xref: /linux/sound/core/pcm.c (revision 2d7ce0e8a704d1aedc4462817a4eade1c3b00fbe)
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 	FORMAT(DSD_U16_BE),
220 	FORMAT(DSD_U32_BE),
221 };
222 
223 const char *snd_pcm_format_name(snd_pcm_format_t format)
224 {
225 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
226 		return "Unknown";
227 	return snd_pcm_format_names[(__force unsigned int)format];
228 }
229 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
230 
231 #ifdef CONFIG_SND_VERBOSE_PROCFS
232 
233 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
234 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
235 #define READY(v) [SNDRV_PCM_READY_##v] = #v
236 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
237 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
238 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
239 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
240 #define START(v) [SNDRV_PCM_START_##v] = #v
241 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
242 
243 static char *snd_pcm_stream_names[] = {
244 	STREAM(PLAYBACK),
245 	STREAM(CAPTURE),
246 };
247 
248 static char *snd_pcm_state_names[] = {
249 	STATE(OPEN),
250 	STATE(SETUP),
251 	STATE(PREPARED),
252 	STATE(RUNNING),
253 	STATE(XRUN),
254 	STATE(DRAINING),
255 	STATE(PAUSED),
256 	STATE(SUSPENDED),
257 };
258 
259 static char *snd_pcm_access_names[] = {
260 	ACCESS(MMAP_INTERLEAVED),
261 	ACCESS(MMAP_NONINTERLEAVED),
262 	ACCESS(MMAP_COMPLEX),
263 	ACCESS(RW_INTERLEAVED),
264 	ACCESS(RW_NONINTERLEAVED),
265 };
266 
267 static char *snd_pcm_subformat_names[] = {
268 	SUBFORMAT(STD),
269 };
270 
271 static char *snd_pcm_tstamp_mode_names[] = {
272 	TSTAMP(NONE),
273 	TSTAMP(ENABLE),
274 };
275 
276 static const char *snd_pcm_stream_name(int stream)
277 {
278 	return snd_pcm_stream_names[stream];
279 }
280 
281 static const char *snd_pcm_access_name(snd_pcm_access_t access)
282 {
283 	return snd_pcm_access_names[(__force int)access];
284 }
285 
286 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
287 {
288 	return snd_pcm_subformat_names[(__force int)subformat];
289 }
290 
291 static const char *snd_pcm_tstamp_mode_name(int mode)
292 {
293 	return snd_pcm_tstamp_mode_names[mode];
294 }
295 
296 static const char *snd_pcm_state_name(snd_pcm_state_t state)
297 {
298 	return snd_pcm_state_names[(__force int)state];
299 }
300 
301 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
302 #include <linux/soundcard.h>
303 
304 static const char *snd_pcm_oss_format_name(int format)
305 {
306 	switch (format) {
307 	case AFMT_MU_LAW:
308 		return "MU_LAW";
309 	case AFMT_A_LAW:
310 		return "A_LAW";
311 	case AFMT_IMA_ADPCM:
312 		return "IMA_ADPCM";
313 	case AFMT_U8:
314 		return "U8";
315 	case AFMT_S16_LE:
316 		return "S16_LE";
317 	case AFMT_S16_BE:
318 		return "S16_BE";
319 	case AFMT_S8:
320 		return "S8";
321 	case AFMT_U16_LE:
322 		return "U16_LE";
323 	case AFMT_U16_BE:
324 		return "U16_BE";
325 	case AFMT_MPEG:
326 		return "MPEG";
327 	default:
328 		return "unknown";
329 	}
330 }
331 #endif
332 
333 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
334 				   struct snd_info_buffer *buffer)
335 {
336 	struct snd_pcm_info *info;
337 	int err;
338 
339 	if (! substream)
340 		return;
341 
342 	info = kmalloc(sizeof(*info), GFP_KERNEL);
343 	if (! info) {
344 		pcm_dbg(substream->pcm,
345 			"snd_pcm_proc_info_read: cannot malloc\n");
346 		return;
347 	}
348 
349 	err = snd_pcm_info(substream, info);
350 	if (err < 0) {
351 		snd_iprintf(buffer, "error %d\n", err);
352 		kfree(info);
353 		return;
354 	}
355 	snd_iprintf(buffer, "card: %d\n", info->card);
356 	snd_iprintf(buffer, "device: %d\n", info->device);
357 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
358 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
359 	snd_iprintf(buffer, "id: %s\n", info->id);
360 	snd_iprintf(buffer, "name: %s\n", info->name);
361 	snd_iprintf(buffer, "subname: %s\n", info->subname);
362 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
363 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
364 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
365 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
366 	kfree(info);
367 }
368 
369 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
370 					  struct snd_info_buffer *buffer)
371 {
372 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
373 			       buffer);
374 }
375 
376 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
377 					     struct snd_info_buffer *buffer)
378 {
379 	snd_pcm_proc_info_read(entry->private_data, buffer);
