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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Clock domain and sample rate management functions
4 */
5
6#include <linux/bitops.h>
7#include <linux/init.h>
8#include <linux/string.h>
9#include <linux/usb.h>
10#include <linux/usb/audio.h>
11#include <linux/usb/audio-v2.h>
12#include <linux/usb/audio-v3.h>
13
14#include <sound/core.h>
15#include <sound/info.h>
16#include <sound/pcm.h>
17
18#include "usbaudio.h"
19#include "card.h"
20#include "helper.h"
21#include "clock.h"
22#include "quirks.h"
23
24union uac23_clock_source_desc {
25 struct uac_clock_source_descriptor v2;
26 struct uac3_clock_source_descriptor v3;
27};
28
29union uac23_clock_selector_desc {
30 struct uac_clock_selector_descriptor v2;
31 struct uac3_clock_selector_descriptor v3;
32};
33
34union uac23_clock_multiplier_desc {
35 struct uac_clock_multiplier_descriptor v2;
36 struct uac_clock_multiplier_descriptor v3;
37};
38
39/* check whether the descriptor bLength has the minimal length */
40#define DESC_LENGTH_CHECK(p, proto) \
41 ((proto) == UAC_VERSION_3 ? \
42 ((p)->v3.bLength >= sizeof((p)->v3)) : \
43 ((p)->v2.bLength >= sizeof((p)->v2)))
44
45#define GET_VAL(p, proto, field) \
46 ((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
47
48static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
49 bool (*validator)(void *, int, int),
50 u8 type, int proto)
51{
52 void *cs = NULL;
53
54 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
55 cs, type))) {
56 if (validator(cs, id, proto))
57 return cs;
58 }
59
60 return NULL;
61}
62
63static bool validate_clock_source(void *p, int id, int proto)
64{
65 union uac23_clock_source_desc *cs = p;
66
67 if (!DESC_LENGTH_CHECK(cs, proto))
68 return false;
69 return GET_VAL(cs, proto, bClockID) == id;
70}
71
72static bool validate_clock_selector(void *p, int id, int proto)
73{
74 union uac23_clock_selector_desc *cs = p;
75
76 if (!DESC_LENGTH_CHECK(cs, proto))
77 return false;
78 if (GET_VAL(cs, proto, bClockID) != id)
79 return false;
80 /* additional length check for baCSourceID array (in bNrInPins size)
81 * and two more fields (which sizes depend on the protocol)
82 */
83 if (proto == UAC_VERSION_3)
84 return cs->v3.bLength >= sizeof(cs->v3) + cs->v3.bNrInPins +
85 4 /* bmControls */ + 2 /* wCSelectorDescrStr */;
86 else
87 return cs->v2.bLength >= sizeof(cs->v2) + cs->v2.bNrInPins +
88 1 /* bmControls */ + 1 /* iClockSelector */;
89}
90
91static bool validate_clock_multiplier(void *p, int id, int proto)
92{
93 union uac23_clock_multiplier_desc *cs = p;
94
95 if (!DESC_LENGTH_CHECK(cs, proto))
96 return false;
97 return GET_VAL(cs, proto, bClockID) == id;
98}
99
100#define DEFINE_FIND_HELPER(name, obj, validator, type2, type3) \
101static obj *name(struct snd_usb_audio *chip, int id, \
102 const struct audioformat *fmt) \
103{ \
104 struct usb_host_interface *ctrl_intf = \
105 snd_usb_find_ctrl_interface(chip, fmt->iface); \
106 return find_uac_clock_desc(ctrl_intf, id, validator, \
107 fmt->protocol == UAC_VERSION_3 ? (type3) : (type2), \
108 fmt->protocol); \
109}
110
111DEFINE_FIND_HELPER(snd_usb_find_clock_source,
112 union uac23_clock_source_desc, validate_clock_source,
113 UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
114DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
115 union uac23_clock_selector_desc, validate_clock_selector,
116 UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
117DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
118 union uac23_clock_multiplier_desc, validate_clock_multiplier,
119 UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
120
121static int uac_clock_selector_get_val(struct snd_usb_audio *chip,
122 int selector_id, int iface_no)
123{
124 struct usb_host_interface *ctrl_intf;
125 unsigned char buf;
126 int ret;
127
128 ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
129 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
130 UAC2_CS_CUR,
131 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
132 UAC2_CX_CLOCK_SELECTOR << 8,
133 snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
134 &buf, sizeof(buf));
135
136 if (ret < 0)
137 return ret;
138
139 return buf;
140}
141
142static int uac_clock_selector_set_val(struct snd_usb_audio *chip,
