drivers/usb/gadget/composite.c

   1 /*
   2  * composite.c - infrastructure for Composite USB Gadgets
   3  *
   4  * Copyright (C) 2006-2008 David Brownell
   5  * Copyright (c) 2015 NVIDIA CORPORATION. All rights reserved.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 /* #define VERBOSE_DEBUG */
  14
  15 #include <linux/kallsyms.h>
  16 #include <linux/kernel.h>
  17 #include <linux/slab.h>
  18 #include <linux/module.h>
  19 #include <linux/device.h>
  20 #include <linux/utsname.h>
  21
  22 #include <linux/usb/composite.h>
  23 #include <asm/unaligned.h>
  24
  25 /*
  26  * The code in this file is utility code, used to build a gadget driver
  27  * from one or more "function" drivers, one or more "configuration"
  28  * objects, and a "usb_composite_driver" by gluing them together along
  29  * with the relevant device-wide data.
  30  */
  31
  32 static struct usb_gadget_strings **get_containers_gs(
  33                 struct usb_gadget_string_container *uc)
  34 {
  35         return (struct usb_gadget_strings **)uc->stash;
  36 }
  37
  38 /**
  39  * next_ep_desc() - advance to the next EP descriptor
  40  * @t: currect pointer within descriptor array
  41  *
  42  * Return: next EP descriptor or NULL
  43  *
  44  * Iterate over @t until either EP descriptor found or
  45  * NULL (that indicates end of list) encountered
  46  */
  47 static struct usb_descriptor_header**
  48 next_ep_desc(struct usb_descriptor_header **t)
  49 {
  50         for (; *t; t++) {
  51                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
  52                         return t;
  53         }
  54         return NULL;
  55 }
  56
  57 /*
  58  * for_each_ep_desc()- iterate over endpoint descriptors in the
  59  *              descriptors list
  60  * @start:      pointer within descriptor array.
  61  * @ep_desc:    endpoint descriptor to use as the loop cursor
  62  */
  63 #define for_each_ep_desc(start, ep_desc) \
  64         for (ep_desc = next_ep_desc(start); \
  65               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
  66
  67 /**
  68  * config_ep_by_speed() - configures the given endpoint
  69  * according to gadget speed.
  70  * @g: pointer to the gadget
  71  * @f: usb function
  72  * @_ep: the endpoint to configure
  73  *
  74  * Return: error code, 0 on success
  75  *
  76  * This function chooses the right descriptors for a given
  77  * endpoint according to gadget speed and saves it in the
  78  * endpoint desc field. If the endpoint already has a descriptor
  79  * assigned to it - overwrites it with currently corresponding
  80  * descriptor. The endpoint maxpacket field is updated according
  81  * to the chosen descriptor.
  82  * Note: the supplied function should hold all the descriptors
  83  * for supported speeds
  84  */
  85 int config_ep_by_speed(struct usb_gadget *g,
  86                         struct usb_function *f,
  87                         struct usb_ep *_ep)
  88 {
  89         struct usb_composite_dev        *cdev = get_gadget_data(g);
  90         struct usb_endpoint_descriptor *chosen_desc = NULL;
  91         struct usb_descriptor_header **speed_desc = NULL;
  92
  93         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
  94         int want_comp_desc = 0;
  95
  96         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
  97
  98         if (!g || !f || !_ep)
  99                 return -EIO;
 100
 101         /* select desired speed */
 102         switch (g->speed) {
 103         case USB_SPEED_SUPER:
 104                 if (gadget_is_superspeed(g)) {
 105                         speed_desc = f->ss_descriptors;
 106                         want_comp_desc = 1;
 107                         break;
 108                 }
 109                 /* else: Fall trough */
 110         case USB_SPEED_HIGH:
 111                 if (gadget_is_dualspeed(g)) {
 112                         speed_desc = f->hs_descriptors;
 113                         break;
 114                 }
 115                 /* else: fall through */
 116         default:
 117                 speed_desc = f->fs_descriptors;
 118         }
 119         /* find descriptors */
 120         for_each_ep_desc(speed_desc, d_spd) {
 121                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 122                 if (chosen_desc->bEndpointAddress == _ep->address)
 123                         goto ep_found;
 124         }
 125         return -EIO;
 126
 127 ep_found:
 128         /* commit results */
 129         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 130         _ep->desc = chosen_desc;
 131         _ep->comp_desc = NULL;
 132         _ep->maxburst = 0;
 133         _ep->mult = 0;
 134         if (!want_comp_desc)
 135                 return 0;
 136
 137         /*
 138          * Companion descriptor should follow EP descriptor
 139          * USB 3.0 spec, #9.6.7
 140          */
 141         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 142         if (!comp_desc ||
 143             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 144                 return -EIO;
 145         _ep->comp_desc = comp_desc;
 146         if (g->speed == USB_SPEED_SUPER) {
 147                 switch (usb_endpoint_type(_ep->desc)) {
 148                 case USB_ENDPOINT_XFER_ISOC:
 149                         /* mult: bits 1:0 of bmAttributes */
 150                         _ep->mult = comp_desc->bmAttributes & 0x3;
 151                 case USB_ENDPOINT_XFER_BULK:
 152                 case USB_ENDPOINT_XFER_INT:
 153                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 154                         break;
 155                 default:
 156                         if (comp_desc->bMaxBurst != 0)
 157                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 158                         _ep->maxburst = 1;
 159                         break;
 160                 }
 161         }
 162         return 0;
 163 }
 164 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 165
 166 /**
 167  * usb_add_function() - add a function to a configuration
 168  * @config: the configuration
 169  * @function: the function being added
 170  * Context: single threaded during gadget setup
 171  *
 172  * After initialization, each configuration must have one or more
 173  * functions added to it.  Adding a function involves calling its @bind()
 174  * method to allocate resources such as interface and string identifiers
 175  * and endpoints.
 176  *
 177  * This function returns the value of the function's bind(), which is
 178  * zero for success else a negative errno value.
 179  */
 180 int usb_add_function(struct usb_configuration *config,
 181                 struct usb_function *function)
 182 {
 183         int     value = -EINVAL;
 184
 185         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 186                         function->name, function,
 187                         config->label, config);
 188
 189         if (!function->set_alt || !function->disable)
 190                 goto done;
 191
 192         function->config = config;
 193         list_add_tail(&function->list, &config->functions);
 194
 195         /* REVISIT *require* function->bind? */
 196         if (function->bind) {
 197                 value = function->bind(config, function);
 198                 if (value < 0) {
 199                         list_del(&function->list);
 200                         function->config = NULL;
 201                 }
 202         } else
 203                 value = 0;
 204
 205         /* We allow configurations that don't work at both speeds.
 206          * If we run into a lowspeed Linux system, treat it the same
 207          * as full speed ... it's the function drivers that will need
 208          * to avoid bulk and ISO transfers.
 209          */
 210         if (!config->fullspeed && function->fs_descriptors)
 211                 config->fullspeed = true;
 212         if (!config->highspeed && function->hs_descriptors)
 213                 config->highspeed = true;
 214         if (!config->superspeed && function->ss_descriptors)
 215                 config->superspeed = true;
 216
 217 done:
 218         if (value)
 219                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 220                                 function->name, function, value);
 221         return value;
 222 }
 223 EXPORT_SYMBOL_GPL(usb_add_function);
 224
 225 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 226 {
 227         if (f->disable)
 228                 f->disable(f);
 229
 230         bitmap_zero(f->endpoints, 32);
 231         list_del(&f->list);
 232         if (f->unbind)
 233                 f->unbind(c, f);
 234 }
 235 EXPORT_SYMBOL_GPL(usb_remove_function);
 236
 237 /**
 238  * usb_function_deactivate - prevent function and gadget enumeration
 239  * @function: the function that isn't yet ready to respond
 240  *
 241  * Blocks response of the gadget driver to host enumeration by
 242  * preventing the data line pullup from being activated.  This is
 243  * normally called during @bind() processing to change from the
 244  * initial "ready to respond" state, or when a required resource
 245  * becomes available.
