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                    USB_SS_MULT(desc->bmAttributes) > 3) {
 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",
 119                                 USB_SS_MULT(desc->bmAttributes),
 120                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 121                 ep->ss_ep_comp.bmAttributes = 2;
 122         }
 123
 124         if (usb_endpoint_xfer_isoc(&ep->desc))
 125                 max_tx = (desc->bMaxBurst + 1) *
 126                         (USB_SS_MULT(desc->bmAttributes)) *
 127                         usb_endpoint_maxp(&ep->desc);
 128         else if (usb_endpoint_xfer_int(&ep->desc))
 129                 max_tx = usb_endpoint_maxp(&ep->desc) *
 130                         (desc->bMaxBurst + 1);
 131         else
 132                 max_tx = 999999;
 133         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 134                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 135                                 "config %d interface %d altsetting %d ep %d: "
 136                                 "setting to %d\n",
 137                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 138                                 le16_to_cpu(desc->wBytesPerInterval),
 139                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 140                                 max_tx);
 141                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 142         }
 143 }
 144
 145 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 146     int asnum, struct usb_host_interface *ifp, int num_ep,
 147     unsigned char *buffer, int size)
 148 {
 149         unsigned char *buffer0 = buffer;
 150         struct usb_endpoint_descriptor *d;
 151         struct usb_host_endpoint *endpoint;
 152         int n, i, j, retval;
 153
 154         d = (struct usb_endpoint_descriptor *) buffer;
 155         buffer += d->bLength;
 156         size -= d->bLength;
 157
 158         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 159                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 160         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 161                 n = USB_DT_ENDPOINT_SIZE;
 162         else {
 163                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 164                     "invalid endpoint descriptor of length %d, skipping\n",
 165                     cfgno, inum, asnum, d->bLength);
 166                 goto skip_to_next_endpoint_or_interface_descriptor;
 167         }
 168
 169         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 170         if (i >= 16 || i == 0) {
 171                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 172                     "invalid endpoint with address 0x%X, skipping\n",
 173                     cfgno, inum, asnum, d->bEndpointAddress);
 174                 goto skip_to_next_endpoint_or_interface_descriptor;
 175         }
 176
 177         /* Only store as many endpoints as we have room for */
 178         if (ifp->desc.bNumEndpoints >= num_ep)
 179                 goto skip_to_next_endpoint_or_interface_descriptor;
 180
 181         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 182         ++ifp->desc.bNumEndpoints;
 183
 184         memcpy(&endpoint->desc, d, n);
 185         INIT_LIST_HEAD(&endpoint->urb_list);
 186
 187         /* Fix up bInterval values outside the legal range. Use 32 ms if no
 188          * proper value can be guessed. */
 189         i = 0;          /* i = min, j = max, n = default */
 190         j = 255;
 191         if (usb_endpoint_xfer_int(d)) {
 192                 i = 1;
 193                 switch (to_usb_device(ddev)->speed) {
 194                 case USB_SPEED_SUPER_PLUS:
 195                 case USB_SPEED_SUPER:
 196                 case USB_SPEED_HIGH:
 197                         /* Many device manufacturers are using full-speed
 198                          * bInterval values in high-speed interrupt endpoint
 199                          * descriptors. Try to fix those and fall back to a
 200                          * 32 ms default value otherwise. */
 201                         n = fls(d->bInterval*8);
 202                         if (n == 0)
 203                                 n = 9;  /* 32 ms = 2^(9-1) uframes */
 204                         j = 16;
 205
 206                         /*
 207                          * Adjust bInterval for quirked devices.
 208                          * This quirk fixes bIntervals reported in
 209                          * linear microframes.
 210                          */
 211                         if (to_usb_device(ddev)->quirks &
 212                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 213                                 n = clamp(fls(d->bInterval), i, j);
 214                                 i = j = n;
 215                         }
 216                         break;
 217                 default:                /* USB_SPEED_FULL or _LOW */
 218                         /* For low-speed, 10 ms is the official minimum.
