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
  22static inline const char *plural(int n)
  23{
  24	return (n == 1 ? "" : "s");
  25}
  26
  27static 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
  51static 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_notice(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
  72static 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_notice(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_notice(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_notice(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_notice(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_notice(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_notice(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_notice(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
 179static 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};
 185static 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};
 191static 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};
 199static 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
 206static 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 */
 224static 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
 254static 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_notice(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_notice(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_notice(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 some endpoints */
 302	if (udev->quirks & USB_QUIRK_ENDPOINT_IGNORE) {
 303		if (usb_endpoint_is_ignored(udev, ifp, d)) {
 304			dev_notice(ddev, "config %d interface %d altsetting %d has an ignored 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 (udev->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 (udev->quirks & USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 347				n = clamp(fls(d->bInterval) + 3, i, j);
 348				i = j = n;
 349			}
 350			/*
 351			 * This quirk fixes bIntervals reported in
 352			 * linear microframes.
 353			 */
 354			if (udev->quirks & USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 355				n = clamp(fls(d->bInterval), i, j);
 356				i = j = n;
 357			}
 358			break;
 359		default:		/* USB_SPEED_FULL or _LOW */
 360			/*
 361			 * For low-speed, 10 ms is the official minimum.
 362			 * But some "overclocked" devices might want faster
 363			 * polling so we'll allow it.
 364			 */
 365			n = 10;
 366			break;
 367		}
 368	} else if (usb_endpoint_xfer_isoc(d)) {
 369		i = 1;
 370		j = 16;
 371		switch (udev->speed) {
 372		case USB_SPEED_HIGH:
 373			n = 7;		/* 8 ms = 2^(7-1) uframes */
 374			break;
 375		default:		/* USB_SPEED_FULL */
 376			n = 4;		/* 8 ms = 2^(4-1) frames */
 377			break;
 378		}
 379	}
 380	if (d->bInterval < i || d->bInterval > j) {
 381		dev_notice(ddev, "config %d interface %d altsetting %d "
 382		    "endpoint 0x%X has an invalid bInterval %d, "
 383		    "changing to %d\n",
 384		    cfgno, inum, asnum,
 385		    d->bEndpointAddress, d->bInterval, n);
 386		endpoint->desc.bInterval = n;
 387	}
 388
 389	/* Some buggy low-speed devices have Bulk endpoints, which is
 390	 * explicitly forbidden by the USB spec.  In an attempt to make
 391	 * them usable, we will try treating them as Interrupt endpoints.
 392	 */
 393	if (udev->speed == USB_SPEED_LOW && usb_endpoint_xfer_bulk(d)) {
 394		dev_notice(ddev, "config %d interface %d altsetting %d "
 395		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
 396		    cfgno, inum, asnum, d->bEndpointAddress);
 397		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
 398		endpoint->desc.bInterval = 1;
 399		if (usb_endpoint_maxp(&endpoint->desc) > 8)
 400			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 401	}
 402
 403	/*
 404	 * Validate the wMaxPacketSize field.
 405	 * Some devices have isochronous endpoints in altsetting 0;
 406	 * the USB-2 spec requires such endpoints to have wMaxPacketSize = 0
 407	 * (see the end of section 5.6.3), so don't warn about them.
