drivers/usb/gadget/composite.c

   1 /*
   2  * composite.c - infrastructure for Composite USB Gadgets
   3  *
   4  * Copyright (C) 2006-2008 David Brownell
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 /* #define VERBOSE_DEBUG */
  13
  14 #include <linux/kallsyms.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/device.h>
  19 #include <linux/utsname.h>
  20
  21 #include <linux/usb/composite.h>
  22 #include <linux/usb/otg.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "u_os_desc.h"
  26
  27 /**
  28  * struct usb_os_string - represents OS String to be reported by a gadget
  29  * @bLength: total length of the entire descritor, always 0x12
  30  * @bDescriptorType: USB_DT_STRING
  31  * @qwSignature: the OS String proper
  32  * @bMS_VendorCode: code used by the host for subsequent requests
  33  * @bPad: not used, must be zero
  34  */
  35 struct usb_os_string {
  36         __u8    bLength;
  37         __u8    bDescriptorType;
  38         __u8    qwSignature[OS_STRING_QW_SIGN_LEN];
  39         __u8    bMS_VendorCode;
  40         __u8    bPad;
  41 } __packed;
  42
  43 /*
  44  * The code in this file is utility code, used to build a gadget driver
  45  * from one or more "function" drivers, one or more "configuration"
  46  * objects, and a "usb_composite_driver" by gluing them together along
  47  * with the relevant device-wide data.
  48  */
  49
  50 static struct usb_gadget_strings **get_containers_gs(
  51                 struct usb_gadget_string_container *uc)
  52 {
  53         return (struct usb_gadget_strings **)uc->stash;
  54 }
  55
  56 /**
  57  * function_descriptors() - get function descriptors for speed
  58  * @f: the function
  59  * @speed: the speed
  60  *
  61  * Returns the descriptors or NULL if not set.
  62  */
  63 static struct usb_descriptor_header **
  64 function_descriptors(struct usb_function *f,
  65                      enum usb_device_speed speed)
  66 {
  67         struct usb_descriptor_header **descriptors;
  68
  69         /*
  70          * NOTE: we try to help gadget drivers which might not be setting
  71          * max_speed appropriately.
  72          */
  73
  74         switch (speed) {
  75         case USB_SPEED_SUPER_PLUS:
  76                 descriptors = f->ssp_descriptors;
  77                 if (descriptors)
  78                         break;
  79                 /* FALLTHROUGH */
  80         case USB_SPEED_SUPER:
  81                 descriptors = f->ss_descriptors;
  82                 if (descriptors)
  83                         break;
  84                 /* FALLTHROUGH */
  85         case USB_SPEED_HIGH:
  86                 descriptors = f->hs_descriptors;
  87                 if (descriptors)
  88                         break;
  89                 /* FALLTHROUGH */
  90         default:
  91                 descriptors = f->fs_descriptors;
  92         }
  93
  94         /*
  95          * if we can't find any descriptors at all, then this gadget deserves to
  96          * Oops with a NULL pointer dereference
  97          */
  98
  99         return descriptors;
 100 }
 101
 102 /**
 103  * next_ep_desc() - advance to the next EP descriptor
 104  * @t: currect pointer within descriptor array
 105  *
 106  * Return: next EP descriptor or NULL
 107  *
 108  * Iterate over @t until either EP descriptor found or
 109  * NULL (that indicates end of list) encountered
 110  */
 111 static struct usb_descriptor_header**
 112 next_ep_desc(struct usb_descriptor_header **t)
 113 {
 114         for (; *t; t++) {
 115                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
 116                         return t;
 117         }
 118         return NULL;
 119 }
 120
 121 /*
 122  * for_each_ep_desc()- iterate over endpoint descriptors in the
 123  *              descriptors list
 124  * @start:      pointer within descriptor array.
 125  * @ep_desc:    endpoint descriptor to use as the loop cursor
 126  */
 127 #define for_each_ep_desc(start, ep_desc) \
 128         for (ep_desc = next_ep_desc(start); \
 129               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
 130
 131 /**
 132  * config_ep_by_speed() - configures the given endpoint
 133  * according to gadget speed.
 134  * @g: pointer to the gadget
 135  * @f: usb function
 136  * @_ep: the endpoint to configure
 137  *
 138  * Return: error code, 0 on success
 139  *
 140  * This function chooses the right descriptors for a given
 141  * endpoint according to gadget speed and saves it in the
 142  * endpoint desc field. If the endpoint already has a descriptor
 143  * assigned to it - overwrites it with currently corresponding
 144  * descriptor. The endpoint maxpacket field is updated according
 145  * to the chosen descriptor.
 146  * Note: the supplied function should hold all the descriptors
 147  * for supported speeds
 148  */
 149 int config_ep_by_speed(struct usb_gadget *g,
 150                         struct usb_function *f,
 151                         struct usb_ep *_ep)
 152 {
 153         struct usb_composite_dev        *cdev = get_gadget_data(g);
 154         struct usb_endpoint_descriptor *chosen_desc = NULL;
 155         struct usb_descriptor_header **speed_desc = NULL;
 156
 157         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 158         int want_comp_desc = 0;
 159
 160         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 161
 162         if (!g || !f || !_ep)
 163                 return -EIO;
 164
 165         /* select desired speed */
 166         switch (g->speed) {
 167         case USB_SPEED_SUPER_PLUS:
 168                 if (gadget_is_superspeed_plus(g)) {
 169                         speed_desc = f->ssp_descriptors;
 170                         want_comp_desc = 1;
 171                         break;
 172                 }
 173                 /* else: Fall trough */
 174         case USB_SPEED_SUPER:
 175                 if (gadget_is_superspeed(g)) {
 176                         speed_desc = f->ss_descriptors;
 177                         want_comp_desc = 1;
 178                         break;
 179                 }
 180                 /* else: Fall trough */
 181         case USB_SPEED_HIGH:
 182                 if (gadget_is_dualspeed(g)) {
 183                         speed_desc = f->hs_descriptors;
 184                         break;
 185                 }
 186                 /* else: fall through */
 187         default:
 188                 speed_desc = f->fs_descriptors;
 189         }
 190         /* find descriptors */
 191         for_each_ep_desc(speed_desc, d_spd) {
 192                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 193                 if (chosen_desc->bEndpointAddress == _ep->address)
 194                         goto ep_found;
 195         }
 196         return -EIO;
 197
 198 ep_found:
 199         /* commit results */
 200         _ep->maxpacket = usb_endpoint_maxp(chosen_desc) & 0x7ff;
 201         _ep->desc = chosen_desc;
 202         _ep->comp_desc = NULL;
 203         _ep->maxburst = 0;
 204         _ep->mult = 1;
 205
 206         if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 207                                 usb_endpoint_xfer_int(_ep->desc)))
 208                 _ep->mult = ((usb_endpoint_maxp(_ep->desc) & 0x1800) >> 11) + 1;
 209
 210         if (!want_comp_desc)
 211                 return 0;
 212
 213         /*
 214          * Companion descriptor should follow EP descriptor
 215          * USB 3.0 spec, #9.6.7
 216          */
 217         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 218         if (!comp_desc ||
 219             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 220                 return -EIO;
 221         _ep->comp_desc = comp_desc;
 222         if (g->speed >= USB_SPEED_SUPER) {
 223                 switch (usb_endpoint_type(_ep->desc)) {
 224                 case USB_ENDPOINT_XFER_ISOC:
 225                         /* mult: bits 1:0 of bmAttributes */
 226                         _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 227                 case USB_ENDPOINT_XFER_BULK:
 228                 case USB_ENDPOINT_XFER_INT:
 229                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 230                         break;
 231                 default:
 232                         if (comp_desc->bMaxBurst != 0)
 233                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 234                         _ep->maxburst = 1;
 235                         break;
 236                 }
 237         }
 238         return 0;
 239 }
 240 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 241
 242 /**
 243  * usb_add_function() - add a function to a configuration
 244  * @config: the configuration
 245  * @function: the function being added
 246  * Context: single threaded during gadget setup
 247  *
 248  * After initialization, each configuration must have one or more
 249  * functions added to it.  Adding a function involves calling its @bind()
 250  * method to allocate resources such as interface and string identifiers
 251  * and endpoints.
 252  *
 253  * This function returns the value of the function's bind(), which is
 254  * zero for success else a negative errno value.
 255  */
 256 int usb_add_function(struct usb_configuration *config,
 257                 struct usb_function *function)
 258 {
 259         int     value = -EINVAL;
 260
 261         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 262                         function->name, function,
 263                         config->label, config);
 264
 265         if (!function->set_alt || !function->disable)
 266                 goto done;
 267
 268         function->config = config;
 269         list_add_tail(&function->list, &config->functions);
 270
 271         if (function->bind_deactivated) {
 272                 value = usb_function_deactivate(function);
 273                 if (value)
 274                         goto done;
 275         }
 276
 277         /* REVISIT *require* function->bind? */
 278         if (function->bind) {
 279                 value = function->bind(config, function);
 280                 if (value < 0) {
 281                         list_del(&function->list);
 282                         function->config = NULL;
 283                 }
 284         } else
 285                 value = 0;
 286
 287         /* We allow configurations that don't work at both speeds.
 288          * If we run into a lowspeed Linux system, treat it the same
 289          * as full speed ... it's the function drivers that will need
 290          * to avoid bulk and ISO transfers.
