config.c

   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/string_choices.h>
  13#include <linux/device.h>
  14#include <asm/byteorder.h>
  15#include "usb.h"
  16
  17
  18#define USB_MAXALTSETTING		128	/* Hard limit */
  19
  20#define USB_MAXCONFIG			8	/* Arbitrary limit */
  21
  22static 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
  46static 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_notice(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
  67static void usb_parse_eusb2_isoc_endpoint_companion(struct device *ddev,
  68		int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
  69		unsigned char *buffer, int size)
  70{
  71	struct usb_eusb2_isoc_ep_comp_descriptor *desc;
  72	struct usb_descriptor_header *h;
  73
  74	/*
  75	 * eUSB2 isochronous endpoint companion descriptor for this endpoint
  76	 * shall be declared before the next endpoint or interface descriptor
  77	 */
  78	while (size >= USB_DT_EUSB2_ISOC_EP_COMP_SIZE) {
  79		h = (struct usb_descriptor_header *)buffer;
  80
  81		if (h->bDescriptorType == USB_DT_EUSB2_ISOC_ENDPOINT_COMP) {
  82			desc = (struct usb_eusb2_isoc_ep_comp_descriptor *)buffer;
  83			ep->eusb2_isoc_ep_comp = *desc;
  84			return;
  85		}
  86		if (h->bDescriptorType == USB_DT_ENDPOINT ||
  87		    h->bDescriptorType == USB_DT_INTERFACE)
  88			break;
  89
  90		buffer += h->bLength;
  91		size -= h->bLength;
  92	}
  93
  94	dev_notice(ddev, "No eUSB2 isoc ep %d companion for config %d interface %d altsetting %d\n",
  95		   ep->desc.bEndpointAddress, cfgno, inum, asnum);
  96}
  97
  98static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
  99		int inum, int asnum, struct usb_host_endpoint *ep,
 100		unsigned char *buffer, int size)
 101{
 102	struct usb_ss_ep_comp_descriptor *desc;
 103	int max_tx;
 104
 105	/* The SuperSpeed endpoint companion descriptor is supposed to
 106	 * be the first thing immediately following the endpoint descriptor.
 107	 */
 108	desc = (struct usb_ss_ep_comp_descriptor *) buffer;
 109
 110	if (size < USB_DT_SS_EP_COMP_SIZE) {
 111		dev_notice(ddev,
 112			   "invalid SuperSpeed endpoint companion descriptor "
 113			   "of length %d, skipping\n", size);
 114		return;
 115	}
 116
 117	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP) {
 118		dev_notice(ddev, "No SuperSpeed endpoint companion for config %d "
 119				" interface %d altsetting %d ep %d: "
 120				"using minimum values\n",
 121				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 122
 123		/* Fill in some default values.
 124		 * Leave bmAttributes as zero, which will mean no streams for
 125		 * bulk, and isoc won't support multiple bursts of packets.
 126		 * With bursts of only one packet, and a Mult of 1, the max
 127		 * amount of data moved per endpoint service interval is one
 128		 * packet.
 129		 */
 130		ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
 131		ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
 132		if (usb_endpoint_xfer_isoc(&ep->desc) ||
 133				usb_endpoint_xfer_int(&ep->desc))
 134			ep->ss_ep_comp.wBytesPerInterval =
 135					ep->desc.wMaxPacketSize;
 136		return;
 137	}
 138	buffer += desc->bLength;
 139	size -= desc->bLength;
 140	memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 141
 142	/* Check the various values */
 143	if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 144		dev_notice(ddev, "Control endpoint with bMaxBurst = %d in "
 145				"config %d interface %d altsetting %d ep %d: "
 146				"setting to zero\n", desc->bMaxBurst,
 147				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 148		ep->ss_ep_comp.bMaxBurst = 0;
 149	} else if (desc->bMaxBurst > 15) {
 150		dev_notice(ddev, "Endpoint with bMaxBurst = %d in "
 151				"config %d interface %d altsetting %d ep %d: "
 152				"setting to 15\n", desc->bMaxBurst,
 153				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 154		ep->ss_ep_comp.bMaxBurst = 15;
 155	}
 156
 157	if ((usb_endpoint_xfer_control(&ep->desc) ||
 158			usb_endpoint_xfer_int(&ep->desc)) &&
 159				desc->bmAttributes != 0) {
 160		dev_notice(ddev, "%s endpoint with bmAttributes = %d in "
 161				"config %d interface %d altsetting %d ep %d: "
 162				"setting to zero\n",
 163				usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
 164				desc->bmAttributes,
 165				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 166		ep->ss_ep_comp.bmAttributes = 0;
 167	} else if (usb_endpoint_xfer_bulk(&ep->desc) &&
 168			desc->bmAttributes > 16) {
 169		dev_notice(ddev, "Bulk endpoint with more than 65536 streams in "
 170				"config %d interface %d altsetting %d ep %d: "
 171				"setting to max\n",
