ALSA: usb-audio: refactor code
[linux-2.6.git] / sound / usb / urb.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/init.h>
19 #include <linux/usb.h>
20 #include <linux/usb/audio.h>
21
22 #include <sound/core.h>
23 #include <sound/pcm.h>
24
25 #include "usbaudio.h"
26 #include "helper.h"
27 #include "card.h"
28 #include "urb.h"
29 #include "pcm.h"
30
31 /*
32  * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
33  * this will overflow at approx 524 kHz
34  */
35 static inline unsigned get_usb_full_speed_rate(unsigned int rate)
36 {
37         return ((rate << 13) + 62) / 125;
38 }
39
40 /*
41  * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
42  * this will overflow at approx 4 MHz
43  */
44 static inline unsigned get_usb_high_speed_rate(unsigned int rate)
45 {
46         return ((rate << 10) + 62) / 125;
47 }
48
49 /*
50  * unlink active urbs.
51  */
52 static int deactivate_urbs(struct snd_usb_substream *subs, int force, int can_sleep)
53 {
54         struct snd_usb_audio *chip = subs->stream->chip;
55         unsigned int i;
56         int async;
57
58         subs->running = 0;
59
60         if (!force && subs->stream->chip->shutdown) /* to be sure... */
61                 return -EBADFD;
62
63         async = !can_sleep && chip->async_unlink;
64
65         if (!async && in_interrupt())
66                 return 0;
67
68         for (i = 0; i < subs->nurbs; i++) {
69                 if (test_bit(i, &subs->active_mask)) {
70                         if (!test_and_set_bit(i, &subs->unlink_mask)) {
71                                 struct urb *u = subs->dataurb[i].urb;
72                                 if (async)
73                                         usb_unlink_urb(u);
74                                 else
75                                         usb_kill_urb(u);
76                         }
77                 }
78         }
79         if (subs->syncpipe) {
80                 for (i = 0; i < SYNC_URBS; i++) {
81                         if (test_bit(i+16, &subs->active_mask)) {
82                                 if (!test_and_set_bit(i+16, &subs->unlink_mask)) {
83                                         struct urb *u = subs->syncurb[i].urb;
84                                         if (async)
85                                                 usb_unlink_urb(u);
86                                         else
87                                                 usb_kill_urb(u);
88                                 }
89                         }
90                 }
91         }
92         return 0;
93 }
94
95
96 /*
97  * release a urb data
98  */
99 static void release_urb_ctx(struct snd_urb_ctx *u)
100 {
101         if (u->urb) {
102                 if (u->buffer_size)
103                         usb_buffer_free(u->subs->dev, u->buffer_size,
104                                         u->urb->transfer_buffer,
105                                         u->urb->transfer_dma);
106                 usb_free_urb(u->urb);
107                 u->urb = NULL;
108         }
109 }
110
111 /*
112  *  wait until all urbs are processed.
113  */
114 static int wait_clear_urbs(struct snd_usb_substream *subs)
115 {
116         unsigned long end_time = jiffies + msecs_to_jiffies(1000);
117         unsigned int i;
118         int alive;
119
120         do {
121                 alive = 0;
122                 for (i = 0; i < subs->nurbs; i++) {
123                         if (test_bit(i, &subs->active_mask))
124                                 alive++;
125                 }
126                 if (subs->syncpipe) {
127                         for (i = 0; i < SYNC_URBS; i++) {
128                                 if (test_bit(i + 16, &subs->active_mask))
129                                         alive++;
130                         }
131                 }
132                 if (! alive)
133                         break;
134                 schedule_timeout_uninterruptible(1);
135         } while (time_before(jiffies, end_time));
136         if (alive)
137                 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
138         return 0;
139 }
140
141 /*
142  * release a substream
143  */
144 void snd_usb_release_substream_urbs(struct snd_usb_substream *subs, int force)
145 {
146         int i;
147
148         /* stop urbs (to be sure) */
149         deactivate_urbs(subs, force, 1);
150         wait_clear_urbs(subs);
151
152         for (i = 0; i < MAX_URBS; i++)
153                 release_urb_ctx(&subs->dataurb[i]);
154         for (i = 0; i < SYNC_URBS; i++)
155                 release_urb_ctx(&subs->syncurb[i]);
156         usb_buffer_free(subs->dev, SYNC_URBS * 4,
157                         subs->syncbuf, subs->sync_dma);
158         subs->syncbuf = NULL;
159         subs->nurbs = 0;
160 }
161
162 /*
163  * complete callback from data urb
164  */
165 static void snd_complete_urb(struct urb *urb)
