Linux Audio

Check our new training course

Linux debugging, profiling, tracing and performance analysis training

Apr 14-17, 2025
Register
Loading...
v4.17
 
  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#include <linux/usb/audio-v3.h>
 27
 28#include <sound/core.h>
 29#include <sound/info.h>
 30#include <sound/pcm.h>
 31
 32#include "usbaudio.h"
 33#include "card.h"
 34#include "helper.h"
 35#include "clock.h"
 36#include "quirks.h"
 37
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 38static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
 39				 bool (*validator)(void *, int), u8 type)
 
 40{
 41	void *cs = NULL;
 42
 43	while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
 44					     cs, type))) {
 45		if (validator(cs, id))
 46			return cs;
 47	}
 48
 49	return NULL;
 50}
 51
 52static bool validate_clock_source_v2(void *p, int id)
 53{
 54	struct uac_clock_source_descriptor *cs = p;
 55	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
 56}
 57
 58static bool validate_clock_source_v3(void *p, int id)
 59{
 60	struct uac3_clock_source_descriptor *cs = p;
 61	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
 62}
 63
 64static bool validate_clock_selector_v2(void *p, int id)
 65{
 66	struct uac_clock_selector_descriptor *cs = p;
 67	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
 68		cs->bLength == 7 + cs->bNrInPins;
 69}
 70
 71static bool validate_clock_selector_v3(void *p, int id)
 72{
 73	struct uac3_clock_selector_descriptor *cs = p;
 74	return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
 75		cs->bLength == 11 + cs->bNrInPins;
 
 
 
 
 
 
 
 
 76}
 77
 78static bool validate_clock_multiplier_v2(void *p, int id)
 79{
 80	struct uac_clock_multiplier_descriptor *cs = p;
 81	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
 82}
 83
 84static bool validate_clock_multiplier_v3(void *p, int id)
 85{
 86	struct uac3_clock_multiplier_descriptor *cs = p;
 87	return cs->bLength == sizeof(*cs) && cs->bClockID == id;
 88}
 89
 90#define DEFINE_FIND_HELPER(name, obj, validator, type)		\
 91static obj *name(struct usb_host_interface *iface, int id)	\
 92{								\
 93	return find_uac_clock_desc(iface, id, validator, type);	\
 
 
 
 
 
 94}
 95
 96DEFINE_FIND_HELPER(snd_usb_find_clock_source,
 97		   struct uac_clock_source_descriptor,
 98		   validate_clock_source_v2, UAC2_CLOCK_SOURCE);
 99DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
100		   struct uac3_clock_source_descriptor,
101		   validate_clock_source_v3, UAC3_CLOCK_SOURCE);
102
103DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
104		   struct uac_clock_selector_descriptor,
105		   validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
106DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
107		   struct uac3_clock_selector_descriptor,
108		   validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
109
110DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
111		   struct uac_clock_multiplier_descriptor,
112		   validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
113DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
114		   struct uac3_clock_multiplier_descriptor,
115		   validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
116
117static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
 
118{
 
119	unsigned char buf;
120	int ret;
121
 
122	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
123			      UAC2_CS_CUR,
124			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
125			      UAC2_CX_CLOCK_SELECTOR << 8,
126			      snd_usb_ctrl_intf(chip) | (selector_id << 8),
127			      &buf, sizeof(buf));
128
129	if (ret < 0)
130		return ret;
131
132	return buf;
133}
134
135static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
136					unsigned char pin)
137{
 
