drivers/usb/core/config.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
plural
find_next_descriptor
usb_parse_ssp_isoc_endpoint_companion
usb_parse_ss_endpoint_companion
endpoint_is_duplicate
config_endpoint_is_duplicate
usb_parse_endpoint
usb_release_interface_cache
usb_parse_interface
usb_parse_configuration
usb_destroy_configuration
usb_get_configuration
usb_release_bos_descriptor
usb_get_bos_descriptor
   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Released under the GPLv2 only.
   4  */
   5 
   6 #include <linux/usb.h>
   7 #include <linux/usb/ch9.h>
   8 #include <linux/usb/hcd.h>
   9 #include <linux/usb/quirks.h>
  10 #include <linux/module.h>
  11 #include <linux/slab.h>
  12 #include <linux/device.h>
  13 #include <asm/byteorder.h>
  14 #include "usb.h"
  15 
  16 
  17 #define USB_MAXALTSETTING               128     /* Hard limit */
  18 
  19 #define USB_MAXCONFIG                   8       /* Arbitrary limit */
  20 
  21 
  22 static inline const char *plural(int n)
  23 {
  24         return (n == 1 ? "" : "s");
  25 }
  26 
  27 static int find_next_descriptor(unsigned char *buffer, int size,
  28     int dt1, int dt2, int *num_skipped)
  29 {
  30         struct usb_descriptor_header *h;
  31         int n = 0;
  32         unsigned char *buffer0 = buffer;
  33 
  34         /* Find the next descriptor of type dt1 or dt2 */
  35         while (size > 0) {
  36                 h = (struct usb_descriptor_header *) buffer;
  37                 if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
  38                         break;
  39                 buffer += h->bLength;
  40                 size -= h->bLength;
  41                 ++n;
  42         }
  43 
  44         /* Store the number of descriptors skipped and return the
  45          * number of bytes skipped */
  46         if (num_skipped)
  47                 *num_skipped = n;
  48         return buffer - buffer0;
  49 }
  50 
  51 static void usb_parse_ssp_isoc_endpoint_companion(struct device *ddev,
  52                 int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
  53                 unsigned char *buffer, int size)
  54 {
  55         struct usb_ssp_isoc_ep_comp_descriptor *desc;
  56 
  57         /*
  58          * The SuperSpeedPlus Isoc endpoint companion descriptor immediately
  59          * follows the SuperSpeed Endpoint Companion descriptor
  60          */
  61         desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;
  62         if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||
  63             size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {
  64                 dev_warn(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"
  65                          "for config %d interface %d altsetting %d ep %d.\n",
  66                          cfgno, inum, asnum, ep->desc.bEndpointAddress);
  67                 return;
  68         }
  69         memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);
  70 }
  71 
  72 static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
  73                 int inum, int asnum, struct usb_host_endpoint *ep,
  74                 unsigned char *buffer, int size)
  75 {
  76         struct usb_ss_ep_comp_descriptor *desc;
  77         int max_tx;
  78 
  79         /* The SuperSpeed endpoint companion descriptor is supposed to
  80          * be the first thing immediately following the endpoint descriptor.
  81          */
  82         desc = (struct usb_ss_ep_comp_descriptor *) buffer;
  83 
  84         if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
  85                         size < USB_DT_SS_EP_COMP_SIZE) {
  86                 dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
  87                                 " interface %d altsetting %d ep %d: "
  88                                 "using minimum values\n",
  89                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
  90 
  91                 /* Fill in some default values.
  92                  * Leave bmAttributes as zero, which will mean no streams for
  93                  * bulk, and isoc won't support multiple bursts of packets.
  94                  * With bursts of only one packet, and a Mult of 1, the max
  95                  * amount of data moved per endpoint service interval is one
  96                  * packet.
