1 // SPDX-License-Identifier: GPL-2.0-or-later
5 #include <linux/init.h>
6 #include <linux/slab.h>
7 #include <linux/bitrev.h>
8 #include <linux/ratelimit.h>
10 #include <linux/usb/audio.h>
11 #include <linux/usb/audio-v2.h>
13 #include <sound/core.h>
14 #include <sound/pcm.h>
15 #include <sound/pcm_params.h>
28 #define SUBSTREAM_FLAG_DATA_EP_STARTED 0
29 #define SUBSTREAM_FLAG_SYNC_EP_STARTED 1
31 /* return the estimated delay based on USB frame counters */
32 snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,
35 int current_frame_number;
39 if (!subs->last_delay)
40 return 0; /* short path */
42 current_frame_number = usb_get_current_frame_number(subs->dev);
44 * HCD implementations use different widths, use lower 8 bits.
45 * The delay will be managed up to 256ms, which is more than
48 frame_diff = (current_frame_number - subs->last_frame_number) & 0xff;
50 /* Approximation based on number of samples per USB frame (ms),
51 some truncation for 44.1 but the estimate is good enough */
52 est_delay = frame_diff * rate / 1000;
53 if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
54 est_delay = subs->last_delay - est_delay;
56 est_delay = subs->last_delay + est_delay;
64 * return the current pcm pointer. just based on the hwptr_done value.
66 static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream)
68 struct snd_usb_substream *subs = substream->runtime->private_data;
69 unsigned int hwptr_done;
71 if (atomic_read(&subs->stream->chip->shutdown))
72 return SNDRV_PCM_POS_XRUN;
73 spin_lock(&subs->lock);
74 hwptr_done = subs->hwptr_done;
75 substream->runtime->delay = snd_usb_pcm_delay(subs,
76 substream->runtime->rate);
77 spin_unlock(&subs->lock);
78 return hwptr_done / (substream->runtime->frame_bits >> 3);
82 * find a matching audio format
84 static const struct audioformat *
85 find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,
86 unsigned int rate, unsigned int channels, bool strict_match,
87 struct snd_usb_substream *subs)
89 const struct audioformat *fp;
90 const struct audioformat *found = NULL;
91 int cur_attr = 0, attr;
93 list_for_each_entry(fp, fmt_list_head, list) {
95 if (!(fp->formats & pcm_format_to_bits(format)))
97 if (fp->channels != channels)
100 if (rate < fp->rate_min || rate > fp->rate_max)
102 if (!(fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
104 for (i = 0; i < fp->nr_rates; i++)
105 if (fp->rate_table[i] == rate)
107 if (i >= fp->nr_rates)
110 attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
116 /* avoid async out and adaptive in if the other method
117 * supports the same format.
118 * this is a workaround for the case like
119 * M-audio audiophile USB.
121 if (subs && attr != cur_attr) {
122 if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
123 subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
124 (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
125 subs->direction == SNDRV_PCM_STREAM_CAPTURE))
127 if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
128 subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
129 (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
130 subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
136 /* find the format with the largest max. packet size */
137 if (fp->maxpacksize > found->maxpacksize) {
145 static const struct audioformat *
146 find_substream_format(struct snd_usb_substream *subs,
147 const struct snd_pcm_hw_params *params)
149 return find_format(&subs->fmt_list, params_format(params),
150 params_rate(params), params_channels(params),
154 static int init_pitch_v1(struct snd_usb_audio *chip, int ep)
156 struct usb_device *dev = chip->dev;
157 unsigned char data[1];
161 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
162 USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
163 UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
168 static int init_pitch_v2(struct snd_usb_audio *chip, int ep)
170 struct usb_device *dev = chip->dev;
171 unsigned char data[1];
175 err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
176 USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
177 UAC2_EP_CS_PITCH << 8, 0,
183 * initialize the pitch control and sample rate
185 int snd_usb_init_pitch(struct snd_usb_audio *chip,
186 const struct audioformat *fmt)
190 /* if endpoint doesn't have pitch control, bail out */
191 if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
194 usb_audio_dbg(chip, "enable PITCH for EP 0x%x\n", fmt->endpoint);
196 switch (fmt->protocol) {
198 err = init_pitch_v1(chip, fmt->endpoint);
201 err = init_pitch_v2(chip, fmt->endpoint);
208 usb_audio_err(chip, "failed to enable PITCH for EP 0x%x\n",
216 static bool stop_endpoints(struct snd_usb_substream *subs)
220 if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
221 snd_usb_endpoint_stop(subs->sync_endpoint);
224 if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
225 snd_usb_endpoint_stop(subs->data_endpoint);
231 static int start_endpoints(struct snd_usb_substream *subs)
235 if (!subs->data_endpoint)
238 if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
239 err = snd_usb_endpoint_start(subs->data_endpoint);
