1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Clock domain and sample rate management functions
4 */
5
6 #include <linux/bitops.h>
7 #include <linux/init.h>
8 #include <linux/string.h>
9 #include <linux/usb.h>
10 #include <linux/usb/audio.h>
11 #include <linux/usb/audio-v2.h>
12 #include <linux/usb/audio-v3.h>
13
14 #include <sound/core.h>
15 #include <sound/info.h>
16 #include <sound/pcm.h>
17
18 #include "usbaudio.h"
19 #include "card.h"
20 #include "helper.h"
21 #include "clock.h"
22 #include "quirks.h"
23
24 union uac23_clock_source_desc {
25 struct uac_clock_source_descriptor v2;
26 struct uac3_clock_source_descriptor v3;
27 };
28
29 union uac23_clock_selector_desc {
30 struct uac_clock_selector_descriptor v2;
31 struct uac3_clock_selector_descriptor v3;
32 };
33
34 union 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
find_uac_clock_desc(struct usb_host_interface * iface,int id,bool (* validator)(void *,int,int),u8 type,int proto)42 static 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
validate_clock_source(void * p,int id,int proto)57 static 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
validate_clock_selector(void * p,int id,int proto)64 static 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
validate_clock_multiplier(void * p,int id,int proto)71 static 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) \
79 static 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
86 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
87 union uac23_clock_source_desc, validate_clock_source,
88 UAC2_CLOCK_SOURCE, UAC3_CLOCK_SOURCE);
89 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
90 union uac23_clock_selector_desc, validate_clock_selector,
91 UAC2_CLOCK_SELECTOR, UAC3_CLOCK_SELECTOR);
92 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
93 union uac23_clock_multiplier_desc, validate_clock_multiplier,
94 UAC2_CLOCK_MULTIPLIER, UAC3_CLOCK_MULTIPLIER);
95
uac_clock_selector_get_val(struct snd_usb_audio * chip,int selector_id)96 static 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
uac_clock_selector_set_val(struct snd_usb_audio * chip,int selector_id,unsigned char pin)114 static 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
uac_clock_source_is_valid_quirk(struct snd_usb_audio * chip,const struct audioformat * fmt,int source_id)149 static 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
uac_clock_source_is_valid(struct snd_usb_audio * chip,const struct audioformat * fmt,int source_id)211 static 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
__uac_clock_find_source(struct snd_usb_audio * chip,const struct audioformat * fmt,int entity_id,unsigned long * visited,bool validate)254 static 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 if (pins == 1) {
333 usb_audio_dbg(chip,
334 "%s(): selector returned an error, "
335 "assuming a firmware bug, id %d, ret %d\n",
336 __func__, clock_id, err);
337 return ret;
338 }
339 return err;
340 }
341 }
342
343 if (!validate || ret > 0 || !chip->autoclock)
344 return ret;
345
346 find_others:
347 /* The current clock source is invalid, try others. */
348 for (i = 1; i <= pins; i++) {
349 if (i == cur)
350 continue;
351
352 ret = __uac_clock_find_source(chip, fmt,
353 sources[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(chip, entity_id, proto);
373 if (multiplier)
374 return __uac_clock_find_source(chip, fmt,
375 GET_VAL(multiplier, proto, 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 */
snd_usb_clock_find_source(struct snd_usb_audio * chip,const struct audioformat * fmt,bool validate)392 int snd_usb_clock_find_source(struct snd_usb_audio *chip,
393 const struct audioformat *fmt, bool validate)
394 {
395 DECLARE_BITMAP(visited, 256);
396 memset(visited, 0, sizeof(visited));
397
398 switch (fmt->protocol) {
399 case UAC_VERSION_2:
400 case UAC_VERSION_3:
401 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
402 validate);
403 default:
404 return -EINVAL;
405 }
406 }
407
set_sample_rate_v1(struct snd_usb_audio * chip,const struct audioformat * fmt,int rate)408 static int set_sample_rate_v1(struct snd_usb_audio *chip,
409 const struct audioformat *fmt, int rate)
410 {
411 struct usb_device *dev = chip->dev;
412 unsigned char data[3];
413 int err, crate;
414
415 /* if endpoint doesn't have sampling rate control, bail out */
416 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
417 return 0;
418
419 data[0] = rate;
420 data[1] = rate >> 8;
421 data[2] = rate >> 16;
422 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
423 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
424 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
425 fmt->endpoint, data, sizeof(data));
426 if (err < 0) {
427 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
428 fmt->iface, fmt->altsetting, rate, fmt->endpoint);
429 return err;
430 }
431
432 /* Don't check the sample rate for devices which we know don't
433 * support reading */
434 if (chip->quirk_flags & QUIRK_FLAG_GET_SAMPLE_RATE)
435 return 0;
436 /* the firmware is likely buggy, don't repeat to fail too many times */
437 if (chip->sample_rate_read_error > 2)
438 return 0;
439
440 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
441 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
442 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
443 fmt->endpoint, data, sizeof(data));
444 if (err < 0) {
445 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
446 fmt->iface, fmt->altsetting, fmt->endpoint);
447 chip->sample_rate_read_error++;
448 return 0; /* some devices don't support reading */
449 }
450
451 crate = data[0] | (data[1] << 8) | (data[2] << 16);
452 if (!crate) {
453 dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
454 chip->sample_rate_read_error = 3; /* three strikes, see above */
455 return 0;
456 }
457
458 if (crate != rate) {
459 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
460 // runtime->rate = crate;
461 }
462
463 return 0;
464 }
465
get_sample_rate_v2v3(struct snd_usb_audio * chip,int iface,int altsetting,int clock)466 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
467 int altsetting, int clock)
468 {
469 struct usb_device *dev = chip->dev;
470 __le32 data;
471 int err;
472
473 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
474 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
475 UAC2_CS_CONTROL_SAM_FREQ << 8,
476 snd_usb_ctrl_intf(chip) | (clock << 8),
477 &data, sizeof(data));
478 if (err < 0) {
479 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
480 iface, altsetting, err);
481 return 0;
482 }
483
484 return le32_to_cpu(data);
485 }
486
487 /*
488 * Try to set the given sample rate:
489 *
490 * Return 0 if the clock source is read-only, the actual rate on success,
491 * or a negative error code.
