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         /* Check for duplicate endpoint addresses */
 238         for (i = 0; i < ifp->desc.bNumEndpoints; ++i) {
 239                 if (ifp->endpoint[i].desc.bEndpointAddress ==
 240                     d->bEndpointAddress) {
 241                         dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
 242                             cfgno, inum, asnum, d->bEndpointAddress);
 243                         goto skip_to_next_endpoint_or_interface_descriptor;
 244                 }
 245         }
 246
 247         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 248         ++ifp->desc.bNumEndpoints;
 249
 250         memcpy(&endpoint->desc, d, n);
 251         INIT_LIST_HEAD(&endpoint->urb_list);
 252
 253         /*
 254          * Fix up bInterval values outside the legal range.
 255          * Use 10 or 8 ms if no proper value can be guessed.
 256          */
 257         i = 0;          /* i = min, j = max, n = default */
 258         j = 255;
 259         if (usb_endpoint_xfer_int(d)) {
 260                 i = 1;
 261                 switch (to_usb_device(ddev)->speed) {
 262                 case USB_SPEED_SUPER_PLUS:
 263                 case USB_SPEED_SUPER:
 264                 case USB_SPEED_HIGH:
 265                         /*
 266                          * Many device manufacturers are using full-speed
 267                          * bInterval values in high-speed interrupt endpoint
 268                          * descriptors. Try to fix those and fall back to an
 269                          * 8-ms default value otherwise.
 270                          */
 271                         n = fls(d->bInterval*8);
 272                         if (n == 0)
 273                                 n = 7;  /* 8 ms = 2^(7-1) uframes */
 274                         j = 16;
 275
 276                         /*
 277                          * Adjust bInterval for quirked devices.
 278                          */
 279                         /*
 280                          * This quirk fixes bIntervals reported in ms.
 281                          */
 282                         if (to_usb_device(ddev)->quirks &
 283                                 USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 284                                 n = clamp(fls(d->bInterval) + 3, i, j);
 285                                 i = j = n;
 286                         }
 287                         /*
 288                          * This quirk fixes bIntervals reported in
 289                          * linear microframes.
 290                          */
 291                         if (to_usb_device(ddev)->quirks &
 292                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 293                                 n = clamp(fls(d->bInterval), i, j);
 294                                 i = j = n;
 295                         }
 296                         break;
 297                 default:                /* USB_SPEED_FULL or _LOW */
 298                         /*
 299                          * For low-speed, 10 ms is the official minimum.
 300                          * But some "overclocked" devices might want faster
 301                          * polling so we'll allow it.
 302                          */
 303                         n = 10;
 304                         break;
 305                 }
 306         } else if (usb_endpoint_xfer_isoc(d)) {
 307                 i = 1;
 308                 j = 16;
 309                 switch (to_usb_device(ddev)->speed) {
 310                 case USB_SPEED_HIGH:
 311                         n = 7;          /* 8 ms = 2^(7-1) uframes */
 312                         break;
 313                 default:                /* USB_SPEED_FULL */
 314                         n = 4;          /* 8 ms = 2^(4-1) frames */
 315                         break;
 316                 }
 317         }
 318         if (d->bInterval < i || d->bInterval > j) {
 319                 dev_warn(ddev, "config %d interface %d altsetting %d "
 320                     "endpoint 0x%X has an invalid bInterval %d, "
 321                     "changing to %d\n",
 322                     cfgno, inum, asnum,
 323                     d->bEndpointAddress, d->bInterval, n);
 324                 endpoint->desc.bInterval = n;
 325         }
 326
 327         /* Some buggy low-speed devices have Bulk endpoints, which is
 328          * explicitly forbidden by the USB spec.  In an attempt to make
 329          * them usable, we will try treating them as Interrupt endpoints.
