1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Clock domain and sample rate management functions
6 #include <linux/bitops.h>
7 #include <linux/init.h>
8 #include <linux/string.h>
10 #include <linux/usb/audio.h>
11 #include <linux/usb/audio-v2.h>
12 #include <linux/usb/audio-v3.h>
14 #include <sound/core.h>
15 #include <sound/info.h>
16 #include <sound/pcm.h>
24 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
25 bool (*validator)(void *, int), u8 type)
29 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
31 if (validator(cs, id))
38 static bool validate_clock_source_v2(void *p, int id)
40 struct uac_clock_source_descriptor *cs = p;
41 return cs->bClockID == id;
44 static bool validate_clock_source_v3(void *p, int id)
46 struct uac3_clock_source_descriptor *cs = p;
47 return cs->bClockID == id;
50 static bool validate_clock_selector_v2(void *p, int id)
52 struct uac_clock_selector_descriptor *cs = p;
53 return cs->bClockID == id;
56 static bool validate_clock_selector_v3(void *p, int id)
58 struct uac3_clock_selector_descriptor *cs = p;
59 return cs->bClockID == id;
62 static bool validate_clock_multiplier_v2(void *p, int id)
64 struct uac_clock_multiplier_descriptor *cs = p;
65 return cs->bClockID == id;
68 static bool validate_clock_multiplier_v3(void *p, int id)
70 struct uac3_clock_multiplier_descriptor *cs = p;
71 return cs->bClockID == id;
74 #define DEFINE_FIND_HELPER(name, obj, validator, type) \
75 static obj *name(struct usb_host_interface *iface, int id) \
77 return find_uac_clock_desc(iface, id, validator, type); \
80 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
81 struct uac_clock_source_descriptor,
82 validate_clock_source_v2, UAC2_CLOCK_SOURCE);
83 DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
84 struct uac3_clock_source_descriptor,
85 validate_clock_source_v3, UAC3_CLOCK_SOURCE);
87 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
88 struct uac_clock_selector_descriptor,
89 validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
90 DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
91 struct uac3_clock_selector_descriptor,
92 validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
94 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
95 struct uac_clock_multiplier_descriptor,
96 validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
97 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
98 struct uac3_clock_multiplier_descriptor,
99 validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
101 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
106 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
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),
119 static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
124 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
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),
133 if (ret != sizeof(pin)) {
135 "setting selector (id %d) unexpected length %d\n",
140 ret = uac_clock_selector_get_val(chip, selector_id);
146 "setting selector (id %d) to %x failed (current: %d)\n",
147 selector_id, pin, ret);
154 static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
155 const struct audioformat *fmt,
161 struct usb_device *dev = chip->dev;
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);
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.
177 if (fmt->nr_rates == 1 &&
178 (fmt->clock & 0xff) == cs_desc->bClockID &&
179 (cs_desc->bmAttributes & 0x3) !=
180 UAC_CLOCK_SOURCE_TYPE_EXT)
186 * Sample rate changes takes more than 2 seconds for this device. Clock
187 * validity request returns false during that period.
189 if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
192 while ((!ret) && (count < 50)) {
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));
204 "%s(): cannot get clock validity for id %d\n",
205 __func__, source_id);
217 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
218 const struct audioformat *fmt,
223 struct usb_device *dev = chip->dev;
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);
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);
239 bmControls = cs_desc->bmControls;
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))
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));
255 "%s(): cannot get clock validity for id %d\n",
256 __func__, source_id);
263 return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
266 static int __uac_clock_find_source(struct snd_usb_audio *chip,
267 const struct audioformat *fmt, int entity_id,
268 unsigned long *visited, bool validate)
270 struct uac_clock_source_descriptor *source;
271 struct uac_clock_selector_descriptor *selector;
272 struct uac_clock_multiplier_descriptor *multiplier;
276 if (test_and_set_bit(entity_id, visited)) {
278 "%s(): recursive clock topology detected, id %d.\n",
279 __func__, entity_id);
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);
286 entity_id = source->bClockID;
287 if (validate && !uac_clock_source_is_valid(chip, fmt,
290 "clock source %d is not valid, cannot use\n",
297 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
301 if (selector->bNrInPins == 1) {
306 /* the entity ID we are looking for is a selector.
