xref: /openbmc/linux/sound/drivers/dummy.c (revision e868d61272caa648214046a096e5a6bfc068dc8c)
1 /*
2  *  Dummy soundcard
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
4  *
5  *   This program is free software; you can redistribute it and/or modify
6  *   it under the terms of the GNU General Public License as published by
7  *   the Free Software Foundation; either version 2 of the License, or
8  *   (at your option) any later version.
9  *
10  *   This program is distributed in the hope that it will be useful,
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *   GNU General Public License for more details.
14  *
15  *   You should have received a copy of the GNU General Public License
16  *   along with this program; if not, write to the Free Software
17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
18  *
19  */
20 
21 #include <sound/driver.h>
22 #include <linux/init.h>
23 #include <linux/err.h>
24 #include <linux/platform_device.h>
25 #include <linux/jiffies.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/wait.h>
29 #include <linux/moduleparam.h>
30 #include <sound/core.h>
31 #include <sound/control.h>
32 #include <sound/tlv.h>
33 #include <sound/pcm.h>
34 #include <sound/rawmidi.h>
35 #include <sound/initval.h>
36 
37 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
38 MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
39 MODULE_LICENSE("GPL");
40 MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
41 
42 #define MAX_PCM_DEVICES		4
43 #define MAX_PCM_SUBSTREAMS	16
44 #define MAX_MIDI_DEVICES	2
45 
46 #if 0 /* emu10k1 emulation */
47 #define MAX_BUFFER_SIZE		(128 * 1024)
48 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
49 {
50 	int err;
51 	if ((err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
52 		return err;
53 	if ((err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX)) < 0)
54 		return err;
55 	return 0;
56 }
57 #define add_playback_constraints emu10k1_playback_constraints
58 #endif
59 
60 #if 0 /* RME9652 emulation */
61 #define MAX_BUFFER_SIZE		(26 * 64 * 1024)
62 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
63 #define USE_CHANNELS_MIN	26
64 #define USE_CHANNELS_MAX	26
65 #define USE_PERIODS_MIN		2
66 #define USE_PERIODS_MAX		2
67 #endif
68 
69 #if 0 /* ICE1712 emulation */
70 #define MAX_BUFFER_SIZE		(256 * 1024)
71 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
72 #define USE_CHANNELS_MIN	10
73 #define USE_CHANNELS_MAX	10
74 #define USE_PERIODS_MIN		1
75 #define USE_PERIODS_MAX		1024
76 #endif
77 
78 #if 0 /* UDA1341 emulation */
79 #define MAX_BUFFER_SIZE		(16380)
80 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
81 #define USE_CHANNELS_MIN	2
82 #define USE_CHANNELS_MAX	2
83 #define USE_PERIODS_MIN		2
84 #define USE_PERIODS_MAX		255
85 #endif
86 
87 #if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
88 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
89 #define USE_CHANNELS_MIN	2
90 #define USE_CHANNELS_MAX	2
91 #define USE_RATE		SNDRV_PCM_RATE_48000
92 #define USE_RATE_MIN		48000
93 #define USE_RATE_MAX		48000
94 #endif
95 
96 #if 0 /* CA0106 */
97 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
98 #define USE_CHANNELS_MIN	2
99 #define USE_CHANNELS_MAX	2
100 #define USE_RATE		(SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000)
101 #define USE_RATE_MIN		48000
102 #define USE_RATE_MAX		192000
103 #define MAX_BUFFER_SIZE		((65536-64)*8)
104 #define MAX_PERIOD_SIZE		(65536-64)
105 #define USE_PERIODS_MIN		2
106 #define USE_PERIODS_MAX		8
107 #endif
108 
109 
110 /* defaults */
111 #ifndef MAX_BUFFER_SIZE
112 #define MAX_BUFFER_SIZE		(64*1024)
113 #endif
114 #ifndef MAX_PERIOD_SIZE
115 #define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
116 #endif
117 #ifndef USE_FORMATS
