1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Line 6 Linux USB driver
4 *
5 * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
6 */
7
8 #include <linux/slab.h>
9 #include <linux/export.h>
10 #include <sound/core.h>
11 #include <sound/control.h>
12 #include <sound/pcm.h>
13 #include <sound/pcm_params.h>
14
15 #include "capture.h"
16 #include "driver.h"
17 #include "playback.h"
18
19 /* impulse response volume controls */
snd_line6_impulse_volume_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)20 static int snd_line6_impulse_volume_info(struct snd_kcontrol *kcontrol,
21 struct snd_ctl_elem_info *uinfo)
22 {
23 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
24 uinfo->count = 1;
25 uinfo->value.integer.min = 0;
26 uinfo->value.integer.max = 255;
27 return 0;
28 }
29
snd_line6_impulse_volume_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)30 static int snd_line6_impulse_volume_get(struct snd_kcontrol *kcontrol,
31 struct snd_ctl_elem_value *ucontrol)
32 {
33 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
34
35 ucontrol->value.integer.value[0] = line6pcm->impulse_volume;
36 return 0;
37 }
38
snd_line6_impulse_volume_put(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)39 static int snd_line6_impulse_volume_put(struct snd_kcontrol *kcontrol,
40 struct snd_ctl_elem_value *ucontrol)
41 {
42 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
43 int value = ucontrol->value.integer.value[0];
44 int err;
45
46 if (line6pcm->impulse_volume == value)
47 return 0;
48
49 line6pcm->impulse_volume = value;
50 if (value > 0) {
51 err = line6_pcm_acquire(line6pcm, LINE6_STREAM_IMPULSE, true);
52 if (err < 0) {
53 line6pcm->impulse_volume = 0;
54 return err;
55 }
56 } else {
57 line6_pcm_release(line6pcm, LINE6_STREAM_IMPULSE);
58 }
59 return 1;
60 }
61
62 /* impulse response period controls */
snd_line6_impulse_period_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)63 static int snd_line6_impulse_period_info(struct snd_kcontrol *kcontrol,
64 struct snd_ctl_elem_info *uinfo)
65 {
66 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
67 uinfo->count = 1;
68 uinfo->value.integer.min = 0;
69 uinfo->value.integer.max = 2000;
70 return 0;
71 }
72
snd_line6_impulse_period_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)73 static int snd_line6_impulse_period_get(struct snd_kcontrol *kcontrol,
74 struct snd_ctl_elem_value *ucontrol)
75 {
76 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
77
78 ucontrol->value.integer.value[0] = line6pcm->impulse_period;
79 return 0;
80 }
81
snd_line6_impulse_period_put(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)82 static int snd_line6_impulse_period_put(struct snd_kcontrol *kcontrol,
83 struct snd_ctl_elem_value *ucontrol)
84 {
85 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
86 int value = ucontrol->value.integer.value[0];
87
88 if (line6pcm->impulse_period == value)
89 return 0;
90
91 line6pcm->impulse_period = value;
92 return 1;
93 }
94
95 /*
96 Unlink all currently active URBs.
97 */
line6_unlink_audio_urbs(struct snd_line6_pcm * line6pcm,struct line6_pcm_stream * pcms)98 static void line6_unlink_audio_urbs(struct snd_line6_pcm *line6pcm,
99 struct line6_pcm_stream *pcms)
100 {
101 int i;
102
103 for (i = 0; i < line6pcm->line6->iso_buffers; i++) {
104 if (test_bit(i, &pcms->active_urbs)) {
105 if (!test_and_set_bit(i, &pcms->unlink_urbs))
106 usb_unlink_urb(pcms->urbs[i]);