138	int ret;
139
 
140	ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
141			      UAC2_CS_CUR,
142			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
143			      UAC2_CX_CLOCK_SELECTOR << 8,
144			      snd_usb_ctrl_intf(chip) | (selector_id << 8),
145			      &pin, sizeof(pin));
146	if (ret < 0)
147		return ret;
148
149	if (ret != sizeof(pin)) {
150		usb_audio_err(chip,
151			"setting selector (id %d) unexpected length %d\n",
152			selector_id, ret);
153		return -EINVAL;
154	}
155
156	ret = uac_clock_selector_get_val(chip, selector_id);
157	if (ret < 0)
158		return ret;
159
160	if (ret != pin) {
161		usb_audio_err(chip,
162			"setting selector (id %d) to %x failed (current: %d)\n",
163			selector_id, pin, ret);
164		return -EINVAL;
165	}
166
167	return ret;
168}
169
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
170static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
171				      int protocol,
172				      int source_id)
173{
174	int err;
175	unsigned char data;
176	struct usb_device *dev = chip->dev;
177	u32 bmControls;
 
 
178
179	if (protocol == UAC_VERSION_3) {
180		struct uac3_clock_source_descriptor *cs_desc =
181			snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
182
183		if (!cs_desc)
184			return 0;
185		bmControls = le32_to_cpu(cs_desc->bmControls);
186	} else { /* UAC_VERSION_1/2 */
187		struct uac_clock_source_descriptor *cs_desc =
188			snd_usb_find_clock_source(chip->ctrl_intf, source_id);
189
190		if (!cs_desc)
191			return 0;
192		bmControls = cs_desc->bmControls;
193	}
194
195	/* If a clock source can't tell us whether it's valid, we assume it is */
196	if (!uac_v2v3_control_is_readable(bmControls,
197				      UAC2_CS_CONTROL_CLOCK_VALID))
198		return 1;
199
200	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
201			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
202			      UAC2_CS_CONTROL_CLOCK_VALID << 8,
203			      snd_usb_ctrl_intf(chip) | (source_id << 8),
204			      &data, sizeof(data));
205
206	if (err < 0) {
207		dev_warn(&dev->dev,
208			 "%s(): cannot get clock validity for id %d\n",
209			   __func__, source_id);
210		return 0;
211	}
212
213	return !!data;
 
 
 
214}
215
216static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
 
217				   unsigned long *visited, bool validate)
218{
219	struct uac_clock_source_descriptor *source;
220	struct uac_clock_selector_descriptor *selector;
221	struct uac_clock_multiplier_descriptor *multiplier;
 
 
 
 
 
222
223	entity_id &= 0xff;
224
225	if (test_and_set_bit(entity_id, visited)) {
226		usb_audio_warn(chip,
227			 "%s(): recursive clock topology detected, id %d.\n",
228			 __func__, entity_id);
229		return -EINVAL;
230	}
231
232	/* first, see if the ID we're looking for is a clock source already */
233	source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
234	if (source) {
235		entity_id = source->bClockID;
236		if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
237								entity_id)) {
238			usb_audio_err(chip,
239				"clock source %d is not valid, cannot use\n",
240				entity_id);
241			return -ENXIO;
242		}
243		return entity_id;
244	}
245
246	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
247	if (selector) {
248		int ret, i, cur;
249
250		/* the entity ID we are looking for is a selector.
251		 * find out what it currently selects */
252		ret = uac_clock_selector_get_val(chip, selector->bClockID);
253		if (ret < 0)
254			return ret;
255
256		/* Selector values are one-based */
257
258		if (ret > selector->bNrInPins || ret < 1) {
259			usb_audio_err(chip,
260				"%s(): selector reported illegal value, id %d, ret %d\n",
261				__func__, selector->bClockID, ret);
262
263			return -EINVAL;
 
