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 static struct usb_gadget_strings **get_containers_gs(
  32                 struct usb_gadget_string_container *uc)
  33 {
  34         return (struct usb_gadget_strings **)uc->stash;
  35 }
  36
  37 /**
  38  * next_ep_desc() - advance to the next EP descriptor
  39  * @t: currect pointer within descriptor array
  40  *
  41  * Return: next EP descriptor or NULL
  42  *
  43  * Iterate over @t until either EP descriptor found or
  44  * NULL (that indicates end of list) encountered
  45  */
  46 static struct usb_descriptor_header**
  47 next_ep_desc(struct usb_descriptor_header **t)
  48 {
  49         for (; *t; t++) {
  50                 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
  51                         return t;
  52         }
  53         return NULL;
  54 }
  55
  56 /*
  57  * for_each_ep_desc()- iterate over endpoint descriptors in the
  58  *              descriptors list
  59  * @start:      pointer within descriptor array.
  60  * @ep_desc:    endpoint descriptor to use as the loop cursor
  61  */
  62 #define for_each_ep_desc(start, ep_desc) \
  63         for (ep_desc = next_ep_desc(start); \
  64               ep_desc; ep_desc = next_ep_desc(ep_desc+1))
  65
  66 /**
  67  * config_ep_by_speed() - configures the given endpoint
  68  * according to gadget speed.
  69  * @g: pointer to the gadget
  70  * @f: usb function
  71  * @_ep: the endpoint to configure
  72  *
  73  * Return: error code, 0 on success
  74  *
  75  * This function chooses the right descriptors for a given
  76  * endpoint according to gadget speed and saves it in the
  77  * endpoint desc field. If the endpoint already has a descriptor
  78  * assigned to it - overwrites it with currently corresponding
  79  * descriptor. The endpoint maxpacket field is updated according
  80  * to the chosen descriptor.
  81  * Note: the supplied function should hold all the descriptors
  82  * for supported speeds
  83  */
  84 int config_ep_by_speed(struct usb_gadget *g,
  85                         struct usb_function *f,
  86                         struct usb_ep *_ep)
  87 {
  88         struct usb_composite_dev        *cdev = get_gadget_data(g);
  89         struct usb_endpoint_descriptor *chosen_desc = NULL;
  90         struct usb_descriptor_header **speed_desc = NULL;
  91
  92         struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
  93         int want_comp_desc = 0;
  94
  95         struct usb_descriptor_header **d_spd; /* cursor for speed desc */
  96
  97         if (!g || !f || !_ep)
  98                 return -EIO;
  99
 100         /* select desired speed */
 101         switch (g->speed) {
 102         case USB_SPEED_SUPER:
 103                 if (gadget_is_superspeed(g)) {
 104                         speed_desc = f->ss_descriptors;
 105                         want_comp_desc = 1;
 106                         break;
 107                 }
 108                 /* else: Fall trough */
 109         case USB_SPEED_HIGH:
 110                 if (gadget_is_dualspeed(g)) {
 111                         speed_desc = f->hs_descriptors;
 112                         break;
 113                 }
 114                 /* else: fall through */
 115         default:
 116                 speed_desc = f->fs_descriptors;
 117         }
 118         /* find descriptors */
 119         for_each_ep_desc(speed_desc, d_spd) {
 120                 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 121                 if (chosen_desc->bEndpointAddress == _ep->address)
 122                         goto ep_found;
 123         }
 124         return -EIO;
 125
 126 ep_found:
 127         /* commit results */
 128         _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 129         _ep->desc = chosen_desc;
 130         _ep->comp_desc = NULL;
 131         _ep->maxburst = 0;
 132         _ep->mult = 0;
 133         if (!want_comp_desc)
 134                 return 0;
 135
 136         /*
 137          * Companion descriptor should follow EP descriptor
 138          * USB 3.0 spec, #9.6.7
 139          */
 140         comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 141         if (!comp_desc ||
 142             (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 143                 return -EIO;
 144         _ep->comp_desc = comp_desc;
 145         if (g->speed == USB_SPEED_SUPER) {
 146                 switch (usb_endpoint_type(_ep->desc)) {
 147                 case USB_ENDPOINT_XFER_ISOC:
 148                         /* mult: bits 1:0 of bmAttributes */
 149                         _ep->mult = comp_desc->bmAttributes & 0x3;
 150                 case USB_ENDPOINT_XFER_BULK:
 151                 case USB_ENDPOINT_XFER_INT:
 152                         _ep->maxburst = comp_desc->bMaxBurst + 1;
 153                         break;
 154                 default:
 155                         if (comp_desc->bMaxBurst != 0)
 156                                 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 157                         _ep->maxburst = 1;
 158                         break;
 159                 }
 160         }
 161         return 0;
 162 }
 163 EXPORT_SYMBOL_GPL(config_ep_by_speed);
 164
 165 /**
 166  * usb_add_function() - add a function to a configuration
 167  * @config: the configuration
 168  * @function: the function being added
 169  * Context: single threaded during gadget setup
 170  *
 171  * After initialization, each configuration must have one or more
 172  * functions added to it.  Adding a function involves calling its @bind()
 173  * method to allocate resources such as interface and string identifiers
 174  * and endpoints.
 175  *
 176  * This function returns the value of the function's bind(), which is
 177  * zero for success else a negative errno value.
 178  */
 179 int usb_add_function(struct usb_configuration *config,
 180                 struct usb_function *function)
 181 {
 182         int     value = -EINVAL;
 183
 184         DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 185                         function->name, function,
 186                         config->label, config);
 187
 188         if (!function->set_alt || !function->disable)
 189                 goto done;
 190
 191         function->config = config;
 192         list_add_tail(&function->list, &config->functions);
 193
 194         /* REVISIT *require* function->bind? */
 195         if (function->bind) {
 196                 value = function->bind(config, function);
 197                 if (value < 0) {
 198                         list_del(&function->list);
 199                         function->config = NULL;
 200                 }
 201         } else
 202                 value = 0;
 203
 204         /* We allow configurations that don't work at both speeds.
 205          * If we run into a lowspeed Linux system, treat it the same
 206          * as full speed ... it's the function drivers that will need
 207          * to avoid bulk and ISO transfers.
 208          */
 209         if (!config->fullspeed && function->fs_descriptors)
 210                 config->fullspeed = true;
 211         if (!config->highspeed && function->hs_descriptors)
 212                 config->highspeed = true;
 213         if (!config->superspeed && function->ss_descriptors)
 214                 config->superspeed = true;
 215
 216 done:
 217         if (value)
 218                 DBG(config->cdev, "adding '%s'/%p --> %d\n",
 219                                 function->name, function, value);
 220         return value;
 221 }
 222 EXPORT_SYMBOL_GPL(usb_add_function);
 223
 224 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 225 {
 226         if (f->disable)
 227                 f->disable(f);
 228
 229         bitmap_zero(f->endpoints, 32);
 230         list_del(&f->list);
 231         if (f->unbind)
 232                 f->unbind(c, f);
 233 }
 234 EXPORT_SYMBOL_GPL(usb_remove_function);
 235
 236 /**
 237  * usb_function_deactivate - prevent function and gadget enumeration
 238  * @function: the function that isn't yet ready to respond
 239  *
 240  * Blocks response of the gadget driver to host enumeration by
 241  * preventing the data line pullup from being activated.  This is
 242  * normally called during @bind() processing to change from the
 243  * initial "ready to respond" state, or when a required resource
 244  * becomes available.