  97                  */
  98                 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
  99                 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
 100                 if (usb_endpoint_xfer_isoc(&ep->desc) ||
 101                                 usb_endpoint_xfer_int(&ep->desc))
 102                         ep->ss_ep_comp.wBytesPerInterval =
 103                                         ep->desc.wMaxPacketSize;
 104                 return;
 105         }
 106         buffer += desc->bLength;
 107         size -= desc->bLength;
 108         memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 109 
 110         /* Check the various values */
 111         if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 112                 dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
 113                                 "config %d interface %d altsetting %d ep %d: "
 114                                 "setting to zero\n", desc->bMaxBurst,
 115                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 116                 ep->ss_ep_comp.bMaxBurst = 0;
 117         } else if (desc->bMaxBurst > 15) {
 118                 dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
 119                                 "config %d interface %d altsetting %d ep %d: "
 120                                 "setting to 15\n", desc->bMaxBurst,
 121                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 122                 ep->ss_ep_comp.bMaxBurst = 15;
 123         }
 124 
 125         if ((usb_endpoint_xfer_control(&ep->desc) ||
 126                         usb_endpoint_xfer_int(&ep->desc)) &&
 127                                 desc->bmAttributes != 0) {
 128                 dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
 129                                 "config %d interface %d altsetting %d ep %d: "
 130                                 "setting to zero\n",
 131                                 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 132                                 desc->bmAttributes,
 133                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 134                 ep->ss_ep_comp.bmAttributes = 0;
 135         } else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 136                         desc->bmAttributes > 16) {
 137                 dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
 138                                 "config %d interface %d altsetting %d ep %d: "
 139                                 "setting to max\n",
 140                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 141                 ep->ss_ep_comp.bmAttributes = 16;
 142         } else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 143                    !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
 144                    USB_SS_MULT(desc->bmAttributes) > 3) {
 145                 dev_warn(ddev, "Isoc endpoint has Mult of %d in "
 146                                 "config %d interface %d altsetting %d ep %d: "
 147                                 "setting to 3\n",
 148                                 USB_SS_MULT(desc->bmAttributes),
 149                                 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 150                 ep->ss_ep_comp.bmAttributes = 2;
 151         }
 152 
 153         if (usb_endpoint_xfer_isoc(&ep->desc))
 154                 max_tx = (desc->bMaxBurst + 1) *
 155                         (USB_SS_MULT(desc->bmAttributes)) *
 156                         usb_endpoint_maxp(&ep->desc);
 157         else if (usb_endpoint_xfer_int(&ep->desc))
 158                 max_tx = usb_endpoint_maxp(&ep->desc) *
 159                         (desc->bMaxBurst + 1);
 160         else
 161                 max_tx = 999999;
 162         if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 163                 dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
 164                                 "config %d interface %d altsetting %d ep %d: "
 165                                 "setting to %d\n",
 166                                 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 167                                 le16_to_cpu(desc->wBytesPerInterval),
 168                                 cfgno, inum, asnum, ep->desc.bEndpointAddress,
 169                                 max_tx);
 170                 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 171         }
 172         /* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
 173         if (usb_endpoint_xfer_isoc(&ep->desc) &&
 174             USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
 175                 usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 176                                                         ep, buffer, size);
 177 }
 178 
 179 static const unsigned short low_speed_maxpacket_maxes[4] = {
 180         [USB_ENDPOINT_XFER_CONTROL] = 8,
 181         [USB_ENDPOINT_XFER_ISOC] = 0,
 182         [USB_ENDPOINT_XFER_BULK] = 0,
 183         [USB_ENDPOINT_XFER_INT] = 8,
 184 };
 185 static const unsigned short full_speed_maxpacket_maxes[4] = {
 186         [USB_ENDPOINT_XFER_CONTROL] = 64,
 187         [USB_ENDPOINT_XFER_ISOC] = 1023,
 188         [USB_ENDPOINT_XFER_BULK] = 64,
 189         [USB_ENDPOINT_XFER_INT] = 64,
 190 };
 191 static const unsigned short high_speed_maxpacket_maxes[4] = {
 192         [USB_ENDPOINT_XFER_CONTROL] = 64,
 193         [USB_ENDPOINT_XFER_ISOC] = 1024,
 194 
 195         /* Bulk should be 512, but some devices use 1024: we will warn below */
 196         [USB_ENDPOINT_XFER_BULK] = 1024,
 197         [USB_ENDPOINT_XFER_INT] = 1024,
 198 };
 199 static const unsigned short super_speed_maxpacket_maxes[4] = {
 200         [USB_ENDPOINT_XFER_CONTROL] = 512,
 201         [USB_ENDPOINT_XFER_ISOC] = 1024,
 202         [USB_ENDPOINT_XFER_BULK] = 1024,
 203         [USB_ENDPOINT_XFER_INT] = 1024,
 204 };
 205 
 206 static bool endpoint_is_duplicate(struct usb_endpoint_descriptor *e1,
 207                 struct usb_endpoint_descriptor *e2)
 208 {
 209         if (e1->bEndpointAddress == e2->bEndpointAddress)
 210                 return true;
 211 
 212         if (usb_endpoint_xfer_control(e1) || usb_endpoint_xfer_control(e2)) {
 213                 if (usb_endpoint_num(e1) == usb_endpoint_num(e2))
 214                         return true;
 215         }
 216 
 217         return false;
 218 }
 219 
 220 /*
 221  * Check for duplicate endpoint addresses in other interfaces and in the
 222  * altsetting currently being parsed.
