xref: /openbmc/linux/sound/usb/pcm.c (revision 84764a41)
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)
86 {
87 	struct list_head *p;
88 	struct audioformat *found = NULL;
89 	int cur_attr = 0, attr;
90 
91 	list_for_each(p, &subs->fmt_list) {
92 		struct audioformat *fp;
93 		fp = list_entry(p, struct audioformat, list);
94 		if (!(fp->formats & (1uLL << subs->pcm_format)))
95 			continue;
96 		if (fp->channels != subs->channels)
97 			continue;
98 		if (subs->cur_rate < fp->rate_min ||
99 		    subs->cur_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] == subs->cur_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  * configure endpoint params
440  *
441  * called  during initial setup and upon resume
442  */
443 static int configure_endpoint(struct snd_usb_substream *subs)
444 {
445 	int ret;
446 
447 	mutex_lock(&subs->stream->chip->shutdown_mutex);
448 	/* format changed */
449 	stop_endpoints(subs, 0, 0, 0);
450 	ret = snd_usb_endpoint_set_params(subs->data_endpoint,
451 					  subs->pcm_format,
452 					  subs->channels,
453 					  subs->period_bytes,
454 					  subs->cur_rate,
455 					  subs->cur_audiofmt,
456 					  subs->sync_endpoint);
457 	if (ret < 0)
458 		goto unlock;
459 
460 	if (subs->sync_endpoint)
461 		ret = snd_usb_endpoint_set_params(subs->data_endpoint,
462 						  subs->pcm_format,
463 						  subs->channels,
464 						  subs->period_bytes,
465 						  subs->cur_rate,
466 						  subs->cur_audiofmt,
467 						  NULL);
468 
469 unlock:
470 	mutex_unlock(&subs->stream->chip->shutdown_mutex);
471 	return ret;
472 }
473 
474 /*
475  * hw_params callback
476  *
477  * allocate a buffer and set the given audio format.
478  *
479  * so far we use a physically linear buffer although packetize transfer
480  * doesn't need a continuous area.
481  * if sg buffer is supported on the later version of alsa, we'll follow
482  * that.
483  */
484 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
485 			     struct snd_pcm_hw_params *hw_params)
486 {
487 	struct snd_usb_substream *subs = substream->runtime->private_data;
488 	struct audioformat *fmt;
489 	int ret;
490 
491 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
492 					       params_buffer_bytes(hw_params));
493 	if (ret < 0)
494 		return ret;
495 
496 	subs->pcm_format = params_format(hw_params);
497 	subs->period_bytes = params_period_bytes(hw_params);
498 	subs->channels = params_channels(hw_params);
499 	subs->cur_rate = params_rate(hw_params);
500 
501 	fmt = find_format(subs);
502 	if (!fmt) {
503 		snd_printd(KERN_DEBUG "cannot set format: format = %#x, rate = %d, channels = %d\n",
504 			   subs->pcm_format, subs->cur_rate, subs->channels);
505 		return -EINVAL;
506 	}
507 
508 	if ((ret = set_format(subs, fmt)) < 0)
509 		return ret;
510 
511 	subs->interface = fmt->iface;
512 	subs->altset_idx = fmt->altset_idx;
513 	subs->need_setup_ep = true;
514 
515 	return 0;
516 }
517 
518 /*
519  * hw_free callback
520  *
521  * reset the audio format and release the buffer
522  */
523 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
524 {
525 	struct snd_usb_substream *subs = substream->runtime->private_data;
526 
527 	subs->cur_audiofmt = NULL;
528 	subs->cur_rate = 0;
529 	subs->period_bytes = 0;
530 	mutex_lock(&subs->stream->chip->shutdown_mutex);
531 	stop_endpoints(subs, 0, 1, 1);
532 	deactivate_endpoints(subs);
533 	mutex_unlock(&subs->stream->chip->shutdown_mutex);
534 	return snd_pcm_lib_free_vmalloc_buffer(substream);
535 }
536 
537 /*
538  * prepare callback
539  *
540  * only a few subtle things...
