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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Clock domain and sample rate management functions
4 */
5
6#include <linux/bitops.h>
7#include <linux/init.h>
8#include <linux/string.h>
9#include <linux/usb.h>
10#include <linux/usb/audio.h>
11#include <linux/usb/audio-v2.h>
12#include <linux/usb/audio-v3.h>
13
14#include <sound/core.h>
15#include <sound/info.h>
16#include <sound/pcm.h>
17
18#include "usbaudio.h"
19#include "card.h"
20#include "helper.h"
21#include "clock.h"
22#include "quirks.h"
23
24static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
25 bool (*validator)(void *, int), u8 type)
26{
27 void *cs = NULL;
28
29 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
30 cs, type))) {
31 if (validator(cs, id))
32 return cs;
33 }
34
35 return NULL;
36}
37
38static bool validate_clock_source_v2(void *p, int id)
39{
40 struct uac_clock_source_descriptor *cs = p;
41 return cs->bClockID == id;
42}
43
44static bool validate_clock_source_v3(void *p, int id)
45{
46 struct uac3_clock_source_descriptor *cs = p;
47 return cs->bClockID == id;
48}
49
50static bool validate_clock_selector_v2(void *p, int id)
51{
52 struct uac_clock_selector_descriptor *cs = p;
53 return cs->bClockID == id;
54}
55
56static bool validate_clock_selector_v3(void *p, int id)
57{
58 struct uac3_clock_selector_descriptor *cs = p;
59 return cs->bClockID == id;
60}
61
62static bool validate_clock_multiplier_v2(void *p, int id)
63{
64 struct uac_clock_multiplier_descriptor *cs = p;
65 return cs->bClockID == id;
66}
67
68static bool validate_clock_multiplier_v3(void *p, int id)
69{
70 struct uac3_clock_multiplier_descriptor *cs = p;
71 return cs->bClockID == id;
72}
73
74#define DEFINE_FIND_HELPER(name, obj, validator, type) \
75static obj *name(struct usb_host_interface *iface, int id) \
76{ \
77 return find_uac_clock_desc(iface, id, validator, type); \
78}
79
80DEFINE_FIND_HELPER(snd_usb_find_clock_source,
81 struct uac_clock_source_descriptor,
82 validate_clock_source_v2, UAC2_CLOCK_SOURCE);
83DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
84 struct uac3_clock_source_descriptor,
85 validate_clock_source_v3, UAC3_CLOCK_SOURCE);
86
87DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
88 struct uac_clock_selector_descriptor,
89 validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
90DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
91 struct uac3_clock_selector_descriptor,
92 validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
93
94DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
95 struct uac_clock_multiplier_descriptor,
96 validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
97DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
98 struct uac3_clock_multiplier_descriptor,
99 validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
100
101static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
102{
103 unsigned char buf;
104 int ret;
105
106 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
107 UAC2_CS_CUR,
108 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
109 UAC2_CX_CLOCK_SELECTOR << 8,
110 snd_usb_ctrl_intf(chip) | (selector_id << 8),
111 &buf, sizeof(buf));
112
113 if (ret < 0)
114 return ret;
115
116 return buf;
117}
118
119static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
120 unsigned char pin)
121{
122 int ret;
123
124 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
125 UAC2_CS_CUR,
126 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
127 UAC2_CX_CLOCK_SELECTOR << 8,
128 snd_usb_ctrl_intf(chip) | (selector_id << 8),
129 &pin, sizeof(pin));
130 if (ret < 0)
131 return ret;
132
133 if (ret != sizeof(pin)) {
134 usb_audio_err(chip,
135 "setting selector (id %d) unexpected length %d\n",
136 selector_id, ret);
137 return -EINVAL;
138 }
139
140 ret = uac_clock_selector_get_val(chip, selector_id);
141 if (ret < 0)
142 return ret;
143
144 if (ret != pin) {
145 usb_audio_err(chip,
146 "setting selector (id %d) to %x failed (current: %d)\n",
147 selector_id, pin, ret);
148 return -EINVAL;
149 }
150
151 return ret;
152}
153
154static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
155 struct audioformat *fmt,
156 int source_id)
157{
158 bool ret = false;
159 int count;
160 unsigned char data;
161 struct usb_device *dev = chip->dev;
162
163 if (fmt->protocol == UAC_VERSION_2) {
164 struct uac_clock_source_descriptor *cs_desc =
165 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
166
167 if (!cs_desc)
168 return false;
169
170 /*
171 * Assume the clock is valid if clock source supports only one
172 * single sample rate, the terminal is connected directly to it
173 * (there is no clock selector) and clock type is internal.
