xref: /linux/sound/usb/pcm.c (revision 74ce1896c6c65b2f8cccbf59162d542988835835)
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;
80 	unsigned int hwptr_done;
81 
82 	subs = (struct snd_usb_substream *)substream->runtime->private_data;
83 	if (atomic_read(&subs->stream->chip->shutdown))
84 		return SNDRV_PCM_POS_XRUN;
85 	spin_lock(&subs->lock);
86 	hwptr_done = subs->hwptr_done;
87 	substream->runtime->delay = snd_usb_pcm_delay(subs,
88 						substream->runtime->rate);
89 	spin_unlock(&subs->lock);
90 	return hwptr_done / (substream->runtime->frame_bits >> 3);
91 }
92 
93 /*
94  * find a matching audio format
95  */
96 static struct audioformat *find_format(struct snd_usb_substream *subs)
97 {
98 	struct audioformat *fp;
99 	struct audioformat *found = NULL;
100 	int cur_attr = 0, attr;
101 
102 	list_for_each_entry(fp, &subs->fmt_list, list) {
103 		if (!(fp->formats & pcm_format_to_bits(subs->pcm_format)))
104 			continue;
105 		if (fp->channels != subs->channels)
106 			continue;
107 		if (subs->cur_rate < fp->rate_min ||
108 		    subs->cur_rate > fp->rate_max)
109 			continue;
110 		if (! (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
111 			unsigned int i;
112 			for (i = 0; i < fp->nr_rates; i++)
113 				if (fp->rate_table[i] == subs->cur_rate)
114 					break;
115 			if (i >= fp->nr_rates)
116 				continue;
117 		}
118 		attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
119 		if (! found) {
120 			found = fp;
121 			cur_attr = attr;
122 			continue;
123 		}
124 		/* avoid async out and adaptive in if the other method
125 		 * supports the same format.
126 		 * this is a workaround for the case like
127 		 * M-audio audiophile USB.
128 		 */
129 		if (attr != cur_attr) {
130 			if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
131 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
132 			    (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
133 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE))
134 				continue;
135 			if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
136 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
137 			    (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
138 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
139 				found = fp;
140 				cur_attr = attr;
141 				continue;
142 			}
143 		}
144 		/* find the format with the largest max. packet size */
145 		if (fp->maxpacksize > found->maxpacksize) {
146 			found = fp;
147 			cur_attr = attr;
148 		}
149 	}
150 	return found;
151 }
152 
153 static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
154 			 struct usb_host_interface *alts,
155 			 struct audioformat *fmt)
156 {
157 	struct usb_device *dev = chip->dev;
158 	unsigned int ep;
159 	unsigned char data[1];
160 	int err;
161 
162 	if (get_iface_desc(alts)->bNumEndpoints < 1)
163 		return -EINVAL;
164 	ep = get_endpoint(alts, 0)->bEndpointAddress;
165 
166 	data[0] = 1;
167 	if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
168 				   USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
169 				   UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
170 				   data, sizeof(data))) < 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 	if ((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))) < 0) {
192 		usb_audio_err(chip, "%d:%d: cannot set enable PITCH (v2)\n",
193 			      iface, fmt->altsetting);
194 		return err;
195 	}
196 
197 	return 0;
198 }
199 
200 /*
201  * initialize the pitch control and sample rate
202  */
203 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
204 		       struct usb_host_interface *alts,
205 		       struct audioformat *fmt)
206 {
207 	/* if endpoint doesn't have pitch control, bail out */
208 	if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
209 		return 0;
210 
211 	switch (fmt->protocol) {
212 	case UAC_VERSION_1:
213 	default:
214 		return init_pitch_v1(chip, iface, alts, fmt);
215 
216 	case UAC_VERSION_2:
217 		return init_pitch_v2(chip, iface, alts, fmt);
218 	}
219 }
220 
221 static int start_endpoints(struct snd_usb_substream *subs)
222 {
223 	int err;
224 
225 	if (!subs->data_endpoint)
226 		return -EINVAL;
227 
228 	if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
229 		struct snd_usb_endpoint *ep = subs->data_endpoint;
230 
231 		dev_dbg(&subs->dev->dev, "Starting data EP @%p\n", ep);
232 
233 		ep->data_subs = subs;
234 		err = snd_usb_endpoint_start(ep);
235 		if (err < 0) {
236 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
237 			return err;
238 		}
239 	}
240 
241 	if (subs->sync_endpoint &&
242 	    !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
243 		struct snd_usb_endpoint *ep = subs->sync_endpoint;
244 
245 		if (subs->data_endpoint->iface != subs->sync_endpoint->iface ||
246 		    subs->data_endpoint->altsetting != subs->sync_endpoint->altsetting) {
247 			err = usb_set_interface(subs->dev,
248 						subs->sync_endpoint->iface,
249 						subs->sync_endpoint->altsetting);
250 			if (err < 0) {
251 				clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
252 				dev_err(&subs->dev->dev,
253 					   "%d:%d: cannot set interface (%d)\n",
254 					   subs->sync_endpoint->iface,
255 					   subs->sync_endpoint->altsetting, err);
256 				return -EIO;
257 			}
258 		}
259 
260 		dev_dbg(&subs->dev->dev, "Starting sync EP @%p\n", ep);
261 
262 		ep->sync_slave = subs->data_endpoint;
263 		err = snd_usb_endpoint_start(ep);
264 		if (err < 0) {
265 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
266 			return err;
267 		}
268 	}
269 
270 	return 0;
271 }
272 
273 static void stop_endpoints(struct snd_usb_substream *subs, bool wait)
274 {
275 	if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags))
276 		snd_usb_endpoint_stop(subs->sync_endpoint);
277 
278 	if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags))
279 		snd_usb_endpoint_stop(subs->data_endpoint);
280 
281 	if (wait) {
282 		snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
283 		snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
284 	}
285 }
286 
287 static int search_roland_implicit_fb(struct usb_device *dev, int ifnum,
288 				     unsigned int altsetting,
289 				     struct usb_host_interface **alts,
290 				     unsigned int *ep)
291 {
292 	struct usb_interface *iface;
