED;
 632                 dcd_config_params.besl_deep =
 633                         USB_DEFAULT_BESL_UNSPECIFIED;
 634                 dcd_config_params.bU1devExitLat =
 635                         USB_DEFAULT_U1_DEV_EXIT_LAT;
 636                 dcd_config_params.bU2DevExitLat =
 637                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 638         }
 639
 640         if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
 641                 besl = USB_BESL_BASELINE_VALID |
 642                         USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
 643
 644         if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
 645                 besl |= USB_BESL_DEEP_VALID |
 646                         USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
 647
 648         /*
 649          * A SuperSpeed device shall include the USB2.0 extension descriptor
 650          * and shall support LPM when operating in USB2.0 HS mode.
 651          */
 652         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 653         bos->bNumDeviceCaps++;
 654         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 655         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 656         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 657         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 658         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
 659                                             USB_BESL_SUPPORT | besl);
 660
 661         /*
 662          * The Superspeed USB Capability descriptor shall be implemented by all
 663          * SuperSpeed devices.
 664          */
 665         if (gadget_is_superspeed(cdev->gadget)) {
 666                 struct usb_ss_cap_descriptor *ss_cap;
 667
 668                 ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 669                 bos->bNumDeviceCaps++;
 670                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 671                 ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 672                 ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 673                 ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 674                 ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 675                 ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 676                                                       USB_FULL_SPEED_OPERATION |
 677                                                       USB_HIGH_SPEED_OPERATION |
 678                                                       USB_5GBPS_OPERATION);
 679                 ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 680                 ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 681                 ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 682         }
 683
 684         /* The SuperSpeedPlus USB Device Capability descriptor */
 685         if (gadget_is_superspeed_plus(cdev->gadget)) {
 686                 struct usb_ssp_cap_descriptor *ssp_cap;
 687
 688                 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 689                 bos->bNumDeviceCaps++;
 690
 691                 /*
 692                  * Report typical values.
 693                  */
 694
 695                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
 696                 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
 697                 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 698                 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 699                 ssp_cap->bReserved = 0;
 700                 ssp_cap->wReserved = 0;
 701
 702                 /* SSAC = 1 (2 attributes) */
 703                 ssp_cap->bmAttributes = cpu_to_le32(1);
 704
 705                 /* Min RX/TX Lane Count = 1 */
 706                 ssp_cap->wFunctionalitySupport =
 707                         cpu_to_le16((1 << 8) | (1 << 12));
 708
 709                 /*
 710                  * bmSublinkSpeedAttr[0]:
 711                  *   ST  = Symmetric, RX
 712                  *   LSE =  3 (Gbps)
 713                  *   LP  =  1 (SuperSpeedPlus)
 714                  *   LSM = 10 (10 Gbps)
 715                  */
 716                 ssp_cap->bmSublinkSpeedAttr[0] =
 717                         cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
 718                 /*
 719                  * bmSublinkSpeedAttr[1] =
 720                  *   ST  = Symmetric, TX
 721                  *   LSE =  3 (Gbps)
 722                  *   LP  =  1 (SuperSpeedPlus)
 723                  *   LSM = 10 (10 Gbps)
 724                  */
 725                 ssp_cap->bmSublinkSpeedAttr[1] =
 726                         cpu_to_le32((3 << 4) | (1 << 14) |
 727                                     (0xa << 16) | (1 << 7));
 728         }
 729
 730         return le16_to_cpu(bos->wTotalLength);
 731 }
 732
 733 static void device_qual(struct usb_composite_dev *cdev)
 734 {
 735         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 736
 737         qual->bLength = sizeof(*qual);
 738         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 739         /* POLICY: same bcdUSB and device type info at both speeds */
 740         qual->bcdUSB = cdev->desc.bcdUSB;
 741         qual->bDeviceClass = cdev->desc.bDeviceClass;
 742         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 743         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 744         /* ASSUME same EP0 fifo size at both speeds */
 745         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 746         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 747         qual->bRESERVED = 0;
 748 }
 749
 750 /*-------------------------------------------------------------------------*/
 751
 752 static void reset_config(struct usb_composite_dev *cdev)
 753 {
 754         struct usb_function             *f;
 755
 756         DBG(cdev, "reset config\n");
 757
 758         list_for_each_entry(f, &cdev->config->functions, list) {
 759                 if (f->disable)
 760                         f->disable(f);
 761
 762                 bitmap_zero(f->endpoints, 32);
 763         }
 764         cdev->config = NULL;
 765         cdev->delayed_status = 0;
 766 }
 767
 768 static int set_config(struct usb_composite_dev *cdev,
 769                 const struct usb_ctrlrequest *ctrl, unsigned number)
 770 {
 771         struct usb_gadget       *gadget = cdev->gadget;
 772         struct usb_configuration *c = NULL;
 773         int                     result = -EINVAL;
 774         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 775         int                     tmp;
 776
 777         if (number) {
 778                 list_for_each_entry(c, &cdev->configs, list) {
 779                         if (c->bConfigurationValue == number) {
 780                                 /*
 781                                  * We disable the FDs of the previous
 782                                  * configuration only if the new configuration
 783                                  * is a valid one
 784                                  */
 785                                 if (cdev->config)
 786                                         reset_config(cdev);
 787                                 result = 0;
 788                                 break;
 789                         }
 790                 }
 791                 if (result < 0)
 792                         goto done;
 793         } else { /* Zero configuration value - need to reset the config */
 794                 if (cdev->config)
 795                         reset_config(cdev);
 796                 result = 0;
 797         }
 798
 799         DBG(cdev, "%s config #%d: %s\n",
 800             usb_speed_string(gadget->speed),
 801             number, c ? c->label : "unconfigured");
 802
 803         if (!c)
 804                 goto done;
 805
 806         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 807         cdev->config = c;
 808
 809         /* Initialize all interfaces by setting them to altsetting zero. */
 810         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 811                 struct usb_function     *f = c->interface[tmp];
 812                 struct usb_descriptor_header **descriptors;
 813
 814                 if (!f)
 815                         break;
 816
 817                 /*
 818                  * Record which endpoints are used by the function. This is used
 819                  * to dispatch control requests targeted at that endpoint to the
 820                  * function's setup callback instead of the current
 821                  * configuration's setup callback.
 822                  */
 823                 descriptors = function_descriptors(f, gadget->speed);
 824
 825                 for (; *descriptors; ++descriptors) {
 826                         struct usb_endpoint_descriptor *ep;
 827                         int addr;
 828
 829                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 830                                 continue;
 831
 832                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 833                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 834                              |  (ep->bEndpointAddress & 0x0f);
 835                         set_bit(addr, f->endpoints);
 836                 }
 837
 838                 result = f->set_alt(f, tmp, 0);
 839                 if (result < 0) {
 840                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 841                                         tmp, f->name, f, result);
 842
 843                         reset_config(cdev);
 844                         goto done;
 845                 }
 846
 847                 if (result == USB_GADGET_DELAYED_STATUS) {
 848                         DBG(cdev,
 849                          "%s: interface %d (%s) requested delayed status\n",
 850                                         __func__, tmp, f->name);
 851                         cdev->delayed_status++;
 852                         DBG(cdev, "delayed_status count %d\n",
 853                                         cdev->delayed_status);
 854                 }
 855         }
 856
 857         /* when we return, be sure our power usage is valid */
 858         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 859         if (gadget->speed < USB_SPEED_SUPER)
 860                 power = min(power, 500U);
 861         else
 862                 power = min(power, 900U);
 863 done:
 864         usb_gadget_vbus_draw(gadget, power);
 865         if (result >= 0 && cdev->delayed_status)
 866                 result = USB_GADGET_DELAYED_STATUS;
 867         return result;
 868 }
 869
 870 int usb_add_config_only(struct usb_composite_dev *cdev,
 871                 struct usb_configuration *config)
 872 {
 873         struct usb_configuration *c;
 874
 875         if (!config->bConfigurationValue)
 876                 return -EINVAL;
 877
 878         /* Prevent duplicate configuration identifiers */
 879         list_for_each_entry(c, &cdev->configs, list) {
 880                 if (c->bConfigurationValue == config->bConfigurationValue)
 881                         return -EBUSY;
 882         }
 883
 884         config->cdev = cdev;
 885         list_add_tail(&config->list, &cdev->configs);
 886
 887         INIT_LIST_HEAD(&config->functions);
 888         config->next_interface_id = 0;
 889         memset(config->interface, 0, sizeof(config->interface));
 890
 891         return 0;
 892 }
 893 EXPORT_SYMBOL_GPL(usb_add_config_only);
 894
 895 /**
 896  * usb_add_config() - add a configuration to a device.
