xref: /linux/sound/core/pcm.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  *  Digital Audio (PCM) abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 
22 #include <linux/init.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/time.h>
26 #include <linux/mutex.h>
27 #include <linux/device.h>
28 #include <sound/core.h>
29 #include <sound/minors.h>
30 #include <sound/pcm.h>
31 #include <sound/control.h>
32 #include <sound/info.h>
33 
34 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
35 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
36 MODULE_LICENSE("GPL");
37 
38 static LIST_HEAD(snd_pcm_devices);
39 static LIST_HEAD(snd_pcm_notify_list);
40 static DEFINE_MUTEX(register_mutex);
41 
42 static int snd_pcm_free(struct snd_pcm *pcm);
43 static int snd_pcm_dev_free(struct snd_device *device);
44 static int snd_pcm_dev_register(struct snd_device *device);
45 static int snd_pcm_dev_disconnect(struct snd_device *device);
46 
47 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
48 {
49 	struct snd_pcm *pcm;
50 
51 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
52 		if (pcm->internal)
53 			continue;
54 		if (pcm->card == card && pcm->device == device)
55 			return pcm;
56 	}
57 	return NULL;
58 }
59 
60 static int snd_pcm_next(struct snd_card *card, int device)
61 {
62 	struct snd_pcm *pcm;
63 
64 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
65 		if (pcm->internal)
66 			continue;
67 		if (pcm->card == card && pcm->device > device)
68 			return pcm->device;
69 		else if (pcm->card->number > card->number)
70 			return -1;
71 	}
72 	return -1;
73 }
74 
75 static int snd_pcm_add(struct snd_pcm *newpcm)
76 {
77 	struct snd_pcm *pcm;
78 
79 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
80 		if (pcm->card == newpcm->card && pcm->device == newpcm->device)
81 			return -EBUSY;
82 		if (pcm->card->number > newpcm->card->number ||
83 				(pcm->card == newpcm->card &&
84 				pcm->device > newpcm->device)) {
85 			list_add(&newpcm->list, pcm->list.prev);
86 			return 0;
87 		}
88 	}
89 	list_add_tail(&newpcm->list, &snd_pcm_devices);
90 	return 0;
91 }
92 
93 static int snd_pcm_control_ioctl(struct snd_card *card,
94 				 struct snd_ctl_file *control,
95 				 unsigned int cmd, unsigned long arg)
96 {
97 	switch (cmd) {
98 	case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
99 		{
100 			int device;
101 
102 			if (get_user(device, (int __user *)arg))
103 				return -EFAULT;
104 			mutex_lock(&register_mutex);
105 			device = snd_pcm_next(card, device);
106 			mutex_unlock(&register_mutex);
107 			if (put_user(device, (int __user *)arg))
108 				return -EFAULT;
109 			return 0;
110 		}
111 	case SNDRV_CTL_IOCTL_PCM_INFO:
112 		{
113 			struct snd_pcm_info __user *info;
114 			unsigned int device, subdevice;
115 			int stream;
116 			struct snd_pcm *pcm;
117 			struct snd_pcm_str *pstr;
118 			struct snd_pcm_substream *substream;
119 			int err;
120 
121 			info = (struct snd_pcm_info __user *)arg;
122 			if (get_user(device, &info->device))
123 				return -EFAULT;
124 			if (get_user(stream, &info->stream))
125 				return -EFAULT;
126 			if (stream < 0 || stream > 1)
127 				return -EINVAL;
128 			if (get_user(subdevice, &info->subdevice))
129 				return -EFAULT;
130 			mutex_lock(&register_mutex);
131 			pcm = snd_pcm_get(card, device);
132 			if (pcm == NULL) {
133 				err = -ENXIO;
134 				goto _error;
135 			}
136 			pstr = &pcm->streams[stream];
137 			if (pstr->substream_count == 0) {
138 				err = -ENOENT;
139 				goto _error;
140 			}
141 			if (subdevice >= pstr->substream_count) {
142 				err = -ENXIO;
143 				goto _error;
144 			}
145 			for (substream = pstr->substream; substream;
146 			     substream = substream->next)
147 				if (substream->number == (int)subdevice)
148 					break;
149 			if (substream == NULL) {
150 				err = -ENXIO;
151 				goto _error;
152 			}
153 			err = snd_pcm_info_user(substream, info);
154 		_error:
155 			mutex_unlock(&register_mutex);
156 			return err;
157 		}
158 	case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
159 		{
160 			int val;
161 
162 			if (get_user(val, (int __user *)arg))
163 				return -EFAULT;
164 			control->prefer_pcm_subdevice = val;
165 			return 0;
166 		}
167 	}
168 	return -ENOIOCTLCMD;
169 }
170 
171 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
172 
173 static char *snd_pcm_format_names[] = {
174 	FORMAT(S8),
175 	FORMAT(U8),
176 	FORMAT(S16_LE),
177 	FORMAT(S16_BE),
178 	FORMAT(U16_LE),
179 	FORMAT(U16_BE),
180 	FORMAT(S24_LE),
181 	FORMAT(S24_BE),
182 	FORMAT(U24_LE),
183 	FORMAT(U24_BE),
184 	FORMAT(S32_LE),
185 	FORMAT(S32_BE),
186 	FORMAT(U32_LE),
187 	FORMAT(U32_BE),
188 	FORMAT(FLOAT_LE),
189 	FORMAT(FLOAT_BE),
