drivers/usb/core/config.c

   1 #include <linux/usb.h>
   2 #include <linux/usb/ch9.h>
   3 #include <linux/usb/hcd.h>
   4 #include <linux/usb/quirks.h>
   5 #include <linux/module.h>
   6 #include <linux/slab.h>
   7 #include <linux/device.h>
   8 #include <asm/byteorder.h>
   9 #include "usb.h"
  10
  11
  12 #define USB_MAXALTSETTING               128     /* Hard limit */
  13
  14 #define USB_MAXCONFIG                   8       /* Arbitrary limit */
  15
  16
  17 static inline const char *plural(int n)
  18 {
  19         return (n == 1 ? "" : "s");
  20 }
  21
  22 static int find_next_descriptor(unsigned char *buffer, int size,
  23     int dt1, int dt2, int *num_skipped)
  24 {
  25         struct usb_descriptor_header *h;
  26         int n = 0;
  27         unsigned char *buffer0 = buffer;
  28
  29         /* Find the next descriptor of type dt1 or dt2 */
  30         while (size > 0) {
  31                 h = (struct usb_descriptor_header *) buffer;
  32                 if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
  33                         break;
  34                 buffer += h->bLength;
  35                 size -= h->bLength;
  36                 ++n;
  37         }
  38
  39         /* Store the number of descriptors skipped and return the
  40          * number of bytes skipped */
  41         if (num_skipped)
  42                 *num_skipped = n;
  43         return buffer - buffer0;
  44 }
  45
  46 static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
  47                 int inum, int asnum, struct usb_host_endpoint *ep,
  48                 unsigned char *buffer, int size)
  49 {
  50         struct usb_ss_ep_comp_descriptor *desc;
  51         int max_tx;
  52
  53         /* The SuperSpeed endpoint companion descriptor is supposed to
  54          * be the first thing immediately following the endpoint descriptor.
  55          */
  56         desc = (struct usb_ss_ep_comp_descriptor *) buffer;
  57         if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
  58                         size < USB_DT_SS_EP_COMP_SIZE) {
  59                 dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
  60                                 " interface %d altsetting %d ep %d: "
  61                                 "using minimum values\n",
  62                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  63
  64                 /* Fill in some default values.
  65                  * Leave bmAttributes as zero, which will mean no streams for
  66                  * bulk, and isoc won't support multiple bursts of packets.
  67                  * With bursts of only one packet, and a Mult of 1, the max
  68                  * amount of data moved per endpoint service interval is one
  69                  * packet.
  70                  */
  71                 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
  72                 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
  73                 if (usb_endpoint_xfer_isoc(&ep->desc) ||
  74                                 usb_endpoint_xfer_int(&ep->desc))
  75                         ep->ss_ep_comp.wBytesPerInterval =
  76                                         ep->desc.wMaxPacketSize;
  77                 return;
  78         }
  79
  80         memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
  81
  82         /* Check the various values */
  83         if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
  84                 dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
  85                                 "config %d interface %d altsetting %d ep %d: "
  86                                 "setting to zero\n", desc->bMaxBurst,
  87                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  88                 ep->ss_ep_comp.bMaxBurst = 0;
  89         } else if (desc->bMaxBurst > 15) {
  90                 dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
  91                                 "config %d interface %d altsetting %d ep %d: "
  92                                 "setting to 15\n", desc->bMaxBurst,
  93                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  94                 ep->ss_ep_comp.bMaxBurst = 15;
  95         }
  96
  97         if ((usb_endpoint_xfer_control(&ep->desc) ||
  98                         usb_endpoint_xfer_int(&ep->desc)) &&
  99                                 desc->bmAttributes != 0) {
 100                 dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
 101                                 "config %d interface %d altsetting %d ep %d: "
 102                                 "setting to zero\n",
 103                                 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 104                                 desc->bmAttributes,
 105                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 106                 ep->ss_ep_comp.bmAttributes = 0;
 107         } else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 108                         desc->bmAttributes > 16) {
 109                 dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
