1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Released under the GPLv2 only.
4 */
5
6#include <linux/usb.h>
7#include <linux/usb/ch9.h>
8#include <linux/usb/hcd.h>
9#include <linux/usb/quirks.h>
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/string_choices.h>
13#include <linux/device.h>
14#include <asm/byteorder.h>
15#include "usb.h"
16
17
18#define USB_MAXALTSETTING 128 /* Hard limit */
19
20#define USB_MAXCONFIG 8 /* Arbitrary limit */
21
22static int find_next_descriptor(unsigned char *buffer, int size,
23 int dt1, int dt2, int *num_skipped)
24{
25 struct usb_descriptor_header *h;
26 int n = 0;
27 unsigned char *buffer0 = buffer;
28
29 /* Find the next descriptor of type dt1 or dt2 */
30 while (size > 0) {
31 h = (struct usb_descriptor_header *) buffer;
32 if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
33 break;
34 buffer += h->bLength;
35 size -= h->bLength;
36 ++n;
37 }
38
39 /* Store the number of descriptors skipped and return the
40 * number of bytes skipped */
41 if (num_skipped)
42 *num_skipped = n;
43 return buffer - buffer0;
44}
45
46static void usb_parse_ssp_isoc_endpoint_companion(struct device *ddev,
47 int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
48 unsigned char *buffer, int size)
49{
50 struct usb_ssp_isoc_ep_comp_descriptor *desc;
51
52 /*
53 * The SuperSpeedPlus Isoc endpoint companion descriptor immediately
54 * follows the SuperSpeed Endpoint Companion descriptor
55 */
56 desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;
57 if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||
58 size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {
59 dev_notice(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"
60 "for config %d interface %d altsetting %d ep %d.\n",
61 cfgno, inum, asnum, ep->desc.bEndpointAddress);
62 return;
63 }
64 memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);
65}
66
67static void usb_parse_eusb2_isoc_endpoint_companion(struct device *ddev,
68 int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
69 unsigned char *buffer, int size)
70{
71 struct usb_eusb2_isoc_ep_comp_descriptor *desc;
72 struct usb_descriptor_header *h;
73
74 /*
75 * eUSB2 isochronous endpoint companion descriptor for this endpoint
76 * shall be declared before the next endpoint or interface descriptor
77 */
78 while (size >= USB_DT_EUSB2_ISOC_EP_COMP_SIZE) {
79 h = (struct usb_descriptor_header *)buffer;
80
81 if (h->bDescriptorType == USB_DT_EUSB2_ISOC_ENDPOINT_COMP) {
82 desc = (struct usb_eusb2_isoc_ep_comp_descriptor *)buffer;
83 ep->eusb2_isoc_ep_comp = *desc;
84 return;
85 }
86 if (h->bDescriptorType == USB_DT_ENDPOINT ||
87 h->bDescriptorType == USB_DT_INTERFACE)
88 break;
89
90 buffer += h->bLength;
91 size -= h->bLength;
92 }
93
94 dev_notice(ddev, "No eUSB2 isoc ep %d companion for config %d interface %d altsetting %d\n",
95 ep->desc.bEndpointAddress, cfgno, inum, asnum);
96}
97
98static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
99 int inum, int asnum, struct usb_host_endpoint *ep,
100 unsigned char *buffer, int size)
101{
102 struct usb_ss_ep_comp_descriptor *desc;
103 int max_tx;
104
105 /* The SuperSpeed endpoint companion descriptor is supposed to
106 * be the first thing immediately following the endpoint descriptor.
107 */
108 desc = (struct usb_ss_ep_comp_descriptor *) buffer;
109
110 if (size < USB_DT_SS_EP_COMP_SIZE) {
111 dev_notice(ddev,
112 "invalid SuperSpeed endpoint companion descriptor "
113 "of length %d, skipping\n", size);
114 return;
115 }
116
117 if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP) {
118 dev_notice(ddev, "No SuperSpeed endpoint companion for config %d "
119 " interface %d altsetting %d ep %d: "
120 "using minimum values\n",
121 cfgno, inum, asnum, ep->desc.bEndpointAddress);
122
123 /* Fill in some default values.
124 * Leave bmAttributes as zero, which will mean no streams for
125 * bulk, and isoc won't support multiple bursts of packets.
126 * With bursts of only one packet, and a Mult of 1, the max
127 * amount of data moved per endpoint service interval is one
128 * packet.
