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 const unsigned short low_speed_maxpacket_maxes[4] = {
 175         [USB_ENDPOINT_XFER_CONTROL] = 8,
 176         [USB_ENDPOINT_XFER_ISOC] = 0,
 177         [USB_ENDPOINT_XFER_BULK] = 0,
 178         [USB_ENDPOINT_XFER_INT] = 8,
 179 };
 180 static const unsigned short full_speed_maxpacket_maxes[4] = {
 181         [USB_ENDPOINT_XFER_CONTROL] = 64,
 182         [USB_ENDPOINT_XFER_ISOC] = 1023,
 183         [USB_ENDPOINT_XFER_BULK] = 64,
 184         [USB_ENDPOINT_XFER_INT] = 64,
 185 };
 186 static const unsigned short high_speed_maxpacket_maxes[4] = {
 187         [USB_ENDPOINT_XFER_CONTROL] = 64,
 188         [USB_ENDPOINT_XFER_ISOC] = 1024,
 189         [USB_ENDPOINT_XFER_BULK] = 512,
 190         [USB_ENDPOINT_XFER_INT] = 1024,
 191 };
 192 static const unsigned short super_speed_maxpacket_maxes[4] = {
 193         [USB_ENDPOINT_XFER_CONTROL] = 512,
 194         [USB_ENDPOINT_XFER_ISOC] = 1024,
 195         [USB_ENDPOINT_XFER_BULK] = 1024,
 196         [USB_ENDPOINT_XFER_INT] = 1024,
 197 };
 198
 199 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 200     int asnum, struct usb_host_interface *ifp, int num_ep,
 201     unsigned char *buffer, int size)
 202 {
 203         unsigned char *buffer0 = buffer;
 204         struct usb_endpoint_descriptor *d;
 205         struct usb_host_endpoint *endpoint;
 206         int n, i, j, retval;
 207         unsigned int maxp;
 208         const unsigned short *maxpacket_maxes;
 209
 210         d = (struct usb_endpoint_descriptor *) buffer;
 211         buffer += d->bLength;
 212         size -= d->bLength;
 213
 214         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 215                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 216         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 217                 n = USB_DT_ENDPOINT_SIZE;
 218         else {
 219                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 220                     "invalid endpoint descriptor of length %d, skipping\n",
 221                     cfgno, inum, asnum, d->bLength);
 222                 goto skip_to_next_endpoint_or_interface_descriptor;
 223         }
 224
 225         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 226         if (i >= 16 || i == 0) {
 227                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 228                     "invalid endpoint with address 0x%X, skipping\n",
 229                     cfgno, inum, asnum, d->bEndpointAddress);
 230                 goto skip_to_next_endpoint_or_interface_descriptor;
 231         }
 232
 233         /* Only store as many endpoints as we have room for */
 234         if (ifp->desc.bNumEndpoints >= num_ep)
 235                 goto skip_to_next_endpoint_or_interface_descriptor;
 236
 237         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 238         ++ifp->desc.bNumEndpoints;
 239
 240         memcpy(&endpoint->desc, d, n);
 241         INIT_LIST_HEAD(&endpoint->urb_list);
 242
 243         /* Fix up bInterval values outside the legal range. Use 32 ms if no
 244          * proper value can be guessed. */
 245         i = 0;          /* i = min, j = max, n = default */
 246         j = 255;
 247         if (usb_endpoint_xfer_int(d)) {
 248                 i = 1;
 249                 switch (to_usb_device(ddev)->speed) {
 250                 case USB_SPEED_SUPER_PLUS:
 251                 case USB_SPEED_SUPER:
 252                 case USB_SPEED_HIGH:
 253                         /* Many device manufacturers are using full-speed
 254                          * bInterval values in high-speed interrupt endpoint
 255                          * descriptors. Try to fix those and fall back to a
 256                          * 32 ms default value otherwise. */
 257                         n = fls(d->bInterval*8);
 258                         if (n == 0)
 259                                 n = 9;  /* 32 ms = 2^(9-1) uframes */
 260                         j = 16;
 261
 262                         /*
 263                          * Adjust bInterval for quirked devices.
