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v5.9
  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
v3.15
 
  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#include "quirks.h"
 36
 37static struct uac_clock_source_descriptor *
 38	snd_usb_find_clock_source(struct usb_host_interface *ctrl_iface,
 39				  int clock_id)
 40{
 41	struct uac_clock_source_descriptor *cs = NULL;
 42
 43	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
 44					     ctrl_iface->extralen,
 45					     cs, UAC2_CLOCK_SOURCE))) {
 46		if (cs->bClockID == clock_id)
 47			return cs;
 48	}
 49
 50	return NULL;
 51}
 52
 53static struct uac_clock_selector_descriptor *
 54	snd_usb_find_clock_selector(struct usb_host_interface *ctrl_iface,
 55				    int clock_id)
 56{
 57	struct uac_clock_selector_descriptor *cs = NULL;
 58
 59	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
 60					     ctrl_iface->extralen,
 61					     cs, UAC2_CLOCK_SELECTOR))) {
 62		if (cs->bClockID == clock_id)
 63			return cs;
 64	}
 
 
 
 
 
 
 
 
 
 
 
 65
 66	return NULL;
 
 
 
 67}
 68
 69static struct uac_clock_multiplier_descriptor *
 70	snd_usb_find_clock_multiplier(struct usb_host_interface *ctrl_iface,
 71				      int clock_id)
 72{
 73	struct uac_clock_multiplier_descriptor *cs = NULL;
 74
 75	while ((cs = snd_usb_find_csint_desc(ctrl_iface->extra,
 76					     ctrl_iface->extralen,
 77					     cs, UAC2_CLOCK_MULTIPLIER))) {
 78		if (cs->bClockID == clock_id)
 79			return cs;
 80	}
 81
 82	return NULL;
 
 
 
 83}
 84
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 85static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
 86{
 87	unsigned char buf;
 88	int ret;
 89
 90	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
 91			      UAC2_CS_CUR,
 92			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
 93			      UAC2_CX_CLOCK_SELECTOR << 8,
 94			      snd_usb_ctrl_intf(chip) | (selector_id << 8),
 95			      &buf, sizeof(buf));
 96
 97	if (ret < 0)
 98		return ret;
 99
100	return buf;
101}
102
103static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
104					unsigned char pin)
105{
106	int ret;
107
108	ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
109			      UAC2_CS_CUR,
110			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
111			      UAC2_CX_CLOCK_SELECTOR << 8,
112			      snd_usb_ctrl_intf(chip) | (selector_id << 8),
113			      &pin, sizeof(pin));
114	if (ret < 0)
115		return ret;
116
117	if (ret != sizeof(pin)) {
118		usb_audio_err(chip,
119			"setting selector (id %d) unexpected length %d\n",
120			selector_id, ret);
121		return -EINVAL;
122	}
123
124	ret = uac_clock_selector_get_val(chip, selector_id);
125	if (ret < 0)
126		return ret;
127
128	if (ret != pin) {
129		usb_audio_err(chip,
130			"setting selector (id %d) to %x failed (current: %d)\n",
131			selector_id, pin, ret);
132		return -EINVAL;
133	}
134
135	return ret;
136}
137
138static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
139{
140	int err;
141	unsigned char data;
142	struct usb_device *dev = chip->dev;
143	struct uac_clock_source_descriptor *cs_desc =
144		snd_usb_find_clock_source(chip->ctrl_intf, source_id);
145
146	if (!cs_desc)
147		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
148
149	/* If a clock source can't tell us whether it's valid, we assume it is */
150	if (!uac2_control_is_readable(cs_desc->bmControls,
151				      UAC2_CS_CONTROL_CLOCK_VALID - 1))
152		return 1;
153
154	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
155			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
156			      UAC2_CS_CONTROL_CLOCK_VALID << 8,
157			      snd_usb_ctrl_intf(chip) | (source_id << 8),
158			      &data, sizeof(data));
159
160	if (err < 0) {
161		dev_warn(&dev->dev,
162			 "%s(): cannot get clock validity for id %d\n",
163			   __func__, source_id);
164		return 0;
165	}
166
167	return !!data;
 