 245  *
 246  * For example, drivers that serve as a passthrough to a userspace
 247  * daemon can block enumeration unless that daemon (such as an OBEX,
 248  * MTP, or print server) is ready to handle host requests.
 249  *
 250  * Not all systems support software control of their USB peripheral
 251  * data pullups.
 252  *
 253  * Returns zero on success, else negative errno.
 254  */
 255 int usb_function_deactivate(struct usb_function *function)
 256 {
 257         struct usb_composite_dev        *cdev = function->config->cdev;
 258         unsigned long                   flags;
 259         int                             status = 0;
 260
 261         spin_lock_irqsave(&cdev->lock, flags);
 262
 263         if (cdev->deactivations == 0)
 264                 status = usb_gadget_disconnect(cdev->gadget);
 265         if (status == 0)
 266                 cdev->deactivations++;
 267
 268         spin_unlock_irqrestore(&cdev->lock, flags);
 269         return status;
 270 }
 271 EXPORT_SYMBOL_GPL(usb_function_deactivate);
 272
 273 /**
 274  * usb_function_activate - allow function and gadget enumeration
 275  * @function: function on which usb_function_activate() was called
 276  *
 277  * Reverses effect of usb_function_deactivate().  If no more functions
 278  * are delaying their activation, the gadget driver will respond to
 279  * host enumeration procedures.
 280  *
 281  * Returns zero on success, else negative errno.
 282  */
 283 int usb_function_activate(struct usb_function *function)
 284 {
 285         struct usb_composite_dev        *cdev = function->config->cdev;
 286         unsigned long                   flags;
 287         int                             status = 0;
 288
 289         spin_lock_irqsave(&cdev->lock, flags);
 290
 291         if (WARN_ON(cdev->deactivations == 0))
 292                 status = -EINVAL;
 293         else {
 294                 cdev->deactivations--;
 295                 if (cdev->deactivations == 0)
 296                         status = usb_gadget_connect(cdev->gadget);
 297         }
 298
 299         spin_unlock_irqrestore(&cdev->lock, flags);
 300         return status;
 301 }
 302 EXPORT_SYMBOL_GPL(usb_function_activate);
 303
 304 /**
 305  * usb_interface_id() - allocate an unused interface ID
 306  * @config: configuration associated with the interface
 307  * @function: function handling the interface
 308  * Context: single threaded during gadget setup
 309  *
 310  * usb_interface_id() is called from usb_function.bind() callbacks to
 311  * allocate new interface IDs.  The function driver will then store that
 312  * ID in interface, association, CDC union, and other descriptors.  It
 313  * will also handle any control requests targeted at that interface,
 314  * particularly changing its altsetting via set_alt().  There may
 315  * also be class-specific or vendor-specific requests to handle.
 316  *
 317  * All interface identifier should be allocated using this routine, to
 318  * ensure that for example different functions don't wrongly assign
 319  * different meanings to the same identifier.  Note that since interface
 320  * identifiers are configuration-specific, functions used in more than
 321  * one configuration (or more than once in a given configuration) need
 322  * multiple versions of the relevant descriptors.
 323  *
 324  * Returns the interface ID which was allocated; or -ENODEV if no
 325  * more interface IDs can be allocated.
 326  */
 327 int usb_interface_id(struct usb_configuration *config,
 328                 struct usb_function *function)
 329 {
 330         unsigned id = config->next_interface_id;
 331
 332         if (id < MAX_CONFIG_INTERFACES) {
 333                 config->interface[id] = function;
 334                 config->next_interface_id = id + 1;
 335                 return id;
 336         }
 337         return -ENODEV;
 338 }
 339 EXPORT_SYMBOL_GPL(usb_interface_id);
 340
 341 static u8 encode_bMaxPower(enum usb_device_speed speed,
 342                 struct usb_configuration *c)
 343 {
 344         unsigned val;
 345
 346         if (c->MaxPower)
 347                 val = c->MaxPower;
 348         else
 349                 val = CONFIG_USB_GADGET_VBUS_DRAW;
 350         if (!val)
 351                 return 0;
 352         switch (speed) {
 353         case USB_SPEED_SUPER:
 354                 return DIV_ROUND_UP(val, 8);
 355         default:
 356                 return DIV_ROUND_UP(val, 2);
 357         }
 358 }
 359
 360 static int config_buf(struct usb_configuration *config,
 361                 enum usb_device_speed speed, void *buf, u8 type)
 362 {
 363         struct usb_config_descriptor    *c = buf;
 364         void                            *next = buf + USB_DT_CONFIG_SIZE;
 365         int                             len;
 366         struct usb_function             *f;
 367         int                             status;
 368
 369         len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 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 = encode_bMaxPower(speed, config);
 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->fs_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_DEFAULT_U1_DEV_EXIT_LAT;
 555                 dcd_config_params.bU2DevExitLat =
 556                         cpu_to_le16(USB_DEFAULT_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         cdev->delayed_status = 0;
 597 }
 598
 599 static int set_config(struct usb_composite_dev *cdev,
 600                 const struct usb_ctrlrequest *ctrl, unsigned number)
 601 {
 602         struct usb_gadget       *gadget = cdev->gadget;
 603         struct usb_configuration *c = NULL;
 604         int                     result = -EINVAL;
 605         unsigned                power = gadget_is_otg(gadget) ? 8 : 100;
 606         int                     tmp;
 607
 608         if (number) {
 609                 list_for_each_entry(c, &cdev->configs, list) {
 610                         if (c->bConfigurationValue == number) {
 611                                 /*
 612                                  * We disable the FDs of the previous
 613                                  * configuration only if the new configuration
 614                                  * is a valid one
 615                                  */
 616                                 if (cdev->config)
 617                                         reset_config(cdev);
 618                                 result = 0;
 619                                 break;
 620                         }
 621                 }
 622                 if (result < 0)
 623                         goto done;
 624         } else { /* Zero configuration value - need to reset the config */
 625                 if (cdev->config)
 626                         reset_config(cdev);
 627                 result = 0;
 628         }
 629
 630         INFO(cdev, "%s config #%d: %s\n",
 631              usb_speed_string(gadget->speed),
 632              number, c ? c->label : "unconfigured");
 633
 634         if (!c)
 635                 goto done;
 636
 637         cdev->config = c;
 638
 639         /* Initialize all interfaces by setting them to altsetting zero. */
 640         for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 641                 struct usb_function     *f = c->interface[tmp];
 642                 struct usb_descriptor_header **descriptors;
 643
 644                 if (!f)
 645                         break;
 646
 647                 /*
 648                  * Record which endpoints are used by the function. This is used
 649                  * to dispatch control requests targeted at that endpoint to the
 650                  * function's setup callback instead of the current
 651                  * configuration's setup callback.
