cachefiles: fix the race between cachefiles_bury_object() and rmdir(2)
[linux/fpc-iii.git] / sound / usb / clock.c
blobdb5e39d67a90ede6f2e67e537fce85f6fe298bd1
1 /*
2 * Clock domain and sample rate management functions
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.
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.
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
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 #include <linux/usb/audio-v3.h>
28 #include <sound/core.h>
29 #include <sound/info.h>
30 #include <sound/pcm.h>
32 #include "usbaudio.h"
33 #include "card.h"
34 #include "helper.h"
35 #include "clock.h"
36 #include "quirks.h"
38 static void *find_uac_clock_desc(struct usb_host_interface *iface, int id,
39 bool (*validator)(void *, int), u8 type)
41 void *cs = NULL;
43 while ((cs = snd_usb_find_csint_desc(iface->extra, iface->extralen,
44 cs, type))) {
45 if (validator(cs, id))
46 return cs;
49 return NULL;
52 static bool validate_clock_source_v2(void *p, int id)
54 struct uac_clock_source_descriptor *cs = p;
55 return cs->bLength == sizeof(*cs) && cs->bClockID == id;
58 static bool validate_clock_source_v3(void *p, int id)
60 struct uac3_clock_source_descriptor *cs = p;
61 return cs->bLength == sizeof(*cs) && cs->bClockID == id;
64 static bool validate_clock_selector_v2(void *p, int id)
66 struct uac_clock_selector_descriptor *cs = p;
67 return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
68 cs->bLength == 7 + cs->bNrInPins;
71 static bool validate_clock_selector_v3(void *p, int id)
73 struct uac3_clock_selector_descriptor *cs = p;
74 return cs->bLength >= sizeof(*cs) && cs->bClockID == id &&
75 cs->bLength == 11 + cs->bNrInPins;
78 static bool validate_clock_multiplier_v2(void *p, int id)
80 struct uac_clock_multiplier_descriptor *cs = p;
81 return cs->bLength == sizeof(*cs) && cs->bClockID == id;
84 static bool validate_clock_multiplier_v3(void *p, int id)
86 struct uac3_clock_multiplier_descriptor *cs = p;
87 return cs->bLength == sizeof(*cs) && cs->bClockID == id;
90 #define DEFINE_FIND_HELPER(name, obj, validator, type) \
91 static obj *name(struct usb_host_interface *iface, int id) \
92 { \
93 return find_uac_clock_desc(iface, id, validator, type); \
96 DEFINE_FIND_HELPER(snd_usb_find_clock_source,
97 struct uac_clock_source_descriptor,
98 validate_clock_source_v2, UAC2_CLOCK_SOURCE);
99 DEFINE_FIND_HELPER(snd_usb_find_clock_source_v3,
100 struct uac3_clock_source_descriptor,
101 validate_clock_source_v3, UAC3_CLOCK_SOURCE);
103 DEFINE_FIND_HELPER(snd_usb_find_clock_selector,
104 struct uac_clock_selector_descriptor,
105 validate_clock_selector_v2, UAC2_CLOCK_SELECTOR);
106 DEFINE_FIND_HELPER(snd_usb_find_clock_selector_v3,
107 struct uac3_clock_selector_descriptor,
108 validate_clock_selector_v3, UAC3_CLOCK_SELECTOR);
110 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier,
111 struct uac_clock_multiplier_descriptor,
112 validate_clock_multiplier_v2, UAC2_CLOCK_MULTIPLIER);
113 DEFINE_FIND_HELPER(snd_usb_find_clock_multiplier_v3,
114 struct uac3_clock_multiplier_descriptor,
115 validate_clock_multiplier_v3, UAC3_CLOCK_MULTIPLIER);
117 static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_id)
119 unsigned char buf;
120 int ret;
122 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0),
123 UAC2_CS_CUR,
124 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
125 UAC2_CX_CLOCK_SELECTOR << 8,
126 snd_usb_ctrl_intf(chip) | (selector_id << 8),
127 &buf, sizeof(buf));
129 if (ret < 0)
130 return ret;
132 return buf;
135 static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id,
136 unsigned char pin)
138 int ret;
140 ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0),
141 UAC2_CS_CUR,
142 USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
143 UAC2_CX_CLOCK_SELECTOR << 8,
144 snd_usb_ctrl_intf(chip) | (selector_id << 8),
145 &pin, sizeof(pin));
146 if (ret < 0)
147 return ret;
149 if (ret != sizeof(pin)) {
150 usb_audio_err(chip,
151 "setting selector (id %d) unexpected length %d\n",
152 selector_id, ret);
153 return -EINVAL;
156 ret = uac_clock_selector_get_val(chip, selector_id);
157 if (ret < 0)
158 return ret;
160 if (ret != pin) {
161 usb_audio_err(chip,
162 "setting selector (id %d) to %x failed (current: %d)\n",
163 selector_id, pin, ret);
164 return -EINVAL;
167 return ret;
170 static bool uac_clock_source_is_valid(struct snd_usb_audio *chip,
171 int protocol,
172 int source_id)
174 int err;
175 unsigned char data;
