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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}
v4.6
  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_ssp_isoc_endpoint_companion(struct device *ddev,
 47		int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
 48		unsigned char *buffer, int size)
 49{
 50	struct usb_ssp_isoc_ep_comp_descriptor *desc;
 51
 52	/*
 53	 * The SuperSpeedPlus Isoc endpoint companion descriptor immediately
 54	 * follows the SuperSpeed Endpoint Companion descriptor
 55	 */
 56	desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;
 57	if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||
 58	    size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {
 59		dev_warn(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"
 60			 "for config %d interface %d altsetting %d ep %d.\n",
 61			 cfgno, inum, asnum, ep->desc.bEndpointAddress);
 62		return;
 63	}
 64	memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);
 65}
 66
 67static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
 68		int inum, int asnum, struct usb_host_endpoint *ep,
 69		unsigned char *buffer, int size)
 70{
 71	struct usb_ss_ep_comp_descriptor *desc;
 72	int max_tx;
 73
 74	/* The SuperSpeed endpoint companion descriptor is supposed to
 75	 * be the first thing immediately following the endpoint descriptor.
 76	 */
 77	desc = (struct usb_ss_ep_comp_descriptor *) buffer;
 78
 79	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
 80			size < USB_DT_SS_EP_COMP_SIZE) {
 81		dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
 82				" interface %d altsetting %d ep %d: "
 83				"using minimum values\n",
 84				cfgno, inum, asnum, ep->desc.bEndpointAddress);
 85
 86		/* Fill in some default values.
 87		 * Leave bmAttributes as zero, which will mean no streams for
 88		 * bulk, and isoc won't support multiple bursts of packets.
 89		 * With bursts of only one packet, and a Mult of 1, the max
 90		 * amount of data moved per endpoint service interval is one
 91		 * packet.
 92		 */
 93		ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
 94		ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
 95		if (usb_endpoint_xfer_isoc(&ep->desc) ||
 96				usb_endpoint_xfer_int(&ep->desc))
 97			ep->ss_ep_comp.wBytesPerInterval =
 98					ep->desc.wMaxPacketSize;
 99		return;
100	}
101	buffer += desc->bLength;
102	size -= desc->bLength;
103	memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
104
105	/* Check the various values */
106	if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
107		dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
108				"config %d interface %d altsetting %d ep %d: "
109				"setting to zero\n", desc->bMaxBurst,
110				cfgno, inum, asnum, ep->desc.bEndpointAddress);
111		ep->ss_ep_comp.bMaxBurst = 0;
112	} else if (desc->bMaxBurst > 15) {
113		dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
114				"config %d interface %d altsetting %d ep %d: "
115				"setting to 15\n", desc->bMaxBurst,
116				cfgno, inum, asnum, ep->desc.bEndpointAddress);
117		ep->ss_ep_comp.bMaxBurst = 15;
118	}
119
120	if ((usb_endpoint_xfer_control(&ep->desc) ||
121			usb_endpoint_xfer_int(&ep->desc)) &&
122				desc->bmAttributes != 0) {
123		dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
124				"config %d interface %d altsetting %d ep %d: "
125				"setting to zero\n",
126				usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
127				desc->bmAttributes,
128				cfgno, inum, asnum, ep->desc.bEndpointAddress);
129		ep->ss_ep_comp.bmAttributes = 0;
130	} else if (usb_endpoint_xfer_bulk(&ep->desc) &&
131			desc->bmAttributes > 16) {
132		dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
133				"config %d interface %d altsetting %d ep %d: "
134				"setting to max\n",
135				cfgno, inum, asnum, ep->desc.bEndpointAddress);
136		ep->ss_ep_comp.bmAttributes = 16;
137	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&
138		   !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