174 * This is to deal with some Denon DJ controllers that always
175 * reports that clock is invalid.
176 */
177 if (fmt->nr_rates == 1 &&
178 (fmt->clock & 0xff) == cs_desc->bClockID &&
179 (cs_desc->bmAttributes & 0x3) !=
180 UAC_CLOCK_SOURCE_TYPE_EXT)
181 return true;
182 }
183
184 /*
185 * MOTU MicroBook IIc
186 * Sample rate changes takes more than 2 seconds for this device. Clock
187 * validity request returns false during that period.
188 */
189 if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
190 count = 0;
191
192 while ((!ret) && (count < 50)) {
193 int err;
194
195 msleep(100);
196
197 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
198 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
199 UAC2_CS_CONTROL_CLOCK_VALID << 8,
200 snd_usb_ctrl_intf(chip) | (source_id << 8),
201 &data, sizeof(data));
202 if (err < 0) {
203 dev_warn(&dev->dev,
204 "%s(): cannot get clock validity for id %d\n",
205 __func__, source_id);
206 return false;
207 }
208
209 ret = !!data;
210 count++;
211 }
212 }
213
214 return ret;
215}
216
217static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
218 struct audioformat *fmt,
219 int source_id)
220{
221 int err;
222 unsigned char data;
223 struct usb_device *dev = chip->dev;
224 u32 bmControls;
225
226 if (fmt->protocol == UAC_VERSION_3) {
227 struct uac3_clock_source_descriptor *cs_desc =
228 snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
229
230 if (!cs_desc)
231 return false;
232 bmControls = le32_to_cpu(cs_desc->bmControls);
233 } else { /* UAC_VERSION_1/2 */
234 struct uac_clock_source_descriptor *cs_desc =
235 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
236
237 if (!cs_desc)
238 return false;
239 bmControls = cs_desc->bmControls;
240 }
241
242 /* If a clock source can't tell us whether it's valid, we assume it is */
243 if (!uac_v2v3_control_is_readable(bmControls,
244 UAC2_CS_CONTROL_CLOCK_VALID))
245 return true;
246
247 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
248 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
249 UAC2_CS_CONTROL_CLOCK_VALID << 8,
250 snd_usb_ctrl_intf(chip) | (source_id << 8),
251 &data, sizeof(data));
252
253 if (err < 0) {
254 dev_warn(&dev->dev,
255 "%s(): cannot get clock validity for id %d\n",
256 __func__, source_id);
257 return false;
258 }
259
260 if (data)
261 return true;
262 else
263 return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
264}
265
266static int __uac_clock_find_source(struct snd_usb_audio *chip,
267 struct audioformat *fmt, int entity_id,
268 unsigned long *visited, bool validate)
269{
270 struct uac_clock_source_descriptor *source;
271 struct uac_clock_selector_descriptor *selector;
272 struct uac_clock_multiplier_descriptor *multiplier;
273
274 entity_id &= 0xff;
275
276 if (test_and_set_bit(entity_id, visited)) {
277 usb_audio_warn(chip,
278 "%s(): recursive clock topology detected, id %d.\n",
279 __func__, entity_id);
280 return -EINVAL;
281 }
282
283 /* first, see if the ID we're looking for is a clock source already */
284 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
285 if (source) {
286 entity_id = source->bClockID;
287 if (validate && !uac_clock_source_is_valid(chip, fmt,
288 entity_id)) {
289 usb_audio_err(chip,
290 "clock source %d is not valid, cannot use\n",
291 entity_id);
292 return -ENXIO;
293 }
294 return entity_id;
295 }
296
297 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
298 if (selector) {
299 int ret, i, cur;
300
301 /* the entity ID we are looking for is a selector.
