xref: /openbmc/linux/sound/core/pcm.c (revision 6774def6)
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 	FORMAT(DSD_U32_LE),
219 };
220 
221 const char *snd_pcm_format_name(snd_pcm_format_t format)
222 {
223 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
224 		return "Unknown";
225 	return snd_pcm_format_names[(__force unsigned int)format];
226 }
227 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
228 
229 #ifdef CONFIG_SND_VERBOSE_PROCFS
230 
231 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
232 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
233 #define READY(v) [SNDRV_PCM_READY_##v] = #v
234 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
235 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
236 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
237 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
238 #define START(v) [SNDRV_PCM_START_##v] = #v
239 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
240 
241 static char *snd_pcm_stream_names[] = {
242 	STREAM(PLAYBACK),
243 	STREAM(CAPTURE),
244 };
245 
246 static char *snd_pcm_state_names[] = {
247 	STATE(OPEN),
248 	STATE(SETUP),
249 	STATE(PREPARED),
250 	STATE(RUNNING),
251 	STATE(XRUN),
252 	STATE(DRAINING),
253 	STATE(PAUSED),
254 	STATE(SUSPENDED),
255 };
256 
257 static char *snd_pcm_access_names[] = {
258 	ACCESS(MMAP_INTERLEAVED),
259 	ACCESS(MMAP_NONINTERLEAVED),
260 	ACCESS(MMAP_COMPLEX),
261 	ACCESS(RW_INTERLEAVED),
262 	ACCESS(RW_NONINTERLEAVED),
263 };
264 
265 static char *snd_pcm_subformat_names[] = {
266 	SUBFORMAT(STD),
267 };
268 
269 static char *snd_pcm_tstamp_mode_names[] = {
270 	TSTAMP(NONE),
271 	TSTAMP(ENABLE),
272 };
273 
274 static const char *snd_pcm_stream_name(int stream)
275 {
276 	return snd_pcm_stream_names[stream];
277 }
278 
279 static const char *snd_pcm_access_name(snd_pcm_access_t access)
280 {
281 	return snd_pcm_access_names[(__force int)access];
282 }
283 
284 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
285 {
286 	return snd_pcm_subformat_names[(__force int)subformat];
287 }
288 
289 static const char *snd_pcm_tstamp_mode_name(int mode)
290 {
291 	return snd_pcm_tstamp_mode_names[mode];
292 }
293 
294 static const char *snd_pcm_state_name(snd_pcm_state_t state)
295 {
296 	return snd_pcm_state_names[(__force int)state];
297 }
298 
299 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
300 #include <linux/soundcard.h>
301 
302 static const char *snd_pcm_oss_format_name(int format)
303 {
304 	switch (format) {
305 	case AFMT_MU_LAW:
306 		return "MU_LAW";
307 	case AFMT_A_LAW:
308 		return "A_LAW";
309 	case AFMT_IMA_ADPCM:
310 		return "IMA_ADPCM";
311 	case AFMT_U8:
312 		return "U8";
313 	case AFMT_S16_LE:
314 		return "S16_LE";
315 	case AFMT_S16_BE:
316 		return "S16_BE";
317 	case AFMT_S8:
318 		return "S8";
319 	case AFMT_U16_LE:
320 		return "U16_LE";
321 	case AFMT_U16_BE:
322 		return "U16_BE";
323 	case AFMT_MPEG:
324 		return "MPEG";
325 	default:
326 		return "unknown";
327 	}
328 }
329 #endif
330 
331 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
332 				   struct snd_info_buffer *buffer)
333 {
334 	struct snd_pcm_info *info;
335 	int err;
336 
337 	if (! substream)
338 		return;
339 
340 	info = kmalloc(sizeof(*info), GFP_KERNEL);
341 	if (! info) {
342 		pcm_dbg(substream->pcm,
343 			"snd_pcm_proc_info_read: cannot malloc\n");
344 		return;
345 	}
346 
347 	err = snd_pcm_info(substream, info);
348 	if (err < 0) {
349 		snd_iprintf(buffer, "error %d\n", err);
350 		kfree(info);
351 		return;
352 	}
353 	snd_iprintf(buffer, "card: %d\n", info->card);
354 	snd_iprintf(buffer, "device: %d\n", info->device);
355 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
356 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
357 	snd_iprintf(buffer, "id: %s\n", info->id);
358 	snd_iprintf(buffer, "name: %s\n", info->name);
359 	snd_iprintf(buffer, "subname: %s\n", info->subname);
360 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
361 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
362 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
363 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
364 	kfree(info);
365 }
366 
367 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
368 					  struct snd_info_buffer *buffer)
369 {
370 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
371 			       buffer);
372 }
373 
374 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
375 					     struct snd_info_buffer *buffer)
376 {
377 	snd_pcm_proc_info_read(entry->private_data, buffer);
378 }
379 