241 clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
246 if (subs->sync_endpoint &&
247 !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
248 err = snd_usb_endpoint_start(subs->sync_endpoint);
250 clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
258 stop_endpoints(subs);
262 static void sync_pending_stops(struct snd_usb_substream *subs)
264 snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
265 snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
268 /* PCM sync_stop callback */
269 static int snd_usb_pcm_sync_stop(struct snd_pcm_substream *substream)
271 struct snd_usb_substream *subs = substream->runtime->private_data;
273 sync_pending_stops(subs);
277 /* Set up sync endpoint */
278 int snd_usb_audioformat_set_sync_ep(struct snd_usb_audio *chip,
279 struct audioformat *fmt)
281 struct usb_device *dev = chip->dev;
282 struct usb_host_interface *alts;
283 struct usb_interface_descriptor *altsd;
284 unsigned int ep, attr, sync_attr;
288 alts = snd_usb_get_host_interface(chip, fmt->iface, fmt->altsetting);
291 altsd = get_iface_desc(alts);
293 err = snd_usb_parse_implicit_fb_quirk(chip, fmt, alts);
295 return 0; /* matched */
298 * Generic sync EP handling
301 if (altsd->bNumEndpoints < 2)
304 is_playback = !(get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
305 attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
306 if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
307 attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
308 (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
311 sync_attr = get_endpoint(alts, 1)->bmAttributes;
314 * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
315 * if we don't find a sync endpoint, as on M-Audio Transit. In case of
316 * error fall back to SYNC mode and don't create sync endpoint
319 /* check sync-pipe endpoint */
320 /* ... and check descriptor size before accessing bSynchAddress
321 because there is a version of the SB Audigy 2 NX firmware lacking
322 the audio fields in the endpoint descriptors */
323 if ((sync_attr & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
324 (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
325 get_endpoint(alts, 1)->bSynchAddress != 0)) {
327 "%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
328 fmt->iface, fmt->altsetting,
329 get_endpoint(alts, 1)->bmAttributes,
330 get_endpoint(alts, 1)->bLength,
331 get_endpoint(alts, 1)->bSynchAddress);
332 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
336 ep = get_endpoint(alts, 1)->bEndpointAddress;
337 if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
338 get_endpoint(alts, 0)->bSynchAddress != 0 &&
339 ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
340 (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
342 "%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
343 fmt->iface, fmt->altsetting,
344 is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
345 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
351 fmt->sync_iface = altsd->bInterfaceNumber;
352 fmt->sync_altsetting = altsd->bAlternateSetting;
353 fmt->sync_ep_idx = 1;
354 if ((sync_attr & USB_ENDPOINT_USAGE_MASK) == USB_ENDPOINT_USAGE_IMPLICIT_FB)
355 fmt->implicit_fb = 1;
357 dev_dbg(&dev->dev, "%d:%d: found sync_ep=0x%x, iface=%d, alt=%d, implicit_fb=%d\n",
358 fmt->iface, fmt->altsetting, fmt->sync_ep, fmt->sync_iface,
359 fmt->sync_altsetting, fmt->implicit_fb);
364 static int snd_usb_pcm_change_state(struct snd_usb_substream *subs, int state)
371 ret = snd_usb_power_domain_set(subs->stream->chip, subs->str_pd, state);
373 dev_err(&subs->dev->dev,
374 "Cannot change Power Domain ID: %d to state: %d. Err: %d\n",
375 subs->str_pd->pd_id, state, ret);
382 int snd_usb_pcm_suspend(struct snd_usb_stream *as)
386 ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D2);
390 ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D2);
397 int snd_usb_pcm_resume(struct snd_usb_stream *as)
401 ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D1);
405 ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D1);
412 static void close_endpoints(struct snd_usb_audio *chip,
413 struct snd_usb_substream *subs)
415 if (subs->data_endpoint) {
416 snd_usb_endpoint_set_sync(chip, subs->data_endpoint, NULL);
417 snd_usb_endpoint_close(chip, subs->data_endpoint);
418 subs->data_endpoint = NULL;
421 if (subs->sync_endpoint) {
422 snd_usb_endpoint_close(chip, subs->sync_endpoint);
423 subs->sync_endpoint = NULL;
427 static int configure_endpoints(struct snd_usb_audio *chip,
428 struct snd_usb_substream *subs)
432 if (subs->data_endpoint->need_setup) {
433 /* stop any running stream beforehand */
434 if (stop_endpoints(subs))
435 sync_pending_stops(subs);
436 err = snd_usb_endpoint_configure(chip, subs->data_endpoint);
439 snd_usb_set_format_quirk(subs, subs->cur_audiofmt);
442 if (subs->sync_endpoint) {
443 err = snd_usb_endpoint_configure(chip, subs->sync_endpoint);
454 * allocate a buffer and set the given audio format.
456 * so far we use a physically linear buffer although packetize transfer
457 * doesn't need a continuous area.