 223  */
 224 static bool config_endpoint_is_duplicate(struct usb_host_config *config,
 225                 int inum, int asnum, struct usb_endpoint_descriptor *d)
 226 {
 227         struct usb_endpoint_descriptor *epd;
 228         struct usb_interface_cache *intfc;
 229         struct usb_host_interface *alt;
 230         int i, j, k;
 231 
 232         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 233                 intfc = config->intf_cache[i];
 234 
 235                 for (j = 0; j < intfc->num_altsetting; ++j) {
 236                         alt = &intfc->altsetting[j];
 237 
 238                         if (alt->desc.bInterfaceNumber == inum &&
 239                                         alt->desc.bAlternateSetting != asnum)
 240                                 continue;
 241 
 242                         for (k = 0; k < alt->desc.bNumEndpoints; ++k) {
 243                                 epd = &alt->endpoint[k].desc;
 244 
 245                                 if (endpoint_is_duplicate(epd, d))
 246                                         return true;
 247                         }
 248                 }
 249         }
 250 
 251         return false;
 252 }
 253 
 254 static int usb_parse_endpoint(struct device *ddev, int cfgno,
 255                 struct usb_host_config *config, int inum, int asnum,
 256                 struct usb_host_interface *ifp, int num_ep,
 257                 unsigned char *buffer, int size)
 258 {
 259         struct usb_device *udev = to_usb_device(ddev);
 260         unsigned char *buffer0 = buffer;
 261         struct usb_endpoint_descriptor *d;
 262         struct usb_host_endpoint *endpoint;
 263         int n, i, j, retval;
 264         unsigned int maxp;
 265         const unsigned short *maxpacket_maxes;
 266 
 267         d = (struct usb_endpoint_descriptor *) buffer;
 268         buffer += d->bLength;
 269         size -= d->bLength;
 270 
 271         if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 272                 n = USB_DT_ENDPOINT_AUDIO_SIZE;
 273         else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 274                 n = USB_DT_ENDPOINT_SIZE;
 275         else {
 276                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 277                     "invalid endpoint descriptor of length %d, skipping\n",
 278                     cfgno, inum, asnum, d->bLength);
 279                 goto skip_to_next_endpoint_or_interface_descriptor;
 280         }
 281 
 282         i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
 283         if (i >= 16 || i == 0) {
 284                 dev_warn(ddev, "config %d interface %d altsetting %d has an "
 285                     "invalid endpoint with address 0x%X, skipping\n",
 286                     cfgno, inum, asnum, d->bEndpointAddress);
 287                 goto skip_to_next_endpoint_or_interface_descriptor;
 288         }
 289 
 290         /* Only store as many endpoints as we have room for */
 291         if (ifp->desc.bNumEndpoints >= num_ep)
 292                 goto skip_to_next_endpoint_or_interface_descriptor;
 293 
 294         /* Check for duplicate endpoint addresses */
 295         if (config_endpoint_is_duplicate(config, inum, asnum, d)) {
 296                 dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
 297                                 cfgno, inum, asnum, d->bEndpointAddress);
 298                 goto skip_to_next_endpoint_or_interface_descriptor;
 299         }
 300 
 301         /* Ignore blacklisted endpoints */
 302         if (udev->quirks & USB_QUIRK_ENDPOINT_BLACKLIST) {
 303                 if (usb_endpoint_is_blacklisted(udev, ifp, d)) {
 304                         dev_warn(ddev, "config %d interface %d altsetting %d has a blacklisted endpoint with address 0x%X, skipping\n",
 305                                         cfgno, inum, asnum,
 306                                         d->bEndpointAddress);
 307                         goto skip_to_next_endpoint_or_interface_descriptor;
 308                 }
 309         }
 310 
 311         endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 312         ++ifp->desc.bNumEndpoints;
 313 
 314         memcpy(&endpoint->desc, d, n);
 315         INIT_LIST_HEAD(&endpoint->urb_list);
 316 
 317         /*
 318          * Fix up bInterval values outside the legal range.
 319          * Use 10 or 8 ms if no proper value can be guessed.
 320          */
 321         i = 0;          /* i = min, j = max, n = default */
 322         j = 255;
 323         if (usb_endpoint_xfer_int(d)) {
 324                 i = 1;
 325                 switch (to_usb_device(ddev)->speed) {
 326                 case USB_SPEED_SUPER_PLUS:
 327                 case USB_SPEED_SUPER:
 328                 case USB_SPEED_HIGH:
 329                         /*
 330                          * Many device manufacturers are using full-speed
 331                          * bInterval values in high-speed interrupt endpoint
 332                          * descriptors. Try to fix those and fall back to an
 333                          * 8-ms default value otherwise.
 334                          */
 335                         n = fls(d->bInterval*8);
 336                         if (n == 0)
 337                                 n = 7;  /* 8 ms = 2^(7-1) uframes */
 338                         j = 16;
 339 
 340                         /*
 341                          * Adjust bInterval for quirked devices.
 342                          */
 343                         /*
 344                          * This quirk fixes bIntervals reported in ms.
 345                          */
 346                         if (to_usb_device(ddev)->quirks &
 347                                 USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 348                                 n = clamp(fls(d->bInterval) + 3, i, j);
 349                                 i = j = n;
 350                         }
 351                         /*
 352                          * This quirk fixes bIntervals reported in
 353                          * linear microframes.
 354                          */
 355                         if (to_usb_device(ddev)->quirks &
 356                                 USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 357                                 n = clamp(fls(d->bInterval), i, j);
 358                                 i = j = n;
 359                         }
 360                         break;
 361                 default:                /* USB_SPEED_FULL or _LOW */
 362                         /*
 363                          * For low-speed, 10 ms is the official minimum.
 364                          * But some "overclocked" devices might want faster
 365                          * polling so we'll allow it.
 366                          */
 367                         n = 10;
 368                         break;
 369                 }
 370         } else if (usb_endpoint_xfer_isoc(d)) {
 371                 i = 1;
 372                 j = 16;
 373                 switch (to_usb_device(ddev)->speed) {
 374                 case USB_SPEED_HIGH:
 375                         n = 7;          /* 8 ms = 2^(7-1) uframes */
 376                         break;
 377                 default:                /* USB_SPEED_FULL */
 378                         n = 4;          /* 8 ms = 2^(4-1) frames */
 379                         break;
 380                 }
 381         }
 382         if (d->bInterval < i || d->bInterval > j) {
 383                 dev_warn(ddev, "config %d interface %d altsetting %d "
 384                     "endpoint 0x%X has an invalid bInterval %d, "
 385                     "changing to %d\n",
 386                     cfgno, inum, asnum,
 387                     d->bEndpointAddress, d->bInterval, n);
 388                 endpoint->desc.bInterval = n;
 389         }
 390 
 391         /* Some buggy low-speed devices have Bulk endpoints, which is
 392          * explicitly forbidden by the USB spec.  In an attempt to make
 393          * them usable, we will try treating them as Interrupt endpoints.
