summaryrefslogtreecommitdiffstats
path: root/sound/drivers/dummy.c
blob: a61640cf7ae7c3b565d79c328a24aaebd972702a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
/*
 *  Dummy soundcard
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/wait.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/rawmidi.h>
#include <sound/initval.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");

#define MAX_PCM_DEVICES		4
#define MAX_PCM_SUBSTREAMS	16
#define MAX_MIDI_DEVICES	2

#if 0 /* emu10k1 emulation */
#define MAX_BUFFER_SIZE		(128 * 1024)
static int emu10k1_playback_constraints(snd_pcm_runtime_t *runtime)
{
	int err;
	if ((err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
		return err;
	if ((err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX)) < 0)
		return err;
	return 0;
}
#define add_playback_constraints emu10k1_playback_constraints
#endif

#if 0 /* RME9652 emulation */
#define MAX_BUFFER_SIZE		(26 * 64 * 1024)
#define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
#define USE_CHANNELS_MIN	26
#define USE_CHANNELS_MAX	26
#define USE_PERIODS_MIN		2
#define USE_PERIODS_MAX		2
#endif

#if 0 /* ICE1712 emulation */
#define MAX_BUFFER_SIZE		(256 * 1024)
#define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
#define USE_CHANNELS_MIN	10
#define USE_CHANNELS_MAX	10
#define USE_PERIODS_MIN		1
#define USE_PERIODS_MAX		1024
#endif

#if 0 /* UDA1341 emulation */
#define MAX_BUFFER_SIZE		(16380)
#define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
#define USE_CHANNELS_MIN	2
#define USE_CHANNELS_MAX	2
#define USE_PERIODS_MIN		2
#define USE_PERIODS_MAX		255
#endif

#if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
#define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
#define USE_CHANNELS_MIN	2
#define USE_CHANNELS_MAX	2
#define USE_RATE		SNDRV_PCM_RATE_48000
#define USE_RATE_MIN		48000
#define USE_RATE_MAX		48000
#endif


/* defaults */
#ifndef MAX_BUFFER_SIZE
#define MAX_BUFFER_SIZE		(64*1024)
#endif
#ifndef USE_FORMATS
#define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
#endif
#ifndef USE_RATE
#define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
#define USE_RATE_MIN		5500
#define USE_RATE_MAX		48000
#endif
#ifndef USE_CHANNELS_MIN
#define USE_CHANNELS_MIN 	1
#endif
#ifndef USE_CHANNELS_MAX
#define USE_CHANNELS_MAX 	2
#endif
#ifndef USE_PERIODS_MIN
#define USE_PERIODS_MIN 	1
#endif
#ifndef USE_PERIODS_MAX
#define USE_PERIODS_MAX 	1024
#endif
#ifndef add_playback_constraints
#define add_playback_constraints(x) 0
#endif
#ifndef add_capture_constraints
#define add_capture_constraints(x) 0
#endif

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
module_param_array(pcm_devs, int, NULL, 0444);
MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
module_param_array(pcm_substreams, int, NULL, 0444);
MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
//module_param_array(midi_devs, int, NULL, 0444);
//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");

#define MIXER_ADDR_MASTER	0
#define MIXER_ADDR_LINE		1
#define MIXER_ADDR_MIC		2
#define MIXER_ADDR_SYNTH	3
#define MIXER_ADDR_CD		4
#define MIXER_ADDR_LAST		4

typedef struct snd_card_dummy {
	snd_card_t *card;
	spinlock_t mixer_lock;
	int mixer_volume[MIXER_ADDR_LAST+1][2];
	int capture_source[MIXER_ADDR_LAST+1][2];
} snd_card_dummy_t;

typedef struct snd_card_dummy_pcm {
	snd_card_dummy_t *dummy;
	spinlock_t lock;
	struct timer_list timer;
	unsigned int pcm_size;
	unsigned int pcm_count;
	unsigned int pcm_bps;		/* bytes per second */
	unsigned int pcm_jiffie;	/* bytes per one jiffie */
	unsigned int pcm_irq_pos;	/* IRQ position */
	unsigned int pcm_buf_pos;	/* position in buffer */
	snd_pcm_substream_t *substream;
} snd_card_dummy_pcm_t;

static snd_card_t *snd_dummy_cards[SNDRV_CARDS] = SNDRV_DEFAULT_PTR;


static void snd_card_dummy_pcm_timer_start(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;

	dpcm->timer.expires = 1 + jiffies;
	add_timer(&dpcm->timer);
}

static void snd_card_dummy_pcm_timer_stop(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;

	del_timer(&dpcm->timer);
}

static int snd_card_dummy_playback_trigger(snd_pcm_substream_t * substream,
					   int cmd)
{
	if (cmd == SNDRV_PCM_TRIGGER_START) {
		snd_card_dummy_pcm_timer_start(substream);
	} else if (cmd == SNDRV_PCM_TRIGGER_STOP) {
		snd_card_dummy_pcm_timer_stop(substream);
	} else {
		return -EINVAL;
	}
	return 0;
}