 408	 */
 409	maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize);
 410	if (maxp == 0 && !(usb_endpoint_xfer_isoc(d) && asnum == 0)) {
 411		dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
 412		    cfgno, inum, asnum, d->bEndpointAddress);
 413	}
 414
 415	/* Find the highest legal maxpacket size for this endpoint */
 416	i = 0;		/* additional transactions per microframe */
 417	switch (udev->speed) {
 418	case USB_SPEED_LOW:
 419		maxpacket_maxes = low_speed_maxpacket_maxes;
 420		break;
 421	case USB_SPEED_FULL:
 422		maxpacket_maxes = full_speed_maxpacket_maxes;
 423		break;
 424	case USB_SPEED_HIGH:
 425		/* Multiple-transactions bits are allowed only for HS periodic endpoints */
 426		if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
 427			i = maxp & USB_EP_MAXP_MULT_MASK;
 428			maxp &= ~i;
 429		}
 430		fallthrough;
 431	default:
 432		maxpacket_maxes = high_speed_maxpacket_maxes;
 433		break;
 434	case USB_SPEED_SUPER:
 435	case USB_SPEED_SUPER_PLUS:
 436		maxpacket_maxes = super_speed_maxpacket_maxes;
 437		break;
 438	}
 439	j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
 440
 441	if (maxp > j) {
 442		dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
 443		    cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
 444		maxp = j;
 445		endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
 446	}
 447
 448	/*
 449	 * Some buggy high speed devices have bulk endpoints using
 450	 * maxpacket sizes other than 512.  High speed HCDs may not
 451	 * be able to handle that particular bug, so let's warn...
 452	 */
 453	if (udev->speed == USB_SPEED_HIGH && usb_endpoint_xfer_bulk(d)) {
 454		if (maxp != 512)
 455			dev_notice(ddev, "config %d interface %d altsetting %d "
 456				"bulk endpoint 0x%X has invalid maxpacket %d\n",
 457				cfgno, inum, asnum, d->bEndpointAddress,
 458				maxp);
 459	}
 460
 461	/* Parse a possible SuperSpeed endpoint companion descriptor */
 462	if (udev->speed >= USB_SPEED_SUPER)
 463		usb_parse_ss_endpoint_companion(ddev, cfgno,
 464				inum, asnum, endpoint, buffer, size);
 465
 466	/* Skip over any Class Specific or Vendor Specific descriptors;
 467	 * find the next endpoint or interface descriptor */
 468	endpoint->extra = buffer;
 469	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 470			USB_DT_INTERFACE, &n);
 471	endpoint->extralen = i;
 472	retval = buffer - buffer0 + i;
 473	if (n > 0)
 474		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 475		    n, plural(n), "endpoint");
 476	return retval;
 477
 478skip_to_next_endpoint_or_interface_descriptor:
 479	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 480	    USB_DT_INTERFACE, NULL);
 481	return buffer - buffer0 + i;
 482}
 483
 484void usb_release_interface_cache(struct kref *ref)
 485{
 486	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
 487	int j;
 488
 489	for (j = 0; j < intfc->num_altsetting; j++) {
 490		struct usb_host_interface *alt = &intfc->altsetting[j];
 491
 492		kfree(alt->endpoint);
 493		kfree(alt->string);
 494	}
 495	kfree(intfc);
 496}
 497
 498static int usb_parse_interface(struct device *ddev, int cfgno,
 499    struct usb_host_config *config, unsigned char *buffer, int size,
 500    u8 inums[], u8 nalts[])
 501{
 502	unsigned char *buffer0 = buffer;
 503	struct usb_interface_descriptor	*d;
 504	int inum, asnum;
 505	struct usb_interface_cache *intfc;
 506	struct usb_host_interface *alt;
 507	int i, n;
 508	int len, retval;