139		   USB_SS_MULT(desc->bmAttributes) > 3) {
140		dev_warn(ddev, "Isoc endpoint has Mult of %d in "
141				"config %d interface %d altsetting %d ep %d: "
142				"setting to 3\n",
143				USB_SS_MULT(desc->bmAttributes),
144				cfgno, inum, asnum, ep->desc.bEndpointAddress);
145		ep->ss_ep_comp.bmAttributes = 2;
146	}
147
148	if (usb_endpoint_xfer_isoc(&ep->desc))
149		max_tx = (desc->bMaxBurst + 1) *
150			(USB_SS_MULT(desc->bmAttributes)) *
151			usb_endpoint_maxp(&ep->desc);
152	else if (usb_endpoint_xfer_int(&ep->desc))
153		max_tx = usb_endpoint_maxp(&ep->desc) *
154			(desc->bMaxBurst + 1);
155	else
156		max_tx = 999999;
157	if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
158		dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
159				"config %d interface %d altsetting %d ep %d: "
160				"setting to %d\n",
161				usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
162				le16_to_cpu(desc->wBytesPerInterval),
163				cfgno, inum, asnum, ep->desc.bEndpointAddress,
164				max_tx);
165		ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
166	}
167	/* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
168	if (usb_endpoint_xfer_isoc(&ep->desc) &&
169	    USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
170		usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
171							ep, buffer, size);
172}
173
174static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
175    int asnum, struct usb_host_interface *ifp, int num_ep,
176    unsigned char *buffer, int size)
177{
178	unsigned char *buffer0 = buffer;
179	struct usb_endpoint_descriptor *d;
180	struct usb_host_endpoint *endpoint;
181	int n, i, j, retval;
182
183	d = (struct usb_endpoint_descriptor *) buffer;
184	buffer += d->bLength;
185	size -= d->bLength;
186
187	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
188		n = USB_DT_ENDPOINT_AUDIO_SIZE;
189	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
190		n = USB_DT_ENDPOINT_SIZE;
191	else {
192		dev_warn(ddev, "config %d interface %d altsetting %d has an "
193		    "invalid endpoint descriptor of length %d, skipping\n",
194		    cfgno, inum, asnum, d->bLength);
195		goto skip_to_next_endpoint_or_interface_descriptor;
196	}
197
198	i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
199	if (i >= 16 || i == 0) {
200		dev_warn(ddev, "config %d interface %d altsetting %d has an "
201		    "invalid endpoint with address 0x%X, skipping\n",
202		    cfgno, inum, asnum, d->bEndpointAddress);
203		goto skip_to_next_endpoint_or_interface_descriptor;
204	}
205
206	/* Only store as many endpoints as we have room for */
207	if (ifp->desc.bNumEndpoints >= num_ep)
208		goto skip_to_next_endpoint_or_interface_descriptor;
209
210	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
211	++ifp->desc.bNumEndpoints;
212
213	memcpy(&endpoint->desc, d, n);
214	INIT_LIST_HEAD(&endpoint->urb_list);
215
216	/* Fix up bInterval values outside the legal range. Use 32 ms if no
217	 * proper value can be guessed. */
218	i = 0;		/* i = min, j = max, n = default */
219	j = 255;
220	if (usb_endpoint_xfer_int(d)) {
221		i = 1;
222		switch (to_usb_device(ddev)->speed) {
223		case USB_SPEED_SUPER_PLUS:
224		case USB_SPEED_SUPER:
225		case USB_SPEED_HIGH:
226			/* Many device manufacturers are using full-speed
227			 * bInterval values in high-speed interrupt endpoint
228			 * descriptors. Try to fix those and fall back to a
229			 * 32 ms default value otherwise. */
230			n = fls(d->bInterval*8);
231			if (n == 0)
232				n = 9;	/* 32 ms = 2^(9-1) uframes */
233			j = 16;
234
235			/*
236			 * Adjust bInterval for quirked devices.
237			 * This quirk fixes bIntervals reported in
238			 * linear microframes.
239			 */
240			if (to_usb_device(ddev)->quirks &
241				USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
242				n = clamp(fls(d->bInterval), i, j);
243				i = j = n;
244			}
245			break;
246		default:		/* USB_SPEED_FULL or _LOW */
247			/* For low-speed, 10 ms is the official minimum.
