xref: /openbmc/linux/sound/usb/pcm.c (revision 95e9fd10)
1 /*
2  *   This program is free software; you can redistribute it and/or modify
3  *   it under the terms of the GNU General Public License as published by
4  *   the Free Software Foundation; either version 2 of the License, or
5  *   (at your option) any later version.
6  *
7  *   This program is distributed in the hope that it will be useful,
8  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
9  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  *   GNU General Public License for more details.
11  *
12  *   You should have received a copy of the GNU General Public License
13  *   along with this program; if not, write to the Free Software
14  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
15  */
16 
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/ratelimit.h>
20 #include <linux/usb.h>
21 #include <linux/usb/audio.h>
22 #include <linux/usb/audio-v2.h>
23 
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 
28 #include "usbaudio.h"
29 #include "card.h"
30 #include "quirks.h"
31 #include "debug.h"
32 #include "endpoint.h"
33 #include "helper.h"
34 #include "pcm.h"
35 #include "clock.h"
36 #include "power.h"
37 
38 #define SUBSTREAM_FLAG_DATA_EP_STARTED	0
39 #define SUBSTREAM_FLAG_SYNC_EP_STARTED	1
40 
41 /* return the estimated delay based on USB frame counters */
42 snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,
43 				    unsigned int rate)
44 {
45 	int current_frame_number;
46 	int frame_diff;
47 	int est_delay;
48 
49 	current_frame_number = usb_get_current_frame_number(subs->dev);
50 	/*
51 	 * HCD implementations use different widths, use lower 8 bits.
52 	 * The delay will be managed up to 256ms, which is more than
53 	 * enough
54 	 */
55 	frame_diff = (current_frame_number - subs->last_frame_number) & 0xff;
56 
57 	/* Approximation based on number of samples per USB frame (ms),
58 	   some truncation for 44.1 but the estimate is good enough */
59 	est_delay =  subs->last_delay - (frame_diff * rate / 1000);
60 	if (est_delay < 0)
61 		est_delay = 0;
62 	return est_delay;
63 }
64 
65 /*
66  * return the current pcm pointer.  just based on the hwptr_done value.
67  */
68 static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream)
69 {
70 	struct snd_usb_substream *subs;
71 	unsigned int hwptr_done;
72 
73 	subs = (struct snd_usb_substream *)substream->runtime->private_data;
74 	spin_lock(&subs->lock);
75 	hwptr_done = subs->hwptr_done;
76 	substream->runtime->delay = snd_usb_pcm_delay(subs,
77 						substream->runtime->rate);
78 	spin_unlock(&subs->lock);
79 	return hwptr_done / (substream->runtime->frame_bits >> 3);
80 }
81 
82 /*
83  * find a matching audio format
84  */
85 static struct audioformat *find_format(struct snd_usb_substream *subs, unsigned int format,
86 				       unsigned int rate, unsigned int channels)
87 {
88 	struct list_head *p;
89 	struct audioformat *found = NULL;
90 	int cur_attr = 0, attr;
91 
92 	list_for_each(p, &subs->fmt_list) {
93 		struct audioformat *fp;
94 		fp = list_entry(p, struct audioformat, list);
95 		if (!(fp->formats & (1uLL << format)))
96 			continue;
97 		if (fp->channels != channels)
98 			continue;
99 		if (rate < fp->rate_min || rate > fp->rate_max)
100 			continue;
101 		if (! (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
102 			unsigned int i;
103 			for (i = 0; i < fp->nr_rates; i++)
104 				if (fp->rate_table[i] == rate)
105 					break;
106 			if (i >= fp->nr_rates)
107 				continue;
108 		}
109 		attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
110 		if (! found) {
111 			found = fp;
112 			cur_attr = attr;
113 			continue;
114 		}
115 		/* avoid async out and adaptive in if the other method
116 		 * supports the same format.
117 		 * this is a workaround for the case like
118 		 * M-audio audiophile USB.
