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, 0644);
  44 MODULE_PARM_DESC(idVendor, "USB Vendor ID");
  45
  46 static ushort idProduct;
  47 module_param(idProduct, ushort, 0644);
  48 MODULE_PARM_DESC(idProduct, "USB Product ID");
  49
  50 static ushort bcdDevice;
  51 module_param(bcdDevice, ushort, 0644);
  52 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");
  53
  54 static char *iManufacturer;
  55 module_param(iManufacturer, charp, 0644);
  56 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");
  57
  58 static char *iProduct;
  59 module_param(iProduct, charp, 0644);
  60 MODULE_PARM_DESC(iProduct, "USB Product string");
  61
  62 static char *iSerialNumber;
  63 module_param(iSerialNumber, charp, 0644);
  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_composite_dev        *cdev = get_gadget_data(g);
 121         struct usb_endpoint_descriptor *chosen_desc = NULL;
 122         struct usb_descriptor_header **speed_desc = NULL;
 123
 124         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 125         int want_comp_desc = 0;
 126
 127         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 128
 129         if (!g || !f || !_ep)
 130                 return -EIO;
 131
 132         /* select desired speed */
 133         switch (g->speed) {
 134         case USB_SPEED_SUPER:
 135                 if (gadget_is_superspeed(g)) {
 136                         speed_desc = f->ss_descriptors;
 137                         want_comp_desc = 1;
 138                         break;
 139                 }
 140                 /* else: Fall trough */
 141         case USB_SPEED_HIGH:
 142                 if (gadget_is_dualspeed(g)) {
 143                         speed_desc = f->hs_descriptors;
 144                         break;
 145                 }
 146                 /* else: fall through */
 147         default:
 148                 speed_desc = f->descriptors;
 149         }
 150         /* find descriptors */
 151         for_each_ep_desc(speed_desc, d_spd) {
 152                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 153                 if (chosen_desc->bEndpointAddress == _ep->address)
 154                         goto ep_found;
 155         }
 156         return -EIO;
 157
 158 ep_found:
 159         /* commit results */
 160         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 161         _ep->desc = chosen_desc;
 162         _ep->comp_desc = NULL;
 163         _ep->maxburst = 0;
 164         _ep->mult = 0;
 165         if (!want_comp_desc)
 166                 return 0;
 167
 168         /*
 169          * Companion descriptor should follow EP descriptor
 170          * USB 3.0 spec, #9.6.7
 171          */
 172         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 173         if (!comp_desc ||
 174             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 175                 return -EIO;
 176         _ep->comp_desc = comp_desc;
 177         if (g->speed == USB_SPEED_SUPER) {
 178                 switch (usb_endpoint_type(_ep->desc)) {
 179                 case USB_ENDPOINT_XFER_ISOC:
 180                         /* mult: bits 1:0 of bmAttributes */
 181                         _ep->mult = comp_desc->bmAttributes & 0x3;
 182                 case USB_ENDPOINT_XFER_BULK:
 183                 case USB_ENDPOINT_XFER_INT:
 184                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 185                         break;
 186                 default:
 187                         if (comp_desc->bMaxBurst != 0)
 188                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 189                         _ep->maxburst = 1;
 190                         break;
 191                 }
 192         }
 193         return 0;
 194 }
 195
 196 /**
 197  * usb_add_function() - add a function to a configuration
 198  * @config: the configuration
 199  * @function: the function being added
 200  * Context: single threaded during gadget setup
 201  *
 202  * After initialization, each configuration must have one or more
 203  * functions added to it.  Adding a function involves calling its @bind()
 204  * method to allocate resources such as interface and string identifiers
 205  * and endpoints.
 206  *
 207  * This function returns the value of the function's bind(), which is
 208  * zero for success else a negative errno value.
 209  */
 210 int usb_add_function(struct usb_configuration *config,
 211                 struct usb_function *function)
 212 {
 213         int     value = -EINVAL;
 214
 215         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 216                         function->name, function,
 217                         config->label, config);
 218
 219         if (!function->set_alt || !function->disable)
 220                 goto done;
 221
 222         function->config = config;
 223         list_add_tail(&function->list, &config->functions);
 224
 225         /* REVISIT *require* function->bind? */
 226         if (function->bind) {
 227                 value = function->bind(config, function);
 228                 if (value < 0) {
 229                         list_del(&function->list);
 230                         function->config = NULL;
 231                 }
 232         } else
 233                 value = 0;
 234
 235         /* We allow configurations that don't work at both speeds.
 236          * If we run into a lowspeed Linux system, treat it the same
 237          * as full speed ... it's the function drivers that will need
 238          * to avoid bulk and ISO transfers.
 239          */
 240         if (!config->fullspeed && function->descriptors)
 241                 config->fullspeed = true;
 242         if (!config->highspeed && function->hs_descriptors)
 243                 config->highspeed = true;
 244         if (!config->superspeed && function->ss_descriptors)
 245                 config->superspeed = true;
 246
 247 done:
 248         if (value)
 249                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 250                                 function->name, function, value);
 251         return value;
 252 }
 253
 254 /**
 255  * usb_function_deactivate - prevent function and gadget enumeration
 256  * @function: the function that isn't yet ready to respond
 257  *
 258  * Blocks response of the gadget driver to host enumeration by
 259  * preventing the data line pullup from being activated.  This is
 260  * normally called during @bind() processing to change from the
 261  * initial "ready to respond" state, or when a required resource
 262  * becomes available.
 263  *
 264  * For example, drivers that serve as a passthrough to a userspace
 265  * daemon can block enumeration unless that daemon (such as an OBEX,
 266  * MTP, or print server) is ready to handle host requests.
 267  *
 268  * Not all systems support software control of their USB peripheral
 269  * data pullups.
 270  *
 271  * Returns zero on success, else negative errno.
 272  */
 273 int usb_function_deactivate(struct usb_function *function)
 274 {
 275         struct usb_composite_dev        *cdev = function->config->cdev;
 276         unsigned long                   flags;
 277         int                             status = 0;
 278
 279         spin_lock_irqsave(&cdev->lock, flags);
 280
 281         if (cdev->deactivations == 0)
 282                 status = usb_gadget_disconnect(cdev->gadget);
 283         if (status == 0)
 284                 cdev->deactivations++;
 285
 286         spin_unlock_irqrestore(&cdev->lock, flags);
 287         return status;
 288 }
 289
 290 /**
 291  * usb_function_activate - allow function and gadget enumeration
 292  * @function: function on which usb_function_activate() was called
 293  *
 294  * Reverses effect of usb_function_deactivate().  If no more functions
 295  * are delaying their activation, the gadget driver will respond to
 296  * host enumeration procedures.
 297  *
 298  * Returns zero on success, else negative errno.
