xref: /linux/sound/usb/pcm.c (revision a5d9265e017f081f0dc133c0e2f45103d027b874)
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/bitrev.h>
20 #include <linux/ratelimit.h>
21 #include <linux/usb.h>
22 #include <linux/usb/audio.h>
23 #include <linux/usb/audio-v2.h>
24 
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 
29 #include "usbaudio.h"
30 #include "card.h"
31 #include "quirks.h"
32 #include "debug.h"
33 #include "endpoint.h"
34 #include "helper.h"
35 #include "pcm.h"
36 #include "clock.h"
37 #include "power.h"
38 
39 #define SUBSTREAM_FLAG_DATA_EP_STARTED	0
40 #define SUBSTREAM_FLAG_SYNC_EP_STARTED	1
41 
42 /* return the estimated delay based on USB frame counters */
43 snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,
44 				    unsigned int rate)
45 {
46 	int current_frame_number;
47 	int frame_diff;
48 	int est_delay;
49 
50 	if (!subs->last_delay)
51 		return 0; /* short path */
52 
53 	current_frame_number = usb_get_current_frame_number(subs->dev);
54 	/*
55 	 * HCD implementations use different widths, use lower 8 bits.
56 	 * The delay will be managed up to 256ms, which is more than
57 	 * enough
58 	 */
59 	frame_diff = (current_frame_number - subs->last_frame_number) & 0xff;
60 
61 	/* Approximation based on number of samples per USB frame (ms),
62 	   some truncation for 44.1 but the estimate is good enough */
63 	est_delay =  frame_diff * rate / 1000;
64 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
65 		est_delay = subs->last_delay - est_delay;
66 	else
67 		est_delay = subs->last_delay + est_delay;
68 
69 	if (est_delay < 0)
70 		est_delay = 0;
71 	return est_delay;
72 }
73 
74 /*
75  * return the current pcm pointer.  just based on the hwptr_done value.
76  */
77 static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream)
78 {
79 	struct snd_usb_substream *subs = substream->runtime->private_data;
80 	unsigned int hwptr_done;
81 
82 	if (atomic_read(&subs->stream->chip->shutdown))
83 		return SNDRV_PCM_POS_XRUN;
84 	spin_lock(&subs->lock);
85 	hwptr_done = subs->hwptr_done;
86 	substream->runtime->delay = snd_usb_pcm_delay(subs,
87 						substream->runtime->rate);
88 	spin_unlock(&subs->lock);
89 	return hwptr_done / (substream->runtime->frame_bits >> 3);
90 }
91 
92 /*
93  * find a matching audio format
94  */
95 static struct audioformat *find_format(struct snd_usb_substream *subs)
96 {
97 	struct audioformat *fp;
98 	struct audioformat *found = NULL;
99 	int cur_attr = 0, attr;
100 
101 	list_for_each_entry(fp, &subs->fmt_list, list) {
102 		if (!(fp->formats & pcm_format_to_bits(subs->pcm_format)))
103 			continue;
104 		if (fp->channels != subs->channels)
105 			continue;
106 		if (subs->cur_rate < fp->rate_min ||
107 		    subs->cur_rate > fp->rate_max)
108 			continue;
109 		if (! (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
110 			unsigned int i;
111 			for (i = 0; i < fp->nr_rates; i++)
112 				if (fp->rate_table[i] == subs->cur_rate)
113 					break;
114 			if (i >= fp->nr_rates)
115 				continue;
116 		}
117 		attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
118 		if (! found) {
119 			found = fp;
120 			cur_attr = attr;
121 			continue;
122 		}
123 		/* avoid async out and adaptive in if the other method
124 		 * supports the same format.
125 		 * this is a workaround for the case like
126 		 * M-audio audiophile USB.
127 		 */
128 		if (attr != cur_attr) {
129 			if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
130 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
131 			    (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
132 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE))
133 				continue;
134 			if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
135 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
136 			    (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
137 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
138 				found = fp;
139 				cur_attr = attr;
140 				continue;
141 			}
142 		}
143 		/* find the format with the largest max. packet size */
144 		if (fp->maxpacksize > found->maxpacksize) {
145 			found = fp;
146 			cur_attr = attr;
147 		}
148 	}
149 	return found;
150 }
151 
152 static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
153 			 struct usb_host_interface *alts,
154 			 struct audioformat *fmt)
155 {
156 	struct usb_device *dev = chip->dev;
157 	unsigned int ep;
158 	unsigned char data[1];
159 	int err;
160 
161 	if (get_iface_desc(alts)->bNumEndpoints < 1)
162 		return -EINVAL;
163 	ep = get_endpoint(alts, 0)->bEndpointAddress;
164 
165 	data[0] = 1;
166 	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
167 			      USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
168 			      UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
169 			      data, sizeof(data));
170 	if (err < 0) {
171 		usb_audio_err(chip, "%d:%d: cannot set enable PITCH\n",
172 			      iface, ep);
173 		return err;
174 	}
175 
176 	return 0;
177 }
178 
179 static int init_pitch_v2(struct snd_usb_audio *chip, int iface,
180 			 struct usb_host_interface *alts,
181 			 struct audioformat *fmt)
182 {
183 	struct usb_device *dev = chip->dev;
184 	unsigned char data[1];
185 	int err;
186 
187 	data[0] = 1;
188 	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
189 			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
190 			      UAC2_EP_CS_PITCH << 8, 0,
191 			      data, sizeof(data));
192 	if (err < 0) {
193 		usb_audio_err(chip, "%d:%d: cannot set enable PITCH (v2)\n",
194 			      iface, fmt->altsetting);
195 		return err;
196 	}
197 
198 	return 0;
199 }
200 
201 /*
202  * initialize the pitch control and sample rate
203  */
204 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
205 		       struct usb_host_interface *alts,
206 		       struct audioformat *fmt)
207 {
208 	/* if endpoint doesn't have pitch control, bail out */
209 	if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
210 		return 0;
211 
212 	switch (fmt->protocol) {
213 	case UAC_VERSION_1:
214 	default:
215 		return init_pitch_v1(chip, iface, alts, fmt);
216 
217 	case UAC_VERSION_2:
218 		return init_pitch_v2(chip, iface, alts, fmt);
219 	}
220 }
221 
222 static int start_endpoints(struct snd_usb_substream *subs)
223 {
224 	int err;
225 
226 	if (!subs->data_endpoint)
227 		return -EINVAL;
228 
229 	if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
230 		struct snd_usb_endpoint *ep = subs->data_endpoint;
231 
232 		dev_dbg(&subs->dev->dev, "Starting data EP @%p\n", ep);
233 
234 		ep->data_subs = subs;
235 		err = snd_usb_endpoint_start(ep);
236 		if (err < 0) {
237 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
238 			return err;
239 		}
240 	}
241 
242 	if (subs->sync_endpoint &&
243 	    !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
244 		struct snd_usb_endpoint *ep = subs->sync_endpoint;
245 
246 		if (subs->data_endpoint->iface != subs->sync_endpoint->iface ||
247 		    subs->data_endpoint->altsetting != subs->sync_endpoint->altsetting) {
248 			err = usb_set_interface(subs->dev,
249 						subs->sync_endpoint->iface,
250 						subs->sync_endpoint->altsetting);
251 			if (err < 0) {
252 				clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
253 				dev_err(&subs->dev->dev,
254 					   "%d:%d: cannot set interface (%d)\n",
255 					   subs->sync_endpoint->iface,
256 					   subs->sync_endpoint->altsetting, err);
257 				return -EIO;
258 			}
259 		}
260 
261 		dev_dbg(&subs->dev->dev, "Starting sync EP @%p\n", ep);
262 
263 		ep->sync_slave = subs->data_endpoint;
264 		err = snd_usb_endpoint_start(ep);
265 		if (err < 0) {
266 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
267 			return err;
268 		}
269 	}
270 
271 	return 0;
272 }
273 
274 static void stop_endpoints(struct snd_usb_substream *subs, bool wait)
275 {
276 	if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags))
277 		snd_usb_endpoint_stop(subs->sync_endpoint);
278 
279 	if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags))
280 		snd_usb_endpoint_stop(subs->data_endpoint);
281 
282 	if (wait) {
283 		snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
284 		snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
285 	}
286 }
287 
288 static int search_roland_implicit_fb(struct usb_device *dev, int ifnum,
289 				     unsigned int altsetting,
290 				     struct usb_host_interface **alts,
291 				     unsigned int *ep)
292 {
293 	struct usb_interface *iface;
294 	struct usb_interface_descriptor *altsd;
295 	struct usb_endpoint_descriptor *epd;
296 
297 	iface = usb_ifnum_to_if(dev, ifnum);
298 	if (!iface || iface->num_altsetting < altsetting + 1)
299 		return -ENOENT;
300 	*alts = &iface->altsetting[altsetting];
301 	altsd = get_iface_desc(*alts);
302 	if (altsd->bAlternateSetting != altsetting ||
303 	    altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC ||
304 	    (altsd->bInterfaceSubClass != 2 &&
305 	     altsd->bInterfaceProtocol != 2   ) ||
306 	    altsd->bNumEndpoints < 1)
307 		return -ENOENT;
308 	epd = get_endpoint(*alts, 0);
309 	if (!usb_endpoint_is_isoc_in(epd) ||
310 	    (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
311 					USB_ENDPOINT_USAGE_IMPLICIT_FB)
312 		return -ENOENT;
313 	*ep = epd->bEndpointAddress;
314 	return 0;
315 }
316 
317 /* Setup an implicit feedback endpoint from a quirk. Returns 0 if no quirk
318  * applies. Returns 1 if a quirk was found.
