Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[platform/adaptation/renesas_rcar/renesas_kernel.git] / sound / usb / 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 (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         ep = get_endpoint(alts, 0)->bEndpointAddress;
163
164         data[0] = 1;
165         if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
166                                    USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
167                                    UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
168                                    data, sizeof(data))) < 0) {
169                 snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH\n",
170                            dev->devnum, iface, ep);
171                 return err;
172         }
173
174         return 0;
175 }
176
177 static int init_pitch_v2(struct snd_usb_audio *chip, int iface,
178                          struct usb_host_interface *alts,
179                          struct audioformat *fmt)
180 {
181         struct usb_device *dev = chip->dev;
182         unsigned char data[1];
183         int err;
184
185         data[0] = 1;
186         if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
187                                    USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
188                                    UAC2_EP_CS_PITCH << 8, 0,
189                                    data, sizeof(data))) < 0) {
190                 snd_printk(KERN_ERR "%d:%d:%d: cannot set enable PITCH (v2)\n",
191                            dev->devnum, iface, fmt->altsetting);
192                 return err;
193         }
194
195         return 0;
196 }
197
198 /*
199  * initialize the pitch control and sample rate
200  */
201 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
202                        struct usb_host_interface *alts,
203                        struct audioformat *fmt)
204 {
205         struct usb_interface_descriptor *altsd = get_iface_desc(alts);
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 (altsd->bInterfaceProtocol) {
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, bool can_sleep)
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                 snd_printdd(KERN_DEBUG "Starting data EP @%p\n", ep);
232
233                 ep->data_subs = subs;
234                 err = snd_usb_endpoint_start(ep, can_sleep);
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->alt_idx != subs->sync_endpoint->alt_idx) {
247                         err = usb_set_interface(subs->dev,
248                                                 subs->sync_endpoint->iface,
249                                                 subs->sync_endpoint->alt_idx);
250                         if (err < 0) {
251                                 snd_printk(KERN_ERR
252                                            "%d:%d:%d: cannot set interface (%d)\n",
253                                            subs->dev->devnum,
254                                            subs->sync_endpoint->iface,
255                                            subs->sync_endpoint->alt_idx, err);
256                                 return -EIO;
257                         }
258                 }
259
260                 snd_printdd(KERN_DEBUG "Starting sync EP @%p\n", ep);
261
262                 ep->sync_slave = subs->data_endpoint;
263                 err = snd_usb_endpoint_start(ep, can_sleep);
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 deactivate_endpoints(struct snd_usb_substream *subs)
288 {
289         int reta, retb;
290
291         reta = snd_usb_endpoint_deactivate(subs->sync_endpoint);
292         retb = snd_usb_endpoint_deactivate(subs->data_endpoint);
293
294         if (reta < 0)
295                 return reta;
296
297         if (retb < 0)
298                 return retb;
299
300         return 0;
301 }
302
303 /*
304  * find a matching format and set up the interface
305  */
306 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
307 {
308         struct usb_device *dev = subs->dev;
309         struct usb_host_interface *alts;
310         struct usb_interface_descriptor *altsd;
311         struct usb_interface *iface;
312         unsigned int ep, attr;
313         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
314         int err, implicit_fb = 0;
315
316         iface = usb_ifnum_to_if(dev, fmt->iface);
317         if (WARN_ON(!iface))
318                 return -EINVAL;
319         alts = &iface->altsetting[fmt->altset_idx];
320         altsd = get_iface_desc(alts);
321         if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
322                 return -EINVAL;
323
324         if (fmt == subs->cur_audiofmt)
325                 return 0;
326
327         /* close the old interface */
328         if (subs->interface >= 0 && subs->interface != fmt->iface) {
329                 err = usb_set_interface(subs->dev, subs->interface, 0);
330                 if (err < 0) {
331                         snd_printk(KERN_ERR "%d:%d:%d: return to setting 0 failed (%d)\n",
332                                 dev->devnum, fmt->iface, fmt->altsetting, err);
333                         return -EIO;
334                 }
335                 subs->interface = -1;
336                 subs->altset_idx = 0;
337         }
338
339         /* set interface */
340         if (subs->interface != fmt->iface ||
341             subs->altset_idx != fmt->altset_idx) {
342                 err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
343                 if (err < 0) {
344                         snd_printk(KERN_ERR "%d:%d:%d: usb_set_interface failed (%d)\n",
345                                    dev->devnum, fmt->iface, fmt->altsetting, err);
346                         return -EIO;
347                 }
348                 snd_printdd(KERN_INFO "setting usb interface %d:%d\n",
349                                 fmt->iface, fmt->altsetting);
350                 subs->interface = fmt->iface;
351                 subs->altset_idx = fmt->altset_idx;
352
353                 snd_usb_set_interface_quirk(dev);
354         }
355
356         subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
357                                                    alts, fmt->endpoint, subs->direction,
358                                                    SND_USB_ENDPOINT_TYPE_DATA);
359         if (!subs->data_endpoint)
360                 return -EINVAL;
361
362         /* we need a sync pipe in async OUT or adaptive IN mode */
363         /* check the number of EP, since some devices have broken
364          * descriptors which fool us.  if it has only one EP,
365          * assume it as adaptive-out or sync-in.