143 int selector_id, unsigned char pin, int iface_no)
144{
145 struct usb_host_interface *ctrl_intf;
146 int ret;
147
148 ctrl_intf = snd_usb_find_ctrl_interface(chip, iface_no);
149 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
150 UAC2_CS_CUR,
151 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
152 UAC2_CX_CLOCK_SELECTOR << 8,
153 snd_usb_ctrl_intf(ctrl_intf) | (selector_id << 8),
154 &pin, sizeof(pin));
155 if (ret < 0)
156 return ret;
157
158 if (ret != sizeof(pin)) {
159 usb_audio_err(chip,
160 "setting selector (id %d) unexpected length %d\n",
161 selector_id, ret);
162 return -EINVAL;
163 }
164
165 ret = uac_clock_selector_get_val(chip, selector_id, iface_no);
166 if (ret < 0)
167 return ret;
168
169 if (ret != pin) {
170 usb_audio_err(chip,
171 "setting selector (id %d) to %x failed (current: %d)\n",
172 selector_id, pin, ret);
173 return -EINVAL;
174 }
175
176 return ret;
177}
178
179static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
180 const struct audioformat *fmt,
181 int source_id)
182{
183 bool ret = false;
184 int count;
185 unsigned char data;
186 struct usb_device *dev = chip->dev;
187 union uac23_clock_source_desc *cs_desc;
188 struct usb_host_interface *ctrl_intf;
189
190 ctrl_intf = snd_usb_find_ctrl_interface(chip, fmt->iface);
191 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt);
192 if (!cs_desc)
193 return false;
194
195 if (fmt->protocol == UAC_VERSION_2) {
196 /*
197 * Assume the clock is valid if clock source supports only one
198 * single sample rate, the terminal is connected directly to it
199 * (there is no clock selector) and clock type is internal.
200 * This is to deal with some Denon DJ controllers that always
201 * reports that clock is invalid.
202 */
203 if (fmt->nr_rates == 1 &&
204 (fmt->clock & 0xff) == cs_desc->v2.bClockID &&
205 (cs_desc->v2.bmAttributes & 0x3) !=
206 UAC_CLOCK_SOURCE_TYPE_EXT)
207 return true;
208 }
209
210 /*
211 * 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
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(struct snd_usb_audio *chip,
155 int protocol,
156 int source_id)
157{
158 int err;
159 unsigned char data;
160 struct usb_device *dev = chip->dev;
161 u32 bmControls;
162
163 if (protocol == UAC_VERSION_3) {
164 struct uac3_clock_source_descriptor *cs_desc =
165 snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
166
167 if (!cs_desc)
168 return 0;
169 bmControls = le32_to_cpu(cs_desc->bmControls);
170 } else { /* UAC_VERSION_1/2 */
171 struct uac_clock_source_descriptor *cs_desc =
172 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
173
174 if (!cs_desc)
175 return 0;
176 bmControls = cs_desc->bmControls;
177 }
178
179 /* If a clock source can't tell us whether it's valid, we assume it is */
180 if (!uac_v2v3_control_is_readable(bmControls,
181 UAC2_CS_CONTROL_CLOCK_VALID))
182 return 1;
183
184 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
185 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
186 UAC2_CS_CONTROL_CLOCK_VALID << 8,
187 snd_usb_ctrl_intf(chip) | (source_id << 8),
188 &data, sizeof(data));
189
190 if (err < 0) {
191 dev_warn(&dev->dev,
192 "%s(): cannot get clock validity for id %d\n",
193 __func__, source_id);
194 return 0;
195 }
196
197 return !!data;
198}
199
200static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
201 unsigned long *visited, bool validate)
202{
203 struct uac_clock_source_descriptor *source;
204 struct uac_clock_selector_descriptor *selector;
205 struct uac_clock_multiplier_descriptor *multiplier;
206
207 entity_id &= 0xff;
208
209 if (test_and_set_bit(entity_id, visited)) {
210 usb_audio_warn(chip,
211 "%s(): recursive clock topology detected, id %d.\n",
212 __func__, entity_id);
213 return -EINVAL;
214 }
215
216 /* first, see if the ID we're looking for is a clock source already */
217 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
218 if (source) {
219 entity_id = source->bClockID;
220 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
221 entity_id)) {
222 usb_audio_err(chip,
223 "clock source %d is not valid, cannot use\n",
224 entity_id);
225 return -ENXIO;
226 }
227 return entity_id;
228 }
229
230 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
231 if (selector) {
232 int ret, i, cur;
233
234 /* the entity ID we are looking for is a selector.