 652                  */
 653                 switch (gadget->speed) {
 654                 case USB_SPEED_SUPER:
 655                         descriptors = f->ss_descriptors;
 656                         break;
 657                 case USB_SPEED_HIGH:
 658                         descriptors = f->hs_descriptors;
 659                         break;
 660                 default:
 661                         descriptors = f->fs_descriptors;
 662                 }
 663
 664                 for (; *descriptors; ++descriptors) {
 665                         struct usb_endpoint_descriptor *ep;
 666                         int addr;
 667
 668                         if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 669                                 continue;
 670
 671                         ep = (struct usb_endpoint_descriptor *)*descriptors;
 672                         addr = ((ep->bEndpointAddress & 0x80) >> 3)
 673                              |  (ep->bEndpointAddress & 0x0f);
 674                         set_bit(addr, f->endpoints);
 675                 }
 676
 677                 result = f->set_alt(f, tmp, 0);
 678                 if (result < 0) {
 679                         DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 680                                         tmp, f->name, f, result);
 681
 682                         reset_config(cdev);
 683                         goto done;
 684                 }
 685
 686                 if (result == USB_GADGET_DELAYED_STATUS) {
 687                         DBG(cdev,
 688                          "%s: interface %d (%s) requested delayed status\n",
 689                                         __func__, tmp, f->name);
 690                         cdev->delayed_status++;
 691                         DBG(cdev, "delayed_status count %d\n",
 692                                         cdev->delayed_status);
 693                 }
 694         }
 695
 696         /* when we return, be sure our power usage is valid */
 697         power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
 698 done:
 699         usb_gadget_vbus_draw(gadget, power);
 700         if (result >= 0 && cdev->delayed_status)
 701                 result = USB_GADGET_DELAYED_STATUS;
 702         return result;
 703 }
 704
 705 int usb_add_config_only(struct usb_composite_dev *cdev,
 706                 struct usb_configuration *config)
 707 {
 708         struct usb_configuration *c;
 709
 710         if (!config->bConfigurationValue)
 711                 return -EINVAL;
 712
 713         /* Prevent duplicate configuration identifiers */
 714         list_for_each_entry(c, &cdev->configs, list) {
 715                 if (c->bConfigurationValue == config->bConfigurationValue)
 716                         return -EBUSY;
 717         }
 718
 719         config->cdev = cdev;
 720         list_add_tail(&config->list, &cdev->configs);
 721
 722         INIT_LIST_HEAD(&config->functions);
 723         config->next_interface_id = 0;
 724         memset(config->interface, 0, sizeof(config->interface));
 725
 726         return 0;
 727 }
 728 EXPORT_SYMBOL_GPL(usb_add_config_only);
 729
 730 /**
 731  * usb_add_config() - add a configuration to a device.
 732  * @cdev: wraps the USB gadget
 733  * @config: the configuration, with bConfigurationValue assigned
 734  * @bind: the configuration's bind function
 735  * Context: single threaded during gadget setup
 736  *
 737  * One of the main tasks of a composite @bind() routine is to
 738  * add each of the configurations it supports, using this routine.
 739  *
 740  * This function returns the value of the configuration's @bind(), which
 741  * is zero for success else a negative errno value.  Binding configurations
 742  * assigns global resources including string IDs, and per-configuration
 743  * resources such as interface IDs and endpoints.
 744  */
 745 int usb_add_config(struct usb_composite_dev *cdev,
 746                 struct usb_configuration *config,
 747                 int (*bind)(struct usb_configuration *))
 748 {
 749         int                             status = -EINVAL;
 750
 751         if (!bind)
 752                 goto done;
 753
 754         DBG(cdev, "adding config #%u '%s'/%p\n",
 755                         config->bConfigurationValue,
 756                         config->label, config);
 757
 758         status = usb_add_config_only(cdev, config);
 759         if (status)
 760                 goto done;
 761
 762         status = bind(config);
 763         if (status < 0) {
 764                 while (!list_empty(&config->functions)) {
 765                         struct usb_function             *f;
 766
 767                         f = list_first_entry(&config->functions,
 768                                         struct usb_function, list);
 769                         list_del(&f->list);
 770                         if (f->unbind) {
 771                                 DBG(cdev, "unbind function '%s'/%p\n",
 772                                         f->name, f);
 773                                 f->unbind(config, f);
 774                                 /* may free memory for "f" */
 775                         }
 776                 }
 777                 list_del(&config->list);
 778                 config->cdev = NULL;
 779         } else {
 780                 unsigned        i;
 781
 782                 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 783                         config->bConfigurationValue, config,
 784                         config->superspeed ? " super" : "",
 785                         config->highspeed ? " high" : "",
 786                         config->fullspeed
 787                                 ? (gadget_is_dualspeed(cdev->gadget)
 788                                         ? " full"
 789                                         : " full/low")
 790                                 : "");
 791
 792                 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
 793                         struct usb_function     *f = config->interface[i];
 794
 795                         if (!f)
 796                                 continue;
 797                         DBG(cdev, "  interface %d = %s/%p\n",
 798                                 i, f->name, f);
 799                 }
 800         }
 801
 802         /* set_alt(), or next bind(), sets up
 803          * ep->driver_data as needed.
 804          */
 805         usb_ep_autoconfig_reset(cdev->gadget);
 806
 807 done:
 808         if (status)
 809                 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
 810                                 config->bConfigurationValue, status);
 811         return status;
 812 }
 813 EXPORT_SYMBOL_GPL(usb_add_config);
 814
 815 static void remove_config(struct usb_composite_dev *cdev,
 816                               struct usb_configuration *config)
 817 {
 818         while (!list_empty(&config->functions)) {
 819                 struct usb_function             *f;
 820
 821                 f = list_first_entry(&config->functions,
 822                                 struct usb_function, list);
 823                 list_del(&f->list);
 824                 if (f->unbind) {
 825                         DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
 826                         f->unbind(config, f);
 827                         /* may free memory for "f" */
 828                 }
 829         }
 830         list_del(&config->list);
 831         if (config->unbind) {
 832                 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
 833                 config->unbind(config);
 834                         /* may free memory for "c" */
 835         }
 836 }
 837
 838 /**
 839  * usb_remove_config() - remove a configuration from a device.
 840  * @cdev: wraps the USB gadget
 841  * @config: the configuration
 842  *
 843  * Drivers must call usb_gadget_disconnect before calling this function
 844  * to disconnect the device from the host and make sure the host will not
 845  * try to enumerate the device while we are changing the config list.
