Loading...
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#define GET_VAL(p, proto, field) \
40 ((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
41
42static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
43 bool (*validator)(void *, int, int),
44 u8 type, int proto)
45{
46 void *cs = NULL;
47
48 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
49 cs, type))) {
50 if (validator(cs, id, proto))
51 return cs;
52 }
53
54 return NULL;
55}
56
57static bool validate_clock_source(void *p, int id, int proto)
58{
59 union uac23_clock_source_desc *cs = p;
60
61 return GET_VAL(cs, proto, bClockID) == id;
62}
63
64static bool validate_clock_selector(void *p, int id, int proto)
65{
66 union uac23_clock_selector_desc *cs = p;
67
68 return GET_VAL(cs, proto, bClockID) == id;
69}
70
71static bool validate_clock_multiplier(void *p, int id, int proto)
72{
73 union uac23_clock_multiplier_desc *cs = p;
74
75 return GET_VAL(cs, proto, bClockID) == id;
76}
77
78#define DEFINE_FIND_HELPER(name, obj, validator, type2, type3) \
79static obj *name(struct snd_usb_audio *chip, int id, int proto) \
80{ \
81 return find_uac_clock_desc(chip->ctrl_intf, id, validator, \
82 proto == UAC_VERSION_3 ? (type3) : (type2), \
83 proto); \
84}
85
86DEFINE_FIND_HELPER(snd_usb_find_clock_source,
87 union uac23_clock_source_desc, validate_clock_source,
88 UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
89DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
90 union uac23_clock_selector_desc, validate_clock_selector,
91 UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
92DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
93 union uac23_clock_multiplier_desc, validate_clock_multiplier,
94 UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
95
96static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
97{
98 unsigned char buf;
99 int ret;
100
101 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
102 UAC2_CS_CUR,
103 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
104 UAC2_CX_CLOCK_SELECTOR << 8,
105 snd_usb_ctrl_intf(chip) | (selector_id << 8),
106 &buf, sizeof(buf));
107
108 if (ret < 0)
109 return ret;
110
111 return buf;
112}
113
114static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
115 unsigned char pin)
116{
117 int ret;
118
119 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
120 UAC2_CS_CUR,
121 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
122 UAC2_CX_CLOCK_SELECTOR << 8,
123 snd_usb_ctrl_intf(chip) | (selector_id << 8),
124 &pin, sizeof(pin));
125 if (ret < 0)
126 return ret;
127
128 if (ret != sizeof(pin)) {
129 usb_audio_err(chip,
130 "setting selector (id %d) unexpected length %d\n",
131 selector_id, ret);
132 return -EINVAL;
133 }
134
135 ret = uac_clock_selector_get_val(chip, selector_id);
136 if (ret < 0)
137 return ret;
138
139 if (ret != pin) {
140 usb_audio_err(chip,
141 "setting selector (id %d) to %x failed (current: %d)\n",
142 selector_id, pin, ret);
143 return -EINVAL;
144 }
145
146 return ret;
147}
148
149static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
150 const struct audioformat *fmt,
151 int source_id)
152{
153 bool ret = false;
154 int count;
155 unsigned char data;
156 struct usb_device *dev = chip->dev;
157 union uac23_clock_source_desc *cs_desc;
158
159 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
160 if (!cs_desc)
161 return false;
162
163 if (fmt->protocol == UAC_VERSION_2) {
164 /*
165 * Assume the clock is valid if clock source supports only one
166 * single sample rate, the terminal is connected directly to it
167 * (there is no clock selector) and clock type is internal.
168 * This is to deal with some Denon DJ controllers that always
169 * reports that clock is invalid.
170 */
171 if (fmt->nr_rates == 1 &&
172 (fmt->clock & 0xff) == cs_desc->v2.bClockID &&
173 (cs_desc->v2.bmAttributes & 0x3) !=
174 UAC_CLOCK_SOURCE_TYPE_EXT)
175 return true;
176 }
177
178 /*
179 * MOTU MicroBook IIc
180 * Sample rate changes takes more than 2 seconds for this device. Clock
181 * validity request returns false during that period.