 291          */
 292         if (!config->fullspeed && function->fs_descriptors)
 293                 config->fullspeed = true;
 294         if (!config->highspeed && function->hs_descriptors)
 295                 config->highspeed = true;
 296         if (!config->superspeed && function->ss_descriptors)
 297                 config->superspeed = true;
 298         if (!config->superspeed_plus && function->ssp_descriptors)
 299                 config->superspeed_plus = true;
 300
 301 done:
 302         if (value)
 303                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 304                                 function->name, function, value);
 305         return value;
 306 }
 307 EXPORT_SYMBOL_GPL(usb_add_function);
 308
 309 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 310 {
 311         if (f->disable)
 312                 f->disable(f);
 313
 314         bitmap_zero(f->endpoints, 32);
 315         list_del(&f->list);
 316         if (f->unbind)
 317                 f->unbind(c, f);
 318 }
 319 EXPORT_SYMBOL_GPL(usb_remove_function);
 320
 321 /**
 322  * usb_function_deactivate - prevent function and gadget enumeration
 323  * @function: the function that isn't yet ready to respond
 324  *
 325  * Blocks response of the gadget driver to host enumeration by
 326  * preventing the data line pullup from being activated.  This is
 327  * normally called during @bind() processing to change from the
 328  * initial "ready to respond" state, or when a required resource
 329  * becomes available.
 330  *
 331  * For example, drivers that serve as a passthrough to a userspace
 332  * daemon can block enumeration unless that daemon (such as an OBEX,
 333  * MTP, or print server) is ready to handle host requests.
 334  *
 335  * Not all systems support software control of their USB peripheral
 336  * data pullups.
 337  *
 338  * Returns zero on success, else negative errno.
 339  */
 340 int usb_function_deactivate(struct usb_function *function)
 341 {
 342         struct usb_composite_dev        *cdev = function->config->cdev;
 343         unsigned long                   flags;
 344         int                             status = 0;
 345
 346         spin_lock_irqsave(&cdev->lock, flags);
 347
 348         if (cdev->deactivations == 0)
 349                 status = usb_gadget_deactivate(cdev->gadget);
 350         if (status == 0)
 351                 cdev->deactivations++;
 352
 353         spin_unlock_irqrestore(&cdev->lock, flags);
 354         return status;
 355 }
 356 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 357
 358 /**
 359  * usb_function_activate - allow function and gadget enumeration
 360  * @function: function on which usb_function_activate() was called
 361  *
 362  * Reverses effect of usb_function_deactivate().  If no more functions
 363  * are delaying their activation, the gadget driver will respond to
 364  * host enumeration procedures.
 365  *
 366  * Returns zero on success, else negative errno.
 367  */
 368 int usb_function_activate(struct usb_function *function)
 369 {
 370         struct usb_composite_dev        *cdev = function->config->cdev;
 371         unsigned long                   flags;
 372         int                             status = 0;
 373
 374         spin_lock_irqsave(&cdev->lock, flags);
 375
 376         if (WARN_ON(cdev->deactivations == 0))
 377                 status = -EINVAL;
 378         else {
 379                 cdev->deactivations--;
 380                 if (cdev->deactivations == 0)
 381                         status = usb_gadget_activate(cdev->gadget);
 382         }
 383
 384         spin_unlock_irqrestore(&cdev->lock, flags);
 385         return status;
 386 }
 387 EXPORT_SYMBOL_GPL(usb_function_activate);
 388
 389 /**
 390  * usb_interface_id() - allocate an unused interface ID
 391  * @config: configuration associated with the interface
 392  * @function: function handling the interface
 393  * Context: single threaded during gadget setup
 394  *
 395  * usb_interface_id() is called from usb_function.bind() callbacks to
 396  * allocate new interface IDs.  The function driver will then store that
 397  * ID in interface, association, CDC union, and other descriptors.  It
 398  * will also handle any control requests targeted at that interface,
 399  * particularly changing its altsetting via set_alt().  There may
 400  * also be class-specific or vendor-specific requests to handle.
 401  *
 402  * All interface identifier should be allocated using this routine, to
 403  * ensure that for example different functions don't wrongly assign
 404  * different meanings to the same identifier.  Note that since interface
 405  * identifiers are configuration-specific, functions used in more than
 406  * one configuration (or more than once in a given configuration) need
 407  * multiple versions of the relevant descriptors.
 408  *
 409  * Returns the interface ID which was allocated; or -ENODEV if no
 410  * more interface IDs can be allocated.
 411  */
 412 int usb_interface_id(struct usb_configuration *config,
 413                 struct usb_function *function)
 414 {
 415         unsigned id = config->next_interface_id;
 416
 417         if (id < MAX_CONFIG_INTERFACES) {
 418                 config->interface[id] = function;
 419                 config->next_interface_id = id + 1;
 420                 return id;
 421         }
 422         return -ENODEV;
 423 }
 424 EXPORT_SYMBOL_GPL(usb_interface_id);
 425
 426 static u8 encode_bMaxPower(enum usb_device_speed speed,
 427                 struct usb_configuration *c)
 428 {
 429         unsigned val;
 430
 431         if (c->MaxPower)
 432                 val = c->MaxPower;
 433         else
 434                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 435         if (!val)
 436                 return 0;
 437         switch (speed) {
 438         case USB_SPEED_SUPER:
 439                 return DIV_ROUND_UP(val, 8);
 440         default:
 441                 return DIV_ROUND_UP(val, 2);
 442         }
 443 }
 444
 445 static int config_buf(struct usb_configuration *config,
 446                 enum usb_device_speed speed, void *buf, u8 type)
 447 {
 448         struct usb_config_descriptor    *c = buf;
 449         void                            *next = buf + USB_DT_CONFIG_SIZE;
 450         int                             len;
 451         struct usb_function             *f;
 452         int                             status;
 453
 454         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 455         /* write the config descriptor */
 456         c = buf;
 457         c->bLength = USB_DT_CONFIG_SIZE;
 458         c->bDescriptorType = type;
 459         /* wTotalLength is written later */
 460         c->bNumInterfaces = config->next_interface_id;
 461         c->bConfigurationValue = config->bConfigurationValue;
 462         c->iConfiguration = config->iConfiguration;
 463         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 464         c->bMaxPower = encode_bMaxPower(speed, config);
 465
 466         /* There may be e.g. OTG descriptors */
 467         if (config->descriptors) {
 468                 status = usb_descriptor_fillbuf(next, len,
 469                                 config->descriptors);
 470                 if (status < 0)
 471                         return status;
 472                 len -= status;
 473                 next += status;
 474         }
 475
 476         /* add each function's descriptors */
 477         list_for_each_entry(f, &config->functions, list) {
 478                 struct usb_descriptor_header **descriptors;
 479
 480                 descriptors = function_descriptors(f, speed);
 481                 if (!descriptors)
 482                         continue;
 483                 status = usb_descriptor_fillbuf(next, len,
 484                         (const struct usb_descriptor_header **) descriptors);
 485                 if (status < 0)
 486                         return status;
 487                 len -= status;
 488                 next += status;
 489         }
 490
 491         len = next - buf;
 492         c->wTotalLength = cpu_to_le16(len);
 493         return len;
 494 }
 495
 496 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 497 {
 498         struct usb_gadget               *gadget = cdev->gadget;
 499         struct usb_configuration        *c;
 500         struct list_head                *pos;
 501         u8                              type = w_value >> 8;
 502         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 503
 504         if (gadget->speed >= USB_SPEED_SUPER)
 505                 speed = gadget->speed;
 506         else if (gadget_is_dualspeed(gadget)) {
 507                 int     hs = 0;
 508                 if (gadget->speed == USB_SPEED_HIGH)
 509                         hs = 1;
 510                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 511                         hs = !hs;
 512                 if (hs)
 513                         speed = USB_SPEED_HIGH;
 514
 515         }
 516
 517         /* This is a lookup by config *INDEX* */
 518         w_value &= 0xff;
 519
 520         pos = &cdev->configs;
 521         c = cdev->os_desc_config;
 522         if (c)
 523                 goto check_config;
 524
 525         while ((pos = pos->next) !=  &cdev->configs) {
 526                 c = list_entry(pos, typeof(*c), list);
 527
 528                 /* skip OS Descriptors config which is handled separately */
 529                 if (c == cdev->os_desc_config)
 530                         continue;
 531
 532 check_config:
 533                 /* ignore configs that won't work at this speed */
 534                 switch (speed) {
 535                 case USB_SPEED_SUPER_PLUS:
 536                         if (!c->superspeed_plus)
 537                                 continue;
 538                         break;
 539                 case USB_SPEED_SUPER:
 540                         if (!c->superspeed)
 541                                 continue;
 542                         break;
 543                 case USB_SPEED_HIGH:
 544                         if (!c->highspeed)
 545                                 continue;
 546                         break;
 547                 default:
 548                         if (!c->fullspeed)
 549                                 continue;
 550                 }
 551
 552                 if (w_value == 0)
 553                         return config_buf(c, speed, cdev->req->buf, type);
 554                 w_value--;
 555         }
 556         return -EINVAL;
 557 }
 558
 559 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 560 {
 561         struct usb_gadget               *gadget = cdev->gadget;
 562         struct usb_configuration        *c;
 563         unsigned                        count = 0;
 564         int                             hs = 0;
 565         int                             ss = 0;
 566         int                             ssp = 0;
 567
 568         if (gadget_is_dualspeed(gadget)) {
 569                 if (gadget->speed == USB_SPEED_HIGH)
 570                         hs = 1;
 571                 if (gadget->speed == USB_SPEED_SUPER)
 572                         ss = 1;
 573                 if (gadget->speed == USB_SPEED_SUPER_PLUS)
 574                         ssp = 1;
 575                 if (type == USB_DT_DEVICE_QUALIFIER)
 576                         hs = !hs;
 577         }
 578         list_for_each_entry(c, &cdev->configs, list) {
 579                 /* ignore configs that won't work at this speed */
 580                 if (ssp) {
 581                         if (!c->superspeed_plus)
 582                                 continue;
 583                 } else if (ss) {
 584                         if (!c->superspeed)
 585                                 continue;
 586                 } else if (hs) {
 587                         if (!c->highspeed)
 588                                 continue;
 589                 } else {
 590                         if (!c->fullspeed)
 591                                 continue;
 592                 }
 593                 count++;
 594         }
 595         return count;
 596 }
 597
 598 /**
 599  * bos_desc() - prepares the BOS descriptor.