319  */
320 static int set_sync_ep_implicit_fb_quirk(struct snd_usb_substream *subs,
321 					 struct usb_device *dev,
322 					 struct usb_interface_descriptor *altsd,
323 					 unsigned int attr)
324 {
325 	struct usb_host_interface *alts;
326 	struct usb_interface *iface;
327 	unsigned int ep;
328 	unsigned int ifnum;
329 
330 	/* Implicit feedback sync EPs consumers are always playback EPs */
331 	if (subs->direction != SNDRV_PCM_STREAM_PLAYBACK)
332 		return 0;
333 
334 	switch (subs->stream->chip->usb_id) {
335 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
336 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
337 		ep = 0x81;
338 		ifnum = 3;
339 		goto add_sync_ep_from_ifnum;
340 	case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
341 	case USB_ID(0x0763, 0x2081):
342 		ep = 0x81;
343 		ifnum = 2;
344 		goto add_sync_ep_from_ifnum;
345 	case USB_ID(0x2466, 0x8003): /* Fractal Audio Axe-Fx II */
346 		ep = 0x86;
347 		ifnum = 2;
348 		goto add_sync_ep_from_ifnum;
349 	case USB_ID(0x2466, 0x8010): /* Fractal Audio Axe-Fx III */
350 		ep = 0x81;
351 		ifnum = 2;
352 		goto add_sync_ep_from_ifnum;
353 	case USB_ID(0x1397, 0x0002): /* Behringer UFX1204 */
354 		ep = 0x81;
355 		ifnum = 1;
356 		goto add_sync_ep_from_ifnum;
357 	}
358 
359 	if (attr == USB_ENDPOINT_SYNC_ASYNC &&
360 	    altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
361 	    altsd->bInterfaceProtocol == 2 &&
362 	    altsd->bNumEndpoints == 1 &&
363 	    USB_ID_VENDOR(subs->stream->chip->usb_id) == 0x0582 /* Roland */ &&
364 	    search_roland_implicit_fb(dev, altsd->bInterfaceNumber + 1,
365 				      altsd->bAlternateSetting,
366 				      &alts, &ep) >= 0) {
367 		goto add_sync_ep;
368 	}
369 
370 	/* No quirk */
371 	return 0;
372 
373 add_sync_ep_from_ifnum:
374 	iface = usb_ifnum_to_if(dev, ifnum);
375 
376 	if (!iface || iface->num_altsetting == 0)
377 		return -EINVAL;
378 
379 	alts = &iface->altsetting[1];
380 
381 add_sync_ep:
382 	subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
383 						   alts, ep, !subs->direction,
384 						   SND_USB_ENDPOINT_TYPE_DATA);
385 	if (!subs->sync_endpoint)
386 		return -EINVAL;
387 
388 	subs->data_endpoint->sync_master = subs->sync_endpoint;
389 
390 	return 1;
391 }
392 
393 static int set_sync_endpoint(struct snd_usb_substream *subs,
394 			     struct audioformat *fmt,
395 			     struct usb_device *dev,
396 			     struct usb_host_interface *alts,
397 			     struct usb_interface_descriptor *altsd)
398 {
399 	int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
400 	unsigned int ep, attr;
401 	bool implicit_fb;
402 	int err;
403 
404 	/* we need a sync pipe in async OUT or adaptive IN mode */
405 	/* check the number of EP, since some devices have broken
406 	 * descriptors which fool us.  if it has only one EP,
407 	 * assume it as adaptive-out or sync-in.
408 	 */
409 	attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
410 
411 	if ((is_playback && (attr != USB_ENDPOINT_SYNC_ASYNC)) ||
412 		(!is_playback && (attr != USB_ENDPOINT_SYNC_ADAPTIVE))) {
413 
414 		/*
415 		 * In these modes the notion of sync_endpoint is irrelevant.
416 		 * Reset pointers to avoid using stale data from previously
417 		 * used settings, e.g. when configuration and endpoints were
418 		 * changed
419 		 */
420 
421 		subs->sync_endpoint = NULL;
422 		subs->data_endpoint->sync_master = NULL;
423 	}
424 
425 	err = set_sync_ep_implicit_fb_quirk(subs, dev, altsd, attr);
426 	if (err < 0)
427 		return err;
428 
429 	/* endpoint set by quirk */
430 	if (err > 0)
431 		return 0;
432 
433 	if (altsd->bNumEndpoints < 2)
434 		return 0;
435 
436 	if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
437 			     attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
438 	    (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
439 		return 0;
440 
441 	/*
442 	 * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
443 	 * if we don't find a sync endpoint, as on M-Audio Transit. In case of
444 	 * error fall back to SYNC mode and don't create sync endpoint
445 	 */
446 
447 	/* check sync-pipe endpoint */
448 	/* ... and check descriptor size before accessing bSynchAddress
449 	   because there is a version of the SB Audigy 2 NX firmware lacking
450 	   the audio fields in the endpoint descriptors */
451 	if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
452 	    (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
453 	     get_endpoint(alts, 1)->bSynchAddress != 0)) {
454 		dev_err(&dev->dev,
455 			"%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
456 			   fmt->iface, fmt->altsetting,
457 			   get_endpoint(alts, 1)->bmAttributes,
458 			   get_endpoint(alts, 1)->bLength,
459 			   get_endpoint(alts, 1)->bSynchAddress);
460 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
461 			return 0;
462 		return -EINVAL;
463 	}
464 	ep = get_endpoint(alts, 1)->bEndpointAddress;
465 	if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
466 	    ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
467 	     (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
468 		dev_err(&dev->dev,
469 			"%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
470 			   fmt->iface, fmt->altsetting,
471 			   is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
472 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
473 			return 0;
474 		return -EINVAL;
475 	}
476 
477 	implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
478 			== USB_ENDPOINT_USAGE_IMPLICIT_FB;
479 
480 	subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
481 						   alts, ep, !subs->direction,
482 						   implicit_fb ?