 394          */
 395         if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
 396                         usb_endpoint_xfer_bulk(d)) {
 397                 dev_warn(ddev, "config %d interface %d altsetting %d "
 398                     "endpoint 0x%X is Bulk; changing to Interrupt\n",
 399                     cfgno, inum, asnum, d->bEndpointAddress);
 400                 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 401                 endpoint->desc.bInterval = 1;
 402                 if (usb_endpoint_maxp(&endpoint->desc) > 8)
 403                         endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 404         }
 405 
 406         /*
 407          * Validate the wMaxPacketSize field.
 408          * Some devices have isochronous endpoints in altsetting 0;
 409          * the USB-2 spec requires such endpoints to have wMaxPacketSize = 0
 410          * (see the end of section 5.6.3), so don't warn about them.
 411          */
 412         maxp = usb_endpoint_maxp(&endpoint->desc);
 413         if (maxp == 0 && !(usb_endpoint_xfer_isoc(d) && asnum == 0)) {
 414                 dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
 415                     cfgno, inum, asnum, d->bEndpointAddress);
 416         }
 417 
 418         /* Find the highest legal maxpacket size for this endpoint */
 419         i = 0;          /* additional transactions per microframe */
 420         switch (to_usb_device(ddev)->speed) {
 421         case USB_SPEED_LOW:
 422                 maxpacket_maxes = low_speed_maxpacket_maxes;
 423                 break;
 424         case USB_SPEED_FULL:
 425                 maxpacket_maxes = full_speed_maxpacket_maxes;
 426                 break;
 427         case USB_SPEED_HIGH:
 428                 /* Bits 12..11 are allowed only for HS periodic endpoints */
 429                 if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 430                         i = maxp & (BIT(12) | BIT(11));
 431                         maxp &= ~i;
 432                 }
 433                 /* fallthrough */
 434         default:
 435                 maxpacket_maxes = high_speed_maxpacket_maxes;
 436                 break;
 437         case USB_SPEED_SUPER:
 438         case USB_SPEED_SUPER_PLUS:
 439                 maxpacket_maxes = super_speed_maxpacket_maxes;
 440                 break;
 441         }
 442         j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 443 
 444         if (maxp > j) {
 445                 dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 446                     cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 447                 maxp = j;
 448                 endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 449         }
 450 
 451         /*
 452          * Some buggy high speed devices have bulk endpoints using
 453          * maxpacket sizes other than 512.  High speed HCDs may not
 454          * be able to handle that particular bug, so let's warn...
 455          */
 456         if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
 457                         && usb_endpoint_xfer_bulk(d)) {
 458                 if (maxp != 512)
 459                         dev_warn(ddev, "config %d interface %d altsetting %d "
 460                                 "bulk endpoint 0x%X has invalid maxpacket %d\n",
 461                                 cfgno, inum, asnum, d->bEndpointAddress,
 462                                 maxp);
 463         }
 464 
 465         /* Parse a possible SuperSpeed endpoint companion descriptor */
 466         if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
 467                 usb_parse_ss_endpoint_companion(ddev, cfgno,
 468                                 inum, asnum, endpoint, buffer, size);
 469 
 470         /* Skip over any Class Specific or Vendor Specific descriptors;
 471          * find the next endpoint or interface descriptor */
 472         endpoint->extra = buffer;
 473         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 474                         USB_DT_INTERFACE, &n);
 475         endpoint->extralen = i;
 476         retval = buffer - buffer0 + i;
 477         if (n > 0)
 478                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 479                     n, plural(n), "endpoint");
 480         return retval;
 481 
 482 skip_to_next_endpoint_or_interface_descriptor:
 483         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 484             USB_DT_INTERFACE, NULL);
 485         return buffer - buffer0 + i;
 486 }
 487 
 488 void usb_release_interface_cache(struct kref *ref)
 489 {
 490         struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 491         int j;
 492 
 493         for (j = 0; j < intfc->num_altsetting; j++) {
 494                 struct usb_host_interface *alt = &intfc->altsetting[j];
 495 
 496                 kfree(alt->endpoint);
 497                 kfree(alt->string);
 498         }
 499         kfree(intfc);
 500 }
 501 
 502 static int usb_parse_interface(struct device *ddev, int cfgno,
 503     struct usb_host_config *config, unsigned char *buffer, int size,
 504     u8 inums[], u8 nalts[])
 505 {
 506         unsigned char *buffer0 = buffer;
 507         struct usb_interface_descriptor *d;
 508         int inum, asnum;
 509         struct usb_interface_cache *intfc;
 510         struct usb_host_interface *alt;
 511         int i, n;
 512         int len, retval;
 513         int num_ep, num_ep_orig;
 514 
 515         d = (struct usb_interface_descriptor *) buffer;
 516         buffer += d->bLength;
 517         size -= d->bLength;
 518 
 519         if (d->bLength < USB_DT_INTERFACE_SIZE)
 520                 goto skip_to_next_interface_descriptor;
 521 
 522         /* Which interface entry is this? */
 523         intfc = NULL;
 524         inum = d->bInterfaceNumber;
 525         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 526                 if (inums[i] == inum) {
 527                         intfc = config->intf_cache[i];
 528                         break;
 529                 }
 530         }
 531         if (!intfc || intfc->num_altsetting >= nalts[i])
 532                 goto skip_to_next_interface_descriptor;
 533 
 534         /* Check for duplicate altsetting entries */
 535         asnum = d->bAlternateSetting;
 536         for ((i = 0, alt = &intfc->altsetting[0]);
 537               i < intfc->num_altsetting;
 538              (++i, ++alt)) {
 539                 if (alt->desc.bAlternateSetting == asnum) {
