xref: /linux/sound/usb/pcm.c (revision cf02820041668b14cbfa0fbd2bab45ac79bd6174)
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 	if (subs->stream->chip->shutdown)
75 		return SNDRV_PCM_POS_XRUN;
76 	spin_lock(&subs->lock);
77 	hwptr_done = subs->hwptr_done;
78 	substream->runtime->delay = snd_usb_pcm_delay(subs,
79 						substream->runtime->rate);
80 	spin_unlock(&subs->lock);
81 	return hwptr_done / (substream->runtime->frame_bits >> 3);
82 }
83 
84 /*
85  * find a matching audio format
86  */
87 static struct audioformat *find_format(struct snd_usb_substream *subs)
88 {
89 	struct list_head *p;
90 	struct audioformat *found = NULL;
91 	int cur_attr = 0, attr;
92 
93 	list_for_each(p, &subs->fmt_list) {
94 		struct audioformat *fp;
95 		fp = list_entry(p, struct audioformat, list);
96 		if (!(fp->formats & (1uLL << subs->pcm_format)))
97 			continue;
98 		if (fp->channels != subs->channels)
99 			continue;
100 		if (subs->cur_rate < fp->rate_min ||
101 		    subs->cur_rate > fp->rate_max)
102 			continue;
103 		if (! (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
104 			unsigned int i;
105 			for (i = 0; i < fp->nr_rates; i++)
106 				if (fp->rate_table[i] == subs->cur_rate)
107 					break;
108 			if (i >= fp->nr_rates)
109 				continue;
110 		}
111 		attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
112 		if (! found) {
113 			found = fp;
114 			cur_attr = attr;
115 			continue;
116 		}
117 		/* avoid async out and adaptive in if the other method
118 		 * supports the same format.
119 		 * this is a workaround for the case like
120 		 * M-audio audiophile USB.
121 		 */
122 		if (attr != cur_attr) {
123 			if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
124 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
125 			    (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
126 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE))
127 				continue;
128 			if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
129 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
130 			    (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
131 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
132 				found = fp;
133 				cur_attr = attr;
134 				continue;
135 			}
136 		}
137 		/* find the format with the largest max. packet size */
138 		if (fp->maxpacksize > found->maxpacksize) {
139 			found = fp;
140 			cur_attr = attr;
141 		}
142 	}
143 	return found;
144 }
145 
146 static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
147 			 struct usb_host_interface *alts,
148 			 struct audioformat *fmt)
149 {
150 	struct usb_device *dev = chip->dev;
151 	unsigned int ep;
152 	unsigned char data[1];
153 	int err;
154 
155 	ep = get_endpoint(alts, 0)->bEndpointAddress;
156 
157 	data[0] = 1;
158 	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
159 				   USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
160 				   UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
161 				   data, sizeof(data))) < 0) {
162 		snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH\n",
163 			   dev->devnum, iface, ep);
164 		return err;
165 	}
166 
167 	return 0;
168 }
169 
170 static int init_pitch_v2(struct snd_usb_audio *chip, int iface,
171 			 struct usb_host_interface *alts,
172 			 struct audioformat *fmt)
173 {
174 	struct usb_device *dev = chip->dev;
175 	unsigned char data[1];
176 	unsigned int ep;
177 	int err;
178 
179 	ep = get_endpoint(alts, 0)->bEndpointAddress;
180 
181 	data[0] = 1;
182 	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
183 				   USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
184 				   UAC2_EP_CS_PITCH << 8, 0,
185 				   data, sizeof(data))) < 0) {
186 		snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH (v2)\n",
187 			   dev->devnum, iface, fmt->altsetting);
188 		return err;
189 	}
190 
191 	return 0;
192 }
193 
194 /*
195  * initialize the pitch control and sample rate
196  */
197 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
198 		       struct usb_host_interface *alts,
199 		       struct audioformat *fmt)
200 {
201 	struct usb_interface_descriptor *altsd = get_iface_desc(alts);
202 
203 	/* if endpoint doesn't have pitch control, bail out */
204 	if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
205 		return 0;
206 
207 	switch (altsd->bInterfaceProtocol) {
208 	case UAC_VERSION_1:
209 	default:
210 		return init_pitch_v1(chip, iface, alts, fmt);
211 
212 	case UAC_VERSION_2:
213 		return init_pitch_v2(chip, iface, alts, fmt);
214 	}
215 }
216 
217 static int start_endpoints(struct snd_usb_substream *subs, int can_sleep)
218 {
219 	int err;
220 
221 	if (!subs->data_endpoint)
222 		return -EINVAL;
223 
224 	if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
225 		struct snd_usb_endpoint *ep = subs->data_endpoint;
226 
227 		snd_printdd(KERN_DEBUG "Starting data EP @%p\n", ep);
228 
229 		ep->data_subs = subs;
230 		err = snd_usb_endpoint_start(ep, can_sleep);
231 		if (err < 0) {
232 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
233 			return err;
234 		}
235 	}
236 
237 	if (subs->sync_endpoint &&
238 	    !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
239 		struct snd_usb_endpoint *ep = subs->sync_endpoint;
240 
241 		if (subs->data_endpoint->iface != subs->sync_endpoint->iface ||
242 		    subs->data_endpoint->alt_idx != subs->sync_endpoint->alt_idx) {
243 			err = usb_set_interface(subs->dev,
244 						subs->sync_endpoint->iface,
245 						subs->sync_endpoint->alt_idx);
246 			if (err < 0) {
247 				snd_printk(KERN_ERR
248 					   "%d:%d:%d: cannot set interface (%d)\n",