182 */
183 if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
184 count = 0;
185
186 while ((!ret) && (count < 50)) {
187 int err;
188
189 msleep(100);
190
191 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
192 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
193 UAC2_CS_CONTROL_CLOCK_VALID << 8,
194 snd_usb_ctrl_intf(chip) | (source_id << 8),
195 &data, sizeof(data));
196 if (err < 0) {
197 dev_warn(&dev->dev,
198 "%s(): cannot get clock validity for id %d\n",
199 __func__, source_id);
200 return false;
201 }
202
203 ret = !!data;
204 count++;
205 }
206 }
207
208 return ret;
209}
210
211static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
212 const struct audioformat *fmt,
213 int source_id)
214{
215 int err;
216 unsigned char data;
217 struct usb_device *dev = chip->dev;
218 u32 bmControls;
219 union uac23_clock_source_desc *cs_desc;
220
221 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
222 if (!cs_desc)
223 return false;
224
225 if (fmt->protocol == UAC_VERSION_3)
226 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
227 else
228 bmControls = cs_desc->v2.bmControls;
229
230 /* If a clock source can't tell us whether it's valid, we assume it is */
231 if (!uac_v2v3_control_is_readable(bmControls,
232 UAC2_CS_CONTROL_CLOCK_VALID))
233 return true;
234
235 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
236 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
237 UAC2_CS_CONTROL_CLOCK_VALID << 8,
238 snd_usb_ctrl_intf(chip) | (source_id << 8),
239 &data, sizeof(data));
240
241 if (err < 0) {
242 dev_warn(&dev->dev,
243 "%s(): cannot get clock validity for id %d\n",
244 __func__, source_id);
245 return false;
246 }
247
248 if (data)
249 return true;
250 else
251 return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
252}
253
254static int __uac_clock_find_source(struct snd_usb_audio *chip,
255 const struct audioformat *fmt, int entity_id,
256 unsigned long *visited, bool validate)
257{
258 union uac23_clock_source_desc *source;
259 union uac23_clock_selector_desc *selector;
260 union uac23_clock_multiplier_desc *multiplier;
261 int ret, i, cur, err, pins, clock_id;
262 const u8 *sources;
263 int proto = fmt->protocol;
264
265 entity_id &= 0xff;
266
267 if (test_and_set_bit(entity_id, visited)) {
268 usb_audio_warn(chip,
269 "%s(): recursive clock topology detected, id %d.\n",
270 __func__, entity_id);
271 return -EINVAL;
272 }
273
274 /* first, see if the ID we're looking at is a clock source already */
275 source = snd_usb_find_clock_source(chip, entity_id, proto);
276 if (source) {
277 entity_id = GET_VAL(source, proto, bClockID);
278 if (validate && !uac_clock_source_is_valid(chip, fmt,
279 entity_id)) {
280 usb_audio_err(chip,
281 "clock source %d is not valid, cannot use\n",
282 entity_id);
283 return -ENXIO;
284 }
285 return entity_id;
286 }
287
288 selector = snd_usb_find_clock_selector(chip, entity_id, proto);
289 if (selector) {
290 pins = GET_VAL(selector, proto, bNrInPins);
291 clock_id = GET_VAL(selector, proto, bClockID);
292 sources = GET_VAL(selector, proto, baCSourceID);
293 cur = 0;
294
295 if (pins == 1) {
296 ret = 1;
297 goto find_source;
298 }
299
300 /* the entity ID we are looking at is a selector.
