drivers/usb/core/config.c

   1 #include <linux/usb.h>
   2 #include <linux/usb/ch9.h>
   3 #include <linux/usb/hcd.h>
   4 #include <linux/usb/quirks.h>
   5 #include <linux/module.h>
   6 #include <linux/slab.h>
   7 #include <linux/device.h>
   8 #include <asm/byteorder.h>
   9 #include "usb.h"
  10
  11
  12 #define USB_MAXALTSETTING               128     /* Hard limit */
  13
  14 #define USB_MAXCONFIG                   8       /* Arbitrary limit */
  15
  16
  17 static inline const char *plural(int n)
  18 {
  19         return (n == 1 ? "" : "s");
  20 }
  21
  22 static int find_next_descriptor(unsigned char *buffer, int size,
  23     int dt1, int dt2, int *num_skipped)
  24 {
  25         struct usb_descriptor_header *h;
  26         int n = 0;
  27         unsigned char *buffer0 = buffer;
  28
  29         /* Find the next descriptor of type dt1 or dt2 */
  30         while (size > 0) {
  31                 h = (struct usb_descriptor_header *) buffer;
  32                 if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
  33                         break;
  34                 buffer += h->bLength;
  35                 size -= h->bLength;
  36                 ++n;
  37         }
  38
  39         /* Store the number of descriptors skipped and return the
  40          * number of bytes skipped */
  41         if (num_skipped)
  42                 *num_skipped = n;
  43         return buffer - buffer0;
  44 }
  45
  46 static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
  47                 int inum, int asnum, struct usb_host_endpoint *ep,
  48                 unsigned char *buffer, int size)
  49 {
  50         struct usb_ss_ep_comp_descriptor *desc;
  51         int max_tx;
  52
  53         /* The SuperSpeed endpoint companion descriptor is supposed to
  54          * be the first thing immediately following the endpoint descriptor.
  55          */
  56         desc = (struct usb_ss_ep_comp_descriptor *) buffer;
  57         if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
  58                         size < USB_DT_SS_EP_COMP_SIZE) {
  59                 dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
  60                                 " interface %d altsetting %d ep %d: "
  61                                 "using minimum values\n",
  62                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  63
  64                 /* Fill in some default values.
  65                  * Leave bmAttributes as zero, which will mean no streams for
  66                  * bulk, and isoc won't support multiple bursts of packets.
  67                  * With bursts of only one packet, and a Mult of 1, the max
  68                  * amount of data moved per endpoint service interval is one
  69                  * packet.
  70                  */
  71                 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
  72                 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
  73                 if (usb_endpoint_xfer_isoc(&ep->desc) ||
  74                                 usb_endpoint_xfer_int(&ep->desc))
  75                         ep->ss_ep_comp.wBytesPerInterval =
  76                                         ep->desc.wMaxPacketSize;
  77                 return;
  78         }
  79
  80         memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
  81
  82         /* Check the various values */
  83         if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
  84                 dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
  85                                 "config %d interface %d altsetting %d ep %d: "
  86                                 "setting to zero\n", desc->bMaxBurst,
  87                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  88                 ep->ss_ep_comp.bMaxBurst = 0;
  89         } else if (desc->bMaxBurst > 15) {
  90                 dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
  91                                 "config %d interface %d altsetting %d ep %d: "
  92                                 "setting to 15\n", desc->bMaxBurst,
  93                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  94                 ep->ss_ep_comp.bMaxBurst = 15;
  95         }
  96
  97         if ((usb_endpoint_xfer_control(&ep->desc) ||
  98                         usb_endpoint_xfer_int(&ep->desc)) &&
  99                                 desc->bmAttributes != 0) {
 100                 dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
 101                                 "config %d interface %d altsetting %d ep %d: "
 102                                 "setting to zero\n",
 103                                 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 104                                 desc->bmAttributes,
 105                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 106                 ep->ss_ep_comp.bmAttributes = 0;
 107         } else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 108                         desc->bmAttributes > 16) {
 109                 dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
 110                                 "config %d interface %d altsetting %d ep %d: "
 111                                 "setting to max\n",