 172				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 173		ep->ss_ep_comp.bmAttributes = 16;
 174	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&
 175		   !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
 176		   USB_SS_MULT(desc->bmAttributes) > 3) {
 177		dev_notice(ddev, "Isoc endpoint has Mult of %d in "
 178				"config %d interface %d altsetting %d ep %d: "
 179				"setting to 3\n",
 180				USB_SS_MULT(desc->bmAttributes),
 181				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 182		ep->ss_ep_comp.bmAttributes = 2;
 183	}
 184
 185	if (usb_endpoint_xfer_isoc(&ep->desc))
 186		max_tx = (desc->bMaxBurst + 1) *
 187			(USB_SS_MULT(desc->bmAttributes)) *
 188			usb_endpoint_maxp(&ep->desc);
 189	else if (usb_endpoint_xfer_int(&ep->desc))
 190		max_tx = usb_endpoint_maxp(&ep->desc) *
 191			(desc->bMaxBurst + 1);
 192	else
 193		max_tx = 999999;
 194	if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
 195		dev_notice(ddev, "%s endpoint with wBytesPerInterval of %d in "
 196				"config %d interface %d altsetting %d ep %d: "
 197				"setting to %d\n",
 198				usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
 199				le16_to_cpu(desc->wBytesPerInterval),
 200				cfgno, inum, asnum, ep->desc.bEndpointAddress,
 201				max_tx);
 202		ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
 203	}
 204	/* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
 205	if (usb_endpoint_xfer_isoc(&ep->desc) &&
 206	    USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
 207		usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 208							ep, buffer, size);
 209}
 210
 211static const unsigned short low_speed_maxpacket_maxes[4] = {
 212	[USB_ENDPOINT_XFER_CONTROL] = 8,
 213	[USB_ENDPOINT_XFER_ISOC] = 0,
 214	[USB_ENDPOINT_XFER_BULK] = 0,
 215	[USB_ENDPOINT_XFER_INT] = 8,
 216};
 217static const unsigned short full_speed_maxpacket_maxes[4] = {
 218	[USB_ENDPOINT_XFER_CONTROL] = 64,
 219	[USB_ENDPOINT_XFER_ISOC] = 1023,
 220	[USB_ENDPOINT_XFER_BULK] = 64,
 221	[USB_ENDPOINT_XFER_INT] = 64,
 222};
 223static const unsigned short high_speed_maxpacket_maxes[4] = {
 224	[USB_ENDPOINT_XFER_CONTROL] = 64,
 225	[USB_ENDPOINT_XFER_ISOC] = 1024,
 226
 227	/* Bulk should be 512, but some devices use 1024: we will warn below */
 228	[USB_ENDPOINT_XFER_BULK] = 1024,
 229	[USB_ENDPOINT_XFER_INT] = 1024,
 230};
 231static const unsigned short super_speed_maxpacket_maxes[4] = {
 232	[USB_ENDPOINT_XFER_CONTROL] = 512,
 233	[USB_ENDPOINT_XFER_ISOC] = 1024,
 234	[USB_ENDPOINT_XFER_BULK] = 1024,
 235	[USB_ENDPOINT_XFER_INT] = 1024,
 236};
 237
 238static bool endpoint_is_duplicate(struct usb_endpoint_descriptor *e1,
 239		struct usb_endpoint_descriptor *e2)
 240{
 241	if (e1->bEndpointAddress == e2->bEndpointAddress)
 242		return true;
 243
 244	if (usb_endpoint_xfer_control(e1) || usb_endpoint_xfer_control(e2)) {
 245		if (usb_endpoint_num(e1) == usb_endpoint_num(e2))
 246			return true;
 247	}
 248
 249	return false;
 250}
 251
 252/*
 253 * Check for duplicate endpoint addresses in other interfaces and in the
 254 * altsetting currently being parsed.
 255 */
 256static bool config_endpoint_is_duplicate(struct usb_host_config *config,
 257		int inum, int asnum, struct usb_endpoint_descriptor *d)
 258{
 259	struct usb_endpoint_descriptor *epd;
 260	struct usb_interface_cache *intfc;
 261	struct usb_host_interface *alt;
 262	int i, j, k;
 263
 264	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 265		intfc = config->intf_cache[i];
 266
 267		for (j = 0; j < intfc->num_altsetting; ++j) {
 268			alt = &intfc->altsetting[j];
 269
 270			if (alt->desc.bInterfaceNumber == inum &&
 271					alt->desc.bAlternateSetting != asnum)
 272				continue;
 273
 274			for (k = 0; k < alt->desc.bNumEndpoints; ++k) {
 275				epd = &alt->endpoint[k].desc;
 276
 277				if (endpoint_is_duplicate(epd, d))
 278					return true;
 279			}
 280		}
 281	}
 282
 283	return false;
 284}
 285
 286static int usb_parse_endpoint(struct device *ddev, int cfgno,
 287		struct usb_host_config *config, int inum, int asnum,
 288		struct usb_host_interface *ifp, int num_ep,
 289		unsigned char *buffer, int size)
 290{
 291	struct usb_device *udev = to_usb_device(ddev);
 292	unsigned char *buffer0 = buffer;
 293	struct usb_endpoint_descriptor *d;
 294	struct usb_host_endpoint *endpoint;
 295	int n, i, j, retval;
 296	unsigned int maxp;
 297	const unsigned short *maxpacket_maxes;
 298	u16 bcdUSB;
 299
 300	d = (struct usb_endpoint_descriptor *) buffer;
 301	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
 302	buffer += d->bLength;
 303	size -= d->bLength;
 304
 305	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