301 * find out what it currently selects */
302 ret = uac_clock_selector_get_val(chip, clock_id);
303 if (ret < 0) {
304 if (!chip->autoclock)
305 return ret;
306 goto find_others;
307 }
308
309 /* Selector values are one-based */
310
311 if (ret > pins || ret < 1) {
312 usb_audio_err(chip,
313 "%s(): selector reported illegal value, id %d, ret %d\n",
314 __func__, clock_id, ret);
315
316 if (!chip->autoclock)
317 return -EINVAL;
318 goto find_others;
319 }
320
321 find_source:
322 cur = ret;
323 ret = __uac_clock_find_source(chip, fmt,
324 sources[ret - 1],
325 visited, validate);
326 if (ret > 0) {
327 /* Skip setting clock selector again for some devices */
328 if (chip->quirk_flags & QUIRK_FLAG_SKIP_CLOCK_SELECTOR)
329 return ret;
330 err = uac_clock_selector_set_val(chip, entity_id, cur);
331 if (err < 0)
332 return err;
333 }
334
335 if (!validate || ret > 0 || !chip->autoclock)
336 return ret;
337
338 find_others:
339 /* The current clock source is invalid, try others. */
340 for (i = 1; i <= pins; i++) {
341 if (i == cur)
342 continue;
343
344 ret = __uac_clock_find_source(chip, fmt,
345 sources[i - 1],
346 visited, true);
347 if (ret < 0)
348 continue;
349
350 err = uac_clock_selector_set_val(chip, entity_id, i);
351 if (err < 0)
352 continue;
353
354 usb_audio_info(chip,
355 "found and selected valid clock source %d\n",
356 ret);
357 return ret;
358 }
359
360 return -ENXIO;
361 }
362
363 /* FIXME: multipliers only act as pass-thru element for now */
364 multiplier = snd_usb_find_clock_multiplier(chip, entity_id, proto);
365 if (multiplier)
366 return __uac_clock_find_source(chip, fmt,
367 GET_VAL(multiplier, proto, bCSourceID),
368 visited, validate);
369
370 return -EINVAL;
371}
372
373/*
374 * For all kinds of sample rate settings and other device queries,
375 * the clock source (end-leaf) must be used. However, clock selectors,
376 * clock multipliers and sample rate converters may be specified as
377 * clock source input to terminal. This functions walks the clock path
378 * to its end and tries to find the source.
379 *
380 * The 'visited' bitfield is used internally to detect recursive loops.
381 *
382 * Returns the clock source UnitID (>=0) on success, or an error.
383 */
384int snd_usb_clock_find_source(struct snd_usb_audio *chip,
385 const struct audioformat *fmt, bool validate)
386{
387 DECLARE_BITMAP(visited, 256);
388 memset(visited, 0, sizeof(visited));
389
390 switch (fmt->protocol) {
391 case UAC_VERSION_2:
392 case UAC_VERSION_3:
393 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
394 validate);
395 default:
396 return -EINVAL;
397 }
398}
399
400static int set_sample_rate_v1(struct snd_usb_audio *chip,
401 const struct audioformat *fmt, int rate)
402{
403 struct usb_device *dev = chip->dev;
404 unsigned char data[3];
405 int err, crate;
406
407 /* if endpoint doesn't have sampling rate control, bail out */
408 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
409 return 0;
410
411 data[0] = rate;
412 data[1] = rate >> 8;
413 data[2] = rate >> 16;
414 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
415 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
416 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
417 fmt->endpoint, data, sizeof(data));
418 if (err < 0) {
419 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
420 fmt->iface, fmt->altsetting, rate, fmt->endpoint);
421 return err;
422 }
423
424 /* Don't check the sample rate for devices which we know don't
425 * support reading */
426 if (chip->quirk_flags & QUIRK_FLAG_GET_SAMPLE_RATE)
427 return 0;
428 /* the firmware is likely buggy, don't repeat to fail too many times */
429 if (chip->sample_rate_read_error > 2)
430 return 0;
431
432 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
433 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
434 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
435 fmt->endpoint, data, sizeof(data));
436 if (err < 0) {
437 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
438 fmt->iface, fmt->altsetting, fmt->endpoint);
439 chip->sample_rate_read_error++;
440 return 0; /* some devices don't support reading */
441 }
442
443 crate = data[0] | (data[1] << 8) | (data[2] << 16);
444 if (!crate) {
445 dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
446 chip->sample_rate_read_error = 3; /* three strikes, see above */
447 return 0;
448 }
449
450 if (crate != rate) {
451 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
452 // runtime->rate = crate;
453 }
454
455 return 0;
456}
457
458static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
459 int altsetting, int clock)
460{
461 struct usb_device *dev = chip->dev;
462 __le32 data;
463 int err;
464
465 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
466 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
467 UAC2_CS_CONTROL_SAM_FREQ << 8,
468 snd_usb_ctrl_intf(chip) | (clock << 8),
469 &data, sizeof(data));
470 if (err < 0) {
471 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
472 iface, altsetting, err);
473 return 0;
474 }
475
476 return le32_to_cpu(data);
477}
478
479/*
480 * Try to set the given sample rate:
481 *
482 * Return 0 if the clock source is read-only, the actual rate on success,
483 * or a negative error code.
