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  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 /* #define VERBOSE_DEBUG */
  22
  23 #include <linux/kallsyms.h>
  24 #include <linux/kernel.h>
  25 #include <linux/slab.h>
  26 #include <linux/device.h>
  27 #include <linux/utsname.h>
  28
  29 #include <linux/usb/composite.h>
  30 #include <asm/unaligned.h>
  31
  32 /*
  33  * The code in this file is utility code, used to build a gadget driver
  34  * from one or more "function" drivers, one or more "configuration"
  35  * objects, and a "usb_composite_driver" by gluing them together along
  36  * with the relevant device-wide data.
  37  */
  38
  39 /* big enough to hold our biggest descriptor */
  40 #define USB_BUFSIZ      1024
  41
  42 static struct usb_composite_driver *composite;
  43 static int (*composite_gadget_bind)(struct usb_composite_dev *cdev);
  44
  45 /* Some systems will need runtime overrides for the  product identifiers
  46  * published in the device descriptor, either numbers or strings or both.
  47  * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
  48  */
  49
  50 static ushort idVendor;
  51 module_param(idVendor, ushort, 0);
  52 MODULE_PARM_DESC(idVendor, "USB Vendor ID");
  53
  54 static ushort idProduct;
  55 module_param(idProduct, ushort, 0);
  56 MODULE_PARM_DESC(idProduct, "USB Product ID");
  57
  58 static ushort bcdDevice;
  59 module_param(bcdDevice, ushort, 0);
  60 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");
  61
  62 static char *iManufacturer;
  63 module_param(iManufacturer, charp, 0);
  64 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");
  65
  66 static char *iProduct;
  67 module_param(iProduct, charp, 0);
  68 MODULE_PARM_DESC(iProduct, "USB Product string");
  69
  70 static char *iSerialNumber;
  71 module_param(iSerialNumber, charp, 0);
  72 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string");
  73
  74 static char composite_manufacturer[50];
  75
  76 /*-------------------------------------------------------------------------*/
  77 /**
  78  * next_ep_desc() - advance to the next EP descriptor
  79  * @t: currect pointer within descriptor array
  80  *
  81  * Return: next EP descriptor or NULL
  82  *
  83  * Iterate over @t until either EP descriptor found or
  84  * NULL (that indicates end of list) encountered
  85  */
  86 static struct usb_descriptor_header**
  87 next_ep_desc(struct usb_descriptor_header **t)
  88 {
  89         for (; *t; t++) {
  90                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
  91                         return t;
  92         }
  93         return NULL;
  94 }
  95
  96 /*
  97  * for_each_ep_desc()- iterate over endpoint descriptors in the
  98  *              descriptors list
  99  * @start:      pointer within descriptor array.
 100  * @ep_desc:    endpoint descriptor to use as the loop cursor
 101  */
 102 #define for_each_ep_desc(start, ep_desc) \
 103         for (ep_desc = next_ep_desc(start); \
 104               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
 105
 106 /**
 107  * config_ep_by_speed() - configures the given endpoint
 108  * according to gadget speed.
 109  * @g: pointer to the gadget
 110  * @f: usb function
 111  * @_ep: the endpoint to configure
 112  *
 113  * Return: error code, 0 on success
 114  *
 115  * This function chooses the right descriptors for a given
 116  * endpoint according to gadget speed and saves it in the
 117  * endpoint desc field. If the endpoint already has a descriptor
 118  * assigned to it - overwrites it with currently corresponding
 119  * descriptor. The endpoint maxpacket field is updated according
 120  * to the chosen descriptor.
 121  * Note: the supplied function should hold all the descriptors
 122  * for supported speeds
 123  */
 124 int config_ep_by_speed(struct usb_gadget *g,
 125                         struct usb_function *f,
 126                         struct usb_ep *_ep)
 127 {
 128         struct usb_endpoint_descriptor *chosen_desc = NULL;
 129         struct usb_descriptor_header **speed_desc = NULL;
 130
 131         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 132         int want_comp_desc = 0;
 133
 134         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 135
 136         if (!g || !f || !_ep)
 137                 return -EIO;
 138
 139         /* select desired speed */
 140         switch (g->speed) {
 141         case USB_SPEED_SUPER:
 142                 if (gadget_is_superspeed(g)) {
 143                         speed_desc = f->ss_descriptors;
 144                         want_comp_desc = 1;
 145                         break;
 146                 }
 147                 /* else: Fall trough */
 148         case USB_SPEED_HIGH:
 149                 if (gadget_is_dualspeed(g)) {
 150                         speed_desc = f->hs_descriptors;
 151                         break;
 152                 }
 153                 /* else: fall through */
 154         default:
 155                 speed_desc = f->descriptors;
 156         }
 157         /* find descriptors */
 158         for_each_ep_desc(speed_desc, d_spd) {
 159                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 160                 if (chosen_desc->bEndpointAddress == _ep->address)
 161                         goto ep_found;
 162         }
 163         return -EIO;
 164
 165 ep_found:
 166         /* commit results */
 167         _ep->maxpacket = le16_to_cpu(chosen_desc->wMaxPacketSize);
 168         _ep->desc = chosen_desc;
 169         _ep->comp_desc = NULL;
 170         _ep->maxburst = 0;
 171         _ep->mult = 0;
 172         if (!want_comp_desc)
 173                 return 0;
 174
 175         /*
 176          * Companion descriptor should follow EP descriptor
 177          * USB 3.0 spec, #9.6.7
 178          */
 179         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 180         if (!comp_desc ||
 181             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 182                 return -EIO;
 183         _ep->comp_desc = comp_desc;
 184         if (g->speed == USB_SPEED_SUPER) {
 185                 switch (usb_endpoint_type(_ep->desc)) {
 186                 case USB_ENDPOINT_XFER_BULK:
 187                 case USB_ENDPOINT_XFER_INT:
 188                         _ep->maxburst = comp_desc->bMaxBurst;
 189                         break;
 190                 case USB_ENDPOINT_XFER_ISOC:
 191                         /* mult: bits 1:0 of bmAttributes */
 192                         _ep->mult = comp_desc->bmAttributes & 0x3;
 193                         break;
 194                 default:
 195                         /* Do nothing for control endpoints */
 196                         break;
 197                 }
 198         }
 199         return 0;
 200 }
 201
 202 /**
 203  * usb_add_function() - add a function to a configuration
 204  * @config: the configuration
 205  * @function: the function being added
 206  * Context: single threaded during gadget setup
 207  *
 208  * After initialization, each configuration must have one or more
 209  * functions added to it.  Adding a function involves calling its @bind()
 210  * method to allocate resources such as interface and string identifiers
 211  * and endpoints.
 212  *
 213  * This function returns the value of the function's bind(), which is
 214  * zero for success else a negative errno value.