166 {
167         struct snd_urb_ctx *ctx = urb->context;
168         struct snd_usb_substream *subs = ctx->subs;
169         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
170         int err = 0;
171
172         if ((subs->running && subs->ops.retire(subs, substream->runtime, urb)) ||
173             !subs->running || /* can be stopped during retire callback */
174             (err = subs->ops.prepare(subs, substream->runtime, urb)) < 0 ||
175             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
176                 clear_bit(ctx->index, &subs->active_mask);
177                 if (err < 0) {
178                         snd_printd(KERN_ERR "cannot submit urb (err = %d)\n", err);
179                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
180                 }
181         }
182 }
183
184
185 /*
186  * complete callback from sync urb
187  */
188 static void snd_complete_sync_urb(struct urb *urb)
189 {
190         struct snd_urb_ctx *ctx = urb->context;
191         struct snd_usb_substream *subs = ctx->subs;
192         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
193         int err = 0;
194
195         if ((subs->running && subs->ops.retire_sync(subs, substream->runtime, urb)) ||
196             !subs->running || /* can be stopped during retire callback */
197             (err = subs->ops.prepare_sync(subs, substream->runtime, urb)) < 0 ||
198             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
199                 clear_bit(ctx->index + 16, &subs->active_mask);
200                 if (err < 0) {
201                         snd_printd(KERN_ERR "cannot submit sync urb (err = %d)\n", err);
202                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
203                 }
204         }
205 }
206
207
208 /*
209  * initialize a substream for plaback/capture
210  */
211 int snd_usb_init_substream_urbs(struct snd_usb_substream *subs,
212                                 unsigned int period_bytes,
213                                 unsigned int rate,
214                                 unsigned int frame_bits)
215 {
216         unsigned int maxsize, i;
217         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
218         unsigned int urb_packs, total_packs, packs_per_ms;
219         struct snd_usb_audio *chip = subs->stream->chip;
220
221         /* calculate the frequency in 16.16 format */
222         if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
223                 subs->freqn = get_usb_full_speed_rate(rate);
224         else
225                 subs->freqn = get_usb_high_speed_rate(rate);
226         subs->freqm = subs->freqn;
227         /* calculate max. frequency */
228         if (subs->maxpacksize) {
229                 /* whatever fits into a max. size packet */
230                 maxsize = subs->maxpacksize;
231                 subs->freqmax = (maxsize / (frame_bits >> 3))
232                                 << (16 - subs->datainterval);
233         } else {
234                 /* no max. packet size: just take 25% higher than nominal */
235                 subs->freqmax = subs->freqn + (subs->freqn >> 2);
236                 maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3))
237                                 >> (16 - subs->datainterval);
238         }
239         subs->phase = 0;
240
241         if (subs->fill_max)
242                 subs->curpacksize = subs->maxpacksize;
243         else
244                 subs->curpacksize = maxsize;
245
246         if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH)
247                 packs_per_ms = 8 >> subs->datainterval;
248         else
249                 packs_per_ms = 1;
250
251         if (is_playback) {
252                 urb_packs = max(chip->nrpacks, 1);
253                 urb_packs = min(urb_packs, (unsigned int)MAX_PACKS);
254         } else
255                 urb_packs = 1;
256         urb_packs *= packs_per_ms;
257         if (subs->syncpipe)
258                 urb_packs = min(urb_packs, 1U << subs->syncinterval);
259
260         /* decide how many packets to be used */
261         if (is_playback) {
262                 unsigned int minsize, maxpacks;
263                 /* determine how small a packet can be */
264                 minsize = (subs->freqn >> (16 - subs->datainterval))
265                           * (frame_bits >> 3);
266                 /* with sync from device, assume it can be 12% lower */
267                 if (subs->syncpipe)
268                         minsize -= minsize >> 3;
269                 minsize = max(minsize, 1u);
270                 total_packs = (period_bytes + minsize - 1) / minsize;
271                 /* we need at least two URBs for queueing */
272                 if (total_packs < 2) {
273                         total_packs = 2;
274                 } else {