 246  *
 247  * For example, drivers that serve as a passthrough to a userspace
 248  * daemon can block enumeration unless that daemon (such as an OBEX,
 249  * MTP, or print server) is ready to handle host requests.
 250  *
 251  * Not all systems support software control of their USB peripheral
 252  * data pullups.
 253  *
 254  * Returns zero on success, else negative errno.
 255  */
 256 int usb_function_deactivate(struct usb_function *function)
 257 {
 258         struct usb_composite_dev        *cdev = function->config->cdev;
 259         unsigned long                   flags;
 260         int                             status = 0;
 261
 262         spin_lock_irqsave(&cdev->lock, flags);
 263
 264         if (cdev->deactivations == 0)
 265                 status = usb_gadget_disconnect(cdev->gadget);
 266         if (status == 0)
 267                 cdev->deactivations++;
 268
 269         spin_unlock_irqrestore(&cdev->lock, flags);
 270         return status;
 271 }
 272 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 273
 274 /**
 275  * usb_function_activate - allow function and gadget enumeration
 276  * @function: function on which usb_function_activate() was called
 277  *
 278  * Reverses effect of usb_function_deactivate().  If no more functions
 279  * are delaying their activation, the gadget driver will respond to
 280  * host enumeration procedures.
 281  *
 282  * Returns zero on success, else negative errno.
 283  */
 284 int usb_function_activate(struct usb_function *function)
 285 {
 286         struct usb_composite_dev        *cdev = function->config->cdev;
 287         unsigned long                   flags;
 288         int                             status = 0;
 289
 290         spin_lock_irqsave(&cdev->lock, flags);
 291
 292         if (WARN_ON(cdev->deactivations == 0))
 293                 status = -EINVAL;
 294         else {
 295                 cdev->deactivations--;
 296                 if (cdev->deactivations == 0)
 297                         status = usb_gadget_connect(cdev->gadget);
 298         }
 299
 300         spin_unlock_irqrestore(&cdev->lock, flags);
 301         return status;
 302 }
 303 EXPORT_SYMBOL_GPL(usb_function_activate);
 304
 305 /**
 306  * usb_interface_id() - allocate an unused interface ID
 307  * @config: configuration associated with the interface
 308  * @function: function handling the interface
 309  * Context: single threaded during gadget setup
 310  *
 311  * usb_interface_id() is called from usb_function.bind() callbacks to
 312  * allocate new interface IDs.  The function driver will then store that
 313  * ID in interface, association, CDC union, and other descriptors.  It
 314  * will also handle any control requests targeted at that interface,
 315  * particularly changing its altsetting via set_alt().  There may
 316  * also be class-specific or vendor-specific requests to handle.
 317  *
 318  * All interface identifier should be allocated using this routine, to
 319  * ensure that for example different functions don't wrongly assign
 320  * different meanings to the same identifier.  Note that since interface
 321  * identifiers are configuration-specific, functions used in more than
 322  * one configuration (or more than once in a given configuration) need
 323  * multiple versions of the relevant descriptors.
 324  *
 325  * Returns the interface ID which was allocated; or -ENODEV if no
 326  * more interface IDs can be allocated.
 327  */
 328 int usb_interface_id(struct usb_configuration *config,
 329                 struct usb_function *function)
 330 {
 331         unsigned id = config->next_interface_id;
 332
 333         if (id < MAX_CONFIG_INTERFACES) {
 334                 config->interface[id] = function;
 335                 config->next_interface_id = id + 1;
 336                 return id;
 337         }
 338         return -ENODEV;
 339 }
 340 EXPORT_SYMBOL_GPL(usb_interface_id);
 341
 342 static u8 encode_bMaxPower(enum usb_device_speed speed,
 343                 struct usb_configuration *c)
 344 {
 345         unsigned val;
 346
 347         if (c->MaxPower)
 348                 val = c->MaxPower;
 349         else
 350                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 351         if (!val)
 352                 return 0;
 353         switch (speed) {
 354         case USB_SPEED_SUPER:
 355                 return DIV_ROUND_UP(val, 8);
 356         default:
 357                 return DIV_ROUND_UP(val, 2);
 358         };
 359 }
 360
 361 static int config_buf(struct usb_configuration *config,
 362                 enum usb_device_speed speed, void *buf, u8 type)
 363 {
 364         struct usb_config_descriptor    *c = buf;
 365         void                            *next = buf + USB_DT_CONFIG_SIZE;
 366         int                             len;
 367         struct usb_function             *f;
 368         int                             status;
 369         int                             interfaceCount = 0;
 370
 371         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 372         /* write the config descriptor */
 373         c = buf;
 374         c->bLength = USB_DT_CONFIG_SIZE;
 375         c->bDescriptorType = type;
 376         /* wTotalLength is written later */
 377         c->bNumInterfaces = config->next_interface_id;
 378         c->bConfigurationValue = config->bConfigurationValue;
 379         c->iConfiguration = config->iConfiguration;
 380         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 381         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
 382                 c->bmAttributes |= USB_CONFIG_ATT_SELFPOWER;
 383         c->bMaxPower = encode_bMaxPower(speed, config);
 384
 385         /* There may be e.g. OTG descriptors */
 386         if (config->descriptors) {
 387                 status = usb_descriptor_fillbuf(next, len,
 388                                 config->descriptors);
 389                 if (status < 0)
 390                         return status;
 391                 len -= status;
 392                 next += status;
 393         }
 394
 395         /* add each function's descriptors */
 396         list_for_each_entry(f, &config->functions, list) {
 397                 struct usb_descriptor_header **descriptors;
 398
 399                 switch (speed) {
 400                 case USB_SPEED_SUPER:
 401                         descriptors = f->ss_descriptors;
 402                         break;
 403                 case USB_SPEED_HIGH:
 404                         descriptors = f->hs_descriptors;
 405                         break;
 406                 default:
 407                         descriptors = f->fs_descriptors;
 408                 }
 409
 410                 if (f->hidden || !descriptors || descriptors[0] == NULL) {
 411                         for (; f != config->interface[interfaceCount];) {
 412                                 interfaceCount++;
 413                                 c->bNumInterfaces--;
 414                         }
 415                         continue;
 416                 }
 417                 for (; f != config->interface[interfaceCount];)
 418                         interfaceCount++;
 419
 420                 status = usb_descriptor_fillbuf(next, len,
 421                         (const struct usb_descriptor_header **) descriptors);
 422                 if (status < 0)
 423                         return status;
 424                 len -= status;
 425                 next += status;
 426         }
 427
 428         len = next - buf;
 429         c->wTotalLength = cpu_to_le16(len);
 430         return len;
 431 }
 432
 433 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 434 {
 435         struct usb_gadget               *gadget = cdev->gadget;
 436         struct usb_configuration        *c;
 437         u8                              type = w_value >> 8;
 438         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 439
 440         if (gadget->speed == USB_SPEED_SUPER)
 441                 speed = gadget->speed;
 442         else if (gadget_is_dualspeed(gadget)) {
 443                 int     hs = 0;
 444                 if (gadget->speed == USB_SPEED_HIGH)
 445                         hs = 1;
 446                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 447                         hs = !hs;
 448                 if (hs)
 449                         speed = USB_SPEED_HIGH;
 450
 451         }
 452
 453         /* This is a lookup by config *INDEX* */
 454         w_value &= 0xff;
 455         list_for_each_entry(c, &cdev->configs, list) {
 456                 /* ignore configs that won't work at this speed */
 457                 switch (speed) {
 458                 case USB_SPEED_SUPER:
 459                         if (!c->superspeed)
 460                                 continue;
 461                         break;
 462                 case USB_SPEED_HIGH:
 463                         if (!c->highspeed)
 464                                 continue;
 465                         break;
 466                 default:
 467                         if (!c->fullspeed)
 468                                 continue;
 469                 }
 470
 471                 if (w_value == 0)
 472                         return config_buf(c, speed, cdev->req->buf, type);
 473                 w_value--;
 474         }
 475         return -EINVAL;
 476 }
 477
 478 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 479 {
 480         struct usb_gadget               *gadget = cdev->gadget;
 481         struct usb_configuration        *c;
 482         unsigned                        count = 0;
 483         int                             hs = 0;
 484         int                             ss = 0;
 485
 486         if (gadget_is_dualspeed(gadget)) {
 487                 if (gadget->speed == USB_SPEED_HIGH)
 488                         hs = 1;
 489                 if (gadget->speed == USB_SPEED_SUPER)
 490                         ss = 1;
 491                 if (type == USB_DT_DEVICE_QUALIFIER)
 492                         hs = !hs;
 493         }
 494         list_for_each_entry(c, &cdev->configs, list) {
 495                 /* ignore configs that won't work at this speed */
 496                 if (ss) {
 497                         if (!c->superspeed)
 498                                 continue;
 499                 } else if (hs) {
 500                         if (!c->highspeed)
 501                                 continue;
 502                 } else {
 503                         if (!c->fullspeed)
 504                                 continue;
 505                 }
 506                 count++;
 507         }
 508         return count;
 509 }
 510
 511 /**
 512  * bos_desc() - prepares the BOS descriptor.