 215  */
 216 int usb_add_function(struct usb_configuration *config,
 217                 struct usb_function *function)
 218 {
 219         int     value = -EINVAL;
 220
 221         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 222                         function->name, function,
 223                         config->label, config);
 224
 225         if (!function->set_alt || !function->disable)
 226                 goto done;
 227
 228         function->config = config;
 229         list_add_tail(&function->list, &config->functions);
 230
 231         /* REVISIT *require* function->bind? */
 232         if (function->bind) {
 233                 value = function->bind(config, function);
 234                 if (value < 0) {
 235                         list_del(&function->list);
 236                         function->config = NULL;
 237                 }
 238         } else
 239                 value = 0;
 240
 241         /* We allow configurations that don't work at both speeds.
 242          * If we run into a lowspeed Linux system, treat it the same
 243          * as full speed ... it's the function drivers that will need
 244          * to avoid bulk and ISO transfers.
 245          */
 246         if (!config->fullspeed && function->descriptors)
 247                 config->fullspeed = true;
 248         if (!config->highspeed && function->hs_descriptors)
 249                 config->highspeed = true;
 250         if (!config->superspeed && function->ss_descriptors)
 251                 config->superspeed = true;
 252
 253 done:
 254         if (value)
 255                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 256                                 function->name, function, value);
 257         return value;
 258 }
 259
 260 /**
 261  * usb_function_deactivate - prevent function and gadget enumeration
 262  * @function: the function that isn't yet ready to respond
 263  *
 264  * Blocks response of the gadget driver to host enumeration by
 265  * preventing the data line pullup from being activated.  This is
 266  * normally called during @bind() processing to change from the
 267  * initial "ready to respond" state, or when a required resource
 268  * becomes available.
 269  *
 270  * For example, drivers that serve as a passthrough to a userspace
 271  * daemon can block enumeration unless that daemon (such as an OBEX,
 272  * MTP, or print server) is ready to handle host requests.
 273  *
 274  * Not all systems support software control of their USB peripheral
 275  * data pullups.
 276  *
 277  * Returns zero on success, else negative errno.
 278  */
 279 int usb_function_deactivate(struct usb_function *function)
 280 {
 281         struct usb_composite_dev        *cdev = function->config->cdev;
 282         unsigned long                   flags;
 283         int                             status = 0;
 284
 285         spin_lock_irqsave(&cdev->lock, flags);
 286
 287         if (cdev->deactivations == 0)
 288                 status = usb_gadget_disconnect(cdev->gadget);
 289         if (status == 0)
 290                 cdev->deactivations++;
 291
 292         spin_unlock_irqrestore(&cdev->lock, flags);
 293         return status;
 294 }
 295
 296 /**
 297  * usb_function_activate - allow function and gadget enumeration
 298  * @function: function on which usb_function_activate() was called
 299  *
 300  * Reverses effect of usb_function_deactivate().  If no more functions
 301  * are delaying their activation, the gadget driver will respond to
 302  * host enumeration procedures.
 303  *
 304  * Returns zero on success, else negative errno.
 305  */
 306 int usb_function_activate(struct usb_function *function)
 307 {
 308         struct usb_composite_dev        *cdev = function->config->cdev;
 309         int                             status = 0;
 310
 311         spin_lock(&cdev->lock);
 312
 313         if (WARN_ON(cdev->deactivations == 0))
 314                 status = -EINVAL;
 315         else {
 316                 cdev->deactivations--;
 317                 if (cdev->deactivations == 0)
 318                         status = usb_gadget_connect(cdev->gadget);
 319         }
 320
 321         spin_unlock(&cdev->lock);
 322         return status;
 323 }
 324
 325 /**
 326  * usb_interface_id() - allocate an unused interface ID
 327  * @config: configuration associated with the interface
 328  * @function: function handling the interface
 329  * Context: single threaded during gadget setup
 330  *
 331  * usb_interface_id() is called from usb_function.bind() callbacks to
 332  * allocate new interface IDs.  The function driver will then store that
 333  * ID in interface, association, CDC union, and other descriptors.  It
 334  * will also handle any control requests targeted at that interface,
 335  * particularly changing its altsetting via set_alt().  There may
 336  * also be class-specific or vendor-specific requests to handle.
 337  *
 338  * All interface identifier should be allocated using this routine, to
 339  * ensure that for example different functions don't wrongly assign
 340  * different meanings to the same identifier.  Note that since interface
 341  * identifiers are configuration-specific, functions used in more than
 342  * one configuration (or more than once in a given configuration) need
 343  * multiple versions of the relevant descriptors.
 344  *
 345  * Returns the interface ID which was allocated; or -ENODEV if no
 346  * more interface IDs can be allocated.
 347  */
 348 int usb_interface_id(struct usb_configuration *config,
 349                 struct usb_function *function)
 350 {
 351         unsigned id = config->next_interface_id;
 352
 353         if (id < MAX_CONFIG_INTERFACES) {
 354                 config->interface[id] = function;
 355                 config->next_interface_id = id + 1;
 356                 return id;
 357         }
 358         return -ENODEV;
 359 }
 360
 361 static int config_buf(struct usb_configuration *config,
 362                 enum usb_device_speed speed, void *buf, u8 type)
 363 {
 364         struct usb_config_descriptor    *c = buf;
 365         void                            *next = buf + USB_DT_CONFIG_SIZE;
 366         int                             len = USB_BUFSIZ - USB_DT_CONFIG_SIZE;
 367         struct usb_function             *f;
 368         int                             status;
 369
 370         /* write the config descriptor */
 371         c = buf;
 372         c->bLength = USB_DT_CONFIG_SIZE;
 373         c->bDescriptorType = type;
 374         /* wTotalLength is written later */
 375         c->bNumInterfaces = config->next_interface_id;
 376         c->bConfigurationValue = config->bConfigurationValue;
 377         c->iConfiguration = config->iConfiguration;
 378         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 379         c->bMaxPower = config->bMaxPower ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
 380
 381         /* There may be e.g. OTG descriptors */
 382         if (config->descriptors) {
 383                 status = usb_descriptor_fillbuf(next, len,
 384                                 config->descriptors);
 385                 if (status < 0)
 386                         return status;
 387                 len -= status;
 388                 next += status;
 389         }
 390
 391         /* add each function's descriptors */
 392         list_for_each_entry(f, &config->functions, list) {
 393                 struct usb_descriptor_header **descriptors;
 394
 395                 switch (speed) {
 396                 case USB_SPEED_SUPER:
 397                         descriptors = f->ss_descriptors;
 398                         break;
 399                 case USB_SPEED_HIGH:
 400                         descriptors = f->hs_descriptors;
 401                         break;
 402                 default:
 403                         descriptors = f->descriptors;
 404                 }
 405
 406                 if (!descriptors)
 407                         continue;
 408                 status = usb_descriptor_fillbuf(next, len,
 409                         (const struct usb_descriptor_header **) descriptors);
 410                 if (status < 0)
 411                         return status;
 412                 len -= status;
 413                 next += status;
 414         }
 415
 416         len = next - buf;
 417         c->wTotalLength = cpu_to_le16(len);
 418         return len;
 419 }
 420
 421 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 422 {
 423         struct usb_gadget               *gadget = cdev->gadget;
 424         struct usb_configuration        *c;
 425         u8                              type = w_value >> 8;
 426         enum usb_device_speed           speed = USB_SPEED_UNKNOWN;
 427
 428         if (gadget->speed == USB_SPEED_SUPER)
 429                 speed = gadget->speed;
 430         else if (gadget_is_dualspeed(gadget)) {
 431                 int     hs = 0;
 432                 if (gadget->speed == USB_SPEED_HIGH)
 433                         hs = 1;
 434                 if (type == USB_DT_OTHER_SPEED_CONFIG)
 435                         hs = !hs;
 436                 if (hs)
 437                         speed = USB_SPEED_HIGH;
 438
 439         }
 440
 441         /* This is a lookup by config *INDEX* */
 442         w_value &= 0xff;
 443         list_for_each_entry(c, &cdev->configs, list) {
 444                 /* ignore configs that won't work at this speed */
