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v3.15
 
   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/hrtimer.h>
  29#include <linux/math64.h>
  30#include <linux/module.h>
  31#include <sound/core.h>
  32#include <sound/control.h>
  33#include <sound/tlv.h>
  34#include <sound/pcm.h>
  35#include <sound/rawmidi.h>
  36#include <sound/info.h>
  37#include <sound/initval.h>
  38
  39MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  40MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  41MODULE_LICENSE("GPL");
  42MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
  43
  44#define MAX_PCM_DEVICES		4
  45#define MAX_PCM_SUBSTREAMS	128
  46#define MAX_MIDI_DEVICES	2
  47
  48/* defaults */
  49#define MAX_BUFFER_SIZE		(64*1024)
  50#define MIN_PERIOD_SIZE		64
  51#define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
  52#define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
  53#define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
  54#define USE_RATE_MIN		5500
  55#define USE_RATE_MAX		48000
  56#define USE_CHANNELS_MIN 	1
  57#define USE_CHANNELS_MAX 	2
  58#define USE_PERIODS_MIN 	1
  59#define USE_PERIODS_MAX 	1024
 
 
  60
  61static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
  62static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
  63static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  64static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  65static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  66static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
  67//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
 
 
  68#ifdef CONFIG_HIGH_RES_TIMERS
  69static bool hrtimer = 1;
  70#endif
  71static bool fake_buffer = 1;
  72
  73module_param_array(index, int, NULL, 0444);
  74MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  75module_param_array(id, charp, NULL, 0444);
  76MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  77module_param_array(enable, bool, NULL, 0444);
  78MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  79module_param_array(model, charp, NULL, 0444);
  80MODULE_PARM_DESC(model, "Soundcard model.");
  81module_param_array(pcm_devs, int, NULL, 0444);
  82MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  83module_param_array(pcm_substreams, int, NULL, 0444);
  84MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
  85//module_param_array(midi_devs, int, NULL, 0444);
  86//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
 
 
 
 
  87module_param(fake_buffer, bool, 0444);
  88MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  89#ifdef CONFIG_HIGH_RES_TIMERS
  90module_param(hrtimer, bool, 0644);
  91MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  92#endif
  93
  94static struct platform_device *devices[SNDRV_CARDS];
  95
  96#define MIXER_ADDR_MASTER	0
  97#define MIXER_ADDR_LINE		1
  98#define MIXER_ADDR_MIC		2
  99#define MIXER_ADDR_SYNTH	3
 100#define MIXER_ADDR_CD		4
 101#define MIXER_ADDR_LAST		4
 102
 103struct dummy_timer_ops {
 104	int (*create)(struct snd_pcm_substream *);
 105	void (*free)(struct snd_pcm_substream *);
 106	int (*prepare)(struct snd_pcm_substream *);
 107	int (*start)(struct snd_pcm_substream *);
 108	int (*stop)(struct snd_pcm_substream *);
 109	snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
 110};
 111
 
 
 
 112struct dummy_model {
 113	const char *name;
 114	int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 115	int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 116	u64 formats;
 117	size_t buffer_bytes_max;
 118	size_t period_bytes_min;
 119	size_t period_bytes_max;
 120	unsigned int periods_min;
 121	unsigned int periods_max;
 122	unsigned int rates;
 123	unsigned int rate_min;
 124	unsigned int rate_max;
 125	unsigned int channels_min;
 126	unsigned int channels_max;
 127};
 128
 129struct snd_dummy {
 130	struct snd_card *card;
 131	struct dummy_model *model;
 132	struct snd_pcm *pcm;
 133	struct snd_pcm_hardware pcm_hw;
 134	spinlock_t mixer_lock;
 135	int mixer_volume[MIXER_ADDR_LAST+1][2];
 136	int capture_source[MIXER_ADDR_LAST+1][2];
 137	int iobox;
 138	struct snd_kcontrol *cd_volume_ctl;
 139	struct snd_kcontrol *cd_switch_ctl;
 140	const struct dummy_timer_ops *timer_ops;
 141};
 142
 143/*
 144 * card models
 145 */
 146
 147static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 148{
 149	int err;
 150	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 151	if (err < 0)
 152		return err;
 153	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 154	if (err < 0)
 155		return err;
 156	return 0;
 157}
 158
 159struct dummy_model model_emu10k1 = {
 160	.name = "emu10k1",
 161	.playback_constraints = emu10k1_playback_constraints,
 162	.buffer_bytes_max = 128 * 1024,
 163};
 164
 165struct dummy_model model_rme9652 = {
 166	.name = "rme9652",
 167	.buffer_bytes_max = 26 * 64 * 1024,
 168	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 169	.channels_min = 26,
 170	.channels_max = 26,
 171	.periods_min = 2,
 172	.periods_max = 2,
 173};
 174
 175struct dummy_model model_ice1712 = {
 176	.name = "ice1712",
 177	.buffer_bytes_max = 256 * 1024,
 178	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 179	.channels_min = 10,
 180	.channels_max = 10,
 181	.periods_min = 1,
 182	.periods_max = 1024,
 183};
 184
 185struct dummy_model model_uda1341 = {
 186	.name = "uda1341",
 187	.buffer_bytes_max = 16380,
 188	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 189	.channels_min = 2,
 190	.channels_max = 2,
 191	.periods_min = 2,
 192	.periods_max = 255,
 193};
 194
 195struct dummy_model model_ac97 = {
 196	.name = "ac97",
 197	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 198	.channels_min = 2,
 199	.channels_max = 2,
 200	.rates = SNDRV_PCM_RATE_48000,
 201	.rate_min = 48000,
 202	.rate_max = 48000,
 203};
 204
 205struct dummy_model model_ca0106 = {
 206	.name = "ca0106",
 207	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 208	.buffer_bytes_max = ((65536-64)*8),
 209	.period_bytes_max = (65536-64),
 210	.periods_min = 2,
 211	.periods_max = 8,
 212	.channels_min = 2,
 213	.channels_max = 2,
 214	.rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 215	.rate_min = 48000,
 216	.rate_max = 192000,
 217};
 218
 219struct dummy_model *dummy_models[] = {
 220	&model_emu10k1,
 221	&model_rme9652,
 222	&model_ice1712,
 223	&model_uda1341,
 224	&model_ac97,
 225	&model_ca0106,
 226	NULL
 227};
 228
 229/*
 230 * system timer interface
 231 */
 232
 233struct dummy_systimer_pcm {
 
 
 234	spinlock_t lock;
 235	struct timer_list timer;
 236	unsigned long base_time;
 237	unsigned int frac_pos;	/* fractional sample position (based HZ) */
 238	unsigned int frac_period_rest;
 239	unsigned int frac_buffer_size;	/* buffer_size * HZ */
 240	unsigned int frac_period_size;	/* period_size * HZ */
 241	unsigned int rate;
 242	int elapsed;
 243	struct snd_pcm_substream *substream;
 244};
 245
 246static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 247{
 248	dpcm->timer.expires = jiffies +
 249		(dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate;
 250	add_timer(&dpcm->timer);
 251}
 252
 253static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 254{
 255	unsigned long delta;
 256
 257	delta = jiffies - dpcm->base_time;
 258	if (!delta)
 259		return;
 260	dpcm->base_time += delta;
 261	delta *= dpcm->rate;
 262	dpcm->frac_pos += delta;
 263	while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 264		dpcm->frac_pos -= dpcm->frac_buffer_size;
 265	while (dpcm->frac_period_rest <= delta) {
 266		dpcm->elapsed++;
 267		dpcm->frac_period_rest += dpcm->frac_period_size;
 268	}
 269	dpcm->frac_period_rest -= delta;
 270}
 271
 272static int dummy_systimer_start(struct snd_pcm_substream *substream)
 273{
 274	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 275	spin_lock(&dpcm->lock);
 276	dpcm->base_time = jiffies;
 277	dummy_systimer_rearm(dpcm);
 278	spin_unlock(&dpcm->lock);
 279	return 0;
 280}
 281
 282static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 283{
 284	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 285	spin_lock(&dpcm->lock);
 286	del_timer(&dpcm->timer);
 287	spin_unlock(&dpcm->lock);
 288	return 0;
 289}
 290
 291static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 292{
 293	struct snd_pcm_runtime *runtime = substream->runtime;
 294	struct dummy_systimer_pcm *dpcm = runtime->private_data;
 295
 296	dpcm->frac_pos = 0;
 297	dpcm->rate = runtime->rate;
 298	dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 299	dpcm->frac_period_size = runtime->period_size * HZ;
 300	dpcm->frac_period_rest = dpcm->frac_period_size;
 301	dpcm->elapsed = 0;
 302
 303	return 0;
 304}
 305
 306static void dummy_systimer_callback(unsigned long data)
 307{
 308	struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 309	unsigned long flags;
 310	int elapsed = 0;
 311	
 312	spin_lock_irqsave(&dpcm->lock, flags);
 313	dummy_systimer_update(dpcm);
 314	dummy_systimer_rearm(dpcm);
 315	elapsed = dpcm->elapsed;
 316	dpcm->elapsed = 0;
 317	spin_unlock_irqrestore(&dpcm->lock, flags);
 318	if (elapsed)
 319		snd_pcm_period_elapsed(dpcm->substream);
 320}
 321
 322static snd_pcm_uframes_t
 323dummy_systimer_pointer(struct snd_pcm_substream *substream)
 324{
 325	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 326	snd_pcm_uframes_t pos;
 327
 328	spin_lock(&dpcm->lock);
 329	dummy_systimer_update(dpcm);
 330	pos = dpcm->frac_pos / HZ;
 331	spin_unlock(&dpcm->lock);
 332	return pos;
 333}
 334
 335static int dummy_systimer_create(struct snd_pcm_substream *substream)
 336{
 337	struct dummy_systimer_pcm *dpcm;
 338
 339	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 340	if (!dpcm)
 341		return -ENOMEM;
 342	substream->runtime->private_data = dpcm;
 343	init_timer(&dpcm->timer);
 344	dpcm->timer.data = (unsigned long) dpcm;
 345	dpcm->timer.function = dummy_systimer_callback;
 346	spin_lock_init(&dpcm->lock);
 347	dpcm->substream = substream;
 348	return 0;
 349}
 350
 351static void dummy_systimer_free(struct snd_pcm_substream *substream)
 352{
 353	kfree(substream->runtime->private_data);
 354}
 355
 356static struct dummy_timer_ops dummy_systimer_ops = {
 357	.create =	dummy_systimer_create,
 358	.free =		dummy_systimer_free,
 359	.prepare =	dummy_systimer_prepare,
 360	.start =	dummy_systimer_start,
 361	.stop =		dummy_systimer_stop,
 362	.pointer =	dummy_systimer_pointer,
 363};
 364
 365#ifdef CONFIG_HIGH_RES_TIMERS
 366/*
 367 * hrtimer interface
 368 */
 369
 370struct dummy_hrtimer_pcm {
 
