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_ssp_isoc_endpoint_companion(struct device *ddev,
  47                 int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
  48                 unsigned char *buffer, int size)
  49 {
  50         struct usb_ssp_isoc_ep_comp_descriptor *desc;
  51
  52         /*
  53          * The SuperSpeedPlus Isoc endpoint companion descriptor immediately
  54          * follows the SuperSpeed Endpoint Companion descriptor
  55          */
  56         desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;
  57         if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||
  58             size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {
  59                 dev_warn(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"
  60                          "for config %d interface %d altsetting %d ep %d.\n",
  61                          cfgno, inum, asnum, ep->desc.bEndpointAddress);
  62                 return;
  63         }
  64         memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);
  65 }
  66
  67 static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
  68                 int inum, int asnum, struct usb_host_endpoint *ep,
  69                 unsigned char *buffer, int size)
  70 {
  71         struct usb_ss_ep_comp_descriptor *desc;
  72         int max_tx;
  73
  74         /* The SuperSpeed endpoint companion descriptor is supposed to
  75          * be the first thing immediately following the endpoint descriptor.
  76          */
  77         desc = (struct usb_ss_ep_comp_descriptor *) buffer;
  78
  79         if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
  80                         size < USB_DT_SS_EP_COMP_SIZE) {
  81                 dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
  82                                 " interface %d altsetting %d ep %d: "
  83                                 "using minimum values\n",
  84                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  85
  86                 /* Fill in some default values.
  87                  * Leave bmAttributes as zero, which will mean no streams for
  88                  * bulk, and isoc won't support multiple bursts of packets.
  89                  * With bursts of only one packet, and a Mult of 1, the max
  90                  * amount of data moved per endpoint service interval is one
  91                  * packet.
  92                  */
  93                 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
  94                 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
  95                 if (usb_endpoint_xfer_isoc(&ep->desc) ||
  96                                 usb_endpoint_xfer_int(&ep->desc))
  97                         ep->ss_ep_comp.wBytesPerInterval =
  98                                         ep->desc.wMaxPacketSize;
  99                 return;
 100         }
 101         buffer += desc->bLength;
 102         size -= desc->bLength;
 103         memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 104
 105         /* Check the various values */
 106         if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 107                 dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
 108                                 "config %d interface %d altsetting %d ep %d: "
 109                                 "setting to zero\n", desc->bMaxBurst,
 110                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 111                 ep->ss_ep_comp.bMaxBurst = 0;
 112         } else if (desc->bMaxBurst > 15) {
 113                 dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
 114                                 "config %d interface %d altsetting %d ep %d: "
 115                                 "setting to 15\n", desc->bMaxBurst,
 116                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 117                 ep->ss_ep_comp.bMaxBurst = 15;
 118         }
 119
 120         if ((usb_endpoint_xfer_control(&ep->desc) ||
 121                         usb_endpoint_xfer_int(&ep->desc)) &&
 122                                 desc->bmAttributes != 0) {
 123                 dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
 124                                 "config %d interface %d altsetting %d ep %d: "
 125                                 "setting to zero\n",
 126                                 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 127                                 desc->bmAttributes,
 128                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 129                 ep->ss_ep_comp.bmAttributes = 0;
 130         } else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 131                         desc->bmAttributes > 16) {
 132                 dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
 133                                 "config %d interface %d altsetting %d ep %d: "
 134                                 "setting to max\n",
 135                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 136                 ep->ss_ep_comp.bmAttributes = 16;
 137         } else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 138                    !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
 139                    USB_SS_MULT(desc->bmAttributes) > 3) {
 140                 dev_warn(ddev, "Isoc endpoint has Mult of %d in "
 141                                 "config %d interface %d altsetting %d ep %d: "
 142                                 "setting to 3\n",
 143                                 USB_SS_MULT(desc->bmAttributes),
 144                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 145                 ep->ss_ep_comp.bmAttributes = 2;
 146         }
 147
 148         if (usb_endpoint_xfer_isoc(&ep->desc))
 149                 max_tx = (desc->bMaxBurst + 1) *
 150                         (USB_SS_MULT(desc->bmAttributes)) *
 151                         usb_endpoint_maxp(&ep->desc);
 152         else if (usb_endpoint_xfer_int(&ep->desc))
 153                 max_tx = usb_endpoint_maxp(&ep->desc) *
