48afae053c56f9ff75b72aa83a73a7d1ab267565
[kvmfornfv.git] / pcm.c
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         }
352         if (attr == USB_ENDPOINT_SYNC_ASYNC &&
353             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
354             altsd->bInterfaceProtocol == 2 &&
355             altsd->bNumEndpoints == 1 &&
356             USB_ID_VENDOR(subs->stream->chip->usb_id) == 0x0582 /* Roland */ &&
357             search_roland_implicit_fb(dev, altsd->bInterfaceNumber + 1,
358                                       altsd->bAlternateSetting,
359                                       &alts, &ep) >= 0) {
360                 goto add_sync_ep;
361         }
362
363         /* No quirk */
364         return 0;
365
366 add_sync_ep:
367         subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
368                                                    alts, ep, !subs->direction,
369                                                    SND_USB_ENDPOINT_TYPE_DATA);
370         if (!subs->sync_endpoint)
371                 return -EINVAL;
372
373         subs->data_endpoint->sync_master = subs->sync_endpoint;
374
375         return 0;
376 }
377
378 static int set_sync_endpoint(struct snd_usb_substream *subs,
379                              struct audioformat *fmt,
380                              struct usb_device *dev,
381                              struct usb_host_interface *alts,
382                              struct usb_interface_descriptor *altsd)
383 {
384         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
385         unsigned int ep, attr;
386         bool implicit_fb;
387         int err;
388
389         /* we need a sync pipe in async OUT or adaptive IN mode */
390         /* check the number of EP, since some devices have broken
391          * descriptors which fool us.  if it has only one EP,
392          * assume it as adaptive-out or sync-in.
393          */
394         attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
395
396         if ((is_playback && (attr != USB_ENDPOINT_SYNC_ASYNC)) ||
397                 (!is_playback && (attr != USB_ENDPOINT_SYNC_ADAPTIVE))) {
398
399                 /*
400                  * In these modes the notion of sync_endpoint is irrelevant.
401                  * Reset pointers to avoid using stale data from previously
402                  * used settings, e.g. when configuration and endpoints were
403                  * changed
404                  */
405
406                 subs->sync_endpoint = NULL;
407                 subs->data_endpoint->sync_master = NULL;
408         }
409
410         err = set_sync_ep_implicit_fb_quirk(subs, dev, altsd, attr);
411         if (err < 0)
412                 return err;
413
414         if (altsd->bNumEndpoints < 2)
415                 return 0;
416
417         if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
418                              attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
419             (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
420                 return 0;
421
422         /*
423          * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
424          * if we don't find a sync endpoint, as on M-Audio Transit. In case of
425          * error fall back to SYNC mode and don't create sync endpoint
426          */
427
428         /* check sync-pipe endpoint */
429         /* ... and check descriptor size before accessing bSynchAddress
430            because there is a version of the SB Audigy 2 NX firmware lacking
431            the audio fields in the endpoint descriptors */
432         if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
433             (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
434              get_endpoint(alts, 1)->bSynchAddress != 0)) {
435                 dev_err(&dev->dev,
436                         "%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
437                            fmt->iface, fmt->altsetting,
438                            get_endpoint(alts, 1)->bmAttributes,
439                            get_endpoint(alts, 1)->bLength,
440                            get_endpoint(alts, 1)->bSynchAddress);
441                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
442                         return 0;
443                 return -EINVAL;
444         }
445         ep = get_endpoint(alts, 1)->bEndpointAddress;
446         if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
447             ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
448              (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
449                 dev_err(&dev->dev,
450                         "%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
451                            fmt->iface, fmt->altsetting,
452                            is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
453                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
454                         return 0;
455                 return -EINVAL;
456         }
457
458         implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
459                         == USB_ENDPOINT_USAGE_IMPLICIT_FB;
460
461         subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
462                                                    alts, ep, !subs->direction,
463                                                    implicit_fb ?
464                                                         SND_USB_ENDPOINT_TYPE_DATA :
465                                                         SND_USB_ENDPOINT_TYPE_SYNC);
466         if (!subs->sync_endpoint) {
467                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
468                         return 0;
469                 return -EINVAL;
470         }
471
472         subs->data_endpoint->sync_master = subs->sync_endpoint;
473
474         return 0;
475 }
476
477 /*
478  * find a matching format and set up the interface
479  */
480 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
481 {
482         struct usb_device *dev = subs->dev;
483         struct usb_host_interface *alts;
484         struct usb_interface_descriptor *altsd;
485         struct usb_interface *iface;
486         int err;
487
488         iface = usb_ifnum_to_if(dev, fmt->iface);
489         if (WARN_ON(!iface))
490                 return -EINVAL;
491         alts = &iface->altsetting[fmt->altset_idx];
492         altsd = get_iface_desc(alts);
493         if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
494                 return -EINVAL;
495
496         if (fmt == subs->cur_audiofmt)
497                 return 0;
498
499         /* close the old interface */
500         if (subs->interface >= 0 && subs->interface != fmt->iface) {
501                 err = usb_set_interface(subs->dev, subs->interface, 0);
502                 if (err < 0) {
503                         dev_err(&dev->dev,
504                                 "%d:%d: return to setting 0 failed (%d)\n",
505                                 fmt->iface, fmt->altsetting, err);
506                         return -EIO;
507                 }
508                 subs->interface = -1;
509                 subs->altset_idx = 0;
510         }
511
512         /* set interface */
513         if (subs->interface != fmt->iface ||
514             subs->altset_idx != fmt->altset_idx) {
515
516                 err = snd_usb_select_mode_quirk(subs, fmt);
517                 if (err < 0)
518                         return -EIO;
519
520                 err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
521                 if (err < 0) {
522                         dev_err(&dev->dev,
523                                 "%d:%d: usb_set_interface failed (%d)\n",
524                                 fmt->iface, fmt->altsetting, err);
525                         return -EIO;
526                 }
527                 dev_dbg(&dev->dev, "setting usb interface %d:%d\n",
528                         fmt->iface, fmt->altsetting);
529                 subs->interface = fmt->iface;
530                 subs->altset_idx = fmt->altset_idx;
531
532                 snd_usb_set_interface_quirk(dev);
533         }
534
535         subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
536                                                    alts, fmt->endpoint, subs->direction,
537                                                    SND_USB_ENDPOINT_TYPE_DATA);
538
539         if (!subs->data_endpoint)
540                 return -EINVAL;
541
542         err = set_sync_endpoint(subs, fmt, dev, alts, altsd);
543         if (err < 0)
544                 return err;
545
546         err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt);
547         if (err < 0)
548                 return err;
549
550         subs->cur_audiofmt = fmt;
551
552         snd_usb_set_format_quirk(subs, fmt);
553
554         return 0;
555 }
556
557 /*
558  * Return the score of matching two audioformats.