541  */
542 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
543 {
544 	struct snd_pcm_runtime *runtime = substream->runtime;
545 	struct snd_usb_substream *subs = runtime->private_data;
546 	struct usb_host_interface *alts;
547 	struct usb_interface *iface;
548 	int ret;
549 
550 	if (! subs->cur_audiofmt) {
551 		snd_printk(KERN_ERR "usbaudio: no format is specified!\n");
552 		return -ENXIO;
553 	}
554 
555 	if (snd_BUG_ON(!subs->data_endpoint))
556 		return -EIO;
557 
558 	ret = set_format(subs, subs->cur_audiofmt);
559 	if (ret < 0)
560 		return ret;
561 
562 	iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
563 	alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
564 	ret = snd_usb_init_sample_rate(subs->stream->chip,
565 				       subs->cur_audiofmt->iface,
566 				       alts,
567 				       subs->cur_audiofmt,
568 				       subs->cur_rate);
569 	if (ret < 0)
570 		return ret;
571 
572 	if (subs->need_setup_ep) {
573 		ret = configure_endpoint(subs);
574 		if (ret < 0)
575 			return ret;
576 		subs->need_setup_ep = false;
577 	}
578 
579 	/* some unit conversions in runtime */
580 	subs->data_endpoint->maxframesize =
581 		bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
582 	subs->data_endpoint->curframesize =
583 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
584 
585 	/* reset the pointer */
586 	subs->hwptr_done = 0;
587 	subs->transfer_done = 0;
588 	subs->last_delay = 0;
589 	subs->last_frame_number = 0;
590 	runtime->delay = 0;
591 
592 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
593 	 * updates for all URBs would happen at the same time when starting */
594 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
595 		return start_endpoints(subs, 1);
596 
597 	return 0;
598 }
599 
600 static struct snd_pcm_hardware snd_usb_hardware =
601 {
602 	.info =			SNDRV_PCM_INFO_MMAP |
603 				SNDRV_PCM_INFO_MMAP_VALID |
604 				SNDRV_PCM_INFO_BATCH |
605 				SNDRV_PCM_INFO_INTERLEAVED |
606 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
607 				SNDRV_PCM_INFO_PAUSE,
608 	.buffer_bytes_max =	1024 * 1024,
609 	.period_bytes_min =	64,
610 	.period_bytes_max =	512 * 1024,
611 	.periods_min =		2,
612 	.periods_max =		1024,
613 };
614 
615 static int hw_check_valid_format(struct snd_usb_substream *subs,
616 				 struct snd_pcm_hw_params *params,
617 				 struct audioformat *fp)
618 {
619 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
620 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
621 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
622 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
623 	struct snd_mask check_fmts;
624 	unsigned int ptime;
625 
626 	/* check the format */
627 	snd_mask_none(&check_fmts);
628 	check_fmts.bits[0] = (u32)fp->formats;
629 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
630 	snd_mask_intersect(&check_fmts, fmts);
631 	if (snd_mask_empty(&check_fmts)) {
632 		hwc_debug("   > check: no supported format %d\n", fp->format);
633 		return 0;
634 	}
635 	/* check the channels */
636 	if (fp->channels < ct->min || fp->channels > ct->max) {
637 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
638 		return 0;
639 	}
640 	/* check the rate is within the range */
641 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
642 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
643 		return 0;
644 	}
645 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
646 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
647 		return 0;
648 	}
649 	/* check whether the period time is >= the data packet interval */
650 	if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL) {
651 		ptime = 125 * (1 << fp->datainterval);
652 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
653 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
654 			return 0;
655 		}
656 	}
657 	return 1;
658 }
659 
660 static int hw_rule_rate(struct snd_pcm_hw_params *params,
661 			struct snd_pcm_hw_rule *rule)
662 {
663 	struct snd_usb_substream *subs = rule->private;
664 	struct list_head *p;
665 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
666 	unsigned int rmin, rmax;
667 	int changed;
668 
669 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
670 	changed = 0;
671 	rmin = rmax = 0;
672 	list_for_each(p, &subs->fmt_list) {
673 		struct audioformat *fp;
674 		fp = list_entry(p, struct audioformat, list);