 154                         (desc->bMaxBurst + 1);
 155         else
 156                 max_tx = 999999;
 157         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 158                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 159                                 "config %d interface %d altsetting %d ep %d: "
 160                                 "setting to %d\n",
 161                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 162                                 le16_to_cpu(desc->wBytesPerInterval),
 163                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 164                                 max_tx);
 165                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 166         }
 167         /* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
 168         if (usb_endpoint_xfer_isoc(&ep->desc) &&
 169             USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
 170                 usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 171                                                         ep, buffer, size);
 172 }
 173
 174 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 175     int asnum, struct usb_host_interface *ifp, int num_ep,
 176     unsigned char *buffer, int size)
 177 {
 178         unsigned char *buffer0 = buffer;
 179         struct usb_endpoint_descriptor *d;
 180         struct usb_host_endpoint *endpoint;
 181         int n, i, j, retval;
 182
 183         d = (struct usb_endpoint_descriptor *) buffer;
 184         buffer += d->bLength;
 185         size -= d->bLength;
 186
 187         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 188                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 189         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 190                 n = USB_DT_ENDPOINT_SIZE;
 191         else {
 192                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 193                     "invalid endpoint descriptor of length %d, skipping\n",
 194                     cfgno, inum, asnum, d->bLength);
 195                 goto skip_to_next_endpoint_or_interface_descriptor;
 196         }
 197
 198         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 199         if (i >= 16 || i == 0) {
 200                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 201                     "invalid endpoint with address 0x%X, skipping\n",
 202                     cfgno, inum, asnum, d->bEndpointAddress);
 203                 goto skip_to_next_endpoint_or_interface_descriptor;
 204         }
 205
 206         /* Only store as many endpoints as we have room for */
 207         if (ifp->desc.bNumEndpoints >= num_ep)
 208                 goto skip_to_next_endpoint_or_interface_descriptor;
 209
 210         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 211         ++ifp->desc.bNumEndpoints;
 212
 213         memcpy(&endpoint->desc, d, n);
 214         INIT_LIST_HEAD(&endpoint->urb_list);
 215
 216         /* Fix up bInterval values outside the legal range. Use 32 ms if no
 217          * proper value can be guessed. */
 218         i = 0;          /* i = min, j = max, n = default */
 219         j = 255;
 220         if (usb_endpoint_xfer_int(d)) {
 221                 i = 1;
 222                 switch (to_usb_device(ddev)->speed) {
 223                 case USB_SPEED_SUPER_PLUS:
 224                 case USB_SPEED_SUPER:
 225                 case USB_SPEED_HIGH:
 226                         /* Many device manufacturers are using full-speed
 227                          * bInterval values in high-speed interrupt endpoint
 228                          * descriptors. Try to fix those and fall back to a
 229                          * 32 ms default value otherwise. */
 230                         n = fls(d->bInterval*8);
 231                         if (n == 0)
 232                                 n = 9;  /* 32 ms = 2^(9-1) uframes */
 233                         j = 16;
 234
 235                         /*
 236                          * Adjust bInterval for quirked devices.
 237                          * This quirk fixes bIntervals reported in
 238                          * linear microframes.
 239                          */
 240                         if (to_usb_device(ddev)->quirks &
 241                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 242                                 n = clamp(fls(d->bInterval), i, j);
 243                                 i = j = n;
 244                         }
 245                         break;
 246                 default:                /* USB_SPEED_FULL or _LOW */
 247                         /* For low-speed, 10 ms is the official minimum.
 248                          * But some "overclocked" devices might want faster
 249                          * polling so we'll allow it. */
 250                         n = 32;
 251                         break;
 252                 }
 253         } else if (usb_endpoint_xfer_isoc(d)) {
 254                 i = 1;
 255                 j = 16;
 256                 switch (to_usb_device(ddev)->speed) {
 257                 case USB_SPEED_HIGH:
 258                         n = 9;          /* 32 ms = 2^(9-1) uframes */
 259                         break;
 260                 default:                /* USB_SPEED_FULL */
 261                         n = 6;          /* 32 ms = 2^(6-1) frames */
 262                         break;
 263                 }
 264         }
 265         if (d->bInterval < i || d->bInterval > j) {
 266                 dev_warn(ddev, "config %d interface %d altsetting %d "
 267                     "endpoint 0x%X has an invalid bInterval %d, "
 268                     "changing to %d\n",
 269                     cfgno, inum, asnum,
 270                     d->bEndpointAddress, d->bInterval, n);
 271                 endpoint->desc.bInterval = n;
 272         }
 273
 274         /* Some buggy low-speed devices have Bulk endpoints, which is
 275          * explicitly forbidden by the USB spec.  In an attempt to make
 276          * them usable, we will try treating them as Interrupt endpoints.