107 }
108 }
109 }
110
111 /*
112 Wait until unlinking of all currently active URBs has been finished.
113 */
line6_wait_clear_audio_urbs(struct snd_line6_pcm * line6pcm,struct line6_pcm_stream * pcms)114 static void line6_wait_clear_audio_urbs(struct snd_line6_pcm *line6pcm,
115 struct line6_pcm_stream *pcms)
116 {
117 int timeout = HZ;
118 int i;
119 int alive;
120
121 do {
122 alive = 0;
123 for (i = 0; i < line6pcm->line6->iso_buffers; i++) {
124 if (test_bit(i, &pcms->active_urbs))
125 alive++;
126 }
127 if (!alive)
128 break;
129 set_current_state(TASK_UNINTERRUPTIBLE);
130 schedule_timeout(1);
131 } while (--timeout > 0);
132 if (alive)
133 dev_err(line6pcm->line6->ifcdev,
134 "timeout: still %d active urbs..\n", alive);
135 }
136
137 static inline struct line6_pcm_stream *
get_stream(struct snd_line6_pcm * line6pcm,int direction)138 get_stream(struct snd_line6_pcm *line6pcm, int direction)
139 {
140 return (direction == SNDRV_PCM_STREAM_PLAYBACK) ?
141 &line6pcm->out : &line6pcm->in;
142 }
143
144 /* allocate a buffer if not opened yet;
145 * call this in line6pcm.state_mutex
146 */
line6_buffer_acquire(struct snd_line6_pcm * line6pcm,struct line6_pcm_stream * pstr,int direction,int type)147 static int line6_buffer_acquire(struct snd_line6_pcm *line6pcm,
148 struct line6_pcm_stream *pstr, int direction, int type)
149 {
150 const int pkt_size =
151 (direction == SNDRV_PCM_STREAM_PLAYBACK) ?
152 line6pcm->max_packet_size_out :
153 line6pcm->max_packet_size_in;
154
155 /* Invoked multiple times in a row so allocate once only */
156 if (!test_and_set_bit(type, &pstr->opened) && !pstr->buffer) {
157 pstr->buffer =
158 kmalloc(array3_size(line6pcm->line6->iso_buffers,
159 LINE6_ISO_PACKETS, pkt_size),
160 GFP_KERNEL);
161 if (!pstr->buffer)
162 return -ENOMEM;
163 }
164 return 0;
165 }
166
167 /* free a buffer if all streams are closed;
168 * call this in line6pcm.state_mutex
169 */
line6_buffer_release(struct snd_line6_pcm * line6pcm,struct line6_pcm_stream * pstr,int type)170 static void line6_buffer_release(struct snd_line6_pcm *line6pcm,
171 struct line6_pcm_stream *pstr, int type)
172 {
173 clear_bit(type, &pstr->opened);
174 if (!pstr->opened) {
175 line6_wait_clear_audio_urbs(line6pcm, pstr);
176 kfree(pstr->buffer);
177 pstr->buffer = NULL;
178 }
179 }
180
181 /* start a PCM stream */
line6_stream_start(struct snd_line6_pcm * line6pcm,int direction,int type)182 static int line6_stream_start(struct snd_line6_pcm *line6pcm, int direction,
183 int type)
184 {
185 unsigned long flags;
186 struct line6_pcm_stream *pstr = get_stream(line6pcm, direction);
187 int ret = 0;
188
189 spin_lock_irqsave(&pstr->lock, flags);
190 if (!test_and_set_bit(type, &pstr->running) &&
191 !(pstr->active_urbs || pstr->unlink_urbs)) {
192 pstr->count = 0;
193 /* Submit all currently available URBs */
194 if (direction == SNDRV_PCM_STREAM_PLAYBACK)
195 ret = line6_submit_audio_out_all_urbs(line6pcm);
196 else
197 ret = line6_submit_audio_in_all_urbs(line6pcm);
198 }
199
200 if (ret < 0)
201 clear_bit(type, &pstr->running);
202 spin_unlock_irqrestore(&pstr->lock, flags);
203 return ret;
204 }
205
206 /* stop a PCM stream; this doesn't sync with the unlinked URBs */
line6_stream_stop(struct snd_line6_pcm * line6pcm,int direction,int type)207 static void line6_stream_stop(struct snd_line6_pcm *line6pcm, int direction,