 306		n = USB_DT_ENDPOINT_AUDIO_SIZE;
 307	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
 308		n = USB_DT_ENDPOINT_SIZE;
 309	else {
 310		dev_notice(ddev, "config %d interface %d altsetting %d has an "
 311		    "invalid endpoint descriptor of length %d, skipping\n",
 312		    cfgno, inum, asnum, d->bLength);
 313		goto skip_to_next_endpoint_or_interface_descriptor;
 314	}
 315
 316	i = usb_endpoint_num(d);
 317	if (i == 0) {
 318		dev_notice(ddev, "config %d interface %d altsetting %d has an "
 319		    "invalid descriptor for endpoint zero, skipping\n",
 320		    cfgno, inum, asnum);
 321		goto skip_to_next_endpoint_or_interface_descriptor;
 322	}
 323
 324	/* Only store as many endpoints as we have room for */
 325	if (ifp->desc.bNumEndpoints >= num_ep)
 326		goto skip_to_next_endpoint_or_interface_descriptor;
 327
 328	/* Save a copy of the descriptor and use it instead of the original */
 329	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 330	memcpy(&endpoint->desc, d, n);
 331	d = &endpoint->desc;
 332
 333	/* Clear the reserved bits in bEndpointAddress */
 334	i = d->bEndpointAddress &
 335			(USB_ENDPOINT_DIR_MASK | USB_ENDPOINT_NUMBER_MASK);
 336	if (i != d->bEndpointAddress) {
 337		dev_notice(ddev, "config %d interface %d altsetting %d has an endpoint descriptor with address 0x%X, changing to 0x%X\n",
 338		    cfgno, inum, asnum, d->bEndpointAddress, i);
 339		endpoint->desc.bEndpointAddress = i;
 340	}
 341
 342	/* Check for duplicate endpoint addresses */
 343	if (config_endpoint_is_duplicate(config, inum, asnum, d)) {
 344		dev_notice(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
 345				cfgno, inum, asnum, d->bEndpointAddress);
 346		goto skip_to_next_endpoint_or_interface_descriptor;
 347	}
 348
 349	/* Ignore some endpoints */
 350	if (udev->quirks & USB_QUIRK_ENDPOINT_IGNORE) {
 351		if (usb_endpoint_is_ignored(udev, ifp, d)) {
 352			dev_notice(ddev, "config %d interface %d altsetting %d has an ignored endpoint with address 0x%X, skipping\n",
 353					cfgno, inum, asnum,
 354					d->bEndpointAddress);
 355			goto skip_to_next_endpoint_or_interface_descriptor;
 356		}
 357	}
 358
 359	/* Accept this endpoint */
 360	++ifp->desc.bNumEndpoints;
 361	INIT_LIST_HEAD(&endpoint->urb_list);
 362
 363	/*
 364	 * Fix up bInterval values outside the legal range.
 365	 * Use 10 or 8 ms if no proper value can be guessed.
 366	 */
 367	i = 0;		/* i = min, j = max, n = default */
 368	j = 255;
 369	if (usb_endpoint_xfer_int(d)) {
 370		i = 1;
 371		switch (udev->speed) {
 372		case USB_SPEED_SUPER_PLUS:
 373		case USB_SPEED_SUPER:
 374		case USB_SPEED_HIGH:
 375			/*
 376			 * Many device manufacturers are using full-speed
 377			 * bInterval values in high-speed interrupt endpoint
 378			 * descriptors. Try to fix those and fall back to an
 379			 * 8-ms default value otherwise.
 380			 */
 381			n = fls(d->bInterval*8);
 382			if (n == 0)
 383				n = 7;	/* 8 ms = 2^(7-1) uframes */
 384			j = 16;
 385
 386			/*
 387			 * Adjust bInterval for quirked devices.
 388			 */
 389			/*
 390			 * This quirk fixes bIntervals reported in ms.
 391			 */
 392			if (udev->quirks & USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 393				n = clamp(fls(d->bInterval) + 3, i, j);
 394				i = j = n;
 395			}
 396			/*
 397			 * This quirk fixes bIntervals reported in
 398			 * linear microframes.
 399			 */
 400			if (udev->quirks & USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 401				n = clamp(fls(d->bInterval), i, j);
 402				i = j = n;
 403			}
 404			break;
 405		default:		/* USB_SPEED_FULL or _LOW */
 406			/*
 407			 * For low-speed, 10 ms is the official minimum.
 408			 * But some "overclocked" devices might want faster
 409			 * polling so we'll allow it.
 410			 */
 411			n = 10;
 412			break;
 413		}
 414	} else if (usb_endpoint_xfer_isoc(d)) {
 415		i = 1;
 416		j = 16;
 417		switch (udev->speed) {
 418		case USB_SPEED_HIGH:
 419			n = 7;		/* 8 ms = 2^(7-1) uframes */
 420			break;
 421		default:		/* USB_SPEED_FULL */
 422			n = 4;		/* 8 ms = 2^(4-1) frames */
 423			break;
 424		}
 425	}
 426	if (d->bInterval < i || d->bInterval > j) {
 427		dev_notice(ddev, "config %d interface %d altsetting %d "
 428		    "endpoint 0x%X has an invalid bInterval %d, "
 429		    "changing to %d\n",
 430		    cfgno, inum, asnum,
 431		    d->bEndpointAddress, d->bInterval, n);
 432		endpoint->desc.bInterval = n;
 433	}
 434
 435	/* Some buggy low-speed devices have Bulk endpoints, which is
 436	 * explicitly forbidden by the USB spec.  In an attempt to make
 437	 * them usable, we will try treating them as Interrupt endpoints.