 110                                 "config %d interface %d altsetting %d ep %d: "
 111                                 "setting to max\n",
 112                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 113                 ep->ss_ep_comp.bmAttributes = 16;
 114         } else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 115                    USB_SS_MULT(desc->bmAttributes) > 3) {
 116                 dev_warn(ddev, "Isoc endpoint has Mult of %d in "
 117                                 "config %d interface %d altsetting %d ep %d: "
 118                                 "setting to 3\n",
 119                                 USB_SS_MULT(desc->bmAttributes),
 120                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 121                 ep->ss_ep_comp.bmAttributes = 2;
 122         }
 123
 124         if (usb_endpoint_xfer_isoc(&ep->desc))
 125                 max_tx = (desc->bMaxBurst + 1) *
 126                         (USB_SS_MULT(desc->bmAttributes)) *
 127                         usb_endpoint_maxp(&ep->desc);
 128         else if (usb_endpoint_xfer_int(&ep->desc))
 129                 max_tx = usb_endpoint_maxp(&ep->desc) *
 130                         (desc->bMaxBurst + 1);
 131         else
 132                 max_tx = 999999;
 133         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 134                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 135                                 "config %d interface %d altsetting %d ep %d: "
 136                                 "setting to %d\n",
 137                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 138                                 le16_to_cpu(desc->wBytesPerInterval),
 139                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 140                                 max_tx);
 141                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 142         }
 143 }
 144
 145 static const unsigned short low_speed_maxpacket_maxes[4] = {
 146         [USB_ENDPOINT_XFER_CONTROL] = 8,
 147         [USB_ENDPOINT_XFER_ISOC] = 0,
 148         [USB_ENDPOINT_XFER_BULK] = 0,
 149         [USB_ENDPOINT_XFER_INT] = 8,
 150 };
 151 static const unsigned short full_speed_maxpacket_maxes[4] = {
 152         [USB_ENDPOINT_XFER_CONTROL] = 64,
 153         [USB_ENDPOINT_XFER_ISOC] = 1023,
 154         [USB_ENDPOINT_XFER_BULK] = 64,
 155         [USB_ENDPOINT_XFER_INT] = 64,
 156 };
 157 static const unsigned short high_speed_maxpacket_maxes[4] = {
 158         [USB_ENDPOINT_XFER_CONTROL] = 64,
 159         [USB_ENDPOINT_XFER_ISOC] = 1024,
 160
 161         /* Bulk should be 512, but some devices use 1024: we will warn below */
 162         [USB_ENDPOINT_XFER_BULK] = 1024,
 163         [USB_ENDPOINT_XFER_INT] = 1024,
 164 };
 165 static const unsigned short super_speed_maxpacket_maxes[4] = {
 166         [USB_ENDPOINT_XFER_CONTROL] = 512,
 167         [USB_ENDPOINT_XFER_ISOC] = 1024,
 168         [USB_ENDPOINT_XFER_BULK] = 1024,
 169         [USB_ENDPOINT_XFER_INT] = 1024,
 170 };
 171
 172 static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 173     int asnum, struct usb_host_interface *ifp, int num_ep,
 174     unsigned char *buffer, int size)
 175 {
 176         unsigned char *buffer0 = buffer;
 177         struct usb_endpoint_descriptor *d;
 178         struct usb_host_endpoint *endpoint;
 179         int n, i, j, retval;
 180         unsigned int maxp;
 181         const unsigned short *maxpacket_maxes;
 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         /* Check for duplicate endpoint addresses */
 211         for (i = 0; i < ifp->desc.bNumEndpoints; ++i) {
 212                 if (ifp->endpoint[i].desc.bEndpointAddress ==
 213                     d->bEndpointAddress) {
 214                         dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
 215                             cfgno, inum, asnum, d->bEndpointAddress);
 216                         goto skip_to_next_endpoint_or_interface_descriptor;
 217                 }
 218         }
 219
 220         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 221         ++ifp->desc.bNumEndpoints;
 222
 223         memcpy(&endpoint->desc, d, n);
 224         INIT_LIST_HEAD(&endpoint->urb_list);
 225
 226         /*
 227          * Fix up bInterval values outside the legal range.
 228          * Use 10 or 8 ms if no proper value can be guessed.
 229          */
 230         i = 0;          /* i = min, j = max, n = default */
 231         j = 255;
 232         if (usb_endpoint_xfer_int(d)) {
 233                 i = 1;
 234                 switch (to_usb_device(ddev)->speed) {
 235                 case USB_SPEED_SUPER_PLUS:
 236                 case USB_SPEED_SUPER:
 237                 case USB_SPEED_HIGH:
 238                         /*
 239                          * Many device manufacturers are using full-speed
 240                          * bInterval values in high-speed interrupt endpoint
 241                          * descriptors. Try to fix those and fall back to an
 242                          * 8-ms default value otherwise.