249 					   subs->dev->devnum,
250 					   subs->sync_endpoint->iface,
251 					   subs->sync_endpoint->alt_idx, err);
252 				return -EIO;
253 			}
254 		}
255 
256 		snd_printdd(KERN_DEBUG "Starting sync EP @%p\n", ep);
257 
258 		ep->sync_slave = subs->data_endpoint;
259 		err = snd_usb_endpoint_start(ep, can_sleep);
260 		if (err < 0) {
261 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
262 			return err;
263 		}
264 	}
265 
266 	return 0;
267 }
268 
269 static void stop_endpoints(struct snd_usb_substream *subs,
270 			   int force, int can_sleep, int wait)
271 {
272 	if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags))
273 		snd_usb_endpoint_stop(subs->sync_endpoint,
274 				      force, can_sleep, wait);
275 
276 	if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags))
277 		snd_usb_endpoint_stop(subs->data_endpoint,
278 				      force, can_sleep, wait);
279 }
280 
281 static int deactivate_endpoints(struct snd_usb_substream *subs)
282 {
283 	int reta, retb;
284 
285 	reta = snd_usb_endpoint_deactivate(subs->sync_endpoint);
286 	retb = snd_usb_endpoint_deactivate(subs->data_endpoint);
287 
288 	if (reta < 0)
289 		return reta;
290 
291 	if (retb < 0)
292 		return retb;
293 
294 	return 0;
295 }
296 
297 /*
298  * find a matching format and set up the interface
299  */
300 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
301 {
302 	struct usb_device *dev = subs->dev;
303 	struct usb_host_interface *alts;
304 	struct usb_interface_descriptor *altsd;
305 	struct usb_interface *iface;
306 	unsigned int ep, attr;
307 	int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
308 	int err, implicit_fb = 0;
309 
310 	iface = usb_ifnum_to_if(dev, fmt->iface);
311 	if (WARN_ON(!iface))
312 		return -EINVAL;
313 	alts = &iface->altsetting[fmt->altset_idx];
314 	altsd = get_iface_desc(alts);
315 	if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
316 		return -EINVAL;
317 
318 	if (fmt == subs->cur_audiofmt)
319 		return 0;
320 
321 	/* close the old interface */
322 	if (subs->interface >= 0 && subs->interface != fmt->iface) {
323 		err = usb_set_interface(subs->dev, subs->interface, 0);
324 		if (err < 0) {
325 			snd_printk(KERN_ERR "%d:%d:%d: return to setting 0 failed (%d)\n",
326 				dev->devnum, fmt->iface, fmt->altsetting, err);
327 			return -EIO;
328 		}
329 		subs->interface = -1;
330 		subs->altset_idx = 0;
331 	}
332 
333 	/* set interface */
334 	if (subs->interface != fmt->iface ||
335 	    subs->altset_idx != fmt->altset_idx) {
336 		err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
337 		if (err < 0) {
338 			snd_printk(KERN_ERR "%d:%d:%d: usb_set_interface failed (%d)\n",
339 				   dev->devnum, fmt->iface, fmt->altsetting, err);
340 			return -EIO;
341 		}
342 		snd_printdd(KERN_INFO "setting usb interface %d:%d\n",
343 				fmt->iface, fmt->altsetting);
344 		subs->interface = fmt->iface;
345 		subs->altset_idx = fmt->altset_idx;
346 	}
347 
348 	subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
349 						   alts, fmt->endpoint, subs->direction,
350 						   SND_USB_ENDPOINT_TYPE_DATA);
351 	if (!subs->data_endpoint)
352 		return -EINVAL;
353 
354 	/* we need a sync pipe in async OUT or adaptive IN mode */
355 	/* check the number of EP, since some devices have broken
356 	 * descriptors which fool us.  if it has only one EP,
357 	 * assume it as adaptive-out or sync-in.
358 	 */
359 	attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
360 
361 	switch (subs->stream->chip->usb_id) {
362 	case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
363 	case USB_ID(0x0763, 0x2081):
364 		if (is_playback) {
365 			implicit_fb = 1;
366 			ep = 0x81;
367 			iface = usb_ifnum_to_if(dev, 2);
368 
369 			if (!iface || iface->num_altsetting == 0)
370 				return -EINVAL;
371 
372 			alts = &iface->altsetting[1];
373 			goto add_sync_ep;
374 		}
375 	}
376 
377 	if (((is_playback && attr == USB_ENDPOINT_SYNC_ASYNC) ||
378 	     (!is_playback && attr == USB_ENDPOINT_SYNC_ADAPTIVE)) &&
379 	    altsd->bNumEndpoints >= 2) {
380 		/* check sync-pipe endpoint */
381 		/* ... and check descriptor size before accessing bSynchAddress
382 		   because there is a version of the SB Audigy 2 NX firmware lacking
383 		   the audio fields in the endpoint descriptors */
384 		if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != 0x01 ||
385 		    (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
386 		     get_endpoint(alts, 1)->bSynchAddress != 0 &&
387 		     !implicit_fb)) {
388 			snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
389 				   dev->devnum, fmt->iface, fmt->altsetting,
390 				   get_endpoint(alts, 1)->bmAttributes,
391 				   get_endpoint(alts, 1)->bLength,
392 				   get_endpoint(alts, 1)->bSynchAddress);
393 			return -EINVAL;
394 		}
395 		ep = get_endpoint(alts, 1)->bEndpointAddress;
396 		if (!implicit_fb &&
397 		    get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
398 		    (( is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
399 		     (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
400 			snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
401 				   dev->devnum, fmt->iface, fmt->altsetting,
402 				   is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
403 			return -EINVAL;
404 		}
405 
406 		implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
407 				== USB_ENDPOINT_USAGE_IMPLICIT_FB;
408 
409 add_sync_ep:
410 		subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
411 							   alts, ep, !subs->direction,
412 							   implicit_fb ?