 
264		}
265
266		cur = ret;
267		ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
268					       visited, validate);
269		if (!validate || ret > 0 || !chip->autoclock)
270			return ret;
271
272		/* The current clock source is invalid, try others. */
273		for (i = 1; i <= selector->bNrInPins; i++) {
274			int err;
275
276			if (i == cur)
277				continue;
278
279			ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
280				visited, true);
281			if (ret < 0)
282				continue;
283
284			err = uac_clock_selector_set_val(chip, entity_id, i);
285			if (err < 0)
286				continue;
287
288			usb_audio_info(chip,
289				 "found and selected valid clock source %d\n",
290				 ret);
291			return ret;
292		}
293
294		return -ENXIO;
295	}
296
297	/* FIXME: multipliers only act as pass-thru element for now */
298	multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
299	if (multiplier)
300		return __uac_clock_find_source(chip, multiplier->bCSourceID,
301						visited, validate);
302
303	return -EINVAL;
304}
305
306static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
307				   unsigned long *visited, bool validate)
308{
309	struct uac3_clock_source_descriptor *source;
310	struct uac3_clock_selector_descriptor *selector;
311	struct uac3_clock_multiplier_descriptor *multiplier;
312
313	entity_id &= 0xff;
314
315	if (test_and_set_bit(entity_id, visited)) {
316		usb_audio_warn(chip,
317			 "%s(): recursive clock topology detected, id %d.\n",
318			 __func__, entity_id);
319		return -EINVAL;
320	}
321
322	/* first, see if the ID we're looking for is a clock source already */
323	source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
324	if (source) {
325		entity_id = source->bClockID;
326		if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
327								entity_id)) {
328			usb_audio_err(chip,
329				"clock source %d is not valid, cannot use\n",
330				entity_id);
331			return -ENXIO;
332		}
333		return entity_id;
334	}
335
336	selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
337	if (selector) {
338		int ret, i, cur;
339
340		/* the entity ID we are looking for is a selector.
341		 * find out what it currently selects */
342		ret = uac_clock_selector_get_val(chip, selector->bClockID);
343		if (ret < 0)
344			return ret;
 
 
 
345
346		/* Selector values are one-based */
347
348		if (ret > selector->bNrInPins || ret < 1) {
349			usb_audio_err(chip,
350				"%s(): selector reported illegal value, id %d, ret %d\n",
351				__func__, selector->bClockID, ret);
352
353			return -EINVAL;
 
 
354		}
355
 
356		cur = ret;
357		ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
358					       visited, validate);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
359		if (!validate || ret > 0 || !chip->autoclock)
360			return ret;
361
362		/* The current clock source is invalid, try others. */
363		for (i = 1; i <= selector->bNrInPins; i++) {
364			int err;
365
 
 
366			if (i == cur)
367				continue;
368
369			ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
370				visited, true);
 
371			if (ret < 0)
372				continue;
373
374			err = uac_clock_selector_set_val(chip, entity_id, i);
375			if (err < 0)
376				continue;
377
378			usb_audio_info(chip,
379				 "found and selected valid clock source %d\n",
380				 ret);
381			return ret;
382		}
383
384		return -ENXIO;
385	}
386
387	/* FIXME: multipliers only act as pass-thru element for now */
388	multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
389						      entity_id);
390	if (multiplier)
391		return __uac3_clock_find_source(chip, multiplier->bCSourceID,
392						visited, validate);
 
393
394	return -EINVAL;
395}
396
397/*
398 * For all kinds of sample rate settings and other device queries,
399 * the clock source (end-leaf) must be used. However, clock selectors,
400 * clock multipliers and sample rate converters may be specified as
401 * clock source input to terminal. This functions walks the clock path
402 * to its end and tries to find the source.
403 *
404 * The 'visited' bitfield is used internally to detect recursive loops.
405 *
406 * Returns the clock source UnitID (>=0) on success, or an error.
407 */
408int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
409			      int entity_id, bool validate)
410{
411	DECLARE_BITMAP(visited, 256);
412	memset(visited, 0, sizeof(visited));
413
414	switch (protocol) {
415	case UAC_VERSION_2:
416		return __uac_clock_find_source(chip, entity_id, visited,
417					       validate);
418	case UAC_VERSION_3:
419		return __uac3_clock_find_source(chip, entity_id, visited,
420					       validate);
421	default:
422		return -EINVAL;
423	}
424}
425
426static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
427			      struct usb_host_interface *alts,
428			      struct audioformat *fmt, int rate)
429{
430	struct usb_device *dev = chip->dev;
431	unsigned int ep;
432	unsigned char data[3];
433	int err, crate;
434
435	if (get_iface_desc(alts)->bNumEndpoints < 1)
436		return -EINVAL;
437	ep = get_endpoint(alts, 0)->bEndpointAddress;
438
439	/* if endpoint doesn't have sampling rate control, bail out */
440	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
441		return 0;
442
443	data[0] = rate;
444	data[1] = rate >> 8;
445	data[2] = rate >> 16;
446	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
447				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
448				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
449				   data, sizeof(data))) < 0) {
 