293 	struct usb_interface_descriptor *altsd;
294 	struct usb_endpoint_descriptor *epd;
295 
296 	iface = usb_ifnum_to_if(dev, ifnum);
297 	if (!iface || iface->num_altsetting < altsetting + 1)
298 		return -ENOENT;
299 	*alts = &iface->altsetting[altsetting];
300 	altsd = get_iface_desc(*alts);
301 	if (altsd->bAlternateSetting != altsetting ||
302 	    altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC ||
303 	    (altsd->bInterfaceSubClass != 2 &&
304 	     altsd->bInterfaceProtocol != 2   ) ||
305 	    altsd->bNumEndpoints < 1)
306 		return -ENOENT;
307 	epd = get_endpoint(*alts, 0);
308 	if (!usb_endpoint_is_isoc_in(epd) ||
309 	    (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
310 					USB_ENDPOINT_USAGE_IMPLICIT_FB)
311 		return -ENOENT;
312 	*ep = epd->bEndpointAddress;
313 	return 0;
314 }
315 
316 static int set_sync_ep_implicit_fb_quirk(struct snd_usb_substream *subs,
317 					 struct usb_device *dev,
318 					 struct usb_interface_descriptor *altsd,
319 					 unsigned int attr)
320 {
321 	struct usb_host_interface *alts;
322 	struct usb_interface *iface;
323 	unsigned int ep;
324 
325 	/* Implicit feedback sync EPs consumers are always playback EPs */
326 	if (subs->direction != SNDRV_PCM_STREAM_PLAYBACK)
327 		return 0;
328 
329 	switch (subs->stream->chip->usb_id) {
330 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
331 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
332 		ep = 0x81;
333 		iface = usb_ifnum_to_if(dev, 3);
334 
335 		if (!iface || iface->num_altsetting == 0)
336 			return -EINVAL;
337 
338 		alts = &iface->altsetting[1];
339 		goto add_sync_ep;
340 		break;
341 	case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
342 	case USB_ID(0x0763, 0x2081):
343 		ep = 0x81;
344 		iface = usb_ifnum_to_if(dev, 2);
345 
346 		if (!iface || iface->num_altsetting == 0)
347 			return -EINVAL;
348 
349 		alts = &iface->altsetting[1];
350 		goto add_sync_ep;
351 	case USB_ID(0x2466, 0x8003):
352 		ep = 0x86;
353 		iface = usb_ifnum_to_if(dev, 2);
354 
355 		if (!iface || iface->num_altsetting == 0)
356 			return -EINVAL;
357 
358 		alts = &iface->altsetting[1];
359 		goto add_sync_ep;
360 
361 	}
362 	if (attr == USB_ENDPOINT_SYNC_ASYNC &&
363 	    altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
364 	    altsd->bInterfaceProtocol == 2 &&
365 	    altsd->bNumEndpoints == 1 &&
366 	    USB_ID_VENDOR(subs->stream->chip->usb_id) == 0x0582 /* Roland */ &&
367 	    search_roland_implicit_fb(dev, altsd->bInterfaceNumber + 1,
368 				      altsd->bAlternateSetting,
369 				      &alts, &ep) >= 0) {
370 		goto add_sync_ep;
371 	}
372 
373 	/* No quirk */
374 	return 0;
375 
376 add_sync_ep:
377 	subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
378 						   alts, ep, !subs->direction,
379 						   SND_USB_ENDPOINT_TYPE_DATA);
380 	if (!subs->sync_endpoint)
381 		return -EINVAL;
382 
383 	subs->data_endpoint->sync_master = subs->sync_endpoint;
384 
385 	return 0;
386 }
387 
388 static int set_sync_endpoint(struct snd_usb_substream *subs,
389 			     struct audioformat *fmt,
390 			     struct usb_device *dev,
391 			     struct usb_host_interface *alts,
392 			     struct usb_interface_descriptor *altsd)
393 {
394 	int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
395 	unsigned int ep, attr;
396 	bool implicit_fb;
397 	int err;
398 
399 	/* we need a sync pipe in async OUT or adaptive IN mode */
400 	/* check the number of EP, since some devices have broken
401 	 * descriptors which fool us.  if it has only one EP,
402 	 * assume it as adaptive-out or sync-in.
403 	 */
404 	attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
405 
406 	if ((is_playback && (attr != USB_ENDPOINT_SYNC_ASYNC)) ||
407 		(!is_playback && (attr != USB_ENDPOINT_SYNC_ADAPTIVE))) {
408 
409 		/*
410 		 * In these modes the notion of sync_endpoint is irrelevant.
411 		 * Reset pointers to avoid using stale data from previously
412 		 * used settings, e.g. when configuration and endpoints were
413 		 * changed
414 		 */
415 
416 		subs->sync_endpoint = NULL;
417 		subs->data_endpoint->sync_master = NULL;
418 	}
419 
420 	err = set_sync_ep_implicit_fb_quirk(subs, dev, altsd, attr);
421 	if (err < 0)
422 		return err;
423 
424 	if (altsd->bNumEndpoints < 2)
425 		return 0;
426 
427 	if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
428 			     attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
429 	    (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
430 		return 0;
431 
432 	/*
433 	 * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
434 	 * if we don't find a sync endpoint, as on M-Audio Transit. In case of
435 	 * error fall back to SYNC mode and don't create sync endpoint
436 	 */
437 
438 	/* check sync-pipe endpoint */
439 	/* ... and check descriptor size before accessing bSynchAddress
440 	   because there is a version of the SB Audigy 2 NX firmware lacking
441 	   the audio fields in the endpoint descriptors */
442 	if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
443 	    (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
444 	     get_endpoint(alts, 1)->bSynchAddress != 0)) {
445 		dev_err(&dev->dev,
446 			"%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
447 			   fmt->iface, fmt->altsetting,
448 			   get_endpoint(alts, 1)->bmAttributes,
449 			   get_endpoint(alts, 1)->bLength,
450 			   get_endpoint(alts, 1)->bSynchAddress);
451 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
452 			return 0;
453 		return -EINVAL;
454 	}
455 	ep = get_endpoint(alts, 1)->bEndpointAddress;
456 	if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
457 	    ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
458 	     (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
459 		dev_err(&dev->dev,
460 			"%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
461 			   fmt->iface, fmt->altsetting,
462 			   is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
463 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
464 			return 0;
465 		return -EINVAL;
466 	}
467 
468 	implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
469 			== USB_ENDPOINT_USAGE_IMPLICIT_FB;
470 
471 	subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
472 						   alts, ep, !subs->direction,
473 						   implicit_fb ?