366          */
367         attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
368
369         switch (subs->stream->chip->usb_id) {
370         case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
371         case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
372                 if (is_playback) {
373                         implicit_fb = 1;
374                         ep = 0x81;
375                         iface = usb_ifnum_to_if(dev, 3);
376
377                         if (!iface || iface->num_altsetting == 0)
378                                 return -EINVAL;
379
380                         alts = &iface->altsetting[1];
381                         goto add_sync_ep;
382                 }
383                 break;
384         case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
385         case USB_ID(0x0763, 0x2081):
386                 if (is_playback) {
387                         implicit_fb = 1;
388                         ep = 0x81;
389                         iface = usb_ifnum_to_if(dev, 2);
390
391                         if (!iface || iface->num_altsetting == 0)
392                                 return -EINVAL;
393
394                         alts = &iface->altsetting[1];
395                         goto add_sync_ep;
396                 }
397         }
398
399         if (((is_playback && attr == USB_ENDPOINT_SYNC_ASYNC) ||
400              (!is_playback && attr == USB_ENDPOINT_SYNC_ADAPTIVE)) &&
401             altsd->bNumEndpoints >= 2) {
402                 /* check sync-pipe endpoint */
403                 /* ... and check descriptor size before accessing bSynchAddress
404                    because there is a version of the SB Audigy 2 NX firmware lacking
405                    the audio fields in the endpoint descriptors */
406                 if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
407                     (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
408                      get_endpoint(alts, 1)->bSynchAddress != 0 &&
409                      !implicit_fb)) {
410                         snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
411                                    dev->devnum, fmt->iface, fmt->altsetting,
412                                    get_endpoint(alts, 1)->bmAttributes,
413                                    get_endpoint(alts, 1)->bLength,
414                                    get_endpoint(alts, 1)->bSynchAddress);
415                         return -EINVAL;
416                 }
417                 ep = get_endpoint(alts, 1)->bEndpointAddress;
418                 if (!implicit_fb &&
419                     get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
420                     (( is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
421                      (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
422                         snd_printk(KERN_ERR "%d:%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
423                                    dev->devnum, fmt->iface, fmt->altsetting,
424                                    is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
425                         return -EINVAL;
426                 }
427
428                 implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
429                                 == USB_ENDPOINT_USAGE_IMPLICIT_FB;
430
431 add_sync_ep:
432                 subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
433                                                            alts, ep, !subs->direction,
434                                                            implicit_fb ?
435                                                                 SND_USB_ENDPOINT_TYPE_DATA :
436                                                                 SND_USB_ENDPOINT_TYPE_SYNC);
437                 if (!subs->sync_endpoint)
438                         return -EINVAL;
439
440                 subs->data_endpoint->sync_master = subs->sync_endpoint;
441         }
442
443         if ((err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt)) < 0)
444                 return err;
445
446         subs->cur_audiofmt = fmt;
447
448         snd_usb_set_format_quirk(subs, fmt);
449
450 #if 0
451         printk(KERN_DEBUG
452                "setting done: format = %d, rate = %d..%d, channels = %d\n",
453                fmt->format, fmt->rate_min, fmt->rate_max, fmt->channels);
454         printk(KERN_DEBUG
455                "  datapipe = 0x%0x, syncpipe = 0x%0x\n",
456                subs->datapipe, subs->syncpipe);
457 #endif
458
459         return 0;
460 }
461
462 /*
463  * Return the score of matching two audioformats.
464  * Veto the audioformat if:
465  * - It has no channels for some reason.
466  * - Requested PCM format is not supported.
467  * - Requested sample rate is not supported.
468  */
469 static int match_endpoint_audioformats(struct audioformat *fp,
470         struct audioformat *match, int rate,
471         snd_pcm_format_t pcm_format)
472 {
473         int i;
474         int score = 0;
475
476         if (fp->channels < 1) {
477                 snd_printdd("%s: (fmt @%p) no channels\n", __func__, fp);
478                 return 0;
479         }
480
481         if (!(fp->formats & pcm_format_to_bits(pcm_format))) {
482                 snd_printdd("%s: (fmt @%p) no match for format %d\n", __func__,
483                         fp, pcm_format);
484                 return 0;
485         }
486
487         for (i = 0; i < fp->nr_rates; i++) {
488                 if (fp->rate_table[i] == rate) {
489                         score++;
490                         break;
491                 }
492         }
493         if (!score) {
494                 snd_printdd("%s: (fmt @%p) no match for rate %d\n", __func__,
495                         fp, rate);
496                 return 0;
497         }
498
499         if (fp->channels == match->channels)
500                 score++;
501
502         snd_printdd("%s: (fmt @%p) score %d\n", __func__, fp, score);
503
504         return score;
505 }
506
507 /*
508  * Configure the sync ep using the rate and pcm format of the data ep.
509  */
510 static int configure_sync_endpoint(struct snd_usb_substream *subs)
511 {
512         int ret;
513         struct audioformat *fp;
514         struct audioformat *sync_fp = NULL;
515         int cur_score = 0;
516         int sync_period_bytes = subs->period_bytes;
517         struct snd_usb_substream *sync_subs =
518                 &subs->stream->substream[subs->direction ^ 1];
519
520         if (subs->sync_endpoint->type != SND_USB_ENDPOINT_TYPE_DATA ||
521             !subs->stream)
522                 return snd_usb_endpoint_set_params(subs->sync_endpoint,
523                                                    subs->pcm_format,
524                                                    subs->channels,
525                                                    subs->period_bytes,
526                                                    subs->cur_rate,
527                                                    subs->cur_audiofmt,
528                                                    NULL);
529
530         /* Try to find the best matching audioformat. */
531         list_for_each_entry(fp, &sync_subs->fmt_list, list) {
532                 int score = match_endpoint_audioformats(fp, subs->cur_audiofmt,
533                         subs->cur_rate, subs->pcm_format);
534
535                 if (score > cur_score) {
536                         sync_fp = fp;
537                         cur_score = score;
538                 }
539         }
540
541         if (unlikely(sync_fp == NULL)) {
542                 snd_printk(KERN_ERR "%s: no valid audioformat for sync ep %x found\n",
543                         __func__, sync_subs->ep_num);
544                 return -EINVAL;
545         }
546
547         /*
548          * Recalculate the period bytes if channel number differ between
549          * data and sync ep audioformat.