450		dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
451			iface, fmt->altsetting, rate, ep);
452		return err;
453	}
454
455	/* Don't check the sample rate for devices which we know don't
456	 * support reading */
457	if (snd_usb_get_sample_rate_quirk(chip))
458		return 0;
459	/* the firmware is likely buggy, don't repeat to fail too many times */
460	if (chip->sample_rate_read_error > 2)
461		return 0;
462
463	if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
464				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
465				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
466				   data, sizeof(data))) < 0) {
 
467		dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
468			iface, fmt->altsetting, ep);
469		chip->sample_rate_read_error++;
470		return 0; /* some devices don't support reading */
471	}
472
473	crate = data[0] | (data[1] << 8) | (data[2] << 16);
 
 
 
 
 
 
474	if (crate != rate) {
475		dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
476		// runtime->rate = crate;
477	}
478
479	return 0;
480}
481
482static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
483			      int altsetting, int clock)
484{
485	struct usb_device *dev = chip->dev;
486	__le32 data;
487	int err;
 
488
 
489	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
490			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
491			      UAC2_CS_CONTROL_SAM_FREQ << 8,
492			      snd_usb_ctrl_intf(chip) | (clock << 8),
493			      &data, sizeof(data));
494	if (err < 0) {
495		dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
496			 iface, altsetting, err);
497		return 0;
498	}
499
500	return le32_to_cpu(data);
501}
502
503static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
504			      struct usb_host_interface *alts,
505			      struct audioformat *fmt, int rate)
 
 
 
 
 
 
 
 
 
506{
507	struct usb_device *dev = chip->dev;
508	__le32 data;
509	int err, cur_rate, prev_rate;
510	int clock;
511	bool writeable;
512	u32 bmControls;
 
 
 
 
513
514	clock = snd_usb_clock_find_source(chip, fmt->protocol,
515					  fmt->clock, true);
516	if (clock < 0)
517		return clock;
518
519	prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
520	if (prev_rate == rate)
 
 
 
 
 
 
 
 
 
521		return 0;
522
523	if (fmt->protocol == UAC_VERSION_3) {
524		struct uac3_clock_source_descriptor *cs_desc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
525
526		cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
527		bmControls = le32_to_cpu(cs_desc->bmControls);
528	} else {
529		struct uac_clock_source_descriptor *cs_desc;
530
531		cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
532		bmControls = cs_desc->bmControls;
533	}
534
535	writeable = uac_v2v3_control_is_writeable(bmControls,
536						  UAC2_CS_CONTROL_SAM_FREQ);
537	if (writeable) {
538		data = cpu_to_le32(rate);
539		err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
540				      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
541				      UAC2_CS_CONTROL_SAM_FREQ << 8,
542				      snd_usb_ctrl_intf(chip) | (clock << 8),
543				      &data, sizeof(data));
544		if (err < 0) {
545			usb_audio_err(chip,
546				"%d:%d: cannot set freq %d (v2/v3): err %d\n",
547				iface, fmt->altsetting, rate, err);
548			return err;
549		}
550
551		cur_rate = get_sample_rate_v2v3(chip, iface,
552						fmt->altsetting, clock);
553	} else {
554		cur_rate = prev_rate;
 
 
555	}
556
 
 
 
557	if (cur_rate != rate) {
558		if (!writeable) {
559			usb_audio_warn(chip,
560				 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
561				 iface, fmt->altsetting, rate, cur_rate);
562			return -ENXIO;
563		}
564		usb_audio_dbg(chip,
565			"current rate %d is different from the runtime rate %d\n",
566			cur_rate, rate);
 