 600  * @cdev: pointer to usb_composite device to generate the bos
 601  *      descriptor for
 602  *
 603  * This function generates the BOS (Binary Device Object)
 604  * descriptor and its device capabilities descriptors. The BOS
 605  * descriptor should be supported by a SuperSpeed device.
 606  */
 607 static int bos_desc(struct usb_composite_dev *cdev)
 608 {
 609         struct usb_ext_cap_descriptor   *usb_ext;
 610         struct usb_ss_cap_descriptor    *ss_cap;
 611         struct usb_dcd_config_params    dcd_config_params;
 612         struct usb_bos_descriptor       *bos = cdev->req->buf;
 613
 614         bos->bLength = USB_DT_BOS_SIZE;
 615         bos->bDescriptorType = USB_DT_BOS;
 616
 617         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 618         bos->bNumDeviceCaps = 0;
 619
 620         /*
 621          * A SuperSpeed device shall include the USB2.0 extension descriptor
 622          * and shall support LPM when operating in USB2.0 HS mode.
 623          */
 624         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 625         bos->bNumDeviceCaps++;
 626         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 627         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 628         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 629         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 630         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | USB_BESL_SUPPORT);
 631
 632         /*
 633          * The Superspeed USB Capability descriptor shall be implemented by all
 634          * SuperSpeed devices.
 635          */
 636         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 637         bos->bNumDeviceCaps++;
 638         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 639         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 640         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 641         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 642         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 643         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 644                                 USB_FULL_SPEED_OPERATION |
 645                                 USB_HIGH_SPEED_OPERATION |
 646                                 USB_5GBPS_OPERATION);
 647         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 648
 649         /* Get Controller configuration */
 650         if (cdev->gadget->ops->get_config_params)
 651                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 652         else {
 653                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 654                 dcd_config_params.bU2DevExitLat =
 655                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 656         }
 657         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 658         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 659
 660         /* The SuperSpeedPlus USB Device Capability descriptor */
 661         if (gadget_is_superspeed_plus(cdev->gadget)) {
 662                 struct usb_ssp_cap_descriptor *ssp_cap;
 663
 664                 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 665                 bos->bNumDeviceCaps++;
 666
 667                 /*
 668                  * Report typical values.
 669                  */
 670
 671                 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
 672                 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
 673                 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 674                 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 675                 ssp_cap->bReserved = 0;
 676                 ssp_cap->wReserved = 0;
 677
 678                 /* SSAC = 1 (2 attributes) */
 679                 ssp_cap->bmAttributes = cpu_to_le32(1);
 680
 681                 /* Min RX/TX Lane Count = 1 */
 682                 ssp_cap->wFunctionalitySupport =
 683                         cpu_to_le16((1 << 8) | (1 << 12));
 684
 685                 /*
 686                  * bmSublinkSpeedAttr[0]:
 687                  *   ST  = Symmetric, RX
 688                  *   LSE =  3 (Gbps)
 689                  *   LP  =  1 (SuperSpeedPlus)
 690                  *   LSM = 10 (10 Gbps)
 691                  */
 692                 ssp_cap->bmSublinkSpeedAttr[0] =
 693                         cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
 694                 /*
 695                  * bmSublinkSpeedAttr[1] =
 696                  *   ST  = Symmetric, TX
 697                  *   LSE =  3 (Gbps)
 698                  *   LP  =  1 (SuperSpeedPlus)
 699                  *   LSM = 10 (10 Gbps)
 700                  */
 701                 ssp_cap->bmSublinkSpeedAttr[1] =
 702                         cpu_to_le32((3 << 4) | (1 << 14) |
 703                                     (0xa << 16) | (1 << 7));
 704         }
 705
 706         return le16_to_cpu(bos->wTotalLength);
 707 }
 708
 709 static void device_qual(struct usb_composite_dev *cdev)
 710 {
 711         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 712
 713         qual->bLength = sizeof(*qual);
 714         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 715         /* POLICY: same bcdUSB and device type info at both speeds */
 716         qual->bcdUSB = cdev->desc.bcdUSB;
 717         qual->bDeviceClass = cdev->desc.bDeviceClass;
 718         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 719         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 720         /* ASSUME same EP0 fifo size at both speeds */
 721         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 722         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 723         qual->bRESERVED = 0;
 724 }
 725
 726 /*-------------------------------------------------------------------------*/
 727
 728 static void reset_config(struct usb_composite_dev *cdev)
 729 {
 730         struct usb_function             *f;
 731
 732         DBG(cdev, "reset config\n");
 733
 734         list_for_each_entry(f, &cdev->config->functions, list) {
 735                 if (f->disable)
 736                         f->disable(f);
 737
 738                 bitmap_zero(f->endpoints, 32);
 739         }
 740         cdev->config = NULL;
 741         cdev->delayed_status = 0;
 742 }
 743
 744 static int set_config(struct usb_composite_dev *cdev,
 745                 const struct usb_ctrlrequest *ctrl, unsigned number)
 746 {
 747         struct usb_gadget       *gadget = cdev->gadget;
 748         struct usb_configuration *c = NULL;
 749         int                     result = -EINVAL;
 750         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 751         int                     tmp;
 752
 753         if (number) {
 754                 list_for_each_entry(c, &cdev->configs, list) {
 755                         if (c->bConfigurationValue == number) {
 756                                 /*
 757                                  * We disable the FDs of the previous
 758                                  * configuration only if the new configuration
 759                                  * is a valid one
 760                                  */
 761                                 if (cdev->config)
 762                                         reset_config(cdev);
 763                                 result = 0;
 764                                 break;
 765                         }
 766                 }
 767                 if (result < 0)
 768                         goto done;
 769         } else { /* Zero configuration value - need to reset the config */
 770                 if (cdev->config)
 771                         reset_config(cdev);
 772                 result = 0;
 773         }
 774
 775         INFO(cdev, "%s config #%d: %s\n",
 776              usb_speed_string(gadget->speed),
 777              number, c ? c->label : "unconfigured");
 778
 779         if (!c)
 780                 goto done;
 781
 782         usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 783         cdev->config = c;
 784
 785         /* Initialize all interfaces by setting them to altsetting zero. */
 786         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 787                 struct usb_function     *f = c->interface[tmp];
 788                 struct usb_descriptor_header **descriptors;
 789
 790                 if (!f)
 791                         break;
 792
 793                 /*
 794                  * Record which endpoints are used by the function. This is used
 795                  * to dispatch control requests targeted at that endpoint to the
 796                  * function's setup callback instead of the current
 797                  * configuration's setup callback.
 798                  */
 799                 descriptors = function_descriptors(f, gadget->speed);
 800
 801                 for (; *descriptors; ++descriptors) {
 802                         struct usb_endpoint_descriptor *ep;
 803                         int addr;
 804
 805                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 806                                 continue;
 807
 808                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 809                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 810                              |  (ep->bEndpointAddress & 0x0f);
 811                         set_bit(addr, f->endpoints);
 812                 }
 813
 814                 result = f->set_alt(f, tmp, 0);
 815                 if (result < 0) {
 816                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 817                                         tmp, f->name, f, result);
 818
 819                         reset_config(cdev);
 820                         goto done;
 821                 }
 822
 823                 if (result == USB_GADGET_DELAYED_STATUS) {
 824                         DBG(cdev,
 825                          "%s: interface %d (%s) requested delayed status\n",
 826                                         __func__, tmp, f->name);
 827                         cdev->delayed_status++;
 828                         DBG(cdev, "delayed_status count %d\n",
 829                                         cdev->delayed_status);
 830                 }
 831         }
 832
 833         /* when we return, be sure our power usage is valid */
 834         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 835 done:
 836         usb_gadget_vbus_draw(gadget, power);
 837         if (result >= 0 && cdev->delayed_status)
 838                 result = USB_GADGET_DELAYED_STATUS;
 839         return result;
 840 }
 841
 842 int usb_add_config_only(struct usb_composite_dev *cdev,
 843                 struct usb_configuration *config)
 844 {
 845         struct usb_configuration *c;
 846
 847         if (!config->bConfigurationValue)
 848                 return -EINVAL;
 849
 850         /* Prevent duplicate configuration identifiers */
 851         list_for_each_entry(c, &cdev->configs, list) {
 852                 if (c->bConfigurationValue == config->bConfigurationValue)
 853                         return -EBUSY;
 854         }
 855
 856         config->cdev = cdev;
 857         list_add_tail(&config->list, &cdev->configs);
 858
 859         INIT_LIST_HEAD(&config->functions);
 860         config->next_interface_id = 0;
 861         memset(config->interface, 0, sizeof(config->interface));
 862
 863         return 0;
 864 }
 865 EXPORT_SYMBOL_GPL(usb_add_config_only);
 866
 867 /**
 868  * usb_add_config() - add a configuration to a device.
 869  * @cdev: wraps the USB gadget
 870  * @config: the configuration, with bConfigurationValue assigned
 871  * @bind: the configuration's bind function
 872  * Context: single threaded during gadget setup
 873  *
 874  * One of the main tasks of a composite @bind() routine is to
 875  * add each of the configurations it supports, using this routine.
 876  *
 877  * This function returns the value of the configuration's @bind(), which
 878  * is zero for success else a negative errno value.  Binding configurations
 879  * assigns global resources including string IDs, and per-configuration
 880  * resources such as interface IDs and endpoints.