458 * if sg buffer is supported on the later version of alsa, we'll follow
461 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
462 struct snd_pcm_hw_params *hw_params)
464 struct snd_usb_substream *subs = substream->runtime->private_data;
465 struct snd_usb_audio *chip = subs->stream->chip;
466 const struct audioformat *fmt;
467 const struct audioformat *sync_fmt;
470 ret = snd_media_start_pipeline(subs);
474 fmt = find_substream_format(subs, hw_params);
477 "cannot find format: format=%s, rate=%d, channels=%d\n",
478 snd_pcm_format_name(params_format(hw_params)),
479 params_rate(hw_params), params_channels(hw_params));
484 if (fmt->implicit_fb) {
485 sync_fmt = snd_usb_find_implicit_fb_sync_format(chip, fmt,
490 "cannot find sync format: ep=0x%x, iface=%d:%d, format=%s, rate=%d, channels=%d\n",
491 fmt->sync_ep, fmt->sync_iface,
492 fmt->sync_altsetting,
493 snd_pcm_format_name(params_format(hw_params)),
494 params_rate(hw_params), params_channels(hw_params));
502 ret = snd_usb_lock_shutdown(chip);
506 ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
510 if (subs->data_endpoint) {
511 if (snd_usb_endpoint_compatible(chip, subs->data_endpoint,
514 close_endpoints(chip, subs);
517 subs->data_endpoint = snd_usb_endpoint_open(chip, fmt, hw_params, false);
518 if (!subs->data_endpoint) {
524 subs->sync_endpoint = snd_usb_endpoint_open(chip, sync_fmt,
527 if (!subs->sync_endpoint) {
532 snd_usb_endpoint_set_sync(chip, subs->data_endpoint,
533 subs->sync_endpoint);
536 mutex_lock(&chip->mutex);
537 subs->cur_audiofmt = fmt;
538 mutex_unlock(&chip->mutex);
540 ret = configure_endpoints(chip, subs);
544 close_endpoints(chip, subs);
546 snd_usb_unlock_shutdown(chip);
549 snd_media_stop_pipeline(subs);
557 * reset the audio format and release the buffer
559 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
561 struct snd_usb_substream *subs = substream->runtime->private_data;
562 struct snd_usb_audio *chip = subs->stream->chip;
564 snd_media_stop_pipeline(subs);
565 mutex_lock(&chip->mutex);
566 subs->cur_audiofmt = NULL;
567 mutex_unlock(&chip->mutex);
568 if (!snd_usb_lock_shutdown(chip)) {
569 if (stop_endpoints(subs))
570 sync_pending_stops(subs);
571 close_endpoints(chip, subs);
572 snd_usb_unlock_shutdown(chip);
581 * only a few subtle things...
583 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
585 struct snd_pcm_runtime *runtime = substream->runtime;
586 struct snd_usb_substream *subs = runtime->private_data;
587 struct snd_usb_audio *chip = subs->stream->chip;
590 ret = snd_usb_lock_shutdown(chip);
593 if (snd_BUG_ON(!subs->data_endpoint)) {
598 ret = configure_endpoints(chip, subs);
602 /* reset the pointer */
603 subs->hwptr_done = 0;
604 subs->transfer_done = 0;
605 subs->last_delay = 0;
606 subs->last_frame_number = 0;
609 /* for playback, submit the URBs now; otherwise, the first hwptr_done
610 * updates for all URBs would happen at the same time when starting */
611 if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
612 ret = start_endpoints(subs);
615 snd_usb_unlock_shutdown(chip);
623 #ifdef HW_CONST_DEBUG
624 #define hwc_debug(fmt, args...) pr_debug(fmt, ##args)
626 #define hwc_debug(fmt, args...) do { } while(0)
629 static const struct snd_pcm_hardware snd_usb_hardware =
631 .info = SNDRV_PCM_INFO_MMAP |
632 SNDRV_PCM_INFO_MMAP_VALID |
633 SNDRV_PCM_INFO_BATCH |
634 SNDRV_PCM_INFO_INTERLEAVED |
635 SNDRV_PCM_INFO_BLOCK_TRANSFER |
636 SNDRV_PCM_INFO_PAUSE,
639 .buffer_bytes_max = 1024 * 1024,
640 .period_bytes_min = 64,
641 .period_bytes_max = 512 * 1024,
646 static int hw_check_valid_format(struct snd_usb_substream *subs,
647 struct snd_pcm_hw_params *params,
648 const struct audioformat *fp)
650 struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
651 struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
652 struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
653 struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
654 struct snd_mask check_fmts;
657 /* check the format */
658 snd_mask_none(&check_fmts);
659 check_fmts.bits[0] = (u32)fp->formats;
660 check_fmts.bits[1] = (u32)(fp->formats >> 32);
661 snd_mask_intersect(&check_fmts, fmts);
662 if (snd_mask_empty(&check_fmts)) {
663 hwc_debug(" > check: no supported format 0x%llx\n", fp->formats);
666 /* check the channels */
667 if (fp->channels < ct->min || fp->channels > ct->max) {
668 hwc_debug(" > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
671 /* check the rate is within the range */
672 if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
673 hwc_debug(" > check: rate_min %d > max %d\n", fp->rate_min, it->max);
676 if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
677 hwc_debug(" > check: rate_max %d < min %d\n", fp->rate_max, it->min);
680 /* check whether the period time is >= the data packet interval */
681 if (subs->speed != USB_SPEED_FULL) {
682 ptime = 125 * (1 << fp->datainterval);
683 if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
684 hwc_debug(" > check: ptime %u > max %u\n", ptime, pt->max);
691 static int apply_hw_params_minmax(struct snd_interval *it, unsigned int rmin,
697 hwc_debug(" --> get empty\n");
703 if (it->min < rmin) {
708 if (it->max > rmax) {
713 if (snd_interval_checkempty(it)) {
717 hwc_debug(" --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
721 static int hw_rule_rate(struct snd_pcm_hw_params *params,
722 struct snd_pcm_hw_rule *rule)
724 struct snd_usb_substream *subs = rule->private;
725 const struct audioformat *fp;