190 	FORMAT(FLOAT64_LE),
191 	FORMAT(FLOAT64_BE),
192 	FORMAT(IEC958_SUBFRAME_LE),
193 	FORMAT(IEC958_SUBFRAME_BE),
194 	FORMAT(MU_LAW),
195 	FORMAT(A_LAW),
196 	FORMAT(IMA_ADPCM),
197 	FORMAT(MPEG),
198 	FORMAT(GSM),
199 	FORMAT(SPECIAL),
200 	FORMAT(S24_3LE),
201 	FORMAT(S24_3BE),
202 	FORMAT(U24_3LE),
203 	FORMAT(U24_3BE),
204 	FORMAT(S20_3LE),
205 	FORMAT(S20_3BE),
206 	FORMAT(U20_3LE),
207 	FORMAT(U20_3BE),
208 	FORMAT(S18_3LE),
209 	FORMAT(S18_3BE),
210 	FORMAT(U18_3LE),
211 	FORMAT(U18_3BE),
212 	FORMAT(G723_24),
213 	FORMAT(G723_24_1B),
214 	FORMAT(G723_40),
215 	FORMAT(G723_40_1B),
216 	FORMAT(DSD_U8),
217 	FORMAT(DSD_U16_LE),
218 };
219 
220 const char *snd_pcm_format_name(snd_pcm_format_t format)
221 {
222 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
223 		return "Unknown";
224 	return snd_pcm_format_names[(__force unsigned int)format];
225 }
226 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
227 
228 #ifdef CONFIG_SND_VERBOSE_PROCFS
229 
230 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
231 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
232 #define READY(v) [SNDRV_PCM_READY_##v] = #v
233 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
234 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
235 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
236 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
237 #define START(v) [SNDRV_PCM_START_##v] = #v
238 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
239 
240 static char *snd_pcm_stream_names[] = {
241 	STREAM(PLAYBACK),
242 	STREAM(CAPTURE),
243 };
244 
245 static char *snd_pcm_state_names[] = {
246 	STATE(OPEN),
247 	STATE(SETUP),
248 	STATE(PREPARED),
249 	STATE(RUNNING),
250 	STATE(XRUN),
251 	STATE(DRAINING),
252 	STATE(PAUSED),
253 	STATE(SUSPENDED),
254 };
255 
256 static char *snd_pcm_access_names[] = {
257 	ACCESS(MMAP_INTERLEAVED),
258 	ACCESS(MMAP_NONINTERLEAVED),
259 	ACCESS(MMAP_COMPLEX),
260 	ACCESS(RW_INTERLEAVED),
261 	ACCESS(RW_NONINTERLEAVED),
262 };
263 
264 static char *snd_pcm_subformat_names[] = {
265 	SUBFORMAT(STD),
266 };
267 
268 static char *snd_pcm_tstamp_mode_names[] = {
269 	TSTAMP(NONE),
270 	TSTAMP(ENABLE),
271 };
272 
273 static const char *snd_pcm_stream_name(int stream)
274 {
275 	return snd_pcm_stream_names[stream];
276 }
277 
278 static const char *snd_pcm_access_name(snd_pcm_access_t access)
279 {
280 	return snd_pcm_access_names[(__force int)access];
281 }
282 
283 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
284 {
285 	return snd_pcm_subformat_names[(__force int)subformat];
286 }
287 
288 static const char *snd_pcm_tstamp_mode_name(int mode)
289 {
290 	return snd_pcm_tstamp_mode_names[mode];
291 }
292 
293 static const char *snd_pcm_state_name(snd_pcm_state_t state)
294 {
295 	return snd_pcm_state_names[(__force int)state];
296 }
297 
298 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
299 #include <linux/soundcard.h>
300 
301 static const char *snd_pcm_oss_format_name(int format)
302 {
303 	switch (format) {
304 	case AFMT_MU_LAW:
305 		return "MU_LAW";
306 	case AFMT_A_LAW:
307 		return "A_LAW";
308 	case AFMT_IMA_ADPCM:
309 		return "IMA_ADPCM";
310 	case AFMT_U8:
311 		return "U8";
312 	case AFMT_S16_LE:
313 		return "S16_LE";
314 	case AFMT_S16_BE:
315 		return "S16_BE";
316 	case AFMT_S8:
317 		return "S8";
318 	case AFMT_U16_LE:
319 		return "U16_LE";
320 	case AFMT_U16_BE:
321 		return "U16_BE";
322 	case AFMT_MPEG:
323 		return "MPEG";
324 	default:
325 		return "unknown";
326 	}
327 }
328 #endif
329 
330 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
331 				   struct snd_info_buffer *buffer)
332 {
333 	struct snd_pcm_info *info;
334 	int err;
335 
336 	if (! substream)
337 		return;
338 
339 	info = kmalloc(sizeof(*info), GFP_KERNEL);
340 	if (! info) {
341 		printk(KERN_DEBUG "snd_pcm_proc_info_read: cannot malloc\n");
342 		return;
343 	}
344 
345 	err = snd_pcm_info(substream, info);
346 	if (err < 0) {
347 		snd_iprintf(buffer, "error %d\n", err);
348 		kfree(info);
349 		return;
350 	}
351 	snd_iprintf(buffer, "card: %d\n", info->card);
352 	snd_iprintf(buffer, "device: %d\n", info->device);
353 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
354 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
355 	snd_iprintf(buffer, "id: %s\n", info->id);
356 	snd_iprintf(buffer, "name: %s\n", info->name);
357 	snd_iprintf(buffer, "subname: %s\n", info->subname);
358 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
359 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
360 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
361 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
362 	kfree(info);
363 }
364 
365 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