 243                          */
 244                         n = fls(d->bInterval*8);
 245                         if (n == 0)
 246                                 n = 7;  /* 8 ms = 2^(7-1) uframes */
 247                         j = 16;
 248
 249                         /*
 250                          * Adjust bInterval for quirked devices.
 251                          */
 252                         /*
 253                          * This quirk fixes bIntervals reported in ms.
 254                          */
 255                         if (to_usb_device(ddev)->quirks &
 256                                 USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 257                                 n = clamp(fls(d->bInterval) + 3, i, j);
 258                                 i = j = n;
 259                         }
 260                         /*
 261                          * This quirk fixes bIntervals reported in
 262                          * linear microframes.
 263                          */
 264                         if (to_usb_device(ddev)->quirks &
 265                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 266                                 n = clamp(fls(d->bInterval), i, j);
 267                                 i = j = n;
 268                         }
 269                         break;
 270                 default:                /* USB_SPEED_FULL or _LOW */
 271                         /*
 272                          * For low-speed, 10 ms is the official minimum.
 273                          * But some "overclocked" devices might want faster
 274                          * polling so we'll allow it.
 275                          */
 276                         n = 10;
 277                         break;
 278                 }
 279         } else if (usb_endpoint_xfer_isoc(d)) {
 280                 i = 1;
 281                 j = 16;
 282                 switch (to_usb_device(ddev)->speed) {
 283                 case USB_SPEED_HIGH:
 284                         n = 7;          /* 8 ms = 2^(7-1) uframes */
 285                         break;
 286                 default:                /* USB_SPEED_FULL */
 287                         n = 4;          /* 8 ms = 2^(4-1) frames */
 288                         break;
 289                 }
 290         }
 291         if (d->bInterval < i || d->bInterval > j) {
 292                 dev_warn(ddev, "config %d interface %d altsetting %d "
 293                     "endpoint 0x%X has an invalid bInterval %d, "
 294                     "changing to %d\n",
 295                     cfgno, inum, asnum,
 296                     d->bEndpointAddress, d->bInterval, n);
 297                 endpoint->desc.bInterval = n;
 298         }
 299
 300         /* Some buggy low-speed devices have Bulk endpoints, which is
 301          * explicitly forbidden by the USB spec.  In an attempt to make
 302          * them usable, we will try treating them as Interrupt endpoints.
 303          */
 304         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 305                         usb_endpoint_xfer_bulk(d)) {
 306                 dev_warn(ddev, "config %d interface %d altsetting %d "
 307                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 308                     cfgno, inum, asnum, d->bEndpointAddress);
 309                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 310                 endpoint->desc.bInterval = 1;
 311                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 312                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 313         }
 314
 315         /* Validate the wMaxPacketSize field */
 316         maxp = usb_endpoint_maxp(&endpoint->desc);
 317
 318         /* Find the highest legal maxpacket size for this endpoint */
 319         i = 0;          /* additional transactions per microframe */
 320         switch (to_usb_device(ddev)->speed) {
 321         case USB_SPEED_LOW:
 322                 maxpacket_maxes = low_speed_maxpacket_maxes;
 323                 break;
 324         case USB_SPEED_FULL:
 325                 maxpacket_maxes = full_speed_maxpacket_maxes;
 326                 break;
 327         case USB_SPEED_HIGH:
 328                 /* Bits 12..11 are allowed only for HS periodic endpoints */
 329                 if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 330                         i = maxp & (BIT(12) | BIT(11));
 331                         maxp &= ~i;
 332                 }
 333                 /* fallthrough */
 334         default:
 335                 maxpacket_maxes = high_speed_maxpacket_maxes;
 336                 break;
 337         case USB_SPEED_SUPER:
 338         case USB_SPEED_SUPER_PLUS:
 339                 maxpacket_maxes = super_speed_maxpacket_maxes;
 340                 break;
 341         }
 342         j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 343
 344         if (maxp > j) {
 345                 dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 346                     cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 347                 maxp = j;
 348                 endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 349         }
 350
 351         /*
 352          * Some buggy high speed devices have bulk endpoints using
 353          * maxpacket sizes other than 512.  High speed HCDs may not
 354          * be able to handle that particular bug, so let's warn...