 264                          * This quirk fixes bIntervals reported in
 265                          * linear microframes.
 266                          */
 267                         if (to_usb_device(ddev)->quirks &
 268                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 269                                 n = clamp(fls(d->bInterval), i, j);
 270                                 i = j = n;
 271                         }
 272                         break;
 273                 default:                /* USB_SPEED_FULL or _LOW */
 274                         /* For low-speed, 10 ms is the official minimum.
 275                          * But some "overclocked" devices might want faster
 276                          * polling so we'll allow it. */
 277                         n = 32;
 278                         break;
 279                 }
 280         } else if (usb_endpoint_xfer_isoc(d)) {
 281                 i = 1;
 282                 j = 16;
 283                 switch (to_usb_device(ddev)->speed) {
 284                 case USB_SPEED_HIGH:
 285                         n = 9;          /* 32 ms = 2^(9-1) uframes */
 286                         break;
 287                 default:                /* USB_SPEED_FULL */
 288                         n = 6;          /* 32 ms = 2^(6-1) frames */
 289                         break;
 290                 }
 291         }
 292         if (d->bInterval < i || d->bInterval > j) {
 293                 dev_warn(ddev, "config %d interface %d altsetting %d "
 294                     "endpoint 0x%X has an invalid bInterval %d, "
 295                     "changing to %d\n",
 296                     cfgno, inum, asnum,
 297                     d->bEndpointAddress, d->bInterval, n);
 298                 endpoint->desc.bInterval = n;
 299         }
 300
 301         /* Some buggy low-speed devices have Bulk endpoints, which is
 302          * explicitly forbidden by the USB spec.  In an attempt to make
 303          * them usable, we will try treating them as Interrupt endpoints.
 304          */
 305         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 306                         usb_endpoint_xfer_bulk(d)) {
 307                 dev_warn(ddev, "config %d interface %d altsetting %d "
 308                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 309                     cfgno, inum, asnum, d->bEndpointAddress);
 310                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 311                 endpoint->desc.bInterval = 1;
 312                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 313                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 314         }
 315
 316         /* Validate the wMaxPacketSize field */
 317         maxp = usb_endpoint_maxp(&endpoint->desc);
 318
 319         /* Find the highest legal maxpacket size for this endpoint */
 320         i = 0;          /* additional transactions per microframe */
 321         switch (to_usb_device(ddev)->speed) {
 322         case USB_SPEED_LOW:
 323                 maxpacket_maxes = low_speed_maxpacket_maxes;
 324                 break;
 325         case USB_SPEED_FULL:
 326                 maxpacket_maxes = full_speed_maxpacket_maxes;
 327                 break;
 328         case USB_SPEED_HIGH:
 329                 /* Bits 12..11 are allowed only for HS periodic endpoints */
 330                 if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 331                         i = maxp & (BIT(12) | BIT(11));
 332                         maxp &= ~i;
 333                 }
 334                 /* fallthrough */
 335         default:
 336                 maxpacket_maxes = high_speed_maxpacket_maxes;
 337                 break;
 338         case USB_SPEED_SUPER:
 339         case USB_SPEED_SUPER_PLUS:
 340                 maxpacket_maxes = super_speed_maxpacket_maxes;
 341                 break;
 342         }
 343         j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 344
 345         if (maxp > j) {
 346                 dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 347                     cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 348                 maxp = j;
 349                 endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 350         }
 351
 352         /*
 353          * Some buggy high speed devices have bulk endpoints using
 354          * maxpacket sizes other than 512.  High speed HCDs may not
 355          * be able to handle that particular bug, so let's warn...