567	}
568
569	/* Some devices doesn't respond to sample rate changes while the
570	 * interface is active. */
571	if (rate != prev_rate) {
572		usb_set_interface(dev, iface, 0);
573		snd_usb_set_interface_quirk(dev);
574		usb_set_interface(dev, iface, fmt->altsetting);
575		snd_usb_set_interface_quirk(dev);
 
 
576	}
577
 
 
 
 
578	return 0;
579}
580
581int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
582			     struct usb_host_interface *alts,
583			     struct audioformat *fmt, int rate)
584{
 
 
 
585	switch (fmt->protocol) {
586	case UAC_VERSION_1:
587	default:
588		return set_sample_rate_v1(chip, iface, alts, fmt, rate);
589
590	case UAC_VERSION_2:
591	case UAC_VERSION_3:
592		return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
 
 
 
 
 
 
 
 
593	}
594}
595
v6.13.7
  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	 * MOTU MicroBook IIc
212	 * Sample rate changes takes more than 2 seconds for this device. Clock
213	 * validity request returns false during that period.
214	 */
215	if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
216		count = 0;
217
218		while ((!ret) && (count < 50)) {
219			int err;
220
221			msleep(100);
222
223			err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
224					      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
225					      UAC2_CS_CONTROL_CLOCK_VALID << 8,
226					      snd_usb_ctrl_intf(ctrl_intf) | (source_id << 8),
227					      &data, sizeof(data));
228			if (err < 0) {
229				dev_warn(&dev->dev,
230					 "%s(): cannot get clock validity for id %d\n",
231					   __func__, source_id);
232				return false;
233			}
234
235			ret = !!data;
236			count++;
237		}
238	}
239
240	return ret;
241}
242
243static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
244				      const struct audioformat *fmt,
245				      int source_id)
246{
247	int err;
248	unsigned char data;
249	struct usb_device *dev = chip->dev;
250	u32 bmControls;
251	union uac23_clock_source_desc *cs_desc;
252	struct usb_host_interface *ctrl_intf;
253
254	ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
255	cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
256	if (!cs_desc)
257		return false;
258
259	if (fmt->protocol == UAC_VERSION_3)
260		bmControls = le32_to_cpu(cs_desc->v3.bmControls);
261	else
262		bmControls = cs_desc->v2.bmControls;
 
 
 
 
 
