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v3.1
  1#include <linux/usb.h>
  2#include <linux/usb/ch9.h>
  3#include <linux/usb/hcd.h>
  4#include <linux/usb/quirks.h>
  5#include <linux/module.h>
  6#include <linux/init.h>
  7#include <linux/slab.h>
  8#include <linux/device.h>
  9#include <asm/byteorder.h>
 10#include "usb.h"
 11
 12
 13#define USB_MAXALTSETTING		128	/* Hard limit */
 14#define USB_MAXENDPOINTS		30	/* Hard limit */
 15
 16#define USB_MAXCONFIG			8	/* Arbitrary limit */
 17
 18
 19static inline const char *plural(int n)
 20{
 21	return (n == 1 ? "" : "s");
 22}
 23
 24static int find_next_descriptor(unsigned char *buffer, int size,
 25    int dt1, int dt2, int *num_skipped)
 26{
 27	struct usb_descriptor_header *h;
 28	int n = 0;
 29	unsigned char *buffer0 = buffer;
 30
 31	/* Find the next descriptor of type dt1 or dt2 */
 32	while (size > 0) {
 33		h = (struct usb_descriptor_header *) buffer;
 34		if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
 35			break;
 36		buffer += h->bLength;
 37		size -= h->bLength;
 38		++n;
 39	}
 40
 41	/* Store the number of descriptors skipped and return the
 42	 * number of bytes skipped */
 43	if (num_skipped)
 44		*num_skipped = n;
 45	return buffer - buffer0;
 46}
 47
 48static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
 49		int inum, int asnum, struct usb_host_endpoint *ep,
 50		unsigned char *buffer, int size)
 51{
 52	struct usb_ss_ep_comp_descriptor *desc;
 53	int max_tx;
 54
 55	/* The SuperSpeed endpoint companion descriptor is supposed to
 56	 * be the first thing immediately following the endpoint descriptor.
 57	 */
 58	desc = (struct usb_ss_ep_comp_descriptor *) buffer;
 59	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
 60			size < USB_DT_SS_EP_COMP_SIZE) {
 61		dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
 62				" interface %d altsetting %d ep %d: "
 63				"using minimum values\n",
 64				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 65
 66		/* Fill in some default values.
 67		 * Leave bmAttributes as zero, which will mean no streams for
 68		 * bulk, and isoc won't support multiple bursts of packets.
 69		 * With bursts of only one packet, and a Mult of 1, the max
 70		 * amount of data moved per endpoint service interval is one
 71		 * packet.
 72		 */
 73		ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
 74		ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
 75		if (usb_endpoint_xfer_isoc(&ep->desc) ||
 76				usb_endpoint_xfer_int(&ep->desc))
 77			ep->ss_ep_comp.wBytesPerInterval =
 78					ep->desc.wMaxPacketSize;
 79		return;
 80	}
 81
 82	memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 83
 84	/* Check the various values */
 85	if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 86		dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
 87				"config %d interface %d altsetting %d ep %d: "
 88				"setting to zero\n", desc->bMaxBurst,
 89				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 90		ep->ss_ep_comp.bMaxBurst = 0;
 91	} else if (desc->bMaxBurst > 15) {
 92		dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
 93				"config %d interface %d altsetting %d ep %d: "
 94				"setting to 15\n", desc->bMaxBurst,
 95				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 96		ep->ss_ep_comp.bMaxBurst = 15;
 97	}
 98
 99	if ((usb_endpoint_xfer_control(&ep->desc) ||
100			usb_endpoint_xfer_int(&ep->desc)) &&
101				desc->bmAttributes != 0) {
102		dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
103				"config %d interface %d altsetting %d ep %d: "
104				"setting to zero\n",
105				usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
106				desc->bmAttributes,
107				cfgno, inum, asnum, ep->desc.bEndpointAddress);
108		ep->ss_ep_comp.bmAttributes = 0;
109	} else if (usb_endpoint_xfer_bulk(&ep->desc) &&
110			desc->bmAttributes > 16) {
111		dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
112				"config %d interface %d altsetting %d ep %d: "
113				"setting to max\n",
114				cfgno, inum, asnum, ep->desc.bEndpointAddress);
115		ep->ss_ep_comp.bmAttributes = 16;
116	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&
117			desc->bmAttributes > 2) {
118		dev_warn(ddev, "Isoc endpoint has Mult of %d in "
119				"config %d interface %d altsetting %d ep %d: "
120				"setting to 3\n", desc->bmAttributes + 1,
121				cfgno, inum, asnum, ep->desc.bEndpointAddress);
122		ep->ss_ep_comp.bmAttributes = 2;
123	}
124
125	if (usb_endpoint_xfer_isoc(&ep->desc))
126		max_tx = (desc->bMaxBurst + 1) * (desc->bmAttributes + 1) *
127			le16_to_cpu(ep->desc.wMaxPacketSize);
128	else if (usb_endpoint_xfer_int(&ep->desc))
129		max_tx = le16_to_cpu(ep->desc.wMaxPacketSize) *
130			(desc->bMaxBurst + 1);
131	else
132		max_tx = 999999;
133	if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
134		dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
135				"config %d interface %d altsetting %d ep %d: "
136				"setting to %d\n",
137				usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
138				le16_to_cpu(desc->wBytesPerInterval),
139				cfgno, inum, asnum, ep->desc.bEndpointAddress,
140				max_tx);
141		ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
142	}
143}
144
145static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
146    int asnum, struct usb_host_interface *ifp, int num_ep,
147    unsigned char *buffer, int size)
148{
149	unsigned char *buffer0 = buffer;
150	struct usb_endpoint_descriptor *d;
151	struct usb_host_endpoint *endpoint;
152	int n, i, j, retval;
153
154	d = (struct usb_endpoint_descriptor *) buffer;
155	buffer += d->bLength;
156	size -= d->bLength;
157
158	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
159		n = USB_DT_ENDPOINT_AUDIO_SIZE;
160	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
161		n = USB_DT_ENDPOINT_SIZE;
162	else {
163		dev_warn(ddev, "config %d interface %d altsetting %d has an "
164		    "invalid endpoint descriptor of length %d, skipping\n",
165		    cfgno, inum, asnum, d->bLength);
166		goto skip_to_next_endpoint_or_interface_descriptor;
167	}
168
169	i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
170	if (i >= 16 || i == 0) {
171		dev_warn(ddev, "config %d interface %d altsetting %d has an "
172		    "invalid endpoint with address 0x%X, skipping\n",
173		    cfgno, inum, asnum, d->bEndpointAddress);
174		goto skip_to_next_endpoint_or_interface_descriptor;
175	}
176
177	/* Only store as many endpoints as we have room for */
178	if (ifp->desc.bNumEndpoints >= num_ep)
179		goto skip_to_next_endpoint_or_interface_descriptor;
180
181	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
182	++ifp->desc.bNumEndpoints;
183
184	memcpy(&endpoint->desc, d, n);
185	INIT_LIST_HEAD(&endpoint->urb_list);
186
187	/* Fix up bInterval values outside the legal range. Use 32 ms if no
188	 * proper value can be guessed. */
189	i = 0;		/* i = min, j = max, n = default */
190	j = 255;
191	if (usb_endpoint_xfer_int(d)) {
192		i = 1;
193		switch (to_usb_device(ddev)->speed) {
194		case USB_SPEED_SUPER:
195		case USB_SPEED_HIGH:
196			/* Many device manufacturers are using full-speed
197			 * bInterval values in high-speed interrupt endpoint
198			 * descriptors. Try to fix those and fall back to a
199			 * 32 ms default value otherwise. */
200			n = fls(d->bInterval*8);
201			if (n == 0)
202				n = 9;	/* 32 ms = 2^(9-1) uframes */
203			j = 16;
204			break;
205		default:		/* USB_SPEED_FULL or _LOW */
206			/* For low-speed, 10 ms is the official minimum.
