xref: /openbmc/linux/sound/drivers/dummy.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  *  Dummy soundcard
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/init.h>
22 #include <linux/err.h>
23 #include <linux/platform_device.h>
24 #include <linux/jiffies.h>
25 #include <linux/slab.h>
26 #include <linux/time.h>
27 #include <linux/wait.h>
28 #include <linux/moduleparam.h>
29 #include <sound/core.h>
30 #include <sound/control.h>
31 #include <sound/tlv.h>
32 #include <sound/pcm.h>
33 #include <sound/rawmidi.h>
34 #include <sound/initval.h>
35 
36 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
37 MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
38 MODULE_LICENSE("GPL");
39 MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
40 
41 #define MAX_PCM_DEVICES		4
42 #define MAX_PCM_SUBSTREAMS	16
43 #define MAX_MIDI_DEVICES	2
44 
45 #if 0 /* emu10k1 emulation */
46 #define MAX_BUFFER_SIZE		(128 * 1024)
47 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
48 {
49 	int err;
50 	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
51 	if (err < 0)
52 		return err;
53 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
54 	if (err < 0)
55 		return err;
56 	return 0;
57 }
58 #define add_playback_constraints emu10k1_playback_constraints
59 #endif
60 
61 #if 0 /* RME9652 emulation */
62 #define MAX_BUFFER_SIZE		(26 * 64 * 1024)
63 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
64 #define USE_CHANNELS_MIN	26
65 #define USE_CHANNELS_MAX	26
66 #define USE_PERIODS_MIN		2
67 #define USE_PERIODS_MAX		2
68 #endif
69 
70 #if 0 /* ICE1712 emulation */
71 #define MAX_BUFFER_SIZE		(256 * 1024)
72 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
73 #define USE_CHANNELS_MIN	10
74 #define USE_CHANNELS_MAX	10
75 #define USE_PERIODS_MIN		1
76 #define USE_PERIODS_MAX		1024
77 #endif
78 
79 #if 0 /* UDA1341 emulation */
80 #define MAX_BUFFER_SIZE		(16380)
81 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
82 #define USE_CHANNELS_MIN	2
83 #define USE_CHANNELS_MAX	2
84 #define USE_PERIODS_MIN		2
85 #define USE_PERIODS_MAX		255
86 #endif
87 
88 #if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
89 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
90 #define USE_CHANNELS_MIN	2
91 #define USE_CHANNELS_MAX	2
92 #define USE_RATE		SNDRV_PCM_RATE_48000
93 #define USE_RATE_MIN		48000
94 #define USE_RATE_MAX		48000
95 #endif
96 
97 #if 0 /* CA0106 */
98 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
99 #define USE_CHANNELS_MIN	2
100 #define USE_CHANNELS_MAX	2
101 #define USE_RATE		(SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000)
102 #define USE_RATE_MIN		48000
103 #define USE_RATE_MAX		192000
104 #define MAX_BUFFER_SIZE		((65536-64)*8)
105 #define MAX_PERIOD_SIZE		(65536-64)
106 #define USE_PERIODS_MIN		2
107 #define USE_PERIODS_MAX		8
108 #endif
109 
110 
111 /* defaults */
112 #ifndef MAX_BUFFER_SIZE
113 #define MAX_BUFFER_SIZE		(64*1024)
114 #endif
115 #ifndef MAX_PERIOD_SIZE
116 #define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
117 #endif
118 #ifndef USE_FORMATS
119 #define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
120 #endif
121 #ifndef USE_RATE
122 #define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
123 #define USE_RATE_MIN		5500
124 #define USE_RATE_MAX		48000
125 #endif
126 #ifndef USE_CHANNELS_MIN
127 #define USE_CHANNELS_MIN 	1
128 #endif
129 #ifndef USE_CHANNELS_MAX
130 #define USE_CHANNELS_MAX 	2
131 #endif
132 #ifndef USE_PERIODS_MIN
133 #define USE_PERIODS_MIN 	1
134 #endif
135 #ifndef USE_PERIODS_MAX
136 #define USE_PERIODS_MAX 	1024
137 #endif
138 #ifndef add_playback_constraints
139 #define add_playback_constraints(x) 0