 445                 switch (speed) {
 446                 case USB_SPEED_SUPER:
 447                         if (!c->superspeed)
 448                                 continue;
 449                         break;
 450                 case USB_SPEED_HIGH:
 451                         if (!c->highspeed)
 452                                 continue;
 453                         break;
 454                 default:
 455                         if (!c->fullspeed)
 456                                 continue;
 457                 }
 458
 459                 if (w_value == 0)
 460                         return config_buf(c, speed, cdev->req->buf, type);
 461                 w_value--;
 462         }
 463         return -EINVAL;
 464 }
 465
 466 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 467 {
 468         struct usb_gadget               *gadget = cdev->gadget;
 469         struct usb_configuration        *c;
 470         unsigned                        count = 0;
 471         int                             hs = 0;
 472         int                             ss = 0;
 473
 474         if (gadget_is_dualspeed(gadget)) {
 475                 if (gadget->speed == USB_SPEED_HIGH)
 476                         hs = 1;
 477                 if (gadget->speed == USB_SPEED_SUPER)
 478                         ss = 1;
 479                 if (type == USB_DT_DEVICE_QUALIFIER)
 480                         hs = !hs;
 481         }
 482         list_for_each_entry(c, &cdev->configs, list) {
 483                 /* ignore configs that won't work at this speed */
 484                 if (ss) {
 485                         if (!c->superspeed)
 486                                 continue;
 487                 } else if (hs) {
 488                         if (!c->highspeed)
 489                                 continue;
 490                 } else {
 491                         if (!c->fullspeed)
 492                                 continue;
 493                 }
 494                 count++;
 495         }
 496         return count;
 497 }
 498
 499 /**
 500  * bos_desc() - prepares the BOS descriptor.
 501  * @cdev: pointer to usb_composite device to generate the bos
 502  *      descriptor for
 503  *
 504  * This function generates the BOS (Binary Device Object)
 505  * descriptor and its device capabilities descriptors. The BOS
 506  * descriptor should be supported by a SuperSpeed device.
 507  */
 508 static int bos_desc(struct usb_composite_dev *cdev)
 509 {
 510         struct usb_ext_cap_descriptor   *usb_ext;
 511         struct usb_ss_cap_descriptor    *ss_cap;
 512         struct usb_dcd_config_params    dcd_config_params;
 513         struct usb_bos_descriptor       *bos = cdev->req->buf;
 514
 515         bos->bLength = USB_DT_BOS_SIZE;
 516         bos->bDescriptorType = USB_DT_BOS;
 517
 518         bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 519         bos->bNumDeviceCaps = 0;
 520
 521         /*
 522          * A SuperSpeed device shall include the USB2.0 extension descriptor
 523          * and shall support LPM when operating in USB2.0 HS mode.
 524          */
 525         usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 526         bos->bNumDeviceCaps++;
 527         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 528         usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 529         usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 530         usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 531         usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
 532
 533         /*
 534          * The Superspeed USB Capability descriptor shall be implemented by all
 535          * SuperSpeed devices.
 536          */
 537         ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 538         bos->bNumDeviceCaps++;
 539         le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 540         ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 541         ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 542         ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 543         ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 544         ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 545                                 USB_FULL_SPEED_OPERATION |
 546                                 USB_HIGH_SPEED_OPERATION |
 547                                 USB_5GBPS_OPERATION);
 548         ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 549
 550         /* Get Controller configuration */
 551         if (cdev->gadget->ops->get_config_params)
 552                 cdev->gadget->ops->get_config_params(&dcd_config_params);
 553         else {
 554                 dcd_config_params.bU1devExitLat = USB_DEFULT_U1_DEV_EXIT_LAT;
 555                 dcd_config_params.bU2DevExitLat =
 556                         cpu_to_le16(USB_DEFULT_U2_DEV_EXIT_LAT);
 557         }
 558         ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 559         ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 560
 561         return le16_to_cpu(bos->wTotalLength);
 562 }
 563
 564 static void device_qual(struct usb_composite_dev *cdev)
 565 {
 566         struct usb_qualifier_descriptor *qual = cdev->req->buf;
 567
 568         qual->bLength = sizeof(*qual);
 569         qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 570         /* POLICY: same bcdUSB and device type info at both speeds */
 571         qual->bcdUSB = cdev->desc.bcdUSB;
 572         qual->bDeviceClass = cdev->desc.bDeviceClass;
 573         qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 574         qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 575         /* ASSUME same EP0 fifo size at both speeds */
 576         qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 577         qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 578         qual->bRESERVED = 0;
 579 }
 580
 581 /*-------------------------------------------------------------------------*/
 582
 583 static void reset_config(struct usb_composite_dev *cdev)
 584 {
 585         struct usb_function             *f;
 586
 587         DBG(cdev, "reset config\n");
 588
 589         list_for_each_entry(f, &cdev->config->functions, list) {
 590                 if (f->disable)
 591                         f->disable(f);
 592
 593                 bitmap_zero(f->endpoints, 32);
 594         }
 595         cdev->config = NULL;
 596 }
 597
 598 static int set_config(struct usb_composite_dev *cdev,
 599                 const struct usb_ctrlrequest *ctrl, unsigned number)
 600 {
 601         struct usb_gadget       *gadget = cdev->gadget;
 602         struct usb_configuration *c = NULL;
 603         int                     result = -EINVAL;
 604         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 605         int                     tmp;
 606
 607         if (number) {
 608                 list_for_each_entry(c, &cdev->configs, list) {
 609                         if (c->bConfigurationValue == number) {
 610                                 /*
 611                                  * We disable the FDs of the previous
 612                                  * configuration only if the new configuration
 613                                  * is a valid one
 614                                  */
 615                                 if (cdev->config)
 616                                         reset_config(cdev);
 617                                 result = 0;
 618                                 break;
 619                         }
 620                 }
 621                 if (result < 0)
 622                         goto done;
 623         } else { /* Zero configuration value - need to reset the config */
 624                 if (cdev->config)
 625                         reset_config(cdev);
 626                 result = 0;
 627         }
 628
 629         INFO(cdev, "%s speed config #%d: %s\n",
 630                 ({ char *speed;
 631                 switch (gadget->speed) {
 632                 case USB_SPEED_LOW:
 633                         speed = "low";
 634                         break;
 635                 case USB_SPEED_FULL:
 636                         speed = "full";
 637                         break;
 638                 case USB_SPEED_HIGH:
 639                         speed = "high";
 640                         break;
 641                 case USB_SPEED_SUPER:
 642                         speed = "super";
 643                         break;
 644                 default:
 645                         speed = "?";
 646                         break;
 647                 } ; speed; }), number, c ? c->label : "unconfigured");
 648
 649         if (!c)
 650                 goto done;
 651
 652         cdev->config = c;
 653
 654         /* Initialize all interfaces by setting them to altsetting zero. */
 655         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 656                 struct usb_function     *f = c->interface[tmp];
 657                 struct usb_descriptor_header **descriptors;
 658
 659                 if (!f)
 660                         break;
 661
 662                 /*
 663                  * Record which endpoints are used by the function. This is used
 664                  * to dispatch control requests targeted at that endpoint to the
 665                  * function's setup callback instead of the current
 666                  * configuration's setup callback.