 277          */
 278         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 279                         usb_endpoint_xfer_bulk(d)) {
 280                 dev_warn(ddev, "config %d interface %d altsetting %d "
 281                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 282                     cfgno, inum, asnum, d->bEndpointAddress);
 283                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 284                 endpoint->desc.bInterval = 1;
 285                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 286                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 287         }
 288
 289         /*
 290          * Some buggy high speed devices have bulk endpoints using
 291          * maxpacket sizes other than 512.  High speed HCDs may not
 292          * be able to handle that particular bug, so let's warn...
 293          */
 294         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 295                         && usb_endpoint_xfer_bulk(d)) {
 296                 unsigned maxp;
 297
 298                 maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
 299                 if (maxp != 512)
 300                         dev_warn(ddev, "config %d interface %d altsetting %d "
 301                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 302                                 cfgno, inum, asnum, d->bEndpointAddress,
 303                                 maxp);
 304         }
 305
 306         /* Parse a possible SuperSpeed endpoint companion descriptor */
 307         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 308                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 309                                 inum, asnum, endpoint, buffer, size);
 310
 311         /* Skip over any Class Specific or Vendor Specific descriptors;
 312          * find the next endpoint or interface descriptor */
 313         endpoint->extra = buffer;
 314         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 315                         USB_DT_INTERFACE, &n);
 316         endpoint->extralen = i;
 317         retval = buffer - buffer0 + i;
 318         if (n > 0)
 319                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 320                     n, plural(n), "endpoint");
 321         return retval;
 322
 323 skip_to_next_endpoint_or_interface_descriptor:
 324         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 325             USB_DT_INTERFACE, NULL);
 326         return buffer - buffer0 + i;
 327 }
 328
 329 void usb_release_interface_cache(struct kref *ref)
 330 {
 331         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 332         int j;
 333
 334         for (j = 0; j < intfc->num_altsetting; j++) {
 335                 struct usb_host_interface *alt = &intfc->altsetting[j];
 336
 337                 kfree(alt->endpoint);
 338                 kfree(alt->string);
 339         }
 340         kfree(intfc);
 341 }
 342
 343 static int usb_parse_interface(struct device *ddev, int cfgno,
 344     struct usb_host_config *config, unsigned char *buffer, int size,
 345     u8 inums[], u8 nalts[])
 346 {
 347         unsigned char *buffer0 = buffer;
 348         struct usb_interface_descriptor *d;
 349         int inum, asnum;
 350         struct usb_interface_cache *intfc;
 351         struct usb_host_interface *alt;
 352         int i, n;
 353         int len, retval;
 354         int num_ep, num_ep_orig;
 355
 356         d = (struct usb_interface_descriptor *) buffer;
 357         buffer += d->bLength;
 358         size -= d->bLength;
 359
 360         if (d->bLength < USB_DT_INTERFACE_SIZE)
 361                 goto skip_to_next_interface_descriptor;
 362
 363         /* Which interface entry is this? */
 364         intfc = NULL;
 365         inum = d->bInterfaceNumber;
 366         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 367                 if (inums[i] == inum) {
 368                         intfc = config->intf_cache[i];
 369                         break;
 370                 }
 371         }
 372         if (!intfc || intfc->num_altsetting >= nalts[i])
 373                 goto skip_to_next_interface_descriptor;
 374
 375         /* Check for duplicate altsetting entries */
 376         asnum = d->bAlternateSetting;
 377         for ((i = 0, alt = &intfc->altsetting[0]);
 378               i < intfc->num_altsetting;
 379              (++i, ++alt)) {
 380                 if (alt->desc.bAlternateSetting == asnum) {
 381                         dev_warn(ddev, "Duplicate descriptor for config %d "
 382                             "interface %d altsetting %d, skipping\n",
 383                             cfgno, inum, asnum);
 384                         goto skip_to_next_interface_descriptor;
 385                 }
 386         }
 387
 388         ++intfc->num_altsetting;
 389         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 390
 391         /* Skip over any Class Specific or Vendor Specific descriptors;
 392          * find the first endpoint or interface descriptor */
 393         alt->extra = buffer;
 394         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 395             USB_DT_INTERFACE, &n);
 396         alt->extralen = i;
 397         if (n > 0)
 398                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 399                     n, plural(n), "interface");
 400         buffer += i;
 401         size -= i;
 402
 403         /* Allocate space for the right(?) number of endpoints */
 404         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 405         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 406         if (num_ep > USB_MAXENDPOINTS) {
 407                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 408                     "altsetting %d: %d, using maximum allowed: %d\n",