 509	int num_ep, num_ep_orig;
 510
 511	d = (struct usb_interface_descriptor *) buffer;
 512	buffer += d->bLength;
 513	size -= d->bLength;
 514
 515	if (d->bLength < USB_DT_INTERFACE_SIZE)
 516		goto skip_to_next_interface_descriptor;
 517
 518	/* Which interface entry is this? */
 519	intfc = NULL;
 520	inum = d->bInterfaceNumber;
 521	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
 522		if (inums[i] == inum) {
 523			intfc = config->intf_cache[i];
 524			break;
 525		}
 526	}
 527	if (!intfc || intfc->num_altsetting >= nalts[i])
 528		goto skip_to_next_interface_descriptor;
 529
 530	/* Check for duplicate altsetting entries */
 531	asnum = d->bAlternateSetting;
 532	for ((i = 0, alt = &intfc->altsetting[0]);
 533	      i < intfc->num_altsetting;
 534	     (++i, ++alt)) {
 535		if (alt->desc.bAlternateSetting == asnum) {
 536			dev_notice(ddev, "Duplicate descriptor for config %d "
 537			    "interface %d altsetting %d, skipping\n",
 538			    cfgno, inum, asnum);
 539			goto skip_to_next_interface_descriptor;
 540		}
 541	}
 542
 543	++intfc->num_altsetting;
 544	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
 545
 546	/* Skip over any Class Specific or Vendor Specific descriptors;
 547	 * find the first endpoint or interface descriptor */
 548	alt->extra = buffer;
 549	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
 550	    USB_DT_INTERFACE, &n);
 551	alt->extralen = i;
 552	if (n > 0)
 553		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 554		    n, plural(n), "interface");
 555	buffer += i;
 556	size -= i;
 557
 558	/* Allocate space for the right(?) number of endpoints */
 559	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
 560	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
 561	if (num_ep > USB_MAXENDPOINTS) {
 562		dev_notice(ddev, "too many endpoints for config %d interface %d "
 563		    "altsetting %d: %d, using maximum allowed: %d\n",
 564		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
 565		num_ep = USB_MAXENDPOINTS;
 566	}
 567
 568	if (num_ep > 0) {
 569		/* Can't allocate 0 bytes */
 570		len = sizeof(struct usb_host_endpoint) * num_ep;
 571		alt->endpoint = kzalloc(len, GFP_KERNEL);
 572		if (!alt->endpoint)
 573			return -ENOMEM;
 574	}
 575
 576	/* Parse all the endpoint descriptors */
 577	n = 0;
 578	while (size > 0) {
 579		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 580		     == USB_DT_INTERFACE)
 581			break;
 582		retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
 583				alt, num_ep, buffer, size);
 584		if (retval < 0)
 585			return retval;
 586		++n;
 587
 588		buffer += retval;
 589		size -= retval;
 590	}
 591
 592	if (n != num_ep_orig)
 593		dev_notice(ddev, "config %d interface %d altsetting %d has %d "
 594		    "endpoint descriptor%s, different from the interface "
 595		    "descriptor's value: %d\n",
 596		    cfgno, inum, asnum, n, plural(n), num_ep_orig);
 597	return buffer - buffer0;
 598
 599skip_to_next_interface_descriptor:
 600	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 601	    USB_DT_INTERFACE, NULL);
 602	return buffer - buffer0 + i;
 603}
 604
 605static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
 606    struct usb_host_config *config, unsigned char *buffer, int size)
 607{
 608	struct device *ddev = &dev->dev;
 609	unsigned char *buffer0 = buffer;
 610	int cfgno;
 611	int nintf, nintf_orig;
 612	int i, j, n;
 613	struct usb_interface_cache *intfc;
