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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
24union uac23_clock_source_desc {
25 struct uac_clock_source_descriptor v2;
26 struct uac3_clock_source_descriptor v3;
27};
28
29union uac23_clock_selector_desc {
30 struct uac_clock_selector_descriptor v2;
31 struct uac3_clock_selector_descriptor v3;
32};
33
34union uac23_clock_multiplier_desc {
35 struct uac_clock_multiplier_descriptor v2;
36 struct uac_clock_multiplier_descriptor v3;
37};
38
39/* check whether the descriptor bLength has the minimal length */
40#define DESC_LENGTH_CHECK(p, proto) \
41 ((proto) == UAC_VERSION_3 ? \
42 ((p)->v3.bLength >= sizeof((p)->v3)) : \
43 ((p)->v2.bLength >= sizeof((p)->v2)))
44
45#define GET_VAL(p, proto, field) \
46 ((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
47
48static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
49 bool (*validator)(void *, int, int),
50 u8 type, int proto)
51{
52 void *cs = NULL;
53
54 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
55 cs, type))) {
56 if (validator(cs, id, proto))
57 return cs;
58 }
59
60 return NULL;
61}
62
63static bool validate_clock_source(void *p, int id, int proto)
64{
65 union uac23_clock_source_desc *cs = p;
66
67 if (!DESC_LENGTH_CHECK(cs, proto))
68 return false;
69 return GET_VAL(cs, proto, bClockID) == id;
70}
71
72static bool validate_clock_selector(void *p, int id, int proto)
73{
74 union uac23_clock_selector_desc *cs = p;
75
76 if (!DESC_LENGTH_CHECK(cs, proto))
77 return false;
78 if (GET_VAL(cs, proto, bClockID) != id)
79 return false;
80 /* additional length check for baCSourceID array (in bNrInPins size)
81 * and two more fields (which sizes depend on the protocol)
82 */
83 if (proto == UAC_VERSION_3)
84 return cs->v3.bLength >= sizeof(cs->v3) + cs->v3.bNrInPins +
85 4 /* bmControls */ + 2 /* wCSelectorDescrStr */;
86 else
87 return cs->v2.bLength >= sizeof(cs->v2) + cs->v2.bNrInPins +
88 1 /* bmControls */ + 1 /* iClockSelector */;
89}
90
91static bool validate_clock_multiplier(void *p, int id, int proto)
92{
93 union uac23_clock_multiplier_desc *cs = p;
94
95 if (!DESC_LENGTH_CHECK(cs, proto))
96 return false;
97 return GET_VAL(cs, proto, bClockID) == id;
98}
99
100#define DEFINE_FIND_HELPER(name, obj, validator, type2, type3) \
101static obj *name(struct snd_usb_audio *chip, int id, \
102 const struct audioformat *fmt) \
103{ \
104 struct usb_host_interface *ctrl_intf = \
105 snd_usb_find_ctrl_interface(chip, fmt->iface); \
106 return find_uac_clock_desc(ctrl_intf, id, validator, \
107 fmt->protocol == UAC_VERSION_3 ? (type3) : (type2), \
108 fmt->protocol); \
109}
110
111DEFINE_FIND_HELPER(snd_usb_find_clock_source,
112 union uac23_clock_source_desc, validate_clock_source,
113 UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
114DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
115 union uac23_clock_selector_desc, validate_clock_selector,
116 UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
117DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
118 union uac23_clock_multiplier_desc, validate_clock_multiplier,
119 UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
120
121static int uac_clock_selector_get_val(struct snd_usb_audio *chip,
122 int selector_id, int iface_no)
123{
124 struct usb_host_interface *ctrl_intf;
125 unsigned char buf;
126 int ret;
127
128 ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
129 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
130 UAC2_CS_CUR,
131 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
132 UAC2_CX_CLOCK_SELECTOR << 8,
133 snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
134 &buf, sizeof(buf));
135
136 if (ret < 0)
137 return ret;
138
139 return buf;
140}
141
142static int uac_clock_selector_set_val(struct snd_usb_audio *chip,
143 int selector_id, unsigned char pin, int iface_no)
144{
145 struct usb_host_interface *ctrl_intf;
146 int ret;
147