 
 371	ktime_t base_time;
 372	ktime_t period_time;
 373	atomic_t running;
 374	struct hrtimer timer;
 375	struct tasklet_struct tasklet;
 376	struct snd_pcm_substream *substream;
 377};
 378
 379static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 380{
 381	struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 382	if (atomic_read(&dpcm->running))
 383		snd_pcm_period_elapsed(dpcm->substream);
 384}
 385
 386static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 387{
 388	struct dummy_hrtimer_pcm *dpcm;
 389
 390	dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 391	if (!atomic_read(&dpcm->running))
 392		return HRTIMER_NORESTART;
 393	tasklet_schedule(&dpcm->tasklet);
 
 
 
 
 
 
 
 394	hrtimer_forward_now(timer, dpcm->period_time);
 395	return HRTIMER_RESTART;
 396}
 397
 398static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 399{
 400	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 401
 402	dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 403	hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 404	atomic_set(&dpcm->running, 1);
 405	return 0;
 406}
 407
 408static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 409{
 410	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 411
 412	atomic_set(&dpcm->running, 0);
 413	hrtimer_cancel(&dpcm->timer);
 
 414	return 0;
 415}
 416
 417static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 418{
 419	tasklet_kill(&dpcm->tasklet);
 420}
 421
 422static snd_pcm_uframes_t
 423dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 424{
 425	struct snd_pcm_runtime *runtime = substream->runtime;
 426	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 427	u64 delta;
 428	u32 pos;
 429
 430	delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 431			       dpcm->base_time);
 432	delta = div_u64(delta * runtime->rate + 999999, 1000000);
 433	div_u64_rem(delta, runtime->buffer_size, &pos);
 434	return pos;
 435}
 436
 437static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 438{
 439	struct snd_pcm_runtime *runtime = substream->runtime;
 440	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 441	unsigned int period, rate;
 442	long sec;
 443	unsigned long nsecs;
 444
 445	dummy_hrtimer_sync(dpcm);
 446	period = runtime->period_size;
 447	rate = runtime->rate;
 448	sec = period / rate;
 449	period %= rate;
 450	nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 451	dpcm->period_time = ktime_set(sec, nsecs);
 452
 453	return 0;
 454}
 455
 456static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 457{
 458	struct dummy_hrtimer_pcm *dpcm;
 459
 460	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 461	if (!dpcm)
 462		return -ENOMEM;
 463	substream->runtime->private_data = dpcm;
 464	hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 465	dpcm->timer.function = dummy_hrtimer_callback;
 466	dpcm->substream = substream;
 467	atomic_set(&dpcm->running, 0);
 468	tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 469		     (unsigned long)dpcm);
 470	return 0;
 471}
 472
 473static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 474{
 475	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 476	dummy_hrtimer_sync(dpcm);
 477	kfree(dpcm);
 478}
 479
 480static struct dummy_timer_ops dummy_hrtimer_ops = {
 481	.create =	dummy_hrtimer_create,
 482	.free =		dummy_hrtimer_free,
 483	.prepare =	dummy_hrtimer_prepare,
 484	.start =	dummy_hrtimer_start,
 485	.stop =		dummy_hrtimer_stop,
 486	.pointer =	dummy_hrtimer_pointer,
 487};
 488
 489#endif /* CONFIG_HIGH_RES_TIMERS */
 490
 491/*
 492 * PCM interface
 493 */
 494
 495static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 496{
 497	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 498
 499	switch (cmd) {
 500	case SNDRV_PCM_TRIGGER_START:
 501	case SNDRV_PCM_TRIGGER_RESUME:
 502		return dummy->timer_ops->start(substream);
 503	case SNDRV_PCM_TRIGGER_STOP:
 504	case SNDRV_PCM_TRIGGER_SUSPEND:
 505		return dummy->timer_ops->stop(substream);
 506	}
 507	return -EINVAL;
 508}
 509
 510static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 511{
 512	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 513
 514	return dummy->timer_ops->prepare(substream);
 515}
 516
 517static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 518{
 519	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 520
 521	return dummy->timer_ops->pointer(substream);
 522}
 523
 524static struct snd_pcm_hardware dummy_pcm_hardware = {
 525	.info =			(SNDRV_PCM_INFO_MMAP |
 526				 SNDRV_PCM_INFO_INTERLEAVED |
 527				 SNDRV_PCM_INFO_RESUME |
 528				 SNDRV_PCM_INFO_MMAP_VALID),
 529	.formats =		USE_FORMATS,
 530	.rates =		USE_RATE,
 531	.rate_min =		USE_RATE_MIN,
 532	.rate_max =		USE_RATE_MAX,
 533	.channels_min =		USE_CHANNELS_MIN,
 534	.channels_max =		USE_CHANNELS_MAX,
 535	.buffer_bytes_max =	MAX_BUFFER_SIZE,
 536	.period_bytes_min =	MIN_PERIOD_SIZE,
 537	.period_bytes_max =	MAX_PERIOD_SIZE,
 538	.periods_min =		USE_PERIODS_MIN,
 539	.periods_max =		USE_PERIODS_MAX,
 540	.fifo_size =		0,
 541};
 542
 543static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 544			       struct snd_pcm_hw_params *hw_params)
 545{
 546	if (fake_buffer) {
 547		/* runtime->dma_bytes has to be set manually to allow mmap */
 548		substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 549		return 0;
 550	}
 551	return snd_pcm_lib_malloc_pages(substream,
 552					params_buffer_bytes(hw_params));
 553}
 554
 555static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 556{
 557	if (fake_buffer)
 558		return 0;
 559	return snd_pcm_lib_free_pages(substream);
 560}
 561
 562static int dummy_pcm_open(struct snd_pcm_substream *substream)
 563{
 564	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 565	struct dummy_model *model = dummy->model;
 566	struct snd_pcm_runtime *runtime = substream->runtime;
 
 567	int err;
 568
 569	dummy->timer_ops = &dummy_systimer_ops;
 570#ifdef CONFIG_HIGH_RES_TIMERS
 571	if (hrtimer)
 572		dummy->timer_ops = &dummy_hrtimer_ops;
 573#endif
 574
 575	err = dummy->timer_ops->create(substream);
 576	if (err < 0)
 577		return err;
 