129 */
130 ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
131 ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
132 if (usb_endpoint_xfer_isoc(epd: &ep->desc) ||
133 usb_endpoint_xfer_int(epd: &ep->desc))
134 ep->ss_ep_comp.wBytesPerInterval =
135 ep->desc.wMaxPacketSize;
136 return;
137 }
138 buffer += desc->bLength;
139 size -= desc->bLength;
140 memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
141
142 /* Check the various values */
143 if (usb_endpoint_xfer_control(epd: &ep->desc) && desc->bMaxBurst != 0) {
144 dev_notice(ddev, "Control endpoint with bMaxBurst = %d in "
145 "config %d interface %d altsetting %d ep %d: "
146 "setting to zero\n", desc->bMaxBurst,
147 cfgno, inum, asnum, ep->desc.bEndpointAddress);
148 ep->ss_ep_comp.bMaxBurst = 0;
149 } else if (desc->bMaxBurst > 15) {
150 dev_notice(ddev, "Endpoint with bMaxBurst = %d in "
151 "config %d interface %d altsetting %d ep %d: "
152 "setting to 15\n", desc->bMaxBurst,
153 cfgno, inum, asnum, ep->desc.bEndpointAddress);
154 ep->ss_ep_comp.bMaxBurst = 15;
155 }
156
157 if ((usb_endpoint_xfer_control(epd: &ep->desc) ||
158 usb_endpoint_xfer_int(epd: &ep->desc)) &&
159 desc->bmAttributes != 0) {
160 dev_notice(ddev, "%s endpoint with bmAttributes = %d in "
161 "config %d interface %d altsetting %d ep %d: "
162 "setting to zero\n",
163 usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
164 desc->bmAttributes,
165 cfgno, inum, asnum, ep->desc.bEndpointAddress);
166 ep->ss_ep_comp.bmAttributes = 0;
167 } else if (usb_endpoint_xfer_bulk(epd: &ep->desc) &&
168 desc->bmAttributes > 16) {
169 dev_notice(ddev, "Bulk endpoint with more than 65536 streams in "
170 "config %d interface %d altsetting %d ep %d: "
171 "setting to max\n",
172 cfgno, inum, asnum, ep->desc.bEndpointAddress);
173 ep->ss_ep_comp.bmAttributes = 16;
174 } else if (usb_endpoint_xfer_isoc(epd: &ep->desc) &&
175 !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
176 USB_SS_MULT(desc->bmAttributes) > 3) {
177 dev_notice(ddev, "Isoc endpoint has Mult of %d in "
178 "config %d interface %d altsetting %d ep %d: "
179 "setting to 3\n",
180 USB_SS_MULT(desc->bmAttributes),
181 cfgno, inum, asnum, ep->desc.bEndpointAddress);
182 ep->ss_ep_comp.bmAttributes = 2;
183 }
184
185 if (usb_endpoint_xfer_isoc(epd: &ep->desc))
186 max_tx = (desc->bMaxBurst + 1) *
187 (USB_SS_MULT(desc->bmAttributes)) *
188 usb_endpoint_maxp(epd: &ep->desc);
189 else if (usb_endpoint_xfer_int(epd: &ep->desc))
190 max_tx = usb_endpoint_maxp(epd: &ep->desc) *
191 (desc->bMaxBurst + 1);
192 else
193 max_tx = 999999;
194 if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
195 dev_notice(ddev, "%s endpoint with wBytesPerInterval of %d in "
196 "config %d interface %d altsetting %d ep %d: "
197 "setting to %d\n",
198 usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
199 le16_to_cpu(desc->wBytesPerInterval),
200 cfgno, inum, asnum, ep->desc.bEndpointAddress,
201 max_tx);
202 ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
203 }
204 /* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
205 if (usb_endpoint_xfer_isoc(epd: &ep->desc) &&
206 USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
207 usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
208 ep, buffer, size);
209}
210
211static const unsigned short low_speed_maxpacket_maxes[4] = {
212 [USB_ENDPOINT_XFER_CONTROL] = 8,
213 [USB_ENDPOINT_XFER_ISOC] = 0,
214 [USB_ENDPOINT_XFER_BULK] = 0,
215 [USB_ENDPOINT_XFER_INT] = 8,
216};
217static const unsigned short full_speed_maxpacket_maxes[4] = {
218 [USB_ENDPOINT_XFER_CONTROL] = 64,
219 [USB_ENDPOINT_XFER_ISOC] = 1023,
220 [USB_ENDPOINT_XFER_BULK] = 64,
221 [USB_ENDPOINT_XFER_INT] = 64,
222};
223static const unsigned short high_speed_maxpacket_maxes[4] = {
224 [USB_ENDPOINT_XFER_CONTROL] = 64,
225 [USB_ENDPOINT_XFER_ISOC] = 1024,
226
227 /* Bulk should be 512, but some devices use 1024: we will warn below */
228 [USB_ENDPOINT_XFER_BULK] = 1024,
229 [USB_ENDPOINT_XFER_INT] = 1024,
230};
231static const unsigned short super_speed_maxpacket_maxes[4] = {
232 [USB_ENDPOINT_XFER_CONTROL] = 512,
233 [USB_ENDPOINT_XFER_ISOC] = 1024,
234 [USB_ENDPOINT_XFER_BULK] = 1024,
235 [USB_ENDPOINT_XFER_INT] = 1024,
236};
237
238static bool endpoint_is_duplicate(struct usb_endpoint_descriptor *e1,
239 struct usb_endpoint_descriptor *e2)
240{
241 if (e1->bEndpointAddress == e2->bEndpointAddress)
242 return true;
243
244 if (usb_endpoint_xfer_control(epd: e1) || usb_endpoint_xfer_control(epd: e2)) {
245 if (usb_endpoint_num(epd: e1) == usb_endpoint_num(epd: e2))
246 return true;
247 }
248
249 return false;
250}
251
252/*
253 * Check for duplicate endpoint addresses in other interfaces and in the
254 * altsetting currently being parsed.