366 					  struct snd_info_buffer *buffer)
367 {
368 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
369 			       buffer);
370 }
371 
372 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
373 					     struct snd_info_buffer *buffer)
374 {
375 	snd_pcm_proc_info_read(entry->private_data, buffer);
376 }
377 
378 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
379 						  struct snd_info_buffer *buffer)
380 {
381 	struct snd_pcm_substream *substream = entry->private_data;
382 	struct snd_pcm_runtime *runtime;
383 
384 	mutex_lock(&substream->pcm->open_mutex);
385 	runtime = substream->runtime;
386 	if (!runtime) {
387 		snd_iprintf(buffer, "closed\n");
388 		goto unlock;
389 	}
390 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
391 		snd_iprintf(buffer, "no setup\n");
392 		goto unlock;
393 	}
394 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
395 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
396 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
397 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
398 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
399 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
400 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
401 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
402 	if (substream->oss.oss) {
403 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
404 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
405 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
406 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
407 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
408 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
409 	}
410 #endif
411  unlock:
412 	mutex_unlock(&substream->pcm->open_mutex);
413 }
414 
415 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
416 						  struct snd_info_buffer *buffer)
417 {
418 	struct snd_pcm_substream *substream = entry->private_data;
419 	struct snd_pcm_runtime *runtime;
420 
421 	mutex_lock(&substream->pcm->open_mutex);
422 	runtime = substream->runtime;
423 	if (!runtime) {
424 		snd_iprintf(buffer, "closed\n");
425 		goto unlock;
426 	}
427 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
428 		snd_iprintf(buffer, "no setup\n");
429 		goto unlock;
430 	}
431 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
432 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
433 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
434 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
435 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
436 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
437 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
438 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
439  unlock:
440 	mutex_unlock(&substream->pcm->open_mutex);
441 }
442 
443 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
444 					       struct snd_info_buffer *buffer)
445 {
446 	struct snd_pcm_substream *substream = entry->private_data;
447 	struct snd_pcm_runtime *runtime;
448 	struct snd_pcm_status status;
449 	int err;
450 
451 	mutex_lock(&substream->pcm->open_mutex);
452 	runtime = substream->runtime;
453 	if (!runtime) {
454 		snd_iprintf(buffer, "closed\n");
455 		goto unlock;
456 	}
457 	memset(&status, 0, sizeof(status));
458 	err = snd_pcm_status(substream, &status);
459 	if (err < 0) {
460 		snd_iprintf(buffer, "error %d\n", err);
461 		goto unlock;
462 	}
463 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
464 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
465 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
466 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
467 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
468 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
469 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
470 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
471 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
472 	snd_iprintf(buffer, "-----\n");
473 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
474 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
475  unlock:
476 	mutex_unlock(&substream->pcm->open_mutex);
477 }
478 
479 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
480 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
481 				    struct snd_info_buffer *buffer)
482 {
483 	struct snd_pcm_str *pstr = entry->private_data;
484 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
485 }
486 
487 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
488 				     struct snd_info_buffer *buffer)
489 {
490 	struct snd_pcm_str *pstr = entry->private_data;
491 	char line[64];
492 	if (!snd_info_get_line(buffer, line, sizeof(line)))
493 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