119 		 */
120 		if (attr != cur_attr) {
121 			if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
122 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
123 			    (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
124 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE))
125 				continue;
126 			if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
127 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
128 			    (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
129 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
130 				found = fp;
131 				cur_attr = attr;
132 				continue;
133 			}
134 		}
135 		/* find the format with the largest max. packet size */
136 		if (fp->maxpacksize > found->maxpacksize) {
137 			found = fp;
138 			cur_attr = attr;
139 		}
140 	}
141 	return found;
142 }
143 
144 static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
145 			 struct usb_host_interface *alts,
146 			 struct audioformat *fmt)
147 {
148 	struct usb_device *dev = chip->dev;
149 	unsigned int ep;
150 	unsigned char data[1];
151 	int err;
152 
153 	ep = get_endpoint(alts, 0)->bEndpointAddress;
154 
155 	data[0] = 1;
156 	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
157 				   USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
158 				   UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
159 				   data, sizeof(data))) < 0) {
160 		snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH\n",
161 			   dev->devnum, iface, ep);
162 		return err;
163 	}
164 
165 	return 0;
166 }
167 
168 static int init_pitch_v2(struct snd_usb_audio *chip, int iface,
169 			 struct usb_host_interface *alts,
170 			 struct audioformat *fmt)
171 {
172 	struct usb_device *dev = chip->dev;
173 	unsigned char data[1];
174 	unsigned int ep;
175 	int err;
176 
177 	ep = get_endpoint(alts, 0)->bEndpointAddress;
178 
179 	data[0] = 1;
180 	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
181 				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
182 				   UAC2_EP_CS_PITCH << 8, 0,
183 				   data, sizeof(data))) < 0) {
184 		snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH (v2)\n",
185 			   dev->devnum, iface, fmt->altsetting);
186 		return err;
187 	}
188 
189 	return 0;
190 }
191 
192 /*
193  * initialize the pitch control and sample rate
194  */
195 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
196 		       struct usb_host_interface *alts,
197 		       struct audioformat *fmt)
198 {
199 	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
200 
201 	/* if endpoint doesn't have pitch control, bail out */
202 	if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
203 		return 0;
204 
205 	switch (altsd->bInterfaceProtocol) {
206 	case UAC_VERSION_1:
207 	default:
208 		return init_pitch_v1(chip, iface, alts, fmt);
209 
210 	case UAC_VERSION_2:
211 		return init_pitch_v2(chip, iface, alts, fmt);
212 	}
213 }
214 
215 static int start_endpoints(struct snd_usb_substream *subs, int can_sleep)
216 {
217 	int err;
218 
219 	if (!subs->data_endpoint)
220 		return -EINVAL;
221 
222 	if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
223 		struct snd_usb_endpoint *ep = subs->data_endpoint;
224 
225 		snd_printdd(KERN_DEBUG "Starting data EP @%p\n", ep);
226 
227 		ep->data_subs = subs;
228 		err = snd_usb_endpoint_start(ep, can_sleep);
229 		if (err < 0) {
230 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
231 			return err;
232 		}
233 	}
234 
235 	if (subs->sync_endpoint &&
236 	    !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
237 		struct snd_usb_endpoint *ep = subs->sync_endpoint;
238 
239 		if (subs->data_endpoint->iface != subs->sync_endpoint->iface ||
240 		    subs->data_endpoint->alt_idx != subs->sync_endpoint->alt_idx) {
241 			err = usb_set_interface(subs->dev,
242 						subs->sync_endpoint->iface,
243 						subs->sync_endpoint->alt_idx);
244 			if (err < 0) {
245 				snd_printk(KERN_ERR
246 					   "%d:%d:%d: cannot set interface (%d)\n",
247 					   subs->dev->devnum,
248 					   subs->sync_endpoint->iface,
249 					   subs->sync_endpoint->alt_idx, err);
250 				return -EIO;
251 			}
252 		}
253 
254 		snd_printdd(KERN_DEBUG "Starting sync EP @%p\n", ep);
255 
256 		ep->sync_slave = subs->data_endpoint;
257 		err = snd_usb_endpoint_start(ep, can_sleep);
258 		if (err < 0) {
259 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
260 			return err;
261 		}
262 	}
263 
264 	return 0;
265 }
266 
267 static void stop_endpoints(struct snd_usb_substream *subs,
268 			   int force, int can_sleep, int wait)
269 {
270 	if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags))
271 		snd_usb_endpoint_stop(subs->sync_endpoint,
272 				      force, can_sleep, wait);
273 
274 	if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags))
275 		snd_usb_endpoint_stop(subs->data_endpoint,
276 				      force, can_sleep, wait);
277 }
278 
279 static int deactivate_endpoints(struct snd_usb_substream *subs)
280 {
281 	int reta, retb;
282 
283 	reta = snd_usb_endpoint_deactivate(subs->sync_endpoint);
284 	retb = snd_usb_endpoint_deactivate(subs->data_endpoint);
285 
286 	if (reta < 0)
287 		return reta;
288 
289 	if (retb < 0)
290 		return retb;
291 
292 	return 0;
293 }
294 
295 /*
296  * find a matching format and set up the interface
297  */
298 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
299 {
300 	struct usb_device *dev = subs->dev;
301 	struct usb_host_interface *alts;
302 	struct usb_interface_descriptor *altsd;
303 	struct usb_interface *iface;
304 	unsigned int ep, attr;
305 	int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
306 	int err, implicit_fb = 0;
307 
308 	iface = usb_ifnum_to_if(dev, fmt->iface);
309 	if (WARN_ON(!iface))
310 		return -EINVAL;
311 	alts = &iface->altsetting[fmt->altset_idx];
312 	altsd = get_iface_desc(alts);
313 	if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
314 		return -EINVAL;
315 
316 	if (fmt == subs->cur_audiofmt)
317 		return 0;
318 
319 	/* close the old interface */
320 	if (subs->interface >= 0 && subs->interface != fmt->iface) {
321 		err = usb_set_interface(subs->dev, subs->interface, 0);
322 		if (err < 0) {
323 			snd_printk(KERN_ERR "%d:%d:%d: return to setting 0 failed (%d)\n",
324 				dev->devnum, fmt->iface, fmt->altsetting, err);
325 			return -EIO;
326 		}
327 		subs->interface = -1;
328 		subs->altset_idx = 0;
329 	}
330 
331 	/* set interface */
332 	if (subs->interface != fmt->iface ||
333 	    subs->altset_idx != fmt->altset_idx) {
334 		err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
335 		if (err < 0) {
336 			snd_printk(KERN_ERR "%d:%d:%d: usb_set_interface failed (%d)\n",
337 				   dev->devnum, fmt->iface, fmt->altsetting, err);
338 			return -EIO;
339 		}
340 		snd_printdd(KERN_INFO "setting usb interface %d:%d\n",
341 				fmt->iface, fmt->altsetting);
342 		subs->interface = fmt->iface;
343 		subs->altset_idx = fmt->altset_idx;
344 	}
345 
346 	subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
347 						   alts, fmt->endpoint, subs->direction,
348 						   SND_USB_ENDPOINT_TYPE_DATA);
349 	if (!subs->data_endpoint)
350 		return -EINVAL;
351 
352 	/* we need a sync pipe in async OUT or adaptive IN mode */
353 	/* check the number of EP, since some devices have broken
354 	 * descriptors which fool us.  if it has only one EP,
355 	 * assume it as adaptive-out or sync-in.