140 #endif
141 #ifndef add_capture_constraints
142 #define add_capture_constraints(x) 0
143 #endif
144 
145 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
146 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
147 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
148 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
149 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
150 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
151 
152 module_param_array(index, int, NULL, 0444);
153 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
154 module_param_array(id, charp, NULL, 0444);
155 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
156 module_param_array(enable, bool, NULL, 0444);
157 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
158 module_param_array(pcm_devs, int, NULL, 0444);
159 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
160 module_param_array(pcm_substreams, int, NULL, 0444);
161 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
162 //module_param_array(midi_devs, int, NULL, 0444);
163 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
164 
165 static struct platform_device *devices[SNDRV_CARDS];
166 
167 #define MIXER_ADDR_MASTER	0
168 #define MIXER_ADDR_LINE		1
169 #define MIXER_ADDR_MIC		2
170 #define MIXER_ADDR_SYNTH	3
171 #define MIXER_ADDR_CD		4
172 #define MIXER_ADDR_LAST		4
173 
174 struct snd_dummy {
175 	struct snd_card *card;
176 	struct snd_pcm *pcm;
177 	spinlock_t mixer_lock;
178 	int mixer_volume[MIXER_ADDR_LAST+1][2];
179 	int capture_source[MIXER_ADDR_LAST+1][2];
180 };
181 
182 struct snd_dummy_pcm {
183 	struct snd_dummy *dummy;
184 	spinlock_t lock;
185 	struct timer_list timer;
186 	unsigned int pcm_buffer_size;
187 	unsigned int pcm_period_size;
188 	unsigned int pcm_bps;		/* bytes per second */
189 	unsigned int pcm_hz;		/* HZ */
190 	unsigned int pcm_irq_pos;	/* IRQ position */
191 	unsigned int pcm_buf_pos;	/* position in buffer */
192 	struct snd_pcm_substream *substream;
193 };
194 
195 
196 static inline void snd_card_dummy_pcm_timer_start(struct snd_dummy_pcm *dpcm)
197 {
198 	dpcm->timer.expires = 1 + jiffies;
199 	add_timer(&dpcm->timer);
200 }
201 
202 static inline void snd_card_dummy_pcm_timer_stop(struct snd_dummy_pcm *dpcm)
203 {
204 	del_timer(&dpcm->timer);
205 }
206 
207 static int snd_card_dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
208 {
209 	struct snd_pcm_runtime *runtime = substream->runtime;
210 	struct snd_dummy_pcm *dpcm = runtime->private_data;
211 	int err = 0;
212 
213 	spin_lock(&dpcm->lock);
214 	switch (cmd) {
215 	case SNDRV_PCM_TRIGGER_START:
216 	case SNDRV_PCM_TRIGGER_RESUME:
217 		snd_card_dummy_pcm_timer_start(dpcm);
218 		break;
219 	case SNDRV_PCM_TRIGGER_STOP:
220 	case SNDRV_PCM_TRIGGER_SUSPEND:
221 		snd_card_dummy_pcm_timer_stop(dpcm);
222 		break;
223 	default:
224 		err = -EINVAL;
225 		break;
226 	}
227 	spin_unlock(&dpcm->lock);
228 	return 0;
229 }
230 
231 static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream)
232 {
233 	struct snd_pcm_runtime *runtime = substream->runtime;
234 	struct snd_dummy_pcm *dpcm = runtime->private_data;
235 	int bps;
236 
237 	bps = snd_pcm_format_width(runtime->format) * runtime->rate *
238 		runtime->channels / 8;
239 
240 	if (bps <= 0)
241 		return -EINVAL;
242 
243 	dpcm->pcm_bps = bps;
244 	dpcm->pcm_hz = HZ;
245 	dpcm->pcm_buffer_size = snd_pcm_lib_buffer_bytes(substream);
246 	dpcm->pcm_period_size = snd_pcm_lib_period_bytes(substream);
247 	dpcm->pcm_irq_pos = 0;
248 	dpcm->pcm_buf_pos = 0;
249 
250 	snd_pcm_format_set_silence(runtime->format, runtime->dma_area,
