xref: /openbmc/linux/sound/drivers/dummy.c (revision 384740dc)
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 	if ((err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
51 		return err;
52 	if ((err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX)) < 0)
53 		return err;
54 	return 0;
55 }
56 #define add_playback_constraints emu10k1_playback_constraints
57 #endif
58 
59 #if 0 /* RME9652 emulation */
60 #define MAX_BUFFER_SIZE		(26 * 64 * 1024)
61 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
62 #define USE_CHANNELS_MIN	26
63 #define USE_CHANNELS_MAX	26
64 #define USE_PERIODS_MIN		2
65 #define USE_PERIODS_MAX		2
66 #endif
67 
68 #if 0 /* ICE1712 emulation */
69 #define MAX_BUFFER_SIZE		(256 * 1024)
70 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S32_LE
71 #define USE_CHANNELS_MIN	10
72 #define USE_CHANNELS_MAX	10
73 #define USE_PERIODS_MIN		1
74 #define USE_PERIODS_MAX		1024
75 #endif
76 
77 #if 0 /* UDA1341 emulation */
78 #define MAX_BUFFER_SIZE		(16380)
79 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
80 #define USE_CHANNELS_MIN	2
81 #define USE_CHANNELS_MAX	2
82 #define USE_PERIODS_MIN		2
83 #define USE_PERIODS_MAX		255
84 #endif
85 
86 #if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
87 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
88 #define USE_CHANNELS_MIN	2
89 #define USE_CHANNELS_MAX	2
90 #define USE_RATE		SNDRV_PCM_RATE_48000
91 #define USE_RATE_MIN		48000
92 #define USE_RATE_MAX		48000
93 #endif
94 
95 #if 0 /* CA0106 */
96 #define USE_FORMATS		SNDRV_PCM_FMTBIT_S16_LE
97 #define USE_CHANNELS_MIN	2
98 #define USE_CHANNELS_MAX	2
99 #define USE_RATE		(SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000)
100 #define USE_RATE_MIN		48000
101 #define USE_RATE_MAX		192000
102 #define MAX_BUFFER_SIZE		((65536-64)*8)
103 #define MAX_PERIOD_SIZE		(65536-64)
104 #define USE_PERIODS_MIN		2
105 #define USE_PERIODS_MAX		8
106 #endif
107 
108 
109 /* defaults */
110 #ifndef MAX_BUFFER_SIZE
111 #define MAX_BUFFER_SIZE		(64*1024)
112 #endif
113 #ifndef MAX_PERIOD_SIZE
114 #define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
115 #endif
116 #ifndef USE_FORMATS
117 #define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
118 #endif
119 #ifndef USE_RATE
120 #define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
121 #define USE_RATE_MIN		5500
122 #define USE_RATE_MAX		48000
123 #endif
124 #ifndef USE_CHANNELS_MIN
125 #define USE_CHANNELS_MIN 	1
126 #endif
127 #ifndef USE_CHANNELS_MAX
128 #define USE_CHANNELS_MAX 	2
129 #endif
130 #ifndef USE_PERIODS_MIN
131 #define USE_PERIODS_MIN 	1
132 #endif
133 #ifndef USE_PERIODS_MAX
134 #define USE_PERIODS_MAX 	1024
135 #endif
136 #ifndef add_playback_constraints
137 #define add_playback_constraints(x) 0
138 #endif
139 #ifndef add_capture_constraints
140 #define add_capture_constraints(x) 0
141 #endif
142 
143 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
144 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
145 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
146 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
147 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
148 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
149 
150 module_param_array(index, int, NULL, 0444);
151 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
152 module_param_array(id, charp, NULL, 0444);
153 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
154 module_param_array(enable, bool, NULL, 0444);
155 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
