ALSA: usb-audio: Fix regression by disconnection-race-fix patch
[pandora-kernel.git] / sound / usb / endpoint.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
18 #include <linux/gfp.h>
19 #include <linux/init.h>
20 #include <linux/ratelimit.h>
21 #include <linux/usb.h>
22 #include <linux/usb/audio.h>
23
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26
27 #include "usbaudio.h"
28 #include "helper.h"
29 #include "card.h"
30 #include "endpoint.h"
31 #include "pcm.h"
32
33 /*
34  * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
35  * this will overflow at approx 524 kHz
36  */
37 static inline unsigned get_usb_full_speed_rate(unsigned int rate)
38 {
39         return ((rate << 13) + 62) / 125;
40 }
41
42 /*
43  * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
44  * this will overflow at approx 4 MHz
45  */
46 static inline unsigned get_usb_high_speed_rate(unsigned int rate)
47 {
48         return ((rate << 10) + 62) / 125;
49 }
50
51 /*
52  * unlink active urbs.
53  */
54 static int deactivate_urbs(struct snd_usb_substream *subs, int force, int can_sleep)
55 {
56         struct snd_usb_audio *chip = subs->stream->chip;
57         unsigned int i;
58         int async;
59
60         subs->running = 0;
61
62         if (!force && subs->stream->chip->shutdown) /* to be sure... */
63                 return -EBADFD;
64
65         async = !can_sleep && chip->async_unlink;
66
67         if (!async && in_interrupt())
68                 return 0;
69
70         for (i = 0; i < subs->nurbs; i++) {
71                 if (test_bit(i, &subs->active_mask)) {
72                         if (!test_and_set_bit(i, &subs->unlink_mask)) {
73                                 struct urb *u = subs->dataurb[i].urb;
74                                 if (async)
75                                         usb_unlink_urb(u);
76                                 else
77                                         usb_kill_urb(u);
78                         }
79                 }
80         }
81         if (subs->syncpipe) {
82                 for (i = 0; i < SYNC_URBS; i++) {
83                         if (test_bit(i+16, &subs->active_mask)) {
84                                 if (!test_and_set_bit(i+16, &subs->unlink_mask)) {
85                                         struct urb *u = subs->syncurb[i].urb;
86                                         if (async)
87                                                 usb_unlink_urb(u);
88                                         else
89                                                 usb_kill_urb(u);
90                                 }
91                         }
92                 }
93         }
94         return 0;
95 }
96
97
98 /*
99  * release a urb data
100  */
101 static void release_urb_ctx(struct snd_urb_ctx *u)
102 {
103         if (u->urb) {
104                 if (u->buffer_size)
105                         usb_free_coherent(u->subs->dev, u->buffer_size,
106                                         u->urb->transfer_buffer,
107                                         u->urb->transfer_dma);
108                 usb_free_urb(u->urb);
109                 u->urb = NULL;
110         }
111 }
112
113 /*
114  *  wait until all urbs are processed.
115  */
116 static int wait_clear_urbs(struct snd_usb_substream *subs)
117 {
118         unsigned long end_time = jiffies + msecs_to_jiffies(1000);
119         unsigned int i;
120         int alive;
121
122         do {
123                 alive = 0;
124                 for (i = 0; i < subs->nurbs; i++) {
125                         if (test_bit(i, &subs->active_mask))
126                                 alive++;
127                 }
128                 if (subs->syncpipe) {
129                         for (i = 0; i < SYNC_URBS; i++) {
130                                 if (test_bit(i + 16, &subs->active_mask))
131                                         alive++;
132                         }
133                 }
134                 if (! alive)
135                         break;
136                 schedule_timeout_uninterruptible(1);
137         } while (time_before(jiffies, end_time));
138         if (alive)
139                 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
140         return 0;
141 }
142
143 /*
144  * release a substream
145  */
146 void snd_usb_release_substream_urbs(struct snd_usb_substream *subs, int force)
147 {
148         int i;
149
150         /* stop urbs (to be sure) */
151         deactivate_urbs(subs, force, 1);
152         wait_clear_urbs(subs);
153
154         for (i = 0; i < MAX_URBS; i++)
155                 release_urb_ctx(&subs->dataurb[i]);
156         for (i = 0; i < SYNC_URBS; i++)
157                 release_urb_ctx(&subs->syncurb[i]);
158         usb_free_coherent(subs->dev, SYNC_URBS * 4,
159                         subs->syncbuf, subs->sync_dma);
160         subs->syncbuf = NULL;
161         subs->nurbs = 0;