494 }
495 #endif
496 
497 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
498 {
499 	struct snd_pcm *pcm = pstr->pcm;
500 	struct snd_info_entry *entry;
501 	char name[16];
502 
503 	sprintf(name, "pcm%i%c", pcm->device,
504 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
505 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
506 		return -ENOMEM;
507 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
508 	if (snd_info_register(entry) < 0) {
509 		snd_info_free_entry(entry);
510 		return -ENOMEM;
511 	}
512 	pstr->proc_root = entry;
513 
514 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
515 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
516 		if (snd_info_register(entry) < 0) {
517 			snd_info_free_entry(entry);
518 			entry = NULL;
519 		}
520 	}
521 	pstr->proc_info_entry = entry;
522 
523 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
524 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
525 						pstr->proc_root)) != NULL) {
526 		entry->c.text.read = snd_pcm_xrun_debug_read;
527 		entry->c.text.write = snd_pcm_xrun_debug_write;
528 		entry->mode |= S_IWUSR;
529 		entry->private_data = pstr;
530 		if (snd_info_register(entry) < 0) {
531 			snd_info_free_entry(entry);
532 			entry = NULL;
533 		}
534 	}
535 	pstr->proc_xrun_debug_entry = entry;
536 #endif
537 	return 0;
538 }
539 
540 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
541 {
542 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
543 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
544 	pstr->proc_xrun_debug_entry = NULL;
545 #endif
546 	snd_info_free_entry(pstr->proc_info_entry);
547 	pstr->proc_info_entry = NULL;
548 	snd_info_free_entry(pstr->proc_root);
549 	pstr->proc_root = NULL;
550 	return 0;
551 }
552 
553 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
554 {
555 	struct snd_info_entry *entry;
556 	struct snd_card *card;
557 	char name[16];
558 
559 	card = substream->pcm->card;
560 
561 	sprintf(name, "sub%i", substream->number);
562 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
563 		return -ENOMEM;
564 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
565 	if (snd_info_register(entry) < 0) {
566 		snd_info_free_entry(entry);
567 		return -ENOMEM;
568 	}
569 	substream->proc_root = entry;
570 
571 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
572 		snd_info_set_text_ops(entry, substream,
573 				      snd_pcm_substream_proc_info_read);
574 		if (snd_info_register(entry) < 0) {
575 			snd_info_free_entry(entry);
576 			entry = NULL;
577 		}
578 	}
579 	substream->proc_info_entry = entry;
580 
581 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
582 		snd_info_set_text_ops(entry, substream,
583 				      snd_pcm_substream_proc_hw_params_read);
584 		if (snd_info_register(entry) < 0) {
585 			snd_info_free_entry(entry);
586 			entry = NULL;
587 		}
588 	}
589 	substream->proc_hw_params_entry = entry;
590 
591 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
592 		snd_info_set_text_ops(entry, substream,
593 				      snd_pcm_substream_proc_sw_params_read);
594 		if (snd_info_register(entry) < 0) {
595 			snd_info_free_entry(entry);
596 			entry = NULL;
597 		}
598 	}
599 	substream->proc_sw_params_entry = entry;
600 
601 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
602 		snd_info_set_text_ops(entry, substream,
603 				      snd_pcm_substream_proc_status_read);
604 		if (snd_info_register(entry) < 0) {
605 			snd_info_free_entry(entry);
606 			entry = NULL;
607 		}
608 	}
609 	substream->proc_status_entry = entry;
610 
611 	return 0;
612 }
613 
614 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
615 {
616 	snd_info_free_entry(substream->proc_info_entry);
617 	substream->proc_info_entry = NULL;
618 	snd_info_free_entry(substream->proc_hw_params_entry);
619 	substream->proc_hw_params_entry = NULL;
620 	snd_info_free_entry(substream->proc_sw_params_entry);
621 	substream->proc_sw_params_entry = NULL;
622 	snd_info_free_entry(substream->proc_status_entry);
623 	substream->proc_status_entry = NULL;
624 	snd_info_free_entry(substream->proc_root);
625 	substream->proc_root = NULL;
626 	return 0;
627 }
628 #else /* !CONFIG_SND_VERBOSE_PROCFS */
629 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
630 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
631 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
632 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
633 #endif /* CONFIG_SND_VERBOSE_PROCFS */
634 
635 /**
636  * snd_pcm_new_stream - create a new PCM stream
637  * @pcm: the pcm instance
638  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
639  * @substream_count: the number of substreams
640  *
641  * Creates a new stream for the pcm.