 
 
168}
169
170static int __uac_clock_find_source(struct snd_usb_audio *chip,
171				   int entity_id, unsigned long *visited,
172				   bool validate)
173{
174	struct uac_clock_source_descriptor *source;
175	struct uac_clock_selector_descriptor *selector;
176	struct uac_clock_multiplier_descriptor *multiplier;
177
178	entity_id &= 0xff;
179
180	if (test_and_set_bit(entity_id, visited)) {
181		usb_audio_warn(chip,
182			 "%s(): recursive clock topology detected, id %d.\n",
183			 __func__, entity_id);
184		return -EINVAL;
185	}
186
187	/* first, see if the ID we're looking for is a clock source already */
188	source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
189	if (source) {
190		entity_id = source->bClockID;
191		if (validate && !uac_clock_source_is_valid(chip, entity_id)) {
 
192			usb_audio_err(chip,
193				"clock source %d is not valid, cannot use\n",
194				entity_id);
195			return -ENXIO;
196		}
197		return entity_id;
198	}
199
200	selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
201	if (selector) {
202		int ret, i, cur;
203
204		/* the entity ID we are looking for is a selector.
205		 * find out what it currently selects */
206		ret = uac_clock_selector_get_val(chip, selector->bClockID);
207		if (ret < 0)
208			return ret;
209
210		/* Selector values are one-based */
211
212		if (ret > selector->bNrInPins || ret < 1) {
213			usb_audio_err(chip,
214				"%s(): selector reported illegal value, id %d, ret %d\n",
215				__func__, selector->bClockID, ret);
216
217			return -EINVAL;
218		}
219
220		cur = ret;
221		ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
222					       visited, validate);
223		if (!validate || ret > 0 || !chip->autoclock)
224			return ret;
225
226		/* The current clock source is invalid, try others. */
227		for (i = 1; i <= selector->bNrInPins; i++) {
228			int err;
229
230			if (i == cur)
231				continue;
232
233			ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
234				visited, true);
 
235			if (ret < 0)
236				continue;
237
238			err = uac_clock_selector_set_val(chip, entity_id, i);
239			if (err < 0)
240				continue;
241
242			usb_audio_info(chip,
243				 "found and selected valid clock source %d\n",
244				 ret);
245			return ret;
246		}
247
248		return -ENXIO;
249	}
250
251	/* FIXME: multipliers only act as pass-thru element for now */
252	multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
 
253	if (multiplier)
254		return __uac_clock_find_source(chip, multiplier->bCSourceID,
 
255						visited, validate);
256
257	return -EINVAL;
258}
259
260/*
261 * For all kinds of sample rate settings and other device queries,
262 * the clock source (end-leaf) must be used. However, clock selectors,
263 * clock multipliers and sample rate converters may be specified as
264 * clock source input to terminal. This functions walks the clock path
265 * to its end and tries to find the source.
266 *
267 * The 'visited' bitfield is used internally to detect recursive loops.
268 *
269 * Returns the clock source UnitID (>=0) on success, or an error.
270 */
271int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id,
272			      bool validate)
273{
274	DECLARE_BITMAP(visited, 256);
275	memset(visited, 0, sizeof(visited));
276	return __uac_clock_find_source(chip, entity_id, visited, validate);
 
 
 
 
 
 
 
 
 
 
277}
278
279static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
280			      struct usb_host_interface *alts,
281			      struct audioformat *fmt, int rate)
282{
283	struct usb_device *dev = chip->dev;
284	unsigned int ep;
285	unsigned char data[3];
286	int err, crate;
287
 
 
288	ep = get_endpoint(alts, 0)->bEndpointAddress;
289
290	/* if endpoint doesn't have sampling rate control, bail out */
291	if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
292		return 0;
293
294	data[0] = rate;
295	data[1] = rate >> 8;
296	data[2] = rate >> 16;
297	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
298				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
299				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
300				   data, sizeof(data))) < 0) {
 