 667                  */
 668                 switch (gadget->speed) {
 669                 case USB_SPEED_SUPER:
 670                         descriptors = f->ss_descriptors;
 671                         break;
 672                 case USB_SPEED_HIGH:
 673                         descriptors = f->hs_descriptors;
 674                         break;
 675                 default:
 676                         descriptors = f->descriptors;
 677                 }
 678
 679                 for (; *descriptors; ++descriptors) {
 680                         struct usb_endpoint_descriptor *ep;
 681                         int addr;
 682
 683                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 684                                 continue;
 685
 686                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 687                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 688                              |  (ep->bEndpointAddress & 0x0f);
 689                         set_bit(addr, f->endpoints);
 690                 }
 691
 692                 result = f->set_alt(f, tmp, 0);
 693                 if (result < 0) {
 694                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 695                                         tmp, f->name, f, result);
 696
 697                         reset_config(cdev);
 698                         goto done;
 699                 }
 700
 701                 if (result == USB_GADGET_DELAYED_STATUS) {
 702                         DBG(cdev,
 703                          "%s: interface %d (%s) requested delayed status\n",
 704                                         __func__, tmp, f->name);
 705                         cdev->delayed_status++;
 706                         DBG(cdev, "delayed_status count %d\n",
 707                                         cdev->delayed_status);
 708                 }
 709         }
 710
 711         /* when we return, be sure our power usage is valid */
 712         power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
 713 done:
 714         usb_gadget_vbus_draw(gadget, power);
 715         if (result >= 0 && cdev->delayed_status)
 716                 result = USB_GADGET_DELAYED_STATUS;
 717         return result;
 718 }
 719
 720 /**
 721  * usb_add_config() - add a configuration to a device.
 722  * @cdev: wraps the USB gadget
 723  * @config: the configuration, with bConfigurationValue assigned
 724  * @bind: the configuration's bind function
 725  * Context: single threaded during gadget setup
 726  *
 727  * One of the main tasks of a composite @bind() routine is to
 728  * add each of the configurations it supports, using this routine.
 729  *
 730  * This function returns the value of the configuration's @bind(), which
 731  * is zero for success else a negative errno value.  Binding configurations
 732  * assigns global resources including string IDs, and per-configuration
 733  * resources such as interface IDs and endpoints.
 734  */
 735 int usb_add_config(struct usb_composite_dev *cdev,
 736                 struct usb_configuration *config,
 737                 int (*bind)(struct usb_configuration *))
 738 {
 739         int                             status = -EINVAL;
 740         struct usb_configuration        *c;
 741
 742         DBG(cdev, "adding config #%u '%s'/%p\n",
 743                         config->bConfigurationValue,
 744                         config->label, config);
 745
 746         if (!config->bConfigurationValue || !bind)
 747                 goto done;
 748
 749         /* Prevent duplicate configuration identifiers */
 750         list_for_each_entry(c, &cdev->configs, list) {
 751                 if (c->bConfigurationValue == config->bConfigurationValue) {
 752                         status = -EBUSY;
 753                         goto done;
 754                 }
 755         }
 756
 757         config->cdev = cdev;
 758         list_add_tail(&config->list, &cdev->configs);
 759
 760         INIT_LIST_HEAD(&config->functions);
 761         config->next_interface_id = 0;
 762
 763         status = bind(config);
 764         if (status < 0) {
 765                 list_del(&config->list);
 766                 config->cdev = NULL;
 767         } else {
 768                 unsigned        i;
 769
 770                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 771                         config->bConfigurationValue, config,
 772                         config->superspeed ? " super" : "",
 773                         config->highspeed ? " high" : "",
 774                         config->fullspeed
 775                                 ? (gadget_is_dualspeed(cdev->gadget)
 776                                         ? " full"
 777                                         : " full/low")
 778                                 : "");
 779
 780                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 781                         struct usb_function     *f = config->interface[i];
 782
 783                         if (!f)
 784                                 continue;
 785                         DBG(cdev, "  interface %d = %s/%p\n",
 786                                 i, f->name, f);
 787                 }
 788         }
 789
 790         /* set_alt(), or next bind(), sets up
 791          * ep->driver_data as needed.
 792          */
 793         usb_ep_autoconfig_reset(cdev->gadget);
 794
 795 done:
 796         if (status)
 797                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 798                                 config->bConfigurationValue, status);
 799         return status;
 800 }
 801
 802 /*-------------------------------------------------------------------------*/
 803
 804 /* We support strings in multiple languages ... string descriptor zero
 805  * says which languages are supported.  The typical case will be that
 806  * only one language (probably English) is used, with I18N handled on
 807  * the host side.
 808  */
 809
 810 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 811 {
 812         const struct usb_gadget_strings *s;
 813         u16                             language;
 814         __le16                          *tmp;
 815
 816         while (*sp) {
 817                 s = *sp;
 818                 language = cpu_to_le16(s->language);
 819                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 820                         if (*tmp == language)
 821                                 goto repeat;
 822                 }
 823                 *tmp++ = language;
 824 repeat:
 825                 sp++;
 826         }
 827 }
 828
 829 static int lookup_string(
 830         struct usb_gadget_strings       **sp,
 831         void                            *buf,
 832         u16                             language,
 833         int                             id
 834 )
 835 {
 836         struct usb_gadget_strings       *s;
 837         int                             value;
 838
 839         while (*sp) {
 840                 s = *sp++;
 841                 if (s->language != language)
 842                         continue;
 843                 value = usb_gadget_get_string(s, id, buf);
 844                 if (value > 0)
 845                         return value;
 846         }
 847         return -EINVAL;
 848 }
 849
 850 static int get_string(struct usb_composite_dev *cdev,
 851                 void *buf, u16 language, int id)
 852 {
 853         struct usb_configuration        *c;
 854         struct usb_function             *f;
 855         int                             len;
 856         const char                      *str;
 857
 858         /* Yes, not only is USB's I18N support probably more than most
 859          * folk will ever care about ... also, it's all supported here.