356 	 */
357 	attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
358 
359 	switch (subs->stream->chip->usb_id) {
360 	case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
361 	case USB_ID(0x0763, 0x2081):
362 		if (is_playback) {
363 			implicit_fb = 1;
364 			ep = 0x81;
365 			iface = usb_ifnum_to_if(dev, 2);
366 
367 			if (!iface || iface->num_altsetting == 0)
368 				return -EINVAL;
369 
370 			alts = &iface->altsetting[1];
371 			goto add_sync_ep;
372 		}
373 	}
374 
375 	if (((is_playback && attr == USB_ENDPOINT_SYNC_ASYNC) ||
376 	     (!is_playback && attr == USB_ENDPOINT_SYNC_ADAPTIVE)) &&
377 	    altsd->bNumEndpoints >= 2) {
378 		/* check sync-pipe endpoint */
379 		/* ... and check descriptor size before accessing bSynchAddress
380 		   because there is a version of the SB Audigy 2 NX firmware lacking
381 		   the audio fields in the endpoint descriptors */
382 		if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != 0x01 ||
383 		    (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
384 		     get_endpoint(alts, 1)->bSynchAddress != 0 &&
385 		     !implicit_fb)) {
386 			snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
387 				   dev->devnum, fmt->iface, fmt->altsetting,
388 				   get_endpoint(alts, 1)->bmAttributes,
389 				   get_endpoint(alts, 1)->bLength,
390 				   get_endpoint(alts, 1)->bSynchAddress);
391 			return -EINVAL;
392 		}
393 		ep = get_endpoint(alts, 1)->bEndpointAddress;
394 		if (!implicit_fb &&
395 		    get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
396 		    (( is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
397 		     (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
398 			snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
399 				   dev->devnum, fmt->iface, fmt->altsetting,
400 				   is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
401 			return -EINVAL;
402 		}
403 
404 		implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
405 				== USB_ENDPOINT_USAGE_IMPLICIT_FB;
406 
407 add_sync_ep:
408 		subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
409 							   alts, ep, !subs->direction,
410 							   implicit_fb ?
411 								SND_USB_ENDPOINT_TYPE_DATA :
412 								SND_USB_ENDPOINT_TYPE_SYNC);
413 		if (!subs->sync_endpoint)
414 			return -EINVAL;
415 
416 		subs->data_endpoint->sync_master = subs->sync_endpoint;
417 	}
418 
419 	if ((err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt)) < 0)
420 		return err;
421 
422 	subs->cur_audiofmt = fmt;
423 
424 	snd_usb_set_format_quirk(subs, fmt);
425 
426 #if 0
427 	printk(KERN_DEBUG
428 	       "setting done: format = %d, rate = %d..%d, channels = %d\n",
429 	       fmt->format, fmt->rate_min, fmt->rate_max, fmt->channels);
430 	printk(KERN_DEBUG
431 	       "  datapipe = 0x%0x, syncpipe = 0x%0x\n",
432 	       subs->datapipe, subs->syncpipe);
433 #endif
434 
435 	return 0;
436 }
437 
438 /*
439  * hw_params callback
440  *
441  * allocate a buffer and set the given audio format.
442  *
443  * so far we use a physically linear buffer although packetize transfer
444  * doesn't need a continuous area.
445  * if sg buffer is supported on the later version of alsa, we'll follow
446  * that.