 299  */
 300 int usb_function_activate(struct usb_function *function)
 301 {
 302         struct usb_composite_dev        *cdev = function->config->cdev;
 303         int                             status = 0;
 304
 305         spin_lock(&cdev->lock);
 306
 307         if (WARN_ON(cdev->deactivations == 0))
 308                 status = -EINVAL;
 309         else {
 310                 cdev->deactivations--;
 311                 if (cdev->deactivations == 0)
 312                         status = usb_gadget_connect(cdev->gadget);
 313         }
 314
 315         spin_unlock(&cdev->lock);
 316         return status;
 317 }
 318
 319 /**
 320  * usb_interface_id() - allocate an unused interface ID
 321  * @config: configuration associated with the interface
 322  * @function: function handling the interface
 323  * Context: single threaded during gadget setup
 324  *
 325  * usb_interface_id() is called from usb_function.bind() callbacks to
 326  * allocate new interface IDs.  The function driver will then store that
 327  * ID in interface, association, CDC union, and other descriptors.  It
 328  * will also handle any control requests targeted at that interface,
 329  * particularly changing its altsetting via set_alt().  There may
 330  * also be class-specific or vendor-specific requests to handle.
 331  *
 332  * All interface identifier should be allocated using this routine, to
 333  * ensure that for example different functions don't wrongly assign
 334  * different meanings to the same identifier.  Note that since interface
 335  * identifiers are configuration-specific, functions used in more than
 336  * one configuration (or more than once in a given configuration) need
 337  * multiple versions of the relevant descriptors.
 338  *
 339  * Returns the interface ID which was allocated; or -ENODEV if no
 340  * more interface IDs can be allocated.
 341  */
 342 int usb_interface_id(struct usb_configuration *config,
 343                 struct usb_function *function)
 344 {
 345         unsigned id = config->next_interface_id;
 346
 347         if (id < MAX_CONFIG_INTERFACES) {
 348                 config->interface[id] = function;
 349                 config->next_interface_id = id + 1;
 350                 return id;
 351         }
 352         return -ENODEV;
 353 }
 354
 355 static int config_buf(struct usb_configuration *config,
 356                 enum usb_device_speed speed, void *buf, u8 type)
 357 {
 358         struct usb_config_descriptor    *c = buf;
 359         void                            *next = buf + USB_DT_CONFIG_SIZE;
 360         int                             len = USB_BUFSIZ - USB_DT_CONFIG_SIZE;
 361         struct usb_function             *f;
 362         int                             status;
 363
 364         /* write the config descriptor */
 365         c = buf;
 366         c->bLength = USB_DT_CONFIG_SIZE;
 367         c->bDescriptorType = type;
 368         /* wTotalLength is written later */
 369         c->bNumInterfaces = config->next_interface_id;
 370         c->bConfigurationValue = config->bConfigurationValue;
 371         c->iConfiguration = config->iConfiguration;
 372         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 373         c->bMaxPower = config->bMaxPower ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
 374
 375         /* There may be e.g. OTG descriptors */
 376         if (config->descriptors) {
 377                 status = usb_descriptor_fillbuf(next, len,
 378                                 config->descriptors);
 379                 if (status < 0)
 380                         return status;
 381                 len -= status;
 382                 next += status;
 383         }
 384
 385         /* add each function's descriptors */
 386         list_for_each_entry(f, &config->functions, list) {
 387                 struct usb_descriptor_header **descriptors;
 388
 389                 switch (speed) {
 390                 case USB_SPEED_SUPER:
 391                         descriptors = f->ss_descriptors;
 392                         break;
 393                 case USB_SPEED_HIGH:
 394                         descriptors = f->hs_descriptors;
 395                         break;
 396                 default:
 397                         descriptors = f->descriptors;
 398                 }
 399
 400                 if (!descriptors)
 401                         continue;
 402                 status = usb_descriptor_fillbuf(next, len,
 403                         (const struct usb_descriptor_header **) descriptors);
 404                 if (status < 0)
 405                         return status;
 406                 len -= status;
 407                 next += status;
 408         }
 409
 410         len = next - buf;
 411         c->wTotalLength = cpu_to_le16(len);
 412         return len;
 413 }
 414
 415 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 416 {
 417         struct usb_gadget               *gadget = cdev->gadget;
 418         struct usb_configuration        *c;
 419         u8                              type = w_value >> 8;
 420         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 421
 422         if (gadget->speed == USB_SPEED_SUPER)
 423                 speed = gadget->speed;
 424         else if (gadget_is_dualspeed(gadget)) {
 425                 int     hs = 0;
 426                 if (gadget->speed == USB_SPEED_HIGH)
 427                         hs = 1;
 428                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 429                         hs = !hs;
 430                 if (hs)
 431                         speed = USB_SPEED_HIGH;
 432
 433         }
 434
 435         /* This is a lookup by config *INDEX* */
 436         w_value &= 0xff;
 437         list_for_each_entry(c, &cdev->configs, list) {
 438                 /* ignore configs that won't work at this speed */
 439                 switch (speed) {
 440                 case USB_SPEED_SUPER:
 441                         if (!c->superspeed)
 442                                 continue;
 443                         break;
 444                 case USB_SPEED_HIGH:
 445                         if (!c->highspeed)
 446                                 continue;
 447                         break;
 448                 default:
 449                         if (!c->fullspeed)
 450                                 continue;
 451                 }
 452
 453                 if (w_value == 0)
 454                         return config_buf(c, speed, cdev->req->buf, type);
 455                 w_value--;
 456         }
 457         return -EINVAL;
 458 }
 459
 460 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 461 {
 462         struct usb_gadget               *gadget = cdev->gadget;
 463         struct usb_configuration        *c;
 464         unsigned                        count = 0;
 465         int                             hs = 0;
 466         int                             ss = 0;
 467
 468         if (gadget_is_dualspeed(gadget)) {
 469                 if (gadget->speed == USB_SPEED_HIGH)
 470                         hs = 1;
 471                 if (gadget->speed == USB_SPEED_SUPER)
 472                         ss = 1;
 473                 if (type == USB_DT_DEVICE_QUALIFIER)
 474                         hs = !hs;
 475         }
 476         list_for_each_entry(c, &cdev->configs, list) {
 477                 /* ignore configs that won't work at this speed */
 478                 if (ss) {
 479                         if (!c->superspeed)
 480                                 continue;
 481                 } else if (hs) {
 482                         if (!c->highspeed)
 483                                 continue;
 484                 } else {
 485                         if (!c->fullspeed)
 486                                 continue;
 487                 }
 488                 count++;
 489         }
 490         return count;
 491 }
 492
 493 /**
 494  * bos_desc() - prepares the BOS descriptor.