 897  * @cdev: wraps the USB gadget
 898  * @config: the configuration, with bConfigurationValue assigned
 899  * @bind: the configuration's bind function
 900  * Context: single threaded during gadget setup
 901  *
 902  * One of the main tasks of a composite @bind() routine is to
 903  * add each of the configurations it supports, using this routine.
 904  *
 905  * This function returns the value of the configuration's @bind(), which
 906  * is zero for success else a negative errno value.  Binding configurations
 907  * assigns global resources including string IDs, and per-configuration
 908  * resources such as interface IDs and endpoints.
 909  */
 910 int usb_add_config(struct usb_composite_dev *cdev,
 911                 struct usb_configuration *config,
 912                 int (*bind)(struct usb_configuration *))
 913 {
 914         int                             status = -EINVAL;
 915
 916         if (!bind)
 917                 goto done;
 918
 919         DBG(cdev, "adding config #%u '%s'/%p\n",
 920                         config->bConfigurationValue,
 921                         config->label, config);
 922
 923         status = usb_add_config_only(cdev, config);
 924         if (status)
 925                 goto done;
 926
 927         status = bind(config);
 928         if (status < 0) {
 929                 while (!list_empty(&config->functions)) {
 930                         struct usb_function             *f;
 931
 932                         f = list_first_entry(&config->functions,
 933                                         struct usb_function, list);
 934                         list_del(&f->list);
 935                         if (f->unbind) {
 936                                 DBG(cdev, "unbind function '%s'/%p\n",
 937                                         f->name, f);
 938                                 f->unbind(config, f);
 939                                 /* may free memory for "f" */
 940                         }
 941                 }
 942                 list_del(&config->list);
 943                 config->cdev = NULL;
 944         } else {
 945                 unsigned        i;
 946
 947                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
 948                         config->bConfigurationValue, config,
 949                         config->superspeed_plus ? " superplus" : "",
 950                         config->superspeed ? " super" : "",
 951                         config->highspeed ? " high" : "",
 952                         config->fullspeed
 953                                 ? (gadget_is_dualspeed(cdev->gadget)
 954                                         ? " full"
 955                                         : " full/low")
 956                                 : "");
 957
 958                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 959                         struct usb_function     *f = config->interface[i];
 960
 961                         if (!f)
 962                                 continue;
 963                         DBG(cdev, "  interface %d = %s/%p\n",
 964                                 i, f->name, f);
 965                 }
 966         }
 967
 968         /* set_alt(), or next bind(), sets up ep->claimed as needed */
 969         usb_ep_autoconfig_reset(cdev->gadget);
 970
 971 done:
 972         if (status)
 973                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 974                                 config->bConfigurationValue, status);
 975         return status;
 976 }
 977 EXPORT_SYMBOL_GPL(usb_add_config);
 978
 979 static void remove_config(struct usb_composite_dev *cdev,
 980                               struct usb_configuration *config)
 981 {
 982         while (!list_empty(&config->functions)) {
 983                 struct usb_function             *f;
 984
 985                 f = list_first_entry(&config->functions,
 986                                 struct usb_function, list);
 987
 988                 usb_remove_function(config, f);
 989         }
 990         list_del(&config->list);
 991         if (config->unbind) {
 992                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 993                 config->unbind(config);
 994                         /* may free memory for "c" */
 995         }
 996 }
 997
 998 /**
 999  * usb_remove_config() - remove a configuration from a device.
1000  * @cdev: wraps the USB gadget
1001  * @config: the configuration
1002  *
1003  * Drivers must call usb_gadget_disconnect before calling this function
1004  * to disconnect the device from the host and make sure the host will not
1005  * try to enumerate the device while we are changing the config list.
1006  */
1007 void usb_remove_config(struct usb_composite_dev *cdev,
1008                       struct usb_configuration *config)
1009 {
1010         unsigned long flags;
1011
1012         spin_lock_irqsave(&cdev->lock, flags);
1013
1014         if (cdev->config == config)
1015                 reset_config(cdev);
1016
1017         spin_unlock_irqrestore(&cdev->lock, flags);
1018
1019         remove_config(cdev, config);
1020 }
1021
1022 /*-------------------------------------------------------------------------*/
1023
1024 /* We support strings in multiple languages ... string descriptor zero
1025  * says which languages are supported.  The typical case will be that
1026  * only one language (probably English) is used, with i18n handled on
1027  * the host side.
1028  */
1029
1030 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1031 {
1032         const struct usb_gadget_strings *s;
1033         __le16                          language;
1034         __le16                          *tmp;
1035
1036         while (*sp) {
1037                 s = *sp;
1038                 language = cpu_to_le16(s->language);
1039                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
1040                         if (*tmp == language)
1041                                 goto repeat;
1042                 }
1043                 *tmp++ = language;
1044 repeat:
1045                 sp++;
1046         }
1047 }
1048
1049 static int lookup_string(
1050         struct usb_gadget_strings       **sp,
1051         void                            *buf,
1052         u16                             language,
1053         int                             id
1054 )
1055 {
1056         struct usb_gadget_strings       *s;
1057         int                             value;
1058
1059         while (*sp) {
1060                 s = *sp++;
1061                 if (s->language != language)
1062                         continue;
1063                 value = usb_gadget_get_string(s, id, buf);
1064                 if (value > 0)
1065                         return value;
1066         }
1067         return -EINVAL;
1068 }
1069
1070 static int get_string(struct usb_composite_dev *cdev,
1071                 void *buf, u16 language, int id)
1072 {
1073         struct usb_composite_driver     *composite = cdev->driver;
1074         struct usb_gadget_string_container *uc;
1075         struct usb_configuration        *c;
1076         struct usb_function             *f;
1077         int                             len;
1078
1079         /* Yes, not only is USB's i18n support probably more than most
1080          * folk will ever care about ... also, it's all supported here.
1081          * (Except for UTF8 support for Unicode's "Astral Planes".)