 330          */
 331         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 332                         usb_endpoint_xfer_bulk(d)) {
 333                 dev_warn(ddev, "config %d interface %d altsetting %d "
 334                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 335                     cfgno, inum, asnum, d->bEndpointAddress);
 336                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 337                 endpoint->desc.bInterval = 1;
 338                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 339                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 340         }
 341
 342         /* Validate the wMaxPacketSize field */
 343         maxp = usb_endpoint_maxp(&endpoint->desc);
 344
 345         /* Find the highest legal maxpacket size for this endpoint */
 346         i = 0;          /* additional transactions per microframe */
 347         switch (to_usb_device(ddev)->speed) {
 348         case USB_SPEED_LOW:
 349                 maxpacket_maxes = low_speed_maxpacket_maxes;
 350                 break;
 351         case USB_SPEED_FULL:
 352                 maxpacket_maxes = full_speed_maxpacket_maxes;
 353                 break;
 354         case USB_SPEED_HIGH:
 355                 /* Bits 12..11 are allowed only for HS periodic endpoints */
 356                 if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 357                         i = maxp & (BIT(12) | BIT(11));
 358                         maxp &= ~i;
 359                 }
 360                 /* fallthrough */
 361         default:
 362                 maxpacket_maxes = high_speed_maxpacket_maxes;
 363                 break;
 364         case USB_SPEED_SUPER:
 365         case USB_SPEED_SUPER_PLUS:
 366                 maxpacket_maxes = super_speed_maxpacket_maxes;
 367                 break;
 368         }
 369         j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 370
 371         if (maxp > j) {
 372                 dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 373                     cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 374                 maxp = j;
 375                 endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 376         }
 377
 378         /*
 379          * Some buggy high speed devices have bulk endpoints using
 380          * maxpacket sizes other than 512.  High speed HCDs may not
 381          * be able to handle that particular bug, so let's warn...
 382          */
 383         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 384                         && usb_endpoint_xfer_bulk(d)) {
 385                 if (maxp != 512)
 386                         dev_warn(ddev, "config %d interface %d altsetting %d "
 387                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 388                                 cfgno, inum, asnum, d->bEndpointAddress,
 389                                 maxp);
 390         }
 391
 392         /* Parse a possible SuperSpeed endpoint companion descriptor */
 393         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 394                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 395                                 inum, asnum, endpoint, buffer, size);
 396
 397         /* Skip over any Class Specific or Vendor Specific descriptors;
 398          * find the next endpoint or interface descriptor */
 399         endpoint->extra = buffer;
 400         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 401                         USB_DT_INTERFACE, &n);
 402         endpoint->extralen = i;
 403         retval = buffer - buffer0 + i;
 404         if (n > 0)
 405                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 406                     n, plural(n), "endpoint");
 407         return retval;
 408
 409 skip_to_next_endpoint_or_interface_descriptor:
 410         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 411             USB_DT_INTERFACE, NULL);
 412         return buffer - buffer0 + i;
 413 }
 414
 415 void usb_release_interface_cache(struct kref *ref)
 416 {
 417         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 418         int j;
 419
 420         for (j = 0; j < intfc->num_altsetting; j++) {
 421                 struct usb_host_interface *alt = &intfc->altsetting[j];
 422
 423                 kfree(alt->endpoint);
 424                 kfree(alt->string);
 425         }
 426         kfree(intfc);
 427 }
 428
 429 static int usb_parse_interface(struct device *ddev, int cfgno,
 430     struct usb_host_config *config, unsigned char *buffer, int size,
 431     u8 inums[], u8 nalts[])
 432 {
 433         unsigned char *buffer0 = buffer;
 434         struct usb_interface_descriptor *d;
 435         int inum, asnum;
 436         struct usb_interface_cache *intfc;
 437         struct usb_host_interface *alt;
