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         buffer += desc->bLength;
  79         size -= desc->bLength;
  80
  81         if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
  82                         size < USB_DT_SS_EP_COMP_SIZE) {
  83                 dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
  84                                 " interface %d altsetting %d ep %d: "
  85                                 "using minimum values\n",
  86                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  87
  88                 /* Fill in some default values.
  89                  * Leave bmAttributes as zero, which will mean no streams for
  90                  * bulk, and isoc won't support multiple bursts of packets.
  91                  * With bursts of only one packet, and a Mult of 1, the max
  92                  * amount of data moved per endpoint service interval is one
  93                  * packet.
  94                  */
  95                 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
  96                 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
  97                 if (usb_endpoint_xfer_isoc(&ep->desc) ||
  98                                 usb_endpoint_xfer_int(&ep->desc))
  99                         ep->ss_ep_comp.wBytesPerInterval =
 100                                         ep->desc.wMaxPacketSize;
 101                 return;
 102         }
 103
 104         memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 105
 106         /* Check the various values */
 107         if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 108                 dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
 109                                 "config %d interface %d altsetting %d ep %d: "
 110                                 "setting to zero\n", desc->bMaxBurst,
 111                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 112                 ep->ss_ep_comp.bMaxBurst = 0;
 113         } else if (desc->bMaxBurst > 15) {
 114                 dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
 115                                 "config %d interface %d altsetting %d ep %d: "
 116                                 "setting to 15\n", desc->bMaxBurst,
 117                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 118                 ep->ss_ep_comp.bMaxBurst = 15;
 119         }
 120
 121         if ((usb_endpoint_xfer_control(&ep->desc) ||
 122                         usb_endpoint_xfer_int(&ep->desc)) &&
 123                                 desc->bmAttributes != 0) {
 124                 dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
 125                                 "config %d interface %d altsetting %d ep %d: "
 126                                 "setting to zero\n",
 127                                 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 128                                 desc->bmAttributes,
 129                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 130                 ep->ss_ep_comp.bmAttributes = 0;
 131         } else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 132                         desc->bmAttributes > 16) {
 133                 dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
 134                                 "config %d interface %d altsetting %d ep %d: "
 135                                 "setting to max\n",
 136                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 137                 ep->ss_ep_comp.bmAttributes = 16;
 138         } else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 139                    !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
 140                    USB_SS_MULT(desc->bmAttributes) > 3) {
 141                 dev_warn(ddev, "Isoc endpoint has Mult of %d in "
 142                                 "config %d interface %d altsetting %d ep %d: "
 143                                 "setting to 3\n",
 144                                 USB_SS_MULT(desc->bmAttributes),
 145                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 146                 ep->ss_ep_comp.bmAttributes = 2;
 147         }
 148
 149         /* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
 150         if (usb_endpoint_xfer_isoc(&ep->desc) &&
 151             USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
 152                 usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 153                                                         ep, buffer, size);
 154
 155         if (usb_endpoint_xfer_isoc(&ep->desc))
 156                 max_tx = (desc->bMaxBurst + 1) *
 157                         (USB_SS_MULT(desc->bmAttributes)) *
 158                         usb_endpoint_maxp(&ep->desc);
 159         else if (usb_endpoint_xfer_int(&ep->desc))
 160                 max_tx = usb_endpoint_maxp(&ep->desc) *
 161                         (desc->bMaxBurst + 1);
 162         else
 163                 max_tx = 999999;
 164         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 165                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 166                                 "config %d interface %d altsetting %d ep %d: "
 167                                 "setting to %d\n",
 168                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 169                                 le16_to_cpu(desc->wBytesPerInterval),
 170                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 171                                 max_tx);
 172                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 173         }
 174 }
 175
 176 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 177     int asnum, struct usb_host_interface *ifp, int num_ep,