 860          * (Except for UTF8 support for Unicode's "Astral Planes".)
 861          */
 862
 863         /* 0 == report all available language codes */
 864         if (id == 0) {
 865                 struct usb_string_descriptor    *s = buf;
 866                 struct usb_gadget_strings       **sp;
 867
 868                 memset(s, 0, 256);
 869                 s->bDescriptorType = USB_DT_STRING;
 870
 871                 sp = composite->strings;
 872                 if (sp)
 873                         collect_langs(sp, s->wData);
 874
 875                 list_for_each_entry(c, &cdev->configs, list) {
 876                         sp = c->strings;
 877                         if (sp)
 878                                 collect_langs(sp, s->wData);
 879
 880                         list_for_each_entry(f, &c->functions, list) {
 881                                 sp = f->strings;
 882                                 if (sp)
 883                                         collect_langs(sp, s->wData);
 884                         }
 885                 }
 886
 887                 for (len = 0; len <= 126 && s->wData[len]; len++)
 888                         continue;
 889                 if (!len)
 890                         return -EINVAL;
 891
 892                 s->bLength = 2 * (len + 1);
 893                 return s->bLength;
 894         }
 895
 896         /* Otherwise, look up and return a specified string.  First
 897          * check if the string has not been overridden.
 898          */
 899         if (cdev->manufacturer_override == id)
 900                 str = iManufacturer ?: composite->iManufacturer ?:
 901                         composite_manufacturer;
 902         else if (cdev->product_override == id)
 903                 str = iProduct ?: composite->iProduct;
 904         else if (cdev->serial_override == id)
 905                 str = iSerialNumber;
 906         else
 907                 str = NULL;
 908         if (str) {
 909                 struct usb_gadget_strings strings = {
 910                         .language = language,
 911                         .strings  = &(struct usb_string) { 0xff, str }
 912                 };
 913                 return usb_gadget_get_string(&strings, 0xff, buf);
 914         }
 915
 916         /* String IDs are device-scoped, so we look up each string
 917          * table we're told about.  These lookups are infrequent;
 918          * simpler-is-better here.
 919          */
 920         if (composite->strings) {
 921                 len = lookup_string(composite->strings, buf, language, id);
 922                 if (len > 0)
 923                         return len;
 924         }
 925         list_for_each_entry(c, &cdev->configs, list) {
 926                 if (c->strings) {
 927                         len = lookup_string(c->strings, buf, language, id);
 928                         if (len > 0)
 929                                 return len;
 930                 }
 931                 list_for_each_entry(f, &c->functions, list) {
 932                         if (!f->strings)
 933                                 continue;
 934                         len = lookup_string(f->strings, buf, language, id);
 935                         if (len > 0)
 936                                 return len;
 937                 }
 938         }
 939         return -EINVAL;
 940 }
 941
 942 /**
 943  * usb_string_id() - allocate an unused string ID
 944  * @cdev: the device whose string descriptor IDs are being allocated
 945  * Context: single threaded during gadget setup
 946  *
 947  * @usb_string_id() is called from bind() callbacks to allocate
 948  * string IDs.  Drivers for functions, configurations, or gadgets will
 949  * then store that ID in the appropriate descriptors and string table.
 950  *
 951  * All string identifier should be allocated using this,
 952  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
 953  * that for example different functions don't wrongly assign different
 954  * meanings to the same identifier.
 955  */
 956 int usb_string_id(struct usb_composite_dev *cdev)
 957 {
 958         if (cdev->next_string_id < 254) {
 959                 /* string id 0 is reserved by USB spec for list of
 960                  * supported languages */
 961                 /* 255 reserved as well? -- mina86 */
 962                 cdev->next_string_id++;
 963                 return cdev->next_string_id;
 964         }
 965         return -ENODEV;
 966 }
 967
 968 /**
 969  * usb_string_ids() - allocate unused string IDs in batch
 970  * @cdev: the device whose string descriptor IDs are being allocated
 971  * @str: an array of usb_string objects to assign numbers to
 972  * Context: single threaded during gadget setup
 973  *
 974  * @usb_string_ids() is called from bind() callbacks to allocate
 975  * string IDs.  Drivers for functions, configurations, or gadgets will
 976  * then copy IDs from the string table to the appropriate descriptors
 977  * and string table for other languages.
 978  *
 979  * All string identifier should be allocated using this,
 980  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
 981  * example different functions don't wrongly assign different meanings
 982  * to the same identifier.
 983  */
 984 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
 985 {
 986         int next = cdev->next_string_id;
 987
 988         for (; str->s; ++str) {
 989                 if (unlikely(next >= 254))
 990                         return -ENODEV;
 991                 str->id = ++next;
 992         }
 993
 994         cdev->next_string_id = next;
 995
 996         return 0;
 997 }
 998
 999 /**
1000  * usb_string_ids_n() - allocate unused string IDs in batch
1001  * @c: the device whose string descriptor IDs are being allocated
1002  * @n: number of string IDs to allocate
1003  * Context: single threaded during gadget setup
1004  *
1005  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1006  * valid IDs.  At least provided that @n is non-zero because if it
1007  * is, returns last requested ID which is now very useful information.
1008  *
1009  * @usb_string_ids_n() is called from bind() callbacks to allocate
1010  * string IDs.  Drivers for functions, configurations, or gadgets will
1011  * then store that ID in the appropriate descriptors and string table.
1012  *
1013  * All string identifier should be allocated using this,
1014  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1015  * example different functions don't wrongly assign different meanings
1016  * to the same identifier.
1017  */
1018 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1019 {
1020         unsigned next = c->next_string_id;
1021         if (unlikely(n > 254 || (unsigned)next + n > 254))
1022                 return -ENODEV;
1023         c->next_string_id += n;
1024         return next + 1;
1025 }
1026
1027
1028 /*-------------------------------------------------------------------------*/
1029
1030 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1031 {
1032         if (req->status || req->actual != req->length)
1033                 DBG((struct usb_composite_dev *) ep->driver_data,
1034                                 "setup complete --> %d, %d/%d\n",
1035                                 req->status, req->actual, req->length);
1036 }
1037
1038 /*
1039  * The setup() callback implements all the ep0 functionality that's
1040  * not handled lower down, in hardware or the hardware driver(like
1041  * device and endpoint feature flags, and their status).  It's all
1042  * housekeeping for the gadget function we're implementing.  Most of
1043  * the work is in config and function specific setup.
1044  */
1045 static int
1046 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1047 {
1048         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1049         struct usb_request              *req = cdev->req;
1050         int                             value = -EOPNOTSUPP;
1051         int                             status = 0;
1052         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1053         u8                              intf = w_index & 0xFF;
1054         u16                             w_value = le16_to_cpu(ctrl->wValue);
1055         u16                             w_length = le16_to_cpu(ctrl->wLength);
1056         struct usb_function             *f = NULL;
1057         u8                              endp;
1058
1059         /* partial re-init of the response message; the function or the
1060          * gadget might need to intercept e.g. a control-OUT completion
1061          * when we delegate to it.