 513  * @cdev: pointer to usb_composite device to generate the bos
 514  *      descriptor for
 515  *
 516  * This function generates the BOS (Binary Device Object)
 517  * descriptor and its device capabilities descriptors. The BOS
 518  * descriptor should be supported by a SuperSpeed device.
 519  */
 520 static int bos_desc(struct usb_composite_dev *cdev)
 521 {
 522         struct usb_ext_cap_descriptor   *usb_ext;
 523         struct usb_ss_cap_descriptor    *ss_cap;
 524         struct usb_dcd_config_params    dcd_config_params;
 525         struct usb_bos_descriptor       *bos = cdev->req->buf;
 526
 527         bos->bLength = USB_DT_BOS_SIZE;
 528         bos->bDescriptorType = USB_DT_BOS;
 529
 530         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 531         bos->bNumDeviceCaps = 0;
 532
 533         /*
 534          * A SuperSpeed device shall include the USB2.0 extension descriptor
 535          * and shall support LPM when operating in USB2.0 HS mode.
 536          */
 537         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 538         bos->bNumDeviceCaps++;
 539         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 540         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 541         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 542         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 543         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
 544
 545         /*
 546          * The Superspeed USB Capability descriptor shall be implemented by all
 547          * SuperSpeed devices.
 548          */
 549         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 550         bos->bNumDeviceCaps++;
 551         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 552         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 553         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 554         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 555         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 556         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 557                                 USB_FULL_SPEED_OPERATION |
 558                                 USB_HIGH_SPEED_OPERATION |
 559                                 USB_5GBPS_OPERATION);
 560         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 561
 562         /* Get Controller configuration */
 563         if (cdev->gadget->ops->get_config_params)
 564                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 565         else {
 566                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 567                 dcd_config_params.bU2DevExitLat =
 568                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 569         }
 570         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 571         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 572
 573         return le16_to_cpu(bos->wTotalLength);
 574 }
 575
 576 static void device_qual(struct usb_composite_dev *cdev)
 577 {
 578         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 579
 580         qual->bLength = sizeof(*qual);
 581         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 582         /* POLICY: same bcdUSB and device type info at both speeds */
 583         qual->bcdUSB = cdev->desc.bcdUSB;
 584         qual->bDeviceClass = cdev->desc.bDeviceClass;
 585         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 586         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 587         /* ASSUME same EP0 fifo size at both speeds */
 588         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 589         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 590         qual->bRESERVED = 0;
 591 }
 592
 593 /*-------------------------------------------------------------------------*/
 594
 595 static void reset_config(struct usb_composite_dev *cdev)
 596 {
 597         struct usb_function             *f;
 598
 599         DBG(cdev, "reset config\n");
 600
 601         list_for_each_entry(f, &cdev->config->functions, list) {
 602                 if (f->disable)
 603                         f->disable(f);
 604
 605                 bitmap_zero(f->endpoints, 32);
 606         }
 607         cdev->config = NULL;
 608         cdev->delayed_status = 0;
 609 }
 610
 611 static int set_config(struct usb_composite_dev *cdev,
 612                 const struct usb_ctrlrequest *ctrl, unsigned number)
 613 {
 614         struct usb_gadget       *gadget = cdev->gadget;
 615         struct usb_configuration *c = NULL;
 616         int                     result = -EINVAL;
 617         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 618         int                     tmp;
 619
 620         if (number) {
 621                 list_for_each_entry(c, &cdev->configs, list) {
 622                         if (c->bConfigurationValue == number) {
 623                                 /*
 624                                  * We disable the FDs of the previous
 625                                  * configuration only if the new configuration
 626                                  * is a valid one
 627                                  */
 628                                 if (cdev->config)
 629                                         reset_config(cdev);
 630                                 result = 0;
 631                                 break;
 632                         }
 633                 }
 634                 if (result < 0)
 635                         goto done;
 636         } else { /* Zero configuration value - need to reset the config */
 637                 if (cdev->config)
 638                         reset_config(cdev);
 639                 result = 0;
 640         }
 641
 642         INFO(cdev, "%s config #%d: %s\n",
 643              usb_speed_string(gadget->speed),
 644              number, c ? c->label : "unconfigured");
 645
 646         if (!c)
 647                 goto done;
 648
 649         cdev->config = c;
 650
 651         /* Initialize all interfaces by setting them to altsetting zero. */
 652         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 653                 struct usb_function     *f = c->interface[tmp];
 654                 struct usb_descriptor_header **descriptors;
 655
 656                 if (!f)
 657                         break;
 658
 659                 /*
 660                  * Record which endpoints are used by the function. This is used
 661                  * to dispatch control requests targeted at that endpoint to the
 662                  * function's setup callback instead of the current
 663                  * configuration's setup callback.
 664                  */
 665                 switch (gadget->speed) {
 666                 case USB_SPEED_SUPER:
 667                         descriptors = f->ss_descriptors;
 668                         break;
 669                 case USB_SPEED_HIGH:
 670                         descriptors = f->hs_descriptors;
 671                         break;
 672                 default:
 673                         descriptors = f->fs_descriptors;
 674                 }
 675
 676                 for (; *descriptors; ++descriptors) {
 677                         struct usb_endpoint_descriptor *ep;
 678                         int addr;
 679
 680                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 681                                 continue;
 682
 683                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 684                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 685                              |  (ep->bEndpointAddress & 0x0f);
 686                         set_bit(addr, f->endpoints);
 687                 }
 688
 689                 result = f->set_alt(f, tmp, 0);
 690                 if (result < 0) {
 691                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 692                                         tmp, f->name, f, result);
 693
 694                         reset_config(cdev);
 695                         goto done;
 696                 }
 697
 698                 if (result == USB_GADGET_DELAYED_STATUS) {
 699                         DBG(cdev,
 700                          "%s: interface %d (%s) requested delayed status\n",
 701                                         __func__, tmp, f->name);
 702                         cdev->delayed_status++;
 703                         DBG(cdev, "delayed_status count %d\n",
 704                                         cdev->delayed_status);
 705                 }
 706         }
 707
 708         /* when we return, be sure our power usage is valid */
 709         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 710 done:
 711         usb_gadget_vbus_draw(gadget, power);
 712         if (result >= 0 && cdev->delayed_status)
 713                 result = USB_GADGET_DELAYED_STATUS;
 714         return result;
 715 }
 716
 717 int usb_add_config_only(struct usb_composite_dev *cdev,
 718                 struct usb_configuration *config)
 719 {
 720         struct usb_configuration *c;
 721
 722         if (!config->bConfigurationValue)
 723                 return -EINVAL;
 724
 725         /* Prevent duplicate configuration identifiers */
 726         list_for_each_entry(c, &cdev->configs, list) {
 727                 if (c->bConfigurationValue == config->bConfigurationValue)
 728                         return -EBUSY;
 729         }
 730
 731         config->cdev = cdev;
 732         list_add_tail(&config->list, &cdev->configs);
 733
 734         INIT_LIST_HEAD(&config->functions);
 735         config->next_interface_id = 0;
 736         memset(config->interface, 0, sizeof(config->interface));
 737
 738         return 0;
 739 }
 740 EXPORT_SYMBOL_GPL(usb_add_config_only);
 741
 742 /**
 743  * usb_add_config() - add a configuration to a device.