235 * find out what it currently selects */
236 ret = uac_clock_selector_get_val(chip, selector->bClockID);
237 if (ret < 0)
238 return ret;
239
240 /* Selector values are one-based */
241
242 if (ret > selector->bNrInPins || ret < 1) {
243 usb_audio_err(chip,
244 "%s(): selector reported illegal value, id %d, ret %d\n",
245 __func__, selector->bClockID, ret);
246
247 return -EINVAL;
248 }
249
250 cur = ret;
251 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
252 visited, validate);
253 if (!validate || ret > 0 || !chip->autoclock)
254 return ret;
255
256 /* The current clock source is invalid, try others. */
257 for (i = 1; i <= selector->bNrInPins; i++) {
258 int err;
259
260 if (i == cur)
261 continue;
262
263 ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
264 visited, true);
265 if (ret < 0)
266 continue;
267
268 err = uac_clock_selector_set_val(chip, entity_id, i);
269 if (err < 0)
270 continue;
271
272 usb_audio_info(chip,
273 "found and selected valid clock source %d\n",
274 ret);
275 return ret;
276 }
277
278 return -ENXIO;
279 }
280
281 /* FIXME: multipliers only act as pass-thru element for now */
282 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
283 if (multiplier)
284 return __uac_clock_find_source(chip, multiplier->bCSourceID,
285 visited, validate);
286
287 return -EINVAL;
288}
289
290static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
291 unsigned long *visited, bool validate)
292{
293 struct uac3_clock_source_descriptor *source;
294 struct uac3_clock_selector_descriptor *selector;
295 struct uac3_clock_multiplier_descriptor *multiplier;
296
297 entity_id &= 0xff;
298
299 if (test_and_set_bit(entity_id, visited)) {
300 usb_audio_warn(chip,
301 "%s(): recursive clock topology detected, id %d.\n",
302 __func__, entity_id);
303 return -EINVAL;
304 }
305
306 /* first, see if the ID we're looking for is a clock source already */
307 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
308 if (source) {
309 entity_id = source->bClockID;
310 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
311 entity_id)) {
312 usb_audio_err(chip,
313 "clock source %d is not valid, cannot use\n",
314 entity_id);
315 return -ENXIO;
316 }
317 return entity_id;
318 }
319
320 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
321 if (selector) {
322 int ret, i, cur;
323
324 /* the entity ID we are looking for is a selector.
325 * find out what it currently selects */
326 ret = uac_clock_selector_get_val(chip, selector->bClockID);
327 if (ret < 0)
328 return ret;
329
330 /* Selector values are one-based */
331
332 if (ret > selector->bNrInPins || ret < 1) {
333 usb_audio_err(chip,
334 "%s(): selector reported illegal value, id %d, ret %d\n",
335 __func__, selector->bClockID, ret);
336
337 return -EINVAL;
338 }
339
340 cur = ret;
341 ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
342 visited, validate);
343 if (!validate || ret > 0 || !chip->autoclock)
344 return ret;
345
346 /* The current clock source is invalid, try others. */
347 for (i = 1; i <= selector->bNrInPins; i++) {
348 int err;
349
350 if (i == cur)
351 continue;
352
353 ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
354 visited, true);
355 if (ret < 0)
356 continue;
357
358 err = uac_clock_selector_set_val(chip, entity_id, i);
359 if (err < 0)
360 continue;
361
362 usb_audio_info(chip,
363 "found and selected valid clock source %d\n",
364 ret);
365 return ret;
366 }
367
368 return -ENXIO;
369 }
370
371 /* FIXME: multipliers only act as pass-thru element for now */
372 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
373 entity_id);
374 if (multiplier)
375 return __uac3_clock_find_source(chip, multiplier->bCSourceID,
376 visited, validate);
377
378 return -EINVAL;
379}
380
381/*
382 * For all kinds of sample rate settings and other device queries,
383 * the clock source (end-leaf) must be used. However, clock selectors,
384 * clock multipliers and sample rate converters may be specified as
385 * clock source input to terminal. This functions walks the clock path
386 * to its end and tries to find the source.