559  * Veto the audioformat if:
560  * - It has no channels for some reason.
561  * - Requested PCM format is not supported.
562  * - Requested sample rate is not supported.
563  */
564 static int match_endpoint_audioformats(struct snd_usb_substream *subs,
565                                        struct audioformat *fp,
566                                        struct audioformat *match, int rate,
567                                        snd_pcm_format_t pcm_format)
568 {
569         int i;
570         int score = 0;
571
572         if (fp->channels < 1) {
573                 dev_dbg(&subs->dev->dev,
574                         "%s: (fmt @%p) no channels\n", __func__, fp);
575                 return 0;
576         }
577
578         if (!(fp->formats & pcm_format_to_bits(pcm_format))) {
579                 dev_dbg(&subs->dev->dev,
580                         "%s: (fmt @%p) no match for format %d\n", __func__,
581                         fp, pcm_format);
582                 return 0;
583         }
584
585         for (i = 0; i < fp->nr_rates; i++) {
586                 if (fp->rate_table[i] == rate) {
587                         score++;
588                         break;
589                 }
590         }
591         if (!score) {
592                 dev_dbg(&subs->dev->dev,
593                         "%s: (fmt @%p) no match for rate %d\n", __func__,
594                         fp, rate);
595                 return 0;
596         }
597
598         if (fp->channels == match->channels)
599                 score++;
600
601         dev_dbg(&subs->dev->dev,
602                 "%s: (fmt @%p) score %d\n", __func__, fp, score);
603
604         return score;
605 }
606
607 /*
608  * Configure the sync ep using the rate and pcm format of the data ep.
609  */
610 static int configure_sync_endpoint(struct snd_usb_substream *subs)
611 {
612         int ret;
613         struct audioformat *fp;
614         struct audioformat *sync_fp = NULL;
615         int cur_score = 0;
616         int sync_period_bytes = subs->period_bytes;
617         struct snd_usb_substream *sync_subs =
618                 &subs->stream->substream[subs->direction ^ 1];
619
620         if (subs->sync_endpoint->type != SND_USB_ENDPOINT_TYPE_DATA ||
621             !subs->stream)
622                 return snd_usb_endpoint_set_params(subs->sync_endpoint,
623                                                    subs->pcm_format,
624                                                    subs->channels,
625                                                    subs->period_bytes,
626                                                    0, 0,
627                                                    subs->cur_rate,
628                                                    subs->cur_audiofmt,
629                                                    NULL);
630
631         /* Try to find the best matching audioformat. */
632         list_for_each_entry(fp, &sync_subs->fmt_list, list) {
633                 int score = match_endpoint_audioformats(subs,
634                                                         fp, subs->cur_audiofmt,
635                         subs->cur_rate, subs->pcm_format);
636
637                 if (score > cur_score) {
638                         sync_fp = fp;
639                         cur_score = score;
640                 }
641         }
642
643         if (unlikely(sync_fp == NULL)) {
644                 dev_err(&subs->dev->dev,
645                         "%s: no valid audioformat for sync ep %x found\n",
646                         __func__, sync_subs->ep_num);
647                 return -EINVAL;
648         }
649
650         /*
651          * Recalculate the period bytes if channel number differ between
652          * data and sync ep audioformat.
653          */
654         if (sync_fp->channels != subs->channels) {
655                 sync_period_bytes = (subs->period_bytes / subs->channels) *
656                         sync_fp->channels;
657                 dev_dbg(&subs->dev->dev,
658                         "%s: adjusted sync ep period bytes (%d -> %d)\n",
659                         __func__, subs->period_bytes, sync_period_bytes);
660         }
661
662         ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
663                                           subs->pcm_format,
664                                           sync_fp->channels,
665                                           sync_period_bytes,
666                                           0, 0,
667                                           subs->cur_rate,
668                                           sync_fp,
669                                           NULL);
670
671         return ret;
672 }
673
674 /*
675  * configure endpoint params
676  *
677  * called  during initial setup and upon resume
678  */
679 static int configure_endpoint(struct snd_usb_substream *subs)
680 {
681         int ret;
682
683         /* format changed */
684         stop_endpoints(subs, true);
685         ret = snd_usb_endpoint_set_params(subs->data_endpoint,
686                                           subs->pcm_format,
687                                           subs->channels,
688                                           subs->period_bytes,
689                                           subs->period_frames,
690                                           subs->buffer_periods,
691                                           subs->cur_rate,
692                                           subs->cur_audiofmt,
693                                           subs->sync_endpoint);
694         if (ret < 0)
695                 return ret;
696
697         if (subs->sync_endpoint)
698                 ret = configure_sync_endpoint(subs);
699
700         return ret;
701 }
702
703 /*
704  * hw_params callback
705  *
706  * allocate a buffer and set the given audio format.