380 }
381 
382 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
383 						  struct snd_info_buffer *buffer)
384 {
385 	struct snd_pcm_substream *substream = entry->private_data;
386 	struct snd_pcm_runtime *runtime;
387 
388 	mutex_lock(&substream->pcm->open_mutex);
389 	runtime = substream->runtime;
390 	if (!runtime) {
391 		snd_iprintf(buffer, "closed\n");
392 		goto unlock;
393 	}
394 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
395 		snd_iprintf(buffer, "no setup\n");
396 		goto unlock;
397 	}
398 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
399 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
400 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
401 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
402 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
403 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
404 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
405 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
406 	if (substream->oss.oss) {
407 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
408 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
409 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
410 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
411 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
412 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
413 	}
414 #endif
415  unlock:
416 	mutex_unlock(&substream->pcm->open_mutex);
417 }
418 
419 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
420 						  struct snd_info_buffer *buffer)
421 {
422 	struct snd_pcm_substream *substream = entry->private_data;
423 	struct snd_pcm_runtime *runtime;
424 
425 	mutex_lock(&substream->pcm->open_mutex);
426 	runtime = substream->runtime;
427 	if (!runtime) {
428 		snd_iprintf(buffer, "closed\n");
429 		goto unlock;
430 	}
431 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
432 		snd_iprintf(buffer, "no setup\n");
433 		goto unlock;
434 	}
435 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
436 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
437 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
438 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
439 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
440 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
441 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
442 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
443  unlock:
444 	mutex_unlock(&substream->pcm->open_mutex);
445 }
446 
447 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
448 					       struct snd_info_buffer *buffer)
449 {
450 	struct snd_pcm_substream *substream = entry->private_data;
451 	struct snd_pcm_runtime *runtime;
452 	struct snd_pcm_status status;
453 	int err;
454 
455 	mutex_lock(&substream->pcm->open_mutex);
456 	runtime = substream->runtime;
457 	if (!runtime) {
458 		snd_iprintf(buffer, "closed\n");
459 		goto unlock;
460 	}
461 	memset(&status, 0, sizeof(status));
462 	err = snd_pcm_status(substream, &status);
463 	if (err < 0) {
464 		snd_iprintf(buffer, "error %d\n", err);
465 		goto unlock;
466 	}
467 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
468 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
469 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
470 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
471 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
472 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
473 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
474 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
475 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
476 	snd_iprintf(buffer, "-----\n");
477 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
478 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
479  unlock:
480 	mutex_unlock(&substream->pcm->open_mutex);
481 }
482 
483 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
484 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
485 				    struct snd_info_buffer *buffer)
486 {
487 	struct snd_pcm_str *pstr = entry->private_data;
488 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
489 }
490 
491 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
492 				     struct snd_info_buffer *buffer)
493 {
494 	struct snd_pcm_str *pstr = entry->private_data;
495 	char line[64];
496 	if (!snd_info_get_line(buffer, line, sizeof(line)))
497 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
498 }
499 #endif
500 
501 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
502 {
503 	struct snd_pcm *pcm = pstr->pcm;