 540                         dev_warn(ddev, "Duplicate descriptor for config %d "
 541                             "interface %d altsetting %d, skipping\n",
 542                             cfgno, inum, asnum);
 543                         goto skip_to_next_interface_descriptor;
 544                 }
 545         }
 546 
 547         ++intfc->num_altsetting;
 548         memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 549 
 550         /* Skip over any Class Specific or Vendor Specific descriptors;
 551          * find the first endpoint or interface descriptor */
 552         alt->extra = buffer;
 553         i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 554             USB_DT_INTERFACE, &n);
 555         alt->extralen = i;
 556         if (n > 0)
 557                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 558                     n, plural(n), "interface");
 559         buffer += i;
 560         size -= i;
 561 
 562         /* Allocate space for the right(?) number of endpoints */
 563         num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 564         alt->desc.bNumEndpoints = 0;            /* Use as a counter */
 565         if (num_ep > USB_MAXENDPOINTS) {
 566                 dev_warn(ddev, "too many endpoints for config %d interface %d "
 567                     "altsetting %d: %d, using maximum allowed: %d\n",
 568                     cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 569                 num_ep = USB_MAXENDPOINTS;
 570         }
 571 
 572         if (num_ep > 0) {
 573                 /* Can't allocate 0 bytes */
 574                 len = sizeof(struct usb_host_endpoint) * num_ep;
 575                 alt->endpoint = kzalloc(len, GFP_KERNEL);
 576                 if (!alt->endpoint)
 577                         return -ENOMEM;
 578         }
 579 
 580         /* Parse all the endpoint descriptors */
 581         n = 0;
 582         while (size > 0) {
 583                 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 584                      == USB_DT_INTERFACE)
 585                         break;
 586                 retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
 587                                 alt, num_ep, buffer, size);
 588                 if (retval < 0)
 589                         return retval;
 590                 ++n;
 591 
 592                 buffer += retval;
 593                 size -= retval;
 594         }
 595 
 596         if (n != num_ep_orig)
 597                 dev_warn(ddev, "config %d interface %d altsetting %d has %d "
 598                     "endpoint descriptor%s, different from the interface "
 599                     "descriptor's value: %d\n",
 600                     cfgno, inum, asnum, n, plural(n), num_ep_orig);
 601         return buffer - buffer0;
 602 
 603 skip_to_next_interface_descriptor:
 604         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 605             USB_DT_INTERFACE, NULL);
 606         return buffer - buffer0 + i;
 607 }
 608 
 609 static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 610     struct usb_host_config *config, unsigned char *buffer, int size)
 611 {
 612         struct device *ddev = &dev->dev;
 613         unsigned char *buffer0 = buffer;
 614         int cfgno;
 615         int nintf, nintf_orig;
 616         int i, j, n;
 617         struct usb_interface_cache *intfc;
 618         unsigned char *buffer2;
 619         int size2;
 620         struct usb_descriptor_header *header;
 621         int retval;
 622         u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 623         unsigned iad_num = 0;
 624 
 625         memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 626         nintf = nintf_orig = config->desc.bNumInterfaces;
 627         config->desc.bNumInterfaces = 0;        // Adjusted later
 628 
 629         if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 630             config->desc.bLength < USB_DT_CONFIG_SIZE ||
 631             config->desc.bLength > size) {
 632                 dev_err(ddev, "invalid descriptor for config index %d: "
 633                     "type = 0x%X, length = %d\n", cfgidx,
 634                     config->desc.bDescriptorType, config->desc.bLength);
 635                 return -EINVAL;
 636         }
 637         cfgno = config->desc.bConfigurationValue;
 638 
 639         buffer += config->desc.bLength;
 640         size -= config->desc.bLength;
 641 
 642         if (nintf > USB_MAXINTERFACES) {
 643                 dev_warn(ddev, "config %d has too many interfaces: %d, "
 644                     "using maximum allowed: %d\n",
 645                     cfgno, nintf, USB_MAXINTERFACES);
 646                 nintf = USB_MAXINTERFACES;
 647         }
 648 
 649         /* Go through the descriptors, checking their length and counting the
 650          * number of altsettings for each interface */
 651         n = 0;
 652         for ((buffer2 = buffer, size2 = size);
 653               size2 > 0;
 654              (buffer2 += header->bLength, size2 -= header->bLength)) {
 655 
 656                 if (size2 < sizeof(struct usb_descriptor_header)) {
 657                         dev_warn(ddev, "config %d descriptor has %d excess "
 658                             "byte%s, ignoring\n",
 659                             cfgno, size2, plural(size2));
 660                         break;
 661                 }
 662 
 663                 header = (struct usb_descriptor_header *) buffer2;
 664                 if ((header->bLength > size2) || (header->bLength < 2)) {
 665                         dev_warn(ddev, "config %d has an invalid descriptor "
 666                             "of length %d, skipping remainder of the config\n",
 667                             cfgno, header->bLength);
 668                         break;
 669                 }
 670 
 671                 if (header->bDescriptorType == USB_DT_INTERFACE) {
 672                         struct usb_interface_descriptor *d;
 673                         int inum;
 674 
 675                         d = (struct usb_interface_descriptor *) header;
 676                         if (d->bLength < USB_DT_INTERFACE_SIZE) {
 677                                 dev_warn(ddev, "config %d has an invalid "
 678                                     "interface descriptor of length %d, "
 679                                     "skipping\n", cfgno, d->bLength);
 680                                 continue;