 
263
264	/* If a clock source can't tell us whether it's valid, we assume it is */
265	if (!uac_v2v3_control_is_readable(bmControls,
266				      UAC2_CS_CONTROL_CLOCK_VALID))
267		return true;
268
269	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
270			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
271			      UAC2_CS_CONTROL_CLOCK_VALID << 8,
272			      snd_usb_ctrl_intf(ctrl_intf) | (source_id << 8),
273			      &data, sizeof(data));
274
275	if (err < 0) {
276		dev_warn(&dev->dev,
277			 "%s(): cannot get clock validity for id %d\n",
278			   __func__, source_id);
279		return false;
280	}
281
282	if (data)
283		return true;
284	else
285		return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
286}
287
288static int __uac_clock_find_source(struct snd_usb_audio *chip,
289				   const struct audioformat *fmt, int entity_id,
290				   unsigned long *visited, bool validate)
291{
292	union uac23_clock_source_desc *source;
293	union uac23_clock_selector_desc *selector;
294	union uac23_clock_multiplier_desc *multiplier;
295	int ret, i, cur, err, pins, clock_id;
296	const u8 *sources;
297	int proto = fmt->protocol;
298	bool readable, writeable;
299	u32 bmControls;
300
301	entity_id &= 0xff;
302
303	if (test_and_set_bit(entity_id, visited)) {
304		usb_audio_warn(chip,
305			 "%s(): recursive clock topology detected, id %d.\n",
306			 __func__, entity_id);
307		return -EINVAL;
308	}
309
310	/* first, see if the ID we're looking at is a clock source already */
311	source = snd_usb_find_clock_source(chip, entity_id, fmt);
312	if (source) {
313		entity_id = GET_VAL(source, proto, bClockID);
314		if (validate && !uac_clock_source_is_valid(chip, fmt,
315								entity_id)) {
316			usb_audio_err(chip,
317				"clock source %d is not valid, cannot use\n",
318				entity_id);
319			return -ENXIO;
320		}
321		return entity_id;
322	}
323
324	selector = snd_usb_find_clock_selector(chip, entity_id, fmt);
325	if (selector) {
326		pins = GET_VAL(selector, proto, bNrInPins);
327		clock_id = GET_VAL(selector, proto, bClockID);
328		sources = GET_VAL(selector, proto, baCSourceID);
329		cur = 0;
330
331		if (proto == UAC_VERSION_3)
332			bmControls = le32_to_cpu(*(__le32 *)(&selector->v3.baCSourceID[0] + pins));
333		else
334			bmControls = *(__u8 *)(&selector->v2.baCSourceID[0] + pins);
335
336		readable = uac_v2v3_control_is_readable(bmControls,
337							UAC2_CX_CLOCK_SELECTOR);
338		writeable = uac_v2v3_control_is_writeable(bmControls,
339							  UAC2_CX_CLOCK_SELECTOR);
340
341		if (pins == 1) {
342			ret = 1;
343			goto find_source;
344		}
345
346		/* for now just warn about buggy device */
347		if (!readable)
348			usb_audio_warn(chip,
349				"%s(): clock selector control is not readable, id %d\n",
350				__func__, clock_id);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
351
352		/* the entity ID we are looking at is a selector.
353		 * find out what it currently selects */
354		ret = uac_clock_selector_get_val(chip, clock_id, fmt->iface);
355		if (ret < 0) {
356			if (!chip->autoclock)
357				return ret;
358			goto find_others;
359		}
360
361		/* Selector values are one-based */
362
363		if (ret > pins || ret < 1) {
364			usb_audio_err(chip,
365				"%s(): selector reported illegal value, id %d, ret %d\n",
366				__func__, clock_id, ret);
367
368			if (!chip->autoclock)
369				return -EINVAL;
370			goto find_others;
371		}
372
373	find_source:
374		cur = ret;
375		ret = __uac_clock_find_source(chip, fmt,
376					      sources[ret - 1],
377					      visited, validate);
378		if (ret > 0) {
379			/* Skip setting clock selector again for some devices */
380			if (chip->quirk_flags & QUIRK_FLAG_SKIP_CLOCK_SELECTOR ||
381			    !writeable)
382				return ret;
383			err = uac_clock_selector_set_val(chip, entity_id, cur, fmt->iface);
384			if (err < 0) {
385				if (pins == 1) {
386					usb_audio_dbg(chip,
387						      "%s(): selector returned an error, "
388						      "assuming a firmware bug, id %d, ret %d\n",
389						      __func__, clock_id, err);
390					return ret;
391				}
392				return err;
393			}
394		}
395
396		if (!validate || ret > 0 || !chip->autoclock)
397			return ret;
398
399	find_others:
400		if (!writeable)
401			return -ENXIO;
402
403		/* The current clock source is invalid, try others. */
404		for (i = 1; i <= pins; i++) {
405			if (i == cur)
406				continue;
407
408			ret = __uac_clock_find_source(chip, fmt,
409						      sources[i - 1],
410						      visited, true);
411			if (ret < 0)
412				continue;
413
414			err = uac_clock_selector_set_val(chip, entity_id, i, fmt->iface);
415			if (err < 0)
416				continue;
417
418			usb_audio_info(chip,
419				 "found and selected valid clock source %d\n",
420				 ret);
421			return ret;
422		}
423
424		return -ENXIO;
425	}
426
427	/* FIXME: multipliers only act as pass-thru element for now */
428	multiplier = snd_usb_find_clock_multiplier(chip, entity_id, fmt);
 