301		dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
302			iface, fmt->altsetting, rate, ep);
303		return err;
304	}
305
306	if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
307				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
308				   UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
309				   data, sizeof(data))) < 0) {
 
 
 
 
 
 
 
 
 
310		dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
311			iface, fmt->altsetting, ep);
 
312		return 0; /* some devices don't support reading */
313	}
314
315	crate = data[0] | (data[1] << 8) | (data[2] << 16);
316	if (crate != rate) {
317		dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
318		// runtime->rate = crate;
319	}
320
321	return 0;
322}
323
324static int get_sample_rate_v2(struct snd_usb_audio *chip, int iface,
325			      int altsetting, int clock)
326{
327	struct usb_device *dev = chip->dev;
328	__le32 data;
329	int err;
330
331	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
332			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
333			      UAC2_CS_CONTROL_SAM_FREQ << 8,
334			      snd_usb_ctrl_intf(chip) | (clock << 8),
335			      &data, sizeof(data));
336	if (err < 0) {
337		dev_warn(&dev->dev, "%d:%d: cannot get freq (v2): err %d\n",
338			 iface, altsetting, err);
339		return 0;
340	}
341
342	return le32_to_cpu(data);
343}
344
345static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
346			      struct usb_host_interface *alts,
347			      struct audioformat *fmt, int rate)
348{
349	struct usb_device *dev = chip->dev;
350	__le32 data;
351	int err, cur_rate, prev_rate;
352	int clock;
353	bool writeable;
354	struct uac_clock_source_descriptor *cs_desc;
355
356	clock = snd_usb_clock_find_source(chip, fmt->clock, true);
357	if (clock < 0)
358		return clock;
 
 
 
 
 
 
 
 
 
 
 
 
 
359
360	prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
361	if (prev_rate == rate)
362		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
363
364	cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
365	writeable = uac2_control_is_writeable(cs_desc->bmControls, UAC2_CS_CONTROL_SAM_FREQ - 1);
366	if (writeable) {
367		data = cpu_to_le32(rate);
368		err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
369				      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
370				      UAC2_CS_CONTROL_SAM_FREQ << 8,
371				      snd_usb_ctrl_intf(chip) | (clock << 8),
372				      &data, sizeof(data));
373		if (err < 0) {
374			usb_audio_err(chip,
375				"%d:%d: cannot set freq %d (v2): err %d\n",
376				iface, fmt->altsetting, rate, err);
377			return err;
378		}
379
380		cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
 
381	} else {
382		cur_rate = prev_rate;
383	}
384
385	if (cur_rate != rate) {
386		if (!writeable) {
387			usb_audio_warn(chip,
388				 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
389				 iface, fmt->altsetting, rate, cur_rate);
390			return -ENXIO;
391		}
392		usb_audio_dbg(chip,
393			"current rate %d is different from the runtime rate %d\n",
394			cur_rate, rate);
395	}
396
397	/* Some devices doesn't respond to sample rate changes while the
398	 * interface is active. */
399	if (rate != prev_rate) {
400		usb_set_interface(dev, iface, 0);
401		snd_usb_set_interface_quirk(dev);
402		usb_set_interface(dev, iface, fmt->altsetting);
403		snd_usb_set_interface_quirk(dev);
404	}
405
 
 
 
 
406	return 0;
407}
408
409int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
410			     struct usb_host_interface *alts,
411			     struct audioformat *fmt, int rate)
412{
413	switch (fmt->protocol) {
414	case UAC_VERSION_1:
415	default:
416		return set_sample_rate_v1(chip, iface, alts, fmt, rate);
417
 
 
 
 
 
 
 
 
418	case UAC_VERSION_2:
419		return set_sample_rate_v2(chip, iface, alts, fmt, rate);
420	}
421}
422