1082          */
1083
1084         /* 0 == report all available language codes */
1085         if (id == 0) {
1086                 struct usb_string_descriptor    *s = buf;
1087                 struct usb_gadget_strings       **sp;
1088
1089                 memset(s, 0, 256);
1090                 s->bDescriptorType = USB_DT_STRING;
1091
1092                 sp = composite->strings;
1093                 if (sp)
1094                         collect_langs(sp, s->wData);
1095
1096                 list_for_each_entry(c, &cdev->configs, list) {
1097                         sp = c->strings;
1098                         if (sp)
1099                                 collect_langs(sp, s->wData);
1100
1101                         list_for_each_entry(f, &c->functions, list) {
1102                                 sp = f->strings;
1103                                 if (sp)
1104                                         collect_langs(sp, s->wData);
1105                         }
1106                 }
1107                 list_for_each_entry(uc, &cdev->gstrings, list) {
1108                         struct usb_gadget_strings **sp;
1109
1110                         sp = get_containers_gs(uc);
1111                         collect_langs(sp, s->wData);
1112                 }
1113
1114                 for (len = 0; len <= 126 && s->wData[len]; len++)
1115                         continue;
1116                 if (!len)
1117                         return -EINVAL;
1118
1119                 s->bLength = 2 * (len + 1);
1120                 return s->bLength;
1121         }
1122
1123         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1124                 struct usb_os_string *b = buf;
1125                 b->bLength = sizeof(*b);
1126                 b->bDescriptorType = USB_DT_STRING;
1127                 compiletime_assert(
1128                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1129                         "qwSignature size must be equal to qw_sign");
1130                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1131                 b->bMS_VendorCode = cdev->b_vendor_code;
1132                 b->bPad = 0;
1133                 return sizeof(*b);
1134         }
1135
1136         list_for_each_entry(uc, &cdev->gstrings, list) {
1137                 struct usb_gadget_strings **sp;
1138
1139                 sp = get_containers_gs(uc);
1140                 len = lookup_string(sp, buf, language, id);
1141                 if (len > 0)
1142                         return len;
1143         }
1144
1145         /* String IDs are device-scoped, so we look up each string
1146          * table we're told about.  These lookups are infrequent;
1147          * simpler-is-better here.
1148          */
1149         if (composite->strings) {
1150                 len = lookup_string(composite->strings, buf, language, id);
1151                 if (len > 0)
1152                         return len;
1153         }
1154         list_for_each_entry(c, &cdev->configs, list) {
1155                 if (c->strings) {
1156                         len = lookup_string(c->strings, buf, language, id);
1157                         if (len > 0)
1158                                 return len;
1159                 }
1160                 list_for_each_entry(f, &c->functions, list) {
1161                         if (!f->strings)
1162                                 continue;
1163                         len = lookup_string(f->strings, buf, language, id);
1164                         if (len > 0)
1165                                 return len;
1166                 }
1167         }
1168         return -EINVAL;
1169 }
1170
1171 /**
1172  * usb_string_id() - allocate an unused string ID
1173  * @cdev: the device whose string descriptor IDs are being allocated
1174  * Context: single threaded during gadget setup
1175  *
1176  * @usb_string_id() is called from bind() callbacks to allocate
1177  * string IDs.  Drivers for functions, configurations, or gadgets will
1178  * then store that ID in the appropriate descriptors and string table.
1179  *
1180  * All string identifier should be allocated using this,
1181  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1182  * that for example different functions don't wrongly assign different
1183  * meanings to the same identifier.
1184  */
1185 int usb_string_id(struct usb_composite_dev *cdev)
1186 {
1187         if (cdev->next_string_id < 254) {
1188                 /* string id 0 is reserved by USB spec for list of
1189                  * supported languages */
1190                 /* 255 reserved as well? -- mina86 */
1191                 cdev->next_string_id++;
1192                 return cdev->next_string_id;
1193         }
1194         return -ENODEV;
1195 }
1196 EXPORT_SYMBOL_GPL(usb_string_id);
1197
1198 /**
1199  * usb_string_ids() - allocate unused string IDs in batch
1200  * @cdev: the device whose string descriptor IDs are being allocated
1201  * @str: an array of usb_string objects to assign numbers to
1202  * Context: single threaded during gadget setup
1203  *
1204  * @usb_string_ids() is called from bind() callbacks to allocate
1205  * string IDs.  Drivers for functions, configurations, or gadgets will
1206  * then copy IDs from the string table to the appropriate descriptors
1207  * and string table for other languages.
1208  *
1209  * All string identifier should be allocated using this,
1210  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1211  * example different functions don't wrongly assign different meanings
1212  * to the same identifier.
1213  */
1214 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1215 {
1216         int next = cdev->next_string_id;
1217
1218         for (; str->s; ++str) {
1219                 if (unlikely(next >= 254))
1220                         return -ENODEV;
1221                 str->id = ++next;
1222         }
1223
1224         cdev->next_string_id = next;
1225
1226         return 0;
1227 }
1228 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1229
1230 static struct usb_gadget_string_container *copy_gadget_strings(
1231                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1232                 unsigned n_strings)
1233 {
1234         struct usb_gadget_string_container *uc;
1235         struct usb_gadget_strings **gs_array;
1236         struct usb_gadget_strings *gs;
1237         struct usb_string *s;
1238         unsigned mem;
1239         unsigned n_gs;
1240         unsigned n_s;
1241         void *stash;
1242
1243         mem = sizeof(*uc);
1244         mem += sizeof(void *) * (n_gstrings + 1);
1245         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1246         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1247         uc = kmalloc(mem, GFP_KERNEL);
1248         if (!uc)
1249                 return ERR_PTR(-ENOMEM);
1250         gs_array = get_containers_gs(uc);
1251         stash = uc->stash;
1252         stash += sizeof(void *) * (n_gstrings + 1);
1253         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1254                 struct usb_string *org_s;
1255
1256                 gs_array[n_gs] = stash;
1257                 gs = gs_array[n_gs];
1258                 stash += sizeof(struct usb_gadget_strings);
1259                 gs->language = sp[n_gs]->language;
1260                 gs->strings = stash;
1261                 org_s = sp[n_gs]->strings;
1262
1263                 for (n_s = 0; n_s < n_strings; n_s++) {
1264                         s = stash;
1265                         stash += sizeof(struct usb_string);
1266                         if (org_s->s)
1267                                 s->s = org_s->s;
1268                         else
1269                                 s->s = "";
1270                         org_s++;
1271                 }
1272                 s = stash;
1273                 s->s = NULL;
1274                 stash += sizeof(struct usb_string);
1275
1276         }
1277         gs_array[n_gs] = NULL;
1278         return uc;
1279 }
1280
1281 /**
1282  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1283  * @cdev: the device whose string descriptor IDs are being allocated
1284  * and attached.
1285  * @sp: an array of usb_gadget_strings to attach.
1286  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1287  *
1288  * This function will create a deep copy of usb_gadget_strings and usb_string
1289  * and attach it to the cdev. The actual string (usb_string.s) will not be
1290  * copied but only a referenced will be made. The struct usb_gadget_strings
1291  * array may contain multiple languages and should be NULL terminated.
1292  * The ->language pointer of each struct usb_gadget_strings has to contain the
1293  * same amount of entries.
1294  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1295  * usb_string entry of es-ES contains the translation of the first usb_string
1296  * entry of en-US. Therefore both entries become the same id assign.