1062          */
1063         req->zero = 0;
1064         req->complete = composite_setup_complete;
1065         req->length = 0;
1066         gadget->ep0->driver_data = cdev;
1067
1068         switch (ctrl->bRequest) {
1069
1070         /* we handle all standard USB descriptors */
1071         case USB_REQ_GET_DESCRIPTOR:
1072                 if (ctrl->bRequestType != USB_DIR_IN)
1073                         goto unknown;
1074                 switch (w_value >> 8) {
1075
1076                 case USB_DT_DEVICE:
1077                         cdev->desc.bNumConfigurations =
1078                                 count_configs(cdev, USB_DT_DEVICE);
1079                         cdev->desc.bMaxPacketSize0 =
1080                                 cdev->gadget->ep0->maxpacket;
1081                         if (gadget_is_superspeed(gadget)) {
1082                                 if (gadget->speed >= USB_SPEED_SUPER)
1083                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1084                                 else
1085                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1086                         }
1087
1088                         value = min(w_length, (u16) sizeof cdev->desc);
1089                         memcpy(req->buf, &cdev->desc, value);
1090                         break;
1091                 case USB_DT_DEVICE_QUALIFIER:
1092                         if (!gadget_is_dualspeed(gadget) ||
1093                             gadget->speed >= USB_SPEED_SUPER)
1094                                 break;
1095                         device_qual(cdev);
1096                         value = min_t(int, w_length,
1097                                 sizeof(struct usb_qualifier_descriptor));
1098                         break;
1099                 case USB_DT_OTHER_SPEED_CONFIG:
1100                         if (!gadget_is_dualspeed(gadget) ||
1101                             gadget->speed >= USB_SPEED_SUPER)
1102                                 break;
1103                         /* FALLTHROUGH */
1104                 case USB_DT_CONFIG:
1105                         value = config_desc(cdev, w_value);
1106                         if (value >= 0)
1107                                 value = min(w_length, (u16) value);
1108                         break;
1109                 case USB_DT_STRING:
1110                         value = get_string(cdev, req->buf,
1111                                         w_index, w_value & 0xff);
1112                         if (value >= 0)
1113                                 value = min(w_length, (u16) value);
1114                         break;
1115                 case USB_DT_BOS:
1116                         if (gadget_is_superspeed(gadget)) {
1117                                 value = bos_desc(cdev);
1118                                 value = min(w_length, (u16) value);
1119                         }
1120                         break;
1121                 }
1122                 break;
1123
1124         /* any number of configs can work */
1125         case USB_REQ_SET_CONFIGURATION:
1126                 if (ctrl->bRequestType != 0)
1127                         goto unknown;
1128                 if (gadget_is_otg(gadget)) {
1129                         if (gadget->a_hnp_support)
1130                                 DBG(cdev, "HNP available\n");
1131                         else if (gadget->a_alt_hnp_support)
1132                                 DBG(cdev, "HNP on another port\n");
1133                         else
1134                                 VDBG(cdev, "HNP inactive\n");
1135                 }
1136                 spin_lock(&cdev->lock);
1137                 value = set_config(cdev, ctrl, w_value);
1138                 spin_unlock(&cdev->lock);
1139                 break;
1140         case USB_REQ_GET_CONFIGURATION:
1141                 if (ctrl->bRequestType != USB_DIR_IN)
1142                         goto unknown;
1143                 if (cdev->config)
1144                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1145                 else
1146                         *(u8 *)req->buf = 0;
1147                 value = min(w_length, (u16) 1);
1148                 break;
1149
1150         /* function drivers must handle get/set altsetting; if there's
1151          * no get() method, we know only altsetting zero works.
1152          */
1153         case USB_REQ_SET_INTERFACE:
1154                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1155                         goto unknown;
1156                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1157                         break;
1158                 f = cdev->config->interface[intf];
1159                 if (!f)
1160                         break;
1161                 if (w_value && !f->set_alt)
1162                         break;
1163                 value = f->set_alt(f, w_index, w_value);
1164                 if (value == USB_GADGET_DELAYED_STATUS) {
1165                         DBG(cdev,
1166                          "%s: interface %d (%s) requested delayed status\n",
1167                                         __func__, intf, f->name);
1168                         cdev->delayed_status++;
1169                         DBG(cdev, "delayed_status count %d\n",
1170                                         cdev->delayed_status);
1171                 }
1172                 break;
1173         case USB_REQ_GET_INTERFACE:
1174                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1175                         goto unknown;
1176                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1177                         break;
1178                 f = cdev->config->interface[intf];
1179                 if (!f)
1180                         break;
1181                 /* lots of interfaces only need altsetting zero... */
1182                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1183                 if (value < 0)
1184                         break;
1185                 *((u8 *)req->buf) = value;
1186                 value = min(w_length, (u16) 1);
1187                 break;
1188
1189         /*
1190          * USB 3.0 additions:
1191          * Function driver should handle get_status request. If such cb
1192          * wasn't supplied we respond with default value = 0
1193          * Note: function driver should supply such cb only for the first
1194          * interface of the function
1195          */
1196         case USB_REQ_GET_STATUS:
1197                 if (!gadget_is_superspeed(gadget))
1198                         goto unknown;
1199                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1200                         goto unknown;
1201                 value = 2;      /* This is the length of the get_status reply */
1202                 put_unaligned_le16(0, req->buf);
1203                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1204                         break;
1205                 f = cdev->config->interface[intf];
1206                 if (!f)
1207                         break;
1208                 status = f->get_status ? f->get_status(f) : 0;
1209                 if (status < 0)
1210                         break;
1211                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1212                 break;
1213         /*
1214          * Function drivers should handle SetFeature/ClearFeature
1215          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1216          * only for the first interface of the function
1217          */
1218         case USB_REQ_CLEAR_FEATURE:
1219         case USB_REQ_SET_FEATURE:
1220                 if (!gadget_is_superspeed(gadget))
1221                         goto unknown;
1222                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1223                         goto unknown;
1224                 switch (w_value) {
1225                 case USB_INTRF_FUNC_SUSPEND:
1226                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1227                                 break;
1228                         f = cdev->config->interface[intf];
1229                         if (!f)
1230                                 break;
1231                         value = 0;
1232                         if (f->func_suspend)
1233                                 value = f->func_suspend(f, w_index >> 8);
1234                         if (value < 0) {
1235                                 ERROR(cdev,
1236                                       "func_suspend() returned error %d\n",
1237                                       value);
1238                                 value = 0;
1239                         }
1240                         break;
1241                 }
1242                 break;
1243         default:
1244 unknown:
1245                 VDBG(cdev,
1246                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1247                         ctrl->bRequestType, ctrl->bRequest,
1248                         w_value, w_index, w_length);
1249
1250                 /* functions always handle their interfaces and endpoints...
