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 union uac23_clock_source_desc {
25 struct uac_clock_source_descriptor v2;
26 struct uac3_clock_source_descriptor v3;
29 union uac23_clock_selector_desc {
30 struct uac_clock_selector_descriptor v2;
31 struct uac3_clock_selector_descriptor v3;
34 union uac23_clock_multiplier_desc {
35 struct uac_clock_multiplier_descriptor v2;
36 struct uac_clock_multiplier_descriptor v3;
39 #define GET_VAL(p, proto, field) \
40 ((proto) == UAC_VERSION_3 ? (p)->v3.field : (p)->v2.field)
42 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
43 bool (*validator)(void *, int, int),
48 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
50 if (validator(cs, id, proto))
57 static bool validate_clock_source(void *p, int id, int proto)
59 union uac23_clock_source_desc *cs = p;
61 return GET_VAL(cs, proto, bClockID) == id;
64 static bool validate_clock_selector(void *p, int id, int proto)
66 union uac23_clock_selector_desc *cs = p;
68 return GET_VAL(cs, proto, bClockID) == id;
71 static bool validate_clock_multiplier(void *p, int id, int proto)
73 union uac23_clock_multiplier_desc *cs = p;
75 return GET_VAL(cs, proto, bClockID) == id;
78 #define DEFINE_FIND_HELPER(name, obj, validator, type2, type3) \
79 static obj *name(struct snd_usb_audio *chip, int id, int proto) \
81 return find_uac_clock_desc(chip->ctrl_intf, id, validator, \
82 proto == UAC_VERSION_3 ? (type3) : (type2), \
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);
96 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
101 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
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),
114 static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
119 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
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),
128 if (ret != sizeof(pin)) {
130 "setting selector (id %d) unexpected length %d\n",
135 ret = uac_clock_selector_get_val(chip, selector_id);
141 "setting selector (id %d) to %x failed (current: %d)\n",
142 selector_id, pin, ret);
149 static bool uac_clock_source_is_valid_quirk(struct snd_usb_audio *chip,
150 const struct audioformat *fmt,
156 struct usb_device *dev = chip->dev;
157 union uac23_clock_source_desc *cs_desc;
159 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
163 if (fmt->protocol == UAC_VERSION_2) {
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.
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)
180 * Sample rate changes takes more than 2 seconds for this device. Clock
181 * validity request returns false during that period.
183 if (chip->usb_id == USB_ID(0x07fd, 0x0004)) {
186 while ((!ret) && (count < 50)) {
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));
198 "%s(): cannot get clock validity for id %d\n",
199 __func__, source_id);
211 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
212 const struct audioformat *fmt,
217 struct usb_device *dev = chip->dev;
219 union uac23_clock_source_desc *cs_desc;
221 cs_desc = snd_usb_find_clock_source(chip, source_id, fmt->protocol);
225 if (fmt->protocol == UAC_VERSION_3)
226 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
228 bmControls = cs_desc->v2.bmControls;
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))
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));
243 "%s(): cannot get clock validity for id %d\n",
244 __func__, source_id);
251 return uac_clock_source_is_valid_quirk(chip, fmt, source_id);
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)
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;
263 int proto = fmt->protocol;
267 if (test_and_set_bit(entity_id, visited)) {
269 "%s(): recursive clock topology detected, id %d.\n",
270 __func__, entity_id);
274 /* first, see if the ID we're looking for is a clock source already */
275 source = snd_usb_find_clock_source(chip, entity_id, proto);
277 entity_id = GET_VAL(source, proto, bClockID);
278 if (validate && !uac_clock_source_is_valid(chip, fmt,
281 "clock source %d is not valid, cannot use\n",
288 selector = snd_usb_find_clock_selector(chip, entity_id, proto);
290 pins = GET_VAL(selector, proto, bNrInPins);
291 clock_id = GET_VAL(selector, proto, bClockID);
292 sources = GET_VAL(selector, proto, baCSourceID);
300 /* the entity ID we are looking for is a selector.
301 * find out what it currently selects */
302 ret = uac_clock_selector_get_val(chip, clock_id);
304 if (!chip->autoclock)
309 /* Selector values are one-based */
311 if (ret > pins || ret < 1) {
313 "%s(): selector reported illegal value, id %d, ret %d\n",
314 __func__, clock_id, ret);
316 if (!chip->autoclock)
323 ret = __uac_clock_find_source(chip, fmt,
327 err = uac_clock_selector_set_val(chip, entity_id, cur);
332 if (!validate || ret > 0 || !chip->autoclock)
336 /* The current clock source is invalid, try others. */
337 for (i = 1; i <= pins; i++) {
341 ret = __uac_clock_find_source(chip, fmt,
347 err = uac_clock_selector_set_val(chip, entity_id, i);
352 "found and selected valid clock source %d\n",
360 /* FIXME: multipliers only act as pass-thru element for now */
361 multiplier = snd_usb_find_clock_multiplier(chip, entity_id, proto);
363 return __uac_clock_find_source(chip, fmt,
364 GET_VAL(multiplier, proto, bCSourceID),
371 * For all kinds of sample rate settings and other device queries,
372 * the clock source (end-leaf) must be used. However, clock selectors,
373 * clock multipliers and sample rate converters may be specified as
374 * clock source input to terminal. This functions walks the clock path
375 * to its end and tries to find the source.