251 			bytes_to_samples(runtime, runtime->dma_bytes));
252 
253 	return 0;
254 }
255 
256 static void snd_card_dummy_pcm_timer_function(unsigned long data)
257 {
258 	struct snd_dummy_pcm *dpcm = (struct snd_dummy_pcm *)data;
259 	unsigned long flags;
260 
261 	spin_lock_irqsave(&dpcm->lock, flags);
262 	dpcm->timer.expires = 1 + jiffies;
263 	add_timer(&dpcm->timer);
264 	dpcm->pcm_irq_pos += dpcm->pcm_bps;
265 	dpcm->pcm_buf_pos += dpcm->pcm_bps;
266 	dpcm->pcm_buf_pos %= dpcm->pcm_buffer_size * dpcm->pcm_hz;
267 	if (dpcm->pcm_irq_pos >= dpcm->pcm_period_size * dpcm->pcm_hz) {
268 		dpcm->pcm_irq_pos %= dpcm->pcm_period_size * dpcm->pcm_hz;
269 		spin_unlock_irqrestore(&dpcm->lock, flags);
270 		snd_pcm_period_elapsed(dpcm->substream);
271 	} else
272 		spin_unlock_irqrestore(&dpcm->lock, flags);
273 }
274 
275 static snd_pcm_uframes_t snd_card_dummy_pcm_pointer(struct snd_pcm_substream *substream)
276 {
277 	struct snd_pcm_runtime *runtime = substream->runtime;
278 	struct snd_dummy_pcm *dpcm = runtime->private_data;
279 
280 	return bytes_to_frames(runtime, dpcm->pcm_buf_pos / dpcm->pcm_hz);
281 }
282 
283 static struct snd_pcm_hardware snd_card_dummy_playback =
284 {
285 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
286 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
287 	.formats =		USE_FORMATS,
288 	.rates =		USE_RATE,
289 	.rate_min =		USE_RATE_MIN,
290 	.rate_max =		USE_RATE_MAX,
291 	.channels_min =		USE_CHANNELS_MIN,
292 	.channels_max =		USE_CHANNELS_MAX,
293 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
294 	.period_bytes_min =	64,
295 	.period_bytes_max =	MAX_PERIOD_SIZE,
296 	.periods_min =		USE_PERIODS_MIN,
297 	.periods_max =		USE_PERIODS_MAX,
298 	.fifo_size =		0,
299 };
300 
301 static struct snd_pcm_hardware snd_card_dummy_capture =
302 {
303 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
304 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
305 	.formats =		USE_FORMATS,
306 	.rates =		USE_RATE,
307 	.rate_min =		USE_RATE_MIN,
308 	.rate_max =		USE_RATE_MAX,
309 	.channels_min =		USE_CHANNELS_MIN,
310 	.channels_max =		USE_CHANNELS_MAX,
311 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
312 	.period_bytes_min =	64,
313 	.period_bytes_max =	MAX_PERIOD_SIZE,
314 	.periods_min =		USE_PERIODS_MIN,
315 	.periods_max =		USE_PERIODS_MAX,
316 	.fifo_size =		0,
317 };
318 
319 static void snd_card_dummy_runtime_free(struct snd_pcm_runtime *runtime)
320 {
321 	kfree(runtime->private_data);
322 }
323 
324 static int snd_card_dummy_hw_params(struct snd_pcm_substream *substream,
325 				    struct snd_pcm_hw_params *hw_params)
326 {
327 	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
328 }
329 
330 static int snd_card_dummy_hw_free(struct snd_pcm_substream *substream)
331 {
332 	return snd_pcm_lib_free_pages(substream);
333 }
334 
335 static struct snd_dummy_pcm *new_pcm_stream(struct snd_pcm_substream *substream)
336 {
337 	struct snd_dummy_pcm *dpcm;
338 
339 	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
340 	if (! dpcm)
341 		return dpcm;
342 	init_timer(&dpcm->timer);
343 	dpcm->timer.data = (unsigned long) dpcm;
344 	dpcm->timer.function = snd_card_dummy_pcm_timer_function;
345 	spin_lock_init(&dpcm->lock);
346 	dpcm->substream = substream;
347 	return dpcm;
348 }
349 
350 static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream)
351 {
352 	struct snd_pcm_runtime *runtime = substream->runtime;
353 	struct snd_dummy_pcm *dpcm;
354 	int err;
355 
356 	if ((dpcm = new_pcm_stream(substream)) == NULL)
357 		return -ENOMEM;
358 	runtime->private_data = dpcm;
359 	/* makes the infrastructure responsible for freeing dpcm */