504 	struct snd_info_entry *entry;
505 	char name[16];
506 
507 	sprintf(name, "pcm%i%c", pcm->device,
508 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
509 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
510 		return -ENOMEM;
511 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
512 	if (snd_info_register(entry) < 0) {
513 		snd_info_free_entry(entry);
514 		return -ENOMEM;
515 	}
516 	pstr->proc_root = entry;
517 
518 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
519 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
520 		if (snd_info_register(entry) < 0) {
521 			snd_info_free_entry(entry);
522 			entry = NULL;
523 		}
524 	}
525 	pstr->proc_info_entry = entry;
526 
527 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
528 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
529 						pstr->proc_root)) != NULL) {
530 		entry->c.text.read = snd_pcm_xrun_debug_read;
531 		entry->c.text.write = snd_pcm_xrun_debug_write;
532 		entry->mode |= S_IWUSR;
533 		entry->private_data = pstr;
534 		if (snd_info_register(entry) < 0) {
535 			snd_info_free_entry(entry);
536 			entry = NULL;
537 		}
538 	}
539 	pstr->proc_xrun_debug_entry = entry;
540 #endif
541 	return 0;
542 }
543 
544 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
545 {
546 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
547 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
548 	pstr->proc_xrun_debug_entry = NULL;
549 #endif
550 	snd_info_free_entry(pstr->proc_info_entry);
551 	pstr->proc_info_entry = NULL;
552 	snd_info_free_entry(pstr->proc_root);
553 	pstr->proc_root = NULL;
554 	return 0;
555 }
556 
557 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
558 {
559 	struct snd_info_entry *entry;
560 	struct snd_card *card;
561 	char name[16];
562 
563 	card = substream->pcm->card;
564 
565 	sprintf(name, "sub%i", substream->number);
566 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
567 		return -ENOMEM;
568 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
569 	if (snd_info_register(entry) < 0) {
570 		snd_info_free_entry(entry);
571 		return -ENOMEM;
572 	}
573 	substream->proc_root = entry;
574 
575 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
576 		snd_info_set_text_ops(entry, substream,
577 				      snd_pcm_substream_proc_info_read);
578 		if (snd_info_register(entry) < 0) {
579 			snd_info_free_entry(entry);
580 			entry = NULL;
581 		}
582 	}
583 	substream->proc_info_entry = entry;
584 
585 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
586 		snd_info_set_text_ops(entry, substream,
587 				      snd_pcm_substream_proc_hw_params_read);
588 		if (snd_info_register(entry) < 0) {
589 			snd_info_free_entry(entry);
590 			entry = NULL;
591 		}
592 	}
593 	substream->proc_hw_params_entry = entry;
594 
595 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
596 		snd_info_set_text_ops(entry, substream,
597 				      snd_pcm_substream_proc_sw_params_read);
598 		if (snd_info_register(entry) < 0) {
599 			snd_info_free_entry(entry);
600 			entry = NULL;
601 		}
602 	}
603 	substream->proc_sw_params_entry = entry;
604 
605 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
606 		snd_info_set_text_ops(entry, substream,
607 				      snd_pcm_substream_proc_status_read);
608 		if (snd_info_register(entry) < 0) {
609 			snd_info_free_entry(entry);
610 			entry = NULL;
611 		}
612 	}
613 	substream->proc_status_entry = entry;
614 
615 	return 0;
616 }
617 
618 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
619 {
620 	snd_info_free_entry(substream->proc_info_entry);
621 	substream->proc_info_entry = NULL;
622 	snd_info_free_entry(substream->proc_hw_params_entry);
623 	substream->proc_hw_params_entry = NULL;
624 	snd_info_free_entry(substream->proc_sw_params_entry);
625 	substream->proc_sw_params_entry = NULL;
626 	snd_info_free_entry(substream->proc_status_entry);
627 	substream->proc_status_entry = NULL;
628 	snd_info_free_entry(substream->proc_root);
629 	substream->proc_root = NULL;
630 	return 0;
631 }
632 #else /* !CONFIG_SND_VERBOSE_PROCFS */
633 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
634 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
635 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
636 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
637 #endif /* CONFIG_SND_VERBOSE_PROCFS */
638 
639 /**
640  * snd_pcm_new_stream - create a new PCM stream
641  * @pcm: the pcm instance
642  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
643  * @substream_count: the number of substreams
644  *
645  * Creates a new stream for the pcm.