275                         /* and we don't want too long a queue either */
276                         maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
277                         total_packs = min(total_packs, maxpacks);
278                 }
279         } else {
280                 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
281                         urb_packs >>= 1;
282                 total_packs = MAX_URBS * urb_packs;
283         }
284         subs->nurbs = (total_packs + urb_packs - 1) / urb_packs;
285         if (subs->nurbs > MAX_URBS) {
286                 /* too much... */
287                 subs->nurbs = MAX_URBS;
288                 total_packs = MAX_URBS * urb_packs;
289         } else if (subs->nurbs < 2) {
290                 /* too little - we need at least two packets
291                  * to ensure contiguous playback/capture
292                  */
293                 subs->nurbs = 2;
294         }
295
296         /* allocate and initialize data urbs */
297         for (i = 0; i < subs->nurbs; i++) {
298                 struct snd_urb_ctx *u = &subs->dataurb[i];
299                 u->index = i;
300                 u->subs = subs;
301                 u->packets = (i + 1) * total_packs / subs->nurbs
302                         - i * total_packs / subs->nurbs;
303                 u->buffer_size = maxsize * u->packets;
304                 if (subs->fmt_type == UAC_FORMAT_TYPE_II)
305                         u->packets++; /* for transfer delimiter */
306                 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
307                 if (!u->urb)
308                         goto out_of_memory;
309                 u->urb->transfer_buffer =
310                         usb_buffer_alloc(subs->dev, u->buffer_size, GFP_KERNEL,
311                                          &u->urb->transfer_dma);
312                 if (!u->urb->transfer_buffer)
313                         goto out_of_memory;
314                 u->urb->pipe = subs->datapipe;
315                 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
316                 u->urb->interval = 1 << subs->datainterval;
317                 u->urb->context = u;
318                 u->urb->complete = snd_complete_urb;
319         }
320
321         if (subs->syncpipe) {
322                 /* allocate and initialize sync urbs */
323                 subs->syncbuf = usb_buffer_alloc(subs->dev, SYNC_URBS * 4,
324                                                  GFP_KERNEL, &subs->sync_dma);
325                 if (!subs->syncbuf)
326                         goto out_of_memory;
327                 for (i = 0; i < SYNC_URBS; i++) {
328                         struct snd_urb_ctx *u = &subs->syncurb[i];
329                         u->index = i;
330                         u->subs = subs;
331                         u->packets = 1;
332                         u->urb = usb_alloc_urb(1, GFP_KERNEL);
333                         if (!u->urb)
334                                 goto out_of_memory;
335                         u->urb->transfer_buffer = subs->syncbuf + i * 4;
336                         u->urb->transfer_dma = subs->sync_dma + i * 4;
337                         u->urb->transfer_buffer_length = 4;
338                         u->urb->pipe = subs->syncpipe;
339                         u->urb->transfer_flags = URB_ISO_ASAP |
340                                                  URB_NO_TRANSFER_DMA_MAP;
341                         u->urb->number_of_packets = 1;
342                         u->urb->interval = 1 << subs->syncinterval;
343                         u->urb->context = u;
344                         u->urb->complete = snd_complete_sync_urb;
345                 }
346         }
347         return 0;
348
349 out_of_memory:
350         snd_usb_release_substream_urbs(subs, 0);
351         return -ENOMEM;
352 }
353
354 /*
355  * prepare urb for full speed capture sync pipe
356  *
357  * fill the length and offset of each urb descriptor.
358  * the fixed 10.14 frequency is passed through the pipe.
359  */
360 static int prepare_capture_sync_urb(struct snd_usb_substream *subs,
361                                     struct snd_pcm_runtime *runtime,
362                                     struct urb *urb)
363 {
364         unsigned char *cp = urb->transfer_buffer;
365         struct snd_urb_ctx *ctx = urb->context;
366
367         urb->dev = ctx->subs->dev; /* we need to set this at each time */
368         urb->iso_frame_desc[0].length = 3;
369         urb->iso_frame_desc[0].offset = 0;
370         cp[0] = subs->freqn >> 2;
371         cp[1] = subs->freqn >> 10;
372         cp[2] = subs->freqn >> 18;
373         return 0;
374 }
375
376 /*
377  * prepare urb for high speed capture sync pipe
378  *
379  * fill the length and offset of each urb descriptor.
380  * the fixed 12.13 frequency is passed as 16.16 through the pipe.