 495  * @cdev: pointer to usb_composite device to generate the bos
 496  *      descriptor for
 497  *
 498  * This function generates the BOS (Binary Device Object)
 499  * descriptor and its device capabilities descriptors. The BOS
 500  * descriptor should be supported by a SuperSpeed device.
 501  */
 502 static int bos_desc(struct usb_composite_dev *cdev)
 503 {
 504         struct usb_ext_cap_descriptor   *usb_ext;
 505         struct usb_ss_cap_descriptor    *ss_cap;
 506         struct usb_dcd_config_params    dcd_config_params;
 507         struct usb_bos_descriptor       *bos = cdev->req->buf;
 508
 509         bos->bLength = USB_DT_BOS_SIZE;
 510         bos->bDescriptorType = USB_DT_BOS;
 511
 512         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 513         bos->bNumDeviceCaps = 0;
 514
 515         /*
 516          * A SuperSpeed device shall include the USB2.0 extension descriptor
 517          * and shall support LPM when operating in USB2.0 HS mode.
 518          */
 519         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 520         bos->bNumDeviceCaps++;
 521         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 522         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 523         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 524         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 525         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
 526
 527         /*
 528          * The Superspeed USB Capability descriptor shall be implemented by all
 529          * SuperSpeed devices.
 530          */
 531         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 532         bos->bNumDeviceCaps++;
 533         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 534         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 535         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 536         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 537         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 538         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 539                                 USB_FULL_SPEED_OPERATION |
 540                                 USB_HIGH_SPEED_OPERATION |
 541                                 USB_5GBPS_OPERATION);
 542         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 543
 544         /* Get Controller configuration */
 545         if (cdev->gadget->ops->get_config_params)
 546                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 547         else {
 548                 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
 549                 dcd_config_params.bU2DevExitLat =
 550                         cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 551         }
 552         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 553         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 554
 555         return le16_to_cpu(bos->wTotalLength);
 556 }
 557
 558 static void device_qual(struct usb_composite_dev *cdev)
 559 {
 560         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 561
 562         qual->bLength = sizeof(*qual);
 563         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 564         /* POLICY: same bcdUSB and device type info at both speeds */
 565         qual->bcdUSB = cdev->desc.bcdUSB;
 566         qual->bDeviceClass = cdev->desc.bDeviceClass;
 567         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 568         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 569         /* ASSUME same EP0 fifo size at both speeds */
 570         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 571         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 572         qual->bRESERVED = 0;
 573 }
 574
 575 /*-------------------------------------------------------------------------*/
 576
 577 static void reset_config(struct usb_composite_dev *cdev)
 578 {
 579         struct usb_function             *f;
 580
 581         DBG(cdev, "reset config\n");
 582
 583         list_for_each_entry(f, &cdev->config->functions, list) {
 584                 if (f->disable)
 585                         f->disable(f);
 586
 587                 bitmap_zero(f->endpoints, 32);
 588         }
 589         cdev->config = NULL;
 590 }
 591
 592 static int set_config(struct usb_composite_dev *cdev,
 593                 const struct usb_ctrlrequest *ctrl, unsigned number)
 594 {
 595         struct usb_gadget       *gadget = cdev->gadget;
 596         struct usb_configuration *c = NULL;
 597         int                     result = -EINVAL;
 598         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 599         int                     tmp;
 600
 601         if (number) {
 602                 list_for_each_entry(c, &cdev->configs, list) {
 603                         if (c->bConfigurationValue == number) {
 604                                 /*
 605                                  * We disable the FDs of the previous
 606                                  * configuration only if the new configuration
 607                                  * is a valid one
 608                                  */
 609                                 if (cdev->config)
 610                                         reset_config(cdev);
 611                                 result = 0;
 612                                 break;
 613                         }
 614                 }
 615                 if (result < 0)
 616                         goto done;
 617         } else { /* Zero configuration value - need to reset the config */
 618                 if (cdev->config)
 619                         reset_config(cdev);
 620                 result = 0;
 621         }
 622
 623         INFO(cdev, "%s config #%d: %s\n",
 624              usb_speed_string(gadget->speed),
 625              number, c ? c->label : "unconfigured");
 626
 627         if (!c)
 628                 goto done;
 629
 630         cdev->config = c;
 631
 632         /* Initialize all interfaces by setting them to altsetting zero. */
 633         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 634                 struct usb_function     *f = c->interface[tmp];
 635                 struct usb_descriptor_header **descriptors;
 636
 637                 if (!f)
 638                         break;
 639
 640                 /*
 641                  * Record which endpoints are used by the function. This is used
 642                  * to dispatch control requests targeted at that endpoint to the
 643                  * function's setup callback instead of the current
 644                  * configuration's setup callback.
 645                  */
 646                 switch (gadget->speed) {
 647                 case USB_SPEED_SUPER:
 648                         descriptors = f->ss_descriptors;
 649                         break;
 650                 case USB_SPEED_HIGH:
 651                         descriptors = f->hs_descriptors;
 652                         break;
 653                 default:
 654                         descriptors = f->descriptors;
 655                 }
 656
 657                 for (; *descriptors; ++descriptors) {
 658                         struct usb_endpoint_descriptor *ep;
 659                         int addr;
 660
 661                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 662                                 continue;
 663
 664                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 665                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 666                              |  (ep->bEndpointAddress & 0x0f);
 667                         set_bit(addr, f->endpoints);
 668                 }
 669
 670                 result = f->set_alt(f, tmp, 0);
 671                 if (result < 0) {
 672                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 673                                         tmp, f->name, f, result);
 674
 675                         reset_config(cdev);
 676                         goto done;
 677                 }
 678
 679                 if (result == USB_GADGET_DELAYED_STATUS) {
 680                         DBG(cdev,
 681                          "%s: interface %d (%s) requested delayed status\n",
 682                                         __func__, tmp, f->name);
 683                         cdev->delayed_status++;
 684                         DBG(cdev, "delayed_status count %d\n",
 685                                         cdev->delayed_status);
 686                 }
 687         }
 688
 689         /* when we return, be sure our power usage is valid */
 690         power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
 691 done:
 692         usb_gadget_vbus_draw(gadget, power);
 693         if (result >= 0 && cdev->delayed_status)
 694                 result = USB_GADGET_DELAYED_STATUS;
 695         return result;
 696 }
 697
 698 /**
 699  * usb_add_config() - add a configuration to a device.
 700  * @cdev: wraps the USB gadget
 701  * @config: the configuration, with bConfigurationValue assigned
 702  * @bind: the configuration's bind function
 703  * Context: single threaded during gadget setup
 704  *
 705  * One of the main tasks of a composite @bind() routine is to
 706  * add each of the configurations it supports, using this routine.