483 							SND_USB_ENDPOINT_TYPE_DATA :
484 							SND_USB_ENDPOINT_TYPE_SYNC);
485 	if (!subs->sync_endpoint) {
486 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
487 			return 0;
488 		return -EINVAL;
489 	}
490 
491 	subs->data_endpoint->sync_master = subs->sync_endpoint;
492 
493 	return 0;
494 }
495 
496 /*
497  * find a matching format and set up the interface
498  */
499 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
500 {
501 	struct usb_device *dev = subs->dev;
502 	struct usb_host_interface *alts;
503 	struct usb_interface_descriptor *altsd;
504 	struct usb_interface *iface;
505 	int err;
506 
507 	iface = usb_ifnum_to_if(dev, fmt->iface);
508 	if (WARN_ON(!iface))
509 		return -EINVAL;
510 	alts = usb_altnum_to_altsetting(iface, fmt->altsetting);
511 	altsd = get_iface_desc(alts);
512 	if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
513 		return -EINVAL;
514 
515 	if (fmt == subs->cur_audiofmt)
516 		return 0;
517 
518 	/* close the old interface */
519 	if (subs->interface >= 0 && subs->interface != fmt->iface) {
520 		if (!subs->stream->chip->keep_iface) {
521 			err = usb_set_interface(subs->dev, subs->interface, 0);
522 			if (err < 0) {
523 				dev_err(&dev->dev,
524 					"%d:%d: return to setting 0 failed (%d)\n",
525 					fmt->iface, fmt->altsetting, err);
526 				return -EIO;
527 			}
528 		}
529 		subs->interface = -1;
530 		subs->altset_idx = 0;
531 	}
532 
533 	/* set interface */
534 	if (iface->cur_altsetting != alts) {
535 		err = snd_usb_select_mode_quirk(subs, fmt);
536 		if (err < 0)
537 			return -EIO;
538 
539 		err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
540 		if (err < 0) {
541 			dev_err(&dev->dev,
542 				"%d:%d: usb_set_interface failed (%d)\n",
543 				fmt->iface, fmt->altsetting, err);
544 			return -EIO;
545 		}
546 		dev_dbg(&dev->dev, "setting usb interface %d:%d\n",
547 			fmt->iface, fmt->altsetting);
548 		snd_usb_set_interface_quirk(dev);
549 	}
550 
551 	subs->interface = fmt->iface;
552 	subs->altset_idx = fmt->altset_idx;
553 	subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
554 						   alts, fmt->endpoint, subs->direction,
555 						   SND_USB_ENDPOINT_TYPE_DATA);
556 
557 	if (!subs->data_endpoint)
558 		return -EINVAL;
559 
560 	err = set_sync_endpoint(subs, fmt, dev, alts, altsd);
561 	if (err < 0)
562 		return err;
563 
564 	err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt);
565 	if (err < 0)
566 		return err;
567 
568 	subs->cur_audiofmt = fmt;
569 
570 	snd_usb_set_format_quirk(subs, fmt);
571 
572 	return 0;
573 }
574 
575 /*
576  * Return the score of matching two audioformats.
577  * Veto the audioformat if:
578  * - It has no channels for some reason.
579  * - Requested PCM format is not supported.
580  * - Requested sample rate is not supported.
581  */
582 static int match_endpoint_audioformats(struct snd_usb_substream *subs,
583 				       struct audioformat *fp,
584 				       struct audioformat *match, int rate,
585 				       snd_pcm_format_t pcm_format)
586 {
587 	int i;
588 	int score = 0;
589 
590 	if (fp->channels < 1) {
591 		dev_dbg(&subs->dev->dev,
592 			"%s: (fmt @%p) no channels\n", __func__, fp);
593 		return 0;
594 	}
595 
596 	if (!(fp->formats & pcm_format_to_bits(pcm_format))) {
597 		dev_dbg(&subs->dev->dev,
598 			"%s: (fmt @%p) no match for format %d\n", __func__,
599 			fp, pcm_format);
600 		return 0;
601 	}
602 
603 	for (i = 0; i < fp->nr_rates; i++) {
604 		if (fp->rate_table[i] == rate) {
605 			score++;
606 			break;
607 		}
608 	}
609 	if (!score) {
610 		dev_dbg(&subs->dev->dev,
611 			"%s: (fmt @%p) no match for rate %d\n", __func__,
612 			fp, rate);
613 		return 0;
614 	}
615 
616 	if (fp->channels == match->channels)
617 		score++;
618 
619 	dev_dbg(&subs->dev->dev,
620 		"%s: (fmt @%p) score %d\n", __func__, fp, score);
621 
622 	return score;
623 }
624 
625 /*
626  * Configure the sync ep using the rate and pcm format of the data ep.
627  */
628 static int configure_sync_endpoint(struct snd_usb_substream *subs)
629 {
630 	int ret;
631 	struct audioformat *fp;
632 	struct audioformat *sync_fp = NULL;
633 	int cur_score = 0;
634 	int sync_period_bytes = subs->period_bytes;
635 	struct snd_usb_substream *sync_subs =
636 		&subs->stream->substream[subs->direction ^ 1];
637 
638 	if (subs->sync_endpoint->type != SND_USB_ENDPOINT_TYPE_DATA ||
639 	    !subs->stream)
640 		return snd_usb_endpoint_set_params(subs->sync_endpoint,
641 						   subs->pcm_format,
642 						   subs->channels,
643 						   subs->period_bytes,
644 						   0, 0,
645 						   subs->cur_rate,
646 						   subs->cur_audiofmt,
647 						   NULL);
648 
649 	/* Try to find the best matching audioformat. */
650 	list_for_each_entry(fp, &sync_subs->fmt_list, list) {
651 		int score = match_endpoint_audioformats(subs,
652 							fp, subs->cur_audiofmt,
653 			subs->cur_rate, subs->pcm_format);
654 
655 		if (score > cur_score) {
656 			sync_fp = fp;
657 			cur_score = score;
658 		}
659 	}
660 
661 	if (unlikely(sync_fp == NULL)) {
662 		dev_err(&subs->dev->dev,
663 			"%s: no valid audioformat for sync ep %x found\n",
664 			__func__, sync_subs->ep_num);
665 		return -EINVAL;
666 	}
667 
668 	/*
669 	 * Recalculate the period bytes if channel number differ between
670 	 * data and sync ep audioformat.
671 	 */
672 	if (sync_fp->channels != subs->channels) {
673 		sync_period_bytes = (subs->period_bytes / subs->channels) *
674 			sync_fp->channels;
675 		dev_dbg(&subs->dev->dev,
676 			"%s: adjusted sync ep period bytes (%d -> %d)\n",
677 			__func__, subs->period_bytes, sync_period_bytes);
678 	}
679 
680 	ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
681 					  subs->pcm_format,
682 					  sync_fp->channels,
683 					  sync_period_bytes,
684 					  0, 0,
685 					  subs->cur_rate,
686 					  sync_fp,
687 					  NULL);
688 
689 	return ret;
690 }
691 
692 /*
693  * configure endpoint params
694  *
695  * called  during initial setup and upon resume
696  */
697 static int configure_endpoint(struct snd_usb_substream *subs)
698 {
699 	int ret;
700 
701 	/* format changed */
702 	stop_endpoints(subs, true);
703 	ret = snd_usb_endpoint_set_params(subs->data_endpoint,
704 					  subs->pcm_format,
705 					  subs->channels,
706 					  subs->period_bytes,
707 					  subs->period_frames,
708 					  subs->buffer_periods,
709 					  subs->cur_rate,
710 					  subs->cur_audiofmt,
711 					  subs->sync_endpoint);
712 	if (ret < 0)
713 		return ret;
714 
715 	if (subs->sync_endpoint)
716 		ret = configure_sync_endpoint(subs);
717 
718 	return ret;
719 }
720 
721 static int snd_usb_pcm_change_state(struct snd_usb_substream *subs, int state)
722 {
723 	int ret;
724 
725 	if (!subs->str_pd)
726 		return 0;
727 
728 	ret = snd_usb_power_domain_set(subs->stream->chip, subs->str_pd, state);
729 	if (ret < 0) {
730 		dev_err(&subs->dev->dev,
731 			"Cannot change Power Domain ID: %d to state: %d. Err: %d\n",
732 			subs->str_pd->pd_id, state, ret);
733 		return ret;
734 	}
735 
736 	return 0;
737 }
738 
739 int snd_usb_pcm_suspend(struct snd_usb_stream *as)
740 {
741 	int ret;
742 
743 	ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D2);
744 	if (ret < 0)
745 		return ret;
746 
747 	ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D2);
748 	if (ret < 0)
749 		return ret;
750 
751 	return 0;
752 }
753 
754 int snd_usb_pcm_resume(struct snd_usb_stream *as)
755 {
756 	int ret;
757 
758 	ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D1);
759 	if (ret < 0)
760 		return ret;
761 
762 	ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D1);
763 	if (ret < 0)
764 		return ret;
765 
766 	return 0;
767 }
768 
769 /*
770  * hw_params callback
771  *
772  * allocate a buffer and set the given audio format.