 355          */
 356         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 357                         && usb_endpoint_xfer_bulk(d)) {
 358                 if (maxp != 512)
 359                         dev_warn(ddev, "config %d interface %d altsetting %d "
 360                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 361                                 cfgno, inum, asnum, d->bEndpointAddress,
 362                                 maxp);
 363         }
 364
 365         /* Parse a possible SuperSpeed endpoint companion descriptor */
 366         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 367                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 368                                 inum, asnum, endpoint, buffer, size);
 369
 370         /* Skip over any Class Specific or Vendor Specific descriptors;
 371          * find the next endpoint or interface descriptor */
 372         endpoint->extra = buffer;
 373         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 374                         USB_DT_INTERFACE, &n);
 375         endpoint->extralen = i;
 376         retval = buffer - buffer0 + i;
 377         if (n > 0)
 378                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 379                     n, plural(n), "endpoint");
 380         return retval;
 381
 382 skip_to_next_endpoint_or_interface_descriptor:
 383         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 384             USB_DT_INTERFACE, NULL);
 385         return buffer - buffer0 + i;
 386 }
 387
 388 void usb_release_interface_cache(struct kref *ref)
 389 {
 390         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 391         int j;
 392
 393         for (j = 0; j < intfc->num_altsetting; j++) {
 394                 struct usb_host_interface *alt = &intfc->altsetting[j];
 395
 396                 kfree(alt->endpoint);
 397                 kfree(alt->string);
 398         }
 399         kfree(intfc);
 400 }
 401
 402 static int usb_parse_interface(struct device *ddev, int cfgno,
 403     struct usb_host_config *config, unsigned char *buffer, int size,
 404     u8 inums[], u8 nalts[])
 405 {
 406         unsigned char *buffer0 = buffer;
 407         struct usb_interface_descriptor *d;
 408         int inum, asnum;
 409         struct usb_interface_cache *intfc;
 410         struct usb_host_interface *alt;
 411         int i, n;
 412         int len, retval;
 413         int num_ep, num_ep_orig;
 414
 415         d = (struct usb_interface_descriptor *) buffer;
 416         buffer += d->bLength;
 417         size -= d->bLength;
 418
 419         if (d->bLength < USB_DT_INTERFACE_SIZE)
 420                 goto skip_to_next_interface_descriptor;
 421
 422         /* Which interface entry is this? */
 423         intfc = NULL;
 424         inum = d->bInterfaceNumber;
 425         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 426                 if (inums[i] == inum) {
 427                         intfc = config->intf_cache[i];
 428                         break;
 429                 }
 430         }
 431         if (!intfc || intfc->num_altsetting >= nalts[i])
 432                 goto skip_to_next_interface_descriptor;
 433
 434         /* Check for duplicate altsetting entries */
 435         asnum = d->bAlternateSetting;
 436         for ((i = 0, alt = &intfc->altsetting[0]);
 437               i < intfc->num_altsetting;
 438              (++i, ++alt)) {
 439                 if (alt->desc.bAlternateSetting == asnum) {
 440                         dev_warn(ddev, "Duplicate descriptor for config %d "
 441                             "interface %d altsetting %d, skipping\n",
 442                             cfgno, inum, asnum);
 443                         goto skip_to_next_interface_descriptor;
 444                 }
 445         }
 446
 447         ++intfc->num_altsetting;
 448         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 449
 450         /* Skip over any Class Specific or Vendor Specific descriptors;
 451          * find the first endpoint or interface descriptor */
 452         alt->extra = buffer;
 453         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 454             USB_DT_INTERFACE, &n);
 455         alt->extralen = i;
 456         if (n > 0)
 457                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 458                     n, plural(n), "interface");
 459         buffer += i;
 460         size -= i;
 461
 462         /* Allocate space for the right(?) number of endpoints */
 463         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 464         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 465         if (num_ep > USB_MAXENDPOINTS) {
 466                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 467                     "altsetting %d: %d, using maximum allowed: %d\n",
 468                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 469                 num_ep = USB_MAXENDPOINTS;
 470         }
 471
 472         if (num_ep > 0) {
 473                 /* Can't allocate 0 bytes */
 474                 len = sizeof(struct usb_host_endpoint) * num_ep;
 475                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 476                 if (!alt->endpoint)
 477                         return -ENOMEM;
 478         }
 479
 480         /* Parse all the endpoint descriptors */
 481         n = 0;
 482         while (size > 0) {