707  *
708  * so far we use a physically linear buffer although packetize transfer
709  * doesn't need a continuous area.
710  * if sg buffer is supported on the later version of alsa, we'll follow
711  * that.
712  */
713 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
714                              struct snd_pcm_hw_params *hw_params)
715 {
716         struct snd_usb_substream *subs = substream->runtime->private_data;
717         struct audioformat *fmt;
718         int ret;
719
720         ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
721                                                params_buffer_bytes(hw_params));
722         if (ret < 0)
723                 return ret;
724
725         subs->pcm_format = params_format(hw_params);
726         subs->period_bytes = params_period_bytes(hw_params);
727         subs->period_frames = params_period_size(hw_params);
728         subs->buffer_periods = params_periods(hw_params);
729         subs->channels = params_channels(hw_params);
730         subs->cur_rate = params_rate(hw_params);
731
732         fmt = find_format(subs);
733         if (!fmt) {
734                 dev_dbg(&subs->dev->dev,
735                         "cannot set format: format = %#x, rate = %d, channels = %d\n",
736                            subs->pcm_format, subs->cur_rate, subs->channels);
737                 return -EINVAL;
738         }
739
740         ret = snd_usb_lock_shutdown(subs->stream->chip);
741         if (ret < 0)
742                 return ret;
743         ret = set_format(subs, fmt);
744         snd_usb_unlock_shutdown(subs->stream->chip);
745         if (ret < 0)
746                 return ret;
747
748         subs->interface = fmt->iface;
749         subs->altset_idx = fmt->altset_idx;
750         subs->need_setup_ep = true;
751
752         return 0;
753 }
754
755 /*
756  * hw_free callback
757  *
758  * reset the audio format and release the buffer
759  */
760 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
761 {
762         struct snd_usb_substream *subs = substream->runtime->private_data;
763
764         subs->cur_audiofmt = NULL;
765         subs->cur_rate = 0;
766         subs->period_bytes = 0;
767         if (!snd_usb_lock_shutdown(subs->stream->chip)) {
768                 stop_endpoints(subs, true);
769                 snd_usb_endpoint_deactivate(subs->sync_endpoint);
770                 snd_usb_endpoint_deactivate(subs->data_endpoint);
771                 snd_usb_unlock_shutdown(subs->stream->chip);
772         }
773         return snd_pcm_lib_free_vmalloc_buffer(substream);
774 }
775
776 /*
777  * prepare callback
778  *
779  * only a few subtle things...
780  */
781 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
782 {
783         struct snd_pcm_runtime *runtime = substream->runtime;
784         struct snd_usb_substream *subs = runtime->private_data;
785         struct usb_host_interface *alts;
786         struct usb_interface *iface;
787         int ret;
788
789         if (! subs->cur_audiofmt) {
790                 dev_err(&subs->dev->dev, "no format is specified!\n");
791                 return -ENXIO;
792         }
793
794         ret = snd_usb_lock_shutdown(subs->stream->chip);
795         if (ret < 0)
796                 return ret;
797         if (snd_BUG_ON(!subs->data_endpoint)) {
798                 ret = -EIO;
799                 goto unlock;
800         }
801
802         snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
803         snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
804
805         ret = set_format(subs, subs->cur_audiofmt);
806         if (ret < 0)
807                 goto unlock;
808
809         iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
810         alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
811         ret = snd_usb_init_sample_rate(subs->stream->chip,
812                                        subs->cur_audiofmt->iface,
813                                        alts,
814                                        subs->cur_audiofmt,
815                                        subs->cur_rate);
816         if (ret < 0)
817                 goto unlock;
818
819         if (subs->need_setup_ep) {
820                 ret = configure_endpoint(subs);
821                 if (ret < 0)
822                         goto unlock;
823                 subs->need_setup_ep = false;
824         }
825
826         /* some unit conversions in runtime */
827         subs->data_endpoint->maxframesize =
828                 bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
829         subs->data_endpoint->curframesize =
830                 bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
831
832         /* reset the pointer */
833         subs->hwptr_done = 0;
834         subs->transfer_done = 0;
835         subs->last_delay = 0;
836         subs->last_frame_number = 0;
837         runtime->delay = 0;
838
839         /* for playback, submit the URBs now; otherwise, the first hwptr_done
840          * updates for all URBs would happen at the same time when starting */
841         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
842                 ret = start_endpoints(subs);
843
844  unlock:
845         snd_usb_unlock_shutdown(subs->stream->chip);
846         return ret;
847 }
848
849 static struct snd_pcm_hardware snd_usb_hardware =
850 {
851         .info =                 SNDRV_PCM_INFO_MMAP |
852                                 SNDRV_PCM_INFO_MMAP_VALID |
853                                 SNDRV_PCM_INFO_BATCH |
854                                 SNDRV_PCM_INFO_INTERLEAVED |
855                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
856                                 SNDRV_PCM_INFO_PAUSE,
857         .buffer_bytes_max =     1024 * 1024,
858         .period_bytes_min =     64,
859         .period_bytes_max =     512 * 1024,
860         .periods_min =          2,
861         .periods_max =          1024,
862 };
863
864 static int hw_check_valid_format(struct snd_usb_substream *subs,
865                                  struct snd_pcm_hw_params *params,
866                                  struct audioformat *fp)
867 {
868         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
869         struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
870         struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
871         struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
872         struct snd_mask check_fmts;
873         unsigned int ptime;
874
875         /* check the format */
876         snd_mask_none(&check_fmts);
877         check_fmts.bits[0] = (u32)fp->formats;
878         check_fmts.bits[1] = (u32)(fp->formats >> 32);
879         snd_mask_intersect(&check_fmts, fmts);
880         if (snd_mask_empty(&check_fmts)) {
881                 hwc_debug("   > check: no supported format %d\n", fp->format);
882                 return 0;
883         }
884         /* check the channels */
885         if (fp->channels < ct->min || fp->channels > ct->max) {
886                 hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
887                 return 0;
888         }
889         /* check the rate is within the range */