 744  * @cdev: wraps the USB gadget
 745  * @config: the configuration, with bConfigurationValue assigned
 746  * @bind: the configuration's bind function
 747  * Context: single threaded during gadget setup
 748  *
 749  * One of the main tasks of a composite @bind() routine is to
 750  * add each of the configurations it supports, using this routine.
 751  *
 752  * This function returns the value of the configuration's @bind(), which
 753  * is zero for success else a negative errno value.  Binding configurations
 754  * assigns global resources including string IDs, and per-configuration
 755  * resources such as interface IDs and endpoints.
 756  */
 757 int usb_add_config(struct usb_composite_dev *cdev,
 758                 struct usb_configuration *config,
 759                 int (*bind)(struct usb_configuration *))
 760 {
 761         int                             status = -EINVAL;
 762
 763         if (!bind)
 764                 goto done;
 765
 766         DBG(cdev, "adding config #%u '%s'/%p\n",
 767                         config->bConfigurationValue,
 768                         config->label, config);
 769
 770         status = usb_add_config_only(cdev, config);
 771         if (status)
 772                 goto done;
 773
 774         status = bind(config);
 775         if (status < 0) {
 776                 while (!list_empty(&config->functions)) {
 777                         struct usb_function             *f;
 778
 779                         f = list_first_entry(&config->functions,
 780                                         struct usb_function, list);
 781                         list_del(&f->list);
 782                         if (f->unbind) {
 783                                 DBG(cdev, "unbind function '%s'/%p\n",
 784                                         f->name, f);
 785                                 f->unbind(config, f);
 786                                 /* may free memory for "f" */
 787                         }
 788                 }
 789                 list_del(&config->list);
 790                 config->cdev = NULL;
 791         } else {
 792                 unsigned        i;
 793
 794                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 795                         config->bConfigurationValue, config,
 796                         config->superspeed ? " super" : "",
 797                         config->highspeed ? " high" : "",
 798                         config->fullspeed
 799                                 ? (gadget_is_dualspeed(cdev->gadget)
 800                                         ? " full"
 801                                         : " full/low")
 802                                 : "");
 803
 804                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 805                         struct usb_function     *f = config->interface[i];
 806
 807                         if (!f)
 808                                 continue;
 809                         DBG(cdev, "  interface %d = %s/%p\n",
 810                                 i, f->name, f);
 811                 }
 812         }
 813
 814         /* set_alt(), or next bind(), sets up
 815          * ep->driver_data as needed.
 816          */
 817         usb_ep_autoconfig_reset(cdev->gadget);
 818
 819 done:
 820         if (status)
 821                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 822                                 config->bConfigurationValue, status);
 823         return status;
 824 }
 825 EXPORT_SYMBOL_GPL(usb_add_config);
 826
 827 static void unbind_config(struct usb_composite_dev *cdev,
 828                               struct usb_configuration *config)
 829 {
 830         while (!list_empty(&config->functions)) {
 831                 struct usb_function             *f;
 832
 833                 f = list_first_entry(&config->functions,
 834                                 struct usb_function, list);
 835                 list_del(&f->list);
 836                 if (f->unbind) {
 837                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 838                         f->unbind(config, f);
 839                         /* may free memory for "f" */
 840                 }
 841         }
 842         if (config->unbind) {
 843                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 844                 config->unbind(config);
 845                         /* may free memory for "c" */
 846         }
 847 }
 848
 849 /**
 850  * usb_remove_config() - remove a configuration from a device.
 851  * @cdev: wraps the USB gadget
 852  * @config: the configuration
 853  *
 854  * Drivers must call usb_gadget_disconnect before calling this function
 855  * to disconnect the device from the host and make sure the host will not
 856  * try to enumerate the device while we are changing the config list.
 857  */
 858 void usb_remove_config(struct usb_composite_dev *cdev,
 859                       struct usb_configuration *config)
 860 {
 861         unsigned long flags;
 862
 863         spin_lock_irqsave(&cdev->lock, flags);
 864
 865         if (cdev->config == config)
 866                 reset_config(cdev);
 867
 868         list_del(&config->list);
 869
 870         spin_unlock_irqrestore(&cdev->lock, flags);
 871
 872         unbind_config(cdev, config);
 873 }
 874
 875 /*-------------------------------------------------------------------------*/
 876
 877 /* We support strings in multiple languages ... string descriptor zero
 878  * says which languages are supported.  The typical case will be that
 879  * only one language (probably English) is used, with I18N handled on
 880  * the host side.
 881  */
 882
 883 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 884 {
 885         const struct usb_gadget_strings *s;
 886         __le16                          language;
 887         __le16                          *tmp;
 888
 889         while (*sp) {
 890                 s = *sp;
 891                 language = cpu_to_le16(s->language);
 892                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 893                         if (*tmp == language)
 894                                 goto repeat;
 895                 }
 896                 *tmp++ = language;
 897 repeat:
 898                 sp++;
 899         }
 900 }
 901
 902 static int lookup_string(
 903         struct usb_gadget_strings       **sp,
 904         void                            *buf,
 905         u16                             language,
 906         int                             id
 907 )
 908 {
 909         struct usb_gadget_strings       *s;
 910         int                             value;
 911
 912         while (*sp) {
 913                 s = *sp++;
 914                 if (s->language != language)
 915                         continue;
 916                 value = usb_gadget_get_string(s, id, buf);
 917                 if (value > 0)
 918                         return value;
 919         }
 920         return -EINVAL;
 921 }
 922
 923 static int get_string(struct usb_composite_dev *cdev,
 924                 void *buf, u16 language, int id)
 925 {
 926         struct usb_composite_driver     *composite = cdev->driver;
 927         struct usb_gadget_string_container *uc;
 928         struct usb_configuration        *c;
 929         struct usb_function             *f;
 930         int                             len;
 931
 932         /* Yes, not only is USB's I18N support probably more than most
 933          * folk will ever care about ... also, it's all supported here.
 934          * (Except for UTF8 support for Unicode's "Astral Planes".)
 935          */
 936
 937         /* 0 == report all available language codes */
 938         if (id == 0) {
 939                 struct usb_string_descriptor    *s = buf;
 940                 struct usb_gadget_strings       **sp;
 941
 942                 memset(s, 0, 256);
 943                 s->bDescriptorType = USB_DT_STRING;
 944
 945                 sp = composite->strings;
 946                 if (sp)
 947                         collect_langs(sp, s->wData);
 948
 949                 list_for_each_entry(c, &cdev->configs, list) {
 950                         sp = c->strings;
 951                         if (sp)
 952                                 collect_langs(sp, s->wData);
 953
 954                         list_for_each_entry(f, &c->functions, list) {
 955                                 sp = f->strings;
 956                                 if (sp)
 957                                         collect_langs(sp, s->wData);
 958                         }
 959                 }
 960                 list_for_each_entry(uc, &cdev->gstrings, list) {
 961                         struct usb_gadget_strings **sp;
 962
 963                         sp = get_containers_gs(uc);
 964                         collect_langs(sp, s->wData);
 965                 }
 966
 967                 for (len = 0; len <= 126 && s->wData[len]; len++)
 968                         continue;
 969                 if (!len)
 970                         return -EINVAL;
 971
 972                 s->bLength = 2 * (len + 1);
 973                 return s->bLength;
 974         }
 975
 976         list_for_each_entry(uc, &cdev->gstrings, list) {
 977                 struct usb_gadget_strings **sp;
 978
 979                 sp = get_containers_gs(uc);
 980                 len = lookup_string(sp, buf, language, id);
 981                 if (len > 0)
 982                         return len;
 983         }
 984
 985         /* String IDs are device-scoped, so we look up each string
 986          * table we're told about.  These lookups are infrequent;
 987          * simpler-is-better here.