 707  *
 708  * This function returns the value of the configuration's @bind(), which
 709  * is zero for success else a negative errno value.  Binding configurations
 710  * assigns global resources including string IDs, and per-configuration
 711  * resources such as interface IDs and endpoints.
 712  */
 713 int usb_add_config(struct usb_composite_dev *cdev,
 714                 struct usb_configuration *config,
 715                 int (*bind)(struct usb_configuration *))
 716 {
 717         int                             status = -EINVAL;
 718         struct usb_configuration        *c;
 719
 720         DBG(cdev, "adding config #%u '%s'/%p\n",
 721                         config->bConfigurationValue,
 722                         config->label, config);
 723
 724         if (!config->bConfigurationValue || !bind)
 725                 goto done;
 726
 727         /* Prevent duplicate configuration identifiers */
 728         list_for_each_entry(c, &cdev->configs, list) {
 729                 if (c->bConfigurationValue == config->bConfigurationValue) {
 730                         status = -EBUSY;
 731                         goto done;
 732                 }
 733         }
 734
 735         config->cdev = cdev;
 736         list_add_tail(&config->list, &cdev->configs);
 737
 738         INIT_LIST_HEAD(&config->functions);
 739         config->next_interface_id = 0;
 740         memset(config->interface, 0, sizeof(config->interface));
 741
 742         status = bind(config);
 743         if (status < 0) {
 744                 while (!list_empty(&config->functions)) {
 745                         struct usb_function             *f;
 746
 747                         f = list_first_entry(&config->functions,
 748                                         struct usb_function, list);
 749                         list_del(&f->list);
 750                         if (f->unbind) {
 751                                 DBG(cdev, "unbind function '%s'/%p\n",
 752                                         f->name, f);
 753                                 f->unbind(config, f);
 754                                 /* may free memory for "f" */
 755                         }
 756                 }
 757                 list_del(&config->list);
 758                 config->cdev = NULL;
 759         } else {
 760                 unsigned        i;
 761
 762                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 763                         config->bConfigurationValue, config,
 764                         config->superspeed ? " super" : "",
 765                         config->highspeed ? " high" : "",
 766                         config->fullspeed
 767                                 ? (gadget_is_dualspeed(cdev->gadget)
 768                                         ? " full"
 769                                         : " full/low")
 770                                 : "");
 771
 772                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 773                         struct usb_function     *f = config->interface[i];
 774
 775                         if (!f)
 776                                 continue;
 777                         DBG(cdev, "  interface %d = %s/%p\n",
 778                                 i, f->name, f);
 779                 }
 780         }
 781
 782         /* set_alt(), or next bind(), sets up
 783          * ep->driver_data as needed.
 784          */
 785         usb_ep_autoconfig_reset(cdev->gadget);
 786
 787 done:
 788         if (status)
 789                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 790                                 config->bConfigurationValue, status);
 791         return status;
 792 }
 793
 794 static void remove_config(struct usb_composite_dev *cdev,
 795                               struct usb_configuration *config)
 796 {
 797         while (!list_empty(&config->functions)) {
 798                 struct usb_function             *f;
 799
 800                 f = list_first_entry(&config->functions,
 801                                 struct usb_function, list);
 802                 list_del(&f->list);
 803                 if (f->unbind) {
 804                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 805                         f->unbind(config, f);
 806                         /* may free memory for "f" */
 807                 }
 808         }
 809         list_del(&config->list);
 810         if (config->unbind) {
 811                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 812                 config->unbind(config);
 813                         /* may free memory for "c" */
 814         }
 815 }
 816
 817 /**
 818  * usb_remove_config() - remove a configuration from a device.
 819  * @cdev: wraps the USB gadget
 820  * @config: the configuration
 821  *
 822  * Drivers must call usb_gadget_disconnect before calling this function
 823  * to disconnect the device from the host and make sure the host will not
 824  * try to enumerate the device while we are changing the config list.
 825  */
 826 void usb_remove_config(struct usb_composite_dev *cdev,
 827                       struct usb_configuration *config)
 828 {
 829         unsigned long flags;
 830
 831         spin_lock_irqsave(&cdev->lock, flags);
 832
 833         if (cdev->config == config)
 834                 reset_config(cdev);
 835
 836         spin_unlock_irqrestore(&cdev->lock, flags);
 837
 838         remove_config(cdev, config);
 839 }
 840
 841 /*-------------------------------------------------------------------------*/
 842
 843 /* We support strings in multiple languages ... string descriptor zero
 844  * says which languages are supported.  The typical case will be that
 845  * only one language (probably English) is used, with I18N handled on
 846  * the host side.
 847  */
 848
 849 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 850 {
 851         const struct usb_gadget_strings *s;
 852         __le16                          language;
 853         __le16                          *tmp;
 854
 855         while (*sp) {
 856                 s = *sp;
 857                 language = cpu_to_le16(s->language);
 858                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 859                         if (*tmp == language)
 860                                 goto repeat;
 861                 }
 862                 *tmp++ = language;
 863 repeat:
 864                 sp++;
 865         }
 866 }
 867
 868 static int lookup_string(
 869         struct usb_gadget_strings       **sp,
 870         void                            *buf,
 871         u16                             language,
 872         int                             id
 873 )
 874 {
 875         struct usb_gadget_strings       *s;
 876         int                             value;
 877
 878         while (*sp) {
 879                 s = *sp++;
 880                 if (s->language != language)
 881                         continue;
 882                 value = usb_gadget_get_string(s, id, buf);
 883                 if (value > 0)
 884                         return value;
 885         }
 886         return -EINVAL;
 887 }
 888
 889 static int get_string(struct usb_composite_dev *cdev,
 890                 void *buf, u16 language, int id)
 891 {
 892         struct usb_configuration        *c;
 893         struct usb_function             *f;
 894         int                             len;
 895         const char                      *str;
 896
 897         /* Yes, not only is USB's I18N support probably more than most
 898          * folk will ever care about ... also, it's all supported here.
 899          * (Except for UTF8 support for Unicode's "Astral Planes".)
 900          */
 901
 902         /* 0 == report all available language codes */
 903         if (id == 0) {
 904                 struct usb_string_descriptor    *s = buf;
 905                 struct usb_gadget_strings       **sp;
 906
 907                 memset(s, 0, 256);
 908                 s->bDescriptorType = USB_DT_STRING;
 909
 910                 sp = composite->strings;
 911                 if (sp)
 912                         collect_langs(sp, s->wData);
 913
 914                 list_for_each_entry(c, &cdev->configs, list) {
 915                         sp = c->strings;
 916                         if (sp)
 917                                 collect_langs(sp, s->wData);
 918
 919                         list_for_each_entry(f, &c->functions, list) {
 920                                 sp = f->strings;
 921                                 if (sp)
 922                                         collect_langs(sp, s->wData);
 923                         }
 924                 }
 925
 926                 for (len = 0; len <= 126 && s->wData[len]; len++)
 927                         continue;
 928                 if (!len)
 929                         return -EINVAL;
 930
 931                 s->bLength = 2 * (len + 1);
 932                 return s->bLength;
 933         }
 934
 935         /* Otherwise, look up and return a specified string.  First
 936          * check if the string has not been overridden.