 438	 */
 439	if (udev->speed == USB_SPEED_LOW && usb_endpoint_xfer_bulk(d)) {
 440		dev_notice(ddev, "config %d interface %d altsetting %d "
 441		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
 442		    cfgno, inum, asnum, d->bEndpointAddress);
 443		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 444		endpoint->desc.bInterval = 1;
 445		if (usb_endpoint_maxp(&endpoint->desc) > 8)
 446			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 447	}
 448
 449	/*
 450	 * Validate the wMaxPacketSize field.
 451	 * eUSB2 devices (see USB 2.0 Double Isochronous IN ECN 9.6.6 Endpoint)
 452	 * and devices with isochronous endpoints in altsetting 0 (see USB 2.0
 453	 * end of section 5.6.3) have wMaxPacketSize = 0.
 454	 * So don't warn about those.
 455	 */
 456	maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize);
 457
 458	if (maxp == 0 && bcdUSB != 0x0220 &&
 459	    !(usb_endpoint_xfer_isoc(d) && asnum == 0))
 460		dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
 461		    cfgno, inum, asnum, d->bEndpointAddress);
 462
 463	/* Find the highest legal maxpacket size for this endpoint */
 464	i = 0;		/* additional transactions per microframe */
 465	switch (udev->speed) {
 466	case USB_SPEED_LOW:
 467		maxpacket_maxes = low_speed_maxpacket_maxes;
 468		break;
 469	case USB_SPEED_FULL:
 470		maxpacket_maxes = full_speed_maxpacket_maxes;
 471		break;
 472	case USB_SPEED_HIGH:
 473		/* Multiple-transactions bits are allowed only for HS periodic endpoints */
 474		if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 475			i = maxp & USB_EP_MAXP_MULT_MASK;
 476			maxp &= ~i;
 477		}
 478		fallthrough;
 479	default:
 480		maxpacket_maxes = high_speed_maxpacket_maxes;
 481		break;
 482	case USB_SPEED_SUPER:
 483	case USB_SPEED_SUPER_PLUS:
 484		maxpacket_maxes = super_speed_maxpacket_maxes;
 485		break;
 486	}
 487	j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 488
 489	if (maxp > j) {
 490		dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 491		    cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 492		maxp = j;
 493		endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 494	}
 495
 496	/*
 497	 * Some buggy high speed devices have bulk endpoints using
 498	 * maxpacket sizes other than 512.  High speed HCDs may not
 499	 * be able to handle that particular bug, so let's warn...
 500	 */
 501	if (udev->speed == USB_SPEED_HIGH && usb_endpoint_xfer_bulk(d)) {
 502		if (maxp != 512)
 503			dev_notice(ddev, "config %d interface %d altsetting %d "
 504				"bulk endpoint 0x%X has invalid maxpacket %d\n",
 505				cfgno, inum, asnum, d->bEndpointAddress,
 506				maxp);
 507	}
 508
 509	/* Parse a possible eUSB2 periodic endpoint companion descriptor */
 510	if (udev->speed == USB_SPEED_HIGH && bcdUSB == 0x0220 &&
 511	    !le16_to_cpu(d->wMaxPacketSize) && usb_endpoint_is_isoc_in(d))
 512		usb_parse_eusb2_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
 513							endpoint, buffer, size);
 514
 515	/* Parse a possible SuperSpeed endpoint companion descriptor */
 516	if (udev->speed >= USB_SPEED_SUPER)
 517		usb_parse_ss_endpoint_companion(ddev, cfgno,
 518				inum, asnum, endpoint, buffer, size);
 519
 520	/* Skip over any Class Specific or Vendor Specific descriptors;
 521	 * find the next endpoint or interface descriptor */
 522	endpoint->extra = buffer;
 523	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 524			USB_DT_INTERFACE, &n);
 525	endpoint->extralen = i;
 526	retval = buffer - buffer0 + i;
 527	if (n > 0)
 528		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 529		    n, str_plural(n), "endpoint");
 530	return retval;
 531
 532skip_to_next_endpoint_or_interface_descriptor:
 533	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 534	    USB_DT_INTERFACE, NULL);
 535	return buffer - buffer0 + i;
 536}
 537
 538void usb_release_interface_cache(struct kref *ref)
 539{
 540	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 541	int j;
 542
 543	for (j = 0; j < intfc->num_altsetting; j++) {
 544		struct usb_host_interface *alt = &intfc->altsetting[j];
 545
 546		kfree(alt->endpoint);
 547		kfree(alt->string);
 548	}
 549	kfree(intfc);
 550}
 551
 552static int usb_parse_interface(struct device *ddev, int cfgno,
 553    struct usb_host_config *config, unsigned char *buffer, int size,
 554    u8 inums[], u8 nalts[])
 555{
 556	unsigned char *buffer0 = buffer;
 557	struct usb_interface_descriptor	*d;
 558	int inum, asnum;
 559	struct usb_interface_cache *intfc;
 560	struct usb_host_interface *alt;
 561	int i, n;
 562	int len, retval;
 563	int num_ep, num_ep_orig;
 564
 565	d = (struct usb_interface_descriptor *) buffer;
 566	buffer += d->bLength;
 567	size -= d->bLength;
 568
 569	if (d->bLength < USB_DT_INTERFACE_SIZE)
 570		goto skip_to_next_interface_descriptor;
 571
 572	/* Which interface entry is this? */
 573	intfc = NULL;