 846  */
 847 void usb_remove_config(struct usb_composite_dev *cdev,
 848                       struct usb_configuration *config)
 849 {
 850         unsigned long flags;
 851
 852         spin_lock_irqsave(&cdev->lock, flags);
 853
 854         if (cdev->config == config)
 855                 reset_config(cdev);
 856
 857         spin_unlock_irqrestore(&cdev->lock, flags);
 858
 859         remove_config(cdev, config);
 860 }
 861
 862 /*-------------------------------------------------------------------------*/
 863
 864 /* We support strings in multiple languages ... string descriptor zero
 865  * says which languages are supported.  The typical case will be that
 866  * only one language (probably English) is used, with I18N handled on
 867  * the host side.
 868  */
 869
 870 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
 871 {
 872         const struct usb_gadget_strings *s;
 873         __le16                          language;
 874         __le16                          *tmp;
 875
 876         while (*sp) {
 877                 s = *sp;
 878                 language = cpu_to_le16(s->language);
 879                 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
 880                         if (*tmp == language)
 881                                 goto repeat;
 882                 }
 883                 *tmp++ = language;
 884 repeat:
 885                 sp++;
 886         }
 887 }
 888
 889 static int lookup_string(
 890         struct usb_gadget_strings       **sp,
 891         void                            *buf,
 892         u16                             language,
 893         int                             id
 894 )
 895 {
 896         struct usb_gadget_strings       *s;
 897         int                             value;
 898
 899         while (*sp) {
 900                 s = *sp++;
 901                 if (s->language != language)
 902                         continue;
 903                 value = usb_gadget_get_string(s, id, buf);
 904                 if (value > 0)
 905                         return value;
 906         }
 907         return -EINVAL;
 908 }
 909
 910 static int get_string(struct usb_composite_dev *cdev,
 911                 void *buf, u16 language, int id)
 912 {
 913         struct usb_composite_driver     *composite = cdev->driver;
 914         struct usb_gadget_string_container *uc;
 915         struct usb_configuration        *c;
 916         struct usb_function             *f;
 917         int                             len;
 918
 919         /* Yes, not only is USB's I18N support probably more than most
 920          * folk will ever care about ... also, it's all supported here.
 921          * (Except for UTF8 support for Unicode's "Astral Planes".)
 922          */
 923
 924         /* 0 == report all available language codes */
 925         if (id == 0) {
 926                 struct usb_string_descriptor    *s = buf;
 927                 struct usb_gadget_strings       **sp;
 928
 929                 memset(s, 0, 256);
 930                 s->bDescriptorType = USB_DT_STRING;
 931
 932                 sp = composite->strings;
 933                 if (sp)
 934                         collect_langs(sp, s->wData);
 935
 936                 list_for_each_entry(c, &cdev->configs, list) {
 937                         sp = c->strings;
 938                         if (sp)
 939                                 collect_langs(sp, s->wData);
 940
 941                         list_for_each_entry(f, &c->functions, list) {
 942                                 sp = f->strings;
 943                                 if (sp)
 944                                         collect_langs(sp, s->wData);
 945                         }
 946                 }
 947                 list_for_each_entry(uc, &cdev->gstrings, list) {
 948                         struct usb_gadget_strings **sp;
 949
 950                         sp = get_containers_gs(uc);
 951                         collect_langs(sp, s->wData);
 952                 }
 953
 954                 for (len = 0; len <= 126 && s->wData[len]; len++)
 955                         continue;
 956                 if (!len)
 957                         return -EINVAL;
 958
 959                 s->bLength = 2 * (len + 1);
 960                 return s->bLength;
 961         }
 962
 963         list_for_each_entry(uc, &cdev->gstrings, list) {
 964                 struct usb_gadget_strings **sp;
 965
 966                 sp = get_containers_gs(uc);
 967                 len = lookup_string(sp, buf, language, id);
 968                 if (len > 0)
 969                         return len;
 970         }
 971
 972         /* String IDs are device-scoped, so we look up each string
 973          * table we're told about.  These lookups are infrequent;
 974          * simpler-is-better here.
 975          */
 976         if (composite->strings) {
 977                 len = lookup_string(composite->strings, buf, language, id);
 978                 if (len > 0)
 979                         return len;
 980         }
 981         list_for_each_entry(c, &cdev->configs, list) {
 982                 if (c->strings) {
 983                         len = lookup_string(c->strings, buf, language, id);
 984                         if (len > 0)
 985                                 return len;
 986                 }
 987                 list_for_each_entry(f, &c->functions, list) {
 988                         if (!f->strings)
 989                                 continue;
 990                         len = lookup_string(f->strings, buf, language, id);
 991                         if (len > 0)
 992                                 return len;
 993                 }
 994         }
 995         return -EINVAL;
 996 }
 997
 998 /**
 999  * usb_string_id() - allocate an unused string ID
1000  * @cdev: the device whose string descriptor IDs are being allocated
1001  * Context: single threaded during gadget setup
1002  *
1003  * @usb_string_id() is called from bind() callbacks to allocate
1004  * string IDs.  Drivers for functions, configurations, or gadgets will
1005  * then store that ID in the appropriate descriptors and string table.
1006  *
1007  * All string identifier should be allocated using this,
1008  * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1009  * that for example different functions don't wrongly assign different
1010  * meanings to the same identifier.
1011  */
1012 int usb_string_id(struct usb_composite_dev *cdev)
1013 {
1014         if (cdev->next_string_id < 254) {
1015                 /* string id 0 is reserved by USB spec for list of
1016                  * supported languages */
1017                 /* 255 reserved as well? -- mina86 */
1018                 cdev->next_string_id++;
1019                 return cdev->next_string_id;
1020         }
1021         return -ENODEV;
1022 }
1023 EXPORT_SYMBOL_GPL(usb_string_id);
1024
1025 /**
1026  * usb_string_ids() - allocate unused string IDs in batch
1027  * @cdev: the device whose string descriptor IDs are being allocated
1028  * @str: an array of usb_string objects to assign numbers to
1029  * Context: single threaded during gadget setup
1030  *
1031  * @usb_string_ids() is called from bind() callbacks to allocate
1032  * string IDs.  Drivers for functions, configurations, or gadgets will
1033  * then copy IDs from the string table to the appropriate descriptors
1034  * and string table for other languages.
1035  *
1036  * All string identifier should be allocated using this,
1037  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1038  * example different functions don't wrongly assign different meanings
1039  * to the same identifier.