377 * The 'visited' bitfield is used internally to detect recursive loops.
379 * Returns the clock source UnitID (>=0) on success, or an error.
381 int snd_usb_clock_find_source(struct snd_usb_audio *chip,
382 const struct audioformat *fmt, bool validate)
384 DECLARE_BITMAP(visited, 256);
385 memset(visited, 0, sizeof(visited));
387 switch (fmt->protocol) {
390 return __uac_clock_find_source(chip, fmt, fmt->clock, visited,
397 static int set_sample_rate_v1(struct snd_usb_audio *chip,
398 const struct audioformat *fmt, int rate)
400 struct usb_device *dev = chip->dev;
401 unsigned char data[3];
404 /* if endpoint doesn't have sampling rate control, bail out */
405 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
410 data[2] = rate >> 16;
411 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
412 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
413 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
414 fmt->endpoint, data, sizeof(data));
416 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
417 fmt->iface, fmt->altsetting, rate, fmt->endpoint);
421 /* Don't check the sample rate for devices which we know don't
423 if (snd_usb_get_sample_rate_quirk(chip))
425 /* the firmware is likely buggy, don't repeat to fail too many times */
426 if (chip->sample_rate_read_error > 2)
429 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
430 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
431 UAC_EP_CS_ATTR_SAMPLE_RATE << 8,
432 fmt->endpoint, data, sizeof(data));
434 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
435 fmt->iface, fmt->altsetting, fmt->endpoint);
436 chip->sample_rate_read_error++;
437 return 0; /* some devices don't support reading */
440 crate = data[0] | (data[1] << 8) | (data[2] << 16);
442 dev_info(&dev->dev, "failed to read current rate; disabling the check\n");
443 chip->sample_rate_read_error = 3; /* three strikes, see above */
448 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
449 // runtime->rate = crate;
455 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
456 int altsetting, int clock)
458 struct usb_device *dev = chip->dev;
462 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
463 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
464 UAC2_CS_CONTROL_SAM_FREQ << 8,
465 snd_usb_ctrl_intf(chip) | (clock << 8),
466 &data, sizeof(data));
468 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
469 iface, altsetting, err);
473 return le32_to_cpu(data);
477 * Try to set the given sample rate:
479 * Return 0 if the clock source is read-only, the actual rate on success,
480 * or a negative error code.
482 * This function gets called from format.c to validate each sample rate, too.
483 * Hence no message is shown upon error
485 int snd_usb_set_sample_rate_v2v3(struct snd_usb_audio *chip,
486 const struct audioformat *fmt,
493 union uac23_clock_source_desc *cs_desc;
495 cs_desc = snd_usb_find_clock_source(chip, clock, fmt->protocol);
496 if (fmt->protocol == UAC_VERSION_3)
497 bmControls = le32_to_cpu(cs_desc->v3.bmControls);
499 bmControls = cs_desc->v2.bmControls;
501 writeable = uac_v2v3_control_is_writeable(bmControls,
502 UAC2_CS_CONTROL_SAM_FREQ);
506 data = cpu_to_le32(rate);
507 err = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), UAC2_CS_CUR,
508 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
509 UAC2_CS_CONTROL_SAM_FREQ << 8,
510 snd_usb_ctrl_intf(chip) | (clock << 8),
511 &data, sizeof(data));
515 return get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
518 static int set_sample_rate_v2v3(struct snd_usb_audio *chip,
519 const struct audioformat *fmt, int rate)
521 int cur_rate, prev_rate;
524 /* First, try to find a valid clock. This may trigger
525 * automatic clock selection if the current clock is not
528 clock = snd_usb_clock_find_source(chip, fmt, true);
530 /* We did not find a valid clock, but that might be
531 * because the current sample rate does not match an
532 * external clock source. Try again without validation
533 * and we will do another validation after setting the
536 clock = snd_usb_clock_find_source(chip, fmt, false);
538 /* Denon DN-X1600 hardcoded
539 * Sample rate seems to be set on the hardware itself
541 if (chip->usb_id == USB_ID(0x154e, 0x500e))
548 prev_rate = get_sample_rate_v2v3(chip, fmt->iface, fmt->altsetting, clock);
549 if (prev_rate == rate)
552 cur_rate = snd_usb_set_sample_rate_v2v3(chip, fmt, clock, rate);
555 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
556 fmt->iface, fmt->altsetting, rate, cur_rate);
561 cur_rate = prev_rate;
563 if (cur_rate != rate) {
565 "%d:%d: freq mismatch: req %d, clock runs @%d\n",
566 fmt->iface, fmt->altsetting, rate, cur_rate);
567 /* continue processing */
571 /* validate clock after rate change */
572 if (!uac_clock_source_is_valid(chip, fmt, clock))
577 int snd_usb_init_sample_rate(struct snd_usb_audio *chip,
578 const struct audioformat *fmt, int rate)
580 usb_audio_dbg(chip, "%d:%d Set sample rate %d, clock %d\n",
581 fmt->iface, fmt->altsetting, rate, fmt->clock);
583 switch (fmt->protocol) {
586 return set_sample_rate_v1(chip, fmt, rate);
589 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
590 if (rate != UAC3_BADD_SAMPLING_RATE)
597 return set_sample_rate_v2v3(chip, fmt, rate);