248			 * But some "overclocked" devices might want faster
249			 * polling so we'll allow it. */
250			n = 32;
251			break;
252		}
253	} else if (usb_endpoint_xfer_isoc(d)) {
254		i = 1;
255		j = 16;
256		switch (to_usb_device(ddev)->speed) {
257		case USB_SPEED_HIGH:
258			n = 9;		/* 32 ms = 2^(9-1) uframes */
259			break;
260		default:		/* USB_SPEED_FULL */
261			n = 6;		/* 32 ms = 2^(6-1) frames */
262			break;
263		}
264	}
265	if (d->bInterval < i || d->bInterval > j) {
266		dev_warn(ddev, "config %d interface %d altsetting %d "
267		    "endpoint 0x%X has an invalid bInterval %d, "
268		    "changing to %d\n",
269		    cfgno, inum, asnum,
270		    d->bEndpointAddress, d->bInterval, n);
271		endpoint->desc.bInterval = n;
272	}
273
274	/* Some buggy low-speed devices have Bulk endpoints, which is
275	 * explicitly forbidden by the USB spec.  In an attempt to make
276	 * them usable, we will try treating them as Interrupt endpoints.
277	 */
278	if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
279			usb_endpoint_xfer_bulk(d)) {
280		dev_warn(ddev, "config %d interface %d altsetting %d "
281		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
282		    cfgno, inum, asnum, d->bEndpointAddress);
283		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
284		endpoint->desc.bInterval = 1;
285		if (usb_endpoint_maxp(&endpoint->desc) > 8)
286			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
287	}
288
289	/*
290	 * Some buggy high speed devices have bulk endpoints using
291	 * maxpacket sizes other than 512.  High speed HCDs may not
292	 * be able to handle that particular bug, so let's warn...
293	 */
294	if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
295			&& usb_endpoint_xfer_bulk(d)) {
296		unsigned maxp;
297
298		maxp = usb_endpoint_maxp(&endpoint->desc) & 0x07ff;
299		if (maxp != 512)
300			dev_warn(ddev, "config %d interface %d altsetting %d "
301				"bulk endpoint 0x%X has invalid maxpacket %d\n",
302				cfgno, inum, asnum, d->bEndpointAddress,
303				maxp);
304	}
305
306	/* Parse a possible SuperSpeed endpoint companion descriptor */
307	if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
308		usb_parse_ss_endpoint_companion(ddev, cfgno,
309				inum, asnum, endpoint, buffer, size);
310
311	/* Skip over any Class Specific or Vendor Specific descriptors;
312	 * find the next endpoint or interface descriptor */
313	endpoint->extra = buffer;
314	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
315			USB_DT_INTERFACE, &n);
316	endpoint->extralen = i;
317	retval = buffer - buffer0 + i;
318	if (n > 0)
319		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
320		    n, plural(n), "endpoint");
321	return retval;
322
323skip_to_next_endpoint_or_interface_descriptor:
324	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
325	    USB_DT_INTERFACE, NULL);
326	return buffer - buffer0 + i;
327}
328
329void usb_release_interface_cache(struct kref *ref)
330{
331	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
332	int j;
333
334	for (j = 0; j < intfc->num_altsetting; j++) {
335		struct usb_host_interface *alt = &intfc->altsetting[j];
336
337		kfree(alt->endpoint);
338		kfree(alt->string);
339	}
340	kfree(intfc);
341}
342
343static int usb_parse_interface(struct device *ddev, int cfgno,
344    struct usb_host_config *config, unsigned char *buffer, int size,
345    u8 inums[], u8 nalts[])
346{
347	unsigned char *buffer0 = buffer;
348	struct usb_interface_descriptor	*d;
349	int inum, asnum;
350	struct usb_interface_cache *intfc;
351	struct usb_host_interface *alt;
352	int i, n;
353	int len, retval;
354	int num_ep, num_ep_orig;
355
356	d = (struct usb_interface_descriptor *) buffer;
357	buffer += d->bLength;
358	size -= d->bLength;
359
360	if (d->bLength < USB_DT_INTERFACE_SIZE)
361		goto skip_to_next_interface_descriptor;
362
363	/* Which interface entry is this? */
364	intfc = NULL;
365	inum = d->bInterfaceNumber;
366	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
367		if (inums[i] == inum) {
368			intfc = config->intf_cache[i];
369			break;
370		}
371	}
372	if (!intfc || intfc->num_altsetting >= nalts[i])
373		goto skip_to_next_interface_descriptor;
374
375	/* Check for duplicate altsetting entries */
376	asnum = d->bAlternateSetting;
377	for ((i = 0, alt = &intfc->altsetting[0]);
378	      i < intfc->num_altsetting;
379	     (++i, ++alt)) {
380		if (alt->desc.bAlternateSetting == asnum) {
381			dev_warn(ddev, "Duplicate descriptor for config %d "
382			    "interface %d altsetting %d, skipping\n",
383			    cfgno, inum, asnum);
384			goto skip_to_next_interface_descriptor;
385		}
386	}
387
388	++intfc->num_altsetting;
389	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
390
391	/* Skip over any Class Specific or Vendor Specific descriptors;
392	 * find the first endpoint or interface descriptor */
