xref: /openbmc/linux/sound/usb/clock.c (revision 6abeae2a)
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 
24 static 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 
38 static 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 
44 static 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 
50 static 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 
56 static 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 
62 static 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 
68 static 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)		\
75 static obj *name(struct usb_host_interface *iface, int id)	\
76 {								\
77 	return find_uac_clock_desc(iface, id, validator, type);	\
78 }
79 
80 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
81 		   struct uac_clock_source_descriptor,
82 		   validate_clock_source_v2, UAC2_CLOCK_SOURCE);
83 DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
84 		   struct uac3_clock_source_descriptor,
85 		   validate_clock_source_v3, UAC3_CLOCK_SOURCE);
86 
87 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
88 		   struct uac_clock_selector_descriptor,
89 		   validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
90 DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
91 		   struct uac3_clock_selector_descriptor,
92 		   validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
93 
94 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
95 		   struct uac_clock_multiplier_descriptor,
96 		   validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
97 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
98 		   struct uac3_clock_multiplier_descriptor,
99 		   validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
100 
101 static 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 
119 static 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 
154 static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
155 					    const 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 
217 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
218 				      const 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 
266 static int __uac_clock_find_source(struct snd_usb_audio *chip,
267 				   const 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 
360 static int __uac3_clock_find_source(struct snd_usb_audio *chip,
361 				    const 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  */
466 int snd_usb_clock_find_source(struct snd_usb_audio *chip,
467 			      const 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 
484 static int set_sample_rate_v1(struct snd_usb_audio *chip,
485 			      const struct audioformat *fmt, int rate)
486 {
487 	struct usb_device *dev = chip->dev;
488 	struct usb_host_interface *alts;
489 	unsigned int ep;
490 	unsigned char data[3];
491 	int err, crate;
492 
493 	alts = snd_usb_get_host_interface(chip, fmt->iface, fmt->altsetting);
494 	if (!alts)
495 		return -EINVAL;
496 	if (get_iface_desc(alts)->bNumEndpoints < 1)
497 		return -EINVAL;
498 	ep = get_endpoint(alts, 0)->bEndpointAddress;
499 
500 	/* if endpoint doesn't have sampling rate control, bail out */
501 	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
502 		return 0;
503 
504 	data[0] = rate;
505 	data[1] = rate >> 8;
506 	data[2] = rate >> 16;
507 	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
508 			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
509 			      UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
510 			      data, sizeof(data));
511 	if (err < 0) {
512 		dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
513 			fmt->iface, fmt->altsetting, rate, ep);
514 		return err;
515 	}
516 
517 	/* Don't check the sample rate for devices which we know don't
518 	 * support reading */
519 	if (snd_usb_get_sample_rate_quirk(chip))
520 		return 0;
521 	/* the firmware is likely buggy, don't repeat to fail too many times */
522 	if (chip->sample_rate_read_error > 2)
523 		return 0;
524 
525 	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
526 			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
527 			      UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
528 			      data, sizeof(data));
529 	if (err < 0) {
530 		dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
531 			fmt->iface, fmt->altsetting, ep);
532 		chip->sample_rate_read_error++;
533 		return 0; /* some devices don't support reading */
534 	}
535 
536 	crate = data[0] | (data[1] << 8) | (data[2] << 16);
537 	if (!crate) {
538 		dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
539 		chip->sample_rate_read_error = 3; /* three strikes, see above */
540 		return 0;
541 	}
542 
543 	if (crate != rate) {
544 		dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
545 		// runtime->rate = crate;
546 	}
547 
548 	return 0;
549 }
550 
551 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
552 			      int altsetting, int clock)
553 {
554 	struct usb_device *dev = chip->dev;
555 	__le32 data;
556 	int err;
557 
558 	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
559 			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
560 			      UAC2_CS_CONTROL_SAM_FREQ << 8,
561 			      snd_usb_ctrl_intf(chip) | (clock << 8),
562 			      &data, sizeof(data));
563 	if (err < 0) {
564 		dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
565 			 iface, altsetting, err);
566 		return 0;
567 	}
568 
569 	return le32_to_cpu(data);
570 }
571 
572 /*
573  * Try to set the given sample rate:
574  *
575  * Return 0 if the clock source is read-only, the actual rate on success,
576  * or a negative error code.
577  *
578  * This function gets called from format.c to validate each sample rate, too.
579  * Hence no message is shown upon error
580  */
581 int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
582 				 const struct audioformat *fmt,
583 				 int clock, int rate)
584 {
585 	bool writeable;
586 	u32 bmControls;
587 	__le32 data;
588 	int err;
589 
590 	if (fmt->protocol == UAC_VERSION_3) {
591 		struct uac3_clock_source_descriptor *cs_desc;
592 
593 		cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
594 		bmControls = le32_to_cpu(cs_desc->bmControls);
595 	} else {
596 		struct uac_clock_source_descriptor *cs_desc;
597 
598 		cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
599 		bmControls = cs_desc->bmControls;
600 	}
601 
602 	writeable = uac_v2v3_control_is_writeable(bmControls,
603 						  UAC2_CS_CONTROL_SAM_FREQ);
604 	if (!writeable)
605 		return 0;
606 
607 	data = cpu_to_le32(rate);
608 	err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
609 			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
610 			      UAC2_CS_CONTROL_SAM_FREQ << 8,
611 			      snd_usb_ctrl_intf(chip) | (clock << 8),
612 			      &data, sizeof(data));
613 	if (err < 0)
614 		return err;
615 
616 	return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
617 }
618 
619 static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
620 				const struct audioformat *fmt, int rate)
621 {
622 	int cur_rate, prev_rate;
623 	int clock;
624 
625 	/* First, try to find a valid clock. This may trigger
626 	 * automatic clock selection if the current clock is not
627 	 * valid.
628 	 */
629 	clock = snd_usb_clock_find_source(chip, fmt, true);
630 	if (clock < 0) {
631 		/* We did not find a valid clock, but that might be
632 		 * because the current sample rate does not match an
633 		 * external clock source. Try again without validation
634 		 * and we will do another validation after setting the
635 		 * rate.
636 		 */
637 		clock = snd_usb_clock_find_source(chip, fmt, false);
638 		if (clock < 0)
639 			return clock;
640 	}
641 
642 	prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
643 	if (prev_rate == rate)
644 		goto validation;
645 
646 	cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
647 	if (cur_rate < 0) {
648 		usb_audio_err(chip,
649 			      "%d:%d: cannot set freq %d (v2/v3): err %d\n",
650 			      fmt->iface, fmt->altsetting, rate, cur_rate);
651 		return cur_rate;
652 	}
653 
654 	if (!cur_rate)
655 		cur_rate = prev_rate;
656 
657 	if (cur_rate != rate) {
658 		usb_audio_warn(chip,
659 			       "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
660 			       fmt->iface, fmt->altsetting, rate, cur_rate);
661 		return -ENXIO;
662 	}
663 
664 validation:
665 	/* validate clock after rate change */
666 	if (!uac_clock_source_is_valid(chip, fmt, clock))
667 		return -ENXIO;
668 	return 0;
669 }
670 
671 int 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 
695