413 								SND_USB_ENDPOINT_TYPE_DATA :
414 								SND_USB_ENDPOINT_TYPE_SYNC);
415 		if (!subs->sync_endpoint)
416 			return -EINVAL;
417 
418 		subs->data_endpoint->sync_master = subs->sync_endpoint;
419 	}
420 
421 	if ((err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt)) < 0)
422 		return err;
423 
424 	subs->cur_audiofmt = fmt;
425 
426 	snd_usb_set_format_quirk(subs, fmt);
427 
428 #if 0
429 	printk(KERN_DEBUG
430 	       "setting done: format = %d, rate = %d..%d, channels = %d\n",
431 	       fmt->format, fmt->rate_min, fmt->rate_max, fmt->channels);
432 	printk(KERN_DEBUG
433 	       "  datapipe = 0x%0x, syncpipe = 0x%0x\n",
434 	       subs->datapipe, subs->syncpipe);
435 #endif
436 
437 	return 0;
438 }
439 
440 /*
441  * configure endpoint params
442  *
443  * called  during initial setup and upon resume
444  */
445 static int configure_endpoint(struct snd_usb_substream *subs)
446 {
447 	int ret;
448 
449 	/* format changed */
450 	stop_endpoints(subs, 0, 0, 0);
451 	ret = snd_usb_endpoint_set_params(subs->data_endpoint,
452 					  subs->pcm_format,
453 					  subs->channels,
454 					  subs->period_bytes,
455 					  subs->cur_rate,
456 					  subs->cur_audiofmt,
457 					  subs->sync_endpoint);
458 	if (ret < 0)
459 		return ret;
460 
461 	if (subs->sync_endpoint)
462 		ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
463 						  subs->pcm_format,
464 						  subs->channels,
465 						  subs->period_bytes,
466 						  subs->cur_rate,
467 						  subs->cur_audiofmt,
468 						  NULL);
469 	return ret;
470 }
471 
472 /*
473  * hw_params callback
474  *
475  * allocate a buffer and set the given audio format.
476  *
477  * so far we use a physically linear buffer although packetize transfer
478  * doesn't need a continuous area.
479  * if sg buffer is supported on the later version of alsa, we'll follow
480  * that.
481  */
482 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
483 			     struct snd_pcm_hw_params *hw_params)
484 {
485 	struct snd_usb_substream *subs = substream->runtime->private_data;
486 	struct audioformat *fmt;
487 	int ret;
488 
489 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
490 					       params_buffer_bytes(hw_params));
491 	if (ret < 0)
492 		return ret;
493 
494 	subs->pcm_format = params_format(hw_params);
495 	subs->period_bytes = params_period_bytes(hw_params);
496 	subs->channels = params_channels(hw_params);
497 	subs->cur_rate = params_rate(hw_params);
498 
499 	fmt = find_format(subs);
500 	if (!fmt) {
501 		snd_printd(KERN_DEBUG "cannot set format: format = %#x, rate = %d, channels = %d\n",
502 			   subs->pcm_format, subs->cur_rate, subs->channels);
503 		return -EINVAL;
504 	}
505 
506 	down_read(&subs->stream->chip->shutdown_rwsem);
507 	if (subs->stream->chip->shutdown)
508 		ret = -ENODEV;
509 	else
510 		ret = set_format(subs, fmt);
511 	up_read(&subs->stream->chip->shutdown_rwsem);
512 	if (ret < 0)
513 		return ret;
514 
515 	subs->interface = fmt->iface;
516 	subs->altset_idx = fmt->altset_idx;
517 	subs->need_setup_ep = true;
518 
519 	return 0;
520 }
521 
522 /*
523  * hw_free callback
524  *
525  * reset the audio format and release the buffer
526  */
527 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
528 {
529 	struct snd_usb_substream *subs = substream->runtime->private_data;
530 
531 	subs->cur_audiofmt = NULL;
532 	subs->cur_rate = 0;
533 	subs->period_bytes = 0;
534 	down_read(&subs->stream->chip->shutdown_rwsem);
535 	if (!subs->stream->chip->shutdown) {
536 		stop_endpoints(subs, 0, 1, 1);
537 		deactivate_endpoints(subs);
538 	}
539 	up_read(&subs->stream->chip->shutdown_rwsem);
540 	return snd_pcm_lib_free_vmalloc_buffer(substream);
541 }
542 
543 /*
544  * prepare callback
545  *
546  * only a few subtle things...