380 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
381 						  struct snd_info_buffer *buffer)
382 {
383 	struct snd_pcm_substream *substream = entry->private_data;
384 	struct snd_pcm_runtime *runtime;
385 
386 	mutex_lock(&substream->pcm->open_mutex);
387 	runtime = substream->runtime;
388 	if (!runtime) {
389 		snd_iprintf(buffer, "closed\n");
390 		goto unlock;
391 	}
392 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
393 		snd_iprintf(buffer, "no setup\n");
394 		goto unlock;
395 	}
396 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
397 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
398 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
399 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
400 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
401 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
402 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
403 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
404 	if (substream->oss.oss) {
405 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
406 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
407 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
408 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
409 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
410 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
411 	}
412 #endif
413  unlock:
414 	mutex_unlock(&substream->pcm->open_mutex);
415 }
416 
417 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
418 						  struct snd_info_buffer *buffer)
419 {
420 	struct snd_pcm_substream *substream = entry->private_data;
421 	struct snd_pcm_runtime *runtime;
422 
423 	mutex_lock(&substream->pcm->open_mutex);
424 	runtime = substream->runtime;
425 	if (!runtime) {
426 		snd_iprintf(buffer, "closed\n");
427 		goto unlock;
428 	}
429 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
430 		snd_iprintf(buffer, "no setup\n");
431 		goto unlock;
432 	}
433 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
434 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
435 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
436 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
437 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
438 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
439 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
440 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
441  unlock:
442 	mutex_unlock(&substream->pcm->open_mutex);
443 }
444 
445 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
446 					       struct snd_info_buffer *buffer)
447 {
448 	struct snd_pcm_substream *substream = entry->private_data;
449 	struct snd_pcm_runtime *runtime;
450 	struct snd_pcm_status status;
451 	int err;
452 
453 	mutex_lock(&substream->pcm->open_mutex);
454 	runtime = substream->runtime;
455 	if (!runtime) {
456 		snd_iprintf(buffer, "closed\n");
457 		goto unlock;
458 	}
459 	memset(&status, 0, sizeof(status));
460 	err = snd_pcm_status(substream, &status);
461 	if (err < 0) {
462 		snd_iprintf(buffer, "error %d\n", err);
463 		goto unlock;
464 	}
465 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
466 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
467 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
468 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
469 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
470 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
471 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
472 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
473 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
474 	snd_iprintf(buffer, "-----\n");
475 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
476 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
477  unlock:
478 	mutex_unlock(&substream->pcm->open_mutex);
479 }
480 
481 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
482 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
483 				    struct snd_info_buffer *buffer)
484 {
485 	struct snd_pcm_str *pstr = entry->private_data;
486 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
487 }
488 
489 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
490 				     struct snd_info_buffer *buffer)
491 {
492 	struct snd_pcm_str *pstr = entry->private_data;
493 	char line[64];
494 	if (!snd_info_get_line(buffer, line, sizeof(line)))
495 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
496 }
497 #endif
498 
499 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
500 {
501 	struct snd_pcm *pcm = pstr->pcm;
502 	struct snd_info_entry *entry;