474 							SND_USB_ENDPOINT_TYPE_DATA :
475 							SND_USB_ENDPOINT_TYPE_SYNC);
476 	if (!subs->sync_endpoint) {
477 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
478 			return 0;
479 		return -EINVAL;
480 	}
481 
482 	subs->data_endpoint->sync_master = subs->sync_endpoint;
483 
484 	return 0;
485 }
486 
487 /*
488  * find a matching format and set up the interface
489  */
490 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
491 {
492 	struct usb_device *dev = subs->dev;
493 	struct usb_host_interface *alts;
494 	struct usb_interface_descriptor *altsd;
495 	struct usb_interface *iface;
496 	int err;
497 
498 	iface = usb_ifnum_to_if(dev, fmt->iface);
499 	if (WARN_ON(!iface))
500 		return -EINVAL;
501 	alts = &iface->altsetting[fmt->altset_idx];
502 	altsd = get_iface_desc(alts);
503 	if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
504 		return -EINVAL;
505 
506 	if (fmt == subs->cur_audiofmt)
507 		return 0;
508 
509 	/* close the old interface */
510 	if (subs->interface >= 0 && subs->interface != fmt->iface) {
511 		err = usb_set_interface(subs->dev, subs->interface, 0);
512 		if (err < 0) {
513 			dev_err(&dev->dev,
514 				"%d:%d: return to setting 0 failed (%d)\n",
515 				fmt->iface, fmt->altsetting, err);
516 			return -EIO;
517 		}
518 		subs->interface = -1;
519 		subs->altset_idx = 0;
520 	}
521 
522 	/* set interface */
523 	if (subs->interface != fmt->iface ||
524 	    subs->altset_idx != fmt->altset_idx) {
525 
526 		err = snd_usb_select_mode_quirk(subs, fmt);
527 		if (err < 0)
528 			return -EIO;
529 
530 		err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
531 		if (err < 0) {
532 			dev_err(&dev->dev,
533 				"%d:%d: usb_set_interface failed (%d)\n",
534 				fmt->iface, fmt->altsetting, err);
535 			return -EIO;
536 		}
537 		dev_dbg(&dev->dev, "setting usb interface %d:%d\n",
538 			fmt->iface, fmt->altsetting);
539 		subs->interface = fmt->iface;
540 		subs->altset_idx = fmt->altset_idx;
541 
542 		snd_usb_set_interface_quirk(dev);
543 	}
544 
545 	subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
546 						   alts, fmt->endpoint, subs->direction,
547 						   SND_USB_ENDPOINT_TYPE_DATA);
548 
549 	if (!subs->data_endpoint)
550 		return -EINVAL;
551 
552 	err = set_sync_endpoint(subs, fmt, dev, alts, altsd);
553 	if (err < 0)
554 		return err;
555 
556 	err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt);
557 	if (err < 0)
558 		return err;
559 
560 	subs->cur_audiofmt = fmt;
561 
562 	snd_usb_set_format_quirk(subs, fmt);
563 
564 	return 0;
565 }
566 
567 /*
568  * Return the score of matching two audioformats.
569  * Veto the audioformat if:
570  * - It has no channels for some reason.
571  * - Requested PCM format is not supported.
572  * - Requested sample rate is not supported.
573  */
574 static int match_endpoint_audioformats(struct snd_usb_substream *subs,
575 				       struct audioformat *fp,
576 				       struct audioformat *match, int rate,
577 				       snd_pcm_format_t pcm_format)
578 {
579 	int i;
580 	int score = 0;
581 
582 	if (fp->channels < 1) {
583 		dev_dbg(&subs->dev->dev,
584 			"%s: (fmt @%p) no channels\n", __func__, fp);
585 		return 0;
586 	}
587 
588 	if (!(fp->formats & pcm_format_to_bits(pcm_format))) {
589 		dev_dbg(&subs->dev->dev,
590 			"%s: (fmt @%p) no match for format %d\n", __func__,
591 			fp, pcm_format);
592 		return 0;
593 	}
594 
595 	for (i = 0; i < fp->nr_rates; i++) {
596 		if (fp->rate_table[i] == rate) {
597 			score++;
598 			break;
599 		}
600 	}
601 	if (!score) {
602 		dev_dbg(&subs->dev->dev,
603 			"%s: (fmt @%p) no match for rate %d\n", __func__,
604 			fp, rate);
605 		return 0;
606 	}
607 
608 	if (fp->channels == match->channels)
609 		score++;
610 
611 	dev_dbg(&subs->dev->dev,
612 		"%s: (fmt @%p) score %d\n", __func__, fp, score);
613 
614 	return score;
615 }
616 
617 /*
618  * Configure the sync ep using the rate and pcm format of the data ep.
619  */
620 static int configure_sync_endpoint(struct snd_usb_substream *subs)
621 {
622 	int ret;
623 	struct audioformat *fp;
624 	struct audioformat *sync_fp = NULL;
625 	int cur_score = 0;
626 	int sync_period_bytes = subs->period_bytes;
627 	struct snd_usb_substream *sync_subs =
628 		&subs->stream->substream[subs->direction ^ 1];
629 
630 	if (subs->sync_endpoint->type != SND_USB_ENDPOINT_TYPE_DATA ||
631 	    !subs->stream)
632 		return snd_usb_endpoint_set_params(subs->sync_endpoint,
633 						   subs->pcm_format,
634 						   subs->channels,
635 						   subs->period_bytes,
636 						   0, 0,
637 						   subs->cur_rate,
638 						   subs->cur_audiofmt,
639 						   NULL);
640 
641 	/* Try to find the best matching audioformat. */
642 	list_for_each_entry(fp, &sync_subs->fmt_list, list) {
643 		int score = match_endpoint_audioformats(subs,
644 							fp, subs->cur_audiofmt,
645 			subs->cur_rate, subs->pcm_format);
646 
647 		if (score > cur_score) {
648 			sync_fp = fp;
649 			cur_score = score;
650 		}
651 	}
652 
653 	if (unlikely(sync_fp == NULL)) {
654 		dev_err(&subs->dev->dev,
655 			"%s: no valid audioformat for sync ep %x found\n",
656 			__func__, sync_subs->ep_num);
657 		return -EINVAL;
658 	}
659 
660 	/*
661 	 * Recalculate the period bytes if channel number differ between
662 	 * data and sync ep audioformat.
663 	 */
664 	if (sync_fp->channels != subs->channels) {
665 		sync_period_bytes = (subs->period_bytes / subs->channels) *
666 			sync_fp->channels;
667 		dev_dbg(&subs->dev->dev,
668 			"%s: adjusted sync ep period bytes (%d -> %d)\n",
669 			__func__, subs->period_bytes, sync_period_bytes);
670 	}
671 
672 	ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
673 					  subs->pcm_format,
674 					  sync_fp->channels,
675 					  sync_period_bytes,
676 					  0, 0,
677 					  subs->cur_rate,
678 					  sync_fp,
679 					  NULL);
680 
681 	return ret;
682 }
683 
684 /*
685  * configure endpoint params
686  *
687  * called  during initial setup and upon resume
688  */
689 static int configure_endpoint(struct snd_usb_substream *subs)
690 {
691 	int ret;
692 
693 	/* format changed */
694 	stop_endpoints(subs, true);
695 	ret = snd_usb_endpoint_set_params(subs->data_endpoint,
696 					  subs->pcm_format,
697 					  subs->channels,
698 					  subs->period_bytes,
699 					  subs->period_frames,
700 					  subs->buffer_periods,
701 					  subs->cur_rate,
702 					  subs->cur_audiofmt,
703 					  subs->sync_endpoint);
704 	if (ret < 0)
705 		return ret;
706 
707 	if (subs->sync_endpoint)
708 		ret = configure_sync_endpoint(subs);
709 
710 	return ret;
711 }
712 
713 /*
714  * hw_params callback
715  *
716  * allocate a buffer and set the given audio format.
717  *
718  * so far we use a physically linear buffer although packetize transfer
719  * doesn't need a continuous area.
720  * if sg buffer is supported on the later version of alsa, we'll follow
721  * that.