492 *
493 * This function gets called from format.c to validate each sample rate, too.
494 * Hence no message is shown upon error
495 */
snd_usb_set_sample_rate_v2v3(struct snd_usb_audio * chip,const struct audioformat * fmt,int clock,int rate)496 int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
497 const struct audioformat *fmt,
498 int clock, int rate)
499 {
500 bool writeable;
501 u32 bmControls;
502 __le32 data;
503 int err;
504 union uac23_clock_source_desc *cs_desc;
505
506 cs_desc = snd_usb_find_clock_source(chip, clock, fmt->protocol);
507
508 if (!cs_desc)
509 return 0;
510
511 if (fmt->protocol == UAC_VERSION_3)
512 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
513 else
514 bmControls = cs_desc->v2.bmControls;
515
516 writeable = uac_v2v3_control_is_writeable(bmControls,
517 UAC2_CS_CONTROL_SAM_FREQ);
518 if (!writeable)
519 return 0;
520
521 data = cpu_to_le32(rate);
522 err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
523 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
524 UAC2_CS_CONTROL_SAM_FREQ << 8,
525 snd_usb_ctrl_intf(chip) | (clock << 8),
526 &data, sizeof(data));
527 if (err < 0)
528 return err;
529
530 return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
531 }
532
set_sample_rate_v2v3(struct snd_usb_audio * chip,const struct audioformat * fmt,int rate)533 static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
534 const struct audioformat *fmt, int rate)
535 {
536 int cur_rate, prev_rate;
537 int clock;
538
539 /* First, try to find a valid clock. This may trigger
540 * automatic clock selection if the current clock is not
541 * valid.
542 */
543 clock = snd_usb_clock_find_source(chip, fmt, true);
544 if (clock < 0) {
545 /* We did not find a valid clock, but that might be
546 * because the current sample rate does not match an
547 * external clock source. Try again without validation
548 * and we will do another validation after setting the
549 * rate.
550 */
551 clock = snd_usb_clock_find_source(chip, fmt, false);
552
553 /* Hardcoded sample rates */
554 if (chip->quirk_flags & QUIRK_FLAG_IGNORE_CLOCK_SOURCE)
555 return 0;
556
557 if (clock < 0)
558 return clock;
559 }
560
561 prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
562 if (prev_rate == rate)
563 goto validation;
564
565 cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
566 if (cur_rate < 0) {
567 usb_audio_err(chip,
568 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
569 fmt->iface, fmt->altsetting, rate, cur_rate);
570 return cur_rate;
571 }
572
573 if (!cur_rate)
574 cur_rate = prev_rate;
575
576 if (cur_rate != rate) {
577 usb_audio_dbg(chip,
578 "%d:%d: freq mismatch: req %d, clock runs @%d\n",
579 fmt->iface, fmt->altsetting, rate, cur_rate);
580 /* continue processing */
581 }
582
583 /* FIXME - TEAC devices require the immediate interface setup */
584 if (USB_ID_VENDOR(chip->usb_id) == 0x0644) {
585 bool cur_base_48k = (rate % 48000 == 0);
586 bool prev_base_48k = (prev_rate % 48000 == 0);
587 if (cur_base_48k != prev_base_48k) {
588 usb_set_interface(chip->dev, fmt->iface, fmt->altsetting);
589 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
590 msleep(50);
591 }
592 }
593
594 validation:
595 /* validate clock after rate change */
596 if (!uac_clock_source_is_valid(chip, fmt, clock))
597 return -ENXIO;
598 return 0;
599 }
600
snd_usb_init_sample_rate(struct snd_usb_audio * chip,const struct audioformat * fmt,int rate)601 int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
602 const struct audioformat *fmt, int rate)
603 {
604 usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
605 fmt->iface, fmt->altsetting, rate, fmt->clock);
606
607 switch (fmt->protocol) {
608 case UAC_VERSION_1:
609 default:
610 return set_sample_rate_v1(chip, fmt, rate);
611
612 case UAC_VERSION_3:
613 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
614 if (rate != UAC3_BADD_SAMPLING_RATE)
615 return -ENXIO;
616 else
617 return 0;
618 }
619 fallthrough;
620 case UAC_VERSION_2:
621 return set_sample_rate_v2v3(chip, fmt, rate);
622 }
623 }
624
625