726 struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
727 unsigned int rmin, rmax, r;
730 hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
733 list_for_each_entry(fp, &subs->fmt_list, list) {
734 if (!hw_check_valid_format(subs, params, fp))
736 if (fp->rate_table && fp->nr_rates) {
737 for (i = 0; i < fp->nr_rates; i++) {
738 r = fp->rate_table[i];
739 if (!snd_interval_test(it, r))
745 rmin = min(rmin, fp->rate_min);
746 rmax = max(rmax, fp->rate_max);
750 return apply_hw_params_minmax(it, rmin, rmax);
754 static int hw_rule_channels(struct snd_pcm_hw_params *params,
755 struct snd_pcm_hw_rule *rule)
757 struct snd_usb_substream *subs = rule->private;
758 const struct audioformat *fp;
759 struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
760 unsigned int rmin, rmax;
762 hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
765 list_for_each_entry(fp, &subs->fmt_list, list) {
766 if (!hw_check_valid_format(subs, params, fp))
768 rmin = min(rmin, fp->channels);
769 rmax = max(rmax, fp->channels);
772 return apply_hw_params_minmax(it, rmin, rmax);
775 static int apply_hw_params_format_bits(struct snd_mask *fmt, u64 fbits)
780 oldbits[0] = fmt->bits[0];
781 oldbits[1] = fmt->bits[1];
782 fmt->bits[0] &= (u32)fbits;
783 fmt->bits[1] &= (u32)(fbits >> 32);
784 if (!fmt->bits[0] && !fmt->bits[1]) {
785 hwc_debug(" --> get empty\n");
788 changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
789 hwc_debug(" --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
793 static int hw_rule_format(struct snd_pcm_hw_params *params,
794 struct snd_pcm_hw_rule *rule)
796 struct snd_usb_substream *subs = rule->private;
797 const struct audioformat *fp;
798 struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
801 hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
803 list_for_each_entry(fp, &subs->fmt_list, list) {
804 if (!hw_check_valid_format(subs, params, fp))
806 fbits |= fp->formats;
808 return apply_hw_params_format_bits(fmt, fbits);
811 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
812 struct snd_pcm_hw_rule *rule)
814 struct snd_usb_substream *subs = rule->private;
815 const struct audioformat *fp;
816 struct snd_interval *it;
817 unsigned char min_datainterval;
820 it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
821 hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
822 min_datainterval = 0xff;
823 list_for_each_entry(fp, &subs->fmt_list, list) {
824 if (!hw_check_valid_format(subs, params, fp))
826 min_datainterval = min(min_datainterval, fp->datainterval);
828 if (min_datainterval == 0xff) {
829 hwc_debug(" --> get empty\n");
833 pmin = 125 * (1 << min_datainterval);
835 return apply_hw_params_minmax(it, pmin, UINT_MAX);
838 /* get the EP or the sync EP for implicit fb when it's already set up */
839 static const struct snd_usb_endpoint *
840 get_sync_ep_from_substream(struct snd_usb_substream *subs)
842 struct snd_usb_audio *chip = subs->stream->chip;
843 const struct audioformat *fp;
844 const struct snd_usb_endpoint *ep;
846 list_for_each_entry(fp, &subs->fmt_list, list) {
847 ep = snd_usb_get_endpoint(chip, fp->endpoint);
848 if (ep && ep->cur_audiofmt) {
849 /* if EP is already opened solely for this substream,
850 * we still allow us to change the parameter; otherwise
851 * this substream has to follow the existing parameter
853 if (ep->cur_audiofmt != subs->cur_audiofmt || ep->opened > 1)
856 if (!fp->implicit_fb)
858 /* for the implicit fb, check the sync ep as well */
859 ep = snd_usb_get_endpoint(chip, fp->sync_ep);
860 if (ep && ep->cur_audiofmt)
866 /* additional hw constraints for implicit feedback mode */
867 static int hw_rule_format_implicit_fb(struct snd_pcm_hw_params *params,
868 struct snd_pcm_hw_rule *rule)
870 struct snd_usb_substream *subs = rule->private;
871 const struct snd_usb_endpoint *ep;
872 struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
874 ep = get_sync_ep_from_substream(subs);
878 hwc_debug("applying %s\n", __func__);
879 return apply_hw_params_format_bits(fmt, pcm_format_to_bits(ep->cur_format));
882 static int hw_rule_rate_implicit_fb(struct snd_pcm_hw_params *params,
883 struct snd_pcm_hw_rule *rule)
885 struct snd_usb_substream *subs = rule->private;
886 const struct snd_usb_endpoint *ep;
887 struct snd_interval *it;
889 ep = get_sync_ep_from_substream(subs);
893 hwc_debug("applying %s\n", __func__);
894 it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
895 return apply_hw_params_minmax(it, ep->cur_rate, ep->cur_rate);
898 static int hw_rule_period_size_implicit_fb(struct snd_pcm_hw_params *params,
899 struct snd_pcm_hw_rule *rule)
901 struct snd_usb_substream *subs = rule->private;
902 const struct snd_usb_endpoint *ep;
903 struct snd_interval *it;
905 ep = get_sync_ep_from_substream(subs);
909 hwc_debug("applying %s\n", __func__);
910 it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
911 return apply_hw_params_minmax(it, ep->cur_period_frames,
912 ep->cur_period_frames);
915 static int hw_rule_periods_implicit_fb(struct snd_pcm_hw_params *params,
916 struct snd_pcm_hw_rule *rule)
918 struct snd_usb_substream *subs = rule->private;
919 const struct snd_usb_endpoint *ep;
920 struct snd_interval *it;
922 ep = get_sync_ep_from_substream(subs);
926 hwc_debug("applying %s\n", __func__);
927 it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIODS);
928 return apply_hw_params_minmax(it, ep->cur_buffer_periods,
929 ep->cur_buffer_periods);
933 * set up the runtime hardware information.
