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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)
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)