1040  */
1041 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1042 {
1043         int next = cdev->next_string_id;
1044
1045         for (; str->s; ++str) {
1046                 if (unlikely(next >= 254))
1047                         return -ENODEV;
1048                 str->id = ++next;
1049         }
1050
1051         cdev->next_string_id = next;
1052
1053         return 0;
1054 }
1055 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1056
1057 static struct usb_gadget_string_container *copy_gadget_strings(
1058                 struct usb_gadget_strings **sp, unsigned n_gstrings,
1059                 unsigned n_strings)
1060 {
1061         struct usb_gadget_string_container *uc;
1062         struct usb_gadget_strings **gs_array;
1063         struct usb_gadget_strings *gs;
1064         struct usb_string *s;
1065         unsigned mem;
1066         unsigned n_gs;
1067         unsigned n_s;
1068         void *stash;
1069
1070         mem = sizeof(*uc);
1071         mem += sizeof(void *) * (n_gstrings + 1);
1072         mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1073         mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1074         uc = kmalloc(mem, GFP_KERNEL);
1075         if (!uc)
1076                 return ERR_PTR(-ENOMEM);
1077         gs_array = get_containers_gs(uc);
1078         stash = uc->stash;
1079         stash += sizeof(void *) * (n_gstrings + 1);
1080         for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1081                 struct usb_string *org_s;
1082
1083                 gs_array[n_gs] = stash;
1084                 gs = gs_array[n_gs];
1085                 stash += sizeof(struct usb_gadget_strings);
1086                 gs->language = sp[n_gs]->language;
1087                 gs->strings = stash;
1088                 org_s = sp[n_gs]->strings;
1089
1090                 for (n_s = 0; n_s < n_strings; n_s++) {
1091                         s = stash;
1092                         stash += sizeof(struct usb_string);
1093                         if (org_s->s)
1094                                 s->s = org_s->s;
1095                         else
1096                                 s->s = "";
1097                         org_s++;
1098                 }
1099                 s = stash;
1100                 s->s = NULL;
1101                 stash += sizeof(struct usb_string);
1102
1103         }
1104         gs_array[n_gs] = NULL;
1105         return uc;
1106 }
1107
1108 /**
1109  * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1110  * @cdev: the device whose string descriptor IDs are being allocated
1111  * and attached.
1112  * @sp: an array of usb_gadget_strings to attach.
1113  * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1114  *
1115  * This function will create a deep copy of usb_gadget_strings and usb_string
1116  * and attach it to the cdev. The actual string (usb_string.s) will not be
1117  * copied but only a referenced will be made. The struct usb_gadget_strings
1118  * array may contain multiple languges and should be NULL terminated.
1119  * The ->language pointer of each struct usb_gadget_strings has to contain the
1120  * same amount of entries.
1121  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1122  * usb_string entry of es-ES containts the translation of the first usb_string
1123  * entry of en-US. Therefore both entries become the same id assign.
1124  */
1125 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1126                 struct usb_gadget_strings **sp, unsigned n_strings)
1127 {
1128         struct usb_gadget_string_container *uc;
1129         struct usb_gadget_strings **n_gs;
1130         unsigned n_gstrings = 0;
1131         unsigned i;
1132         int ret;
1133
1134         for (i = 0; sp[i]; i++)
1135                 n_gstrings++;
1136
1137         if (!n_gstrings)
1138                 return ERR_PTR(-EINVAL);
1139
1140         uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1141         if (IS_ERR(uc))
1142                 return ERR_PTR(PTR_ERR(uc));
1143
1144         n_gs = get_containers_gs(uc);
1145         ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1146         if (ret)
1147                 goto err;
1148
1149         for (i = 1; i < n_gstrings; i++) {
1150                 struct usb_string *m_s;
1151                 struct usb_string *s;
1152                 unsigned n;
1153
1154                 m_s = n_gs[0]->strings;
1155                 s = n_gs[i]->strings;
1156                 for (n = 0; n < n_strings; n++) {
1157                         s->id = m_s->id;
1158                         s++;
1159                         m_s++;
1160                 }
1161         }
1162         list_add_tail(&uc->list, &cdev->gstrings);
1163         return n_gs[0]->strings;
1164 err:
1165         kfree(uc);
1166         return ERR_PTR(ret);
1167 }
1168 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1169
1170 /**
1171  * usb_string_ids_n() - allocate unused string IDs in batch
1172  * @c: the device whose string descriptor IDs are being allocated
1173  * @n: number of string IDs to allocate
1174  * Context: single threaded during gadget setup
1175  *
1176  * Returns the first requested ID.  This ID and next @n-1 IDs are now
1177  * valid IDs.  At least provided that @n is non-zero because if it
1178  * is, returns last requested ID which is now very useful information.
1179  *
1180  * @usb_string_ids_n() is called from bind() callbacks to allocate
1181  * string IDs.  Drivers for functions, configurations, or gadgets will
1182  * then store that ID in the appropriate descriptors and string table.
1183  *
1184  * All string identifier should be allocated using this,
1185  * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1186  * example different functions don't wrongly assign different meanings
1187  * to the same identifier.
1188  */
1189 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1190 {
1191         unsigned next = c->next_string_id;
1192         if (unlikely(n > 254 || (unsigned)next + n > 254))
1193                 return -ENODEV;
1194         c->next_string_id += n;
1195         return next + 1;
1196 }
1197 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1198
1199 /*-------------------------------------------------------------------------*/
1200
1201 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1202 {
1203         if (req->status || req->actual != req->length)
1204                 DBG((struct usb_composite_dev *) ep->driver_data,
1205                                 "setup complete --> %d, %d/%d\n",
1206                                 req->status, req->actual, req->length);
1207 }
1208
1209 /*
1210  * The setup() callback implements all the ep0 functionality that's
1211  * not handled lower down, in hardware or the hardware driver(like
1212  * device and endpoint feature flags, and their status).  It's all
1213  * housekeeping for the gadget function we're implementing.  Most of
1214  * the work is in config and function specific setup.
1215  */
1216 int
1217 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1218 {
1219         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1220         struct usb_request              *req = cdev->req;
1221         int                             value = -EOPNOTSUPP;
1222         int                             status = 0;
1223         u16                             w_index = le16_to_cpu(ctrl->wIndex);
1224         u8                              intf = w_index & 0xFF;
1225         u16                             w_value = le16_to_cpu(ctrl->wValue);
1226         u16                             w_length = le16_to_cpu(ctrl->wLength);
1227         struct usb_function             *f = NULL;
1228         u8                              endp;
1229
1230         /* partial re-init of the response message; the function or the
1231          * gadget might need to intercept e.g. a control-OUT completion
1232          * when we delegate to it.