 178     unsigned char *buffer, int size)
 179 {
 180         unsigned char *buffer0 = buffer;
 181         struct usb_endpoint_descriptor *d;
 182         struct usb_host_endpoint *endpoint;
 183         int n, i, j, retval;
 184
 185         d = (struct usb_endpoint_descriptor *) buffer;
 186         buffer += d->bLength;
 187         size -= d->bLength;
 188
 189         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 190                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 191         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 192                 n = USB_DT_ENDPOINT_SIZE;
 193         else {
 194                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 195                     "invalid endpoint descriptor of length %d, skipping\n",
 196                     cfgno, inum, asnum, d->bLength);
 197                 goto skip_to_next_endpoint_or_interface_descriptor;
 198         }
 199
 200         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 201         if (i >= 16 || i == 0) {
 202                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 203                     "invalid endpoint with address 0x%X, skipping\n",
 204                     cfgno, inum, asnum, d->bEndpointAddress);
 205                 goto skip_to_next_endpoint_or_interface_descriptor;
 206         }
 207
 208         /* Only store as many endpoints as we have room for */
 209         if (ifp->desc.bNumEndpoints >= num_ep)
 210                 goto skip_to_next_endpoint_or_interface_descriptor;
 211
 212         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 213         ++ifp->desc.bNumEndpoints;
 214
 215         memcpy(&endpoint->desc, d, n);
 216         INIT_LIST_HEAD(&endpoint->urb_list);
 217
 218         /* Fix up bInterval values outside the legal range. Use 32 ms if no
 219          * proper value can be guessed. */
 220         i = 0;          /* i = min, j = max, n = default */
 221         j = 255;
 222         if (usb_endpoint_xfer_int(d)) {
 223                 i = 1;
 224                 switch (to_usb_device(ddev)->speed) {
 225                 case USB_SPEED_SUPER_PLUS:
 226                 case USB_SPEED_SUPER:
 227                 case USB_SPEED_HIGH:
 228                         /* Many device manufacturers are using full-speed
 229                          * bInterval values in high-speed interrupt endpoint
 230                          * descriptors. Try to fix those and fall back to a
 231                          * 32 ms default value otherwise. */
 232                         n = fls(d->bInterval*8);
 233                         if (n == 0)
 234                                 n = 9;  /* 32 ms = 2^(9-1) uframes */
 235                         j = 16;
 236
 237                         /*
 238                          * Adjust bInterval for quirked devices.
 239                          * This quirk fixes bIntervals reported in
 240                          * linear microframes.
 241                          */
 242                         if (to_usb_device(ddev)->quirks &
 243                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 244                                 n = clamp(fls(d->bInterval), i, j);
 245                                 i = j = n;
 246                         }
 247                         break;
 248                 default:                /* USB_SPEED_FULL or _LOW */
 249                         /* For low-speed, 10 ms is the official minimum.
 250                          * But some "overclocked" devices might want faster
 251                          * polling so we'll allow it. */
 252                         n = 32;
 253                         break;
 254                 }
 255         } else if (usb_endpoint_xfer_isoc(d)) {
 256                 i = 1;
 257                 j = 16;
 258                 switch (to_usb_device(ddev)->speed) {
 259                 case USB_SPEED_HIGH:
 260                         n = 9;          /* 32 ms = 2^(9-1) uframes */
 261                         break;
 262                 default:                /* USB_SPEED_FULL */
 263                         n = 6;          /* 32 ms = 2^(6-1) frames */
 264                         break;
 265                 }
 266         }
 267         if (d->bInterval < i || d->bInterval > j) {
 268                 dev_warn(ddev, "config %d interface %d altsetting %d "
 269                     "endpoint 0x%X has an invalid bInterval %d, "
 270                     "changing to %d\n",
 271                     cfgno, inum, asnum,
 272                     d->bEndpointAddress, d->bInterval, n);
 273                 endpoint->desc.bInterval = n;
 274         }
 275
 276         /* Some buggy low-speed devices have Bulk endpoints, which is
 277          * explicitly forbidden by the USB spec.  In an attempt to make
 278          * them usable, we will try treating them as Interrupt endpoints.
 279          */
 280         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 281                         usb_endpoint_xfer_bulk(d)) {
 282                 dev_warn(ddev, "config %d interface %d altsetting %d "
 283                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 284                     cfgno, inum, asnum, d->bEndpointAddress);
 285                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 286                 endpoint->desc.bInterval = 1;
 287                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 288                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 289         }
 290
 291         /*
 292          * Some buggy high speed devices have bulk endpoints using
 293          * maxpacket sizes other than 512.  High speed HCDs may not
 294          * be able to handle that particular bug, so let's warn...