208 int type)
209 {
210 unsigned long flags;
211 struct line6_pcm_stream *pstr = get_stream(line6pcm, direction);
212
213 spin_lock_irqsave(&pstr->lock, flags);
214 clear_bit(type, &pstr->running);
215 if (!pstr->running) {
216 spin_unlock_irqrestore(&pstr->lock, flags);
217 line6_unlink_audio_urbs(line6pcm, pstr);
218 spin_lock_irqsave(&pstr->lock, flags);
219 if (direction == SNDRV_PCM_STREAM_CAPTURE) {
220 line6pcm->prev_fbuf = NULL;
221 line6pcm->prev_fsize = 0;
222 }
223 }
224 spin_unlock_irqrestore(&pstr->lock, flags);
225 }
226
227 /* common PCM trigger callback */
snd_line6_trigger(struct snd_pcm_substream * substream,int cmd)228 int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd)
229 {
230 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
231 struct snd_pcm_substream *s;
232 int err;
233
234 clear_bit(LINE6_FLAG_PREPARED, &line6pcm->flags);
235
236 snd_pcm_group_for_each_entry(s, substream) {
237 if (s->pcm->card != substream->pcm->card)
238 continue;
239
240 switch (cmd) {
241 case SNDRV_PCM_TRIGGER_START:
242 case SNDRV_PCM_TRIGGER_RESUME:
243 if (s->stream == SNDRV_PCM_STREAM_CAPTURE &&
244 (line6pcm->line6->properties->capabilities &
245 LINE6_CAP_IN_NEEDS_OUT)) {
246 err = line6_stream_start(line6pcm, SNDRV_PCM_STREAM_PLAYBACK,
247 LINE6_STREAM_CAPTURE_HELPER);
248 if (err < 0)
249 return err;
250 }
251 err = line6_stream_start(line6pcm, s->stream,
252 LINE6_STREAM_PCM);
253 if (err < 0)
254 return err;
255 break;
256
257 case SNDRV_PCM_TRIGGER_STOP:
258 case SNDRV_PCM_TRIGGER_SUSPEND:
259 if (s->stream == SNDRV_PCM_STREAM_CAPTURE &&
260 (line6pcm->line6->properties->capabilities &
261 LINE6_CAP_IN_NEEDS_OUT)) {
262 line6_stream_stop(line6pcm, SNDRV_PCM_STREAM_PLAYBACK,
263 LINE6_STREAM_CAPTURE_HELPER);
264 }
265 line6_stream_stop(line6pcm, s->stream,
266 LINE6_STREAM_PCM);
267 break;
268
269 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
270 if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
271 return -EINVAL;
272 set_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags);
273 break;
274
275 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
276 if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
277 return -EINVAL;
278 clear_bit(LINE6_FLAG_PAUSE_PLAYBACK, &line6pcm->flags);
279 break;
280
281 default:
282 return -EINVAL;
283 }
284 }
285
286 return 0;
287 }
288
289 /* common PCM pointer callback */
snd_line6_pointer(struct snd_pcm_substream * substream)290 snd_pcm_uframes_t snd_line6_pointer(struct snd_pcm_substream *substream)
291 {
292 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
293 struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
294
295 return pstr->pos_done;
296 }
297
298 /* Acquire and optionally start duplex streams:
299 * type is either LINE6_STREAM_IMPULSE or LINE6_STREAM_MONITOR
300 */
line6_pcm_acquire(struct snd_line6_pcm * line6pcm,int type,bool start)301 int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int type, bool start)
302 {
303 struct line6_pcm_stream *pstr;
304 int ret = 0, dir;
305
306 /* TODO: We should assert SNDRV_PCM_STREAM_PLAYBACK/CAPTURE == 0/1 */
307 mutex_lock(&line6pcm->state_mutex);
308 for (dir = 0; dir < 2; dir++) {
309 pstr = get_stream(line6pcm, dir);