1297  */
1298 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1299                 struct usb_gadget_strings **sp, unsigned n_strings)
1300 {
1301         struct usb_gadget_string_container *uc;
1302         struct usb_gadget_strings **n_gs;
1303         unsigned n_gstrings = 0;
1304         unsigned i;
1305         int ret;
1306
1307         for (i = 0; sp[i]; i++)
1308                 n_gstrings++;
1309
1310         if (!n_gstrings)
1311                 return ERR_PTR(-EINVAL);
1312
1313         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1314         if (IS_ERR(uc))
1315                 return ERR_CAST(uc);
1316
1317         n_gs = get_containers_gs(uc);
1318         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1319         if (ret)
1320                 goto err;
1321
1322         for (i = 1; i < n_gstrings; i++) {
1323                 struct usb_string *m_s;
1324                 struct usb_string *s;
1325                 unsigned n;
1326
1327                 m_s = n_gs[0]->strings;
1328                 s = n_gs[i]->strings;
1329                 for (n = 0; n < n_strings; n++) {
1330                         s->id = m_s->id;
1331                         s++;
1332                         m_s++;
1333                 }
1334         }
1335         list_add_tail(&uc->list, &cdev->gstrings);
1336         return n_gs[0]->strings;
1337 err:
1338         kfree(uc);
1339         return ERR_PTR(ret);
1340 }
1341 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1342
1343 /**
1344  * usb_string_ids_n() - allocate unused string IDs in batch
1345  * @c: the device whose string descriptor IDs are being allocated
1346  * @n: number of string IDs to allocate
1347  * Context: single threaded during gadget setup
1348  *
1349  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1350  * valid IDs.  At least provided that @n is non-zero because if it
1351  * is, returns last requested ID which is now very useful information.
1352  *
1353  * @usb_string_ids_n() is called from bind() callbacks to allocate
1354  * string IDs.  Drivers for functions, configurations, or gadgets will
1355  * then store that ID in the appropriate descriptors and string table.
1356  *
1357  * All string identifier should be allocated using this,
1358  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1359  * example different functions don't wrongly assign different meanings
1360  * to the same identifier.
1361  */
1362 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1363 {
1364         unsigned next = c->next_string_id;
1365         if (unlikely(n > 254 || (unsigned)next + n > 254))
1366                 return -ENODEV;
1367         c->next_string_id += n;
1368         return next + 1;
1369 }
1370 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1371
1372 /*-------------------------------------------------------------------------*/
1373
1374 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1375 {
1376         struct usb_composite_dev *cdev;
1377
1378         if (req->status || req->actual != req->length)
1379                 DBG((struct usb_composite_dev *) ep->driver_data,
1380                                 "setup complete --> %d, %d/%d\n",
1381                                 req->status, req->actual, req->length);
1382
1383         /*
1384          * REVIST The same ep0 requests are shared with function drivers
1385          * so they don't have to maintain the same ->complete() stubs.
1386          *
1387          * Because of that, we need to check for the validity of ->context
1388          * here, even though we know we've set it to something useful.
1389          */
1390         if (!req->context)
1391                 return;
1392
1393         cdev = req->context;
1394
1395         if (cdev->req == req)
1396                 cdev->setup_pending = false;
1397         else if (cdev->os_desc_req == req)
1398                 cdev->os_desc_pending = false;
1399         else
1400                 WARN(1, "unknown request %p\n", req);
1401 }
1402
1403 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1404                 struct usb_request *req, gfp_t gfp_flags)
1405 {
1406         int ret;
1407
1408         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1409         if (ret == 0) {
1410                 if (cdev->req == req)
1411                         cdev->setup_pending = true;
1412                 else if (cdev->os_desc_req == req)
1413                         cdev->os_desc_pending = true;
1414                 else
1415                         WARN(1, "unknown request %p\n", req);
1416         }
1417
1418         return ret;
1419 }
1420
1421 static int count_ext_compat(struct usb_configuration *c)
1422 {
1423         int i, res;
1424
1425         res = 0;
1426         for (i = 0; i < c->next_interface_id; ++i) {
1427                 struct usb_function *f;
1428                 int j;
1429
1430                 f = c->interface[i];
1431                 for (j = 0; j < f->os_desc_n; ++j) {
1432                         struct usb_os_desc *d;
1433
1434                         if (i != f->os_desc_table[j].if_id)
1435                                 continue;
1436                         d = f->os_desc_table[j].os_desc;
1437                         if (d && d->ext_compat_id)
1438                                 ++res;
1439                 }
1440         }
1441         BUG_ON(res > 255);
1442         return res;
1443 }
1444
1445 static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1446 {
1447         int i, count;
1448
1449         count = 16;
1450         buf += 16;
1451         for (i = 0; i < c->next_interface_id; ++i) {
1452                 struct usb_function *f;
1453                 int j;
1454
1455                 f = c->interface[i];
1456                 for (j = 0; j < f->os_desc_n; ++j) {
1457                         struct usb_os_desc *d;
1458
1459                         if (i != f->os_desc_table[j].if_id)
1460                                 continue;
1461                         d = f->os_desc_table[j].os_desc;
1462                         if (d && d->ext_compat_id) {
1463                                 *buf++ = i;
1464                                 *buf++ = 0x01;
1465                                 memcpy(buf, d->ext_compat_id, 16);
1466                                 buf += 22;
1467                         } else {
1468                                 ++buf;
1469                                 *buf = 0x01;
1470                                 buf += 23;
1471                         }
1472                         count += 24;
1473                         if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1474                                 return count;
1475                 }
1476         }
1477
1478         return count;
1479 }
1480
1481 static int count_ext_prop(struct usb_configuration *c, int interface)
1482 {
1483         struct usb_function *f;
1484         int j;
1485
1486         f = c->interface[interface];
1487         for (j = 0; j < f->os_desc_n; ++j) {
1488                 struct usb_os_desc *d;
1489
1490                 if (interface != f->os_desc_table[j].if_id)
1491                         continue;
1492                 d = f->os_desc_table[j].os_desc;
1493                 if (d && d->ext_compat_id)
1494                         return d->ext_prop_count;
1495         }
1496         return 0;
1497 }
1498
1499 static int len_ext_prop(struct usb_configuration *c, int interface)
1500 {
1501         struct usb_function *f;
1502         struct usb_os_desc *d;
1503         int j, res;
1504
1505         res = 10; /* header length */
1506         f = c->interface[interface];
1507         for (j = 0; j < f->os_desc_n; ++j) {
1508                 if (interface != f->os_desc_table[j].if_id)
1509                         continue;
1510                 d = f->os_desc_table[j].os_desc;
1511                 if (d)
1512                         return min(res + d->ext_prop_len, 4096);
1513         }
1514         return res;
1515 }
1516
1517 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1518 {
1519         struct usb_function *f;
1520         struct usb_os_desc *d;
1521         struct usb_os_desc_ext_prop *ext_prop;
1522         int j, count, n, ret;
1523
1524         f = c->interface[interface];
1525         count = 10; /* header length */
1526         buf += 10;
1527         for (j = 0; j < f->os_desc_n; ++j) {
1528                 if (interface != f->os_desc_table[j].if_id)
1529                         continue;
1530                 d = f->os_desc_table[j].os_desc;
1531                 if (d)
1532                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1533                                 n = ext_prop->data_len +
1534                                         ext_prop->name_len + 14;
1535                                 if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1536                                         return count;
1537                                 usb_ext_prop_put_size(buf, n);
1538                                 usb_ext_prop_put_type(buf, ext_prop->type);
1539                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1540                                                             ext_prop->name_len);
1541                                 if (ret < 0)
1542                                         return ret;
1543                                 switch (ext_prop->type) {
1544                                 case USB_EXT_PROP_UNICODE:
1545                                 case USB_EXT_PROP_UNICODE_ENV:
1546                                 case USB_EXT_PROP_UNICODE_LINK:
1547                                         usb_ext_prop_put_unicode(buf, ret,
1548                                                          ext_prop->data,
1549                                                          ext_prop->data_len);
1550                                         break;
1551                                 case USB_EXT_PROP_BINARY:
1552                                         usb_ext_prop_put_binary(buf, ret,
1553                                                         ext_prop->data,
1554                                                         ext_prop->data_len);
1555                                         break;
1556                                 case USB_EXT_PROP_LE32:
1557                                         /* not implemented */
1558                                 case USB_EXT_PROP_BE32:
1559                                         /* not implemented */
1560                                 default:
1561                                         return -EINVAL;
1562                                 }
1563                                 buf += n;
1564                                 count += n;
1565                         }
1566         }
1567
1568         return count;
1569 }
1570
1571 /*
1572  * The setup() callback implements all the ep0 functionality that's
1573  * not handled lower down, in hardware or the hardware driver(like
1574  * device and endpoint feature flags, and their status).  It's all
1575  * housekeeping for the gadget function we're implementing.  Most of
1576  * the work is in config and function specific setup.