 574	inum = d->bInterfaceNumber;
 575	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 576		if (inums[i] == inum) {
 577			intfc = config->intf_cache[i];
 578			break;
 579		}
 580	}
 581	if (!intfc || intfc->num_altsetting >= nalts[i])
 582		goto skip_to_next_interface_descriptor;
 583
 584	/* Check for duplicate altsetting entries */
 585	asnum = d->bAlternateSetting;
 586	for ((i = 0, alt = &intfc->altsetting[0]);
 587	      i < intfc->num_altsetting;
 588	     (++i, ++alt)) {
 589		if (alt->desc.bAlternateSetting == asnum) {
 590			dev_notice(ddev, "Duplicate descriptor for config %d "
 591			    "interface %d altsetting %d, skipping\n",
 592			    cfgno, inum, asnum);
 593			goto skip_to_next_interface_descriptor;
 594		}
 595	}
 596
 597	++intfc->num_altsetting;
 598	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 599
 600	/* Skip over any Class Specific or Vendor Specific descriptors;
 601	 * find the first endpoint or interface descriptor */
 602	alt->extra = buffer;
 603	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 604	    USB_DT_INTERFACE, &n);
 605	alt->extralen = i;
 606	if (n > 0)
 607		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 608		    n, str_plural(n), "interface");
 609	buffer += i;
 610	size -= i;
 611
 612	/* Allocate space for the right(?) number of endpoints */
 613	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 614	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
 615	if (num_ep > USB_MAXENDPOINTS) {
 616		dev_notice(ddev, "too many endpoints for config %d interface %d "
 617		    "altsetting %d: %d, using maximum allowed: %d\n",
 618		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 619		num_ep = USB_MAXENDPOINTS;
 620	}
 621
 622	if (num_ep > 0) {
 623		/* Can't allocate 0 bytes */
 624		len = sizeof(struct usb_host_endpoint) * num_ep;
 625		alt->endpoint = kzalloc(len, GFP_KERNEL);
 626		if (!alt->endpoint)
 627			return -ENOMEM;
 628	}
 629
 630	/* Parse all the endpoint descriptors */
 631	n = 0;
 632	while (size > 0) {
 633		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 634		     == USB_DT_INTERFACE)
 635			break;
 636		retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
 637				alt, num_ep, buffer, size);
 638		if (retval < 0)
 639			return retval;
 640		++n;
 641
 642		buffer += retval;
 643		size -= retval;
 644	}
 645
 646	if (n != num_ep_orig)
 647		dev_notice(ddev, "config %d interface %d altsetting %d has %d "
 648		    "endpoint descriptor%s, different from the interface "
 649		    "descriptor's value: %d\n",
 650		    cfgno, inum, asnum, n, str_plural(n), num_ep_orig);
 651	return buffer - buffer0;
 652
 653skip_to_next_interface_descriptor:
 654	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 655	    USB_DT_INTERFACE, NULL);
 656	return buffer - buffer0 + i;
 657}
 658
 659static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 660    struct usb_host_config *config, unsigned char *buffer, int size)
 661{
 662	struct device *ddev = &dev->dev;
 663	unsigned char *buffer0 = buffer;
 664	int cfgno;
 665	int nintf, nintf_orig;
 666	int i, j, n;
 667	struct usb_interface_cache *intfc;
 668	unsigned char *buffer2;
 669	int size2;
 670	struct usb_descriptor_header *header;
 671	int retval;
 672	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 673	unsigned iad_num = 0;
 674
 675	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 676	nintf = nintf_orig = config->desc.bNumInterfaces;
 677	config->desc.bNumInterfaces = 0;	// Adjusted later
 678
 679	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 680	    config->desc.bLength < USB_DT_CONFIG_SIZE ||
 681	    config->desc.bLength > size) {
 682		dev_notice(ddev, "invalid descriptor for config index %d: "
 683		    "type = 0x%X, length = %d\n", cfgidx,
 684		    config->desc.bDescriptorType, config->desc.bLength);
 685		return -EINVAL;
 686	}
 687	cfgno = config->desc.bConfigurationValue;
 688
 689	buffer += config->desc.bLength;
 690	size -= config->desc.bLength;
 691
 692	if (nintf > USB_MAXINTERFACES) {
 693		dev_notice(ddev, "config %d has too many interfaces: %d, "
 694		    "using maximum allowed: %d\n",
 695		    cfgno, nintf, USB_MAXINTERFACES);
 696		nintf = USB_MAXINTERFACES;
 697	}
 698
 699	/* Go through the descriptors, checking their length and counting the
 700	 * number of altsettings for each interface */
 701	n = 0;
 702	for ((buffer2 = buffer, size2 = size);
 703	      size2 > 0;
 704	     (buffer2 += header->bLength, size2 -= header->bLength)) {
 705
 706		if (size2 < sizeof(struct usb_descriptor_header)) {
 707			dev_notice(ddev, "config %d descriptor has %d excess "
 708			    "byte%s, ignoring\n",
 709			    cfgno, size2, str_plural(size2));
 710			break;
 711		}
 712
 713		header = (struct usb_descriptor_header *) buffer2;
 714		if ((header->bLength > size2) || (header->bLength < 2)) {