381  */
382 static int prepare_capture_sync_urb_hs(struct snd_usb_substream *subs,
383                                        struct snd_pcm_runtime *runtime,
384                                        struct urb *urb)
385 {
386         unsigned char *cp = urb->transfer_buffer;
387         struct snd_urb_ctx *ctx = urb->context;
388
389         urb->dev = ctx->subs->dev; /* we need to set this at each time */
390         urb->iso_frame_desc[0].length = 4;
391         urb->iso_frame_desc[0].offset = 0;
392         cp[0] = subs->freqn;
393         cp[1] = subs->freqn >> 8;
394         cp[2] = subs->freqn >> 16;
395         cp[3] = subs->freqn >> 24;
396         return 0;
397 }
398
399 /*
400  * process after capture sync complete
401  * - nothing to do
402  */
403 static int retire_capture_sync_urb(struct snd_usb_substream *subs,
404                                    struct snd_pcm_runtime *runtime,
405                                    struct urb *urb)
406 {
407         return 0;
408 }
409
410 /*
411  * prepare urb for capture data pipe
412  *
413  * fill the offset and length of each descriptor.
414  *
415  * we use a temporary buffer to write the captured data.
416  * since the length of written data is determined by host, we cannot
417  * write onto the pcm buffer directly...  the data is thus copied
418  * later at complete callback to the global buffer.
419  */
420 static int prepare_capture_urb(struct snd_usb_substream *subs,
421                                struct snd_pcm_runtime *runtime,
422                                struct urb *urb)
423 {
424         int i, offs;
425         struct snd_urb_ctx *ctx = urb->context;
426
427         offs = 0;
428         urb->dev = ctx->subs->dev; /* we need to set this at each time */
429         for (i = 0; i < ctx->packets; i++) {
430                 urb->iso_frame_desc[i].offset = offs;
431                 urb->iso_frame_desc[i].length = subs->curpacksize;
432                 offs += subs->curpacksize;
433         }
434         urb->transfer_buffer_length = offs;
435         urb->number_of_packets = ctx->packets;
436         return 0;
437 }
438
439 /*
440  * process after capture complete
441  *
442  * copy the data from each desctiptor to the pcm buffer, and
443  * update the current position.
444  */
445 static int retire_capture_urb(struct snd_usb_substream *subs,
446                               struct snd_pcm_runtime *runtime,
447                               struct urb *urb)
448 {
449         unsigned long flags;
450         unsigned char *cp;
451         int i;
452         unsigned int stride, frames, bytes, oldptr;
453         int period_elapsed = 0;
454
455         stride = runtime->frame_bits >> 3;
456
457         for (i = 0; i < urb->number_of_packets; i++) {
458                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
459                 if (urb->iso_frame_desc[i].status) {
460                         snd_printd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
461                         // continue;
462                 }
463                 bytes = urb->iso_frame_desc[i].actual_length;
464                 frames = bytes / stride;
465                 if (!subs->txfr_quirk)
466                         bytes = frames * stride;
467                 if (bytes % (runtime->sample_bits >> 3) != 0) {
468 #ifdef CONFIG_SND_DEBUG_VERBOSE
469                         int oldbytes = bytes;
470 #endif
471                         bytes = frames * stride;
472                         snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
473                                                         oldbytes, bytes);
474                 }
475                 /* update the current pointer */
476                 spin_lock_irqsave(&subs->lock, flags);
477                 oldptr = subs->hwptr_done;
478                 subs->hwptr_done += bytes;
479                 if (subs->hwptr_done >= runtime->buffer_size * stride)
480                         subs->hwptr_done -= runtime->buffer_size * stride;
481                 frames = (bytes + (oldptr % stride)) / stride;
482                 subs->transfer_done += frames;
483                 if (subs->transfer_done >= runtime->period_size) {
484                         subs->transfer_done -= runtime->period_size;
485                         period_elapsed = 1;
486                 }
487                 spin_unlock_irqrestore(&subs->lock, flags);
488                 /* copy a data chunk */
489                 if (oldptr + bytes > runtime->buffer_size * stride) {
490                         unsigned int bytes1 =
491                                         runtime->buffer_size * stride - oldptr;
492                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
493                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
494                 } else {
495                         memcpy(runtime->dma_area + oldptr, cp, bytes);
496                 }
497         }
498         if (period_elapsed)
499                 snd_pcm_period_elapsed(subs->pcm_substream);
500         return 0;
501 }
502
503 /*
504  * Process after capture complete when paused.  Nothing to do.