890         if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
891                 hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
892                 return 0;
893         }
894         if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
895                 hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
896                 return 0;
897         }
898         /* check whether the period time is >= the data packet interval */
899         if (subs->speed != USB_SPEED_FULL) {
900                 ptime = 125 * (1 << fp->datainterval);
901                 if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
902                         hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
903                         return 0;
904                 }
905         }
906         return 1;
907 }
908
909 static int hw_rule_rate(struct snd_pcm_hw_params *params,
910                         struct snd_pcm_hw_rule *rule)
911 {
912         struct snd_usb_substream *subs = rule->private;
913         struct audioformat *fp;
914         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
915         unsigned int rmin, rmax;
916         int changed;
917
918         hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
919         changed = 0;
920         rmin = rmax = 0;
921         list_for_each_entry(fp, &subs->fmt_list, list) {
922                 if (!hw_check_valid_format(subs, params, fp))
923                         continue;
924                 if (changed++) {
925                         if (rmin > fp->rate_min)
926                                 rmin = fp->rate_min;
927                         if (rmax < fp->rate_max)
928                                 rmax = fp->rate_max;
929                 } else {
930                         rmin = fp->rate_min;
931                         rmax = fp->rate_max;
932                 }
933         }
934
935         if (!changed) {
936                 hwc_debug("  --> get empty\n");
937                 it->empty = 1;
938                 return -EINVAL;
939         }
940
941         changed = 0;
942         if (it->min < rmin) {
943                 it->min = rmin;
944                 it->openmin = 0;
945                 changed = 1;
946         }
947         if (it->max > rmax) {
948                 it->max = rmax;
949                 it->openmax = 0;
950                 changed = 1;
951         }
952         if (snd_interval_checkempty(it)) {
953                 it->empty = 1;
954                 return -EINVAL;
955         }
956         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
957         return changed;
958 }
959
960
961 static int hw_rule_channels(struct snd_pcm_hw_params *params,
962                             struct snd_pcm_hw_rule *rule)
963 {
964         struct snd_usb_substream *subs = rule->private;
965         struct audioformat *fp;
966         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
967         unsigned int rmin, rmax;
968         int changed;
969
970         hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
971         changed = 0;
972         rmin = rmax = 0;
973         list_for_each_entry(fp, &subs->fmt_list, list) {
974                 if (!hw_check_valid_format(subs, params, fp))
975                         continue;
976                 if (changed++) {
977                         if (rmin > fp->channels)
978                                 rmin = fp->channels;
979                         if (rmax < fp->channels)
980                                 rmax = fp->channels;
981                 } else {
982                         rmin = fp->channels;
983                         rmax = fp->channels;
984                 }
985         }
986
987         if (!changed) {
988                 hwc_debug("  --> get empty\n");
989                 it->empty = 1;
990                 return -EINVAL;
991         }
992
993         changed = 0;
994         if (it->min < rmin) {
995                 it->min = rmin;
996                 it->openmin = 0;
997                 changed = 1;
998         }
999         if (it->max > rmax) {
1000                 it->max = rmax;
1001                 it->openmax = 0;
1002                 changed = 1;
1003         }
1004         if (snd_interval_checkempty(it)) {
1005                 it->empty = 1;
1006                 return -EINVAL;
1007         }
1008         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1009         return changed;
1010 }
1011
1012 static int hw_rule_format(struct snd_pcm_hw_params *params,
1013                           struct snd_pcm_hw_rule *rule)
1014 {
1015         struct snd_usb_substream *subs = rule->private;
1016         struct audioformat *fp;
1017         struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
1018         u64 fbits;
1019         u32 oldbits[2];
1020         int changed;
1021
1022         hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
1023         fbits = 0;
1024         list_for_each_entry(fp, &subs->fmt_list, list) {
1025                 if (!hw_check_valid_format(subs, params, fp))
1026                         continue;
1027                 fbits |= fp->formats;
1028         }
1029
1030         oldbits[0] = fmt->bits[0];
1031         oldbits[1] = fmt->bits[1];
1032         fmt->bits[0] &= (u32)fbits;
1033         fmt->bits[1] &= (u32)(fbits >> 32);
1034         if (!fmt->bits[0] && !fmt->bits[1]) {
1035                 hwc_debug("  --> get empty\n");
1036                 return -EINVAL;
1037         }
1038         changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
1039         hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
1040         return changed;
1041 }
1042
1043 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
1044                                struct snd_pcm_hw_rule *rule)
1045 {
1046         struct snd_usb_substream *subs = rule->private;
1047         struct audioformat *fp;
1048         struct snd_interval *it;
1049         unsigned char min_datainterval;
1050         unsigned int pmin;
1051         int changed;
1052
1053         it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
1054         hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
1055         min_datainterval = 0xff;
1056         list_for_each_entry(fp, &subs->fmt_list, list) {
1057                 if (!hw_check_valid_format(subs, params, fp))
1058                         continue;
1059                 min_datainterval = min(min_datainterval, fp->datainterval);
1060         }
1061         if (min_datainterval == 0xff) {
1062                 hwc_debug("  --> get empty\n");
1063                 it->empty = 1;
1064                 return -EINVAL;
1065         }
1066         pmin = 125 * (1 << min_datainterval);
1067         changed = 0;
1068         if (it->min < pmin) {
1069                 it->min = pmin;
1070                 it->openmin = 0;
1071                 changed = 1;
1072         }
1073         if (snd_interval_checkempty(it)) {
1074                 it->empty = 1;
1075                 return -EINVAL;
1076         }
1077         hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
1078         return changed;
1079 }
1080
1081 /*
1082  *  If the device supports unusual bit rates, does the request meet these?