 409                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 410                 num_ep = USB_MAXENDPOINTS;
 411         }
 412
 413         if (num_ep > 0) {
 414                 /* Can't allocate 0 bytes */
 415                 len = sizeof(struct usb_host_endpoint) * num_ep;
 416                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 417                 if (!alt->endpoint)
 418                         return -ENOMEM;
 419         }
 420
 421         /* Parse all the endpoint descriptors */
 422         n = 0;
 423         while (size > 0) {
 424                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 425                      == USB_DT_INTERFACE)
 426                         break;
 427                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 428                     num_ep, buffer, size);
 429                 if (retval < 0)
 430                         return retval;
 431                 ++n;
 432
 433                 buffer += retval;
 434                 size -= retval;
 435         }
 436
 437         if (n != num_ep_orig)
 438                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 439                     "endpoint descriptor%s, different from the interface "
 440                     "descriptor's value: %d\n",
 441                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 442         return buffer - buffer0;
 443
 444 skip_to_next_interface_descriptor:
 445         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 446             USB_DT_INTERFACE, NULL);
 447         return buffer - buffer0 + i;
 448 }
 449
 450 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 451     struct usb_host_config *config, unsigned char *buffer, int size)
 452 {
 453         struct device *ddev = &dev->dev;
 454         unsigned char *buffer0 = buffer;
 455         int cfgno;
 456         int nintf, nintf_orig;
 457         int i, j, n;
 458         struct usb_interface_cache *intfc;
 459         unsigned char *buffer2;
 460         int size2;
 461         struct usb_descriptor_header *header;
 462         int len, retval;
 463         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 464         unsigned iad_num = 0;
 465
 466         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 467         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 468             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 469             config->desc.bLength > size) {
 470                 dev_err(ddev, "invalid descriptor for config index %d: "
 471                     "type = 0x%X, length = %d\n", cfgidx,
 472                     config->desc.bDescriptorType, config->desc.bLength);
 473                 return -EINVAL;
 474         }
 475         cfgno = config->desc.bConfigurationValue;
 476
 477         buffer += config->desc.bLength;
 478         size -= config->desc.bLength;
 479
 480         nintf = nintf_orig = config->desc.bNumInterfaces;
 481         if (nintf > USB_MAXINTERFACES) {
 482                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 483                     "using maximum allowed: %d\n",
 484                     cfgno, nintf, USB_MAXINTERFACES);
 485                 nintf = USB_MAXINTERFACES;
 486         }
 487
 488         /* Go through the descriptors, checking their length and counting the
 489          * number of altsettings for each interface */
 490         n = 0;
 491         for ((buffer2 = buffer, size2 = size);
 492               size2 > 0;
 493              (buffer2 += header->bLength, size2 -= header->bLength)) {
 494
 495                 if (size2 < sizeof(struct usb_descriptor_header)) {
 496                         dev_warn(ddev, "config %d descriptor has %d excess "
 497                             "byte%s, ignoring\n",
 498                             cfgno, size2, plural(size2));
 499                         break;
 500                 }
 501
 502                 header = (struct usb_descriptor_header *) buffer2;
 503                 if ((header->bLength > size2) || (header->bLength < 2)) {
 504                         dev_warn(ddev, "config %d has an invalid descriptor "
 505                             "of length %d, skipping remainder of the config\n",
 506                             cfgno, header->bLength);
 507                         break;
 508                 }
 509
 510                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 511                         struct usb_interface_descriptor *d;
 512                         int inum;
 513
 514                         d = (struct usb_interface_descriptor *) header;
 515                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 516                                 dev_warn(ddev, "config %d has an invalid "
 517                                     "interface descriptor of length %d, "
 518                                     "skipping\n", cfgno, d->bLength);
 519                                 continue;
 520                         }
 521
 522                         inum = d->bInterfaceNumber;
 523
 524                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 525                             n >= nintf_orig) {
 526                                 dev_warn(ddev, "config %d has more interface "
 527                                     "descriptors, than it declares in "
 528                                     "bNumInterfaces, ignoring interface "
 529                                     "number: %d\n", cfgno, inum);
 530                                 continue;
 531                         }
 532
 533                         if (inum >= nintf_orig)
 534                                 dev_warn(ddev, "config %d has an invalid "
 535                                     "interface number: %d but max is %d\n",
 536                                     cfgno, inum, nintf_orig - 1);
 537
 538                         /* Have we already encountered this interface?