550          */
551         if (sync_fp->channels != subs->channels) {
552                 sync_period_bytes = (subs->period_bytes / subs->channels) *
553                         sync_fp->channels;
554                 snd_printdd("%s: adjusted sync ep period bytes (%d -> %d)\n",
555                         __func__, subs->period_bytes, sync_period_bytes);
556         }
557
558         ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
559                                           subs->pcm_format,
560                                           sync_fp->channels,
561                                           sync_period_bytes,
562                                           subs->cur_rate,
563                                           sync_fp,
564                                           NULL);
565
566         return ret;
567 }
568
569 /*
570  * configure endpoint params
571  *
572  * called  during initial setup and upon resume
573  */
574 static int configure_endpoint(struct snd_usb_substream *subs)
575 {
576         int ret;
577
578         /* format changed */
579         stop_endpoints(subs, true);
580         ret = snd_usb_endpoint_set_params(subs->data_endpoint,
581                                           subs->pcm_format,
582                                           subs->channels,
583                                           subs->period_bytes,
584                                           subs->cur_rate,
585                                           subs->cur_audiofmt,
586                                           subs->sync_endpoint);
587         if (ret < 0)
588                 return ret;
589
590         if (subs->sync_endpoint)
591                 ret = configure_sync_endpoint(subs);
592
593         return ret;
594 }
595
596 /*
597  * hw_params callback
598  *
599  * allocate a buffer and set the given audio format.
600  *
601  * so far we use a physically linear buffer although packetize transfer
602  * doesn't need a continuous area.
603  * if sg buffer is supported on the later version of alsa, we'll follow
604  * that.
605  */
606 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
607                              struct snd_pcm_hw_params *hw_params)
608 {
609         struct snd_usb_substream *subs = substream->runtime->private_data;
610         struct audioformat *fmt;
611         int ret;
612
613         ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
614                                                params_buffer_bytes(hw_params));
615         if (ret < 0)
616                 return ret;
617
618         subs->pcm_format = params_format(hw_params);
619         subs->period_bytes = params_period_bytes(hw_params);
620         subs->channels = params_channels(hw_params);
621         subs->cur_rate = params_rate(hw_params);
622
623         fmt = find_format(subs);
624         if (!fmt) {
625                 snd_printd(KERN_DEBUG "cannot set format: format = %#x, rate = %d, channels = %d\n",
626                            subs->pcm_format, subs->cur_rate, subs->channels);
627                 return -EINVAL;
628         }
629
630         down_read(&subs->stream->chip->shutdown_rwsem);
631         if (subs->stream->chip->shutdown)
632                 ret = -ENODEV;
633         else
634                 ret = set_format(subs, fmt);
635         up_read(&subs->stream->chip->shutdown_rwsem);
636         if (ret < 0)
637                 return ret;
638
639         subs->interface = fmt->iface;
640         subs->altset_idx = fmt->altset_idx;
641         subs->need_setup_ep = true;
642
643         return 0;
644 }
645
646 /*
647  * hw_free callback
648  *
649  * reset the audio format and release the buffer
650  */
651 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
652 {
653         struct snd_usb_substream *subs = substream->runtime->private_data;
654
655         subs->cur_audiofmt = NULL;
656         subs->cur_rate = 0;
657         subs->period_bytes = 0;
658         down_read(&subs->stream->chip->shutdown_rwsem);
659         if (!subs->stream->chip->shutdown) {
660                 stop_endpoints(subs, true);
661                 deactivate_endpoints(subs);
662         }
663         up_read(&subs->stream->chip->shutdown_rwsem);
664         return snd_pcm_lib_free_vmalloc_buffer(substream);
665 }
666
667 /*
668  * prepare callback
669  *
670  * only a few subtle things...
671  */
672 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
673 {
674         struct snd_pcm_runtime *runtime = substream->runtime;
675         struct snd_usb_substream *subs = runtime->private_data;
676         struct usb_host_interface *alts;
677         struct usb_interface *iface;
678         int ret;
679
680         if (! subs->cur_audiofmt) {
681                 snd_printk(KERN_ERR "usbaudio: no format is specified!\n");
682                 return -ENXIO;
683         }
684
685         down_read(&subs->stream->chip->shutdown_rwsem);
686         if (subs->stream->chip->shutdown) {
687                 ret = -ENODEV;
688                 goto unlock;
689         }
690         if (snd_BUG_ON(!subs->data_endpoint)) {
691                 ret = -EIO;
692                 goto unlock;
693         }
694
695         snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
696         snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
697
698         ret = set_format(subs, subs->cur_audiofmt);
699         if (ret < 0)
700                 goto unlock;
701
702         iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
703         alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
704         ret = snd_usb_init_sample_rate(subs->stream->chip,
705                                        subs->cur_audiofmt->iface,
706                                        alts,
707                                        subs->cur_audiofmt,
708                                        subs->cur_rate);
709         if (ret < 0)
710                 goto unlock;
711
712         if (subs->need_setup_ep) {
713                 ret = configure_endpoint(subs);
714                 if (ret < 0)
715                         goto unlock;
716                 subs->need_setup_ep = false;
717         }
718
719         /* some unit conversions in runtime */
720         subs->data_endpoint->maxframesize =
721                 bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
722         subs->data_endpoint->curframesize =
723                 bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
724
725         /* reset the pointer */
726         subs->hwptr_done = 0;
727         subs->transfer_done = 0;
728         subs->last_delay = 0;
729         subs->last_frame_number = 0;
730         runtime->delay = 0;
731
732         /* for playback, submit the URBs now; otherwise, the first hwptr_done
733          * updates for all URBs would happen at the same time when starting */
734         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
735                 ret = start_endpoints(subs, true);
736
737  unlock:
738         up_read(&subs->stream->chip->shutdown_rwsem);
739         return ret;
740 }
741
742 static struct snd_pcm_hardware snd_usb_hardware =
743 {
744         .info =                 SNDRV_PCM_INFO_MMAP |
745                                 SNDRV_PCM_INFO_MMAP_VALID |
746                                 SNDRV_PCM_INFO_BATCH |
747                                 SNDRV_PCM_INFO_INTERLEAVED |
748                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
749                                 SNDRV_PCM_INFO_PAUSE,
750         .buffer_bytes_max =     1024 * 1024,
751         .period_bytes_min =     64,
752         .period_bytes_max =     512 * 1024,
753         .periods_min =          2,
754         .periods_max =          1024,
755 };
756
757 static int hw_check_valid_format(struct snd_usb_substream *subs,
758                                  struct snd_pcm_hw_params *params,
759                                  struct audioformat *fp)
760 {
761         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
762         struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