static int snd_card_dummy_capture_trigger(snd_pcm_substream_t * substream,
					  int cmd)
{
	if (cmd == SNDRV_PCM_TRIGGER_START) {
		snd_card_dummy_pcm_timer_start(substream);
	} else if (cmd == SNDRV_PCM_TRIGGER_STOP) {
		snd_card_dummy_pcm_timer_stop(substream);
	} else {
		return -EINVAL;
	}
	return 0;
}

static int snd_card_dummy_pcm_prepare(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;
	unsigned int bps;

	bps = runtime->rate * runtime->channels;
	bps *= snd_pcm_format_width(runtime->format);
	bps /= 8;
	if (bps <= 0)
		return -EINVAL;
	dpcm->pcm_bps = bps;
	dpcm->pcm_jiffie = bps / HZ;
	dpcm->pcm_size = snd_pcm_lib_buffer_bytes(substream);
	dpcm->pcm_count = snd_pcm_lib_period_bytes(substream);
	dpcm->pcm_irq_pos = 0;
	dpcm->pcm_buf_pos = 0;
	return 0;
}

static int snd_card_dummy_playback_prepare(snd_pcm_substream_t * substream)
{
	return snd_card_dummy_pcm_prepare(substream);
}

static int snd_card_dummy_capture_prepare(snd_pcm_substream_t * substream)
{
	return snd_card_dummy_pcm_prepare(substream);
}

static void snd_card_dummy_pcm_timer_function(unsigned long data)
{
	snd_card_dummy_pcm_t *dpcm = (snd_card_dummy_pcm_t *)data;
	
	dpcm->timer.expires = 1 + jiffies;
	add_timer(&dpcm->timer);
	spin_lock_irq(&dpcm->lock);
	dpcm->pcm_irq_pos += dpcm->pcm_jiffie;
	dpcm->pcm_buf_pos += dpcm->pcm_jiffie;
	dpcm->pcm_buf_pos %= dpcm->pcm_size;
	if (dpcm->pcm_irq_pos >= dpcm->pcm_count) {
		dpcm->pcm_irq_pos %= dpcm->pcm_count;
		snd_pcm_period_elapsed(dpcm->substream);
	}
	spin_unlock_irq(&dpcm->lock);	
}

static snd_pcm_uframes_t snd_card_dummy_playback_pointer(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;

	return bytes_to_frames(runtime, dpcm->pcm_buf_pos);
}

static snd_pcm_uframes_t snd_card_dummy_capture_pointer(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;

	return bytes_to_frames(runtime, dpcm->pcm_buf_pos);
}

static snd_pcm_hardware_t snd_card_dummy_playback =
{
	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_MMAP_VALID),
	.formats =		USE_FORMATS,
	.rates =		USE_RATE,
	.rate_min =		USE_RATE_MIN,
	.rate_max =		USE_RATE_MAX,
	.channels_min =		USE_CHANNELS_MIN,
	.channels_max =		USE_CHANNELS_MAX,
	.buffer_bytes_max =	MAX_BUFFER_SIZE,
	.period_bytes_min =	64,
	.period_bytes_max =	MAX_BUFFER_SIZE,
	.periods_min =		USE_PERIODS_MIN,
	.periods_max =		USE_PERIODS_MAX,
	.fifo_size =		0,
};

static snd_pcm_hardware_t snd_card_dummy_capture =
{
	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_MMAP_VALID),
	.formats =		USE_FORMATS,
	.rates =		USE_RATE,
	.rate_min =		USE_RATE_MIN,
	.rate_max =		USE_RATE_MAX,
	.channels_min =		USE_CHANNELS_MIN,
	.channels_max =		USE_CHANNELS_MAX,
	.buffer_bytes_max =	MAX_BUFFER_SIZE,
	.period_bytes_min =	64,
	.period_bytes_max =	MAX_BUFFER_SIZE,
	.periods_min =		USE_PERIODS_MIN,
	.periods_max =		USE_PERIODS_MAX,
	.fifo_size =		0,
};

static void snd_card_dummy_runtime_free(snd_pcm_runtime_t *runtime)
{
	snd_card_dummy_pcm_t *dpcm = runtime->private_data;
	kfree(dpcm);
}

static int snd_card_dummy_hw_params(snd_pcm_substream_t * substream,
				    snd_pcm_hw_params_t * hw_params)
{
	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
}

static int snd_card_dummy_hw_free(snd_pcm_substream_t * substream)
{
	return snd_pcm_lib_free_pages(substream);
}

static int snd_card_dummy_playback_open(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm;
	int err;