 219                          * But some "overclocked" devices might want faster
 220                          * polling so we'll allow it. */
 221                         n = 32;
 222                         break;
 223                 }
 224         } else if (usb_endpoint_xfer_isoc(d)) {
 225                 i = 1;
 226                 j = 16;
 227                 switch (to_usb_device(ddev)->speed) {
 228                 case USB_SPEED_HIGH:
 229                         n = 9;          /* 32 ms = 2^(9-1) uframes */
 230                         break;
 231                 default:                /* USB_SPEED_FULL */
 232                         n = 6;          /* 32 ms = 2^(6-1) frames */
 233                         break;
 234                 }
 235         }
 236         if (d->bInterval < i || d->bInterval > j) {
 237                 dev_warn(ddev, "config %d interface %d altsetting %d "
 238                     "endpoint 0x%X has an invalid bInterval %d, "
 239                     "changing to %d\n",
 240                     cfgno, inum, asnum,
 241                     d->bEndpointAddress, d->bInterval, n);
 242                 endpoint->desc.bInterval = n;
 243         }
 244
 245         /* Some buggy low-speed devices have Bulk endpoints, which is
 246          * explicitly forbidden by the USB spec.  In an attempt to make
 247          * them usable, we will try treating them as Interrupt endpoints.
 248          */
 249         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 250                         usb_endpoint_xfer_bulk(d)) {
 251                 dev_warn(ddev, "config %d interface %d altsetting %d "
 252                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 253                     cfgno, inum, asnum, d->bEndpointAddress);
 254                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 255                 endpoint->desc.bInterval = 1;
 256                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 257                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 258         }
 259
 260         /*
 261          * Some buggy high speed devices have bulk endpoints using
 262          * maxpacket sizes other than 512.  High speed HCDs may not
 263          * be able to handle that particular bug, so let's warn...
 264          */
 265         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 266                         && usb_endpoint_xfer_bulk(d)) {
 267                 unsigned maxp;
 268
 269                 maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
 270                 if (maxp != 512)
 271                         dev_warn(ddev, "config %d interface %d altsetting %d "
 272                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 273                                 cfgno, inum, asnum, d->bEndpointAddress,
 274                                 maxp);
 275         }
 276
 277         /* Parse a possible SuperSpeed endpoint companion descriptor */
 278         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 279                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 280                                 inum, asnum, endpoint, buffer, size);
 281
 282         /* Skip over any Class Specific or Vendor Specific descriptors;
 283          * find the next endpoint or interface descriptor */
 284         endpoint->extra = buffer;
 285         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 286                         USB_DT_INTERFACE, &n);
 287         endpoint->extralen = i;
 288         retval = buffer - buffer0 + i;
 289         if (n > 0)
 290                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 291                     n, plural(n), "endpoint");
 292         return retval;
 293
 294 skip_to_next_endpoint_or_interface_descriptor:
 295         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 296             USB_DT_INTERFACE, NULL);
 297         return buffer - buffer0 + i;
 298 }
 299
 300 void usb_release_interface_cache(struct kref *ref)
 301 {
 302         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 303         int j;
 304
 305         for (j = 0; j < intfc->num_altsetting; j++) {
 306                 struct usb_host_interface *alt = &intfc->altsetting[j];
 307
 308                 kfree(alt->endpoint);
 309                 kfree(alt->string);
 310         }
 311         kfree(intfc);
 312 }
 313
 314 static int usb_parse_interface(struct device *ddev, int cfgno,
 315     struct usb_host_config *config, unsigned char *buffer, int size,
 316     u8 inums[], u8 nalts[])
 317 {
 318         unsigned char *buffer0 = buffer;
 319         struct usb_interface_descriptor *d;
 320         int inum, asnum;
 321         struct usb_interface_cache *intfc;
 322         struct usb_host_interface *alt;
 323         int i, n;
 324         int len, retval;
 325         int num_ep, num_ep_orig;
 326
 327         d = (struct usb_interface_descriptor *) buffer;
 328         buffer += d->bLength;
 329         size -= d->bLength;
 330
 331         if (d->bLength < USB_DT_INTERFACE_SIZE)
 332                 goto skip_to_next_interface_descriptor;
 333
 334         /* Which interface entry is this? */
 335         intfc = NULL;
 336         inum = d->bInterfaceNumber;
 337         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 338                 if (inums[i] == inum) {
 339                         intfc = config->intf_cache[i];
 340                         break;
 341                 }
 342         }
 343         if (!intfc || intfc->num_altsetting >= nalts[i])
 344                 goto skip_to_next_interface_descriptor;
 345
 346         /* Check for duplicate altsetting entries */
 347         asnum = d->bAlternateSetting;
 348         for ((i = 0, alt = &intfc->altsetting[0]);
 349               i < intfc->num_altsetting;
 350              (++i, ++alt)) {
 351                 if (alt->desc.bAlternateSetting == asnum) {
 352                         dev_warn(ddev, "Duplicate descriptor for config %d "
 353                             "interface %d altsetting %d, skipping\n",
 354                             cfgno, inum, asnum);
 355                         goto skip_to_next_interface_descriptor;
 356                 }
 357         }
 358
 359         ++intfc->num_altsetting;
 360         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 361
 362         /* Skip over any Class Specific or Vendor Specific descriptors;
 363          * find the first endpoint or interface descriptor */
 364         alt->extra = buffer;
 365         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 366             USB_DT_INTERFACE, &n);