1577  */
1578 int
1579 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1580 {
1581         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1582         struct usb_request              *req = cdev->req;
1583         int                             value = -EOPNOTSUPP;
1584         int                             status = 0;
1585         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1586         u8                              intf = w_index & 0xFF;
1587         u16                             w_value = le16_to_cpu(ctrl->wValue);
1588         u16                             w_length = le16_to_cpu(ctrl->wLength);
1589         struct usb_function             *f = NULL;
1590         u8                              endp;
1591
1592         /* partial re-init of the response message; the function or the
1593          * gadget might need to intercept e.g. a control-OUT completion
1594          * when we delegate to it.
1595          */
1596         req->zero = 0;
1597         req->context = cdev;
1598         req->complete = composite_setup_complete;
1599         req->length = 0;
1600         gadget->ep0->driver_data = cdev;
1601
1602         /*
1603          * Don't let non-standard requests match any of the cases below
1604          * by accident.
1605          */
1606         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1607                 goto unknown;
1608
1609         switch (ctrl->bRequest) {
1610
1611         /* we handle all standard USB descriptors */
1612         case USB_REQ_GET_DESCRIPTOR:
1613                 if (ctrl->bRequestType != USB_DIR_IN)
1614                         goto unknown;
1615                 switch (w_value >> 8) {
1616
1617                 case USB_DT_DEVICE:
1618                         cdev->desc.bNumConfigurations =
1619                                 count_configs(cdev, USB_DT_DEVICE);
1620                         cdev->desc.bMaxPacketSize0 =
1621                                 cdev->gadget->ep0->maxpacket;
1622                         if (gadget_is_superspeed(gadget)) {
1623                                 if (gadget->speed >= USB_SPEED_SUPER) {
1624                                         cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1625                                         cdev->desc.bMaxPacketSize0 = 9;
1626                                 } else {
1627                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1628                                 }
1629                         } else {
1630                                 if (gadget->lpm_capable)
1631                                         cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1632                                 else
1633                                         cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1634                         }
1635
1636                         value = min(w_length, (u16) sizeof cdev->desc);
1637                         memcpy(req->buf, &cdev->desc, value);
1638                         break;
1639                 case USB_DT_DEVICE_QUALIFIER:
1640                         if (!gadget_is_dualspeed(gadget) ||
1641                             gadget->speed >= USB_SPEED_SUPER)
1642                                 break;
1643                         device_qual(cdev);
1644                         value = min_t(int, w_length,
1645                                 sizeof(struct usb_qualifier_descriptor));
1646                         break;
1647                 case USB_DT_OTHER_SPEED_CONFIG:
1648                         if (!gadget_is_dualspeed(gadget) ||
1649                             gadget->speed >= USB_SPEED_SUPER)
1650                                 break;
1651                         /* FALLTHROUGH */
1652                 case USB_DT_CONFIG:
1653                         value = config_desc(cdev, w_value);
1654                         if (value >= 0)
1655                                 value = min(w_length, (u16) value);
1656                         break;
1657                 case USB_DT_STRING:
1658                         value = get_string(cdev, req->buf,
1659                                         w_index, w_value & 0xff);
1660                         if (value >= 0)
1661                                 value = min(w_length, (u16) value);
1662                         break;
1663                 case USB_DT_BOS:
1664                         if (gadget_is_superspeed(gadget) ||
1665                             gadget->lpm_capable) {
1666                                 value = bos_desc(cdev);
1667                                 value = min(w_length, (u16) value);
1668                         }
1669                         break;
1670                 case USB_DT_OTG:
1671                         if (gadget_is_otg(gadget)) {
1672                                 struct usb_configuration *config;
1673                                 int otg_desc_len = 0;
1674
1675                                 if (cdev->config)
1676                                         config = cdev->config;
1677                                 else
1678                                         config = list_first_entry(
1679                                                         &cdev->configs,
1680                                                 struct usb_configuration, list);
1681                                 if (!config)
1682                                         goto done;
1683
1684                                 if (gadget->otg_caps &&
1685                                         (gadget->otg_caps->otg_rev >= 0x0200))
1686                                         otg_desc_len += sizeof(
1687                                                 struct usb_otg20_descriptor);
1688                                 else
1689                                         otg_desc_len += sizeof(
1690                                                 struct usb_otg_descriptor);
1691
1692                                 value = min_t(int, w_length, otg_desc_len);
1693                                 memcpy(req->buf, config->descriptors[0], value);
1694                         }
1695                         break;
1696                 }
1697                 break;
1698
1699         /* any number of configs can work */
1700         case USB_REQ_SET_CONFIGURATION:
1701                 if (ctrl->bRequestType != 0)
1702                         goto unknown;
1703                 if (gadget_is_otg(gadget)) {
1704                         if (gadget->a_hnp_support)
1705                                 DBG(cdev, "HNP available\n");
1706                         else if (gadget->a_alt_hnp_support)
1707                                 DBG(cdev, "HNP on another port\n");
1708                         else
1709                                 VDBG(cdev, "HNP inactive\n");
1710                 }
1711                 spin_lock(&cdev->lock);
1712                 value = set_config(cdev, ctrl, w_value);
1713                 spin_unlock(&cdev->lock);
1714                 break;
1715         case USB_REQ_GET_CONFIGURATION:
1716                 if (ctrl->bRequestType != USB_DIR_IN)
1717                         goto unknown;
1718                 if (cdev->config)
1719                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1720                 else
1721                         *(u8 *)req->buf = 0;
1722                 value = min(w_length, (u16) 1);
1723                 break;
1724
1725         /* function drivers must handle get/set altsetting */
1726         case USB_REQ_SET_INTERFACE:
1727                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1728                         goto unknown;
1729                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1730                         break;
1731                 f = cdev->config->interface[intf];
1732                 if (!f)
1733                         break;
1734
1735                 /*
1736                  * If there's no get_alt() method, we know only altsetting zero
1737                  * works. There is no need to check if set_alt() is not NULL
1738                  * as we check this in usb_add_function().