 112                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 113                 ep->ss_ep_comp.bmAttributes = 16;
 114         } else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 115                         desc->bmAttributes > 2) {
 116                 dev_warn(ddev, "Isoc endpoint has Mult of %d in "
 117                                 "config %d interface %d altsetting %d ep %d: "
 118                                 "setting to 3\n", desc->bmAttributes + 1,
 119                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 120                 ep->ss_ep_comp.bmAttributes = 2;
 121         }
 122
 123         if (usb_endpoint_xfer_isoc(&ep->desc))
 124                 max_tx = (desc->bMaxBurst + 1) * (desc->bmAttributes + 1) *
 125                         usb_endpoint_maxp(&ep->desc);
 126         else if (usb_endpoint_xfer_int(&ep->desc))
 127                 max_tx = usb_endpoint_maxp(&ep->desc) *
 128                         (desc->bMaxBurst + 1);
 129         else
 130                 max_tx = 999999;
 131         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 132                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 133                                 "config %d interface %d altsetting %d ep %d: "
 134                                 "setting to %d\n",
 135                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 136                                 le16_to_cpu(desc->wBytesPerInterval),
 137                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 138                                 max_tx);
 139                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 140         }
 141 }
 142
 143 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 144     int asnum, struct usb_host_interface *ifp, int num_ep,
 145     unsigned char *buffer, int size)
 146 {
 147         unsigned char *buffer0 = buffer;
 148         struct usb_endpoint_descriptor *d;
 149         struct usb_host_endpoint *endpoint;
 150         int n, i, j, retval;
 151
 152         d = (struct usb_endpoint_descriptor *) buffer;
 153         buffer += d->bLength;
 154         size -= d->bLength;
 155
 156         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 157                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 158         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 159                 n = USB_DT_ENDPOINT_SIZE;
 160         else {
 161                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 162                     "invalid endpoint descriptor of length %d, skipping\n",
 163                     cfgno, inum, asnum, d->bLength);
 164                 goto skip_to_next_endpoint_or_interface_descriptor;
 165         }
 166
 167         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 168         if (i >= 16 || i == 0) {
 169                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 170                     "invalid endpoint with address 0x%X, skipping\n",
 171                     cfgno, inum, asnum, d->bEndpointAddress);
 172                 goto skip_to_next_endpoint_or_interface_descriptor;
 173         }
 174
 175         /* Only store as many endpoints as we have room for */
 176         if (ifp->desc.bNumEndpoints >= num_ep)
 177                 goto skip_to_next_endpoint_or_interface_descriptor;
 178
 179         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 180         ++ifp->desc.bNumEndpoints;
 181
 182         memcpy(&endpoint->desc, d, n);
 183         INIT_LIST_HEAD(&endpoint->urb_list);
 184
 185         /* Fix up bInterval values outside the legal range. Use 32 ms if no
 186          * proper value can be guessed. */
 187         i = 0;          /* i = min, j = max, n = default */
 188         j = 255;
 189         if (usb_endpoint_xfer_int(d)) {
 190                 i = 1;
 191                 switch (to_usb_device(ddev)->speed) {
 192                 case USB_SPEED_SUPER:
 193                 case USB_SPEED_HIGH:
 194                         /* Many device manufacturers are using full-speed
 195                          * bInterval values in high-speed interrupt endpoint
 196                          * descriptors. Try to fix those and fall back to a
 197                          * 32 ms default value otherwise. */
 198                         n = fls(d->bInterval*8);
 199                         if (n == 0)
 200                                 n = 9;  /* 32 ms = 2^(9-1) uframes */
 201                         j = 16;
 202
 203                         /*
 204                          * Adjust bInterval for quirked devices.
 205                          * This quirk fixes bIntervals reported in
 206                          * linear microframes.
 207                          */
 208                         if (to_usb_device(ddev)->quirks &
 209                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 210                                 n = clamp(fls(d->bInterval), i, j);
 211                                 i = j = n;
 212                         }
 213                         break;
 214                 default:                /* USB_SPEED_FULL or _LOW */
 215                         /* For low-speed, 10 ms is the official minimum.