 988          */
 989         if (composite->strings) {
 990                 len = lookup_string(composite->strings, buf, language, id);
 991                 if (len > 0)
 992                         return len;
 993         }
 994         list_for_each_entry(c, &cdev->configs, list) {
 995                 if (c->strings) {
 996                         len = lookup_string(c->strings, buf, language, id);
 997                         if (len > 0)
 998                                 return len;
 999                 }
1000                 list_for_each_entry(f, &c->functions, list) {
1001                         if (!f->strings)
1002                                 continue;
1003                         len = lookup_string(f->strings, buf, language, id);
1004                         if (len > 0)
1005                                 return len;
1006                 }
1007         }
1008         return -EINVAL;
1009 }
1010
1011 /**
1012  * usb_string_id() - allocate an unused string ID
1013  * @cdev: the device whose string descriptor IDs are being allocated
1014  * Context: single threaded during gadget setup
1015  *
1016  * @usb_string_id() is called from bind() callbacks to allocate
1017  * string IDs.  Drivers for functions, configurations, or gadgets will
1018  * then store that ID in the appropriate descriptors and string table.
1019  *
1020  * All string identifier should be allocated using this,
1021  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1022  * that for example different functions don't wrongly assign different
1023  * meanings to the same identifier.
1024  */
1025 int usb_string_id(struct usb_composite_dev *cdev)
1026 {
1027         if (cdev->next_string_id < 254) {
1028                 /* string id 0 is reserved by USB spec for list of
1029                  * supported languages */
1030                 /* 255 reserved as well? -- mina86 */
1031                 cdev->next_string_id++;
1032                 return cdev->next_string_id;
1033         }
1034         return -ENODEV;
1035 }
1036 EXPORT_SYMBOL_GPL(usb_string_id);
1037
1038 /**
1039  * usb_string_ids() - allocate unused string IDs in batch
1040  * @cdev: the device whose string descriptor IDs are being allocated
1041  * @str: an array of usb_string objects to assign numbers to
1042  * Context: single threaded during gadget setup
1043  *
1044  * @usb_string_ids() is called from bind() callbacks to allocate
1045  * string IDs.  Drivers for functions, configurations, or gadgets will
1046  * then copy IDs from the string table to the appropriate descriptors
1047  * and string table for other languages.
1048  *
1049  * All string identifier should be allocated using this,
1050  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1051  * example different functions don't wrongly assign different meanings
1052  * to the same identifier.
1053  */
1054 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1055 {
1056         int next = cdev->next_string_id;
1057
1058         for (; str->s; ++str) {
1059                 if (unlikely(next >= 254))
1060                         return -ENODEV;
1061                 str->id = ++next;
1062         }
1063
1064         cdev->next_string_id = next;
1065
1066         return 0;
1067 }
1068 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1069
1070 static struct usb_gadget_string_container *copy_gadget_strings(
1071                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1072                 unsigned n_strings)
1073 {
1074         struct usb_gadget_string_container *uc;
1075         struct usb_gadget_strings **gs_array;
1076         struct usb_gadget_strings *gs;
1077         struct usb_string *s;
1078         unsigned mem;
1079         unsigned n_gs;
1080         unsigned n_s;
1081         void *stash;
1082
1083         mem = sizeof(*uc);
1084         mem += sizeof(void *) * (n_gstrings + 1);
1085         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1086         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1087         uc = kmalloc(mem, GFP_KERNEL);
1088         if (!uc)
1089                 return ERR_PTR(-ENOMEM);
1090         gs_array = get_containers_gs(uc);
1091         stash = uc->stash;
1092         stash += sizeof(void *) * (n_gstrings + 1);
1093         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1094                 struct usb_string *org_s;
1095
1096                 gs_array[n_gs] = stash;
1097                 gs = gs_array[n_gs];
1098                 stash += sizeof(struct usb_gadget_strings);
1099                 gs->language = sp[n_gs]->language;
1100                 gs->strings = stash;
1101                 org_s = sp[n_gs]->strings;
1102
1103                 for (n_s = 0; n_s < n_strings; n_s++) {
1104                         s = stash;
1105                         stash += sizeof(struct usb_string);
1106                         if (org_s->s)
1107                                 s->s = org_s->s;
1108                         else
1109                                 s->s = "";
1110                         org_s++;
1111                 }
1112                 s = stash;
1113                 s->s = NULL;
1114                 stash += sizeof(struct usb_string);
1115
1116         }
1117         gs_array[n_gs] = NULL;
1118         return uc;
1119 }
1120
1121 /**
1122  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1123  * @cdev: the device whose string descriptor IDs are being allocated
1124  * and attached.
1125  * @sp: an array of usb_gadget_strings to attach.
1126  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1127  *
1128  * This function will create a deep copy of usb_gadget_strings and usb_string
1129  * and attach it to the cdev. The actual string (usb_string.s) will not be
1130  * copied but only a referenced will be made. The struct usb_gadget_strings
1131  * array may contain multiple languges and should be NULL terminated.
1132  * The ->language pointer of each struct usb_gadget_strings has to contain the
1133  * same amount of entries.
1134  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1135  * usb_string entry of es-ES containts the translation of the first usb_string
1136  * entry of en-US. Therefore both entries become the same id assign.
1137  */
1138 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1139                 struct usb_gadget_strings **sp, unsigned n_strings)
1140 {
1141         struct usb_gadget_string_container *uc;
1142         struct usb_gadget_strings **n_gs;
1143         unsigned n_gstrings = 0;
1144         unsigned i;
1145         int ret;
1146
1147         for (i = 0; sp[i]; i++)
1148                 n_gstrings++;
1149
1150         if (!n_gstrings)
1151                 return ERR_PTR(-EINVAL);
1152
1153         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1154         if (IS_ERR(uc))
1155                 return ERR_PTR(PTR_ERR(uc));
1156
1157         n_gs = get_containers_gs(uc);
1158         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1159         if (ret)
1160                 goto err;
1161
1162         for (i = 1; i < n_gstrings; i++) {
1163                 struct usb_string *m_s;
1164                 struct usb_string *s;
1165                 unsigned n;
1166
1167                 m_s = n_gs[0]->strings;
1168                 s = n_gs[i]->strings;
1169                 for (n = 0; n < n_strings; n++) {
1170                         s->id = m_s->id;
1171                         s++;
1172                         m_s++;
1173                 }
1174         }
1175         list_add_tail(&uc->list, &cdev->gstrings);
1176         return n_gs[0]->strings;
1177 err:
1178         kfree(uc);
1179         return ERR_PTR(ret);
1180 }
1181 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1182
1183 /**
1184  * usb_string_ids_n() - allocate unused string IDs in batch
1185  * @c: the device whose string descriptor IDs are being allocated
1186  * @n: number of string IDs to allocate
1187  * Context: single threaded during gadget setup
1188  *
1189  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1190  * valid IDs.  At least provided that @n is non-zero because if it
1191  * is, returns last requested ID which is now very useful information.
1192  *
1193  * @usb_string_ids_n() is called from bind() callbacks to allocate
1194  * string IDs.  Drivers for functions, configurations, or gadgets will
1195  * then store that ID in the appropriate descriptors and string table.
1196  *
1197  * All string identifier should be allocated using this,
1198  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1199  * example different functions don't wrongly assign different meanings
1200  * to the same identifier.