 539                          * Count its altsettings */
 540                         for (i = 0; i < n; ++i) {
 541                                 if (inums[i] == inum)
 542                                         break;
 543                         }
 544                         if (i < n) {
 545                                 if (nalts[i] < 255)
 546                                         ++nalts[i];
 547                         } else if (n < USB_MAXINTERFACES) {
 548                                 inums[n] = inum;
 549                                 nalts[n] = 1;
 550                                 ++n;
 551                         }
 552
 553                 } else if (header->bDescriptorType ==
 554                                 USB_DT_INTERFACE_ASSOCIATION) {
 555                         if (iad_num == USB_MAXIADS) {
 556                                 dev_warn(ddev, "found more Interface "
 557                                                "Association Descriptors "
 558                                                "than allocated for in "
 559                                                "configuration %d\n", cfgno);
 560                         } else {
 561                                 config->intf_assoc[iad_num] =
 562                                         (struct usb_interface_assoc_descriptor
 563                                         *)header;
 564                                 iad_num++;
 565                         }
 566
 567                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 568                             header->bDescriptorType == USB_DT_CONFIG)
 569                         dev_warn(ddev, "config %d contains an unexpected "
 570                             "descriptor of type 0x%X, skipping\n",
 571                             cfgno, header->bDescriptorType);
 572
 573         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 574         size = buffer2 - buffer;
 575         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 576
 577         if (n != nintf)
 578                 dev_warn(ddev, "config %d has %d interface%s, different from "
 579                     "the descriptor's value: %d\n",
 580                     cfgno, n, plural(n), nintf_orig);
 581         else if (n == 0)
 582                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 583         config->desc.bNumInterfaces = nintf = n;
 584
 585         /* Check for missing interface numbers */
 586         for (i = 0; i < nintf; ++i) {
 587                 for (j = 0; j < nintf; ++j) {
 588                         if (inums[j] == i)
 589                                 break;
 590                 }
 591                 if (j >= nintf)
 592                         dev_warn(ddev, "config %d has no interface number "
 593                             "%d\n", cfgno, i);
 594         }
 595
 596         /* Allocate the usb_interface_caches and altsetting arrays */
 597         for (i = 0; i < nintf; ++i) {
 598                 j = nalts[i];
 599                 if (j > USB_MAXALTSETTING) {
 600                         dev_warn(ddev, "too many alternate settings for "
 601                             "config %d interface %d: %d, "
 602                             "using maximum allowed: %d\n",
 603                             cfgno, inums[i], j, USB_MAXALTSETTING);
 604                         nalts[i] = j = USB_MAXALTSETTING;
 605                 }
 606
 607                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 608                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 609                 if (!intfc)
 610                         return -ENOMEM;
 611                 kref_init(&intfc->ref);
 612         }
 613
 614         /* FIXME: parse the BOS descriptor */
 615
 616         /* Skip over any Class Specific or Vendor Specific descriptors;
 617          * find the first interface descriptor */
 618         config->extra = buffer;
 619         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 620             USB_DT_INTERFACE, &n);
 621         config->extralen = i;
 622         if (n > 0)
 623                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 624                     n, plural(n), "configuration");
 625         buffer += i;
 626         size -= i;
 627
 628         /* Parse all the interface/altsetting descriptors */
 629         while (size > 0) {
 630                 retval = usb_parse_interface(ddev, cfgno, config,
 631                     buffer, size, inums, nalts);
 632                 if (retval < 0)
 633                         return retval;
 634
 635                 buffer += retval;
 636                 size -= retval;
 637         }
 638
 639         /* Check for missing altsettings */
 640         for (i = 0; i < nintf; ++i) {
 641                 intfc = config->intf_cache[i];
 642                 for (j = 0; j < intfc->num_altsetting; ++j) {
 643                         for (n = 0; n < intfc->num_altsetting; ++n) {
 644                                 if (intfc->altsetting[n].desc.