255 */
256static bool config_endpoint_is_duplicate(struct usb_host_config *config,
257 int inum, int asnum, struct usb_endpoint_descriptor *d)
258{
259 struct usb_endpoint_descriptor *epd;
260 struct usb_interface_cache *intfc;
261 struct usb_host_interface *alt;
262 int i, j, k;
263
264 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
265 intfc = config->intf_cache[i];
266
267 for (j = 0; j < intfc->num_altsetting; ++j) {
268 alt = &intfc->altsetting[j];
269
270 if (alt->desc.bInterfaceNumber == inum &&
271 alt->desc.bAlternateSetting != asnum)
272 continue;
273
274 for (k = 0; k < alt->desc.bNumEndpoints; ++k) {
275 epd = &alt->endpoint[k].desc;
276
277 if (endpoint_is_duplicate(e1: epd, e2: d))
278 return true;
279 }
280 }
281 }
282
283 return false;
284}
285
286static int usb_parse_endpoint(struct device *ddev, int cfgno,
287 struct usb_host_config *config, int inum, int asnum,
288 struct usb_host_interface *ifp, int num_ep,
289 unsigned char *buffer, int size)
290{
291 struct usb_device *udev = to_usb_device(ddev);
292 unsigned char *buffer0 = buffer;
293 struct usb_endpoint_descriptor *d;
294 struct usb_host_endpoint *endpoint;
295 int n, i, j, retval;
296 unsigned int maxp;
297 const unsigned short *maxpacket_maxes;
298 u16 bcdUSB;
299
300 d = (struct usb_endpoint_descriptor *) buffer;
301 bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
302 buffer += d->bLength;
303 size -= d->bLength;
304
305 if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
306 n = USB_DT_ENDPOINT_AUDIO_SIZE;
307 else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
308 n = USB_DT_ENDPOINT_SIZE;
309 else {
310 dev_notice(ddev, "config %d interface %d altsetting %d has an "
311 "invalid endpoint descriptor of length %d, skipping\n",
312 cfgno, inum, asnum, d->bLength);
313 goto skip_to_next_endpoint_or_interface_descriptor;
314 }
315
316 i = usb_endpoint_num(epd: d);
317 if (i == 0) {
318 dev_notice(ddev, "config %d interface %d altsetting %d has an "
319 "invalid descriptor for endpoint zero, skipping\n",
320 cfgno, inum, asnum);
321 goto skip_to_next_endpoint_or_interface_descriptor;
322 }
323
324 /* Only store as many endpoints as we have room for */
325 if (ifp->desc.bNumEndpoints >= num_ep)
326 goto skip_to_next_endpoint_or_interface_descriptor;
327
328 /* Save a copy of the descriptor and use it instead of the original */
329 endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
330 memcpy(&endpoint->desc, d, n);
331 d = &endpoint->desc;
332
333 /* Clear the reserved bits in bEndpointAddress */
334 i = d->bEndpointAddress &
335 (USB_ENDPOINT_DIR_MASK | USB_ENDPOINT_NUMBER_MASK);
336 if (i != d->bEndpointAddress) {
337 dev_notice(ddev, "config %d interface %d altsetting %d has an endpoint descriptor with address 0x%X, changing to 0x%X\n",
338 cfgno, inum, asnum, d->bEndpointAddress, i);
339 endpoint->desc.bEndpointAddress = i;
340 }
341
342 /* Check for duplicate endpoint addresses */
343 if (config_endpoint_is_duplicate(config, inum, asnum, d)) {
344 dev_notice(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
345 cfgno, inum, asnum, d->bEndpointAddress);
346 goto skip_to_next_endpoint_or_interface_descriptor;
347 }
348
349 /* Ignore some endpoints */
350 if (udev->quirks & USB_QUIRK_ENDPOINT_IGNORE) {
351 if (usb_endpoint_is_ignored(udev, intf: ifp, epd: d)) {
352 dev_notice(ddev, "config %d interface %d altsetting %d has an ignored endpoint with address 0x%X, skipping\n",
353 cfgno, inum, asnum,
354 d->bEndpointAddress);
355 goto skip_to_next_endpoint_or_interface_descriptor;
356 }
357 }
358
359 /* Accept this endpoint */
360 ++ifp->desc.bNumEndpoints;
361 INIT_LIST_HEAD(list: &endpoint->urb_list);
362
363 /*
364 * Fix up bInterval values outside the legal range.
365 * Use 10 or 8 ms if no proper value can be guessed.
366 */
367 i = 0; /* i = min, j = max, n = default */
368 j = 255;
369 if (usb_endpoint_xfer_int(epd: d)) {
370 i = 1;
371 switch (udev->speed) {
372 case USB_SPEED_SUPER_PLUS:
373 case USB_SPEED_SUPER:
374 case USB_SPEED_HIGH:
375 /*
376 * Many device manufacturers are using full-speed
377 * bInterval values in high-speed interrupt endpoint
378 * descriptors. Try to fix those and fall back to an
379 * 8-ms default value otherwise.
380 */
381 n = fls(x: d->bInterval*8);
382 if (n == 0)
383 n = 7; /* 8 ms = 2^(7-1) uframes */
384 j = 16;
385
386 /*
387 * Adjust bInterval for quirked devices.
388 */
389 /*
390 * This quirk fixes bIntervals reported in ms.
391 */
392 if (udev->quirks & USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
393 n = clamp(fls(d->bInterval) + 3, i, j);
394 i = j = n;
395 }
396 /*
397 * This quirk fixes bIntervals reported in
398 * linear microframes.
399 */
400 if (udev->quirks & USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
401 n = clamp(fls(d->bInterval), i, j);
402 i = j = n;
403 }
404 break;
405 default: /* USB_SPEED_FULL or _LOW */
406 /*
407 * For low-speed, 10 ms is the official minimum.
408 * But some "overclocked" devices might want faster
409 * polling so we'll allow it.
