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v5.14.15
   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
  46static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
  47static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
  48static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  49static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  50static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  51static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
  52//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
  53#ifdef CONFIG_HIGH_RES_TIMERS
  54static bool hrtimer = 1;
  55#endif
  56static bool fake_buffer = 1;
  57
  58module_param_array(index, int, NULL, 0444);
  59MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  60module_param_array(id, charp, NULL, 0444);
  61MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  62module_param_array(enable, bool, NULL, 0444);
  63MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  64module_param_array(model, charp, NULL, 0444);
  65MODULE_PARM_DESC(model, "Soundcard model.");
  66module_param_array(pcm_devs, int, NULL, 0444);
  67MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  68module_param_array(pcm_substreams, int, NULL, 0444);
  69MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
  70//module_param_array(midi_devs, int, NULL, 0444);
  71//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
  72module_param(fake_buffer, bool, 0444);
  73MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  74#ifdef CONFIG_HIGH_RES_TIMERS
  75module_param(hrtimer, bool, 0644);
  76MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  77#endif
  78
  79static struct platform_device *devices[SNDRV_CARDS];
  80
  81#define MIXER_ADDR_MASTER	0
  82#define MIXER_ADDR_LINE		1
  83#define MIXER_ADDR_MIC		2
  84#define MIXER_ADDR_SYNTH	3
  85#define MIXER_ADDR_CD		4
  86#define MIXER_ADDR_LAST		4
  87
  88struct dummy_timer_ops {
  89	int (*create)(struct snd_pcm_substream *);
  90	void (*free)(struct snd_pcm_substream *);
  91	int (*prepare)(struct snd_pcm_substream *);
  92	int (*start)(struct snd_pcm_substream *);
  93	int (*stop)(struct snd_pcm_substream *);
  94	snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
  95};
  96
  97#define get_dummy_ops(substream) \
  98	(*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
  99
 100struct dummy_model {
 101	const char *name;
 102	int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 103	int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 104	u64 formats;
 105	size_t buffer_bytes_max;
 106	size_t period_bytes_min;
 107	size_t period_bytes_max;
 108	unsigned int periods_min;
 109	unsigned int periods_max;
 110	unsigned int rates;
 111	unsigned int rate_min;
 112	unsigned int rate_max;
 113	unsigned int channels_min;
 114	unsigned int channels_max;
 115};
 116
 117struct snd_dummy {
 118	struct snd_card *card;
 119	const struct dummy_model *model;
 120	struct snd_pcm *pcm;
 121	struct snd_pcm_hardware pcm_hw;
 122	spinlock_t mixer_lock;
 123	int mixer_volume[MIXER_ADDR_LAST+1][2];
 124	int capture_source[MIXER_ADDR_LAST+1][2];
 125	int iobox;
 126	struct snd_kcontrol *cd_volume_ctl;
 127	struct snd_kcontrol *cd_switch_ctl;
 128};
 129
 130/*
 131 * card models
 132 */
 133
 134static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 135{
 136	int err;
 137	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 138	if (err < 0)
 139		return err;
 140	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 141	if (err < 0)
 142		return err;
 143	return 0;
 144}
 145
 146static const struct dummy_model model_emu10k1 = {
 147	.name = "emu10k1",
 148	.playback_constraints = emu10k1_playback_constraints,
 149	.buffer_bytes_max = 128 * 1024,
 150};
 151
 152static const struct dummy_model model_rme9652 = {
 153	.name = "rme9652",
 154	.buffer_bytes_max = 26 * 64 * 1024,
 155	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 156	.channels_min = 26,
 157	.channels_max = 26,
 158	.periods_min = 2,
 159	.periods_max = 2,
 160};
 161
 162static const struct dummy_model model_ice1712 = {
 163	.name = "ice1712",
 164	.buffer_bytes_max = 256 * 1024,
 165	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 166	.channels_min = 10,
 167	.channels_max = 10,
 168	.periods_min = 1,
 169	.periods_max = 1024,
 170};
 171
 172static const struct dummy_model model_uda1341 = {
 173	.name = "uda1341",
 174	.buffer_bytes_max = 16380,