 681                         }
 682 
 683                         inum = d->bInterfaceNumber;
 684 
 685                         if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 686                             n >= nintf_orig) {
 687                                 dev_warn(ddev, "config %d has more interface "
 688                                     "descriptors, than it declares in "
 689                                     "bNumInterfaces, ignoring interface "
 690                                     "number: %d\n", cfgno, inum);
 691                                 continue;
 692                         }
 693 
 694                         if (inum >= nintf_orig)
 695                                 dev_warn(ddev, "config %d has an invalid "
 696                                     "interface number: %d but max is %d\n",
 697                                     cfgno, inum, nintf_orig - 1);
 698 
 699                         /* Have we already encountered this interface?
 700                          * Count its altsettings */
 701                         for (i = 0; i < n; ++i) {
 702                                 if (inums[i] == inum)
 703                                         break;
 704                         }
 705                         if (i < n) {
 706                                 if (nalts[i] < 255)
 707                                         ++nalts[i];
 708                         } else if (n < USB_MAXINTERFACES) {
 709                                 inums[n] = inum;
 710                                 nalts[n] = 1;
 711                                 ++n;
 712                         }
 713 
 714                 } else if (header->bDescriptorType ==
 715                                 USB_DT_INTERFACE_ASSOCIATION) {
 716                         struct usb_interface_assoc_descriptor *d;
 717 
 718                         d = (struct usb_interface_assoc_descriptor *)header;
 719                         if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
 720                                 dev_warn(ddev,
 721                                          "config %d has an invalid interface association descriptor of length %d, skipping\n",
 722                                          cfgno, d->bLength);
 723                                 continue;
 724                         }
 725 
 726                         if (iad_num == USB_MAXIADS) {
 727                                 dev_warn(ddev, "found more Interface "
 728                                                "Association Descriptors "
 729                                                "than allocated for in "
 730                                                "configuration %d\n", cfgno);
 731                         } else {
 732                                 config->intf_assoc[iad_num] = d;
 733                                 iad_num++;
 734                         }
 735 
 736                 } else if (header->bDescriptorType == USB_DT_DEVICE ||
 737                             header->bDescriptorType == USB_DT_CONFIG)
 738                         dev_warn(ddev, "config %d contains an unexpected "
 739                             "descriptor of type 0x%X, skipping\n",
 740                             cfgno, header->bDescriptorType);
 741 
 742         }       /* for ((buffer2 = buffer, size2 = size); ...) */
 743         size = buffer2 - buffer;
 744         config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 745 
 746         if (n != nintf)
 747                 dev_warn(ddev, "config %d has %d interface%s, different from "
 748                     "the descriptor's value: %d\n",
 749                     cfgno, n, plural(n), nintf_orig);
 750         else if (n == 0)
 751                 dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
 752         config->desc.bNumInterfaces = nintf = n;
 753 
 754         /* Check for missing interface numbers */
 755         for (i = 0; i < nintf; ++i) {
 756                 for (j = 0; j < nintf; ++j) {
 757                         if (inums[j] == i)
 758                                 break;
 759                 }
 760                 if (j >= nintf)
 761                         dev_warn(ddev, "config %d has no interface number "
 762                             "%d\n", cfgno, i);
 763         }
 764 
 765         /* Allocate the usb_interface_caches and altsetting arrays */
 766         for (i = 0; i < nintf; ++i) {
 767                 j = nalts[i];
 768                 if (j > USB_MAXALTSETTING) {
 769                         dev_warn(ddev, "too many alternate settings for "
 770                             "config %d interface %d: %d, "
 771                             "using maximum allowed: %d\n",
 772                             cfgno, inums[i], j, USB_MAXALTSETTING);
 773                         nalts[i] = j = USB_MAXALTSETTING;
 774                 }
 775 
 776                 intfc = kzalloc(struct_size(intfc, altsetting, j), GFP_KERNEL);
 777                 config->intf_cache[i] = intfc;
 778                 if (!intfc)
 779                         return -ENOMEM;
 780                 kref_init(&intfc->ref);
 781         }
 782 
 783         /* FIXME: parse the BOS descriptor */
 784 
 785         /* Skip over any Class Specific or Vendor Specific descriptors;
 786          * find the first interface descriptor */
 787         config->extra = buffer;
 788         i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 789             USB_DT_INTERFACE, &n);
 790         config->extralen = i;
 791         if (n > 0)
 792                 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 793                     n, plural(n), "configuration");
 794         buffer += i;
 795         size -= i;
 796 
 797         /* Parse all the interface/altsetting descriptors */
 798         while (size > 0) {
 799                 retval = usb_parse_interface(ddev, cfgno, config,
 800                     buffer, size, inums, nalts);
 801                 if (retval < 0)
 802                         return retval;
 803 
 804                 buffer += retval;
 805                 size -= retval;
 806         }
 807 
 808         /* Check for missing altsettings */
 809         for (i = 0; i < nintf; ++i) {
 810                 intfc = config->intf_cache[i];
 811                 for (j = 0; j < intfc->num_altsetting; ++j) {
 812                         for (n = 0; n < intfc->num_altsetting; ++n) {
 813                                 if (intfc->altsetting[n].desc.