 367         alt->extralen = i;
 368         if (n > 0)
 369                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 370                     n, plural(n), "interface");
 371         buffer += i;
 372         size -= i;
 373
 374         /* Allocate space for the right(?) number of endpoints */
 375         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 376         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 377         if (num_ep > USB_MAXENDPOINTS) {
 378                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 379                     "altsetting %d: %d, using maximum allowed: %d\n",
 380                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 381                 num_ep = USB_MAXENDPOINTS;
 382         }
 383
 384         if (num_ep > 0) {
 385                 /* Can't allocate 0 bytes */
 386                 len = sizeof(struct usb_host_endpoint) * num_ep;
 387                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 388                 if (!alt->endpoint)
 389                         return -ENOMEM;
 390         }
 391
 392         /* Parse all the endpoint descriptors */
 393         n = 0;
 394         while (size > 0) {
 395                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 396                      == USB_DT_INTERFACE)
 397                         break;
 398                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 399                     num_ep, buffer, size);
 400                 if (retval < 0)
 401                         return retval;
 402                 ++n;
 403
 404                 buffer += retval;
 405                 size -= retval;
 406         }
 407
 408         if (n != num_ep_orig)
 409                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 410                     "endpoint descriptor%s, different from the interface "
 411                     "descriptor's value: %d\n",
 412                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 413         return buffer - buffer0;
 414
 415 skip_to_next_interface_descriptor:
 416         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 417             USB_DT_INTERFACE, NULL);
 418         return buffer - buffer0 + i;
 419 }
 420
 421 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 422     struct usb_host_config *config, unsigned char *buffer, int size)
 423 {
 424         struct device *ddev = &dev->dev;
 425         unsigned char *buffer0 = buffer;
 426         int cfgno;
 427         int nintf, nintf_orig;
 428         int i, j, n;
 429         struct usb_interface_cache *intfc;
 430         unsigned char *buffer2;
 431         int size2;
 432         struct usb_descriptor_header *header;
 433         int len, retval;
 434         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 435         unsigned iad_num = 0;
 436
 437         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 438         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 439             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 440             config->desc.bLength > size) {
 441                 dev_err(ddev, "invalid descriptor for config index %d: "
 442                     "type = 0x%X, length = %d\n", cfgidx,
 443                     config->desc.bDescriptorType, config->desc.bLength);
 444                 return -EINVAL;
 445         }
 446         cfgno = config->desc.bConfigurationValue;
 447
 448         buffer += config->desc.bLength;
 449         size -= config->desc.bLength;
 450
 451         nintf = nintf_orig = config->desc.bNumInterfaces;
 452         if (nintf > USB_MAXINTERFACES) {
 453                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 454                     "using maximum allowed: %d\n",
 455                     cfgno, nintf, USB_MAXINTERFACES);
 456                 nintf = USB_MAXINTERFACES;
 457         }
 458
 459         /* Go through the descriptors, checking their length and counting the
 460          * number of altsettings for each interface */
 461         n = 0;
 462         for ((buffer2 = buffer, size2 = size);
 463               size2 > 0;
 464              (buffer2 += header->bLength, size2 -= header->bLength)) {
 465
 466                 if (size2 < sizeof(struct usb_descriptor_header)) {
 467                         dev_warn(ddev, "config %d descriptor has %d excess "
 468                             "byte%s, ignoring\n",
 469                             cfgno, size2, plural(size2));
 470                         break;
 471                 }
 472
 473                 header = (struct usb_descriptor_header *) buffer2;
 474                 if ((header->bLength > size2) || (header->bLength < 2)) {
 475                         dev_warn(ddev, "config %d has an invalid descriptor "
 476                             "of length %d, skipping remainder of the config\n",
 477                             cfgno, header->bLength);
 478                         break;
 479                 }
 480
 481                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 482                         struct usb_interface_descriptor *d;
 483                         int inum;
 484
 485                         d = (struct usb_interface_descriptor *) header;
 486                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 487                                 dev_warn(ddev, "config %d has an invalid "
 488                                     "interface descriptor of length %d, "
 489                                     "skipping\n", cfgno, d->bLength);
 490                                 continue;
 491                         }
 492
 493                         inum = d->bInterfaceNumber;
 494
 495                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 496                             n >= nintf_orig) {
 497                                 dev_warn(ddev, "config %d has more interface "
 498                                     "descriptors, than it declares in "
 499                                     "bNumInterfaces, ignoring interface "
 500                                     "number: %d\n", cfgno, inum);
 501                                 continue;
 502                         }
 503
 504                         if (inum >= nintf_orig)
 505                                 dev_warn(ddev, "config %d has an invalid "
 506                                     "interface number: %d but max is %d\n",
 507                                     cfgno, inum, nintf_orig - 1);
 508
 509                         /* Have we already encountered this interface?