307 * find out what it currently selects */
308 ret = uac_clock_selector_get_val(chip, selector->bClockID);
312 /* Selector values are one-based */
314 if (ret > selector->bNrInPins || ret < 1) {
316 "%s(): selector reported illegal value, id %d, ret %d\n",
317 __func__, selector->bClockID, ret);
324 ret = __uac_clock_find_source(chip, fmt,
325 selector->baCSourceID[ret - 1],
327 if (!validate || ret > 0 || !chip->autoclock)
330 /* The current clock source is invalid, try others. */
331 for (i = 1; i <= selector->bNrInPins; i++) {
337 ret = __uac_clock_find_source(chip, fmt,
338 selector->baCSourceID[i - 1],
343 err = uac_clock_selector_set_val(chip, entity_id, i);
348 "found and selected valid clock source %d\n",
356 /* FIXME: multipliers only act as pass-thru element for now */
357 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
359 return __uac_clock_find_source(chip, fmt,
360 multiplier->bCSourceID,
366 static int __uac3_clock_find_source(struct snd_usb_audio *chip,
367 const struct audioformat *fmt, int entity_id,
368 unsigned long *visited, bool validate)
370 struct uac3_clock_source_descriptor *source;
371 struct uac3_clock_selector_descriptor *selector;
372 struct uac3_clock_multiplier_descriptor *multiplier;
376 if (test_and_set_bit(entity_id, visited)) {
378 "%s(): recursive clock topology detected, id %d.\n",
379 __func__, entity_id);
383 /* first, see if the ID we're looking for is a clock source already */
384 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
386 entity_id = source->bClockID;
387 if (validate && !uac_clock_source_is_valid(chip, fmt,
390 "clock source %d is not valid, cannot use\n",
397 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
401 /* the entity ID we are looking for is a selector.
402 * find out what it currently selects */
403 ret = uac_clock_selector_get_val(chip, selector->bClockID);
407 /* Selector values are one-based */
409 if (ret > selector->bNrInPins || ret < 1) {
411 "%s(): selector reported illegal value, id %d, ret %d\n",
412 __func__, selector->bClockID, ret);
418 ret = __uac3_clock_find_source(chip, fmt,
419 selector->baCSourceID[ret - 1],
421 if (!validate || ret > 0 || !chip->autoclock)
424 /* The current clock source is invalid, try others. */
425 for (i = 1; i <= selector->bNrInPins; i++) {
431 ret = __uac3_clock_find_source(chip, fmt,
432 selector->baCSourceID[i - 1],
437 err = uac_clock_selector_set_val(chip, entity_id, i);
442 "found and selected valid clock source %d\n",
450 /* FIXME: multipliers only act as pass-thru element for now */
451 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
454 return __uac3_clock_find_source(chip, fmt,
455 multiplier->bCSourceID,
462 * For all kinds of sample rate settings and other device queries,
463 * the clock source (end-leaf) must be used. However, clock selectors,
464 * clock multipliers and sample rate converters may be specified as
465 * clock source input to terminal. This functions walks the clock path
466 * to its end and tries to find the source.
468 * The 'visited' bitfield is used internally to detect recursive loops.
470 * Returns the clock source UnitID (>=0) on success, or an error.