 483                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 484                      == USB_DT_INTERFACE)
 485                         break;
 486                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 487                     num_ep, buffer, size);
 488                 if (retval < 0)
 489                         return retval;
 490                 ++n;
 491
 492                 buffer += retval;
 493                 size -= retval;
 494         }
 495
 496         if (n != num_ep_orig)
 497                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 498                     "endpoint descriptor%s, different from the interface "
 499                     "descriptor's value: %d\n",
 500                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 501         return buffer - buffer0;
 502
 503 skip_to_next_interface_descriptor:
 504         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 505             USB_DT_INTERFACE, NULL);
 506         return buffer - buffer0 + i;
 507 }
 508
 509 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 510     struct usb_host_config *config, unsigned char *buffer, int size)
 511 {
 512         struct device *ddev = &dev->dev;
 513         unsigned char *buffer0 = buffer;
 514         int cfgno;
 515         int nintf, nintf_orig;
 516         int i, j, n;
 517         struct usb_interface_cache *intfc;
 518         unsigned char *buffer2;
 519         int size2;
 520         struct usb_descriptor_header *header;
 521         int len, retval;
 522         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 523         unsigned iad_num = 0;
 524
 525         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 526         nintf = nintf_orig = config->desc.bNumInterfaces;
 527         config->desc.bNumInterfaces = 0;        // Adjusted later
 528
 529         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 530             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 531             config->desc.bLength > size) {
 532                 dev_err(ddev, "invalid descriptor for config index %d: "
 533                     "type = 0x%X, length = %d\n", cfgidx,
 534                     config->desc.bDescriptorType, config->desc.bLength);
 535                 return -EINVAL;
 536         }
 537         cfgno = config->desc.bConfigurationValue;
 538
 539         buffer += config->desc.bLength;
 540         size -= config->desc.bLength;
 541
 542         if (nintf > USB_MAXINTERFACES) {
 543                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 544                     "using maximum allowed: %d\n",
 545                     cfgno, nintf, USB_MAXINTERFACES);
 546                 nintf = USB_MAXINTERFACES;
 547         }
 548
 549         /* Go through the descriptors, checking their length and counting the
 550          * number of altsettings for each interface */
 551         n = 0;
 552         for ((buffer2 = buffer, size2 = size);
 553               size2 > 0;
 554              (buffer2 += header->bLength, size2 -= header->bLength)) {
 555
 556                 if (size2 < sizeof(struct usb_descriptor_header)) {
 557                         dev_warn(ddev, "config %d descriptor has %d excess "
 558                             "byte%s, ignoring\n",
 559                             cfgno, size2, plural(size2));
 560                         break;
 561                 }
 562
 563                 header = (struct usb_descriptor_header *) buffer2;
 564                 if ((header->bLength > size2) || (header->bLength < 2)) {
 565                         dev_warn(ddev, "config %d has an invalid descriptor "
 566                             "of length %d, skipping remainder of the config\n",
 567                             cfgno, header->bLength);
 568                         break;
 569                 }
 570
 571                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 572                         struct usb_interface_descriptor *d;
 573                         int inum;
 574
 575                         d = (struct usb_interface_descriptor *) header;
 576                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 577                                 dev_warn(ddev, "config %d has an invalid "
 578                                     "interface descriptor of length %d, "
 579                                     "skipping\n", cfgno, d->bLength);
 580                                 continue;
 581                         }
 582
 583                         inum = d->bInterfaceNumber;
 584
 585                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 586                             n >= nintf_orig) {
 587                                 dev_warn(ddev, "config %d has more interface "
 588                                     "descriptors, than it declares in "
 589                                     "bNumInterfaces, ignoring interface "
 590                                     "number: %d\n", cfgno, inum);
 591                                 continue;
 592                         }
 593
 594                         if (inum >= nintf_orig)
 595                                 dev_warn(ddev, "config %d has an invalid "
 596                                     "interface number: %d but max is %d\n",
 597                                     cfgno, inum, nintf_orig - 1);
 598
 599                         /* Have we already encountered this interface?