302 * find out what it currently selects */
303 ret = uac_clock_selector_get_val(chip, selector->bClockID);
304 if (ret < 0)
305 return ret;
306
307 /* Selector values are one-based */
308
309 if (ret > selector->bNrInPins || ret < 1) {
310 usb_audio_err(chip,
311 "%s(): selector reported illegal value, id %d, ret %d\n",
312 __func__, selector->bClockID, ret);
313
314 return -EINVAL;
315 }
316
317 cur = ret;
318 ret = __uac_clock_find_source(chip, fmt,
319 selector->baCSourceID[ret - 1],
320 visited, validate);
321 if (!validate || ret > 0 || !chip->autoclock)
322 return ret;
323
324 /* The current clock source is invalid, try others. */
325 for (i = 1; i <= selector->bNrInPins; i++) {
326 int err;
327
328 if (i == cur)
329 continue;
330
331 ret = __uac_clock_find_source(chip, fmt,
332 selector->baCSourceID[i - 1],
333 visited, true);
334 if (ret < 0)
335 continue;
336
337 err = uac_clock_selector_set_val(chip, entity_id, i);
338 if (err < 0)
339 continue;
340
341 usb_audio_info(chip,
342 "found and selected valid clock source %d\n",
343 ret);
344 return ret;
345 }
346
347 return -ENXIO;
348 }
349
350 /* FIXME: multipliers only act as pass-thru element for now */
351 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
352 if (multiplier)
353 return __uac_clock_find_source(chip, fmt,
354 multiplier->bCSourceID,
355 visited, validate);
356
357 return -EINVAL;
358}
359
360static int __uac3_clock_find_source(struct snd_usb_audio *chip,
361 struct audioformat *fmt, int entity_id,
362 unsigned long *visited, bool validate)
363{
364 struct uac3_clock_source_descriptor *source;
365 struct uac3_clock_selector_descriptor *selector;
366 struct uac3_clock_multiplier_descriptor *multiplier;
367
368 entity_id &= 0xff;
369
370 if (test_and_set_bit(entity_id, visited)) {
371 usb_audio_warn(chip,
372 "%s(): recursive clock topology detected, id %d.\n",
373 __func__, entity_id);
374 return -EINVAL;
375 }
376
377 /* first, see if the ID we're looking for is a clock source already */
378 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
379 if (source) {
380 entity_id = source->bClockID;
381 if (validate && !uac_clock_source_is_valid(chip, fmt,
382 entity_id)) {
383 usb_audio_err(chip,
384 "clock source %d is not valid, cannot use\n",
385 entity_id);
386 return -ENXIO;
387 }
388 return entity_id;
389 }
390
391 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
392 if (selector) {
393 int ret, i, cur;
394
395 /* the entity ID we are looking for is a selector.