 881  */
 882 int usb_add_config(struct usb_composite_dev *cdev,
 883                 struct usb_configuration *config,
 884                 int (*bind)(struct usb_configuration *))
 885 {
 886         int                             status = -EINVAL;
 887
 888         if (!bind)
 889                 goto done;
 890
 891         DBG(cdev, "adding config #%u '%s'/%p\n",
 892                         config->bConfigurationValue,
 893                         config->label, config);
 894
 895         status = usb_add_config_only(cdev, config);
 896         if (status)
 897                 goto done;
 898
 899         status = bind(config);
 900         if (status < 0) {
 901                 while (!list_empty(&config->functions)) {
 902                         struct usb_function             *f;
 903
 904                         f = list_first_entry(&config->functions,
 905                                         struct usb_function, list);
 906                         list_del(&f->list);
 907                         if (f->unbind) {
 908                                 DBG(cdev, "unbind function '%s'/%p\n",
 909                                         f->name, f);
 910                                 f->unbind(config, f);
 911                                 /* may free memory for "f" */
 912                         }
 913                 }
 914                 list_del(&config->list);
 915                 config->cdev = NULL;
 916         } else {
 917                 unsigned        i;
 918
 919                 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
 920                         config->bConfigurationValue, config,
 921                         config->superspeed_plus ? " superplus" : "",
 922                         config->superspeed ? " super" : "",
 923                         config->highspeed ? " high" : "",
 924                         config->fullspeed
 925                                 ? (gadget_is_dualspeed(cdev->gadget)
 926                                         ? " full"
 927                                         : " full/low")
 928                                 : "");
 929
 930                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 931                         struct usb_function     *f = config->interface[i];
 932
 933                         if (!f)
 934                                 continue;
 935                         DBG(cdev, "  interface %d = %s/%p\n",
 936                                 i, f->name, f);
 937                 }
 938         }
 939
 940         /* set_alt(), or next bind(), sets up ep->claimed as needed */
 941         usb_ep_autoconfig_reset(cdev->gadget);
 942
 943 done:
 944         if (status)
 945                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 946                                 config->bConfigurationValue, status);
 947         return status;
 948 }
 949 EXPORT_SYMBOL_GPL(usb_add_config);
 950
 951 static void remove_config(struct usb_composite_dev *cdev,
 952                               struct usb_configuration *config)
 953 {
 954         while (!list_empty(&config->functions)) {
 955                 struct usb_function             *f;
 956
 957                 f = list_first_entry(&config->functions,
 958                                 struct usb_function, list);
 959                 list_del(&f->list);
 960                 if (f->unbind) {
 961                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 962                         f->unbind(config, f);
 963                         /* may free memory for "f" */
 964                 }
 965         }
 966         list_del(&config->list);
 967         if (config->unbind) {
 968                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 969                 config->unbind(config);
 970                         /* may free memory for "c" */
 971         }
 972 }
 973
 974 /**
 975  * usb_remove_config() - remove a configuration from a device.
 976  * @cdev: wraps the USB gadget
 977  * @config: the configuration
 978  *
 979  * Drivers must call usb_gadget_disconnect before calling this function
 980  * to disconnect the device from the host and make sure the host will not
 981  * try to enumerate the device while we are changing the config list.
 982  */
 983 void usb_remove_config(struct usb_composite_dev *cdev,
 984                       struct usb_configuration *config)
 985 {
 986         unsigned long flags;
 987
 988         spin_lock_irqsave(&cdev->lock, flags);
 989
 990         if (cdev->config == config)
 991                 reset_config(cdev);
 992
 993         spin_unlock_irqrestore(&cdev->lock, flags);
 994
 995         remove_config(cdev, config);
 996 }
 997
 998 /*-------------------------------------------------------------------------*/
 999
1000 /* We support strings in multiple languages ... string descriptor zero
1001  * says which languages are supported.  The typical case will be that
1002  * only one language (probably English) is used, with i18n handled on
1003  * the host side.
1004  */
1005
1006 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1007 {
1008         const struct usb_gadget_strings *s;
1009         __le16                          language;
1010         __le16                          *tmp;
1011
1012         while (*sp) {
1013                 s = *sp;
1014                 language = cpu_to_le16(s->language);
1015                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
1016                         if (*tmp == language)
1017                                 goto repeat;
1018                 }
1019                 *tmp++ = language;
1020 repeat:
1021                 sp++;
1022         }
1023 }
1024
1025 static int lookup_string(
1026         struct usb_gadget_strings       **sp,
1027         void                            *buf,
1028         u16                             language,
1029         int                             id
1030 )
1031 {
1032         struct usb_gadget_strings       *s;
1033         int                             value;
1034
1035         while (*sp) {
1036                 s = *sp++;
1037                 if (s->language != language)
1038                         continue;
1039                 value = usb_gadget_get_string(s, id, buf);
1040                 if (value > 0)
1041                         return value;
1042         }
1043         return -EINVAL;
1044 }
1045
1046 static int get_string(struct usb_composite_dev *cdev,
1047                 void *buf, u16 language, int id)
1048 {
1049         struct usb_composite_driver     *composite = cdev->driver;
1050         struct usb_gadget_string_container *uc;
1051         struct usb_configuration        *c;
1052         struct usb_function             *f;
1053         int                             len;
1054
1055         /* Yes, not only is USB's i18n support probably more than most
1056          * folk will ever care about ... also, it's all supported here.
1057          * (Except for UTF8 support for Unicode's "Astral Planes".)
1058          */
1059
1060         /* 0 == report all available language codes */
1061         if (id == 0) {
1062                 struct usb_string_descriptor    *s = buf;
1063                 struct usb_gadget_strings       **sp;
1064
1065                 memset(s, 0, 256);
1066                 s->bDescriptorType = USB_DT_STRING;
1067
1068                 sp = composite->strings;
1069                 if (sp)
1070                         collect_langs(sp, s->wData);
1071
1072                 list_for_each_entry(c, &cdev->configs, list) {
1073                         sp = c->strings;
1074                         if (sp)
1075                                 collect_langs(sp, s->wData);
1076
1077                         list_for_each_entry(f, &c->functions, list) {
1078                                 sp = f->strings;
1079                                 if (sp)
1080                                         collect_langs(sp, s->wData);
1081                         }
1082                 }
1083                 list_for_each_entry(uc, &cdev->gstrings, list) {
1084                         struct usb_gadget_strings **sp;
1085
1086                         sp = get_containers_gs(uc);
1087                         collect_langs(sp, s->wData);
1088                 }
1089
1090                 for (len = 0; len <= 126 && s->wData[len]; len++)
1091                         continue;
1092                 if (!len)
1093                         return -EINVAL;
1094
1095                 s->bLength = 2 * (len + 1);
1096                 return s->bLength;
1097         }
1098
1099         if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1100                 struct usb_os_string *b = buf;
1101                 b->bLength = sizeof(*b);
1102                 b->bDescriptorType = USB_DT_STRING;
1103                 compiletime_assert(
1104                         sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1105                         "qwSignature size must be equal to qw_sign");
1106                 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1107                 b->bMS_VendorCode = cdev->b_vendor_code;
1108                 b->bPad = 0;
1109                 return sizeof(*b);
1110         }
1111
1112         list_for_each_entry(uc, &cdev->gstrings, list) {
1113                 struct usb_gadget_strings **sp;
1114
1115                 sp = get_containers_gs(uc);
1116                 len = lookup_string(sp, buf, language, id);
1117                 if (len > 0)
1118                         return len;
1119         }
1120
1121         /* String IDs are device-scoped, so we look up each string
1122          * table we're told about.  These lookups are infrequent;
1123          * simpler-is-better here.
1124          */
1125         if (composite->strings) {
1126                 len = lookup_string(composite->strings, buf, language, id);
1127                 if (len > 0)
1128                         return len;
1129         }
1130         list_for_each_entry(c, &cdev->configs, list) {
1131                 if (c->strings) {
1132                         len = lookup_string(c->strings, buf, language, id);
1133                         if (len > 0)
1134                                 return len;
1135                 }
1136                 list_for_each_entry(f, &c->functions, list) {
1137                         if (!f->strings)
1138                                 continue;
1139                         len = lookup_string(f->strings, buf, language, id);
1140                         if (len > 0)
1141                                 return len;
1142                 }
1143         }
1144         return -EINVAL;
1145 }
1146
1147 /**
1148  * usb_string_id() - allocate an unused string ID
1149  * @cdev: the device whose string descriptor IDs are being allocated
1150  * Context: single threaded during gadget setup
1151  *
1152  * @usb_string_id() is called from bind() callbacks to allocate
1153  * string IDs.  Drivers for functions, configurations, or gadgets will
1154  * then store that ID in the appropriate descriptors and string table.
1155  *
1156  * All string identifier should be allocated using this,
1157  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1158  * that for example different functions don't wrongly assign different
1159  * meanings to the same identifier.
1160  */
1161 int usb_string_id(struct usb_composite_dev *cdev)
1162 {
1163         if (cdev->next_string_id < 254) {
1164                 /* string id 0 is reserved by USB spec for list of
1165                  * supported languages */
1166                 /* 255 reserved as well? -- mina86 */
1167                 cdev->next_string_id++;
1168                 return cdev->next_string_id;
1169         }
1170         return -ENODEV;
1171 }
1172 EXPORT_SYMBOL_GPL(usb_string_id);
1173
1174 /**
1175  * usb_string_ids() - allocate unused string IDs in batch
1176  * @cdev: the device whose string descriptor IDs are being allocated
1177  * @str: an array of usb_string objects to assign numbers to
1178  * Context: single threaded during gadget setup
1179  *
1180  * @usb_string_ids() is called from bind() callbacks to allocate
1181  * string IDs.  Drivers for functions, configurations, or gadgets will
1182  * then copy IDs from the string table to the appropriate descriptors
1183  * and string table for other languages.
1184  *
1185  * All string identifier should be allocated using this,
1186  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1187  * example different functions don't wrongly assign different meanings
1188  * to the same identifier.