176 struct usb_device *dev = chip->dev;
177 u32 bmControls;
179 if (protocol == UAC_VERSION_3) {
180 struct uac3_clock_source_descriptor *cs_desc =
181 snd_usb_find_clock_source_v3(chip->ctrl_intf, source_id);
183 if (!cs_desc)
184 return 0;
185 bmControls = le32_to_cpu(cs_desc->bmControls);
186 } else { /* UAC_VERSION_1/2 */
187 struct uac_clock_source_descriptor *cs_desc =
188 snd_usb_find_clock_source(chip->ctrl_intf, source_id);
190 if (!cs_desc)
191 return 0;
192 bmControls = cs_desc->bmControls;
195 /* If a clock source can't tell us whether it's valid, we assume it is */
196 if (!uac_v2v3_control_is_readable(bmControls,
197 UAC2_CS_CONTROL_CLOCK_VALID))
198 return 1;
200 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
201 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
202 UAC2_CS_CONTROL_CLOCK_VALID << 8,
203 snd_usb_ctrl_intf(chip) | (source_id << 8),
204 &data, sizeof(data));
206 if (err < 0) {
207 dev_warn(&dev->dev,
208 "%s(): cannot get clock validity for id %d\n",
209 __func__, source_id);
210 return 0;
213 return !!data;
216 static int __uac_clock_find_source(struct snd_usb_audio *chip, int entity_id,
217 unsigned long *visited, bool validate)
219 struct uac_clock_source_descriptor *source;
220 struct uac_clock_selector_descriptor *selector;
221 struct uac_clock_multiplier_descriptor *multiplier;
223 entity_id &= 0xff;
225 if (test_and_set_bit(entity_id, visited)) {
226 usb_audio_warn(chip,
227 "%s(): recursive clock topology detected, id %d.\n",
228 __func__, entity_id);
229 return -EINVAL;
232 /* first, see if the ID we're looking for is a clock source already */
233 source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id);
234 if (source) {
235 entity_id = source->bClockID;
236 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_2,
237 entity_id)) {
238 usb_audio_err(chip,
239 "clock source %d is not valid, cannot use\n",
240 entity_id);
241 return -ENXIO;
243 return entity_id;
246 selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id);
247 if (selector) {
248 int ret, i, cur;
250 /* the entity ID we are looking for is a selector.
251 * find out what it currently selects */
252 ret = uac_clock_selector_get_val(chip, selector->bClockID);
253 if (ret < 0)
254 return ret;
256 /* Selector values are one-based */
258 if (ret > selector->bNrInPins || ret < 1) {
259 usb_audio_err(chip,
260 "%s(): selector reported illegal value, id %d, ret %d\n",
261 __func__, selector->bClockID, ret);
263 return -EINVAL;
266 cur = ret;
267 ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1],
268 visited, validate);
269 if (!validate || ret > 0 || !chip->autoclock)
270 return ret;
272 /* The current clock source is invalid, try others. */
273 for (i = 1; i <= selector->bNrInPins; i++) {
274 int err;
276 if (i == cur)
277 continue;
279 ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1],
280 visited, true);
281 if (ret < 0)
282 continue;
284 err = uac_clock_selector_set_val(chip, entity_id, i);
285 if (err < 0)
286 continue;
288 usb_audio_info(chip,
289 "found and selected valid clock source %d\n",
290 ret);
291 return ret;
294 return -ENXIO;
297 /* FIXME: multipliers only act as pass-thru element for now */
298 multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id);
299 if (multiplier)
300 return __uac_clock_find_source(chip, multiplier->bCSourceID,
301 visited, validate);
303 return -EINVAL;
306 static int __uac3_clock_find_source(struct snd_usb_audio *chip, int entity_id,
307 unsigned long *visited, bool validate)
309 struct uac3_clock_source_descriptor *source;
310 struct uac3_clock_selector_descriptor *selector;
311 struct uac3_clock_multiplier_descriptor *multiplier;
313 entity_id &= 0xff;
315 if (test_and_set_bit(entity_id, visited)) {
316 usb_audio_warn(chip,
317 "%s(): recursive clock topology detected, id %d.\n",
318 __func__, entity_id);
319 return -EINVAL;
322 /* first, see if the ID we're looking for is a clock source already */
323 source = snd_usb_find_clock_source_v3(chip->ctrl_intf, entity_id);
324 if (source) {
325 entity_id = source->bClockID;
326 if (validate && !uac_clock_source_is_valid(chip, UAC_VERSION_3,
327 entity_id)) {
328 usb_audio_err(chip,
329 "clock source %d is not valid, cannot use\n",
330 entity_id);
331 return -ENXIO;
333 return entity_id;
336 selector = snd_usb_find_clock_selector_v3(chip->ctrl_intf, entity_id);
337 if (selector) {
338 int ret, i, cur;
340 /* the entity ID we are looking for is a selector.