 295          */
 296         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 297                         && usb_endpoint_xfer_bulk(d)) {
 298                 unsigned maxp;
 299
 300                 maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
 301                 if (maxp != 512)
 302                         dev_warn(ddev, "config %d interface %d altsetting %d "
 303                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 304                                 cfgno, inum, asnum, d->bEndpointAddress,
 305                                 maxp);
 306         }
 307
 308         /* Parse a possible SuperSpeed endpoint companion descriptor */
 309         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 310                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 311                                 inum, asnum, endpoint, buffer, size);
 312
 313         /* Skip over any Class Specific or Vendor Specific descriptors;
 314          * find the next endpoint or interface descriptor */
 315         endpoint->extra = buffer;
 316         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 317                         USB_DT_INTERFACE, &n);
 318         endpoint->extralen = i;
 319         retval = buffer - buffer0 + i;
 320         if (n > 0)
 321                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 322                     n, plural(n), "endpoint");
 323         return retval;
 324
 325 skip_to_next_endpoint_or_interface_descriptor:
 326         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 327             USB_DT_INTERFACE, NULL);
 328         return buffer - buffer0 + i;
 329 }
 330
 331 void usb_release_interface_cache(struct kref *ref)
 332 {
 333         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 334         int j;
 335
 336         for (j = 0; j < intfc->num_altsetting; j++) {
 337                 struct usb_host_interface *alt = &intfc->altsetting[j];
 338
 339                 kfree(alt->endpoint);
 340                 kfree(alt->string);
 341         }
 342         kfree(intfc);
 343 }
 344
 345 static int usb_parse_interface(struct device *ddev, int cfgno,
 346     struct usb_host_config *config, unsigned char *buffer, int size,
 347     u8 inums[], u8 nalts[])
 348 {
 349         unsigned char *buffer0 = buffer;
 350         struct usb_interface_descriptor *d;
 351         int inum, asnum;
 352         struct usb_interface_cache *intfc;
 353         struct usb_host_interface *alt;
 354         int i, n;
 355         int len, retval;
 356         int num_ep, num_ep_orig;
 357
 358         d = (struct usb_interface_descriptor *) buffer;
 359         buffer += d->bLength;
 360         size -= d->bLength;
 361
 362         if (d->bLength < USB_DT_INTERFACE_SIZE)
 363                 goto skip_to_next_interface_descriptor;
 364
 365         /* Which interface entry is this? */
 366         intfc = NULL;
 367         inum = d->bInterfaceNumber;
 368         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 369                 if (inums[i] == inum) {
 370                         intfc = config->intf_cache[i];
 371                         break;
 372                 }
 373         }
 374         if (!intfc || intfc->num_altsetting >= nalts[i])
 375                 goto skip_to_next_interface_descriptor;
 376
 377         /* Check for duplicate altsetting entries */
 378         asnum = d->bAlternateSetting;
 379         for ((i = 0, alt = &intfc->altsetting[0]);
 380               i < intfc->num_altsetting;
 381              (++i, ++alt)) {
 382                 if (alt->desc.bAlternateSetting == asnum) {
 383                         dev_warn(ddev, "Duplicate descriptor for config %d "
 384                             "interface %d altsetting %d, skipping\n",
 385                             cfgno, inum, asnum);
 386                         goto skip_to_next_interface_descriptor;
 387                 }
 388         }
 389
 390         ++intfc->num_altsetting;
 391         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 392
 393         /* Skip over any Class Specific or Vendor Specific descriptors;
 394          * find the first endpoint or interface descriptor */
 395         alt->extra = buffer;
 396         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 397             USB_DT_INTERFACE, &n);
 398         alt->extralen = i;
 399         if (n > 0)
 400                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 401                     n, plural(n), "interface");
 402         buffer += i;
 403         size -= i;
 404
 405         /* Allocate space for the right(?) number of endpoints */
 406         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 407         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 408         if (num_ep > USB_MAXENDPOINTS) {
 409                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 410                     "altsetting %d: %d, using maximum allowed: %d\n",
 411                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 412                 num_ep = USB_MAXENDPOINTS;
 413         }
 414
 415         if (num_ep > 0) {
 416                 /* Can't allocate 0 bytes */
 417                 len = sizeof(struct usb_host_endpoint) * num_ep;
 418                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 419                 if (!alt->endpoint)
 420                         return -ENOMEM;
 421         }
 422