1739                  */
1740                 if (w_value && !f->get_alt)
1741                         break;
1742
1743                 spin_lock(&cdev->lock);
1744                 value = f->set_alt(f, w_index, w_value);
1745                 if (value == USB_GADGET_DELAYED_STATUS) {
1746                         DBG(cdev,
1747                          "%s: interface %d (%s) requested delayed status\n",
1748                                         __func__, intf, f->name);
1749                         cdev->delayed_status++;
1750                         DBG(cdev, "delayed_status count %d\n",
1751                                         cdev->delayed_status);
1752                 }
1753                 spin_unlock(&cdev->lock);
1754                 break;
1755         case USB_REQ_GET_INTERFACE:
1756                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1757                         goto unknown;
1758                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1759                         break;
1760                 f = cdev->config->interface[intf];
1761                 if (!f)
1762                         break;
1763                 /* lots of interfaces only need altsetting zero... */
1764                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1765                 if (value < 0)
1766                         break;
1767                 *((u8 *)req->buf) = value;
1768                 value = min(w_length, (u16) 1);
1769                 break;
1770         case USB_REQ_GET_STATUS:
1771                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1772                                                 (w_index == OTG_STS_SELECTOR)) {
1773                         if (ctrl->bRequestType != (USB_DIR_IN |
1774                                                         USB_RECIP_DEVICE))
1775                                 goto unknown;
1776                         *((u8 *)req->buf) = gadget->host_request_flag;
1777                         value = 1;
1778                         break;
1779                 }
1780
1781                 /*
1782                  * USB 3.0 additions:
1783                  * Function driver should handle get_status request. If such cb
1784                  * wasn't supplied we respond with default value = 0
1785                  * Note: function driver should supply such cb only for the
1786                  * first interface of the function
1787                  */
1788                 if (!gadget_is_superspeed(gadget))
1789                         goto unknown;
1790                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1791                         goto unknown;
1792                 value = 2;      /* This is the length of the get_status reply */
1793                 put_unaligned_le16(0, req->buf);
1794                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1795                         break;
1796                 f = cdev->config->interface[intf];
1797                 if (!f)
1798                         break;
1799                 status = f->get_status ? f->get_status(f) : 0;
1800                 if (status < 0)
1801                         break;
1802                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1803                 break;
1804         /*
1805          * Function drivers should handle SetFeature/ClearFeature
1806          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1807          * only for the first interface of the function
1808          */
1809         case USB_REQ_CLEAR_FEATURE:
1810         case USB_REQ_SET_FEATURE:
1811                 if (!gadget_is_superspeed(gadget))
1812                         goto unknown;
1813                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1814                         goto unknown;
1815                 switch (w_value) {
1816                 case USB_INTRF_FUNC_SUSPEND:
1817                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1818                                 break;
1819                         f = cdev->config->interface[intf];
1820                         if (!f)
1821                                 break;
1822                         value = 0;
1823                         if (f->func_suspend)
1824                                 value = f->func_suspend(f, w_index >> 8);
1825                         if (value < 0) {
1826                                 ERROR(cdev,
1827                                       "func_suspend() returned error %d\n",
1828                                       value);
1829                                 value = 0;
1830                         }
1831                         break;
1832                 }
1833                 break;
1834         default:
1835 unknown:
1836                 /*
1837                  * OS descriptors handling
1838                  */
1839                 if (cdev->use_os_string && cdev->os_desc_config &&
1840                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1841                     ctrl->bRequest == cdev->b_vendor_code) {
1842                         struct usb_configuration        *os_desc_cfg;
1843                         u8                              *buf;
1844                         int                             interface;
1845                         int                             count = 0;
1846
1847                         req = cdev->os_desc_req;
1848                         req->context = cdev;
1849                         req->complete = composite_setup_complete;
1850                         buf = req->buf;
1851                         os_desc_cfg = cdev->os_desc_config;
1852                         w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1853                         memset(buf, 0, w_length);
1854                         buf[5] = 0x01;
1855                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1856                         case USB_RECIP_DEVICE:
1857                                 if (w_index != 0x4 || (w_value >> 8))
1858                                         break;
1859                                 buf[6] = w_index;
1860                                 /* Number of ext compat interfaces */
1861                                 count = count_ext_compat(os_desc_cfg);
1862                                 buf[8] = count;
1863                                 count *= 24; /* 24 B/ext compat desc */
1864                                 count += 16; /* header */
1865                                 put_unaligned_le32(count, buf);
1866                                 value = w_length;
1867                                 if (w_length > 0x10) {
1868                                         value = fill_ext_compat(os_desc_cfg, buf);
1869                                         value = min_t(u16, w_length, value);
1870                                 }
1871                                 break;
1872                         case USB_RECIP_INTERFACE:
1873                                 if (w_index != 0x5 || (w_value >> 8))
1874                                         break;
1875                                 interface = w_value & 0xFF;
1876                                 buf[6] = w_index;
1877                                 count = count_ext_prop(os_desc_cfg,
1878                                         interface);
1879                                 put_unaligned_le16(count, buf + 8);
1880                                 count = len_ext_prop(os_desc_cfg,
1881                                         interface);
1882                                 put_unaligned_le32(count, buf);
1883                                 value = w_length;
1884                                 if (w_length > 0x0A) {
1885                                         value = fill_ext_prop(os_desc_cfg,
1886                                                               interface, buf);
1887                                         if (value >= 0)
1888                                                 value = min_t(u16, w_length, value);
1889                                 }
1890                                 break;
1891                         }
1892
1893                         goto check_value;
1894                 }
1895
1896                 VDBG(cdev,
1897                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1898                         ctrl->bRequestType, ctrl->bRequest,
1899                         w_value, w_index, w_length);
1900
1901                 /* functions always handle their interfaces and endpoints...
1902                  * punt other recipients (other, WUSB, ...) to the current
1903                  * configuration code.
1904                  */
1905                 if (cdev->config) {
1906                         list_for_each_entry(f, &cdev->config->functions, list)
1907                                 if (f->req_match &&
1908                                     f->req_match(f, ctrl, false))
1909                                         goto try_fun_setup;
1910                 } else {
1911                         struct usb_configuration *c;
1912                         list_for_each_entry(c, &cdev->configs, list)
1913                                 list_for_each_entry(f, &c->functions, list)
1914                                         if (f->req_match &&
1915                                             f->req_match(f, ctrl, true))
1916                                                 goto try_fun_setup;
1917                 }
1918                 f = NULL;
1919
1920                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1921                 case USB_RECIP_INTERFACE:
1922                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1923                                 break;
1924                         f = cdev->config->interface[intf];
1925                         break;
1926
1927                 case USB_RECIP_ENDPOINT:
1928                         if (!cdev->config)
1929                                 break;
1930                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1931                         list_for_each_entry(f, &cdev->config->functions, list) {
1932                                 if (test_bit(endp, f->endpoints))
1933                                         break;
1934                         }
1935                         if (&f->list == &cdev->config->functions)
1936                                 f = NULL;
1937                         break;
1938                 }
1939 try_fun_setup:
1940                 if (f && f->setup)
1941                         value = f->setup(f, ctrl);
1942                 else {
1943                         struct usb_configuration        *c;
1944
1945                         c = cdev->config;
1946                         if (!c)
1947                                 goto done;
1948
1949                         /* try current config's setup */
1950                         if (c->setup) {
1951                                 value = c->setup(c, ctrl);
1952                                 goto done;
1953                         }
1954
1955                         /* try the only function in the current config */
1956                         if (!list_is_singular(&c->functions))
1957                                 goto done;
1958                         f = list_first_entry(&c->functions, struct usb_function,
1959                                              list);
1960                         if (f->setup)
1961                                 value = f->setup(f, ctrl);
1962                 }
1963
1964                 goto done;
1965         }
1966
1967 check_value:
1968         /* respond with data transfer before status phase? */
1969         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1970                 req->length = value;
1971                 req->context = cdev;
1972                 req->zero = value < w_length;
1973                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
1974                 if (value < 0) {
1975                         DBG(cdev, "ep_queue --> %d\n", value);
1976                         req->status = 0;
1977                         composite_setup_complete(gadget->ep0, req);
1978                 }
1979         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1980                 WARN(cdev,
1981                         "%s: Delayed status not supported for w_length != 0",
1982                         __func__);
1983         }
1984
1985 done:
1986         /* device either stalls (value < 0) or reports success */
1987         return value;
1988 }
1989
1990 void composite_disconnect(struct usb_gadget *gadget)
1991 {
1992         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1993         unsigned long                   flags;
1994
1995         /* REVISIT:  should we have config and device level
1996          * disconnect callbacks?