393	alt->extra = buffer;
394	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
395	    USB_DT_INTERFACE, &n);
396	alt->extralen = i;
397	if (n > 0)
398		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
399		    n, plural(n), "interface");
400	buffer += i;
401	size -= i;
402
403	/* Allocate space for the right(?) number of endpoints */
404	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
405	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
406	if (num_ep > USB_MAXENDPOINTS) {
407		dev_warn(ddev, "too many endpoints for config %d interface %d "
408		    "altsetting %d: %d, using maximum allowed: %d\n",
409		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
410		num_ep = USB_MAXENDPOINTS;
411	}
412
413	if (num_ep > 0) {
414		/* Can't allocate 0 bytes */
415		len = sizeof(struct usb_host_endpoint) * num_ep;
416		alt->endpoint = kzalloc(len, GFP_KERNEL);
417		if (!alt->endpoint)
418			return -ENOMEM;
419	}
420
421	/* Parse all the endpoint descriptors */
422	n = 0;
423	while (size > 0) {
424		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
425		     == USB_DT_INTERFACE)
426			break;
427		retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
428		    num_ep, buffer, size);
429		if (retval < 0)
430			return retval;
431		++n;
432
433		buffer += retval;
434		size -= retval;
435	}
436
437	if (n != num_ep_orig)
438		dev_warn(ddev, "config %d interface %d altsetting %d has %d "
439		    "endpoint descriptor%s, different from the interface "
440		    "descriptor's value: %d\n",
441		    cfgno, inum, asnum, n, plural(n), num_ep_orig);
442	return buffer - buffer0;
443
444skip_to_next_interface_descriptor:
445	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
446	    USB_DT_INTERFACE, NULL);
447	return buffer - buffer0 + i;
448}
449
450static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
451    struct usb_host_config *config, unsigned char *buffer, int size)
452{
453	struct device *ddev = &dev->dev;
454	unsigned char *buffer0 = buffer;
455	int cfgno;
456	int nintf, nintf_orig;
457	int i, j, n;
458	struct usb_interface_cache *intfc;
459	unsigned char *buffer2;
460	int size2;
461	struct usb_descriptor_header *header;
462	int len, retval;
463	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
464	unsigned iad_num = 0;
465
466	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
467	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
468	    config->desc.bLength < USB_DT_CONFIG_SIZE ||
469	    config->desc.bLength > size) {
470		dev_err(ddev, "invalid descriptor for config index %d: "
471		    "type = 0x%X, length = %d\n", cfgidx,
472		    config->desc.bDescriptorType, config->desc.bLength);
473		return -EINVAL;
474	}
475	cfgno = config->desc.bConfigurationValue;
476
477	buffer += config->desc.bLength;
478	size -= config->desc.bLength;
479
480	nintf = nintf_orig = config->desc.bNumInterfaces;
481	if (nintf > USB_MAXINTERFACES) {
482		dev_warn(ddev, "config %d has too many interfaces: %d, "
483		    "using maximum allowed: %d\n",
484		    cfgno, nintf, USB_MAXINTERFACES);
485		nintf = USB_MAXINTERFACES;
486	}
487
488	/* Go through the descriptors, checking their length and counting the
489	 * number of altsettings for each interface */
490	n = 0;
491	for ((buffer2 = buffer, size2 = size);
492	      size2 > 0;
493	     (buffer2 += header->bLength, size2 -= header->bLength)) {
494
495		if (size2 < sizeof(struct usb_descriptor_header)) {
496			dev_warn(ddev, "config %d descriptor has %d excess "
497			    "byte%s, ignoring\n",
498			    cfgno, size2, plural(size2));
499			break;
500		}
501
502		header = (struct usb_descriptor_header *) buffer2;
503		if ((header->bLength > size2) || (header->bLength < 2)) {
504			dev_warn(ddev, "config %d has an invalid descriptor "
505			    "of length %d, skipping remainder of the config\n",
506			    cfgno, header->bLength);
507			break;
508		}
509
510		if (header->bDescriptorType == USB_DT_INTERFACE) {
511			struct usb_interface_descriptor *d;
512			int inum;
513
514			d = (struct usb_interface_descriptor *) header;
515			if (d->bLength < USB_DT_INTERFACE_SIZE) {
516				dev_warn(ddev, "config %d has an invalid "
517				    "interface descriptor of length %d, "
518				    "skipping\n", cfgno, d->bLength);
519				continue;
520			}
521
522			inum = d->bInterfaceNumber;
523
524			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
525			    n >= nintf_orig) {
526				dev_warn(ddev, "config %d has more interface "
527				    "descriptors, than it declares in "
528				    "bNumInterfaces, ignoring interface "
529				    "number: %d\n", cfgno, inum);
530				continue;
531			}
532
533			if (inum >= nintf_orig)
534				dev_warn(ddev, "config %d has an invalid "
535				    "interface number: %d but max is %d\n",
536				    cfgno, inum, nintf_orig - 1);
537
538			/* Have we already encountered this interface?