 715			dev_notice(ddev, "config %d has an invalid descriptor "
 716			    "of length %d, skipping remainder of the config\n",
 717			    cfgno, header->bLength);
 718			break;
 719		}
 720
 721		if (header->bDescriptorType == USB_DT_INTERFACE) {
 722			struct usb_interface_descriptor *d;
 723			int inum;
 724
 725			d = (struct usb_interface_descriptor *) header;
 726			if (d->bLength < USB_DT_INTERFACE_SIZE) {
 727				dev_notice(ddev, "config %d has an invalid "
 728				    "interface descriptor of length %d, "
 729				    "skipping\n", cfgno, d->bLength);
 730				continue;
 731			}
 732
 733			inum = d->bInterfaceNumber;
 734
 735			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 736			    n >= nintf_orig) {
 737				dev_notice(ddev, "config %d has more interface "
 738				    "descriptors, than it declares in "
 739				    "bNumInterfaces, ignoring interface "
 740				    "number: %d\n", cfgno, inum);
 741				continue;
 742			}
 743
 744			if (inum >= nintf_orig)
 745				dev_notice(ddev, "config %d has an invalid "
 746				    "interface number: %d but max is %d\n",
 747				    cfgno, inum, nintf_orig - 1);
 748
 749			/* Have we already encountered this interface?
 750			 * Count its altsettings */
 751			for (i = 0; i < n; ++i) {
 752				if (inums[i] == inum)
 753					break;
 754			}
 755			if (i < n) {
 756				if (nalts[i] < 255)
 757					++nalts[i];
 758			} else if (n < USB_MAXINTERFACES) {
 759				inums[n] = inum;
 760				nalts[n] = 1;
 761				++n;
 762			}
 763
 764		} else if (header->bDescriptorType ==
 765				USB_DT_INTERFACE_ASSOCIATION) {
 766			struct usb_interface_assoc_descriptor *d;
 767
 768			d = (struct usb_interface_assoc_descriptor *)header;
 769			if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
 770				dev_notice(ddev,
 771					 "config %d has an invalid interface association descriptor of length %d, skipping\n",
 772					 cfgno, d->bLength);
 773				continue;
 774			}
 775
 776			if (iad_num == USB_MAXIADS) {
 777				dev_notice(ddev, "found more Interface "
 778					       "Association Descriptors "
 779					       "than allocated for in "
 780					       "configuration %d\n", cfgno);
 781			} else {
 782				config->intf_assoc[iad_num] = d;
 783				iad_num++;
 784			}
 785
 786		} else if (header->bDescriptorType == USB_DT_DEVICE ||
 787			    header->bDescriptorType == USB_DT_CONFIG)
 788			dev_notice(ddev, "config %d contains an unexpected "
 789			    "descriptor of type 0x%X, skipping\n",
 790			    cfgno, header->bDescriptorType);
 791
 792	}	/* for ((buffer2 = buffer, size2 = size); ...) */
 793	size = buffer2 - buffer;
 794	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 795
 796	if (n != nintf)
 797		dev_notice(ddev, "config %d has %d interface%s, different from "
 798		    "the descriptor's value: %d\n",
 799		    cfgno, n, str_plural(n), nintf_orig);
 800	else if (n == 0)
 801		dev_notice(ddev, "config %d has no interfaces?\n", cfgno);
 802	config->desc.bNumInterfaces = nintf = n;
 803
 804	/* Check for missing interface numbers */
 805	for (i = 0; i < nintf; ++i) {
 806		for (j = 0; j < nintf; ++j) {
 807			if (inums[j] == i)
 808				break;
 809		}
 810		if (j >= nintf)
 811			dev_notice(ddev, "config %d has no interface number "
 812			    "%d\n", cfgno, i);
 813	}
 814
 815	/* Allocate the usb_interface_caches and altsetting arrays */
 816	for (i = 0; i < nintf; ++i) {
 817		j = nalts[i];
 818		if (j > USB_MAXALTSETTING) {
 819			dev_notice(ddev, "too many alternate settings for "
 820			    "config %d interface %d: %d, "
 821			    "using maximum allowed: %d\n",
 822			    cfgno, inums[i], j, USB_MAXALTSETTING);
 823			nalts[i] = j = USB_MAXALTSETTING;
 824		}
 825
 826		intfc = kzalloc(struct_size(intfc, altsetting, j), GFP_KERNEL);
 827		config->intf_cache[i] = intfc;
 828		if (!intfc)
 829			return -ENOMEM;
 830		kref_init(&intfc->ref);
 831	}
 832
 833	/* FIXME: parse the BOS descriptor */
 834
 835	/* Skip over any Class Specific or Vendor Specific descriptors;
 836	 * find the first interface descriptor */
 837	config->extra = buffer;
 838	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 839	    USB_DT_INTERFACE, &n);
 840	config->extralen = i;
 841	if (n > 0)
 842		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 843		    n, str_plural(n), "configuration");
 844	buffer += i;
 845	size -= i;
 846
 847	/* Parse all the interface/altsetting descriptors */
 848	while (size > 0) {
 849		retval = usb_parse_interface(ddev, cfgno, config,
 850		    buffer, size, inums, nalts);
 851		if (retval < 0)
 852			return retval;
 853
 854		buffer += retval;
 855		size -= retval;
 856	}
 857
 858	/* Check for missing altsettings */
 859	for (i = 0; i < nintf; ++i) {
 860		intfc = config->intf_cache[i];
 861		for (j = 0; j < intfc->num_altsetting; ++j) {
 862			for (n = 0; n < intfc->num_altsetting; ++n) {
 863				if (intfc->altsetting[n].desc.