484 *
485 * This function gets called from format.c to validate each sample rate, too.
486 * Hence no message is shown upon error
487 */
488int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
489 const struct audioformat *fmt,
490 int clock, int rate)
491{
492 bool writeable;
493 u32 bmControls;
494 __le32 data;
495 int err;
496 union uac23_clock_source_desc *cs_desc;
497
498 cs_desc = snd_usb_find_clock_source(chip, clock, fmt->protocol);
499
500 if (!cs_desc)
501 return 0;
502
503 if (fmt->protocol == UAC_VERSION_3)
504 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
505 else
506 bmControls = cs_desc->v2.bmControls;
507
508 writeable = uac_v2v3_control_is_writeable(bmControls,
509 UAC2_CS_CONTROL_SAM_FREQ);
510 if (!writeable)
511 return 0;
512
513 data = cpu_to_le32(rate);
514 err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
515 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
516 UAC2_CS_CONTROL_SAM_FREQ << 8,
517 snd_usb_ctrl_intf(chip) | (clock << 8),
518 &data, sizeof(data));
519 if (err < 0)
520 return err;
521
522 return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
523}
524
525static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
526 const struct audioformat *fmt, int rate)
527{
528 int cur_rate, prev_rate;
529 int clock;
530
531 /* First, try to find a valid clock. This may trigger
532 * automatic clock selection if the current clock is not
533 * valid.
534 */
535 clock = snd_usb_clock_find_source(chip, fmt, true);
536 if (clock < 0) {
537 /* We did not find a valid clock, but that might be
538 * because the current sample rate does not match an
539 * external clock source. Try again without validation
540 * and we will do another validation after setting the
541 * rate.
542 */
543 clock = snd_usb_clock_find_source(chip, fmt, false);
544
545 /* Hardcoded sample rates */
546 if (chip->quirk_flags & QUIRK_FLAG_IGNORE_CLOCK_SOURCE)
547 return 0;
548
549 if (clock < 0)
550 return clock;
551 }
552
553 prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
554 if (prev_rate == rate)
555 goto validation;
556
557 cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
558 if (cur_rate < 0) {
559 usb_audio_err(chip,
560 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
561 fmt->iface, fmt->altsetting, rate, cur_rate);
562 return cur_rate;
563 }
564
565 if (!cur_rate)
566 cur_rate = prev_rate;
567
568 if (cur_rate != rate) {
569 usb_audio_dbg(chip,
570 "%d:%d: freq mismatch: req %d, clock runs @%d\n",
571 fmt->iface, fmt->altsetting, rate, cur_rate);
572 /* continue processing */
573 }
574
575 /* FIXME - TEAC devices require the immediate interface setup */
576 if (USB_ID_VENDOR(chip->usb_id) == 0x0644) {
577 bool cur_base_48k = (rate % 48000 == 0);
578 bool prev_base_48k = (prev_rate % 48000 == 0);
579 if (cur_base_48k != prev_base_48k) {
580 usb_set_interface(chip->dev, fmt->iface, fmt->altsetting);
581 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
582 msleep(50);
583 }
584 }
585
586validation:
587 /* validate clock after rate change */
588 if (!uac_clock_source_is_valid(chip, fmt, clock))
589 return -ENXIO;
590 return 0;
591}
592
593int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
594 const struct audioformat *fmt, int rate)
595{
596 usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
597 fmt->iface, fmt->altsetting, rate, fmt->clock);
598
599 switch (fmt->protocol) {
600 case UAC_VERSION_1:
601 default:
602 return set_sample_rate_v1(chip, fmt, rate);
603
604 case UAC_VERSION_3:
605 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
606 if (rate != UAC3_BADD_SAMPLING_RATE)
607 return -ENXIO;
608 else
609 return 0;
610 }
611 fallthrough;
612 case UAC_VERSION_2:
613 return set_sample_rate_v2v3(chip, fmt, rate);
614 }
615}
616
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 if (get_iface_desc(alts)->bNumEndpoints < 1)
289 return -EINVAL;
290 ep = get_endpoint(alts, 0)->bEndpointAddress;
291
292 /* if endpoint doesn't have sampling rate control, bail out */
293 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
294 return 0;
295
296 data[0] = rate;