763         struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
764         struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
765         struct snd_mask check_fmts;
766         unsigned int ptime;
767
768         /* check the format */
769         snd_mask_none(&check_fmts);
770         check_fmts.bits[0] = (u32)fp->formats;
771         check_fmts.bits[1] = (u32)(fp->formats >> 32);
772         snd_mask_intersect(&check_fmts, fmts);
773         if (snd_mask_empty(&check_fmts)) {
774                 hwc_debug("   > check: no supported format %d\n", fp->format);
775                 return 0;
776         }
777         /* check the channels */
778         if (fp->channels < ct->min || fp->channels > ct->max) {
779                 hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
780                 return 0;
781         }
782         /* check the rate is within the range */
783         if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
784                 hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
785                 return 0;
786         }
787         if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
788                 hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
789                 return 0;
790         }
791         /* check whether the period time is >= the data packet interval */
792         if (subs->speed != USB_SPEED_FULL) {
793                 ptime = 125 * (1 << fp->datainterval);
794                 if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
795                         hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
796                         return 0;
797                 }
798         }
799         return 1;
800 }
801
802 static int hw_rule_rate(struct snd_pcm_hw_params *params,
803                         struct snd_pcm_hw_rule *rule)
804 {
805         struct snd_usb_substream *subs = rule->private;
806         struct audioformat *fp;
807         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
808         unsigned int rmin, rmax;
809         int changed;
810
811         hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
812         changed = 0;
813         rmin = rmax = 0;
814         list_for_each_entry(fp, &subs->fmt_list, list) {
815                 if (!hw_check_valid_format(subs, params, fp))
816                         continue;
817                 if (changed++) {
818                         if (rmin > fp->rate_min)
819                                 rmin = fp->rate_min;
820                         if (rmax < fp->rate_max)
821                                 rmax = fp->rate_max;
822                 } else {
823                         rmin = fp->rate_min;
824                         rmax = fp->rate_max;
825                 }
826         }
827
828         if (!changed) {
829                 hwc_debug("  --> get empty\n");
830                 it->empty = 1;
831                 return -EINVAL;
832         }
833
834         changed = 0;
835         if (it->min < rmin) {
836                 it->min = rmin;
837                 it->openmin = 0;
838                 changed = 1;
839         }
840         if (it->max > rmax) {
841                 it->max = rmax;
842                 it->openmax = 0;
843                 changed = 1;
844         }
845         if (snd_interval_checkempty(it)) {
846                 it->empty = 1;
847                 return -EINVAL;
848         }
849         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
850         return changed;
851 }
852
853
854 static int hw_rule_channels(struct snd_pcm_hw_params *params,
855                             struct snd_pcm_hw_rule *rule)
856 {
857         struct snd_usb_substream *subs = rule->private;
858         struct audioformat *fp;
859         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
860         unsigned int rmin, rmax;
861         int changed;
862
863         hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
864         changed = 0;
865         rmin = rmax = 0;
866         list_for_each_entry(fp, &subs->fmt_list, list) {
867                 if (!hw_check_valid_format(subs, params, fp))
868                         continue;
869                 if (changed++) {
870                         if (rmin > fp->channels)
871                                 rmin = fp->channels;
872                         if (rmax < fp->channels)
873                                 rmax = fp->channels;
874                 } else {
875                         rmin = fp->channels;
876                         rmax = fp->channels;
877                 }
878         }
879
880         if (!changed) {
881                 hwc_debug("  --> get empty\n");
882                 it->empty = 1;
883                 return -EINVAL;
884         }
885
886         changed = 0;
887         if (it->min < rmin) {
888                 it->min = rmin;
889                 it->openmin = 0;
890                 changed = 1;
891         }
892         if (it->max > rmax) {
893                 it->max = rmax;
894                 it->openmax = 0;
895                 changed = 1;
896         }
897         if (snd_interval_checkempty(it)) {
898                 it->empty = 1;
899                 return -EINVAL;
900         }
901         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
902         return changed;
903 }
904
905 static int hw_rule_format(struct snd_pcm_hw_params *params,
906                           struct snd_pcm_hw_rule *rule)
907 {
908         struct snd_usb_substream *subs = rule->private;
909         struct audioformat *fp;
910         struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
911         u64 fbits;
912         u32 oldbits[2];
913         int changed;
914
915         hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
916         fbits = 0;
917         list_for_each_entry(fp, &subs->fmt_list, list) {
918                 if (!hw_check_valid_format(subs, params, fp))
919                         continue;
920                 fbits |= fp->formats;
921         }
922
923         oldbits[0] = fmt->bits[0];
924         oldbits[1] = fmt->bits[1];
925         fmt->bits[0] &= (u32)fbits;
926         fmt->bits[1] &= (u32)(fbits >> 32);
927         if (!fmt->bits[0] && !fmt->bits[1]) {
928                 hwc_debug("  --> get empty\n");
929                 return -EINVAL;
930         }
931         changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
932         hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
933         return changed;
934 }
935
936 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
937                                struct snd_pcm_hw_rule *rule)
938 {
939         struct snd_usb_substream *subs = rule->private;
940         struct audioformat *fp;
941         struct snd_interval *it;
942         unsigned char min_datainterval;
943         unsigned int pmin;
944         int changed;
945
946         it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
947         hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
948         min_datainterval = 0xff;
949         list_for_each_entry(fp, &subs->fmt_list, list) {
950                 if (!hw_check_valid_format(subs, params, fp))
951                         continue;
952                 min_datainterval = min(min_datainterval, fp->datainterval);
953         }
954         if (min_datainterval == 0xff) {
955                 hwc_debug("  --> get empty\n");
956                 it->empty = 1;
957                 return -EINVAL;
958         }
959         pmin = 125 * (1 << min_datainterval);
960         changed = 0;
961         if (it->min < pmin) {
962                 it->min = pmin;
963                 it->openmin = 0;
964                 changed = 1;
965         }
966         if (snd_interval_checkempty(it)) {
967                 it->empty = 1;
968                 return -EINVAL;
969         }
970         hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
971         return changed;
972 }
973
974 /*
975  *  If the device supports unusual bit rates, does the request meet these?