472 int snd_usb_clock_find_source(struct snd_usb_audio *chip,
473 const struct audioformat *fmt, bool validate)
475 DECLARE_BITMAP(visited, 256);
476 memset(visited, 0, sizeof(visited));
478 switch (fmt->protocol) {
480 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
483 return __uac3_clock_find_source(chip, fmt, fmt->clock, visited,
490 static int set_sample_rate_v1(struct snd_usb_audio *chip,
491 const struct audioformat *fmt, int rate)
493 struct usb_device *dev = chip->dev;
494 unsigned char data[3];
497 /* if endpoint doesn't have sampling rate control, bail out */
498 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
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,
507 fmt->endpoint, data, sizeof(data));
509 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
510 fmt->iface, fmt->altsetting, rate, fmt->endpoint);
514 /* Don't check the sample rate for devices which we know don't
516 if (snd_usb_get_sample_rate_quirk(chip))
518 /* the firmware is likely buggy, don't repeat to fail too many times */
519 if (chip->sample_rate_read_error > 2)
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,
525 fmt->endpoint, data, sizeof(data));
527 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
528 fmt->iface, fmt->altsetting, fmt->endpoint);
529 chip->sample_rate_read_error++;
530 return 0; /* some devices don't support reading */
533 crate = data[0] | (data[1] << 8) | (data[2] << 16);
535 dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
536 chip->sample_rate_read_error = 3; /* three strikes, see above */
541 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
542 // runtime->rate = crate;
548 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
549 int altsetting, int clock)
551 struct usb_device *dev = chip->dev;
555 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
556 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
557 UAC2_CS_CONTROL_SAM_FREQ << 8,
558 snd_usb_ctrl_intf(chip) | (clock << 8),
559 &data, sizeof(data));
561 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
562 iface, altsetting, err);
566 return le32_to_cpu(data);
570 * Try to set the given sample rate:
572 * Return 0 if the clock source is read-only, the actual rate on success,
573 * or a negative error code.
575 * This function gets called from format.c to validate each sample rate, too.
576 * Hence no message is shown upon error
578 int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
579 const struct audioformat *fmt,
587 if (fmt->protocol == UAC_VERSION_3) {
588 struct uac3_clock_source_descriptor *cs_desc;
590 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
591 bmControls = le32_to_cpu(cs_desc->bmControls);
593 struct uac_clock_source_descriptor *cs_desc;
595 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
596 bmControls = cs_desc->bmControls;
599 writeable = uac_v2v3_control_is_writeable(bmControls,
600 UAC2_CS_CONTROL_SAM_FREQ);
604 data = cpu_to_le32(rate);
605 err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
606 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
607 UAC2_CS_CONTROL_SAM_FREQ << 8,
608 snd_usb_ctrl_intf(chip) | (clock << 8),
609 &data, sizeof(data));
613 return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
616 static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
617 const struct audioformat *fmt, int rate)
619 int cur_rate, prev_rate;
622 /* First, try to find a valid clock. This may trigger
623 * automatic clock selection if the current clock is not
626 clock = snd_usb_clock_find_source(chip, fmt, true);
628 /* We did not find a valid clock, but that might be
629 * because the current sample rate does not match an
630 * external clock source. Try again without validation
631 * and we will do another validation after setting the
634 clock = snd_usb_clock_find_source(chip, fmt, false);
639 prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
640 if (prev_rate == rate)
643 cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
646 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
647 fmt->iface, fmt->altsetting, rate, cur_rate);
652 cur_rate = prev_rate;
654 if (cur_rate != rate) {
656 "%d:%d: freq mismatch: req %d, clock runs @%d\n",
657 fmt->iface, fmt->altsetting, rate, cur_rate);
658 /* continue processing */
662 /* validate clock after rate change */
663 if (!uac_clock_source_is_valid(chip, fmt, clock))
668 int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
669 const struct audioformat *fmt, int rate)
671 usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
672 fmt->iface, fmt->altsetting, rate, fmt->clock);
674 switch (fmt->protocol) {
677 return set_sample_rate_v1(chip, fmt, rate);
680 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
681 if (rate != UAC3_BADD_SAMPLING_RATE)
688 return set_sample_rate_v2v3(chip, fmt, rate);