 423         /* Parse all the endpoint descriptors */
 424         n = 0;
 425         while (size > 0) {
 426                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 427                      == USB_DT_INTERFACE)
 428                         break;
 429                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 430                     num_ep, buffer, size);
 431                 if (retval < 0)
 432                         return retval;
 433                 ++n;
 434
 435                 buffer += retval;
 436                 size -= retval;
 437         }
 438
 439         if (n != num_ep_orig)
 440                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 441                     "endpoint descriptor%s, different from the interface "
 442                     "descriptor's value: %d\n",
 443                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 444         return buffer - buffer0;
 445
 446 skip_to_next_interface_descriptor:
 447         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 448             USB_DT_INTERFACE, NULL);
 449         return buffer - buffer0 + i;
 450 }
 451
 452 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 453     struct usb_host_config *config, unsigned char *buffer, int size)
 454 {
 455         struct device *ddev = &dev->dev;
 456         unsigned char *buffer0 = buffer;
 457         int cfgno;
 458         int nintf, nintf_orig;
 459         int i, j, n;
 460         struct usb_interface_cache *intfc;
 461         unsigned char *buffer2;
 462         int size2;
 463         struct usb_descriptor_header *header;
 464         int len, retval;
 465         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 466         unsigned iad_num = 0;
 467
 468         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 469         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 470             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 471             config->desc.bLength > size) {
 472                 dev_err(ddev, "invalid descriptor for config index %d: "
 473                     "type = 0x%X, length = %d\n", cfgidx,
 474                     config->desc.bDescriptorType, config->desc.bLength);
 475                 return -EINVAL;
 476         }
 477         cfgno = config->desc.bConfigurationValue;
 478
 479         buffer += config->desc.bLength;
 480         size -= config->desc.bLength;
 481
 482         nintf = nintf_orig = config->desc.bNumInterfaces;
 483         if (nintf > USB_MAXINTERFACES) {
 484                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 485                     "using maximum allowed: %d\n",
 486                     cfgno, nintf, USB_MAXINTERFACES);
 487                 nintf = USB_MAXINTERFACES;
 488         }
 489
 490         /* Go through the descriptors, checking their length and counting the
 491          * number of altsettings for each interface */
 492         n = 0;
 493         for ((buffer2 = buffer, size2 = size);
 494               size2 > 0;
 495              (buffer2 += header->bLength, size2 -= header->bLength)) {
 496
 497                 if (size2 < sizeof(struct usb_descriptor_header)) {
 498                         dev_warn(ddev, "config %d descriptor has %d excess "
 499                             "byte%s, ignoring\n",
 500                             cfgno, size2, plural(size2));
 501                         break;
 502                 }
 503
 504                 header = (struct usb_descriptor_header *) buffer2;
 505                 if ((header->bLength > size2) || (header->bLength < 2)) {
 506                         dev_warn(ddev, "config %d has an invalid descriptor "
 507                             "of length %d, skipping remainder of the config\n",
 508                             cfgno, header->bLength);
 509                         break;
 510                 }
 511
 512                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 513                         struct usb_interface_descriptor *d;
 514                         int inum;
 515
 516                         d = (struct usb_interface_descriptor *) header;
 517                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 518                                 dev_warn(ddev, "config %d has an invalid "
 519                                     "interface descriptor of length %d, "
 520                                     "skipping\n", cfgno, d->bLength);
 521                                 continue;
 522                         }
 523
 524                         inum = d->bInterfaceNumber;
 525
 526                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 527                             n >= nintf_orig) {
 528                                 dev_warn(ddev, "config %d has more interface "
 529                                     "descriptors, than it declares in "
 530                                     "bNumInterfaces, ignoring interface "
 531                                     "number: %d\n", cfgno, inum);
 532                                 continue;
 533                         }
 534
 535                         if (inum >= nintf_orig)
 536                                 dev_warn(ddev, "config %d has an invalid "
 537                                     "interface number: %d but max is %d\n",
 538                                     cfgno, inum, nintf_orig - 1);
 539
 540                         /* Have we already encountered this interface?