722  */
723 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
724 			     struct snd_pcm_hw_params *hw_params)
725 {
726 	struct snd_usb_substream *subs = substream->runtime->private_data;
727 	struct audioformat *fmt;
728 	int ret;
729 
730 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
731 					       params_buffer_bytes(hw_params));
732 	if (ret < 0)
733 		return ret;
734 
735 	subs->pcm_format = params_format(hw_params);
736 	subs->period_bytes = params_period_bytes(hw_params);
737 	subs->period_frames = params_period_size(hw_params);
738 	subs->buffer_periods = params_periods(hw_params);
739 	subs->channels = params_channels(hw_params);
740 	subs->cur_rate = params_rate(hw_params);
741 
742 	fmt = find_format(subs);
743 	if (!fmt) {
744 		dev_dbg(&subs->dev->dev,
745 			"cannot set format: format = %#x, rate = %d, channels = %d\n",
746 			   subs->pcm_format, subs->cur_rate, subs->channels);
747 		return -EINVAL;
748 	}
749 
750 	ret = snd_usb_lock_shutdown(subs->stream->chip);
751 	if (ret < 0)
752 		return ret;
753 	ret = set_format(subs, fmt);
754 	snd_usb_unlock_shutdown(subs->stream->chip);
755 	if (ret < 0)
756 		return ret;
757 
758 	subs->interface = fmt->iface;
759 	subs->altset_idx = fmt->altset_idx;
760 	subs->need_setup_ep = true;
761 
762 	return 0;
763 }
764 
765 /*
766  * hw_free callback
767  *
768  * reset the audio format and release the buffer
769  */
770 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
771 {
772 	struct snd_usb_substream *subs = substream->runtime->private_data;
773 
774 	subs->cur_audiofmt = NULL;
775 	subs->cur_rate = 0;
776 	subs->period_bytes = 0;
777 	if (!snd_usb_lock_shutdown(subs->stream->chip)) {
778 		stop_endpoints(subs, true);
779 		snd_usb_endpoint_deactivate(subs->sync_endpoint);
780 		snd_usb_endpoint_deactivate(subs->data_endpoint);
781 		snd_usb_unlock_shutdown(subs->stream->chip);
782 	}
783 	return snd_pcm_lib_free_vmalloc_buffer(substream);
784 }
785 
786 /*
787  * prepare callback
788  *
789  * only a few subtle things...
790  */
791 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
792 {
793 	struct snd_pcm_runtime *runtime = substream->runtime;
794 	struct snd_usb_substream *subs = runtime->private_data;
795 	struct usb_host_interface *alts;
796 	struct usb_interface *iface;
797 	int ret;
798 
799 	if (! subs->cur_audiofmt) {
800 		dev_err(&subs->dev->dev, "no format is specified!\n");
801 		return -ENXIO;
802 	}
803 
804 	ret = snd_usb_lock_shutdown(subs->stream->chip);
805 	if (ret < 0)
806 		return ret;
807 	if (snd_BUG_ON(!subs->data_endpoint)) {
808 		ret = -EIO;
809 		goto unlock;
810 	}
811 
812 	snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
813 	snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
814 
815 	ret = set_format(subs, subs->cur_audiofmt);
816 	if (ret < 0)
817 		goto unlock;
818 
819 	if (subs->need_setup_ep) {
820 
821 		iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
822 		alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
823 		ret = snd_usb_init_sample_rate(subs->stream->chip,
824 					       subs->cur_audiofmt->iface,
825 					       alts,
826 					       subs->cur_audiofmt,
827 					       subs->cur_rate);
828 		if (ret < 0)
829 			goto unlock;
830 
831 		ret = configure_endpoint(subs);
832 		if (ret < 0)
833 			goto unlock;
834 		subs->need_setup_ep = false;
835 	}
836 
837 	/* some unit conversions in runtime */
838 	subs->data_endpoint->maxframesize =
839 		bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
840 	subs->data_endpoint->curframesize =
841 		bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
842 
843 	/* reset the pointer */
844 	subs->hwptr_done = 0;
845 	subs->transfer_done = 0;
846 	subs->last_delay = 0;
847 	subs->last_frame_number = 0;
848 	runtime->delay = 0;
849 
850 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
851 	 * updates for all URBs would happen at the same time when starting */
852 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
853 		ret = start_endpoints(subs);
854 
855  unlock:
856 	snd_usb_unlock_shutdown(subs->stream->chip);
857 	return ret;
858 }
859 
860 static const struct snd_pcm_hardware snd_usb_hardware =
861 {
862 	.info =			SNDRV_PCM_INFO_MMAP |
863 				SNDRV_PCM_INFO_MMAP_VALID |
864 				SNDRV_PCM_INFO_BATCH |
865 				SNDRV_PCM_INFO_INTERLEAVED |
866 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
867 				SNDRV_PCM_INFO_PAUSE,
868 	.buffer_bytes_max =	1024 * 1024,
869 	.period_bytes_min =	64,
870 	.period_bytes_max =	512 * 1024,
871 	.periods_min =		2,
872 	.periods_max =		1024,
873 };
874 
875 static int hw_check_valid_format(struct snd_usb_substream *subs,
876 				 struct snd_pcm_hw_params *params,
877 				 struct audioformat *fp)
878 {
879 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
880 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
881 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
882 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
883 	struct snd_mask check_fmts;
884 	unsigned int ptime;
885 
886 	/* check the format */
887 	snd_mask_none(&check_fmts);
888 	check_fmts.bits[0] = (u32)fp->formats;
889 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
890 	snd_mask_intersect(&check_fmts, fmts);
891 	if (snd_mask_empty(&check_fmts)) {
892 		hwc_debug("   > check: no supported format %d\n", fp->format);
893 		return 0;
894 	}
895 	/* check the channels */
896 	if (fp->channels < ct->min || fp->channels > ct->max) {
897 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
898 		return 0;
899 	}
900 	/* check the rate is within the range */
901 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
902 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
903 		return 0;
904 	}
905 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
906 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
907 		return 0;
908 	}
909 	/* check whether the period time is >= the data packet interval */
910 	if (subs->speed != USB_SPEED_FULL) {
911 		ptime = 125 * (1 << fp->datainterval);
912 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