118 #define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
119 #endif
120 #ifndef USE_RATE
121 #define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
122 #define USE_RATE_MIN		5500
123 #define USE_RATE_MAX		48000
124 #endif
125 #ifndef USE_CHANNELS_MIN
126 #define USE_CHANNELS_MIN 	1
127 #endif
128 #ifndef USE_CHANNELS_MAX
129 #define USE_CHANNELS_MAX 	2
130 #endif
131 #ifndef USE_PERIODS_MIN
132 #define USE_PERIODS_MIN 	1
133 #endif
134 #ifndef USE_PERIODS_MAX
135 #define USE_PERIODS_MAX 	1024
136 #endif
137 #ifndef add_playback_constraints
138 #define add_playback_constraints(x) 0
139 #endif
140 #ifndef add_capture_constraints
141 #define add_capture_constraints(x) 0
142 #endif
143 
144 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
145 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
146 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
147 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
148 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
149 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
150 
151 module_param_array(index, int, NULL, 0444);
152 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
153 module_param_array(id, charp, NULL, 0444);
154 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
155 module_param_array(enable, bool, NULL, 0444);
156 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
157 module_param_array(pcm_devs, int, NULL, 0444);
158 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
159 module_param_array(pcm_substreams, int, NULL, 0444);
160 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
161 //module_param_array(midi_devs, int, NULL, 0444);
162 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
163 
164 static struct platform_device *devices[SNDRV_CARDS];
165 
166 #define MIXER_ADDR_MASTER	0
167 #define MIXER_ADDR_LINE		1
168 #define MIXER_ADDR_MIC		2
169 #define MIXER_ADDR_SYNTH	3
170 #define MIXER_ADDR_CD		4
171 #define MIXER_ADDR_LAST		4
172 
173 struct snd_dummy {
174 	struct snd_card *card;
175 	struct snd_pcm *pcm;
176 	spinlock_t mixer_lock;
177 	int mixer_volume[MIXER_ADDR_LAST+1][2];
178 	int capture_source[MIXER_ADDR_LAST+1][2];
179 };
180 
181 struct snd_dummy_pcm {
182 	struct snd_dummy *dummy;
183 	spinlock_t lock;
184 	struct timer_list timer;
185 	unsigned int pcm_size;
186 	unsigned int pcm_count;
187 	unsigned int pcm_bps;		/* bytes per second */
188 	unsigned int pcm_jiffie;	/* bytes per one jiffie */
189 	unsigned int pcm_irq_pos;	/* IRQ position */
190 	unsigned int pcm_buf_pos;	/* position in buffer */
191 	struct snd_pcm_substream *substream;
192 };
193 
194 
195 static inline void snd_card_dummy_pcm_timer_start(struct snd_dummy_pcm *dpcm)
196 {
197 	dpcm->timer.expires = 1 + jiffies;
198 	add_timer(&dpcm->timer);
199 }
200 
201 static inline void snd_card_dummy_pcm_timer_stop(struct snd_dummy_pcm *dpcm)
202 {
203 	del_timer(&dpcm->timer);
204 }
205 
206 static int snd_card_dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
207 {
208 	struct snd_pcm_runtime *runtime = substream->runtime;
209 	struct snd_dummy_pcm *dpcm = runtime->private_data;
210 	int err = 0;
211 
212 	spin_lock(&dpcm->lock);
213 	switch (cmd) {
214 	case SNDRV_PCM_TRIGGER_START:
215 	case SNDRV_PCM_TRIGGER_RESUME:
216 		snd_card_dummy_pcm_timer_start(dpcm);
217 		break;
218 	case SNDRV_PCM_TRIGGER_STOP:
219 	case SNDRV_PCM_TRIGGER_SUSPEND:
220 		snd_card_dummy_pcm_timer_stop(dpcm);
221 		break;
222 	default:
223 		err = -EINVAL;
224 		break;
225 	}
226 	spin_unlock(&dpcm->lock);
227 	return 0;
228 }
229 
230 static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream)
231 {
232 	struct snd_pcm_runtime *runtime = substream->runtime;
233 	struct snd_dummy_pcm *dpcm = runtime->private_data;
234 	unsigned int bps;
235 