 937          */
 938         if (cdev->manufacturer_override == id)
 939                 str = iManufacturer ?: composite->iManufacturer ?:
 940                         composite_manufacturer;
 941         else if (cdev->product_override == id)
 942                 str = iProduct ?: composite->iProduct;
 943         else if (cdev->serial_override == id)
 944                 str = iSerialNumber ?: composite->iSerialNumber;
 945         else
 946                 str = NULL;
 947         if (str) {
 948                 struct usb_gadget_strings strings = {
 949                         .language = language,
 950                         .strings  = &(struct usb_string) { 0xff, str }
 951                 };
 952                 return usb_gadget_get_string(&strings, 0xff, buf);
 953         }
 954
 955         /* String IDs are device-scoped, so we look up each string
 956          * table we're told about.  These lookups are infrequent;
 957          * simpler-is-better here.
 958          */
 959         if (composite->strings) {
 960                 len = lookup_string(composite->strings, buf, language, id);
 961                 if (len > 0)
 962                         return len;
 963         }
 964         list_for_each_entry(c, &cdev->configs, list) {
 965                 if (c->strings) {
 966                         len = lookup_string(c->strings, buf, language, id);
 967                         if (len > 0)
 968                                 return len;
 969                 }
 970                 list_for_each_entry(f, &c->functions, list) {
 971                         if (!f->strings)
 972                                 continue;
 973                         len = lookup_string(f->strings, buf, language, id);
 974                         if (len > 0)
 975                                 return len;
 976                 }
 977         }
 978         return -EINVAL;
 979 }
 980
 981 /**
 982  * usb_string_id() - allocate an unused string ID
 983  * @cdev: the device whose string descriptor IDs are being allocated
 984  * Context: single threaded during gadget setup
 985  *
 986  * @usb_string_id() is called from bind() callbacks to allocate
 987  * string IDs.  Drivers for functions, configurations, or gadgets will
 988  * then store that ID in the appropriate descriptors and string table.
 989  *
 990  * All string identifier should be allocated using this,
 991  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
 992  * that for example different functions don't wrongly assign different
 993  * meanings to the same identifier.
 994  */
 995 int usb_string_id(struct usb_composite_dev *cdev)
 996 {
 997         if (cdev->next_string_id < 254) {
 998                 /* string id 0 is reserved by USB spec for list of
 999                  * supported languages */
1000                 /* 255 reserved as well? -- mina86 */
1001                 cdev->next_string_id++;
1002                 return cdev->next_string_id;
1003         }
1004         return -ENODEV;
1005 }
1006
1007 /**
1008  * usb_string_ids() - allocate unused string IDs in batch
1009  * @cdev: the device whose string descriptor IDs are being allocated
1010  * @str: an array of usb_string objects to assign numbers to
1011  * Context: single threaded during gadget setup
1012  *
1013  * @usb_string_ids() is called from bind() callbacks to allocate
1014  * string IDs.  Drivers for functions, configurations, or gadgets will
1015  * then copy IDs from the string table to the appropriate descriptors
1016  * and string table for other languages.
1017  *
1018  * All string identifier should be allocated using this,
1019  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1020  * example different functions don't wrongly assign different meanings
1021  * to the same identifier.
1022  */
1023 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1024 {
1025         int next = cdev->next_string_id;
1026
1027         for (; str->s; ++str) {
1028                 if (unlikely(next >= 254))
1029                         return -ENODEV;
1030                 str->id = ++next;
1031         }
1032
1033         cdev->next_string_id = next;
1034
1035         return 0;
1036 }
1037
1038 /**
1039  * usb_string_ids_n() - allocate unused string IDs in batch
1040  * @c: the device whose string descriptor IDs are being allocated
1041  * @n: number of string IDs to allocate
1042  * Context: single threaded during gadget setup
1043  *
1044  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1045  * valid IDs.  At least provided that @n is non-zero because if it
1046  * is, returns last requested ID which is now very useful information.
1047  *
1048  * @usb_string_ids_n() is called from bind() callbacks to allocate
1049  * string IDs.  Drivers for functions, configurations, or gadgets will
1050  * then store that ID in the appropriate descriptors and string table.
1051  *
1052  * All string identifier should be allocated using this,
1053  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1054  * example different functions don't wrongly assign different meanings
1055  * to the same identifier.
1056  */
1057 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1058 {
1059         unsigned next = c->next_string_id;
1060         if (unlikely(n > 254 || (unsigned)next + n > 254))
1061                 return -ENODEV;
1062         c->next_string_id += n;
1063         return next + 1;
1064 }
1065
1066
1067 /*-------------------------------------------------------------------------*/
1068
1069 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1070 {
1071         if (req->status || req->actual != req->length)
1072                 DBG((struct usb_composite_dev *) ep->driver_data,
1073                                 "setup complete --> %d, %d/%d\n",
1074                                 req->status, req->actual, req->length);
1075 }
1076
1077 /*
1078  * The setup() callback implements all the ep0 functionality that's
1079  * not handled lower down, in hardware or the hardware driver(like
1080  * device and endpoint feature flags, and their status).  It's all
1081  * housekeeping for the gadget function we're implementing.  Most of
1082  * the work is in config and function specific setup.
1083  */
1084 static int
1085 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1086 {
1087         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1088         struct usb_request              *req = cdev->req;
1089         int                             value = -EOPNOTSUPP;
1090         int                             status = 0;
1091         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1092         u8                              intf = w_index & 0xFF;
1093         u16                             w_value = le16_to_cpu(ctrl->wValue);
1094         u16                             w_length = le16_to_cpu(ctrl->wLength);
1095         struct usb_function             *f = NULL;
1096         u8                              endp;
1097
1098         /* partial re-init of the response message; the function or the
1099          * gadget might need to intercept e.g. a control-OUT completion
1100          * when we delegate to it.