 578
 579	runtime->hw = dummy->pcm_hw;
 580	if (substream->pcm->device & 1) {
 581		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 582		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 583	}
 584	if (substream->pcm->device & 2)
 585		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 586				      SNDRV_PCM_INFO_MMAP_VALID);
 587
 588	if (model == NULL)
 589		return 0;
 590
 591	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 592		if (model->playback_constraints)
 593			err = model->playback_constraints(substream->runtime);
 594	} else {
 595		if (model->capture_constraints)
 596			err = model->capture_constraints(substream->runtime);
 597	}
 598	if (err < 0) {
 599		dummy->timer_ops->free(substream);
 600		return err;
 601	}
 602	return 0;
 603}
 604
 605static int dummy_pcm_close(struct snd_pcm_substream *substream)
 606{
 607	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 608	dummy->timer_ops->free(substream);
 609	return 0;
 610}
 611
 612/*
 613 * dummy buffer handling
 614 */
 615
 616static void *dummy_page[2];
 617
 618static void free_fake_buffer(void)
 619{
 620	if (fake_buffer) {
 621		int i;
 622		for (i = 0; i < 2; i++)
 623			if (dummy_page[i]) {
 624				free_page((unsigned long)dummy_page[i]);
 625				dummy_page[i] = NULL;
 626			}
 627	}
 628}
 629
 630static int alloc_fake_buffer(void)
 631{
 632	int i;
 633
 634	if (!fake_buffer)
 635		return 0;
 636	for (i = 0; i < 2; i++) {
 637		dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 638		if (!dummy_page[i]) {
 639			free_fake_buffer();
 640			return -ENOMEM;
 641		}
 642	}
 643	return 0;
 644}
 645
 646static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 647			  int channel, snd_pcm_uframes_t pos,
 648			  void __user *dst, snd_pcm_uframes_t count)
 649{
 650	return 0; /* do nothing */
 651}
 652
 653static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 654			     int channel, snd_pcm_uframes_t pos,
 655			     snd_pcm_uframes_t count)
 656{
 657	return 0; /* do nothing */
 658}
 659
 660static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 661				   unsigned long offset)
 662{
 663	return virt_to_page(dummy_page[substream->stream]); /* the same page */
 664}
 665
 666static struct snd_pcm_ops dummy_pcm_ops = {
 667	.open =		dummy_pcm_open,
 668	.close =	dummy_pcm_close,
 669	.ioctl =	snd_pcm_lib_ioctl,
 670	.hw_params =	dummy_pcm_hw_params,
 671	.hw_free =	dummy_pcm_hw_free,
 672	.prepare =	dummy_pcm_prepare,
 673	.trigger =	dummy_pcm_trigger,
 674	.pointer =	dummy_pcm_pointer,
 675};
 676
 677static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 678	.open =		dummy_pcm_open,
 679	.close =	dummy_pcm_close,
 680	.ioctl =	snd_pcm_lib_ioctl,
 681	.hw_params =	dummy_pcm_hw_params,
 682	.hw_free =	dummy_pcm_hw_free,
 683	.prepare =	dummy_pcm_prepare,
 684	.trigger =	dummy_pcm_trigger,
 685	.pointer =	dummy_pcm_pointer,
 686	.copy =		dummy_pcm_copy,
 687	.silence =	dummy_pcm_silence,
 688	.page =		dummy_pcm_page,
 689};
 690
 691static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 692			      int substreams)
 693{
 694	struct snd_pcm *pcm;
 695	struct snd_pcm_ops *ops;
 696	int err;
 697
 698	err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 699			       substreams, substreams, &pcm);
 700	if (err < 0)
 701		return err;
 702	dummy->pcm = pcm;
 703	if (fake_buffer)
 704		ops = &dummy_pcm_ops_no_buf;
 705	else
 706		ops = &dummy_pcm_ops;
 707	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 708	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 709	pcm->private_data = dummy;
 710	pcm->info_flags = 0;
 711	strcpy(pcm->name, "Dummy PCM");
 712	if (!fake_buffer) {
 713		snd_pcm_lib_preallocate_pages_for_all(pcm,
 714			SNDRV_DMA_TYPE_CONTINUOUS,
 715			snd_dma_continuous_data(GFP_KERNEL),
 716			0, 64*1024);
 717	}
 718	return 0;
 719}
 720
 721/*
 722 * mixer interface
 723 */
 724
 725#define DUMMY_VOLUME(xname, xindex, addr) \
 726{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 727  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 728  .name = xname, .index = xindex, \
 729  .info = snd_dummy_volume_info, \
 730  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 731  .private_value = addr, \
 732  .tlv = { .p = db_scale_dummy } }
 733
 734static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 735				 struct snd_ctl_elem_info *uinfo)
 736{
 737	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 738	uinfo->count = 2;
 739	uinfo->value.integer.min = -50;
 740	uinfo->value.integer.max = 100;
 741	return 0;
 742}
 743 
 744static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 745				struct snd_ctl_elem_value *ucontrol)
 746{
 747	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 748	int addr = kcontrol->private_value;
 749
 750	spin_lock_irq(&dummy->mixer_lock);
 751	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 752	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 753	spin_unlock_irq(&dummy->mixer_lock);
 754	return 0;
 755}
 756
 757static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 758				struct snd_ctl_elem_value *ucontrol)
 759{
 760	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 761	int change, addr = kcontrol->private_value;
 762	int left, right;
 763
 764	left = ucontrol->value.integer.value[0];
 765	if (left < -50)
 766		left = -50;
 767	if (left > 100)
 768		left = 100;
 769	right = ucontrol->value.integer.value[1];
 770	if (right < -50)
 771		right = -50;
 772	if (right > 100)
 773		right = 100;
 774	spin_lock_irq(&dummy->mixer_lock);
 775	change = dummy->mixer_volume[addr][0] != left ||
 776	         dummy->mixer_volume[addr][1] != right;
 777	dummy->mixer_volume[addr][0] = left;
 778	dummy->mixer_volume[addr][1] = right;
 779	spin_unlock_irq(&dummy->mixer_lock);
 780	return change;
 781}
 782
 783static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 784
 785#define DUMMY_CAPSRC(xname, xindex, addr) \
 786{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 787  .info = snd_dummy_capsrc_info, \
 788  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 789  .private_value = addr }
 790
 791#define snd_dummy_capsrc_info	snd_ctl_boolean_stereo_info
 792 
 793static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 794				struct snd_ctl_elem_value *ucontrol)
 795{
 796	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 797	int addr = kcontrol->private_value;
 798
 799	spin_lock_irq(&dummy->mixer_lock);
 800	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 801	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 802	spin_unlock_irq(&dummy->mixer_lock);
 803	return 0;
 804}
 805
 806static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 807{
 808	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 809	int change, addr = kcontrol->private_value;
 810	int left, right;
 811
 812	left = ucontrol->value.integer.value[0] & 1;
 813	right = ucontrol->value.integer.value[1] & 1;
 814	spin_lock_irq(&dummy->mixer_lock);
 815	change = dummy->capture_source[addr][0] != left &&
 816	         dummy->capture_source[addr][1] != right;
 817	dummy->capture_source[addr][0] = left;
 818	dummy->capture_source[addr][1] = right;
 819	spin_unlock_irq(&dummy->mixer_lock);
 820	return change;
 821}
 822
 823static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
 824				struct snd_ctl_elem_info *info)
 825{
 826	const char *const names[] = { "None", "CD Player" };
 827
 828	return snd_ctl_enum_info(info, 1, 2, names);
 829}
 830
 831static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
 832			       struct snd_ctl_elem_value *value)
 833{
 834	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 835
 836	value->value.enumerated.item[0] = dummy->iobox;
 837	return 0;
 838}
 839
 840static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
 841			       struct snd_ctl_elem_value *value)
 842{
 843	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 844	int changed;
 845
 846	if (value->value.enumerated.item[0] > 1)
 847		return -EINVAL;
 848
 849	changed = value->value.enumerated.item[0] != dummy->iobox;
 850	if (changed) {
 851		dummy->iobox = value->value.enumerated.item[0];
 852
 853		if (dummy->iobox) {
 854			dummy->cd_volume_ctl->vd[0].access &=
 855				~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 856			dummy->cd_switch_ctl->vd[0].access &=
 857				~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 858		} else {
 859			dummy->cd_volume_ctl->vd[0].access |=
 860				SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 861			dummy->cd_switch_ctl->vd[0].access |=
 862				SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 863		}
 864
 865		snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 866			       &dummy->cd_volume_ctl->id);
 867		snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 868			       &dummy->cd_switch_ctl->id);
 869	}
 870
 871	return changed;
 872}
 873
 874static struct snd_kcontrol_new snd_dummy_controls[] = {
 875DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 876DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 877DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 878DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 879DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 880DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 881DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 882DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 883DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 884DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
 885{
 886	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 887	.name  = "External I/O Box",
 888	.info  = snd_dummy_iobox_info,
 889	.get   = snd_dummy_iobox_get,
 890	.put   = snd_dummy_iobox_put,
 891},
 892};
 893
 894static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 895{
 896	struct snd_card *card = dummy->card;
 897	struct snd_kcontrol *kcontrol;
 898	unsigned int idx;
 899	int err;
 900
 901	spin_lock_init(&dummy->mixer_lock);
 902	strcpy(card->mixername, "Dummy Mixer");
 903	dummy->iobox = 1;
 904
 905	for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 906		kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
 907		err = snd_ctl_add(card, kcontrol);
 908		if (err < 0)
 909			return err;
 910		if (!strcmp(kcontrol->id.name, "CD Volume"))
 911			dummy->cd_volume_ctl = kcontrol;
 912		else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
 913			dummy->cd_switch_ctl = kcontrol;
 914
 915	}
 916	return 0;
 917}
 918
 919#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_PROC_FS)
 920/*
 921 * proc interface
 922 */
 923static void print_formats(struct snd_dummy *dummy,
 924			  struct snd_info_buffer *buffer)
 925{
 926	int i;
 927
 928	for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
 929		if (dummy->pcm_hw.formats & (1ULL << i))
 930			snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 931	}
 932}
 933
 934static void print_rates(struct snd_dummy *dummy,
 935			struct snd_info_buffer *buffer)
 936{
 937	static int rates[] = {
 938		5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 939		64000, 88200, 96000, 176400, 192000,
 940	};
 941	int i;
 942
 943	if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 944		snd_iprintf(buffer, " continuous");
 945	if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 946		snd_iprintf(buffer, " knot");
 947	for (i = 0; i < ARRAY_SIZE(rates); i++)
 948		if (dummy->pcm_hw.rates & (1 << i))
 949			snd_iprintf(buffer, " %d", rates[i]);
 950}
 951
 952#define get_dummy_int_ptr(dummy, ofs) \
 953	(unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 954#define get_dummy_ll_ptr(dummy, ofs) \
 955	(unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 956
 957struct dummy_hw_field {
 958	const char *name;
 959	const char *format;
 960	unsigned int offset;
 961	unsigned int size;
 962};
 963#define FIELD_ENTRY(item, fmt) {		   \
 964	.name = #item,				   \
 965	.format = fmt,				   \
 966	.offset = offsetof(struct snd_pcm_hardware, item), \
 967	.size = sizeof(dummy_pcm_hardware.item) }
 968
 969static struct dummy_hw_field fields[] = {
 970	FIELD_ENTRY(formats, "%#llx"),
 971	FIELD_ENTRY(rates, "%#x"),
 972	FIELD_ENTRY(rate_min, "%d"),
 973	FIELD_ENTRY(rate_max, "%d"),
 974	FIELD_ENTRY(channels_min, "%d"),
 975	FIELD_ENTRY(channels_max, "%d"),
 976	FIELD_ENTRY(buffer_bytes_max, "%ld"),
 977	FIELD_ENTRY(period_bytes_min, "%ld"),
 978	FIELD_ENTRY(period_bytes_max, "%ld"),
 979	FIELD_ENTRY(periods_min, "%d"),
 980	FIELD_ENTRY(periods_max, "%d"),
 981};
 982
 983static void dummy_proc_read(struct snd_info_entry *entry,
 984			    struct snd_info_buffer *buffer)
 985{
 986	struct snd_dummy *dummy = entry->private_data;
 987	int i;
 988
 989	for (i = 0; i < ARRAY_SIZE(fields); i++) {
 990		snd_iprintf(buffer, "%s ", fields[i].name);
 991		if (fields[i].size == sizeof(int))
 992			snd_iprintf(buffer, fields[i].format,
 993				*get_dummy_int_ptr(dummy, fields[i].offset));
 994		else
 995			snd_iprintf(buffer, fields[i].format,
 996				*get_dummy_ll_ptr(dummy, fields[i].offset));
 997		if (!strcmp(fields[i].name, "formats"))
 998			print_formats(dummy, buffer);
 999		else if (!strcmp(fields[i].name, "rates"))
1000			print_rates(dummy, buffer);
1001		snd_iprintf(buffer, "\n");
1002	}
1003}
1004
1005static void dummy_proc_write(struct snd_info_entry *entry,
1006			     struct snd_info_buffer *buffer)
1007{
1008	struct snd_dummy *dummy = entry->private_data;
1009	char line[64];
1010
1011	while (!snd_info_get_line(buffer, line, sizeof(line))) {
1012		char item[20];
1013		const char *ptr;
1014		unsigned long long val;
1015		int i;
1016
1017		ptr = snd_info_get_str(item, line, sizeof(item));
1018		for (i = 0; i < ARRAY_SIZE(fields); i++) {
1019			if (!strcmp(item, fields[i].name))
1020				break;
1021		}
1022		if (i >= ARRAY_SIZE(fields))
1023			continue;
1024		snd_info_get_str(item, ptr, sizeof(item));
1025		if (kstrtoull(item, 0, &val))
1026			continue;
1027		if (fields[i].size == sizeof(int))
1028			*get_dummy_int_ptr(dummy, fields[i].offset) = val;
1029		else
1030			*get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1031	}
1032}
1033
1034static void dummy_proc_init(struct snd_dummy *chip)
1035{
1036	struct snd_info_entry *entry;
1037
1038	if (!snd_card_proc_new(chip->card, "dummy_pcm", &entry)) {
1039		snd_info_set_text_ops(entry, chip, dummy_proc_read);
1040		entry->c.text.write = dummy_proc_write;
1041		entry->mode |= S_IWUSR;
1042		entry->private_data = chip;
1043	}
1044}
1045#else
1046#define dummy_proc_init(x)
1047#endif /* CONFIG_SND_DEBUG && CONFIG_PROC_FS */
1048
1049static int snd_dummy_probe(struct platform_device *devptr)
1050{
1051	struct snd_card *card;
1052	struct snd_dummy *dummy;
1053	struct dummy_model *m = NULL, **mdl;
1054	int idx, err;
1055	int dev = devptr->id;
1056
1057	err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1058			   sizeof(struct snd_dummy), &card);
1059	if (err < 0)
1060		return err;
1061	dummy = card->private_data;
1062	dummy->card = card;
1063	for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1064		if (strcmp(model[dev], (*mdl)->name) == 0) {
1065			printk(KERN_INFO
1066				"snd-dummy: Using model '%s' for card %i\n",
1067				(*mdl)->name, card->number);
1068			m = dummy->model = *mdl;
1069			break;
1070		}
1071	}
1072	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1073		if (pcm_substreams[dev] < 1)
1074			pcm_substreams[dev] = 1;
1075		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1076			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1077		err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1078		if (err < 0)
1079			goto __nodev;
1080	}
1081
1082	dummy->pcm_hw = dummy_pcm_hardware;
1083	if (m) {
1084		if (m->formats)
1085			dummy->pcm_hw.formats = m->formats;
1086		if (m->buffer_bytes_max)
1087			dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1088		if (m->period_bytes_min)
1089			dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1090		if (m->period_bytes_max)
1091			dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1092		if (m->periods_min)
1093			dummy->pcm_hw.periods_min = m->periods_min;
1094		if (m->periods_max)
1095			dummy->pcm_hw.periods_max = m->periods_max;
1096		if (m->rates)
1097			dummy->pcm_hw.rates = m->rates;
1098		if (m->rate_min)
1099			dummy->pcm_hw.rate_min = m->rate_min;
1100		if (m->rate_max)
1101			dummy->pcm_hw.rate_max = m->rate_max;
1102		if (m->channels_min)
1103			dummy->pcm_hw.channels_min = m->channels_min;
1104		if (m->channels_max)
1105			dummy->pcm_hw.channels_max = m->channels_max;
1106	}
1107
 