148 ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
149 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
150 UAC2_CS_CUR,
151 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
152 UAC2_CX_CLOCK_SELECTOR << 8,
153 snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
154 &pin, sizeof(pin));
155 if (ret < 0)
156 return ret;
157
158 if (ret != sizeof(pin)) {
159 usb_audio_err(chip,
160 "setting selector (id %d) unexpected length %d\n",
161 selector_id, ret);
162 return -EINVAL;
163 }
164
165 ret = uac_clock_selector_get_val(chip, selector_id, iface_no);
166 if (ret < 0)
167 return ret;
168
169 if (ret != pin) {
170 usb_audio_err(chip,
171 "setting selector (id %d) to %x failed (current: %d)\n",
172 selector_id, pin, ret);
173 return -EINVAL;
174 }
175
176 return ret;
177}
178
179static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
180 const struct audioformat *fmt,
181 int source_id)
182{
183 bool ret = false;
184 int count;
185 unsigned char data;
186 struct usb_device *dev = chip->dev;
187 union uac23_clock_source_desc *cs_desc;
188 struct usb_host_interface *ctrl_intf;
189
190 ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
191 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
192 if (!cs_desc)
193 return false;
194
195 if (fmt->protocol == UAC_VERSION_2) {
196 /*
197 * Assume the clock is valid if clock source supports only one
198 * single sample rate, the terminal is connected directly to it
199 * (there is no clock selector) and clock type is internal.
200 * This is to deal with some Denon DJ controllers that always
201 * reports that clock is invalid.
202 */
203 if (fmt->nr_rates == 1 &&
204 (fmt->clock & 0xff) == cs_desc->v2.bClockID &&
205 (cs_desc->v2.bmAttributes & 0x3) !=
206 UAC_CLOCK_SOURCE_TYPE_EXT)
207 return true;
208 }
209
210 /*
211 * Quirk for older MOTU AVB / hybrid interfaces
212 *
213 * These devices take more than 2 seconds to switch sample rate or
214 * clock source. During this period the clock validity request
215 * returns false, causing ALSA to fail prematurely.
216 *
217 * Affected models (all use vendor 0x07fd):
218 * - MicroBook IIc → 0x0004
219 * - 1248, 624, 8A, UltraLite AVB, 8M, 16A, ... → 0x0005
220 */
221 if (chip->usb_id == USB_ID(0x07fd, 0x0004) || /* MicroBook IIc */
222 chip->usb_id == USB_ID(0x07fd, 0x0005)) { /* 1248 / 624 / 8A / UltraLite AVB / ... */
223 count = 0;
224
225 while ((!ret) && (count < 50)) {
226 int err;
227
228 msleep(100);
229
230 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
231 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
232 UAC2_CS_CONTROL_CLOCK_VALID << 8,
233 snd_usb_ctrl_intf(ctrl_intf) | (source_id << 8),
234 &data, sizeof(data));
235 if (err < 0) {
236 dev_warn(&dev->dev,
237 "%s(): cannot get clock validity for id %d\n",
238 __func__, source_id);
239 return false;
240 }
241
242 ret = !!data;
243 count++;
244 }
245 }
246
247 return ret;
248}
249
250static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
251 const struct audioformat *fmt,
252 int source_id)
253{
254 int err;
255 unsigned char data;
256 struct usb_device *dev = chip->dev;
257 u32 bmControls;
258 union uac23_clock_source_desc *cs_desc;
259 struct usb_host_interface *ctrl_intf;
260
261 ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
262 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
263 if (!cs_desc)
264 return false;
265
266 if (fmt->protocol == UAC_VERSION_3)
267 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
268 else
269 bmControls = cs_desc->v2.bmControls;
270
271 /* If a clock source can't tell us whether it's valid, we assume it is */
272 if (!uac_v2v3_control_is_readable(bmControls,
273 UAC2_CS_CONTROL_CLOCK_VALID))
274 return true;
275
276 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
277 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
278 UAC2_CS_CONTROL_CLOCK_VALID << 8,
279 snd_usb_ctrl_intf(ctrl_intf) | (source_id << 8),
280 &data, sizeof(data));
281
282 if (err < 0) {