207			 * But some "overclocked" devices might want faster
208			 * polling so we'll allow it. */
209			n = 32;
210			break;
211		}
212	} else if (usb_endpoint_xfer_isoc(d)) {
213		i = 1;
214		j = 16;
215		switch (to_usb_device(ddev)->speed) {
216		case USB_SPEED_HIGH:
217			n = 9;		/* 32 ms = 2^(9-1) uframes */
218			break;
219		default:		/* USB_SPEED_FULL */
220			n = 6;		/* 32 ms = 2^(6-1) frames */
221			break;
222		}
223	}
224	if (d->bInterval < i || d->bInterval > j) {
225		dev_warn(ddev, "config %d interface %d altsetting %d "
226		    "endpoint 0x%X has an invalid bInterval %d, "
227		    "changing to %d\n",
228		    cfgno, inum, asnum,
229		    d->bEndpointAddress, d->bInterval, n);
230		endpoint->desc.bInterval = n;
231	}
232
233	/* Some buggy low-speed devices have Bulk endpoints, which is
234	 * explicitly forbidden by the USB spec.  In an attempt to make
235	 * them usable, we will try treating them as Interrupt endpoints.
236	 */
237	if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
238			usb_endpoint_xfer_bulk(d)) {
239		dev_warn(ddev, "config %d interface %d altsetting %d "
240		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
241		    cfgno, inum, asnum, d->bEndpointAddress);
242		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
243		endpoint->desc.bInterval = 1;
244		if (le16_to_cpu(endpoint->desc.wMaxPacketSize) > 8)
245			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
246	}
247
248	/*
249	 * Some buggy high speed devices have bulk endpoints using
250	 * maxpacket sizes other than 512.  High speed HCDs may not
251	 * be able to handle that particular bug, so let's warn...
252	 */
253	if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
254			&& usb_endpoint_xfer_bulk(d)) {
255		unsigned maxp;
256
257		maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize) & 0x07ff;
258		if (maxp != 512)
259			dev_warn(ddev, "config %d interface %d altsetting %d "
260				"bulk endpoint 0x%X has invalid maxpacket %d\n",
261				cfgno, inum, asnum, d->bEndpointAddress,
262				maxp);
263	}
264
265	/* Parse a possible SuperSpeed endpoint companion descriptor */
266	if (to_usb_device(ddev)->speed == USB_SPEED_SUPER)
267		usb_parse_ss_endpoint_companion(ddev, cfgno,
268				inum, asnum, endpoint, buffer, size);
269
270	/* Skip over any Class Specific or Vendor Specific descriptors;
271	 * find the next endpoint or interface descriptor */
272	endpoint->extra = buffer;
273	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
274			USB_DT_INTERFACE, &n);
275	endpoint->extralen = i;
276	retval = buffer - buffer0 + i;
277	if (n > 0)
278		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
279		    n, plural(n), "endpoint");
280	return retval;
281
282skip_to_next_endpoint_or_interface_descriptor:
283	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
284	    USB_DT_INTERFACE, NULL);
285	return buffer - buffer0 + i;
286}
287
288void usb_release_interface_cache(struct kref *ref)
289{
290	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
291	int j;
292
293	for (j = 0; j < intfc->num_altsetting; j++) {
294		struct usb_host_interface *alt = &intfc->altsetting[j];
295
296		kfree(alt->endpoint);
297		kfree(alt->string);
298	}
299	kfree(intfc);
300}
301
302static int usb_parse_interface(struct device *ddev, int cfgno,
303    struct usb_host_config *config, unsigned char *buffer, int size,
304    u8 inums[], u8 nalts[])
305{
306	unsigned char *buffer0 = buffer;
307	struct usb_interface_descriptor	*d;
308	int inum, asnum;
309	struct usb_interface_cache *intfc;
310	struct usb_host_interface *alt;
311	int i, n;
312	int len, retval;
313	int num_ep, num_ep_orig;
314
315	d = (struct usb_interface_descriptor *) buffer;
316	buffer += d->bLength;
317	size -= d->bLength;
318
319	if (d->bLength < USB_DT_INTERFACE_SIZE)
320		goto skip_to_next_interface_descriptor;
321
322	/* Which interface entry is this? */
323	intfc = NULL;
324	inum = d->bInterfaceNumber;
325	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
326		if (inums[i] == inum) {
327			intfc = config->intf_cache[i];
328			break;
329		}
330	}
331	if (!intfc || intfc->num_altsetting >= nalts[i])
332		goto skip_to_next_interface_descriptor;
333
334	/* Check for duplicate altsetting entries */
335	asnum = d->bAlternateSetting;
336	for ((i = 0, alt = &intfc->altsetting[0]);
337	      i < intfc->num_altsetting;
338	     (++i, ++alt)) {
339		if (alt->desc.bAlternateSetting == asnum) {
340			dev_warn(ddev, "Duplicate descriptor for config %d "
341			    "interface %d altsetting %d, skipping\n",
342			    cfgno, inum, asnum);
343			goto skip_to_next_interface_descriptor;
344		}
345	}
346
347	++intfc->num_altsetting;
348	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
349
350	/* Skip over any Class Specific or Vendor Specific descriptors;
351	 * find the first endpoint or interface descriptor */
352	alt->extra = buffer;
353	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
354	    USB_DT_INTERFACE, &n);
355	alt->extralen = i;
356	if (n > 0)
357		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
358		    n, plural(n), "interface");
359	buffer += i;
360	size -= i;
361
362	/* Allocate space for the right(?) number of endpoints */
363	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
364	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
365	if (num_ep > USB_MAXENDPOINTS) {
366		dev_warn(ddev, "too many endpoints for config %d interface %d "
367		    "altsetting %d: %d, using maximum allowed: %d\n",
368		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
369		num_ep = USB_MAXENDPOINTS;
370	}
371
372	if (num_ep > 0) {
373		/* Can't allocate 0 bytes */
374		len = sizeof(struct usb_host_endpoint) * num_ep;
375		alt->endpoint = kzalloc(len, GFP_KERNEL);
376		if (!alt->endpoint)
377			return -ENOMEM;
378	}
379
380	/* Parse all the endpoint descriptors */
381	n = 0;
382	while (size > 0) {
383		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
384		     == USB_DT_INTERFACE)
385			break;
386		retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
387		    num_ep, buffer, size);
388		if (retval < 0)
389			return retval;
390		++n;
391
392		buffer += retval;
393		size -= retval;
394	}
395
396	if (n != num_ep_orig)
397		dev_warn(ddev, "config %d interface %d altsetting %d has %d "
398		    "endpoint descriptor%s, different from the interface "
399		    "descriptor's value: %d\n",
400		    cfgno, inum, asnum, n, plural(n), num_ep_orig);
401	return buffer - buffer0;
402