341 * find out what it currently selects */
342 ret = uac_clock_selector_get_val(chip, selector->bClockID);
343 if (ret < 0)
344 return ret;
346 /* Selector values are one-based */
348 if (ret > selector->bNrInPins || ret < 1) {
349 usb_audio_err(chip,
350 "%s(): selector reported illegal value, id %d, ret %d\n",
351 __func__, selector->bClockID, ret);
353 return -EINVAL;
356 cur = ret;
357 ret = __uac3_clock_find_source(chip, selector->baCSourceID[ret - 1],
358 visited, validate);
359 if (!validate || ret > 0 || !chip->autoclock)
360 return ret;
362 /* The current clock source is invalid, try others. */
363 for (i = 1; i <= selector->bNrInPins; i++) {
364 int err;
366 if (i == cur)
367 continue;
369 ret = __uac3_clock_find_source(chip, selector->baCSourceID[i - 1],
370 visited, true);
371 if (ret < 0)
372 continue;
374 err = uac_clock_selector_set_val(chip, entity_id, i);
375 if (err < 0)
376 continue;
378 usb_audio_info(chip,
379 "found and selected valid clock source %d\n",
380 ret);
381 return ret;
384 return -ENXIO;
387 /* FIXME: multipliers only act as pass-thru element for now */
388 multiplier = snd_usb_find_clock_multiplier_v3(chip->ctrl_intf,
389 entity_id);
390 if (multiplier)
391 return __uac3_clock_find_source(chip, multiplier->bCSourceID,
392 visited, validate);
394 return -EINVAL;
398 * For all kinds of sample rate settings and other device queries,
399 * the clock source (end-leaf) must be used. However, clock selectors,
400 * clock multipliers and sample rate converters may be specified as
401 * clock source input to terminal. This functions walks the clock path
402 * to its end and tries to find the source.
404 * The 'visited' bitfield is used internally to detect recursive loops.
406 * Returns the clock source UnitID (>=0) on success, or an error.
408 int snd_usb_clock_find_source(struct snd_usb_audio *chip, int protocol,
409 int entity_id, bool validate)
411 DECLARE_BITMAP(visited, 256);
412 memset(visited, 0, sizeof(visited));
414 switch (protocol) {
415 case UAC_VERSION_2:
416 return __uac_clock_find_source(chip, entity_id, visited,
417 validate);
418 case UAC_VERSION_3:
419 return __uac3_clock_find_source(chip, entity_id, visited,
420 validate);
421 default:
422 return -EINVAL;
426 static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface,
427 struct usb_host_interface *alts,
428 struct audioformat *fmt, int rate)
430 struct usb_device *dev = chip->dev;
431 unsigned int ep;
432 unsigned char data[3];
433 int err, crate;
435 if (get_iface_desc(alts)->bNumEndpoints < 1)
436 return -EINVAL;
437 ep = get_endpoint(alts, 0)->bEndpointAddress;
439 /* if endpoint doesn't have sampling rate control, bail out */
440 if (!(fmt->attributes & UAC_EP_CS_ATTR_SAMPLE_RATE))
441 return 0;
443 data[0] = rate;
444 data[1] = rate >> 8;
445 data[2] = rate >> 16;
446 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
447 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
448 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
449 data, sizeof(data));
450 if (err < 0) {
451 dev_err(&dev->dev, "%d:%d: cannot set freq %d to ep %#x\n",
452 iface, fmt->altsetting, rate, ep);
453 return err;
456 /* Don't check the sample rate for devices which we know don't
457 * support reading */
458 if (snd_usb_get_sample_rate_quirk(chip))
459 return 0;
460 /* the firmware is likely buggy, don't repeat to fail too many times */
461 if (chip->sample_rate_read_error > 2)
462 return 0;
464 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC_GET_CUR,
465 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_IN,
466 UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep,
467 data, sizeof(data));
468 if (err < 0) {
469 dev_err(&dev->dev, "%d:%d: cannot get freq at ep %#x\n",
470 iface, fmt->altsetting, ep);
471 chip->sample_rate_read_error++;
472 return 0; /* some devices don't support reading */
475 crate = data[0] | (data[1] << 8) | (data[2] << 16);
476 if (crate != rate) {
477 dev_warn(&dev->dev, "current rate %d is different from the runtime rate %d\n", crate, rate);
478 // runtime->rate = crate;
481 return 0;
484 static int get_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
485 int altsetting, int clock)
487 struct usb_device *dev = chip->dev;
488 __le32 data;
489 int err;
491 err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_CUR,
492 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
493 UAC2_CS_CONTROL_SAM_FREQ << 8,
494 snd_usb_ctrl_intf(chip) | (clock << 8),
495 &data, sizeof(data));
496 if (err < 0) {
497 dev_warn(&dev->dev, "%d:%d: cannot get freq (v2/v3): err %d\n",
498 iface, altsetting, err);
499 return 0;
502 return le32_to_cpu(data);
505 static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
506 struct usb_host_interface *alts,
507 struct audioformat *fmt, int rate)
509 struct usb_device *dev = chip->dev;
510 __le32 data;
511 int err, cur_rate, prev_rate;
512 int clock;
513 bool writeable;
514 u32 bmControls;
516 /* First, try to find a valid clock. This may trigger
517 * automatic clock selection if the current clock is not
518 * valid.