 600                          * Count its altsettings */
 601                         for (i = 0; i < n; ++i) {
 602                                 if (inums[i] == inum)
 603                                         break;
 604                         }
 605                         if (i < n) {
 606                                 if (nalts[i] < 255)
 607                                         ++nalts[i];
 608                         } else if (n < USB_MAXINTERFACES) {
 609                                 inums[n] = inum;
 610                                 nalts[n] = 1;
 611                                 ++n;
 612                         }
 613
 614                 } else if (header->bDescriptorType ==
 615                                 USB_DT_INTERFACE_ASSOCIATION) {
 616                         struct usb_interface_assoc_descriptor *d;
 617
 618                         d = (struct usb_interface_assoc_descriptor *)header;
 619                         if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
 620                                 dev_warn(ddev,
 621                                          "config %d has an invalid interface association descriptor of length %d, skipping\n",
 622                                          cfgno, d->bLength);
 623                                 continue;
 624                         }
 625
 626                         if (iad_num == USB_MAXIADS) {
 627                                 dev_warn(ddev, "found more Interface "
 628                                                "Association Descriptors "
 629                                                "than allocated for in "
 630                                                "configuration %d\n", cfgno);
 631                         } else {
 632                                 config->intf_assoc[iad_num] = d;
 633                                 iad_num++;
 634                         }
 635
 636                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 637                             header->bDescriptorType == USB_DT_CONFIG)
 638                         dev_warn(ddev, "config %d contains an unexpected "
 639                             "descriptor of type 0x%X, skipping\n",
 640                             cfgno, header->bDescriptorType);
 641
 642         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 643         size = buffer2 - buffer;
 644         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 645
 646         if (n != nintf)
 647                 dev_warn(ddev, "config %d has %d interface%s, different from "
 648                     "the descriptor's value: %d\n",
 649                     cfgno, n, plural(n), nintf_orig);
 650         else if (n == 0)
 651                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 652         config->desc.bNumInterfaces = nintf = n;
 653
 654         /* Check for missing interface numbers */
 655         for (i = 0; i < nintf; ++i) {
 656                 for (j = 0; j < nintf; ++j) {
 657                         if (inums[j] == i)
 658                                 break;
 659                 }
 660                 if (j >= nintf)
 661                         dev_warn(ddev, "config %d has no interface number "
 662                             "%d\n", cfgno, i);
 663         }
 664
 665         /* Allocate the usb_interface_caches and altsetting arrays */
 666         for (i = 0; i < nintf; ++i) {
 667                 j = nalts[i];
 668                 if (j > USB_MAXALTSETTING) {
 669                         dev_warn(ddev, "too many alternate settings for "
 670                             "config %d interface %d: %d, "
 671                             "using maximum allowed: %d\n",
 672                             cfgno, inums[i], j, USB_MAXALTSETTING);
 673                         nalts[i] = j = USB_MAXALTSETTING;
 674                 }
 675
 676                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 677                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 678                 if (!intfc)
 679                         return -ENOMEM;
 680                 kref_init(&intfc->ref);
 681         }
 682
 683         /* FIXME: parse the BOS descriptor */
 684
 685         /* Skip over any Class Specific or Vendor Specific descriptors;
 686          * find the first interface descriptor */
 687         config->extra = buffer;
 688         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 689             USB_DT_INTERFACE, &n);
 690         config->extralen = i;
 691         if (n > 0)
 692                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 693                     n, plural(n), "configuration");
 694         buffer += i;
 695         size -= i;
 696
 697         /* Parse all the interface/altsetting descriptors */
 698         while (size > 0) {
 699                 retval = usb_parse_interface(ddev, cfgno, config,
 700                     buffer, size, inums, nalts);
 701                 if (retval < 0)
 702                         return retval;
 703
 704                 buffer += retval;
 705                 size -= retval;
 706         }
 707
 708         /* Check for missing altsettings */
 709         for (i = 0; i < nintf; ++i) {
 710                 intfc = config->intf_cache[i];
 711                 for (j = 0; j < intfc->num_altsetting; ++j) {
 712                         for (n = 0; n < intfc->num_altsetting; ++n) {
 713                                 if (intfc->altsetting[n].desc.
 714                                     bAlternateSetting == j)
 715                                         break;
 716                         }
 717                         if (n >= intfc->num_altsetting)
 718                                 dev_warn(ddev, "config %d interface %d has no "
 719                                     "altsetting %d\n", cfgno, inums[i], j);
 720                 }
 721         }
 722
 723         return 0;
 724 }
 725
 726 /* hub-only!! ... and only exported for reset/reinit path.