642  * The corresponding stream on the pcm must have been empty before
643  * calling this, i.e. zero must be given to the argument of
644  * snd_pcm_new().
645  *
646  * Return: Zero if successful, or a negative error code on failure.
647  */
648 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
649 {
650 	int idx, err;
651 	struct snd_pcm_str *pstr = &pcm->streams[stream];
652 	struct snd_pcm_substream *substream, *prev;
653 
654 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
655 	mutex_init(&pstr->oss.setup_mutex);
656 #endif
657 	pstr->stream = stream;
658 	pstr->pcm = pcm;
659 	pstr->substream_count = substream_count;
660 	if (substream_count > 0 && !pcm->internal) {
661 		err = snd_pcm_stream_proc_init(pstr);
662 		if (err < 0) {
663 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
664 			return err;
665 		}
666 	}
667 	prev = NULL;
668 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
669 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
670 		if (substream == NULL) {
671 			snd_printk(KERN_ERR "Cannot allocate PCM substream\n");
672 			return -ENOMEM;
673 		}
674 		substream->pcm = pcm;
675 		substream->pstr = pstr;
676 		substream->number = idx;
677 		substream->stream = stream;
678 		sprintf(substream->name, "subdevice #%i", idx);
679 		substream->buffer_bytes_max = UINT_MAX;
680 		if (prev == NULL)
681 			pstr->substream = substream;
682 		else
683 			prev->next = substream;
684 
685 		if (!pcm->internal) {
686 			err = snd_pcm_substream_proc_init(substream);
687 			if (err < 0) {
688 				snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
689 				if (prev == NULL)
690 					pstr->substream = NULL;
691 				else
692 					prev->next = NULL;
693 				kfree(substream);
694 				return err;
695 			}
696 		}
697 		substream->group = &substream->self_group;
698 		spin_lock_init(&substream->self_group.lock);
699 		INIT_LIST_HEAD(&substream->self_group.substreams);
700 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
701 		atomic_set(&substream->mmap_count, 0);
702 		prev = substream;
703 	}
704 	return 0;
705 }
706 
707 EXPORT_SYMBOL(snd_pcm_new_stream);
708 
709 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
710 		int playback_count, int capture_count, bool internal,
711 		struct snd_pcm **rpcm)
712 {
713 	struct snd_pcm *pcm;
714 	int err;
715 	static struct snd_device_ops ops = {
716 		.dev_free = snd_pcm_dev_free,
717 		.dev_register =	snd_pcm_dev_register,
718 		.dev_disconnect = snd_pcm_dev_disconnect,
719 	};
720 
721 	if (snd_BUG_ON(!card))
722 		return -ENXIO;
723 	if (rpcm)
724 		*rpcm = NULL;
725 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
726 	if (pcm == NULL) {
727 		snd_printk(KERN_ERR "Cannot allocate PCM\n");
728 		return -ENOMEM;
729 	}
730 	pcm->card = card;
731 	pcm->device = device;
732 	pcm->internal = internal;
733 	if (id)
734 		strlcpy(pcm->id, id, sizeof(pcm->id));
735 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
736 		snd_pcm_free(pcm);
737 		return err;
738 	}
739 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
740 		snd_pcm_free(pcm);
741 		return err;
742 	}
743 	mutex_init(&pcm->open_mutex);
744 	init_waitqueue_head(&pcm->open_wait);
745 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
746 		snd_pcm_free(pcm);
747 		return err;
748 	}
749 	if (rpcm)
750 		*rpcm = pcm;
751 	return 0;
752 }
753 
754 /**
755  * snd_pcm_new - create a new PCM instance
756  * @card: the card instance
757  * @id: the id string
758  * @device: the device index (zero based)
759  * @playback_count: the number of substreams for playback
760  * @capture_count: the number of substreams for capture
761  * @rpcm: the pointer to store the new pcm instance
762  *
763  * Creates a new PCM instance.
764  *
765  * The pcm operators have to be set afterwards to the new instance
766  * via snd_pcm_set_ops().
767  *
768  * Return: Zero if successful, or a negative error code on failure.
769  */
770 int snd_pcm_new(struct snd_card *card, const char *id, int device,
771 		int playback_count, int capture_count, struct snd_pcm **rpcm)
772 {
773 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
774 			false, rpcm);
775 }
776 EXPORT_SYMBOL(snd_pcm_new);
777 
778 /**
779  * snd_pcm_new_internal - create a new internal PCM instance
780  * @card: the card instance
781  * @id: the id string
782  * @device: the device index (zero based - shared with normal PCMs)
783  * @playback_count: the number of substreams for playback
784  * @capture_count: the number of substreams for capture
785  * @rpcm: the pointer to store the new pcm instance
786  *
787  * Creates a new internal PCM instance with no userspace device or procfs
788  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
789  * will only be used internally by kernel drivers. i.e. it cannot be opened
790  * by userspace. It provides existing ASoC components drivers with a substream
791  * and access to any private data.