547  */
548 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
549 {
550 	struct snd_pcm_runtime *runtime = substream->runtime;
551 	struct snd_usb_substream *subs = runtime->private_data;
552 	struct usb_host_interface *alts;
553 	struct usb_interface *iface;
554 	int ret;
555 
556 	if (! subs->cur_audiofmt) {
557 		snd_printk(KERN_ERR "usbaudio: no format is specified!\n");
558 		return -ENXIO;
559 	}
560 
561 	down_read(&subs->stream->chip->shutdown_rwsem);
562 	if (subs->stream->chip->shutdown) {
563 		ret = -ENODEV;
564 		goto unlock;
565 	}
566 	if (snd_BUG_ON(!subs->data_endpoint)) {
567 		ret = -EIO;
568 		goto unlock;
569 	}
570 
571 	snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
572 	snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
573 
574 	ret = set_format(subs, subs->cur_audiofmt);
575 	if (ret < 0)
576 		goto unlock;
577 
578 	iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
579 	alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
580 	ret = snd_usb_init_sample_rate(subs->stream->chip,
581 				       subs->cur_audiofmt->iface,
582 				       alts,
583 				       subs->cur_audiofmt,
584 				       subs->cur_rate);
585 	if (ret < 0)
586 		goto unlock;
587 
588 	if (subs->need_setup_ep) {
589 		ret = configure_endpoint(subs);
590 		if (ret < 0)
591 			goto unlock;
592 		subs->need_setup_ep = false;
593 	}
594 
595 	/* some unit conversions in runtime */
596 	subs->data_endpoint->maxframesize =
597 		bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
598 	subs->data_endpoint->curframesize =
599 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
600 
601 	/* reset the pointer */
602 	subs->hwptr_done = 0;
603 	subs->transfer_done = 0;
604 	subs->last_delay = 0;
605 	subs->last_frame_number = 0;
606 	runtime->delay = 0;
607 
608 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
609 	 * updates for all URBs would happen at the same time when starting */
610 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
611 		ret = start_endpoints(subs, 1);
612 
613  unlock:
614 	up_read(&subs->stream->chip->shutdown_rwsem);
615 	return ret;
616 }
617 
618 static struct snd_pcm_hardware snd_usb_hardware =
619 {
620 	.info =			SNDRV_PCM_INFO_MMAP |
621 				SNDRV_PCM_INFO_MMAP_VALID |
622 				SNDRV_PCM_INFO_BATCH |
623 				SNDRV_PCM_INFO_INTERLEAVED |
624 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
625 				SNDRV_PCM_INFO_PAUSE,
626 	.buffer_bytes_max =	1024 * 1024,
627 	.period_bytes_min =	64,
628 	.period_bytes_max =	512 * 1024,
629 	.periods_min =		2,
630 	.periods_max =		1024,
631 };
632 
633 static int hw_check_valid_format(struct snd_usb_substream *subs,
634 				 struct snd_pcm_hw_params *params,
635 				 struct audioformat *fp)
636 {
637 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
638 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
639 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
640 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
641 	struct snd_mask check_fmts;
642 	unsigned int ptime;
643 
644 	/* check the format */
645 	snd_mask_none(&check_fmts);
646 	check_fmts.bits[0] = (u32)fp->formats;
647 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
648 	snd_mask_intersect(&check_fmts, fmts);
649 	if (snd_mask_empty(&check_fmts)) {
650 		hwc_debug("   > check: no supported format %d\n", fp->format);
651 		return 0;
652 	}
653 	/* check the channels */
654 	if (fp->channels < ct->min || fp->channels > ct->max) {
655 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
656 		return 0;
657 	}
658 	/* check the rate is within the range */
659 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
660 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
661 		return 0;
662 	}
663 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
664 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
665 		return 0;
666 	}
667 	/* check whether the period time is >= the data packet interval */
668 	if (subs->speed != USB_SPEED_FULL) {
669 		ptime = 125 * (1 << fp->datainterval);
670 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
671 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
672 			return 0;
673 		}
674 	}
675 	return 1;
676 }
677 
678 static int hw_rule_rate(struct snd_pcm_hw_params *params,
679 			struct snd_pcm_hw_rule *rule)
680 {
681 	struct snd_usb_substream *subs = rule->private;
682 	struct list_head *p;
683 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
684 	unsigned int rmin, rmax;
685 	int changed;
686 
687 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
688 	changed = 0;
689 	rmin = rmax = 0;
690 	list_for_each(p, &subs->fmt_list) {
691 		struct audioformat *fp;
692 		fp = list_entry(p, struct audioformat, list);
693 		if (!hw_check_valid_format(subs, params, fp))
694 			continue;
695 		if (changed++) {
696 			if (rmin > fp->rate_min)
697 				rmin = fp->rate_min;
698 			if (rmax < fp->rate_max)
699 				rmax = fp->rate_max;
700 		} else {
701 			rmin = fp->rate_min;
702 			rmax = fp->rate_max;
703 		}
704 	}
705 
706 	if (!changed) {
707 		hwc_debug("  --> get empty\n");
708 		it->empty = 1;
709 		return -EINVAL;
710 	}