 614	unsigned char *buffer2;
 615	int size2;
 616	struct usb_descriptor_header *header;
 617	int retval;
 618	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
 619	unsigned iad_num = 0;
 620
 621	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
 622	nintf = nintf_orig = config->desc.bNumInterfaces;
 623	config->desc.bNumInterfaces = 0;	// Adjusted later
 624
 625	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
 626	    config->desc.bLength < USB_DT_CONFIG_SIZE ||
 627	    config->desc.bLength > size) {
 628		dev_notice(ddev, "invalid descriptor for config index %d: "
 629		    "type = 0x%X, length = %d\n", cfgidx,
 630		    config->desc.bDescriptorType, config->desc.bLength);
 631		return -EINVAL;
 632	}
 633	cfgno = config->desc.bConfigurationValue;
 634
 635	buffer += config->desc.bLength;
 636	size -= config->desc.bLength;
 637
 638	if (nintf > USB_MAXINTERFACES) {
 639		dev_notice(ddev, "config %d has too many interfaces: %d, "
 640		    "using maximum allowed: %d\n",
 641		    cfgno, nintf, USB_MAXINTERFACES);
 642		nintf = USB_MAXINTERFACES;
 643	}
 644
 645	/* Go through the descriptors, checking their length and counting the
 646	 * number of altsettings for each interface */
 647	n = 0;
 648	for ((buffer2 = buffer, size2 = size);
 649	      size2 > 0;
 650	     (buffer2 += header->bLength, size2 -= header->bLength)) {
 651
 652		if (size2 < sizeof(struct usb_descriptor_header)) {
 653			dev_notice(ddev, "config %d descriptor has %d excess "
 654			    "byte%s, ignoring\n",
 655			    cfgno, size2, plural(size2));
 656			break;
 657		}
 658
 659		header = (struct usb_descriptor_header *) buffer2;
 660		if ((header->bLength > size2) || (header->bLength < 2)) {
 661			dev_notice(ddev, "config %d has an invalid descriptor "
 662			    "of length %d, skipping remainder of the config\n",
 663			    cfgno, header->bLength);
 664			break;
 665		}
 666
 667		if (header->bDescriptorType == USB_DT_INTERFACE) {
 668			struct usb_interface_descriptor *d;
 669			int inum;
 670
 671			d = (struct usb_interface_descriptor *) header;
 672			if (d->bLength < USB_DT_INTERFACE_SIZE) {
 673				dev_notice(ddev, "config %d has an invalid "
 674				    "interface descriptor of length %d, "
 675				    "skipping\n", cfgno, d->bLength);
 676				continue;
 677			}
 678
 679			inum = d->bInterfaceNumber;
 680
 681			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
 682			    n >= nintf_orig) {
 683				dev_notice(ddev, "config %d has more interface "
 684				    "descriptors, than it declares in "
 685				    "bNumInterfaces, ignoring interface "
 686				    "number: %d\n", cfgno, inum);
 687				continue;
 688			}
 689
 690			if (inum >= nintf_orig)
 691				dev_notice(ddev, "config %d has an invalid "
 692				    "interface number: %d but max is %d\n",
 693				    cfgno, inum, nintf_orig - 1);
 694
 695			/* Have we already encountered this interface?
 696			 * Count its altsettings */
 697			for (i = 0; i < n; ++i) {
 698				if (inums[i] == inum)
 699					break;
 700			}
 701			if (i < n) {
 702				if (nalts[i] < 255)
 703					++nalts[i];
 704			} else if (n < USB_MAXINTERFACES) {
 705				inums[n] = inum;
 706				nalts[n] = 1;
 707				++n;
 708			}
 709
 710		} else if (header->bDescriptorType ==
 711				USB_DT_INTERFACE_ASSOCIATION) {
 712			struct usb_interface_assoc_descriptor *d;
 713
 714			d = (struct usb_interface_assoc_descriptor *)header;
 715			if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