1233          */
1234         req->zero = 0;
1235         req->complete = composite_setup_complete;
1236         req->length = 0;
1237         gadget->ep0->driver_data = cdev;
1238
1239         switch (ctrl->bRequest) {
1240
1241         /* we handle all standard USB descriptors */
1242         case USB_REQ_GET_DESCRIPTOR:
1243                 if (ctrl->bRequestType != USB_DIR_IN)
1244                         goto unknown;
1245                 switch (w_value >> 8) {
1246
1247                 case USB_DT_DEVICE:
1248                         cdev->desc.bNumConfigurations =
1249                                 count_configs(cdev, USB_DT_DEVICE);
1250                         cdev->desc.bMaxPacketSize0 =
1251                                 cdev->gadget->ep0->maxpacket;
1252                         if (gadget_is_superspeed(gadget)) {
1253                                 if (gadget->speed >= USB_SPEED_SUPER) {
1254                                         cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1255                                         cdev->desc.bMaxPacketSize0 = 9;
1256                                 } else {
1257                                         cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1258                                 }
1259                         }
1260
1261                         value = min(w_length, (u16) sizeof cdev->desc);
1262                         memcpy(req->buf, &cdev->desc, value);
1263                         break;
1264                 case USB_DT_DEVICE_QUALIFIER:
1265                         if (!gadget_is_dualspeed(gadget) ||
1266                             gadget->speed >= USB_SPEED_SUPER)
1267                                 break;
1268                         device_qual(cdev);
1269                         value = min_t(int, w_length,
1270                                 sizeof(struct usb_qualifier_descriptor));
1271                         break;
1272                 case USB_DT_OTHER_SPEED_CONFIG:
1273                         if (!gadget_is_dualspeed(gadget) ||
1274                             gadget->speed >= USB_SPEED_SUPER)
1275                                 break;
1276                         /* FALLTHROUGH */
1277                 case USB_DT_CONFIG:
1278                         value = config_desc(cdev, w_value);
1279                         if (value >= 0)
1280                                 value = min(w_length, (u16) value);
1281                         break;
1282                 case USB_DT_STRING:
1283                         value = get_string(cdev, req->buf,
1284                                         w_index, w_value & 0xff);
1285                         if (value >= 0)
1286                                 value = min(w_length, (u16) value);
1287                         break;
1288                 case USB_DT_BOS:
1289                         if (gadget_is_superspeed(gadget)) {
1290                                 value = bos_desc(cdev);
1291                                 value = min(w_length, (u16) value);
1292                         }
1293                         break;
1294                 }
1295                 break;
1296
1297         /* any number of configs can work */
1298         case USB_REQ_SET_CONFIGURATION:
1299                 if (ctrl->bRequestType != 0)
1300                         goto unknown;
1301                 if (gadget_is_otg(gadget)) {
1302                         if (gadget->a_hnp_support)
1303                                 DBG(cdev, "HNP available\n");
1304                         else if (gadget->a_alt_hnp_support)
1305                                 DBG(cdev, "HNP on another port\n");
1306                         else
1307                                 VDBG(cdev, "HNP inactive\n");
1308                 }
1309                 spin_lock(&cdev->lock);
1310                 value = set_config(cdev, ctrl, w_value);
1311                 spin_unlock(&cdev->lock);
1312                 break;
1313         case USB_REQ_GET_CONFIGURATION:
1314                 if (ctrl->bRequestType != USB_DIR_IN)
1315                         goto unknown;
1316                 if (cdev->config)
1317                         *(u8 *)req->buf = cdev->config->bConfigurationValue;
1318                 else
1319                         *(u8 *)req->buf = 0;
1320                 value = min(w_length, (u16) 1);
1321                 break;
1322
1323         /* function drivers must handle get/set altsetting; if there's
1324          * no get() method, we know only altsetting zero works.
1325          */
1326         case USB_REQ_SET_INTERFACE:
1327                 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1328                         goto unknown;
1329                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1330                         break;
1331                 f = cdev->config->interface[intf];
1332                 if (!f)
1333                         break;
1334                 if (w_value && !f->set_alt)
1335                         break;
1336                 value = f->set_alt(f, w_index, w_value);
1337                 if (value == USB_GADGET_DELAYED_STATUS) {
1338                         DBG(cdev,
1339                          "%s: interface %d (%s) requested delayed status\n",
1340                                         __func__, intf, f->name);
1341                         cdev->delayed_status++;
1342                         DBG(cdev, "delayed_status count %d\n",
1343                                         cdev->delayed_status);
1344                 }
1345                 break;
1346         case USB_REQ_GET_INTERFACE:
1347                 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1348                         goto unknown;
1349                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1350                         break;
1351                 f = cdev->config->interface[intf];
1352                 if (!f)
1353                         break;
1354                 /* lots of interfaces only need altsetting zero... */
1355                 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1356                 if (value < 0)
1357                         break;
1358                 *((u8 *)req->buf) = value;
1359                 value = min(w_length, (u16) 1);
1360                 break;
1361
1362         /*
1363          * USB 3.0 additions:
1364          * Function driver should handle get_status request. If such cb
1365          * wasn't supplied we respond with default value = 0
1366          * Note: function driver should supply such cb only for the first
1367          * interface of the function
1368          */
1369         case USB_REQ_GET_STATUS:
1370                 if (!gadget_is_superspeed(gadget))
1371                         goto unknown;
1372                 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1373                         goto unknown;
1374                 value = 2;      /* This is the length of the get_status reply */
1375                 put_unaligned_le16(0, req->buf);
1376                 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1377                         break;
1378                 f = cdev->config->interface[intf];
1379                 if (!f)
1380                         break;
1381                 status = f->get_status ? f->get_status(f) : 0;
1382                 if (status < 0)
1383                         break;
1384                 put_unaligned_le16(status & 0x0000ffff, req->buf);
1385                 break;
1386         /*
1387          * Function drivers should handle SetFeature/ClearFeature
1388          * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1389          * only for the first interface of the function
1390          */
1391         case USB_REQ_CLEAR_FEATURE:
1392         case USB_REQ_SET_FEATURE:
1393                 if (!gadget_is_superspeed(gadget))
1394                         goto unknown;
1395                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1396                         goto unknown;
1397                 switch (w_value) {
1398                 case USB_INTRF_FUNC_SUSPEND:
1399                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1400                                 break;
1401                         f = cdev->config->interface[intf];
1402                         if (!f)
1403                                 break;
1404                         value = 0;
1405                         if (f->func_suspend)
1406                                 value = f->func_suspend(f, w_index >> 8);
1407                         if (value < 0) {
1408                                 ERROR(cdev,
1409                                       "func_suspend() returned error %d\n",
1410                                       value);
1411                                 value = 0;
1412                         }
1413                         break;
1414                 }
1415                 break;
1416         default:
1417 unknown:
1418                 VDBG(cdev,
1419                         "non-core control req%02x.%02x v%04x i%04x l%d\n",
1420                         ctrl->bRequestType, ctrl->bRequest,
1421                         w_value, w_index, w_length);
1422
1423                 /* functions always handle their interfaces and endpoints...
1424                  * punt other recipients (other, WUSB, ...) to the current
1425                  * configuration code.
1426                  *
1427                  * REVISIT it could make sense to let the composite device
1428                  * take such requests too, if that's ever needed:  to work
1429                  * in config 0, etc.