236 	bps = runtime->rate * runtime->channels;
237 	bps *= snd_pcm_format_width(runtime->format);
238 	bps /= 8;
239 	if (bps <= 0)
240 		return -EINVAL;
241 	dpcm->pcm_bps = bps;
242 	dpcm->pcm_jiffie = bps / HZ;
243 	dpcm->pcm_size = snd_pcm_lib_buffer_bytes(substream);
244 	dpcm->pcm_count = snd_pcm_lib_period_bytes(substream);
245 	dpcm->pcm_irq_pos = 0;
246 	dpcm->pcm_buf_pos = 0;
247 	return 0;
248 }
249 
250 static void snd_card_dummy_pcm_timer_function(unsigned long data)
251 {
252 	struct snd_dummy_pcm *dpcm = (struct snd_dummy_pcm *)data;
253 	unsigned long flags;
254 
255 	spin_lock_irqsave(&dpcm->lock, flags);
256 	dpcm->timer.expires = 1 + jiffies;
257 	add_timer(&dpcm->timer);
258 	dpcm->pcm_irq_pos += dpcm->pcm_jiffie;
259 	dpcm->pcm_buf_pos += dpcm->pcm_jiffie;
260 	dpcm->pcm_buf_pos %= dpcm->pcm_size;
261 	if (dpcm->pcm_irq_pos >= dpcm->pcm_count) {
262 		dpcm->pcm_irq_pos %= dpcm->pcm_count;
263 		spin_unlock_irqrestore(&dpcm->lock, flags);
264 		snd_pcm_period_elapsed(dpcm->substream);
265 	} else
266 		spin_unlock_irqrestore(&dpcm->lock, flags);
267 }
268 
269 static snd_pcm_uframes_t snd_card_dummy_pcm_pointer(struct snd_pcm_substream *substream)
270 {
271 	struct snd_pcm_runtime *runtime = substream->runtime;
272 	struct snd_dummy_pcm *dpcm = runtime->private_data;
273 
274 	return bytes_to_frames(runtime, dpcm->pcm_buf_pos);
275 }
276 
277 static struct snd_pcm_hardware snd_card_dummy_playback =
278 {
279 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
280 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
281 	.formats =		USE_FORMATS,
282 	.rates =		USE_RATE,
283 	.rate_min =		USE_RATE_MIN,
284 	.rate_max =		USE_RATE_MAX,
285 	.channels_min =		USE_CHANNELS_MIN,
286 	.channels_max =		USE_CHANNELS_MAX,
287 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
288 	.period_bytes_min =	64,
289 	.period_bytes_max =	MAX_PERIOD_SIZE,
290 	.periods_min =		USE_PERIODS_MIN,
291 	.periods_max =		USE_PERIODS_MAX,
292 	.fifo_size =		0,
293 };
294 
295 static struct snd_pcm_hardware snd_card_dummy_capture =
296 {
297 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
298 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
299 	.formats =		USE_FORMATS,
300 	.rates =		USE_RATE,
301 	.rate_min =		USE_RATE_MIN,
302 	.rate_max =		USE_RATE_MAX,
303 	.channels_min =		USE_CHANNELS_MIN,
304 	.channels_max =		USE_CHANNELS_MAX,
305 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
306 	.period_bytes_min =	64,
307 	.period_bytes_max =	MAX_PERIOD_SIZE,
308 	.periods_min =		USE_PERIODS_MIN,
309 	.periods_max =		USE_PERIODS_MAX,
310 	.fifo_size =		0,
311 };
312 
313 static void snd_card_dummy_runtime_free(struct snd_pcm_runtime *runtime)
314 {
315 	kfree(runtime->private_data);
316 }
317 
318 static int snd_card_dummy_hw_params(struct snd_pcm_substream *substream,
319 				    struct snd_pcm_hw_params *hw_params)
320 {
321 	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
322 }
323 
324 static int snd_card_dummy_hw_free(struct snd_pcm_substream *substream)
325 {
326 	return snd_pcm_lib_free_pages(substream);
327 }
328 
329 static struct snd_dummy_pcm *new_pcm_stream(struct snd_pcm_substream *substream)
330 {
331 	struct snd_dummy_pcm *dpcm;
332 
333 	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
334 	if (! dpcm)
335 		return dpcm;
336 	init_timer(&dpcm->timer);
337 	dpcm->timer.data = (unsigned long) dpcm;
338 	dpcm->timer.function = snd_card_dummy_pcm_timer_function;
339 	spin_lock_init(&dpcm->lock);
340 	dpcm->substream = substream;
341 	return dpcm;
342 }
343 
344 static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream)
345 {
346 	struct snd_pcm_runtime *runtime = substream->runtime;
347 	struct snd_dummy_pcm *dpcm;
348 	int err;
349 
350 	if ((dpcm = new_pcm_stream(substream)) == NULL)