 864				    bAlternateSetting == j)
 865					break;
 866			}
 867			if (n >= intfc->num_altsetting)
 868				dev_notice(ddev, "config %d interface %d has no "
 869				    "altsetting %d\n", cfgno, inums[i], j);
 870		}
 871	}
 872
 873	return 0;
 874}
 875
 876/* hub-only!! ... and only exported for reset/reinit path.
 877 * otherwise used internally on disconnect/destroy path
 878 */
 879void usb_destroy_configuration(struct usb_device *dev)
 880{
 881	int c, i;
 882
 883	if (!dev->config)
 884		return;
 885
 886	if (dev->rawdescriptors) {
 887		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 888			kfree(dev->rawdescriptors[i]);
 889
 890		kfree(dev->rawdescriptors);
 891		dev->rawdescriptors = NULL;
 892	}
 893
 894	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 895		struct usb_host_config *cf = &dev->config[c];
 896
 897		kfree(cf->string);
 898		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 899			if (cf->intf_cache[i])
 900				kref_put(&cf->intf_cache[i]->ref,
 901					  usb_release_interface_cache);
 902		}
 903	}
 904	kfree(dev->config);
 905	dev->config = NULL;
 906}
 907
 908
 909/*
 910 * Get the USB config descriptors, cache and parse'em
 911 *
 912 * hub-only!! ... and only in reset path, or usb_new_device()
 913 * (used by real hubs and virtual root hubs)
 914 */
 915int usb_get_configuration(struct usb_device *dev)
 916{
 917	struct device *ddev = &dev->dev;
 918	int ncfg = dev->descriptor.bNumConfigurations;
 919	unsigned int cfgno, length;
 920	unsigned char *bigbuffer;
 921	struct usb_config_descriptor *desc;
 922	int result;
 923
 924	if (ncfg > USB_MAXCONFIG) {
 925		dev_notice(ddev, "too many configurations: %d, "
 926		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 927		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 928	}
 929
 930	if (ncfg < 1 && dev->quirks & USB_QUIRK_FORCE_ONE_CONFIG) {
 931		dev_info(ddev, "Device claims zero configurations, forcing to 1\n");
 932		dev->descriptor.bNumConfigurations = 1;
 933		ncfg = 1;
 934	} else if (ncfg < 1) {
 935		dev_err(ddev, "no configurations\n");
 936		return -EINVAL;
 937	}
 938
 939	length = ncfg * sizeof(struct usb_host_config);
 940	dev->config = kzalloc(length, GFP_KERNEL);
 941	if (!dev->config)
 942		return -ENOMEM;
 943
 944	length = ncfg * sizeof(char *);
 945	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 946	if (!dev->rawdescriptors)
 947		return -ENOMEM;
 948
 949	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 950	if (!desc)
 951		return -ENOMEM;
 952
 953	for (cfgno = 0; cfgno < ncfg; cfgno++) {
 954		/* We grab just the first descriptor so we know how long
 955		 * the whole configuration is */
 956		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 957		    desc, USB_DT_CONFIG_SIZE);
 958		if (result < 0) {
 959			dev_err(ddev, "unable to read config index %d "
 960			    "descriptor/%s: %d\n", cfgno, "start", result);
 961			if (result != -EPIPE)
 962				goto err;
 963			dev_notice(ddev, "chopping to %d config(s)\n", cfgno);
 964			dev->descriptor.bNumConfigurations = cfgno;
 965			break;
 966		} else if (result < 4) {
 967			dev_err(ddev, "config index %d descriptor too short "
 968			    "(expected %i, got %i)\n", cfgno,
 969			    USB_DT_CONFIG_SIZE, result);
 970			result = -EINVAL;
 971			goto err;
 972		}
 973		length = max_t(int, le16_to_cpu(desc->wTotalLength),
 974		    USB_DT_CONFIG_SIZE);
 975
 976		/* Now that we know the length, get the whole thing */
 977		bigbuffer = kmalloc(length, GFP_KERNEL);
 978		if (!bigbuffer) {
 979			result = -ENOMEM;
 980			goto err;
 981		}
 982
 983		if (dev->quirks & USB_QUIRK_DELAY_INIT)
 984			msleep(200);
 985
 986		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 987		    bigbuffer, length);
 988		if (result < 0) {
 989			dev_err(ddev, "unable to read config index %d "
 990			    "descriptor/%s\n", cfgno, "all");
 991			kfree(bigbuffer);
 992			goto err;
 993		}
 994		if (result < length) {
 995			dev_notice(ddev, "config index %d descriptor too short "
 996			    "(expected %i, got %i)\n", cfgno, length, result);
 997			length = result;
 998		}
 999
1000		dev->rawdescriptors[cfgno] = bigbuffer;
1001
1002		result = usb_parse_configuration(dev, cfgno,