156 module_param_array(pcm_devs, int, NULL, 0444);
157 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
158 module_param_array(pcm_substreams, int, NULL, 0444);
159 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
160 //module_param_array(midi_devs, int, NULL, 0444);
161 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
162 
163 static struct platform_device *devices[SNDRV_CARDS];
164 
165 #define MIXER_ADDR_MASTER	0
166 #define MIXER_ADDR_LINE		1
167 #define MIXER_ADDR_MIC		2
168 #define MIXER_ADDR_SYNTH	3
169 #define MIXER_ADDR_CD		4
170 #define MIXER_ADDR_LAST		4
171 
172 struct snd_dummy {
173 	struct snd_card *card;
174 	struct snd_pcm *pcm;
175 	spinlock_t mixer_lock;
176 	int mixer_volume[MIXER_ADDR_LAST+1][2];
177 	int capture_source[MIXER_ADDR_LAST+1][2];
178 };
179 
180 struct snd_dummy_pcm {
181 	struct snd_dummy *dummy;
182 	spinlock_t lock;
183 	struct timer_list timer;
184 	unsigned int pcm_buffer_size;
185 	unsigned int pcm_period_size;
186 	unsigned int pcm_bps;		/* bytes per second */
187 	unsigned int pcm_hz;		/* HZ */
188 	unsigned int pcm_irq_pos;	/* IRQ position */
189 	unsigned int pcm_buf_pos;	/* position in buffer */
190 	struct snd_pcm_substream *substream;
191 };
192 
193 
194 static inline void snd_card_dummy_pcm_timer_start(struct snd_dummy_pcm *dpcm)
195 {
196 	dpcm->timer.expires = 1 + jiffies;
197 	add_timer(&dpcm->timer);
198 }
199 
200 static inline void snd_card_dummy_pcm_timer_stop(struct snd_dummy_pcm *dpcm)
201 {
202 	del_timer(&dpcm->timer);
203 }
204 
205 static int snd_card_dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
206 {
207 	struct snd_pcm_runtime *runtime = substream->runtime;
208 	struct snd_dummy_pcm *dpcm = runtime->private_data;
209 	int err = 0;
210 
211 	spin_lock(&dpcm->lock);
212 	switch (cmd) {
213 	case SNDRV_PCM_TRIGGER_START:
214 	case SNDRV_PCM_TRIGGER_RESUME:
215 		snd_card_dummy_pcm_timer_start(dpcm);
216 		break;
217 	case SNDRV_PCM_TRIGGER_STOP:
218 	case SNDRV_PCM_TRIGGER_SUSPEND:
219 		snd_card_dummy_pcm_timer_stop(dpcm);
220 		break;
221 	default:
222 		err = -EINVAL;
223 		break;
224 	}
225 	spin_unlock(&dpcm->lock);
226 	return 0;
227 }
228 
229 static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream)
230 {
231 	struct snd_pcm_runtime *runtime = substream->runtime;
232 	struct snd_dummy_pcm *dpcm = runtime->private_data;
233 	int bps;
234 
235 	bps = snd_pcm_format_width(runtime->format) * runtime->rate *
236 		runtime->channels / 8;
237 
238 	if (bps <= 0)
239 		return -EINVAL;
240 
241 	dpcm->pcm_bps = bps;
242 	dpcm->pcm_hz = HZ;
243 	dpcm->pcm_buffer_size = snd_pcm_lib_buffer_bytes(substream);
244 	dpcm->pcm_period_size = snd_pcm_lib_period_bytes(substream);
245 	dpcm->pcm_irq_pos = 0;
246 	dpcm->pcm_buf_pos = 0;
247 
248 	snd_pcm_format_set_silence(runtime->format, runtime->dma_area,
249 			bytes_to_samples(runtime, runtime->dma_bytes));
250 
251 	return 0;
252 }
253 
254 static void snd_card_dummy_pcm_timer_function(unsigned long data)
255 {
256 	struct snd_dummy_pcm *dpcm = (struct snd_dummy_pcm *)data;
257 	unsigned long flags;
258 
259 	spin_lock_irqsave(&dpcm->lock, flags);
260 	dpcm->timer.expires = 1 + jiffies;
261 	add_timer(&dpcm->timer);
262 	dpcm->pcm_irq_pos += dpcm->pcm_bps;
263 	dpcm->pcm_buf_pos += dpcm->pcm_bps;
264 	dpcm->pcm_buf_pos %= dpcm->pcm_buffer_size * dpcm->pcm_hz;
265 	if (dpcm->pcm_irq_pos >= dpcm->pcm_period_size * dpcm->pcm_hz) {
266 		dpcm->pcm_irq_pos %= dpcm->pcm_period_size * dpcm->pcm_hz;