976  */
977 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
978                                   struct snd_usb_substream *subs)
979 {
980         struct audioformat *fp;
981         int *rate_list;
982         int count = 0, needs_knot = 0;
983         int err;
984
985         kfree(subs->rate_list.list);
986         subs->rate_list.list = NULL;
987
988         list_for_each_entry(fp, &subs->fmt_list, list) {
989                 if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
990                         return 0;
991                 count += fp->nr_rates;
992                 if (fp->rates & SNDRV_PCM_RATE_KNOT)
993                         needs_knot = 1;
994         }
995         if (!needs_knot)
996                 return 0;
997
998         subs->rate_list.list = rate_list =
999                 kmalloc(sizeof(int) * count, GFP_KERNEL);
1000         if (!subs->rate_list.list)
1001                 return -ENOMEM;
1002         subs->rate_list.count = count;
1003         subs->rate_list.mask = 0;
1004         count = 0;
1005         list_for_each_entry(fp, &subs->fmt_list, list) {
1006                 int i;
1007                 for (i = 0; i < fp->nr_rates; i++)
1008                         rate_list[count++] = fp->rate_table[i];
1009         }
1010         err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1011                                          &subs->rate_list);
1012         if (err < 0)
1013                 return err;
1014
1015         return 0;
1016 }
1017
1018
1019 /*
1020  * set up the runtime hardware information.
1021  */
1022
1023 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1024 {
1025         struct audioformat *fp;
1026         unsigned int pt, ptmin;
1027         int param_period_time_if_needed;
1028         int err;
1029
1030         runtime->hw.formats = subs->formats;
1031
1032         runtime->hw.rate_min = 0x7fffffff;
1033         runtime->hw.rate_max = 0;
1034         runtime->hw.channels_min = 256;
1035         runtime->hw.channels_max = 0;
1036         runtime->hw.rates = 0;
1037         ptmin = UINT_MAX;
1038         /* check min/max rates and channels */
1039         list_for_each_entry(fp, &subs->fmt_list, list) {
1040                 runtime->hw.rates |= fp->rates;
1041                 if (runtime->hw.rate_min > fp->rate_min)
1042                         runtime->hw.rate_min = fp->rate_min;
1043                 if (runtime->hw.rate_max < fp->rate_max)
1044                         runtime->hw.rate_max = fp->rate_max;
1045                 if (runtime->hw.channels_min > fp->channels)
1046                         runtime->hw.channels_min = fp->channels;
1047                 if (runtime->hw.channels_max < fp->channels)
1048                         runtime->hw.channels_max = fp->channels;
1049                 if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1050                         /* FIXME: there might be more than one audio formats... */
1051                         runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1052                                 fp->frame_size;
1053                 }
1054                 pt = 125 * (1 << fp->datainterval);
1055                 ptmin = min(ptmin, pt);
1056         }
1057         err = snd_usb_autoresume(subs->stream->chip);
1058         if (err < 0)
1059                 return err;
1060
1061         param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1062         if (subs->speed == USB_SPEED_FULL)
1063                 /* full speed devices have fixed data packet interval */
1064                 ptmin = 1000;
1065         if (ptmin == 1000)
1066                 /* if period time doesn't go below 1 ms, no rules needed */
1067                 param_period_time_if_needed = -1;
1068         snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1069                                      ptmin, UINT_MAX);
1070
1071         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1072                                        hw_rule_rate, subs,
1073                                        SNDRV_PCM_HW_PARAM_FORMAT,
1074                                        SNDRV_PCM_HW_PARAM_CHANNELS,
1075                                        param_period_time_if_needed,
1076                                        -1)) < 0)
1077                 goto rep_err;
1078         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1079                                        hw_rule_channels, subs,
1080                                        SNDRV_PCM_HW_PARAM_FORMAT,
1081                                        SNDRV_PCM_HW_PARAM_RATE,
1082                                        param_period_time_if_needed,
1083                                        -1)) < 0)
1084                 goto rep_err;
1085         if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1086                                        hw_rule_format, subs,
1087                                        SNDRV_PCM_HW_PARAM_RATE,
1088                                        SNDRV_PCM_HW_PARAM_CHANNELS,
1089                                        param_period_time_if_needed,
1090                                        -1)) < 0)
1091                 goto rep_err;
1092         if (param_period_time_if_needed >= 0) {
1093                 err = snd_pcm_hw_rule_add(runtime, 0,
1094                                           SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1095                                           hw_rule_period_time, subs,
1096                                           SNDRV_PCM_HW_PARAM_FORMAT,
1097                                           SNDRV_PCM_HW_PARAM_CHANNELS,
1098                                           SNDRV_PCM_HW_PARAM_RATE,
1099                                           -1);
1100                 if (err < 0)
1101                         goto rep_err;
1102         }
1103         if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
1104                 goto rep_err;
1105         return 0;
1106
1107 rep_err:
1108         snd_usb_autosuspend(subs->stream->chip);