351 		return -ENOMEM;
352 	runtime->private_data = dpcm;
353 	runtime->private_free = snd_card_dummy_runtime_free;
354 	runtime->hw = snd_card_dummy_playback;
355 	if (substream->pcm->device & 1) {
356 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
357 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
358 	}
359 	if (substream->pcm->device & 2)
360 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
361 	if ((err = add_playback_constraints(runtime)) < 0) {
362 		kfree(dpcm);
363 		return err;
364 	}
365 
366 	return 0;
367 }
368 
369 static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream)
370 {
371 	struct snd_pcm_runtime *runtime = substream->runtime;
372 	struct snd_dummy_pcm *dpcm;
373 	int err;
374 
375 	if ((dpcm = new_pcm_stream(substream)) == NULL)
376 		return -ENOMEM;
377 	runtime->private_data = dpcm;
378 	runtime->private_free = snd_card_dummy_runtime_free;
379 	runtime->hw = snd_card_dummy_capture;
380 	if (substream->pcm->device == 1) {
381 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
382 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
383 	}
384 	if (substream->pcm->device & 2)
385 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
386 	if ((err = add_capture_constraints(runtime)) < 0) {
387 		kfree(dpcm);
388 		return err;
389 	}
390 
391 	return 0;
392 }
393 
394 static int snd_card_dummy_playback_close(struct snd_pcm_substream *substream)
395 {
396 	return 0;
397 }
398 
399 static int snd_card_dummy_capture_close(struct snd_pcm_substream *substream)
400 {
401 	return 0;
402 }
403 
404 static struct snd_pcm_ops snd_card_dummy_playback_ops = {
405 	.open =			snd_card_dummy_playback_open,
406 	.close =		snd_card_dummy_playback_close,
407 	.ioctl =		snd_pcm_lib_ioctl,
408 	.hw_params =		snd_card_dummy_hw_params,
409 	.hw_free =		snd_card_dummy_hw_free,
410 	.prepare =		snd_card_dummy_pcm_prepare,
411 	.trigger =		snd_card_dummy_pcm_trigger,
412 	.pointer =		snd_card_dummy_pcm_pointer,
413 };
414 
415 static struct snd_pcm_ops snd_card_dummy_capture_ops = {
416 	.open =			snd_card_dummy_capture_open,
417 	.close =		snd_card_dummy_capture_close,
418 	.ioctl =		snd_pcm_lib_ioctl,
419 	.hw_params =		snd_card_dummy_hw_params,
420 	.hw_free =		snd_card_dummy_hw_free,
421 	.prepare =		snd_card_dummy_pcm_prepare,
422 	.trigger =		snd_card_dummy_pcm_trigger,
423 	.pointer =		snd_card_dummy_pcm_pointer,
424 };
425 
426 static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
427 					int substreams)
428 {
429 	struct snd_pcm *pcm;
430 	int err;
431 
432 	if ((err = snd_pcm_new(dummy->card, "Dummy PCM", device,
433 			       substreams, substreams, &pcm)) < 0)
434 		return err;
435 	dummy->pcm = pcm;
436 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_card_dummy_playback_ops);
437 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_dummy_capture_ops);
438 	pcm->private_data = dummy;
439 	pcm->info_flags = 0;
440 	strcpy(pcm->name, "Dummy PCM");
441 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
442 					      snd_dma_continuous_data(GFP_KERNEL),
443 					      0, 64*1024);
444 	return 0;
445 }
446 
447 #define DUMMY_VOLUME(xname, xindex, addr) \
448 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
449   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
450   .name = xname, .index = xindex, \
451   .info = snd_dummy_volume_info, \
452   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
453   .private_value = addr, \
454   .tlv = { .p = db_scale_dummy } }
455 
456 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
457 				 struct snd_ctl_elem_info *uinfo)
458 {
459 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
460 	uinfo->count = 2;
461 	uinfo->value.integer.min = -50;
462 	uinfo->value.integer.max = 100;
463 	return 0;
464 }