 716				dev_notice(ddev,
 717					 "config %d has an invalid interface association descriptor of length %d, skipping\n",
 718					 cfgno, d->bLength);
 719				continue;
 720			}
 721
 722			if (iad_num == USB_MAXIADS) {
 723				dev_notice(ddev, "found more Interface "
 724					       "Association Descriptors "
 725					       "than allocated for in "
 726					       "configuration %d\n", cfgno);
 727			} else {
 728				config->intf_assoc[iad_num] = d;
 729				iad_num++;
 730			}
 731
 732		} else if (header->bDescriptorType == USB_DT_DEVICE ||
 733			    header->bDescriptorType == USB_DT_CONFIG)
 734			dev_notice(ddev, "config %d contains an unexpected "
 735			    "descriptor of type 0x%X, skipping\n",
 736			    cfgno, header->bDescriptorType);
 737
 738	}	/* for ((buffer2 = buffer, size2 = size); ...) */
 739	size = buffer2 - buffer;
 740	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
 741
 742	if (n != nintf)
 743		dev_notice(ddev, "config %d has %d interface%s, different from "
 744		    "the descriptor's value: %d\n",
 745		    cfgno, n, plural(n), nintf_orig);
 746	else if (n == 0)
 747		dev_notice(ddev, "config %d has no interfaces?\n", cfgno);
 748	config->desc.bNumInterfaces = nintf = n;
 749
 750	/* Check for missing interface numbers */
 751	for (i = 0; i < nintf; ++i) {
 752		for (j = 0; j < nintf; ++j) {
 753			if (inums[j] == i)
 754				break;
 755		}
 756		if (j >= nintf)
 757			dev_notice(ddev, "config %d has no interface number "
 758			    "%d\n", cfgno, i);
 759	}
 760
 761	/* Allocate the usb_interface_caches and altsetting arrays */
 762	for (i = 0; i < nintf; ++i) {
 763		j = nalts[i];
 764		if (j > USB_MAXALTSETTING) {
 765			dev_notice(ddev, "too many alternate settings for "
 766			    "config %d interface %d: %d, "
 767			    "using maximum allowed: %d\n",
 768			    cfgno, inums[i], j, USB_MAXALTSETTING);
 769			nalts[i] = j = USB_MAXALTSETTING;
 770		}
 771
 772		intfc = kzalloc(struct_size(intfc, altsetting, j), GFP_KERNEL);
 773		config->intf_cache[i] = intfc;
 774		if (!intfc)
 775			return -ENOMEM;
 776		kref_init(&intfc->ref);
 777	}
 778
 779	/* FIXME: parse the BOS descriptor */
 780
 781	/* Skip over any Class Specific or Vendor Specific descriptors;
 782	 * find the first interface descriptor */
 783	config->extra = buffer;
 784	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
 785	    USB_DT_INTERFACE, &n);
 786	config->extralen = i;
 787	if (n > 0)
 788		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
 789		    n, plural(n), "configuration");
 790	buffer += i;
 791	size -= i;
 792
 793	/* Parse all the interface/altsetting descriptors */
 794	while (size > 0) {
 795		retval = usb_parse_interface(ddev, cfgno, config,
 796		    buffer, size, inums, nalts);
 797		if (retval < 0)
 798			return retval;
 799
 800		buffer += retval;
 801		size -= retval;
 802	}
 803
 804	/* Check for missing altsettings */
 805	for (i = 0; i < nintf; ++i) {
 806		intfc = config->intf_cache[i];
 807		for (j = 0; j < intfc->num_altsetting; ++j) {
 808			for (n = 0; n < intfc->num_altsetting; ++n) {
 809				if (intfc->altsetting[n].desc.
 810				    bAlternateSetting == j)
 811					break;
 812			}
 813			if (n >= intfc->num_altsetting)
 814				dev_notice(ddev, "config %d interface %d has no "
 815				    "altsetting %d\n", cfgno, inums[i], j);
 816		}
 817	}
 818
 819	return 0;
 820}
 821
 822/* hub-only!! ... and only exported for reset/reinit path.