 
 
 
 
 
1108	err = snd_card_dummy_new_mixer(dummy);
1109	if (err < 0)
1110		goto __nodev;
1111	strcpy(card->driver, "Dummy");
1112	strcpy(card->shortname, "Dummy");
1113	sprintf(card->longname, "Dummy %i", dev + 1);
1114
1115	dummy_proc_init(dummy);
1116
1117	err = snd_card_register(card);
1118	if (err == 0) {
1119		platform_set_drvdata(devptr, card);
1120		return 0;
1121	}
1122      __nodev:
1123	snd_card_free(card);
1124	return err;
1125}
1126
1127static int snd_dummy_remove(struct platform_device *devptr)
1128{
1129	snd_card_free(platform_get_drvdata(devptr));
1130	return 0;
1131}
1132
1133#ifdef CONFIG_PM_SLEEP
1134static int snd_dummy_suspend(struct device *pdev)
1135{
1136	struct snd_card *card = dev_get_drvdata(pdev);
1137	struct snd_dummy *dummy = card->private_data;
1138
1139	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1140	snd_pcm_suspend_all(dummy->pcm);
1141	return 0;
1142}
1143	
1144static int snd_dummy_resume(struct device *pdev)
1145{
1146	struct snd_card *card = dev_get_drvdata(pdev);
1147
1148	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1149	return 0;
1150}
1151
1152static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1153#define SND_DUMMY_PM_OPS	&snd_dummy_pm
1154#else
1155#define SND_DUMMY_PM_OPS	NULL
1156#endif
1157
1158#define SND_DUMMY_DRIVER	"snd_dummy"
1159
1160static struct platform_driver snd_dummy_driver = {
1161	.probe		= snd_dummy_probe,
1162	.remove		= snd_dummy_remove,
1163	.driver		= {
1164		.name	= SND_DUMMY_DRIVER,
1165		.owner	= THIS_MODULE,
1166		.pm	= SND_DUMMY_PM_OPS,
1167	},
1168};
1169
1170static void snd_dummy_unregister_all(void)
1171{
1172	int i;
1173
1174	for (i = 0; i < ARRAY_SIZE(devices); ++i)
1175		platform_device_unregister(devices[i]);
1176	platform_driver_unregister(&snd_dummy_driver);
1177	free_fake_buffer();
1178}
1179
1180static int __init alsa_card_dummy_init(void)
1181{
1182	int i, cards, err;
1183
1184	err = platform_driver_register(&snd_dummy_driver);
1185	if (err < 0)
1186		return err;
1187
1188	err = alloc_fake_buffer();
1189	if (err < 0) {
1190		platform_driver_unregister(&snd_dummy_driver);
1191		return err;
1192	}
1193
1194	cards = 0;
1195	for (i = 0; i < SNDRV_CARDS; i++) {
1196		struct platform_device *device;
1197		if (! enable[i])
1198			continue;
1199		device = platform_device_register_simple(SND_DUMMY_DRIVER,
1200							 i, NULL, 0);
1201		if (IS_ERR(device))
1202			continue;
1203		if (!platform_get_drvdata(device)) {
1204			platform_device_unregister(device);
1205			continue;
1206		}
1207		devices[i] = device;
1208		cards++;
1209	}
1210	if (!cards) {
1211#ifdef MODULE
1212		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1213#endif
1214		snd_dummy_unregister_all();
1215		return -ENODEV;
1216	}
1217	return 0;
1218}
1219
1220static void __exit alsa_card_dummy_exit(void)
1221{
1222	snd_dummy_unregister_all();
1223}
1224
1225module_init(alsa_card_dummy_init)
1226module_exit(alsa_card_dummy_exit)
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  Dummy soundcard
   4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   5 */
   6
   7#include <linux/init.h>
   8#include <linux/err.h>
   9#include <linux/platform_device.h>
  10#include <linux/jiffies.h>
  11#include <linux/slab.h>
  12#include <linux/time.h>
  13#include <linux/wait.h>
  14#include <linux/hrtimer.h>
  15#include <linux/math64.h>
  16#include <linux/module.h>
  17#include <sound/core.h>
  18#include <sound/control.h>
  19#include <sound/tlv.h>
  20#include <sound/pcm.h>
  21#include <sound/rawmidi.h>
  22#include <sound/info.h>
  23#include <sound/initval.h>
  24
  25MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  26MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  27MODULE_LICENSE("GPL");
 