 216                          * But some "overclocked" devices might want faster
 217                          * polling so we'll allow it. */
 218                         n = 32;
 219                         break;
 220                 }
 221         } else if (usb_endpoint_xfer_isoc(d)) {
 222                 i = 1;
 223                 j = 16;
 224                 switch (to_usb_device(ddev)->speed) {
 225                 case USB_SPEED_HIGH:
 226                         n = 9;          /* 32 ms = 2^(9-1) uframes */
 227                         break;
 228                 default:                /* USB_SPEED_FULL */
 229                         n = 6;          /* 32 ms = 2^(6-1) frames */
 230                         break;
 231                 }
 232         }
 233         if (d->bInterval < i || d->bInterval > j) {
 234                 dev_warn(ddev, "config %d interface %d altsetting %d "
 235                     "endpoint 0x%X has an invalid bInterval %d, "
 236                     "changing to %d\n",
 237                     cfgno, inum, asnum,
 238                     d->bEndpointAddress, d->bInterval, n);
 239                 endpoint->desc.bInterval = n;
 240         }
 241
 242         /* Some buggy low-speed devices have Bulk endpoints, which is
 243          * explicitly forbidden by the USB spec.  In an attempt to make
 244          * them usable, we will try treating them as Interrupt endpoints.
 245          */
 246         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 247                         usb_endpoint_xfer_bulk(d)) {
 248                 dev_warn(ddev, "config %d interface %d altsetting %d "
 249                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 250                     cfgno, inum, asnum, d->bEndpointAddress);
 251                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 252                 endpoint->desc.bInterval = 1;
 253                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 254                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 255         }
 256
 257         /*
 258          * Some buggy high speed devices have bulk endpoints using
 259          * maxpacket sizes other than 512.  High speed HCDs may not
 260          * be able to handle that particular bug, so let's warn...
 261          */
 262         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 263                         && usb_endpoint_xfer_bulk(d)) {
 264                 unsigned maxp;
 265
 266                 maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
 267                 if (maxp != 512)
 268                         dev_warn(ddev, "config %d interface %d altsetting %d "
 269                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 270                                 cfgno, inum, asnum, d->bEndpointAddress,
 271                                 maxp);
 272         }
 273
 274         /* Parse a possible SuperSpeed endpoint companion descriptor */
 275         if (to_usb_device(ddev)->speed == USB_SPEED_SUPER)
 276                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 277                                 inum, asnum, endpoint, buffer, size);
 278
 279         /* Skip over any Class Specific or Vendor Specific descriptors;
 280          * find the next endpoint or interface descriptor */
 281         endpoint->extra = buffer;
 282         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 283                         USB_DT_INTERFACE, &n);
 284         endpoint->extralen = i;
 285         retval = buffer - buffer0 + i;
 286         if (n > 0)
 287                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 288                     n, plural(n), "endpoint");
 289         return retval;
 290
 291 skip_to_next_endpoint_or_interface_descriptor:
 292         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 293             USB_DT_INTERFACE, NULL);
 294         return buffer - buffer0 + i;
 295 }
 296
 297 void usb_release_interface_cache(struct kref *ref)
 298 {
 299         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 300         int j;
 301
 302         for (j = 0; j < intfc->num_altsetting; j++) {
 303                 struct usb_host_interface *alt = &intfc->altsetting[j];
 304
 305                 kfree(alt->endpoint);
 306                 kfree(alt->string);
 307         }
 308         kfree(intfc);
 309 }
 310
 311 static int usb_parse_interface(struct device *ddev, int cfgno,
 312     struct usb_host_config *config, unsigned char *buffer, int size,
 313     u8 inums[], u8 nalts[])
 314 {
 315         unsigned char *buffer0 = buffer;
 316         struct usb_interface_descriptor *d;
 317         int inum, asnum;
 318         struct usb_interface_cache *intfc;
 319         struct usb_host_interface *alt;
 320         int i, n;
 321         int len, retval;
 322         int num_ep, num_ep_orig;
 323
 324         d = (struct usb_interface_descriptor *) buffer;
 325         buffer += d->bLength;
 326         size -= d->bLength;
 327
 328         if (d->bLength < USB_DT_INTERFACE_SIZE)
 329                 goto skip_to_next_interface_descriptor;
 330
 331         /* Which interface entry is this? */
 332         intfc = NULL;
 333         inum = d->bInterfaceNumber;
 334         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 335                 if (inums[i] == inum) {
 336                         intfc = config->intf_cache[i];
 337                         break;
 338                 }
 339         }
 340         if (!intfc || intfc->num_altsetting >= nalts[i])
 341                 goto skip_to_next_interface_descriptor;
 342
 343         /* Check for duplicate altsetting entries */
 344         asnum = d->bAlternateSetting;
 345         for ((i = 0, alt = &intfc->altsetting[0]);
 346               i < intfc->num_altsetting;
 347              (++i, ++alt)) {
 348                 if (alt->desc.bAlternateSetting == asnum) {
 349                         dev_warn(ddev, "Duplicate descriptor for config %d "
 350                             "interface %d altsetting %d, skipping\n",
 351                             cfgno, inum, asnum);
 352                         goto skip_to_next_interface_descriptor;
 353                 }
 354         }
 355
 356         ++intfc->num_altsetting;
 357         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 358
 359         /* Skip over any Class Specific or Vendor Specific descriptors;
 360          * find the first endpoint or interface descriptor */
 361         alt->extra = buffer;
 362         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 363             USB_DT_INTERFACE, &n);