 541                          * Count its altsettings */
 542                         for (i = 0; i < n; ++i) {
 543                                 if (inums[i] == inum)
 544                                         break;
 545                         }
 546                         if (i < n) {
 547                                 if (nalts[i] < 255)
 548                                         ++nalts[i];
 549                         } else if (n < USB_MAXINTERFACES) {
 550                                 inums[n] = inum;
 551                                 nalts[n] = 1;
 552                                 ++n;
 553                         }
 554
 555                 } else if (header->bDescriptorType ==
 556                                 USB_DT_INTERFACE_ASSOCIATION) {
 557                         if (iad_num == USB_MAXIADS) {
 558                                 dev_warn(ddev, "found more Interface "
 559                                                "Association Descriptors "
 560                                                "than allocated for in "
 561                                                "configuration %d\n", cfgno);
 562                         } else {
 563                                 config->intf_assoc[iad_num] =
 564                                         (struct usb_interface_assoc_descriptor
 565                                         *)header;
 566                                 iad_num++;
 567                         }
 568
 569                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 570                             header->bDescriptorType == USB_DT_CONFIG)
 571                         dev_warn(ddev, "config %d contains an unexpected "
 572                             "descriptor of type 0x%X, skipping\n",
 573                             cfgno, header->bDescriptorType);
 574
 575         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 576         size = buffer2 - buffer;
 577         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 578
 579         if (n != nintf)
 580                 dev_warn(ddev, "config %d has %d interface%s, different from "
 581                     "the descriptor's value: %d\n",
 582                     cfgno, n, plural(n), nintf_orig);
 583         else if (n == 0)
 584                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 585         config->desc.bNumInterfaces = nintf = n;
 586
 587         /* Check for missing interface numbers */
 588         for (i = 0; i < nintf; ++i) {
 589                 for (j = 0; j < nintf; ++j) {
 590                         if (inums[j] == i)
 591                                 break;
 592                 }
 593                 if (j >= nintf)
 594                         dev_warn(ddev, "config %d has no interface number "
 595                             "%d\n", cfgno, i);
 596         }
 597
 598         /* Allocate the usb_interface_caches and altsetting arrays */
 599         for (i = 0; i < nintf; ++i) {
 600                 j = nalts[i];
 601                 if (j > USB_MAXALTSETTING) {
 602                         dev_warn(ddev, "too many alternate settings for "
 603                             "config %d interface %d: %d, "
 604                             "using maximum allowed: %d\n",
 605                             cfgno, inums[i], j, USB_MAXALTSETTING);
 606                         nalts[i] = j = USB_MAXALTSETTING;
 607                 }
 608
 609                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 610                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 611                 if (!intfc)
 612                         return -ENOMEM;
 613                 kref_init(&intfc->ref);
 614         }
 615
 616         /* FIXME: parse the BOS descriptor */
 617
 618         /* Skip over any Class Specific or Vendor Specific descriptors;
 619          * find the first interface descriptor */
 620         config->extra = buffer;
 621         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 622             USB_DT_INTERFACE, &n);
 623         config->extralen = i;
 624         if (n > 0)
 625                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 626                     n, plural(n), "configuration");
 627         buffer += i;
 628         size -= i;
 629
 630         /* Parse all the interface/altsetting descriptors */
 631         while (size > 0) {
 632                 retval = usb_parse_interface(ddev, cfgno, config,
 633                     buffer, size, inums, nalts);
 634                 if (retval < 0)
 635                         return retval;
 636
 637                 buffer += retval;
 638                 size -= retval;
 639         }
 640
 641         /* Check for missing altsettings */
 642         for (i = 0; i < nintf; ++i) {
 643                 intfc = config->intf_cache[i];
 644                 for (j = 0; j < intfc->num_altsetting; ++j) {
 645                         for (n = 0; n < intfc->num_altsetting; ++n) {
 646                                 if (intfc->altsetting[n].desc.
 647                                     bAlternateSetting == j)
 648                                         break;
 649                         }
 650                         if (n >= intfc->num_altsetting)
 651                                 dev_warn(ddev, "config %d interface %d has no "
 652                                     "altsetting %d\n", cfgno, inums[i], j);
 653                 }
 654         }
 655
 656         return 0;
 657 }
 658
 659 /* hub-only!! ... and only exported for reset/reinit path.