	dpcm = kcalloc(1, sizeof(*dpcm), GFP_KERNEL);
	if (dpcm == NULL)
		return -ENOMEM;
	init_timer(&dpcm->timer);
	dpcm->timer.data = (unsigned long) dpcm;
	dpcm->timer.function = snd_card_dummy_pcm_timer_function;
	spin_lock_init(&dpcm->lock);
	dpcm->substream = substream;
	runtime->private_data = dpcm;
	runtime->private_free = snd_card_dummy_runtime_free;
	runtime->hw = snd_card_dummy_playback;
	if (substream->pcm->device & 1) {
		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
	}
	if (substream->pcm->device & 2)
		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
	if ((err = add_playback_constraints(runtime)) < 0) {
		kfree(dpcm);
		return err;
	}

	return 0;
}

static int snd_card_dummy_capture_open(snd_pcm_substream_t * substream)
{
	snd_pcm_runtime_t *runtime = substream->runtime;
	snd_card_dummy_pcm_t *dpcm;
	int err;

	dpcm = kcalloc(1, sizeof(*dpcm), GFP_KERNEL);
	if (dpcm == NULL)
		return -ENOMEM;
	init_timer(&dpcm->timer);
	dpcm->timer.data = (unsigned long) dpcm;
	dpcm->timer.function = snd_card_dummy_pcm_timer_function;
	spin_lock_init(&dpcm->lock);
	dpcm->substream = substream;
	runtime->private_data = dpcm;
	runtime->private_free = snd_card_dummy_runtime_free;
	runtime->hw = snd_card_dummy_capture;
	if (substream->pcm->device == 1) {
		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
	}
	if (substream->pcm->device & 2)
		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
	if ((err = add_capture_constraints(runtime)) < 0) {
		kfree(dpcm);
		return err;
	}

	return 0;
}

static int snd_card_dummy_playback_close(snd_pcm_substream_t * substream)
{
	return 0;
}

static int snd_card_dummy_capture_close(snd_pcm_substream_t * substream)
{
	return 0;
}

static snd_pcm_ops_t snd_card_dummy_playback_ops = {
	.open =			snd_card_dummy_playback_open,
	.close =		snd_card_dummy_playback_close,
	.ioctl =		snd_pcm_lib_ioctl,
	.hw_params =		snd_card_dummy_hw_params,
	.hw_free =		snd_card_dummy_hw_free,
	.prepare =		snd_card_dummy_playback_prepare,
	.trigger =		snd_card_dummy_playback_trigger,
	.pointer =		snd_card_dummy_playback_pointer,
};

static snd_pcm_ops_t snd_card_dummy_capture_ops = {
	.open =			snd_card_dummy_capture_open,
	.close =		snd_card_dummy_capture_close,
	.ioctl =		snd_pcm_lib_ioctl,
	.hw_params =		snd_card_dummy_hw_params,
	.hw_free =		snd_card_dummy_hw_free,
	.prepare =		snd_card_dummy_capture_prepare,
	.trigger =		snd_card_dummy_capture_trigger,
	.pointer =		snd_card_dummy_capture_pointer,
};

static int __init snd_card_dummy_pcm(snd_card_dummy_t *dummy, int device, int substreams)
{
	snd_pcm_t *pcm;
	int err;

	if ((err = snd_pcm_new(dummy->card, "Dummy PCM", device, substreams, substreams, &pcm)) < 0)
		return err;
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_card_dummy_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_dummy_capture_ops);
	pcm->private_data = dummy;
	pcm->info_flags = 0;
	strcpy(pcm->name, "Dummy PCM");
	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
					      snd_dma_continuous_data(GFP_KERNEL),
					      0, 64*1024);
	return 0;
}

#define DUMMY_VOLUME(xname, xindex, addr) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_dummy_volume_info, \
  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
  .private_value = addr }

static int snd_dummy_volume_info(snd_kcontrol_t * kcontrol, snd_ctl_elem_info_t * uinfo)
{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = 2;
	uinfo->value.integer.min = -50;
	uinfo->value.integer.max = 100;
	return 0;
}
 
static int snd_dummy_volume_get(snd_kcontrol_t * kcontrol, snd_ctl_elem_value_t * ucontrol)
{
	snd_card_dummy_t *dummy = snd_kcontrol_chip(kcontrol);
	unsigned long flags;
	int addr = kcontrol->private_value;

	spin_lock_irqsave(&dummy->mixer_lock, flags);
	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
	spin_unlock_irqrestore(&dummy->mixer_lock, flags);
	return 0;
}

static int snd_dummy_volume_put(snd_kcontrol_t * kcontrol, snd_ctl_elem_value_t * ucontrol)
{
	snd_card_dummy_t *dummy = snd_kcontrol_chip(kcontrol);
	unsigned long flags;
	int change, addr = kcontrol->private_value;
	int left, right;

	left = ucontrol->value.integer.value[0];
	if (left < -50)
		left = -50;
	if (left > 100)
		left = 100;
	right = ucontrol->value.integer.value[1];
	if (right < -50)
		right = -50;
	if (right > 100)
		right = 100;
	spin_lock_irqsave(&dummy->mixer_lock, flags);
	change = dummy->mixer_volume[addr][0] != left ||
	         dummy->mixer_volume[addr][1] != right;
	dummy->mixer_volume[addr][0] = left;
	dummy->mixer_volume[addr][1] = right;
	spin_unlock_irqrestore(&dummy->mixer_lock, flags);
	return change;
}