1101          */
1102         req->zero = 0;
1103         req->complete = composite_setup_complete;
1104         req->length = 0;
1105         gadget->ep0->driver_data = cdev;
1106
1107         switch (ctrl->bRequest) {
1108
1109         /* we handle all standard USB descriptors */
1110         case USB_REQ_GET_DESCRIPTOR:
1111                 if (ctrl->bRequestType != USB_DIR_IN)
1112                         goto unknown;
1113                 switch (w_value >> 8) {
1114
1115                 case USB_DT_DEVICE:
1116                         cdev->desc.bNumConfigurations =
1117                                 count_configs(cdev, USB_DT_DEVICE);
1118                         cdev->desc.bMaxPacketSize0 =
1119                                 cdev->gadget->ep0->maxpacket;
1120                         if (gadget_is_superspeed(gadget)) {
1121                                 if (gadget->speed >= USB_SPEED_SUPER) {
1122                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1123                                         cdev->desc.bMaxPacketSize0 = 9;
1124                                 } else {
1125                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1126                                 }
1127                         }
1128
1129                         value = min(w_length, (u16) sizeof cdev->desc);
1130                         memcpy(req->buf, &cdev->desc, value);
1131                         break;
1132                 case USB_DT_DEVICE_QUALIFIER:
1133                         if (!gadget_is_dualspeed(gadget) ||
1134                             gadget->speed >= USB_SPEED_SUPER)
1135                                 break;
1136                         device_qual(cdev);
1137                         value = min_t(int, w_length,
1138                                 sizeof(struct usb_qualifier_descriptor));
1139                         break;
1140                 case USB_DT_OTHER_SPEED_CONFIG:
1141                         if (!gadget_is_dualspeed(gadget) ||
1142                             gadget->speed >= USB_SPEED_SUPER)
1143                                 break;
1144                         /* FALLTHROUGH */
1145                 case USB_DT_CONFIG:
1146                         value = config_desc(cdev, w_value);
1147                         if (value >= 0)
1148                                 value = min(w_length, (u16) value);
1149                         break;
1150                 case USB_DT_STRING:
1151                         value = get_string(cdev, req->buf,
1152                                         w_index, w_value & 0xff);
1153                         if (value >= 0)
1154                                 value = min(w_length, (u16) value);
1155                         break;
1156                 case USB_DT_BOS:
1157                         if (gadget_is_superspeed(gadget)) {
1158                                 value = bos_desc(cdev);
1159                                 value = min(w_length, (u16) value);
1160                         }
1161                         break;
1162                 }
1163                 break;
1164
1165         /* any number of configs can work */
1166         case USB_REQ_SET_CONFIGURATION:
1167                 if (ctrl->bRequestType != 0)
1168                         goto unknown;
1169                 if (gadget_is_otg(gadget)) {
1170                         if (gadget->a_hnp_support)
1171                                 DBG(cdev, "HNP available\n");
1172                         else if (gadget->a_alt_hnp_support)
1173                                 DBG(cdev, "HNP on another port\n");
1174                         else
1175                                 VDBG(cdev, "HNP inactive\n");
1176                 }
1177                 spin_lock(&cdev->lock);
1178                 value = set_config(cdev, ctrl, w_value);
1179                 spin_unlock(&cdev->lock);
1180                 break;
1181         case USB_REQ_GET_CONFIGURATION:
1182                 if (ctrl->bRequestType != USB_DIR_IN)
1183                         goto unknown;
1184                 if (cdev->config)
1185                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1186                 else
1187                         *(u8 *)req->buf = 0;
1188                 value = min(w_length, (u16) 1);
1189                 break;
1190
1191         /* function drivers must handle get/set altsetting; if there's
1192          * no get() method, we know only altsetting zero works.
1193          */
1194         case USB_REQ_SET_INTERFACE:
1195                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1196                         goto unknown;
1197                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1198                         break;
1199                 f = cdev->config->interface[intf];
1200                 if (!f)
1201                         break;
1202                 if (w_value && !f->set_alt)
1203                         break;
1204                 value = f->set_alt(f, w_index, w_value);
1205                 if (value == USB_GADGET_DELAYED_STATUS) {
1206                         DBG(cdev,
1207                          "%s: interface %d (%s) requested delayed status\n",
1208                                         __func__, intf, f->name);
1209                         cdev->delayed_status++;
1210                         DBG(cdev, "delayed_status count %d\n",
1211                                         cdev->delayed_status);
1212                 }
1213                 break;
1214         case USB_REQ_GET_INTERFACE:
1215                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1216                         goto unknown;
1217                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1218                         break;
1219                 f = cdev->config->interface[intf];
1220                 if (!f)
1221                         break;
1222                 /* lots of interfaces only need altsetting zero... */
1223                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1224                 if (value < 0)
1225                         break;
1226                 *((u8 *)req->buf) = value;
1227                 value = min(w_length, (u16) 1);
1228                 break;
1229
1230         /*
1231          * USB 3.0 additions:
1232          * Function driver should handle get_status request. If such cb
1233          * wasn't supplied we respond with default value = 0
1234          * Note: function driver should supply such cb only for the first
1235          * interface of the function
1236          */
1237         case USB_REQ_GET_STATUS:
1238                 if (!gadget_is_superspeed(gadget))
1239                         goto unknown;
1240                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1241                         goto unknown;
1242                 value = 2;      /* This is the length of the get_status reply */
1243                 put_unaligned_le16(0, req->buf);
1244                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1245                         break;
1246                 f = cdev->config->interface[intf];
1247                 if (!f)
1248                         break;
1249                 status = f->get_status ? f->get_status(f) : 0;
1250                 if (status < 0)
1251                         break;
1252                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1253                 break;
1254         /*
1255          * Function drivers should handle SetFeature/ClearFeature
1256          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1257          * only for the first interface of the function
1258          */
1259         case USB_REQ_CLEAR_FEATURE:
1260         case USB_REQ_SET_FEATURE:
1261                 if (!gadget_is_superspeed(gadget))
1262                         goto unknown;
1263                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1264                         goto unknown;
1265                 switch (w_value) {
1266                 case USB_INTRF_FUNC_SUSPEND:
1267                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1268                                 break;
1269                         f = cdev->config->interface[intf];
1270                         if (!f)
1271                                 break;
1272                         value = 0;
1273                         if (f->func_suspend)
1274                                 value = f->func_suspend(f, w_index >> 8);
1275                         if (value < 0) {
1276                                 ERROR(cdev,
1277                                       "func_suspend() returned error %d\n",
1278                                       value);
1279                                 value = 0;
1280                         }
1281                         break;
1282                 }
1283                 break;
1284         default:
1285 unknown:
1286                 VDBG(cdev,
1287                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1288                         ctrl->bRequestType, ctrl->bRequest,
1289                         w_value, w_index, w_length);
1290
1291                 /* functions always handle their interfaces and endpoints...
1292                  * punt other recipients (other, WUSB, ...) to the current
1293                  * configuration code.
1294                  *
1295                  * REVISIT it could make sense to let the composite device
1296                  * take such requests too, if that's ever needed:  to work
1297                  * in config 0, etc.