1189  */
1190 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1191 {
1192         int next = cdev->next_string_id;
1193
1194         for (; str->s; ++str) {
1195                 if (unlikely(next >= 254))
1196                         return -ENODEV;
1197                 str->id = ++next;
1198         }
1199
1200         cdev->next_string_id = next;
1201
1202         return 0;
1203 }
1204 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1205
1206 static struct usb_gadget_string_container *copy_gadget_strings(
1207                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1208                 unsigned n_strings)
1209 {
1210         struct usb_gadget_string_container *uc;
1211         struct usb_gadget_strings **gs_array;
1212         struct usb_gadget_strings *gs;
1213         struct usb_string *s;
1214         unsigned mem;
1215         unsigned n_gs;
1216         unsigned n_s;
1217         void *stash;
1218
1219         mem = sizeof(*uc);
1220         mem += sizeof(void *) * (n_gstrings + 1);
1221         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1222         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1223         uc = kmalloc(mem, GFP_KERNEL);
1224         if (!uc)
1225                 return ERR_PTR(-ENOMEM);
1226         gs_array = get_containers_gs(uc);
1227         stash = uc->stash;
1228         stash += sizeof(void *) * (n_gstrings + 1);
1229         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1230                 struct usb_string *org_s;
1231
1232                 gs_array[n_gs] = stash;
1233                 gs = gs_array[n_gs];
1234                 stash += sizeof(struct usb_gadget_strings);
1235                 gs->language = sp[n_gs]->language;
1236                 gs->strings = stash;
1237                 org_s = sp[n_gs]->strings;
1238
1239                 for (n_s = 0; n_s < n_strings; n_s++) {
1240                         s = stash;
1241                         stash += sizeof(struct usb_string);
1242                         if (org_s->s)
1243                                 s->s = org_s->s;
1244                         else
1245                                 s->s = "";
1246                         org_s++;
1247                 }
1248                 s = stash;
1249                 s->s = NULL;
1250                 stash += sizeof(struct usb_string);
1251
1252         }
1253         gs_array[n_gs] = NULL;
1254         return uc;
1255 }
1256
1257 /**
1258  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1259  * @cdev: the device whose string descriptor IDs are being allocated
1260  * and attached.
1261  * @sp: an array of usb_gadget_strings to attach.
1262  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1263  *
1264  * This function will create a deep copy of usb_gadget_strings and usb_string
1265  * and attach it to the cdev. The actual string (usb_string.s) will not be
1266  * copied but only a referenced will be made. The struct usb_gadget_strings
1267  * array may contain multiple languages and should be NULL terminated.
1268  * The ->language pointer of each struct usb_gadget_strings has to contain the
1269  * same amount of entries.
1270  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1271  * usb_string entry of es-ES contains the translation of the first usb_string
1272  * entry of en-US. Therefore both entries become the same id assign.
1273  */
1274 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1275                 struct usb_gadget_strings **sp, unsigned n_strings)
1276 {
1277         struct usb_gadget_string_container *uc;
1278         struct usb_gadget_strings **n_gs;
1279         unsigned n_gstrings = 0;
1280         unsigned i;
1281         int ret;
1282
1283         for (i = 0; sp[i]; i++)
1284                 n_gstrings++;
1285
1286         if (!n_gstrings)
1287                 return ERR_PTR(-EINVAL);
1288
1289         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1290         if (IS_ERR(uc))
1291                 return ERR_CAST(uc);
1292
1293         n_gs = get_containers_gs(uc);
1294         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1295         if (ret)
1296                 goto err;
1297
1298         for (i = 1; i < n_gstrings; i++) {
1299                 struct usb_string *m_s;
1300                 struct usb_string *s;
1301                 unsigned n;
1302
1303                 m_s = n_gs[0]->strings;
1304                 s = n_gs[i]->strings;
1305                 for (n = 0; n < n_strings; n++) {
1306                         s->id = m_s->id;
1307                         s++;
1308                         m_s++;
1309                 }
1310         }
1311         list_add_tail(&uc->list, &cdev->gstrings);
1312         return n_gs[0]->strings;
1313 err:
1314         kfree(uc);
1315         return ERR_PTR(ret);
1316 }
1317 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1318
1319 /**
1320  * usb_string_ids_n() - allocate unused string IDs in batch
1321  * @c: the device whose string descriptor IDs are being allocated
1322  * @n: number of string IDs to allocate
1323  * Context: single threaded during gadget setup
1324  *
1325  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1326  * valid IDs.  At least provided that @n is non-zero because if it
1327  * is, returns last requested ID which is now very useful information.
1328  *
1329  * @usb_string_ids_n() is called from bind() callbacks to allocate
1330  * string IDs.  Drivers for functions, configurations, or gadgets will
1331  * then store that ID in the appropriate descriptors and string table.
1332  *
1333  * All string identifier should be allocated using this,
1334  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1335  * example different functions don't wrongly assign different meanings
1336  * to the same identifier.
1337  */
1338 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1339 {
1340         unsigned next = c->next_string_id;
1341         if (unlikely(n > 254 || (unsigned)next + n > 254))
1342                 return -ENODEV;
1343         c->next_string_id += n;
1344         return next + 1;
1345 }
1346 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1347
1348 /*-------------------------------------------------------------------------*/
1349
1350 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1351 {
1352         struct usb_composite_dev *cdev;
1353
1354         if (req->status || req->actual != req->length)
1355                 DBG((struct usb_composite_dev *) ep->driver_data,
1356                                 "setup complete --> %d, %d/%d\n",
1357                                 req->status, req->actual, req->length);
1358
1359         /*
1360          * REVIST The same ep0 requests are shared with function drivers
1361          * so they don't have to maintain the same ->complete() stubs.
1362          *
1363          * Because of that, we need to check for the validity of ->context
1364          * here, even though we know we've set it to something useful.
1365          */
1366         if (!req->context)
1367                 return;
1368
1369         cdev = req->context;
1370
1371         if (cdev->req == req)
1372                 cdev->setup_pending = false;
1373         else if (cdev->os_desc_req == req)
1374                 cdev->os_desc_pending = false;
1375         else
1376                 WARN(1, "unknown request %p\n", req);
1377 }
1378
1379 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1380                 struct usb_request *req, gfp_t gfp_flags)
1381 {
1382         int ret;
1383
1384         ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1385         if (ret == 0) {
1386                 if (cdev->req == req)
1387                         cdev->setup_pending = true;
1388                 else if (cdev->os_desc_req == req)
1389                         cdev->os_desc_pending = true;
1390                 else
1391                         WARN(1, "unknown request %p\n", req);
1392         }
1393
1394         return ret;
1395 }
1396
1397 static int count_ext_compat(struct usb_configuration *c)
1398 {
1399         int i, res;
1400
1401         res = 0;
1402         for (i = 0; i < c->next_interface_id; ++i) {
1403                 struct usb_function *f;
1404                 int j;
1405
1406                 f = c->interface[i];
1407                 for (j = 0; j < f->os_desc_n; ++j) {
1408                         struct usb_os_desc *d;
1409
1410                         if (i != f->os_desc_table[j].if_id)
1411                                 continue;
1412                         d = f->os_desc_table[j].os_desc;
1413                         if (d && d->ext_compat_id)
1414                                 ++res;
1415                 }
1416         }
1417         BUG_ON(res > 255);
1418         return res;
1419 }
1420
1421 static void fill_ext_compat(struct usb_configuration *c, u8 *buf)
1422 {
1423         int i, count;
1424
1425         count = 16;
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                                 *buf++ = i;
1439                                 *buf++ = 0x01;
1440                                 memcpy(buf, d->ext_compat_id, 16);
1441                                 buf += 22;
1442                         } else {
1443                                 ++buf;
1444                                 *buf = 0x01;
1445                                 buf += 23;
1446                         }
1447                         count += 24;
1448                         if (count >= 4096)
1449                                 return;
1450                 }
1451         }
1452 }
1453
1454 static int count_ext_prop(struct usb_configuration *c, int interface)
1455 {
1456         struct usb_function *f;
1457         int j;
1458
1459         f = c->interface[interface];
1460         for (j = 0; j < f->os_desc_n; ++j) {
1461                 struct usb_os_desc *d;
1462
1463                 if (interface != f->os_desc_table[j].if_id)
1464                         continue;
1465                 d = f->os_desc_table[j].os_desc;
1466                 if (d && d->ext_compat_id)
1467                         return d->ext_prop_count;
1468         }
1469         return 0;
1470 }
1471
1472 static int len_ext_prop(struct usb_configuration *c, int interface)
1473 {
1474         struct usb_function *f;
1475         struct usb_os_desc *d;
1476         int j, res;
1477
1478         res = 10; /* header length */
1479         f = c->interface[interface];
1480         for (j = 0; j < f->os_desc_n; ++j) {
1481                 if (interface != f->os_desc_table[j].if_id)
1482                         continue;
1483                 d = f->os_desc_table[j].os_desc;
1484                 if (d)
1485                         return min(res + d->ext_prop_len, 4096);
1486         }
1487         return res;
1488 }
1489
1490 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1491 {
1492         struct usb_function *f;
1493         struct usb_os_desc *d;
1494         struct usb_os_desc_ext_prop *ext_prop;
1495         int j, count, n, ret;
1496         u8 *start = buf;
1497
1498         f = c->interface[interface];
1499         for (j = 0; j < f->os_desc_n; ++j) {
1500                 if (interface != f->os_desc_table[j].if_id)
1501                         continue;
1502                 d = f->os_desc_table[j].os_desc;
1503                 if (d)
1504                         list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1505                                 /* 4kB minus header length */
1506                                 n = buf - start;
1507                                 if (n >= 4086)
1508                                         return 0;
1509
1510                                 count = ext_prop->data_len +
1511                                         ext_prop->name_len + 14;
1512                                 if (count > 4086 - n)
1513                                         return -EINVAL;
1514                                 usb_ext_prop_put_size(buf, count);
1515                                 usb_ext_prop_put_type(buf, ext_prop->type);
1516                                 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1517                                                             ext_prop->name_len);
1518                                 if (ret < 0)
1519                                         return ret;
1520                                 switch (ext_prop->type) {
1521                                 case USB_EXT_PROP_UNICODE:
1522                                 case USB_EXT_PROP_UNICODE_ENV:
1523                                 case USB_EXT_PROP_UNICODE_LINK:
1524                                         usb_ext_prop_put_unicode(buf, ret,
1525                                                          ext_prop->data,
1526                                                          ext_prop->data_len);
1527                                         break;
1528                                 case USB_EXT_PROP_BINARY:
1529                                         usb_ext_prop_put_binary(buf, ret,
1530                                                         ext_prop->data,
1531                                                         ext_prop->data_len);
1532                                         break;
1533                                 case USB_EXT_PROP_LE32:
1534                                         /* not implemented */
1535                                 case USB_EXT_PROP_BE32:
1536                                         /* not implemented */
1537                                 default:
1538                                         return -EINVAL;
1539                                 }
1540                                 buf += count;
1541                         }
1542         }
1543
1544         return 0;
1545 }
1546
1547 /*
1548  * The setup() callback implements all the ep0 functionality that's
1549  * not handled lower down, in hardware or the hardware driver(like
1550  * device and endpoint feature flags, and their status).  It's all
1551  * housekeeping for the gadget function we're implementing.  Most of
1552  * the work is in config and function specific setup.