403skip_to_next_interface_descriptor:
404	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
405	    USB_DT_INTERFACE, NULL);
406	return buffer - buffer0 + i;
407}
408
409static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
410    struct usb_host_config *config, unsigned char *buffer, int size)
411{
412	struct device *ddev = &dev->dev;
413	unsigned char *buffer0 = buffer;
414	int cfgno;
415	int nintf, nintf_orig;
416	int i, j, n;
417	struct usb_interface_cache *intfc;
418	unsigned char *buffer2;
419	int size2;
420	struct usb_descriptor_header *header;
421	int len, retval;
422	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
423	unsigned iad_num = 0;
424
425	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
426	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
427	    config->desc.bLength < USB_DT_CONFIG_SIZE) {
 
428		dev_err(ddev, "invalid descriptor for config index %d: "
429		    "type = 0x%X, length = %d\n", cfgidx,
430		    config->desc.bDescriptorType, config->desc.bLength);
431		return -EINVAL;
432	}
433	cfgno = config->desc.bConfigurationValue;
434
435	buffer += config->desc.bLength;
436	size -= config->desc.bLength;
437
438	nintf = nintf_orig = config->desc.bNumInterfaces;
439	if (nintf > USB_MAXINTERFACES) {
440		dev_warn(ddev, "config %d has too many interfaces: %d, "
441		    "using maximum allowed: %d\n",
442		    cfgno, nintf, USB_MAXINTERFACES);
443		nintf = USB_MAXINTERFACES;
444	}
445
446	/* Go through the descriptors, checking their length and counting the
447	 * number of altsettings for each interface */
448	n = 0;
449	for ((buffer2 = buffer, size2 = size);
450	      size2 > 0;
451	     (buffer2 += header->bLength, size2 -= header->bLength)) {
452
453		if (size2 < sizeof(struct usb_descriptor_header)) {
454			dev_warn(ddev, "config %d descriptor has %d excess "
455			    "byte%s, ignoring\n",
456			    cfgno, size2, plural(size2));
457			break;
458		}
459
460		header = (struct usb_descriptor_header *) buffer2;
461		if ((header->bLength > size2) || (header->bLength < 2)) {
462			dev_warn(ddev, "config %d has an invalid descriptor "
463			    "of length %d, skipping remainder of the config\n",
464			    cfgno, header->bLength);
465			break;
466		}
467
468		if (header->bDescriptorType == USB_DT_INTERFACE) {
469			struct usb_interface_descriptor *d;
470			int inum;
471
472			d = (struct usb_interface_descriptor *) header;
473			if (d->bLength < USB_DT_INTERFACE_SIZE) {
474				dev_warn(ddev, "config %d has an invalid "
475				    "interface descriptor of length %d, "
476				    "skipping\n", cfgno, d->bLength);
477				continue;
478			}
479
480			inum = d->bInterfaceNumber;
481
482			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
483			    n >= nintf_orig) {
484				dev_warn(ddev, "config %d has more interface "
485				    "descriptors, than it declares in "
486				    "bNumInterfaces, ignoring interface "
487				    "number: %d\n", cfgno, inum);
488				continue;
489			}
490
491			if (inum >= nintf_orig)
492				dev_warn(ddev, "config %d has an invalid "
493				    "interface number: %d but max is %d\n",
494				    cfgno, inum, nintf_orig - 1);
495
496			/* Have we already encountered this interface?
497			 * Count its altsettings */
498			for (i = 0; i < n; ++i) {
499				if (inums[i] == inum)
500					break;
501			}
502			if (i < n) {
503				if (nalts[i] < 255)
504					++nalts[i];
505			} else if (n < USB_MAXINTERFACES) {
506				inums[n] = inum;
507				nalts[n] = 1;
508				++n;
509			}
510
511		} else if (header->bDescriptorType ==
512				USB_DT_INTERFACE_ASSOCIATION) {
513			if (iad_num == USB_MAXIADS) {
514				dev_warn(ddev, "found more Interface "
515					       "Association Descriptors "
516					       "than allocated for in "
517					       "configuration %d\n", cfgno);
518			} else {
519				config->intf_assoc[iad_num] =
520					(struct usb_interface_assoc_descriptor
521					*)header;
522				iad_num++;
523			}
524
525		} else if (header->bDescriptorType == USB_DT_DEVICE ||
526			    header->bDescriptorType == USB_DT_CONFIG)
527			dev_warn(ddev, "config %d contains an unexpected "
528			    "descriptor of type 0x%X, skipping\n",
529			    cfgno, header->bDescriptorType);
530
531	}	/* for ((buffer2 = buffer, size2 = size); ...) */
532	size = buffer2 - buffer;
533	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
534
535	if (n != nintf)
536		dev_warn(ddev, "config %d has %d interface%s, different from "
537		    "the descriptor's value: %d\n",
538		    cfgno, n, plural(n), nintf_orig);
539	else if (n == 0)
540		dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
541	config->desc.bNumInterfaces = nintf = n;
542
543	/* Check for missing interface numbers */
544	for (i = 0; i < nintf; ++i) {
545		for (j = 0; j < nintf; ++j) {
546			if (inums[j] == i)
547				break;
548		}
549		if (j >= nintf)
550			dev_warn(ddev, "config %d has no interface number "
551			    "%d\n", cfgno, i);
552	}
553
554	/* Allocate the usb_interface_caches and altsetting arrays */
555	for (i = 0; i < nintf; ++i) {
556		j = nalts[i];
557		if (j > USB_MAXALTSETTING) {
558			dev_warn(ddev, "too many alternate settings for "
559			    "config %d interface %d: %d, "
560			    "using maximum allowed: %d\n",
561			    cfgno, inums[i], j, USB_MAXALTSETTING);
562			nalts[i] = j = USB_MAXALTSETTING;
563		}
564
565		len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
566		config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
567		if (!intfc)
568			return -ENOMEM;
569		kref_init(&intfc->ref);
570	}
571
572	/* FIXME: parse the BOS descriptor */
573
574	/* Skip over any Class Specific or Vendor Specific descriptors;
575	 * find the first interface descriptor */
576	config->extra = buffer;
577	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
578	    USB_DT_INTERFACE, &n);
579	config->extralen = i;
580	if (n > 0)
581		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
582		    n, plural(n), "configuration");
583	buffer += i;
584	size -= i;
585
586	/* Parse all the interface/altsetting descriptors */
587	while (size > 0) {
588		retval = usb_parse_interface(ddev, cfgno, config,
589		    buffer, size, inums, nalts);
590		if (retval < 0)
591			return retval;
592
593		buffer += retval;
594		size -= retval;
595	}
596
597	/* Check for missing altsettings */
598	for (i = 0; i < nintf; ++i) {
599		intfc = config->intf_cache[i];
600		for (j = 0; j < intfc->num_altsetting; ++j) {
601			for (n = 0; n < intfc->num_altsetting; ++n) {
602				if (intfc->altsetting[n].desc.