675 		if (!hw_check_valid_format(subs, params, fp))
676 			continue;
677 		if (changed++) {
678 			if (rmin > fp->rate_min)
679 				rmin = fp->rate_min;
680 			if (rmax < fp->rate_max)
681 				rmax = fp->rate_max;
682 		} else {
683 			rmin = fp->rate_min;
684 			rmax = fp->rate_max;
685 		}
686 	}
687 
688 	if (!changed) {
689 		hwc_debug("  --> get empty\n");
690 		it->empty = 1;
691 		return -EINVAL;
692 	}
693 
694 	changed = 0;
695 	if (it->min < rmin) {
696 		it->min = rmin;
697 		it->openmin = 0;
698 		changed = 1;
699 	}
700 	if (it->max > rmax) {
701 		it->max = rmax;
702 		it->openmax = 0;
703 		changed = 1;
704 	}
705 	if (snd_interval_checkempty(it)) {
706 		it->empty = 1;
707 		return -EINVAL;
708 	}
709 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
710 	return changed;
711 }
712 
713 
714 static int hw_rule_channels(struct snd_pcm_hw_params *params,
715 			    struct snd_pcm_hw_rule *rule)
716 {
717 	struct snd_usb_substream *subs = rule->private;
718 	struct list_head *p;
719 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
720 	unsigned int rmin, rmax;
721 	int changed;
722 
723 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
724 	changed = 0;
725 	rmin = rmax = 0;
726 	list_for_each(p, &subs->fmt_list) {
727 		struct audioformat *fp;
728 		fp = list_entry(p, struct audioformat, list);
729 		if (!hw_check_valid_format(subs, params, fp))
730 			continue;
731 		if (changed++) {
732 			if (rmin > fp->channels)
733 				rmin = fp->channels;
734 			if (rmax < fp->channels)
735 				rmax = fp->channels;
736 		} else {
737 			rmin = fp->channels;
738 			rmax = fp->channels;
739 		}
740 	}
741 
742 	if (!changed) {
743 		hwc_debug("  --> get empty\n");
744 		it->empty = 1;
745 		return -EINVAL;
746 	}
747 
748 	changed = 0;
749 	if (it->min < rmin) {
750 		it->min = rmin;
751 		it->openmin = 0;
752 		changed = 1;
753 	}
754 	if (it->max > rmax) {
755 		it->max = rmax;
756 		it->openmax = 0;
757 		changed = 1;
758 	}
759 	if (snd_interval_checkempty(it)) {
760 		it->empty = 1;
761 		return -EINVAL;
762 	}
763 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
764 	return changed;
765 }
766 
767 static int hw_rule_format(struct snd_pcm_hw_params *params,
768 			  struct snd_pcm_hw_rule *rule)
769 {
770 	struct snd_usb_substream *subs = rule->private;
771 	struct list_head *p;
772 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
773 	u64 fbits;
774 	u32 oldbits[2];
775 	int changed;
776 
777 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
778 	fbits = 0;
779 	list_for_each(p, &subs->fmt_list) {
780 		struct audioformat *fp;
781 		fp = list_entry(p, struct audioformat, list);
782 		if (!hw_check_valid_format(subs, params, fp))
783 			continue;
784 		fbits |= fp->formats;
785 	}
786 
787 	oldbits[0] = fmt->bits[0];
788 	oldbits[1] = fmt->bits[1];
789 	fmt->bits[0] &= (u32)fbits;
790 	fmt->bits[1] &= (u32)(fbits >> 32);
791 	if (!fmt->bits[0] && !fmt->bits[1]) {
792 		hwc_debug("  --> get empty\n");
793 		return -EINVAL;
794 	}
795 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
796 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
797 	return changed;
798 }
799 
800 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
801 			       struct snd_pcm_hw_rule *rule)
802 {
803 	struct snd_usb_substream *subs = rule->private;
804 	struct audioformat *fp;
805 	struct snd_interval *it;
806 	unsigned char min_datainterval;
807 	unsigned int pmin;
808 	int changed;
809 
810 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
811 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
812 	min_datainterval = 0xff;
813 	list_for_each_entry(fp, &subs->fmt_list, list) {
814 		if (!hw_check_valid_format(subs, params, fp))
815 			continue;
816 		min_datainterval = min(min_datainterval, fp->datainterval);
817 	}
818 	if (min_datainterval == 0xff) {
819 		hwc_debug("  --> get empty\n");
820 		it->empty = 1;
821 		return -EINVAL;
822 	}
823 	pmin = 125 * (1 << min_datainterval);
824 	changed = 0;
825 	if (it->min < pmin) {
826 		it->min = pmin;
827 		it->openmin = 0;
828 		changed = 1;
829 	}
830 	if (snd_interval_checkempty(it)) {
831 		it->empty = 1;
832 		return -EINVAL;
833 	}
834 	hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
835 	return changed;
836 }
837 
838 /*
839  *  If the device supports unusual bit rates, does the request meet these?