 438         int i, n;
 439         int len, retval;
 440         int num_ep, num_ep_orig;
 441
 442         d = (struct usb_interface_descriptor *) buffer;
 443         buffer += d->bLength;
 444         size -= d->bLength;
 445
 446         if (d->bLength < USB_DT_INTERFACE_SIZE)
 447                 goto skip_to_next_interface_descriptor;
 448
 449         /* Which interface entry is this? */
 450         intfc = NULL;
 451         inum = d->bInterfaceNumber;
 452         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 453                 if (inums[i] == inum) {
 454                         intfc = config->intf_cache[i];
 455                         break;
 456                 }
 457         }
 458         if (!intfc || intfc->num_altsetting >= nalts[i])
 459                 goto skip_to_next_interface_descriptor;
 460
 461         /* Check for duplicate altsetting entries */
 462         asnum = d->bAlternateSetting;
 463         for ((i = 0, alt = &intfc->altsetting[0]);
 464               i < intfc->num_altsetting;
 465              (++i, ++alt)) {
 466                 if (alt->desc.bAlternateSetting == asnum) {
 467                         dev_warn(ddev, "Duplicate descriptor for config %d "
 468                             "interface %d altsetting %d, skipping\n",
 469                             cfgno, inum, asnum);
 470                         goto skip_to_next_interface_descriptor;
 471                 }
 472         }
 473
 474         ++intfc->num_altsetting;
 475         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 476
 477         /* Skip over any Class Specific or Vendor Specific descriptors;
 478          * find the first endpoint or interface descriptor */
 479         alt->extra = buffer;
 480         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 481             USB_DT_INTERFACE, &n);
 482         alt->extralen = i;
 483         if (n > 0)
 484                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 485                     n, plural(n), "interface");
 486         buffer += i;
 487         size -= i;
 488
 489         /* Allocate space for the right(?) number of endpoints */
 490         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 491         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 492         if (num_ep > USB_MAXENDPOINTS) {
 493                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 494                     "altsetting %d: %d, using maximum allowed: %d\n",
 495                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 496                 num_ep = USB_MAXENDPOINTS;
 497         }
 498
 499         if (num_ep > 0) {
 500                 /* Can't allocate 0 bytes */
 501                 len = sizeof(struct usb_host_endpoint) * num_ep;
 502                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 503                 if (!alt->endpoint)
 504                         return -ENOMEM;
 505         }
 506
 507         /* Parse all the endpoint descriptors */
 508         n = 0;
 509         while (size > 0) {
 510                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 511                      == USB_DT_INTERFACE)
 512                         break;
 513                 retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
 514                     num_ep, buffer, size);
 515                 if (retval < 0)
 516                         return retval;
 517                 ++n;
 518
 519                 buffer += retval;
 520                 size -= retval;
 521         }
 522
 523         if (n != num_ep_orig)
 524                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 525                     "endpoint descriptor%s, different from the interface "
 526                     "descriptor's value: %d\n",
 527                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 528         return buffer - buffer0;
 529
 530 skip_to_next_interface_descriptor:
 531         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 532             USB_DT_INTERFACE, NULL);
 533         return buffer - buffer0 + i;
 534 }
 535
 536 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 537     struct usb_host_config *config, unsigned char *buffer, int size)
 538 {
 539         struct device *ddev = &dev->dev;
 540         unsigned char *buffer0 = buffer;
 541         int cfgno;
 542         int nintf, nintf_orig;
 543         int i, j, n;
 544         struct usb_interface_cache *intfc;
 545         unsigned char *buffer2;
 546         int size2;
 547         struct usb_descriptor_header *header;
 548         int len, retval;
 549         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 550         unsigned iad_num = 0;
 551
 552         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 553         nintf = nintf_orig = config->desc.bNumInterfaces;