 175	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 176	.channels_min = 2,
 177	.channels_max = 2,
 178	.periods_min = 2,
 179	.periods_max = 255,
 180};
 181
 182static const struct dummy_model model_ac97 = {
 183	.name = "ac97",
 184	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 185	.channels_min = 2,
 186	.channels_max = 2,
 187	.rates = SNDRV_PCM_RATE_48000,
 188	.rate_min = 48000,
 189	.rate_max = 48000,
 190};
 191
 192static const struct dummy_model model_ca0106 = {
 193	.name = "ca0106",
 194	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 195	.buffer_bytes_max = ((65536-64)*8),
 196	.period_bytes_max = (65536-64),
 197	.periods_min = 2,
 198	.periods_max = 8,
 199	.channels_min = 2,
 200	.channels_max = 2,
 201	.rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 202	.rate_min = 48000,
 203	.rate_max = 192000,
 204};
 205
 206static const struct dummy_model *dummy_models[] = {
 207	&model_emu10k1,
 208	&model_rme9652,
 209	&model_ice1712,
 210	&model_uda1341,
 211	&model_ac97,
 212	&model_ca0106,
 213	NULL
 214};
 215
 216/*
 217 * system timer interface
 218 */
 219
 220struct dummy_systimer_pcm {
 221	/* ops must be the first item */
 222	const struct dummy_timer_ops *timer_ops;
 223	spinlock_t lock;
 224	struct timer_list timer;
 225	unsigned long base_time;
 226	unsigned int frac_pos;	/* fractional sample position (based HZ) */
 227	unsigned int frac_period_rest;
 228	unsigned int frac_buffer_size;	/* buffer_size * HZ */
 229	unsigned int frac_period_size;	/* period_size * HZ */
 230	unsigned int rate;
 231	int elapsed;
 232	struct snd_pcm_substream *substream;
 233};
 234
 235static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 236{
 237	mod_timer(&dpcm->timer, jiffies +
 238		DIV_ROUND_UP(dpcm->frac_period_rest, dpcm->rate));
 239}
 240
 241static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 242{
 243	unsigned long delta;
 244
 245	delta = jiffies - dpcm->base_time;
 246	if (!delta)
 247		return;
 248	dpcm->base_time += delta;
 249	delta *= dpcm->rate;
 250	dpcm->frac_pos += delta;
 251	while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 252		dpcm->frac_pos -= dpcm->frac_buffer_size;
 253	while (dpcm->frac_period_rest <= delta) {
 254		dpcm->elapsed++;
 255		dpcm->frac_period_rest += dpcm->frac_period_size;
 256	}
 257	dpcm->frac_period_rest -= delta;
 258}
 259
 260static int dummy_systimer_start(struct snd_pcm_substream *substream)
 261{
 262	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 263	spin_lock(&dpcm->lock);
 264	dpcm->base_time = jiffies;
 265	dummy_systimer_rearm(dpcm);
 266	spin_unlock(&dpcm->lock);
 267	return 0;
 268}
 269
 270static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 271{
 272	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 273	spin_lock(&dpcm->lock);
 274	del_timer(&dpcm->timer);
 275	spin_unlock(&dpcm->lock);
 276	return 0;
 277}
 278
 279static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 280{
 281	struct snd_pcm_runtime *runtime = substream->runtime;
 282	struct dummy_systimer_pcm *dpcm = runtime->private_data;
 283
 284	dpcm->frac_pos = 0;
 285	dpcm->rate = runtime->rate;
 286	dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 287	dpcm->frac_period_size = runtime->period_size * HZ;
 288	dpcm->frac_period_rest = dpcm->frac_period_size;
 289	dpcm->elapsed = 0;
 290
 291	return 0;
 292}
 293
 294static void dummy_systimer_callback(struct timer_list *t)
 295{
 296	struct dummy_systimer_pcm *dpcm = from_timer(dpcm, t, timer);
 297	unsigned long flags;
 298	int elapsed = 0;
 299	
 300	spin_lock_irqsave(&dpcm->lock, flags);
 301	dummy_systimer_update(dpcm);
 302	dummy_systimer_rearm(dpcm);
 303	elapsed = dpcm->elapsed;
 304	dpcm->elapsed = 0;
 305	spin_unlock_irqrestore(&dpcm->lock, flags);
 306	if (elapsed)
 307		snd_pcm_period_elapsed(dpcm->substream);
 308}
 309
 310static snd_pcm_uframes_t
 311dummy_systimer_pointer(struct snd_pcm_substream *substream)
 312{
 313	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 314	snd_pcm_uframes_t pos;
 315
 316	spin_lock(&dpcm->lock);
 317	dummy_systimer_update(dpcm);
 318	pos = dpcm->frac_pos / HZ;
 319	spin_unlock(&dpcm->lock);
 320	return pos;
 321}
 322
 323static int dummy_systimer_create(struct snd_pcm_substream *substream)
 324{
 325	struct dummy_systimer_pcm *dpcm;
 326
 327	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 328	if (!dpcm)
 329		return -ENOMEM;
 330	substream->runtime->private_data = dpcm;
 331	timer_setup(&dpcm->timer, dummy_systimer_callback, 0);
 