410 */
411 n = 10;
412 break;
413 }
414 } else if (usb_endpoint_xfer_isoc(epd: d)) {
415 i = 1;
416 j = 16;
417 switch (udev->speed) {
418 case USB_SPEED_HIGH:
419 n = 7; /* 8 ms = 2^(7-1) uframes */
420 break;
421 default: /* USB_SPEED_FULL */
422 n = 4; /* 8 ms = 2^(4-1) frames */
423 break;
424 }
425 }
426 if (d->bInterval < i || d->bInterval > j) {
427 dev_notice(ddev, "config %d interface %d altsetting %d "
428 "endpoint 0x%X has an invalid bInterval %d, "
429 "changing to %d\n",
430 cfgno, inum, asnum,
431 d->bEndpointAddress, d->bInterval, n);
432 endpoint->desc.bInterval = n;
433 }
434
435 /* Some buggy low-speed devices have Bulk endpoints, which is
436 * explicitly forbidden by the USB spec. In an attempt to make
437 * them usable, we will try treating them as Interrupt endpoints.
438 */
439 if (udev->speed == USB_SPEED_LOW && usb_endpoint_xfer_bulk(epd: d)) {
440 dev_notice(ddev, "config %d interface %d altsetting %d "
441 "endpoint 0x%X is Bulk; changing to Interrupt\n",
442 cfgno, inum, asnum, d->bEndpointAddress);
443 endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
444 endpoint->desc.bInterval = 1;
445 if (usb_endpoint_maxp(epd: &endpoint->desc) > 8)
446 endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
447 }
448
449 /*
450 * Validate the wMaxPacketSize field.
451 * eUSB2 devices (see USB 2.0 Double Isochronous IN ECN 9.6.6 Endpoint)
452 * and devices with isochronous endpoints in altsetting 0 (see USB 2.0
453 * end of section 5.6.3) have wMaxPacketSize = 0.
454 * So don't warn about those.
455 */
456 maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize);
457
458 if (maxp == 0 && bcdUSB != 0x0220 &&
459 !(usb_endpoint_xfer_isoc(epd: d) && asnum == 0))
460 dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
461 cfgno, inum, asnum, d->bEndpointAddress);
462
463 /* Find the highest legal maxpacket size for this endpoint */
464 i = 0; /* additional transactions per microframe */
465 switch (udev->speed) {
466 case USB_SPEED_LOW:
467 maxpacket_maxes = low_speed_maxpacket_maxes;
468 break;
469 case USB_SPEED_FULL:
470 maxpacket_maxes = full_speed_maxpacket_maxes;
471 break;
472 case USB_SPEED_HIGH:
473 /* Multiple-transactions bits are allowed only for HS periodic endpoints */
474 if (usb_endpoint_xfer_int(epd: d) || usb_endpoint_xfer_isoc(epd: d)) {
475 i = maxp & USB_EP_MAXP_MULT_MASK;
476 maxp &= ~i;
477 }
478 fallthrough;
479 default:
480 maxpacket_maxes = high_speed_maxpacket_maxes;
481 break;
482 case USB_SPEED_SUPER:
483 case USB_SPEED_SUPER_PLUS:
484 maxpacket_maxes = super_speed_maxpacket_maxes;
485 break;
486 }
487 j = maxpacket_maxes[usb_endpoint_type(epd: &endpoint->desc)];
488
489 if (maxp > j) {
490 dev_notice(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
491 cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
492 maxp = j;
493 endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
494 }
495
496 /*
497 * Some buggy high speed devices have bulk endpoints using
498 * maxpacket sizes other than 512. High speed HCDs may not
499 * be able to handle that particular bug, so let's warn...
500 */
501 if (udev->speed == USB_SPEED_HIGH && usb_endpoint_xfer_bulk(epd: d)) {
502 if (maxp != 512)
503 dev_notice(ddev, "config %d interface %d altsetting %d "
504 "bulk endpoint 0x%X has invalid maxpacket %d\n",
505 cfgno, inum, asnum, d->bEndpointAddress,
506 maxp);
507 }
508
509 /* Parse a possible eUSB2 periodic endpoint companion descriptor */
510 if (udev->speed == USB_SPEED_HIGH && bcdUSB == 0x0220 &&
511 !le16_to_cpu(d->wMaxPacketSize) && usb_endpoint_is_isoc_in(epd: d))
512 usb_parse_eusb2_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
513 ep: endpoint, buffer, size);
514
515 /* Parse a possible SuperSpeed endpoint companion descriptor */
516 if (udev->speed >= USB_SPEED_SUPER)
517 usb_parse_ss_endpoint_companion(ddev, cfgno,
518 inum, asnum, ep: endpoint, buffer, size);
519
520 /* Skip over any Class Specific or Vendor Specific descriptors;
521 * find the next endpoint or interface descriptor */
522 endpoint->extra = buffer;
523 i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
524 USB_DT_INTERFACE, num_skipped: &n);
525 endpoint->extralen = i;
526 retval = buffer - buffer0 + i;
527 if (n > 0)
528 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
529 n, str_plural(n), "endpoint");
530 return retval;
531
532skip_to_next_endpoint_or_interface_descriptor:
533 i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
534 USB_DT_INTERFACE, NULL);
535 return buffer - buffer0 + i;
536}
537
538void usb_release_interface_cache(struct kref *ref)
539{
540 struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
541 int j;
542
543 for (j = 0; j < intfc->num_altsetting; j++) {
544 struct usb_host_interface *alt = &intfc->altsetting[j];
545
546 kfree(objp: alt->endpoint);
547 kfree(objp: alt->string);
548 }
549 kfree(objp: intfc);