936 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
938 const struct audioformat *fp;
939 unsigned int pt, ptmin;
940 int param_period_time_if_needed = -1;
943 runtime->hw.formats = subs->formats;
945 runtime->hw.rate_min = 0x7fffffff;
946 runtime->hw.rate_max = 0;
947 runtime->hw.channels_min = 256;
948 runtime->hw.channels_max = 0;
949 runtime->hw.rates = 0;
951 /* check min/max rates and channels */
952 list_for_each_entry(fp, &subs->fmt_list, list) {
953 runtime->hw.rates |= fp->rates;
954 if (runtime->hw.rate_min > fp->rate_min)
955 runtime->hw.rate_min = fp->rate_min;
956 if (runtime->hw.rate_max < fp->rate_max)
957 runtime->hw.rate_max = fp->rate_max;
958 if (runtime->hw.channels_min > fp->channels)
959 runtime->hw.channels_min = fp->channels;
960 if (runtime->hw.channels_max < fp->channels)
961 runtime->hw.channels_max = fp->channels;
962 if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
963 /* FIXME: there might be more than one audio formats... */
964 runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
967 pt = 125 * (1 << fp->datainterval);
968 ptmin = min(ptmin, pt);
971 param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
972 if (subs->speed == USB_SPEED_FULL)
973 /* full speed devices have fixed data packet interval */
976 /* if period time doesn't go below 1 ms, no rules needed */
977 param_period_time_if_needed = -1;
979 err = snd_pcm_hw_constraint_minmax(runtime,
980 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
985 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
987 SNDRV_PCM_HW_PARAM_RATE,
988 SNDRV_PCM_HW_PARAM_FORMAT,
989 SNDRV_PCM_HW_PARAM_CHANNELS,
990 param_period_time_if_needed,
995 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
996 hw_rule_channels, subs,
997 SNDRV_PCM_HW_PARAM_CHANNELS,
998 SNDRV_PCM_HW_PARAM_FORMAT,
999 SNDRV_PCM_HW_PARAM_RATE,
1000 param_period_time_if_needed,
1004 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1005 hw_rule_format, subs,
1006 SNDRV_PCM_HW_PARAM_FORMAT,
1007 SNDRV_PCM_HW_PARAM_RATE,
1008 SNDRV_PCM_HW_PARAM_CHANNELS,
1009 param_period_time_if_needed,
1013 if (param_period_time_if_needed >= 0) {
1014 err = snd_pcm_hw_rule_add(runtime, 0,
1015 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1016 hw_rule_period_time, subs,
1017 SNDRV_PCM_HW_PARAM_FORMAT,
1018 SNDRV_PCM_HW_PARAM_CHANNELS,
1019 SNDRV_PCM_HW_PARAM_RATE,
1025 /* additional hw constraints for implicit fb */
1026 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1027 hw_rule_format_implicit_fb, subs,
1028 SNDRV_PCM_HW_PARAM_FORMAT, -1);
1031 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1032 hw_rule_rate_implicit_fb, subs,
1033 SNDRV_PCM_HW_PARAM_RATE, -1);
1036 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
1037 hw_rule_period_size_implicit_fb, subs,
1038 SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
1041 err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
1042 hw_rule_periods_implicit_fb, subs,
1043 SNDRV_PCM_HW_PARAM_PERIODS, -1);
1050 static int snd_usb_pcm_open(struct snd_pcm_substream *substream)
1052 int direction = substream->stream;
1053 struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1054 struct snd_pcm_runtime *runtime = substream->runtime;
1055 struct snd_usb_substream *subs = &as->substream[direction];
1058 runtime->hw = snd_usb_hardware;
1059 runtime->private_data = subs;
1060 subs->pcm_substream = substream;
1061 /* runtime PM is also done there */
1063 /* initialize DSD/DOP context */
1064 subs->dsd_dop.byte_idx = 0;
1065 subs->dsd_dop.channel = 0;
1066 subs->dsd_dop.marker = 1;
1068 ret = setup_hw_info(runtime, subs);
1071 ret = snd_usb_autoresume(subs->stream->chip);
1074 ret = snd_media_stream_init(subs, as->pcm, direction);
1076 snd_usb_autosuspend(subs->stream->chip);
1080 static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
1082 int direction = substream->stream;
1083 struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1084 struct snd_usb_substream *subs = &as->substream[direction];
1087 snd_media_stop_pipeline(subs);
1089 if (!snd_usb_lock_shutdown(subs->stream->chip)) {
1090 ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
1091 snd_usb_unlock_shutdown(subs->stream->chip);
1096 subs->pcm_substream = NULL;
1097 snd_usb_autosuspend(subs->stream->chip);
1102 /* Since a URB can handle only a single linear buffer, we must use double
1103 * buffering when the data to be transferred overflows the buffer boundary.