 332	spin_lock_init(&dpcm->lock);
 333	dpcm->substream = substream;
 334	return 0;
 335}
 336
 337static void dummy_systimer_free(struct snd_pcm_substream *substream)
 338{
 339	kfree(substream->runtime->private_data);
 340}
 341
 342static const struct dummy_timer_ops dummy_systimer_ops = {
 343	.create =	dummy_systimer_create,
 344	.free =		dummy_systimer_free,
 345	.prepare =	dummy_systimer_prepare,
 346	.start =	dummy_systimer_start,
 347	.stop =		dummy_systimer_stop,
 348	.pointer =	dummy_systimer_pointer,
 349};
 350
 351#ifdef CONFIG_HIGH_RES_TIMERS
 352/*
 353 * hrtimer interface
 354 */
 355
 356struct dummy_hrtimer_pcm {
 357	/* ops must be the first item */
 358	const struct dummy_timer_ops *timer_ops;
 359	ktime_t base_time;
 360	ktime_t period_time;
 361	atomic_t running;
 362	struct hrtimer timer;
 
 363	struct snd_pcm_substream *substream;
 364};
 365
 
 
 
 
 
 
 
 366static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 367{
 368	struct dummy_hrtimer_pcm *dpcm;
 369
 370	dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 371	if (!atomic_read(&dpcm->running))
 372		return HRTIMER_NORESTART;
 373	/*
 374	 * In cases of XRUN and draining, this calls .trigger to stop PCM
 375	 * substream.
 376	 */
 377	snd_pcm_period_elapsed(dpcm->substream);
 378	if (!atomic_read(&dpcm->running))
 379		return HRTIMER_NORESTART;
 380
 381	hrtimer_forward_now(timer, dpcm->period_time);
 382	return HRTIMER_RESTART;
 383}
 384
 385static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 386{
 387	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 388
 389	dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 390	hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL_SOFT);
 391	atomic_set(&dpcm->running, 1);
 392	return 0;
 393}
 394
 395static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 396{
 397	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 398
 399	atomic_set(&dpcm->running, 0);
 400	if (!hrtimer_callback_running(&dpcm->timer))
 401		hrtimer_cancel(&dpcm->timer);
 402	return 0;
 403}
 404
 405static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 406{
 407	hrtimer_cancel(&dpcm->timer);
 
 408}
 409
 410static snd_pcm_uframes_t
 411dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 412{
 413	struct snd_pcm_runtime *runtime = substream->runtime;
 414	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 415	u64 delta;
 416	u32 pos;
 417
 418	delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 419			       dpcm->base_time);
 420	delta = div_u64(delta * runtime->rate + 999999, 1000000);
 421	div_u64_rem(delta, runtime->buffer_size, &pos);
 422	return pos;
 423}
 424
 425static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 426{
 427	struct snd_pcm_runtime *runtime = substream->runtime;
 428	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 429	unsigned int period, rate;
 430	long sec;
 431	unsigned long nsecs;
 432
 433	dummy_hrtimer_sync(dpcm);
 434	period = runtime->period_size;
 435	rate = runtime->rate;
 436	sec = period / rate;
 437	period %= rate;
 438	nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 439	dpcm->period_time = ktime_set(sec, nsecs);
 440
 441	return 0;
 442}
 443
 444static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 445{
 446	struct dummy_hrtimer_pcm *dpcm;
 447
 448	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 449	if (!dpcm)
 450		return -ENOMEM;
 451	substream->runtime->private_data = dpcm;
 452	hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 453	dpcm->timer.function = dummy_hrtimer_callback;
 454	dpcm->substream = substream;
 455	atomic_set(&dpcm->running, 0);
 
 
 456	return 0;
 457}
 458
 459static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 460{
 461	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 462	dummy_hrtimer_sync(dpcm);
 463	kfree(dpcm);
 464}
 465
 466static const struct dummy_timer_ops dummy_hrtimer_ops = {
 467	.create =	dummy_hrtimer_create,
 468	.free =		dummy_hrtimer_free,
 469	.prepare =	dummy_hrtimer_prepare,
 470	.start =	dummy_hrtimer_start,
 471	.stop =		dummy_hrtimer_stop,
 472	.pointer =	dummy_hrtimer_pointer,
 473};
 474
 475#endif /* CONFIG_HIGH_RES_TIMERS */
 476
 477/*
 478 * PCM interface
 479 */
 480
 481static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 482{
 483	switch (cmd) {
 484	case SNDRV_PCM_TRIGGER_START:
 485	case SNDRV_PCM_TRIGGER_RESUME:
 486		return get_dummy_ops(substream)->start(substream);
 487	case SNDRV_PCM_TRIGGER_STOP:
 488	case SNDRV_PCM_TRIGGER_SUSPEND:
 489		return get_dummy_ops(substream)->stop(substream);
 490	}
 491	return -EINVAL;
 492}
 493
 494static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 495{
 496	return get_dummy_ops(substream)->prepare(substream);
 497}
 498
 499static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 500{
 501	return get_dummy_ops(substream)->pointer(substream);
 502}
 503
 504static const struct snd_pcm_hardware dummy_pcm_hardware = {
 505	.info =			(SNDRV_PCM_INFO_MMAP |
 506				 SNDRV_PCM_INFO_INTERLEAVED |
 507				 SNDRV_PCM_INFO_RESUME |
 508				 SNDRV_PCM_INFO_MMAP_VALID),
 509	.formats =		USE_FORMATS,
 510	.rates =		USE_RATE,
 511	.rate_min =		USE_RATE_MIN,
 512	.rate_max =		USE_RATE_MAX,
 513	.channels_min =		USE_CHANNELS_MIN,
 514	.channels_max =		USE_CHANNELS_MAX,
 515	.buffer_bytes_max =	MAX_BUFFER_SIZE,
 516	.period_bytes_min =	MIN_PERIOD_SIZE,
 517	.period_bytes_max =	MAX_PERIOD_SIZE,
 518	.periods_min =		USE_PERIODS_MIN,
 519	.periods_max =		USE_PERIODS_MAX,
 520	.fifo_size =		0,
 521};
 522
 523static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 524			       struct snd_pcm_hw_params *hw_params)
 525{
 526	if (fake_buffer) {
 527		/* runtime->dma_bytes has to be set manually to allow mmap */
 528		substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 529		return 0;
 530	}
 531	return 0;
 
 
 
 
 
 
 
