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