  28
  29#define MAX_PCM_DEVICES		4
  30#define MAX_PCM_SUBSTREAMS	128
  31#define MAX_MIDI_DEVICES	2
  32
  33/* defaults */
  34#define MAX_BUFFER_SIZE		(64*1024)
  35#define MIN_PERIOD_SIZE		64
  36#define MAX_PERIOD_SIZE		MAX_BUFFER_SIZE
  37#define USE_FORMATS 		(SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
  38#define USE_RATE		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
  39#define USE_RATE_MIN		5500
  40#define USE_RATE_MAX		48000
  41#define USE_CHANNELS_MIN 	1
  42#define USE_CHANNELS_MAX 	2
  43#define USE_PERIODS_MIN 	1
  44#define USE_PERIODS_MAX 	1024
  45#define USE_MIXER_VOLUME_LEVEL_MIN	-50
  46#define USE_MIXER_VOLUME_LEVEL_MAX	100
  47
  48static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
  49static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
  50static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  51static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  52static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  53static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
  54//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
  55static int mixer_volume_level_min = USE_MIXER_VOLUME_LEVEL_MIN;
  56static int mixer_volume_level_max = USE_MIXER_VOLUME_LEVEL_MAX;
  57#ifdef CONFIG_HIGH_RES_TIMERS
  58static bool hrtimer = 1;
  59#endif
  60static bool fake_buffer = 1;
  61
  62module_param_array(index, int, NULL, 0444);
  63MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  64module_param_array(id, charp, NULL, 0444);
  65MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  66module_param_array(enable, bool, NULL, 0444);
  67MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  68module_param_array(model, charp, NULL, 0444);
  69MODULE_PARM_DESC(model, "Soundcard model.");
  70module_param_array(pcm_devs, int, NULL, 0444);
  71MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  72module_param_array(pcm_substreams, int, NULL, 0444);
  73MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
  74//module_param_array(midi_devs, int, NULL, 0444);
  75//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
  76module_param(mixer_volume_level_min, int, 0444);
  77MODULE_PARM_DESC(mixer_volume_level_min, "Minimum mixer volume level for dummy driver. Default: -50");
  78module_param(mixer_volume_level_max, int, 0444);
  79MODULE_PARM_DESC(mixer_volume_level_max, "Maximum mixer volume level for dummy driver. Default: 100");
  80module_param(fake_buffer, bool, 0444);
  81MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  82#ifdef CONFIG_HIGH_RES_TIMERS
  83module_param(hrtimer, bool, 0644);
  84MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  85#endif
  86
  87static struct platform_device *devices[SNDRV_CARDS];
  88
  89#define MIXER_ADDR_MASTER	0
  90#define MIXER_ADDR_LINE		1
  91#define MIXER_ADDR_MIC		2
  92#define MIXER_ADDR_SYNTH	3
  93#define MIXER_ADDR_CD		4
  94#define MIXER_ADDR_LAST		4
  95
  96struct dummy_timer_ops {
  97	int (*create)(struct snd_pcm_substream *);
  98	void (*free)(struct snd_pcm_substream *);
  99	int (*prepare)(struct snd_pcm_substream *);
 100	int (*start)(struct snd_pcm_substream *);
 101	int (*stop)(struct snd_pcm_substream *);
 102	snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
 103};
 104
 105#define get_dummy_ops(substream) \
 106	(*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
 107
 108struct dummy_model {
 109	const char *name;
 110	int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 111	int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 112	u64 formats;
 113	size_t buffer_bytes_max;
 114	size_t period_bytes_min;
 115	size_t period_bytes_max;
 116	unsigned int periods_min;
 117	unsigned int periods_max;
 118	unsigned int rates;
 119	unsigned int rate_min;
 120	unsigned int rate_max;
 121	unsigned int channels_min;
 122	unsigned int channels_max;
 123};
 124
 125struct snd_dummy {
 126	struct snd_card *card;
 127	const struct dummy_model *model;
 128	struct snd_pcm *pcm;
 129	struct snd_pcm_hardware pcm_hw;
 130	spinlock_t mixer_lock;
 131	int mixer_volume[MIXER_ADDR_LAST+1][2];
 132	int capture_source[MIXER_ADDR_LAST+1][2];
 133	int iobox;
 134	struct snd_kcontrol *cd_volume_ctl;
 135	struct snd_kcontrol *cd_switch_ctl;
 
 136};
 137
 138/*
 139 * card models
 140 */
 141
 142static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 143{
 144	int err;
 145	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 146	if (err < 0)
 147		return err;
 148	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 149	if (err < 0)
 150		return err;
 151	return 0;
 152}
 153
 154static const struct dummy_model model_emu10k1 = {
 155	.name = "emu10k1",
 156	.playback_constraints = emu10k1_playback_constraints,
 157	.buffer_bytes_max = 128 * 1024,
 158};
 159
 160static const struct dummy_model model_rme9652 = {
 161	.name = "rme9652",
 162	.buffer_bytes_max = 26 * 64 * 1024,
 163	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 164	.channels_min = 26,
 165	.channels_max = 26,
 166	.periods_min = 2,
 167	.periods_max = 2,
 168};
 169
 170static const struct dummy_model model_ice1712 = {
 171	.name = "ice1712",
 172	.buffer_bytes_max = 256 * 1024,
 173	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 174	.channels_min = 10,
 175	.channels_max = 10,
 176	.periods_min = 1,
 177	.periods_max = 1024,
 178};
 179
 180static const struct dummy_model model_uda1341 = {
 181	.name = "uda1341",
 182	.buffer_bytes_max = 16380,
 183	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 184	.channels_min = 2,
 185	.channels_max = 2,
 186	.periods_min = 2,
 187	.periods_max = 255,
 188};
 189
 190static const struct dummy_model model_ac97 = {
 191	.name = "ac97",
 192	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 193	.channels_min = 2,
 194	.channels_max = 2,
 195	.rates = SNDRV_PCM_RATE_48000,
 196	.rate_min = 48000,
 197	.rate_max = 48000,
 198};
 199
 200static const struct dummy_model model_ca0106 = {
 201	.name = "ca0106",
 202	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 203	.buffer_bytes_max = ((65536-64)*8),
 204	.period_bytes_max = (65536-64),
 205	.periods_min = 2,
 206	.periods_max = 8,
 207	.channels_min = 2,
 208	.channels_max = 2,
 209	.rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 210	.rate_min = 48000,
 211	.rate_max = 192000,
 212};
 213
 214static const struct dummy_model *dummy_models[] = {
 215	&model_emu10k1,
 216	&model_rme9652,
 217	&model_ice1712,
 218	&model_uda1341,
 219	&model_ac97,
 220	&model_ca0106,
 221	NULL
 222};
 223
 224/*
 225 * system timer interface
 226 */
 227
 228struct dummy_systimer_pcm {
 229	/* ops must be the first item */
 230	const struct dummy_timer_ops *timer_ops;
 231	spinlock_t lock;
 232	struct timer_list timer;
 233	unsigned long base_time;
 234	unsigned int frac_pos;	/* fractional sample position (based HZ) */
 235	unsigned int frac_period_rest;
 236	unsigned int frac_buffer_size;	/* buffer_size * HZ */
 237	unsigned int frac_period_size;	/* period_size * HZ */
 238	unsigned int rate;
 239	int elapsed;
 240	struct snd_pcm_substream *substream;
 241};
 242
 243static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 244{
 245	mod_timer(&dpcm->timer, jiffies +
 246		DIV_ROUND_UP(dpcm->frac_period_rest, dpcm->rate));
 
 247}
 248
 249static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 250{
 251	unsigned long delta;
 252
 253	delta = jiffies - dpcm->base_time;
 254	if (!delta)
 255		return;
 256	dpcm->base_time += delta;
 257	delta *= dpcm->rate;
 258	dpcm->frac_pos += delta;
 259	while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 260		dpcm->frac_pos -= dpcm->frac_buffer_size;
 261	while (dpcm->frac_period_rest <= delta) {
 262		dpcm->elapsed++;
 263		dpcm->frac_period_rest += dpcm->frac_period_size;
 264	}
 265	dpcm->frac_period_rest -= delta;
 266}
 267
 268static int dummy_systimer_start(struct snd_pcm_substream *substream)
 269{
 270	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 271	spin_lock(&dpcm->lock);
 272	dpcm->base_time = jiffies;
 273	dummy_systimer_rearm(dpcm);
 274	spin_unlock(&dpcm->lock);
 275	return 0;
 276}
 277
 278static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 279{
 280	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 281	spin_lock(&dpcm->lock);
 282	del_timer(&dpcm->timer);
 283	spin_unlock(&dpcm->lock);
 284	return 0;
 285}
 286
 287static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 288{
 289	struct snd_pcm_runtime *runtime = substream->runtime;
 290	struct dummy_systimer_pcm *dpcm = runtime->private_data;
 291
 292	dpcm->frac_pos = 0;
 293	dpcm->rate = runtime->rate;
 294	dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 295	dpcm->frac_period_size = runtime->period_size * HZ;
 296	dpcm->frac_period_rest = dpcm->frac_period_size;
 297	dpcm->elapsed = 0;
 298
 299	return 0;
 300}
 301
 302static void dummy_systimer_callback(struct timer_list *t)
 303{
 304	struct dummy_systimer_pcm *dpcm = from_timer(dpcm, t, timer);
 305	unsigned long flags;
 306	int elapsed = 0;
 307
 308	spin_lock_irqsave(&dpcm->lock, flags);
 309	dummy_systimer_update(dpcm);
 310	dummy_systimer_rearm(dpcm);
 311	elapsed = dpcm->elapsed;
 312	dpcm->elapsed = 0;
 313	spin_unlock_irqrestore(&dpcm->lock, flags);
 314	if (elapsed)
 315		snd_pcm_period_elapsed(dpcm->substream);
 316}
 317
 318static snd_pcm_uframes_t
 319dummy_systimer_pointer(struct snd_pcm_substream *substream)
 320{
 321	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 322	snd_pcm_uframes_t pos;
 323
 324	spin_lock(&dpcm->lock);
 325	dummy_systimer_update(dpcm);
 326	pos = dpcm->frac_pos / HZ;
 327	spin_unlock(&dpcm->lock);
 328	return pos;
 329}
 330
 331static int dummy_systimer_create(struct snd_pcm_substream *substream)
 332{
 333	struct dummy_systimer_pcm *dpcm;
 334
 335	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 336	if (!dpcm)
 337		return -ENOMEM;
 338	substream->runtime->private_data = dpcm;
 339	timer_setup(&dpcm->timer, dummy_systimer_callback, 0);
 