646  * The corresponding stream on the pcm must have been empty before
647  * calling this, i.e. zero must be given to the argument of
648  * snd_pcm_new().
649  *
650  * Return: Zero if successful, or a negative error code on failure.
651  */
652 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
653 {
654 	int idx, err;
655 	struct snd_pcm_str *pstr = &pcm->streams[stream];
656 	struct snd_pcm_substream *substream, *prev;
657 
658 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
659 	mutex_init(&pstr->oss.setup_mutex);
660 #endif
661 	pstr->stream = stream;
662 	pstr->pcm = pcm;
663 	pstr->substream_count = substream_count;
664 	if (substream_count > 0 && !pcm->internal) {
665 		err = snd_pcm_stream_proc_init(pstr);
666 		if (err < 0) {
667 			pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
668 			return err;
669 		}
670 	}
671 	prev = NULL;
672 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
673 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
674 		if (substream == NULL) {
675 			pcm_err(pcm, "Cannot allocate PCM substream\n");
676 			return -ENOMEM;
677 		}
678 		substream->pcm = pcm;
679 		substream->pstr = pstr;
680 		substream->number = idx;
681 		substream->stream = stream;
682 		sprintf(substream->name, "subdevice #%i", idx);
683 		substream->buffer_bytes_max = UINT_MAX;
684 		if (prev == NULL)
685 			pstr->substream = substream;
686 		else
687 			prev->next = substream;
688 
689 		if (!pcm->internal) {
690 			err = snd_pcm_substream_proc_init(substream);
691 			if (err < 0) {
692 				pcm_err(pcm,
693 					"Error in snd_pcm_stream_proc_init\n");
694 				if (prev == NULL)
695 					pstr->substream = NULL;
696 				else
697 					prev->next = NULL;
698 				kfree(substream);
699 				return err;
700 			}
701 		}
702 		substream->group = &substream->self_group;
703 		spin_lock_init(&substream->self_group.lock);
704 		mutex_init(&substream->self_group.mutex);
705 		INIT_LIST_HEAD(&substream->self_group.substreams);
706 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
707 		atomic_set(&substream->mmap_count, 0);
708 		prev = substream;
709 	}
710 	return 0;
711 }
712 
713 EXPORT_SYMBOL(snd_pcm_new_stream);
714 
715 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
716 		int playback_count, int capture_count, bool internal,
717 		struct snd_pcm **rpcm)
718 {
719 	struct snd_pcm *pcm;
720 	int err;
721 	static struct snd_device_ops ops = {
722 		.dev_free = snd_pcm_dev_free,
723 		.dev_register =	snd_pcm_dev_register,
724 		.dev_disconnect = snd_pcm_dev_disconnect,
725 	};
726 
727 	if (snd_BUG_ON(!card))
728 		return -ENXIO;
729 	if (rpcm)
730 		*rpcm = NULL;
731 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
732 	if (pcm == NULL) {
733 		dev_err(card->dev, "Cannot allocate PCM\n");
734 		return -ENOMEM;
735 	}
736 	pcm->card = card;
737 	pcm->device = device;
738 	pcm->internal = internal;
739 	if (id)
740 		strlcpy(pcm->id, id, sizeof(pcm->id));
741 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
742 		snd_pcm_free(pcm);
743 		return err;
744 	}
745 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
746 		snd_pcm_free(pcm);
747 		return err;
748 	}
749 	mutex_init(&pcm->open_mutex);
750 	init_waitqueue_head(&pcm->open_wait);
751 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
752 		snd_pcm_free(pcm);
753 		return err;
754 	}
755 	if (rpcm)
756 		*rpcm = pcm;
757 	return 0;
758 }
759 
760 /**
761  * snd_pcm_new - create a new PCM instance
762  * @card: the card instance
763  * @id: the id string
764  * @device: the device index (zero based)
765  * @playback_count: the number of substreams for playback
766  * @capture_count: the number of substreams for capture
767  * @rpcm: the pointer to store the new pcm instance
768  *
769  * Creates a new PCM instance.