 356          */
 357         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 358                         && usb_endpoint_xfer_bulk(d)) {
 359                 if (maxp != 512)
 360                         dev_warn(ddev, "config %d interface %d altsetting %d "
 361                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 362                                 cfgno, inum, asnum, d->bEndpointAddress,
 363                                 maxp);
 364         }
 365
 366         /* Parse a possible SuperSpeed endpoint companion descriptor */
 367         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 368                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 369                                 inum, asnum, endpoint, buffer, size);
 370
 371         /* Skip over any Class Specific or Vendor Specific descriptors;
 372          * find the next endpoint or interface descriptor */
 373         endpoint->extra = buffer;
 374         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 375                         USB_DT_INTERFACE, &n);
 376         endpoint->extralen = i;
 377         retval = buffer - buffer0 + i;
 378         if (n > 0)
 379                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 380                     n, plural(n), "endpoint");
 381         return retval;
 382
 383 skip_to_next_endpoint_or_interface_descriptor:
 384         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 385             USB_DT_INTERFACE, NULL);
 386         return buffer - buffer0 + i;
 387 }
 388
 389 void usb_release_interface_cache(struct kref *ref)
 390 {
 391         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 392         int j;
 393
 394         for (j = 0; j < intfc->num_altsetting; j++) {
 395                 struct usb_host_interface *alt = &intfc->altsetting[j];
 396
 397                 kfree(alt->endpoint);
 398                 kfree(alt->string);
 399         }
 400         kfree(intfc);
 401 }
 402
 403 static int usb_parse_interface(struct device *ddev, int cfgno,
 404     struct usb_host_config *config, unsigned char *buffer, int size,
 405     u8 inums[], u8 nalts[])
 406 {
 407         unsigned char *buffer0 = buffer;
 408         struct usb_interface_descriptor *d;
 409         int inum, asnum;
 410         struct usb_interface_cache *intfc;
 411         struct usb_host_interface *alt;
 412         int i, n;
 413         int len, retval;
 414         int num_ep, num_ep_orig;
 415
 416         d = (struct usb_interface_descriptor *) buffer;
 417         buffer += d->bLength;
 418         size -= d->bLength;
 419
 420         if (d->bLength < USB_DT_INTERFACE_SIZE)
 421                 goto skip_to_next_interface_descriptor;
 422
 423         /* Which interface entry is this? */
 424         intfc = NULL;
 425         inum = d->bInterfaceNumber;
 426         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 427                 if (inums[i] == inum) {
 428                         intfc = config->intf_cache[i];
 429                         break;
 430                 }
 431         }
 432         if (!intfc || intfc->num_altsetting >= nalts[i])
 433                 goto skip_to_next_interface_descriptor;
 434
 435         /* Check for duplicate altsetting entries */
 436         asnum = d->bAlternateSetting;
 437         for ((i = 0, alt = &intfc->altsetting[0]);
 438               i < intfc->num_altsetting;
 439              (++i, ++alt)) {
 440                 if (alt->desc.bAlternateSetting == asnum) {
 441                         dev_warn(ddev, "Duplicate descriptor for config %d "
 442                             "interface %d altsetting %d, skipping\n",
 443                             cfgno, inum, asnum);
 444                         goto skip_to_next_interface_descriptor;
 445                 }
 446         }
 447
 448         ++intfc->num_altsetting;
 449         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 450
 451         /* Skip over any Class Specific or Vendor Specific descriptors;
 452          * find the first endpoint or interface descriptor */
 453         alt->extra = buffer;
 454         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 455             USB_DT_INTERFACE, &n);
 456         alt->extralen = i;
 457         if (n > 0)
 458                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 459                     n, plural(n), "interface");
 460         buffer += i;
 461         size -= i;
 462
 463         /* Allocate space for the right(?) number of endpoints */
 464         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 465         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 466         if (num_ep > USB_MAXENDPOINTS) {
 467                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 468                     "altsetting %d: %d, using maximum allowed: %d\n",
 469                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 470                 num_ep = USB_MAXENDPOINTS;
 471         }
 472
 473         if (num_ep > 0) {
 474                 /* Can't allocate 0 bytes */
 475                 len = sizeof(struct usb_host_endpoint) * num_ep;
 476                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 477                 if (!alt->endpoint)
 478                         return -ENOMEM;
 479         }
 480
 481         /* Parse all the endpoint descriptors */
 482         n = 0;