913 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
914 			return 0;
915 		}
916 	}
917 	return 1;
918 }
919 
920 static int hw_rule_rate(struct snd_pcm_hw_params *params,
921 			struct snd_pcm_hw_rule *rule)
922 {
923 	struct snd_usb_substream *subs = rule->private;
924 	struct audioformat *fp;
925 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
926 	unsigned int rmin, rmax;
927 	int changed;
928 
929 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
930 	changed = 0;
931 	rmin = rmax = 0;
932 	list_for_each_entry(fp, &subs->fmt_list, list) {
933 		if (!hw_check_valid_format(subs, params, fp))
934 			continue;
935 		if (changed++) {
936 			if (rmin > fp->rate_min)
937 				rmin = fp->rate_min;
938 			if (rmax < fp->rate_max)
939 				rmax = fp->rate_max;
940 		} else {
941 			rmin = fp->rate_min;
942 			rmax = fp->rate_max;
943 		}
944 	}
945 
946 	if (!changed) {
947 		hwc_debug("  --> get empty\n");
948 		it->empty = 1;
949 		return -EINVAL;
950 	}
951 
952 	changed = 0;
953 	if (it->min < rmin) {
954 		it->min = rmin;
955 		it->openmin = 0;
956 		changed = 1;
957 	}
958 	if (it->max > rmax) {
959 		it->max = rmax;
960 		it->openmax = 0;
961 		changed = 1;
962 	}
963 	if (snd_interval_checkempty(it)) {
964 		it->empty = 1;
965 		return -EINVAL;
966 	}
967 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
968 	return changed;
969 }
970 
971 
972 static int hw_rule_channels(struct snd_pcm_hw_params *params,
973 			    struct snd_pcm_hw_rule *rule)
974 {
975 	struct snd_usb_substream *subs = rule->private;
976 	struct audioformat *fp;
977 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
978 	unsigned int rmin, rmax;
979 	int changed;
980 
981 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
982 	changed = 0;
983 	rmin = rmax = 0;
984 	list_for_each_entry(fp, &subs->fmt_list, list) {
985 		if (!hw_check_valid_format(subs, params, fp))
986 			continue;
987 		if (changed++) {
988 			if (rmin > fp->channels)
989 				rmin = fp->channels;
990 			if (rmax < fp->channels)
991 				rmax = fp->channels;
992 		} else {
993 			rmin = fp->channels;
994 			rmax = fp->channels;
995 		}
996 	}
997 
998 	if (!changed) {
999 		hwc_debug("  --> get empty\n");
1000 		it->empty = 1;
1001 		return -EINVAL;
1002 	}
1003 
1004 	changed = 0;
1005 	if (it->min < rmin) {
1006 		it->min = rmin;
1007 		it->openmin = 0;
1008 		changed = 1;
1009 	}
1010 	if (it->max > rmax) {
1011 		it->max = rmax;
1012 		it->openmax = 0;
1013 		changed = 1;
1014 	}
1015 	if (snd_interval_checkempty(it)) {
1016 		it->empty = 1;
1017 		return -EINVAL;
1018 	}
1019 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1020 	return changed;
1021 }
1022 
1023 static int hw_rule_format(struct snd_pcm_hw_params *params,
1024 			  struct snd_pcm_hw_rule *rule)
1025 {
1026 	struct snd_usb_substream *subs = rule->private;
1027 	struct audioformat *fp;
1028 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
1029 	u64 fbits;
1030 	u32 oldbits[2];
1031 	int changed;
1032 
1033 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
1034 	fbits = 0;
1035 	list_for_each_entry(fp, &subs->fmt_list, list) {
1036 		if (!hw_check_valid_format(subs, params, fp))
1037 			continue;
1038 		fbits |= fp->formats;
1039 	}
1040 
1041 	oldbits[0] = fmt->bits[0];
1042 	oldbits[1] = fmt->bits[1];
1043 	fmt->bits[0] &= (u32)fbits;
1044 	fmt->bits[1] &= (u32)(fbits >> 32);
1045 	if (!fmt->bits[0] && !fmt->bits[1]) {
1046 		hwc_debug("  --> get empty\n");
1047 		return -EINVAL;
1048 	}
1049 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
1050 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
1051 	return changed;
1052 }
1053 
1054 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
1055 			       struct snd_pcm_hw_rule *rule)
1056 {
1057 	struct snd_usb_substream *subs = rule->private;
1058 	struct audioformat *fp;
1059 	struct snd_interval *it;
1060 	unsigned char min_datainterval;
1061 	unsigned int pmin;
1062 	int changed;
1063 
1064 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
1065 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
1066 	min_datainterval = 0xff;
1067 	list_for_each_entry(fp, &subs->fmt_list, list) {
1068 		if (!hw_check_valid_format(subs, params, fp))
1069 			continue;
1070 		min_datainterval = min(min_datainterval, fp->datainterval);
1071 	}
1072 	if (min_datainterval == 0xff) {
1073 		hwc_debug("  --> get empty\n");
1074 		it->empty = 1;
1075 		return -EINVAL;
1076 	}
1077 	pmin = 125 * (1 << min_datainterval);
1078 	changed = 0;
1079 	if (it->min < pmin) {
1080 		it->min = pmin;
1081 		it->openmin = 0;
1082 		changed = 1;
1083 	}
1084 	if (snd_interval_checkempty(it)) {
1085 		it->empty = 1;
1086 		return -EINVAL;
1087 	}
1088 	hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
1089 	return changed;
1090 }
1091 
1092 /*
1093  *  If the device supports unusual bit rates, does the request meet these?
1094  */
1095 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
1096 				  struct snd_usb_substream *subs)
1097 {
1098 	struct audioformat *fp;
1099 	int *rate_list;
1100 	int count = 0, needs_knot = 0;
1101 	int err;
1102 
1103 	kfree(subs->rate_list.list);
1104 	subs->rate_list.list = NULL;
1105 
1106 	list_for_each_entry(fp, &subs->fmt_list, list) {
1107 		if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
1108 			return 0;
1109 		count += fp->nr_rates;
1110 		if (fp->rates & SNDRV_PCM_RATE_KNOT)
1111 			needs_knot = 1;
1112 	}
1113 	if (!needs_knot)
1114 		return 0;
1115 
1116 	subs->rate_list.list = rate_list =
1117 		kmalloc(sizeof(int) * count, GFP_KERNEL);
1118 	if (!subs->rate_list.list)
1119 		return -ENOMEM;
1120 	subs->rate_list.count = count;
1121 	subs->rate_list.mask = 0;
1122 	count = 0;
1123 	list_for_each_entry(fp, &subs->fmt_list, list) {
1124 		int i;
1125 		for (i = 0; i < fp->nr_rates; i++)
1126 			rate_list[count++] = fp->rate_table[i];
1127 	}
1128 	err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1129 					 &subs->rate_list);
1130 	if (err < 0)
1131 		return err;
1132 
1133 	return 0;
1134 }
1135 
1136 
1137 /*
1138  * set up the runtime hardware information.