 554         config->desc.bNumInterfaces = 0;        // Adjusted later
 555
 556         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 557             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 558             config->desc.bLength > size) {
 559                 dev_err(ddev, "invalid descriptor for config index %d: "
 560                     "type = 0x%X, length = %d\n", cfgidx,
 561                     config->desc.bDescriptorType, config->desc.bLength);
 562                 return -EINVAL;
 563         }
 564         cfgno = config->desc.bConfigurationValue;
 565
 566         buffer += config->desc.bLength;
 567         size -= config->desc.bLength;
 568
 569         if (nintf > USB_MAXINTERFACES) {
 570                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 571                     "using maximum allowed: %d\n",
 572                     cfgno, nintf, USB_MAXINTERFACES);
 573                 nintf = USB_MAXINTERFACES;
 574         }
 575
 576         /* Go through the descriptors, checking their length and counting the
 577          * number of altsettings for each interface */
 578         n = 0;
 579         for ((buffer2 = buffer, size2 = size);
 580               size2 > 0;
 581              (buffer2 += header->bLength, size2 -= header->bLength)) {
 582
 583                 if (size2 < sizeof(struct usb_descriptor_header)) {
 584                         dev_warn(ddev, "config %d descriptor has %d excess "
 585                             "byte%s, ignoring\n",
 586                             cfgno, size2, plural(size2));
 587                         break;
 588                 }
 589
 590                 header = (struct usb_descriptor_header *) buffer2;
 591                 if ((header->bLength > size2) || (header->bLength < 2)) {
 592                         dev_warn(ddev, "config %d has an invalid descriptor "
 593                             "of length %d, skipping remainder of the config\n",
 594                             cfgno, header->bLength);
 595                         break;
 596                 }
 597
 598                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 599                         struct usb_interface_descriptor *d;
 600                         int inum;
 601
 602                         d = (struct usb_interface_descriptor *) header;
 603                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 604                                 dev_warn(ddev, "config %d has an invalid "
 605                                     "interface descriptor of length %d, "
 606                                     "skipping\n", cfgno, d->bLength);
 607                                 continue;
 608                         }
 609
 610                         inum = d->bInterfaceNumber;
 611
 612                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 613                             n >= nintf_orig) {
 614                                 dev_warn(ddev, "config %d has more interface "
 615                                     "descriptors, than it declares in "
 616                                     "bNumInterfaces, ignoring interface "
 617                                     "number: %d\n", cfgno, inum);
 618                                 continue;
 619                         }
 620
 621                         if (inum >= nintf_orig)
 622                                 dev_warn(ddev, "config %d has an invalid "
 623                                     "interface number: %d but max is %d\n",
 624                                     cfgno, inum, nintf_orig - 1);
 625
 626                         /* Have we already encountered this interface?
 627                          * Count its altsettings */
 628                         for (i = 0; i < n; ++i) {
 629                                 if (inums[i] == inum)
 630                                         break;
 631                         }
 632                         if (i < n) {
 633                                 if (nalts[i] < 255)
 634                                         ++nalts[i];
 635                         } else if (n < USB_MAXINTERFACES) {
 636                                 inums[n] = inum;
 637                                 nalts[n] = 1;
 638                                 ++n;
 639                         }
 640
 641                 } else if (header->bDescriptorType ==
 642                                 USB_DT_INTERFACE_ASSOCIATION) {
 643                         struct usb_interface_assoc_descriptor *d;
 644
 645                         d = (struct usb_interface_assoc_descriptor *)header;
 646                         if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
 647                                 dev_warn(ddev,
 648                                          "config %d has an invalid interface association descriptor of length %d, skipping\n",