603				    bAlternateSetting == j)
604					break;
605			}
606			if (n >= intfc->num_altsetting)
607				dev_warn(ddev, "config %d interface %d has no "
608				    "altsetting %d\n", cfgno, inums[i], j);
609		}
610	}
611
612	return 0;
613}
614
615/* hub-only!! ... and only exported for reset/reinit path.
616 * otherwise used internally on disconnect/destroy path
617 */
618void usb_destroy_configuration(struct usb_device *dev)
619{
620	int c, i;
621
622	if (!dev->config)
623		return;
624
625	if (dev->rawdescriptors) {
626		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
627			kfree(dev->rawdescriptors[i]);
628
629		kfree(dev->rawdescriptors);
630		dev->rawdescriptors = NULL;
631	}
632
633	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
634		struct usb_host_config *cf = &dev->config[c];
635
636		kfree(cf->string);
637		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
638			if (cf->intf_cache[i])
639				kref_put(&cf->intf_cache[i]->ref,
640					  usb_release_interface_cache);
641		}
642	}
643	kfree(dev->config);
644	dev->config = NULL;
645}
646
647
648/*
649 * Get the USB config descriptors, cache and parse'em
650 *
651 * hub-only!! ... and only in reset path, or usb_new_device()
652 * (used by real hubs and virtual root hubs)
653 *
654 * NOTE: if this is a WUSB device and is not authorized, we skip the
655 *       whole thing. A non-authorized USB device has no
656 *       configurations.
657 */
658int usb_get_configuration(struct usb_device *dev)
659{
660	struct device *ddev = &dev->dev;
661	int ncfg = dev->descriptor.bNumConfigurations;
662	int result = 0;
663	unsigned int cfgno, length;
664	unsigned char *bigbuffer;
665	struct usb_config_descriptor *desc;
666
667	cfgno = 0;
668	if (dev->authorized == 0)	/* Not really an error */
669		goto out_not_authorized;
670	result = -ENOMEM;
671	if (ncfg > USB_MAXCONFIG) {
672		dev_warn(ddev, "too many configurations: %d, "
673		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
674		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
675	}
676
677	if (ncfg < 1) {
678		dev_err(ddev, "no configurations\n");
679		return -EINVAL;
680	}
681
682	length = ncfg * sizeof(struct usb_host_config);
683	dev->config = kzalloc(length, GFP_KERNEL);
684	if (!dev->config)
685		goto err2;
686
687	length = ncfg * sizeof(char *);
688	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
689	if (!dev->rawdescriptors)
690		goto err2;
691
692	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
693	if (!desc)
694		goto err2;
695
696	result = 0;
697	for (; cfgno < ncfg; cfgno++) {
698		/* We grab just the first descriptor so we know how long
699		 * the whole configuration is */
700		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
701		    desc, USB_DT_CONFIG_SIZE);
702		if (result < 0) {
703			dev_err(ddev, "unable to read config index %d "
704			    "descriptor/%s: %d\n", cfgno, "start", result);
 
 
705			dev_err(ddev, "chopping to %d config(s)\n", cfgno);
706			dev->descriptor.bNumConfigurations = cfgno;
707			break;
708		} else if (result < 4) {
709			dev_err(ddev, "config index %d descriptor too short "
710			    "(expected %i, got %i)\n", cfgno,
711			    USB_DT_CONFIG_SIZE, result);
712			result = -EINVAL;
713			goto err;
714		}
715		length = max((int) le16_to_cpu(desc->wTotalLength),
716		    USB_DT_CONFIG_SIZE);
717
718		/* Now that we know the length, get the whole thing */
719		bigbuffer = kmalloc(length, GFP_KERNEL);
720		if (!bigbuffer) {
721			result = -ENOMEM;
722			goto err;
723		}
 
 
 
 
724		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
725		    bigbuffer, length);
726		if (result < 0) {
727			dev_err(ddev, "unable to read config index %d "
728			    "descriptor/%s\n", cfgno, "all");
729			kfree(bigbuffer);
730			goto err;
731		}
732		if (result < length) {
733			dev_warn(ddev, "config index %d descriptor too short "
734			    "(expected %i, got %i)\n", cfgno, length, result);
735			length = result;
736		}
737
738		dev->rawdescriptors[cfgno] = bigbuffer;
739
740		result = usb_parse_configuration(dev, cfgno,
741		    &dev->config[cfgno], bigbuffer, length);
742		if (result < 0) {
743			++cfgno;
744			goto err;
745		}
746	}
747	result = 0;
748
749err:
750	kfree(desc);
751out_not_authorized:
752	dev->descriptor.bNumConfigurations = cfgno;
753err2:
754	if (result == -ENOMEM)
755		dev_err(ddev, "out of memory\n");
756	return result;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
757}
v3.15
  1#include <linux/usb.h>
  2#include <linux/usb/ch9.h>
  3#include <linux/usb/hcd.h>
  4#include <linux/usb/quirks.h>
  5#include <linux/module.h>
 
  6#include <linux/slab.h>
  7#include <linux/device.h>
  8#include <asm/byteorder.h>
  9#include "usb.h"
 10
 11
 12#define USB_MAXALTSETTING		128	/* Hard limit */
 
 13
 14#define USB_MAXCONFIG			8	/* Arbitrary limit */
 15
 16
 17static inline const char *plural(int n)
 18{
 19	return (n == 1 ? "" : "s");
 20}
 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_ss_endpoint_companion(struct device *ddev, int cfgno,
 47		int inum, int asnum, struct usb_host_endpoint *ep,
 48		unsigned char *buffer, int size)
 49{
 50	struct usb_ss_ep_comp_descriptor *desc;
 51	int max_tx;
 52
 53	/* The SuperSpeed endpoint companion descriptor is supposed to
 54	 * be the first thing immediately following the endpoint descriptor.