162 }
163
164 /*
165  * complete callback from data urb
166  */
167 static void snd_complete_urb(struct urb *urb)
168 {
169         struct snd_urb_ctx *ctx = urb->context;
170         struct snd_usb_substream *subs = ctx->subs;
171         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
172         int err = 0;
173
174         if ((subs->running && subs->ops.retire(subs, substream->runtime, urb)) ||
175             !subs->running || /* can be stopped during retire callback */
176             (err = subs->ops.prepare(subs, substream->runtime, urb)) < 0 ||
177             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
178                 clear_bit(ctx->index, &subs->active_mask);
179                 if (err < 0) {
180                         snd_printd(KERN_ERR "cannot submit urb (err = %d)\n", err);
181                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
182                 }
183         }
184 }
185
186
187 /*
188  * complete callback from sync urb
189  */
190 static void snd_complete_sync_urb(struct urb *urb)
191 {
192         struct snd_urb_ctx *ctx = urb->context;
193         struct snd_usb_substream *subs = ctx->subs;
194         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
195         int err = 0;
196
197         if ((subs->running && subs->ops.retire_sync(subs, substream->runtime, urb)) ||
198             !subs->running || /* can be stopped during retire callback */
199             (err = subs->ops.prepare_sync(subs, substream->runtime, urb)) < 0 ||
200             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
201                 clear_bit(ctx->index + 16, &subs->active_mask);
202                 if (err < 0) {
203                         snd_printd(KERN_ERR "cannot submit sync urb (err = %d)\n", err);
204                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
205                 }
206         }
207 }
208
209
210 /*
211  * initialize a substream for plaback/capture
212  */
213 int snd_usb_init_substream_urbs(struct snd_usb_substream *subs,
214                                 unsigned int period_bytes,
215                                 unsigned int rate,
216                                 unsigned int frame_bits)
217 {
218         unsigned int maxsize, i;
219         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
220         unsigned int urb_packs, total_packs, packs_per_ms;
221         struct snd_usb_audio *chip = subs->stream->chip;
222
223         /* calculate the frequency in 16.16 format */
224         if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
225                 subs->freqn = get_usb_full_speed_rate(rate);
226         else
227                 subs->freqn = get_usb_high_speed_rate(rate);
228         subs->freqm = subs->freqn;
229         subs->freqshift = INT_MIN;
230         /* calculate max. frequency */
231         if (subs->maxpacksize) {
232                 /* whatever fits into a max. size packet */
233                 maxsize = subs->maxpacksize;
234                 subs->freqmax = (maxsize / (frame_bits >> 3))
235                                 << (16 - subs->datainterval);
236         } else {
237                 /* no max. packet size: just take 25% higher than nominal */
238                 subs->freqmax = subs->freqn + (subs->freqn >> 2);
239                 maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3))
240                                 >> (16 - subs->datainterval);
241         }
242         subs->phase = 0;
243
244         if (subs->fill_max)
245                 subs->curpacksize = subs->maxpacksize;
246         else
247                 subs->curpacksize = maxsize;
248
249         if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL)
250                 packs_per_ms = 8 >> subs->datainterval;
251         else
252                 packs_per_ms = 1;
253
254         if (is_playback) {
255                 urb_packs = max(chip->nrpacks, 1);
256                 urb_packs = min(urb_packs, (unsigned int)MAX_PACKS);
257         } else
258                 urb_packs = 1;
259         urb_packs *= packs_per_ms;
260         if (subs->syncpipe)
261                 urb_packs = min(urb_packs, 1U << subs->syncinterval);
262
263         /* decide how many packets to be used */
264         if (is_playback) {
265                 unsigned int minsize, maxpacks;
266                 /* determine how small a packet can be */
267                 minsize = (subs->freqn >> (16 - subs->datainterval))
268                           * (frame_bits >> 3);
269                 /* with sync from device, assume it can be 12% lower */
270                 if (subs->syncpipe)
271                         minsize -= minsize >> 3;
272                 minsize = max(minsize, 1u);
273                 total_packs = (period_bytes + minsize - 1) / minsize;
274                 /* we need at least two URBs for queueing */
275                 if (total_packs < 2) {