1104 * To avoid inconsistencies when updating hwptr_done, we use double buffering
1107 static void retire_capture_urb(struct snd_usb_substream *subs,
1110 struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1111 unsigned int stride, frames, bytes, oldptr;
1112 int i, period_elapsed = 0;
1113 unsigned long flags;
1115 int current_frame_number;
1117 /* read frame number here, update pointer in critical section */
1118 current_frame_number = usb_get_current_frame_number(subs->dev);
1120 stride = runtime->frame_bits >> 3;
1122 for (i = 0; i < urb->number_of_packets; i++) {
1123 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1124 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1125 dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1126 i, urb->iso_frame_desc[i].status);
1129 bytes = urb->iso_frame_desc[i].actual_length;
1130 if (subs->stream_offset_adj > 0) {
1131 unsigned int adj = min(subs->stream_offset_adj, bytes);
1134 subs->stream_offset_adj -= adj;
1136 frames = bytes / stride;
1137 if (!subs->txfr_quirk)
1138 bytes = frames * stride;
1139 if (bytes % (runtime->sample_bits >> 3) != 0) {
1140 int oldbytes = bytes;
1141 bytes = frames * stride;
1142 dev_warn_ratelimited(&subs->dev->dev,
1143 "Corrected urb data len. %d->%d\n",
1146 /* update the current pointer */
1147 spin_lock_irqsave(&subs->lock, flags);
1148 oldptr = subs->hwptr_done;
1149 subs->hwptr_done += bytes;
1150 if (subs->hwptr_done >= runtime->buffer_size * stride)
1151 subs->hwptr_done -= runtime->buffer_size * stride;
1152 frames = (bytes + (oldptr % stride)) / stride;
1153 subs->transfer_done += frames;
1154 if (subs->transfer_done >= runtime->period_size) {
1155 subs->transfer_done -= runtime->period_size;
1158 /* capture delay is by construction limited to one URB,
1161 runtime->delay = subs->last_delay = 0;
1163 /* realign last_frame_number */
1164 subs->last_frame_number = current_frame_number;
1165 subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1167 spin_unlock_irqrestore(&subs->lock, flags);
1168 /* copy a data chunk */
1169 if (oldptr + bytes > runtime->buffer_size * stride) {
1170 unsigned int bytes1 =
1171 runtime->buffer_size * stride - oldptr;
1172 memcpy(runtime->dma_area + oldptr, cp, bytes1);
1173 memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1175 memcpy(runtime->dma_area + oldptr, cp, bytes);
1180 snd_pcm_period_elapsed(subs->pcm_substream);
1183 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1184 struct urb *urb, unsigned int bytes)
1186 struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1187 unsigned int stride = runtime->frame_bits >> 3;
1188 unsigned int dst_idx = 0;
1189 unsigned int src_idx = subs->hwptr_done;
1190 unsigned int wrap = runtime->buffer_size * stride;
1191 u8 *dst = urb->transfer_buffer;
1192 u8 *src = runtime->dma_area;
1193 u8 marker[] = { 0x05, 0xfa };
1196 * The DSP DOP format defines a way to transport DSD samples over
1197 * normal PCM data endpoints. It requires stuffing of marker bytes
1198 * (0x05 and 0xfa, alternating per sample frame), and then expects
1199 * 2 additional bytes of actual payload. The whole frame is stored
1202 * Hence, for a stereo transport, the buffer layout looks like this,
1203 * where L refers to left channel samples and R to right.