1997          */
1998         spin_lock_irqsave(&cdev->lock, flags);
1999         cdev->suspended = 0;
2000         if (cdev->config)
2001                 reset_config(cdev);
2002         if (cdev->driver->disconnect)
2003                 cdev->driver->disconnect(cdev);
2004         spin_unlock_irqrestore(&cdev->lock, flags);
2005 }
2006
2007 /*-------------------------------------------------------------------------*/
2008
2009 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2010                               char *buf)
2011 {
2012         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2013         struct usb_composite_dev *cdev = get_gadget_data(gadget);
2014
2015         return sprintf(buf, "%d\n", cdev->suspended);
2016 }
2017 static DEVICE_ATTR_RO(suspended);
2018
2019 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2020 {
2021         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2022         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2023         struct usb_string               *dev_str = gstr->strings;
2024
2025         /* composite_disconnect() must already have been called
2026          * by the underlying peripheral controller driver!
2027          * so there's no i/o concurrency that could affect the
2028          * state protected by cdev->lock.
2029          */
2030         WARN_ON(cdev->config);
2031
2032         while (!list_empty(&cdev->configs)) {
2033                 struct usb_configuration        *c;
2034                 c = list_first_entry(&cdev->configs,
2035                                 struct usb_configuration, list);
2036                 remove_config(cdev, c);
2037         }
2038         if (cdev->driver->unbind && unbind_driver)
2039                 cdev->driver->unbind(cdev);
2040
2041         composite_dev_cleanup(cdev);
2042
2043         if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2044                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2045
2046         kfree(cdev->def_manufacturer);
2047         kfree(cdev);
2048         set_gadget_data(gadget, NULL);
2049 }
2050
2051 static void composite_unbind(struct usb_gadget *gadget)
2052 {
2053         __composite_unbind(gadget, true);
2054 }
2055
2056 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2057                 const struct usb_device_descriptor *old)
2058 {
2059         __le16 idVendor;
2060         __le16 idProduct;
2061         __le16 bcdDevice;
2062         u8 iSerialNumber;
2063         u8 iManufacturer;
2064         u8 iProduct;
2065
2066         /*
2067          * these variables may have been set in
2068          * usb_composite_overwrite_options()
2069          */
2070         idVendor = new->idVendor;
2071         idProduct = new->idProduct;
2072         bcdDevice = new->bcdDevice;
2073         iSerialNumber = new->iSerialNumber;
2074         iManufacturer = new->iManufacturer;
2075         iProduct = new->iProduct;
2076
2077         *new = *old;
2078         if (idVendor)
2079                 new->idVendor = idVendor;
2080         if (idProduct)
2081                 new->idProduct = idProduct;
2082         if (bcdDevice)
2083                 new->bcdDevice = bcdDevice;
2084         else
2085                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2086         if (iSerialNumber)
2087                 new->iSerialNumber = iSerialNumber;
2088         if (iManufacturer)
2089                 new->iManufacturer = iManufacturer;
2090         if (iProduct)
2091                 new->iProduct = iProduct;
2092 }
2093
2094 int composite_dev_prepare(struct usb_composite_driver *composite,
2095                 struct usb_composite_dev *cdev)
2096 {
2097         struct usb_gadget *gadget = cdev->gadget;
2098         int ret = -ENOMEM;
2099
2100         /* preallocate control response and buffer */
2101         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2102         if (!cdev->req)
2103                 return -ENOMEM;
2104
2105         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2106         if (!cdev->req->buf)
2107                 goto fail;
2108
2109         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2110         if (ret)
2111                 goto fail_dev;
2112
2113         cdev->req->complete = composite_setup_complete;
2114         cdev->req->context = cdev;
2115         gadget->ep0->driver_data = cdev;
2116
2117         cdev->driver = composite;
2118
2119         /*
2120          * As per USB compliance update, a device that is actively drawing
2121          * more than 100mA from USB must report itself as bus-powered in
2122          * the GetStatus(DEVICE) call.
2123          */
2124         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2125                 usb_gadget_set_selfpowered(gadget);
2126
2127         /* interface and string IDs start at zero via kzalloc.
2128          * we force endpoints to start unassigned; few controller
2129          * drivers will zero ep->driver_data.
2130          */
2131         usb_ep_autoconfig_reset(gadget);
2132         return 0;
2133 fail_dev:
2134         kfree(cdev->req->buf);
2135 fail:
2136         usb_ep_free_request(gadget->ep0, cdev->req);
2137         cdev->req = NULL;
2138         return ret;
2139 }
2140
2141 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2142                                   struct usb_ep *ep0)
2143 {
2144         int ret = 0;
2145
2146         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2147         if (!cdev->os_desc_req) {
2148                 ret = -ENOMEM;
2149                 goto end;
2150         }
2151
2152         cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2153                                          GFP_KERNEL);
2154         if (!cdev->os_desc_req->buf) {
2155                 ret = -ENOMEM;
2156                 usb_ep_free_request(ep0, cdev->os_desc_req);
2157                 goto end;
2158         }
2159         cdev->os_desc_req->context = cdev;
2160         cdev->os_desc_req->complete = composite_setup_complete;
2161 end:
2162         return ret;
2163 }
2164
2165 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2166 {
2167         struct usb_gadget_string_container *uc, *tmp;
2168         struct usb_ep                      *ep, *tmp_ep;
2169
2170         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2171                 list_del(&uc->list);
2172                 kfree(uc);
2173         }
2174         if (cdev->os_desc_req) {
2175                 if (cdev->os_desc_pending)
2176                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2177
2178                 kfree(cdev->os_desc_req->buf);
2179                 cdev->os_desc_req->buf = NULL;
2180                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2181                 cdev->os_desc_req = NULL;
2182         }
2183         if (cdev->req) {
2184                 if (cdev->setup_pending)
2185                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2186
2187                 kfree(cdev->req->buf);
2188                 cdev->req->buf = NULL;
2189                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2190                 cdev->req = NULL;
2191         }
2192         cdev->next_string_id = 0;
2193         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2194
2195         /*
2196          * Some UDC backends have a dynamic EP allocation scheme.
2197          *
2198          * In that case, the dispose() callback is used to notify the
2199          * backend that the EPs are no longer in use.
2200          *
2201          * Note: The UDC backend can remove the EP from the ep_list as
2202          *       a result, so we need to use the _safe list iterator.