276                         total_packs = 2;
277                 } else {
278                         /* and we don't want too long a queue either */
279                         maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
280                         total_packs = min(total_packs, maxpacks);
281                 }
282         } else {
283                 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
284                         urb_packs >>= 1;
285                 total_packs = MAX_URBS * urb_packs;
286         }
287         subs->nurbs = (total_packs + urb_packs - 1) / urb_packs;
288         if (subs->nurbs > MAX_URBS) {
289                 /* too much... */
290                 subs->nurbs = MAX_URBS;
291                 total_packs = MAX_URBS * urb_packs;
292         } else if (subs->nurbs < 2) {
293                 /* too little - we need at least two packets
294                  * to ensure contiguous playback/capture
295                  */
296                 subs->nurbs = 2;
297         }
298
299         /* allocate and initialize data urbs */
300         for (i = 0; i < subs->nurbs; i++) {
301                 struct snd_urb_ctx *u = &subs->dataurb[i];
302                 u->index = i;
303                 u->subs = subs;
304                 u->packets = (i + 1) * total_packs / subs->nurbs
305                         - i * total_packs / subs->nurbs;
306                 u->buffer_size = maxsize * u->packets;
307                 if (subs->fmt_type == UAC_FORMAT_TYPE_II)
308                         u->packets++; /* for transfer delimiter */
309                 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
310                 if (!u->urb)
311                         goto out_of_memory;
312                 u->urb->transfer_buffer =
313                         usb_alloc_coherent(subs->dev, u->buffer_size,
314                                            GFP_KERNEL, &u->urb->transfer_dma);
315                 if (!u->urb->transfer_buffer)
316                         goto out_of_memory;
317                 u->urb->pipe = subs->datapipe;
318                 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
319                 u->urb->interval = 1 << subs->datainterval;
320                 u->urb->context = u;
321                 u->urb->complete = snd_complete_urb;
322         }
323
324         if (subs->syncpipe) {
325                 /* allocate and initialize sync urbs */
326                 subs->syncbuf = usb_alloc_coherent(subs->dev, SYNC_URBS * 4,
327                                                  GFP_KERNEL, &subs->sync_dma);
328                 if (!subs->syncbuf)
329                         goto out_of_memory;
330                 for (i = 0; i < SYNC_URBS; i++) {
331                         struct snd_urb_ctx *u = &subs->syncurb[i];
332                         u->index = i;
333                         u->subs = subs;
334                         u->packets = 1;
335                         u->urb = usb_alloc_urb(1, GFP_KERNEL);
336                         if (!u->urb)
337                                 goto out_of_memory;
338                         u->urb->transfer_buffer = subs->syncbuf + i * 4;
339                         u->urb->transfer_dma = subs->sync_dma + i * 4;
340                         u->urb->transfer_buffer_length = 4;
341                         u->urb->pipe = subs->syncpipe;
342                         u->urb->transfer_flags = URB_ISO_ASAP |
343                                                  URB_NO_TRANSFER_DMA_MAP;
344                         u->urb->number_of_packets = 1;
345                         u->urb->interval = 1 << subs->syncinterval;
346                         u->urb->context = u;
347                         u->urb->complete = snd_complete_sync_urb;
348                 }
349         }
350         return 0;
351
352 out_of_memory:
353         snd_usb_release_substream_urbs(subs, 0);
354         return -ENOMEM;
355 }
356
357 /*
358  * prepare urb for full speed capture sync pipe
359  *
360  * fill the length and offset of each urb descriptor.
361  * the fixed 10.14 frequency is passed through the pipe.
362  */
363 static int prepare_capture_sync_urb(struct snd_usb_substream *subs,
364                                     struct snd_pcm_runtime *runtime,
365                                     struct urb *urb)
366 {
367         unsigned char *cp = urb->transfer_buffer;
368         struct snd_urb_ctx *ctx = urb->context;
369
370         urb->dev = ctx->subs->dev; /* we need to set this at each time */
371         urb->iso_frame_desc[0].length = 3;
372         urb->iso_frame_desc[0].offset = 0;
373         cp[0] = subs->freqn >> 2;
374         cp[1] = subs->freqn >> 10;
375         cp[2] = subs->freqn >> 18;
376         return 0;
377 }
378
379 /*
380  * prepare urb for high speed capture sync pipe
381  *
382  * fill the length and offset of each urb descriptor.