 649                                          cfgno, d->bLength);
 650                                 continue;
 651                         }
 652
 653                         if (iad_num == USB_MAXIADS) {
 654                                 dev_warn(ddev, "found more Interface "
 655                                                "Association Descriptors "
 656                                                "than allocated for in "
 657                                                "configuration %d\n", cfgno);
 658                         } else {
 659                                 config->intf_assoc[iad_num] = d;
 660                                 iad_num++;
 661                         }
 662
 663                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 664                             header->bDescriptorType == USB_DT_CONFIG)
 665                         dev_warn(ddev, "config %d contains an unexpected "
 666                             "descriptor of type 0x%X, skipping\n",
 667                             cfgno, header->bDescriptorType);
 668
 669         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 670         size = buffer2 - buffer;
 671         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 672
 673         if (n != nintf)
 674                 dev_warn(ddev, "config %d has %d interface%s, different from "
 675                     "the descriptor's value: %d\n",
 676                     cfgno, n, plural(n), nintf_orig);
 677         else if (n == 0)
 678                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 679         config->desc.bNumInterfaces = nintf = n;
 680
 681         /* Check for missing interface numbers */
 682         for (i = 0; i < nintf; ++i) {
 683                 for (j = 0; j < nintf; ++j) {
 684                         if (inums[j] == i)
 685                                 break;
 686                 }
 687                 if (j >= nintf)
 688                         dev_warn(ddev, "config %d has no interface number "
 689                             "%d\n", cfgno, i);
 690         }
 691
 692         /* Allocate the usb_interface_caches and altsetting arrays */
 693         for (i = 0; i < nintf; ++i) {
 694                 j = nalts[i];
 695                 if (j > USB_MAXALTSETTING) {
 696                         dev_warn(ddev, "too many alternate settings for "
 697                             "config %d interface %d: %d, "
 698                             "using maximum allowed: %d\n",
 699                             cfgno, inums[i], j, USB_MAXALTSETTING);
 700                         nalts[i] = j = USB_MAXALTSETTING;
 701                 }
 702
 703                 len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
 704                 config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
 705                 if (!intfc)
 706                         return -ENOMEM;
 707                 kref_init(&intfc->ref);
 708         }
 709
 710         /* FIXME: parse the BOS descriptor */
 711
 712         /* Skip over any Class Specific or Vendor Specific descriptors;
 713          * find the first interface descriptor */
 714         config->extra = buffer;
 715         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 716             USB_DT_INTERFACE, &n);
 717         config->extralen = i;
 718         if (n > 0)
 719                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 720                     n, plural(n), "configuration");
 721         buffer += i;
 722         size -= i;
 723
 724         /* Parse all the interface/altsetting descriptors */
 725         while (size > 0) {
 726                 retval = usb_parse_interface(ddev, cfgno, config,
 727                     buffer, size, inums, nalts);
 728                 if (retval < 0)
 729                         return retval;
 730
 731                 buffer += retval;
 732                 size -= retval;
 733         }
 734
 735         /* Check for missing altsettings */
 736         for (i = 0; i < nintf; ++i) {
 737                 intfc = config->intf_cache[i];
 738                 for (j = 0; j < intfc->num_altsetting; ++j) {
 739                         for (n = 0; n < intfc->num_altsetting; ++n) {
 740                                 if (intfc->altsetting[n].desc.
 741                                     bAlternateSetting == j)
 742                                         break;
 743                         }
 744                         if (n >= intfc->num_altsetting)
 745                                 dev_warn(ddev, "config %d interface %d has no "
 746                                     "altsetting %d\n", cfgno, inums[i], j);
 747                 }
 748         }
 749
 750         return 0;
 751 }
 752
 753 /* hub-only!! ... and only exported for reset/reinit path.