 55	 */
 56	desc = (struct usb_ss_ep_comp_descriptor *) buffer;
 57	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
 58			size < USB_DT_SS_EP_COMP_SIZE) {
 59		dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
 60				" interface %d altsetting %d ep %d: "
 61				"using minimum values\n",
 62				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 63
 64		/* Fill in some default values.
 65		 * Leave bmAttributes as zero, which will mean no streams for
 66		 * bulk, and isoc won't support multiple bursts of packets.
 67		 * With bursts of only one packet, and a Mult of 1, the max
 68		 * amount of data moved per endpoint service interval is one
 69		 * packet.
 70		 */
 71		ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
 72		ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
 73		if (usb_endpoint_xfer_isoc(&ep->desc) ||
 74				usb_endpoint_xfer_int(&ep->desc))
 75			ep->ss_ep_comp.wBytesPerInterval =
 76					ep->desc.wMaxPacketSize;
 77		return;
 78	}
 79
 80	memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
 81
 82	/* Check the various values */
 83	if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
 84		dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
 85				"config %d interface %d altsetting %d ep %d: "
 86				"setting to zero\n", desc->bMaxBurst,
 87				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 88		ep->ss_ep_comp.bMaxBurst = 0;
 89	} else if (desc->bMaxBurst > 15) {
 90		dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
 91				"config %d interface %d altsetting %d ep %d: "
 92				"setting to 15\n", desc->bMaxBurst,
 93				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 94		ep->ss_ep_comp.bMaxBurst = 15;
 95	}
 96
 97	if ((usb_endpoint_xfer_control(&ep->desc) ||
 98			usb_endpoint_xfer_int(&ep->desc)) &&
 99				desc->bmAttributes != 0) {
100		dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
101				"config %d interface %d altsetting %d ep %d: "
102				"setting to zero\n",
103				usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
104				desc->bmAttributes,
105				cfgno, inum, asnum, ep->desc.bEndpointAddress);
106		ep->ss_ep_comp.bmAttributes = 0;
107	} else if (usb_endpoint_xfer_bulk(&ep->desc) &&
108			desc->bmAttributes > 16) {
109		dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
110				"config %d interface %d altsetting %d ep %d: "
111				"setting to max\n",
112				cfgno, inum, asnum, ep->desc.bEndpointAddress);
113		ep->ss_ep_comp.bmAttributes = 16;
114	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&
115			desc->bmAttributes > 2) {
116		dev_warn(ddev, "Isoc endpoint has Mult of %d in "
117				"config %d interface %d altsetting %d ep %d: "
118				"setting to 3\n", desc->bmAttributes + 1,
119				cfgno, inum, asnum, ep->desc.bEndpointAddress);
120		ep->ss_ep_comp.bmAttributes = 2;
121	}
122
123	if (usb_endpoint_xfer_isoc(&ep->desc))
124		max_tx = (desc->bMaxBurst + 1) * (desc->bmAttributes + 1) *
125			usb_endpoint_maxp(&ep->desc);
126	else if (usb_endpoint_xfer_int(&ep->desc))
127		max_tx = usb_endpoint_maxp(&ep->desc) *
128			(desc->bMaxBurst + 1);
129	else
130		max_tx = 999999;
131	if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
132		dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
133				"config %d interface %d altsetting %d ep %d: "
134				"setting to %d\n",
135				usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
136				le16_to_cpu(desc->wBytesPerInterval),
137				cfgno, inum, asnum, ep->desc.bEndpointAddress,
138				max_tx);
139		ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
140	}
141}
142
143static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
144    int asnum, struct usb_host_interface *ifp, int num_ep,
145    unsigned char *buffer, int size)
146{
147	unsigned char *buffer0 = buffer;
148	struct usb_endpoint_descriptor *d;
149	struct usb_host_endpoint *endpoint;
150	int n, i, j, retval;
151
152	d = (struct usb_endpoint_descriptor *) buffer;
153	buffer += d->bLength;
154	size -= d->bLength;
155
156	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
157		n = USB_DT_ENDPOINT_AUDIO_SIZE;
158	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
159		n = USB_DT_ENDPOINT_SIZE;
160	else {
161		dev_warn(ddev, "config %d interface %d altsetting %d has an "
162		    "invalid endpoint descriptor of length %d, skipping\n",
163		    cfgno, inum, asnum, d->bLength);
164		goto skip_to_next_endpoint_or_interface_descriptor;
165	}
166
167	i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
168	if (i >= 16 || i == 0) {
169		dev_warn(ddev, "config %d interface %d altsetting %d has an "
170		    "invalid endpoint with address 0x%X, skipping\n",
171		    cfgno, inum, asnum, d->bEndpointAddress);
172		goto skip_to_next_endpoint_or_interface_descriptor;
173	}
174
175	/* Only store as many endpoints as we have room for */
176	if (ifp->desc.bNumEndpoints >= num_ep)
177		goto skip_to_next_endpoint_or_interface_descriptor;
178
179	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
180	++ifp->desc.bNumEndpoints;
181
182	memcpy(&endpoint->desc, d, n);
183	INIT_LIST_HEAD(&endpoint->urb_list);
184
185	/* Fix up bInterval values outside the legal range. Use 32 ms if no
186	 * proper value can be guessed. */
187	i = 0;		/* i = min, j = max, n = default */
188	j = 255;
189	if (usb_endpoint_xfer_int(d)) {
190		i = 1;
191		switch (to_usb_device(ddev)->speed) {
192		case USB_SPEED_SUPER:
193		case USB_SPEED_HIGH:
194			/* Many device manufacturers are using full-speed
195			 * bInterval values in high-speed interrupt endpoint
196			 * descriptors. Try to fix those and fall back to a
197			 * 32 ms default value otherwise. */
198			n = fls(d->bInterval*8);
199			if (n == 0)
200				n = 9;	/* 32 ms = 2^(9-1) uframes */
201			j = 16;
202			break;
203		default:		/* USB_SPEED_FULL or _LOW */
204			/* For low-speed, 10 ms is the official minimum.
205			 * But some "overclocked" devices might want faster
206			 * polling so we'll allow it. */
207			n = 32;
208			break;
209		}
210	} else if (usb_endpoint_xfer_isoc(d)) {
211		i = 1;
212		j = 16;
213		switch (to_usb_device(ddev)->speed) {
214		case USB_SPEED_HIGH:
215			n = 9;		/* 32 ms = 2^(9-1) uframes */
216			break;
217		default:		/* USB_SPEED_FULL */
218			n = 6;		/* 32 ms = 2^(6-1) frames */
219			break;
220		}
221	}
222	if (d->bInterval < i || d->bInterval > j) {
223		dev_warn(ddev, "config %d interface %d altsetting %d "
224		    "endpoint 0x%X has an invalid bInterval %d, "
225		    "changing to %d\n",
226		    cfgno, inum, asnum,
227		    d->bEndpointAddress, d->bInterval, n);
228		endpoint->desc.bInterval = n;
229	}
230
231	/* Some buggy low-speed devices have Bulk endpoints, which is
232	 * explicitly forbidden by the USB spec.  In an attempt to make
233	 * them usable, we will try treating them as Interrupt endpoints.