539			 * Count its altsettings */
540			for (i = 0; i < n; ++i) {
541				if (inums[i] == inum)
542					break;
543			}
544			if (i < n) {
545				if (nalts[i] < 255)
546					++nalts[i];
547			} else if (n < USB_MAXINTERFACES) {
548				inums[n] = inum;
549				nalts[n] = 1;
550				++n;
551			}
552
553		} else if (header->bDescriptorType ==
554				USB_DT_INTERFACE_ASSOCIATION) {
555			if (iad_num == USB_MAXIADS) {
556				dev_warn(ddev, "found more Interface "
557					       "Association Descriptors "
558					       "than allocated for in "
559					       "configuration %d\n", cfgno);
560			} else {
561				config->intf_assoc[iad_num] =
562					(struct usb_interface_assoc_descriptor
563					*)header;
564				iad_num++;
565			}
566
567		} else if (header->bDescriptorType == USB_DT_DEVICE ||
568			    header->bDescriptorType == USB_DT_CONFIG)
569			dev_warn(ddev, "config %d contains an unexpected "
570			    "descriptor of type 0x%X, skipping\n",
571			    cfgno, header->bDescriptorType);
572
573	}	/* for ((buffer2 = buffer, size2 = size); ...) */
574	size = buffer2 - buffer;
575	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
576
577	if (n != nintf)
578		dev_warn(ddev, "config %d has %d interface%s, different from "
579		    "the descriptor's value: %d\n",
580		    cfgno, n, plural(n), nintf_orig);
581	else if (n == 0)
582		dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
583	config->desc.bNumInterfaces = nintf = n;
584
585	/* Check for missing interface numbers */
586	for (i = 0; i < nintf; ++i) {
587		for (j = 0; j < nintf; ++j) {
588			if (inums[j] == i)
589				break;
590		}
591		if (j >= nintf)
592			dev_warn(ddev, "config %d has no interface number "
593			    "%d\n", cfgno, i);
594	}
595
596	/* Allocate the usb_interface_caches and altsetting arrays */
597	for (i = 0; i < nintf; ++i) {
598		j = nalts[i];
599		if (j > USB_MAXALTSETTING) {
600			dev_warn(ddev, "too many alternate settings for "
601			    "config %d interface %d: %d, "
602			    "using maximum allowed: %d\n",
603			    cfgno, inums[i], j, USB_MAXALTSETTING);
604			nalts[i] = j = USB_MAXALTSETTING;
605		}
606
607		len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
608		config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
609		if (!intfc)
610			return -ENOMEM;
611		kref_init(&intfc->ref);
612	}
613
614	/* FIXME: parse the BOS descriptor */
615
616	/* Skip over any Class Specific or Vendor Specific descriptors;
617	 * find the first interface descriptor */
618	config->extra = buffer;
619	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
620	    USB_DT_INTERFACE, &n);
621	config->extralen = i;
622	if (n > 0)
623		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
624		    n, plural(n), "configuration");
625	buffer += i;
626	size -= i;
627
628	/* Parse all the interface/altsetting descriptors */
629	while (size > 0) {
630		retval = usb_parse_interface(ddev, cfgno, config,
631		    buffer, size, inums, nalts);
632		if (retval < 0)
633			return retval;
634
635		buffer += retval;
636		size -= retval;
637	}
638
639	/* Check for missing altsettings */
640	for (i = 0; i < nintf; ++i) {
641		intfc = config->intf_cache[i];
642		for (j = 0; j < intfc->num_altsetting; ++j) {
643			for (n = 0; n < intfc->num_altsetting; ++n) {
644				if (intfc->altsetting[n].desc.