1205 * L1 L2 0x05 R1 R2 0x05 L3 L4 0xfa R3 R4 0xfa
1206 * L5 L6 0x05 R5 R6 0x05 L7 L8 0xfa R7 R8 0xfa
1212 if (++subs->dsd_dop.byte_idx == 3) {
1213 /* frame boundary? */
1214 dst[dst_idx++] = marker[subs->dsd_dop.marker];
1216 subs->dsd_dop.byte_idx = 0;
1218 if (++subs->dsd_dop.channel % runtime->channels == 0) {
1219 /* alternate the marker */
1220 subs->dsd_dop.marker++;
1221 subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1222 subs->dsd_dop.channel = 0;
1225 /* stuff the DSD payload */
1226 int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1228 if (subs->cur_audiofmt->dsd_bitrev)
1229 dst[dst_idx++] = bitrev8(src[idx]);
1231 dst[dst_idx++] = src[idx];
1236 if (subs->hwptr_done >= runtime->buffer_size * stride)
1237 subs->hwptr_done -= runtime->buffer_size * stride;
1240 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1241 int offset, int stride, unsigned int bytes)
1243 struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1245 if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1246 /* err, the transferred area goes over buffer boundary. */
1247 unsigned int bytes1 =
1248 runtime->buffer_size * stride - subs->hwptr_done;
1249 memcpy(urb->transfer_buffer + offset,
1250 runtime->dma_area + subs->hwptr_done, bytes1);
1251 memcpy(urb->transfer_buffer + offset + bytes1,
1252 runtime->dma_area, bytes - bytes1);
1254 memcpy(urb->transfer_buffer + offset,
1255 runtime->dma_area + subs->hwptr_done, bytes);
1257 subs->hwptr_done += bytes;
1258 if (subs->hwptr_done >= runtime->buffer_size * stride)
1259 subs->hwptr_done -= runtime->buffer_size * stride;
1262 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1263 struct urb *urb, int stride,
1266 __le32 packet_length;
1269 /* Put __le32 length descriptor at start of each packet. */
1270 for (i = 0; i < urb->number_of_packets; i++) {
1271 unsigned int length = urb->iso_frame_desc[i].length;
1272 unsigned int offset = urb->iso_frame_desc[i].offset;
1274 packet_length = cpu_to_le32(length);
1275 offset += i * sizeof(packet_length);
1276 urb->iso_frame_desc[i].offset = offset;
1277 urb->iso_frame_desc[i].length += sizeof(packet_length);
1278 memcpy(urb->transfer_buffer + offset,
1279 &packet_length, sizeof(packet_length));
1280 copy_to_urb(subs, urb, offset + sizeof(packet_length),
1283 /* Adjust transfer size accordingly. */
1284 bytes += urb->number_of_packets * sizeof(packet_length);
1288 static void prepare_playback_urb(struct snd_usb_substream *subs,
1291 struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1292 struct snd_usb_endpoint *ep = subs->data_endpoint;
1293 struct snd_urb_ctx *ctx = urb->context;
1294 unsigned int counts, frames, bytes;
1295 int i, stride, period_elapsed = 0;
1296 unsigned long flags;
1298 stride = runtime->frame_bits >> 3;
1301 urb->number_of_packets = 0;
1302 spin_lock_irqsave(&subs->lock, flags);
1303 subs->frame_limit += ep->max_urb_frames;
1304 for (i = 0; i < ctx->packets; i++) {
1305 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i);
1306 /* set up descriptor */
1307 urb->iso_frame_desc[i].offset = frames * ep->stride;
1308 urb->iso_frame_desc[i].length = counts * ep->stride;
1310 urb->number_of_packets++;
1311 subs->transfer_done += counts;
1312 if (subs->transfer_done >= runtime->period_size) {
1313 subs->transfer_done -= runtime->period_size;
1314 subs->frame_limit = 0;
1316 if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1317 if (subs->transfer_done > 0) {
1318 /* FIXME: fill-max mode is not
1320 frames -= subs->transfer_done;
1321 counts -= subs->transfer_done;
1322 urb->iso_frame_desc[i].length =
1323 counts * ep->stride;
1324 subs->transfer_done = 0;
1327 if (i < ctx->packets) {
1328 /* add a transfer delimiter */
1329 urb->iso_frame_desc[i].offset =
1330 frames * ep->stride;
1331 urb->iso_frame_desc[i].length = 0;
1332 urb->number_of_packets++;
1337 /* finish at the period boundary or after enough frames */
1338 if ((period_elapsed ||
1339 subs->transfer_done >= subs->frame_limit) &&
1340 !snd_usb_endpoint_implicit_feedback_sink(ep))
1343 bytes = frames * ep->stride;
1345 if (unlikely(ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1346 subs->cur_audiofmt->dsd_dop)) {
1347 fill_playback_urb_dsd_dop(subs, urb, bytes);
1348 } else if (unlikely(ep->cur_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1349 subs->cur_audiofmt->dsd_bitrev)) {
1350 /* bit-reverse the bytes */
1351 u8 *buf = urb->transfer_buffer;
1352 for (i = 0; i < bytes; i++) {
1353 int idx = (subs->hwptr_done + i)
1354 % (runtime->buffer_size * stride);
1355 buf[i] = bitrev8(runtime->dma_area[idx]);
1358 subs->hwptr_done += bytes;
1359 if (subs->hwptr_done >= runtime->buffer_size * stride)
1360 subs->hwptr_done -= runtime->buffer_size * stride;
1363 if (!subs->tx_length_quirk)
1364 copy_to_urb(subs, urb, 0, stride, bytes);
1366 bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1367 /* bytes is now amount of outgoing data */
1370 /* update delay with exact number of samples queued */
1371 runtime->delay = subs->last_delay;
1372 runtime->delay += frames;
1373 subs->last_delay = runtime->delay;
1375 /* realign last_frame_number */
1376 subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1377 subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1379 if (subs->trigger_tstamp_pending_update) {
1380 /* this is the first actual URB submitted,
1381 * update trigger timestamp to reflect actual start time
1383 snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1384 subs->trigger_tstamp_pending_update = false;
1387 spin_unlock_irqrestore(&subs->lock, flags);
1388 urb->transfer_buffer_length = bytes;
1390 snd_pcm_period_elapsed(subs->pcm_substream);
1394 * process after playback data complete
1395 * - decrease the delay count again
1397 static void retire_playback_urb(struct snd_usb_substream *subs,
1400 unsigned long flags;
1401 struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1402 struct snd_usb_endpoint *ep = subs->data_endpoint;
1403 int processed = urb->transfer_buffer_length / ep->stride;
1406 /* ignore the delay accounting when processed=0 is given, i.e.