267 		spin_unlock_irqrestore(&dpcm->lock, flags);
268 		snd_pcm_period_elapsed(dpcm->substream);
269 	} else
270 		spin_unlock_irqrestore(&dpcm->lock, flags);
271 }
272 
273 static snd_pcm_uframes_t snd_card_dummy_pcm_pointer(struct snd_pcm_substream *substream)
274 {
275 	struct snd_pcm_runtime *runtime = substream->runtime;
276 	struct snd_dummy_pcm *dpcm = runtime->private_data;
277 
278 	return bytes_to_frames(runtime, dpcm->pcm_buf_pos / dpcm->pcm_hz);
279 }
280 
281 static struct snd_pcm_hardware snd_card_dummy_playback =
282 {
283 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
284 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
285 	.formats =		USE_FORMATS,
286 	.rates =		USE_RATE,
287 	.rate_min =		USE_RATE_MIN,
288 	.rate_max =		USE_RATE_MAX,
289 	.channels_min =		USE_CHANNELS_MIN,
290 	.channels_max =		USE_CHANNELS_MAX,
291 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
292 	.period_bytes_min =	64,
293 	.period_bytes_max =	MAX_PERIOD_SIZE,
294 	.periods_min =		USE_PERIODS_MIN,
295 	.periods_max =		USE_PERIODS_MAX,
296 	.fifo_size =		0,
297 };
298 
299 static struct snd_pcm_hardware snd_card_dummy_capture =
300 {
301 	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
302 				 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_MMAP_VALID),
303 	.formats =		USE_FORMATS,
304 	.rates =		USE_RATE,
305 	.rate_min =		USE_RATE_MIN,
306 	.rate_max =		USE_RATE_MAX,
307 	.channels_min =		USE_CHANNELS_MIN,
308 	.channels_max =		USE_CHANNELS_MAX,
309 	.buffer_bytes_max =	MAX_BUFFER_SIZE,
310 	.period_bytes_min =	64,
311 	.period_bytes_max =	MAX_PERIOD_SIZE,
312 	.periods_min =		USE_PERIODS_MIN,
313 	.periods_max =		USE_PERIODS_MAX,
314 	.fifo_size =		0,
315 };
316 
317 static void snd_card_dummy_runtime_free(struct snd_pcm_runtime *runtime)
318 {
319 	kfree(runtime->private_data);
320 }
321 
322 static int snd_card_dummy_hw_params(struct snd_pcm_substream *substream,
323 				    struct snd_pcm_hw_params *hw_params)
324 {
325 	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
326 }
327 
328 static int snd_card_dummy_hw_free(struct snd_pcm_substream *substream)
329 {
330 	return snd_pcm_lib_free_pages(substream);
331 }
332 
333 static struct snd_dummy_pcm *new_pcm_stream(struct snd_pcm_substream *substream)
334 {
335 	struct snd_dummy_pcm *dpcm;
336 
337 	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
338 	if (! dpcm)
339 		return dpcm;
340 	init_timer(&dpcm->timer);
341 	dpcm->timer.data = (unsigned long) dpcm;
342 	dpcm->timer.function = snd_card_dummy_pcm_timer_function;
343 	spin_lock_init(&dpcm->lock);
344 	dpcm->substream = substream;
345 	return dpcm;
346 }
347 
348 static int snd_card_dummy_playback_open(struct snd_pcm_substream *substream)
349 {
350 	struct snd_pcm_runtime *runtime = substream->runtime;
351 	struct snd_dummy_pcm *dpcm;
352 	int err;
353 
354 	if ((dpcm = new_pcm_stream(substream)) == NULL)
355 		return -ENOMEM;
356 	runtime->private_data = dpcm;
357 	runtime->private_free = snd_card_dummy_runtime_free;
358 	runtime->hw = snd_card_dummy_playback;
359 	if (substream->pcm->device & 1) {
360 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
361 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
362 	}
363 	if (substream->pcm->device & 2)
364 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
365 	if ((err = add_playback_constraints(runtime)) < 0) {
366 		kfree(dpcm);
367 		return err;
368 	}
369 
370 	return 0;
371 }
372 
373 static int snd_card_dummy_capture_open(struct snd_pcm_substream *substream)