792  *
793  * The pcm operators have to be set afterwards to the new instance
794  * via snd_pcm_set_ops().
795  *
796  * Return: Zero if successful, or a negative error code on failure.
797  */
798 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
799 	int playback_count, int capture_count,
800 	struct snd_pcm **rpcm)
801 {
802 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
803 			true, rpcm);
804 }
805 EXPORT_SYMBOL(snd_pcm_new_internal);
806 
807 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
808 {
809 	struct snd_pcm_substream *substream, *substream_next;
810 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
811 	struct snd_pcm_oss_setup *setup, *setupn;
812 #endif
813 	substream = pstr->substream;
814 	while (substream) {
815 		substream_next = substream->next;
816 		snd_pcm_timer_done(substream);
817 		snd_pcm_substream_proc_done(substream);
818 		kfree(substream);
819 		substream = substream_next;
820 	}
821 	snd_pcm_stream_proc_done(pstr);
822 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
823 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
824 		setupn = setup->next;
825 		kfree(setup->task_name);
826 		kfree(setup);
827 	}
828 #endif
829 }
830 
831 static int snd_pcm_free(struct snd_pcm *pcm)
832 {
833 	struct snd_pcm_notify *notify;
834 
835 	if (!pcm)
836 		return 0;
837 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
838 		notify->n_unregister(pcm);
839 	}
840 	if (pcm->private_free)
841 		pcm->private_free(pcm);
842 	snd_pcm_lib_preallocate_free_for_all(pcm);
843 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
844 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
845 	kfree(pcm);
846 	return 0;
847 }
848 
849 static int snd_pcm_dev_free(struct snd_device *device)
850 {
851 	struct snd_pcm *pcm = device->device_data;
852 	return snd_pcm_free(pcm);
853 }
854 
855 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
856 			     struct file *file,
857 			     struct snd_pcm_substream **rsubstream)
858 {
859 	struct snd_pcm_str * pstr;
860 	struct snd_pcm_substream *substream;
861 	struct snd_pcm_runtime *runtime;
862 	struct snd_ctl_file *kctl;
863 	struct snd_card *card;
864 	int prefer_subdevice = -1;
865 	size_t size;
866 
867 	if (snd_BUG_ON(!pcm || !rsubstream))
868 		return -ENXIO;
869 	*rsubstream = NULL;
870 	pstr = &pcm->streams[stream];
871 	if (pstr->substream == NULL || pstr->substream_count == 0)
872 		return -ENODEV;
873 
874 	card = pcm->card;
875 	read_lock(&card->ctl_files_rwlock);
876 	list_for_each_entry(kctl, &card->ctl_files, list) {
877 		if (kctl->pid == task_pid(current)) {
878 			prefer_subdevice = kctl->prefer_pcm_subdevice;
879 			if (prefer_subdevice != -1)
880 				break;
881 		}
882 	}
883 	read_unlock(&card->ctl_files_rwlock);
884 
885 	switch (stream) {
886 	case SNDRV_PCM_STREAM_PLAYBACK:
887 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
888 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
889 				if (SUBSTREAM_BUSY(substream))
890 					return -EAGAIN;
891 			}
892 		}
893 		break;
894 	case SNDRV_PCM_STREAM_CAPTURE:
895 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
896 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
897 				if (SUBSTREAM_BUSY(substream))
898 					return -EAGAIN;
899 			}
900 		}
901 		break;
902 	default:
903 		return -EINVAL;
904 	}
905 
906 	if (file->f_flags & O_APPEND) {
907 		if (prefer_subdevice < 0) {
908 			if (pstr->substream_count > 1)
909 				return -EINVAL; /* must be unique */
910 			substream = pstr->substream;
911 		} else {
912 			for (substream = pstr->substream; substream;
913 			     substream = substream->next)
914 				if (substream->number == prefer_subdevice)
915 					break;
916 		}
917 		if (! substream)
918 			return -ENODEV;
919 		if (! SUBSTREAM_BUSY(substream))
920 			return -EBADFD;
921 		substream->ref_count++;
922 		*rsubstream = substream;
923 		return 0;
924 	}
925 
926 	if (prefer_subdevice >= 0) {
927 		for (substream = pstr->substream; substream; substream = substream->next)
928 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
929 				goto __ok;
930 	}
931 	for (substream = pstr->substream; substream; substream = substream->next)
932 		if (!SUBSTREAM_BUSY(substream))
933 			break;
934       __ok:
935 	if (substream == NULL)
936 		return -EAGAIN;
937 
938 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
939 	if (runtime == NULL)
940 		return -ENOMEM;
941 
942 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