#define DUMMY_CAPSRC(xname, xindex, addr) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_dummy_capsrc_info, \
  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
  .private_value = addr }

static int snd_dummy_capsrc_info(snd_kcontrol_t * kcontrol, snd_ctl_elem_info_t * uinfo)
{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
	uinfo->count = 2;
	uinfo->value.integer.min = 0;
	uinfo->value.integer.max = 1;
	return 0;
}
 
static int snd_dummy_capsrc_get(snd_kcontrol_t * kcontrol, snd_ctl_elem_value_t * ucontrol)
{
	snd_card_dummy_t *dummy = snd_kcontrol_chip(kcontrol);
	unsigned long flags;
	int addr = kcontrol->private_value;

	spin_lock_irqsave(&dummy->mixer_lock, flags);
	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
	spin_unlock_irqrestore(&dummy->mixer_lock, flags);
	return 0;
}

static int snd_dummy_capsrc_put(snd_kcontrol_t * kcontrol, snd_ctl_elem_value_t * ucontrol)
{
	snd_card_dummy_t *dummy = snd_kcontrol_chip(kcontrol);
	unsigned long flags;
	int change, addr = kcontrol->private_value;
	int left, right;

	left = ucontrol->value.integer.value[0] & 1;
	right = ucontrol->value.integer.value[1] & 1;
	spin_lock_irqsave(&dummy->mixer_lock, flags);
	change = dummy->capture_source[addr][0] != left &&
	         dummy->capture_source[addr][1] != right;
	dummy->capture_source[addr][0] = left;
	dummy->capture_source[addr][1] = right;
	spin_unlock_irqrestore(&dummy->mixer_lock, flags);
	return change;
}

static snd_kcontrol_new_t snd_dummy_controls[] = {
DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_MASTER),
DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_MASTER),
DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MASTER),
DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_MASTER)
};

static int __init snd_card_dummy_new_mixer(snd_card_dummy_t * dummy)
{
	snd_card_t *card = dummy->card;
	unsigned int idx;
	int err;

	snd_assert(dummy != NULL, return -EINVAL);
	spin_lock_init(&dummy->mixer_lock);
	strcpy(card->mixername, "Dummy Mixer");

	for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
		if ((err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy))) < 0)
			return err;
	}
	return 0;
}

static int __init snd_card_dummy_probe(int dev)
{
	snd_card_t *card;
	struct snd_card_dummy *dummy;
	int idx, err;

	if (!enable[dev])
		return -ENODEV;
	card = snd_card_new(index[dev], id[dev], THIS_MODULE,
			    sizeof(struct snd_card_dummy));
	if (card == NULL)
		return -ENOMEM;
	dummy = (struct snd_card_dummy *)card->private_data;
	dummy->card = card;
	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
		if (pcm_substreams[dev] < 1)
			pcm_substreams[dev] = 1;
		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
		if ((err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev])) < 0)
			goto __nodev;
	}
	if ((err = snd_card_dummy_new_mixer(dummy)) < 0)
		goto __nodev;
	strcpy(card->driver, "Dummy");
	strcpy(card->shortname, "Dummy");
	sprintf(card->longname, "Dummy %i", dev + 1);
	if ((err = snd_card_register(card)) == 0) {
		snd_dummy_cards[dev] = card;
		return 0;
	}
      __nodev:
	snd_card_free(card);
	return err;
}

static int __init alsa_card_dummy_init(void)
{
	int dev, cards;

	for (dev = cards = 0; dev < SNDRV_CARDS && enable[dev]; dev++) {
		if (snd_card_dummy_probe(dev) < 0) {
#ifdef MODULE
			printk(KERN_ERR "Dummy soundcard #%i not found or device busy\n", dev + 1);
#endif
			break;
		}
		cards++;
	}
	if (!cards) {
#ifdef MODULE
		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
#endif
		return -ENODEV;
	}
	return 0;
}

static void __exit alsa_card_dummy_exit(void)
{
	int idx;

	for (idx = 0; idx < SNDRV_CARDS; idx++)
		snd_card_free(snd_dummy_cards[idx]);
}

module_init(alsa_card_dummy_init)
module_exit(alsa_card_dummy_exit)