1109         return err;
1110 }
1111
1112 static int snd_usb_pcm_open(struct snd_pcm_substream *substream, int direction)
1113 {
1114         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1115         struct snd_pcm_runtime *runtime = substream->runtime;
1116         struct snd_usb_substream *subs = &as->substream[direction];
1117
1118         subs->interface = -1;
1119         subs->altset_idx = 0;
1120         runtime->hw = snd_usb_hardware;
1121         runtime->private_data = subs;
1122         subs->pcm_substream = substream;
1123         /* runtime PM is also done there */
1124
1125         /* initialize DSD/DOP context */
1126         subs->dsd_dop.byte_idx = 0;
1127         subs->dsd_dop.channel = 0;
1128         subs->dsd_dop.marker = 1;
1129
1130         return setup_hw_info(runtime, subs);
1131 }
1132
1133 static int snd_usb_pcm_close(struct snd_pcm_substream *substream, int direction)
1134 {
1135         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1136         struct snd_usb_substream *subs = &as->substream[direction];
1137
1138         stop_endpoints(subs, true);
1139
1140         if (!as->chip->shutdown && subs->interface >= 0) {
1141                 usb_set_interface(subs->dev, subs->interface, 0);
1142                 subs->interface = -1;
1143         }
1144
1145         subs->pcm_substream = NULL;
1146         snd_usb_autosuspend(subs->stream->chip);
1147
1148         return 0;
1149 }
1150
1151 /* Since a URB can handle only a single linear buffer, we must use double
1152  * buffering when the data to be transferred overflows the buffer boundary.
1153  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1154  * for all URBs.
1155  */
1156 static void retire_capture_urb(struct snd_usb_substream *subs,
1157                                struct urb *urb)
1158 {
1159         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1160         unsigned int stride, frames, bytes, oldptr;
1161         int i, period_elapsed = 0;
1162         unsigned long flags;
1163         unsigned char *cp;
1164         int current_frame_number;
1165
1166         /* read frame number here, update pointer in critical section */
1167         current_frame_number = usb_get_current_frame_number(subs->dev);
1168
1169         stride = runtime->frame_bits >> 3;
1170
1171         for (i = 0; i < urb->number_of_packets; i++) {
1172                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1173                 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1174                         snd_printdd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
1175                         // continue;
1176                 }
1177                 bytes = urb->iso_frame_desc[i].actual_length;
1178                 frames = bytes / stride;
1179                 if (!subs->txfr_quirk)
1180                         bytes = frames * stride;
1181                 if (bytes % (runtime->sample_bits >> 3) != 0) {
1182                         int oldbytes = bytes;
1183                         bytes = frames * stride;
1184                         snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
1185                                                         oldbytes, bytes);
1186                 }
1187                 /* update the current pointer */
1188                 spin_lock_irqsave(&subs->lock, flags);
1189                 oldptr = subs->hwptr_done;
1190                 subs->hwptr_done += bytes;
1191                 if (subs->hwptr_done >= runtime->buffer_size * stride)
1192                         subs->hwptr_done -= runtime->buffer_size * stride;
1193                 frames = (bytes + (oldptr % stride)) / stride;
1194                 subs->transfer_done += frames;
1195                 if (subs->transfer_done >= runtime->period_size) {
1196                         subs->transfer_done -= runtime->period_size;
1197                         period_elapsed = 1;
1198                 }
1199                 /* capture delay is by construction limited to one URB,
1200                  * reset delays here
1201                  */
1202                 runtime->delay = subs->last_delay = 0;
1203
1204                 /* realign last_frame_number */
1205                 subs->last_frame_number = current_frame_number;
1206                 subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1207
1208                 spin_unlock_irqrestore(&subs->lock, flags);
1209                 /* copy a data chunk */
1210                 if (oldptr + bytes > runtime->buffer_size * stride) {
1211                         unsigned int bytes1 =
1212                                         runtime->buffer_size * stride - oldptr;
1213                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
1214                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1215                 } else {
1216                         memcpy(runtime->dma_area + oldptr, cp, bytes);
1217                 }
1218         }
1219
1220         if (period_elapsed)
1221                 snd_pcm_period_elapsed(subs->pcm_substream);
1222 }
1223
1224 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1225                                              struct urb *urb, unsigned int bytes)
1226 {
1227         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1228         unsigned int stride = runtime->frame_bits >> 3;
1229         unsigned int dst_idx = 0;
1230         unsigned int src_idx = subs->hwptr_done;
1231         unsigned int wrap = runtime->buffer_size * stride;
1232         u8 *dst = urb->transfer_buffer;
1233         u8 *src = runtime->dma_area;
1234         u8 marker[] = { 0x05, 0xfa };
1235
1236         /*
1237          * The DSP DOP format defines a way to transport DSD samples over
1238          * normal PCM data endpoints. It requires stuffing of marker bytes
1239          * (0x05 and 0xfa, alternating per sample frame), and then expects
1240          * 2 additional bytes of actual payload. The whole frame is stored
1241          * LSB.