770  *
771  * The pcm operators have to be set afterwards to the new instance
772  * via snd_pcm_set_ops().
773  *
774  * Return: Zero if successful, or a negative error code on failure.
775  */
776 int snd_pcm_new(struct snd_card *card, const char *id, int device,
777 		int playback_count, int capture_count, struct snd_pcm **rpcm)
778 {
779 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
780 			false, rpcm);
781 }
782 EXPORT_SYMBOL(snd_pcm_new);
783 
784 /**
785  * snd_pcm_new_internal - create a new internal PCM instance
786  * @card: the card instance
787  * @id: the id string
788  * @device: the device index (zero based - shared with normal PCMs)
789  * @playback_count: the number of substreams for playback
790  * @capture_count: the number of substreams for capture
791  * @rpcm: the pointer to store the new pcm instance
792  *
793  * Creates a new internal PCM instance with no userspace device or procfs
794  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
795  * will only be used internally by kernel drivers. i.e. it cannot be opened
796  * by userspace. It provides existing ASoC components drivers with a substream
797  * and access to any private data.
798  *
799  * The pcm operators have to be set afterwards to the new instance
800  * via snd_pcm_set_ops().
801  *
802  * Return: Zero if successful, or a negative error code on failure.
803  */
804 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
805 	int playback_count, int capture_count,
806 	struct snd_pcm **rpcm)
807 {
808 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
809 			true, rpcm);
810 }
811 EXPORT_SYMBOL(snd_pcm_new_internal);
812 
813 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
814 {
815 	struct snd_pcm_substream *substream, *substream_next;
816 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
817 	struct snd_pcm_oss_setup *setup, *setupn;
818 #endif
819 	substream = pstr->substream;
820 	while (substream) {
821 		substream_next = substream->next;
822 		snd_pcm_timer_done(substream);
823 		snd_pcm_substream_proc_done(substream);
824 		kfree(substream);
825 		substream = substream_next;
826 	}
827 	snd_pcm_stream_proc_done(pstr);
828 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
829 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
830 		setupn = setup->next;
831 		kfree(setup->task_name);
832 		kfree(setup);
833 	}
834 #endif
835 }
836 
837 static int snd_pcm_free(struct snd_pcm *pcm)
838 {
839 	struct snd_pcm_notify *notify;
840 
841 	if (!pcm)
842 		return 0;
843 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
844 		notify->n_unregister(pcm);
845 	}
846 	if (pcm->private_free)
847 		pcm->private_free(pcm);
848 	snd_pcm_lib_preallocate_free_for_all(pcm);
849 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
850 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
851 	kfree(pcm);
852 	return 0;
853 }
854 
855 static int snd_pcm_dev_free(struct snd_device *device)
856 {
857 	struct snd_pcm *pcm = device->device_data;
858 	return snd_pcm_free(pcm);
859 }
860 
861 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
862 			     struct file *file,
863 			     struct snd_pcm_substream **rsubstream)
864 {
865 	struct snd_pcm_str * pstr;
866 	struct snd_pcm_substream *substream;
867 	struct snd_pcm_runtime *runtime;
868 	struct snd_ctl_file *kctl;
869 	struct snd_card *card;
870 	int prefer_subdevice = -1;
871 	size_t size;
872 
873 	if (snd_BUG_ON(!pcm || !rsubstream))
874 		return -ENXIO;