 
 532}
 533
 534static int dummy_pcm_open(struct snd_pcm_substream *substream)
 535{
 536	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 537	const struct dummy_model *model = dummy->model;
 538	struct snd_pcm_runtime *runtime = substream->runtime;
 539	const struct dummy_timer_ops *ops;
 540	int err;
 541
 542	ops = &dummy_systimer_ops;
 543#ifdef CONFIG_HIGH_RES_TIMERS
 544	if (hrtimer)
 545		ops = &dummy_hrtimer_ops;
 546#endif
 547
 548	err = ops->create(substream);
 549	if (err < 0)
 550		return err;
 551	get_dummy_ops(substream) = ops;
 552
 553	runtime->hw = dummy->pcm_hw;
 554	if (substream->pcm->device & 1) {
 555		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 556		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 557	}
 558	if (substream->pcm->device & 2)
 559		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 560				      SNDRV_PCM_INFO_MMAP_VALID);
 561
 562	if (model == NULL)
 563		return 0;
 564
 565	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 566		if (model->playback_constraints)
 567			err = model->playback_constraints(substream->runtime);
 568	} else {
 569		if (model->capture_constraints)
 570			err = model->capture_constraints(substream->runtime);
 571	}
 572	if (err < 0) {
 573		get_dummy_ops(substream)->free(substream);
 574		return err;
 575	}
 576	return 0;
 577}
 578
 579static int dummy_pcm_close(struct snd_pcm_substream *substream)
 580{
 581	get_dummy_ops(substream)->free(substream);
 582	return 0;
 583}
 584
 585/*
 586 * dummy buffer handling
 587 */
 588
 589static void *dummy_page[2];
 590
 591static void free_fake_buffer(void)
 592{
 593	if (fake_buffer) {
 594		int i;
 595		for (i = 0; i < 2; i++)
 596			if (dummy_page[i]) {
 597				free_page((unsigned long)dummy_page[i]);
 598				dummy_page[i] = NULL;
 599			}
 600	}
 601}
 602
 603static int alloc_fake_buffer(void)
 604{
 605	int i;
 606
 607	if (!fake_buffer)
 608		return 0;
 609	for (i = 0; i < 2; i++) {
 610		dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 611		if (!dummy_page[i]) {
 612			free_fake_buffer();
 613			return -ENOMEM;
 614		}
 615	}
 616	return 0;
 617}
 618
 619static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 620			  int channel, unsigned long pos,
 621			  void __user *dst, unsigned long bytes)
 622{
 623	return 0; /* do nothing */
 624}
 625
 626static int dummy_pcm_copy_kernel(struct snd_pcm_substream *substream,
 627				 int channel, unsigned long pos,
 628				 void *dst, unsigned long bytes)
 629{
 630	return 0; /* do nothing */
 631}
 632
 633static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 634			     int channel, unsigned long pos,
 635			     unsigned long bytes)
 636{
 637	return 0; /* do nothing */
 638}
 639
 640static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 641				   unsigned long offset)
 642{
 643	return virt_to_page(dummy_page[substream->stream]); /* the same page */
 644}
 645
 646static const struct snd_pcm_ops dummy_pcm_ops = {
 647	.open =		dummy_pcm_open,
 648	.close =	dummy_pcm_close,
 
 649	.hw_params =	dummy_pcm_hw_params,
 
 650	.prepare =	dummy_pcm_prepare,
 651	.trigger =	dummy_pcm_trigger,
 652	.pointer =	dummy_pcm_pointer,
 653};
 654
 655static const struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 656	.open =		dummy_pcm_open,
 657	.close =	dummy_pcm_close,
 
 658	.hw_params =	dummy_pcm_hw_params,
 
 659	.prepare =	dummy_pcm_prepare,
 660	.trigger =	dummy_pcm_trigger,
 661	.pointer =	dummy_pcm_pointer,
 662	.copy_user =	dummy_pcm_copy,
 663	.copy_kernel =	dummy_pcm_copy_kernel,
 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 = -50;
 717	uinfo->value.integer.max = 100;
 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 < -50)
 743		left = -50;
 744	if (left > 100)
 745		left = 100;
 746	right = ucontrol->value.integer.value[1];
 747	if (right < -50)
 748		right = -50;
 749	if (right > 100)
 750		right = 100;
 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_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			printk(KERN_INFO
1037				"snd-dummy: Using model '%s' for card %i\n",
1038				(*mdl)->name, card->number);
1039			m = dummy->model = *mdl;
1040			break;
1041		}
1042	}
1043	for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1044		if (pcm_substreams[dev] < 1)
1045			pcm_substreams[dev] = 1;
1046		if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1047			pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1048		err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1049		if (err < 0)
1050			goto __nodev;
1051	}
1052
1053	dummy->pcm_hw = dummy_pcm_hardware;
1054	if (m) {
1055		if (m->formats)
1056			dummy->pcm_hw.formats = m->formats;
1057		if (m->buffer_bytes_max)
1058			dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1059		if (m->period_bytes_min)
1060			dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1061		if (m->period_bytes_max)
1062			dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1063		if (m->periods_min)
1064			dummy->pcm_hw.periods_min = m->periods_min;
1065		if (m->periods_max)
1066			dummy->pcm_hw.periods_max = m->periods_max;
1067		if (m->rates)
1068			dummy->pcm_hw.rates = m->rates;
1069		if (m->rate_min)
1070			dummy->pcm_hw.rate_min = m->rate_min;
1071		if (m->rate_max)
1072			dummy->pcm_hw.rate_max = m->rate_max;
1073		if (m->channels_min)
1074			dummy->pcm_hw.channels_min = m->channels_min;
1075		if (m->channels_max)
1076			dummy->pcm_hw.channels_max = m->channels_max;
1077	}
1078
1079	err = snd_card_dummy_new_mixer(dummy);
1080	if (err < 0)
1081		goto __nodev;
1082	strcpy(card->driver, "Dummy");
1083	strcpy(card->shortname, "Dummy");
1084	sprintf(card->longname, "Dummy %i", dev + 1);
1085
1086	dummy_proc_init(dummy);
1087
1088	err = snd_card_register(card);
1089	if (err == 0) {
1090		platform_set_drvdata(devptr, card);
1091		return 0;
1092	}
1093      __nodev:
1094	snd_card_free(card);
1095	return err;
1096}
1097
1098static int snd_dummy_remove(struct platform_device *devptr)
1099{
1100	snd_card_free(platform_get_drvdata(devptr));
1101	return 0;
1102}
1103
1104#ifdef CONFIG_PM_SLEEP
1105static int snd_dummy_suspend(struct device *pdev)
1106{
1107	struct snd_card *card = dev_get_drvdata(pdev);
 