1298                  */
1299                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1300                 case USB_RECIP_INTERFACE:
1301                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1302                                 break;
1303                         f = cdev->config->interface[intf];
1304                         break;
1305
1306                 case USB_RECIP_ENDPOINT:
1307                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1308                         list_for_each_entry(f, &cdev->config->functions, list) {
1309                                 if (test_bit(endp, f->endpoints))
1310                                         break;
1311                         }
1312                         if (&f->list == &cdev->config->functions)
1313                                 f = NULL;
1314                         break;
1315                 }
1316
1317                 if (f && f->setup)
1318                         value = f->setup(f, ctrl);
1319                 else {
1320                         struct usb_configuration        *c;
1321
1322                         c = cdev->config;
1323                         if (c && c->setup)
1324                                 value = c->setup(c, ctrl);
1325                 }
1326
1327                 goto done;
1328         }
1329
1330         /* respond with data transfer before status phase? */
1331         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1332                 req->length = value;
1333                 req->zero = value < w_length;
1334                 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1335                 if (value < 0) {
1336                         DBG(cdev, "ep_queue --> %d\n", value);
1337                         req->status = 0;
1338                         composite_setup_complete(gadget->ep0, req);
1339                 }
1340         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1341                 WARN(cdev,
1342                         "%s: Delayed status not supported for w_length != 0",
1343                         __func__);
1344         }
1345
1346 done:
1347         /* device either stalls (value < 0) or reports success */
1348         return value;
1349 }
1350
1351 static void composite_disconnect(struct usb_gadget *gadget)
1352 {
1353         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1354         unsigned long                   flags;
1355
1356         /* REVISIT:  should we have config and device level
1357          * disconnect callbacks?
1358          */
1359         spin_lock_irqsave(&cdev->lock, flags);
1360         if (cdev->config)
1361                 reset_config(cdev);
1362         if (composite->disconnect)
1363                 composite->disconnect(cdev);
1364         spin_unlock_irqrestore(&cdev->lock, flags);
1365 }
1366
1367 /*-------------------------------------------------------------------------*/
1368
1369 static ssize_t composite_show_suspended(struct device *dev,
1370                                         struct device_attribute *attr,
1371                                         char *buf)
1372 {
1373         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1374         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1375
1376         return sprintf(buf, "%d\n", cdev->suspended);
1377 }
1378
1379 static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
1380
1381 static void
1382 composite_unbind(struct usb_gadget *gadget)
1383 {
1384         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1385
1386         /* composite_disconnect() must already have been called
1387          * by the underlying peripheral controller driver!
1388          * so there's no i/o concurrency that could affect the
1389          * state protected by cdev->lock.
1390          */
1391         WARN_ON(cdev->config);
1392
1393         while (!list_empty(&cdev->configs)) {
1394                 struct usb_configuration        *c;
1395                 c = list_first_entry(&cdev->configs,
1396                                 struct usb_configuration, list);
1397                 remove_config(cdev, c);
1398         }
1399         if (composite->unbind)
1400                 composite->unbind(cdev);
1401
1402         if (cdev->req) {
1403                 kfree(cdev->req->buf);
1404                 usb_ep_free_request(gadget->ep0, cdev->req);
1405         }
1406         device_remove_file(&gadget->dev, &dev_attr_suspended);
1407         kfree(cdev);
1408         set_gadget_data(gadget, NULL);
1409         composite = NULL;
1410 }
1411
1412 static u8 override_id(struct usb_composite_dev *cdev, u8 *desc)
1413 {
1414         if (!*desc) {
1415                 int ret = usb_string_id(cdev);
1416                 if (unlikely(ret < 0))
1417                         WARNING(cdev, "failed to override string ID\n");
1418                 else
1419                         *desc = ret;
1420         }
1421
1422         return *desc;
1423 }
1424
1425 static int composite_bind(struct usb_gadget *gadget)
1426 {
1427         struct usb_composite_dev        *cdev;
1428         int                             status = -ENOMEM;
1429
1430         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1431         if (!cdev)
1432                 return status;
1433
1434         spin_lock_init(&cdev->lock);
1435         cdev->gadget = gadget;
1436         set_gadget_data(gadget, cdev);
1437         INIT_LIST_HEAD(&cdev->configs);
1438
1439         /* preallocate control response and buffer */
1440         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1441         if (!cdev->req)
1442                 goto fail;
1443         cdev->req->buf = kmalloc(USB_BUFSIZ, GFP_KERNEL);
1444         if (!cdev->req->buf)
1445                 goto fail;
1446         cdev->req->complete = composite_setup_complete;
1447         gadget->ep0->driver_data = cdev;
1448
1449         cdev->bufsiz = USB_BUFSIZ;
1450         cdev->driver = composite;
1451
1452         /*
1453          * As per USB compliance update, a device that is actively drawing
1454          * more than 100mA from USB must report itself as bus-powered in
1455          * the GetStatus(DEVICE) call.
1456          */
1457         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1458                 usb_gadget_set_selfpowered(gadget);
1459
1460         /* interface and string IDs start at zero via kzalloc.
1461          * we force endpoints to start unassigned; few controller
1462          * drivers will zero ep->driver_data.
1463          */
1464         usb_ep_autoconfig_reset(cdev->gadget);
1465
1466         /* composite gadget needs to assign strings for whole device (like
1467          * serial number), register function drivers, potentially update
1468          * power state and consumption, etc
1469          */
1470         status = composite_gadget_bind(cdev);
1471         if (status < 0)
1472                 goto fail;
1473
1474         cdev->desc = *composite->dev;
1475
1476         /* standardized runtime overrides for device ID data */
1477         if (idVendor)
1478                 cdev->desc.idVendor = cpu_to_le16(idVendor);
1479         else
1480                 idVendor = le16_to_cpu(cdev->desc.idVendor);
1481         if (idProduct)
1482                 cdev->desc.idProduct = cpu_to_le16(idProduct);
1483         else
1484                 idProduct = le16_to_cpu(cdev->desc.idProduct);
1485         if (bcdDevice)
1486                 cdev->desc.bcdDevice = cpu_to_le16(bcdDevice);
1487         else
1488                 bcdDevice = le16_to_cpu(cdev->desc.bcdDevice);
1489
1490         /* string overrides */
1491         if (iManufacturer || !cdev->desc.iManufacturer) {
1492                 if (!iManufacturer && !composite->iManufacturer &&
1493                     !*composite_manufacturer)
1494                         snprintf(composite_manufacturer,
1495                                  sizeof composite_manufacturer,
1496                                  "%s %s with %s",
1497                                  init_utsname()->sysname,
1498                                  init_utsname()->release,
1499                                  gadget->name);
1500
1501                 cdev->manufacturer_override =
1502                         override_id(cdev, &cdev->desc.iManufacturer);
1503         }
1504
1505         if (iProduct || (!cdev->desc.iProduct && composite->iProduct))
1506                 cdev->product_override =
1507                         override_id(cdev, &cdev->desc.iProduct);
1508
1509         if (iSerialNumber ||
1510             (!cdev->desc.iSerialNumber && composite->iSerialNumber))
1511                 cdev->serial_override =
1512                         override_id(cdev, &cdev->desc.iSerialNumber);
1513
1514         /* has userspace failed to provide a serial number? */
1515         if (composite->needs_serial && !cdev->desc.iSerialNumber)
1516                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1517
1518         /* finish up */
1519         status = device_create_file(&gadget->dev, &dev_attr_suspended);
1520         if (status)
1521                 goto fail;
1522
1523         INFO(cdev, "%s ready\n", composite->name);
1524         return 0;
1525
1526 fail:
1527         composite_unbind(gadget);
1528         return status;
1529 }
1530
1531 /*-------------------------------------------------------------------------*/
1532
1533 static void
1534 composite_suspend(struct usb_gadget *gadget)
1535 {
1536         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1537         struct usb_function             *f;
1538
1539         /* REVISIT:  should we have config level
1540          * suspend/resume callbacks?