 660  * otherwise used internally on disconnect/destroy path
 661  */
 662 void usb_destroy_configuration(struct usb_device *dev)
 663 {
 664         int c, i;
 665
 666         if (!dev->config)
 667                 return;
 668
 669         if (dev->rawdescriptors) {
 670                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 671                         kfree(dev->rawdescriptors[i]);
 672
 673                 kfree(dev->rawdescriptors);
 674                 dev->rawdescriptors = NULL;
 675         }
 676
 677         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 678                 struct usb_host_config *cf = &dev->config[c];
 679
 680                 kfree(cf->string);
 681                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 682                         if (cf->intf_cache[i])
 683                                 kref_put(&cf->intf_cache[i]->ref,
 684                                           usb_release_interface_cache);
 685                 }
 686         }
 687         kfree(dev->config);
 688         dev->config = NULL;
 689 }
 690
 691
 692 /*
 693  * Get the USB config descriptors, cache and parse'em
 694  *
 695  * hub-only!! ... and only in reset path, or usb_new_device()
 696  * (used by real hubs and virtual root hubs)
 697  */
 698 int usb_get_configuration(struct usb_device *dev)
 699 {
 700         struct device *ddev = &dev->dev;
 701         int ncfg = dev->descriptor.bNumConfigurations;
 702         int result = 0;
 703         unsigned int cfgno, length;
 704         unsigned char *bigbuffer;
 705         struct usb_config_descriptor *desc;
 706
 707         cfgno = 0;
 708         result = -ENOMEM;
 709         if (ncfg > USB_MAXCONFIG) {
 710                 dev_warn(ddev, "too many configurations: %d, "
 711                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 712                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 713         }
 714
 715         if (ncfg < 1) {
 716                 dev_err(ddev, "no configurations\n");
 717                 return -EINVAL;
 718         }
 719
 720         length = ncfg * sizeof(struct usb_host_config);
 721         dev->config = kzalloc(length, GFP_KERNEL);
 722         if (!dev->config)
 723                 goto err2;
 724
 725         length = ncfg * sizeof(char *);
 726         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 727         if (!dev->rawdescriptors)
 728                 goto err2;
 729
 730         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 731         if (!desc)
 732                 goto err2;
 733
 734         result = 0;
 735         for (; cfgno < ncfg; cfgno++) {
 736                 /* We grab just the first descriptor so we know how long
 737                  * the whole configuration is */
 738                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 739                     desc, USB_DT_CONFIG_SIZE);
 740                 if (result < 0) {
 741                         dev_err(ddev, "unable to read config index %d "
 742                             "descriptor/%s: %d\n", cfgno, "start", result);
 743                         if (result != -EPIPE)
 744                                 goto err;
 745                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 746                         dev->descriptor.bNumConfigurations = cfgno;
 747                         break;
 748                 } else if (result < 4) {
 749                         dev_err(ddev, "config index %d descriptor too short "
 750                             "(expected %i, got %i)\n", cfgno,
 751                             USB_DT_CONFIG_SIZE, result);
 752                         result = -EINVAL;
 753                         goto err;
 754                 }
 755                 length = max((int) le16_to_cpu(desc->wTotalLength),
 756                     USB_DT_CONFIG_SIZE);
 757
 758                 /* Now that we know the length, get the whole thing */
 759                 bigbuffer = kmalloc(length, GFP_KERNEL);
 760                 if (!bigbuffer) {
 761                         result = -ENOMEM;
 762                         goto err;
 763                 }
 764
 765                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 766                         msleep(100);
 767
 768                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 769                     bigbuffer, length);
 770                 if (result < 0) {
 771                         dev_err(ddev, "unable to read config index %d "
 772                             "descriptor/%s\n", cfgno, "all");
 773                         kfree(bigbuffer);
 774                         goto err;
 775                 }
 776                 if (result < length) {
 777                         dev_warn(ddev, "config index %d descriptor too short "