 483         while (size > 0) {
 484                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 485                      == USB_DT_INTERFACE)
 486                         break;
 487                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 488                     num_ep, buffer, size);
 489                 if (retval < 0)
 490                         return retval;
 491                 ++n;
 492
 493                 buffer += retval;
 494                 size -= retval;
 495         }
 496
 497         if (n != num_ep_orig)
 498                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 499                     "endpoint descriptor%s, different from the interface "
 500                     "descriptor's value: %d\n",
 501                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 502         return buffer - buffer0;
 503
 504 skip_to_next_interface_descriptor:
 505         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 506             USB_DT_INTERFACE, NULL);
 507         return buffer - buffer0 + i;
 508 }
 509
 510 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 511     struct usb_host_config *config, unsigned char *buffer, int size)
 512 {
 513         struct device *ddev = &dev->dev;
 514         unsigned char *buffer0 = buffer;
 515         int cfgno;
 516         int nintf, nintf_orig;
 517         int i, j, n;
 518         struct usb_interface_cache *intfc;
 519         unsigned char *buffer2;
 520         int size2;
 521         struct usb_descriptor_header *header;
 522         int len, retval;
 523         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 524         unsigned iad_num = 0;
 525
 526         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 527         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 528             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 529             config->desc.bLength > size) {
 530                 dev_err(ddev, "invalid descriptor for config index %d: "
 531                     "type = 0x%X, length = %d\n", cfgidx,
 532                     config->desc.bDescriptorType, config->desc.bLength);
 533                 return -EINVAL;
 534         }
 535         cfgno = config->desc.bConfigurationValue;
 536
 537         buffer += config->desc.bLength;
 538         size -= config->desc.bLength;
 539
 540         nintf = nintf_orig = config->desc.bNumInterfaces;
 541         if (nintf > USB_MAXINTERFACES) {
 542                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 543                     "using maximum allowed: %d\n",
 544                     cfgno, nintf, USB_MAXINTERFACES);
 545                 nintf = USB_MAXINTERFACES;
 546         }
 547
 548         /* Go through the descriptors, checking their length and counting the
 549          * number of altsettings for each interface */
 550         n = 0;
 551         for ((buffer2 = buffer, size2 = size);
 552               size2 > 0;
 553              (buffer2 += header->bLength, size2 -= header->bLength)) {
 554
 555                 if (size2 < sizeof(struct usb_descriptor_header)) {
 556                         dev_warn(ddev, "config %d descriptor has %d excess "
 557                             "byte%s, ignoring\n",
 558                             cfgno, size2, plural(size2));
 559                         break;
 560                 }
 561
 562                 header = (struct usb_descriptor_header *) buffer2;
 563                 if ((header->bLength > size2) || (header->bLength < 2)) {
 564                         dev_warn(ddev, "config %d has an invalid descriptor "
 565                             "of length %d, skipping remainder of the config\n",
 566                             cfgno, header->bLength);
 567                         break;
 568                 }
 569
 570                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 571                         struct usb_interface_descriptor *d;
 572                         int inum;
 573
 574                         d = (struct usb_interface_descriptor *) header;
 575                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 576                                 dev_warn(ddev, "config %d has an invalid "
 577                                     "interface descriptor of length %d, "
 578                                     "skipping\n", cfgno, d->bLength);
 579                                 continue;
 580                         }
 581
 582                         inum = d->bInterfaceNumber;
 583
 584                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 585                             n >= nintf_orig) {
 586                                 dev_warn(ddev, "config %d has more interface "
 587                                     "descriptors, than it declares in "
 588                                     "bNumInterfaces, ignoring interface "
 589                                     "number: %d\n", cfgno, inum);
 590                                 continue;
 591                         }
 592
 593                         if (inum >= nintf_orig)
 594                                 dev_warn(ddev, "config %d has an invalid "
 595                                     "interface number: %d but max is %d\n",
 596                                     cfgno, inum, nintf_orig - 1);
 597
 598                         /* Have we already encountered this interface?