283 dev_warn(&dev->dev,
284 "%s(): cannot get clock validity for id %d\n",
285 __func__, source_id);
286 return false;
287 }
288
289 if (data)
290 return true;
291 else
292 return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
293}
294
295static int __uac_clock_find_source(struct snd_usb_audio *chip,
296 const struct audioformat *fmt, int entity_id,
297 unsigned long *visited, bool validate)
298{
299 union uac23_clock_source_desc *source;
300 union uac23_clock_selector_desc *selector;
301 union uac23_clock_multiplier_desc *multiplier;
302 int ret, i, cur, err, pins, clock_id;
303 const u8 *sources;
304 int proto = fmt->protocol;
305 bool readable, writeable;
306 u32 bmControls;
307
308 entity_id &= 0xff;
309
310 if (test_and_set_bit(entity_id, visited)) {
311 usb_audio_warn(chip,
312 "%s(): recursive clock topology detected, id %d.\n",
313 __func__, entity_id);
314 return -EINVAL;
315 }
316
317 /* first, see if the ID we're looking at is a clock source already */
318 source = snd_usb_find_clock_source(chip, entity_id, fmt);
319 if (source) {
320 entity_id = GET_VAL(source, proto, bClockID);
321 if (validate && !uac_clock_source_is_valid(chip, fmt,
322 entity_id)) {
323 usb_audio_err(chip,
324 "clock source %d is not valid, cannot use\n",
325 entity_id);
326 return -ENXIO;
327 }
328 return entity_id;
329 }
330
331 selector = snd_usb_find_clock_selector(chip, entity_id, fmt);
332 if (selector) {
333 pins = GET_VAL(selector, proto, bNrInPins);
334 clock_id = GET_VAL(selector, proto, bClockID);
335 sources = GET_VAL(selector, proto, baCSourceID);
336 cur = 0;
337
338 if (proto == UAC_VERSION_3)
339 bmControls = le32_to_cpu(*(__le32 *)(&selector->v3.baCSourceID[0] + pins));
340 else
341 bmControls = *(__u8 *)(&selector->v2.baCSourceID[0] + pins);
342
343 readable = uac_v2v3_control_is_readable(bmControls,
344 UAC2_CX_CLOCK_SELECTOR);
345 writeable = uac_v2v3_control_is_writeable(bmControls,
346 UAC2_CX_CLOCK_SELECTOR);
347
348 if (pins == 1) {
349 ret = 1;
350 goto find_source;
351 }
352
353 /* for now just warn about buggy device */
354 if (!readable)
355 usb_audio_warn(chip,
356 "%s(): clock selector control is not readable, id %d\n",
357 __func__, clock_id);
358
359 /* the entity ID we are looking at is a selector.
360 * find out what it currently selects */
361 ret = uac_clock_selector_get_val(chip, clock_id, fmt->iface);
362 if (ret < 0) {
363 if (!chip->autoclock)
364 return ret;
365 goto find_others;
366 }
367
368 /* Selector values are one-based */
369
370 if (ret > pins || ret < 1) {
371 usb_audio_err(chip,
372 "%s(): selector reported illegal value, id %d, ret %d\n",
373 __func__, clock_id, ret);
374
375 if (!chip->autoclock)
376 return -EINVAL;
377 goto find_others;
378 }
379
380 find_source:
381 cur = ret;
382 ret = __uac_clock_find_source(chip, fmt,
383 sources[ret - 1],
384 visited, validate);
385 if (ret > 0) {
386 /* Skip setting clock selector again for some devices */
387 if (chip->quirk_flags & QUIRK_FLAG_SKIP_CLOCK_SELECTOR ||
388 !writeable)
389 return ret;
390 err = uac_clock_selector_set_val(chip, entity_id, cur, fmt->iface);
391 if (err < 0) {
392 if (pins == 1) {
393 usb_audio_dbg(chip,
394 "%s(): selector returned an error, "
395 "assuming a firmware bug, id %d, ret %d\n",
396 __func__, clock_id, err);
397 return ret;
398 }
399 return err;
400 }
401 }
402
403 if (!validate || ret > 0 || !chip->autoclock)
404 return ret;
405
406 find_others:
407 if (!writeable)
408 return -ENXIO;
409
410 /* The current clock source is invalid, try others. */
411 for (i = 1; i <= pins; i++) {
412 if (i == cur)
413 continue;
414
415 ret = __uac_clock_find_source(chip, fmt,
416 sources[i - 1],
417 visited, true);
418 if (ret < 0)
419 continue;
420
421 err = uac_clock_selector_set_val(chip, entity_id, i, fmt->iface);
422 if (err < 0)
423 continue;
424
425 usb_audio_info(chip,
426 "found and selected valid clock source %d\n",
427 ret);
428 return ret;
429 }
430
431 return -ENXIO;