465 
466 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
467 				struct snd_ctl_elem_value *ucontrol)
468 {
469 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
470 	int addr = kcontrol->private_value;
471 
472 	spin_lock_irq(&dummy->mixer_lock);
473 	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
474 	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
475 	spin_unlock_irq(&dummy->mixer_lock);
476 	return 0;
477 }
478 
479 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
480 				struct snd_ctl_elem_value *ucontrol)
481 {
482 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
483 	int change, addr = kcontrol->private_value;
484 	int left, right;
485 
486 	left = ucontrol->value.integer.value[0];
487 	if (left < -50)
488 		left = -50;
489 	if (left > 100)
490 		left = 100;
491 	right = ucontrol->value.integer.value[1];
492 	if (right < -50)
493 		right = -50;
494 	if (right > 100)
495 		right = 100;
496 	spin_lock_irq(&dummy->mixer_lock);
497 	change = dummy->mixer_volume[addr][0] != left ||
498 	         dummy->mixer_volume[addr][1] != right;
499 	dummy->mixer_volume[addr][0] = left;
500 	dummy->mixer_volume[addr][1] = right;
501 	spin_unlock_irq(&dummy->mixer_lock);
502 	return change;
503 }
504 
505 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
506 
507 #define DUMMY_CAPSRC(xname, xindex, addr) \
508 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
509   .info = snd_dummy_capsrc_info, \
510   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
511   .private_value = addr }
512 
513 static int snd_dummy_capsrc_info(struct snd_kcontrol *kcontrol,
514 				 struct snd_ctl_elem_info *uinfo)
515 {
516 	uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
517 	uinfo->count = 2;
518 	uinfo->value.integer.min = 0;
519 	uinfo->value.integer.max = 1;
520 	return 0;
521 }
522 
523 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
524 				struct snd_ctl_elem_value *ucontrol)
525 {
526 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
527 	int addr = kcontrol->private_value;
528 
529 	spin_lock_irq(&dummy->mixer_lock);
530 	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
531 	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
532 	spin_unlock_irq(&dummy->mixer_lock);
533 	return 0;
534 }
535 
536 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
537 {
538 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
539 	int change, addr = kcontrol->private_value;
540 	int left, right;
541 
542 	left = ucontrol->value.integer.value[0] & 1;
543 	right = ucontrol->value.integer.value[1] & 1;
544 	spin_lock_irq(&dummy->mixer_lock);
545 	change = dummy->capture_source[addr][0] != left &&
546 	         dummy->capture_source[addr][1] != right;
547 	dummy->capture_source[addr][0] = left;
548 	dummy->capture_source[addr][1] = right;
549 	spin_unlock_irq(&dummy->mixer_lock);
550 	return change;
551 }
552 
553 static struct snd_kcontrol_new snd_dummy_controls[] = {
554 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
555 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
556 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
557 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
558 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
559 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
560 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
561 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
562 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
563 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
564 };
565 
566 static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
567 {
568 	struct snd_card *card = dummy->card;
569 	unsigned int idx;
570 	int err;
571 
572 	snd_assert(dummy != NULL, return -EINVAL);
573 	spin_lock_init(&dummy->mixer_lock);