 
 340	spin_lock_init(&dpcm->lock);
 341	dpcm->substream = substream;
 342	return 0;
 343}
 344
 345static void dummy_systimer_free(struct snd_pcm_substream *substream)
 346{
 347	kfree(substream->runtime->private_data);
 348}
 349
 350static const struct dummy_timer_ops dummy_systimer_ops = {
 351	.create =	dummy_systimer_create,
 352	.free =		dummy_systimer_free,
 353	.prepare =	dummy_systimer_prepare,
 354	.start =	dummy_systimer_start,
 355	.stop =		dummy_systimer_stop,
 356	.pointer =	dummy_systimer_pointer,
 357};
 358
 359#ifdef CONFIG_HIGH_RES_TIMERS
 360/*
 361 * hrtimer interface
 362 */
 363
 364struct dummy_hrtimer_pcm {
 365	/* ops must be the first item */
 366	const struct dummy_timer_ops *timer_ops;
 367	ktime_t base_time;
 368	ktime_t period_time;
 369	atomic_t running;
 370	struct hrtimer timer;
 
 371	struct snd_pcm_substream *substream;
 372};
 373
 
 
 
 
 
 
 
 374static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 375{
 376	struct dummy_hrtimer_pcm *dpcm;
 377
 378	dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 379	if (!atomic_read(&dpcm->running))
 380		return HRTIMER_NORESTART;
 381	/*
 382	 * In cases of XRUN and draining, this calls .trigger to stop PCM
 383	 * substream.
 384	 */
 385	snd_pcm_period_elapsed(dpcm->substream);
 386	if (!atomic_read(&dpcm->running))
 387		return HRTIMER_NORESTART;
 388
 389	hrtimer_forward_now(timer, dpcm->period_time);
 390	return HRTIMER_RESTART;
 391}
 392
 393static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 394{
 395	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 396
 397	dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 398	hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL_SOFT);
 399	atomic_set(&dpcm->running, 1);
 400	return 0;
 401}
 402
 403static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 404{
 405	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 406
 407	atomic_set(&dpcm->running, 0);
 408	if (!hrtimer_callback_running(&dpcm->timer))
 409		hrtimer_cancel(&dpcm->timer);
 410	return 0;
 411}
 412
 413static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 414{
 415	hrtimer_cancel(&dpcm->timer);
 416}
 417
 418static snd_pcm_uframes_t
 419dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 420{
 421	struct snd_pcm_runtime *runtime = substream->runtime;
 422	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 423	u64 delta;
 424	u32 pos;
 425
 426	delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 427			       dpcm->base_time);
 428	delta = div_u64(delta * runtime->rate + 999999, 1000000);
 429	div_u64_rem(delta, runtime->buffer_size, &pos);
 430	return pos;
 431}
 432
 433static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 434{
 435	struct snd_pcm_runtime *runtime = substream->runtime;
 436	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 437	unsigned int period, rate;
 438	long sec;
 439	unsigned long nsecs;
 440
 441	dummy_hrtimer_sync(dpcm);
 442	period = runtime->period_size;
 443	rate = runtime->rate;
 444	sec = period / rate;
 445	period %= rate;
 446	nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 447	dpcm->period_time = ktime_set(sec, nsecs);
 448
 449	return 0;
 450}
 451
 452static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 453{
 454	struct dummy_hrtimer_pcm *dpcm;
 455
 456	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 457	if (!dpcm)
 458		return -ENOMEM;
 459	substream->runtime->private_data = dpcm;
 460	hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 461	dpcm->timer.function = dummy_hrtimer_callback;
 462	dpcm->substream = substream;
 463	atomic_set(&dpcm->running, 0);
 
 
 464	return 0;
 465}
 466
 467static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 468{
 469	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 470	dummy_hrtimer_sync(dpcm);
 471	kfree(dpcm);
 472}
 473
 474static const struct dummy_timer_ops dummy_hrtimer_ops = {
 475	.create =	dummy_hrtimer_create,
 476	.free =		dummy_hrtimer_free,
 477	.prepare =	dummy_hrtimer_prepare,
 478	.start =	dummy_hrtimer_start,
 479	.stop =		dummy_hrtimer_stop,
 480	.pointer =	dummy_hrtimer_pointer,
 481};
 482
 483#endif /* CONFIG_HIGH_RES_TIMERS */
 484
 485/*
 486 * PCM interface
 487 */
 488
 489static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 490{
 
 
 491	switch (cmd) {
 492	case SNDRV_PCM_TRIGGER_START:
 493	case SNDRV_PCM_TRIGGER_RESUME:
 494		return get_dummy_ops(substream)->start(substream);
 495	case SNDRV_PCM_TRIGGER_STOP:
 496	case SNDRV_PCM_TRIGGER_SUSPEND:
 497		return get_dummy_ops(substream)->stop(substream);
 498	}
 499	return -EINVAL;
 500}
 501
 502static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 503{
 504	return get_dummy_ops(substream)->prepare(substream);
 
 
 505}
 506
 507static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 508{
 509	return get_dummy_ops(substream)->pointer(substream);
 
 
 510}
 511
 512static const struct snd_pcm_hardware dummy_pcm_hardware = {
 513	.info =			(SNDRV_PCM_INFO_MMAP |
 514				 SNDRV_PCM_INFO_INTERLEAVED |
 515				 SNDRV_PCM_INFO_RESUME |
 516				 SNDRV_PCM_INFO_MMAP_VALID),
 517	.formats =		USE_FORMATS,
 518	.rates =		USE_RATE,
 519	.rate_min =		USE_RATE_MIN,
 520	.rate_max =		USE_RATE_MAX,
 521	.channels_min =		USE_CHANNELS_MIN,
 522	.channels_max =		USE_CHANNELS_MAX,
 523	.buffer_bytes_max =	MAX_BUFFER_SIZE,
 524	.period_bytes_min =	MIN_PERIOD_SIZE,
 525	.period_bytes_max =	MAX_PERIOD_SIZE,
 526	.periods_min =		USE_PERIODS_MIN,
 527	.periods_max =		USE_PERIODS_MAX,
 528	.fifo_size =		0,
 529};
 530
 531static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 532			       struct snd_pcm_hw_params *hw_params)
 533{
 534	if (fake_buffer) {
 535		/* runtime->dma_bytes has to be set manually to allow mmap */
 536		substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 537		return 0;
 538	}
 539	return 0;
 
 
 
 
 
 
 
 
 540}
 541
 542static int dummy_pcm_open(struct snd_pcm_substream *substream)
 543{
 544	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 545	const struct dummy_model *model = dummy->model;
 546	struct snd_pcm_runtime *runtime = substream->runtime;
 547	const struct dummy_timer_ops *ops;
 548	int err;
 549
 550	ops = &dummy_systimer_ops;
 551#ifdef CONFIG_HIGH_RES_TIMERS
 552	if (hrtimer)
 553		ops = &dummy_hrtimer_ops;
 554#endif
 555
 556	err = ops->create(substream);
 557	if (err < 0)
 558		return err;
 559	get_dummy_ops(substream) = ops;
 560
 561	runtime->hw = dummy->pcm_hw;
 562	if (substream->pcm->device & 1) {
 563		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 564		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 565	}
 566	if (substream->pcm->device & 2)
 567		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 568				      SNDRV_PCM_INFO_MMAP_VALID);
 569
 570	if (model == NULL)
 571		return 0;
 572
 573	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 574		if (model->playback_constraints)
 575			err = model->playback_constraints(substream->runtime);
 576	} else {
 577		if (model->capture_constraints)
 578			err = model->capture_constraints(substream->runtime);
 579	}
 580	if (err < 0) {
 581		get_dummy_ops(substream)->free(substream);
 582		return err;
 583	}
 584	return 0;
 585}
 586
 587static int dummy_pcm_close(struct snd_pcm_substream *substream)
 588{
 589	get_dummy_ops(substream)->free(substream);
 