 645                                     bAlternateSetting == j)
 646                                         break;
 647                         }
 648                         if (n >= intfc->num_altsetting)
 649                                 dev_warn(ddev, "config %d interface %d has no "
 650                                     "altsetting %d\n", cfgno, inums[i], j);
 651                 }
 652         }
 653
 654         return 0;
 655 }
 656
 657 /* hub-only!! ... and only exported for reset/reinit path.
 658  * otherwise used internally on disconnect/destroy path
 659  */
 660 void usb_destroy_configuration(struct usb_device *dev)
 661 {
 662         int c, i;
 663
 664         if (!dev->config)
 665                 return;
 666
 667         if (dev->rawdescriptors) {
 668                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 669                         kfree(dev->rawdescriptors[i]);
 670
 671                 kfree(dev->rawdescriptors);
 672                 dev->rawdescriptors = NULL;
 673         }
 674
 675         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 676                 struct usb_host_config *cf = &dev->config[c];
 677
 678                 kfree(cf->string);
 679                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 680                         if (cf->intf_cache[i])
 681                                 kref_put(&cf->intf_cache[i]->ref,
 682                                           usb_release_interface_cache);
 683                 }
 684         }
 685         kfree(dev->config);
 686         dev->config = NULL;
 687 }
 688
 689
 690 /*
 691  * Get the USB config descriptors, cache and parse'em
 692  *
 693  * hub-only!! ... and only in reset path, or usb_new_device()
 694  * (used by real hubs and virtual root hubs)
 695  */
 696 int usb_get_configuration(struct usb_device *dev)
 697 {
 698         struct device *ddev = &dev->dev;
 699         int ncfg = dev->descriptor.bNumConfigurations;
 700         int result = 0;
 701         unsigned int cfgno, length;
 702         unsigned char *bigbuffer;
 703         struct usb_config_descriptor *desc;
 704
 705         cfgno = 0;
 706         result = -ENOMEM;
 707         if (ncfg > USB_MAXCONFIG) {
 708                 dev_warn(ddev, "too many configurations: %d, "
 709                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 710                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 711         }
 712
 713         if (ncfg < 1) {
 714                 dev_err(ddev, "no configurations\n");
 715                 return -EINVAL;
 716         }
 717
 718         length = ncfg * sizeof(struct usb_host_config);
 719         dev->config = kzalloc(length, GFP_KERNEL);
 720         if (!dev->config)
 721                 goto err2;
 722
 723         length = ncfg * sizeof(char *);
 724         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 725         if (!dev->rawdescriptors)
 726                 goto err2;
 727
 728         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 729         if (!desc)
 730                 goto err2;
 731
 732         result = 0;
 733         for (; cfgno < ncfg; cfgno++) {
 734                 /* We grab just the first descriptor so we know how long
 735                  * the whole configuration is */
 736                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 737                     desc, USB_DT_CONFIG_SIZE);
 738                 if (result < 0) {
 739                         dev_err(ddev, "unable to read config index %d "
 740                             "descriptor/%s: %d\n", cfgno, "start", result);
 741                         if (result != -EPIPE)
 742                                 goto err;
 743                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 744                         dev->descriptor.bNumConfigurations = cfgno;
 745                         break;
 746                 } else if (result < 4) {
 747                         dev_err(ddev, "config index %d descriptor too short "
 748                             "(expected %i, got %i)\n", cfgno,
 749                             USB_DT_CONFIG_SIZE, result);
 750                         result = -EINVAL;
 751                         goto err;
 752                 }
 753                 length = max((int) le16_to_cpu(desc->wTotalLength),
 754                     USB_DT_CONFIG_SIZE);
 755
 756                 /* Now that we know the length, get the whole thing */
 757                 bigbuffer = kmalloc(length, GFP_KERNEL);
 758                 if (!bigbuffer) {
 759                         result = -ENOMEM;
 760                         goto err;
 761                 }
 762
 763                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 764                         msleep(100);
 765
 766                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 767                     bigbuffer, length);
 768                 if (result < 0) {
 769                         dev_err(ddev, "unable to read config index %d "
 770                             "descriptor/%s\n", cfgno, "all");