 727  * otherwise used internally on disconnect/destroy path
 728  */
 729 void usb_destroy_configuration(struct usb_device *dev)
 730 {
 731         int c, i;
 732
 733         if (!dev->config)
 734                 return;
 735
 736         if (dev->rawdescriptors) {
 737                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 738                         kfree(dev->rawdescriptors[i]);
 739
 740                 kfree(dev->rawdescriptors);
 741                 dev->rawdescriptors = NULL;
 742         }
 743
 744         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 745                 struct usb_host_config *cf = &dev->config[c];
 746
 747                 kfree(cf->string);
 748                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 749                         if (cf->intf_cache[i])
 750                                 kref_put(&cf->intf_cache[i]->ref,
 751                                           usb_release_interface_cache);
 752                 }
 753         }
 754         kfree(dev->config);
 755         dev->config = NULL;
 756 }
 757
 758
 759 /*
 760  * Get the USB config descriptors, cache and parse'em
 761  *
 762  * hub-only!! ... and only in reset path, or usb_new_device()
 763  * (used by real hubs and virtual root hubs)
 764  */
 765 int usb_get_configuration(struct usb_device *dev)
 766 {
 767         struct device *ddev = &dev->dev;
 768         int ncfg = dev->descriptor.bNumConfigurations;
 769         int result = 0;
 770         unsigned int cfgno, length;
 771         unsigned char *bigbuffer;
 772         struct usb_config_descriptor *desc;
 773
 774         cfgno = 0;
 775         result = -ENOMEM;
 776         if (ncfg > USB_MAXCONFIG) {
 777                 dev_warn(ddev, "too many configurations: %d, "
 778                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 779                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 780         }
 781
 782         if (ncfg < 1) {
 783                 dev_err(ddev, "no configurations\n");
 784                 return -EINVAL;
 785         }
 786
 787         length = ncfg * sizeof(struct usb_host_config);
 788         dev->config = kzalloc(length, GFP_KERNEL);
 789         if (!dev->config)
 790                 goto err2;
 791
 792         length = ncfg * sizeof(char *);
 793         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 794         if (!dev->rawdescriptors)
 795                 goto err2;
 796
 797         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 798         if (!desc)
 799                 goto err2;
 800
 801         result = 0;
 802         for (; cfgno < ncfg; cfgno++) {
 803                 /* We grab just the first descriptor so we know how long
 804                  * the whole configuration is */
 805                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 806                     desc, USB_DT_CONFIG_SIZE);
 807                 if (result < 0) {
 808                         dev_err(ddev, "unable to read config index %d "
 809                             "descriptor/%s: %d\n", cfgno, "start", result);
 810                         if (result != -EPIPE)
 811                                 goto err;
 812                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 813                         dev->descriptor.bNumConfigurations = cfgno;
 814                         break;
 815                 } else if (result < 4) {
 816                         dev_err(ddev, "config index %d descriptor too short "
 817                             "(expected %i, got %i)\n", cfgno,
 818                             USB_DT_CONFIG_SIZE, result);
 819                         result = -EINVAL;
 820                         goto err;
 821                 }
 822                 length = max((int) le16_to_cpu(desc->wTotalLength),
 823                     USB_DT_CONFIG_SIZE);
 824
 825                 /* Now that we know the length, get the whole thing */
 826                 bigbuffer = kmalloc(length, GFP_KERNEL);
 827                 if (!bigbuffer) {
 828                         result = -ENOMEM;
 829                         goto err;
 830                 }
 831
 832                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 833                         msleep(200);
 834
 835                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 836                     bigbuffer, length);
 837                 if (result < 0) {
 838                         dev_err(ddev, "unable to read config index %d "
 839                             "descriptor/%s\n", cfgno, "all");
 840                         kfree(bigbuffer);
 841                         goto err;
 842                 }
 843                 if (result < length) {
 844                         dev_warn(ddev, "config index %d descriptor too short "
 845                             "(expected %i, got %i)\n", cfgno, length, result);
 846                         length = result;
 847                 }
 848
 849                 dev->rawdescriptors[cfgno] = bigbuffer;
 850
 851                 result = usb_parse_configuration(dev, cfgno,
 852                     &dev->config[cfgno], bigbuffer, length);
 853                 if (result < 0) {
 854                         ++cfgno;
 855                         goto err;
 856                 }
 857         }
 858         result = 0;
 859
 860 err:
 861         kfree(desc);
 862         dev->descriptor.bNumConfigurations = cfgno;