 599                          * Count its altsettings */
 600                         for (i = 0; i < n; ++i) {
 601                                 if (inums[i] == inum)
 602                                         break;
 603                         }
 604                         if (i < n) {
 605                                 if (nalts[i] < 255)
 606                                         ++nalts[i];
 607                         } else if (n < USB_MAXINTERFACES) {
 608                                 inums[n] = inum;
 609                                 nalts[n] = 1;
 610                                 ++n;
 611                         }
 612
 613                 } else if (header->bDescriptorType ==
 614                                 USB_DT_INTERFACE_ASSOCIATION) {
 615                         if (iad_num == USB_MAXIADS) {
 616                                 dev_warn(ddev, "found more Interface "
 617                                                "Association Descriptors "
 618                                                "than allocated for in "
 619                                                "configuration %d\n", cfgno);
 620                         } else {
 621                                 config->intf_assoc[iad_num] =
 622                                         (struct usb_interface_assoc_descriptor
 623                                         *)header;
 624                                 iad_num++;
 625                         }
 626
 627                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 628                             header->bDescriptorType == USB_DT_CONFIG)
 629                         dev_warn(ddev, "config %d contains an unexpected "
 630                             "descriptor of type 0x%X, skipping\n",
 631                             cfgno, header->bDescriptorType);
 632
 633         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 634         size = buffer2 - buffer;
 635         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 636
 637         if (n != nintf)
 638                 dev_warn(ddev, "config %d has %d interface%s, different from "
 639                     "the descriptor's value: %d\n",
 640                     cfgno, n, plural(n), nintf_orig);
 641         else if (n == 0)
 642                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 643         config->desc.bNumInterfaces = nintf = n;
 644
 645         /* Check for missing interface numbers */
 646         for (i = 0; i < nintf; ++i) {
 647                 for (j = 0; j < nintf; ++j) {
 648                         if (inums[j] == i)
 649                                 break;
 650                 }
 651                 if (j >= nintf)
 652                         dev_warn(ddev, "config %d has no interface number "
 653                             "%d\n", cfgno, i);
 654         }
 655
 656         /* Allocate the usb_interface_caches and altsetting arrays */
 657         for (i = 0; i < nintf; ++i) {
 658                 j = nalts[i];
 659                 if (j > USB_MAXALTSETTING) {
 660                         dev_warn(ddev, "too many alternate settings for "
 661                             "config %d interface %d: %d, "
 662                             "using maximum allowed: %d\n",
 663                             cfgno, inums[i], j, USB_MAXALTSETTING);
 664                         nalts[i] = j = USB_MAXALTSETTING;
 665                 }
 666
 667                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 668                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 669                 if (!intfc)
 670                         return -ENOMEM;
 671                 kref_init(&intfc->ref);
 672         }
 673
 674         /* FIXME: parse the BOS descriptor */
 675
 676         /* Skip over any Class Specific or Vendor Specific descriptors;
 677          * find the first interface descriptor */
 678         config->extra = buffer;
 679         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 680             USB_DT_INTERFACE, &n);
 681         config->extralen = i;
 682         if (n > 0)
 683                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 684                     n, plural(n), "configuration");
 685         buffer += i;
 686         size -= i;
 687
 688         /* Parse all the interface/altsetting descriptors */
 689         while (size > 0) {
 690                 retval = usb_parse_interface(ddev, cfgno, config,
 691                     buffer, size, inums, nalts);
 692                 if (retval < 0)
 693                         return retval;
 694
 695                 buffer += retval;
 696                 size -= retval;
 697         }
 698
 699         /* Check for missing altsettings */
 700         for (i = 0; i < nintf; ++i) {
 701                 intfc = config->intf_cache[i];
 702                 for (j = 0; j < intfc->num_altsetting; ++j) {
 703                         for (n = 0; n < intfc->num_altsetting; ++n) {
 704                                 if (intfc->altsetting[n].desc.
 705                                     bAlternateSetting == j)
 706                                         break;
 707                         }
 708                         if (n >= intfc->num_altsetting)
 709                                 dev_warn(ddev, "config %d interface %d has no "
 710                                     "altsetting %d\n", cfgno, inums[i], j);
 711                 }
 712         }
 713
 714         return 0;
 715 }
 716
 717 /* hub-only!! ... and only exported for reset/reinit path.