574 	strcpy(card->mixername, "Dummy Mixer");
575 
576 	for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
577 		if ((err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy))) < 0)
578 			return err;
579 	}
580 	return 0;
581 }
582 
583 static int __devinit snd_dummy_probe(struct platform_device *devptr)
584 {
585 	struct snd_card *card;
586 	struct snd_dummy *dummy;
587 	int idx, err;
588 	int dev = devptr->id;
589 
590 	card = snd_card_new(index[dev], id[dev], THIS_MODULE,
591 			    sizeof(struct snd_dummy));
592 	if (card == NULL)
593 		return -ENOMEM;
594 	dummy = card->private_data;
595 	dummy->card = card;
596 	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
597 		if (pcm_substreams[dev] < 1)
598 			pcm_substreams[dev] = 1;
599 		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
600 			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
601 		if ((err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev])) < 0)
602 			goto __nodev;
603 	}
604 	if ((err = snd_card_dummy_new_mixer(dummy)) < 0)
605 		goto __nodev;
606 	strcpy(card->driver, "Dummy");
607 	strcpy(card->shortname, "Dummy");
608 	sprintf(card->longname, "Dummy %i", dev + 1);
609 
610 	snd_card_set_dev(card, &devptr->dev);
611 
612 	if ((err = snd_card_register(card)) == 0) {
613 		platform_set_drvdata(devptr, card);
614 		return 0;
615 	}
616       __nodev:
617 	snd_card_free(card);
618 	return err;
619 }
620 
621 static int __devexit snd_dummy_remove(struct platform_device *devptr)
622 {
623 	snd_card_free(platform_get_drvdata(devptr));
624 	platform_set_drvdata(devptr, NULL);
625 	return 0;
626 }
627 
628 #ifdef CONFIG_PM
629 static int snd_dummy_suspend(struct platform_device *pdev, pm_message_t state)
630 {
631 	struct snd_card *card = platform_get_drvdata(pdev);
632 	struct snd_dummy *dummy = card->private_data;
633 
634 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
635 	snd_pcm_suspend_all(dummy->pcm);
636 	return 0;
637 }
638 
639 static int snd_dummy_resume(struct platform_device *pdev)
640 {
641 	struct snd_card *card = platform_get_drvdata(pdev);
642 
643 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
644 	return 0;
645 }
646 #endif
647 
648 #define SND_DUMMY_DRIVER	"snd_dummy"
649 
650 static struct platform_driver snd_dummy_driver = {
651 	.probe		= snd_dummy_probe,
652 	.remove		= __devexit_p(snd_dummy_remove),
653 #ifdef CONFIG_PM
654 	.suspend	= snd_dummy_suspend,
655 	.resume		= snd_dummy_resume,
656 #endif
657 	.driver		= {
658 		.name	= SND_DUMMY_DRIVER
659 	},
660 };
661 
662 static void __init_or_module snd_dummy_unregister_all(void)
663 {
664 	int i;
665 
666 	for (i = 0; i < ARRAY_SIZE(devices); ++i)
667 		platform_device_unregister(devices[i]);
668 	platform_driver_unregister(&snd_dummy_driver);
669 }
670 
671 static int __init alsa_card_dummy_init(void)
672 {
673 	int i, cards, err;
674 
675 	if ((err = platform_driver_register(&snd_dummy_driver)) < 0)
676 		return err;
677 
678 	cards = 0;
679 	for (i = 0; i < SNDRV_CARDS; i++) {
680 		struct platform_device *device;
681 		if (! enable[i])
682 			continue;
683 		device = platform_device_register_simple(SND_DUMMY_DRIVER,
684 							 i, NULL, 0);
685 		if (IS_ERR(device))
686 			continue;
687 		if (!platform_get_drvdata(device)) {
688 			platform_device_unregister(device);
689 			continue;
690 		}
691 		devices[i] = device;
692 		cards++;
693 	}
694 	if (!cards) {
695 #ifdef MODULE
696 		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
697 #endif
698 		snd_dummy_unregister_all();
699 		return -ENODEV;
700 	}
701 	return 0;
702 }
703 
704 static void __exit alsa_card_dummy_exit(void)
705 {
706 	snd_dummy_unregister_all();
707 }
708 
709 module_init(alsa_card_dummy_init)
710 module_exit(alsa_card_dummy_exit)
711