550}
551
552static int usb_parse_interface(struct device *ddev, int cfgno,
553 struct usb_host_config *config, unsigned char *buffer, int size,
554 u8 inums[], u8 nalts[])
555{
556 unsigned char *buffer0 = buffer;
557 struct usb_interface_descriptor *d;
558 int inum, asnum;
559 struct usb_interface_cache *intfc;
560 struct usb_host_interface *alt;
561 int i, n;
562 int len, retval;
563 int num_ep, num_ep_orig;
564
565 d = (struct usb_interface_descriptor *) buffer;
566 buffer += d->bLength;
567 size -= d->bLength;
568
569 if (d->bLength < USB_DT_INTERFACE_SIZE)
570 goto skip_to_next_interface_descriptor;
571
572 /* Which interface entry is this? */
573 intfc = NULL;
574 inum = d->bInterfaceNumber;
575 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
576 if (inums[i] == inum) {
577 intfc = config->intf_cache[i];
578 break;
579 }
580 }
581 if (!intfc || intfc->num_altsetting >= nalts[i])
582 goto skip_to_next_interface_descriptor;
583
584 /* Check for duplicate altsetting entries */
585 asnum = d->bAlternateSetting;
586 for ((i = 0, alt = &intfc->altsetting[0]);
587 i < intfc->num_altsetting;
588 (++i, ++alt)) {
589 if (alt->desc.bAlternateSetting == asnum) {
590 dev_notice(ddev, "Duplicate descriptor for config %d "
591 "interface %d altsetting %d, skipping\n",
592 cfgno, inum, asnum);
593 goto skip_to_next_interface_descriptor;
594 }
595 }
596
597 ++intfc->num_altsetting;
598 memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
599
600 /* Skip over any Class Specific or Vendor Specific descriptors;
601 * find the first endpoint or interface descriptor */
602 alt->extra = buffer;
603 i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
604 USB_DT_INTERFACE, num_skipped: &n);
605 alt->extralen = i;
606 if (n > 0)
607 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
608 n, str_plural(n), "interface");
609 buffer += i;
610 size -= i;
611
612 /* Allocate space for the right(?) number of endpoints */
613 num_ep = num_ep_orig = alt->desc.bNumEndpoints;
614 alt->desc.bNumEndpoints = 0; /* Use as a counter */
615 if (num_ep > USB_MAXENDPOINTS) {
616 dev_notice(ddev, "too many endpoints for config %d interface %d "
617 "altsetting %d: %d, using maximum allowed: %d\n",
618 cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
619 num_ep = USB_MAXENDPOINTS;
620 }
621
622 if (num_ep > 0) {
623 /* Can't allocate 0 bytes */
624 len = sizeof(struct usb_host_endpoint) * num_ep;
625 alt->endpoint = kzalloc(len, GFP_KERNEL);
626 if (!alt->endpoint)
627 return -ENOMEM;
628 }
629
630 /* Parse all the endpoint descriptors */
631 n = 0;
632 while (size > 0) {
633 if (((struct usb_descriptor_header *) buffer)->bDescriptorType
634 == USB_DT_INTERFACE)
635 break;
636 retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
637 ifp: alt, num_ep, buffer, size);
638 if (retval < 0)
639 return retval;
640 ++n;
641
642 buffer += retval;
643 size -= retval;
644 }
645
646 if (n != num_ep_orig)
647 dev_notice(ddev, "config %d interface %d altsetting %d has %d "
648 "endpoint descriptor%s, different from the interface "
649 "descriptor's value: %d\n",
650 cfgno, inum, asnum, n, str_plural(n), num_ep_orig);
651 return buffer - buffer0;
652
653skip_to_next_interface_descriptor:
654 i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
655 USB_DT_INTERFACE, NULL);
656 return buffer - buffer0 + i;
657}
658
659static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
660 struct usb_host_config *config, unsigned char *buffer, int size)
661{
662 struct device *ddev = &dev->dev;
663 unsigned char *buffer0 = buffer;
664 int cfgno;
665 int nintf, nintf_orig;
666 int i, j, n;
667 struct usb_interface_cache *intfc;
668 unsigned char *buffer2;
669 int size2;
670 struct usb_descriptor_header *header;
671 int retval;
672 u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
673 unsigned iad_num = 0;
674
675 memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
676 nintf = nintf_orig = config->desc.bNumInterfaces;
677 config->desc.bNumInterfaces = 0; // Adjusted later
678
679 if (config->desc.bDescriptorType != USB_DT_CONFIG ||
680 config->desc.bLength < USB_DT_CONFIG_SIZE ||
681 config->desc.bLength > size) {
682 dev_notice(ddev, "invalid descriptor for config index %d: "
683 "type = 0x%X, length = %d\n", cfgidx,
684 config->desc.bDescriptorType, config->desc.bLength);
685 return -EINVAL;
686 }
687 cfgno = config->desc.bConfigurationValue;
688
689 buffer += config->desc.bLength;
690 size -= config->desc.bLength;
691
692 if (nintf > USB_MAXINTERFACES) {
693 dev_notice(ddev, "config %d has too many interfaces: %d, "
694 "using maximum allowed: %d\n",
695 cfgno, nintf, USB_MAXINTERFACES);
696 nintf = USB_MAXINTERFACES;
697 }
698
699 /* Go through the descriptors, checking their length and counting the
700 * number of altsettings for each interface */
701 n = 0;
702 for ((buffer2 = buffer, size2 = size);