1139  */
1140 
1141 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1142 {
1143 	struct audioformat *fp;
1144 	unsigned int pt, ptmin;
1145 	int param_period_time_if_needed;
1146 	int err;
1147 
1148 	runtime->hw.formats = subs->formats;
1149 
1150 	runtime->hw.rate_min = 0x7fffffff;
1151 	runtime->hw.rate_max = 0;
1152 	runtime->hw.channels_min = 256;
1153 	runtime->hw.channels_max = 0;
1154 	runtime->hw.rates = 0;
1155 	ptmin = UINT_MAX;
1156 	/* check min/max rates and channels */
1157 	list_for_each_entry(fp, &subs->fmt_list, list) {
1158 		runtime->hw.rates |= fp->rates;
1159 		if (runtime->hw.rate_min > fp->rate_min)
1160 			runtime->hw.rate_min = fp->rate_min;
1161 		if (runtime->hw.rate_max < fp->rate_max)
1162 			runtime->hw.rate_max = fp->rate_max;
1163 		if (runtime->hw.channels_min > fp->channels)
1164 			runtime->hw.channels_min = fp->channels;
1165 		if (runtime->hw.channels_max < fp->channels)
1166 			runtime->hw.channels_max = fp->channels;
1167 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1168 			/* FIXME: there might be more than one audio formats... */
1169 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1170 				fp->frame_size;
1171 		}
1172 		pt = 125 * (1 << fp->datainterval);
1173 		ptmin = min(ptmin, pt);
1174 	}
1175 	err = snd_usb_autoresume(subs->stream->chip);
1176 	if (err < 0)
1177 		return err;
1178 
1179 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1180 	if (subs->speed == USB_SPEED_FULL)
1181 		/* full speed devices have fixed data packet interval */
1182 		ptmin = 1000;
1183 	if (ptmin == 1000)
1184 		/* if period time doesn't go below 1 ms, no rules needed */
1185 		param_period_time_if_needed = -1;
1186 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1187 				     ptmin, UINT_MAX);
1188 
1189 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1190 				       hw_rule_rate, subs,
1191 				       SNDRV_PCM_HW_PARAM_FORMAT,
1192 				       SNDRV_PCM_HW_PARAM_CHANNELS,
1193 				       param_period_time_if_needed,
1194 				       -1)) < 0)
1195 		goto rep_err;
1196 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1197 				       hw_rule_channels, subs,
1198 				       SNDRV_PCM_HW_PARAM_FORMAT,
1199 				       SNDRV_PCM_HW_PARAM_RATE,
1200 				       param_period_time_if_needed,
1201 				       -1)) < 0)
1202 		goto rep_err;
1203 	if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1204 				       hw_rule_format, subs,
1205 				       SNDRV_PCM_HW_PARAM_RATE,
1206 				       SNDRV_PCM_HW_PARAM_CHANNELS,
1207 				       param_period_time_if_needed,
1208 				       -1)) < 0)
1209 		goto rep_err;
1210 	if (param_period_time_if_needed >= 0) {
1211 		err = snd_pcm_hw_rule_add(runtime, 0,
1212 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1213 					  hw_rule_period_time, subs,
1214 					  SNDRV_PCM_HW_PARAM_FORMAT,
1215 					  SNDRV_PCM_HW_PARAM_CHANNELS,
1216 					  SNDRV_PCM_HW_PARAM_RATE,
1217 					  -1);
1218 		if (err < 0)
1219 			goto rep_err;
1220 	}
1221 	if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
1222 		goto rep_err;
1223 	return 0;
1224 
1225 rep_err:
1226 	snd_usb_autosuspend(subs->stream->chip);
1227 	return err;
1228 }
1229 
1230 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
1231 {
1232 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1233 	struct snd_pcm_runtime *runtime = substream->runtime;
1234 	struct snd_usb_substream *subs = &as->substream[direction];
1235 
1236 	subs->interface = -1;
1237 	subs->altset_idx = 0;
1238 	runtime->hw = snd_usb_hardware;
1239 	runtime->private_data = subs;
1240 	subs->pcm_substream = substream;
1241 	/* runtime PM is also done there */
1242 
1243 	/* initialize DSD/DOP context */
1244 	subs->dsd_dop.byte_idx = 0;
1245 	subs->dsd_dop.channel = 0;
1246 	subs->dsd_dop.marker = 1;
1247 
1248 	return setup_hw_info(runtime, subs);
1249 }
1250 
1251 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
1252 {
1253 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1254 	struct snd_usb_substream *subs = &as->substream[direction];
1255 
1256 	stop_endpoints(subs, true);
1257 
1258 	if (subs->interface >= 0 &&
1259 	    !snd_usb_lock_shutdown(subs->stream->chip)) {
1260 		usb_set_interface(subs->dev, subs->interface, 0);
1261 		subs->interface = -1;
1262 		snd_usb_unlock_shutdown(subs->stream->chip);
1263 	}
1264 
1265 	subs->pcm_substream = NULL;
1266 	snd_usb_autosuspend(subs->stream->chip);
1267 
1268 	return 0;
1269 }
1270 
1271 /* Since a URB can handle only a single linear buffer, we must use double
1272  * buffering when the data to be transferred overflows the buffer boundary.
1273  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1274  * for all URBs.
1275  */
1276 static void retire_capture_urb(struct snd_usb_substream *subs,
1277 			       struct urb *urb)
1278 {
1279 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1280 	unsigned int stride, frames, bytes, oldptr;
1281 	int i, period_elapsed = 0;
1282 	unsigned long flags;
1283 	unsigned char *cp;
1284 	int current_frame_number;
1285 
1286 	/* read frame number here, update pointer in critical section */
1287 	current_frame_number = usb_get_current_frame_number(subs->dev);
1288 
1289 	stride = runtime->frame_bits >> 3;
1290 
1291 	for (i = 0; i < urb->number_of_packets; i++) {
1292 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1293 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1294 			dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1295 				i, urb->iso_frame_desc[i].status);
1296 			// continue;
1297 		}
1298 		bytes = urb->iso_frame_desc[i].actual_length;
1299 		frames = bytes / stride;
1300 		if (!subs->txfr_quirk)
1301 			bytes = frames * stride;
1302 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1303 			int oldbytes = bytes;
1304 			bytes = frames * stride;
1305 			dev_warn(&subs->dev->dev,
1306 				 "Corrected urb data len. %d->%d\n",
1307 							oldbytes, bytes);
1308 		}
1309 		/* update the current pointer */
1310 		spin_lock_irqsave(&subs->lock, flags);
1311 		oldptr = subs->hwptr_done;
1312 		subs->hwptr_done += bytes;
1313 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1314 			subs->hwptr_done -= runtime->buffer_size * stride;
1315 		frames = (bytes + (oldptr % stride)) / stride;
1316 		subs->transfer_done += frames;
1317 		if (subs->transfer_done >= runtime->period_size) {
1318 			subs->transfer_done -= runtime->period_size;
1319 			period_elapsed = 1;
1320 		}
1321 		/* capture delay is by construction limited to one URB,
1322 		 * reset delays here
1323 		 */
1324 		runtime->delay = subs->last_delay = 0;
1325 
1326 		/* realign last_frame_number */
1327 		subs->last_frame_number = current_frame_number;
1328 		subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1329 
1330 		spin_unlock_irqrestore(&subs->lock, flags);
1331 		/* copy a data chunk */
1332 		if (oldptr + bytes > runtime->buffer_size * stride) {
1333 			unsigned int bytes1 =
1334 					runtime->buffer_size * stride - oldptr;
1335 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1336 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1337 		} else {
1338 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1339 		}
1340 	}
1341 
1342 	if (period_elapsed)
1343 		snd_pcm_period_elapsed(subs->pcm_substream);
1344 }
1345 
1346 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1347 					     struct urb *urb, unsigned int bytes)
1348 {
1349 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1350 	unsigned int stride = runtime->frame_bits >> 3;
1351 	unsigned int dst_idx = 0;
1352 	unsigned int src_idx = subs->hwptr_done;
1353 	unsigned int wrap = runtime->buffer_size * stride;
1354 	u8 *dst = urb->transfer_buffer;
1355 	u8 *src = runtime->dma_area;
1356 	u8 marker[] = { 0x05, 0xfa };
1357 
1358 	/*
1359 	 * The DSP DOP format defines a way to transport DSD samples over
1360 	 * normal PCM data endpoints. It requires stuffing of marker bytes
1361 	 * (0x05 and 0xfa, alternating per sample frame), and then expects
1362 	 * 2 additional bytes of actual payload. The whole frame is stored
1363 	 * LSB.