396 * find out what it currently selects */
397 ret = uac_clock_selector_get_val(chip, selector->bClockID);
398 if (ret < 0)
399 return ret;
400
401 /* Selector values are one-based */
402
403 if (ret > selector->bNrInPins || ret < 1) {
404 usb_audio_err(chip,
405 "%s(): selector reported illegal value, id %d, ret %d\n",
406 __func__, selector->bClockID, ret);
407
408 return -EINVAL;
409 }
410
411 cur = ret;
412 ret = __uac3_clock_find_source(chip, fmt,
413 selector->baCSourceID[ret - 1],
414 visited, validate);
415 if (!validate || ret > 0 || !chip->autoclock)
416 return ret;
417
418 /* The current clock source is invalid, try others. */
419 for (i = 1; i <= selector->bNrInPins; i++) {
420 int err;
421
422 if (i == cur)
423 continue;
424
425 ret = __uac3_clock_find_source(chip, fmt,
426 selector->baCSourceID[i - 1],
427 visited, true);
428 if (ret < 0)
429 continue;
430
431 err = uac_clock_selector_set_val(chip, entity_id, i);
432 if (err < 0)
433 continue;
434
435 usb_audio_info(chip,
436 "found and selected valid clock source %d\n",
437 ret);
438 return ret;
439 }
440
441 return -ENXIO;
442 }
443
444 /* FIXME: multipliers only act as pass-thru element for now */
445 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
446 entity_id);
447 if (multiplier)
448 return __uac3_clock_find_source(chip, fmt,
449 multiplier->bCSourceID,
450 visited, validate);
451
452 return -EINVAL;
453}
454
455/*
456 * For all kinds of sample rate settings and other device queries,
457 * the clock source (end-leaf) must be used. However, clock selectors,
458 * clock multipliers and sample rate converters may be specified as
459 * clock source input to terminal. This functions walks the clock path
460 * to its end and tries to find the source.
461 *
462 * The 'visited' bitfield is used internally to detect recursive loops.
463 *
464 * Returns the clock source UnitID (>=0) on success, or an error.
465 */
466int snd_usb_clock_find_source(struct snd_usb_audio *chip,
467 struct audioformat *fmt, bool validate)
468{
469 DECLARE_BITMAP(visited, 256);
470 memset(visited, 0, sizeof(visited));
471
472 switch (fmt->protocol) {
473 case UAC_VERSION_2:
474 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
475 validate);
476 case UAC_VERSION_3:
477 return __uac3_clock_find_source(chip, fmt, fmt->clock, visited,
478 validate);
479 default:
480 return -EINVAL;
481 }
482}
483
484static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
485 struct usb_host_interface *alts,
486 struct audioformat *fmt, int rate)
487{
488 struct usb_device *dev = chip->dev;
489 unsigned int ep;
490 unsigned char data[3];
491 int err, crate;
492
493 if (get_iface_desc(alts)->bNumEndpoints < 1)
494 return -EINVAL;
495 ep = get_endpoint(alts, 0)->bEndpointAddress;
496
497 /* if endpoint doesn't have sampling rate control, bail out */
498 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
499 return 0;
500
501 data[0] = rate;
502 data[1] = rate >> 8;
503 data[2] = rate >> 16;
504 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
505 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
506 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
507 data, sizeof(data));
508 if (err < 0) {
509 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
510 iface, fmt->altsetting, rate, ep);
511 return err;
512 }
513
514 /* Don't check the sample rate for devices which we know don't
515 * support reading */
516 if (snd_usb_get_sample_rate_quirk(chip))
517 return 0;
518 /* the firmware is likely buggy, don't repeat to fail too many times */
519 if (chip->sample_rate_read_error > 2)
520 return 0;
521
522 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
523 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
524 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
525 data, sizeof(data));
526 if (err < 0) {
527 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
528 iface, fmt->altsetting, ep);
529 chip->sample_rate_read_error++;
530 return 0; /* some devices don't support reading */
531 }
532
533 crate = data[0] | (data[1] << 8) | (data[2] << 16);
534 if (crate != rate) {
535 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
536 // runtime->rate = crate;
537 }
538
539 return 0;
540}
541
542static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
543 int altsetting, int clock)
544{
545 struct usb_device *dev = chip->dev;
546 __le32 data;
547 int err;
548
549 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
550 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
551 UAC2_CS_CONTROL_SAM_FREQ << 8,
552 snd_usb_ctrl_intf(chip) | (clock << 8),
553 &data, sizeof(data));
554 if (err < 0) {
555 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
556 iface, altsetting, err);
557 return 0;
558 }
559
560 return le32_to_cpu(data);
561}
562
563static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
564 struct usb_host_interface *alts,
565 struct audioformat *fmt, int rate)
566{
567 struct usb_device *dev = chip->dev;
568 __le32 data;
569 int err, cur_rate, prev_rate;
570 int clock;
571 bool writeable;
572 u32 bmControls;
573
574 /* First, try to find a valid clock. This may trigger
575 * automatic clock selection if the current clock is not
576 * valid.