503 	char name[16];
504 
505 	sprintf(name, "pcm%i%c", pcm->device,
506 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
507 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
508 		return -ENOMEM;
509 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
510 	if (snd_info_register(entry) < 0) {
511 		snd_info_free_entry(entry);
512 		return -ENOMEM;
513 	}
514 	pstr->proc_root = entry;
515 
516 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
517 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
518 		if (snd_info_register(entry) < 0) {
519 			snd_info_free_entry(entry);
520 			entry = NULL;
521 		}
522 	}
523 	pstr->proc_info_entry = entry;
524 
525 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
526 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
527 						pstr->proc_root)) != NULL) {
528 		entry->c.text.read = snd_pcm_xrun_debug_read;
529 		entry->c.text.write = snd_pcm_xrun_debug_write;
530 		entry->mode |= S_IWUSR;
531 		entry->private_data = pstr;
532 		if (snd_info_register(entry) < 0) {
533 			snd_info_free_entry(entry);
534 			entry = NULL;
535 		}
536 	}
537 	pstr->proc_xrun_debug_entry = entry;
538 #endif
539 	return 0;
540 }
541 
542 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
543 {
544 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
545 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
546 	pstr->proc_xrun_debug_entry = NULL;
547 #endif
548 	snd_info_free_entry(pstr->proc_info_entry);
549 	pstr->proc_info_entry = NULL;
550 	snd_info_free_entry(pstr->proc_root);
551 	pstr->proc_root = NULL;
552 	return 0;
553 }
554 
555 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
556 {
557 	struct snd_info_entry *entry;
558 	struct snd_card *card;
559 	char name[16];
560 
561 	card = substream->pcm->card;
562 
563 	sprintf(name, "sub%i", substream->number);
564 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
565 		return -ENOMEM;
566 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
567 	if (snd_info_register(entry) < 0) {
568 		snd_info_free_entry(entry);
569 		return -ENOMEM;
570 	}
571 	substream->proc_root = entry;
572 
573 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
574 		snd_info_set_text_ops(entry, substream,
575 				      snd_pcm_substream_proc_info_read);
576 		if (snd_info_register(entry) < 0) {
577 			snd_info_free_entry(entry);
578 			entry = NULL;
579 		}
580 	}
581 	substream->proc_info_entry = entry;
582 
583 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
584 		snd_info_set_text_ops(entry, substream,
585 				      snd_pcm_substream_proc_hw_params_read);
586 		if (snd_info_register(entry) < 0) {
587 			snd_info_free_entry(entry);
588 			entry = NULL;
589 		}
590 	}
591 	substream->proc_hw_params_entry = entry;
592 
593 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
594 		snd_info_set_text_ops(entry, substream,
595 				      snd_pcm_substream_proc_sw_params_read);
596 		if (snd_info_register(entry) < 0) {
597 			snd_info_free_entry(entry);
598 			entry = NULL;
599 		}
600 	}
601 	substream->proc_sw_params_entry = entry;
602 
603 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
604 		snd_info_set_text_ops(entry, substream,
605 				      snd_pcm_substream_proc_status_read);
606 		if (snd_info_register(entry) < 0) {
607 			snd_info_free_entry(entry);
608 			entry = NULL;
609 		}
610 	}
611 	substream->proc_status_entry = entry;
612 
613 	return 0;
614 }
615 
616 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
617 {
618 	snd_info_free_entry(substream->proc_info_entry);
619 	substream->proc_info_entry = NULL;
620 	snd_info_free_entry(substream->proc_hw_params_entry);
621 	substream->proc_hw_params_entry = NULL;
622 	snd_info_free_entry(substream->proc_sw_params_entry);
623 	substream->proc_sw_params_entry = NULL;
624 	snd_info_free_entry(substream->proc_status_entry);
625 	substream->proc_status_entry = NULL;
626 	snd_info_free_entry(substream->proc_root);
627 	substream->proc_root = NULL;
628 	return 0;
629 }
630 #else /* !CONFIG_SND_VERBOSE_PROCFS */
631 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
632 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
633 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
634 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
635 #endif /* CONFIG_SND_VERBOSE_PROCFS */
636 
637 /**
638  * snd_pcm_new_stream - create a new PCM stream
639  * @pcm: the pcm instance
640  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
641  * @substream_count: the number of substreams
642  *
643  * Creates a new stream for the pcm.