 754  * otherwise used internally on disconnect/destroy path
 755  */
 756 void usb_destroy_configuration(struct usb_device *dev)
 757 {
 758         int c, i;
 759
 760         if (!dev->config)
 761                 return;
 762
 763         if (dev->rawdescriptors) {
 764                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 765                         kfree(dev->rawdescriptors[i]);
 766
 767                 kfree(dev->rawdescriptors);
 768                 dev->rawdescriptors = NULL;
 769         }
 770
 771         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 772                 struct usb_host_config *cf = &dev->config[c];
 773
 774                 kfree(cf->string);
 775                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 776                         if (cf->intf_cache[i])
 777                                 kref_put(&cf->intf_cache[i]->ref,
 778                                           usb_release_interface_cache);
 779                 }
 780         }
 781         kfree(dev->config);
 782         dev->config = NULL;
 783 }
 784
 785
 786 /*
 787  * Get the USB config descriptors, cache and parse'em
 788  *
 789  * hub-only!! ... and only in reset path, or usb_new_device()
 790  * (used by real hubs and virtual root hubs)
 791  */
 792 int usb_get_configuration(struct usb_device *dev)
 793 {
 794         struct device *ddev = &dev->dev;
 795         int ncfg = dev->descriptor.bNumConfigurations;
 796         int result = 0;
 797         unsigned int cfgno, length;
 798         unsigned char *bigbuffer;
 799         struct usb_config_descriptor *desc;
 800
 801         cfgno = 0;
 802         result = -ENOMEM;
 803         if (ncfg > USB_MAXCONFIG) {
 804                 dev_warn(ddev, "too many configurations: %d, "
 805                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 806                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 807         }
 808
 809         if (ncfg < 1) {
 810                 dev_err(ddev, "no configurations\n");
 811                 return -EINVAL;
 812         }
 813
 814         length = ncfg * sizeof(struct usb_host_config);
 815         dev->config = kzalloc(length, GFP_KERNEL);
 816         if (!dev->config)
 817                 goto err2;
 818
 819         length = ncfg * sizeof(char *);
 820         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 821         if (!dev->rawdescriptors)
 822                 goto err2;
 823
 824         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 825         if (!desc)
 826                 goto err2;
 827
 828         result = 0;
 829         for (; cfgno < ncfg; cfgno++) {
 830                 /* We grab just the first descriptor so we know how long
 831                  * the whole configuration is */
 832                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 833                     desc, USB_DT_CONFIG_SIZE);
 834                 if (result < 0) {
 835                         dev_err(ddev, "unable to read config index %d "
 836                             "descriptor/%s: %d\n", cfgno, "start", result);
 837                         if (result != -EPIPE)
 838                                 goto err;
 839                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 840                         dev->descriptor.bNumConfigurations = cfgno;
 841                         break;
 842                 } else if (result < 4) {
 843                         dev_err(ddev, "config index %d descriptor too short "
 844                             "(expected %i, got %i)\n", cfgno,
 845                             USB_DT_CONFIG_SIZE, result);
 846                         result = -EINVAL;
 847                         goto err;
 848                 }
 849                 length = max((int) le16_to_cpu(desc->wTotalLength),
 850                     USB_DT_CONFIG_SIZE);
 851
 852                 /* Now that we know the length, get the whole thing */
 853                 bigbuffer = kmalloc(length, GFP_KERNEL);
 854                 if (!bigbuffer) {
 855                         result = -ENOMEM;
 856                         goto err;
 857                 }
 858
 859                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 860                         msleep(200);
 861
 862                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 863                     bigbuffer, length);
 864                 if (result < 0) {
 865                         dev_err(ddev, "unable to read config index %d "
 866                             "descriptor/%s\n", cfgno, "all");
 867                         kfree(bigbuffer);
 868                         goto err;
 869                 }
 870                 if (result < length) {
 871                         dev_warn(ddev, "config index %d descriptor too short "
 872                             "(expected %i, got %i)\n", cfgno, length, result);
 873                         length = result;
 874                 }
 875
 876                 dev->rawdescriptors[cfgno] = bigbuffer;
 877
 878                 result = usb_parse_configuration(dev, cfgno,
 879                     &dev->config[cfgno], bigbuffer, length);
 880                 if (result < 0) {
 881                         ++cfgno;
 882                         goto err;
 883                 }
 884         }
 885         result = 0;
 886
 887 err:
 888         kfree(desc);
 889         dev->descriptor.bNumConfigurations = cfgno;