1553  */
1554 int
1555 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1556 {
1557         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1558         struct usb_request              *req = cdev->req;
1559         int                             value = -EOPNOTSUPP;
1560         int                             status = 0;
1561         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1562         u8                              intf = w_index & 0xFF;
1563         u16                             w_value = le16_to_cpu(ctrl->wValue);
1564         u16                             w_length = le16_to_cpu(ctrl->wLength);
1565         struct usb_function             *f = NULL;
1566         u8                              endp;
1567
1568         /* partial re-init of the response message; the function or the
1569          * gadget might need to intercept e.g. a control-OUT completion
1570          * when we delegate to it.
1571          */
1572         req->zero = 0;
1573         req->context = cdev;
1574         req->complete = composite_setup_complete;
1575         req->length = 0;
1576         gadget->ep0->driver_data = cdev;
1577
1578         /*
1579          * Don't let non-standard requests match any of the cases below
1580          * by accident.
1581          */
1582         if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1583                 goto unknown;
1584
1585         switch (ctrl->bRequest) {
1586
1587         /* we handle all standard USB descriptors */
1588         case USB_REQ_GET_DESCRIPTOR:
1589                 if (ctrl->bRequestType != USB_DIR_IN)
1590                         goto unknown;
1591                 switch (w_value >> 8) {
1592
1593                 case USB_DT_DEVICE:
1594                         cdev->desc.bNumConfigurations =
1595                                 count_configs(cdev, USB_DT_DEVICE);
1596                         cdev->desc.bMaxPacketSize0 =
1597                                 cdev->gadget->ep0->maxpacket;
1598                         if (gadget_is_superspeed(gadget)) {
1599                                 if (gadget->speed >= USB_SPEED_SUPER) {
1600                                         cdev->desc.bcdUSB = cpu_to_le16(0x0310);
1601                                         cdev->desc.bMaxPacketSize0 = 9;
1602                                 } else {
1603                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1604                                 }
1605                         } else {
1606                                 cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1607                         }
1608
1609                         value = min(w_length, (u16) sizeof cdev->desc);
1610                         memcpy(req->buf, &cdev->desc, value);
1611                         break;
1612                 case USB_DT_DEVICE_QUALIFIER:
1613                         if (!gadget_is_dualspeed(gadget) ||
1614                             gadget->speed >= USB_SPEED_SUPER)
1615                                 break;
1616                         device_qual(cdev);
1617                         value = min_t(int, w_length,
1618                                 sizeof(struct usb_qualifier_descriptor));
1619                         break;
1620                 case USB_DT_OTHER_SPEED_CONFIG:
1621                         if (!gadget_is_dualspeed(gadget) ||
1622                             gadget->speed >= USB_SPEED_SUPER)
1623                                 break;
1624                         /* FALLTHROUGH */
1625                 case USB_DT_CONFIG:
1626                         value = config_desc(cdev, w_value);
1627                         if (value >= 0)
1628                                 value = min(w_length, (u16) value);
1629                         break;
1630                 case USB_DT_STRING:
1631                         value = get_string(cdev, req->buf,
1632                                         w_index, w_value & 0xff);
1633                         if (value >= 0)
1634                                 value = min(w_length, (u16) value);
1635                         break;
1636                 case USB_DT_BOS:
1637                         if (gadget_is_superspeed(gadget)) {
1638                                 value = bos_desc(cdev);
1639                                 value = min(w_length, (u16) value);
1640                         }
1641                         break;
1642                 case USB_DT_OTG:
1643                         if (gadget_is_otg(gadget)) {
1644                                 struct usb_configuration *config;
1645                                 int otg_desc_len = 0;
1646
1647                                 if (cdev->config)
1648                                         config = cdev->config;
1649                                 else
1650                                         config = list_first_entry(
1651                                                         &cdev->configs,
1652                                                 struct usb_configuration, list);
1653                                 if (!config)
1654                                         goto done;
1655
1656                                 if (gadget->otg_caps &&
1657                                         (gadget->otg_caps->otg_rev >= 0x0200))
1658                                         otg_desc_len += sizeof(
1659                                                 struct usb_otg20_descriptor);
1660                                 else
1661                                         otg_desc_len += sizeof(
1662                                                 struct usb_otg_descriptor);
1663
1664                                 value = min_t(int, w_length, otg_desc_len);
1665                                 memcpy(req->buf, config->descriptors[0], value);
1666                         }
1667                         break;
1668                 }
1669                 break;
1670
1671         /* any number of configs can work */
1672         case USB_REQ_SET_CONFIGURATION:
1673                 if (ctrl->bRequestType != 0)
1674                         goto unknown;
1675                 if (gadget_is_otg(gadget)) {
1676                         if (gadget->a_hnp_support)
1677                                 DBG(cdev, "HNP available\n");
1678                         else if (gadget->a_alt_hnp_support)
1679                                 DBG(cdev, "HNP on another port\n");
1680                         else
1681                                 VDBG(cdev, "HNP inactive\n");
1682                 }
1683                 spin_lock(&cdev->lock);
1684                 value = set_config(cdev, ctrl, w_value);
1685                 spin_unlock(&cdev->lock);
1686                 break;
1687         case USB_REQ_GET_CONFIGURATION:
1688                 if (ctrl->bRequestType != USB_DIR_IN)
1689                         goto unknown;
1690                 if (cdev->config)
1691                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1692                 else
1693                         *(u8 *)req->buf = 0;
1694                 value = min(w_length, (u16) 1);
1695                 break;
1696
1697         /* function drivers must handle get/set altsetting */
1698         case USB_REQ_SET_INTERFACE:
1699                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1700                         goto unknown;
1701                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1702                         break;
1703                 f = cdev->config->interface[intf];
1704                 if (!f)
1705                         break;
1706
1707                 /*
1708                  * If there's no get_alt() method, we know only altsetting zero
1709                  * works. There is no need to check if set_alt() is not NULL
1710                  * as we check this in usb_add_function().