447  */
448 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
449 			     struct snd_pcm_hw_params *hw_params)
450 {
451 	struct snd_usb_substream *subs = substream->runtime->private_data;
452 	struct audioformat *fmt;
453 	unsigned int channels, rate, format;
454 	int ret, changed;
455 
456 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
457 					       params_buffer_bytes(hw_params));
458 	if (ret < 0)
459 		return ret;
460 
461 	format = params_format(hw_params);
462 	rate = params_rate(hw_params);
463 	channels = params_channels(hw_params);
464 	fmt = find_format(subs, format, rate, channels);
465 	if (!fmt) {
466 		snd_printd(KERN_DEBUG "cannot set format: format = %#x, rate = %d, channels = %d\n",
467 			   format, rate, channels);
468 		return -EINVAL;
469 	}
470 
471 	changed = subs->cur_audiofmt != fmt ||
472 		subs->period_bytes != params_period_bytes(hw_params) ||
473 		subs->cur_rate != rate;
474 	if ((ret = set_format(subs, fmt)) < 0)
475 		return ret;
476 
477 	if (subs->cur_rate != rate) {
478 		struct usb_host_interface *alts;
479 		struct usb_interface *iface;
480 		iface = usb_ifnum_to_if(subs->dev, fmt->iface);
481 		alts = &iface->altsetting[fmt->altset_idx];
482 		ret = snd_usb_init_sample_rate(subs->stream->chip, fmt->iface, alts, fmt, rate);
483 		if (ret < 0)
484 			return ret;
485 		subs->cur_rate = rate;
486 	}
487 
488 	if (changed) {
489 		mutex_lock(&subs->stream->chip->shutdown_mutex);
490 		/* format changed */
491 		stop_endpoints(subs, 0, 0, 0);
492 		ret = snd_usb_endpoint_set_params(subs->data_endpoint, hw_params, fmt,
493 						  subs->sync_endpoint);
494 		if (ret < 0)
495 			goto unlock;
496 
497 		if (subs->sync_endpoint)
498 			ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
499 							  hw_params, fmt, NULL);
500 unlock:
501 		mutex_unlock(&subs->stream->chip->shutdown_mutex);
502 	}
503 
504 	if (ret == 0) {
505 		subs->interface = fmt->iface;
506 		subs->altset_idx = fmt->altset_idx;
507 	}
508 
509 	return ret;
510 }
511 
512 /*
513  * hw_free callback
514  *
515  * reset the audio format and release the buffer
516  */
517 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
518 {
519 	struct snd_usb_substream *subs = substream->runtime->private_data;
520 
521 	subs->cur_audiofmt = NULL;
522 	subs->cur_rate = 0;
523 	subs->period_bytes = 0;
524 	mutex_lock(&subs->stream->chip->shutdown_mutex);
525 	stop_endpoints(subs, 0, 1, 1);
526 	deactivate_endpoints(subs);
527 	mutex_unlock(&subs->stream->chip->shutdown_mutex);
528 	return snd_pcm_lib_free_vmalloc_buffer(substream);
529 }
530 
531 /*
532  * prepare callback
533  *
534  * only a few subtle things...
535  */
536 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
537 {
538 	struct snd_pcm_runtime *runtime = substream->runtime;
539 	struct snd_usb_substream *subs = runtime->private_data;
540 
541 	if (! subs->cur_audiofmt) {
542 		snd_printk(KERN_ERR "usbaudio: no format is specified!\n");
543 		return -ENXIO;
544 	}
545 
546 	if (snd_BUG_ON(!subs->data_endpoint))
547 		return -EIO;
548 
549 	/* some unit conversions in runtime */
550 	subs->data_endpoint->maxframesize =
551 		bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
552 	subs->data_endpoint->curframesize =
553 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
554 
555 	/* reset the pointer */
556 	subs->hwptr_done = 0;
557 	subs->transfer_done = 0;
558 	subs->last_delay = 0;
559 	subs->last_frame_number = 0;
560 	runtime->delay = 0;
561 
562 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
563 	 * updates for all URBs would happen at the same time when starting */
564 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
565 		return start_endpoints(subs, 1);
566 
567 	return 0;
568 }
569 
570 static struct snd_pcm_hardware snd_usb_hardware =
571 {
572 	.info =			SNDRV_PCM_INFO_MMAP |
573 				SNDRV_PCM_INFO_MMAP_VALID |
574 				SNDRV_PCM_INFO_BATCH |
575 				SNDRV_PCM_INFO_INTERLEAVED |
576 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
577 				SNDRV_PCM_INFO_PAUSE,
578 	.buffer_bytes_max =	1024 * 1024,
579 	.period_bytes_min =	64,
580 	.period_bytes_max =	512 * 1024,
581 	.periods_min =		2,
582 	.periods_max =		1024,
583 };
584 
585 static int hw_check_valid_format(struct snd_usb_substream *subs,
586 				 struct snd_pcm_hw_params *params,
587 				 struct audioformat *fp)
588 {
589 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
590 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
591 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
592 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
593 	struct snd_mask check_fmts;
594 	unsigned int ptime;
595 
596 	/* check the format */
597 	snd_mask_none(&check_fmts);
598 	check_fmts.bits[0] = (u32)fp->formats;
599 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
600 	snd_mask_intersect(&check_fmts, fmts);
601 	if (snd_mask_empty(&check_fmts)) {
602 		hwc_debug("   > check: no supported format %d\n", fp->format);
603 		return 0;
604 	}
605 	/* check the channels */
606 	if (fp->channels < ct->min || fp->channels > ct->max) {
607 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
608 		return 0;
609 	}
610 	/* check the rate is within the range */
611 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
612 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
613 		return 0;
614 	}