1108
1109	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 
1110	return 0;
1111}
1112	
1113static int snd_dummy_resume(struct device *pdev)
1114{
1115	struct snd_card *card = dev_get_drvdata(pdev);
1116
1117	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1118	return 0;
1119}
1120
1121static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1122#define SND_DUMMY_PM_OPS	&snd_dummy_pm
1123#else
1124#define SND_DUMMY_PM_OPS	NULL
1125#endif
1126
1127#define SND_DUMMY_DRIVER	"snd_dummy"
1128
1129static struct platform_driver snd_dummy_driver = {
1130	.probe		= snd_dummy_probe,
1131	.remove		= snd_dummy_remove,
1132	.driver		= {
1133		.name	= SND_DUMMY_DRIVER,
1134		.pm	= SND_DUMMY_PM_OPS,
1135	},
1136};
1137
1138static void snd_dummy_unregister_all(void)
1139{
1140	int i;
1141
1142	for (i = 0; i < ARRAY_SIZE(devices); ++i)
1143		platform_device_unregister(devices[i]);
1144	platform_driver_unregister(&snd_dummy_driver);
1145	free_fake_buffer();
1146}
1147
1148static int __init alsa_card_dummy_init(void)
1149{
1150	int i, cards, err;
1151
1152	err = platform_driver_register(&snd_dummy_driver);
1153	if (err < 0)
1154		return err;
1155
1156	err = alloc_fake_buffer();
1157	if (err < 0) {
1158		platform_driver_unregister(&snd_dummy_driver);
1159		return err;
1160	}
1161
1162	cards = 0;
1163	for (i = 0; i < SNDRV_CARDS; i++) {
1164		struct platform_device *device;
1165		if (! enable[i])
1166			continue;
1167		device = platform_device_register_simple(SND_DUMMY_DRIVER,
1168							 i, NULL, 0);
1169		if (IS_ERR(device))
1170			continue;
1171		if (!platform_get_drvdata(device)) {
1172			platform_device_unregister(device);
1173			continue;
1174		}
1175		devices[i] = device;
1176		cards++;
1177	}
1178	if (!cards) {
1179#ifdef MODULE
1180		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1181#endif
1182		snd_dummy_unregister_all();
1183		return -ENODEV;
1184	}
1185	return 0;
1186}
1187
1188static void __exit alsa_card_dummy_exit(void)
1189{
1190	snd_dummy_unregister_all();
1191}
1192
1193module_init(alsa_card_dummy_init)
1194module_exit(alsa_card_dummy_exit)
v4.10.11
 