1711                  */
1712                 if (w_value && !f->get_alt)
1713                         break;
1714                 value = f->set_alt(f, w_index, w_value);
1715                 if (value == USB_GADGET_DELAYED_STATUS) {
1716                         DBG(cdev,
1717                          "%s: interface %d (%s) requested delayed status\n",
1718                                         __func__, intf, f->name);
1719                         cdev->delayed_status++;
1720                         DBG(cdev, "delayed_status count %d\n",
1721                                         cdev->delayed_status);
1722                 }
1723                 break;
1724         case USB_REQ_GET_INTERFACE:
1725                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1726                         goto unknown;
1727                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1728                         break;
1729                 f = cdev->config->interface[intf];
1730                 if (!f)
1731                         break;
1732                 /* lots of interfaces only need altsetting zero... */
1733                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1734                 if (value < 0)
1735                         break;
1736                 *((u8 *)req->buf) = value;
1737                 value = min(w_length, (u16) 1);
1738                 break;
1739         case USB_REQ_GET_STATUS:
1740                 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1741                                                 (w_index == OTG_STS_SELECTOR)) {
1742                         if (ctrl->bRequestType != (USB_DIR_IN |
1743                                                         USB_RECIP_DEVICE))
1744                                 goto unknown;
1745                         *((u8 *)req->buf) = gadget->host_request_flag;
1746                         value = 1;
1747                         break;
1748                 }
1749
1750                 /*
1751                  * USB 3.0 additions:
1752                  * Function driver should handle get_status request. If such cb
1753                  * wasn't supplied we respond with default value = 0
1754                  * Note: function driver should supply such cb only for the
1755                  * first interface of the function
1756                  */
1757                 if (!gadget_is_superspeed(gadget))
1758                         goto unknown;
1759                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1760                         goto unknown;
1761                 value = 2;      /* This is the length of the get_status reply */
1762                 put_unaligned_le16(0, req->buf);
1763                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1764                         break;
1765                 f = cdev->config->interface[intf];
1766                 if (!f)
1767                         break;
1768                 status = f->get_status ? f->get_status(f) : 0;
1769                 if (status < 0)
1770                         break;
1771                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1772                 break;
1773         /*
1774          * Function drivers should handle SetFeature/ClearFeature
1775          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1776          * only for the first interface of the function
1777          */
1778         case USB_REQ_CLEAR_FEATURE:
1779         case USB_REQ_SET_FEATURE:
1780                 if (!gadget_is_superspeed(gadget))
1781                         goto unknown;
1782                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1783                         goto unknown;
1784                 switch (w_value) {
1785                 case USB_INTRF_FUNC_SUSPEND:
1786                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1787                                 break;
1788                         f = cdev->config->interface[intf];
1789                         if (!f)
1790                                 break;
1791                         value = 0;
1792                         if (f->func_suspend)
1793                                 value = f->func_suspend(f, w_index >> 8);
1794                         if (value < 0) {
1795                                 ERROR(cdev,
1796                                       "func_suspend() returned error %d\n",
1797                                       value);
1798                                 value = 0;
1799                         }
1800                         break;
1801                 }
1802                 break;
1803         default:
1804 unknown:
1805                 /*
1806                  * OS descriptors handling
1807                  */
1808                 if (cdev->use_os_string && cdev->os_desc_config &&
1809                     (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1810                     ctrl->bRequest == cdev->b_vendor_code) {
1811                         struct usb_request              *req;
1812                         struct usb_configuration        *os_desc_cfg;
1813                         u8                              *buf;
1814                         int                             interface;
1815                         int                             count = 0;
1816
1817                         req = cdev->os_desc_req;
1818                         req->context = cdev;
1819                         req->complete = composite_setup_complete;
1820                         buf = req->buf;
1821                         os_desc_cfg = cdev->os_desc_config;
1822                         memset(buf, 0, w_length);
1823                         buf[5] = 0x01;
1824                         switch (ctrl->bRequestType & USB_RECIP_MASK) {
1825                         case USB_RECIP_DEVICE:
1826                                 if (w_index != 0x4 || (w_value >> 8))
1827                                         break;
1828                                 buf[6] = w_index;
1829                                 if (w_length == 0x10) {
1830                                         /* Number of ext compat interfaces */
1831                                         count = count_ext_compat(os_desc_cfg);
1832                                         buf[8] = count;
1833                                         count *= 24; /* 24 B/ext compat desc */
1834                                         count += 16; /* header */
1835                                         put_unaligned_le32(count, buf);
1836                                         value = w_length;
1837                                 } else {
1838                                         /* "extended compatibility ID"s */
1839                                         count = count_ext_compat(os_desc_cfg);
1840                                         buf[8] = count;
1841                                         count *= 24; /* 24 B/ext compat desc */
1842                                         count += 16; /* header */
1843                                         put_unaligned_le32(count, buf);
1844                                         buf += 16;
1845                                         fill_ext_compat(os_desc_cfg, buf);
1846                                         value = w_length;
1847                                 }
1848                                 break;
1849                         case USB_RECIP_INTERFACE:
1850                                 if (w_index != 0x5 || (w_value >> 8))
1851                                         break;
1852                                 interface = w_value & 0xFF;
1853                                 buf[6] = w_index;
1854                                 if (w_length == 0x0A) {
1855                                         count = count_ext_prop(os_desc_cfg,
1856                                                 interface);
1857                                         put_unaligned_le16(count, buf + 8);
1858                                         count = len_ext_prop(os_desc_cfg,
1859                                                 interface);
1860                                         put_unaligned_le32(count, buf);
1861
1862                                         value = w_length;
1863                                 } else {
1864                                         count = count_ext_prop(os_desc_cfg,
1865                                                 interface);
1866                                         put_unaligned_le16(count, buf + 8);
1867                                         count = len_ext_prop(os_desc_cfg,
1868                                                 interface);
1869                                         put_unaligned_le32(count, buf);
1870                                         buf += 10;
1871                                         value = fill_ext_prop(os_desc_cfg,
1872                                                               interface, buf);
1873                                         if (value < 0)
1874                                                 return value;
1875
1876                                         value = w_length;
1877                                 }
1878                                 break;
1879                         }
1880
1881                         if (value >= 0) {
1882                                 req->length = value;
1883                                 req->context = cdev;
1884                                 req->zero = value < w_length;
1885                                 value = composite_ep0_queue(cdev, req,
1886                                                             GFP_ATOMIC);
1887                                 if (value < 0) {
1888                                         DBG(cdev, "ep_queue --> %d\n", value);
1889                                         req->status = 0;
1890                                         composite_setup_complete(gadget->ep0,
1891                                                                  req);
1892                                 }
1893                         }
1894                         return value;
1895                 }
1896
1897                 VDBG(cdev,
1898                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1899                         ctrl->bRequestType, ctrl->bRequest,
1900                         w_value, w_index, w_length);
1901
1902                 /* functions always handle their interfaces and endpoints...
1903                  * punt other recipients (other, WUSB, ...) to the current
1904                  * configuration code.
1905                  */
1906                 if (cdev->config) {
1907                         list_for_each_entry(f, &cdev->config->functions, list)
1908                                 if (f->req_match &&
1909                                     f->req_match(f, ctrl, false))
1910                                         goto try_fun_setup;
1911                 } else {
1912                         struct usb_configuration *c;
1913                         list_for_each_entry(c, &cdev->configs, list)
1914                                 list_for_each_entry(f, &c->functions, list)
1915                                         if (f->req_match &&
1916                                             f->req_match(f, ctrl, true))
1917                                                 goto try_fun_setup;
1918                 }
1919                 f = NULL;
1920
1921                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1922                 case USB_RECIP_INTERFACE:
1923                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1924                                 break;
1925                         f = cdev->config->interface[intf];
1926                         break;
1927
1928                 case USB_RECIP_ENDPOINT:
1929                         if (!cdev->config)
1930                                 break;
1931                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1932                         list_for_each_entry(f, &cdev->config->functions, list) {
1933                                 if (test_bit(endp, f->endpoints))
1934                                         break;
1935                         }
1936                         if (&f->list == &cdev->config->functions)
1937                                 f = NULL;
1938                         break;
1939                 }
1940 try_fun_setup:
1941                 if (f && f->setup)
1942                         value = f->setup(f, ctrl);
1943                 else {
1944                         struct usb_configuration        *c;
1945
1946                         c = cdev->config;
1947                         if (!c)
1948                                 goto done;
1949
1950                         /* try current config's setup */
1951                         if (c->setup) {
1952                                 value = c->setup(c, ctrl);
1953                                 goto done;
1954                         }
1955
1956                         /* try the only function in the current config */
1957                         if (!list_is_singular(&c->functions))
1958                                 goto done;
1959                         f = list_first_entry(&c->functions, struct usb_function,
1960                                              list);
1961                         if (f->setup)
1962                                 value = f->setup(f, ctrl);
1963                 }
1964
1965                 goto done;
1966         }
1967
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         if (cdev->config)
2000                 reset_config(cdev);
2001         if (cdev->driver->disconnect)
2002                 cdev->driver->disconnect(cdev);
2003         spin_unlock_irqrestore(&cdev->lock, flags);
2004 }
2005
2006 /*-------------------------------------------------------------------------*/
2007
2008 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2009                               char *buf)
2010 {
2011         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2012         struct usb_composite_dev *cdev = get_gadget_data(gadget);
2013
2014         return sprintf(buf, "%d\n", cdev->suspended);
2015 }
2016 static DEVICE_ATTR_RO(suspended);
2017
2018 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2019 {
2020         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2021
2022         /* composite_disconnect() must already have been called
2023          * by the underlying peripheral controller driver!
2024          * so there's no i/o concurrency that could affect the
2025          * state protected by cdev->lock.
2026          */
2027         WARN_ON(cdev->config);
2028
2029         while (!list_empty(&cdev->configs)) {
2030                 struct usb_configuration        *c;
2031                 c = list_first_entry(&cdev->configs,
2032                                 struct usb_configuration, list);
2033                 remove_config(cdev, c);
2034         }
2035         if (cdev->driver->unbind && unbind_driver)
2036                 cdev->driver->unbind(cdev);
2037
2038         composite_dev_cleanup(cdev);
2039
2040         kfree(cdev->def_manufacturer);
2041         kfree(cdev);
2042         set_gadget_data(gadget, NULL);
2043 }
2044
2045 static void composite_unbind(struct usb_gadget *gadget)
2046 {
2047         __composite_unbind(gadget, true);
2048 }
2049
2050 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2051                 const struct usb_device_descriptor *old)
2052 {
2053         __le16 idVendor;
2054         __le16 idProduct;
2055         __le16 bcdDevice;
2056         u8 iSerialNumber;
2057         u8 iManufacturer;
2058         u8 iProduct;
2059
2060         /*
2061          * these variables may have been set in
2062          * usb_composite_overwrite_options()
2063          */
2064         idVendor = new->idVendor;
2065         idProduct = new->idProduct;
2066         bcdDevice = new->bcdDevice;
2067         iSerialNumber = new->iSerialNumber;
2068         iManufacturer = new->iManufacturer;
2069         iProduct = new->iProduct;
2070
2071         *new = *old;
2072         if (idVendor)
2073                 new->idVendor = idVendor;
2074         if (idProduct)
2075                 new->idProduct = idProduct;
2076         if (bcdDevice)
2077                 new->bcdDevice = bcdDevice;
2078         else
2079                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2080         if (iSerialNumber)
2081                 new->iSerialNumber = iSerialNumber;
2082         if (iManufacturer)
2083                 new->iManufacturer = iManufacturer;
2084         if (iProduct)
2085                 new->iProduct = iProduct;
2086 }
2087
2088 int composite_dev_prepare(struct usb_composite_driver *composite,
2089                 struct usb_composite_dev *cdev)
2090 {
2091         struct usb_gadget *gadget = cdev->gadget;
2092         int ret = -ENOMEM;
2093
2094         /* preallocate control response and buffer */
2095         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2096         if (!cdev->req)
2097                 return -ENOMEM;
2098
2099         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2100         if (!cdev->req->buf)
2101                 goto fail;
2102
2103         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2104         if (ret)
2105                 goto fail_dev;
2106
2107         cdev->req->complete = composite_setup_complete;
2108         cdev->req->context = cdev;
2109         gadget->ep0->driver_data = cdev;
2110
2111         cdev->driver = composite;
2112
2113         /*
2114          * As per USB compliance update, a device that is actively drawing
2115          * more than 100mA from USB must report itself as bus-powered in
2116          * the GetStatus(DEVICE) call.
2117          */
2118         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2119                 usb_gadget_set_selfpowered(gadget);
2120
2121         /* interface and string IDs start at zero via kzalloc.