1242          *
1243          * Hence, for a stereo transport, the buffer layout looks like this,
1244          * where L refers to left channel samples and R to right.
1245          *
1246          *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1247          *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1248          *   .....
1249          *
1250          */
1251
1252         while (bytes--) {
1253                 if (++subs->dsd_dop.byte_idx == 3) {
1254                         /* frame boundary? */
1255                         dst[dst_idx++] = marker[subs->dsd_dop.marker];
1256                         src_idx += 2;
1257                         subs->dsd_dop.byte_idx = 0;
1258
1259                         if (++subs->dsd_dop.channel % runtime->channels == 0) {
1260                                 /* alternate the marker */
1261                                 subs->dsd_dop.marker++;
1262                                 subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1263                                 subs->dsd_dop.channel = 0;
1264                         }
1265                 } else {
1266                         /* stuff the DSD payload */
1267                         int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1268
1269                         if (subs->cur_audiofmt->dsd_bitrev)
1270                                 dst[dst_idx++] = bitrev8(src[idx]);
1271                         else
1272                                 dst[dst_idx++] = src[idx];
1273
1274                         subs->hwptr_done++;
1275                 }
1276         }
1277 }
1278
1279 static void prepare_playback_urb(struct snd_usb_substream *subs,
1280                                  struct urb *urb)
1281 {
1282         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1283         struct snd_usb_endpoint *ep = subs->data_endpoint;
1284         struct snd_urb_ctx *ctx = urb->context;
1285         unsigned int counts, frames, bytes;
1286         int i, stride, period_elapsed = 0;
1287         unsigned long flags;
1288
1289         stride = runtime->frame_bits >> 3;
1290
1291         frames = 0;
1292         urb->number_of_packets = 0;
1293         spin_lock_irqsave(&subs->lock, flags);
1294         for (i = 0; i < ctx->packets; i++) {
1295                 if (ctx->packet_size[i])
1296                         counts = ctx->packet_size[i];
1297                 else
1298                         counts = snd_usb_endpoint_next_packet_size(ep);
1299
1300                 /* set up descriptor */
1301                 urb->iso_frame_desc[i].offset = frames * ep->stride;
1302                 urb->iso_frame_desc[i].length = counts * ep->stride;
1303                 frames += counts;
1304                 urb->number_of_packets++;
1305                 subs->transfer_done += counts;
1306                 if (subs->transfer_done >= runtime->period_size) {
1307                         subs->transfer_done -= runtime->period_size;
1308                         period_elapsed = 1;
1309                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1310                                 if (subs->transfer_done > 0) {
1311                                         /* FIXME: fill-max mode is not
1312                                          * supported yet */
1313                                         frames -= subs->transfer_done;
1314                                         counts -= subs->transfer_done;
1315                                         urb->iso_frame_desc[i].length =
1316                                                 counts * ep->stride;
1317                                         subs->transfer_done = 0;
1318                                 }
1319                                 i++;
1320                                 if (i < ctx->packets) {
1321                                         /* add a transfer delimiter */
1322                                         urb->iso_frame_desc[i].offset =
1323                                                 frames * ep->stride;
1324                                         urb->iso_frame_desc[i].length = 0;
1325                                         urb->number_of_packets++;
1326                                 }
1327                                 break;
1328                         }
1329                 }
1330                 if (period_elapsed &&
1331                     !snd_usb_endpoint_implicit_feedback_sink(subs->data_endpoint)) /* finish at the period boundary */
1332                         break;
1333         }
1334         bytes = frames * ep->stride;
1335
1336         if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1337                      subs->cur_audiofmt->dsd_dop)) {
1338                 fill_playback_urb_dsd_dop(subs, urb, bytes);
1339         } else if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1340                            subs->cur_audiofmt->dsd_bitrev)) {
1341                 /* bit-reverse the bytes */
1342                 u8 *buf = urb->transfer_buffer;
1343                 for (i = 0; i < bytes; i++) {
1344                         int idx = (subs->hwptr_done + i)
1345                                 % (runtime->buffer_size * stride);
1346                         buf[i] = bitrev8(runtime->dma_area[idx]);
1347                 }
1348
1349                 subs->hwptr_done += bytes;
1350         } else {
1351                 /* usual PCM */
1352                 if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1353                         /* err, the transferred area goes over buffer boundary. */
1354                         unsigned int bytes1 =
1355                                 runtime->buffer_size * stride - subs->hwptr_done;
1356                         memcpy(urb->transfer_buffer,
1357                                runtime->dma_area + subs->hwptr_done, bytes1);
1358                         memcpy(urb->transfer_buffer + bytes1,
1359                                runtime->dma_area, bytes - bytes1);
1360                 } else {
1361                         memcpy(urb->transfer_buffer,
1362                                runtime->dma_area + subs->hwptr_done, bytes);
1363                 }
1364
1365                 subs->hwptr_done += bytes;
1366         }
1367
1368         if (subs->hwptr_done >= runtime->buffer_size * stride)
1369                 subs->hwptr_done -= runtime->buffer_size * stride;
1370
1371         /* update delay with exact number of samples queued */
1372         runtime->delay = subs->last_delay;
1373         runtime->delay += frames;
1374         subs->last_delay = runtime->delay;
1375
1376         /* realign last_frame_number */
1377         subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1378         subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1379
1380         spin_unlock_irqrestore(&subs->lock, flags);
1381         urb->transfer_buffer_length = bytes;
1382         if (period_elapsed)
1383                 snd_pcm_period_elapsed(subs->pcm_substream);
1384 }
1385
1386 /*
1387  * process after playback data complete
1388  * - decrease the delay count again
1389  */
1390 static void retire_playback_urb(struct snd_usb_substream *subs,
1391                                struct urb *urb)
1392 {
1393         unsigned long flags;
1394         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1395         struct snd_usb_endpoint *ep = subs->data_endpoint;
1396         int processed = urb->transfer_buffer_length / ep->stride;
1397         int est_delay;
1398
1399         /* ignore the delay accounting when procssed=0 is given, i.e.