432 }
433
434 /* FIXME: multipliers only act as pass-thru element for now */
435 multiplier = snd_usb_find_clock_multiplier(chip, entity_id, fmt);
436 if (multiplier)
437 return __uac_clock_find_source(chip, fmt,
438 GET_VAL(multiplier, proto, bCSourceID),
439 visited, validate);
440
441 return -EINVAL;
442}
443
444/*
445 * For all kinds of sample rate settings and other device queries,
446 * the clock source (end-leaf) must be used. However, clock selectors,
447 * clock multipliers and sample rate converters may be specified as
448 * clock source input to terminal. This functions walks the clock path
449 * to its end and tries to find the source.
450 *
451 * The 'visited' bitfield is used internally to detect recursive loops.
452 *
453 * Returns the clock source UnitID (>=0) on success, or an error.
454 */
455int snd_usb_clock_find_source(struct snd_usb_audio *chip,
456 const struct audioformat *fmt, bool validate)
457{
458 DECLARE_BITMAP(visited, 256);
459 memset(visited, 0, sizeof(visited));
460
461 switch (fmt->protocol) {
462 case UAC_VERSION_2:
463 case UAC_VERSION_3:
464 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
465 validate);
466 default:
467 return -EINVAL;
468 }
469}
470
471static int set_sample_rate_v1(struct snd_usb_audio *chip,
472 const struct audioformat *fmt, int rate)
473{
474 struct usb_device *dev = chip->dev;
475 unsigned char data[3];
476 int err, crate;
477
478 /* if endpoint doesn't have sampling rate control, bail out */
479 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
480 return 0;
481
482 data[0] = rate;
483 data[1] = rate >> 8;
484 data[2] = rate >> 16;
485 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
486 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
487 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
488 fmt->endpoint, data, sizeof(data));
489 if (err < 0) {
490 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
491 fmt->iface, fmt->altsetting, rate, fmt->endpoint);
492 return err;
493 }
494
495 /* Don't check the sample rate for devices which we know don't
496 * support reading */
497 if (chip->quirk_flags & QUIRK_FLAG_GET_SAMPLE_RATE)
498 return 0;
499 /* the firmware is likely buggy, don't repeat to fail too many times */
500 if (chip->sample_rate_read_error > 2)
501 return 0;
502
503 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
504 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
505 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
506 fmt->endpoint, data, sizeof(data));
507 if (err < 0) {
508 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
509 fmt->iface, fmt->altsetting, fmt->endpoint);
510 chip->sample_rate_read_error++;
511 return 0; /* some devices don't support reading */
512 }
513
514 crate = data[0] | (data[1] << 8) | (data[2] << 16);
515 if (!crate) {
516 dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
517 chip->sample_rate_read_error = 3; /* three strikes, see above */
518 return 0;
519 }
520
521 if (crate != rate) {
522 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
523 // runtime->rate = crate;
524 }
525
526 return 0;
527}
528
529static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
530 int altsetting, int clock)
531{
532 struct usb_device *dev = chip->dev;
533 __le32 data;
534 int err;
535 struct usb_host_interface *ctrl_intf;
536
537 ctrl_intf = snd_usb_find_ctrl_interface(chip, iface);
538 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
539 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
540 UAC2_CS_CONTROL_SAM_FREQ << 8,
541 snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
542 &data, sizeof(data));
543 if (err < 0) {
544 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
545 iface, altsetting, err);
546 return 0;
547 }
548
549 return le32_to_cpu(data);
550}
551
552/*
553 * Try to set the given sample rate:
554 *
555 * Return 0 if the clock source is read-only, the actual rate on success,
556 * or a negative error code.