2122          * we force endpoints to start unassigned; few controller
2123          * drivers will zero ep->driver_data.
2124          */
2125         usb_ep_autoconfig_reset(gadget);
2126         return 0;
2127 fail_dev:
2128         kfree(cdev->req->buf);
2129 fail:
2130         usb_ep_free_request(gadget->ep0, cdev->req);
2131         cdev->req = NULL;
2132         return ret;
2133 }
2134
2135 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2136                                   struct usb_ep *ep0)
2137 {
2138         int ret = 0;
2139
2140         cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2141         if (!cdev->os_desc_req) {
2142                 ret = -ENOMEM;
2143                 goto end;
2144         }
2145
2146         /* OS feature descriptor length <= 4kB */
2147         cdev->os_desc_req->buf = kmalloc(4096, GFP_KERNEL);
2148         if (!cdev->os_desc_req->buf) {
2149                 ret = -ENOMEM;
2150                 kfree(cdev->os_desc_req);
2151                 goto end;
2152         }
2153         cdev->os_desc_req->context = cdev;
2154         cdev->os_desc_req->complete = composite_setup_complete;
2155 end:
2156         return ret;
2157 }
2158
2159 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2160 {
2161         struct usb_gadget_string_container *uc, *tmp;
2162
2163         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2164                 list_del(&uc->list);
2165                 kfree(uc);
2166         }
2167         if (cdev->os_desc_req) {
2168                 if (cdev->os_desc_pending)
2169                         usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2170
2171                 kfree(cdev->os_desc_req->buf);
2172                 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2173         }
2174         if (cdev->req) {
2175                 if (cdev->setup_pending)
2176                         usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2177
2178                 kfree(cdev->req->buf);
2179                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2180         }
2181         cdev->next_string_id = 0;
2182         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2183 }
2184
2185 static int composite_bind(struct usb_gadget *gadget,
2186                 struct usb_gadget_driver *gdriver)
2187 {
2188         struct usb_composite_dev        *cdev;
2189         struct usb_composite_driver     *composite = to_cdriver(gdriver);
2190         int                             status = -ENOMEM;
2191
2192         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2193         if (!cdev)
2194                 return status;
2195
2196         spin_lock_init(&cdev->lock);
2197         cdev->gadget = gadget;
2198         set_gadget_data(gadget, cdev);
2199         INIT_LIST_HEAD(&cdev->configs);
2200         INIT_LIST_HEAD(&cdev->gstrings);
2201
2202         status = composite_dev_prepare(composite, cdev);
2203         if (status)
2204                 goto fail;
2205
2206         /* composite gadget needs to assign strings for whole device (like
2207          * serial number), register function drivers, potentially update
2208          * power state and consumption, etc
2209          */
2210         status = composite->bind(cdev);
2211         if (status < 0)
2212                 goto fail;
2213
2214         if (cdev->use_os_string) {
2215                 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2216                 if (status)
2217                         goto fail;
2218         }
2219
2220         update_unchanged_dev_desc(&cdev->desc, composite->dev);
2221
2222         /* has userspace failed to provide a serial number? */
2223         if (composite->needs_serial && !cdev->desc.iSerialNumber)
2224                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2225
2226         INFO(cdev, "%s ready\n", composite->name);
2227         return 0;
2228
2229 fail:
2230         __composite_unbind(gadget, false);
2231         return status;
2232 }
2233
2234 /*-------------------------------------------------------------------------*/
2235
2236 void composite_suspend(struct usb_gadget *gadget)
2237 {
2238         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2239         struct usb_function             *f;
2240
2241         /* REVISIT:  should we have config level
2242          * suspend/resume callbacks?
2243          */
2244         DBG(cdev, "suspend\n");
2245         if (cdev->config) {
2246                 list_for_each_entry(f, &cdev->config->functions, list) {
2247                         if (f->suspend)
2248                                 f->suspend(f);
2249                 }
2250         }
2251         if (cdev->driver->suspend)
2252                 cdev->driver->suspend(cdev);
2253
2254         cdev->suspended = 1;
2255
2256         usb_gadget_vbus_draw(gadget, 2);
2257 }
2258
2259 void composite_resume(struct usb_gadget *gadget)
2260 {
2261         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
2262         struct usb_function             *f;
2263         u16                             maxpower;
2264
2265         /* REVISIT:  should we have config level
2266          * suspend/resume callbacks?
2267          */
2268         DBG(cdev, "resume\n");
2269         if (cdev->driver->resume)
2270                 cdev->driver->resume(cdev);
2271         if (cdev->config) {
2272                 list_for_each_entry(f, &cdev->config->functions, list) {
2273                         if (f->resume)
2274                                 f->resume(f);
2275                 }
2276
2277                 maxpower = cdev->config->MaxPower;
2278
2279                 usb_gadget_vbus_draw(gadget, maxpower ?
2280                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
2281         }
2282
2283         cdev->suspended = 0;
2284 }
2285
2286 /*-------------------------------------------------------------------------*/
2287
2288 static const struct usb_gadget_driver composite_driver_template = {
2289         .bind           = composite_bind,
2290         .unbind         = composite_unbind,
2291
2292         .setup          = composite_setup,
2293         .reset          = composite_disconnect,
2294         .disconnect     = composite_disconnect,
2295
2296         .suspend        = composite_suspend,
2297         .resume         = composite_resume,
2298
2299         .driver = {
2300                 .owner          = THIS_MODULE,
2301         },
2302 };
2303
2304 /**
2305  * usb_composite_probe() - register a composite driver
2306  * @driver: the driver to register
2307  *
2308  * Context: single threaded during gadget setup
2309  *
2310  * This function is used to register drivers using the composite driver
2311  * framework.  The return value is zero, or a negative errno value.
2312  * Those values normally come from the driver's @bind method, which does
2313  * all the work of setting up the driver to match the hardware.
2314  *
2315  * On successful return, the gadget is ready to respond to requests from
2316  * the host, unless one of its components invokes usb_gadget_disconnect()
2317  * while it was binding.  That would usually be done in order to wait for
2318  * some userspace participation.
2319  */
2320 int usb_composite_probe(struct usb_composite_driver *driver)
2321 {
2322         struct usb_gadget_driver *gadget_driver;
2323
2324         if (!driver || !driver->dev || !driver->bind)
2325                 return -EINVAL;
2326
2327         if (!driver->name)
2328                 driver->name = "composite";
2329
2330         driver->gadget_driver = composite_driver_template;
2331         gadget_driver = &driver->gadget_driver;
2332
2333         gadget_driver->function =  (char *) driver->name;
2334         gadget_driver->driver.name = driver->name;
2335         gadget_driver->max_speed = driver->max_speed;
2336
2337         return usb_gadget_probe_driver(gadget_driver);
2338 }
2339 EXPORT_SYMBOL_GPL(usb_composite_probe);
2340
2341 /**
2342  * usb_composite_unregister() - unregister a composite driver
2343  * @driver: the driver to unregister
2344  *
2345  * This function is used to unregister drivers using the composite
2346  * driver framework.
2347  */
2348 void usb_composite_unregister(struct usb_composite_driver *driver)
2349 {
2350         usb_gadget_unregister_driver(&driver->gadget_driver);
2351 }
2352 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2353
2354 /**
2355  * usb_composite_setup_continue() - Continue with the control transfer
2356  * @cdev: the composite device who's control transfer was kept waiting
2357  *
2358  * This function must be called by the USB function driver to continue
2359  * with the control transfer's data/status stage in case it had requested to
2360  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2361  * can request the composite framework to delay the setup request's data/status
2362  * stages by returning USB_GADGET_DELAYED_STATUS.
2363  */
2364 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2365 {
2366         int                     value;
2367         struct usb_request      *req = cdev->req;
2368         unsigned long           flags;
2369
2370         DBG(cdev, "%s\n", __func__);
2371         spin_lock_irqsave(&cdev->lock, flags);
2372
2373         if (cdev->delayed_status == 0) {
2374                 WARN(cdev, "%s: Unexpected call\n", __func__);
2375
2376         } else if (--cdev->delayed_status == 0) {
2377                 DBG(cdev, "%s: Completing delayed status\n", __func__);
2378                 req->length = 0;
2379                 req->context = cdev;
2380                 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2381                 if (value < 0) {
2382                         DBG(cdev, "ep_queue --> %d\n", value);
2383                         req->status = 0;
2384                         composite_setup_complete(cdev->gadget->ep0, req);
2385                 }
2386         }
2387
2388         spin_unlock_irqrestore(&cdev->lock, flags);
2389 }
2390 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2391
2392 static char *composite_default_mfr(struct usb_gadget *gadget)
2393 {
2394         char *mfr;
2395         int len;
2396
2397         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
2398                         init_utsname()->release, gadget->name);
2399         len++;
2400         mfr = kmalloc(len, GFP_KERNEL);
2401         if (!mfr)
2402                 return NULL;
2403         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
2404                         init_utsname()->release, gadget->name);
2405         return mfr;
2406 }
2407
2408 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2409                 struct usb_composite_overwrite *covr)
2410 {
2411         struct usb_device_descriptor    *desc = &cdev->desc;
2412         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
2413         struct usb_string               *dev_str = gstr->strings;
2414
2415         if (covr->idVendor)
2416                 desc->idVendor = cpu_to_le16(covr->idVendor);
2417
2418         if (covr->idProduct)
2419                 desc->idProduct = cpu_to_le16(covr->idProduct);
2420
2421         if (covr->bcdDevice)
2422                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2423
2424         if (covr->serial_number) {
2425                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2426                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2427         }
2428         if (covr->manufacturer) {
2429                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2430                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2431
2432         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2433                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2434                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2435                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2436         }
2437
2438         if (covr->product) {
2439                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2440                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2441         }
2442 }
2443 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2444
2445 MODULE_LICENSE("GPL");
2446 MODULE_AUTHOR("David Brownell");