1251                  * punt other recipients (other, WUSB, ...) to the current
1252                  * configuration code.
1253                  *
1254                  * REVISIT it could make sense to let the composite device
1255                  * take such requests too, if that's ever needed:  to work
1256                  * in config 0, etc.
1257                  */
1258                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1259                 case USB_RECIP_INTERFACE:
1260                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1261                                 break;
1262                         f = cdev->config->interface[intf];
1263                         break;
1264
1265                 case USB_RECIP_ENDPOINT:
1266                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1267                         list_for_each_entry(f, &cdev->config->functions, list) {
1268                                 if (test_bit(endp, f->endpoints))
1269                                         break;
1270                         }
1271                         if (&f->list == &cdev->config->functions)
1272                                 f = NULL;
1273                         break;
1274                 }
1275
1276                 if (f && f->setup)
1277                         value = f->setup(f, ctrl);
1278                 else {
1279                         struct usb_configuration        *c;
1280
1281                         c = cdev->config;
1282                         if (c && c->setup)
1283                                 value = c->setup(c, ctrl);
1284                 }
1285
1286                 goto done;
1287         }
1288
1289         /* respond with data transfer before status phase? */
1290         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1291                 req->length = value;
1292                 req->zero = value < w_length;
1293                 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1294                 if (value < 0) {
1295                         DBG(cdev, "ep_queue --> %d\n", value);
1296                         req->status = 0;
1297                         composite_setup_complete(gadget->ep0, req);
1298                 }
1299         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1300                 WARN(cdev,
1301                         "%s: Delayed status not supported for w_length != 0",
1302                         __func__);
1303         }
1304
1305 done:
1306         /* device either stalls (value < 0) or reports success */
1307         return value;
1308 }
1309
1310 static void composite_disconnect(struct usb_gadget *gadget)
1311 {
1312         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1313         unsigned long                   flags;
1314
1315         /* REVISIT:  should we have config and device level
1316          * disconnect callbacks?
1317          */
1318         spin_lock_irqsave(&cdev->lock, flags);
1319         if (cdev->config)
1320                 reset_config(cdev);
1321         if (composite->disconnect)
1322                 composite->disconnect(cdev);
1323         spin_unlock_irqrestore(&cdev->lock, flags);
1324 }
1325
1326 /*-------------------------------------------------------------------------*/
1327
1328 static ssize_t composite_show_suspended(struct device *dev,
1329                                         struct device_attribute *attr,
1330                                         char *buf)
1331 {
1332         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1333         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1334
1335         return sprintf(buf, "%d\n", cdev->suspended);
1336 }
1337
1338 static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
1339
1340 static void
1341 composite_unbind(struct usb_gadget *gadget)
1342 {
1343         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1344
1345         /* composite_disconnect() must already have been called
1346          * by the underlying peripheral controller driver!
1347          * so there's no i/o concurrency that could affect the
1348          * state protected by cdev->lock.
1349          */
1350         WARN_ON(cdev->config);
1351
1352         while (!list_empty(&cdev->configs)) {
1353                 struct usb_configuration        *c;
1354
1355                 c = list_first_entry(&cdev->configs,
1356                                 struct usb_configuration, list);
1357                 while (!list_empty(&c->functions)) {
1358                         struct usb_function             *f;
1359
1360                         f = list_first_entry(&c->functions,
1361                                         struct usb_function, list);
1362                         list_del(&f->list);
1363                         if (f->unbind) {
1364                                 DBG(cdev, "unbind function '%s'/%p\n",
1365                                                 f->name, f);
1366                                 f->unbind(c, f);
1367                                 /* may free memory for "f" */
1368                         }
1369                 }
1370                 list_del(&c->list);
1371                 if (c->unbind) {
1372                         DBG(cdev, "unbind config '%s'/%p\n", c->label, c);
1373                         c->unbind(c);
1374                         /* may free memory for "c" */
1375                 }
1376         }
1377         if (composite->unbind)
1378                 composite->unbind(cdev);
1379
1380         if (cdev->req) {
1381                 kfree(cdev->req->buf);
1382                 usb_ep_free_request(gadget->ep0, cdev->req);
1383         }
1384         device_remove_file(&gadget->dev, &dev_attr_suspended);
1385         kfree(cdev);
1386         set_gadget_data(gadget, NULL);
1387         composite = NULL;
1388 }
1389
1390 static u8 override_id(struct usb_composite_dev *cdev, u8 *desc)
1391 {
1392         if (!*desc) {
1393                 int ret = usb_string_id(cdev);
1394                 if (unlikely(ret < 0))
1395                         WARNING(cdev, "failed to override string ID\n");
1396                 else
1397                         *desc = ret;
1398         }
1399
1400         return *desc;
1401 }
1402
1403 static int composite_bind(struct usb_gadget *gadget)
1404 {
1405         struct usb_composite_dev        *cdev;
1406         int                             status = -ENOMEM;
1407
1408         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1409         if (!cdev)
1410                 return status;
1411
1412         spin_lock_init(&cdev->lock);
1413         cdev->gadget = gadget;
1414         set_gadget_data(gadget, cdev);
1415         INIT_LIST_HEAD(&cdev->configs);
1416
1417         /* preallocate control response and buffer */
1418         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1419         if (!cdev->req)
1420                 goto fail;
1421         cdev->req->buf = kmalloc(USB_BUFSIZ, GFP_KERNEL);
1422         if (!cdev->req->buf)
1423                 goto fail;
1424         cdev->req->complete = composite_setup_complete;
1425         gadget->ep0->driver_data = cdev;
1426
1427         cdev->bufsiz = USB_BUFSIZ;
1428         cdev->driver = composite;
1429
1430         /*
1431          * As per USB compliance update, a device that is actively drawing
1432          * more than 100mA from USB must report itself as bus-powered in
1433          * the GetStatus(DEVICE) call.
1434          */
1435         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1436                 usb_gadget_set_selfpowered(gadget);
1437
1438         /* interface and string IDs start at zero via kzalloc.
1439          * we force endpoints to start unassigned; few controller
1440          * drivers will zero ep->driver_data.