773  *
774  * so far we use a physically linear buffer although packetize transfer
775  * doesn't need a continuous area.
776  * if sg buffer is supported on the later version of alsa, we'll follow
777  * that.
778  */
779 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
780 			     struct snd_pcm_hw_params *hw_params)
781 {
782 	struct snd_usb_substream *subs = substream->runtime->private_data;
783 	struct audioformat *fmt;
784 	int ret;
785 
786 	if (snd_usb_use_vmalloc)
787 		ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
788 						       params_buffer_bytes(hw_params));
789 	else
790 		ret = snd_pcm_lib_malloc_pages(substream,
791 					       params_buffer_bytes(hw_params));
792 	if (ret < 0)
793 		return ret;
794 
795 	subs->pcm_format = params_format(hw_params);
796 	subs->period_bytes = params_period_bytes(hw_params);
797 	subs->period_frames = params_period_size(hw_params);
798 	subs->buffer_periods = params_periods(hw_params);
799 	subs->channels = params_channels(hw_params);
800 	subs->cur_rate = params_rate(hw_params);
801 
802 	fmt = find_format(subs);
803 	if (!fmt) {
804 		dev_dbg(&subs->dev->dev,
805 			"cannot set format: format = %#x, rate = %d, channels = %d\n",
806 			   subs->pcm_format, subs->cur_rate, subs->channels);
807 		return -EINVAL;
808 	}
809 
810 	ret = snd_usb_lock_shutdown(subs->stream->chip);
811 	if (ret < 0)
812 		return ret;
813 
814 	ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
815 	if (ret < 0)
816 		goto unlock;
817 
818 	ret = set_format(subs, fmt);
819 	if (ret < 0)
820 		goto unlock;
821 
822 	subs->interface = fmt->iface;
823 	subs->altset_idx = fmt->altset_idx;
824 	subs->need_setup_ep = true;
825 
826  unlock:
827 	snd_usb_unlock_shutdown(subs->stream->chip);
828 	return ret;
829 }
830 
831 /*
832  * hw_free callback
833  *
834  * reset the audio format and release the buffer
835  */
836 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
837 {
838 	struct snd_usb_substream *subs = substream->runtime->private_data;
839 
840 	subs->cur_audiofmt = NULL;
841 	subs->cur_rate = 0;
842 	subs->period_bytes = 0;
843 	if (!snd_usb_lock_shutdown(subs->stream->chip)) {
844 		stop_endpoints(subs, true);
845 		snd_usb_endpoint_deactivate(subs->sync_endpoint);
846 		snd_usb_endpoint_deactivate(subs->data_endpoint);
847 		snd_usb_unlock_shutdown(subs->stream->chip);
848 	}
849 
850 	if (snd_usb_use_vmalloc)
851 		return snd_pcm_lib_free_vmalloc_buffer(substream);
852 	else
853 		return snd_pcm_lib_free_pages(substream);
854 }
855 
856 /*
857  * prepare callback
858  *
859  * only a few subtle things...
860  */
861 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
862 {
863 	struct snd_pcm_runtime *runtime = substream->runtime;
864 	struct snd_usb_substream *subs = runtime->private_data;
865 	struct usb_host_interface *alts;
866 	struct usb_interface *iface;
867 	int ret;
868 
869 	if (! subs->cur_audiofmt) {
870 		dev_err(&subs->dev->dev, "no format is specified!\n");
871 		return -ENXIO;
872 	}
873 
874 	ret = snd_usb_lock_shutdown(subs->stream->chip);
875 	if (ret < 0)
876 		return ret;
877 	if (snd_BUG_ON(!subs->data_endpoint)) {
878 		ret = -EIO;
879 		goto unlock;
880 	}
881 
882 	snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
883 	snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
884 
885 	ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
886 	if (ret < 0)
887 		goto unlock;
888 
889 	ret = set_format(subs, subs->cur_audiofmt);
890 	if (ret < 0)
891 		goto unlock;
892 
893 	if (subs->need_setup_ep) {
894 
895 		iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
896 		alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
897 		ret = snd_usb_init_sample_rate(subs->stream->chip,
898 					       subs->cur_audiofmt->iface,
899 					       alts,
900 					       subs->cur_audiofmt,
901 					       subs->cur_rate);
902 		if (ret < 0)
903 			goto unlock;
904 
905 		ret = configure_endpoint(subs);
906 		if (ret < 0)
907 			goto unlock;
908 		subs->need_setup_ep = false;
909 	}
910 
911 	/* some unit conversions in runtime */
912 	subs->data_endpoint->maxframesize =
913 		bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
914 	subs->data_endpoint->curframesize =
915 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
916 
917 	/* reset the pointer */
918 	subs->hwptr_done = 0;
919 	subs->transfer_done = 0;
920 	subs->last_delay = 0;
921 	subs->last_frame_number = 0;
922 	runtime->delay = 0;
923 
924 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
925 	 * updates for all URBs would happen at the same time when starting */
926 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
927 		ret = start_endpoints(subs);
928 
929  unlock:
930 	snd_usb_unlock_shutdown(subs->stream->chip);
931 	return ret;
932 }
933 
934 static const struct snd_pcm_hardware snd_usb_hardware =
935 {
936 	.info =			SNDRV_PCM_INFO_MMAP |
937 				SNDRV_PCM_INFO_MMAP_VALID |
938 				SNDRV_PCM_INFO_BATCH |
939 				SNDRV_PCM_INFO_INTERLEAVED |
940 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
941 				SNDRV_PCM_INFO_PAUSE,
942 	.buffer_bytes_max =	1024 * 1024,
943 	.period_bytes_min =	64,
944 	.period_bytes_max =	512 * 1024,
945 	.periods_min =		2,
946 	.periods_max =		1024,
947 };
948 
949 static int hw_check_valid_format(struct snd_usb_substream *subs,
950 				 struct snd_pcm_hw_params *params,
951 				 struct audioformat *fp)
952 {
953 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
954 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
955 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
956 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
957 	struct snd_mask check_fmts;
958 	unsigned int ptime;
959 
960 	/* check the format */
961 	snd_mask_none(&check_fmts);
962 	check_fmts.bits[0] = (u32)fp->formats;
963 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
964 	snd_mask_intersect(&check_fmts, fmts);
965 	if (snd_mask_empty(&check_fmts)) {
966 		hwc_debug("   > check: no supported format %d\n", fp->format);
967 		return 0;
968 	}
969 	/* check the channels */
970 	if (fp->channels < ct->min || fp->channels > ct->max) {
971 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
972 		return 0;
973 	}
974 	/* check the rate is within the range */
975 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
976 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
977 		return 0;
978 	}
979 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