374 {
375 	struct snd_pcm_runtime *runtime = substream->runtime;
376 	struct snd_dummy_pcm *dpcm;
377 	int err;
378 
379 	if ((dpcm = new_pcm_stream(substream)) == NULL)
380 		return -ENOMEM;
381 	runtime->private_data = dpcm;
382 	runtime->private_free = snd_card_dummy_runtime_free;
383 	runtime->hw = snd_card_dummy_capture;
384 	if (substream->pcm->device == 1) {
385 		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
386 		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
387 	}
388 	if (substream->pcm->device & 2)
389 		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP|SNDRV_PCM_INFO_MMAP_VALID);
390 	if ((err = add_capture_constraints(runtime)) < 0) {
391 		kfree(dpcm);
392 		return err;
393 	}
394 
395 	return 0;
396 }
397 
398 static int snd_card_dummy_playback_close(struct snd_pcm_substream *substream)
399 {
400 	return 0;
401 }
402 
403 static int snd_card_dummy_capture_close(struct snd_pcm_substream *substream)
404 {
405 	return 0;
406 }
407 
408 static struct snd_pcm_ops snd_card_dummy_playback_ops = {
409 	.open =			snd_card_dummy_playback_open,
410 	.close =		snd_card_dummy_playback_close,
411 	.ioctl =		snd_pcm_lib_ioctl,
412 	.hw_params =		snd_card_dummy_hw_params,
413 	.hw_free =		snd_card_dummy_hw_free,
414 	.prepare =		snd_card_dummy_pcm_prepare,
415 	.trigger =		snd_card_dummy_pcm_trigger,
416 	.pointer =		snd_card_dummy_pcm_pointer,
417 };
418 
419 static struct snd_pcm_ops snd_card_dummy_capture_ops = {
420 	.open =			snd_card_dummy_capture_open,
421 	.close =		snd_card_dummy_capture_close,
422 	.ioctl =		snd_pcm_lib_ioctl,
423 	.hw_params =		snd_card_dummy_hw_params,
424 	.hw_free =		snd_card_dummy_hw_free,
425 	.prepare =		snd_card_dummy_pcm_prepare,
426 	.trigger =		snd_card_dummy_pcm_trigger,
427 	.pointer =		snd_card_dummy_pcm_pointer,
428 };
429 
430 static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
431 					int substreams)
432 {
433 	struct snd_pcm *pcm;
434 	int err;
435 
436 	if ((err = snd_pcm_new(dummy->card, "Dummy PCM", device,
437 			       substreams, substreams, &pcm)) < 0)
438 		return err;
439 	dummy->pcm = pcm;
440 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_card_dummy_playback_ops);
441 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_card_dummy_capture_ops);
442 	pcm->private_data = dummy;
443 	pcm->info_flags = 0;
444 	strcpy(pcm->name, "Dummy PCM");
445 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
446 					      snd_dma_continuous_data(GFP_KERNEL),
447 					      0, 64*1024);
448 	return 0;
449 }
450 
451 #define DUMMY_VOLUME(xname, xindex, addr) \
452 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
453   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
454   .name = xname, .index = xindex, \
455   .info = snd_dummy_volume_info, \
456   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
457   .private_value = addr, \
458   .tlv = { .p = db_scale_dummy } }
459 
460 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
461 				 struct snd_ctl_elem_info *uinfo)
462 {
463 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
464 	uinfo->count = 2;
465 	uinfo->value.integer.min = -50;
466 	uinfo->value.integer.max = 100;
467 	return 0;
468 }
469 
470 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
471 				struct snd_ctl_elem_value *ucontrol)
472 {
473 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
474 	int addr = kcontrol->private_value;
475 
476 	spin_lock_irq(&dummy->mixer_lock);