310 ret = line6_buffer_acquire(line6pcm, pstr, dir, type);
311 if (ret < 0)
312 goto error;
313 if (!pstr->running)
314 line6_wait_clear_audio_urbs(line6pcm, pstr);
315 }
316 if (start) {
317 for (dir = 0; dir < 2; dir++) {
318 ret = line6_stream_start(line6pcm, dir, type);
319 if (ret < 0)
320 goto error;
321 }
322 }
323 error:
324 mutex_unlock(&line6pcm->state_mutex);
325 if (ret < 0)
326 line6_pcm_release(line6pcm, type);
327 return ret;
328 }
329 EXPORT_SYMBOL_GPL(line6_pcm_acquire);
330
331 /* Stop and release duplex streams */
line6_pcm_release(struct snd_line6_pcm * line6pcm,int type)332 void line6_pcm_release(struct snd_line6_pcm *line6pcm, int type)
333 {
334 struct line6_pcm_stream *pstr;
335 int dir;
336
337 mutex_lock(&line6pcm->state_mutex);
338 for (dir = 0; dir < 2; dir++)
339 line6_stream_stop(line6pcm, dir, type);
340 for (dir = 0; dir < 2; dir++) {
341 pstr = get_stream(line6pcm, dir);
342 line6_buffer_release(line6pcm, pstr, type);
343 }
344 mutex_unlock(&line6pcm->state_mutex);
345 }
346 EXPORT_SYMBOL_GPL(line6_pcm_release);
347
348 /* common PCM hw_params callback */
snd_line6_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * hw_params)349 int snd_line6_hw_params(struct snd_pcm_substream *substream,
350 struct snd_pcm_hw_params *hw_params)
351 {
352 int ret;
353 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
354 struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
355
356 mutex_lock(&line6pcm->state_mutex);
357 ret = line6_buffer_acquire(line6pcm, pstr, substream->stream,
358 LINE6_STREAM_PCM);
359 if (ret < 0)
360 goto error;
361
362 ret = snd_pcm_lib_malloc_pages(substream,
363 params_buffer_bytes(hw_params));
364 if (ret < 0) {
365 line6_buffer_release(line6pcm, pstr, LINE6_STREAM_PCM);
366 goto error;
367 }
368
369 pstr->period = params_period_bytes(hw_params);
370 error:
371 mutex_unlock(&line6pcm->state_mutex);
372 return ret;
373 }
374
375 /* common PCM hw_free callback */
snd_line6_hw_free(struct snd_pcm_substream * substream)376 int snd_line6_hw_free(struct snd_pcm_substream *substream)
377 {
378 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
379 struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
380
381 mutex_lock(&line6pcm->state_mutex);
382 line6_buffer_release(line6pcm, pstr, LINE6_STREAM_PCM);
383 mutex_unlock(&line6pcm->state_mutex);
384 return snd_pcm_lib_free_pages(substream);
385 }
386
387
388 /* control info callback */
snd_line6_control_playback_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)389 static int snd_line6_control_playback_info(struct snd_kcontrol *kcontrol,
390 struct snd_ctl_elem_info *uinfo)
391 {
392 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
393 uinfo->count = 2;
394 uinfo->value.integer.min = 0;
395 uinfo->value.integer.max = 256;
396 return 0;
397 }
398
399 /* control get callback */
snd_line6_control_playback_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)400 static int snd_line6_control_playback_get(struct snd_kcontrol *kcontrol,
401 struct snd_ctl_elem_value *ucontrol)
402 {
403 int i;
404 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
405
406 for (i = 0; i < 2; i++)
407 ucontrol->value.integer.value[i] = line6pcm->volume_playback[i];
408
409 return 0;
410 }
411
412 /* control put callback */