234	 */
235	if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
236			usb_endpoint_xfer_bulk(d)) {
237		dev_warn(ddev, "config %d interface %d altsetting %d "
238		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
239		    cfgno, inum, asnum, d->bEndpointAddress);
240		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
241		endpoint->desc.bInterval = 1;
242		if (usb_endpoint_maxp(&endpoint->desc) > 8)
243			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
244	}
245
246	/*
247	 * Some buggy high speed devices have bulk endpoints using
248	 * maxpacket sizes other than 512.  High speed HCDs may not
249	 * be able to handle that particular bug, so let's warn...
250	 */
251	if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
252			&& usb_endpoint_xfer_bulk(d)) {
253		unsigned maxp;
254
255		maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
256		if (maxp != 512)
257			dev_warn(ddev, "config %d interface %d altsetting %d "
258				"bulk endpoint 0x%X has invalid maxpacket %d\n",
259				cfgno, inum, asnum, d->bEndpointAddress,
260				maxp);
261	}
262
263	/* Parse a possible SuperSpeed endpoint companion descriptor */
264	if (to_usb_device(ddev)->speed == USB_SPEED_SUPER)
265		usb_parse_ss_endpoint_companion(ddev, cfgno,
266				inum, asnum, endpoint, buffer, size);
267
268	/* Skip over any Class Specific or Vendor Specific descriptors;
269	 * find the next endpoint or interface descriptor */
270	endpoint->extra = buffer;
271	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
272			USB_DT_INTERFACE, &n);
273	endpoint->extralen = i;
274	retval = buffer - buffer0 + i;
275	if (n > 0)
276		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
277		    n, plural(n), "endpoint");
278	return retval;
279
280skip_to_next_endpoint_or_interface_descriptor:
281	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
282	    USB_DT_INTERFACE, NULL);
283	return buffer - buffer0 + i;
284}
285
286void usb_release_interface_cache(struct kref *ref)
287{
288	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
289	int j;
290
291	for (j = 0; j < intfc->num_altsetting; j++) {
292		struct usb_host_interface *alt = &intfc->altsetting[j];
293
294		kfree(alt->endpoint);
295		kfree(alt->string);
296	}
297	kfree(intfc);
298}
299
300static int usb_parse_interface(struct device *ddev, int cfgno,
301    struct usb_host_config *config, unsigned char *buffer, int size,
302    u8 inums[], u8 nalts[])
303{
304	unsigned char *buffer0 = buffer;
305	struct usb_interface_descriptor	*d;
306	int inum, asnum;
307	struct usb_interface_cache *intfc;
308	struct usb_host_interface *alt;
309	int i, n;
310	int len, retval;
311	int num_ep, num_ep_orig;
312
313	d = (struct usb_interface_descriptor *) buffer;
314	buffer += d->bLength;
315	size -= d->bLength;
316
317	if (d->bLength < USB_DT_INTERFACE_SIZE)
318		goto skip_to_next_interface_descriptor;
319
320	/* Which interface entry is this? */
321	intfc = NULL;
322	inum = d->bInterfaceNumber;
323	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
324		if (inums[i] == inum) {
325			intfc = config->intf_cache[i];
326			break;
327		}
328	}
329	if (!intfc || intfc->num_altsetting >= nalts[i])
330		goto skip_to_next_interface_descriptor;
331
332	/* Check for duplicate altsetting entries */
333	asnum = d->bAlternateSetting;
334	for ((i = 0, alt = &intfc->altsetting[0]);
335	      i < intfc->num_altsetting;
336	     (++i, ++alt)) {
337		if (alt->desc.bAlternateSetting == asnum) {
338			dev_warn(ddev, "Duplicate descriptor for config %d "
339			    "interface %d altsetting %d, skipping\n",
340			    cfgno, inum, asnum);
341			goto skip_to_next_interface_descriptor;
342		}
343	}
344
345	++intfc->num_altsetting;
346	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
347
348	/* Skip over any Class Specific or Vendor Specific descriptors;
349	 * find the first endpoint or interface descriptor */
350	alt->extra = buffer;
351	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
352	    USB_DT_INTERFACE, &n);
353	alt->extralen = i;
354	if (n > 0)
355		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
356		    n, plural(n), "interface");
357	buffer += i;
358	size -= i;
359
360	/* Allocate space for the right(?) number of endpoints */
361	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
362	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
363	if (num_ep > USB_MAXENDPOINTS) {
364		dev_warn(ddev, "too many endpoints for config %d interface %d "
365		    "altsetting %d: %d, using maximum allowed: %d\n",
366		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
367		num_ep = USB_MAXENDPOINTS;
368	}
369
370	if (num_ep > 0) {
371		/* Can't allocate 0 bytes */
372		len = sizeof(struct usb_host_endpoint) * num_ep;
373		alt->endpoint = kzalloc(len, GFP_KERNEL);
374		if (!alt->endpoint)
375			return -ENOMEM;
376	}
377
378	/* Parse all the endpoint descriptors */
379	n = 0;
380	while (size > 0) {
381		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
382		     == USB_DT_INTERFACE)
383			break;
384		retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
385		    num_ep, buffer, size);
386		if (retval < 0)
387			return retval;
388		++n;
389
390		buffer += retval;
391		size -= retval;
392	}
393
394	if (n != num_ep_orig)
395		dev_warn(ddev, "config %d interface %d altsetting %d has %d "
396		    "endpoint descriptor%s, different from the interface "
397		    "descriptor's value: %d\n",
398		    cfgno, inum, asnum, n, plural(n), num_ep_orig);
399	return buffer - buffer0;
400
401skip_to_next_interface_descriptor:
402	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
403	    USB_DT_INTERFACE, NULL);
404	return buffer - buffer0 + i;
405}
406
407static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
408    struct usb_host_config *config, unsigned char *buffer, int size)
409{
410	struct device *ddev = &dev->dev;
411	unsigned char *buffer0 = buffer;
412	int cfgno;
413	int nintf, nintf_orig;
414	int i, j, n;
415	struct usb_interface_cache *intfc;
416	unsigned char *buffer2;
417	int size2;
418	struct usb_descriptor_header *header;
419	int len, retval;
420	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
421	unsigned iad_num = 0;