703 size2 > 0;
704 (buffer2 += header->bLength, size2 -= header->bLength)) {
705
706 if (size2 < sizeof(struct usb_descriptor_header)) {
707 dev_notice(ddev, "config %d descriptor has %d excess "
708 "byte%s, ignoring\n",
709 cfgno, size2, str_plural(size2));
710 break;
711 }
712
713 header = (struct usb_descriptor_header *) buffer2;
714 if ((header->bLength > size2) || (header->bLength < 2)) {
715 dev_notice(ddev, "config %d has an invalid descriptor "
716 "of length %d, skipping remainder of the config\n",
717 cfgno, header->bLength);
718 break;
719 }
720
721 if (header->bDescriptorType == USB_DT_INTERFACE) {
722 struct usb_interface_descriptor *d;
723 int inum;
724
725 d = (struct usb_interface_descriptor *) header;
726 if (d->bLength < USB_DT_INTERFACE_SIZE) {
727 dev_notice(ddev, "config %d has an invalid "
728 "interface descriptor of length %d, "
729 "skipping\n", cfgno, d->bLength);
730 continue;
731 }
732
733 inum = d->bInterfaceNumber;
734
735 if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
736 n >= nintf_orig) {
737 dev_notice(ddev, "config %d has more interface "
738 "descriptors, than it declares in "
739 "bNumInterfaces, ignoring interface "
740 "number: %d\n", cfgno, inum);
741 continue;
742 }
743
744 if (inum >= nintf_orig)
745 dev_notice(ddev, "config %d has an invalid "
746 "interface number: %d but max is %d\n",
747 cfgno, inum, nintf_orig - 1);
748
749 /* Have we already encountered this interface?
750 * Count its altsettings */
751 for (i = 0; i < n; ++i) {
752 if (inums[i] == inum)
753 break;
754 }
755 if (i < n) {
756 if (nalts[i] < 255)
757 ++nalts[i];
758 } else if (n < USB_MAXINTERFACES) {
759 inums[n] = inum;
760 nalts[n] = 1;
761 ++n;
762 }
763
764 } else if (header->bDescriptorType ==
765 USB_DT_INTERFACE_ASSOCIATION) {
766 struct usb_interface_assoc_descriptor *d;
767
768 d = (struct usb_interface_assoc_descriptor *)header;
769 if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
770 dev_notice(ddev,
771 "config %d has an invalid interface association descriptor of length %d, skipping\n",
772 cfgno, d->bLength);
773 continue;
774 }
775
776 if (iad_num == USB_MAXIADS) {
777 dev_notice(ddev, "found more Interface "
778 "Association Descriptors "
779 "than allocated for in "
780 "configuration %d\n", cfgno);
781 } else {
782 config->intf_assoc[iad_num] = d;
783 iad_num++;
784 }
785
786 } else if (header->bDescriptorType == USB_DT_DEVICE ||
787 header->bDescriptorType == USB_DT_CONFIG)
788 dev_notice(ddev, "config %d contains an unexpected "
789 "descriptor of type 0x%X, skipping\n",
790 cfgno, header->bDescriptorType);
791
792 } /* for ((buffer2 = buffer, size2 = size); ...) */
793 size = buffer2 - buffer;
794 config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
795
796 if (n != nintf)
797 dev_notice(ddev, "config %d has %d interface%s, different from "
798 "the descriptor's value: %d\n",
799 cfgno, n, str_plural(n), nintf_orig);
800 else if (n == 0)
801 dev_notice(ddev, "config %d has no interfaces?\n", cfgno);
802 config->desc.bNumInterfaces = nintf = n;
803
804 /* Check for missing interface numbers */
805 for (i = 0; i < nintf; ++i) {
806 for (j = 0; j < nintf; ++j) {
807 if (inums[j] == i)
808 break;
809 }
810 if (j >= nintf)
811 dev_notice(ddev, "config %d has no interface number "
812 "%d\n", cfgno, i);
813 }
814
815 /* Allocate the usb_interface_caches and altsetting arrays */
816 for (i = 0; i < nintf; ++i) {
817 j = nalts[i];
818 if (j > USB_MAXALTSETTING) {
819 dev_notice(ddev, "too many alternate settings for "
820 "config %d interface %d: %d, "
821 "using maximum allowed: %d\n",
822 cfgno, inums[i], j, USB_MAXALTSETTING);
823 nalts[i] = j = USB_MAXALTSETTING;
824 }
825
826 intfc = kzalloc(struct_size(intfc, altsetting, j), GFP_KERNEL);
827 config->intf_cache[i] = intfc;
828 if (!intfc)
829 return -ENOMEM;
830 kref_init(kref: &intfc->ref);
831 }
832
833 /* FIXME: parse the BOS descriptor */
834
835 /* Skip over any Class Specific or Vendor Specific descriptors;
836 * find the first interface descriptor */
837 config->extra = buffer;
838 i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
839 USB_DT_INTERFACE, num_skipped: &n);
840 config->extralen = i;
841 if (n > 0)
842 dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
843 n, str_plural(n), "configuration");
844 buffer += i;
845 size -= i;
846
847 /* Parse all the interface/altsetting descriptors */
848 while (size > 0) {
849 retval = usb_parse_interface(ddev, cfgno, config,
850 buffer, size, inums, nalts);
851 if (retval < 0)
852 return retval;
853
854 buffer += retval;
855 size -= retval;
856 }
857
858 /* Check for missing altsettings */
859 for (i = 0; i < nintf; ++i) {
860 intfc = config->intf_cache[i];
861 for (j = 0; j < intfc->num_altsetting; ++j) {
862 for (n = 0; n < intfc->num_altsetting; ++n) {
863 if (intfc->altsetting[n].desc.