644  * The corresponding stream on the pcm must have been empty before
645  * calling this, i.e. zero must be given to the argument of
646  * snd_pcm_new().
647  *
648  * Return: Zero if successful, or a negative error code on failure.
649  */
650 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
651 {
652 	int idx, err;
653 	struct snd_pcm_str *pstr = &pcm->streams[stream];
654 	struct snd_pcm_substream *substream, *prev;
655 
656 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
657 	mutex_init(&pstr->oss.setup_mutex);
658 #endif
659 	pstr->stream = stream;
660 	pstr->pcm = pcm;
661 	pstr->substream_count = substream_count;
662 	if (substream_count > 0 && !pcm->internal) {
663 		err = snd_pcm_stream_proc_init(pstr);
664 		if (err < 0) {
665 			pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
666 			return err;
667 		}
668 	}
669 	prev = NULL;
670 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
671 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
672 		if (substream == NULL) {
673 			pcm_err(pcm, "Cannot allocate PCM substream\n");
674 			return -ENOMEM;
675 		}
676 		substream->pcm = pcm;
677 		substream->pstr = pstr;
678 		substream->number = idx;
679 		substream->stream = stream;
680 		sprintf(substream->name, "subdevice #%i", idx);
681 		substream->buffer_bytes_max = UINT_MAX;
682 		if (prev == NULL)
683 			pstr->substream = substream;
684 		else
685 			prev->next = substream;
686 
687 		if (!pcm->internal) {
688 			err = snd_pcm_substream_proc_init(substream);
689 			if (err < 0) {
690 				pcm_err(pcm,
691 					"Error in snd_pcm_stream_proc_init\n");
692 				if (prev == NULL)
693 					pstr->substream = NULL;
694 				else
695 					prev->next = NULL;
696 				kfree(substream);
697 				return err;
698 			}
699 		}
700 		substream->group = &substream->self_group;
701 		spin_lock_init(&substream->self_group.lock);
702 		mutex_init(&substream->self_group.mutex);
703 		INIT_LIST_HEAD(&substream->self_group.substreams);
704 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
705 		atomic_set(&substream->mmap_count, 0);
706 		prev = substream;
707 	}
708 	return 0;
709 }
710 
711 EXPORT_SYMBOL(snd_pcm_new_stream);
712 
713 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
714 		int playback_count, int capture_count, bool internal,
715 		struct snd_pcm **rpcm)
716 {
717 	struct snd_pcm *pcm;
718 	int err;
719 	static struct snd_device_ops ops = {
720 		.dev_free = snd_pcm_dev_free,
721 		.dev_register =	snd_pcm_dev_register,
722 		.dev_disconnect = snd_pcm_dev_disconnect,
723 	};
724 
725 	if (snd_BUG_ON(!card))
726 		return -ENXIO;
727 	if (rpcm)
728 		*rpcm = NULL;
729 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
730 	if (pcm == NULL) {
731 		dev_err(card->dev, "Cannot allocate PCM\n");
732 		return -ENOMEM;
733 	}
734 	pcm->card = card;
735 	pcm->device = device;
736 	pcm->internal = internal;
737 	if (id)
738 		strlcpy(pcm->id, id, sizeof(pcm->id));
739 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
740 		snd_pcm_free(pcm);
741 		return err;
742 	}
743 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
744 		snd_pcm_free(pcm);
745 		return err;
746 	}
747 	mutex_init(&pcm->open_mutex);
748 	init_waitqueue_head(&pcm->open_wait);
749 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
750 		snd_pcm_free(pcm);
751 		return err;
752 	}
753 	if (rpcm)
754 		*rpcm = pcm;
755 	return 0;
756 }
757 
758 /**
759  * snd_pcm_new - create a new PCM instance
760  * @card: the card instance
761  * @id: the id string
762  * @device: the device index (zero based)
763  * @playback_count: the number of substreams for playback
764  * @capture_count: the number of substreams for capture
765  * @rpcm: the pointer to store the new pcm instance
766  *
767  * Creates a new PCM instance.