557 *
558 * This function gets called from format.c to validate each sample rate, too.
559 * Hence no message is shown upon error
560 */
561int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
562 const struct audioformat *fmt,
563 int clock, int rate)
564{
565 bool writeable;
566 u32 bmControls;
567 __le32 data;
568 int err;
569 union uac23_clock_source_desc *cs_desc;
570 struct usb_host_interface *ctrl_intf;
571
572 ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
573 cs_desc = snd_usb_find_clock_source(chip, clock, fmt);
574
575 if (!cs_desc)
576 return 0;
577
578 if (fmt->protocol == UAC_VERSION_3)
579 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
580 else
581 bmControls = cs_desc->v2.bmControls;
582
583 writeable = uac_v2v3_control_is_writeable(bmControls,
584 UAC2_CS_CONTROL_SAM_FREQ);
585 if (!writeable)
586 return 0;
587
588 data = cpu_to_le32(rate);
589 err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
590 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
591 UAC2_CS_CONTROL_SAM_FREQ << 8,
592 snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
593 &data, sizeof(data));
594 if (err < 0)
595 return err;
596
597 return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
598}
599
600static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
601 const struct audioformat *fmt, int rate)
602{
603 int cur_rate, prev_rate = 0;
604 int clock;
605
606 /* First, try to find a valid clock. This may trigger
607 * automatic clock selection if the current clock is not
608 * valid.
609 */
610 clock = snd_usb_clock_find_source(chip, fmt, true);
611 if (clock < 0) {
612 /* We did not find a valid clock, but that might be
613 * because the current sample rate does not match an
614 * external clock source. Try again without validation
615 * and we will do another validation after setting the
616 * rate.
617 */
618 clock = snd_usb_clock_find_source(chip, fmt, false);
619
620 /* Hardcoded sample rates */
621 if (chip->quirk_flags & QUIRK_FLAG_IGNORE_CLOCK_SOURCE)
622 return 0;
623
624 if (clock < 0)
625 return clock;
626 }
627
628 if (!(chip->quirk_flags & QUIRK_FLAG_ALWAYS_SET_RATE)) {
629 prev_rate = get_sample_rate_v2v3(chip, fmt->iface,
630 fmt->altsetting, clock);
631 if (prev_rate == rate)
632 goto validation;
633 }
634
635 cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
636 if (cur_rate < 0) {
637 usb_audio_err(chip,
638 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
639 fmt->iface, fmt->altsetting, rate, cur_rate);
640 return cur_rate;
641 }
642
643 if (!cur_rate)
644 cur_rate = prev_rate;
645
646 if (cur_rate != rate) {
647 usb_audio_dbg(chip,
648 "%d:%d: freq mismatch: req %d, clock runs @%d\n",
649 fmt->iface, fmt->altsetting, rate, cur_rate);
650 /* continue processing */
651 }
652
653 /* FIXME - TEAC devices require the immediate interface setup */
654 if (USB_ID_VENDOR(chip->usb_id) == 0x0644) {
655 bool cur_base_48k = (rate % 48000 == 0);
656 bool prev_base_48k = (prev_rate % 48000 == 0);
657 if (cur_base_48k != prev_base_48k) {
658 usb_set_interface(chip->dev, fmt->iface, fmt->altsetting);
659 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
660 msleep(50);
661 }
662 }
663
664validation:
665 /* validate clock after rate change */
666 if (!uac_clock_source_is_valid(chip, fmt, clock))
667 return -ENXIO;
668 return 0;
669}
670
671int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
672 const struct audioformat *fmt, int rate)
673{
674 usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
675 fmt->iface, fmt->altsetting, rate, fmt->clock);
676
677 switch (fmt->protocol) {
678 case UAC_VERSION_1:
679 default:
680 return set_sample_rate_v1(chip, fmt, rate);
681
682 case UAC_VERSION_3:
683 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
684 if (rate != UAC3_BADD_SAMPLING_RATE)
685 return -ENXIO;
686 else
687 return 0;
688 }
689 fallthrough;
690 case UAC_VERSION_2:
691 return set_sample_rate_v2v3(chip, fmt, rate);
692 }
693}
694