 510                          * Count its altsettings */
 511                         for (i = 0; i < n; ++i) {
 512                                 if (inums[i] == inum)
 513                                         break;
 514                         }
 515                         if (i < n) {
 516                                 if (nalts[i] < 255)
 517                                         ++nalts[i];
 518                         } else if (n < USB_MAXINTERFACES) {
 519                                 inums[n] = inum;
 520                                 nalts[n] = 1;
 521                                 ++n;
 522                         }
 523
 524                 } else if (header->bDescriptorType ==
 525                                 USB_DT_INTERFACE_ASSOCIATION) {
 526                         if (iad_num == USB_MAXIADS) {
 527                                 dev_warn(ddev, "found more Interface "
 528                                                "Association Descriptors "
 529                                                "than allocated for in "
 530                                                "configuration %d\n", cfgno);
 531                         } else {
 532                                 config->intf_assoc[iad_num] =
 533                                         (struct usb_interface_assoc_descriptor
 534                                         *)header;
 535                                 iad_num++;
 536                         }
 537
 538                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 539                             header->bDescriptorType == USB_DT_CONFIG)
 540                         dev_warn(ddev, "config %d contains an unexpected "
 541                             "descriptor of type 0x%X, skipping\n",
 542                             cfgno, header->bDescriptorType);
 543
 544         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 545         size = buffer2 - buffer;
 546         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 547
 548         if (n != nintf)
 549                 dev_warn(ddev, "config %d has %d interface%s, different from "
 550                     "the descriptor's value: %d\n",
 551                     cfgno, n, plural(n), nintf_orig);
 552         else if (n == 0)
 553                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 554         config->desc.bNumInterfaces = nintf = n;
 555
 556         /* Check for missing interface numbers */
 557         for (i = 0; i < nintf; ++i) {
 558                 for (j = 0; j < nintf; ++j) {
 559                         if (inums[j] == i)
 560                                 break;
 561                 }
 562                 if (j >= nintf)
 563                         dev_warn(ddev, "config %d has no interface number "
 564                             "%d\n", cfgno, i);
 565         }
 566
 567         /* Allocate the usb_interface_caches and altsetting arrays */
 568         for (i = 0; i < nintf; ++i) {
 569                 j = nalts[i];
 570                 if (j > USB_MAXALTSETTING) {
 571                         dev_warn(ddev, "too many alternate settings for "
 572                             "config %d interface %d: %d, "
 573                             "using maximum allowed: %d\n",
 574                             cfgno, inums[i], j, USB_MAXALTSETTING);
 575                         nalts[i] = j = USB_MAXALTSETTING;
 576                 }
 577
 578                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 579                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 580                 if (!intfc)
 581                         return -ENOMEM;
 582                 kref_init(&intfc->ref);
 583         }
 584
 585         /* FIXME: parse the BOS descriptor */
 586
 587         /* Skip over any Class Specific or Vendor Specific descriptors;
 588          * find the first interface descriptor */
 589         config->extra = buffer;
 590         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 591             USB_DT_INTERFACE, &n);
 592         config->extralen = i;
 593         if (n > 0)
 594                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 595                     n, plural(n), "configuration");
 596         buffer += i;
 597         size -= i;
 598
 599         /* Parse all the interface/altsetting descriptors */
 600         while (size > 0) {
 601                 retval = usb_parse_interface(ddev, cfgno, config,
 602                     buffer, size, inums, nalts);
 603                 if (retval < 0)
 604                         return retval;
 605
 606                 buffer += retval;
 607                 size -= retval;
 608         }
 609
 610         /* Check for missing altsettings */
 611         for (i = 0; i < nintf; ++i) {
 612                 intfc = config->intf_cache[i];
 613                 for (j = 0; j < intfc->num_altsetting; ++j) {
 614                         for (n = 0; n < intfc->num_altsetting; ++n) {
 615                                 if (intfc->altsetting[n].desc.