768  *
769  * The pcm operators have to be set afterwards to the new instance
770  * via snd_pcm_set_ops().
771  *
772  * Return: Zero if successful, or a negative error code on failure.
773  */
774 int snd_pcm_new(struct snd_card *card, const char *id, int device,
775 		int playback_count, int capture_count, struct snd_pcm **rpcm)
776 {
777 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
778 			false, rpcm);
779 }
780 EXPORT_SYMBOL(snd_pcm_new);
781 
782 /**
783  * snd_pcm_new_internal - create a new internal PCM instance
784  * @card: the card instance
785  * @id: the id string
786  * @device: the device index (zero based - shared with normal PCMs)
787  * @playback_count: the number of substreams for playback
788  * @capture_count: the number of substreams for capture
789  * @rpcm: the pointer to store the new pcm instance
790  *
791  * Creates a new internal PCM instance with no userspace device or procfs
792  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
793  * will only be used internally by kernel drivers. i.e. it cannot be opened
794  * by userspace. It provides existing ASoC components drivers with a substream
795  * and access to any private data.
796  *
797  * The pcm operators have to be set afterwards to the new instance
798  * via snd_pcm_set_ops().
799  *
800  * Return: Zero if successful, or a negative error code on failure.
801  */
802 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
803 	int playback_count, int capture_count,
804 	struct snd_pcm **rpcm)
805 {
806 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
807 			true, rpcm);
808 }
809 EXPORT_SYMBOL(snd_pcm_new_internal);
810 
811 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
812 {
813 	struct snd_pcm_substream *substream, *substream_next;
814 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
815 	struct snd_pcm_oss_setup *setup, *setupn;
816 #endif
817 	substream = pstr->substream;
818 	while (substream) {
819 		substream_next = substream->next;
820 		snd_pcm_timer_done(substream);
821 		snd_pcm_substream_proc_done(substream);
822 		kfree(substream);
823 		substream = substream_next;
824 	}
825 	snd_pcm_stream_proc_done(pstr);
826 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
827 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
828 		setupn = setup->next;
829 		kfree(setup->task_name);
830 		kfree(setup);
831 	}
832 #endif
833 }
834 
835 static int snd_pcm_free(struct snd_pcm *pcm)
836 {
837 	struct snd_pcm_notify *notify;
838 
839 	if (!pcm)
840 		return 0;
841 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
842 		notify->n_unregister(pcm);
843 	}
844 	if (pcm->private_free)
845 		pcm->private_free(pcm);
846 	snd_pcm_lib_preallocate_free_for_all(pcm);
847 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
848 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
849 	kfree(pcm);
850 	return 0;
851 }
852 
853 static int snd_pcm_dev_free(struct snd_device *device)
854 {
855 	struct snd_pcm *pcm = device->device_data;
856 	return snd_pcm_free(pcm);
857 }
858 
859 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
860 			     struct file *file,
861 			     struct snd_pcm_substream **rsubstream)
862 {
863 	struct snd_pcm_str * pstr;
864 	struct snd_pcm_substream *substream;
865 	struct snd_pcm_runtime *runtime;
866 	struct snd_ctl_file *kctl;
867 	struct snd_card *card;
868 	int prefer_subdevice = -1;
869 	size_t size;
870 
871 	if (snd_BUG_ON(!pcm || !rsubstream))
872 		return -ENXIO;
873 	*rsubstream = NULL;
874 	pstr = &pcm->streams[stream];
875 	if (pstr->substream == NULL || pstr->substream_count == 0)
876 		return -ENODEV;
877 
878 	card = pcm->card;
879 	read_lock(&card->ctl_files_rwlock);
880 	list_for_each_entry(kctl, &card->ctl_files, list) {
881 		if (kctl->pid == task_pid(current)) {