875 	*rsubstream = NULL;
876 	pstr = &pcm->streams[stream];
877 	if (pstr->substream == NULL || pstr->substream_count == 0)
878 		return -ENODEV;
879 
880 	card = pcm->card;
881 	read_lock(&card->ctl_files_rwlock);
882 	list_for_each_entry(kctl, &card->ctl_files, list) {
883 		if (kctl->pid == task_pid(current)) {
884 			prefer_subdevice = kctl->prefer_pcm_subdevice;
885 			if (prefer_subdevice != -1)
886 				break;
887 		}
888 	}
889 	read_unlock(&card->ctl_files_rwlock);
890 
891 	switch (stream) {
892 	case SNDRV_PCM_STREAM_PLAYBACK:
893 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
894 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
895 				if (SUBSTREAM_BUSY(substream))
896 					return -EAGAIN;
897 			}
898 		}
899 		break;
900 	case SNDRV_PCM_STREAM_CAPTURE:
901 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
902 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
903 				if (SUBSTREAM_BUSY(substream))
904 					return -EAGAIN;
905 			}
906 		}
907 		break;
908 	default:
909 		return -EINVAL;
910 	}
911 
912 	if (file->f_flags & O_APPEND) {
913 		if (prefer_subdevice < 0) {
914 			if (pstr->substream_count > 1)
915 				return -EINVAL; /* must be unique */
916 			substream = pstr->substream;
917 		} else {
918 			for (substream = pstr->substream; substream;
919 			     substream = substream->next)
920 				if (substream->number == prefer_subdevice)
921 					break;
922 		}
923 		if (! substream)
924 			return -ENODEV;
925 		if (! SUBSTREAM_BUSY(substream))
926 			return -EBADFD;
927 		substream->ref_count++;
928 		*rsubstream = substream;
929 		return 0;
930 	}
931 
932 	if (prefer_subdevice >= 0) {
933 		for (substream = pstr->substream; substream; substream = substream->next)
934 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
935 				goto __ok;
936 	}
937 	for (substream = pstr->substream; substream; substream = substream->next)
938 		if (!SUBSTREAM_BUSY(substream))
939 			break;
940       __ok:
941 	if (substream == NULL)
942 		return -EAGAIN;
943 
944 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
945 	if (runtime == NULL)
946 		return -ENOMEM;
947 
948 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
949 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
950 	if (runtime->status == NULL) {
951 		kfree(runtime);
952 		return -ENOMEM;
953 	}
954 	memset((void*)runtime->status, 0, size);
955 
956 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
957 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
958 	if (runtime->control == NULL) {
959 		snd_free_pages((void*)runtime->status,
960 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
961 		kfree(runtime);
962 		return -ENOMEM;
963 	}
964 	memset((void*)runtime->control, 0, size);
965 
966 	init_waitqueue_head(&runtime->sleep);
967 	init_waitqueue_head(&runtime->tsleep);
968 
969 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
970 
971 	substream->runtime = runtime;
972 	substream->private_data = pcm->private_data;
973 	substream->ref_count = 1;
974 	substream->f_flags = file->f_flags;
975 	substream->pid = get_pid(task_pid(current));
976 	pstr->substream_opened++;
977 	*rsubstream = substream;
978 	return 0;
979 }
980 
981 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
982 {
983 	struct snd_pcm_runtime *runtime;
984 
985 	if (PCM_RUNTIME_CHECK(substream))
986 		return;
987 	runtime = substream->runtime;
988 	if (runtime->private_free != NULL)
989 		runtime->private_free(runtime);
990 	snd_free_pages((void*)runtime->status,