 616                                     bAlternateSetting == j)
 617                                         break;
 618                         }
 619                         if (n >= intfc->num_altsetting)
 620                                 dev_warn(ddev, "config %d interface %d has no "
 621                                     "altsetting %d\n", cfgno, inums[i], j);
 622                 }
 623         }
 624
 625         return 0;
 626 }
 627
 628 /* hub-only!! ... and only exported for reset/reinit path.
 629  * otherwise used internally on disconnect/destroy path
 630  */
 631 void usb_destroy_configuration(struct usb_device *dev)
 632 {
 633         int c, i;
 634
 635         if (!dev->config)
 636                 return;
 637
 638         if (dev->rawdescriptors) {
 639                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 640                         kfree(dev->rawdescriptors[i]);
 641
 642                 kfree(dev->rawdescriptors);
 643                 dev->rawdescriptors = NULL;
 644         }
 645
 646         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 647                 struct usb_host_config *cf = &dev->config[c];
 648
 649                 kfree(cf->string);
 650                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 651                         if (cf->intf_cache[i])
 652                                 kref_put(&cf->intf_cache[i]->ref,
 653                                           usb_release_interface_cache);
 654                 }
 655         }
 656         kfree(dev->config);
 657         dev->config = NULL;
 658 }
 659
 660
 661 /*
 662  * Get the USB config descriptors, cache and parse'em
 663  *
 664  * hub-only!! ... and only in reset path, or usb_new_device()
 665  * (used by real hubs and virtual root hubs)
 666  */
 667 int usb_get_configuration(struct usb_device *dev)
 668 {
 669         struct device *ddev = &dev->dev;
 670         int ncfg = dev->descriptor.bNumConfigurations;
 671         int result = 0;
 672         unsigned int cfgno, length;
 673         unsigned char *bigbuffer;
 674         struct usb_config_descriptor *desc;
 675
 676         cfgno = 0;
 677         result = -ENOMEM;
 678         if (ncfg > USB_MAXCONFIG) {
 679                 dev_warn(ddev, "too many configurations: %d, "
 680                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 681                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 682         }
 683
 684         if (ncfg < 1) {
 685                 dev_err(ddev, "no configurations\n");
 686                 return -EINVAL;
 687         }
 688
 689         length = ncfg * sizeof(struct usb_host_config);
 690         dev->config = kzalloc(length, GFP_KERNEL);
 691         if (!dev->config)
 692                 goto err2;
 693
 694         length = ncfg * sizeof(char *);
 695         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 696         if (!dev->rawdescriptors)
 697                 goto err2;
 698
 699         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 700         if (!desc)
 701                 goto err2;
 702
 703         result = 0;
 704         for (; cfgno < ncfg; cfgno++) {
 705                 /* We grab just the first descriptor so we know how long
 706                  * the whole configuration is */
 707                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 708                     desc, USB_DT_CONFIG_SIZE);
 709                 if (result < 0) {
 710                         dev_err(ddev, "unable to read config index %d "
 711                             "descriptor/%s: %d\n", cfgno, "start", result);
 712                         if (result != -EPIPE)
 713                                 goto err;
 714                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 715                         dev->descriptor.bNumConfigurations = cfgno;
 716                         break;
 717                 } else if (result < 4) {
 718                         dev_err(ddev, "config index %d descriptor too short "
 719                             "(expected %i, got %i)\n", cfgno,
 720                             USB_DT_CONFIG_SIZE, result);
 721                         result = -EINVAL;
 722                         goto err;
 723                 }
 724                 length = max((int) le16_to_cpu(desc->wTotalLength),
 725                     USB_DT_CONFIG_SIZE);
 726
 727                 /* Now that we know the length, get the whole thing */
 728                 bigbuffer = kmalloc(length, GFP_KERNEL);
 729                 if (!bigbuffer) {
 730                         result = -ENOMEM;
 731                         goto err;
 732                 }
 733
 734                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 735                         msleep(100);
 736
 737                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 738                     bigbuffer, length);
 739                 if (result < 0) {
 740                         dev_err(ddev, "unable to read config index %d "