 823 * otherwise used internally on disconnect/destroy path
 824 */
 825void usb_destroy_configuration(struct usb_device *dev)
 826{
 827	int c, i;
 828
 829	if (!dev->config)
 830		return;
 831
 832	if (dev->rawdescriptors) {
 833		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
 834			kfree(dev->rawdescriptors[i]);
 835
 836		kfree(dev->rawdescriptors);
 837		dev->rawdescriptors = NULL;
 838	}
 839
 840	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
 841		struct usb_host_config *cf = &dev->config[c];
 842
 843		kfree(cf->string);
 844		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
 845			if (cf->intf_cache[i])
 846				kref_put(&cf->intf_cache[i]->ref,
 847					  usb_release_interface_cache);
 848		}
 849	}
 850	kfree(dev->config);
 851	dev->config = NULL;
 852}
 853
 854
 855/*
 856 * Get the USB config descriptors, cache and parse'em
 857 *
 858 * hub-only!! ... and only in reset path, or usb_new_device()
 859 * (used by real hubs and virtual root hubs)
 860 */
 861int usb_get_configuration(struct usb_device *dev)
 862{
 863	struct device *ddev = &dev->dev;
 864	int ncfg = dev->descriptor.bNumConfigurations;
 865	unsigned int cfgno, length;
 866	unsigned char *bigbuffer;
 867	struct usb_config_descriptor *desc;
 868	int result;
 869
 870	if (ncfg > USB_MAXCONFIG) {
 871		dev_notice(ddev, "too many configurations: %d, "
 872		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
 873		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
 874	}
 875
 876	if (ncfg < 1) {
 877		dev_err(ddev, "no configurations\n");
 878		return -EINVAL;
 879	}
 880
 881	length = ncfg * sizeof(struct usb_host_config);
 882	dev->config = kzalloc(length, GFP_KERNEL);
 883	if (!dev->config)
 884		return -ENOMEM;
 885
 886	length = ncfg * sizeof(char *);
 887	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
 888	if (!dev->rawdescriptors)
 889		return -ENOMEM;
 890
 891	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
 892	if (!desc)
 893		return -ENOMEM;
 894
 895	for (cfgno = 0; cfgno < ncfg; cfgno++) {
 896		/* We grab just the first descriptor so we know how long
 897		 * the whole configuration is */
 898		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 899		    desc, USB_DT_CONFIG_SIZE);
 900		if (result < 0) {
 901			dev_err(ddev, "unable to read config index %d "
 902			    "descriptor/%s: %d\n", cfgno, "start", result);
 903			if (result != -EPIPE)
 904				goto err;
 905			dev_notice(ddev, "chopping to %d config(s)\n", cfgno);
 906			dev->descriptor.bNumConfigurations = cfgno;
 907			break;
 908		} else if (result < 4) {
 909			dev_err(ddev, "config index %d descriptor too short "
 910			    "(expected %i, got %i)\n", cfgno,
 911			    USB_DT_CONFIG_SIZE, result);
 912			result = -EINVAL;
 913			goto err;
 914		}
 915		length = max((int) le16_to_cpu(desc->wTotalLength),
 916		    USB_DT_CONFIG_SIZE);
 917
 918		/* Now that we know the length, get the whole thing */
 919		bigbuffer = kmalloc(length, GFP_KERNEL);
 920		if (!bigbuffer) {
 921			result = -ENOMEM;
 922			goto err;
 923		}
 924
 925		if (dev->quirks & USB_QUIRK_DELAY_INIT)
 926			msleep(200);
 927
 928		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 929		    bigbuffer, length);
 930		if (result < 0) {
 931			dev_err(ddev, "unable to read config index %d "
 932			    "descriptor/%s\n", cfgno, "all");
 933			kfree(bigbuffer);
 934			goto err;
 935		}
 936		if (result < length) {
 937			dev_notice(ddev, "config index %d descriptor too short "
 938			    "(expected %i, got %i)\n", cfgno, length, result);
 939			length = result;
 940		}
 941
 942		dev->rawdescriptors[cfgno] = bigbuffer;
 943
 944		result = usb_parse_configuration(dev, cfgno,
 945		    &dev->config[cfgno], bigbuffer, length);
 946		if (result < 0) {
 947			++cfgno;
 948			goto err;
 949		}
 950	}
 951
 952err:
 953	kfree(desc);
 954	dev->descriptor.bNumConfigurations = cfgno;
 955
 956	return result;