360 	runtime->private_free = snd_card_dummy_runtime_free;
361 	runtime->hw = snd_card_dummy_playback;
362 	if (substream->pcm->device & 1) {
363 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
364 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
365 	}
366 	if (substream->pcm->device & 2)
367 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
368 	err = add_playback_constraints(runtime);
369 	if (err < 0)
370 		return err;
371 
372 	return 0;
373 }
374 
375 static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream)
376 {
377 	struct snd_pcm_runtime *runtime = substream->runtime;
378 	struct snd_dummy_pcm *dpcm;
379 	int err;
380 
381 	if ((dpcm = new_pcm_stream(substream)) == NULL)
382 		return -ENOMEM;
383 	runtime->private_data = dpcm;
384 	/* makes the infrastructure responsible for freeing dpcm */
385 	runtime->private_free = snd_card_dummy_runtime_free;
386 	runtime->hw = snd_card_dummy_capture;
387 	if (substream->pcm->device == 1) {
388 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
389 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
390 	}
391 	if (substream->pcm->device & 2)
392 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
393 	err = add_capture_constraints(runtime);
394 	if (err < 0)
395 		return err;
396 
397 	return 0;
398 }
399 
400 static int snd_card_dummy_playback_close(struct snd_pcm_substream *substream)
401 {
402 	return 0;
403 }
404 
405 static int snd_card_dummy_capture_close(struct snd_pcm_substream *substream)
406 {
407 	return 0;
408 }
409 
410 static struct snd_pcm_ops snd_card_dummy_playback_ops = {
411 	.open =			snd_card_dummy_playback_open,
412 	.close =		snd_card_dummy_playback_close,
413 	.ioctl =		snd_pcm_lib_ioctl,
414 	.hw_params =		snd_card_dummy_hw_params,
415 	.hw_free =		snd_card_dummy_hw_free,
416 	.prepare =		snd_card_dummy_pcm_prepare,
417 	.trigger =		snd_card_dummy_pcm_trigger,
418 	.pointer =		snd_card_dummy_pcm_pointer,
419 };
420 
421 static struct snd_pcm_ops snd_card_dummy_capture_ops = {
422 	.open =			snd_card_dummy_capture_open,
423 	.close =		snd_card_dummy_capture_close,
424 	.ioctl =		snd_pcm_lib_ioctl,
425 	.hw_params =		snd_card_dummy_hw_params,
426 	.hw_free =		snd_card_dummy_hw_free,
427 	.prepare =		snd_card_dummy_pcm_prepare,
428 	.trigger =		snd_card_dummy_pcm_trigger,
429 	.pointer =		snd_card_dummy_pcm_pointer,
430 };
431 
432 static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
433 					int substreams)
434 {
435 	struct snd_pcm *pcm;
436 	int err;
437 
438 	err = snd_pcm_new(dummy->card, "Dummy PCM", device,
439 			       substreams, substreams, &pcm);
440 	if (err < 0)
441 		return err;
442 	dummy->pcm = pcm;
443 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_card_dummy_playback_ops);
444 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_dummy_capture_ops);
445 	pcm->private_data = dummy;
446 	pcm->info_flags = 0;
447 	strcpy(pcm->name, "Dummy PCM");
448 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
449 					      snd_dma_continuous_data(GFP_KERNEL),
450 					      0, 64*1024);
451 	return 0;
452 }
453 
454 #define DUMMY_VOLUME(xname, xindex, addr) \
455 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
456   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
457   .name = xname, .index = xindex, \
458   .info = snd_dummy_volume_info, \
459   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
460   .private_value = addr, \
461   .tlv = { .p = db_scale_dummy } }
462 
463 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
464 				 struct snd_ctl_elem_info *uinfo)
465 {
466 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
467 	uinfo->count = 2;