943 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
944 	if (runtime->status == NULL) {
945 		kfree(runtime);
946 		return -ENOMEM;
947 	}
948 	memset((void*)runtime->status, 0, size);
949 
950 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
951 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
952 	if (runtime->control == NULL) {
953 		snd_free_pages((void*)runtime->status,
954 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
955 		kfree(runtime);
956 		return -ENOMEM;
957 	}
958 	memset((void*)runtime->control, 0, size);
959 
960 	init_waitqueue_head(&runtime->sleep);
961 	init_waitqueue_head(&runtime->tsleep);
962 
963 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
964 
965 	substream->runtime = runtime;
966 	substream->private_data = pcm->private_data;
967 	substream->ref_count = 1;
968 	substream->f_flags = file->f_flags;
969 	substream->pid = get_pid(task_pid(current));
970 	pstr->substream_opened++;
971 	*rsubstream = substream;
972 	return 0;
973 }
974 
975 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
976 {
977 	struct snd_pcm_runtime *runtime;
978 
979 	if (PCM_RUNTIME_CHECK(substream))
980 		return;
981 	runtime = substream->runtime;
982 	if (runtime->private_free != NULL)
983 		runtime->private_free(runtime);
984 	snd_free_pages((void*)runtime->status,
985 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
986 	snd_free_pages((void*)runtime->control,
987 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
988 	kfree(runtime->hw_constraints.rules);
989 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
990 	kfree(runtime->hwptr_log);
991 #endif
992 	kfree(runtime);
993 	substream->runtime = NULL;
994 	put_pid(substream->pid);
995 	substream->pid = NULL;
996 	substream->pstr->substream_opened--;
997 }
998 
999 static ssize_t show_pcm_class(struct device *dev,
1000 			      struct device_attribute *attr, char *buf)
1001 {
1002 	struct snd_pcm *pcm;
1003 	const char *str;
1004 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1005 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
1006 		[SNDRV_PCM_CLASS_MULTI] = "multi",
1007 		[SNDRV_PCM_CLASS_MODEM] = "modem",
1008 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1009 	};
1010 
1011 	if (! (pcm = dev_get_drvdata(dev)) ||
1012 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1013 		str = "none";
1014 	else
1015 		str = strs[pcm->dev_class];
1016         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1017 }
1018 
1019 static struct device_attribute pcm_attrs =
1020 	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1021 
1022 static int snd_pcm_dev_register(struct snd_device *device)
1023 {
1024 	int cidx, err;
1025 	struct snd_pcm_substream *substream;
1026 	struct snd_pcm_notify *notify;
1027 	char str[16];
1028 	struct snd_pcm *pcm;
1029 	struct device *dev;
1030 
1031 	if (snd_BUG_ON(!device || !device->device_data))
1032 		return -ENXIO;
1033 	pcm = device->device_data;
1034 	mutex_lock(&register_mutex);
1035 	err = snd_pcm_add(pcm);
1036 	if (err) {
1037 		mutex_unlock(&register_mutex);
1038 		return err;
1039 	}
1040 	for (cidx = 0; cidx < 2; cidx++) {
1041 		int devtype = -1;
1042 		if (pcm->streams[cidx].substream == NULL || pcm->internal)
1043 			continue;
1044 		switch (cidx) {
1045 		case SNDRV_PCM_STREAM_PLAYBACK:
1046 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1047 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1048 			break;
1049 		case SNDRV_PCM_STREAM_CAPTURE:
1050 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1051 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1052 			break;
1053 		}
1054 		/* device pointer to use, pcm->dev takes precedence if
1055 		 * it is assigned, otherwise fall back to card's device
1056 		 * if possible */
1057 		dev = pcm->dev;
1058 		if (!dev)
1059 			dev = snd_card_get_device_link(pcm->card);
1060 		/* register pcm */
1061 		err = snd_register_device_for_dev(devtype, pcm->card,
1062 						  pcm->device,
1063 						  &snd_pcm_f_ops[cidx],
1064 						  pcm, str, dev);
1065 		if (err < 0) {
1066 			list_del(&pcm->list);
1067 			mutex_unlock(&register_mutex);
1068 			return err;
1069 		}
1070 		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,
1071 					  &pcm_attrs);
1072 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1073 			snd_pcm_timer_init(substream);
1074 	}
1075 
1076 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1077 		notify->n_register(pcm);