1083  */
1084 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
1085                                   struct snd_usb_substream *subs)
1086 {
1087         struct audioformat *fp;
1088         int *rate_list;
1089         int count = 0, needs_knot = 0;
1090         int err;
1091
1092         kfree(subs->rate_list.list);
1093         subs->rate_list.list = NULL;
1094
1095         list_for_each_entry(fp, &subs->fmt_list, list) {
1096                 if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
1097                         return 0;
1098                 count += fp->nr_rates;
1099                 if (fp->rates & SNDRV_PCM_RATE_KNOT)
1100                         needs_knot = 1;
1101         }
1102         if (!needs_knot)
1103                 return 0;
1104
1105         subs->rate_list.list = rate_list =
1106                 kmalloc(sizeof(int) * count, GFP_KERNEL);
1107         if (!subs->rate_list.list)
1108                 return -ENOMEM;
1109         subs->rate_list.count = count;
1110         subs->rate_list.mask = 0;
1111         count = 0;
1112         list_for_each_entry(fp, &subs->fmt_list, list) {
1113                 int i;
1114                 for (i = 0; i < fp->nr_rates; i++)
1115                         rate_list[count++] = fp->rate_table[i];
1116         }
1117         err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1118                                          &subs->rate_list);
1119         if (err < 0)
1120                 return err;
1121
1122         return 0;
1123 }
1124
1125
1126 /*
1127  * set up the runtime hardware information.
1128  */
1129
1130 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1131 {
1132         struct audioformat *fp;
1133         unsigned int pt, ptmin;
1134         int param_period_time_if_needed;
1135         int err;
1136
1137         runtime->hw.formats = subs->formats;
1138
1139         runtime->hw.rate_min = 0x7fffffff;
1140         runtime->hw.rate_max = 0;
1141         runtime->hw.channels_min = 256;
1142         runtime->hw.channels_max = 0;
1143         runtime->hw.rates = 0;
1144         ptmin = UINT_MAX;
1145         /* check min/max rates and channels */
1146         list_for_each_entry(fp, &subs->fmt_list, list) {
1147                 runtime->hw.rates |= fp->rates;
1148                 if (runtime->hw.rate_min > fp->rate_min)
1149                         runtime->hw.rate_min = fp->rate_min;
1150                 if (runtime->hw.rate_max < fp->rate_max)
1151                         runtime->hw.rate_max = fp->rate_max;
1152                 if (runtime->hw.channels_min > fp->channels)
1153                         runtime->hw.channels_min = fp->channels;
1154                 if (runtime->hw.channels_max < fp->channels)
1155                         runtime->hw.channels_max = fp->channels;
1156                 if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1157                         /* FIXME: there might be more than one audio formats... */
1158                         runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1159                                 fp->frame_size;
1160                 }
1161                 pt = 125 * (1 << fp->datainterval);
1162                 ptmin = min(ptmin, pt);
1163         }
1164         err = snd_usb_autoresume(subs->stream->chip);
1165         if (err < 0)
1166                 return err;
1167
1168         param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1169         if (subs->speed == USB_SPEED_FULL)
1170                 /* full speed devices have fixed data packet interval */
1171                 ptmin = 1000;
1172         if (ptmin == 1000)
1173                 /* if period time doesn't go below 1 ms, no rules needed */
1174                 param_period_time_if_needed = -1;
1175         snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1176                                      ptmin, UINT_MAX);
1177
1178         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1179                                        hw_rule_rate, subs,
1180                                        SNDRV_PCM_HW_PARAM_FORMAT,
1181                                        SNDRV_PCM_HW_PARAM_CHANNELS,
1182                                        param_period_time_if_needed,
1183                                        -1)) < 0)
1184                 goto rep_err;
1185         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1186                                        hw_rule_channels, subs,
1187                                        SNDRV_PCM_HW_PARAM_FORMAT,
1188                                        SNDRV_PCM_HW_PARAM_RATE,
1189                                        param_period_time_if_needed,
1190                                        -1)) < 0)
1191                 goto rep_err;
1192         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1193                                        hw_rule_format, subs,
1194                                        SNDRV_PCM_HW_PARAM_RATE,
1195                                        SNDRV_PCM_HW_PARAM_CHANNELS,
1196                                        param_period_time_if_needed,
1197                                        -1)) < 0)
1198                 goto rep_err;
1199         if (param_period_time_if_needed >= 0) {
1200                 err = snd_pcm_hw_rule_add(runtime, 0,
1201                                           SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1202                                           hw_rule_period_time, subs,
1203                                           SNDRV_PCM_HW_PARAM_FORMAT,
1204                                           SNDRV_PCM_HW_PARAM_CHANNELS,
1205                                           SNDRV_PCM_HW_PARAM_RATE,
1206                                           -1);
1207                 if (err < 0)
1208                         goto rep_err;
1209         }
1210         if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
1211                 goto rep_err;
1212         return 0;
1213
1214 rep_err:
1215         snd_usb_autosuspend(subs->stream->chip);
1216         return err;
1217 }
1218
1219 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
1220 {
1221         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1222         struct snd_pcm_runtime *runtime = substream->runtime;
1223         struct snd_usb_substream *subs = &as->substream[direction];
1224
1225         subs->interface = -1;
1226         subs->altset_idx = 0;
1227         runtime->hw = snd_usb_hardware;
1228         runtime->private_data = subs;
1229         subs->pcm_substream = substream;
1230         /* runtime PM is also done there */
1231
1232         /* initialize DSD/DOP context */
1233         subs->dsd_dop.byte_idx = 0;
1234         subs->dsd_dop.channel = 0;
1235         subs->dsd_dop.marker = 1;
1236
1237         return setup_hw_info(runtime, subs);
1238 }
1239
1240 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
1241 {
1242         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1243         struct snd_usb_substream *subs = &as->substream[direction];
1244
1245         stop_endpoints(subs, true);
1246
1247         if (subs->interface >= 0 &&
1248             !snd_usb_lock_shutdown(subs->stream->chip)) {
1249                 usb_set_interface(subs->dev, subs->interface, 0);
1250                 subs->interface = -1;
1251                 snd_usb_unlock_shutdown(subs->stream->chip);
1252         }
1253
1254         subs->pcm_substream = NULL;
1255         snd_usb_autosuspend(subs->stream->chip);
1256
1257         return 0;
1258 }
1259
1260 /* Since a URB can handle only a single linear buffer, we must use double
1261  * buffering when the data to be transferred overflows the buffer boundary.