882 			prefer_subdevice = kctl->prefer_pcm_subdevice;
883 			if (prefer_subdevice != -1)
884 				break;
885 		}
886 	}
887 	read_unlock(&card->ctl_files_rwlock);
888 
889 	switch (stream) {
890 	case SNDRV_PCM_STREAM_PLAYBACK:
891 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
892 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
893 				if (SUBSTREAM_BUSY(substream))
894 					return -EAGAIN;
895 			}
896 		}
897 		break;
898 	case SNDRV_PCM_STREAM_CAPTURE:
899 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
900 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
901 				if (SUBSTREAM_BUSY(substream))
902 					return -EAGAIN;
903 			}
904 		}
905 		break;
906 	default:
907 		return -EINVAL;
908 	}
909 
910 	if (file->f_flags & O_APPEND) {
911 		if (prefer_subdevice < 0) {
912 			if (pstr->substream_count > 1)
913 				return -EINVAL; /* must be unique */
914 			substream = pstr->substream;
915 		} else {
916 			for (substream = pstr->substream; substream;
917 			     substream = substream->next)
918 				if (substream->number == prefer_subdevice)
919 					break;
920 		}
921 		if (! substream)
922 			return -ENODEV;
923 		if (! SUBSTREAM_BUSY(substream))
924 			return -EBADFD;
925 		substream->ref_count++;
926 		*rsubstream = substream;
927 		return 0;
928 	}
929 
930 	if (prefer_subdevice >= 0) {
931 		for (substream = pstr->substream; substream; substream = substream->next)
932 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
933 				goto __ok;
934 	}
935 	for (substream = pstr->substream; substream; substream = substream->next)
936 		if (!SUBSTREAM_BUSY(substream))
937 			break;
938       __ok:
939 	if (substream == NULL)
940 		return -EAGAIN;
941 
942 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
943 	if (runtime == NULL)
944 		return -ENOMEM;
945 
946 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
947 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
948 	if (runtime->status == NULL) {
949 		kfree(runtime);
950 		return -ENOMEM;
951 	}
952 	memset((void*)runtime->status, 0, size);
953 
954 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
955 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
956 	if (runtime->control == NULL) {
957 		snd_free_pages((void*)runtime->status,
958 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
959 		kfree(runtime);
960 		return -ENOMEM;
961 	}
962 	memset((void*)runtime->control, 0, size);
963 
964 	init_waitqueue_head(&runtime->sleep);
965 	init_waitqueue_head(&runtime->tsleep);
966 
967 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
968 
969 	substream->runtime = runtime;
970 	substream->private_data = pcm->private_data;
971 	substream->ref_count = 1;
972 	substream->f_flags = file->f_flags;
973 	substream->pid = get_pid(task_pid(current));
974 	pstr->substream_opened++;
975 	*rsubstream = substream;
976 	return 0;
977 }
978 
979 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
980 {
981 	struct snd_pcm_runtime *runtime;
982 
983 	if (PCM_RUNTIME_CHECK(substream))
984 		return;
985 	runtime = substream->runtime;
986 	if (runtime->private_free != NULL)
987 		runtime->private_free(runtime);
988 	snd_free_pages((void*)runtime->status,
989 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
990 	snd_free_pages((void*)runtime->control,
991 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
992 	kfree(runtime->hw_constraints.rules);
993 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
994 	kfree(runtime->hwptr_log);
995 #endif
996 	kfree(runtime);
997 	substream->runtime = NULL;
998 	put_pid(substream->pid);
999 	substream->pid = NULL;
1000 	substream->pstr->substream_opened--;
1001 }
1002 
1003 static ssize_t show_pcm_class(struct device *dev,
1004 			      struct device_attribute *attr, char *buf)