1078 
1079 	mutex_unlock(&register_mutex);
1080 	return 0;
1081 }
1082 
1083 static int snd_pcm_dev_disconnect(struct snd_device *device)
1084 {
1085 	struct snd_pcm *pcm = device->device_data;
1086 	struct snd_pcm_notify *notify;
1087 	struct snd_pcm_substream *substream;
1088 	int cidx, devtype;
1089 
1090 	mutex_lock(&register_mutex);
1091 	if (list_empty(&pcm->list))
1092 		goto unlock;
1093 
1094 	mutex_lock(&pcm->open_mutex);
1095 	wake_up(&pcm->open_wait);
1096 	list_del_init(&pcm->list);
1097 	for (cidx = 0; cidx < 2; cidx++)
1098 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1099 			snd_pcm_stream_lock_irq(substream);
1100 			if (substream->runtime) {
1101 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1102 				wake_up(&substream->runtime->sleep);
1103 				wake_up(&substream->runtime->tsleep);
1104 			}
1105 			snd_pcm_stream_unlock_irq(substream);
1106 		}
1107 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1108 		notify->n_disconnect(pcm);
1109 	}
1110 	for (cidx = 0; cidx < 2; cidx++) {
1111 		devtype = -1;
1112 		switch (cidx) {
1113 		case SNDRV_PCM_STREAM_PLAYBACK:
1114 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1115 			break;
1116 		case SNDRV_PCM_STREAM_CAPTURE:
1117 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1118 			break;
1119 		}
1120 		snd_unregister_device(devtype, pcm->card, pcm->device);
1121 		if (pcm->streams[cidx].chmap_kctl) {
1122 			snd_ctl_remove(pcm->card, pcm->streams[cidx].chmap_kctl);
1123 			pcm->streams[cidx].chmap_kctl = NULL;
1124 		}
1125 	}
1126 	mutex_unlock(&pcm->open_mutex);
1127  unlock:
1128 	mutex_unlock(&register_mutex);
1129 	return 0;
1130 }
1131 
1132 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1133 {
1134 	struct snd_pcm *pcm;
1135 
1136 	if (snd_BUG_ON(!notify ||
1137 		       !notify->n_register ||
1138 		       !notify->n_unregister ||
1139 		       !notify->n_disconnect))
1140 		return -EINVAL;
1141 	mutex_lock(&register_mutex);
1142 	if (nfree) {
1143 		list_del(&notify->list);
1144 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1145 			notify->n_unregister(pcm);
1146 	} else {
1147 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1148 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1149 			notify->n_register(pcm);
1150 	}
1151 	mutex_unlock(&register_mutex);
1152 	return 0;
1153 }
1154 
1155 EXPORT_SYMBOL(snd_pcm_notify);
1156 
1157 #ifdef CONFIG_PROC_FS
1158 /*
1159  *  Info interface
1160  */
1161 
1162 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1163 			      struct snd_info_buffer *buffer)
1164 {
1165 	struct snd_pcm *pcm;
1166 
1167 	mutex_lock(&register_mutex);
1168 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1169 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1170 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1171 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1172 			snd_iprintf(buffer, " : playback %i",
1173 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1174 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1175 			snd_iprintf(buffer, " : capture %i",
1176 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1177 		snd_iprintf(buffer, "\n");
1178 	}
1179 	mutex_unlock(&register_mutex);
1180 }
1181 
1182 static struct snd_info_entry *snd_pcm_proc_entry;
1183 
1184 static void snd_pcm_proc_init(void)
1185 {
1186 	struct snd_info_entry *entry;
1187 
1188 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1189 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1190 		if (snd_info_register(entry) < 0) {
1191 			snd_info_free_entry(entry);
1192 			entry = NULL;
1193 		}
1194 	}
1195 	snd_pcm_proc_entry = entry;
1196 }
1197 
1198 static void snd_pcm_proc_done(void)
1199 {
1200 	snd_info_free_entry(snd_pcm_proc_entry);
1201 }
1202 
1203 #else /* !CONFIG_PROC_FS */
1204 #define snd_pcm_proc_init()
1205 #define snd_pcm_proc_done()
1206 #endif /* CONFIG_PROC_FS */
1207 
1208 
1209 /*
1210  *  ENTRY functions
1211  */
1212 
1213 static int __init alsa_pcm_init(void)
1214 {
1215 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1216 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1217 	snd_pcm_proc_init();
1218 	return 0;
1219 }
1220 
1221 static void __exit alsa_pcm_exit(void)
1222 {
1223 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1224 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1225 	snd_pcm_proc_done();
1226 }
1227 
1228 module_init(alsa_pcm_init)
1229 module_exit(alsa_pcm_exit)
1230