1541          */
1542         DBG(cdev, "suspend\n");
1543         if (cdev->config) {
1544                 list_for_each_entry(f, &cdev->config->functions, list) {
1545                         if (f->suspend)
1546                                 f->suspend(f);
1547                 }
1548         }
1549         if (composite->suspend)
1550                 composite->suspend(cdev);
1551
1552         cdev->suspended = 1;
1553
1554         usb_gadget_vbus_draw(gadget, 2);
1555 }
1556
1557 static void
1558 composite_resume(struct usb_gadget *gadget)
1559 {
1560         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1561         struct usb_function             *f;
1562         u8                              maxpower;
1563
1564         /* REVISIT:  should we have config level
1565          * suspend/resume callbacks?
1566          */
1567         DBG(cdev, "resume\n");
1568         if (composite->resume)
1569                 composite->resume(cdev);
1570         if (cdev->config) {
1571                 list_for_each_entry(f, &cdev->config->functions, list) {
1572                         if (f->resume)
1573                                 f->resume(f);
1574                 }
1575
1576                 maxpower = cdev->config->bMaxPower;
1577
1578                 usb_gadget_vbus_draw(gadget, maxpower ?
1579                         (2 * maxpower) : CONFIG_USB_GADGET_VBUS_DRAW);
1580         }
1581
1582         cdev->suspended = 0;
1583 }
1584
1585 /*-------------------------------------------------------------------------*/
1586
1587 static struct usb_gadget_driver composite_driver = {
1588 #ifdef CONFIG_USB_GADGET_SUPERSPEED
1589         .max_speed      = USB_SPEED_SUPER,
1590 #else
1591         .max_speed      = USB_SPEED_HIGH,
1592 #endif
1593
1594         .unbind         = composite_unbind,
1595
1596         .setup          = composite_setup,
1597         .disconnect     = composite_disconnect,
1598
1599         .suspend        = composite_suspend,
1600         .resume         = composite_resume,
1601
1602         .driver = {
1603                 .owner          = THIS_MODULE,
1604         },
1605 };
1606
1607 /**
1608  * usb_composite_probe() - register a composite driver
1609  * @driver: the driver to register
1610  * @bind: the callback used to allocate resources that are shared across the
1611  *      whole device, such as string IDs, and add its configurations using
1612  *      @usb_add_config().  This may fail by returning a negative errno
1613  *      value; it should return zero on successful initialization.
1614  * Context: single threaded during gadget setup
1615  *
1616  * This function is used to register drivers using the composite driver
1617  * framework.  The return value is zero, or a negative errno value.
1618  * Those values normally come from the driver's @bind method, which does
1619  * all the work of setting up the driver to match the hardware.
1620  *
1621  * On successful return, the gadget is ready to respond to requests from
1622  * the host, unless one of its components invokes usb_gadget_disconnect()
1623  * while it was binding.  That would usually be done in order to wait for
1624  * some userspace participation.
1625  */
1626 int usb_composite_probe(struct usb_composite_driver *driver,
1627                                int (*bind)(struct usb_composite_dev *cdev))
1628 {
1629         if (!driver || !driver->dev || !bind || composite)
1630                 return -EINVAL;
1631
1632         if (!driver->name)
1633                 driver->name = "composite";
1634         if (!driver->iProduct)
1635                 driver->iProduct = driver->name;
1636         composite_driver.function =  (char *) driver->name;
1637         composite_driver.driver.name = driver->name;
1638         composite_driver.max_speed =
1639                 min_t(u8, composite_driver.max_speed, driver->max_speed);
1640         composite = driver;
1641         composite_gadget_bind = bind;
1642
1643         return usb_gadget_probe_driver(&composite_driver, composite_bind);
1644 }
1645
1646 /**
1647  * usb_composite_unregister() - unregister a composite driver
1648  * @driver: the driver to unregister
1649  *
1650  * This function is used to unregister drivers using the composite
1651  * driver framework.
1652  */
1653 void usb_composite_unregister(struct usb_composite_driver *driver)
1654 {
1655         if (composite != driver)
1656                 return;
1657         usb_gadget_unregister_driver(&composite_driver);
1658 }
1659
1660 /**
1661  * usb_composite_setup_continue() - Continue with the control transfer
1662  * @cdev: the composite device who's control transfer was kept waiting
1663  *
1664  * This function must be called by the USB function driver to continue
1665  * with the control transfer's data/status stage in case it had requested to
1666  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1667  * can request the composite framework to delay the setup request's data/status
1668  * stages by returning USB_GADGET_DELAYED_STATUS.
1669  */
1670 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1671 {
1672         int                     value;
1673         struct usb_request      *req = cdev->req;
1674         unsigned long           flags;
1675
1676         DBG(cdev, "%s\n", __func__);
1677         spin_lock_irqsave(&cdev->lock, flags);
1678
1679         if (cdev->delayed_status == 0) {
1680                 WARN(cdev, "%s: Unexpected call\n", __func__);
1681
1682         } else if (--cdev->delayed_status == 0) {
1683                 DBG(cdev, "%s: Completing delayed status\n", __func__);
1684                 req->length = 0;
1685                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1686                 if (value < 0) {
1687                         DBG(cdev, "ep_queue --> %d\n", value);
1688                         req->status = 0;
1689                         composite_setup_complete(cdev->gadget->ep0, req);
1690                 }
1691         }
1692
1693         spin_unlock_irqrestore(&cdev->lock, flags);
1694 }
1695