477 	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
478 	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
479 	spin_unlock_irq(&dummy->mixer_lock);
480 	return 0;
481 }
482 
483 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
484 				struct snd_ctl_elem_value *ucontrol)
485 {
486 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
487 	int change, addr = kcontrol->private_value;
488 	int left, right;
489 
490 	left = ucontrol->value.integer.value[0];
491 	if (left < -50)
492 		left = -50;
493 	if (left > 100)
494 		left = 100;
495 	right = ucontrol->value.integer.value[1];
496 	if (right < -50)
497 		right = -50;
498 	if (right > 100)
499 		right = 100;
500 	spin_lock_irq(&dummy->mixer_lock);
501 	change = dummy->mixer_volume[addr][0] != left ||
502 	         dummy->mixer_volume[addr][1] != right;
503 	dummy->mixer_volume[addr][0] = left;
504 	dummy->mixer_volume[addr][1] = right;
505 	spin_unlock_irq(&dummy->mixer_lock);
506 	return change;
507 }
508 
509 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
510 
511 #define DUMMY_CAPSRC(xname, xindex, addr) \
512 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
513   .info = snd_dummy_capsrc_info, \
514   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
515   .private_value = addr }
516 
517 #define snd_dummy_capsrc_info	snd_ctl_boolean_stereo_info
518 
519 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
520 				struct snd_ctl_elem_value *ucontrol)
521 {
522 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
523 	int addr = kcontrol->private_value;
524 
525 	spin_lock_irq(&dummy->mixer_lock);
526 	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
527 	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
528 	spin_unlock_irq(&dummy->mixer_lock);
529 	return 0;
530 }
531 
532 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
533 {
534 	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
535 	int change, addr = kcontrol->private_value;
536 	int left, right;
537 
538 	left = ucontrol->value.integer.value[0] & 1;
539 	right = ucontrol->value.integer.value[1] & 1;
540 	spin_lock_irq(&dummy->mixer_lock);
541 	change = dummy->capture_source[addr][0] != left &&
542 	         dummy->capture_source[addr][1] != right;
543 	dummy->capture_source[addr][0] = left;
544 	dummy->capture_source[addr][1] = right;
545 	spin_unlock_irq(&dummy->mixer_lock);
546 	return change;
547 }
548 
549 static struct snd_kcontrol_new snd_dummy_controls[] = {
550 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
551 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
552 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
553 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
554 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
555 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
556 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
557 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
558 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
559 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
560 };
561 
562 static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
563 {
564 	struct snd_card *card = dummy->card;
565 	unsigned int idx;
566 	int err;
567 
568 	snd_assert(dummy != NULL, return -EINVAL);
569 	spin_lock_init(&dummy->mixer_lock);
570 	strcpy(card->mixername, "Dummy Mixer");
571 
572 	for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
573 		if ((err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy))) < 0)
574 			return err;
575 	}
576 	return 0;