 863 err2:
 864         if (result == -ENOMEM)
 865                 dev_err(ddev, "out of memory\n");
 866         return result;
 867 }
 868
 869 void usb_release_bos_descriptor(struct usb_device *dev)
 870 {
 871         if (dev->bos) {
 872                 kfree(dev->bos->desc);
 873                 kfree(dev->bos);
 874                 dev->bos = NULL;
 875         }
 876 }
 877
 878 static const __u8 bos_desc_len[256] = {
 879         [USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
 880         [USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
 881         [USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
 882         [USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
 883         [CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
 884         [USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
 885 };
 886
 887 /* Get BOS descriptor set */
 888 int usb_get_bos_descriptor(struct usb_device *dev)
 889 {
 890         struct device *ddev = &dev->dev;
 891         struct usb_bos_descriptor *bos;
 892         struct usb_dev_cap_header *cap;
 893         struct usb_ssp_cap_descriptor *ssp_cap;
 894         unsigned char *buffer;
 895         int length, total_len, num, i, ssac;
 896         __u8 cap_type;
 897         int ret;
 898
 899         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 900         if (!bos)
 901                 return -ENOMEM;
 902
 903         /* Get BOS descriptor */
 904         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 905         if (ret < USB_DT_BOS_SIZE) {
 906                 dev_err(ddev, "unable to get BOS descriptor\n");
 907                 if (ret >= 0)
 908                         ret = -ENOMSG;
 909                 kfree(bos);
 910                 return ret;
 911         }
 912
 913         length = bos->bLength;
 914         total_len = le16_to_cpu(bos->wTotalLength);
 915         num = bos->bNumDeviceCaps;
 916         kfree(bos);
 917         if (total_len < length)
 918                 return -EINVAL;
 919
 920         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 921         if (!dev->bos)
 922                 return -ENOMEM;
 923
 924         /* Now let's get the whole BOS descriptor set */
 925         buffer = kzalloc(total_len, GFP_KERNEL);
 926         if (!buffer) {
 927                 ret = -ENOMEM;
 928                 goto err;
 929         }
 930         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 931
 932         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 933         if (ret < total_len) {
 934                 dev_err(ddev, "unable to get BOS descriptor set\n");
 935                 if (ret >= 0)
 936                         ret = -ENOMSG;
 937                 goto err;
 938         }
 939         total_len -= length;
 940
 941         for (i = 0; i < num; i++) {
 942                 buffer += length;
 943                 cap = (struct usb_dev_cap_header *)buffer;
 944
 945                 if (total_len < sizeof(*cap) || total_len < cap->bLength) {
 946                         dev->bos->desc->bNumDeviceCaps = i;
 947                         break;
 948                 }
 949                 cap_type = cap->bDevCapabilityType;
 950                 length = cap->bLength;
 951                 if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
 952                         dev->bos->desc->bNumDeviceCaps = i;
 953                         break;
 954                 }
 955
 956                 total_len -= length;
 957
 958                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 959                         dev_warn(ddev, "descriptor type invalid, skip\n");
 960                         continue;
 961                 }
 962
 963                 switch (cap_type) {
 964                 case USB_CAP_TYPE_WIRELESS_USB:
 965                         /* Wireless USB cap descriptor is handled by wusb */
 966                         break;
 967                 case USB_CAP_TYPE_EXT:
 968                         dev->bos->ext_cap =
 969                                 (struct usb_ext_cap_descriptor *)buffer;
 970                         break;
 971                 case USB_SS_CAP_TYPE:
 972                         dev->bos->ss_cap =
 973                                 (struct usb_ss_cap_descriptor *)buffer;
 974                         break;
 975                 case USB_SSP_CAP_TYPE:
 976                         ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
 977                         ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
 978                                 USB_SSP_SUBLINK_SPEED_ATTRIBS);
 979                         if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
 980                                 dev->bos->ssp_cap = ssp_cap;
 981                         break;
 982                 case CONTAINER_ID_TYPE:
 983                         dev->bos->ss_id =
 984                                 (struct usb_ss_container_id_descriptor *)buffer;
 985                         break;
 986                 case USB_PTM_CAP_TYPE:
 987                         dev->bos->ptm_cap =
 988                                 (struct usb_ptm_cap_descriptor *)buffer;
 989                 default:
 990                         break;
 991                 }
 992         }
 993
 994         return 0;
 995
 996 err:
 997         usb_release_bos_descriptor(dev);
 998         return ret;
 999 }