 590	return 0;
 591}
 592
 593/*
 594 * dummy buffer handling
 595 */
 596
 597static void *dummy_page[2];
 598
 599static void free_fake_buffer(void)
 600{
 601	if (fake_buffer) {
 602		int i;
 603		for (i = 0; i < 2; i++)
 604			if (dummy_page[i]) {
 605				free_page((unsigned long)dummy_page[i]);
 606				dummy_page[i] = NULL;
 607			}
 608	}
 609}
 610
 611static int alloc_fake_buffer(void)
 612{
 613	int i;
 614
 615	if (!fake_buffer)
 616		return 0;
 617	for (i = 0; i < 2; i++) {
 618		dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 619		if (!dummy_page[i]) {
 620			free_fake_buffer();
 621			return -ENOMEM;
 622		}
 623	}
 624	return 0;
 625}
 626
 627static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 628			  int channel, unsigned long pos,
 629			  struct iov_iter *iter, unsigned long bytes)
 630{
 631	return 0; /* do nothing */
 632}
 633
 634static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 635			     int channel, unsigned long pos,
 636			     unsigned long bytes)
 637{
 638	return 0; /* do nothing */
 639}
 640
 641static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 642				   unsigned long offset)
 643{
 644	return virt_to_page(dummy_page[substream->stream]); /* the same page */
 645}
 646
 647static const struct snd_pcm_ops dummy_pcm_ops = {
 648	.open =		dummy_pcm_open,
 649	.close =	dummy_pcm_close,
 
 650	.hw_params =	dummy_pcm_hw_params,
 
 651	.prepare =	dummy_pcm_prepare,
 652	.trigger =	dummy_pcm_trigger,
 653	.pointer =	dummy_pcm_pointer,
 654};
 655
 656static const struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 657	.open =		dummy_pcm_open,
 658	.close =	dummy_pcm_close,
 
 659	.hw_params =	dummy_pcm_hw_params,
 
 660	.prepare =	dummy_pcm_prepare,
 661	.trigger =	dummy_pcm_trigger,
 662	.pointer =	dummy_pcm_pointer,
 663	.copy =		dummy_pcm_copy,
 664	.fill_silence =	dummy_pcm_silence,
 665	.page =		dummy_pcm_page,
 666};
 667
 668static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 669			      int substreams)
 670{
 671	struct snd_pcm *pcm;
 672	const struct snd_pcm_ops *ops;
 673	int err;
 674
 675	err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 676			       substreams, substreams, &pcm);
 677	if (err < 0)
 678		return err;
 679	dummy->pcm = pcm;
 680	if (fake_buffer)
 681		ops = &dummy_pcm_ops_no_buf;
 682	else
 683		ops = &dummy_pcm_ops;
 684	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 685	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 686	pcm->private_data = dummy;
 687	pcm->info_flags = 0;
 688	strcpy(pcm->name, "Dummy PCM");
 689	if (!fake_buffer) {
 690		snd_pcm_set_managed_buffer_all(pcm,
 691			SNDRV_DMA_TYPE_CONTINUOUS,
 692			NULL,
 693			0, 64*1024);
 694	}
 695	return 0;
 696}
 697
 698/*
 699 * mixer interface
 700 */
 701
 702#define DUMMY_VOLUME(xname, xindex, addr) \
 703{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 704  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 705  .name = xname, .index = xindex, \
 706  .info = snd_dummy_volume_info, \
 707  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 708  .private_value = addr, \
 709  .tlv = { .p = db_scale_dummy } }
 710
 711static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 712				 struct snd_ctl_elem_info *uinfo)
 713{
 714	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 715	uinfo->count = 2;
 716	uinfo->value.integer.min = mixer_volume_level_min;
 717	uinfo->value.integer.max = mixer_volume_level_max;
 718	return 0;
 719}
 720
 721static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 722				struct snd_ctl_elem_value *ucontrol)
 723{
 724	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 725	int addr = kcontrol->private_value;
 726
 727	spin_lock_irq(&dummy->mixer_lock);
 728	ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 729	ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 730	spin_unlock_irq(&dummy->mixer_lock);
 731	return 0;
 732}
 733
 734static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 735				struct snd_ctl_elem_value *ucontrol)
 736{
 737	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 738	int change, addr = kcontrol->private_value;
 739	int left, right;
 740
 741	left = ucontrol->value.integer.value[0];
 742	if (left < mixer_volume_level_min)
 743		left = mixer_volume_level_min;
 744	if (left > mixer_volume_level_max)
 745		left = mixer_volume_level_max;
 746	right = ucontrol->value.integer.value[1];
 747	if (right < mixer_volume_level_min)
 748		right = mixer_volume_level_min;
 749	if (right > mixer_volume_level_max)
 750		right = mixer_volume_level_max;
 751	spin_lock_irq(&dummy->mixer_lock);
 752	change = dummy->mixer_volume[addr][0] != left ||
 753	         dummy->mixer_volume[addr][1] != right;
 754	dummy->mixer_volume[addr][0] = left;
 755	dummy->mixer_volume[addr][1] = right;
 756	spin_unlock_irq(&dummy->mixer_lock);
 757	return change;
 758}
 759
 760static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 761
 762#define DUMMY_CAPSRC(xname, xindex, addr) \
 763{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 764  .info = snd_dummy_capsrc_info, \
 765  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 766  .private_value = addr }
 767
 768#define snd_dummy_capsrc_info	snd_ctl_boolean_stereo_info
 769
 770static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 771				struct snd_ctl_elem_value *ucontrol)
 772{
 773	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 774	int addr = kcontrol->private_value;
 775
 776	spin_lock_irq(&dummy->mixer_lock);
 777	ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 778	ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 779	spin_unlock_irq(&dummy->mixer_lock);
 780	return 0;
 781}
 782
 783static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 784{
 785	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 786	int change, addr = kcontrol->private_value;
 787	int left, right;
 788
 789	left = ucontrol->value.integer.value[0] & 1;
 790	right = ucontrol->value.integer.value[1] & 1;
 791	spin_lock_irq(&dummy->mixer_lock);
 792	change = dummy->capture_source[addr][0] != left &&
 793	         dummy->capture_source[addr][1] != right;
 794	dummy->capture_source[addr][0] = left;
 795	dummy->capture_source[addr][1] = right;
 796	spin_unlock_irq(&dummy->mixer_lock);
 797	return change;
 798}
 799
 800static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
 801				struct snd_ctl_elem_info *info)
 802{
 803	static const char *const names[] = { "None", "CD Player" };
 804
 805	return snd_ctl_enum_info(info, 1, 2, names);
 806}
 807
 808static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
 809			       struct snd_ctl_elem_value *value)
 810{
 811	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 812
 813	value->value.enumerated.item[0] = dummy->iobox;
 814	return 0;
 815}
 816
 817static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
 818			       struct snd_ctl_elem_value *value)
 819{
 820	struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 821	int changed;
 822
 823	if (value->value.enumerated.item[0] > 1)
 824		return -EINVAL;
 825
 826	changed = value->value.enumerated.item[0] != dummy->iobox;
 827	if (changed) {
 828		dummy->iobox = value->value.enumerated.item[0];
 829
 830		if (dummy->iobox) {
 831			dummy->cd_volume_ctl->vd[0].access &=
 832				~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 833			dummy->cd_switch_ctl->vd[0].access &=
 834				~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 835		} else {
 836			dummy->cd_volume_ctl->vd[0].access |=
 837				SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 838			dummy->cd_switch_ctl->vd[0].access |=
 839				SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 840		}
 841
 842		snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 843			       &dummy->cd_volume_ctl->id);
 844		snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 845			       &dummy->cd_switch_ctl->id);
 846	}
 847
 848	return changed;
 849}
 850
 851static const struct snd_kcontrol_new snd_dummy_controls[] = {
 852DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 853DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 854DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 855DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 856DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 857DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 858DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 859DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 860DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 861DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
 862{
 863	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 864	.name  = "External I/O Box",
 865	.info  = snd_dummy_iobox_info,
 866	.get   = snd_dummy_iobox_get,
 867	.put   = snd_dummy_iobox_put,
 868},
 869};
 870
 871static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 872{
 873	struct snd_card *card = dummy->card;
 874	struct snd_kcontrol *kcontrol;
 875	unsigned int idx;
 876	int err;
 877
 878	spin_lock_init(&dummy->mixer_lock);
 879	strcpy(card->mixername, "Dummy Mixer");
 880	dummy->iobox = 1;
 881
 882	for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 883		kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
 884		err = snd_ctl_add(card, kcontrol);
 885		if (err < 0)
 886			return err;
 887		if (!strcmp(kcontrol->id.name, "CD Volume"))
 888			dummy->cd_volume_ctl = kcontrol;
 889		else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
 890			dummy->cd_switch_ctl = kcontrol;
 891
 892	}
 893	return 0;
 894}
 895
 896#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_PROC_FS)
 897/*
 898 * proc interface
 899 */
 900static void print_formats(struct snd_dummy *dummy,
 901			  struct snd_info_buffer *buffer)
 902{
 903	snd_pcm_format_t i;
 904
 905	pcm_for_each_format(i) {
 906		if (dummy->pcm_hw.formats & pcm_format_to_bits(i))
 907			snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 908	}
 909}
 910
 911static void print_rates(struct snd_dummy *dummy,
 912			struct snd_info_buffer *buffer)
 913{
 914	static const int rates[] = {
 915		5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 916		64000, 88200, 96000, 176400, 192000,
 917	};
 918	int i;
 919
 920	if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 921		snd_iprintf(buffer, " continuous");
 922	if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 923		snd_iprintf(buffer, " knot");
 924	for (i = 0; i < ARRAY_SIZE(rates); i++)
 925		if (dummy->pcm_hw.rates & (1 << i))
 926			snd_iprintf(buffer, " %d", rates[i]);
 927}
 928
 929#define get_dummy_int_ptr(dummy, ofs) \
 930	(unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 931#define get_dummy_ll_ptr(dummy, ofs) \
 932	(unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 933
 934struct dummy_hw_field {
 935	const char *name;
 936	const char *format;
 937	unsigned int offset;
 938	unsigned int size;
 939};
 940#define FIELD_ENTRY(item, fmt) {		   \
 941	.name = #item,				   \
 942	.format = fmt,				   \
 943	.offset = offsetof(struct snd_pcm_hardware, item), \
 944	.size = sizeof(dummy_pcm_hardware.item) }
 945
 946static const struct dummy_hw_field fields[] = {
 947	FIELD_ENTRY(formats, "%#llx"),
 948	FIELD_ENTRY(rates, "%#x"),
 949	FIELD_ENTRY(rate_min, "%d"),
 950	FIELD_ENTRY(rate_max, "%d"),
 951	FIELD_ENTRY(channels_min, "%d"),
 952	FIELD_ENTRY(channels_max, "%d"),
 953	FIELD_ENTRY(buffer_bytes_max, "%ld"),
 954	FIELD_ENTRY(period_bytes_min, "%ld"),
 955	FIELD_ENTRY(period_bytes_max, "%ld"),
 956	FIELD_ENTRY(periods_min, "%d"),
 957	FIELD_ENTRY(periods_max, "%d"),
 958};
 959
 960static void dummy_proc_read(struct snd_info_entry *entry,
 961			    struct snd_info_buffer *buffer)
 962{
 963	struct snd_dummy *dummy = entry->private_data;
 964	int i;
 965
 966	for (i = 0; i < ARRAY_SIZE(fields); i++) {
 967		snd_iprintf(buffer, "%s ", fields[i].name);
 968		if (fields[i].size == sizeof(int))
 969			snd_iprintf(buffer, fields[i].format,
 970				*get_dummy_int_ptr(dummy, fields[i].offset));
 971		else
 972			snd_iprintf(buffer, fields[i].format,
 973				*get_dummy_ll_ptr(dummy, fields[i].offset));
 974		if (!strcmp(fields[i].name, "formats"))
 975			print_formats(dummy, buffer);
 976		else if (!strcmp(fields[i].name, "rates"))
 977			print_rates(dummy, buffer);
 978		snd_iprintf(buffer, "\n");
 979	}
 980}
 981
 982static void dummy_proc_write(struct snd_info_entry *entry,
 983			     struct snd_info_buffer *buffer)
 984{
 985	struct snd_dummy *dummy = entry->private_data;
 986	char line[64];
 987
 988	while (!snd_info_get_line(buffer, line, sizeof(line))) {
 989		char item[20];
 990		const char *ptr;
 991		unsigned long long val;
 992		int i;
 993
 994		ptr = snd_info_get_str(item, line, sizeof(item));
 995		for (i = 0; i < ARRAY_SIZE(fields); i++) {
 996			if (!strcmp(item, fields[i].name))
 997				break;
 998		}
 999		if (i >= ARRAY_SIZE(fields))
1000			continue;
1001		snd_info_get_str(item, ptr, sizeof(item));
1002		if (kstrtoull(item, 0, &val))
1003			continue;
1004		if (fields[i].size == sizeof(int))
1005			*get_dummy_int_ptr(dummy, fields[i].offset) = val;
1006		else
1007			*get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1008	}
1009}
1010
1011static void dummy_proc_init(struct snd_dummy *chip)
1012{
1013	snd_card_rw_proc_new(chip->card, "dummy_pcm", chip,
1014			     dummy_proc_read, dummy_proc_write);
 