383  * the fixed 12.13 frequency is passed as 16.16 through the pipe.
384  */
385 static int prepare_capture_sync_urb_hs(struct snd_usb_substream *subs,
386                                        struct snd_pcm_runtime *runtime,
387                                        struct urb *urb)
388 {
389         unsigned char *cp = urb->transfer_buffer;
390         struct snd_urb_ctx *ctx = urb->context;
391
392         urb->dev = ctx->subs->dev; /* we need to set this at each time */
393         urb->iso_frame_desc[0].length = 4;
394         urb->iso_frame_desc[0].offset = 0;
395         cp[0] = subs->freqn;
396         cp[1] = subs->freqn >> 8;
397         cp[2] = subs->freqn >> 16;
398         cp[3] = subs->freqn >> 24;
399         return 0;
400 }
401
402 /*
403  * process after capture sync complete
404  * - nothing to do
405  */
406 static int retire_capture_sync_urb(struct snd_usb_substream *subs,
407                                    struct snd_pcm_runtime *runtime,
408                                    struct urb *urb)
409 {
410         return 0;
411 }
412
413 /*
414  * prepare urb for capture data pipe
415  *
416  * fill the offset and length of each descriptor.
417  *
418  * we use a temporary buffer to write the captured data.
419  * since the length of written data is determined by host, we cannot
420  * write onto the pcm buffer directly...  the data is thus copied
421  * later at complete callback to the global buffer.
422  */
423 static int prepare_capture_urb(struct snd_usb_substream *subs,
424                                struct snd_pcm_runtime *runtime,
425                                struct urb *urb)
426 {
427         int i, offs;
428         struct snd_urb_ctx *ctx = urb->context;
429
430         offs = 0;
431         urb->dev = ctx->subs->dev; /* we need to set this at each time */
432         for (i = 0; i < ctx->packets; i++) {
433                 urb->iso_frame_desc[i].offset = offs;
434                 urb->iso_frame_desc[i].length = subs->curpacksize;
435                 offs += subs->curpacksize;
436         }
437         urb->transfer_buffer_length = offs;
438         urb->number_of_packets = ctx->packets;
439         return 0;
440 }
441
442 /*
443  * process after capture complete
444  *
445  * copy the data from each desctiptor to the pcm buffer, and
446  * update the current position.
447  */
448 static int retire_capture_urb(struct snd_usb_substream *subs,
449                               struct snd_pcm_runtime *runtime,
450                               struct urb *urb)
451 {
452         unsigned long flags;
453         unsigned char *cp;
454         int i;
455         unsigned int stride, frames, bytes, oldptr;
456         int period_elapsed = 0;
457
458         stride = runtime->frame_bits >> 3;
459
460         for (i = 0; i < urb->number_of_packets; i++) {
461                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
462                 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
463                         snd_printdd("frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
464                         // continue;
465                 }
466                 bytes = urb->iso_frame_desc[i].actual_length;
467                 frames = bytes / stride;
468                 if (!subs->txfr_quirk)
469                         bytes = frames * stride;
470                 if (bytes % (runtime->sample_bits >> 3) != 0) {
471 #ifdef CONFIG_SND_DEBUG_VERBOSE
472                         int oldbytes = bytes;
473 #endif
474                         bytes = frames * stride;
475                         snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
476                                                         oldbytes, bytes);
477                 }
478                 /* update the current pointer */
479                 spin_lock_irqsave(&subs->lock, flags);
480                 oldptr = subs->hwptr_done;
481                 subs->hwptr_done += bytes;
482                 if (subs->hwptr_done >= runtime->buffer_size * stride)
483                         subs->hwptr_done -= runtime->buffer_size * stride;
484                 frames = (bytes + (oldptr % stride)) / stride;
485                 subs->transfer_done += frames;
486                 if (subs->transfer_done >= runtime->period_size) {
487                         subs->transfer_done -= runtime->period_size;
488                         period_elapsed = 1;
489                 }
490                 spin_unlock_irqrestore(&subs->lock, flags);
491                 /* copy a data chunk */
492                 if (oldptr + bytes > runtime->buffer_size * stride) {
493                         unsigned int bytes1 =
494                                         runtime->buffer_size * stride - oldptr;
495                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
496                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
497                 } else {
498                         memcpy(runtime->dma_area + oldptr, cp, bytes);
499                 }
500         }
501         if (period_elapsed)
502                 snd_pcm_period_elapsed(subs->pcm_substream);
503         return 0;
504 }
505
506 /*
507  * Process after capture complete when paused.  Nothing to do.