1003		    &dev->config[cfgno], bigbuffer, length);
1004		if (result < 0) {
1005			++cfgno;
1006			goto err;
1007		}
1008	}
1009
1010err:
1011	kfree(desc);
1012	dev->descriptor.bNumConfigurations = cfgno;
1013
1014	return result;
1015}
1016
1017void usb_release_bos_descriptor(struct usb_device *dev)
1018{
1019	if (dev->bos) {
1020		kfree(dev->bos->desc);
1021		kfree(dev->bos);
1022		dev->bos = NULL;
1023	}
1024}
1025
1026static const __u8 bos_desc_len[256] = {
1027	[USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
1028	[USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
1029	[USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
1030	[USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
1031	[CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
1032	[USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
1033};
1034
1035/* Get BOS descriptor set */
1036int usb_get_bos_descriptor(struct usb_device *dev)
1037{
1038	struct device *ddev = &dev->dev;
1039	struct usb_bos_descriptor *bos;
1040	struct usb_dev_cap_header *cap;
1041	struct usb_ssp_cap_descriptor *ssp_cap;
1042	unsigned char *buffer, *buffer0;
1043	int length, total_len, num, i, ssac;
1044	__u8 cap_type;
1045	int ret;
1046
1047	if (dev->quirks & USB_QUIRK_NO_BOS) {
1048		dev_dbg(ddev, "skipping BOS descriptor\n");
1049		return -ENOMSG;
1050	}
1051
1052	bos = kzalloc(sizeof(*bos), GFP_KERNEL);
1053	if (!bos)
1054		return -ENOMEM;
1055
1056	/* Get BOS descriptor */
1057	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
1058	if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) {
1059		dev_notice(ddev, "unable to get BOS descriptor or descriptor too short\n");
1060		if (ret >= 0)
1061			ret = -ENOMSG;
1062		kfree(bos);
1063		return ret;
1064	}
1065
1066	length = bos->bLength;
1067	total_len = le16_to_cpu(bos->wTotalLength);
1068	num = bos->bNumDeviceCaps;
1069	kfree(bos);
1070	if (total_len < length)
1071		return -EINVAL;
1072
1073	dev->bos = kzalloc(sizeof(*dev->bos), GFP_KERNEL);
1074	if (!dev->bos)
1075		return -ENOMEM;
1076
1077	/* Now let's get the whole BOS descriptor set */
1078	buffer = kzalloc(total_len, GFP_KERNEL);
1079	if (!buffer) {
1080		ret = -ENOMEM;
1081		goto err;
1082	}
1083	dev->bos->desc = (struct usb_bos_descriptor *)buffer;
1084
1085	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
1086	if (ret < total_len) {
1087		dev_notice(ddev, "unable to get BOS descriptor set\n");
1088		if (ret >= 0)
1089			ret = -ENOMSG;
1090		goto err;
1091	}
1092
1093	buffer0 = buffer;
1094	total_len -= length;
1095	buffer += length;
1096
1097	for (i = 0; i < num; i++) {
1098		cap = (struct usb_dev_cap_header *)buffer;
1099
1100		if (total_len < sizeof(*cap) || total_len < cap->bLength) {
1101			dev->bos->desc->bNumDeviceCaps = i;
1102			break;
1103		}
1104		cap_type = cap->bDevCapabilityType;
1105		length = cap->bLength;
1106		if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
1107			dev->bos->desc->bNumDeviceCaps = i;
1108			break;
1109		}
1110
1111		if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
1112			dev_notice(ddev, "descriptor type invalid, skip\n");
1113			goto skip_to_next_descriptor;
1114		}
1115
1116		switch (cap_type) {
1117		case USB_CAP_TYPE_EXT:
1118			dev->bos->ext_cap =
1119				(struct usb_ext_cap_descriptor *)buffer;
1120			break;
1121		case USB_SS_CAP_TYPE:
1122			dev->bos->ss_cap =
1123				(struct usb_ss_cap_descriptor *)buffer;
1124			break;
1125		case USB_SSP_CAP_TYPE:
1126			ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
1127			ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
1128				USB_SSP_SUBLINK_SPEED_ATTRIBS);
1129			if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
1130				dev->bos->ssp_cap = ssp_cap;
1131			break;
1132		case CONTAINER_ID_TYPE:
1133			dev->bos->ss_id =
1134				(struct usb_ss_container_id_descriptor *)buffer;
1135			break;
1136		case USB_PTM_CAP_TYPE:
1137			dev->bos->ptm_cap =
1138				(struct usb_ptm_cap_descriptor *)buffer;
1139			break;
1140		default:
1141			break;
1142		}
1143
1144skip_to_next_descriptor:
1145		total_len -= length;
1146		buffer += length;
1147	}
1148	dev->bos->desc->wTotalLength = cpu_to_le16(buffer - buffer0);
1149
1150	return 0;
1151
1152err:
1153	usb_release_bos_descriptor(dev);
1154	return ret;
1155}