577 */
578 clock = snd_usb_clock_find_source(chip, fmt, true);
579 if (clock < 0) {
580 /* We did not find a valid clock, but that might be
581 * because the current sample rate does not match an
582 * external clock source. Try again without validation
583 * and we will do another validation after setting the
584 * rate.
585 */
586 clock = snd_usb_clock_find_source(chip, fmt, false);
587 if (clock < 0)
588 return clock;
589 }
590
591 prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
592 if (prev_rate == rate)
593 goto validation;
594
595 if (fmt->protocol == UAC_VERSION_3) {
596 struct uac3_clock_source_descriptor *cs_desc;
597
598 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
599 bmControls = le32_to_cpu(cs_desc->bmControls);
600 } else {
601 struct uac_clock_source_descriptor *cs_desc;
602
603 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
604 bmControls = cs_desc->bmControls;
605 }
606
607 writeable = uac_v2v3_control_is_writeable(bmControls,
608 UAC2_CS_CONTROL_SAM_FREQ);
609 if (writeable) {
610 data = cpu_to_le32(rate);
611 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
612 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
613 UAC2_CS_CONTROL_SAM_FREQ << 8,
614 snd_usb_ctrl_intf(chip) | (clock << 8),
615 &data, sizeof(data));
616 if (err < 0) {
617 usb_audio_err(chip,
618 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
619 iface, fmt->altsetting, rate, err);
620 return err;
621 }
622
623 cur_rate = get_sample_rate_v2v3(chip, iface,
624 fmt->altsetting, clock);
625 } else {
626 cur_rate = prev_rate;
627 }
628
629 if (cur_rate != rate) {
630 if (!writeable) {
631 usb_audio_warn(chip,
632 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
633 iface, fmt->altsetting, rate, cur_rate);
634 return -ENXIO;
635 }
636 usb_audio_dbg(chip,
637 "current rate %d is different from the runtime rate %d\n",
638 cur_rate, rate);
639 }
640
641 /* Some devices doesn't respond to sample rate changes while the
642 * interface is active. */
643 if (rate != prev_rate) {
644 usb_set_interface(dev, iface, 0);
645 snd_usb_set_interface_quirk(dev);
646 usb_set_interface(dev, iface, fmt->altsetting);
647 snd_usb_set_interface_quirk(dev);
648 }
649
650validation:
651 /* validate clock after rate change */
652 if (!uac_clock_source_is_valid(chip, fmt, clock))
653 return -ENXIO;
654 return 0;
655}
656
657int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
658 struct usb_host_interface *alts,
659 struct audioformat *fmt, int rate)
660{
661 switch (fmt->protocol) {
662 case UAC_VERSION_1:
663 default:
664 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
665
666 case UAC_VERSION_3:
667 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
668 if (rate != UAC3_BADD_SAMPLING_RATE)
669 return -ENXIO;
670 else
671 return 0;
672 }
673 fallthrough;
674 case UAC_VERSION_2:
675 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
676 }
677}
678
1/*
2 * Clock domain and sample rate management functions
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 */
19
20#include <linux/bitops.h>
21#include <linux/init.h>
22#include <linux/string.h>
23#include <linux/usb.h>
24#include <linux/usb/audio.h>
25#include <linux/usb/audio-v2.h>
26
27#include <sound/core.h>
28#include <sound/info.h>
29#include <sound/pcm.h>
30
31#include "usbaudio.h"
32#include "card.h"
33#include "helper.h"
34#include "clock.h"
35
36static struct uac_clock_source_descriptor *
37 snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
38 int clock_id)
39{
40 struct uac_clock_source_descriptor *cs = NULL;
41
42 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
43 ctrl_iface->extralen,
44 cs, UAC2_CLOCK_SOURCE))) {
45 if (cs->bClockID == clock_id)
46 return cs;
47 }
48
49 return NULL;
50}
51
52static struct uac_clock_selector_descriptor *
53 snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