 364         alt->extralen = i;
 365         if (n > 0)
 366                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 367                     n, plural(n), "interface");
 368         buffer += i;
 369         size -= i;
 370
 371         /* Allocate space for the right(?) number of endpoints */
 372         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 373         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 374         if (num_ep > USB_MAXENDPOINTS) {
 375                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 376                     "altsetting %d: %d, using maximum allowed: %d\n",
 377                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 378                 num_ep = USB_MAXENDPOINTS;
 379         }
 380
 381         if (num_ep > 0) {
 382                 /* Can't allocate 0 bytes */
 383                 len = sizeof(struct usb_host_endpoint) * num_ep;
 384                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 385                 if (!alt->endpoint)
 386                         return -ENOMEM;
 387         }
 388
 389         /* Parse all the endpoint descriptors */
 390         n = 0;
 391         while (size > 0) {
 392                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 393                      == USB_DT_INTERFACE)
 394                         break;
 395                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 396                     num_ep, buffer, size);
 397                 if (retval < 0)
 398                         return retval;
 399                 ++n;
 400
 401                 buffer += retval;
 402                 size -= retval;
 403         }
 404
 405         if (n != num_ep_orig)
 406                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 407                     "endpoint descriptor%s, different from the interface "
 408                     "descriptor's value: %d\n",
 409                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 410         return buffer - buffer0;
 411
 412 skip_to_next_interface_descriptor:
 413         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 414             USB_DT_INTERFACE, NULL);
 415         return buffer - buffer0 + i;
 416 }
 417
 418 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 419     struct usb_host_config *config, unsigned char *buffer, int size)
 420 {
 421         struct device *ddev = &dev->dev;
 422         unsigned char *buffer0 = buffer;
 423         int cfgno;
 424         int nintf, nintf_orig;
 425         int i, j, n;
 426         struct usb_interface_cache *intfc;
 427         unsigned char *buffer2;
 428         int size2;
 429         struct usb_descriptor_header *header;
 430         int len, retval;
 431         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 432         unsigned iad_num = 0;
 433
 434         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 435         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 436             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 437             config->desc.bLength > size) {
 438                 dev_err(ddev, "invalid descriptor for config index %d: "
 439                     "type = 0x%X, length = %d\n", cfgidx,
 440                     config->desc.bDescriptorType, config->desc.bLength);
 441                 return -EINVAL;
 442         }
 443         cfgno = config->desc.bConfigurationValue;
 444
 445         buffer += config->desc.bLength;
 446         size -= config->desc.bLength;
 447
 448         nintf = nintf_orig = config->desc.bNumInterfaces;
 449         if (nintf > USB_MAXINTERFACES) {
 450                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 451                     "using maximum allowed: %d\n",
 452                     cfgno, nintf, USB_MAXINTERFACES);
 453                 nintf = USB_MAXINTERFACES;
 454         }
 455
 456         /* Go through the descriptors, checking their length and counting the
 457          * number of altsettings for each interface */
 458         n = 0;
 459         for ((buffer2 = buffer, size2 = size);
 460               size2 > 0;
 461              (buffer2 += header->bLength, size2 -= header->bLength)) {
 462
 463                 if (size2 < sizeof(struct usb_descriptor_header)) {
 464                         dev_warn(ddev, "config %d descriptor has %d excess "
 465                             "byte%s, ignoring\n",
 466                             cfgno, size2, plural(size2));
 467                         break;
 468                 }
 469
 470                 header = (struct usb_descriptor_header *) buffer2;
 471                 if ((header->bLength > size2) || (header->bLength < 2)) {
 472                         dev_warn(ddev, "config %d has an invalid descriptor "
 473                             "of length %d, skipping remainder of the config\n",
 474                             cfgno, header->bLength);
 475                         break;
 476                 }
 477
 478                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 479                         struct usb_interface_descriptor *d;
 480                         int inum;
 481
 482                         d = (struct usb_interface_descriptor *) header;
 483                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 484                                 dev_warn(ddev, "config %d has an invalid "
 485                                     "interface descriptor of length %d, "
 486                                     "skipping\n", cfgno, d->bLength);
 487                                 continue;
 488                         }
 489
 490                         inum = d->bInterfaceNumber;
 491
 492                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 493                             n >= nintf_orig) {
 494                                 dev_warn(ddev, "config %d has more interface "
 495                                     "descriptors, than it declares in "
 496                                     "bNumInterfaces, ignoring interface "
 497                                     "number: %d\n", cfgno, inum);
 498                                 continue;
 499                         }
 500
 501                         if (inum >= nintf_orig)
 502                                 dev_warn(ddev, "config %d has an invalid "
 503                                     "interface number: %d but max is %d\n",
 504                                     cfgno, inum, nintf_orig - 1);
 505
 506                         /* Have we already encountered this interface?