1262  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1263  * for all URBs.
1264  */
1265 static void retire_capture_urb(struct snd_usb_substream *subs,
1266                                struct urb *urb)
1267 {
1268         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1269         unsigned int stride, frames, bytes, oldptr;
1270         int i, period_elapsed = 0;
1271         unsigned long flags;
1272         unsigned char *cp;
1273         int current_frame_number;
1274
1275         /* read frame number here, update pointer in critical section */
1276         current_frame_number = usb_get_current_frame_number(subs->dev);
1277
1278         stride = runtime->frame_bits >> 3;
1279
1280         for (i = 0; i < urb->number_of_packets; i++) {
1281                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1282                 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1283                         dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1284                                 i, urb->iso_frame_desc[i].status);
1285                         // continue;
1286                 }
1287                 bytes = urb->iso_frame_desc[i].actual_length;
1288                 frames = bytes / stride;
1289                 if (!subs->txfr_quirk)
1290                         bytes = frames * stride;
1291                 if (bytes % (runtime->sample_bits >> 3) != 0) {
1292                         int oldbytes = bytes;
1293                         bytes = frames * stride;
1294                         dev_warn(&subs->dev->dev,
1295                                  "Corrected urb data len. %d->%d\n",
1296                                                         oldbytes, bytes);
1297                 }
1298                 /* update the current pointer */
1299                 spin_lock_irqsave(&subs->lock, flags);
1300                 oldptr = subs->hwptr_done;
1301                 subs->hwptr_done += bytes;
1302                 if (subs->hwptr_done >= runtime->buffer_size * stride)
1303                         subs->hwptr_done -= runtime->buffer_size * stride;
1304                 frames = (bytes + (oldptr % stride)) / stride;
1305                 subs->transfer_done += frames;
1306                 if (subs->transfer_done >= runtime->period_size) {
1307                         subs->transfer_done -= runtime->period_size;
1308                         period_elapsed = 1;
1309                 }
1310                 /* capture delay is by construction limited to one URB,
1311                  * reset delays here
1312                  */
1313                 runtime->delay = subs->last_delay = 0;
1314
1315                 /* realign last_frame_number */
1316                 subs->last_frame_number = current_frame_number;
1317                 subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1318
1319                 spin_unlock_irqrestore(&subs->lock, flags);
1320                 /* copy a data chunk */
1321                 if (oldptr + bytes > runtime->buffer_size * stride) {
1322                         unsigned int bytes1 =
1323                                         runtime->buffer_size * stride - oldptr;
1324                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
1325                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1326                 } else {
1327                         memcpy(runtime->dma_area + oldptr, cp, bytes);
1328                 }
1329         }
1330
1331         if (period_elapsed)
1332                 snd_pcm_period_elapsed(subs->pcm_substream);
1333 }
1334
1335 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1336                                              struct urb *urb, unsigned int bytes)
1337 {
1338         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1339         unsigned int stride = runtime->frame_bits >> 3;
1340         unsigned int dst_idx = 0;
1341         unsigned int src_idx = subs->hwptr_done;
1342         unsigned int wrap = runtime->buffer_size * stride;
1343         u8 *dst = urb->transfer_buffer;
1344         u8 *src = runtime->dma_area;
1345         u8 marker[] = { 0x05, 0xfa };
1346
1347         /*
1348          * The DSP DOP format defines a way to transport DSD samples over
1349          * normal PCM data endpoints. It requires stuffing of marker bytes
1350          * (0x05 and 0xfa, alternating per sample frame), and then expects
1351          * 2 additional bytes of actual payload. The whole frame is stored
1352          * LSB.
1353          *
1354          * Hence, for a stereo transport, the buffer layout looks like this,
1355          * where L refers to left channel samples and R to right.
1356          *
1357          *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1358          *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1359          *   .....