1201  */
1202 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1203 {
1204         unsigned next = c->next_string_id;
1205         if (unlikely(n > 254 || (unsigned)next + n > 254))
1206                 return -ENODEV;
1207         c->next_string_id += n;
1208         return next + 1;
1209 }
1210 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1211
1212 /*-------------------------------------------------------------------------*/
1213
1214 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1215 {
1216         if (req->status || req->actual != req->length)
1217                 DBG((struct usb_composite_dev *) ep->driver_data,
1218                                 "setup complete --> %d, %d/%d\n",
1219                                 req->status, req->actual, req->length);
1220 }
1221
1222 /*
1223  * The setup() callback implements all the ep0 functionality that's
1224  * not handled lower down, in hardware or the hardware driver(like
1225  * device and endpoint feature flags, and their status).  It's all
1226  * housekeeping for the gadget function we're implementing.  Most of
1227  * the work is in config and function specific setup.
1228  */
1229 int
1230 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1231 {
1232         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1233         struct usb_request              *req = cdev->req;
1234         int                             value = -EOPNOTSUPP;
1235         int                             status = 0;
1236         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1237         u8                              intf = w_index & 0xFF;
1238         u16                             w_value = le16_to_cpu(ctrl->wValue);
1239         u16                             w_length = le16_to_cpu(ctrl->wLength);
1240         struct usb_function             *f = NULL;
1241         u8                              endp;
1242
1243         /* partial re-init of the response message; the function or the
1244          * gadget might need to intercept e.g. a control-OUT completion
1245          * when we delegate to it.
1246          */
1247         req->zero = 0;
1248         req->complete = composite_setup_complete;
1249         req->length = 0;
1250         gadget->ep0->driver_data = cdev;
1251
1252         switch (ctrl->bRequest) {
1253
1254         /* we handle all standard USB descriptors */
1255         case USB_REQ_GET_DESCRIPTOR:
1256                 if (ctrl->bRequestType != USB_DIR_IN)
1257                         goto unknown;
1258                 switch (w_value >> 8) {
1259
1260                 case USB_DT_DEVICE:
1261                         cdev->desc.bNumConfigurations =
1262                                 count_configs(cdev, USB_DT_DEVICE);
1263                         cdev->desc.bMaxPacketSize0 =
1264                                 cdev->gadget->ep0->maxpacket;
1265                         if (gadget_is_superspeed(gadget)) {
1266                                 if (gadget->speed >= USB_SPEED_SUPER) {
1267                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1268                                         cdev->desc.bMaxPacketSize0 = 9;
1269                                 } else {
1270                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1271                                 }
1272                         }
1273
1274                         value = min(w_length, (u16) sizeof cdev->desc);
1275                         memcpy(req->buf, &cdev->desc, value);
1276                         break;
1277                 case USB_DT_DEVICE_QUALIFIER:
1278                         if (!gadget_is_dualspeed(gadget) ||
1279                             gadget->speed >= USB_SPEED_SUPER)
1280                                 break;
1281                         device_qual(cdev);
1282                         value = min_t(int, w_length,
1283                                 sizeof(struct usb_qualifier_descriptor));
1284                         break;
1285                 case USB_DT_OTHER_SPEED_CONFIG:
1286                         if (!gadget_is_dualspeed(gadget) ||
1287                             gadget->speed >= USB_SPEED_SUPER)
1288                                 break;
1289                         /* FALLTHROUGH */
1290                 case USB_DT_CONFIG:
1291                         value = config_desc(cdev, w_value);
1292                         if (value >= 0)
1293                                 value = min(w_length, (u16) value);
1294                         break;
1295                 case USB_DT_STRING:
1296                         value = get_string(cdev, req->buf,
1297                                         w_index, w_value & 0xff);
1298                         if (value >= 0)
1299                                 value = min(w_length, (u16) value);
1300                         break;
1301                 case USB_DT_BOS:
1302                         if (gadget_is_superspeed(gadget)) {
1303                                 value = bos_desc(cdev);
1304                                 value = min(w_length, (u16) value);
1305                         }
1306                         break;
1307                 }
1308                 break;
1309
1310         /* any number of configs can work */
1311         case USB_REQ_SET_CONFIGURATION:
1312                 if (ctrl->bRequestType != 0)
1313                         goto unknown;
1314                 if (gadget_is_otg(gadget)) {
1315                         if (gadget->a_hnp_support)
1316                                 DBG(cdev, "HNP available\n");
1317                         else if (gadget->a_alt_hnp_support)
1318                                 DBG(cdev, "HNP on another port\n");
1319                         else
1320                                 VDBG(cdev, "HNP inactive\n");
1321                 }
1322                 spin_lock(&cdev->lock);
1323                 value = set_config(cdev, ctrl, w_value);
1324                 spin_unlock(&cdev->lock);
1325                 break;
1326         case USB_REQ_GET_CONFIGURATION:
1327                 if (ctrl->bRequestType != USB_DIR_IN)
1328                         goto unknown;
1329                 if (cdev->config)
1330                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1331                 else
1332                         *(u8 *)req->buf = 0;
1333                 value = min(w_length, (u16) 1);
1334                 break;
1335
1336         /* function drivers must handle get/set altsetting; if there's
1337          * no get() method, we know only altsetting zero works.
1338          */
1339         case USB_REQ_SET_INTERFACE:
1340                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1341                         goto unknown;
1342                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1343                         break;
1344                 f = cdev->config->interface[intf];
1345                 if (!f)
1346                         break;
1347                 if (w_value && !f->set_alt)
1348                         break;
1349                 value = f->set_alt(f, w_index, w_value);
1350                 if (value == USB_GADGET_DELAYED_STATUS) {
1351                         DBG(cdev,
1352                          "%s: interface %d (%s) requested delayed status\n",
1353                                         __func__, intf, f->name);
1354                         cdev->delayed_status++;
1355                         DBG(cdev, "delayed_status count %d\n",
1356                                         cdev->delayed_status);
1357                 }
1358                 break;
1359         case USB_REQ_GET_INTERFACE:
1360                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1361                         goto unknown;
1362                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1363                         break;
1364                 f = cdev->config->interface[intf];
1365                 if (!f)
1366                         break;
1367                 /* lots of interfaces only need altsetting zero... */
1368                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1369                 if (value < 0)
1370                         break;
1371                 *((u8 *)req->buf) = value;
1372                 value = min(w_length, (u16) 1);
1373                 break;
1374
1375         /*
1376          * USB 3.0 additions:
1377          * Function driver should handle get_status request. If such cb
1378          * wasn't supplied we respond with default value = 0
1379          * Note: function driver should supply such cb only for the first
1380          * interface of the function
1381          */
1382         case USB_REQ_GET_STATUS:
1383                 if (!gadget_is_superspeed(gadget))
1384                         goto unknown;
1385                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1386                         goto unknown;
1387                 value = 2;      /* This is the length of the get_status reply */
1388                 put_unaligned_le16(0, req->buf);
1389                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1390                         break;
1391                 f = cdev->config->interface[intf];
1392                 if (!f)
1393                         break;
1394                 status = f->get_status ? f->get_status(f) : 0;
1395                 if (status < 0)
1396                         break;
1397                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1398                 break;
1399         /*
1400          * Function drivers should handle SetFeature/ClearFeature
1401          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1402          * only for the first interface of the function
1403          */
1404         case USB_REQ_CLEAR_FEATURE:
1405         case USB_REQ_SET_FEATURE:
1406                 if (!gadget_is_superspeed(gadget))
1407                         goto unknown;
1408                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1409                         goto unknown;
1410                 switch (w_value) {
1411                 case USB_INTRF_FUNC_SUSPEND:
1412                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1413                                 break;
1414                         f = cdev->config->interface[intf];
1415                         if (!f)
1416                                 break;
1417                         value = 0;
1418                         if (f->func_suspend)
1419                                 value = f->func_suspend(f, w_index >> 8);
1420                         if (value < 0) {
1421                                 ERROR(cdev,
1422                                       "func_suspend() returned error %d\n",
1423                                       value);
1424                                 value = 0;
1425                         }
1426                         break;
1427                 }
1428                 break;
1429         default:
1430 unknown:
1431                 VDBG(cdev,
1432                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1433                         ctrl->bRequestType, ctrl->bRequest,
1434                         w_value, w_index, w_length);
1435
1436                 /* functions always handle their interfaces and endpoints...