505  */
506 static int retire_paused_capture_urb(struct snd_usb_substream *subs,
507                                      struct snd_pcm_runtime *runtime,
508                                      struct urb *urb)
509 {
510         return 0;
511 }
512
513
514 /*
515  * prepare urb for full speed playback sync pipe
516  *
517  * set up the offset and length to receive the current frequency.
518  */
519
520 static int prepare_playback_sync_urb(struct snd_usb_substream *subs,
521                                      struct snd_pcm_runtime *runtime,
522                                      struct urb *urb)
523 {
524         struct snd_urb_ctx *ctx = urb->context;
525
526         urb->dev = ctx->subs->dev; /* we need to set this at each time */
527         urb->iso_frame_desc[0].length = 3;
528         urb->iso_frame_desc[0].offset = 0;
529         return 0;
530 }
531
532 /*
533  * prepare urb for high speed playback sync pipe
534  *
535  * set up the offset and length to receive the current frequency.
536  */
537
538 static int prepare_playback_sync_urb_hs(struct snd_usb_substream *subs,
539                                         struct snd_pcm_runtime *runtime,
540                                         struct urb *urb)
541 {
542         struct snd_urb_ctx *ctx = urb->context;
543
544         urb->dev = ctx->subs->dev; /* we need to set this at each time */
545         urb->iso_frame_desc[0].length = 4;
546         urb->iso_frame_desc[0].offset = 0;
547         return 0;
548 }
549
550 /*
551  * process after full speed playback sync complete
552  *
553  * retrieve the current 10.14 frequency from pipe, and set it.
554  * the value is referred in prepare_playback_urb().
555  */
556 static int retire_playback_sync_urb(struct snd_usb_substream *subs,
557                                     struct snd_pcm_runtime *runtime,
558                                     struct urb *urb)
559 {
560         unsigned int f;
561         unsigned long flags;
562
563         if (urb->iso_frame_desc[0].status == 0 &&
564             urb->iso_frame_desc[0].actual_length == 3) {
565                 f = combine_triple((u8*)urb->transfer_buffer) << 2;
566                 if (f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax) {
567                         spin_lock_irqsave(&subs->lock, flags);
568                         subs->freqm = f;
569                         spin_unlock_irqrestore(&subs->lock, flags);
570                 }
571         }
572
573         return 0;
574 }
575
576 /*
577  * process after high speed playback sync complete
578  *
579  * retrieve the current 12.13 frequency from pipe, and set it.
580  * the value is referred in prepare_playback_urb().
581  */
582 static int retire_playback_sync_urb_hs(struct snd_usb_substream *subs,
583                                        struct snd_pcm_runtime *runtime,
584                                        struct urb *urb)
585 {
586         unsigned int f;
587         unsigned long flags;
588
589         if (urb->iso_frame_desc[0].status == 0 &&
590             urb->iso_frame_desc[0].actual_length == 4) {
591                 f = combine_quad((u8*)urb->transfer_buffer) & 0x0fffffff;
592                 if (f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax) {
593                         spin_lock_irqsave(&subs->lock, flags);
594                         subs->freqm = f;
595                         spin_unlock_irqrestore(&subs->lock, flags);
596                 }
597         }
598
599         return 0;
600 }
601
602 /*
603  * process after E-Mu 0202/0404/Tracker Pre high speed playback sync complete
604  *
605  * These devices return the number of samples per packet instead of the number
606  * of samples per microframe.
607  */
608 static int retire_playback_sync_urb_hs_emu(struct snd_usb_substream *subs,
609                                            struct snd_pcm_runtime *runtime,
610                                            struct urb *urb)
611 {
612         unsigned int f;
613         unsigned long flags;
614
615         if (urb->iso_frame_desc[0].status == 0 &&
616             urb->iso_frame_desc[0].actual_length == 4) {
617                 f = combine_quad((u8*)urb->transfer_buffer) & 0x0fffffff;
618                 f >>= subs->datainterval;
619                 if (f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax) {
620                         spin_lock_irqsave(&subs->lock, flags);
621                         subs->freqm = f;
622                         spin_unlock_irqrestore(&subs->lock, flags);
623                 }
624         }
625
626         return 0;
627 }
628
629 /* determine the number of frames in the next packet */
630 static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs)
631 {
632         if (subs->fill_max)
633                 return subs->maxframesize;
634         else {
635                 subs->phase = (subs->phase & 0xffff)
636                         + (subs->freqm << subs->datainterval);
637                 return min(subs->phase >> 16, subs->maxframesize);
638         }
639 }
640
641 /*
642  * Prepare urb for streaming before playback starts or when paused.