1407 * silent payloads are processed before handling the actual data
1412 spin_lock_irqsave(&subs->lock, flags);
1413 if (!subs->last_delay)
1414 goto out; /* short path */
1416 est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1417 /* update delay with exact number of samples played */
1418 if (processed > subs->last_delay)
1419 subs->last_delay = 0;
1421 subs->last_delay -= processed;
1422 runtime->delay = subs->last_delay;
1425 * Report when delay estimate is off by more than 2ms.
1426 * The error should be lower than 2ms since the estimate relies
1427 * on two reads of a counter updated every ms.
1429 if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1430 dev_dbg_ratelimited(&subs->dev->dev,
1431 "delay: estimated %d, actual %d\n",
1432 est_delay, subs->last_delay);
1434 if (!subs->running) {
1435 /* update last_frame_number for delay counting here since
1436 * prepare_playback_urb won't be called during pause
1438 subs->last_frame_number =
1439 usb_get_current_frame_number(subs->dev) & 0xff;
1443 spin_unlock_irqrestore(&subs->lock, flags);
1446 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1449 struct snd_usb_substream *subs = substream->runtime->private_data;
1452 case SNDRV_PCM_TRIGGER_START:
1453 subs->trigger_tstamp_pending_update = true;
1455 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1456 snd_usb_endpoint_set_callback(subs->data_endpoint,
1457 prepare_playback_urb,
1458 retire_playback_urb,
1461 dev_dbg(&subs->dev->dev, "%d:%d Start Playback PCM\n",
1462 subs->cur_audiofmt->iface,
1463 subs->cur_audiofmt->altsetting);
1465 case SNDRV_PCM_TRIGGER_SUSPEND:
1466 case SNDRV_PCM_TRIGGER_STOP:
1467 stop_endpoints(subs);
1468 snd_usb_endpoint_set_callback(subs->data_endpoint,
1471 dev_dbg(&subs->dev->dev, "%d:%d Stop Playback PCM\n",
1472 subs->cur_audiofmt->iface,
1473 subs->cur_audiofmt->altsetting);
1475 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1476 /* keep retire_data_urb for delay calculation */
1477 snd_usb_endpoint_set_callback(subs->data_endpoint,
1479 retire_playback_urb,
1482 dev_dbg(&subs->dev->dev, "%d:%d Pause Playback PCM\n",
1483 subs->cur_audiofmt->iface,
1484 subs->cur_audiofmt->altsetting);
1491 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1495 struct snd_usb_substream *subs = substream->runtime->private_data;
1498 case SNDRV_PCM_TRIGGER_START:
1499 err = start_endpoints(subs);
1503 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1504 snd_usb_endpoint_set_callback(subs->data_endpoint,
1505 NULL, retire_capture_urb,
1508 dev_dbg(&subs->dev->dev, "%d:%d Start Capture PCM\n",
1509 subs->cur_audiofmt->iface,
1510 subs->cur_audiofmt->altsetting);
1512 case SNDRV_PCM_TRIGGER_SUSPEND:
1513 case SNDRV_PCM_TRIGGER_STOP:
1514 stop_endpoints(subs);
1516 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1517 snd_usb_endpoint_set_callback(subs->data_endpoint,
1520 dev_dbg(&subs->dev->dev, "%d:%d Stop Capture PCM\n",
1521 subs->cur_audiofmt->iface,
1522 subs->cur_audiofmt->altsetting);
1529 static const struct snd_pcm_ops snd_usb_playback_ops = {
1530 .open = snd_usb_pcm_open,
1531 .close = snd_usb_pcm_close,
1532 .hw_params = snd_usb_hw_params,
1533 .hw_free = snd_usb_hw_free,
1534 .prepare = snd_usb_pcm_prepare,
1535 .trigger = snd_usb_substream_playback_trigger,
1536 .sync_stop = snd_usb_pcm_sync_stop,
1537 .pointer = snd_usb_pcm_pointer,
1540 static const struct snd_pcm_ops snd_usb_capture_ops = {
1541 .open = snd_usb_pcm_open,
1542 .close = snd_usb_pcm_close,
1543 .hw_params = snd_usb_hw_params,
1544 .hw_free = snd_usb_hw_free,
1545 .prepare = snd_usb_pcm_prepare,
1546 .trigger = snd_usb_substream_capture_trigger,
1547 .sync_stop = snd_usb_pcm_sync_stop,
1548 .pointer = snd_usb_pcm_pointer,
1551 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1553 const struct snd_pcm_ops *ops;
1555 ops = stream == SNDRV_PCM_STREAM_PLAYBACK ?
1556 &snd_usb_playback_ops : &snd_usb_capture_ops;
1557 snd_pcm_set_ops(pcm, stream, ops);
1560 void snd_usb_preallocate_buffer(struct snd_usb_substream *subs)
1562 struct snd_pcm *pcm = subs->stream->pcm;
1563 struct snd_pcm_substream *s = pcm->streams[subs->direction].substream;
1564 struct device *dev = subs->dev->bus->sysdev;
1566 if (snd_usb_use_vmalloc)
1567 snd_pcm_set_managed_buffer(s, SNDRV_DMA_TYPE_VMALLOC,
1570 snd_pcm_set_managed_buffer(s, SNDRV_DMA_TYPE_DEV_SG,
1571 dev, 64*1024, 512*1024);