 718  * otherwise used internally on disconnect/destroy path
 719  */
 720 void usb_destroy_configuration(struct usb_device *dev)
 721 {
 722         int c, i;
 723
 724         if (!dev->config)
 725                 return;
 726
 727         if (dev->rawdescriptors) {
 728                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 729                         kfree(dev->rawdescriptors[i]);
 730
 731                 kfree(dev->rawdescriptors);
 732                 dev->rawdescriptors = NULL;
 733         }
 734
 735         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 736                 struct usb_host_config *cf = &dev->config[c];
 737
 738                 kfree(cf->string);
 739                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 740                         if (cf->intf_cache[i])
 741                                 kref_put(&cf->intf_cache[i]->ref,
 742                                           usb_release_interface_cache);
 743                 }
 744         }
 745         kfree(dev->config);
 746         dev->config = NULL;
 747 }
 748
 749
 750 /*
 751  * Get the USB config descriptors, cache and parse'em
 752  *
 753  * hub-only!! ... and only in reset path, or usb_new_device()
 754  * (used by real hubs and virtual root hubs)
 755  */
 756 int usb_get_configuration(struct usb_device *dev)
 757 {
 758         struct device *ddev = &dev->dev;
 759         int ncfg = dev->descriptor.bNumConfigurations;
 760         int result = 0;
 761         unsigned int cfgno, length;
 762         unsigned char *bigbuffer;
 763         struct usb_config_descriptor *desc;
 764
 765         cfgno = 0;
 766         result = -ENOMEM;
 767         if (ncfg > USB_MAXCONFIG) {
 768                 dev_warn(ddev, "too many configurations: %d, "
 769                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 770                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 771         }
 772
 773         if (ncfg < 1) {
 774                 dev_err(ddev, "no configurations\n");
 775                 return -EINVAL;
 776         }
 777
 778         length = ncfg * sizeof(struct usb_host_config);
 779         dev->config = kzalloc(length, GFP_KERNEL);
 780         if (!dev->config)
 781                 goto err2;
 782
 783         length = ncfg * sizeof(char *);
 784         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 785         if (!dev->rawdescriptors)
 786                 goto err2;
 787
 788         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 789         if (!desc)
 790                 goto err2;
 791
 792         result = 0;
 793         for (; cfgno < ncfg; cfgno++) {
 794                 /* We grab just the first descriptor so we know how long
 795                  * the whole configuration is */
 796                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 797                     desc, USB_DT_CONFIG_SIZE);
 798                 if (result < 0) {
 799                         dev_err(ddev, "unable to read config index %d "
 800                             "descriptor/%s: %d\n", cfgno, "start", result);
 801                         if (result != -EPIPE)
 802                                 goto err;
 803                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 804                         dev->descriptor.bNumConfigurations = cfgno;
 805                         break;
 806                 } else if (result < 4) {
 807                         dev_err(ddev, "config index %d descriptor too short "
 808                             "(expected %i, got %i)\n", cfgno,
 809                             USB_DT_CONFIG_SIZE, result);
 810                         result = -EINVAL;
 811                         goto err;
 812                 }
 813                 length = max((int) le16_to_cpu(desc->wTotalLength),
 814                     USB_DT_CONFIG_SIZE);
 815
 816                 /* Now that we know the length, get the whole thing */
 817                 bigbuffer = kmalloc(length, GFP_KERNEL);
 818                 if (!bigbuffer) {
 819                         result = -ENOMEM;
 820                         goto err;
 821                 }
 822
 823                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 824                         msleep(100);
 825
 826                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 827                     bigbuffer, length);
 828                 if (result < 0) {
 829                         dev_err(ddev, "unable to read config index %d "
 830                             "descriptor/%s\n", cfgno, "all");
 831                         kfree(bigbuffer);
 832                         goto err;
 833                 }
 834                 if (result < length) {
 835                         dev_warn(ddev, "config index %d descriptor too short "