1005 {
1006 	struct snd_pcm *pcm;
1007 	const char *str;
1008 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1009 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
1010 		[SNDRV_PCM_CLASS_MULTI] = "multi",
1011 		[SNDRV_PCM_CLASS_MODEM] = "modem",
1012 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1013 	};
1014 
1015 	if (! (pcm = dev_get_drvdata(dev)) ||
1016 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1017 		str = "none";
1018 	else
1019 		str = strs[pcm->dev_class];
1020         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1021 }
1022 
1023 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1024 static struct attribute *pcm_dev_attrs[] = {
1025 	&dev_attr_pcm_class.attr,
1026 	NULL
1027 };
1028 
1029 static struct attribute_group pcm_dev_attr_group = {
1030 	.attrs	= pcm_dev_attrs,
1031 };
1032 
1033 static const struct attribute_group *pcm_dev_attr_groups[] = {
1034 	&pcm_dev_attr_group,
1035 	NULL
1036 };
1037 
1038 static int snd_pcm_dev_register(struct snd_device *device)
1039 {
1040 	int cidx, err;
1041 	struct snd_pcm_substream *substream;
1042 	struct snd_pcm_notify *notify;
1043 	char str[16];
1044 	struct snd_pcm *pcm;
1045 	struct device *dev;
1046 
1047 	if (snd_BUG_ON(!device || !device->device_data))
1048 		return -ENXIO;
1049 	pcm = device->device_data;
1050 	mutex_lock(&register_mutex);
1051 	err = snd_pcm_add(pcm);
1052 	if (err) {
1053 		mutex_unlock(&register_mutex);
1054 		return err;
1055 	}
1056 	for (cidx = 0; cidx < 2; cidx++) {
1057 		int devtype = -1;
1058 		if (pcm->streams[cidx].substream == NULL || pcm->internal)
1059 			continue;
1060 		switch (cidx) {
1061 		case SNDRV_PCM_STREAM_PLAYBACK:
1062 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1063 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1064 			break;
1065 		case SNDRV_PCM_STREAM_CAPTURE:
1066 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1067 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1068 			break;
1069 		}
1070 		/* device pointer to use, pcm->dev takes precedence if
1071 		 * it is assigned, otherwise fall back to card's device
1072 		 * if possible */
1073 		dev = pcm->dev;
1074 		if (!dev)
1075 			dev = snd_card_get_device_link(pcm->card);
1076 		/* register pcm */
1077 		err = snd_register_device_for_dev(devtype, pcm->card,
1078 						  pcm->device,
1079 						  &snd_pcm_f_ops[cidx],
1080 						  pcm, str, dev);
1081 		if (err < 0) {
1082 			list_del(&pcm->list);
1083 			mutex_unlock(&register_mutex);
1084 			return err;
1085 		}
1086 
1087 		dev = snd_get_device(devtype, pcm->card, pcm->device);
1088 		if (dev) {
1089 			err = sysfs_create_groups(&dev->kobj,
1090 						  pcm_dev_attr_groups);
1091 			if (err < 0)
1092 				dev_warn(dev,
1093 					 "pcm %d:%d: cannot create sysfs groups\n",
1094 					 pcm->card->number, pcm->device);
1095 			put_device(dev);
1096 		}
1097 
1098 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1099 			snd_pcm_timer_init(substream);
1100 	}
1101 
1102 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1103 		notify->n_register(pcm);
1104 
1105 	mutex_unlock(&register_mutex);
1106 	return 0;
1107 }
1108 
1109 static int snd_pcm_dev_disconnect(struct snd_device *device)
1110 {
1111 	struct snd_pcm *pcm = device->device_data;
1112 	struct snd_pcm_notify *notify;
1113 	struct snd_pcm_substream *substream;
1114 	int cidx, devtype;
1115 
1116 	mutex_lock(&register_mutex);
1117 	if (list_empty(&pcm->list))
1118 		goto unlock;
1119 
1120 	mutex_lock(&pcm->open_mutex);
1121 	wake_up(&pcm->open_wait);
1122 	list_del_init(&pcm->list);
1123 	for (cidx = 0; cidx < 2; cidx++)
1124 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1125 			snd_pcm_stream_lock_irq(substream);
1126 			if (substream->runtime) {