643  *
644  * We don't have any data, so we send silence.
645  */
646 static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
647                                        struct snd_pcm_runtime *runtime,
648                                        struct urb *urb)
649 {
650         unsigned int i, offs, counts;
651         struct snd_urb_ctx *ctx = urb->context;
652         int stride = runtime->frame_bits >> 3;
653
654         offs = 0;
655         urb->dev = ctx->subs->dev;
656         for (i = 0; i < ctx->packets; ++i) {
657                 counts = snd_usb_audio_next_packet_size(subs);
658                 urb->iso_frame_desc[i].offset = offs * stride;
659                 urb->iso_frame_desc[i].length = counts * stride;
660                 offs += counts;
661         }
662         urb->number_of_packets = ctx->packets;
663         urb->transfer_buffer_length = offs * stride;
664         memset(urb->transfer_buffer,
665                subs->cur_audiofmt->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0,
666                offs * stride);
667         return 0;
668 }
669
670 /*
671  * prepare urb for playback data pipe
672  *
673  * Since a URB can handle only a single linear buffer, we must use double
674  * buffering when the data to be transferred overflows the buffer boundary.
675  * To avoid inconsistencies when updating hwptr_done, we use double buffering
676  * for all URBs.
677  */
678 static int prepare_playback_urb(struct snd_usb_substream *subs,
679                                 struct snd_pcm_runtime *runtime,
680                                 struct urb *urb)
681 {
682         int i, stride;
683         unsigned int counts, frames, bytes;
684         unsigned long flags;
685         int period_elapsed = 0;
686         struct snd_urb_ctx *ctx = urb->context;
687
688         stride = runtime->frame_bits >> 3;
689
690         frames = 0;
691         urb->dev = ctx->subs->dev; /* we need to set this at each time */
692         urb->number_of_packets = 0;
693         spin_lock_irqsave(&subs->lock, flags);
694         for (i = 0; i < ctx->packets; i++) {
695                 counts = snd_usb_audio_next_packet_size(subs);
696                 /* set up descriptor */
697                 urb->iso_frame_desc[i].offset = frames * stride;
698                 urb->iso_frame_desc[i].length = counts * stride;
699                 frames += counts;
700                 urb->number_of_packets++;
701                 subs->transfer_done += counts;
702                 if (subs->transfer_done >= runtime->period_size) {
703                         subs->transfer_done -= runtime->period_size;
704                         period_elapsed = 1;
705                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
706                                 if (subs->transfer_done > 0) {
707                                         /* FIXME: fill-max mode is not
708                                          * supported yet */
709                                         frames -= subs->transfer_done;
710                                         counts -= subs->transfer_done;
711                                         urb->iso_frame_desc[i].length =
712                                                 counts * stride;
713                                         subs->transfer_done = 0;
714                                 }
715                                 i++;
716                                 if (i < ctx->packets) {
717                                         /* add a transfer delimiter */
718                                         urb->iso_frame_desc[i].offset =
719                                                 frames * stride;
720                                         urb->iso_frame_desc[i].length = 0;
721                                         urb->number_of_packets++;
722                                 }
723                                 break;
724                         }
725                 }
726                 if (period_elapsed) /* finish at the period boundary */
727                         break;
728         }
729         bytes = frames * stride;
730         if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
731                 /* err, the transferred area goes over buffer boundary. */
732                 unsigned int bytes1 =
733                         runtime->buffer_size * stride - subs->hwptr_done;
734                 memcpy(urb->transfer_buffer,
735                        runtime->dma_area + subs->hwptr_done, bytes1);
736                 memcpy(urb->transfer_buffer + bytes1,
737                        runtime->dma_area, bytes - bytes1);
738         } else {
739                 memcpy(urb->transfer_buffer,
740                        runtime->dma_area + subs->hwptr_done, bytes);
741         }
742         subs->hwptr_done += bytes;
743         if (subs->hwptr_done >= runtime->buffer_size * stride)
744                 subs->hwptr_done -= runtime->buffer_size * stride;
745         runtime->delay += frames;
746         spin_unlock_irqrestore(&subs->lock, flags);
747         urb->transfer_buffer_length = bytes;
748         if (period_elapsed)
749                 snd_pcm_period_elapsed(subs->pcm_substream);
750         return 0;
751 }
752
753 /*
754  * process after playback data complete
755  * - decrease the delay count again
756  */
