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