615 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
616 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
617 		return 0;
618 	}
619 	/* check whether the period time is >= the data packet interval */
620 	if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL) {
621 		ptime = 125 * (1 << fp->datainterval);
622 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
623 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
624 			return 0;
625 		}
626 	}
627 	return 1;
628 }
629 
630 static int hw_rule_rate(struct snd_pcm_hw_params *params,
631 			struct snd_pcm_hw_rule *rule)
632 {
633 	struct snd_usb_substream *subs = rule->private;
634 	struct list_head *p;
635 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
636 	unsigned int rmin, rmax;
637 	int changed;
638 
639 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
640 	changed = 0;
641 	rmin = rmax = 0;
642 	list_for_each(p, &subs->fmt_list) {
643 		struct audioformat *fp;
644 		fp = list_entry(p, struct audioformat, list);
645 		if (!hw_check_valid_format(subs, params, fp))
646 			continue;
647 		if (changed++) {
648 			if (rmin > fp->rate_min)
649 				rmin = fp->rate_min;
650 			if (rmax < fp->rate_max)
651 				rmax = fp->rate_max;
652 		} else {
653 			rmin = fp->rate_min;
654 			rmax = fp->rate_max;
655 		}
656 	}
657 
658 	if (!changed) {
659 		hwc_debug("  --> get empty\n");
660 		it->empty = 1;
661 		return -EINVAL;
662 	}
663 
664 	changed = 0;
665 	if (it->min < rmin) {
666 		it->min = rmin;
667 		it->openmin = 0;
668 		changed = 1;
669 	}
670 	if (it->max > rmax) {
671 		it->max = rmax;
672 		it->openmax = 0;
673 		changed = 1;
674 	}
675 	if (snd_interval_checkempty(it)) {
676 		it->empty = 1;
677 		return -EINVAL;
678 	}
679 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
680 	return changed;
681 }
682 
683 
684 static int hw_rule_channels(struct snd_pcm_hw_params *params,
685 			    struct snd_pcm_hw_rule *rule)
686 {
687 	struct snd_usb_substream *subs = rule->private;
688 	struct list_head *p;
689 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
690 	unsigned int rmin, rmax;
691 	int changed;
692 
693 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
694 	changed = 0;
695 	rmin = rmax = 0;
696 	list_for_each(p, &subs->fmt_list) {
697 		struct audioformat *fp;
698 		fp = list_entry(p, struct audioformat, list);
699 		if (!hw_check_valid_format(subs, params, fp))
700 			continue;
701 		if (changed++) {
702 			if (rmin > fp->channels)
703 				rmin = fp->channels;
704 			if (rmax < fp->channels)
705 				rmax = fp->channels;
706 		} else {
707 			rmin = fp->channels;
708 			rmax = fp->channels;
709 		}
710 	}
711 
712 	if (!changed) {
713 		hwc_debug("  --> get empty\n");
714 		it->empty = 1;
715 		return -EINVAL;
716 	}
717 
718 	changed = 0;
719 	if (it->min < rmin) {
720 		it->min = rmin;
721 		it->openmin = 0;
722 		changed = 1;
723 	}
724 	if (it->max > rmax) {
725 		it->max = rmax;
726 		it->openmax = 0;
727 		changed = 1;
728 	}
729 	if (snd_interval_checkempty(it)) {
730 		it->empty = 1;
731 		return -EINVAL;
732 	}
733 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
734 	return changed;
735 }
736 
737 static int hw_rule_format(struct snd_pcm_hw_params *params,
738 			  struct snd_pcm_hw_rule *rule)
739 {
740 	struct snd_usb_substream *subs = rule->private;
741 	struct list_head *p;
742 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
743 	u64 fbits;
744 	u32 oldbits[2];
745 	int changed;
746 
747 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
748 	fbits = 0;
749 	list_for_each(p, &subs->fmt_list) {
750 		struct audioformat *fp;
751 		fp = list_entry(p, struct audioformat, list);
752 		if (!hw_check_valid_format(subs, params, fp))
753 			continue;
754 		fbits |= fp->formats;
755 	}
756 
757 	oldbits[0] = fmt->bits[0];
758 	oldbits[1] = fmt->bits[1];
759 	fmt->bits[0] &= (u32)fbits;
760 	fmt->bits[1] &= (u32)(fbits >> 32);
761 	if (!fmt->bits[0] && !fmt->bits[1]) {
762 		hwc_debug("  --> get empty\n");
763 		return -EINVAL;
764 	}
765 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
766 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
767 	return changed;
768 }
769 
770 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
771 			       struct snd_pcm_hw_rule *rule)
772 {
773 	struct snd_usb_substream *subs = rule->private;
774 	struct audioformat *fp;
775 	struct snd_interval *it;
776 	unsigned char min_datainterval;
777 	unsigned int pmin;
778 	int changed;
779 
780 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
781 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
782 	min_datainterval = 0xff;
783 	list_for_each_entry(fp, &subs->fmt_list, list) {
784 		if (!hw_check_valid_format(subs, params, fp))
785 			continue;
786 		min_datainterval = min(min_datainterval, fp->datainterval);
787 	}
788 	if (min_datainterval == 0xff) {
789 		hwc_debug("  --> get empty\n");
790 		it->empty = 1;
791 		return -EINVAL;
792 	}
793 	pmin = 125 * (1 << min_datainterval);
794 	changed = 0;
795 	if (it->min < pmin) {
796 		it->min = pmin;
797 		it->openmin = 0;
798 		changed = 1;
799 	}
800 	if (snd_interval_checkempty(it)) {
801 		it->empty = 1;
802 		return -EINVAL;
803 	}
804 	hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
805 	return changed;
806 }
807 
808 /*
809  *  If the device supports unusual bit rates, does the request meet these?
