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