 507                          * Count its altsettings */
 508                         for (i = 0; i < n; ++i) {
 509                                 if (inums[i] == inum)
 510                                         break;
 511                         }
 512                         if (i < n) {
 513                                 if (nalts[i] < 255)
 514                                         ++nalts[i];
 515                         } else if (n < USB_MAXINTERFACES) {
 516                                 inums[n] = inum;
 517                                 nalts[n] = 1;
 518                                 ++n;
 519                         }
 520
 521                 } else if (header->bDescriptorType ==
 522                                 USB_DT_INTERFACE_ASSOCIATION) {
 523                         if (iad_num == USB_MAXIADS) {
 524                                 dev_warn(ddev, "found more Interface "
 525                                                "Association Descriptors "
 526                                                "than allocated for in "
 527                                                "configuration %d\n", cfgno);
 528                         } else {
 529                                 config->intf_assoc[iad_num] =
 530                                         (struct usb_interface_assoc_descriptor
 531                                         *)header;
 532                                 iad_num++;
 533                         }
 534
 535                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 536                             header->bDescriptorType == USB_DT_CONFIG)
 537                         dev_warn(ddev, "config %d contains an unexpected "
 538                             "descriptor of type 0x%X, skipping\n",
 539                             cfgno, header->bDescriptorType);
 540
 541         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 542         size = buffer2 - buffer;
 543         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 544
 545         if (n != nintf)
 546                 dev_warn(ddev, "config %d has %d interface%s, different from "
 547                     "the descriptor's value: %d\n",
 548                     cfgno, n, plural(n), nintf_orig);
 549         else if (n == 0)
 550                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 551         config->desc.bNumInterfaces = nintf = n;
 552
 553         /* Check for missing interface numbers */
 554         for (i = 0; i < nintf; ++i) {
 555                 for (j = 0; j < nintf; ++j) {
 556                         if (inums[j] == i)
 557                                 break;
 558                 }
 559                 if (j >= nintf)
 560                         dev_warn(ddev, "config %d has no interface number "
 561                             "%d\n", cfgno, i);
 562         }
 563
 564         /* Allocate the usb_interface_caches and altsetting arrays */
 565         for (i = 0; i < nintf; ++i) {
 566                 j = nalts[i];
 567                 if (j > USB_MAXALTSETTING) {
 568                         dev_warn(ddev, "too many alternate settings for "
 569                             "config %d interface %d: %d, "
 570                             "using maximum allowed: %d\n",
 571                             cfgno, inums[i], j, USB_MAXALTSETTING);
 572                         nalts[i] = j = USB_MAXALTSETTING;
 573                 }
 574
 575                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 576                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 577                 if (!intfc)
 578                         return -ENOMEM;
 579                 kref_init(&intfc->ref);
 580         }
 581
 582         /* FIXME: parse the BOS descriptor */
 583
 584         /* Skip over any Class Specific or Vendor Specific descriptors;
 585          * find the first interface descriptor */
 586         config->extra = buffer;
 587         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 588             USB_DT_INTERFACE, &n);
 589         config->extralen = i;
 590         if (n > 0)
 591                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 592                     n, plural(n), "configuration");
 593         buffer += i;
 594         size -= i;
 595
 596         /* Parse all the interface/altsetting descriptors */
 597         while (size > 0) {
 598                 retval = usb_parse_interface(ddev, cfgno, config,
 599                     buffer, size, inums, nalts);
 600                 if (retval < 0)
 601                         return retval;
 602
 603                 buffer += retval;
 604                 size -= retval;
 605         }
 606
 607         /* Check for missing altsettings */
 608         for (i = 0; i < nintf; ++i) {
 609                 intfc = config->intf_cache[i];
 610                 for (j = 0; j < intfc->num_altsetting; ++j) {
 611                         for (n = 0; n < intfc->num_altsetting; ++n) {
 612                                 if (intfc->altsetting[n].desc.