   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
 112#define get_dummy_ops(substream) \
 113	(*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
 114
 115struct dummy_model {
 116	const char *name;
 117	int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 118	int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 119	u64 formats;
 120	size_t buffer_bytes_max;
 121	size_t period_bytes_min;
 122	size_t period_bytes_max;
 123	unsigned int periods_min;
 124	unsigned int periods_max;
 125	unsigned int rates;
 126	unsigned int rate_min;
 127	unsigned int rate_max;
 128	unsigned int channels_min;
 129	unsigned int channels_max;
 130};
 131
 132struct snd_dummy {
 133	struct snd_card *card;
 134	struct dummy_model *model;
 135	struct snd_pcm *pcm;
 136	struct snd_pcm_hardware pcm_hw;
 137	spinlock_t mixer_lock;
 138	int mixer_volume[MIXER_ADDR_LAST+1][2];
 139	int capture_source[MIXER_ADDR_LAST+1][2];
 140	int iobox;
 141	struct snd_kcontrol *cd_volume_ctl;
 142	struct snd_kcontrol *cd_switch_ctl;
 143};
 144
 145/*
 146 * card models
 147 */
 148
 149static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 150{
 151	int err;
 152	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 153	if (err < 0)
 154		return err;
 155	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 156	if (err < 0)
 157		return err;
 158	return 0;
 159}
 160
 161static struct dummy_model model_emu10k1 = {
 162	.name = "emu10k1",
 163	.playback_constraints = emu10k1_playback_constraints,
 164	.buffer_bytes_max = 128 * 1024,
 165};
 166
 167static struct dummy_model model_rme9652 = {
 168	.name = "rme9652",
 169	.buffer_bytes_max = 26 * 64 * 1024,
 170	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 171	.channels_min = 26,
 172	.channels_max = 26,
 173	.periods_min = 2,
 174	.periods_max = 2,
 175};
 176
 177static struct dummy_model model_ice1712 = {
 178	.name = "ice1712",
 179	.buffer_bytes_max = 256 * 1024,
 180	.formats = SNDRV_PCM_FMTBIT_S32_LE,
 181	.channels_min = 10,
 182	.channels_max = 10,
 183	.periods_min = 1,
 184	.periods_max = 1024,
 185};
 186
 187static struct dummy_model model_uda1341 = {
 188	.name = "uda1341",
 189	.buffer_bytes_max = 16380,
 190	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 191	.channels_min = 2,
 192	.channels_max = 2,
 193	.periods_min = 2,
 194	.periods_max = 255,
 195};
 196
 197static struct dummy_model model_ac97 = {
 198	.name = "ac97",
 199	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 200	.channels_min = 2,
 201	.channels_max = 2,
 202	.rates = SNDRV_PCM_RATE_48000,
 203	.rate_min = 48000,
 204	.rate_max = 48000,
 205};
 206
 207static struct dummy_model model_ca0106 = {
 208	.name = "ca0106",
 209	.formats = SNDRV_PCM_FMTBIT_S16_LE,
 210	.buffer_bytes_max = ((65536-64)*8),
 211	.period_bytes_max = (65536-64),
 212	.periods_min = 2,
 213	.periods_max = 8,
 214	.channels_min = 2,
 215	.channels_max = 2,
 216	.rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 217	.rate_min = 48000,
 218	.rate_max = 192000,
 219};
 220
 221static struct dummy_model *dummy_models[] = {
 222	&model_emu10k1,
 223	&model_rme9652,
 224	&model_ice1712,
 225	&model_uda1341,
 226	&model_ac97,
 227	&model_ca0106,
 228	NULL
 229};
 230
 231/*
 232 * system timer interface
 233 */
 234
 235struct dummy_systimer_pcm {
 236	/* ops must be the first item */
 237	const struct dummy_timer_ops *timer_ops;
 238	spinlock_t lock;
 239	struct timer_list timer;
 240	unsigned long base_time;
 241	unsigned int frac_pos;	/* fractional sample position (based HZ) */
 242	unsigned int frac_period_rest;
 243	unsigned int frac_buffer_size;	/* buffer_size * HZ */
 244	unsigned int frac_period_size;	/* period_size * HZ */
 245	unsigned int rate;
 246	int elapsed;
 247	struct snd_pcm_substream *substream;
 248};
 249
 250static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 251{
 252	mod_timer(&dpcm->timer, jiffies +
 253		(dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate);
 254}
 255
 256static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 257{
 258	unsigned long delta;