 890 err2:
 891         if (result == -ENOMEM)
 892                 dev_err(ddev, "out of memory\n");
 893         return result;
 894 }
 895
 896 void usb_release_bos_descriptor(struct usb_device *dev)
 897 {
 898         if (dev->bos) {
 899                 kfree(dev->bos->desc);
 900                 kfree(dev->bos);
 901                 dev->bos = NULL;
 902         }
 903 }
 904
 905 static const __u8 bos_desc_len[256] = {
 906         [USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
 907         [USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
 908         [USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
 909         [USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
 910         [CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
 911         [USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
 912 };
 913
 914 /* Get BOS descriptor set */
 915 int usb_get_bos_descriptor(struct usb_device *dev)
 916 {
 917         struct device *ddev = &dev->dev;
 918         struct usb_bos_descriptor *bos;
 919         struct usb_dev_cap_header *cap;
 920         struct usb_ssp_cap_descriptor *ssp_cap;
 921         unsigned char *buffer;
 922         int length, total_len, num, i, ssac;
 923         __u8 cap_type;
 924         int ret;
 925
 926         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 927         if (!bos)
 928                 return -ENOMEM;
 929
 930         /* Get BOS descriptor */
 931         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 932         if (ret < USB_DT_BOS_SIZE) {
 933                 dev_err(ddev, "unable to get BOS descriptor\n");
 934                 if (ret >= 0)
 935                         ret = -ENOMSG;
 936                 kfree(bos);
 937                 return ret;
 938         }
 939
 940         length = bos->bLength;
 941         total_len = le16_to_cpu(bos->wTotalLength);
 942         num = bos->bNumDeviceCaps;
 943         kfree(bos);
 944         if (total_len < length)
 945                 return -EINVAL;
 946
 947         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
 948         if (!dev->bos)
 949                 return -ENOMEM;
 950
 951         /* Now let's get the whole BOS descriptor set */
 952         buffer = kzalloc(total_len, GFP_KERNEL);
 953         if (!buffer) {
 954                 ret = -ENOMEM;
 955                 goto err;
 956         }
 957         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
 958
 959         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
 960         if (ret < total_len) {
 961                 dev_err(ddev, "unable to get BOS descriptor set\n");
 962                 if (ret >= 0)
 963                         ret = -ENOMSG;
 964                 goto err;
 965         }
 966         total_len -= length;
 967
 968         for (i = 0; i < num; i++) {
 969                 buffer += length;
 970                 cap = (struct usb_dev_cap_header *)buffer;
 971
 972                 if (total_len < sizeof(*cap) || total_len < cap->bLength) {
 973                         dev->bos->desc->bNumDeviceCaps = i;
 974                         break;
 975                 }
 976                 cap_type = cap->bDevCapabilityType;
 977                 length = cap->bLength;
 978                 if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
 979                         dev->bos->desc->bNumDeviceCaps = i;
 980                         break;
 981                 }
 982
 983                 total_len -= length;
 984
 985                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
 986                         dev_warn(ddev, "descriptor type invalid, skip\n");
 987                         continue;
 988                 }
 989
 990                 switch (cap_type) {
 991                 case USB_CAP_TYPE_WIRELESS_USB:
 992                         /* Wireless USB cap descriptor is handled by wusb */
 993                         break;
 994                 case USB_CAP_TYPE_EXT:
 995                         dev->bos->ext_cap =
 996                                 (struct usb_ext_cap_descriptor *)buffer;
 997                         break;
 998                 case USB_SS_CAP_TYPE:
 999                         dev->bos->ss_cap =
1000                                 (struct usb_ss_cap_descriptor *)buffer;
1001                         break;
1002                 case USB_SSP_CAP_TYPE:
1003                         ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
1004                         ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
1005                                 USB_SSP_SUBLINK_SPEED_ATTRIBS);
1006                         if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
1007                                 dev->bos->ssp_cap = ssp_cap;
1008                         break;
1009                 case CONTAINER_ID_TYPE:
1010                         dev->bos->ss_id =
1011                                 (struct usb_ss_container_id_descriptor *)buffer;
1012                         break;
1013                 case USB_PTM_CAP_TYPE:
1014                         dev->bos->ptm_cap =
1015                                 (struct usb_ptm_cap_descriptor *)buffer;
1016                 default:
1017                         break;
1018                 }
1019         }
1020
1021         return 0;
1022
1023 err:
1024         usb_release_bos_descriptor(dev);
1025         return ret;
1026 }