508  */
509 static int retire_paused_capture_urb(struct snd_usb_substream *subs,
510                                      struct snd_pcm_runtime *runtime,
511                                      struct urb *urb)
512 {
513         return 0;
514 }
515
516
517 /*
518  * prepare urb for playback sync pipe
519  *
520  * set up the offset and length to receive the current frequency.
521  */
522 static int prepare_playback_sync_urb(struct snd_usb_substream *subs,
523                                      struct snd_pcm_runtime *runtime,
524                                      struct urb *urb)
525 {
526         struct snd_urb_ctx *ctx = urb->context;
527
528         urb->dev = ctx->subs->dev; /* we need to set this at each time */
529         urb->iso_frame_desc[0].length = min(4u, ctx->subs->syncmaxsize);
530         urb->iso_frame_desc[0].offset = 0;
531         return 0;
532 }
533
534 /*
535  * process after playback sync complete
536  *
537  * Full speed devices report feedback values in 10.14 format as samples per
538  * frame, high speed devices in 16.16 format as samples per microframe.
539  * Because the Audio Class 1 spec was written before USB 2.0, many high speed
540  * devices use a wrong interpretation, some others use an entirely different
541  * format.  Therefore, we cannot predict what format any particular device uses
542  * and must detect it automatically.
543  */
544 static int retire_playback_sync_urb(struct snd_usb_substream *subs,
545                                     struct snd_pcm_runtime *runtime,
546                                     struct urb *urb)
547 {
548         unsigned int f;
549         int shift;
550         unsigned long flags;
551
552         if (urb->iso_frame_desc[0].status != 0 ||
553             urb->iso_frame_desc[0].actual_length < 3)
554                 return 0;
555
556         f = le32_to_cpup(urb->transfer_buffer);
557         if (urb->iso_frame_desc[0].actual_length == 3)
558                 f &= 0x00ffffff;
559         else
560                 f &= 0x0fffffff;
561         if (f == 0)
562                 return 0;
563
564         if (unlikely(subs->freqshift == INT_MIN)) {
565                 /*
566                  * The first time we see a feedback value, determine its format
567                  * by shifting it left or right until it matches the nominal
568                  * frequency value.  This assumes that the feedback does not
569                  * differ from the nominal value more than +50% or -25%.
570                  */
571                 shift = 0;
572                 while (f < subs->freqn - subs->freqn / 4) {
573                         f <<= 1;
574                         shift++;
575                 }
576                 while (f > subs->freqn + subs->freqn / 2) {
577                         f >>= 1;
578                         shift--;
579                 }
580                 subs->freqshift = shift;
581         }
582         else if (subs->freqshift >= 0)
583                 f <<= subs->freqshift;
584         else
585                 f >>= -subs->freqshift;
586
587         if (likely(f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax)) {
588                 /*
589                  * If the frequency looks valid, set it.
590                  * This value is referred to in prepare_playback_urb().
591                  */
592                 spin_lock_irqsave(&subs->lock, flags);
593                 subs->freqm = f;
594                 spin_unlock_irqrestore(&subs->lock, flags);
595         } else {
596                 /*
597                  * Out of range; maybe the shift value is wrong.
598                  * Reset it so that we autodetect again the next time.
599                  */
600                 subs->freqshift = INT_MIN;
601         }
602
603         return 0;
604 }
605
606 /* determine the number of frames in the next packet */
607 static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs)
608 {
609         if (subs->fill_max)
610                 return subs->maxframesize;
611         else {
612                 subs->phase = (subs->phase & 0xffff)
613                         + (subs->freqm << subs->datainterval);
614                 return min(subs->phase >> 16, subs->maxframesize);
615         }
616 }
617
618 /*
619  * Prepare urb for streaming before playback starts or when paused.