 259
 260	delta = jiffies - dpcm->base_time;
 261	if (!delta)
 262		return;
 263	dpcm->base_time += delta;
 264	delta *= dpcm->rate;
 265	dpcm->frac_pos += delta;
 266	while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 267		dpcm->frac_pos -= dpcm->frac_buffer_size;
 268	while (dpcm->frac_period_rest <= delta) {
 269		dpcm->elapsed++;
 270		dpcm->frac_period_rest += dpcm->frac_period_size;
 271	}
 272	dpcm->frac_period_rest -= delta;
 273}
 274
 275static int dummy_systimer_start(struct snd_pcm_substream *substream)
 276{
 277	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 278	spin_lock(&dpcm->lock);
 279	dpcm->base_time = jiffies;
 280	dummy_systimer_rearm(dpcm);
 281	spin_unlock(&dpcm->lock);
 282	return 0;
 283}
 284
 285static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 286{
 287	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 288	spin_lock(&dpcm->lock);
 289	del_timer(&dpcm->timer);
 290	spin_unlock(&dpcm->lock);
 291	return 0;
 292}
 293
 294static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 295{
 296	struct snd_pcm_runtime *runtime = substream->runtime;
 297	struct dummy_systimer_pcm *dpcm = runtime->private_data;
 298
 299	dpcm->frac_pos = 0;
 300	dpcm->rate = runtime->rate;
 301	dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 302	dpcm->frac_period_size = runtime->period_size * HZ;
 303	dpcm->frac_period_rest = dpcm->frac_period_size;
 304	dpcm->elapsed = 0;
 305
 306	return 0;
 307}
 308
 309static void dummy_systimer_callback(unsigned long data)
 310{
 311	struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 312	unsigned long flags;
 313	int elapsed = 0;
 314	
 315	spin_lock_irqsave(&dpcm->lock, flags);
 316	dummy_systimer_update(dpcm);
 317	dummy_systimer_rearm(dpcm);
 318	elapsed = dpcm->elapsed;
 319	dpcm->elapsed = 0;
 320	spin_unlock_irqrestore(&dpcm->lock, flags);
 321	if (elapsed)
 322		snd_pcm_period_elapsed(dpcm->substream);
 323}
 324
 325static snd_pcm_uframes_t
 326dummy_systimer_pointer(struct snd_pcm_substream *substream)
 327{
 328	struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 329	snd_pcm_uframes_t pos;
 330
 331	spin_lock(&dpcm->lock);
 332	dummy_systimer_update(dpcm);
 333	pos = dpcm->frac_pos / HZ;
 334	spin_unlock(&dpcm->lock);
 335	return pos;
 336}
 337
 338static int dummy_systimer_create(struct snd_pcm_substream *substream)
 339{
 340	struct dummy_systimer_pcm *dpcm;
 341
 342	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 343	if (!dpcm)
 344		return -ENOMEM;
 345	substream->runtime->private_data = dpcm;
 346	setup_timer(&dpcm->timer, dummy_systimer_callback,
 347			(unsigned long) dpcm);
 348	spin_lock_init(&dpcm->lock);
 349	dpcm->substream = substream;
 350	return 0;
 351}
 352
 353static void dummy_systimer_free(struct snd_pcm_substream *substream)
 354{
 355	kfree(substream->runtime->private_data);
 356}
 357
 358static const struct dummy_timer_ops dummy_systimer_ops = {
 359	.create =	dummy_systimer_create,
 360	.free =		dummy_systimer_free,
 361	.prepare =	dummy_systimer_prepare,
 362	.start =	dummy_systimer_start,
 363	.stop =		dummy_systimer_stop,
 364	.pointer =	dummy_systimer_pointer,
 365};
 366
 367#ifdef CONFIG_HIGH_RES_TIMERS
 368/*
 369 * hrtimer interface
 370 */
 371
 372struct dummy_hrtimer_pcm {
 373	/* ops must be the first item */
 374	const struct dummy_timer_ops *timer_ops;
 375	ktime_t base_time;
 376	ktime_t period_time;
 377	atomic_t running;
 378	struct hrtimer timer;
 379	struct tasklet_struct tasklet;
 380	struct snd_pcm_substream *substream;
 381};
 382
 383static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 384{
 385	struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 386	if (atomic_read(&dpcm->running))
 387		snd_pcm_period_elapsed(dpcm->substream);
 388}
 389
 390static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 391{
 392	struct dummy_hrtimer_pcm *dpcm;
 393
 394	dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 395	if (!atomic_read(&dpcm->running))
 396		return HRTIMER_NORESTART;
 397	tasklet_schedule(&dpcm->tasklet);
 