757 static int retire_playback_urb(struct snd_usb_substream *subs,
758                                struct snd_pcm_runtime *runtime,
759                                struct urb *urb)
760 {
761         unsigned long flags;
762         int stride = runtime->frame_bits >> 3;
763         int processed = urb->transfer_buffer_length / stride;
764
765         spin_lock_irqsave(&subs->lock, flags);
766         if (processed > runtime->delay)
767                 runtime->delay = 0;
768         else
769                 runtime->delay -= processed;
770         spin_unlock_irqrestore(&subs->lock, flags);
771         return 0;
772 }
773
774 static const char *usb_error_string(int err)
775 {
776         switch (err) {
777         case -ENODEV:
778                 return "no device";
779         case -ENOENT:
780                 return "endpoint not enabled";
781         case -EPIPE:
782                 return "endpoint stalled";
783         case -ENOSPC:
784                 return "not enough bandwidth";
785         case -ESHUTDOWN:
786                 return "device disabled";
787         case -EHOSTUNREACH:
788                 return "device suspended";
789         case -EINVAL:
790         case -EAGAIN:
791         case -EFBIG:
792         case -EMSGSIZE:
793                 return "internal error";
794         default:
795                 return "unknown error";
796         }
797 }
798
799 /*
800  * set up and start data/sync urbs
801  */
802 static int start_urbs(struct snd_usb_substream *subs, struct snd_pcm_runtime *runtime)
803 {
804         unsigned int i;
805         int err;
806
807         if (subs->stream->chip->shutdown)
808                 return -EBADFD;
809
810         for (i = 0; i < subs->nurbs; i++) {
811                 if (snd_BUG_ON(!subs->dataurb[i].urb))
812                         return -EINVAL;
813                 if (subs->ops.prepare(subs, runtime, subs->dataurb[i].urb) < 0) {
814                         snd_printk(KERN_ERR "cannot prepare datapipe for urb %d\n", i);
815                         goto __error;
816                 }
817         }
818         if (subs->syncpipe) {
819                 for (i = 0; i < SYNC_URBS; i++) {
820                         if (snd_BUG_ON(!subs->syncurb[i].urb))
821                                 return -EINVAL;
822                         if (subs->ops.prepare_sync(subs, runtime, subs->syncurb[i].urb) < 0) {
823                                 snd_printk(KERN_ERR "cannot prepare syncpipe for urb %d\n", i);
824                                 goto __error;
825                         }
826                 }
827         }
828
829         subs->active_mask = 0;
830         subs->unlink_mask = 0;
831         subs->running = 1;
832         for (i = 0; i < subs->nurbs; i++) {
833                 err = usb_submit_urb(subs->dataurb[i].urb, GFP_ATOMIC);
834                 if (err < 0) {
835                         snd_printk(KERN_ERR "cannot submit datapipe "
836                                    "for urb %d, error %d: %s\n",
837                                    i, err, usb_error_string(err));
838                         goto __error;
839                 }
840                 set_bit(i, &subs->active_mask);
841         }
842         if (subs->syncpipe) {
843                 for (i = 0; i < SYNC_URBS; i++) {
844                         err = usb_submit_urb(subs->syncurb[i].urb, GFP_ATOMIC);
845                         if (err < 0) {
846                                 snd_printk(KERN_ERR "cannot submit syncpipe "
847                                            "for urb %d, error %d: %s\n",
848                                            i, err, usb_error_string(err));
849                                 goto __error;
850                         }
851                         set_bit(i + 16, &subs->active_mask);
852                 }
853         }
854         return 0;
855
856  __error:
857         // snd_pcm_stop(subs->pcm_substream, SNDRV_PCM_STATE_XRUN);
858         deactivate_urbs(subs, 0, 0);
859         return -EPIPE;
860 }
861
862
863 /*
864  */
865 static struct snd_urb_ops audio_urb_ops[2] = {
866         {
867                 .prepare =      prepare_nodata_playback_urb,
868                 .retire =       retire_playback_urb,
869                 .prepare_sync = prepare_playback_sync_urb,
870                 .retire_sync =  retire_playback_sync_urb,
871         },
872         {
873                 .prepare =      prepare_capture_urb,
874                 .retire =       retire_capture_urb,
875                 .prepare_sync = prepare_capture_sync_urb,
876                 .retire_sync =  retire_capture_sync_urb,
877         },
878 };
879
880 static struct snd_urb_ops audio_urb_ops_high_speed[2] = {
881         {
882                 .prepare =      prepare_nodata_playback_urb,
883                 .retire =       retire_playback_urb,
884                 .prepare_sync = prepare_playback_sync_urb_hs,
885                 .retire_sync =  retire_playback_sync_urb_hs,
886         },
887         {
888                 .prepare =      prepare_capture_urb,
889                 .retire =       retire_capture_urb,
890                 .prepare_sync = prepare_capture_sync_urb_hs,
891                 .retire_sync =  retire_capture_sync_urb,
892         },
893 };
894
895 /*
896  * initialize the substream instance.