1430                  */
1431                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1432                 case USB_RECIP_INTERFACE:
1433                         if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1434                                 break;
1435                         f = cdev->config->interface[intf];
1436                         break;
1437
1438                 case USB_RECIP_ENDPOINT:
1439                         endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1440                         list_for_each_entry(f, &cdev->config->functions, list) {
1441                                 if (test_bit(endp, f->endpoints))
1442                                         break;
1443                         }
1444                         if (&f->list == &cdev->config->functions)
1445                                 f = NULL;
1446                         break;
1447                 }
1448
1449                 if (f && f->setup)
1450                         value = f->setup(f, ctrl);
1451                 else {
1452                         struct usb_configuration        *c;
1453
1454                         c = cdev->config;
1455                         if (c && c->setup)
1456                                 value = c->setup(c, ctrl);
1457                 }
1458
1459                 goto done;
1460         }
1461
1462         /* respond with data transfer before status phase? */
1463         if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1464                 req->length = value;
1465                 req->zero = value < w_length;
1466                 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1467                 if (value < 0) {
1468                         DBG(cdev, "ep_queue --> %d\n", value);
1469                         req->status = 0;
1470                         composite_setup_complete(gadget->ep0, req);
1471                 }
1472         } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1473                 WARN(cdev,
1474                         "%s: Delayed status not supported for w_length != 0",
1475                         __func__);
1476         }
1477
1478 done:
1479         /* device either stalls (value < 0) or reports success */
1480         return value;
1481 }
1482
1483 void composite_disconnect(struct usb_gadget *gadget)
1484 {
1485         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1486         unsigned long                   flags;
1487
1488         /* REVISIT:  should we have config and device level
1489          * disconnect callbacks?
1490          */
1491         spin_lock_irqsave(&cdev->lock, flags);
1492         if (cdev->config)
1493                 reset_config(cdev);
1494         if (cdev->driver->disconnect)
1495                 cdev->driver->disconnect(cdev);
1496         spin_unlock_irqrestore(&cdev->lock, flags);
1497 }
1498
1499 /*-------------------------------------------------------------------------*/
1500
1501 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
1502                               char *buf)
1503 {
1504         struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1505         struct usb_composite_dev *cdev = get_gadget_data(gadget);
1506
1507         return sprintf(buf, "%d\n", cdev->suspended);
1508 }
1509 static DEVICE_ATTR_RO(suspended);
1510
1511 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1512 {
1513         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1514
1515         /* composite_disconnect() must already have been called
1516          * by the underlying peripheral controller driver!
1517          * so there's no i/o concurrency that could affect the
1518          * state protected by cdev->lock.
1519          */
1520         WARN_ON(cdev->config);
1521
1522         while (!list_empty(&cdev->configs)) {
1523                 struct usb_configuration        *c;
1524                 c = list_first_entry(&cdev->configs,
1525                                 struct usb_configuration, list);
1526                 remove_config(cdev, c);
1527         }
1528         if (cdev->driver->unbind && unbind_driver)
1529                 cdev->driver->unbind(cdev);
1530
1531         composite_dev_cleanup(cdev);
1532
1533         kfree(cdev->def_manufacturer);
1534         kfree(cdev);
1535         set_gadget_data(gadget, NULL);
1536 }
1537
1538 static void composite_unbind(struct usb_gadget *gadget)
1539 {
1540         __composite_unbind(gadget, true);
1541 }
1542
1543 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1544                 const struct usb_device_descriptor *old)
1545 {
1546         __le16 idVendor;
1547         __le16 idProduct;
1548         __le16 bcdDevice;
1549         u8 iSerialNumber;
1550         u8 iManufacturer;
1551         u8 iProduct;
1552
1553         /*
1554          * these variables may have been set in
1555          * usb_composite_overwrite_options()
1556          */
1557         idVendor = new->idVendor;
1558         idProduct = new->idProduct;
1559         bcdDevice = new->bcdDevice;
1560         iSerialNumber = new->iSerialNumber;
1561         iManufacturer = new->iManufacturer;
1562         iProduct = new->iProduct;
1563
1564         *new = *old;
1565         if (idVendor)
1566                 new->idVendor = idVendor;
1567         if (idProduct)
1568                 new->idProduct = idProduct;
1569         if (bcdDevice)
1570                 new->bcdDevice = bcdDevice;
1571         else
1572                 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1573         if (iSerialNumber)
1574                 new->iSerialNumber = iSerialNumber;
1575         if (iManufacturer)
1576                 new->iManufacturer = iManufacturer;
1577         if (iProduct)
1578                 new->iProduct = iProduct;
1579 }
1580
1581 int composite_dev_prepare(struct usb_composite_driver *composite,
1582                 struct usb_composite_dev *cdev)
1583 {
1584         struct usb_gadget *gadget = cdev->gadget;
1585         int ret = -ENOMEM;
1586
1587         /* preallocate control response and buffer */
1588         cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1589         if (!cdev->req)
1590                 return -ENOMEM;
1591
1592         cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
1593         if (!cdev->req->buf)
1594                 goto fail;
1595
1596         ret = device_create_file(&gadget->dev, &dev_attr_suspended);
1597         if (ret)
1598                 goto fail_dev;
1599
1600         cdev->req->complete = composite_setup_complete;
1601         gadget->ep0->driver_data = cdev;
1602
1603         cdev->driver = composite;
1604
1605         /*
1606          * As per USB compliance update, a device that is actively drawing
1607          * more than 100mA from USB must report itself as bus-powered in
1608          * the GetStatus(DEVICE) call.
1609          */
1610         if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1611                 usb_gadget_set_selfpowered(gadget);
1612
1613         /* interface and string IDs start at zero via kzalloc.
1614          * we force endpoints to start unassigned; few controller
1615          * drivers will zero ep->driver_data.
1616          */
1617         usb_ep_autoconfig_reset(gadget);
1618         return 0;
1619 fail_dev:
1620         kfree(cdev->req->buf);
1621 fail:
1622         usb_ep_free_request(gadget->ep0, cdev->req);
1623         cdev->req = NULL;
1624         return ret;
1625 }
1626
1627 void composite_dev_cleanup(struct usb_composite_dev *cdev)
1628 {
1629         struct usb_gadget_string_container *uc, *tmp;
1630
1631         list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
1632                 list_del(&uc->list);
1633                 kfree(uc);
1634         }
1635         if (cdev->req) {
1636                 kfree(cdev->req->buf);
1637                 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
1638         }
1639         cdev->next_string_id = 0;
1640         device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
1641 }
1642
1643 static int composite_bind(struct usb_gadget *gadget,
1644                 struct usb_gadget_driver *gdriver)
1645 {
1646         struct usb_composite_dev        *cdev;
1647         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1648         int                             status = -ENOMEM;
1649
1650         cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1651         if (!cdev)
1652                 return status;
1653
1654         spin_lock_init(&cdev->lock);
1655         cdev->gadget = gadget;
1656         set_gadget_data(gadget, cdev);
1657         INIT_LIST_HEAD(&cdev->configs);
1658         INIT_LIST_HEAD(&cdev->gstrings);
1659
1660         status = composite_dev_prepare(composite, cdev);
1661         if (status)
1662                 goto fail;
1663
1664         /* composite gadget needs to assign strings for whole device (like
1665          * serial number), register function drivers, potentially update
1666          * power state and consumption, etc
1667          */
1668         status = composite->bind(cdev);
1669         if (status < 0)
1670                 goto fail;
1671
1672         update_unchanged_dev_desc(&cdev->desc, composite->dev);
1673
1674         /* has userspace failed to provide a serial number? */
1675         if (composite->needs_serial && !cdev->desc.iSerialNumber)
1676                 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1677
1678         INFO(cdev, "%s ready\n", composite->name);
1679         return 0;
1680
1681 fail:
1682         __composite_unbind(gadget, false);
1683         return status;
1684 }
1685
1686 /*-------------------------------------------------------------------------*/
1687
1688 static void
1689 composite_suspend(struct usb_gadget *gadget)
1690 {
1691         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1692         struct usb_function             *f;
1693
1694         /* REVISIT:  should we have config level
1695          * suspend/resume callbacks?