 836                             "(expected %i, got %i)\n", cfgno, length, result);
 837                         length = result;
 838                 }
 839
 840                 dev->rawdescriptors[cfgno] = bigbuffer;
 841
 842                 result = usb_parse_configuration(dev, cfgno,
 843                     &dev->config[cfgno], bigbuffer, length);
 844                 if (result < 0) {
 845                         ++cfgno;
 846                         goto err;
 847                 }
 848         }
 849         result = 0;
 850
 851 err:
 852         kfree(desc);
 853         dev->descriptor.bNumConfigurations = cfgno;
 854 err2:
 855         if (result == -ENOMEM)
 856                 dev_err(ddev, "out of memory\n");
 857         return result;
 858 }
 859
 860 void usb_release_bos_descriptor(struct usb_device *dev)
 861 {
 862         if (dev->bos) {
 863                 kfree(dev->bos->desc);
 864                 kfree(dev->bos);
 865                 dev->bos = NULL;
 866         }
 867 }
 868
 869 /* Get BOS descriptor set */
 870 int usb_get_bos_descriptor(struct usb_device *dev)
 871 {
 872         struct device *ddev = &dev->dev;
 873         struct usb_bos_descriptor *bos;
 874         struct usb_dev_cap_header *cap;
 875         unsigned char *buffer;
 876         int length, total_len, num, i;
 877         int ret;
 878
 879         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 880         if (!bos)
 881                 return -ENOMEM;
 882
 883         /* Get BOS descriptor */
 884         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 885         if (ret < USB_DT_BOS_SIZE) {
 886                 dev_err(ddev, "unable to get BOS descriptor\n");
 887                 if (ret >= 0)
 888                         ret = -ENOMSG;
 889                 kfree(bos);
 890                 return ret;
 891         }
 892
 893         length = bos->bLength;
 894         total_len = le16_to_cpu(bos->wTotalLength);
 895         num = bos->bNumDeviceCaps;
 896         kfree(bos);
 897         if (total_len < length)
 898                 return -EINVAL;
 899
 900         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 901         if (!dev->bos)
 902                 return -ENOMEM;
 903
 904         /* Now let's get the whole BOS descriptor set */
 905         buffer = kzalloc(total_len, GFP_KERNEL);
 906         if (!buffer) {
 907                 ret = -ENOMEM;
 908                 goto err;
 909         }
 910         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 911
 912         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 913         if (ret < total_len) {
 914                 dev_err(ddev, "unable to get BOS descriptor set\n");
 915                 if (ret >= 0)
 916                         ret = -ENOMSG;
 917                 goto err;
 918         }
 919         total_len -= length;
 920
 921         for (i = 0; i < num; i++) {
 922                 buffer += length;
 923                 cap = (struct usb_dev_cap_header *)buffer;
 924                 length = cap->bLength;
 925
 926                 if (total_len < length)
 927                         break;
 928                 total_len -= length;
 929
 930                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 931                         dev_warn(ddev, "descriptor type invalid, skip\n");
 932                         continue;
 933                 }
 934
 935                 switch (cap->bDevCapabilityType) {
 936                 case USB_CAP_TYPE_WIRELESS_USB:
 937                         /* Wireless USB cap descriptor is handled by wusb */
 938                         break;
 939                 case USB_CAP_TYPE_EXT:
 940                         dev->bos->ext_cap =
 941                                 (struct usb_ext_cap_descriptor *)buffer;
 942                         break;
 943                 case USB_SS_CAP_TYPE:
 944                         dev->bos->ss_cap =
 945                                 (struct usb_ss_cap_descriptor *)buffer;
 946                         break;
 947                 case USB_SSP_CAP_TYPE:
 948                         dev->bos->ssp_cap =
 949                                 (struct usb_ssp_cap_descriptor *)buffer;
 950                         break;
 951                 case CONTAINER_ID_TYPE:
 952                         dev->bos->ss_id =
 953                                 (struct usb_ss_container_id_descriptor *)buffer;
 954                         break;
 955                 case USB_PTM_CAP_TYPE:
 956                         dev->bos->ptm_cap =
 957                                 (struct usb_ptm_cap_descriptor *)buffer;
 958                 default:
 959                         break;
 960                 }
 961         }
 962
 963         return 0;
 964
 965 err:
 966         usb_release_bos_descriptor(dev);
 967         return ret;
 968 }