 
 
 
 
 
 
 398	hrtimer_forward_now(timer, dpcm->period_time);
 399	return HRTIMER_RESTART;
 400}
 401
 402static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 403{
 404	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 405
 406	dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 407	hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 408	atomic_set(&dpcm->running, 1);
 409	return 0;
 410}
 411
 412static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 413{
 414	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 415
 416	atomic_set(&dpcm->running, 0);
 417	hrtimer_cancel(&dpcm->timer);
 
 418	return 0;
 419}
 420
 421static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 422{
 423	hrtimer_cancel(&dpcm->timer);
 424	tasklet_kill(&dpcm->tasklet);
 425}
 426
 427static snd_pcm_uframes_t
 428dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 429{
 430	struct snd_pcm_runtime *runtime = substream->runtime;
 431	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 432	u64 delta;
 433	u32 pos;
 434
 435	delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 436			       dpcm->base_time);
 437	delta = div_u64(delta * runtime->rate + 999999, 1000000);
 438	div_u64_rem(delta, runtime->buffer_size, &pos);
 439	return pos;
 440}
 441
 442static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 443{
 444	struct snd_pcm_runtime *runtime = substream->runtime;
 445	struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 446	unsigned int period, rate;
 447	long sec;
 448	unsigned long nsecs;
 449
 450	dummy_hrtimer_sync(dpcm);
 451	period = runtime->period_size;
 452	rate = runtime->rate;
 453	sec = period / rate;
 454	period %= rate;
 455	nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 456	dpcm->period_time = ktime_set(sec, nsecs);
 457
 458	return 0;
 459}
 460
 461static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 462{
 463	struct dummy_hrtimer_pcm *dpcm;
 464
 465	dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 466	if (!dpcm)
 467		return -ENOMEM;
 468	substream->runtime->private_data = dpcm;
 469	hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 470	dpcm->timer.function = dummy_hrtimer_callback;
 471	dpcm->substream = substream;
 472	atomic_set(&dpcm->running, 0);
 473	tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 474		     (unsigned long)dpcm);
 475	return 0;
 476}
 477
 478static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 479{
 480	struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 481	dummy_hrtimer_sync(dpcm);
 482	kfree(dpcm);
 483}
 484
 485static const struct dummy_timer_ops dummy_hrtimer_ops = {
 486	.create =	dummy_hrtimer_create,
 487	.free =		dummy_hrtimer_free,
 488	.prepare =	dummy_hrtimer_prepare,
 489	.start =	dummy_hrtimer_start,
 490	.stop =		dummy_hrtimer_stop,
 491	.pointer =	dummy_hrtimer_pointer,
 492};
 493
 494#endif /* CONFIG_HIGH_RES_TIMERS */
 495
 496/*
 497 * PCM interface
 498 */
 499
 500static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 501{
 502	switch (cmd) {
 503	case SNDRV_PCM_TRIGGER_START:
 504	case SNDRV_PCM_TRIGGER_RESUME:
 505		return get_dummy_ops(substream)->start(substream);
 506	case SNDRV_PCM_TRIGGER_STOP:
 507	case SNDRV_PCM_TRIGGER_SUSPEND:
 508		return get_dummy_ops(substream)->stop(substream);
 509	}
 510	return -EINVAL;
 511}
 512
 513static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 514{
 515	return get_dummy_ops(substream)->prepare(substream);
 516}
 517
 518static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 519{
 520	return get_dummy_ops(substream)->pointer(substream);
 521}
 522
 523static struct snd_pcm_hardware dummy_pcm_hardware = {
 524	.info =			(SNDRV_PCM_INFO_MMAP |
 525				 SNDRV_PCM_INFO_INTERLEAVED |
 526				 SNDRV_PCM_INFO_RESUME |
 527				 SNDRV_PCM_INFO_MMAP_VALID),
 528	.formats =		USE_FORMATS,
 529	.rates =		USE_RATE,
 530	.rate_min =		USE_RATE_MIN,
 531	.rate_max =		USE_RATE_MAX,
 532	.channels_min =		USE_CHANNELS_MIN,
 533	.channels_max =		USE_CHANNELS_MAX,
 534	.buffer_bytes_max =	MAX_BUFFER_SIZE,
 535	.period_bytes_min =	MIN_PERIOD_SIZE,
 536	.period_bytes_max =	MAX_PERIOD_SIZE,
 537	.periods_min =		USE_PERIODS_MIN,
 538	.periods_max =		USE_PERIODS_MAX,
 539	.fifo_size =		0,
 540};
 541
 542static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 543			       struct snd_pcm_hw_params *hw_params)
 544{
 545	if (fake_buffer) {
 546		/* runtime->dma_bytes has to be set manually to allow mmap */
 547		substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 548		return 0;
 549	}
 550	return snd_pcm_lib_malloc_pages(substream,
 551					params_buffer_bytes(hw_params));
 552}
 553
 554static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 555{
 556	if (fake_buffer)
 557		return 0;
 558	return snd_pcm_lib_free_pages(substream);
 559}
 560
 561static int dummy_pcm_open(struct snd_pcm_substream *substream)
 562{
 563	struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 564	struct dummy_model *model = dummy->model;
 565	struct snd_pcm_runtime *runtime = substream->runtime;
 566	const struct dummy_timer_ops *ops;
 567	int err;
 568
 569	ops = &dummy_systimer_ops;
 570#ifdef CONFIG_HIGH_RES_TIMERS
 571	if (hrtimer)
 572		ops = &dummy_hrtimer_ops;
 573#endif
 574
 575	err = ops->create(substream);
 576	if (err < 0)
 577		return err;
 578	get_dummy_ops(substream) = ops;
 579
 580	runtime->hw = dummy->pcm_hw;
 581	if (substream->pcm->device & 1) {
 582		runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 583		runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 584	}
 585	if (substream->pcm->device & 2)
 586		runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 587				      SNDRV_PCM_INFO_MMAP_VALID);
 588
 589	if (model == NULL)
 590		return 0;
 591
 592	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 593		if (model->playback_constraints)
 594			err = model->playback_constraints(substream->runtime);
 595	} else {
 596		if (model->capture_constraints)
 597			err = model->capture_constraints(substream->runtime);
 598	}
 599	if (err < 0) {
 600		get_dummy_ops(substream)->free(substream);
 601		return err;
 602	}
 603	return 0;
 604}
 605
 606static int dummy_pcm_close(struct snd_pcm_substream *substream)
 607{
 608	get_dummy_ops(substream)->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_SND_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_SND_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		.pm	= SND_DUMMY_PM_OPS,
1166	},
1167};
1168
1169static void snd_dummy_unregister_all(void)
1170{
1171	int i;
1172
1173	for (i = 0; i < ARRAY_SIZE(devices); ++i)
1174		platform_device_unregister(devices[i]);
1175	platform_driver_unregister(&snd_dummy_driver);
1176	free_fake_buffer();
1177}
1178
1179static int __init alsa_card_dummy_init(void)
1180{
1181	int i, cards, err;
1182
1183	err = platform_driver_register(&snd_dummy_driver);
1184	if (err < 0)
1185		return err;
1186
1187	err = alloc_fake_buffer();
1188	if (err < 0) {
1189		platform_driver_unregister(&snd_dummy_driver);
1190		return err;
1191	}
1192
1193	cards = 0;
1194	for (i = 0; i < SNDRV_CARDS; i++) {
1195		struct platform_device *device;
1196		if (! enable[i])
1197			continue;
1198		device = platform_device_register_simple(SND_DUMMY_DRIVER,
1199							 i, NULL, 0);
1200		if (IS_ERR(device))
1201			continue;
1202		if (!platform_get_drvdata(device)) {
1203			platform_device_unregister(device);
1204			continue;
1205		}
1206		devices[i] = device;
1207		cards++;
1208	}
1209	if (!cards) {
1210#ifdef MODULE
1211		printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1212#endif
1213		snd_dummy_unregister_all();
1214		return -ENODEV;
1215	}
1216	return 0;
1217}
1218
1219static void __exit alsa_card_dummy_exit(void)
1220{
1221	snd_dummy_unregister_all();
1222}
1223
1224module_init(alsa_card_dummy_init)
1225module_exit(alsa_card_dummy_exit)