711 
712 	changed = 0;
713 	if (it->min < rmin) {
714 		it->min = rmin;
715 		it->openmin = 0;
716 		changed = 1;
717 	}
718 	if (it->max > rmax) {
719 		it->max = rmax;
720 		it->openmax = 0;
721 		changed = 1;
722 	}
723 	if (snd_interval_checkempty(it)) {
724 		it->empty = 1;
725 		return -EINVAL;
726 	}
727 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
728 	return changed;
729 }
730 
731 
732 static int hw_rule_channels(struct snd_pcm_hw_params *params,
733 			    struct snd_pcm_hw_rule *rule)
734 {
735 	struct snd_usb_substream *subs = rule->private;
736 	struct list_head *p;
737 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
738 	unsigned int rmin, rmax;
739 	int changed;
740 
741 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
742 	changed = 0;
743 	rmin = rmax = 0;
744 	list_for_each(p, &subs->fmt_list) {
745 		struct audioformat *fp;
746 		fp = list_entry(p, struct audioformat, list);
747 		if (!hw_check_valid_format(subs, params, fp))
748 			continue;
749 		if (changed++) {
750 			if (rmin > fp->channels)
751 				rmin = fp->channels;
752 			if (rmax < fp->channels)
753 				rmax = fp->channels;
754 		} else {
755 			rmin = fp->channels;
756 			rmax = fp->channels;
757 		}
758 	}
759 
760 	if (!changed) {
761 		hwc_debug("  --> get empty\n");
762 		it->empty = 1;
763 		return -EINVAL;
764 	}
765 
766 	changed = 0;
767 	if (it->min < rmin) {
768 		it->min = rmin;
769 		it->openmin = 0;
770 		changed = 1;
771 	}
772 	if (it->max > rmax) {
773 		it->max = rmax;
774 		it->openmax = 0;
775 		changed = 1;
776 	}
777 	if (snd_interval_checkempty(it)) {
778 		it->empty = 1;
779 		return -EINVAL;
780 	}
781 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
782 	return changed;
783 }
784 
785 static int hw_rule_format(struct snd_pcm_hw_params *params,
786 			  struct snd_pcm_hw_rule *rule)
787 {
788 	struct snd_usb_substream *subs = rule->private;
789 	struct list_head *p;
790 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
791 	u64 fbits;
792 	u32 oldbits[2];
793 	int changed;
794 
795 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
796 	fbits = 0;
797 	list_for_each(p, &subs->fmt_list) {
798 		struct audioformat *fp;
799 		fp = list_entry(p, struct audioformat, list);
800 		if (!hw_check_valid_format(subs, params, fp))
801 			continue;
802 		fbits |= fp->formats;
803 	}
804 
805 	oldbits[0] = fmt->bits[0];
806 	oldbits[1] = fmt->bits[1];
807 	fmt->bits[0] &= (u32)fbits;
808 	fmt->bits[1] &= (u32)(fbits >> 32);
809 	if (!fmt->bits[0] && !fmt->bits[1]) {
810 		hwc_debug("  --> get empty\n");
811 		return -EINVAL;
812 	}
813 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
814 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
815 	return changed;
816 }
817 
818 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
819 			       struct snd_pcm_hw_rule *rule)
820 {
821 	struct snd_usb_substream *subs = rule->private;
822 	struct audioformat *fp;
823 	struct snd_interval *it;
824 	unsigned char min_datainterval;
825 	unsigned int pmin;
826 	int changed;
827 
828 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
829 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
830 	min_datainterval = 0xff;
831 	list_for_each_entry(fp, &subs->fmt_list, list) {
832 		if (!hw_check_valid_format(subs, params, fp))
833 			continue;
834 		min_datainterval = min(min_datainterval, fp->datainterval);
835 	}
836 	if (min_datainterval == 0xff) {
837 		hwc_debug("  --> get empty\n");
838 		it->empty = 1;
839 		return -EINVAL;
840 	}
841 	pmin = 125 * (1 << min_datainterval);
842 	changed = 0;
843 	if (it->min < pmin) {
844 		it->min = pmin;
845 		it->openmin = 0;
846 		changed = 1;
847 	}
848 	if (snd_interval_checkempty(it)) {
849 		it->empty = 1;
850 		return -EINVAL;
851 	}
852 	hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
853 	return changed;
854 }
855 
856 /*
857  *  If the device supports unusual bit rates, does the request meet these?
858  */
859 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
860 				  struct snd_usb_substream *subs)
861 {
862 	struct audioformat *fp;
863 	int *rate_list;
864 	int count = 0, needs_knot = 0;
865 	int err;
866 
867 	kfree(subs->rate_list.list);
868 	subs->rate_list.list = NULL;
869 
870 	list_for_each_entry(fp, &subs->fmt_list, list) {
871 		if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
872 			return 0;
873 		count += fp->nr_rates;
874 		if (fp->rates & SNDRV_PCM_RATE_KNOT)
875 			needs_knot = 1;
876 	}
877 	if (!needs_knot)
878 		return 0;
879 
880 	subs->rate_list.list = rate_list =
881 		kmalloc(sizeof(int) * count, GFP_KERNEL);
882 	if (!subs->rate_list.list)
883 		return -ENOMEM;
884 	subs->rate_list.count = count;
885 	subs->rate_list.mask = 0;
886 	count = 0;
887 	list_for_each_entry(fp, &subs->fmt_list, list) {
888 		int i;
889 		for (i = 0; i < fp->nr_rates; i++)
890 			rate_list[count++] = fp->rate_table[i];
891 	}
892 	err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
893 					 &subs->rate_list);
894 	if (err < 0)
895 		return err;
896 
897 	return 0;
898 }
899 
900 
901 /*
902  * set up the runtime hardware information.