 741                             "descriptor/%s\n", cfgno, "all");
 742                         kfree(bigbuffer);
 743                         goto err;
 744                 }
 745                 if (result < length) {
 746                         dev_warn(ddev, "config index %d descriptor too short "
 747                             "(expected %i, got %i)\n", cfgno, length, result);
 748                         length = result;
 749                 }
 750
 751                 dev->rawdescriptors[cfgno] = bigbuffer;
 752
 753                 result = usb_parse_configuration(dev, cfgno,
 754                     &dev->config[cfgno], bigbuffer, length);
 755                 if (result < 0) {
 756                         ++cfgno;
 757                         goto err;
 758                 }
 759         }
 760         result = 0;
 761
 762 err:
 763         kfree(desc);
 764         dev->descriptor.bNumConfigurations = cfgno;
 765 err2:
 766         if (result == -ENOMEM)
 767                 dev_err(ddev, "out of memory\n");
 768         return result;
 769 }
 770
 771 void usb_release_bos_descriptor(struct usb_device *dev)
 772 {
 773         if (dev->bos) {
 774                 kfree(dev->bos->desc);
 775                 kfree(dev->bos);
 776                 dev->bos = NULL;
 777         }
 778 }
 779
 780 /* Get BOS descriptor set */
 781 int usb_get_bos_descriptor(struct usb_device *dev)
 782 {
 783         struct device *ddev = &dev->dev;
 784         struct usb_bos_descriptor *bos;
 785         struct usb_dev_cap_header *cap;
 786         unsigned char *buffer;
 787         int length, total_len, num, i;
 788         int ret;
 789
 790         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 791         if (!bos)
 792                 return -ENOMEM;
 793
 794         /* Get BOS descriptor */
 795         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 796         if (ret < USB_DT_BOS_SIZE) {
 797                 dev_err(ddev, "unable to get BOS descriptor\n");
 798                 if (ret >= 0)
 799                         ret = -ENOMSG;
 800                 kfree(bos);
 801                 return ret;
 802         }
 803
 804         length = bos->bLength;
 805         total_len = le16_to_cpu(bos->wTotalLength);
 806         num = bos->bNumDeviceCaps;
 807         kfree(bos);
 808         if (total_len < length)
 809                 return -EINVAL;
 810
 811         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 812         if (!dev->bos)
 813                 return -ENOMEM;
 814
 815         /* Now let's get the whole BOS descriptor set */
 816         buffer = kzalloc(total_len, GFP_KERNEL);
 817         if (!buffer) {
 818                 ret = -ENOMEM;
 819                 goto err;
 820         }
 821         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 822
 823         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 824         if (ret < total_len) {
 825                 dev_err(ddev, "unable to get BOS descriptor set\n");
 826                 if (ret >= 0)
 827                         ret = -ENOMSG;
 828                 goto err;
 829         }
 830         total_len -= length;
 831
 832         for (i = 0; i < num; i++) {
 833                 buffer += length;
 834                 cap = (struct usb_dev_cap_header *)buffer;
 835                 length = cap->bLength;
 836
 837                 if (total_len < length)
 838                         break;
 839                 total_len -= length;
 840
 841                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 842                         dev_warn(ddev, "descriptor type invalid, skip\n");
 843                         continue;
 844                 }
 845
 846                 switch (cap->bDevCapabilityType) {
 847                 case USB_CAP_TYPE_WIRELESS_USB:
 848                         /* Wireless USB cap descriptor is handled by wusb */
 849                         break;
 850                 case USB_CAP_TYPE_EXT:
 851                         dev->bos->ext_cap =
 852                                 (struct usb_ext_cap_descriptor *)buffer;
 853                         break;
 854                 case USB_SS_CAP_TYPE:
 855                         dev->bos->ss_cap =
 856                                 (struct usb_ss_cap_descriptor *)buffer;
 857                         break;
 858                 case USB_SSP_CAP_TYPE:
 859                         dev->bos->ssp_cap =
 860                                 (struct usb_ssp_cap_descriptor *)buffer;
 861                         break;
 862                 case CONTAINER_ID_TYPE:
 863                         dev->bos->ss_id =
 864                                 (struct usb_ss_container_id_descriptor *)buffer;
 865                         break;
 866                 default:
 867                         break;
 868                 }
 869         }
 870
 871         return 0;
 872
 873 err:
 874         usb_release_bos_descriptor(dev);
 875         return ret;
 876 }