1360          *
1361          */
1362
1363         while (bytes--) {
1364                 if (++subs->dsd_dop.byte_idx == 3) {
1365                         /* frame boundary? */
1366                         dst[dst_idx++] = marker[subs->dsd_dop.marker];
1367                         src_idx += 2;
1368                         subs->dsd_dop.byte_idx = 0;
1369
1370                         if (++subs->dsd_dop.channel % runtime->channels == 0) {
1371                                 /* alternate the marker */
1372                                 subs->dsd_dop.marker++;
1373                                 subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1374                                 subs->dsd_dop.channel = 0;
1375                         }
1376                 } else {
1377                         /* stuff the DSD payload */
1378                         int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1379
1380                         if (subs->cur_audiofmt->dsd_bitrev)
1381                                 dst[dst_idx++] = bitrev8(src[idx]);
1382                         else
1383                                 dst[dst_idx++] = src[idx];
1384
1385                         subs->hwptr_done++;
1386                 }
1387         }
1388         if (subs->hwptr_done >= runtime->buffer_size * stride)
1389                 subs->hwptr_done -= runtime->buffer_size * stride;
1390 }
1391
1392 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1393                         int offset, int stride, unsigned int bytes)
1394 {
1395         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1396
1397         if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1398                 /* err, the transferred area goes over buffer boundary. */
1399                 unsigned int bytes1 =
1400                         runtime->buffer_size * stride - subs->hwptr_done;
1401                 memcpy(urb->transfer_buffer + offset,
1402                        runtime->dma_area + subs->hwptr_done, bytes1);
1403                 memcpy(urb->transfer_buffer + offset + bytes1,
1404                        runtime->dma_area, bytes - bytes1);
1405         } else {
1406                 memcpy(urb->transfer_buffer + offset,
1407                        runtime->dma_area + subs->hwptr_done, bytes);
1408         }
1409         subs->hwptr_done += bytes;
1410         if (subs->hwptr_done >= runtime->buffer_size * stride)
1411                 subs->hwptr_done -= runtime->buffer_size * stride;
1412 }
1413
1414 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1415                                       struct urb *urb, int stride,
1416                                       unsigned int bytes)
1417 {
1418         __le32 packet_length;
1419         int i;
1420
1421         /* Put __le32 length descriptor at start of each packet. */
1422         for (i = 0; i < urb->number_of_packets; i++) {
1423                 unsigned int length = urb->iso_frame_desc[i].length;
1424                 unsigned int offset = urb->iso_frame_desc[i].offset;
1425
1426                 packet_length = cpu_to_le32(length);
1427                 offset += i * sizeof(packet_length);
1428                 urb->iso_frame_desc[i].offset = offset;
1429                 urb->iso_frame_desc[i].length += sizeof(packet_length);
1430                 memcpy(urb->transfer_buffer + offset,
1431                        &packet_length, sizeof(packet_length));
1432                 copy_to_urb(subs, urb, offset + sizeof(packet_length),
1433                             stride, length);
1434         }
1435         /* Adjust transfer size accordingly. */
1436         bytes += urb->number_of_packets * sizeof(packet_length);
1437         return bytes;
1438 }
1439
1440 static void prepare_playback_urb(struct snd_usb_substream *subs,
1441                                  struct urb *urb)
1442 {
1443         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1444         struct snd_usb_endpoint *ep = subs->data_endpoint;
1445         struct snd_urb_ctx *ctx = urb->context;
1446         unsigned int counts, frames, bytes;
1447         int i, stride, period_elapsed = 0;
1448         unsigned long flags;
1449
1450         stride = runtime->frame_bits >> 3;
1451
1452         frames = 0;
1453         urb->number_of_packets = 0;
1454         spin_lock_irqsave(&subs->lock, flags);
1455         subs->frame_limit += ep->max_urb_frames;
1456         for (i = 0; i < ctx->packets; i++) {
1457                 if (ctx->packet_size[i])
1458                         counts = ctx->packet_size[i];
1459                 else
1460                         counts = snd_usb_endpoint_next_packet_size(ep);
1461
1462                 /* set up descriptor */
1463                 urb->iso_frame_desc[i].offset = frames * ep->stride;
1464                 urb->iso_frame_desc[i].length = counts * ep->stride;
1465                 frames += counts;
1466                 urb->number_of_packets++;
1467                 subs->transfer_done += counts;
1468                 if (subs->transfer_done >= runtime->period_size) {
1469                         subs->transfer_done -= runtime->period_size;
1470                         subs->frame_limit = 0;
1471                         period_elapsed = 1;
1472                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1473                                 if (subs->transfer_done > 0) {
1474                                         /* FIXME: fill-max mode is not
1475                                          * supported yet */
1476                                         frames -= subs->transfer_done;
1477                                         counts -= subs->transfer_done;
1478                                         urb->iso_frame_desc[i].length =
1479                                                 counts * ep->stride;
1480                                         subs->transfer_done = 0;
1481                                 }
1482                                 i++;
1483                                 if (i < ctx->packets) {
1484                                         /* add a transfer delimiter */
1485                                         urb->iso_frame_desc[i].offset =
1486                                                 frames * ep->stride;
1487                                         urb->iso_frame_desc[i].length = 0;
1488                                         urb->number_of_packets++;
1489                                 }
1490                                 break;
1491                         }
1492                 }
1493                 /* finish at the period boundary or after enough frames */
1494                 if ((period_elapsed ||
1495                                 subs->transfer_done >= subs->frame_limit) &&
1496                     !snd_usb_endpoint_implicit_feedback_sink(ep))
1497                         break;
1498         }
1499         bytes = frames * ep->stride;
1500
1501         if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1502                      subs->cur_audiofmt->dsd_dop)) {
1503                 fill_playback_urb_dsd_dop(subs, urb, bytes);
1504         } else if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1505                            subs->cur_audiofmt->dsd_bitrev)) {
1506                 /* bit-reverse the bytes */
1507                 u8 *buf = urb->transfer_buffer;
1508                 for (i = 0; i < bytes; i++) {
1509                         int idx = (subs->hwptr_done + i)
1510                                 % (runtime->buffer_size * stride);
1511                         buf[i] = bitrev8(runtime->dma_area[idx]);
1512                 }
1513
1514                 subs->hwptr_done += bytes;
1515                 if (subs->hwptr_done >= runtime->buffer_size * stride)
1516                         subs->hwptr_done -= runtime->buffer_size * stride;
1517         } else {
1518                 /* usual PCM */
1519                 if (!subs->tx_length_quirk)
1520                         copy_to_urb(subs, urb, 0, stride, bytes);
1521                 else
1522                         bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1523                         /* bytes is now amount of outgoing data */
1524         }
1525
1526         /* update delay with exact number of samples queued */
1527         runtime->delay = subs->last_delay;
1528         runtime->delay += frames;
1529         subs->last_delay = runtime->delay;
1530
1531         /* realign last_frame_number */
1532         subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1533         subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1534
1535         if (subs->trigger_tstamp_pending_update) {
1536                 /* this is the first actual URB submitted,
1537                  * update trigger timestamp to reflect actual start time
1538                  */
1539                 snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1540                 subs->trigger_tstamp_pending_update = false;
1541         }
1542
1543         spin_unlock_irqrestore(&subs->lock, flags);
1544         urb->transfer_buffer_length = bytes;
1545         if (period_elapsed)
1546                 snd_pcm_period_elapsed(subs->pcm_substream);
1547 }
1548
1549 /*
1550  * process after playback data complete
1551  * - decrease the delay count again
1552  */
1553 static void retire_playback_urb(struct snd_usb_substream *subs,
1554                                struct urb *urb)
1555 {
1556         unsigned long flags;
1557         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1558         struct snd_usb_endpoint *ep = subs->data_endpoint;
1559         int processed = urb->transfer_buffer_length / ep->stride;
1560         int est_delay;
1561
1562         /* ignore the delay accounting when procssed=0 is given, i.e.