810  */
811 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
812 				  struct snd_usb_substream *subs)
813 {
814 	struct audioformat *fp;
815 	int *rate_list;
816 	int count = 0, needs_knot = 0;
817 	int err;
818 
819 	kfree(subs->rate_list.list);
820 	subs->rate_list.list = NULL;
821 
822 	list_for_each_entry(fp, &subs->fmt_list, list) {
823 		if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
824 			return 0;
825 		count += fp->nr_rates;
826 		if (fp->rates & SNDRV_PCM_RATE_KNOT)
827 			needs_knot = 1;
828 	}
829 	if (!needs_knot)
830 		return 0;
831 
832 	subs->rate_list.list = rate_list =
833 		kmalloc(sizeof(int) * count, GFP_KERNEL);
834 	if (!subs->rate_list.list)
835 		return -ENOMEM;
836 	subs->rate_list.count = count;
837 	subs->rate_list.mask = 0;
838 	count = 0;
839 	list_for_each_entry(fp, &subs->fmt_list, list) {
840 		int i;
841 		for (i = 0; i < fp->nr_rates; i++)
842 			rate_list[count++] = fp->rate_table[i];
843 	}
844 	err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
845 					 &subs->rate_list);
846 	if (err < 0)
847 		return err;
848 
849 	return 0;
850 }
851 
852 
853 /*
854  * set up the runtime hardware information.
855  */
856 
857 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
858 {
859 	struct list_head *p;
860 	unsigned int pt, ptmin;
861 	int param_period_time_if_needed;
862 	int err;
863 
864 	runtime->hw.formats = subs->formats;
865 
866 	runtime->hw.rate_min = 0x7fffffff;
867 	runtime->hw.rate_max = 0;
868 	runtime->hw.channels_min = 256;
869 	runtime->hw.channels_max = 0;
870 	runtime->hw.rates = 0;
871 	ptmin = UINT_MAX;
872 	/* check min/max rates and channels */
873 	list_for_each(p, &subs->fmt_list) {
874 		struct audioformat *fp;
875 		fp = list_entry(p, struct audioformat, list);
876 		runtime->hw.rates |= fp->rates;
877 		if (runtime->hw.rate_min > fp->rate_min)
878 			runtime->hw.rate_min = fp->rate_min;
879 		if (runtime->hw.rate_max < fp->rate_max)
880 			runtime->hw.rate_max = fp->rate_max;
881 		if (runtime->hw.channels_min > fp->channels)
882 			runtime->hw.channels_min = fp->channels;
883 		if (runtime->hw.channels_max < fp->channels)
884 			runtime->hw.channels_max = fp->channels;
885 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
886 			/* FIXME: there might be more than one audio formats... */
887 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
888 				fp->frame_size;
889 		}
890 		pt = 125 * (1 << fp->datainterval);
891 		ptmin = min(ptmin, pt);
892 	}
893 	err = snd_usb_autoresume(subs->stream->chip);
894 	if (err < 0)
895 		return err;
896 
897 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
898 	if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
899 		/* full speed devices have fixed data packet interval */
900 		ptmin = 1000;
901 	if (ptmin == 1000)
902 		/* if period time doesn't go below 1 ms, no rules needed */
903 		param_period_time_if_needed = -1;
904 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
905 				     ptmin, UINT_MAX);
906 
907 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
908 				       hw_rule_rate, subs,
909 				       SNDRV_PCM_HW_PARAM_FORMAT,
910 				       SNDRV_PCM_HW_PARAM_CHANNELS,
911 				       param_period_time_if_needed,
912 				       -1)) < 0)
913 		goto rep_err;
914 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
915 				       hw_rule_channels, subs,
916 				       SNDRV_PCM_HW_PARAM_FORMAT,
917 				       SNDRV_PCM_HW_PARAM_RATE,
918 				       param_period_time_if_needed,
919 				       -1)) < 0)
920 		goto rep_err;
921 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
922 				       hw_rule_format, subs,
923 				       SNDRV_PCM_HW_PARAM_RATE,
924 				       SNDRV_PCM_HW_PARAM_CHANNELS,
925 				       param_period_time_if_needed,
926 				       -1)) < 0)
927 		goto rep_err;
928 	if (param_period_time_if_needed >= 0) {
929 		err = snd_pcm_hw_rule_add(runtime, 0,
930 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
931 					  hw_rule_period_time, subs,
932 					  SNDRV_PCM_HW_PARAM_FORMAT,
933 					  SNDRV_PCM_HW_PARAM_CHANNELS,
934 					  SNDRV_PCM_HW_PARAM_RATE,
935 					  -1);
936 		if (err < 0)
937 			goto rep_err;
938 	}
939 	if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
940 		goto rep_err;
941 	return 0;
942 
943 rep_err:
944 	snd_usb_autosuspend(subs->stream->chip);
945 	return err;
946 }
947 
948 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
949 {
950 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
951 	struct snd_pcm_runtime *runtime = substream->runtime;
952 	struct snd_usb_substream *subs = &as->substream[direction];
953 
954 	subs->interface = -1;
955 	subs->altset_idx = 0;
956 	runtime->hw = snd_usb_hardware;
957 	runtime->private_data = subs;
958 	subs->pcm_substream = substream;
959 	/* runtime PM is also done there */
960 	return setup_hw_info(runtime, subs);
961 }
962 
963 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
964 {
965 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
966 	struct snd_usb_substream *subs = &as->substream[direction];
967 
968 	stop_endpoints(subs, 0, 0, 0);
969 
970 	if (!as->chip->shutdown && subs->interface >= 0) {
971 		usb_set_interface(subs->dev, subs->interface, 0);
972 		subs->interface = -1;
973 	}
974 
975 	subs->pcm_substream = NULL;
976 	snd_usb_autosuspend(subs->stream->chip);
977 
978 	return 0;
979 }
980 
981 /* Since a URB can handle only a single linear buffer, we must use double
982  * buffering when the data to be transferred overflows the buffer boundary.