 778                             "(expected %i, got %i)\n", cfgno, length, result);
 779                         length = result;
 780                 }
 781
 782                 dev->rawdescriptors[cfgno] = bigbuffer;
 783
 784                 result = usb_parse_configuration(dev, cfgno,
 785                     &dev->config[cfgno], bigbuffer, length);
 786                 if (result < 0) {
 787                         ++cfgno;
 788                         goto err;
 789                 }
 790         }
 791         result = 0;
 792
 793 err:
 794         kfree(desc);
 795         dev->descriptor.bNumConfigurations = cfgno;
 796 err2:
 797         if (result == -ENOMEM)
 798                 dev_err(ddev, "out of memory\n");
 799         return result;
 800 }
 801
 802 void usb_release_bos_descriptor(struct usb_device *dev)
 803 {
 804         if (dev->bos) {
 805                 kfree(dev->bos->desc);
 806                 kfree(dev->bos);
 807                 dev->bos = NULL;
 808         }
 809 }
 810
 811 /* Get BOS descriptor set */
 812 int usb_get_bos_descriptor(struct usb_device *dev)
 813 {
 814         struct device *ddev = &dev->dev;
 815         struct usb_bos_descriptor *bos;
 816         struct usb_dev_cap_header *cap;
 817         unsigned char *buffer;
 818         int length, total_len, num, i;
 819         int ret;
 820
 821         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 822         if (!bos)
 823                 return -ENOMEM;
 824
 825         /* Get BOS descriptor */
 826         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 827         if (ret < USB_DT_BOS_SIZE) {
 828                 dev_err(ddev, "unable to get BOS descriptor\n");
 829                 if (ret >= 0)
 830                         ret = -ENOMSG;
 831                 kfree(bos);
 832                 return ret;
 833         }
 834
 835         length = bos->bLength;
 836         total_len = le16_to_cpu(bos->wTotalLength);
 837         num = bos->bNumDeviceCaps;
 838         kfree(bos);
 839         if (total_len < length)
 840                 return -EINVAL;
 841
 842         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 843         if (!dev->bos)
 844                 return -ENOMEM;
 845
 846         /* Now let's get the whole BOS descriptor set */
 847         buffer = kzalloc(total_len, GFP_KERNEL);
 848         if (!buffer) {
 849                 ret = -ENOMEM;
 850                 goto err;
 851         }
 852         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 853
 854         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 855         if (ret < total_len) {
 856                 dev_err(ddev, "unable to get BOS descriptor set\n");
 857                 if (ret >= 0)
 858                         ret = -ENOMSG;
 859                 goto err;
 860         }
 861         total_len -= length;
 862
 863         for (i = 0; i < num; i++) {
 864                 buffer += length;
 865                 cap = (struct usb_dev_cap_header *)buffer;
 866                 length = cap->bLength;
 867
 868                 if (total_len < length)
 869                         break;
 870                 total_len -= length;
 871
 872                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 873                         dev_warn(ddev, "descriptor type invalid, skip\n");
 874                         continue;
 875                 }
 876
 877                 switch (cap->bDevCapabilityType) {
 878                 case USB_CAP_TYPE_WIRELESS_USB:
 879                         /* Wireless USB cap descriptor is handled by wusb */
 880                         break;
 881                 case USB_CAP_TYPE_EXT:
 882                         dev->bos->ext_cap =
 883                                 (struct usb_ext_cap_descriptor *)buffer;
 884                         break;
 885                 case USB_SS_CAP_TYPE:
 886                         dev->bos->ss_cap =
 887                                 (struct usb_ss_cap_descriptor *)buffer;
 888                         break;
 889                 case USB_SSP_CAP_TYPE:
 890                         dev->bos->ssp_cap =
 891                                 (struct usb_ssp_cap_descriptor *)buffer;
 892                         break;
 893                 case CONTAINER_ID_TYPE:
 894                         dev->bos->ss_id =
 895                                 (struct usb_ss_container_id_descriptor *)buffer;
 896                         break;
 897                 case USB_PTM_CAP_TYPE:
 898                         dev->bos->ptm_cap =
 899                                 (struct usb_ptm_cap_descriptor *)buffer;
 900                 default:
 901                         break;
 902                 }
 903         }
 904
 905         return 0;
 906
 907 err:
 908         usb_release_bos_descriptor(dev);
 909         return ret;
 910 }