897  */
898
899 void snd_usb_init_substream(struct snd_usb_stream *as,
900                             int stream, struct audioformat *fp)
901 {
902         struct snd_usb_substream *subs = &as->substream[stream];
903
904         INIT_LIST_HEAD(&subs->fmt_list);
905         spin_lock_init(&subs->lock);
906
907         subs->stream = as;
908         subs->direction = stream;
909         subs->dev = as->chip->dev;
910         subs->txfr_quirk = as->chip->txfr_quirk;
911         if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL) {
912                 subs->ops = audio_urb_ops[stream];
913         } else {
914                 subs->ops = audio_urb_ops_high_speed[stream];
915                 switch (as->chip->usb_id) {
916                 case USB_ID(0x041e, 0x3f02): /* E-Mu 0202 USB */
917                 case USB_ID(0x041e, 0x3f04): /* E-Mu 0404 USB */
918                 case USB_ID(0x041e, 0x3f0a): /* E-Mu Tracker Pre */
919                         subs->ops.retire_sync = retire_playback_sync_urb_hs_emu;
920                         break;
921                 }
922         }
923
924         snd_usb_set_pcm_ops(as->pcm, stream);
925
926         list_add_tail(&fp->list, &subs->fmt_list);
927         subs->formats |= 1ULL << fp->format;
928         subs->endpoint = fp->endpoint;
929         subs->num_formats++;
930         subs->fmt_type = fp->fmt_type;
931 }
932
933 int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream, int cmd)
934 {
935         struct snd_usb_substream *subs = substream->runtime->private_data;
936
937         switch (cmd) {
938         case SNDRV_PCM_TRIGGER_START:
939         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
940                 subs->ops.prepare = prepare_playback_urb;
941                 return 0;
942         case SNDRV_PCM_TRIGGER_STOP:
943                 return deactivate_urbs(subs, 0, 0);
944         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
945                 subs->ops.prepare = prepare_nodata_playback_urb;
946                 return 0;
947         }
948
949         return -EINVAL;
950 }
951
952 int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream, int cmd)
953 {
954         struct snd_usb_substream *subs = substream->runtime->private_data;
955
956         switch (cmd) {
957         case SNDRV_PCM_TRIGGER_START:
958                 subs->ops.retire = retire_capture_urb;
959                 return start_urbs(subs, substream->runtime);
960         case SNDRV_PCM_TRIGGER_STOP:
961                 return deactivate_urbs(subs, 0, 0);
962         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
963                 subs->ops.retire = retire_paused_capture_urb;
964                 return 0;
965         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
966                 subs->ops.retire = retire_capture_urb;
967                 return 0;
968         }
969
970         return -EINVAL;
971 }
972
973 int snd_usb_substream_prepare(struct snd_usb_substream *subs,
974                               struct snd_pcm_runtime *runtime)
975 {
976         /* clear urbs (to be sure) */
977         deactivate_urbs(subs, 0, 1);
978         wait_clear_urbs(subs);
979
980         /* for playback, submit the URBs now; otherwise, the first hwptr_done
981          * updates for all URBs would happen at the same time when starting */
982         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
983                 subs->ops.prepare = prepare_nodata_playback_urb;
984                 return start_urbs(subs, runtime);
985         }
986
987         return 0;
988 }
989