903  */
904 
905 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
906 {
907 	struct list_head *p;
908 	unsigned int pt, ptmin;
909 	int param_period_time_if_needed;
910 	int err;
911 
912 	runtime->hw.formats = subs->formats;
913 
914 	runtime->hw.rate_min = 0x7fffffff;
915 	runtime->hw.rate_max = 0;
916 	runtime->hw.channels_min = 256;
917 	runtime->hw.channels_max = 0;
918 	runtime->hw.rates = 0;
919 	ptmin = UINT_MAX;
920 	/* check min/max rates and channels */
921 	list_for_each(p, &subs->fmt_list) {
922 		struct audioformat *fp;
923 		fp = list_entry(p, struct audioformat, list);
924 		runtime->hw.rates |= fp->rates;
925 		if (runtime->hw.rate_min > fp->rate_min)
926 			runtime->hw.rate_min = fp->rate_min;
927 		if (runtime->hw.rate_max < fp->rate_max)
928 			runtime->hw.rate_max = fp->rate_max;
929 		if (runtime->hw.channels_min > fp->channels)
930 			runtime->hw.channels_min = fp->channels;
931 		if (runtime->hw.channels_max < fp->channels)
932 			runtime->hw.channels_max = fp->channels;
933 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
934 			/* FIXME: there might be more than one audio formats... */
935 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
936 				fp->frame_size;
937 		}
938 		pt = 125 * (1 << fp->datainterval);
939 		ptmin = min(ptmin, pt);
940 	}
941 	err = snd_usb_autoresume(subs->stream->chip);
942 	if (err < 0)
943 		return err;
944 
945 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
946 	if (subs->speed == USB_SPEED_FULL)
947 		/* full speed devices have fixed data packet interval */
948 		ptmin = 1000;
949 	if (ptmin == 1000)
950 		/* if period time doesn't go below 1 ms, no rules needed */
951 		param_period_time_if_needed = -1;
952 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
953 				     ptmin, UINT_MAX);
954 
955 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
956 				       hw_rule_rate, subs,
957 				       SNDRV_PCM_HW_PARAM_FORMAT,
958 				       SNDRV_PCM_HW_PARAM_CHANNELS,
959 				       param_period_time_if_needed,
960 				       -1)) < 0)
961 		goto rep_err;
962 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
963 				       hw_rule_channels, subs,
964 				       SNDRV_PCM_HW_PARAM_FORMAT,
965 				       SNDRV_PCM_HW_PARAM_RATE,
966 				       param_period_time_if_needed,
967 				       -1)) < 0)
968 		goto rep_err;
969 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
970 				       hw_rule_format, subs,
971 				       SNDRV_PCM_HW_PARAM_RATE,
972 				       SNDRV_PCM_HW_PARAM_CHANNELS,
973 				       param_period_time_if_needed,
974 				       -1)) < 0)
975 		goto rep_err;
976 	if (param_period_time_if_needed >= 0) {
977 		err = snd_pcm_hw_rule_add(runtime, 0,
978 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
979 					  hw_rule_period_time, subs,
980 					  SNDRV_PCM_HW_PARAM_FORMAT,
981 					  SNDRV_PCM_HW_PARAM_CHANNELS,
982 					  SNDRV_PCM_HW_PARAM_RATE,
983 					  -1);
984 		if (err < 0)
985 			goto rep_err;
986 	}
987 	if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
988 		goto rep_err;
989 	return 0;
990 
991 rep_err:
992 	snd_usb_autosuspend(subs->stream->chip);
993 	return err;
994 }
995 
996 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
997 {
998 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
999 	struct snd_pcm_runtime *runtime = substream->runtime;
1000 	struct snd_usb_substream *subs = &as->substream[direction];
1001 
1002 	subs->interface = -1;
1003 	subs->altset_idx = 0;
1004 	runtime->hw = snd_usb_hardware;
1005 	runtime->private_data = subs;
1006 	subs->pcm_substream = substream;
1007 	/* runtime PM is also done there */
1008 	return setup_hw_info(runtime, subs);
1009 }
1010 
1011 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
1012 {
1013 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1014 	struct snd_usb_substream *subs = &as->substream[direction];
1015 
1016 	stop_endpoints(subs, 0, 0, 0);
1017 
1018 	if (!as->chip->shutdown && subs->interface >= 0) {
1019 		usb_set_interface(subs->dev, subs->interface, 0);
1020 		subs->interface = -1;
1021 	}
1022 
1023 	subs->pcm_substream = NULL;
1024 	snd_usb_autosuspend(subs->stream->chip);
1025 
1026 	return 0;
1027 }
1028 
1029 /* Since a URB can handle only a single linear buffer, we must use double
1030  * buffering when the data to be transferred overflows the buffer boundary.