980 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
981 		return 0;
982 	}
983 	/* check whether the period time is >= the data packet interval */
984 	if (subs->speed != USB_SPEED_FULL) {
985 		ptime = 125 * (1 << fp->datainterval);
986 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
987 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
988 			return 0;
989 		}
990 	}
991 	return 1;
992 }
993 
994 static int hw_rule_rate(struct snd_pcm_hw_params *params,
995 			struct snd_pcm_hw_rule *rule)
996 {
997 	struct snd_usb_substream *subs = rule->private;
998 	struct audioformat *fp;
999 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1000 	unsigned int rmin, rmax;
1001 	int changed;
1002 
1003 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
1004 	changed = 0;
1005 	rmin = rmax = 0;
1006 	list_for_each_entry(fp, &subs->fmt_list, list) {
1007 		if (!hw_check_valid_format(subs, params, fp))
1008 			continue;
1009 		if (changed++) {
1010 			if (rmin > fp->rate_min)
1011 				rmin = fp->rate_min;
1012 			if (rmax < fp->rate_max)
1013 				rmax = fp->rate_max;
1014 		} else {
1015 			rmin = fp->rate_min;
1016 			rmax = fp->rate_max;
1017 		}
1018 	}
1019 
1020 	if (!changed) {
1021 		hwc_debug("  --> get empty\n");
1022 		it->empty = 1;
1023 		return -EINVAL;
1024 	}
1025 
1026 	changed = 0;
1027 	if (it->min < rmin) {
1028 		it->min = rmin;
1029 		it->openmin = 0;
1030 		changed = 1;
1031 	}
1032 	if (it->max > rmax) {
1033 		it->max = rmax;
1034 		it->openmax = 0;
1035 		changed = 1;
1036 	}
1037 	if (snd_interval_checkempty(it)) {
1038 		it->empty = 1;
1039 		return -EINVAL;
1040 	}
1041 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1042 	return changed;
1043 }
1044 
1045 
1046 static int hw_rule_channels(struct snd_pcm_hw_params *params,
1047 			    struct snd_pcm_hw_rule *rule)
1048 {
1049 	struct snd_usb_substream *subs = rule->private;
1050 	struct audioformat *fp;
1051 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
1052 	unsigned int rmin, rmax;
1053 	int changed;
1054 
1055 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
1056 	changed = 0;
1057 	rmin = rmax = 0;
1058 	list_for_each_entry(fp, &subs->fmt_list, list) {
1059 		if (!hw_check_valid_format(subs, params, fp))
1060 			continue;
1061 		if (changed++) {
1062 			if (rmin > fp->channels)
1063 				rmin = fp->channels;
1064 			if (rmax < fp->channels)
1065 				rmax = fp->channels;
1066 		} else {
1067 			rmin = fp->channels;
1068 			rmax = fp->channels;
1069 		}
1070 	}
1071 
1072 	if (!changed) {
1073 		hwc_debug("  --> get empty\n");
1074 		it->empty = 1;
1075 		return -EINVAL;
1076 	}
1077 
1078 	changed = 0;
1079 	if (it->min < rmin) {
1080 		it->min = rmin;
1081 		it->openmin = 0;
1082 		changed = 1;
1083 	}
1084 	if (it->max > rmax) {
1085 		it->max = rmax;
1086 		it->openmax = 0;
1087 		changed = 1;
1088 	}
1089 	if (snd_interval_checkempty(it)) {
1090 		it->empty = 1;
1091 		return -EINVAL;
1092 	}
1093 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1094 	return changed;
1095 }
1096 
1097 static int hw_rule_format(struct snd_pcm_hw_params *params,
1098 			  struct snd_pcm_hw_rule *rule)
1099 {
1100 	struct snd_usb_substream *subs = rule->private;
1101 	struct audioformat *fp;
1102 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
1103 	u64 fbits;
1104 	u32 oldbits[2];
1105 	int changed;
1106 
1107 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
1108 	fbits = 0;
1109 	list_for_each_entry(fp, &subs->fmt_list, list) {
1110 		if (!hw_check_valid_format(subs, params, fp))
1111 			continue;
1112 		fbits |= fp->formats;
1113 	}
1114 
1115 	oldbits[0] = fmt->bits[0];
1116 	oldbits[1] = fmt->bits[1];
1117 	fmt->bits[0] &= (u32)fbits;
1118 	fmt->bits[1] &= (u32)(fbits >> 32);
1119 	if (!fmt->bits[0] && !fmt->bits[1]) {
1120 		hwc_debug("  --> get empty\n");
1121 		return -EINVAL;
1122 	}
1123 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
1124 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
1125 	return changed;
1126 }
1127 
1128 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
1129 			       struct snd_pcm_hw_rule *rule)
1130 {
1131 	struct snd_usb_substream *subs = rule->private;
1132 	struct audioformat *fp;
1133 	struct snd_interval *it;
1134 	unsigned char min_datainterval;
1135 	unsigned int pmin;
1136 	int changed;
1137 
1138 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
1139 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
1140 	min_datainterval = 0xff;
1141 	list_for_each_entry(fp, &subs->fmt_list, list) {
1142 		if (!hw_check_valid_format(subs, params, fp))
1143 			continue;
1144 		min_datainterval = min(min_datainterval, fp->datainterval);
1145 	}
1146 	if (min_datainterval == 0xff) {
1147 		hwc_debug("  --> get empty\n");
1148 		it->empty = 1;
1149 		return -EINVAL;
1150 	}
1151 	pmin = 125 * (1 << min_datainterval);
1152 	changed = 0;
1153 	if (it->min < pmin) {
1154 		it->min = pmin;
1155 		it->openmin = 0;
1156 		changed = 1;
1157 	}
1158 	if (snd_interval_checkempty(it)) {
1159 		it->empty = 1;
1160 		return -EINVAL;
1161 	}
1162 	hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
1163 	return changed;
1164 }
1165 
1166 /*
1167  *  If the device supports unusual bit rates, does the request meet these?
1168  */
1169 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
1170 				  struct snd_usb_substream *subs)
1171 {
1172 	struct audioformat *fp;
1173 	int *rate_list;
1174 	int count = 0, needs_knot = 0;
1175 	int err;
1176 
1177 	kfree(subs->rate_list.list);
1178 	subs->rate_list.list = NULL;
1179 
1180 	list_for_each_entry(fp, &subs->fmt_list, list) {
1181 		if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
1182 			return 0;
1183 		count += fp->nr_rates;
1184 		if (fp->rates & SNDRV_PCM_RATE_KNOT)
1185 			needs_knot = 1;
1186 	}
1187 	if (!needs_knot)
1188 		return 0;
1189 
1190 	subs->rate_list.list = rate_list =
1191 		kmalloc_array(count, sizeof(int), GFP_KERNEL);
1192 	if (!subs->rate_list.list)
1193 		return -ENOMEM;
1194 	subs->rate_list.count = count;
1195 	subs->rate_list.mask = 0;
1196 	count = 0;
1197 	list_for_each_entry(fp, &subs->fmt_list, list) {
1198 		int i;
1199 		for (i = 0; i < fp->nr_rates; i++)
1200 			rate_list[count++] = fp->rate_table[i];
1201 	}
1202 	err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1203 					 &subs->rate_list);
1204 	if (err < 0)
1205 		return err;
1206 
1207 	return 0;
1208 }
1209 
1210 
1211 /*
1212  * set up the runtime hardware information.