1400          * silent payloads are procssed before handling the actual data
1401          */
1402         if (!processed)
1403                 return;
1404
1405         spin_lock_irqsave(&subs->lock, flags);
1406         if (!subs->last_delay)
1407                 goto out; /* short path */
1408
1409         est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1410         /* update delay with exact number of samples played */
1411         if (processed > subs->last_delay)
1412                 subs->last_delay = 0;
1413         else
1414                 subs->last_delay -= processed;
1415         runtime->delay = subs->last_delay;
1416
1417         /*
1418          * Report when delay estimate is off by more than 2ms.
1419          * The error should be lower than 2ms since the estimate relies
1420          * on two reads of a counter updated every ms.
1421          */
1422         if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1423                 snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
1424                         est_delay, subs->last_delay);
1425
1426         if (!subs->running) {
1427                 /* update last_frame_number for delay counting here since
1428                  * prepare_playback_urb won't be called during pause
1429                  */
1430                 subs->last_frame_number =
1431                         usb_get_current_frame_number(subs->dev) & 0xff;
1432         }
1433
1434  out:
1435         spin_unlock_irqrestore(&subs->lock, flags);
1436 }
1437
1438 static int snd_usb_playback_open(struct snd_pcm_substream *substream)
1439 {
1440         return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_PLAYBACK);
1441 }
1442
1443 static int snd_usb_playback_close(struct snd_pcm_substream *substream)
1444 {
1445         return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_PLAYBACK);
1446 }
1447
1448 static int snd_usb_capture_open(struct snd_pcm_substream *substream)
1449 {
1450         return snd_usb_pcm_open(substream, SNDRV_PCM_STREAM_CAPTURE);
1451 }
1452
1453 static int snd_usb_capture_close(struct snd_pcm_substream *substream)
1454 {
1455         return snd_usb_pcm_close(substream, SNDRV_PCM_STREAM_CAPTURE);
1456 }
1457
1458 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1459                                               int cmd)
1460 {
1461         struct snd_usb_substream *subs = substream->runtime->private_data;
1462
1463         switch (cmd) {
1464         case SNDRV_PCM_TRIGGER_START:
1465         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1466                 subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1467                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1468                 subs->running = 1;
1469                 return 0;
1470         case SNDRV_PCM_TRIGGER_STOP:
1471                 stop_endpoints(subs, false);
1472                 subs->running = 0;
1473                 return 0;
1474         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1475                 subs->data_endpoint->prepare_data_urb = NULL;
1476                 /* keep retire_data_urb for delay calculation */
1477                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1478                 subs->running = 0;
1479                 return 0;
1480         }
1481
1482         return -EINVAL;
1483 }
1484
1485 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1486                                              int cmd)
1487 {
1488         int err;
1489         struct snd_usb_substream *subs = substream->runtime->private_data;
1490
1491         switch (cmd) {
1492         case SNDRV_PCM_TRIGGER_START:
1493                 err = start_endpoints(subs, false);
1494                 if (err < 0)
1495                         return err;
1496
1497                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1498                 subs->running = 1;
1499                 return 0;
1500         case SNDRV_PCM_TRIGGER_STOP:
1501                 stop_endpoints(subs, false);
1502                 subs->running = 0;
1503                 return 0;
1504         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1505                 subs->data_endpoint->retire_data_urb = NULL;
1506                 subs->running = 0;
1507                 return 0;
1508         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1509                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1510                 subs->running = 1;
1511                 return 0;
1512         }
1513
1514         return -EINVAL;
1515 }
1516
1517 static struct snd_pcm_ops snd_usb_playback_ops = {
1518         .open =         snd_usb_playback_open,
1519         .close =        snd_usb_playback_close,
1520         .ioctl =        snd_pcm_lib_ioctl,
1521         .hw_params =    snd_usb_hw_params,
1522         .hw_free =      snd_usb_hw_free,
1523         .prepare =      snd_usb_pcm_prepare,
1524         .trigger =      snd_usb_substream_playback_trigger,
1525         .pointer =      snd_usb_pcm_pointer,
1526         .page =         snd_pcm_lib_get_vmalloc_page,
1527         .mmap =         snd_pcm_lib_mmap_vmalloc,
1528 };
1529
1530 static struct snd_pcm_ops snd_usb_capture_ops = {
1531         .open =         snd_usb_capture_open,
1532         .close =        snd_usb_capture_close,
1533         .ioctl =        snd_pcm_lib_ioctl,
1534         .hw_params =    snd_usb_hw_params,
1535         .hw_free =      snd_usb_hw_free,
1536         .prepare =      snd_usb_pcm_prepare,
1537         .trigger =      snd_usb_substream_capture_trigger,
1538         .pointer =      snd_usb_pcm_pointer,
1539         .page =         snd_pcm_lib_get_vmalloc_page,
1540         .mmap =         snd_pcm_lib_mmap_vmalloc,
1541 };
1542
1543 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1544 {
1545         snd_pcm_set_ops(pcm, stream,
1546                         stream == SNDRV_PCM_STREAM_PLAYBACK ?
1547                         &snd_usb_playback_ops : &snd_usb_capture_ops);
1548 }