840  */
841 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
842 				  struct snd_usb_substream *subs)
843 {
844 	struct audioformat *fp;
845 	int *rate_list;
846 	int count = 0, needs_knot = 0;
847 	int err;
848 
849 	kfree(subs->rate_list.list);
850 	subs->rate_list.list = NULL;
851 
852 	list_for_each_entry(fp, &subs->fmt_list, list) {
853 		if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
854 			return 0;
855 		count += fp->nr_rates;
856 		if (fp->rates & SNDRV_PCM_RATE_KNOT)
857 			needs_knot = 1;
858 	}
859 	if (!needs_knot)
860 		return 0;
861 
862 	subs->rate_list.list = rate_list =
863 		kmalloc(sizeof(int) * count, GFP_KERNEL);
864 	if (!subs->rate_list.list)
865 		return -ENOMEM;
866 	subs->rate_list.count = count;
867 	subs->rate_list.mask = 0;
868 	count = 0;
869 	list_for_each_entry(fp, &subs->fmt_list, list) {
870 		int i;
871 		for (i = 0; i < fp->nr_rates; i++)
872 			rate_list[count++] = fp->rate_table[i];
873 	}
874 	err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
875 					 &subs->rate_list);
876 	if (err < 0)
877 		return err;
878 
879 	return 0;
880 }
881 
882 
883 /*
884  * set up the runtime hardware information.
885  */
886 
887 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
888 {
889 	struct list_head *p;
890 	unsigned int pt, ptmin;
891 	int param_period_time_if_needed;
892 	int err;
893 
894 	runtime->hw.formats = subs->formats;
895 
896 	runtime->hw.rate_min = 0x7fffffff;
897 	runtime->hw.rate_max = 0;
898 	runtime->hw.channels_min = 256;
899 	runtime->hw.channels_max = 0;
900 	runtime->hw.rates = 0;
901 	ptmin = UINT_MAX;
902 	/* check min/max rates and channels */
903 	list_for_each(p, &subs->fmt_list) {
904 		struct audioformat *fp;
905 		fp = list_entry(p, struct audioformat, list);
906 		runtime->hw.rates |= fp->rates;
907 		if (runtime->hw.rate_min > fp->rate_min)
908 			runtime->hw.rate_min = fp->rate_min;
909 		if (runtime->hw.rate_max < fp->rate_max)
910 			runtime->hw.rate_max = fp->rate_max;
911 		if (runtime->hw.channels_min > fp->channels)
912 			runtime->hw.channels_min = fp->channels;
913 		if (runtime->hw.channels_max < fp->channels)
914 			runtime->hw.channels_max = fp->channels;
915 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
916 			/* FIXME: there might be more than one audio formats... */
917 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
918 				fp->frame_size;
919 		}
920 		pt = 125 * (1 << fp->datainterval);
921 		ptmin = min(ptmin, pt);
922 	}
923 	err = snd_usb_autoresume(subs->stream->chip);
924 	if (err < 0)
925 		return err;
926 
927 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
928 	if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
929 		/* full speed devices have fixed data packet interval */
930 		ptmin = 1000;
931 	if (ptmin == 1000)
932 		/* if period time doesn't go below 1 ms, no rules needed */
933 		param_period_time_if_needed = -1;
934 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
935 				     ptmin, UINT_MAX);
936 
937 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
938 				       hw_rule_rate, subs,
939 				       SNDRV_PCM_HW_PARAM_FORMAT,
940 				       SNDRV_PCM_HW_PARAM_CHANNELS,
941 				       param_period_time_if_needed,
942 				       -1)) < 0)
943 		goto rep_err;
944 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
945 				       hw_rule_channels, subs,
946 				       SNDRV_PCM_HW_PARAM_FORMAT,
947 				       SNDRV_PCM_HW_PARAM_RATE,
948 				       param_period_time_if_needed,
949 				       -1)) < 0)
950 		goto rep_err;
951 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
952 				       hw_rule_format, subs,
953 				       SNDRV_PCM_HW_PARAM_RATE,
954 				       SNDRV_PCM_HW_PARAM_CHANNELS,
955 				       param_period_time_if_needed,
956 				       -1)) < 0)