54 int clock_id)
55{
56 struct uac_clock_selector_descriptor *cs = NULL;
57
58 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
59 ctrl_iface->extralen,
60 cs, UAC2_CLOCK_SELECTOR))) {
61 if (cs->bClockID == clock_id)
62 return cs;
63 }
64
65 return NULL;
66}
67
68static struct uac_clock_multiplier_descriptor *
69 snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
70 int clock_id)
71{
72 struct uac_clock_multiplier_descriptor *cs = NULL;
73
74 while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
75 ctrl_iface->extralen,
76 cs, UAC2_CLOCK_MULTIPLIER))) {
77 if (cs->bClockID == clock_id)
78 return cs;
79 }
80
81 return NULL;
82}
83
84static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
85{
86 unsigned char buf;
87 int ret;
88
89 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
90 UAC2_CS_CUR,
91 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
92 UAC2_CX_CLOCK_SELECTOR << 8,
93 snd_usb_ctrl_intf(chip) | (selector_id << 8),
94 &buf, sizeof(buf), 1000);
95
96 if (ret < 0)
97 return ret;
98
99 return buf;
100}
101
102static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
103{
104 int err;
105 unsigned char data;
106 struct usb_device *dev = chip->dev;
107 struct uac_clock_source_descriptor *cs_desc =
108 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
109
110 if (!cs_desc)
111 return 0;
112
113 /* If a clock source can't tell us whether it's valid, we assume it is */
114 if (!uac2_control_is_readable(cs_desc->bmControls, UAC2_CS_CONTROL_CLOCK_VALID))
115 return 1;
116
117 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
118 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
119 UAC2_CS_CONTROL_CLOCK_VALID << 8,
120 snd_usb_ctrl_intf(chip) | (source_id << 8),
121 &data, sizeof(data), 1000);
122
123 if (err < 0) {
124 snd_printk(KERN_WARNING "%s(): cannot get clock validity for id %d\n",
125 __func__, source_id);
126 return 0;
127 }
128
129 return !!data;
130}
131
132static int __uac_clock_find_source(struct snd_usb_audio *chip,
133 int entity_id, unsigned long *visited)
134{
135 struct uac_clock_source_descriptor *source;
136 struct uac_clock_selector_descriptor *selector;
137 struct uac_clock_multiplier_descriptor *multiplier;
138
139 entity_id &= 0xff;
140
141 if (test_and_set_bit(entity_id, visited)) {
142 snd_printk(KERN_WARNING
143 "%s(): recursive clock topology detected, id %d.\n",
144 __func__, entity_id);
145 return -EINVAL;
146 }
147
148 /* first, see if the ID we're looking for is a clock source already */
149 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
150 if (source)
151 return source->bClockID;
152
153 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
154 if (selector) {
155 int ret;
156
157 /* the entity ID we are looking for is a selector.
158 * find out what it currently selects */
159 ret = uac_clock_selector_get_val(chip, selector->bClockID);
160 if (ret < 0)
161 return ret;
162
163 /* Selector values are one-based */
164
165 if (ret > selector->bNrInPins || ret < 1) {
166 printk(KERN_ERR
167 "%s(): selector reported illegal value, id %d, ret %d\n",
168 __func__, selector->bClockID, ret);
169
170 return -EINVAL;
171 }
172
173 return __uac_clock_find_source(chip, selector->baCSourceID[ret-1],
174 visited);
175 }
176
177 /* FIXME: multipliers only act as pass-thru element for now */
178 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
179 if (multiplier)
180 return __uac_clock_find_source(chip, multiplier->bCSourceID,
181 visited);
182
183 return -EINVAL;
184}
185
186/*
187 * For all kinds of sample rate settings and other device queries,
188 * the clock source (end-leaf) must be used. However, clock selectors,
189 * clock multipliers and sample rate converters may be specified as
190 * clock source input to terminal. This functions walks the clock path
191 * to its end and tries to find the source.