1213  */
1214 
1215 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1216 {
1217 	struct audioformat *fp;
1218 	unsigned int pt, ptmin;
1219 	int param_period_time_if_needed;
1220 	int err;
1221 
1222 	runtime->hw.formats = subs->formats;
1223 
1224 	runtime->hw.rate_min = 0x7fffffff;
1225 	runtime->hw.rate_max = 0;
1226 	runtime->hw.channels_min = 256;
1227 	runtime->hw.channels_max = 0;
1228 	runtime->hw.rates = 0;
1229 	ptmin = UINT_MAX;
1230 	/* check min/max rates and channels */
1231 	list_for_each_entry(fp, &subs->fmt_list, list) {
1232 		runtime->hw.rates |= fp->rates;
1233 		if (runtime->hw.rate_min > fp->rate_min)
1234 			runtime->hw.rate_min = fp->rate_min;
1235 		if (runtime->hw.rate_max < fp->rate_max)
1236 			runtime->hw.rate_max = fp->rate_max;
1237 		if (runtime->hw.channels_min > fp->channels)
1238 			runtime->hw.channels_min = fp->channels;
1239 		if (runtime->hw.channels_max < fp->channels)
1240 			runtime->hw.channels_max = fp->channels;
1241 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1242 			/* FIXME: there might be more than one audio formats... */
1243 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1244 				fp->frame_size;
1245 		}
1246 		pt = 125 * (1 << fp->datainterval);
1247 		ptmin = min(ptmin, pt);
1248 	}
1249 
1250 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1251 	if (subs->speed == USB_SPEED_FULL)
1252 		/* full speed devices have fixed data packet interval */
1253 		ptmin = 1000;
1254 	if (ptmin == 1000)
1255 		/* if period time doesn't go below 1 ms, no rules needed */
1256 		param_period_time_if_needed = -1;
1257 
1258 	err = snd_pcm_hw_constraint_minmax(runtime,
1259 					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1260 					   ptmin, UINT_MAX);
1261 	if (err < 0)
1262 		return err;
1263 
1264 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1265 				  hw_rule_rate, subs,
1266 				  SNDRV_PCM_HW_PARAM_FORMAT,
1267 				  SNDRV_PCM_HW_PARAM_CHANNELS,
1268 				  param_period_time_if_needed,
1269 				  -1);
1270 	if (err < 0)
1271 		return err;
1272 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1273 				  hw_rule_channels, subs,
1274 				  SNDRV_PCM_HW_PARAM_FORMAT,
1275 				  SNDRV_PCM_HW_PARAM_RATE,
1276 				  param_period_time_if_needed,
1277 				  -1);
1278 	if (err < 0)
1279 		return err;
1280 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1281 				  hw_rule_format, subs,
1282 				  SNDRV_PCM_HW_PARAM_RATE,
1283 				  SNDRV_PCM_HW_PARAM_CHANNELS,
1284 				  param_period_time_if_needed,
1285 				  -1);
1286 	if (err < 0)
1287 		return err;
1288 	if (param_period_time_if_needed >= 0) {
1289 		err = snd_pcm_hw_rule_add(runtime, 0,
1290 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1291 					  hw_rule_period_time, subs,
1292 					  SNDRV_PCM_HW_PARAM_FORMAT,
1293 					  SNDRV_PCM_HW_PARAM_CHANNELS,
1294 					  SNDRV_PCM_HW_PARAM_RATE,
1295 					  -1);
1296 		if (err < 0)
1297 			return err;
1298 	}
1299 	err = snd_usb_pcm_check_knot(runtime, subs);
1300 	if (err < 0)
1301 		return err;
1302 
1303 	return snd_usb_autoresume(subs->stream->chip);
1304 }
1305 
1306 static int snd_usb_pcm_open(struct snd_pcm_substream *substream)
1307 {
1308 	int direction = substream->stream;
1309 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1310 	struct snd_pcm_runtime *runtime = substream->runtime;
1311 	struct snd_usb_substream *subs = &as->substream[direction];
1312 
1313 	subs->interface = -1;
1314 	subs->altset_idx = 0;
1315 	runtime->hw = snd_usb_hardware;
1316 	runtime->private_data = subs;
1317 	subs->pcm_substream = substream;
1318 	/* runtime PM is also done there */
1319 
1320 	/* initialize DSD/DOP context */
1321 	subs->dsd_dop.byte_idx = 0;
1322 	subs->dsd_dop.channel = 0;
1323 	subs->dsd_dop.marker = 1;
1324 
1325 	return setup_hw_info(runtime, subs);
1326 }
1327 
1328 static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
1329 {
1330 	int direction = substream->stream;
1331 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1332 	struct snd_usb_substream *subs = &as->substream[direction];
1333 	int ret;
1334 
1335 	stop_endpoints(subs, true);
1336 
1337 	if (!as->chip->keep_iface &&
1338 	    subs->interface >= 0 &&
1339 	    !snd_usb_lock_shutdown(subs->stream->chip)) {
1340 		usb_set_interface(subs->dev, subs->interface, 0);
1341 		subs->interface = -1;
1342 		ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
1343 		snd_usb_unlock_shutdown(subs->stream->chip);
1344 		if (ret < 0)
1345 			return ret;
1346 	}
1347 
1348 	subs->pcm_substream = NULL;
1349 	snd_usb_autosuspend(subs->stream->chip);
1350 
1351 	return 0;
1352 }
1353 
1354 /* Since a URB can handle only a single linear buffer, we must use double
1355  * buffering when the data to be transferred overflows the buffer boundary.
1356  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1357  * for all URBs.
1358  */
1359 static void retire_capture_urb(struct snd_usb_substream *subs,
1360 			       struct urb *urb)
1361 {
1362 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1363 	unsigned int stride, frames, bytes, oldptr;
1364 	int i, period_elapsed = 0;
1365 	unsigned long flags;
1366 	unsigned char *cp;
1367 	int current_frame_number;
1368 
1369 	/* read frame number here, update pointer in critical section */
1370 	current_frame_number = usb_get_current_frame_number(subs->dev);
1371 
1372 	stride = runtime->frame_bits >> 3;
1373 
1374 	for (i = 0; i < urb->number_of_packets; i++) {
1375 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1376 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1377 			dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1378 				i, urb->iso_frame_desc[i].status);
1379 			// continue;
1380 		}
1381 		bytes = urb->iso_frame_desc[i].actual_length;
1382 		frames = bytes / stride;
1383 		if (!subs->txfr_quirk)
1384 			bytes = frames * stride;
1385 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1386 			int oldbytes = bytes;
1387 			bytes = frames * stride;
1388 			dev_warn_ratelimited(&subs->dev->dev,
1389 				 "Corrected urb data len. %d->%d\n",
1390 							oldbytes, bytes);
1391 		}
1392 		/* update the current pointer */
1393 		spin_lock_irqsave(&subs->lock, flags);
1394 		oldptr = subs->hwptr_done;
1395 		subs->hwptr_done += bytes;
1396 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1397 			subs->hwptr_done -= runtime->buffer_size * stride;
1398 		frames = (bytes + (oldptr % stride)) / stride;
1399 		subs->transfer_done += frames;
1400 		if (subs->transfer_done >= runtime->period_size) {
1401 			subs->transfer_done -= runtime->period_size;
1402 			period_elapsed = 1;
1403 		}
1404 		/* capture delay is by construction limited to one URB,
1405 		 * reset delays here
1406 		 */
1407 		runtime->delay = subs->last_delay = 0;
1408 
1409 		/* realign last_frame_number */
1410 		subs->last_frame_number = current_frame_number;
1411 		subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1412 
1413 		spin_unlock_irqrestore(&subs->lock, flags);
1414 		/* copy a data chunk */
1415 		if (oldptr + bytes > runtime->buffer_size * stride) {
1416 			unsigned int bytes1 =
1417 					runtime->buffer_size * stride - oldptr;
1418 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1419 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1420 		} else {
1421 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1422 		}
1423 	}
1424 
1425 	if (period_elapsed)
1426 		snd_pcm_period_elapsed(subs->pcm_substream);
1427 }
1428 
1429 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1430 					     struct urb *urb, unsigned int bytes)
1431 {
1432 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1433 	unsigned int stride = runtime->frame_bits >> 3;
1434 	unsigned int dst_idx = 0;
1435 	unsigned int src_idx = subs->hwptr_done;
1436 	unsigned int wrap = runtime->buffer_size * stride;
1437 	u8 *dst = urb->transfer_buffer;
1438 	u8 *src = runtime->dma_area;
1439 	u8 marker[] = { 0x05, 0xfa };
1440 
1441 	/*
1442 	 * The DSP DOP format defines a way to transport DSD samples over
1443 	 * normal PCM data endpoints. It requires stuffing of marker bytes
1444 	 * (0x05 and 0xfa, alternating per sample frame), and then expects
1445 	 * 2 additional bytes of actual payload. The whole frame is stored
1446 	 * LSB.