645				    bAlternateSetting == j)
646					break;
647			}
648			if (n >= intfc->num_altsetting)
649				dev_warn(ddev, "config %d interface %d has no "
650				    "altsetting %d\n", cfgno, inums[i], j);
651		}
652	}
653
654	return 0;
655}
656
657/* hub-only!! ... and only exported for reset/reinit path.
658 * otherwise used internally on disconnect/destroy path
659 */
660void usb_destroy_configuration(struct usb_device *dev)
661{
662	int c, i;
663
664	if (!dev->config)
665		return;
666
667	if (dev->rawdescriptors) {
668		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
669			kfree(dev->rawdescriptors[i]);
670
671		kfree(dev->rawdescriptors);
672		dev->rawdescriptors = NULL;
673	}
674
675	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
676		struct usb_host_config *cf = &dev->config[c];
677
678		kfree(cf->string);
679		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
680			if (cf->intf_cache[i])
681				kref_put(&cf->intf_cache[i]->ref,
682					  usb_release_interface_cache);
683		}
684	}
685	kfree(dev->config);
686	dev->config = NULL;
687}
688
689
690/*
691 * Get the USB config descriptors, cache and parse'em
692 *
693 * hub-only!! ... and only in reset path, or usb_new_device()
694 * (used by real hubs and virtual root hubs)
 
 
 
 
695 */
696int usb_get_configuration(struct usb_device *dev)
697{
698	struct device *ddev = &dev->dev;
699	int ncfg = dev->descriptor.bNumConfigurations;
700	int result = 0;
701	unsigned int cfgno, length;
702	unsigned char *bigbuffer;
703	struct usb_config_descriptor *desc;
704
705	cfgno = 0;
 
 
706	result = -ENOMEM;
707	if (ncfg > USB_MAXCONFIG) {
708		dev_warn(ddev, "too many configurations: %d, "
709		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
710		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
711	}
712
713	if (ncfg < 1) {
714		dev_err(ddev, "no configurations\n");
715		return -EINVAL;
716	}
717
718	length = ncfg * sizeof(struct usb_host_config);
719	dev->config = kzalloc(length, GFP_KERNEL);
720	if (!dev->config)
721		goto err2;
722
723	length = ncfg * sizeof(char *);
724	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
725	if (!dev->rawdescriptors)
726		goto err2;
727
728	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
729	if (!desc)
730		goto err2;
731
732	result = 0;
733	for (; cfgno < ncfg; cfgno++) {
734		/* We grab just the first descriptor so we know how long
735		 * the whole configuration is */
736		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
737		    desc, USB_DT_CONFIG_SIZE);
738		if (result < 0) {
739			dev_err(ddev, "unable to read config index %d "
740			    "descriptor/%s: %d\n", cfgno, "start", result);
741			if (result != -EPIPE)
742				goto err;
743			dev_err(ddev, "chopping to %d config(s)\n", cfgno);
744			dev->descriptor.bNumConfigurations = cfgno;
745			break;
746		} else if (result < 4) {
747			dev_err(ddev, "config index %d descriptor too short "
748			    "(expected %i, got %i)\n", cfgno,
749			    USB_DT_CONFIG_SIZE, result);
750			result = -EINVAL;
751			goto err;
752		}
753		length = max((int) le16_to_cpu(desc->wTotalLength),
754		    USB_DT_CONFIG_SIZE);
755
756		/* Now that we know the length, get the whole thing */
757		bigbuffer = kmalloc(length, GFP_KERNEL);
758		if (!bigbuffer) {
759			result = -ENOMEM;
760			goto err;
761		}
762
763		if (dev->quirks & USB_QUIRK_DELAY_INIT)
764			msleep(100);
765
766		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
767		    bigbuffer, length);
768		if (result < 0) {