 957}
 958
 959void usb_release_bos_descriptor(struct usb_device *dev)
 960{
 961	if (dev->bos) {
 962		kfree(dev->bos->desc);
 963		kfree(dev->bos);
 964		dev->bos = NULL;
 965	}
 966}
 967
 968static const __u8 bos_desc_len[256] = {
 969	[USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
 970	[USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
 971	[USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
 972	[USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
 973	[CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
 974	[USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
 975};
 976
 977/* Get BOS descriptor set */
 978int usb_get_bos_descriptor(struct usb_device *dev)
 979{
 980	struct device *ddev = &dev->dev;
 981	struct usb_bos_descriptor *bos;
 982	struct usb_dev_cap_header *cap;
 983	struct usb_ssp_cap_descriptor *ssp_cap;
 984	unsigned char *buffer, *buffer0;
 985	int length, total_len, num, i, ssac;
 986	__u8 cap_type;
 987	int ret;
 988
 989	bos = kzalloc(sizeof(*bos), GFP_KERNEL);
 990	if (!bos)
 991		return -ENOMEM;
 992
 993	/* Get BOS descriptor */
 994	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
 995	if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) {
 996		dev_notice(ddev, "unable to get BOS descriptor or descriptor too short\n");
 997		if (ret >= 0)
 998			ret = -ENOMSG;
 999		kfree(bos);
1000		return ret;
1001	}
1002
1003	length = bos->bLength;
1004	total_len = le16_to_cpu(bos->wTotalLength);
1005	num = bos->bNumDeviceCaps;
1006	kfree(bos);
1007	if (total_len < length)
1008		return -EINVAL;
1009
1010	dev->bos = kzalloc(sizeof(*dev->bos), GFP_KERNEL);
1011	if (!dev->bos)
1012		return -ENOMEM;
1013
1014	/* Now let's get the whole BOS descriptor set */
1015	buffer = kzalloc(total_len, GFP_KERNEL);
1016	if (!buffer) {
1017		ret = -ENOMEM;
1018		goto err;
1019	}
1020	dev->bos->desc = (struct usb_bos_descriptor *)buffer;
1021
1022	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
1023	if (ret < total_len) {
1024		dev_notice(ddev, "unable to get BOS descriptor set\n");
1025		if (ret >= 0)
1026			ret = -ENOMSG;
1027		goto err;
1028	}
1029
1030	buffer0 = buffer;
1031	total_len -= length;
1032	buffer += length;
1033
1034	for (i = 0; i < num; i++) {
1035		cap = (struct usb_dev_cap_header *)buffer;
1036
1037		if (total_len < sizeof(*cap) || total_len < cap->bLength) {
1038			dev->bos->desc->bNumDeviceCaps = i;
1039			break;
1040		}
1041		cap_type = cap->bDevCapabilityType;
1042		length = cap->bLength;
1043		if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
1044			dev->bos->desc->bNumDeviceCaps = i;
1045			break;
1046		}
1047
1048		if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
1049			dev_notice(ddev, "descriptor type invalid, skip\n");
1050			goto skip_to_next_descriptor;
1051		}
1052
1053		switch (cap_type) {
 
 
 
1054		case USB_CAP_TYPE_EXT:
1055			dev->bos->ext_cap =
1056				(struct usb_ext_cap_descriptor *)buffer;
1057			break;
1058		case USB_SS_CAP_TYPE:
1059			dev->bos->ss_cap =
1060				(struct usb_ss_cap_descriptor *)buffer;
1061			break;
1062		case USB_SSP_CAP_TYPE:
1063			ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
1064			ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
1065				USB_SSP_SUBLINK_SPEED_ATTRIBS);
1066			if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
1067				dev->bos->ssp_cap = ssp_cap;
1068			break;
1069		case CONTAINER_ID_TYPE:
1070			dev->bos->ss_id =
1071				(struct usb_ss_container_id_descriptor *)buffer;
1072			break;
1073		case USB_PTM_CAP_TYPE:
1074			dev->bos->ptm_cap =
1075				(struct usb_ptm_cap_descriptor *)buffer;
1076			break;
1077		default:
1078			break;
1079		}
1080
1081skip_to_next_descriptor:
1082		total_len -= length;
1083		buffer += length;
1084	}
1085	dev->bos->desc->wTotalLength = cpu_to_le16(buffer - buffer0);
1086
1087	return 0;
1088
1089err:
1090	usb_release_bos_descriptor(dev);
1091	return ret;
1092}