983  * To avoid inconsistencies when updating hwptr_done, we use double buffering
984  * for all URBs.
985  */
986 static void retire_capture_urb(struct snd_usb_substream *subs,
987 			       struct urb *urb)
988 {
989 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
990 	unsigned int stride, frames, bytes, oldptr;
991 	int i, period_elapsed = 0;
992 	unsigned long flags;
993 	unsigned char *cp;
994 
995 	stride = runtime->frame_bits >> 3;
996 
997 	for (i = 0; i < urb->number_of_packets; i++) {
998 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
999 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1000 			snd_printdd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
1001 			// continue;
1002 		}
1003 		bytes = urb->iso_frame_desc[i].actual_length;
1004 		frames = bytes / stride;
1005 		if (!subs->txfr_quirk)
1006 			bytes = frames * stride;
1007 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1008 #ifdef CONFIG_SND_DEBUG_VERBOSE
1009 			int oldbytes = bytes;
1010 #endif
1011 			bytes = frames * stride;
1012 			snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
1013 							oldbytes, bytes);
1014 		}
1015 		/* update the current pointer */
1016 		spin_lock_irqsave(&subs->lock, flags);
1017 		oldptr = subs->hwptr_done;
1018 		subs->hwptr_done += bytes;
1019 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1020 			subs->hwptr_done -= runtime->buffer_size * stride;
1021 		frames = (bytes + (oldptr % stride)) / stride;
1022 		subs->transfer_done += frames;
1023 		if (subs->transfer_done >= runtime->period_size) {
1024 			subs->transfer_done -= runtime->period_size;
1025 			period_elapsed = 1;
1026 		}
1027 		spin_unlock_irqrestore(&subs->lock, flags);
1028 		/* copy a data chunk */
1029 		if (oldptr + bytes > runtime->buffer_size * stride) {
1030 			unsigned int bytes1 =
1031 					runtime->buffer_size * stride - oldptr;
1032 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1033 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1034 		} else {
1035 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1036 		}
1037 	}
1038 
1039 	if (period_elapsed)
1040 		snd_pcm_period_elapsed(subs->pcm_substream);
1041 }
1042 
1043 static void prepare_playback_urb(struct snd_usb_substream *subs,
1044 				 struct urb *urb)
1045 {
1046 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1047 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1048 	struct snd_urb_ctx *ctx = urb->context;
1049 	unsigned int counts, frames, bytes;
1050 	int i, stride, period_elapsed = 0;
1051 	unsigned long flags;
1052 
1053 	stride = runtime->frame_bits >> 3;
1054 
1055 	frames = 0;
1056 	urb->number_of_packets = 0;
1057 	spin_lock_irqsave(&subs->lock, flags);
1058 	for (i = 0; i < ctx->packets; i++) {
1059 		if (ctx->packet_size[i])
1060 			counts = ctx->packet_size[i];
1061 		else
1062 			counts = snd_usb_endpoint_next_packet_size(ep);
1063 
1064 		/* set up descriptor */
1065 		urb->iso_frame_desc[i].offset = frames * stride;
1066 		urb->iso_frame_desc[i].length = counts * stride;
1067 		frames += counts;
1068 		urb->number_of_packets++;
1069 		subs->transfer_done += counts;
1070 		if (subs->transfer_done >= runtime->period_size) {
1071 			subs->transfer_done -= runtime->period_size;
1072 			period_elapsed = 1;
1073 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1074 				if (subs->transfer_done > 0) {
1075 					/* FIXME: fill-max mode is not
1076 					 * supported yet */
1077 					frames -= subs->transfer_done;
1078 					counts -= subs->transfer_done;
1079 					urb->iso_frame_desc[i].length =
1080 						counts * stride;
1081 					subs->transfer_done = 0;
1082 				}
1083 				i++;
1084 				if (i < ctx->packets) {
1085 					/* add a transfer delimiter */
1086 					urb->iso_frame_desc[i].offset =
1087 						frames * stride;
1088 					urb->iso_frame_desc[i].length = 0;
1089 					urb->number_of_packets++;
1090 				}
1091 				break;
1092 			}
1093 		}
1094 		if (period_elapsed &&
1095 		    !snd_usb_endpoint_implict_feedback_sink(subs->data_endpoint)) /* finish at the period boundary */
1096 			break;
1097 	}
1098 	bytes = frames * stride;
1099 	if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1100 		/* err, the transferred area goes over buffer boundary. */
1101 		unsigned int bytes1 =
1102 			runtime->buffer_size * stride - subs->hwptr_done;
1103 		memcpy(urb->transfer_buffer,
1104 		       runtime->dma_area + subs->hwptr_done, bytes1);
1105 		memcpy(urb->transfer_buffer + bytes1,
1106 		       runtime->dma_area, bytes - bytes1);
1107 	} else {
1108 		memcpy(urb->transfer_buffer,
1109 		       runtime->dma_area + subs->hwptr_done, bytes);
1110 	}
1111 	subs->hwptr_done += bytes;
1112 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1113 		subs->hwptr_done -= runtime->buffer_size * stride;
1114 
1115 	/* update delay with exact number of samples queued */
1116 	runtime->delay = subs->last_delay;
1117 	runtime->delay += frames;
1118 	subs->last_delay = runtime->delay;
1119 
1120 	/* realign last_frame_number */
1121 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1122 	subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1123 
1124 	spin_unlock_irqrestore(&subs->lock, flags);
1125 	urb->transfer_buffer_length = bytes;
1126 	if (period_elapsed)
1127 		snd_pcm_period_elapsed(subs->pcm_substream);
1128 }
1129 
1130 /*
1131  * process after playback data complete
1132  * - decrease the delay count again
1133  */
1134 static void retire_playback_urb(struct snd_usb_substream *subs,
1135 			       struct urb *urb)
1136 {
1137 	unsigned long flags;
1138 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1139 	int stride = runtime->frame_bits >> 3;
1140 	int processed = urb->transfer_buffer_length / stride;
1141 	int est_delay;
1142 
1143 	spin_lock_irqsave(&subs->lock, flags);
1144 	est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1145 	/* update delay with exact number of samples played */
1146 	if (processed > subs->last_delay)
1147 		subs->last_delay = 0;
1148 	else
1149 		subs->last_delay -= processed;
1150 	runtime->delay = subs->last_delay;
1151 
1152 	/*
1153 	 * Report when delay estimate is off by more than 2ms.