468 	uinfo->value.integer.min = -50;
469 	uinfo->value.integer.max = 100;
470 	return 0;
471 }
472 
473 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
474 				struct snd_ctl_elem_value *ucontrol)
475 {
476 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
477 	int addr = kcontrol->private_value;
478 
479 	spin_lock_irq(&dummy->mixer_lock);
480 	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
481 	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
482 	spin_unlock_irq(&dummy->mixer_lock);
483 	return 0;
484 }
485 
486 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
487 				struct snd_ctl_elem_value *ucontrol)
488 {
489 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
490 	int change, addr = kcontrol->private_value;
491 	int left, right;
492 
493 	left = ucontrol->value.integer.value[0];
494 	if (left < -50)
495 		left = -50;
496 	if (left > 100)
497 		left = 100;
498 	right = ucontrol->value.integer.value[1];
499 	if (right < -50)
500 		right = -50;
501 	if (right > 100)
502 		right = 100;
503 	spin_lock_irq(&dummy->mixer_lock);
504 	change = dummy->mixer_volume[addr][0] != left ||
505 	         dummy->mixer_volume[addr][1] != right;
506 	dummy->mixer_volume[addr][0] = left;
507 	dummy->mixer_volume[addr][1] = right;
508 	spin_unlock_irq(&dummy->mixer_lock);
509 	return change;
510 }
511 
512 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
513 
514 #define DUMMY_CAPSRC(xname, xindex, addr) \
515 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
516   .info = snd_dummy_capsrc_info, \
517   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
518   .private_value = addr }
519 
520 #define snd_dummy_capsrc_info	snd_ctl_boolean_stereo_info
521 
522 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
523 				struct snd_ctl_elem_value *ucontrol)
524 {
525 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
526 	int addr = kcontrol->private_value;
527 
528 	spin_lock_irq(&dummy->mixer_lock);
529 	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
530 	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
531 	spin_unlock_irq(&dummy->mixer_lock);
532 	return 0;
533 }
534 
535 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
536 {
537 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
538 	int change, addr = kcontrol->private_value;
539 	int left, right;
540 
541 	left = ucontrol->value.integer.value[0] & 1;
542 	right = ucontrol->value.integer.value[1] & 1;
543 	spin_lock_irq(&dummy->mixer_lock);
544 	change = dummy->capture_source[addr][0] != left &&
545 	         dummy->capture_source[addr][1] != right;
546 	dummy->capture_source[addr][0] = left;
547 	dummy->capture_source[addr][1] = right;
548 	spin_unlock_irq(&dummy->mixer_lock);
549 	return change;
550 }
551 
552 static struct snd_kcontrol_new snd_dummy_controls[] = {
553 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
554 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
555 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
556 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
557 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
558 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
559 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
560 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
561 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
562 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
563 };
564 
565 static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
566 {
567 	struct snd_card *card = dummy->card;
568 	unsigned int idx;
569 	int err;
570 
571 	if (snd_BUG_ON(!dummy))
572 		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 		err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy));