1447 	 *
1448 	 * Hence, for a stereo transport, the buffer layout looks like this,
1449 	 * where L refers to left channel samples and R to right.
1450 	 *
1451 	 *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1452 	 *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1453 	 *   .....
1454 	 *
1455 	 */
1456 
1457 	while (bytes--) {
1458 		if (++subs->dsd_dop.byte_idx == 3) {
1459 			/* frame boundary? */
1460 			dst[dst_idx++] = marker[subs->dsd_dop.marker];
1461 			src_idx += 2;
1462 			subs->dsd_dop.byte_idx = 0;
1463 
1464 			if (++subs->dsd_dop.channel % runtime->channels == 0) {
1465 				/* alternate the marker */
1466 				subs->dsd_dop.marker++;
1467 				subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1468 				subs->dsd_dop.channel = 0;
1469 			}
1470 		} else {
1471 			/* stuff the DSD payload */
1472 			int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1473 
1474 			if (subs->cur_audiofmt->dsd_bitrev)
1475 				dst[dst_idx++] = bitrev8(src[idx]);
1476 			else
1477 				dst[dst_idx++] = src[idx];
1478 
1479 			subs->hwptr_done++;
1480 		}
1481 	}
1482 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1483 		subs->hwptr_done -= runtime->buffer_size * stride;
1484 }
1485 
1486 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1487 			int offset, int stride, unsigned int bytes)
1488 {
1489 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1490 
1491 	if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1492 		/* err, the transferred area goes over buffer boundary. */
1493 		unsigned int bytes1 =
1494 			runtime->buffer_size * stride - subs->hwptr_done;
1495 		memcpy(urb->transfer_buffer + offset,
1496 		       runtime->dma_area + subs->hwptr_done, bytes1);
1497 		memcpy(urb->transfer_buffer + offset + bytes1,
1498 		       runtime->dma_area, bytes - bytes1);
1499 	} else {
1500 		memcpy(urb->transfer_buffer + offset,
1501 		       runtime->dma_area + subs->hwptr_done, bytes);
1502 	}
1503 	subs->hwptr_done += bytes;
1504 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1505 		subs->hwptr_done -= runtime->buffer_size * stride;
1506 }
1507 
1508 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1509 				      struct urb *urb, int stride,
1510 				      unsigned int bytes)
1511 {
1512 	__le32 packet_length;
1513 	int i;
1514 
1515 	/* Put __le32 length descriptor at start of each packet. */
1516 	for (i = 0; i < urb->number_of_packets; i++) {
1517 		unsigned int length = urb->iso_frame_desc[i].length;
1518 		unsigned int offset = urb->iso_frame_desc[i].offset;
1519 
1520 		packet_length = cpu_to_le32(length);
1521 		offset += i * sizeof(packet_length);
1522 		urb->iso_frame_desc[i].offset = offset;
1523 		urb->iso_frame_desc[i].length += sizeof(packet_length);
1524 		memcpy(urb->transfer_buffer + offset,
1525 		       &packet_length, sizeof(packet_length));
1526 		copy_to_urb(subs, urb, offset + sizeof(packet_length),
1527 			    stride, length);
1528 	}
1529 	/* Adjust transfer size accordingly. */
1530 	bytes += urb->number_of_packets * sizeof(packet_length);
1531 	return bytes;
1532 }
1533 
1534 static void prepare_playback_urb(struct snd_usb_substream *subs,
1535 				 struct urb *urb)
1536 {
1537 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1538 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1539 	struct snd_urb_ctx *ctx = urb->context;
1540 	unsigned int counts, frames, bytes;
1541 	int i, stride, period_elapsed = 0;
1542 	unsigned long flags;
1543 
1544 	stride = runtime->frame_bits >> 3;
1545 
1546 	frames = 0;
1547 	urb->number_of_packets = 0;
1548 	spin_lock_irqsave(&subs->lock, flags);
1549 	subs->frame_limit += ep->max_urb_frames;
1550 	for (i = 0; i < ctx->packets; i++) {
1551 		if (ctx->packet_size[i])
1552 			counts = ctx->packet_size[i];
1553 		else
1554 			counts = snd_usb_endpoint_next_packet_size(ep);
1555 
1556 		/* set up descriptor */
1557 		urb->iso_frame_desc[i].offset = frames * ep->stride;
1558 		urb->iso_frame_desc[i].length = counts * ep->stride;
1559 		frames += counts;
1560 		urb->number_of_packets++;
1561 		subs->transfer_done += counts;
1562 		if (subs->transfer_done >= runtime->period_size) {
1563 			subs->transfer_done -= runtime->period_size;
1564 			subs->frame_limit = 0;
1565 			period_elapsed = 1;
1566 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1567 				if (subs->transfer_done > 0) {
1568 					/* FIXME: fill-max mode is not
1569 					 * supported yet */
1570 					frames -= subs->transfer_done;
1571 					counts -= subs->transfer_done;
1572 					urb->iso_frame_desc[i].length =
1573 						counts * ep->stride;
1574 					subs->transfer_done = 0;
1575 				}
1576 				i++;
1577 				if (i < ctx->packets) {
1578 					/* add a transfer delimiter */
1579 					urb->iso_frame_desc[i].offset =
1580 						frames * ep->stride;
1581 					urb->iso_frame_desc[i].length = 0;
1582 					urb->number_of_packets++;
1583 				}
1584 				break;
1585 			}
1586 		}
1587 		/* finish at the period boundary or after enough frames */
1588 		if ((period_elapsed ||
1589 				subs->transfer_done >= subs->frame_limit) &&
1590 		    !snd_usb_endpoint_implicit_feedback_sink(ep))
1591 			break;
1592 	}
1593 	bytes = frames * ep->stride;
1594 
1595 	if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1596 		     subs->cur_audiofmt->dsd_dop)) {
1597 		fill_playback_urb_dsd_dop(subs, urb, bytes);
1598 	} else if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1599 			   subs->cur_audiofmt->dsd_bitrev)) {
1600 		/* bit-reverse the bytes */
1601 		u8 *buf = urb->transfer_buffer;
1602 		for (i = 0; i < bytes; i++) {
1603 			int idx = (subs->hwptr_done + i)
1604 				% (runtime->buffer_size * stride);
1605 			buf[i] = bitrev8(runtime->dma_area[idx]);
1606 		}
1607 
1608 		subs->hwptr_done += bytes;
1609 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1610 			subs->hwptr_done -= runtime->buffer_size * stride;
1611 	} else {
1612 		/* usual PCM */
1613 		if (!subs->tx_length_quirk)
1614 			copy_to_urb(subs, urb, 0, stride, bytes);
1615 		else
1616 			bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1617 			/* bytes is now amount of outgoing data */
1618 	}
1619 
1620 	/* update delay with exact number of samples queued */
1621 	runtime->delay = subs->last_delay;
1622 	runtime->delay += frames;
1623 	subs->last_delay = runtime->delay;
1624 
1625 	/* realign last_frame_number */
1626 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1627 	subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1628 
1629 	if (subs->trigger_tstamp_pending_update) {
1630 		/* this is the first actual URB submitted,
1631 		 * update trigger timestamp to reflect actual start time
1632 		 */
1633 		snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1634 		subs->trigger_tstamp_pending_update = false;
1635 	}
1636 
1637 	spin_unlock_irqrestore(&subs->lock, flags);
1638 	urb->transfer_buffer_length = bytes;
1639 	if (period_elapsed)
1640 		snd_pcm_period_elapsed(subs->pcm_substream);
1641 }
1642 
1643 /*
1644  * process after playback data complete
1645  * - decrease the delay count again
1646  */
1647 static void retire_playback_urb(struct snd_usb_substream *subs,
1648 			       struct urb *urb)
1649 {
1650 	unsigned long flags;
1651 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1652 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1653 	int processed = urb->transfer_buffer_length / ep->stride;
1654 	int est_delay;
1655 
1656 	/* ignore the delay accounting when procssed=0 is given, i.e.