1437                  * punt other recipients (other, WUSB, ...) to the current
1438                  * configuration code.
1439                  *
1440                  * REVISIT it could make sense to let the composite device
1441                  * take such requests too, if that's ever needed:  to work
1442                  * in config 0, etc.
1443                  */
1444                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1445                 case USB_RECIP_INTERFACE:
1446                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1447                                 break;
1448                         f = cdev->config->interface[intf];
1449                         break;
1450
1451                 case USB_RECIP_ENDPOINT:
1452                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1453                         list_for_each_entry(f, &cdev->config->functions, list) {
1454                                 if (test_bit(endp, f->endpoints))
1455                                         break;
1456                         }
1457                         if (&f->list == &cdev->config->functions)
1458                                 f = NULL;
1459                         break;
1460                 }
1461
1462                 if (f && f->setup)
1463                         value = f->setup(f, ctrl);
1464                 else {
1465                         struct usb_configuration        *c;
1466
1467                         c = cdev->config;
1468                         if (c && c->setup)
1469                                 value = c->setup(c, ctrl);
1470                 }
1471
1472                 /* If the vendor request is not processed (value < 0),
1473                  * call all device registered configure setup callbacks
1474                  * to process it.
1475                  * This is used to handle the following cases:
1476                  * - vendor request is for the device and arrives before
1477                  * setconfiguration.
1478                  * - Some devices are required to handle vendor request before
1479                  * setconfiguration such as MTP, USBNET.
1480                  */
1481
1482                 if (value < 0) {
1483                         struct usb_configuration        *cfg;
1484
1485                         list_for_each_entry(cfg, &cdev->configs, list) {
1486                         if (cfg && cfg->setup)
1487                                 value = cfg->setup(cfg, ctrl);
1488                         }
1489                 }
1490
1491                 goto done;
1492         }
1493
1494         /* respond with data transfer before status phase? */
1495         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1496                 req->length = value;
1497                 req->zero = value < w_length;
1498                 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1499                 if (value < 0) {
1500                         DBG(cdev, "ep_queue --> %d\n", value);
1501                         req->status = 0;
1502                         composite_setup_complete(gadget->ep0, req);
1503                 }
1504         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1505                 WARN(cdev,
1506                         "%s: Delayed status not supported for w_length != 0",
1507                         __func__);
1508         }
1509
1510 done:
1511         /* device either stalls (value < 0) or reports success */
1512         return value;
1513 }
1514
1515 void composite_disconnect(struct usb_gadget *gadget)
1516 {
1517         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1518         unsigned long                   flags;
1519
1520         /* REVISIT:  should we have config and device level
1521          * disconnect callbacks?
1522          */
1523         if (!cdev)
1524                 return;
1525
1526         spin_lock_irqsave(&cdev->lock, flags);
1527         if (cdev->config)
1528                 reset_config(cdev);
1529         if (cdev->driver->disconnect)
1530                 cdev->driver->disconnect(cdev);
1531         spin_unlock_irqrestore(&cdev->lock, flags);
1532 }
1533
1534 /*-------------------------------------------------------------------------*/
1535
1536 static ssize_t composite_show_suspended(struct device *dev,
1537                                         struct device_attribute *attr,
1538                                         char *buf)
1539 {
1540         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1541         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1542
1543         return sprintf(buf, "%d\n", cdev->suspended);
1544 }
1545
1546 static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
1547
1548 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1549 {
1550         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1551
1552         /* composite_disconnect() must already have been called
1553          * by the underlying peripheral controller driver!
1554          * so there's no i/o concurrency that could affect the
1555          * state protected by cdev->lock.
1556          */
1557         WARN_ON(cdev->config);
1558
1559         while (!list_empty(&cdev->configs)) {
1560                 struct usb_configuration        *c;
1561                 c = list_first_entry(&cdev->configs,
1562                                 struct usb_configuration, list);
1563                 list_del(&c->list);
1564                 unbind_config(cdev, c);
1565         }
1566         if (cdev->driver->unbind && unbind_driver)
1567                 cdev->driver->unbind(cdev);
1568
1569         composite_dev_cleanup(cdev);
1570
1571         kfree(cdev->def_manufacturer);
1572         kfree(cdev);
1573         set_gadget_data(gadget, NULL);
1574 }
1575
1576 static void composite_unbind(struct usb_gadget *gadget)
1577 {
1578         __composite_unbind(gadget, true);
1579 }
1580
1581 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1582                 const struct usb_device_descriptor *old)
1583 {
1584         __le16 idVendor;
1585         __le16 idProduct;
1586         __le16 bcdDevice;
1587         u8 iSerialNumber;
1588         u8 iManufacturer;
1589         u8 iProduct;
1590
1591         /*
1592          * these variables may have been set in
1593          * usb_composite_overwrite_options()
1594          */
1595         idVendor = new->idVendor;
1596         idProduct = new->idProduct;
1597         bcdDevice = new->bcdDevice;
1598         iSerialNumber = new->iSerialNumber;
1599         iManufacturer = new->iManufacturer;
1600         iProduct = new->iProduct;
1601
1602         *new = *old;
1603         if (idVendor)
1604                 new->idVendor = idVendor;
1605         if (idProduct)
1606                 new->idProduct = idProduct;
1607         if (bcdDevice)
1608                 new->bcdDevice = bcdDevice;
1609         else
1610                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1611         if (iSerialNumber)
1612                 new->iSerialNumber = iSerialNumber;
1613         if (iManufacturer)
1614                 new->iManufacturer = iManufacturer;
1615         if (iProduct)
1616                 new->iProduct = iProduct;
1617 }
1618
1619 int composite_dev_prepare(struct usb_composite_driver *composite,
1620                 struct usb_composite_dev *cdev)
1621 {
1622         struct usb_gadget *gadget = cdev->gadget;
1623         int ret = -ENOMEM;
1624
1625         /* preallocate control response and buffer */
1626         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1627         if (!cdev->req)
1628                 return -ENOMEM;
1629
1630         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
1631         if (!cdev->req->buf)
1632                 goto fail;
1633
1634         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
1635         if (ret)
1636                 goto fail_dev;
1637
1638         cdev->req->complete = composite_setup_complete;
1639         gadget->ep0->driver_data = cdev;
1640
1641         cdev->driver = composite;
1642
1643         /*
1644          * As per USB compliance update, a device that is actively drawing
1645          * more than 100mA from USB must report itself as bus-powered in
1646          * the GetStatus(DEVICE) call.
1647          */
1648         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1649                 usb_gadget_set_selfpowered(gadget);
1650
1651         /* interface and string IDs start at zero via kzalloc.
1652          * we force endpoints to start unassigned; few controller
1653          * drivers will zero ep->driver_data.