864 bAlternateSetting == j)
865 break;
866 }
867 if (n >= intfc->num_altsetting)
868 dev_notice(ddev, "config %d interface %d has no "
869 "altsetting %d\n", cfgno, inums[i], j);
870 }
871 }
872
873 return 0;
874}
875
876/* hub-only!! ... and only exported for reset/reinit path.
877 * otherwise used internally on disconnect/destroy path
878 */
879void usb_destroy_configuration(struct usb_device *dev)
880{
881 int c, i;
882
883 if (!dev->config)
884 return;
885
886 if (dev->rawdescriptors) {
887 for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
888 kfree(objp: dev->rawdescriptors[i]);
889
890 kfree(objp: dev->rawdescriptors);
891 dev->rawdescriptors = NULL;
892 }
893
894 for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
895 struct usb_host_config *cf = &dev->config[c];
896
897 kfree(objp: cf->string);
898 for (i = 0; i < cf->desc.bNumInterfaces; i++) {
899 if (cf->intf_cache[i])
900 kref_put(kref: &cf->intf_cache[i]->ref,
901 release: usb_release_interface_cache);
902 }
903 }
904 kfree(objp: dev->config);
905 dev->config = NULL;
906}
907
908
909/*
910 * Get the USB config descriptors, cache and parse'em
911 *
912 * hub-only!! ... and only in reset path, or usb_new_device()
913 * (used by real hubs and virtual root hubs)
914 */
915int usb_get_configuration(struct usb_device *dev)
916{
917 struct device *ddev = &dev->dev;
918 int ncfg = dev->descriptor.bNumConfigurations;
919 unsigned int cfgno, length;
920 unsigned char *bigbuffer;
921 struct usb_config_descriptor *desc;
922 int result;
923
924 if (ncfg > USB_MAXCONFIG) {
925 dev_notice(ddev, "too many configurations: %d, "
926 "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
927 dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
928 }
929
930 if (ncfg < 1) {
931 dev_err(ddev, "no configurations\n");
932 return -EINVAL;
933 }
934
935 length = ncfg * sizeof(struct usb_host_config);
936 dev->config = kzalloc(length, GFP_KERNEL);
937 if (!dev->config)
938 return -ENOMEM;
939
940 length = ncfg * sizeof(char *);
941 dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
942 if (!dev->rawdescriptors)
943 return -ENOMEM;
944
945 desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
946 if (!desc)
947 return -ENOMEM;
948
949 for (cfgno = 0; cfgno < ncfg; cfgno++) {
950 /* We grab just the first descriptor so we know how long
951 * the whole configuration is */
952 result = usb_get_descriptor(dev, USB_DT_CONFIG, descindex: cfgno,
953 buf: desc, USB_DT_CONFIG_SIZE);
954 if (result < 0) {
955 dev_err(ddev, "unable to read config index %d "
956 "descriptor/%s: %d\n", cfgno, "start", result);
957 if (result != -EPIPE)
958 goto err;
959 dev_notice(ddev, "chopping to %d config(s)\n", cfgno);
960 dev->descriptor.bNumConfigurations = cfgno;
961 break;
962 } else if (result < 4) {
963 dev_err(ddev, "config index %d descriptor too short "
964 "(expected %i, got %i)\n", cfgno,
965 USB_DT_CONFIG_SIZE, result);
966 result = -EINVAL;
967 goto err;
968 }
969 length = max_t(int, le16_to_cpu(desc->wTotalLength),
970 USB_DT_CONFIG_SIZE);
971
972 /* Now that we know the length, get the whole thing */
973 bigbuffer = kmalloc(length, GFP_KERNEL);
974 if (!bigbuffer) {
975 result = -ENOMEM;
976 goto err;
977 }
978
979 if (dev->quirks & USB_QUIRK_DELAY_INIT)
980 msleep(msecs: 200);
981
982 result = usb_get_descriptor(dev, USB_DT_CONFIG, descindex: cfgno,
983 buf: bigbuffer, size: length);
984 if (result < 0) {
985 dev_err(ddev, "unable to read config index %d "
986 "descriptor/%s\n", cfgno, "all");
987 kfree(objp: bigbuffer);
988 goto err;
989 }
990 if (result < length) {
991 dev_notice(ddev, "config index %d descriptor too short "
992 "(expected %i, got %i)\n", cfgno, length, result);
993 length = result;
994 }
995
996 dev->rawdescriptors[cfgno] = bigbuffer;
997
998 result = usb_parse_configuration(dev, cfgidx: cfgno,
999 config: &dev->config[cfgno], buffer: bigbuffer, size: length);
1000 if (result < 0) {
1001 ++cfgno;
1002 goto err;
1003 }
1004 }
1005
1006err:
1007 kfree(objp: desc);
1008 dev->descriptor.bNumConfigurations = cfgno;