1031  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1032  * for all URBs.
1033  */
1034 static void retire_capture_urb(struct snd_usb_substream *subs,
1035 			       struct urb *urb)
1036 {
1037 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1038 	unsigned int stride, frames, bytes, oldptr;
1039 	int i, period_elapsed = 0;
1040 	unsigned long flags;
1041 	unsigned char *cp;
1042 
1043 	stride = runtime->frame_bits >> 3;
1044 
1045 	for (i = 0; i < urb->number_of_packets; i++) {
1046 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
1047 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1048 			snd_printdd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
1049 			// continue;
1050 		}
1051 		bytes = urb->iso_frame_desc[i].actual_length;
1052 		frames = bytes / stride;
1053 		if (!subs->txfr_quirk)
1054 			bytes = frames * stride;
1055 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1056 #ifdef CONFIG_SND_DEBUG_VERBOSE
1057 			int oldbytes = bytes;
1058 #endif
1059 			bytes = frames * stride;
1060 			snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
1061 							oldbytes, bytes);
1062 		}
1063 		/* update the current pointer */
1064 		spin_lock_irqsave(&subs->lock, flags);
1065 		oldptr = subs->hwptr_done;
1066 		subs->hwptr_done += bytes;
1067 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1068 			subs->hwptr_done -= runtime->buffer_size * stride;
1069 		frames = (bytes + (oldptr % stride)) / stride;
1070 		subs->transfer_done += frames;
1071 		if (subs->transfer_done >= runtime->period_size) {
1072 			subs->transfer_done -= runtime->period_size;
1073 			period_elapsed = 1;
1074 		}
1075 		spin_unlock_irqrestore(&subs->lock, flags);
1076 		/* copy a data chunk */
1077 		if (oldptr + bytes > runtime->buffer_size * stride) {
1078 			unsigned int bytes1 =
1079 					runtime->buffer_size * stride - oldptr;
1080 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1081 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1082 		} else {
1083 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1084 		}
1085 	}
1086 
1087 	if (period_elapsed)
1088 		snd_pcm_period_elapsed(subs->pcm_substream);
1089 }
1090 
1091 static void prepare_playback_urb(struct snd_usb_substream *subs,
1092 				 struct urb *urb)
1093 {
1094 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1095 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1096 	struct snd_urb_ctx *ctx = urb->context;
1097 	unsigned int counts, frames, bytes;
1098 	int i, stride, period_elapsed = 0;
1099 	unsigned long flags;
1100 
1101 	stride = runtime->frame_bits >> 3;
1102 
1103 	frames = 0;
1104 	urb->number_of_packets = 0;
1105 	spin_lock_irqsave(&subs->lock, flags);
1106 	for (i = 0; i < ctx->packets; i++) {
1107 		if (ctx->packet_size[i])
1108 			counts = ctx->packet_size[i];
1109 		else
1110 			counts = snd_usb_endpoint_next_packet_size(ep);
1111 
1112 		/* set up descriptor */
1113 		urb->iso_frame_desc[i].offset = frames * stride;
1114 		urb->iso_frame_desc[i].length = counts * stride;
1115 		frames += counts;
1116 		urb->number_of_packets++;
1117 		subs->transfer_done += counts;
1118 		if (subs->transfer_done >= runtime->period_size) {
1119 			subs->transfer_done -= runtime->period_size;
1120 			period_elapsed = 1;
1121 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1122 				if (subs->transfer_done > 0) {
1123 					/* FIXME: fill-max mode is not
1124 					 * supported yet */
1125 					frames -= subs->transfer_done;
1126 					counts -= subs->transfer_done;
1127 					urb->iso_frame_desc[i].length =
1128 						counts * stride;
1129 					subs->transfer_done = 0;
1130 				}
1131 				i++;
1132 				if (i < ctx->packets) {
1133 					/* add a transfer delimiter */
1134 					urb->iso_frame_desc[i].offset =
1135 						frames * stride;
1136 					urb->iso_frame_desc[i].length = 0;
1137 					urb->number_of_packets++;
1138 				}
1139 				break;
1140 			}
1141 		}
1142 		if (period_elapsed &&
1143 		    !snd_usb_endpoint_implict_feedback_sink(subs->data_endpoint)) /* finish at the period boundary */
1144 			break;
1145 	}
1146 	bytes = frames * stride;
1147 	if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1148 		/* err, the transferred area goes over buffer boundary. */
1149 		unsigned int bytes1 =
1150 			runtime->buffer_size * stride - subs->hwptr_done;
1151 		memcpy(urb->transfer_buffer,
1152 		       runtime->dma_area + subs->hwptr_done, bytes1);
1153 		memcpy(urb->transfer_buffer + bytes1,
1154 		       runtime->dma_area, bytes - bytes1);
1155 	} else {
1156 		memcpy(urb->transfer_buffer,
1157 		       runtime->dma_area + subs->hwptr_done, bytes);
1158 	}
1159 	subs->hwptr_done += bytes;
1160 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1161 		subs->hwptr_done -= runtime->buffer_size * stride;
1162 
1163 	/* update delay with exact number of samples queued */
1164 	runtime->delay = subs->last_delay;
1165 	runtime->delay += frames;
1166 	subs->last_delay = runtime->delay;
1167 
1168 	/* realign last_frame_number */
1169 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1170 	subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1171 
1172 	spin_unlock_irqrestore(&subs->lock, flags);
1173 	urb->transfer_buffer_length = bytes;
1174 	if (period_elapsed)
1175 		snd_pcm_period_elapsed(subs->pcm_substream);
1176 }
1177 
1178 /*
1179  * process after playback data complete
1180  * - decrease the delay count again
1181  */
1182 static void retire_playback_urb(struct snd_usb_substream *subs,
1183 			       struct urb *urb)
1184 {
1185 	unsigned long flags;
1186 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1187 	int stride = runtime->frame_bits >> 3;
1188 	int processed = urb->transfer_buffer_length / stride;
1189 	int est_delay;
1190 
1191 	/* ignore the delay accounting when procssed=0 is given, i.e.