192 *
193 * The 'visited' bitfield is used internally to detect recursive loops.
194 *
195 * Returns the clock source UnitID (>=0) on success, or an error.
196 */
197int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id)
198{
199 DECLARE_BITMAP(visited, 256);
200 memset(visited, 0, sizeof(visited));
201 return __uac_clock_find_source(chip, entity_id, visited);
202}
203
204static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
205 struct usb_host_interface *alts,
206 struct audioformat *fmt, int rate)
207{
208 struct usb_device *dev = chip->dev;
209 unsigned int ep;
210 unsigned char data[3];
211 int err, crate;
212
213 ep = get_endpoint(alts, 0)->bEndpointAddress;
214
215 /* if endpoint doesn't have sampling rate control, bail out */
216 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
217 return 0;
218
219 data[0] = rate;
220 data[1] = rate >> 8;
221 data[2] = rate >> 16;
222 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
223 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
224 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
225 data, sizeof(data), 1000)) < 0) {
226 snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d to ep %#x\n",
227 dev->devnum, iface, fmt->altsetting, rate, ep);
228 return err;
229 }
230
231 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
232 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
233 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
234 data, sizeof(data), 1000)) < 0) {
235 snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq at ep %#x\n",
236 dev->devnum, iface, fmt->altsetting, ep);
237 return 0; /* some devices don't support reading */
238 }
239
240 crate = data[0] | (data[1] << 8) | (data[2] << 16);
241 if (crate != rate) {
242 snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
243 // runtime->rate = crate;
244 }
245
246 return 0;
247}
248
249static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
250 struct usb_host_interface *alts,
251 struct audioformat *fmt, int rate)
252{
253 struct usb_device *dev = chip->dev;
254 unsigned char data[4];
255 int err, crate;
256 int clock = snd_usb_clock_find_source(chip, fmt->clock);
257
258 if (clock < 0)
259 return clock;
260
261 if (!uac_clock_source_is_valid(chip, clock)) {
262 /* TODO: should we try to find valid clock setups by ourself? */
263 snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n",
264 dev->devnum, iface, fmt->altsetting, clock);
265 return -ENXIO;
266 }
267
268 data[0] = rate;
269 data[1] = rate >> 8;
270 data[2] = rate >> 16;
271 data[3] = rate >> 24;
272 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
273 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
274 UAC2_CS_CONTROL_SAM_FREQ << 8,
275 snd_usb_ctrl_intf(chip) | (clock << 8),
276 data, sizeof(data), 1000)) < 0) {
277 snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d (v2)\n",
278 dev->devnum, iface, fmt->altsetting, rate);
279 return err;
280 }
281
282 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
283 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
284 UAC2_CS_CONTROL_SAM_FREQ << 8,
285 snd_usb_ctrl_intf(chip) | (clock << 8),
286 data, sizeof(data), 1000)) < 0) {
287 snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq (v2)\n",
288 dev->devnum, iface, fmt->altsetting);
289 return err;
290 }
291
292 crate = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
293 if (crate != rate)
294 snd_printd(KERN_WARNING "current rate %d is different from the runtime rate %d\n", crate, rate);
295
296 return 0;
297}
298
299int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
300 struct usb_host_interface *alts,
301 struct audioformat *fmt, int rate)
302{
303 struct usb_interface_descriptor *altsd = get_iface_desc(alts);
304
305 switch (altsd->bInterfaceProtocol) {
306 case UAC_VERSION_1:
307 default:
308 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
309
310 case UAC_VERSION_2:
311 return set_sample_rate_v2(chip, iface, alts, fmt, rate);
312 }
313}
314