 814                                     bAlternateSetting == j)
 815                                         break;
 816                         }
 817                         if (n >= intfc->num_altsetting)
 818                                 dev_warn(ddev, "config %d interface %d has no "
 819                                     "altsetting %d\n", cfgno, inums[i], j);
 820                 }
 821         }
 822 
 823         return 0;
 824 }
 825 
 826 /* hub-only!! ... and only exported for reset/reinit path.
 827  * otherwise used internally on disconnect/destroy path
 828  */
 829 void usb_destroy_configuration(struct usb_device *dev)
 830 {
 831         int c, i;
 832 
 833         if (!dev->config)
 834                 return;
 835 
 836         if (dev->rawdescriptors) {
 837                 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 838                         kfree(dev->rawdescriptors[i]);
 839 
 840                 kfree(dev->rawdescriptors);
 841                 dev->rawdescriptors = NULL;
 842         }
 843 
 844         for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 845                 struct usb_host_config *cf = &dev->config[c];
 846 
 847                 kfree(cf->string);
 848                 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 849                         if (cf->intf_cache[i])
 850                                 kref_put(&cf->intf_cache[i]->ref,
 851                                           usb_release_interface_cache);
 852                 }
 853         }
 854         kfree(dev->config);
 855         dev->config = NULL;
 856 }
 857 
 858 
 859 /*
 860  * Get the USB config descriptors, cache and parse'em
 861  *
 862  * hub-only!! ... and only in reset path, or usb_new_device()
 863  * (used by real hubs and virtual root hubs)
 864  */
 865 int usb_get_configuration(struct usb_device *dev)
 866 {
 867         struct device *ddev = &dev->dev;
 868         int ncfg = dev->descriptor.bNumConfigurations;
 869         int result = -ENOMEM;
 870         unsigned int cfgno, length;
 871         unsigned char *bigbuffer;
 872         struct usb_config_descriptor *desc;
 873 
 874         if (ncfg > USB_MAXCONFIG) {
 875                 dev_warn(ddev, "too many configurations: %d, "
 876                     "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 877                 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 878         }
 879 
 880         if (ncfg < 1) {
 881                 dev_err(ddev, "no configurations\n");
 882                 return -EINVAL;
 883         }
 884 
 885         length = ncfg * sizeof(struct usb_host_config);
 886         dev->config = kzalloc(length, GFP_KERNEL);
 887         if (!dev->config)
 888                 goto err2;
 889 
 890         length = ncfg * sizeof(char *);
 891         dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 892         if (!dev->rawdescriptors)
 893                 goto err2;
 894 
 895         desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 896         if (!desc)
 897                 goto err2;
 898 
 899         for (cfgno = 0; cfgno < ncfg; cfgno++) {
 900                 /* We grab just the first descriptor so we know how long
 901                  * the whole configuration is */
 902                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 903                     desc, USB_DT_CONFIG_SIZE);
 904                 if (result < 0) {
 905                         dev_err(ddev, "unable to read config index %d "
 906                             "descriptor/%s: %d\n", cfgno, "start", result);
 907                         if (result != -EPIPE)
 908                                 goto err;
 909                         dev_err(ddev, "chopping to %d config(s)\n", cfgno);
 910                         dev->descriptor.bNumConfigurations = cfgno;
 911                         break;
 912                 } else if (result < 4) {
 913                         dev_err(ddev, "config index %d descriptor too short "
 914                             "(expected %i, got %i)\n", cfgno,
 915                             USB_DT_CONFIG_SIZE, result);
 916                         result = -EINVAL;
 917                         goto err;
 918                 }
 919                 length = max((int) le16_to_cpu(desc->wTotalLength),
 920                     USB_DT_CONFIG_SIZE);
 921 
 922                 /* Now that we know the length, get the whole thing */
 923                 bigbuffer = kmalloc(length, GFP_KERNEL);
 924                 if (!bigbuffer) {
 925                         result = -ENOMEM;
 926                         goto err;
 927                 }
 928 
 929                 if (dev->quirks & USB_QUIRK_DELAY_INIT)
 930                         msleep(200);
 931 
 932                 result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 933                     bigbuffer, length);
 934                 if (result < 0) {
 935                         dev_err(ddev, "unable to read config index %d "
 936                             "descriptor/%s\n", cfgno, "all");
 937                         kfree(bigbuffer);
 938                         goto err;
 939                 }
 940                 if (result < length) {
 941                         dev_warn(ddev, "config index %d descriptor too short "
 942                             "(expected %i, got %i)\n", cfgno, length, result);
 943                         length = result;
 944                 }
 945 
 946                 dev->rawdescriptors[cfgno] = bigbuffer;
 947 
 948                 result = usb_parse_configuration(dev, cfgno,
 949                     &dev->config[cfgno], bigbuffer, length);
 950                 if (result < 0) {
 951                         ++cfgno;
 952                         goto err;
 953                 }
 954         }