 613                                     bAlternateSetting == j)
 614                                         break;
 615                         }
 616                         if (n >= intfc->num_altsetting)
 617                                 dev_warn(ddev, "config %d interface %d has no "
 618                                     "altsetting %d\n", cfgno, inums[i], j);
 619                 }
 620         }
 621
 622         return 0;
 623 }
 624
 625 /* hub-only!! ... and only exported for reset/reinit path.
 626  * otherwise used internally on disconnect/destroy path
 627  */
 628 void usb_destroy_configuration(struct usb_device *dev)
 629 {
 630         int c, i;
 631
 632         if (!dev->config)
 633                 return;
 634
 635         if (dev->rawdescriptors) {
 636                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 637                         kfree(dev->rawdescriptors[i]);
 638
 639                 kfree(dev->rawdescriptors);
 640                 dev->rawdescriptors = NULL;
 641         }
 642
 643         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 644                 struct usb_host_config *cf = &dev->config[c];
 645
 646                 kfree(cf->string);
 647                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 648                         if (cf->intf_cache[i])
 649                                 kref_put(&cf->intf_cache[i]->ref,
 650                                           usb_release_interface_cache);
 651                 }
 652         }
 653         kfree(dev->config);
 654         dev->config = NULL;
 655 }
 656
 657
 658 /*
 659  * Get the USB config descriptors, cache and parse'em
 660  *
 661  * hub-only!! ... and only in reset path, or usb_new_device()
 662  * (used by real hubs and virtual root hubs)
 663  */
 664 int usb_get_configuration(struct usb_device *dev)
 665 {
 666         struct device *ddev = &dev->dev;
 667         int ncfg = dev->descriptor.bNumConfigurations;
 668         int result = 0;
 669         unsigned int cfgno, length;
 670         unsigned char *bigbuffer;
 671         struct usb_config_descriptor *desc;
 672
 673         cfgno = 0;
 674         result = -ENOMEM;
 675         if (ncfg > USB_MAXCONFIG) {
 676                 dev_warn(ddev, "too many configurations: %d, "
 677                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 678                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 679         }
 680
 681         if (ncfg < 1) {
 682                 dev_err(ddev, "no configurations\n");
 683                 return -EINVAL;
 684         }
 685
 686         length = ncfg * sizeof(struct usb_host_config);
 687         dev->config = kzalloc(length, GFP_KERNEL);
 688         if (!dev->config)
 689                 goto err2;
 690
 691         length = ncfg * sizeof(char *);
 692         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 693         if (!dev->rawdescriptors)
 694                 goto err2;
 695
 696         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 697         if (!desc)
 698                 goto err2;
 699
 700         result = 0;
 701         for (; cfgno < ncfg; cfgno++) {
 702                 /* We grab just the first descriptor so we know how long
 703                  * the whole configuration is */
 704                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 705                     desc, USB_DT_CONFIG_SIZE);
 706                 if (result < 0) {
 707                         dev_err(ddev, "unable to read config index %d "
 708                             "descriptor/%s: %d\n", cfgno, "start", result);
 709                         if (result != -EPIPE)
 710                                 goto err;
 711                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 712                         dev->descriptor.bNumConfigurations = cfgno;
 713                         break;
 714                 } else if (result < 4) {
 715                         dev_err(ddev, "config index %d descriptor too short "
 716                             "(expected %i, got %i)\n", cfgno,
 717                             USB_DT_CONFIG_SIZE, result);
 718                         result = -EINVAL;
 719                         goto err;
 720                 }
 721                 length = max((int) le16_to_cpu(desc->wTotalLength),
 722                     USB_DT_CONFIG_SIZE);
 723
 724                 /* Now that we know the length, get the whole thing */
 725                 bigbuffer = kmalloc(length, GFP_KERNEL);
 726                 if (!bigbuffer) {
 727                         result = -ENOMEM;
 728                         goto err;
 729                 }
 730
 731                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 732                         msleep(100);
 733
 734                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 735                     bigbuffer, length);