957 		goto rep_err;
958 	if (param_period_time_if_needed >= 0) {
959 		err = snd_pcm_hw_rule_add(runtime, 0,
960 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
961 					  hw_rule_period_time, subs,
962 					  SNDRV_PCM_HW_PARAM_FORMAT,
963 					  SNDRV_PCM_HW_PARAM_CHANNELS,
964 					  SNDRV_PCM_HW_PARAM_RATE,
965 					  -1);
966 		if (err < 0)
967 			goto rep_err;
968 	}
969 	if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
970 		goto rep_err;
971 	return 0;
972 
973 rep_err:
974 	snd_usb_autosuspend(subs->stream->chip);
975 	return err;
976 }
977 
978 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
979 {
980 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
981 	struct snd_pcm_runtime *runtime = substream->runtime;
982 	struct snd_usb_substream *subs = &as->substream[direction];
983 
984 	subs->interface = -1;
985 	subs->altset_idx = 0;
986 	runtime->hw = snd_usb_hardware;
987 	runtime->private_data = subs;
988 	subs->pcm_substream = substream;
989 	/* runtime PM is also done there */
990 	return setup_hw_info(runtime, subs);
991 }
992 
993 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
994 {
995 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
996 	struct snd_usb_substream *subs = &as->substream[direction];
997 
998 	stop_endpoints(subs, 0, 0, 0);
999 
1000 	if (!as->chip->shutdown && subs->interface >= 0) {
1001 		usb_set_interface(subs->dev, subs->interface, 0);
1002 		subs->interface = -1;
1003 	}
1004 
1005 	subs->pcm_substream = NULL;
1006 	snd_usb_autosuspend(subs->stream->chip);
1007 
1008 	return 0;
1009 }
1010 
1011 /* Since a URB can handle only a single linear buffer, we must use double
1012  * buffering when the data to be transferred overflows the buffer boundary.
1013  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1014  * for all URBs.
1015  */
1016 static void retire_capture_urb(struct snd_usb_substream *subs,
1017 			       struct urb *urb)
1018 {
1019 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1020 	unsigned int stride, frames, bytes, oldptr;
1021 	int i, period_elapsed = 0;
1022 	unsigned long flags;
1023 	unsigned char *cp;
1024 
1025 	stride = runtime->frame_bits >> 3;
1026 
1027 	for (i = 0; i < urb->number_of_packets; i++) {
1028 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
1029 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1030 			snd_printdd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
1031 			// continue;
1032 		}
1033 		bytes = urb->iso_frame_desc[i].actual_length;
1034 		frames = bytes / stride;
1035 		if (!subs->txfr_quirk)
1036 			bytes = frames * stride;
1037 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1038 #ifdef CONFIG_SND_DEBUG_VERBOSE
1039 			int oldbytes = bytes;
1040 #endif
1041 			bytes = frames * stride;
1042 			snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
1043 							oldbytes, bytes);
1044 		}
1045 		/* update the current pointer */
1046 		spin_lock_irqsave(&subs->lock, flags);
1047 		oldptr = subs->hwptr_done;
1048 		subs->hwptr_done += bytes;
1049 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1050 			subs->hwptr_done -= runtime->buffer_size * stride;
1051 		frames = (bytes + (oldptr % stride)) / stride;
1052 		subs->transfer_done += frames;
1053 		if (subs->transfer_done >= runtime->period_size) {
1054 			subs->transfer_done -= runtime->period_size;
1055 			period_elapsed = 1;
1056 		}
1057 		spin_unlock_irqrestore(&subs->lock, flags);
1058 		/* copy a data chunk */
1059 		if (oldptr + bytes > runtime->buffer_size * stride) {
1060 			unsigned int bytes1 =
1061 					runtime->buffer_size * stride - oldptr;
1062 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1063 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1064 		} else {