1563          * silent payloads are procssed before handling the actual data
1564          */
1565         if (!processed)
1566                 return;
1567
1568         spin_lock_irqsave(&subs->lock, flags);
1569         if (!subs->last_delay)
1570                 goto out; /* short path */
1571
1572         est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1573         /* update delay with exact number of samples played */
1574         if (processed > subs->last_delay)
1575                 subs->last_delay = 0;
1576         else
1577                 subs->last_delay -= processed;
1578         runtime->delay = subs->last_delay;
1579
1580         /*
1581          * Report when delay estimate is off by more than 2ms.
1582          * The error should be lower than 2ms since the estimate relies
1583          * on two reads of a counter updated every ms.
1584          */
1585         if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1586                 dev_dbg_ratelimited(&subs->dev->dev,
1587                         "delay: estimated %d, actual %d\n",
1588                         est_delay, subs->last_delay);
1589
1590         if (!subs->running) {
1591                 /* update last_frame_number for delay counting here since
1592                  * prepare_playback_urb won't be called during pause
1593                  */
1594                 subs->last_frame_number =
1595                         usb_get_current_frame_number(subs->dev) & 0xff;
1596         }
1597
1598  out:
1599         spin_unlock_irqrestore(&subs->lock, flags);
1600 }
1601
1602 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1603 {
1604         return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1605 }
1606
1607 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1608 {
1609         return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1610 }
1611
1612 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1613 {
1614         return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1615 }
1616
1617 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1618 {
1619         return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1620 }
1621
1622 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1623                                               int cmd)
1624 {
1625         struct snd_usb_substream *subs = substream->runtime->private_data;
1626
1627         switch (cmd) {
1628         case SNDRV_PCM_TRIGGER_START:
1629                 subs->trigger_tstamp_pending_update = true;
1630         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1631                 subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1632                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1633                 subs->running = 1;
1634                 return 0;
1635         case SNDRV_PCM_TRIGGER_STOP:
1636                 stop_endpoints(subs, false);
1637                 subs->running = 0;
1638                 return 0;
1639         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1640                 subs->data_endpoint->prepare_data_urb = NULL;
1641                 /* keep retire_data_urb for delay calculation */
1642                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1643                 subs->running = 0;
1644                 return 0;
1645         }
1646
1647         return -EINVAL;
1648 }
1649
1650 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1651                                              int cmd)
1652 {
1653         int err;
1654         struct snd_usb_substream *subs = substream->runtime->private_data;
1655
1656         switch (cmd) {
1657         case SNDRV_PCM_TRIGGER_START:
1658                 err = start_endpoints(subs);
1659                 if (err < 0)
1660                         return err;
1661
1662                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1663                 subs->running = 1;
1664                 return 0;
1665         case SNDRV_PCM_TRIGGER_STOP:
1666                 stop_endpoints(subs, false);
1667                 subs->running = 0;
1668                 return 0;
1669         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1670                 subs->data_endpoint->retire_data_urb = NULL;
1671                 subs->running = 0;
1672                 return 0;
1673         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1674                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1675                 subs->running = 1;
1676                 return 0;
1677         }
1678
1679         return -EINVAL;
1680 }
1681
1682 static struct snd_pcm_ops snd_usb_playback_ops = {
1683         .open =         snd_usb_playback_open,
1684         .close =        snd_usb_playback_close,
1685         .ioctl =        snd_pcm_lib_ioctl,
1686         .hw_params =    snd_usb_hw_params,
1687         .hw_free =      snd_usb_hw_free,
1688         .prepare =      snd_usb_pcm_prepare,
1689         .trigger =      snd_usb_substream_playback_trigger,
1690         .pointer =      snd_usb_pcm_pointer,
1691         .page =         snd_pcm_lib_get_vmalloc_page,
1692         .mmap =         snd_pcm_lib_mmap_vmalloc,
1693 };
1694
1695 static struct snd_pcm_ops snd_usb_capture_ops = {
1696         .open =         snd_usb_capture_open,
1697         .close =        snd_usb_capture_close,
1698         .ioctl =        snd_pcm_lib_ioctl,
1699         .hw_params =    snd_usb_hw_params,
1700         .hw_free =      snd_usb_hw_free,
1701         .prepare =      snd_usb_pcm_prepare,
1702         .trigger =      snd_usb_substream_capture_trigger,
1703         .pointer =      snd_usb_pcm_pointer,
1704         .page =         snd_pcm_lib_get_vmalloc_page,
1705         .mmap =         snd_pcm_lib_mmap_vmalloc,
1706 };
1707
1708 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1709 {
1710         snd_pcm_set_ops(pcm, stream,
1711                         stream == SNDRV_PCM_STREAM_PLAYBACK ?
1712                         &snd_usb_playback_ops : &snd_usb_capture_ops);
1713 }