387 *
388 * The 'visited' bitfield is used internally to detect recursive loops.
389 *
390 * Returns the clock source UnitID (>=0) on success, or an error.
391 */
392int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
393 int entity_id, bool validate)
394{
395 DECLARE_BITMAP(visited, 256);
396 memset(visited, 0, sizeof(visited));
397
398 switch (protocol) {
399 case UAC_VERSION_2:
400 return __uac_clock_find_source(chip, entity_id, visited,
401 validate);
402 case UAC_VERSION_3:
403 return __uac3_clock_find_source(chip, entity_id, visited,
404 validate);
405 default:
406 return -EINVAL;
407 }
408}
409
410static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
411 struct usb_host_interface *alts,
412 struct audioformat *fmt, int rate)
413{
414 struct usb_device *dev = chip->dev;
415 unsigned int ep;
416 unsigned char data[3];
417 int err, crate;
418
419 if (get_iface_desc(alts)->bNumEndpoints < 1)
420 return -EINVAL;
421 ep = get_endpoint(alts, 0)->bEndpointAddress;
422
423 /* if endpoint doesn't have sampling rate control, bail out */
424 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
425 return 0;
426
427 data[0] = rate;
428 data[1] = rate >> 8;
429 data[2] = rate >> 16;
430 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
431 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
432 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
433 data, sizeof(data));
434 if (err < 0) {
435 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
436 iface, fmt->altsetting, rate, ep);
437 return err;
438 }
439
440 /* Don't check the sample rate for devices which we know don't
441 * support reading */
442 if (snd_usb_get_sample_rate_quirk(chip))
443 return 0;
444 /* the firmware is likely buggy, don't repeat to fail too many times */
445 if (chip->sample_rate_read_error > 2)
446 return 0;
447
448 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
449 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
450 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
451 data, sizeof(data));
452 if (err < 0) {
453 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
454 iface, fmt->altsetting, ep);
455 chip->sample_rate_read_error++;
456 return 0; /* some devices don't support reading */
457 }
458
459 crate = data[0] | (data[1] << 8) | (data[2] << 16);
460 if (crate != rate) {
461 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
462 // runtime->rate = crate;
463 }
464
465 return 0;
466}
467
468static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
469 int altsetting, int clock)
470{
471 struct usb_device *dev = chip->dev;
472 __le32 data;
473 int err;
474
475 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
476 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
477 UAC2_CS_CONTROL_SAM_FREQ << 8,
478 snd_usb_ctrl_intf(chip) | (clock << 8),
479 &data, sizeof(data));
480 if (err < 0) {
481 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
482 iface, altsetting, err);
483 return 0;
484 }
485
486 return le32_to_cpu(data);
487}
488
489static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
490 struct usb_host_interface *alts,
491 struct audioformat *fmt, int rate)
492{
493 struct usb_device *dev = chip->dev;
494 __le32 data;
495 int err, cur_rate, prev_rate;
496 int clock;
497 bool writeable;
498 u32 bmControls;
499
500 /* First, try to find a valid clock. This may trigger
501 * automatic clock selection if the current clock is not
502 * valid.
503 */
504 clock = snd_usb_clock_find_source(chip, fmt->protocol,
505 fmt->clock, true);
506 if (clock < 0) {
507 /* We did not find a valid clock, but that might be
508 * because the current sample rate does not match an
509 * external clock source. Try again without validation
510 * and we will do another validation after setting the
511 * rate.
512 */
513 clock = snd_usb_clock_find_source(chip, fmt->protocol,
514 fmt->clock, false);
515 if (clock < 0)
516 return clock;
517 }
518
519 prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
520 if (prev_rate == rate)
521 goto validation;
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
578validation:
579 /* validate clock after rate change */
580 if (!uac_clock_source_is_valid(chip, fmt->protocol, clock))
581 return -ENXIO;
582 return 0;
583}
584
585int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
586 struct usb_host_interface *alts,
587 struct audioformat *fmt, int rate)
588{
589 switch (fmt->protocol) {
590 case UAC_VERSION_1:
591 default:
592 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
593
594 case UAC_VERSION_3:
595 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
596 if (rate != UAC3_BADD_SAMPLING_RATE)
597 return -ENXIO;
598 else
599 return 0;
600 }
601 /* fall through */
602 case UAC_VERSION_2:
603 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);
604 }
605}
606