 771                         kfree(bigbuffer);
 772                         goto err;
 773                 }
 774                 if (result < length) {
 775                         dev_warn(ddev, "config index %d descriptor too short "
 776                             "(expected %i, got %i)\n", cfgno, length, result);
 777                         length = result;
 778                 }
 779
 780                 dev->rawdescriptors[cfgno] = bigbuffer;
 781
 782                 result = usb_parse_configuration(dev, cfgno,
 783                     &dev->config[cfgno], bigbuffer, length);
 784                 if (result < 0) {
 785                         ++cfgno;
 786                         goto err;
 787                 }
 788         }
 789         result = 0;
 790
 791 err:
 792         kfree(desc);
 793         dev->descriptor.bNumConfigurations = cfgno;
 794 err2:
 795         if (result == -ENOMEM)
 796                 dev_err(ddev, "out of memory\n");
 797         return result;
 798 }
 799
 800 void usb_release_bos_descriptor(struct usb_device *dev)
 801 {
 802         if (dev->bos) {
 803                 kfree(dev->bos->desc);
 804                 kfree(dev->bos);
 805                 dev->bos = NULL;
 806         }
 807 }
 808
 809 /* Get BOS descriptor set */
 810 int usb_get_bos_descriptor(struct usb_device *dev)
 811 {
 812         struct device *ddev = &dev->dev;
 813         struct usb_bos_descriptor *bos;
 814         struct usb_dev_cap_header *cap;
 815         unsigned char *buffer;
 816         int length, total_len, num, i;
 817         int ret;
 818
 819         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 820         if (!bos)
 821                 return -ENOMEM;
 822
 823         /* Get BOS descriptor */
 824         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 825         if (ret < USB_DT_BOS_SIZE) {
 826                 dev_err(ddev, "unable to get BOS descriptor\n");
 827                 if (ret >= 0)
 828                         ret = -ENOMSG;
 829                 kfree(bos);
 830                 return ret;
 831         }
 832
 833         length = bos->bLength;
 834         total_len = le16_to_cpu(bos->wTotalLength);
 835         num = bos->bNumDeviceCaps;
 836         kfree(bos);
 837         if (total_len < length)
 838                 return -EINVAL;
 839
 840         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 841         if (!dev->bos)
 842                 return -ENOMEM;
 843
 844         /* Now let's get the whole BOS descriptor set */
 845         buffer = kzalloc(total_len, GFP_KERNEL);
 846         if (!buffer) {
 847                 ret = -ENOMEM;
 848                 goto err;
 849         }
 850         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 851
 852         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 853         if (ret < total_len) {
 854                 dev_err(ddev, "unable to get BOS descriptor set\n");
 855                 if (ret >= 0)
 856                         ret = -ENOMSG;
 857                 goto err;
 858         }
 859         total_len -= length;
 860
 861         for (i = 0; i < num; i++) {
 862                 buffer += length;
 863                 cap = (struct usb_dev_cap_header *)buffer;
 864                 length = cap->bLength;
 865
 866                 if (total_len < length)
 867                         break;
 868                 total_len -= length;
 869
 870                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 871                         dev_warn(ddev, "descriptor type invalid, skip\n");
 872                         continue;
 873                 }
 874
 875                 switch (cap->bDevCapabilityType) {
 876                 case USB_CAP_TYPE_WIRELESS_USB:
 877                         /* Wireless USB cap descriptor is handled by wusb */
 878                         break;
 879                 case USB_CAP_TYPE_EXT:
 880                         dev->bos->ext_cap =
 881                                 (struct usb_ext_cap_descriptor *)buffer;
 882                         break;
 883                 case USB_SS_CAP_TYPE:
 884                         dev->bos->ss_cap =
 885                                 (struct usb_ss_cap_descriptor *)buffer;
 886                         break;
 887                 case USB_SSP_CAP_TYPE:
 888                         dev->bos->ssp_cap =
 889                                 (struct usb_ssp_cap_descriptor *)buffer;
 890                         break;
 891                 case CONTAINER_ID_TYPE:
 892                         dev->bos->ss_id =
 893                                 (struct usb_ss_container_id_descriptor *)buffer;
 894                         break;
 895                 case USB_PTM_CAP_TYPE:
 896                         dev->bos->ptm_cap =
 897                                 (struct usb_ptm_cap_descriptor *)buffer;
 898                 default:
 899                         break;
 900                 }
 901         }
 902
 903         return 0;
 904
 905 err:
 906         usb_release_bos_descriptor(dev);
 907         return ret;
 908 }