1654          */
1655         usb_ep_autoconfig_reset(gadget);
1656         return 0;
1657 fail_dev:
1658         kfree(cdev->req->buf);
1659 fail:
1660         usb_ep_free_request(gadget->ep0, cdev->req);
1661         cdev->req = NULL;
1662         return ret;
1663 }
1664
1665 void composite_dev_cleanup(struct usb_composite_dev *cdev)
1666 {
1667         struct usb_gadget_string_container *uc, *tmp;
1668
1669         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
1670                 list_del(&uc->list);
1671                 kfree(uc);
1672         }
1673         if (cdev->req) {
1674                 kfree(cdev->req->buf);
1675                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
1676         }
1677         cdev->next_string_id = 0;
1678         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
1679 }
1680
1681 static int composite_bind(struct usb_gadget *gadget,
1682                 struct usb_gadget_driver *gdriver)
1683 {
1684         struct usb_composite_dev        *cdev;
1685         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1686         int                             status = -ENOMEM;
1687
1688         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1689         if (!cdev)
1690                 return status;
1691
1692         spin_lock_init(&cdev->lock);
1693         cdev->gadget = gadget;
1694         set_gadget_data(gadget, cdev);
1695         INIT_LIST_HEAD(&cdev->configs);
1696         INIT_LIST_HEAD(&cdev->gstrings);
1697
1698         status = composite_dev_prepare(composite, cdev);
1699         if (status)
1700                 goto fail;
1701
1702         /* composite gadget needs to assign strings for whole device (like
1703          * serial number), register function drivers, potentially update
1704          * power state and consumption, etc
1705          */
1706         status = composite->bind(cdev);
1707         if (status < 0)
1708                 goto fail;
1709
1710         update_unchanged_dev_desc(&cdev->desc, composite->dev);
1711
1712         /* has userspace failed to provide a serial number? */
1713         if (composite->needs_serial && !cdev->desc.iSerialNumber)
1714                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1715
1716         INFO(cdev, "%s ready\n", composite->name);
1717         return 0;
1718
1719 fail:
1720         __composite_unbind(gadget, false);
1721         return status;
1722 }
1723
1724 /*-------------------------------------------------------------------------*/
1725
1726 static void
1727 composite_suspend(struct usb_gadget *gadget)
1728 {
1729         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1730         struct usb_function             *f;
1731
1732         /* REVISIT:  should we have config level
1733          * suspend/resume callbacks?
1734          */
1735         DBG(cdev, "suspend\n");
1736         if (cdev->config) {
1737                 list_for_each_entry(f, &cdev->config->functions, list) {
1738                         if (f->suspend)
1739                                 f->suspend(f);
1740                 }
1741         }
1742         if (cdev->driver->suspend)
1743                 cdev->driver->suspend(cdev);
1744
1745         cdev->suspended = 1;
1746
1747         usb_gadget_vbus_draw(gadget, 2);
1748 }
1749
1750 static void
1751 composite_resume(struct usb_gadget *gadget)
1752 {
1753         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1754         struct usb_function             *f;
1755         u8                              maxpower;
1756
1757         /* REVISIT:  should we have config level
1758          * suspend/resume callbacks?
1759          */
1760         DBG(cdev, "resume\n");
1761         if (cdev->driver->resume)
1762                 cdev->driver->resume(cdev);
1763         if (cdev->config) {
1764                 list_for_each_entry(f, &cdev->config->functions, list) {
1765                         if (f->resume)
1766                                 f->resume(f);
1767                 }
1768
1769                 maxpower = cdev->config->MaxPower;
1770
1771                 usb_gadget_vbus_draw(gadget, maxpower ?
1772                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
1773         }
1774
1775         cdev->suspended = 0;
1776 }
1777
1778 /*-------------------------------------------------------------------------*/
1779
1780 static const struct usb_gadget_driver composite_driver_template = {
1781         .bind           = composite_bind,
1782         .unbind         = composite_unbind,
1783
1784         .setup          = composite_setup,
1785         .disconnect     = composite_disconnect,
1786
1787         .suspend        = composite_suspend,
1788         .resume         = composite_resume,
1789
1790         .driver = {
1791                 .owner          = THIS_MODULE,
1792         },
1793 };
1794
1795 /**
1796  * usb_composite_probe() - register a composite driver
1797  * @driver: the driver to register
1798  *
1799  * Context: single threaded during gadget setup
1800  *
1801  * This function is used to register drivers using the composite driver
1802  * framework.  The return value is zero, or a negative errno value.
1803  * Those values normally come from the driver's @bind method, which does
1804  * all the work of setting up the driver to match the hardware.
1805  *
1806  * On successful return, the gadget is ready to respond to requests from
1807  * the host, unless one of its components invokes usb_gadget_disconnect()
1808  * while it was binding.  That would usually be done in order to wait for
1809  * some userspace participation.
1810  */
1811 int usb_composite_probe(struct usb_composite_driver *driver)
1812 {
1813         struct usb_gadget_driver *gadget_driver;
1814
1815         if (!driver || !driver->dev || !driver->bind)
1816                 return -EINVAL;
1817
1818         if (!driver->name)
1819                 driver->name = "composite";
1820
1821         driver->gadget_driver = composite_driver_template;
1822         gadget_driver = &driver->gadget_driver;
1823
1824         gadget_driver->function =  (char *) driver->name;
1825         gadget_driver->driver.name = driver->name;
1826         gadget_driver->max_speed = driver->max_speed;
1827
1828         return usb_gadget_probe_driver(gadget_driver);
1829 }
1830 EXPORT_SYMBOL_GPL(usb_composite_probe);
1831
1832 /**
1833  * usb_composite_unregister() - unregister a composite driver
1834  * @driver: the driver to unregister
1835  *
1836  * This function is used to unregister drivers using the composite
1837  * driver framework.
1838  */
1839 void usb_composite_unregister(struct usb_composite_driver *driver)
1840 {
1841         usb_gadget_unregister_driver(&driver->gadget_driver);
1842 }
1843 EXPORT_SYMBOL_GPL(usb_composite_unregister);
1844
1845 /**
1846  * usb_composite_setup_continue() - Continue with the control transfer
1847  * @cdev: the composite device who's control transfer was kept waiting
1848  *
1849  * This function must be called by the USB function driver to continue
1850  * with the control transfer's data/status stage in case it had requested to
1851  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1852  * can request the composite framework to delay the setup request's data/status
1853  * stages by returning USB_GADGET_DELAYED_STATUS.
1854  */
1855 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1856 {
1857         int                     value;
1858         struct usb_request      *req = cdev->req;
1859         unsigned long           flags;
1860
1861         DBG(cdev, "%s\n", __func__);
1862         spin_lock_irqsave(&cdev->lock, flags);
1863
1864         if (cdev->delayed_status == 0) {
1865                 WARN(cdev, "%s: Unexpected call\n", __func__);
1866
1867         } else if (--cdev->delayed_status == 0) {
1868                 DBG(cdev, "%s: Completing delayed status\n", __func__);
1869                 req->length = 0;
1870                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1871                 if (value < 0) {
1872                         DBG(cdev, "ep_queue --> %d\n", value);
1873                         req->status = 0;
1874                         composite_setup_complete(cdev->gadget->ep0, req);
1875                 }
1876         }
1877
1878         spin_unlock_irqrestore(&cdev->lock, flags);
1879 }
1880 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
1881
1882 static char *composite_default_mfr(struct usb_gadget *gadget)
1883 {
1884         char *mfr;
1885         int len;
1886
1887         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
1888                         init_utsname()->release, gadget->name);
1889         len++;
1890         mfr = kmalloc(len, GFP_KERNEL);
1891         if (!mfr)
1892                 return NULL;
1893         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
1894                         init_utsname()->release, gadget->name);
1895         return mfr;
1896 }
1897
1898 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
1899                 struct usb_composite_overwrite *covr)
1900 {
1901         struct usb_device_descriptor    *desc = &cdev->desc;
1902         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
1903         struct usb_string               *dev_str = gstr->strings;
1904
1905         if (covr->idVendor)
1906                 desc->idVendor = cpu_to_le16(covr->idVendor);
1907
1908         if (covr->idProduct)
1909                 desc->idProduct = cpu_to_le16(covr->idProduct);
1910
1911         if (covr->bcdDevice)
1912                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
1913
1914         if (covr->serial_number) {
1915                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
1916                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
1917         }
1918         if (covr->manufacturer) {
1919                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1920                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
1921
1922         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
1923                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1924                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
1925                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
1926         }
1927
1928         if (covr->product) {
1929                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
1930                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
1931         }
1932 }
1933 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
1934
1935 MODULE_LICENSE("GPL");
1936 MODULE_AUTHOR("David Brownell");