1192 	 * silent payloads are procssed before handling the actual data
1193 	 */
1194 	if (!processed)
1195 		return;
1196 
1197 	spin_lock_irqsave(&subs->lock, flags);
1198 	est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1199 	/* update delay with exact number of samples played */
1200 	if (processed > subs->last_delay)
1201 		subs->last_delay = 0;
1202 	else
1203 		subs->last_delay -= processed;
1204 	runtime->delay = subs->last_delay;
1205 
1206 	/*
1207 	 * Report when delay estimate is off by more than 2ms.
1208 	 * The error should be lower than 2ms since the estimate relies
1209 	 * on two reads of a counter updated every ms.
1210 	 */
1211 	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1212 		snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
1213 			est_delay, subs->last_delay);
1214 
1215 	spin_unlock_irqrestore(&subs->lock, flags);
1216 }
1217 
1218 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1219 {
1220 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1221 }
1222 
1223 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1224 {
1225 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1226 }
1227 
1228 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1229 {
1230 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1231 }
1232 
1233 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1234 {
1235 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1236 }
1237 
1238 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1239 					      int cmd)
1240 {
1241 	struct snd_usb_substream *subs = substream->runtime->private_data;
1242 
1243 	switch (cmd) {
1244 	case SNDRV_PCM_TRIGGER_START:
1245 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1246 		subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1247 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1248 		subs->running = 1;
1249 		return 0;
1250 	case SNDRV_PCM_TRIGGER_STOP:
1251 		stop_endpoints(subs, 0, 0, 0);
1252 		subs->running = 0;
1253 		return 0;
1254 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1255 		subs->data_endpoint->prepare_data_urb = NULL;
1256 		subs->data_endpoint->retire_data_urb = NULL;
1257 		subs->running = 0;
1258 		return 0;
1259 	}
1260 
1261 	return -EINVAL;
1262 }
1263 
1264 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1265 					     int cmd)
1266 {
1267 	int err;
1268 	struct snd_usb_substream *subs = substream->runtime->private_data;
1269 
1270 	switch (cmd) {
1271 	case SNDRV_PCM_TRIGGER_START:
1272 		err = start_endpoints(subs, 0);
1273 		if (err < 0)
1274 			return err;
1275 
1276 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1277 		subs->running = 1;
1278 		return 0;
1279 	case SNDRV_PCM_TRIGGER_STOP:
1280 		stop_endpoints(subs, 0, 0, 0);
1281 		subs->running = 0;
1282 		return 0;
1283 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1284 		subs->data_endpoint->retire_data_urb = NULL;
1285 		subs->running = 0;
1286 		return 0;
1287 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1288 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1289 		subs->running = 1;
1290 		return 0;
1291 	}
1292 
1293 	return -EINVAL;
1294 }
1295 
1296 static struct snd_pcm_ops snd_usb_playback_ops = {
1297 	.open =		snd_usb_playback_open,
1298 	.close =	snd_usb_playback_close,
1299 	.ioctl =	snd_pcm_lib_ioctl,
1300 	.hw_params =	snd_usb_hw_params,
1301 	.hw_free =	snd_usb_hw_free,
1302 	.prepare =	snd_usb_pcm_prepare,
1303 	.trigger =	snd_usb_substream_playback_trigger,
1304 	.pointer =	snd_usb_pcm_pointer,
1305 	.page =		snd_pcm_lib_get_vmalloc_page,
1306 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1307 };
1308 
1309 static struct snd_pcm_ops snd_usb_capture_ops = {
1310 	.open =		snd_usb_capture_open,
1311 	.close =	snd_usb_capture_close,
1312 	.ioctl =	snd_pcm_lib_ioctl,
1313 	.hw_params =	snd_usb_hw_params,
1314 	.hw_free =	snd_usb_hw_free,
1315 	.prepare =	snd_usb_pcm_prepare,
1316 	.trigger =	snd_usb_substream_capture_trigger,
1317 	.pointer =	snd_usb_pcm_pointer,
1318 	.page =		snd_pcm_lib_get_vmalloc_page,
1319 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1320 };
1321 
1322 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1323 {
1324 	snd_pcm_set_ops(pcm, stream,
1325 			stream == SNDRV_PCM_STREAM_PLAYBACK ?
1326 			&snd_usb_playback_ops : &snd_usb_capture_ops);
1327 }
1328