1065 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1066 		}
1067 	}
1068 
1069 	if (period_elapsed)
1070 		snd_pcm_period_elapsed(subs->pcm_substream);
1071 }
1072 
1073 static void prepare_playback_urb(struct snd_usb_substream *subs,
1074 				 struct urb *urb)
1075 {
1076 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1077 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1078 	struct snd_urb_ctx *ctx = urb->context;
1079 	unsigned int counts, frames, bytes;
1080 	int i, stride, period_elapsed = 0;
1081 	unsigned long flags;
1082 
1083 	stride = runtime->frame_bits >> 3;
1084 
1085 	frames = 0;
1086 	urb->number_of_packets = 0;
1087 	spin_lock_irqsave(&subs->lock, flags);
1088 	for (i = 0; i < ctx->packets; i++) {
1089 		if (ctx->packet_size[i])
1090 			counts = ctx->packet_size[i];
1091 		else
1092 			counts = snd_usb_endpoint_next_packet_size(ep);
1093 
1094 		/* set up descriptor */
1095 		urb->iso_frame_desc[i].offset = frames * stride;
1096 		urb->iso_frame_desc[i].length = counts * stride;
1097 		frames += counts;
1098 		urb->number_of_packets++;
1099 		subs->transfer_done += counts;
1100 		if (subs->transfer_done >= runtime->period_size) {
1101 			subs->transfer_done -= runtime->period_size;
1102 			period_elapsed = 1;
1103 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1104 				if (subs->transfer_done > 0) {
1105 					/* FIXME: fill-max mode is not
1106 					 * supported yet */
1107 					frames -= subs->transfer_done;
1108 					counts -= subs->transfer_done;
1109 					urb->iso_frame_desc[i].length =
1110 						counts * stride;
1111 					subs->transfer_done = 0;
1112 				}
1113 				i++;
1114 				if (i < ctx->packets) {
1115 					/* add a transfer delimiter */
1116 					urb->iso_frame_desc[i].offset =
1117 						frames * stride;
1118 					urb->iso_frame_desc[i].length = 0;
1119 					urb->number_of_packets++;
1120 				}
1121 				break;
1122 			}
1123 		}
1124 		if (period_elapsed &&
1125 		    !snd_usb_endpoint_implict_feedback_sink(subs->data_endpoint)) /* finish at the period boundary */
1126 			break;
1127 	}
1128 	bytes = frames * stride;
1129 	if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1130 		/* err, the transferred area goes over buffer boundary. */
1131 		unsigned int bytes1 =
1132 			runtime->buffer_size * stride - subs->hwptr_done;
1133 		memcpy(urb->transfer_buffer,
1134 		       runtime->dma_area + subs->hwptr_done, bytes1);
1135 		memcpy(urb->transfer_buffer + bytes1,
1136 		       runtime->dma_area, bytes - bytes1);
1137 	} else {
1138 		memcpy(urb->transfer_buffer,
1139 		       runtime->dma_area + subs->hwptr_done, bytes);
1140 	}
1141 	subs->hwptr_done += bytes;
1142 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1143 		subs->hwptr_done -= runtime->buffer_size * stride;
1144 
1145 	/* update delay with exact number of samples queued */
1146 	runtime->delay = subs->last_delay;
1147 	runtime->delay += frames;
1148 	subs->last_delay = runtime->delay;
1149 
1150 	/* realign last_frame_number */
1151 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1152 	subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1153 
1154 	spin_unlock_irqrestore(&subs->lock, flags);
1155 	urb->transfer_buffer_length = bytes;
1156 	if (period_elapsed)
1157 		snd_pcm_period_elapsed(subs->pcm_substream);
1158 }
1159 
1160 /*
1161  * process after playback data complete
1162  * - decrease the delay count again
1163  */
1164 static void retire_playback_urb(struct snd_usb_substream *subs,
1165 			       struct urb *urb)
1166 {
1167 	unsigned long flags;
1168 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1169 	int stride = runtime->frame_bits >> 3;
1170 	int processed = urb->transfer_buffer_length / stride;
1171 	int est_delay;
1172 
1173 	/* ignore the delay accounting when procssed=0 is given, i.e.