1127 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1128 				wake_up(&substream->runtime->sleep);
1129 				wake_up(&substream->runtime->tsleep);
1130 			}
1131 			snd_pcm_stream_unlock_irq(substream);
1132 		}
1133 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1134 		notify->n_disconnect(pcm);
1135 	}
1136 	for (cidx = 0; cidx < 2; cidx++) {
1137 		devtype = -1;
1138 		switch (cidx) {
1139 		case SNDRV_PCM_STREAM_PLAYBACK:
1140 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1141 			break;
1142 		case SNDRV_PCM_STREAM_CAPTURE:
1143 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1144 			break;
1145 		}
1146 		snd_unregister_device(devtype, pcm->card, pcm->device);
1147 		if (pcm->streams[cidx].chmap_kctl) {
1148 			snd_ctl_remove(pcm->card, pcm->streams[cidx].chmap_kctl);
1149 			pcm->streams[cidx].chmap_kctl = NULL;
1150 		}
1151 	}
1152 	mutex_unlock(&pcm->open_mutex);
1153  unlock:
1154 	mutex_unlock(&register_mutex);
1155 	return 0;
1156 }
1157 
1158 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1159 {
1160 	struct snd_pcm *pcm;
1161 
1162 	if (snd_BUG_ON(!notify ||
1163 		       !notify->n_register ||
1164 		       !notify->n_unregister ||
1165 		       !notify->n_disconnect))
1166 		return -EINVAL;
1167 	mutex_lock(&register_mutex);
1168 	if (nfree) {
1169 		list_del(&notify->list);
1170 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1171 			notify->n_unregister(pcm);
1172 	} else {
1173 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1174 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1175 			notify->n_register(pcm);
1176 	}
1177 	mutex_unlock(&register_mutex);
1178 	return 0;
1179 }
1180 
1181 EXPORT_SYMBOL(snd_pcm_notify);
1182 
1183 #ifdef CONFIG_PROC_FS
1184 /*
1185  *  Info interface
1186  */
1187 
1188 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1189 			      struct snd_info_buffer *buffer)
1190 {
1191 	struct snd_pcm *pcm;
1192 
1193 	mutex_lock(&register_mutex);
1194 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1195 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1196 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1197 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1198 			snd_iprintf(buffer, " : playback %i",
1199 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1200 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1201 			snd_iprintf(buffer, " : capture %i",
1202 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1203 		snd_iprintf(buffer, "\n");
1204 	}
1205 	mutex_unlock(&register_mutex);
1206 }
1207 
1208 static struct snd_info_entry *snd_pcm_proc_entry;
1209 
1210 static void snd_pcm_proc_init(void)
1211 {
1212 	struct snd_info_entry *entry;
1213 
1214 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1215 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1216 		if (snd_info_register(entry) < 0) {
1217 			snd_info_free_entry(entry);
1218 			entry = NULL;
1219 		}
1220 	}
1221 	snd_pcm_proc_entry = entry;
1222 }
1223 
1224 static void snd_pcm_proc_done(void)
1225 {
1226 	snd_info_free_entry(snd_pcm_proc_entry);
1227 }
1228 
1229 #else /* !CONFIG_PROC_FS */
1230 #define snd_pcm_proc_init()
1231 #define snd_pcm_proc_done()
1232 #endif /* CONFIG_PROC_FS */
1233 
1234 
1235 /*
1236  *  ENTRY functions
1237  */
1238 
1239 static int __init alsa_pcm_init(void)
1240 {
1241 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1242 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1243 	snd_pcm_proc_init();
1244 	return 0;
1245 }
1246 
1247 static void __exit alsa_pcm_exit(void)
1248 {
1249 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1250 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1251 	snd_pcm_proc_done();
1252 }
1253 
1254 module_init(alsa_pcm_init)
1255 module_exit(alsa_pcm_exit)
1256