429	if (multiplier)
430		return __uac_clock_find_source(chip, fmt,
431					       GET_VAL(multiplier, proto, bCSourceID),
432					       visited, validate);
433
434	return -EINVAL;
435}
436
437/*
438 * For all kinds of sample rate settings and other device queries,
439 * the clock source (end-leaf) must be used. However, clock selectors,
440 * clock multipliers and sample rate converters may be specified as
441 * clock source input to terminal. This functions walks the clock path
442 * to its end and tries to find the source.
443 *
444 * The 'visited' bitfield is used internally to detect recursive loops.
445 *
446 * Returns the clock source UnitID (>=0) on success, or an error.
447 */
448int snd_usb_clock_find_source(struct snd_usb_audio *chip,
449			      const struct audioformat *fmt, bool validate)
450{
451	DECLARE_BITMAP(visited, 256);
452	memset(visited, 0, sizeof(visited));
453
454	switch (fmt->protocol) {
455	case UAC_VERSION_2:
 
 
456	case UAC_VERSION_3:
457		return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
458					       validate);
459	default:
460		return -EINVAL;
461	}
462}
463
464static int set_sample_rate_v1(struct snd_usb_audio *chip,
465			      const struct audioformat *fmt, int rate)
 
466{
467	struct usb_device *dev = chip->dev;
 
468	unsigned char data[3];
469	int err, crate;
470
 
 
 
 
471	/* if endpoint doesn't have sampling rate control, bail out */
472	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
473		return 0;
474
475	data[0] = rate;
476	data[1] = rate >> 8;
477	data[2] = rate >> 16;
478	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
479			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
480			      UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
481			      fmt->endpoint, data, sizeof(data));
482	if (err < 0) {
483		dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
484			fmt->iface, fmt->altsetting, rate, fmt->endpoint);
485		return err;
486	}
487
488	/* Don't check the sample rate for devices which we know don't
489	 * support reading */
490	if (chip->quirk_flags & QUIRK_FLAG_GET_SAMPLE_RATE)
491		return 0;
492	/* the firmware is likely buggy, don't repeat to fail too many times */
493	if (chip->sample_rate_read_error > 2)
494		return 0;
495
496	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
497			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
498			      UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
499			      fmt->endpoint, data, sizeof(data));
500	if (err < 0) {
501		dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
502			fmt->iface, fmt->altsetting, fmt->endpoint);
503		chip->sample_rate_read_error++;
504		return 0; /* some devices don't support reading */
505	}
506
507	crate = data[0] | (data[1] << 8) | (data[2] << 16);
508	if (!crate) {
509		dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
510		chip->sample_rate_read_error = 3; /* three strikes, see above */
511		return 0;
512	}
513
514	if (crate != rate) {
515		dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
516		// runtime->rate = crate;
517	}
518
519	return 0;
520}
521
522static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
523			      int altsetting, int clock)
524{
525	struct usb_device *dev = chip->dev;
526	__le32 data;
527	int err;
528	struct usb_host_interface *ctrl_intf;
529
530	ctrl_intf = snd_usb_find_ctrl_interface(chip, iface);
531	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
532			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
533			      UAC2_CS_CONTROL_SAM_FREQ << 8,
534			      snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
535			      &data, sizeof(data));
536	if (err < 0) {
537		dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
538			 iface, altsetting, err);
539		return 0;
540	}
541
542	return le32_to_cpu(data);
543}
544
545/*
546 * Try to set the given sample rate:
547 *
548 * Return 0 if the clock source is read-only, the actual rate on success,
549 * or a negative error code.
550 *
551 * This function gets called from format.c to validate each sample rate, too.
552 * Hence no message is shown upon error
553 */
554int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
555				 const struct audioformat *fmt,
556				 int clock, int rate)
557{
 
 
 