577 }
578 
579 static int __devinit snd_dummy_probe(struct platform_device *devptr)
580 {
581 	struct snd_card *card;
582 	struct snd_dummy *dummy;
583 	int idx, err;
584 	int dev = devptr->id;
585 
586 	card = snd_card_new(index[dev], id[dev], THIS_MODULE,
587 			    sizeof(struct snd_dummy));
588 	if (card == NULL)
589 		return -ENOMEM;
590 	dummy = card->private_data;
591 	dummy->card = card;
592 	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
593 		if (pcm_substreams[dev] < 1)
594 			pcm_substreams[dev] = 1;
595 		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
596 			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
597 		if ((err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev])) < 0)
598 			goto __nodev;
599 	}
600 	if ((err = snd_card_dummy_new_mixer(dummy)) < 0)
601 		goto __nodev;
602 	strcpy(card->driver, "Dummy");
603 	strcpy(card->shortname, "Dummy");
604 	sprintf(card->longname, "Dummy %i", dev + 1);
605 
606 	snd_card_set_dev(card, &devptr->dev);
607 
608 	if ((err = snd_card_register(card)) == 0) {
609 		platform_set_drvdata(devptr, card);
610 		return 0;
611 	}
612       __nodev:
613 	snd_card_free(card);
614 	return err;
615 }
616 
617 static int __devexit snd_dummy_remove(struct platform_device *devptr)
618 {
619 	snd_card_free(platform_get_drvdata(devptr));
620 	platform_set_drvdata(devptr, NULL);
621 	return 0;
622 }
623 
624 #ifdef CONFIG_PM
625 static int snd_dummy_suspend(struct platform_device *pdev, pm_message_t state)
626 {
627 	struct snd_card *card = platform_get_drvdata(pdev);
628 	struct snd_dummy *dummy = card->private_data;
629 
630 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
631 	snd_pcm_suspend_all(dummy->pcm);
632 	return 0;
633 }
634 
635 static int snd_dummy_resume(struct platform_device *pdev)
636 {
637 	struct snd_card *card = platform_get_drvdata(pdev);
638 
639 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
640 	return 0;
641 }
642 #endif
643 
644 #define SND_DUMMY_DRIVER	"snd_dummy"
645 
646 static struct platform_driver snd_dummy_driver = {
647 	.probe		= snd_dummy_probe,
648 	.remove		= __devexit_p(snd_dummy_remove),
649 #ifdef CONFIG_PM
650 	.suspend	= snd_dummy_suspend,
651 	.resume		= snd_dummy_resume,
652 #endif
653 	.driver		= {
654 		.name	= SND_DUMMY_DRIVER
655 	},
656 };
657 
658 static void snd_dummy_unregister_all(void)
659 {
660 	int i;
661 
662 	for (i = 0; i < ARRAY_SIZE(devices); ++i)
663 		platform_device_unregister(devices[i]);
664 	platform_driver_unregister(&snd_dummy_driver);
665 }
666 
667 static int __init alsa_card_dummy_init(void)
668 {
669 	int i, cards, err;
670 
671 	if ((err = platform_driver_register(&snd_dummy_driver)) < 0)
672 		return err;
673 
674 	cards = 0;
675 	for (i = 0; i < SNDRV_CARDS; i++) {
676 		struct platform_device *device;
677 		if (! enable[i])
678 			continue;
679 		device = platform_device_register_simple(SND_DUMMY_DRIVER,
680 							 i, NULL, 0);
681 		if (IS_ERR(device))
682 			continue;
683 		if (!platform_get_drvdata(device)) {
684 			platform_device_unregister(device);
685 			continue;
686 		}
687 		devices[i] = device;
688 		cards++;
689 	}
690 	if (!cards) {
691 #ifdef MODULE
692 		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
693 #endif
694 		snd_dummy_unregister_all();
695 		return -ENODEV;
696 	}
697 	return 0;
698 }
699 
700 static void __exit alsa_card_dummy_exit(void)
701 {
702 	snd_dummy_unregister_all();
703 }
704 
705 module_init(alsa_card_dummy_init)
706 module_exit(alsa_card_dummy_exit)
707