1154 	 * The error should be lower than 2ms since the estimate relies
1155 	 * on two reads of a counter updated every ms.
1156 	 */
1157 	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1158 		snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
1159 			est_delay, subs->last_delay);
1160 
1161 	spin_unlock_irqrestore(&subs->lock, flags);
1162 }
1163 
1164 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1165 {
1166 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1167 }
1168 
1169 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1170 {
1171 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1172 }
1173 
1174 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1175 {
1176 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1177 }
1178 
1179 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1180 {
1181 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1182 }
1183 
1184 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1185 					      int cmd)
1186 {
1187 	struct snd_usb_substream *subs = substream->runtime->private_data;
1188 
1189 	switch (cmd) {
1190 	case SNDRV_PCM_TRIGGER_START:
1191 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1192 		subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1193 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1194 		subs->running = 1;
1195 		return 0;
1196 	case SNDRV_PCM_TRIGGER_STOP:
1197 		stop_endpoints(subs, 0, 0, 0);
1198 		subs->running = 0;
1199 		return 0;
1200 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1201 		subs->data_endpoint->prepare_data_urb = NULL;
1202 		subs->data_endpoint->retire_data_urb = NULL;
1203 		subs->running = 0;
1204 		return 0;
1205 	}
1206 
1207 	return -EINVAL;
1208 }
1209 
1210 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1211 					     int cmd)
1212 {
1213 	int err;
1214 	struct snd_usb_substream *subs = substream->runtime->private_data;
1215 
1216 	switch (cmd) {
1217 	case SNDRV_PCM_TRIGGER_START:
1218 		err = start_endpoints(subs, 0);
1219 		if (err < 0)
1220 			return err;
1221 
1222 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1223 		subs->running = 1;
1224 		return 0;
1225 	case SNDRV_PCM_TRIGGER_STOP:
1226 		stop_endpoints(subs, 0, 0, 0);
1227 		subs->running = 0;
1228 		return 0;
1229 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1230 		subs->data_endpoint->retire_data_urb = NULL;
1231 		subs->running = 0;
1232 		return 0;
1233 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1234 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1235 		subs->running = 1;
1236 		return 0;
1237 	}
1238 
1239 	return -EINVAL;
1240 }
1241 
1242 static struct snd_pcm_ops snd_usb_playback_ops = {
1243 	.open =		snd_usb_playback_open,
1244 	.close =	snd_usb_playback_close,
1245 	.ioctl =	snd_pcm_lib_ioctl,
1246 	.hw_params =	snd_usb_hw_params,
1247 	.hw_free =	snd_usb_hw_free,
1248 	.prepare =	snd_usb_pcm_prepare,
1249 	.trigger =	snd_usb_substream_playback_trigger,
1250 	.pointer =	snd_usb_pcm_pointer,
1251 	.page =		snd_pcm_lib_get_vmalloc_page,
1252 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1253 };
1254 
1255 static struct snd_pcm_ops snd_usb_capture_ops = {
1256 	.open =		snd_usb_capture_open,
1257 	.close =	snd_usb_capture_close,
1258 	.ioctl =	snd_pcm_lib_ioctl,
1259 	.hw_params =	snd_usb_hw_params,
1260 	.hw_free =	snd_usb_hw_free,
1261 	.prepare =	snd_usb_pcm_prepare,
1262 	.trigger =	snd_usb_substream_capture_trigger,
1263 	.pointer =	snd_usb_pcm_pointer,
1264 	.page =		snd_pcm_lib_get_vmalloc_page,
1265 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1266 };
1267 
1268 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1269 {
1270 	snd_pcm_set_ops(pcm, stream,
1271 			stream == SNDRV_PCM_STREAM_PLAYBACK ?
1272 			&snd_usb_playback_ops : &snd_usb_capture_ops);
1273 }
1274