snd_line6_control_playback_put(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)413 static int snd_line6_control_playback_put(struct snd_kcontrol *kcontrol,
414 struct snd_ctl_elem_value *ucontrol)
415 {
416 int i, changed = 0;
417 struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
418
419 for (i = 0; i < 2; i++)
420 if (line6pcm->volume_playback[i] !=
421 ucontrol->value.integer.value[i]) {
422 line6pcm->volume_playback[i] =
423 ucontrol->value.integer.value[i];
424 changed = 1;
425 }
426
427 return changed;
428 }
429
430 /* control definition */
431 static const struct snd_kcontrol_new line6_controls[] = {
432 {
433 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
434 .name = "PCM Playback Volume",
435 .info = snd_line6_control_playback_info,
436 .get = snd_line6_control_playback_get,
437 .put = snd_line6_control_playback_put
438 },
439 {
440 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
441 .name = "Impulse Response Volume",
442 .info = snd_line6_impulse_volume_info,
443 .get = snd_line6_impulse_volume_get,
444 .put = snd_line6_impulse_volume_put
445 },
446 {
447 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
448 .name = "Impulse Response Period",
449 .info = snd_line6_impulse_period_info,
450 .get = snd_line6_impulse_period_get,
451 .put = snd_line6_impulse_period_put
452 },
453 };
454
455 /*
456 Cleanup the PCM device.
457 */
cleanup_urbs(struct line6_pcm_stream * pcms,int iso_buffers)458 static void cleanup_urbs(struct line6_pcm_stream *pcms, int iso_buffers)
459 {
460 int i;
461
462 /* Most likely impossible in current code... */
463 if (pcms->urbs == NULL)
464 return;
465
466 for (i = 0; i < iso_buffers; i++) {
467 if (pcms->urbs[i]) {
468 usb_kill_urb(pcms->urbs[i]);
469 usb_free_urb(pcms->urbs[i]);
470 }
471 }
472 kfree(pcms->urbs);
473 pcms->urbs = NULL;
474 }
475
line6_cleanup_pcm(struct snd_pcm * pcm)476 static void line6_cleanup_pcm(struct snd_pcm *pcm)
477 {
478 struct snd_line6_pcm *line6pcm = snd_pcm_chip(pcm);
479
480 cleanup_urbs(&line6pcm->out, line6pcm->line6->iso_buffers);
481 cleanup_urbs(&line6pcm->in, line6pcm->line6->iso_buffers);
482 kfree(line6pcm);
483 }
484
485 /* create a PCM device */
snd_line6_new_pcm(struct usb_line6 * line6,struct snd_pcm ** pcm_ret)486 static int snd_line6_new_pcm(struct usb_line6 *line6, struct snd_pcm **pcm_ret)
487 {
488 struct snd_pcm *pcm;
489 int err;
490
491 err = snd_pcm_new(line6->card, (char *)line6->properties->name,
492 0, 1, 1, pcm_ret);
493 if (err < 0)
494 return err;
495 pcm = *pcm_ret;
496 strcpy(pcm->name, line6->properties->name);
497
498 /* set operators */
499 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
500 &snd_line6_playback_ops);
501 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_line6_capture_ops);
502
503 /* pre-allocation of buffers */
504 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
505 snd_dma_continuous_data
506 (GFP_KERNEL), 64 * 1024,
507 128 * 1024);
508 return 0;
509 }
510
511 /*
512 Sync with PCM stream stops.
513 */
line6_pcm_disconnect(struct snd_line6_pcm * line6pcm)514 void line6_pcm_disconnect(struct snd_line6_pcm *line6pcm)
515 {
516 line6_unlink_audio_urbs(line6pcm, &line6pcm->out);
517 line6_unlink_audio_urbs(line6pcm, &line6pcm->in);
518 line6_wait_clear_audio_urbs(line6pcm, &line6pcm->out);
519 line6_wait_clear_audio_urbs(line6pcm, &line6pcm->in);