422
423	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
424	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
425	    config->desc.bLength < USB_DT_CONFIG_SIZE ||
426	    config->desc.bLength > size) {
427		dev_err(ddev, "invalid descriptor for config index %d: "
428		    "type = 0x%X, length = %d\n", cfgidx,
429		    config->desc.bDescriptorType, config->desc.bLength);
430		return -EINVAL;
431	}
432	cfgno = config->desc.bConfigurationValue;
433
434	buffer += config->desc.bLength;
435	size -= config->desc.bLength;
436
437	nintf = nintf_orig = config->desc.bNumInterfaces;
438	if (nintf > USB_MAXINTERFACES) {
439		dev_warn(ddev, "config %d has too many interfaces: %d, "
440		    "using maximum allowed: %d\n",
441		    cfgno, nintf, USB_MAXINTERFACES);
442		nintf = USB_MAXINTERFACES;
443	}
444
445	/* Go through the descriptors, checking their length and counting the
446	 * number of altsettings for each interface */
447	n = 0;
448	for ((buffer2 = buffer, size2 = size);
449	      size2 > 0;
450	     (buffer2 += header->bLength, size2 -= header->bLength)) {
451
452		if (size2 < sizeof(struct usb_descriptor_header)) {
453			dev_warn(ddev, "config %d descriptor has %d excess "
454			    "byte%s, ignoring\n",
455			    cfgno, size2, plural(size2));
456			break;
457		}
458
459		header = (struct usb_descriptor_header *) buffer2;
460		if ((header->bLength > size2) || (header->bLength < 2)) {
461			dev_warn(ddev, "config %d has an invalid descriptor "
462			    "of length %d, skipping remainder of the config\n",
463			    cfgno, header->bLength);
464			break;
465		}
466
467		if (header->bDescriptorType == USB_DT_INTERFACE) {
468			struct usb_interface_descriptor *d;
469			int inum;
470
471			d = (struct usb_interface_descriptor *) header;
472			if (d->bLength < USB_DT_INTERFACE_SIZE) {
473				dev_warn(ddev, "config %d has an invalid "
474				    "interface descriptor of length %d, "
475				    "skipping\n", cfgno, d->bLength);
476				continue;
477			}
478
479			inum = d->bInterfaceNumber;
480
481			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
482			    n >= nintf_orig) {
483				dev_warn(ddev, "config %d has more interface "
484				    "descriptors, than it declares in "
485				    "bNumInterfaces, ignoring interface "
486				    "number: %d\n", cfgno, inum);
487				continue;
488			}
489
490			if (inum >= nintf_orig)
491				dev_warn(ddev, "config %d has an invalid "
492				    "interface number: %d but max is %d\n",
493				    cfgno, inum, nintf_orig - 1);
494
495			/* Have we already encountered this interface?
496			 * Count its altsettings */
497			for (i = 0; i < n; ++i) {
498				if (inums[i] == inum)
499					break;
500			}
501			if (i < n) {
502				if (nalts[i] < 255)
503					++nalts[i];
504			} else if (n < USB_MAXINTERFACES) {
505				inums[n] = inum;
506				nalts[n] = 1;
507				++n;
508			}
509
510		} else if (header->bDescriptorType ==
511				USB_DT_INTERFACE_ASSOCIATION) {
512			if (iad_num == USB_MAXIADS) {
513				dev_warn(ddev, "found more Interface "
514					       "Association Descriptors "
515					       "than allocated for in "
516					       "configuration %d\n", cfgno);
517			} else {
518				config->intf_assoc[iad_num] =
519					(struct usb_interface_assoc_descriptor
520					*)header;
521				iad_num++;
522			}
523
524		} else if (header->bDescriptorType == USB_DT_DEVICE ||
525			    header->bDescriptorType == USB_DT_CONFIG)
526			dev_warn(ddev, "config %d contains an unexpected "
527			    "descriptor of type 0x%X, skipping\n",
528			    cfgno, header->bDescriptorType);
529
530	}	/* for ((buffer2 = buffer, size2 = size); ...) */
531	size = buffer2 - buffer;
532	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
533
534	if (n != nintf)
535		dev_warn(ddev, "config %d has %d interface%s, different from "
536		    "the descriptor's value: %d\n",
537		    cfgno, n, plural(n), nintf_orig);
538	else if (n == 0)
539		dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
540	config->desc.bNumInterfaces = nintf = n;
541
542	/* Check for missing interface numbers */
543	for (i = 0; i < nintf; ++i) {
544		for (j = 0; j < nintf; ++j) {
545			if (inums[j] == i)
546				break;
547		}
548		if (j >= nintf)
549			dev_warn(ddev, "config %d has no interface number "
550			    "%d\n", cfgno, i);
551	}
552
553	/* Allocate the usb_interface_caches and altsetting arrays */
554	for (i = 0; i < nintf; ++i) {
555		j = nalts[i];
556		if (j > USB_MAXALTSETTING) {
557			dev_warn(ddev, "too many alternate settings for "
558			    "config %d interface %d: %d, "
559			    "using maximum allowed: %d\n",
560			    cfgno, inums[i], j, USB_MAXALTSETTING);
561			nalts[i] = j = USB_MAXALTSETTING;
562		}
563
564		len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
565		config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
566		if (!intfc)
567			return -ENOMEM;
568		kref_init(&intfc->ref);
569	}
570
571	/* FIXME: parse the BOS descriptor */
572
573	/* Skip over any Class Specific or Vendor Specific descriptors;
574	 * find the first interface descriptor */
575	config->extra = buffer;
576	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
577	    USB_DT_INTERFACE, &n);
578	config->extralen = i;
579	if (n > 0)
580		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
581		    n, plural(n), "configuration");
582	buffer += i;
583	size -= i;
584
585	/* Parse all the interface/altsetting descriptors */
586	while (size > 0) {
587		retval = usb_parse_interface(ddev, cfgno, config,
588		    buffer, size, inums, nalts);
589		if (retval < 0)
590			return retval;
591
592		buffer += retval;
593		size -= retval;
594	}
595
596	/* Check for missing altsettings */
597	for (i = 0; i < nintf; ++i) {
598		intfc = config->intf_cache[i];
599		for (j = 0; j < intfc->num_altsetting; ++j) {
600			for (n = 0; n < intfc->num_altsetting; ++n) {
601				if (intfc->altsetting[n].desc.
602				    bAlternateSetting == j)
603					break;
604			}
605			if (n >= intfc->num_altsetting)
606				dev_warn(ddev, "config %d interface %d has no "
607				    "altsetting %d\n", cfgno, inums[i], j);
608		}
609	}
610
611	return 0;
612}
613
614/* hub-only!! ... and only exported for reset/reinit path.