2203          */
2204         list_for_each_entry_safe(ep, tmp_ep,
2205                                  &cdev->gadget->ep_list, ep_list) {
2206                 if (ep->ops->dispose)
2207                         ep->ops->dispose(ep);
2208         }
2209 }
2210
2211 static int composite_bind(struct usb_gadget *gadget,
2212                 struct usb_gadget_driver *gdriver)
2213 {
2214         struct usb_composite_dev        *cdev;
2215         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2216         int                             status = -ENOMEM;
2217
2218         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2219         if (!cdev)
2220                 return status;
2221
2222         spin_lock_init(&cdev->lock);
2223         cdev->gadget = gadget;
2224         set_gadget_data(gadget, cdev);
2225         INIT_LIST_HEAD(&cdev->configs);
2226         INIT_LIST_HEAD(&cdev->gstrings);
2227
2228         status = composite_dev_prepare(composite, cdev);
2229         if (status)
2230                 goto fail;
2231
2232         /* composite gadget needs to assign strings for whole device (like
2233          * serial number), register function drivers, potentially update
2234          * power state and consumption, etc
2235          */
2236         status = composite->bind(cdev);
2237         if (status < 0)
2238                 goto fail;
2239
2240         if (cdev->use_os_string) {
2241                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2242                 if (status)
2243                         goto fail;
2244         }
2245
2246         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2247
2248         /* has userspace failed to provide a serial number? */
2249         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2250                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2251
2252         INFO(cdev, "%s ready\n", composite->name);
2253         return 0;
2254
2255 fail:
2256         __composite_unbind(gadget, false);
2257         return status;
2258 }
2259
2260 /*-------------------------------------------------------------------------*/
2261
2262 void composite_suspend(struct usb_gadget *gadget)
2263 {
2264         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2265         struct usb_function             *f;
2266
2267         /* REVISIT:  should we have config level
2268          * suspend/resume callbacks?
2269          */
2270         DBG(cdev, "suspend\n");
2271         if (cdev->config) {
2272                 list_for_each_entry(f, &cdev->config->functions, list) {
2273                         if (f->suspend)
2274                                 f->suspend(f);
2275                 }
2276         }
2277         if (cdev->driver->suspend)
2278                 cdev->driver->suspend(cdev);
2279
2280         cdev->suspended = 1;
2281
2282         usb_gadget_vbus_draw(gadget, 2);
2283 }
2284
2285 void composite_resume(struct usb_gadget *gadget)
2286 {
2287         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2288         struct usb_function             *f;
2289         unsigned                        maxpower;
2290
2291         /* REVISIT:  should we have config level
2292          * suspend/resume callbacks?
2293          */
2294         DBG(cdev, "resume\n");
2295         if (cdev->driver->resume)
2296                 cdev->driver->resume(cdev);
2297         if (cdev->config) {
2298                 list_for_each_entry(f, &cdev->config->functions, list) {
2299                         if (f->resume)
2300                                 f->resume(f);
2301                 }
2302
2303                 maxpower = cdev->config->MaxPower ?
2304                         cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2305                 if (gadget->speed < USB_SPEED_SUPER)
2306                         maxpower = min(maxpower, 500U);
2307                 else
2308                         maxpower = min(maxpower, 900U);
2309
2310                 usb_gadget_vbus_draw(gadget, maxpower);
2311         }
2312
2313         cdev->suspended = 0;
2314 }
2315
2316 /*-------------------------------------------------------------------------*/
2317
2318 static const struct usb_gadget_driver composite_driver_template = {
2319         .bind           = composite_bind,
2320         .unbind         = composite_unbind,
2321
2322         .setup          = composite_setup,
2323         .reset          = composite_disconnect,
2324         .disconnect     = composite_disconnect,
2325
2326         .suspend        = composite_suspend,
2327         .resume         = composite_resume,
2328
2329         .driver = {
2330                 .owner          = THIS_MODULE,
2331         },
2332 };
2333
2334 /**
2335  * usb_composite_probe() - register a composite driver
2336  * @driver: the driver to register
2337  *
2338  * Context: single threaded during gadget setup
2339  *
2340  * This function is used to register drivers using the composite driver
2341  * framework.  The return value is zero, or a negative errno value.
2342  * Those values normally come from the driver's @bind method, which does
2343  * all the work of setting up the driver to match the hardware.
2344  *
2345  * On successful return, the gadget is ready to respond to requests from
2346  * the host, unless one of its components invokes usb_gadget_disconnect()
2347  * while it was binding.  That would usually be done in order to wait for
2348  * some userspace participation.
2349  */
2350 int usb_composite_probe(struct usb_composite_driver *driver)
2351 {
2352         struct usb_gadget_driver *gadget_driver;
2353
2354         if (!driver || !driver->dev || !driver->bind)
2355                 return -EINVAL;
2356
2357         if (!driver->name)
2358                 driver->name = "composite";
2359
2360         driver->gadget_driver = composite_driver_template;
2361         gadget_driver = &driver->gadget_driver;
2362
2363         gadget_driver->function =  (char *) driver->name;
2364         gadget_driver->driver.name = driver->name;
2365         gadget_driver->max_speed = driver->max_speed;
2366
2367         return usb_gadget_probe_driver(gadget_driver);
2368 }
2369 EXPORT_SYMBOL_GPL(usb_composite_probe);
2370
2371 /**
2372  * usb_composite_unregister() - unregister a composite driver
2373  * @driver: the driver to unregister
2374  *
2375  * This function is used to unregister drivers using the composite
2376  * driver framework.
2377  */
2378 void usb_composite_unregister(struct usb_composite_driver *driver)
2379 {
2380         usb_gadget_unregister_driver(&driver->gadget_driver);
2381 }
2382 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2383
2384 /**
2385  * usb_composite_setup_continue() - Continue with the control transfer
2386  * @cdev: the composite device who's control transfer was kept waiting
2387  *
2388  * This function must be called by the USB function driver to continue
2389  * with the control transfer's data/status stage in case it had requested to
2390  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2391  * can request the composite framework to delay the setup request's data/status
2392  * stages by returning USB_GADGET_DELAYED_STATUS.
2393  */
2394 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2395 {
2396         int                     value;
2397         struct usb_request      *req = cdev->req;
2398         unsigned long           flags;
2399
2400         DBG(cdev, "%s\n", __func__);
2401         spin_lock_irqsave(&cdev->lock, flags);
2402
2403         if (cdev->delayed_status == 0) {
2404                 WARN(cdev, "%s: Unexpected call\n", __func__);
2405
2406         } else if (--cdev->delayed_status == 0) {
2407                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2408                 req->length = 0;
2409                 req->context = cdev;
2410                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2411                 if (value < 0) {
2412                         DBG(cdev, "ep_queue --> %d\n", value);
2413                         req->status = 0;
2414                         composite_setup_complete(cdev->gadget->ep0, req);
2415                 }
2416         }
2417
2418         spin_unlock_irqrestore(&cdev->lock, flags);
2419 }
2420 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2421
2422 static char *composite_default_mfr(struct usb_gadget *gadget)
2423 {
2424         return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2425                          init_utsname()->release, gadget->name);
2426 }
2427
2428 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2429                 struct usb_composite_overwrite *covr)
2430 {
2431         struct usb_device_descriptor    *desc = &cdev->desc;
2432         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2433         struct usb_string               *dev_str = gstr->strings;
2434
2435         if (covr->idVendor)
2436                 desc->idVendor = cpu_to_le16(covr->idVendor);
2437
2438         if (covr->idProduct)
2439                 desc->idProduct = cpu_to_le16(covr->idProduct);
2440
2441         if (covr->bcdDevice)
2442                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2443
2444         if (covr->serial_number) {
2445                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2446                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2447         }
2448         if (covr->manufacturer) {
2449                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2450                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2451
2452         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2453                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2454                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2455                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2456         }
2457
2458         if (covr->product) {
2459                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2460                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2461         }
2462 }
2463 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2464
2465 MODULE_LICENSE("GPL");
2466 MODULE_AUTHOR("David Brownell");