1657 	 * silent payloads are procssed before handling the actual data
1658 	 */
1659 	if (!processed)
1660 		return;
1661 
1662 	spin_lock_irqsave(&subs->lock, flags);
1663 	if (!subs->last_delay)
1664 		goto out; /* short path */
1665 
1666 	est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1667 	/* update delay with exact number of samples played */
1668 	if (processed > subs->last_delay)
1669 		subs->last_delay = 0;
1670 	else
1671 		subs->last_delay -= processed;
1672 	runtime->delay = subs->last_delay;
1673 
1674 	/*
1675 	 * Report when delay estimate is off by more than 2ms.
1676 	 * The error should be lower than 2ms since the estimate relies
1677 	 * on two reads of a counter updated every ms.
1678 	 */
1679 	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1680 		dev_dbg_ratelimited(&subs->dev->dev,
1681 			"delay: estimated %d, actual %d\n",
1682 			est_delay, subs->last_delay);
1683 
1684 	if (!subs->running) {
1685 		/* update last_frame_number for delay counting here since
1686 		 * prepare_playback_urb won't be called during pause
1687 		 */
1688 		subs->last_frame_number =
1689 			usb_get_current_frame_number(subs->dev) & 0xff;
1690 	}
1691 
1692  out:
1693 	spin_unlock_irqrestore(&subs->lock, flags);
1694 }
1695 
1696 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1697 					      int cmd)
1698 {
1699 	struct snd_usb_substream *subs = substream->runtime->private_data;
1700 
1701 	switch (cmd) {
1702 	case SNDRV_PCM_TRIGGER_START:
1703 		subs->trigger_tstamp_pending_update = true;
1704 		/* fall through */
1705 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1706 		subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1707 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1708 		subs->running = 1;
1709 		return 0;
1710 	case SNDRV_PCM_TRIGGER_STOP:
1711 		stop_endpoints(subs, false);
1712 		subs->running = 0;
1713 		return 0;
1714 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1715 		subs->data_endpoint->prepare_data_urb = NULL;
1716 		/* keep retire_data_urb for delay calculation */
1717 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1718 		subs->running = 0;
1719 		return 0;
1720 	}
1721 
1722 	return -EINVAL;
1723 }
1724 
1725 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1726 					     int cmd)
1727 {
1728 	int err;
1729 	struct snd_usb_substream *subs = substream->runtime->private_data;
1730 
1731 	switch (cmd) {
1732 	case SNDRV_PCM_TRIGGER_START:
1733 		err = start_endpoints(subs);
1734 		if (err < 0)
1735 			return err;
1736 
1737 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1738 		subs->running = 1;
1739 		return 0;
1740 	case SNDRV_PCM_TRIGGER_STOP:
1741 		stop_endpoints(subs, false);
1742 		subs->running = 0;
1743 		return 0;
1744 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1745 		subs->data_endpoint->retire_data_urb = NULL;
1746 		subs->running = 0;
1747 		return 0;
1748 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1749 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1750 		subs->running = 1;
1751 		return 0;
1752 	}
1753 
1754 	return -EINVAL;
1755 }
1756 
1757 static const struct snd_pcm_ops snd_usb_playback_ops = {
1758 	.open =		snd_usb_pcm_open,
1759 	.close =	snd_usb_pcm_close,
1760 	.ioctl =	snd_pcm_lib_ioctl,
1761 	.hw_params =	snd_usb_hw_params,
1762 	.hw_free =	snd_usb_hw_free,
1763 	.prepare =	snd_usb_pcm_prepare,
1764 	.trigger =	snd_usb_substream_playback_trigger,
1765 	.pointer =	snd_usb_pcm_pointer,
1766 	.page =		snd_pcm_lib_get_vmalloc_page,
1767 };
1768 
1769 static const struct snd_pcm_ops snd_usb_capture_ops = {
1770 	.open =		snd_usb_pcm_open,
1771 	.close =	snd_usb_pcm_close,
1772 	.ioctl =	snd_pcm_lib_ioctl,
1773 	.hw_params =	snd_usb_hw_params,
1774 	.hw_free =	snd_usb_hw_free,
1775 	.prepare =	snd_usb_pcm_prepare,
1776 	.trigger =	snd_usb_substream_capture_trigger,
1777 	.pointer =	snd_usb_pcm_pointer,
1778 	.page =		snd_pcm_lib_get_vmalloc_page,
1779 };
1780 
1781 static const struct snd_pcm_ops snd_usb_playback_dev_ops = {
1782 	.open =		snd_usb_pcm_open,
1783 	.close =	snd_usb_pcm_close,
1784 	.ioctl =	snd_pcm_lib_ioctl,
1785 	.hw_params =	snd_usb_hw_params,
1786 	.hw_free =	snd_usb_hw_free,
1787 	.prepare =	snd_usb_pcm_prepare,
1788 	.trigger =	snd_usb_substream_playback_trigger,
1789 	.pointer =	snd_usb_pcm_pointer,
1790 	.page =		snd_pcm_sgbuf_ops_page,
1791 };
1792 
1793 static const struct snd_pcm_ops snd_usb_capture_dev_ops = {
1794 	.open =		snd_usb_pcm_open,
1795 	.close =	snd_usb_pcm_close,
1796 	.ioctl =	snd_pcm_lib_ioctl,
1797 	.hw_params =	snd_usb_hw_params,
1798 	.hw_free =	snd_usb_hw_free,
1799 	.prepare =	snd_usb_pcm_prepare,
1800 	.trigger =	snd_usb_substream_capture_trigger,
1801 	.pointer =	snd_usb_pcm_pointer,
1802 	.page =		snd_pcm_sgbuf_ops_page,
1803 };
1804 
1805 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1806 {
1807 	const struct snd_pcm_ops *ops;
1808 
1809 	if (snd_usb_use_vmalloc)
1810 		ops = stream == SNDRV_PCM_STREAM_PLAYBACK ?
1811 			&snd_usb_playback_ops : &snd_usb_capture_ops;
1812 	else
1813 		ops = stream == SNDRV_PCM_STREAM_PLAYBACK ?
1814 			&snd_usb_playback_dev_ops : &snd_usb_capture_dev_ops;
1815 	snd_pcm_set_ops(pcm, stream, ops);
1816 }
1817 
1818 void snd_usb_preallocate_buffer(struct snd_usb_substream *subs)
1819 {
1820 	struct snd_pcm *pcm = subs->stream->pcm;
1821 	struct snd_pcm_substream *s = pcm->streams[subs->direction].substream;
1822 	struct device *dev = subs->dev->bus->controller;
1823 
1824 	if (!snd_usb_use_vmalloc)
1825 		snd_pcm_lib_preallocate_pages(s, SNDRV_DMA_TYPE_DEV_SG,
1826 					      dev, 64*1024, 512*1024);
1827 }
1828