 
 
 
 
 
1015}
1016#else
1017#define dummy_proc_init(x)
1018#endif /* CONFIG_SND_DEBUG && CONFIG_SND_PROC_FS */
1019
1020static int snd_dummy_probe(struct platform_device *devptr)
1021{
1022	struct snd_card *card;
1023	struct snd_dummy *dummy;
1024	const struct dummy_model *m = NULL, **mdl;
1025	int idx, err;
1026	int dev = devptr->id;
1027
1028	err = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1029				sizeof(struct snd_dummy), &card);
1030	if (err < 0)
1031		return err;
1032	dummy = card->private_data;
1033	dummy->card = card;
1034	for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1035		if (strcmp(model[dev], (*mdl)->name) == 0) {
1036			pr_info("snd-dummy: Using model '%s' for card %i\n",
 
1037				(*mdl)->name, card->number);
1038			m = dummy->model = *mdl;
1039			break;
1040		}
1041	}
1042	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1043		if (pcm_substreams[dev] < 1)
1044			pcm_substreams[dev] = 1;
1045		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1046			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1047		err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1048		if (err < 0)
1049			return err;
1050	}
1051
1052	dummy->pcm_hw = dummy_pcm_hardware;
1053	if (m) {
1054		if (m->formats)
1055			dummy->pcm_hw.formats = m->formats;
1056		if (m->buffer_bytes_max)
1057			dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1058		if (m->period_bytes_min)
1059			dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1060		if (m->period_bytes_max)
1061			dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1062		if (m->periods_min)
1063			dummy->pcm_hw.periods_min = m->periods_min;
1064		if (m->periods_max)
1065			dummy->pcm_hw.periods_max = m->periods_max;
1066		if (m->rates)
1067			dummy->pcm_hw.rates = m->rates;
1068		if (m->rate_min)
1069			dummy->pcm_hw.rate_min = m->rate_min;
1070		if (m->rate_max)
1071			dummy->pcm_hw.rate_max = m->rate_max;
1072		if (m->channels_min)
1073			dummy->pcm_hw.channels_min = m->channels_min;
1074		if (m->channels_max)
1075			dummy->pcm_hw.channels_max = m->channels_max;
1076	}
1077
1078	if (mixer_volume_level_min > mixer_volume_level_max) {
1079		pr_warn("snd-dummy: Invalid mixer volume level: min=%d, max=%d. Fall back to default value.\n",
1080		mixer_volume_level_min, mixer_volume_level_max);
1081		mixer_volume_level_min = USE_MIXER_VOLUME_LEVEL_MIN;
1082		mixer_volume_level_max = USE_MIXER_VOLUME_LEVEL_MAX;
1083	}
1084	err = snd_card_dummy_new_mixer(dummy);
1085	if (err < 0)
1086		return err;
1087	strcpy(card->driver, "Dummy");
1088	strcpy(card->shortname, "Dummy");
1089	sprintf(card->longname, "Dummy %i", dev + 1);
1090
1091	dummy_proc_init(dummy);
1092
1093	err = snd_card_register(card);
1094	if (err < 0)
1095		return err;
1096	platform_set_drvdata(devptr, card);
 
 
 
 
 
 
 
 
 
1097	return 0;
1098}
1099
 
1100static int snd_dummy_suspend(struct device *pdev)
1101{
1102	struct snd_card *card = dev_get_drvdata(pdev);
 
1103
1104	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 
1105	return 0;
1106}
1107
1108static int snd_dummy_resume(struct device *pdev)
1109{
1110	struct snd_card *card = dev_get_drvdata(pdev);
1111
1112	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1113	return 0;
1114}
1115
1116static DEFINE_SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
 
 
 
 
1117
1118#define SND_DUMMY_DRIVER	"snd_dummy"
1119
1120static struct platform_driver snd_dummy_driver = {
1121	.probe		= snd_dummy_probe,
 
1122	.driver		= {
1123		.name	= SND_DUMMY_DRIVER,
1124		.pm	= &snd_dummy_pm,
 
1125	},
1126};
1127
1128static void snd_dummy_unregister_all(void)
1129{
1130	int i;
1131
1132	for (i = 0; i < ARRAY_SIZE(devices); ++i)
1133		platform_device_unregister(devices[i]);
1134	platform_driver_unregister(&snd_dummy_driver);
1135	free_fake_buffer();
1136}
1137
1138static int __init alsa_card_dummy_init(void)
1139{
1140	int i, cards, err;
1141
1142	err = platform_driver_register(&snd_dummy_driver);
1143	if (err < 0)
1144		return err;
1145
1146	err = alloc_fake_buffer();
1147	if (err < 0) {
1148		platform_driver_unregister(&snd_dummy_driver);
1149		return err;
1150	}
1151
1152	cards = 0;
1153	for (i = 0; i < SNDRV_CARDS; i++) {
1154		struct platform_device *device;
1155		if (! enable[i])
1156			continue;
1157		device = platform_device_register_simple(SND_DUMMY_DRIVER,
1158							 i, NULL, 0);
1159		if (IS_ERR(device))
1160			continue;
1161		if (!platform_get_drvdata(device)) {
1162			platform_device_unregister(device);
1163			continue;
1164		}
1165		devices[i] = device;
1166		cards++;
1167	}
1168	if (!cards) {
1169#ifdef MODULE
1170		pr_err("Dummy soundcard not found or device busy\n");
1171#endif
1172		snd_dummy_unregister_all();
1173		return -ENODEV;
1174	}
1175	return 0;
1176}
1177
1178static void __exit alsa_card_dummy_exit(void)
1179{
1180	snd_dummy_unregister_all();
1181}
1182
1183module_init(alsa_card_dummy_init)
1184module_exit(alsa_card_dummy_exit)