297 data[1] = rate >> 8;
298 data[2] = rate >> 16;
299 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
300 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
301 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
302 data, sizeof(data))) < 0) {
303 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
304 iface, fmt->altsetting, rate, ep);
305 return err;
306 }
307
308 /* Don't check the sample rate for devices which we know don't
309 * support reading */
310 if (snd_usb_get_sample_rate_quirk(chip))
311 return 0;
312 /* the firmware is likely buggy, don't repeat to fail too many times */
313 if (chip->sample_rate_read_error > 2)
314 return 0;
315
316 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
317 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
318 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
319 data, sizeof(data))) < 0) {
320 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
321 iface, fmt->altsetting, ep);
322 chip->sample_rate_read_error++;
323 return 0; /* some devices don't support reading */
324 }
325
326 crate = data[0] | (data[1] << 8) | (data[2] << 16);
327 if (crate != rate) {
328 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
329 // runtime->rate = crate;
330 }
331
332 return 0;
333}
334
335static int get_sample_rate_v2(struct snd_usb_audio *chip, int iface,
336 int altsetting, int clock)
337{
338 struct usb_device *dev = chip->dev;
339 __le32 data;
340 int err;
341
342 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
343 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
344 UAC2_CS_CONTROL_SAM_FREQ << 8,
345 snd_usb_ctrl_intf(chip) | (clock << 8),
346 &data, sizeof(data));
347 if (err < 0) {
348 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2): err %d\n",
349 iface, altsetting, err);
350 return 0;
351 }
352
353 return le32_to_cpu(data);
354}
355
356static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface,
357 struct usb_host_interface *alts,
358 struct audioformat *fmt, int rate)
359{
360 struct usb_device *dev = chip->dev;
361 __le32 data;
362 int err, cur_rate, prev_rate;
363 int clock;
364 bool writeable;
365 struct uac_clock_source_descriptor *cs_desc;
366
367 clock = snd_usb_clock_find_source(chip, fmt->clock, true);
368 if (clock < 0)
369 return clock;
370
371 prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
372 if (prev_rate == rate)
373 return 0;
374
375 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
376 writeable = uac2_control_is_writeable(cs_desc->bmControls, UAC2_CS_CONTROL_SAM_FREQ - 1);
377 if (writeable) {
378 data = cpu_to_le32(rate);
379 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
380 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
381 UAC2_CS_CONTROL_SAM_FREQ << 8,
382 snd_usb_ctrl_intf(chip) | (clock << 8),
383 &data, sizeof(data));
384 if (err < 0) {
385 usb_audio_err(chip,
386 "%d:%d: cannot set freq %d (v2): err %d\n",
387 iface, fmt->altsetting, rate, err);
388 return err;
389 }
390
391 cur_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock);
392 } else {
393 cur_rate = prev_rate;
394 }
395
396 if (cur_rate != rate) {
397 if (!writeable) {
398 usb_audio_warn(chip,
399 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
400 iface, fmt->altsetting, rate, cur_rate);
401 return -ENXIO;
402 }
403 usb_audio_dbg(chip,
404 "current rate %d is different from the runtime rate %d\n",
405 cur_rate, rate);
406 }
407
408 /* Some devices doesn't respond to sample rate changes while the
409 * interface is active. */
410 if (rate != prev_rate) {
411 usb_set_interface(dev, iface, 0);
412 snd_usb_set_interface_quirk(dev);
413 usb_set_interface(dev, iface, fmt->altsetting);
414 snd_usb_set_interface_quirk(dev);
415 }
416
417 return 0;
418}
419
420int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
421 struct usb_host_interface *alts,
422 struct audioformat *fmt, int rate)
423{
424 switch (fmt->protocol) {
425 case UAC_VERSION_1:
426 default:
427 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
428
429 case UAC_VERSION_2:
430 return set_sample_rate_v2(chip, iface, alts, fmt, rate);
431 }
432}
433