620  *
621  * We don't have any data, so we send silence.
622  */
623 static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
624                                        struct snd_pcm_runtime *runtime,
625                                        struct urb *urb)
626 {
627         unsigned int i, offs, counts;
628         struct snd_urb_ctx *ctx = urb->context;
629         int stride = runtime->frame_bits >> 3;
630
631         offs = 0;
632         urb->dev = ctx->subs->dev;
633         for (i = 0; i < ctx->packets; ++i) {
634                 counts = snd_usb_audio_next_packet_size(subs);
635                 urb->iso_frame_desc[i].offset = offs * stride;
636                 urb->iso_frame_desc[i].length = counts * stride;
637                 offs += counts;
638         }
639         urb->number_of_packets = ctx->packets;
640         urb->transfer_buffer_length = offs * stride;
641         memset(urb->transfer_buffer,
642                runtime->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0,
643                offs * stride);
644         return 0;
645 }
646
647 /*
648  * prepare urb for playback data pipe
649  *
650  * Since a URB can handle only a single linear buffer, we must use double
651  * buffering when the data to be transferred overflows the buffer boundary.
652  * To avoid inconsistencies when updating hwptr_done, we use double buffering
653  * for all URBs.
654  */
655 static int prepare_playback_urb(struct snd_usb_substream *subs,
656                                 struct snd_pcm_runtime *runtime,
657                                 struct urb *urb)
658 {
659         int i, stride;
660         unsigned int counts, frames, bytes;
661         unsigned long flags;
662         int period_elapsed = 0;
663         struct snd_urb_ctx *ctx = urb->context;
664
665         stride = runtime->frame_bits >> 3;
666
667         frames = 0;
668         urb->dev = ctx->subs->dev; /* we need to set this at each time */
669         urb->number_of_packets = 0;
670         spin_lock_irqsave(&subs->lock, flags);
671         for (i = 0; i < ctx->packets; i++) {
672                 counts = snd_usb_audio_next_packet_size(subs);
673                 /* set up descriptor */
674                 urb->iso_frame_desc[i].offset = frames * stride;
675                 urb->iso_frame_desc[i].length = counts * stride;
676                 frames += counts;
677                 urb->number_of_packets++;
678                 subs->transfer_done += counts;
679                 if (subs->transfer_done >= runtime->period_size) {
680                         subs->transfer_done -= runtime->period_size;
681                         period_elapsed = 1;
682                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
683                                 if (subs->transfer_done > 0) {
684                                         /* FIXME: fill-max mode is not
685                                          * supported yet */
686                                         frames -= subs->transfer_done;
687                                         counts -= subs->transfer_done;
688                                         urb->iso_frame_desc[i].length =
689                                                 counts * stride;
690                                         subs->transfer_done = 0;
691                                 }
692                                 i++;
693                                 if (i < ctx->packets) {
694                                         /* add a transfer delimiter */
695                                         urb->iso_frame_desc[i].offset =
696                                                 frames * stride;
697                                         urb->iso_frame_desc[i].length = 0;
698                                         urb->number_of_packets++;
699                                 }
700                                 break;
701                         }
702                 }
703                 if (period_elapsed) /* finish at the period boundary */
704                         break;
705         }
706         bytes = frames * stride;
707         if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
708                 /* err, the transferred area goes over buffer boundary. */
709                 unsigned int bytes1 =
710                         runtime->buffer_size * stride - subs->hwptr_done;
711                 memcpy(urb->transfer_buffer,
712                        runtime->dma_area + subs->hwptr_done, bytes1);
713                 memcpy(urb->transfer_buffer + bytes1,
714                        runtime->dma_area, bytes - bytes1);
715         } else {
716                 memcpy(urb->transfer_buffer,
717                        runtime->dma_area + subs->hwptr_done, bytes);