520 }
521
522 /*
523 Create and register the PCM device and mixer entries.
524 Create URBs for playback and capture.
525 */
line6_init_pcm(struct usb_line6 * line6,struct line6_pcm_properties * properties)526 int line6_init_pcm(struct usb_line6 *line6,
527 struct line6_pcm_properties *properties)
528 {
529 int i, err;
530 unsigned ep_read = line6->properties->ep_audio_r;
531 unsigned ep_write = line6->properties->ep_audio_w;
532 struct snd_pcm *pcm;
533 struct snd_line6_pcm *line6pcm;
534
535 if (!(line6->properties->capabilities & LINE6_CAP_PCM))
536 return 0; /* skip PCM initialization and report success */
537
538 err = snd_line6_new_pcm(line6, &pcm);
539 if (err < 0)
540 return err;
541
542 line6pcm = kzalloc(sizeof(*line6pcm), GFP_KERNEL);
543 if (!line6pcm)
544 return -ENOMEM;
545
546 mutex_init(&line6pcm->state_mutex);
547 line6pcm->pcm = pcm;
548 line6pcm->properties = properties;
549 line6pcm->volume_playback[0] = line6pcm->volume_playback[1] = 255;
550 line6pcm->volume_monitor = 255;
551 line6pcm->line6 = line6;
552
553 spin_lock_init(&line6pcm->out.lock);
554 spin_lock_init(&line6pcm->in.lock);
555 line6pcm->impulse_period = LINE6_IMPULSE_DEFAULT_PERIOD;
556
557 line6->line6pcm = line6pcm;
558
559 pcm->private_data = line6pcm;
560 pcm->private_free = line6_cleanup_pcm;
561
562 line6pcm->max_packet_size_in =
563 usb_maxpacket(line6->usbdev,
564 usb_rcvisocpipe(line6->usbdev, ep_read), 0);
565 line6pcm->max_packet_size_out =
566 usb_maxpacket(line6->usbdev,
567 usb_sndisocpipe(line6->usbdev, ep_write), 1);
568 if (!line6pcm->max_packet_size_in || !line6pcm->max_packet_size_out) {
569 dev_err(line6pcm->line6->ifcdev,
570 "cannot get proper max packet size\n");
571 return -EINVAL;
572 }
573
574 err = line6_create_audio_out_urbs(line6pcm);
575 if (err < 0)
576 return err;
577
578 err = line6_create_audio_in_urbs(line6pcm);
579 if (err < 0)
580 return err;
581
582 /* mixer: */
583 for (i = 0; i < ARRAY_SIZE(line6_controls); i++) {
584 err = snd_ctl_add(line6->card,
585 snd_ctl_new1(&line6_controls[i], line6pcm));
586 if (err < 0)
587 return err;
588 }
589
590 return 0;
591 }
592 EXPORT_SYMBOL_GPL(line6_init_pcm);
593
594 /* prepare pcm callback */
snd_line6_prepare(struct snd_pcm_substream * substream)595 int snd_line6_prepare(struct snd_pcm_substream *substream)
596 {
597 struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
598 struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
599
600 mutex_lock(&line6pcm->state_mutex);
601 if (!pstr->running)
602 line6_wait_clear_audio_urbs(line6pcm, pstr);
603
604 if (!test_and_set_bit(LINE6_FLAG_PREPARED, &line6pcm->flags)) {
605 line6pcm->out.count = 0;
606 line6pcm->out.pos = 0;
607 line6pcm->out.pos_done = 0;
608 line6pcm->out.bytes = 0;
609 line6pcm->in.count = 0;
610 line6pcm->in.pos_done = 0;
611 line6pcm->in.bytes = 0;
612 }
613
614 mutex_unlock(&line6pcm->state_mutex);
615 return 0;
616 }
617