615 * otherwise used internally on disconnect/destroy path
616 */
617void usb_destroy_configuration(struct usb_device *dev)
618{
619	int c, i;
620
621	if (!dev->config)
622		return;
623
624	if (dev->rawdescriptors) {
625		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
626			kfree(dev->rawdescriptors[i]);
627
628		kfree(dev->rawdescriptors);
629		dev->rawdescriptors = NULL;
630	}
631
632	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
633		struct usb_host_config *cf = &dev->config[c];
634
635		kfree(cf->string);
636		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
637			if (cf->intf_cache[i])
638				kref_put(&cf->intf_cache[i]->ref,
639					  usb_release_interface_cache);
640		}
641	}
642	kfree(dev->config);
643	dev->config = NULL;
644}
645
646
647/*
648 * Get the USB config descriptors, cache and parse'em
649 *
650 * hub-only!! ... and only in reset path, or usb_new_device()
651 * (used by real hubs and virtual root hubs)
 
 
 
 
652 */
653int usb_get_configuration(struct usb_device *dev)
654{
655	struct device *ddev = &dev->dev;
656	int ncfg = dev->descriptor.bNumConfigurations;
657	int result = 0;
658	unsigned int cfgno, length;
659	unsigned char *bigbuffer;
660	struct usb_config_descriptor *desc;
661
662	cfgno = 0;
 
 
663	result = -ENOMEM;
664	if (ncfg > USB_MAXCONFIG) {
665		dev_warn(ddev, "too many configurations: %d, "
666		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
667		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
668	}
669
670	if (ncfg < 1) {
671		dev_err(ddev, "no configurations\n");
672		return -EINVAL;
673	}
674
675	length = ncfg * sizeof(struct usb_host_config);
676	dev->config = kzalloc(length, GFP_KERNEL);
677	if (!dev->config)
678		goto err2;
679
680	length = ncfg * sizeof(char *);
681	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
682	if (!dev->rawdescriptors)
683		goto err2;
684
685	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
686	if (!desc)
687		goto err2;
688
689	result = 0;
690	for (; cfgno < ncfg; cfgno++) {
691		/* We grab just the first descriptor so we know how long
692		 * the whole configuration is */
693		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
694		    desc, USB_DT_CONFIG_SIZE);
695		if (result < 0) {
696			dev_err(ddev, "unable to read config index %d "
697			    "descriptor/%s: %d\n", cfgno, "start", result);
698			if (result != -EPIPE)
699				goto err;
700			dev_err(ddev, "chopping to %d config(s)\n", cfgno);
701			dev->descriptor.bNumConfigurations = cfgno;
702			break;
703		} else if (result < 4) {
704			dev_err(ddev, "config index %d descriptor too short "
705			    "(expected %i, got %i)\n", cfgno,
706			    USB_DT_CONFIG_SIZE, result);
707			result = -EINVAL;
708			goto err;
709		}
710		length = max((int) le16_to_cpu(desc->wTotalLength),
711		    USB_DT_CONFIG_SIZE);
712
713		/* Now that we know the length, get the whole thing */
714		bigbuffer = kmalloc(length, GFP_KERNEL);
715		if (!bigbuffer) {
716			result = -ENOMEM;
717			goto err;
718		}
719
720		if (dev->quirks & USB_QUIRK_DELAY_INIT)
721			msleep(100);
722
723		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
724		    bigbuffer, length);
725		if (result < 0) {
726			dev_err(ddev, "unable to read config index %d "
727			    "descriptor/%s\n", cfgno, "all");
728			kfree(bigbuffer);
729			goto err;
730		}
731		if (result < length) {
732			dev_warn(ddev, "config index %d descriptor too short "
733			    "(expected %i, got %i)\n", cfgno, length, result);
734			length = result;
735		}
736
737		dev->rawdescriptors[cfgno] = bigbuffer;
738
739		result = usb_parse_configuration(dev, cfgno,
740		    &dev->config[cfgno], bigbuffer, length);
741		if (result < 0) {
742			++cfgno;
743			goto err;
744		}
745	}
746	result = 0;
747
748err:
749	kfree(desc);
 
750	dev->descriptor.bNumConfigurations = cfgno;
751err2:
752	if (result == -ENOMEM)
753		dev_err(ddev, "out of memory\n");
754	return result;
755}
756
757void usb_release_bos_descriptor(struct usb_device *dev)
758{
759	if (dev->bos) {
760		kfree(dev->bos->desc);
761		kfree(dev->bos);
762		dev->bos = NULL;
763	}
764}
765
766/* Get BOS descriptor set */
767int usb_get_bos_descriptor(struct usb_device *dev)
768{
769	struct device *ddev = &dev->dev;
770	struct usb_bos_descriptor *bos;
771	struct usb_dev_cap_header *cap;
772	unsigned char *buffer;
773	int length, total_len, num, i;
774	int ret;
775
776	bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
777	if (!bos)
778		return -ENOMEM;
779
780	/* Get BOS descriptor */
781	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
782	if (ret < USB_DT_BOS_SIZE) {
783		dev_err(ddev, "unable to get BOS descriptor\n");
784		if (ret >= 0)
785			ret = -ENOMSG;
786		kfree(bos);
787		return ret;
788	}
789
790	length = bos->bLength;
791	total_len = le16_to_cpu(bos->wTotalLength);
792	num = bos->bNumDeviceCaps;
793	kfree(bos);
794	if (total_len < length)
795		return -EINVAL;
796
797	dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
798	if (!dev->bos)
799		return -ENOMEM;
800
801	/* Now let's get the whole BOS descriptor set */
802	buffer = kzalloc(total_len, GFP_KERNEL);
803	if (!buffer) {
804		ret = -ENOMEM;
805		goto err;
806	}
807	dev->bos->desc = (struct usb_bos_descriptor *)buffer;
808
809	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
810	if (ret < total_len) {
811		dev_err(ddev, "unable to get BOS descriptor set\n");
812		if (ret >= 0)
813			ret = -ENOMSG;
814		goto err;
815	}
816	total_len -= length;
817
818	for (i = 0; i < num; i++) {
819		buffer += length;
820		cap = (struct usb_dev_cap_header *)buffer;
821		length = cap->bLength;
822
823		if (total_len < length)
824			break;
825		total_len -= length;
826
827		if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
828			dev_warn(ddev, "descriptor type invalid, skip\n");
829			continue;
830		}
831
832		switch (cap->bDevCapabilityType) {
833		case USB_CAP_TYPE_WIRELESS_USB:
834			/* Wireless USB cap descriptor is handled by wusb */
835			break;
836		case USB_CAP_TYPE_EXT:
837			dev->bos->ext_cap =
838				(struct usb_ext_cap_descriptor *)buffer;
839			break;
840		case USB_SS_CAP_TYPE:
841			dev->bos->ss_cap =
842				(struct usb_ss_cap_descriptor *)buffer;
843			break;
844		case CONTAINER_ID_TYPE:
845			dev->bos->ss_id =
846				(struct usb_ss_container_id_descriptor *)buffer;
847			break;
848		default:
849			break;
850		}
851	}
852
853	return 0;
854
855err:
856	usb_release_bos_descriptor(dev);
857	return ret;
858}