 955 
 956 err:
 957         kfree(desc);
 958         dev->descriptor.bNumConfigurations = cfgno;
 959 err2:
 960         if (result == -ENOMEM)
 961                 dev_err(ddev, "out of memory\n");
 962         return result;
 963 }
 964 
 965 void usb_release_bos_descriptor(struct usb_device *dev)
 966 {
 967         if (dev->bos) {
 968                 kfree(dev->bos->desc);
 969                 kfree(dev->bos);
 970                 dev->bos = NULL;
 971         }
 972 }
 973 
 974 static const __u8 bos_desc_len[256] = {
 975         [USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
 976         [USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
 977         [USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
 978         [USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
 979         [CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
 980         [USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
 981 };
 982 
 983 /* Get BOS descriptor set */
 984 int usb_get_bos_descriptor(struct usb_device *dev)
 985 {
 986         struct device *ddev = &dev->dev;
 987         struct usb_bos_descriptor *bos;
 988         struct usb_dev_cap_header *cap;
 989         struct usb_ssp_cap_descriptor *ssp_cap;
 990         unsigned char *buffer, *buffer0;
 991         int length, total_len, num, i, ssac;
 992         __u8 cap_type;
 993         int ret;
 994 
 995         bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
 996         if (!bos)
 997                 return -ENOMEM;
 998 
 999         /* Get BOS descriptor */
1000         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
1001         if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) {
1002                 dev_err(ddev, "unable to get BOS descriptor or descriptor too short\n");
1003                 if (ret >= 0)
1004                         ret = -ENOMSG;
1005                 kfree(bos);
1006                 return ret;
1007         }
1008 
1009         length = bos->bLength;
1010         total_len = le16_to_cpu(bos->wTotalLength);
1011         num = bos->bNumDeviceCaps;
1012         kfree(bos);
1013         if (total_len < length)
1014                 return -EINVAL;
1015 
1016         dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
1017         if (!dev->bos)
1018                 return -ENOMEM;
1019 
1020         /* Now let's get the whole BOS descriptor set */
1021         buffer = kzalloc(total_len, GFP_KERNEL);
1022         if (!buffer) {
1023                 ret = -ENOMEM;
1024                 goto err;
1025         }
1026         dev->bos->desc = (struct usb_bos_descriptor *)buffer;
1027 
1028         ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
1029         if (ret < total_len) {
1030                 dev_err(ddev, "unable to get BOS descriptor set\n");
1031                 if (ret >= 0)
1032                         ret = -ENOMSG;
1033                 goto err;
1034         }
1035 
1036         buffer0 = buffer;
1037         total_len -= length;
1038         buffer += length;
1039 
1040         for (i = 0; i < num; i++) {
1041                 cap = (struct usb_dev_cap_header *)buffer;
1042 
1043                 if (total_len < sizeof(*cap) || total_len < cap->bLength) {
1044                         dev->bos->desc->bNumDeviceCaps = i;
1045                         break;
1046                 }
1047                 cap_type = cap->bDevCapabilityType;
1048                 length = cap->bLength;
1049                 if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
1050                         dev->bos->desc->bNumDeviceCaps = i;
1051                         break;
1052                 }
1053 
1054                 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
1055                         dev_warn(ddev, "descriptor type invalid, skip\n");
1056                         continue;
1057                 }
1058 
1059                 switch (cap_type) {
1060                 case USB_CAP_TYPE_WIRELESS_USB:
1061                         /* Wireless USB cap descriptor is handled by wusb */
1062                         break;
1063                 case USB_CAP_TYPE_EXT:
1064                         dev->bos->ext_cap =
1065                                 (struct usb_ext_cap_descriptor *)buffer;
1066                         break;
1067                 case USB_SS_CAP_TYPE:
1068                         dev->bos->ss_cap =
1069                                 (struct usb_ss_cap_descriptor *)buffer;
1070                         break;
1071                 case USB_SSP_CAP_TYPE:
1072                         ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
1073                         ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
1074                                 USB_SSP_SUBLINK_SPEED_ATTRIBS);
1075                         if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
1076                                 dev->bos->ssp_cap = ssp_cap;
1077                         break;
1078                 case CONTAINER_ID_TYPE:
1079                         dev->bos->ss_id =
1080                                 (struct usb_ss_container_id_descriptor *)buffer;
1081                         break;
1082                 case USB_PTM_CAP_TYPE:
1083                         dev->bos->ptm_cap =
1084                                 (struct usb_ptm_cap_descriptor *)buffer;
1085                 default:
1086                         break;
1087                 }
1088 
1089                 total_len -= length;
1090                 buffer += length;
1091         }
1092         dev->bos->desc->wTotalLength = cpu_to_le16(buffer - buffer0);
1093 
1094         return 0;
1095 
1096 err:
1097         usb_release_bos_descriptor(dev);
1098         return ret;
1099 }
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/usb/core/config.c

DEFINITIONS