578 		if (err < 0)
579 			return err;
580 	}
581 	return 0;
582 }
583 
584 static int __devinit snd_dummy_probe(struct platform_device *devptr)
585 {
586 	struct snd_card *card;
587 	struct snd_dummy *dummy;
588 	int idx, err;
589 	int dev = devptr->id;
590 
591 	err = snd_card_create(index[dev], id[dev], THIS_MODULE,
592 			      sizeof(struct snd_dummy), &card);
593 	if (err < 0)
594 		return err;
595 	dummy = card->private_data;
596 	dummy->card = card;
597 	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
598 		if (pcm_substreams[dev] < 1)
599 			pcm_substreams[dev] = 1;
600 		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
601 			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
602 		err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
603 		if (err < 0)
604 			goto __nodev;
605 	}
606 	err = snd_card_dummy_new_mixer(dummy);
607 	if (err < 0)
608 		goto __nodev;
609 	strcpy(card->driver, "Dummy");
610 	strcpy(card->shortname, "Dummy");
611 	sprintf(card->longname, "Dummy %i", dev + 1);
612 
613 	snd_card_set_dev(card, &devptr->dev);
614 
615 	err = snd_card_register(card);
616 	if (err == 0) {
617 		platform_set_drvdata(devptr, card);
618 		return 0;
619 	}
620       __nodev:
621 	snd_card_free(card);
622 	return err;
623 }
624 
625 static int __devexit snd_dummy_remove(struct platform_device *devptr)
626 {
627 	snd_card_free(platform_get_drvdata(devptr));
628 	platform_set_drvdata(devptr, NULL);
629 	return 0;
630 }
631 
632 #ifdef CONFIG_PM
633 static int snd_dummy_suspend(struct platform_device *pdev, pm_message_t state)
634 {
635 	struct snd_card *card = platform_get_drvdata(pdev);
636 	struct snd_dummy *dummy = card->private_data;
637 
638 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
639 	snd_pcm_suspend_all(dummy->pcm);
640 	return 0;
641 }
642 
643 static int snd_dummy_resume(struct platform_device *pdev)
644 {
645 	struct snd_card *card = platform_get_drvdata(pdev);
646 
647 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
648 	return 0;
649 }
650 #endif
651 
652 #define SND_DUMMY_DRIVER	"snd_dummy"
653 
654 static struct platform_driver snd_dummy_driver = {
655 	.probe		= snd_dummy_probe,
656 	.remove		= __devexit_p(snd_dummy_remove),
657 #ifdef CONFIG_PM
658 	.suspend	= snd_dummy_suspend,
659 	.resume		= snd_dummy_resume,
660 #endif
661 	.driver		= {
662 		.name	= SND_DUMMY_DRIVER
663 	},
664 };
665 
666 static void snd_dummy_unregister_all(void)
667 {
668 	int i;
669 
670 	for (i = 0; i < ARRAY_SIZE(devices); ++i)
671 		platform_device_unregister(devices[i]);
672 	platform_driver_unregister(&snd_dummy_driver);
673 }
674 
675 static int __init alsa_card_dummy_init(void)
676 {
677 	int i, cards, err;
678 
679 	err = platform_driver_register(&snd_dummy_driver);
680 	if (err < 0)
681 		return err;
682 
683 	cards = 0;
684 	for (i = 0; i < SNDRV_CARDS; i++) {
685 		struct platform_device *device;
686 		if (! enable[i])
687 			continue;
688 		device = platform_device_register_simple(SND_DUMMY_DRIVER,
689 							 i, NULL, 0);
690 		if (IS_ERR(device))
691 			continue;
692 		if (!platform_get_drvdata(device)) {
693 			platform_device_unregister(device);
694 			continue;
695 		}
696 		devices[i] = device;
697 		cards++;
698 	}
699 	if (!cards) {
700 #ifdef MODULE
701 		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
702 #endif
703 		snd_dummy_unregister_all();
704 		return -ENODEV;
705 	}
706 	return 0;
707 }
708 
709 static void __exit alsa_card_dummy_exit(void)
710 {
711 	snd_dummy_unregister_all();
712 }
713 
714 module_init(alsa_card_dummy_init)
715 module_exit(alsa_card_dummy_exit)
716