769			dev_err(ddev, "unable to read config index %d "
770			    "descriptor/%s\n", cfgno, "all");
771			kfree(bigbuffer);
772			goto err;
773		}
774		if (result < length) {
775			dev_warn(ddev, "config index %d descriptor too short "
776			    "(expected %i, got %i)\n", cfgno, length, result);
777			length = result;
778		}
779
780		dev->rawdescriptors[cfgno] = bigbuffer;
781
782		result = usb_parse_configuration(dev, cfgno,
783		    &dev->config[cfgno], bigbuffer, length);
784		if (result < 0) {
785			++cfgno;
786			goto err;
787		}
788	}
789	result = 0;
790
791err:
792	kfree(desc);
 
793	dev->descriptor.bNumConfigurations = cfgno;
794err2:
795	if (result == -ENOMEM)
796		dev_err(ddev, "out of memory\n");
797	return result;
798}
799
800void usb_release_bos_descriptor(struct usb_device *dev)
801{
802	if (dev->bos) {
803		kfree(dev->bos->desc);
804		kfree(dev->bos);
805		dev->bos = NULL;
806	}
807}
808
809/* Get BOS descriptor set */
810int usb_get_bos_descriptor(struct usb_device *dev)
811{
812	struct device *ddev = &dev->dev;
813	struct usb_bos_descriptor *bos;
814	struct usb_dev_cap_header *cap;
815	unsigned char *buffer;
816	int length, total_len, num, i;
817	int ret;
818
819	bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
820	if (!bos)
821		return -ENOMEM;
822
823	/* Get BOS descriptor */
824	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
825	if (ret < USB_DT_BOS_SIZE) {
826		dev_err(ddev, "unable to get BOS descriptor\n");
827		if (ret >= 0)
828			ret = -ENOMSG;
829		kfree(bos);
830		return ret;
831	}
832
833	length = bos->bLength;
834	total_len = le16_to_cpu(bos->wTotalLength);
835	num = bos->bNumDeviceCaps;
836	kfree(bos);
837	if (total_len < length)
838		return -EINVAL;
839
840	dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
841	if (!dev->bos)
842		return -ENOMEM;
843
844	/* Now let's get the whole BOS descriptor set */
845	buffer = kzalloc(total_len, GFP_KERNEL);
846	if (!buffer) {
847		ret = -ENOMEM;
848		goto err;
849	}
850	dev->bos->desc = (struct usb_bos_descriptor *)buffer;
851
852	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
853	if (ret < total_len) {
854		dev_err(ddev, "unable to get BOS descriptor set\n");
855		if (ret >= 0)
856			ret = -ENOMSG;
857		goto err;
858	}
859	total_len -= length;
860
861	for (i = 0; i < num; i++) {
862		buffer += length;
863		cap = (struct usb_dev_cap_header *)buffer;
864		length = cap->bLength;
865
866		if (total_len < length)
867			break;
868		total_len -= length;
869
870		if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
871			dev_warn(ddev, "descriptor type invalid, skip\n");
872			continue;
873		}
874
875		switch (cap->bDevCapabilityType) {
876		case USB_CAP_TYPE_WIRELESS_USB:
877			/* Wireless USB cap descriptor is handled by wusb */
878			break;
879		case USB_CAP_TYPE_EXT:
880			dev->bos->ext_cap =
881				(struct usb_ext_cap_descriptor *)buffer;
882			break;
883		case USB_SS_CAP_TYPE:
884			dev->bos->ss_cap =
885				(struct usb_ss_cap_descriptor *)buffer;
886			break;
887		case USB_SSP_CAP_TYPE:
888			dev->bos->ssp_cap =
889				(struct usb_ssp_cap_descriptor *)buffer;
890			break;
891		case CONTAINER_ID_TYPE:
892			dev->bos->ss_id =
893				(struct usb_ss_container_id_descriptor *)buffer;
894			break;
895		case USB_PTM_CAP_TYPE:
896			dev->bos->ptm_cap =
897				(struct usb_ptm_cap_descriptor *)buffer;
898		default:
899			break;
900		}
901	}
902
903	return 0;
904
905err:
906	usb_release_bos_descriptor(dev);
907	return ret;
908}