1364 	 *
1365 	 * Hence, for a stereo transport, the buffer layout looks like this,
1366 	 * where L refers to left channel samples and R to right.
1367 	 *
1368 	 *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1369 	 *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1370 	 *   .....
1371 	 *
1372 	 */
1373 
1374 	while (bytes--) {
1375 		if (++subs->dsd_dop.byte_idx == 3) {
1376 			/* frame boundary? */
1377 			dst[dst_idx++] = marker[subs->dsd_dop.marker];
1378 			src_idx += 2;
1379 			subs->dsd_dop.byte_idx = 0;
1380 
1381 			if (++subs->dsd_dop.channel % runtime->channels == 0) {
1382 				/* alternate the marker */
1383 				subs->dsd_dop.marker++;
1384 				subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1385 				subs->dsd_dop.channel = 0;
1386 			}
1387 		} else {
1388 			/* stuff the DSD payload */
1389 			int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1390 
1391 			if (subs->cur_audiofmt->dsd_bitrev)
1392 				dst[dst_idx++] = bitrev8(src[idx]);
1393 			else
1394 				dst[dst_idx++] = src[idx];
1395 
1396 			subs->hwptr_done++;
1397 		}
1398 	}
1399 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1400 		subs->hwptr_done -= runtime->buffer_size * stride;
1401 }
1402 
1403 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1404 			int offset, int stride, unsigned int bytes)
1405 {
1406 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1407 
1408 	if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1409 		/* err, the transferred area goes over buffer boundary. */
1410 		unsigned int bytes1 =
1411 			runtime->buffer_size * stride - subs->hwptr_done;
1412 		memcpy(urb->transfer_buffer + offset,
1413 		       runtime->dma_area + subs->hwptr_done, bytes1);
1414 		memcpy(urb->transfer_buffer + offset + bytes1,
1415 		       runtime->dma_area, bytes - bytes1);
1416 	} else {
1417 		memcpy(urb->transfer_buffer + offset,
1418 		       runtime->dma_area + subs->hwptr_done, bytes);
1419 	}
1420 	subs->hwptr_done += bytes;
1421 	if (subs->hwptr_done >= runtime->buffer_size * stride)
1422 		subs->hwptr_done -= runtime->buffer_size * stride;
1423 }
1424 
1425 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1426 				      struct urb *urb, int stride,
1427 				      unsigned int bytes)
1428 {
1429 	__le32 packet_length;
1430 	int i;
1431 
1432 	/* Put __le32 length descriptor at start of each packet. */
1433 	for (i = 0; i < urb->number_of_packets; i++) {
1434 		unsigned int length = urb->iso_frame_desc[i].length;
1435 		unsigned int offset = urb->iso_frame_desc[i].offset;
1436 
1437 		packet_length = cpu_to_le32(length);
1438 		offset += i * sizeof(packet_length);
1439 		urb->iso_frame_desc[i].offset = offset;
1440 		urb->iso_frame_desc[i].length += sizeof(packet_length);
1441 		memcpy(urb->transfer_buffer + offset,
1442 		       &packet_length, sizeof(packet_length));
1443 		copy_to_urb(subs, urb, offset + sizeof(packet_length),
1444 			    stride, length);
1445 	}
1446 	/* Adjust transfer size accordingly. */
1447 	bytes += urb->number_of_packets * sizeof(packet_length);
1448 	return bytes;
1449 }
1450 
1451 static void prepare_playback_urb(struct snd_usb_substream *subs,
1452 				 struct urb *urb)
1453 {
1454 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1455 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1456 	struct snd_urb_ctx *ctx = urb->context;
1457 	unsigned int counts, frames, bytes;
1458 	int i, stride, period_elapsed = 0;
1459 	unsigned long flags;
1460 
1461 	stride = runtime->frame_bits >> 3;
1462 
1463 	frames = 0;
1464 	urb->number_of_packets = 0;
1465 	spin_lock_irqsave(&subs->lock, flags);
1466 	subs->frame_limit += ep->max_urb_frames;
1467 	for (i = 0; i < ctx->packets; i++) {
1468 		if (ctx->packet_size[i])
1469 			counts = ctx->packet_size[i];
1470 		else
1471 			counts = snd_usb_endpoint_next_packet_size(ep);
1472 
1473 		/* set up descriptor */
1474 		urb->iso_frame_desc[i].offset = frames * ep->stride;
1475 		urb->iso_frame_desc[i].length = counts * ep->stride;
1476 		frames += counts;
1477 		urb->number_of_packets++;
1478 		subs->transfer_done += counts;
1479 		if (subs->transfer_done >= runtime->period_size) {
1480 			subs->transfer_done -= runtime->period_size;
1481 			subs->frame_limit = 0;
1482 			period_elapsed = 1;
1483 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1484 				if (subs->transfer_done > 0) {
1485 					/* FIXME: fill-max mode is not
1486 					 * supported yet */
1487 					frames -= subs->transfer_done;
1488 					counts -= subs->transfer_done;
1489 					urb->iso_frame_desc[i].length =
1490 						counts * ep->stride;
1491 					subs->transfer_done = 0;
1492 				}
1493 				i++;
1494 				if (i < ctx->packets) {
1495 					/* add a transfer delimiter */
1496 					urb->iso_frame_desc[i].offset =
1497 						frames * ep->stride;
1498 					urb->iso_frame_desc[i].length = 0;
1499 					urb->number_of_packets++;
1500 				}
1501 				break;
1502 			}
1503 		}
1504 		/* finish at the period boundary or after enough frames */
1505 		if ((period_elapsed ||
1506 				subs->transfer_done >= subs->frame_limit) &&
1507 		    !snd_usb_endpoint_implicit_feedback_sink(ep))
1508 			break;
1509 	}
1510 	bytes = frames * ep->stride;
1511 
1512 	if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1513 		     subs->cur_audiofmt->dsd_dop)) {
1514 		fill_playback_urb_dsd_dop(subs, urb, bytes);
1515 	} else if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1516 			   subs->cur_audiofmt->dsd_bitrev)) {
1517 		/* bit-reverse the bytes */
1518 		u8 *buf = urb->transfer_buffer;
1519 		for (i = 0; i < bytes; i++) {
1520 			int idx = (subs->hwptr_done + i)
1521 				% (runtime->buffer_size * stride);
1522 			buf[i] = bitrev8(runtime->dma_area[idx]);
1523 		}
1524 
1525 		subs->hwptr_done += bytes;
1526 		if (subs->hwptr_done >= runtime->buffer_size * stride)
1527 			subs->hwptr_done -= runtime->buffer_size * stride;
1528 	} else {
1529 		/* usual PCM */
1530 		if (!subs->tx_length_quirk)
1531 			copy_to_urb(subs, urb, 0, stride, bytes);
1532 		else
1533 			bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1534 			/* bytes is now amount of outgoing data */
1535 	}
1536 
1537 	/* update delay with exact number of samples queued */
1538 	runtime->delay = subs->last_delay;
1539 	runtime->delay += frames;
1540 	subs->last_delay = runtime->delay;
1541 
1542 	/* realign last_frame_number */
1543 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1544 	subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1545 
1546 	if (subs->trigger_tstamp_pending_update) {
1547 		/* this is the first actual URB submitted,
1548 		 * update trigger timestamp to reflect actual start time
1549 		 */
1550 		snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1551 		subs->trigger_tstamp_pending_update = false;
1552 	}
1553 
1554 	spin_unlock_irqrestore(&subs->lock, flags);
1555 	urb->transfer_buffer_length = bytes;
1556 	if (period_elapsed)
1557 		snd_pcm_period_elapsed(subs->pcm_substream);
1558 }
1559 
1560 /*
1561  * process after playback data complete
1562  * - decrease the delay count again
1563  */
1564 static void retire_playback_urb(struct snd_usb_substream *subs,
1565 			       struct urb *urb)
1566 {
1567 	unsigned long flags;
1568 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1569 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1570 	int processed = urb->transfer_buffer_length / ep->stride;
1571 	int est_delay;
1572 
1573 	/* ignore the delay accounting when procssed=0 is given, i.e.