718         }
719         subs->hwptr_done += bytes;
720         if (subs->hwptr_done >= runtime->buffer_size * stride)
721                 subs->hwptr_done -= runtime->buffer_size * stride;
722
723         /* update delay with exact number of samples queued */
724         runtime->delay = subs->last_delay;
725         runtime->delay += frames;
726         subs->last_delay = runtime->delay;
727
728         /* realign last_frame_number */
729         subs->last_frame_number = usb_get_current_frame_number(subs->dev);
730         subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
731
732         spin_unlock_irqrestore(&subs->lock, flags);
733         urb->transfer_buffer_length = bytes;
734         if (period_elapsed)
735                 snd_pcm_period_elapsed(subs->pcm_substream);
736         return 0;
737 }
738
739 /*
740  * process after playback data complete
741  * - decrease the delay count again
742  */
743 static int retire_playback_urb(struct snd_usb_substream *subs,
744                                struct snd_pcm_runtime *runtime,
745                                struct urb *urb)
746 {
747         unsigned long flags;
748         int stride = runtime->frame_bits >> 3;
749         int processed = urb->transfer_buffer_length / stride;
750         int est_delay;
751
752         spin_lock_irqsave(&subs->lock, flags);
753
754         est_delay = snd_usb_pcm_delay(subs, runtime->rate);
755         /* update delay with exact number of samples played */
756         if (processed > subs->last_delay)
757                 subs->last_delay = 0;
758         else
759                 subs->last_delay -= processed;
760         runtime->delay = subs->last_delay;
761
762         /*
763          * Report when delay estimate is off by more than 2ms.
764          * The error should be lower than 2ms since the estimate relies
765          * on two reads of a counter updated every ms.
766          */
767         if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
768                 snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
769                         est_delay, subs->last_delay);
770
771         spin_unlock_irqrestore(&subs->lock, flags);
772         return 0;
773 }
774
775 static const char *usb_error_string(int err)
776 {
777         switch (err) {
778         case -ENODEV:
779                 return "no device";
780         case -ENOENT:
781                 return "endpoint not enabled";
782         case -EPIPE:
783                 return "endpoint stalled";
784         case -ENOSPC:
785                 return "not enough bandwidth";
786         case -ESHUTDOWN:
787                 return "device disabled";
788         case -EHOSTUNREACH:
789                 return "device suspended";
790         case -EINVAL:
791         case -EAGAIN:
792         case -EFBIG:
793         case -EMSGSIZE:
794                 return "internal error";
795         default:
796                 return "unknown error";
797         }
798 }
799
800 /*
801  * set up and start data/sync urbs
802  */
803 static int start_urbs(struct snd_usb_substream *subs, struct snd_pcm_runtime *runtime)
804 {
805         unsigned int i;
806         int err;
807
808         if (subs->stream->chip->shutdown)
809                 return -EBADFD;
810
811         for (i = 0; i < subs->nurbs; i++) {
812                 if (snd_BUG_ON(!subs->dataurb[i].urb))
813                         return -EINVAL;
814                 if (subs->ops.prepare(subs, runtime, subs->dataurb[i].urb) < 0) {
815                         snd_printk(KERN_ERR "cannot prepare datapipe for urb %d\n", i);
816                         goto __error;
817                 }
818         }
819         if (subs->syncpipe) {
820                 for (i = 0; i < SYNC_URBS; i++) {
821                         if (snd_BUG_ON(!subs->syncurb[i].urb))
822                                 return -EINVAL;
823                         if (subs->ops.prepare_sync(subs, runtime, subs->syncurb[i].urb) < 0) {
824                                 snd_printk(KERN_ERR "cannot prepare syncpipe for urb %d\n", i);
825                                 goto __error;
826                         }
827                 }
828         }
829
830         subs->active_mask = 0;
831         subs->unlink_mask = 0;
832         subs->running = 1;
833         for (i = 0; i < subs->nurbs; i++) {
834                 err = usb_submit_urb(subs->dataurb[i].urb, GFP_ATOMIC);
835                 if (err < 0) {
836                         snd_printk(KERN_ERR "cannot submit datapipe "
837                                    "for urb %d, error %d: %s\n",
838                                    i, err, usb_error_string(err));
839                         goto __error;