520 clock = snd_usb_clock_find_source(chip, fmt->protocol,
521 fmt->clock, true);
522 if (clock < 0) {
523 /* We did not find a valid clock, but that might be
524 * because the current sample rate does not match an
525 * external clock source. Try again without validation
526 * and we will do another validation after setting the
527 * rate.
529 clock = snd_usb_clock_find_source(chip, fmt->protocol,
530 fmt->clock, false);
531 if (clock < 0)
532 return clock;
535 prev_rate = get_sample_rate_v2v3(chip, iface, fmt->altsetting, clock);
536 if (prev_rate == rate)
537 goto validation;
539 if (fmt->protocol == UAC_VERSION_3) {
540 struct uac3_clock_source_descriptor *cs_desc;
542 cs_desc = snd_usb_find_clock_source_v3(chip->ctrl_intf, clock);
543 bmControls = le32_to_cpu(cs_desc->bmControls);
544 } else {
545 struct uac_clock_source_descriptor *cs_desc;
547 cs_desc = snd_usb_find_clock_source(chip->ctrl_intf, clock);
548 bmControls = cs_desc->bmControls;
551 writeable = uac_v2v3_control_is_writeable(bmControls,
552 UAC2_CS_CONTROL_SAM_FREQ);
553 if (writeable) {
554 data = cpu_to_le32(rate);
555 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
556 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
557 UAC2_CS_CONTROL_SAM_FREQ << 8,
558 snd_usb_ctrl_intf(chip) | (clock << 8),
559 &data, sizeof(data));
560 if (err < 0) {
561 usb_audio_err(chip,
562 "%d:%d: cannot set freq %d (v2/v3): err %d\n",
563 iface, fmt->altsetting, rate, err);
564 return err;
567 cur_rate = get_sample_rate_v2v3(chip, iface,
568 fmt->altsetting, clock);
569 } else {
570 cur_rate = prev_rate;
573 if (cur_rate != rate) {
574 if (!writeable) {
575 usb_audio_warn(chip,
576 "%d:%d: freq mismatch (RO clock): req %d, clock runs @%d\n",
577 iface, fmt->altsetting, rate, cur_rate);
578 return -ENXIO;
580 usb_audio_dbg(chip,
581 "current rate %d is different from the runtime rate %d\n",
582 cur_rate, rate);
585 /* Some devices doesn't respond to sample rate changes while the
586 * interface is active. */
587 if (rate != prev_rate) {
588 usb_set_interface(dev, iface, 0);
589 snd_usb_set_interface_quirk(dev);
590 usb_set_interface(dev, iface, fmt->altsetting);
591 snd_usb_set_interface_quirk(dev);
594 validation:
595 /* validate clock after rate change */
596 if (!uac_clock_source_is_valid(chip, fmt->protocol, clock))
597 return -ENXIO;
598 return 0;
601 int snd_usb_init_sample_rate(struct snd_usb_audio *chip, int iface,
602 struct usb_host_interface *alts,
603 struct audioformat *fmt, int rate)
605 switch (fmt->protocol) {
606 case UAC_VERSION_1:
607 default:
608 return set_sample_rate_v1(chip, iface, alts, fmt, rate);
610 case UAC_VERSION_3:
611 if (chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
612 if (rate != UAC3_BADD_SAMPLING_RATE)
613 return -ENXIO;
614 else
615 return 0;
617 /* fall through */
618 case UAC_VERSION_2:
619 return set_sample_rate_v2v3(chip, iface, alts, fmt, rate);