 
558	bool writeable;
559	u32 bmControls;
560	__le32 data;
561	int err;
562	union uac23_clock_source_desc *cs_desc;
563	struct usb_host_interface *ctrl_intf;
564
565	ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
566	cs_desc = snd_usb_find_clock_source(chip, clock, fmt);
 
 
567
568	if (!cs_desc)
569		return 0;
570
571	if (fmt->protocol == UAC_VERSION_3)
572		bmControls = le32_to_cpu(cs_desc->v3.bmControls);
573	else
574		bmControls = cs_desc->v2.bmControls;
575
576	writeable = uac_v2v3_control_is_writeable(bmControls,
577						  UAC2_CS_CONTROL_SAM_FREQ);
578	if (!writeable)
579		return 0;
580
581	data = cpu_to_le32(rate);
582	err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
583			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
584			      UAC2_CS_CONTROL_SAM_FREQ << 8,
585			      snd_usb_ctrl_intf(ctrl_intf) | (clock << 8),
586			      &data, sizeof(data));
587	if (err < 0)
588		return err;
589
590	return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
591}
592
593static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
594				const struct audioformat *fmt, int rate)
595{
596	int cur_rate, prev_rate;
597	int clock;
598
599	/* First, try to find a valid clock. This may trigger
600	 * automatic clock selection if the current clock is not
601	 * valid.
602	 */
603	clock = snd_usb_clock_find_source(chip, fmt, true);
604	if (clock < 0) {
605		/* We did not find a valid clock, but that might be
606		 * because the current sample rate does not match an
607		 * external clock source. Try again without validation
608		 * and we will do another validation after setting the
609		 * rate.
610		 */
611		clock = snd_usb_clock_find_source(chip, fmt, false);
612
613		/* Hardcoded sample rates */
614		if (chip->quirk_flags & QUIRK_FLAG_IGNORE_CLOCK_SOURCE)
615			return 0;
 
616
617		if (clock < 0)
618			return clock;
619	}
620
621	prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
622	if (prev_rate == rate)
623		goto validation;
 
 
 
 
 
 
 
 
 
 
 
 
624
625	cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
626	if (cur_rate < 0) {
627		usb_audio_err(chip,
628			      "%d:%d: cannot set freq %d (v2/v3): err %d\n",
629			      fmt->iface, fmt->altsetting, rate, cur_rate);
630		return cur_rate;
631	}
632
633	if (!cur_rate)
634		cur_rate = prev_rate;
635
636	if (cur_rate != rate) {
 
 
 
 
 
 
637		usb_audio_dbg(chip,
638			      "%d:%d: freq mismatch: req %d, clock runs @%d\n",
639			      fmt->iface, fmt->altsetting, rate, cur_rate);
640		/* continue processing */
641	}
642
643	/* FIXME - TEAC devices require the immediate interface setup */
644	if (USB_ID_VENDOR(chip->usb_id) == 0x0644) {
645		bool cur_base_48k = (rate % 48000 == 0);
646		bool prev_base_48k = (prev_rate % 48000 == 0);
647		if (cur_base_48k != prev_base_48k) {
648			usb_set_interface(chip->dev, fmt->iface, fmt->altsetting);
649			if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
650				msleep(50);
651		}
652	}
653
654validation:
655	/* validate clock after rate change */
656	if (!uac_clock_source_is_valid(chip, fmt, clock))
657		return -ENXIO;
658	return 0;
659}
660
661int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
662			     const struct audioformat *fmt, int rate)
 
663{
664	usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
665		      fmt->iface, fmt->altsetting, rate, fmt->clock);
666
667	switch (fmt->protocol) {
668	case UAC_VERSION_1:
669	default:
670		return set_sample_rate_v1(chip, fmt, rate);
671
 
672	case UAC_VERSION_3:
673		if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
674			if (rate != UAC3_BADD_SAMPLING_RATE)
675				return -ENXIO;
676			else
677				return 0;
678		}
679		fallthrough;
680	case UAC_VERSION_2:
681		return set_sample_rate_v2v3(chip, fmt, rate);
682	}
683}
684