1574 	 * silent payloads are procssed before handling the actual data
1575 	 */
1576 	if (!processed)
1577 		return;
1578 
1579 	spin_lock_irqsave(&subs->lock, flags);
1580 	if (!subs->last_delay)
1581 		goto out; /* short path */
1582 
1583 	est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1584 	/* update delay with exact number of samples played */
1585 	if (processed > subs->last_delay)
1586 		subs->last_delay = 0;
1587 	else
1588 		subs->last_delay -= processed;
1589 	runtime->delay = subs->last_delay;
1590 
1591 	/*
1592 	 * Report when delay estimate is off by more than 2ms.
1593 	 * The error should be lower than 2ms since the estimate relies
1594 	 * on two reads of a counter updated every ms.
1595 	 */
1596 	if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1597 		dev_dbg_ratelimited(&subs->dev->dev,
1598 			"delay: estimated %d, actual %d\n",
1599 			est_delay, subs->last_delay);
1600 
1601 	if (!subs->running) {
1602 		/* update last_frame_number for delay counting here since
1603 		 * prepare_playback_urb won't be called during pause
1604 		 */
1605 		subs->last_frame_number =
1606 			usb_get_current_frame_number(subs->dev) & 0xff;
1607 	}
1608 
1609  out:
1610 	spin_unlock_irqrestore(&subs->lock, flags);
1611 }
1612 
1613 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1614 {
1615 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1616 }
1617 
1618 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1619 {
1620 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1621 }
1622 
1623 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1624 {
1625 	return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1626 }
1627 
1628 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1629 {
1630 	return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1631 }
1632 
1633 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1634 					      int cmd)
1635 {
1636 	struct snd_usb_substream *subs = substream->runtime->private_data;
1637 
1638 	switch (cmd) {
1639 	case SNDRV_PCM_TRIGGER_START:
1640 		subs->trigger_tstamp_pending_update = true;
1641 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1642 		subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1643 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1644 		subs->running = 1;
1645 		return 0;
1646 	case SNDRV_PCM_TRIGGER_STOP:
1647 		stop_endpoints(subs, false);
1648 		subs->running = 0;
1649 		return 0;
1650 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1651 		subs->data_endpoint->prepare_data_urb = NULL;
1652 		/* keep retire_data_urb for delay calculation */
1653 		subs->data_endpoint->retire_data_urb = retire_playback_urb;
1654 		subs->running = 0;
1655 		return 0;
1656 	}
1657 
1658 	return -EINVAL;
1659 }
1660 
1661 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1662 					     int cmd)
1663 {
1664 	int err;
1665 	struct snd_usb_substream *subs = substream->runtime->private_data;
1666 
1667 	switch (cmd) {
1668 	case SNDRV_PCM_TRIGGER_START:
1669 		err = start_endpoints(subs);
1670 		if (err < 0)
1671 			return err;
1672 
1673 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1674 		subs->running = 1;
1675 		return 0;
1676 	case SNDRV_PCM_TRIGGER_STOP:
1677 		stop_endpoints(subs, false);
1678 		subs->running = 0;
1679 		return 0;
1680 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1681 		subs->data_endpoint->retire_data_urb = NULL;
1682 		subs->running = 0;
1683 		return 0;
1684 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1685 		subs->data_endpoint->retire_data_urb = retire_capture_urb;
1686 		subs->running = 1;
1687 		return 0;
1688 	}
1689 
1690 	return -EINVAL;
1691 }
1692 
1693 static const struct snd_pcm_ops snd_usb_playback_ops = {
1694 	.open =		snd_usb_playback_open,
1695 	.close =	snd_usb_playback_close,
1696 	.ioctl =	snd_pcm_lib_ioctl,
1697 	.hw_params =	snd_usb_hw_params,
1698 	.hw_free =	snd_usb_hw_free,
1699 	.prepare =	snd_usb_pcm_prepare,
1700 	.trigger =	snd_usb_substream_playback_trigger,
1701 	.pointer =	snd_usb_pcm_pointer,
1702 	.page =		snd_pcm_lib_get_vmalloc_page,
1703 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1704 };
1705 
1706 static const struct snd_pcm_ops snd_usb_capture_ops = {
1707 	.open =		snd_usb_capture_open,
1708 	.close =	snd_usb_capture_close,
1709 	.ioctl =	snd_pcm_lib_ioctl,
1710 	.hw_params =	snd_usb_hw_params,
1711 	.hw_free =	snd_usb_hw_free,
1712 	.prepare =	snd_usb_pcm_prepare,
1713 	.trigger =	snd_usb_substream_capture_trigger,
1714 	.pointer =	snd_usb_pcm_pointer,
1715 	.page =		snd_pcm_lib_get_vmalloc_page,
1716 	.mmap =		snd_pcm_lib_mmap_vmalloc,
1717 };
1718 
1719 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1720 {
1721 	snd_pcm_set_ops(pcm, stream,
1722 			stream == SNDRV_PCM_STREAM_PLAYBACK ?
1723 			&snd_usb_playback_ops : &snd_usb_capture_ops);
1724 }
1725