1696          */
1697         DBG(cdev, "suspend\n");
1698         if (cdev->config) {
1699                 list_for_each_entry(f, &cdev->config->functions, list) {
1700                         if (f->suspend)
1701                                 f->suspend(f);
1702                 }
1703         }
1704         if (cdev->driver->suspend)
1705                 cdev->driver->suspend(cdev);
1706
1707         cdev->suspended = 1;
1708
1709         usb_gadget_vbus_draw(gadget, 2);
1710 }
1711
1712 static void
1713 composite_resume(struct usb_gadget *gadget)
1714 {
1715         struct usb_composite_dev        *cdev = get_gadget_data(gadget);
1716         struct usb_function             *f;
1717         u8                              maxpower;
1718
1719         /* REVISIT:  should we have config level
1720          * suspend/resume callbacks?
1721          */
1722         DBG(cdev, "resume\n");
1723         if (cdev->driver->resume)
1724                 cdev->driver->resume(cdev);
1725         if (cdev->config) {
1726                 list_for_each_entry(f, &cdev->config->functions, list) {
1727                         if (f->resume)
1728                                 f->resume(f);
1729                 }
1730
1731                 maxpower = cdev->config->MaxPower;
1732
1733                 usb_gadget_vbus_draw(gadget, maxpower ?
1734                         maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
1735         }
1736
1737         cdev->suspended = 0;
1738 }
1739
1740 /*-------------------------------------------------------------------------*/
1741
1742 static const struct usb_gadget_driver composite_driver_template = {
1743         .bind           = composite_bind,
1744         .unbind         = composite_unbind,
1745
1746         .setup          = composite_setup,
1747         .disconnect     = composite_disconnect,
1748
1749         .suspend        = composite_suspend,
1750         .resume         = composite_resume,
1751
1752         .driver = {
1753                 .owner          = THIS_MODULE,
1754         },
1755 };
1756
1757 /**
1758  * usb_composite_probe() - register a composite driver
1759  * @driver: the driver to register
1760  *
1761  * Context: single threaded during gadget setup
1762  *
1763  * This function is used to register drivers using the composite driver
1764  * framework.  The return value is zero, or a negative errno value.
1765  * Those values normally come from the driver's @bind method, which does
1766  * all the work of setting up the driver to match the hardware.
1767  *
1768  * On successful return, the gadget is ready to respond to requests from
1769  * the host, unless one of its components invokes usb_gadget_disconnect()
1770  * while it was binding.  That would usually be done in order to wait for
1771  * some userspace participation.
1772  */
1773 int usb_composite_probe(struct usb_composite_driver *driver)
1774 {
1775         struct usb_gadget_driver *gadget_driver;
1776
1777         if (!driver || !driver->dev || !driver->bind)
1778                 return -EINVAL;
1779
1780         if (!driver->name)
1781                 driver->name = "composite";
1782
1783         driver->gadget_driver = composite_driver_template;
1784         gadget_driver = &driver->gadget_driver;
1785
1786         gadget_driver->function =  (char *) driver->name;
1787         gadget_driver->driver.name = driver->name;
1788         gadget_driver->max_speed = driver->max_speed;
1789
1790         return usb_gadget_probe_driver(gadget_driver);
1791 }
1792 EXPORT_SYMBOL_GPL(usb_composite_probe);
1793
1794 /**
1795  * usb_composite_unregister() - unregister a composite driver
1796  * @driver: the driver to unregister
1797  *
1798  * This function is used to unregister drivers using the composite
1799  * driver framework.
1800  */
1801 void usb_composite_unregister(struct usb_composite_driver *driver)
1802 {
1803         usb_gadget_unregister_driver(&driver->gadget_driver);
1804 }
1805 EXPORT_SYMBOL_GPL(usb_composite_unregister);
1806
1807 /**
1808  * usb_composite_setup_continue() - Continue with the control transfer
1809  * @cdev: the composite device who's control transfer was kept waiting
1810  *
1811  * This function must be called by the USB function driver to continue
1812  * with the control transfer's data/status stage in case it had requested to
1813  * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1814  * can request the composite framework to delay the setup request's data/status
1815  * stages by returning USB_GADGET_DELAYED_STATUS.
1816  */
1817 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1818 {
1819         int                     value;
1820         struct usb_request      *req = cdev->req;
1821         unsigned long           flags;
1822
1823         DBG(cdev, "%s\n", __func__);
1824         spin_lock_irqsave(&cdev->lock, flags);
1825
1826         if (cdev->delayed_status == 0) {
1827                 WARN(cdev, "%s: Unexpected call\n", __func__);
1828
1829         } else if (--cdev->delayed_status == 0) {
1830                 DBG(cdev, "%s: Completing delayed status\n", __func__);
1831                 req->length = 0;
1832                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1833                 if (value < 0) {
1834                         DBG(cdev, "ep_queue --> %d\n", value);
1835                         req->status = 0;
1836                         composite_setup_complete(cdev->gadget->ep0, req);
1837                 }
1838         }
1839
1840         spin_unlock_irqrestore(&cdev->lock, flags);
1841 }
1842 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
1843
1844 static char *composite_default_mfr(struct usb_gadget *gadget)
1845 {
1846         char *mfr;
1847         int len;
1848
1849         len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
1850                         init_utsname()->release, gadget->name);
1851         len++;
1852         mfr = kmalloc(len, GFP_KERNEL);
1853         if (!mfr)
1854                 return NULL;
1855         snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
1856                         init_utsname()->release, gadget->name);
1857         return mfr;
1858 }
1859
1860 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
1861                 struct usb_composite_overwrite *covr)
1862 {
1863         struct usb_device_descriptor    *desc = &cdev->desc;
1864         struct usb_gadget_strings       *gstr = cdev->driver->strings[0];
1865         struct usb_string               *dev_str = gstr->strings;
1866
1867         if (covr->idVendor)
1868                 desc->idVendor = cpu_to_le16(covr->idVendor);
1869
1870         if (covr->idProduct)
1871                 desc->idProduct = cpu_to_le16(covr->idProduct);
1872
1873         if (covr->bcdDevice)
1874                 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
1875
1876         if (covr->serial_number) {
1877                 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
1878                 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
1879         }
1880         if (covr->manufacturer) {
1881                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1882                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
1883
1884         } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
1885                 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1886                 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
1887                 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
1888         }
1889
1890         if (covr->product) {
1891                 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
1892                 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
1893         }
1894 }
1895 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
1896
1897 MODULE_LICENSE("GPL");
1898 MODULE_AUTHOR("David Brownell");