1441          */
1442         usb_ep_autoconfig_reset(cdev->gadget);
1443
1444         /* composite gadget needs to assign strings for whole device (like
1445          * serial number), register function drivers, potentially update
1446          * power state and consumption, etc
1447          */
1448         status = composite_gadget_bind(cdev);
1449         if (status < 0)
1450                 goto fail;
1451
1452         cdev->desc = *composite->dev;
1453
1454         /* standardized runtime overrides for device ID data */
1455         if (idVendor)
1456                 cdev->desc.idVendor = cpu_to_le16(idVendor);
1457         if (idProduct)
1458                 cdev->desc.idProduct = cpu_to_le16(idProduct);
1459         if (bcdDevice)
1460                 cdev->desc.bcdDevice = cpu_to_le16(bcdDevice);
1461
1462         /* string overrides */
1463         if (iManufacturer || !cdev->desc.iManufacturer) {
1464                 if (!iManufacturer && !composite->iManufacturer &&
1465                     !*composite_manufacturer)
1466                         snprintf(composite_manufacturer,
1467                                  sizeof composite_manufacturer,
1468                                  "%s %s with %s",
1469                                  init_utsname()->sysname,
1470                                  init_utsname()->release,
1471                                  gadget->name);
1472
1473                 cdev->manufacturer_override =
1474                         override_id(cdev, &cdev->desc.iManufacturer);
1475         }
1476
1477         if (iProduct || (!cdev->desc.iProduct && composite->iProduct))
1478                 cdev->product_override =
1479                         override_id(cdev, &cdev->desc.iProduct);
1480
1481         if (iSerialNumber)
1482                 cdev->serial_override =
1483                         override_id(cdev, &cdev->desc.iSerialNumber);
1484
1485         /* has userspace failed to provide a serial number? */
1486         if (composite->needs_serial && !cdev->desc.iSerialNumber)
1487                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1488
1489         /* finish up */
1490         status = device_create_file(&gadget->dev, &dev_attr_suspended);
1491         if (status)
1492                 goto fail;
1493
1494         INFO(cdev, "%s ready\n", composite->name);
1495         return 0;
1496
1497 fail:
1498         composite_unbind(gadget);
1499         return status;
1500 }
1501
1502 /*-------------------------------------------------------------------------*/
1503
1504 static void
1505 composite_suspend(struct usb_gadget *gadget)
1506 {
1507         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1508         struct usb_function             *f;
1509
1510         /* REVISIT:  should we have config level
1511          * suspend/resume callbacks?
1512          */
1513         DBG(cdev, "suspend\n");
1514         if (cdev->config) {
1515                 list_for_each_entry(f, &cdev->config->functions, list) {
1516                         if (f->suspend)
1517                                 f->suspend(f);
1518                 }
1519         }
1520         if (composite->suspend)
1521                 composite->suspend(cdev);
1522
1523         cdev->suspended = 1;
1524
1525         usb_gadget_vbus_draw(gadget, 2);
1526 }
1527
1528 static void
1529 composite_resume(struct usb_gadget *gadget)
1530 {
1531         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1532         struct usb_function             *f;
1533         u8                              maxpower;
1534
1535         /* REVISIT:  should we have config level
1536          * suspend/resume callbacks?
1537          */
1538         DBG(cdev, "resume\n");
1539         if (composite->resume)
1540                 composite->resume(cdev);
1541         if (cdev->config) {
1542                 list_for_each_entry(f, &cdev->config->functions, list) {
1543                         if (f->resume)
1544                                 f->resume(f);
1545                 }
1546
1547                 maxpower = cdev->config->bMaxPower;
1548
1549                 usb_gadget_vbus_draw(gadget, maxpower ?
1550                         (2 * maxpower) : CONFIG_USB_GADGET_VBUS_DRAW);
1551         }
1552
1553         cdev->suspended = 0;
1554 }
1555
1556 /*-------------------------------------------------------------------------*/
1557
1558 static struct usb_gadget_driver composite_driver = {
1559 #ifdef CONFIG_USB_GADGET_SUPERSPEED
1560         .speed          = USB_SPEED_SUPER,
1561 #else
1562         .speed          = USB_SPEED_HIGH,
1563 #endif
1564
1565         .unbind         = composite_unbind,
1566
1567         .setup          = composite_setup,
1568         .disconnect     = composite_disconnect,
1569
1570         .suspend        = composite_suspend,
1571         .resume         = composite_resume,
1572
1573         .driver = {
1574                 .owner          = THIS_MODULE,
1575         },
1576 };
1577
1578 /**
1579  * usb_composite_probe() - register a composite driver
1580  * @driver: the driver to register
1581  * @bind: the callback used to allocate resources that are shared across the
1582  *      whole device, such as string IDs, and add its configurations using
1583  *      @usb_add_config().  This may fail by returning a negative errno
1584  *      value; it should return zero on successful initialization.
1585  * Context: single threaded during gadget setup
1586  *
1587  * This function is used to register drivers using the composite driver
1588  * framework.  The return value is zero, or a negative errno value.
1589  * Those values normally come from the driver's @bind method, which does
1590  * all the work of setting up the driver to match the hardware.
1591  *
1592  * On successful return, the gadget is ready to respond to requests from
1593  * the host, unless one of its components invokes usb_gadget_disconnect()
1594  * while it was binding.  That would usually be done in order to wait for
1595  * some userspace participation.
1596  */
1597 int usb_composite_probe(struct usb_composite_driver *driver,
1598                                int (*bind)(struct usb_composite_dev *cdev))
1599 {
1600         if (!driver || !driver->dev || !bind || composite)
1601                 return -EINVAL;
1602
1603         if (!driver->name)
1604                 driver->name = "composite";
1605         if (!driver->iProduct)
1606                 driver->iProduct = driver->name;
1607         composite_driver.function =  (char *) driver->name;
1608         composite_driver.driver.name = driver->name;
1609         composite_driver.speed = min((u8)composite_driver.speed,
1610                                      (u8)driver->max_speed);
1611         composite = driver;
1612         composite_gadget_bind = bind;
1613
1614         return usb_gadget_probe_driver(&composite_driver, composite_bind);
1615 }
1616
1617 /**
1618  * usb_composite_unregister() - unregister a composite driver
1619  * @driver: the driver to unregister
1620  *
1621  * This function is used to unregister drivers using the composite
1622  * driver framework.
1623  */
1624 void usb_composite_unregister(struct usb_composite_driver *driver)
1625 {
1626         if (composite != driver)
1627                 return;
1628         usb_gadget_unregister_driver(&composite_driver);
1629 }
1630
1631 /**
1632  * usb_composite_setup_continue() - Continue with the control transfer
1633  * @cdev: the composite device who's control transfer was kept waiting
1634  *
1635  * This function must be called by the USB function driver to continue
1636  * with the control transfer's data/status stage in case it had requested to
1637  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1638  * can request the composite framework to delay the setup request's data/status
1639  * stages by returning USB_GADGET_DELAYED_STATUS.
1640  */
1641 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1642 {
1643         int                     value;
1644         struct usb_request      *req = cdev->req;
1645         unsigned long           flags;
1646
1647         DBG(cdev, "%s\n", __func__);
1648         spin_lock_irqsave(&cdev->lock, flags);
1649
1650         if (cdev->delayed_status == 0) {
1651                 WARN(cdev, "%s: Unexpected call\n", __func__);
1652
1653         } else if (--cdev->delayed_status == 0) {
1654                 DBG(cdev, "%s: Completing delayed status\n", __func__);
1655                 req->length = 0;
1656                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1657                 if (value < 0) {
1658                         DBG(cdev, "ep_queue --> %d\n", value);
1659                         req->status = 0;
1660                         composite_setup_complete(cdev->gadget->ep0, req);
1661                 }
1662         }
1663
1664         spin_unlock_irqrestore(&cdev->lock, flags);
1665 }
1666