840                 }
841                 set_bit(i, &subs->active_mask);
842         }
843         if (subs->syncpipe) {
844                 for (i = 0; i < SYNC_URBS; i++) {
845                         err = usb_submit_urb(subs->syncurb[i].urb, GFP_ATOMIC);
846                         if (err < 0) {
847                                 snd_printk(KERN_ERR "cannot submit syncpipe "
848                                            "for urb %d, error %d: %s\n",
849                                            i, err, usb_error_string(err));
850                                 goto __error;
851                         }
852                         set_bit(i + 16, &subs->active_mask);
853                 }
854         }
855         return 0;
856
857  __error:
858         // snd_pcm_stop(subs->pcm_substream, SNDRV_PCM_STATE_XRUN);
859         deactivate_urbs(subs, 0, 0);
860         return -EPIPE;
861 }
862
863
864 /*
865  */
866 static struct snd_urb_ops audio_urb_ops[2] = {
867         {
868                 .prepare =      prepare_nodata_playback_urb,
869                 .retire =       retire_playback_urb,
870                 .prepare_sync = prepare_playback_sync_urb,
871                 .retire_sync =  retire_playback_sync_urb,
872         },
873         {
874                 .prepare =      prepare_capture_urb,
875                 .retire =       retire_capture_urb,
876                 .prepare_sync = prepare_capture_sync_urb,
877                 .retire_sync =  retire_capture_sync_urb,
878         },
879 };
880
881 /*
882  * initialize the substream instance.
883  */
884
885 void snd_usb_init_substream(struct snd_usb_stream *as,
886                             int stream, struct audioformat *fp)
887 {
888         struct snd_usb_substream *subs = &as->substream[stream];
889
890         INIT_LIST_HEAD(&subs->fmt_list);
891         spin_lock_init(&subs->lock);
892
893         subs->stream = as;
894         subs->direction = stream;
895         subs->dev = as->chip->dev;
896         subs->txfr_quirk = as->chip->txfr_quirk;
897         subs->ops = audio_urb_ops[stream];
898         subs->speed = snd_usb_get_speed(subs->dev);
899         if (subs->speed >= USB_SPEED_HIGH)
900                 subs->ops.prepare_sync = prepare_capture_sync_urb_hs;
901
902         snd_usb_set_pcm_ops(as->pcm, stream);
903
904         list_add_tail(&fp->list, &subs->fmt_list);
905         subs->formats |= fp->formats;
906         subs->endpoint = fp->endpoint;
907         subs->num_formats++;
908         subs->fmt_type = fp->fmt_type;
909 }
910
911 int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream, int cmd)
912 {
913         struct snd_usb_substream *subs = substream->runtime->private_data;
914
915         switch (cmd) {
916         case SNDRV_PCM_TRIGGER_START:
917         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
918                 subs->ops.prepare = prepare_playback_urb;
919                 return 0;
920         case SNDRV_PCM_TRIGGER_STOP:
921                 return deactivate_urbs(subs, 0, 0);
922         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
923                 subs->ops.prepare = prepare_nodata_playback_urb;
924                 return 0;
925         }
926
927         return -EINVAL;
928 }
929
930 int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream, int cmd)
931 {
932         struct snd_usb_substream *subs = substream->runtime->private_data;
933
934         switch (cmd) {
935         case SNDRV_PCM_TRIGGER_START:
936                 subs->ops.retire = retire_capture_urb;
937                 return start_urbs(subs, substream->runtime);
938         case SNDRV_PCM_TRIGGER_STOP:
939                 return deactivate_urbs(subs, 0, 0);
940         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
941                 subs->ops.retire = retire_paused_capture_urb;
942                 return 0;
943         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
944                 subs->ops.retire = retire_capture_urb;
945                 return 0;
946         }
947
948         return -EINVAL;
949 }
950
951 int snd_usb_substream_prepare(struct snd_usb_substream *subs,
952                               struct snd_pcm_runtime *runtime)
953 {
954         /* clear urbs (to be sure) */
955         deactivate_urbs(subs, 0, 1);
956         wait_clear_urbs(subs);
957
958         /* for playback, submit the URBs now; otherwise, the first hwptr_done
959          * updates for all URBs would happen at the same time when starting */
960         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
961                 subs->ops.prepare = prepare_nodata_playback_urb;
962                 return start_urbs(subs, runtime);
963         }
964
965         return 0;
966 }
967