1009
1010 return result;
1011}
1012
1013void usb_release_bos_descriptor(struct usb_device *dev)
1014{
1015 if (dev->bos) {
1016 kfree(objp: dev->bos->desc);
1017 kfree(objp: dev->bos);
1018 dev->bos = NULL;
1019 }
1020}
1021
1022static const __u8 bos_desc_len[256] = {
1023 [USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
1024 [USB_CAP_TYPE_EXT] = USB_DT_USB_EXT_CAP_SIZE,
1025 [USB_SS_CAP_TYPE] = USB_DT_USB_SS_CAP_SIZE,
1026 [USB_SSP_CAP_TYPE] = USB_DT_USB_SSP_CAP_SIZE(1),
1027 [CONTAINER_ID_TYPE] = USB_DT_USB_SS_CONTN_ID_SIZE,
1028 [USB_PTM_CAP_TYPE] = USB_DT_USB_PTM_ID_SIZE,
1029};
1030
1031/* Get BOS descriptor set */
1032int usb_get_bos_descriptor(struct usb_device *dev)
1033{
1034 struct device *ddev = &dev->dev;
1035 struct usb_bos_descriptor *bos;
1036 struct usb_dev_cap_header *cap;
1037 struct usb_ssp_cap_descriptor *ssp_cap;
1038 unsigned char *buffer, *buffer0;
1039 int length, total_len, num, i, ssac;
1040 __u8 cap_type;
1041 int ret;
1042
1043 if (dev->quirks & USB_QUIRK_NO_BOS) {
1044 dev_dbg(ddev, "skipping BOS descriptor\n");
1045 return -ENOMSG;
1046 }
1047
1048 bos = kzalloc(sizeof(*bos), GFP_KERNEL);
1049 if (!bos)
1050 return -ENOMEM;
1051
1052 /* Get BOS descriptor */
1053 ret = usb_get_descriptor(dev, USB_DT_BOS, descindex: 0, buf: bos, USB_DT_BOS_SIZE);
1054 if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) {
1055 dev_notice(ddev, "unable to get BOS descriptor or descriptor too short\n");
1056 if (ret >= 0)
1057 ret = -ENOMSG;
1058 kfree(objp: bos);
1059 return ret;
1060 }
1061
1062 length = bos->bLength;
1063 total_len = le16_to_cpu(bos->wTotalLength);
1064 num = bos->bNumDeviceCaps;
1065 kfree(objp: bos);
1066 if (total_len < length)
1067 return -EINVAL;
1068
1069 dev->bos = kzalloc(sizeof(*dev->bos), GFP_KERNEL);
1070 if (!dev->bos)
1071 return -ENOMEM;
1072
1073 /* Now let's get the whole BOS descriptor set */
1074 buffer = kzalloc(total_len, GFP_KERNEL);
1075 if (!buffer) {
1076 ret = -ENOMEM;
1077 goto err;
1078 }
1079 dev->bos->desc = (struct usb_bos_descriptor *)buffer;
1080
1081 ret = usb_get_descriptor(dev, USB_DT_BOS, descindex: 0, buf: buffer, size: total_len);
1082 if (ret < total_len) {
1083 dev_notice(ddev, "unable to get BOS descriptor set\n");
1084 if (ret >= 0)
1085 ret = -ENOMSG;
1086 goto err;
1087 }
1088
1089 buffer0 = buffer;
1090 total_len -= length;
1091 buffer += length;
1092
1093 for (i = 0; i < num; i++) {
1094 cap = (struct usb_dev_cap_header *)buffer;
1095
1096 if (total_len < sizeof(*cap) || total_len < cap->bLength) {
1097 dev->bos->desc->bNumDeviceCaps = i;
1098 break;
1099 }
1100 cap_type = cap->bDevCapabilityType;
1101 length = cap->bLength;
1102 if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
1103 dev->bos->desc->bNumDeviceCaps = i;
1104 break;
1105 }
1106
1107 if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
1108 dev_notice(ddev, "descriptor type invalid, skip\n");
1109 goto skip_to_next_descriptor;
1110 }
1111
1112 switch (cap_type) {
1113 case USB_CAP_TYPE_EXT:
1114 dev->bos->ext_cap =
1115 (struct usb_ext_cap_descriptor *)buffer;
1116 break;
1117 case USB_SS_CAP_TYPE:
1118 dev->bos->ss_cap =
1119 (struct usb_ss_cap_descriptor *)buffer;
1120 break;
1121 case USB_SSP_CAP_TYPE:
1122 ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
1123 ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
1124 USB_SSP_SUBLINK_SPEED_ATTRIBS);
1125 if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
1126 dev->bos->ssp_cap = ssp_cap;
1127 break;
1128 case CONTAINER_ID_TYPE:
1129 dev->bos->ss_id =
1130 (struct usb_ss_container_id_descriptor *)buffer;
1131 break;
1132 case USB_PTM_CAP_TYPE:
1133 dev->bos->ptm_cap =
1134 (struct usb_ptm_cap_descriptor *)buffer;
1135 break;
1136 default:
1137 break;
1138 }
1139
1140skip_to_next_descriptor:
1141 total_len -= length;
1142 buffer += length;
1143 }
1144 dev->bos->desc->wTotalLength = cpu_to_le16(buffer - buffer0);
1145
1146 return 0;
1147
1148err:
1149 usb_release_bos_descriptor(dev);
1150 return ret;
1151}
1152

source code of linux/drivers/usb/core/config.c