 736                 if (result < 0) {
 737                         dev_err(ddev, "unable to read config index %d "
 738                             "descriptor/%s\n", cfgno, "all");
 739                         kfree(bigbuffer);
 740                         goto err;
 741                 }
 742                 if (result < length) {
 743                         dev_warn(ddev, "config index %d descriptor too short "
 744                             "(expected %i, got %i)\n", cfgno, length, result);
 745                         length = result;
 746                 }
 747
 748                 dev->rawdescriptors[cfgno] = bigbuffer;
 749
 750                 result = usb_parse_configuration(dev, cfgno,
 751                     &dev->config[cfgno], bigbuffer, length);
 752                 if (result < 0) {
 753                         ++cfgno;
 754                         goto err;
 755                 }
 756         }
 757         result = 0;
 758
 759 err:
 760         kfree(desc);
 761         dev->descriptor.bNumConfigurations = cfgno;
 762 err2:
 763         if (result == -ENOMEM)
 764                 dev_err(ddev, "out of memory\n");
 765         return result;
 766 }
 767
 768 void usb_release_bos_descriptor(struct usb_device *dev)
 769 {
 770         if (dev->bos) {
 771                 kfree(dev->bos->desc);
 772                 kfree(dev->bos);
 773                 dev->bos = NULL;
 774         }
 775 }
 776
 777 /* Get BOS descriptor set */
 778 int usb_get_bos_descriptor(struct usb_device *dev)
 779 {
 780         struct device *ddev = &dev->dev;
 781         struct usb_bos_descriptor *bos;
 782         struct usb_dev_cap_header *cap;
 783         unsigned char *buffer;
 784         int length, total_len, num, i;
 785         int ret;
 786
 787         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 788         if (!bos)
 789                 return -ENOMEM;
 790
 791         /* Get BOS descriptor */
 792         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 793         if (ret < USB_DT_BOS_SIZE) {
 794                 dev_err(ddev, "unable to get BOS descriptor\n");
 795                 if (ret >= 0)
 796                         ret = -ENOMSG;
 797                 kfree(bos);
 798                 return ret;
 799         }
 800
 801         length = bos->bLength;
 802         total_len = le16_to_cpu(bos->wTotalLength);
 803         num = bos->bNumDeviceCaps;
 804         kfree(bos);
 805         if (total_len < length)
 806                 return -EINVAL;
 807
 808         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 809         if (!dev->bos)
 810                 return -ENOMEM;
 811
 812         /* Now let's get the whole BOS descriptor set */
 813         buffer = kzalloc(total_len, GFP_KERNEL);
 814         if (!buffer) {
 815                 ret = -ENOMEM;
 816                 goto err;
 817         }
 818         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 819
 820         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 821         if (ret < total_len) {
 822                 dev_err(ddev, "unable to get BOS descriptor set\n");
 823                 if (ret >= 0)
 824                         ret = -ENOMSG;
 825                 goto err;
 826         }
 827         total_len -= length;
 828
 829         for (i = 0; i < num; i++) {
 830                 buffer += length;
 831                 cap = (struct usb_dev_cap_header *)buffer;
 832                 length = cap->bLength;
 833
 834                 if (total_len < length)
 835                         break;
 836                 total_len -= length;
 837
 838                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 839                         dev_warn(ddev, "descriptor type invalid, skip\n");
 840                         continue;
 841                 }
 842
 843                 switch (cap->bDevCapabilityType) {
 844                 case USB_CAP_TYPE_WIRELESS_USB:
 845                         /* Wireless USB cap descriptor is handled by wusb */
 846                         break;
 847                 case USB_CAP_TYPE_EXT:
 848                         dev->bos->ext_cap =
 849                                 (struct usb_ext_cap_descriptor *)buffer;
 850                         break;
 851                 case USB_SS_CAP_TYPE:
 852                         dev->bos->ss_cap =
 853                                 (struct usb_ss_cap_descriptor *)buffer;
 854                         break;
 855                 case CONTAINER_ID_TYPE:
 856                         dev->bos->ss_id =
 857                                 (struct usb_ss_container_id_descriptor *)buffer;
 858                         break;
 859                 default:
 860                         break;
 861                 }
 862         }
 863
 864         return 0;
 865
 866 err:
 867         usb_release_bos_descriptor(dev);
 868         return ret;
 869 }