1174 	 * silent payloads are procssed before handling the actual data
1175 	 */
1176 	if (!processed)
1177 		return;
1178 
1179 	spin_lock_irqsave(&subs->lock, flags);
1180 	est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1181 	/* update delay with exact number of samples played */
1182 	if (processed > subs->last_delay)
1183 		subs->last_delay = 0;
1184 	else
1185 		subs->last_delay -= processed;
1186 	runtime->delay = subs->last_delay;
1187 
1188 	/*
1189 	 * Report when delay estimate is off by more than 2ms.
1190 	 * The error should be lower than 2ms since the estimate relies
1191 	 * on two reads of a counter updated every ms.
1192 	 */
1193 	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1194 		snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
1195 			est_delay, subs->last_delay);
1196 
1197 	spin_unlock_irqrestore(&subs->lock, flags);
1198 }
1199 
1200 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1201 {
1202 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1203 }
1204 
1205 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1206 {
1207 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1208 }
1209 
1210 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1211 {
1212 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1213 }
1214 
1215 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1216 {
1217 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1218 }
1219 
1220 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1221 					      int cmd)
1222 {
1223 	struct snd_usb_substream *subs = substream->runtime->private_data;
1224 
1225 	switch (cmd) {
1226 	case SNDRV_PCM_TRIGGER_START:
1227 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1228 		subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1229 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1230 		subs->running = 1;
1231 		return 0;
1232 	case SNDRV_PCM_TRIGGER_STOP:
1233 		stop_endpoints(subs, 0, 0, 0);
1234 		subs->running = 0;
1235 		return 0;
1236 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1237 		subs->data_endpoint->prepare_data_urb = NULL;
1238 		subs->data_endpoint->retire_data_urb = NULL;
1239 		subs->running = 0;
1240 		return 0;
1241 	}
1242 
1243 	return -EINVAL;
1244 }
1245 
1246 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1247 					     int cmd)
1248 {
1249 	int err;
1250 	struct snd_usb_substream *subs = substream->runtime->private_data;
1251 
1252 	switch (cmd) {
1253 	case SNDRV_PCM_TRIGGER_START:
1254 		err = start_endpoints(subs, 0);
1255 		if (err < 0)
1256 			return err;
1257 
1258 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1259 		subs->running = 1;
1260 		return 0;
1261 	case SNDRV_PCM_TRIGGER_STOP:
1262 		stop_endpoints(subs, 0, 0, 0);
1263 		subs->running = 0;
1264 		return 0;
1265 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1266 		subs->data_endpoint->retire_data_urb = NULL;
1267 		subs->running = 0;
1268 		return 0;
1269 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1270 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1271 		subs->running = 1;
1272 		return 0;
1273 	}
1274 
1275 	return -EINVAL;
1276 }
1277 
1278 static struct snd_pcm_ops snd_usb_playback_ops = {
1279 	.open =		snd_usb_playback_open,
1280 	.close =	snd_usb_playback_close,
1281 	.ioctl =	snd_pcm_lib_ioctl,
1282 	.hw_params =	snd_usb_hw_params,
1283 	.hw_free =	snd_usb_hw_free,
1284 	.prepare =	snd_usb_pcm_prepare,
1285 	.trigger =	snd_usb_substream_playback_trigger,
1286 	.pointer =	snd_usb_pcm_pointer,
1287 	.page =		snd_pcm_lib_get_vmalloc_page,
1288 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1289 };
1290 
1291 static struct snd_pcm_ops snd_usb_capture_ops = {
1292 	.open =		snd_usb_capture_open,
1293 	.close =	snd_usb_capture_close,
1294 	.ioctl =	snd_pcm_lib_ioctl,
1295 	.hw_params =	snd_usb_hw_params,
1296 	.hw_free =	snd_usb_hw_free,
1297 	.prepare =	snd_usb_pcm_prepare,
1298 	.trigger =	snd_usb_substream_capture_trigger,
1299 	.pointer =	snd_usb_pcm_pointer,
1300 	.page =		snd_pcm_lib_get_vmalloc_page,
1301 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1302 };
1303 
1304 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1305 {
1306 	snd_pcm_set_ops(pcm, stream,
1307 			stream == SNDRV_PCM_STREAM_PLAYBACK ?
1308 			&snd_usb_playback_ops : &snd_usb_capture_ops);
1309 }
1310