991 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
992 	snd_free_pages((void*)runtime->control,
993 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
994 	kfree(runtime->hw_constraints.rules);
995 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
996 	kfree(runtime->hwptr_log);
997 #endif
998 	kfree(runtime);
999 	substream->runtime = NULL;
1000 	put_pid(substream->pid);
1001 	substream->pid = NULL;
1002 	substream->pstr->substream_opened--;
1003 }
1004 
1005 static ssize_t show_pcm_class(struct device *dev,
1006 			      struct device_attribute *attr, char *buf)
1007 {
1008 	struct snd_pcm *pcm;
1009 	const char *str;
1010 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1011 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
1012 		[SNDRV_PCM_CLASS_MULTI] = "multi",
1013 		[SNDRV_PCM_CLASS_MODEM] = "modem",
1014 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1015 	};
1016 
1017 	if (! (pcm = dev_get_drvdata(dev)) ||
1018 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1019 		str = "none";
1020 	else
1021 		str = strs[pcm->dev_class];
1022         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1023 }
1024 
1025 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1026 static struct attribute *pcm_dev_attrs[] = {
1027 	&dev_attr_pcm_class.attr,
1028 	NULL
1029 };
1030 
1031 static struct attribute_group pcm_dev_attr_group = {
1032 	.attrs	= pcm_dev_attrs,
1033 };
1034 
1035 static const struct attribute_group *pcm_dev_attr_groups[] = {
1036 	&pcm_dev_attr_group,
1037 	NULL
1038 };
1039 
1040 static int snd_pcm_dev_register(struct snd_device *device)
1041 {
1042 	int cidx, err;
1043 	struct snd_pcm_substream *substream;
1044 	struct snd_pcm_notify *notify;
1045 	char str[16];
1046 	struct snd_pcm *pcm;
1047 	struct device *dev;
1048 
1049 	if (snd_BUG_ON(!device || !device->device_data))
1050 		return -ENXIO;
1051 	pcm = device->device_data;
1052 	mutex_lock(&register_mutex);
1053 	err = snd_pcm_add(pcm);
1054 	if (err) {
1055 		mutex_unlock(&register_mutex);
1056 		return err;
1057 	}
1058 	for (cidx = 0; cidx < 2; cidx++) {
1059 		int devtype = -1;
1060 		if (pcm->streams[cidx].substream == NULL || pcm->internal)
1061 			continue;
1062 		switch (cidx) {
1063 		case SNDRV_PCM_STREAM_PLAYBACK:
1064 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1065 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1066 			break;
1067 		case SNDRV_PCM_STREAM_CAPTURE:
1068 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1069 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1070 			break;
1071 		}
1072 		/* device pointer to use, pcm->dev takes precedence if
1073 		 * it is assigned, otherwise fall back to card's device
1074 		 * if possible */
1075 		dev = pcm->dev;
1076 		if (!dev)
1077 			dev = snd_card_get_device_link(pcm->card);
1078 		/* register pcm */
1079 		err = snd_register_device_for_dev(devtype, pcm->card,
1080 						  pcm->device,
1081 						  &snd_pcm_f_ops[cidx],
1082 						  pcm, str, dev);
1083 		if (err < 0) {
1084 			list_del(&pcm->list);
1085 			mutex_unlock(&register_mutex);
1086 			return err;
1087 		}
1088 
1089 		dev = snd_get_device(devtype, pcm->card, pcm->device);
1090 		if (dev) {
1091 			err = sysfs_create_groups(&dev->kobj,
1092 						  pcm_dev_attr_groups);
1093 			if (err < 0)
1094 				dev_warn(dev,
1095 					 "pcm %d:%d: cannot create sysfs groups\n",
1096 					 pcm->card->number, pcm->device);
1097 			put_device(dev);
1098 		}
1099 
1100 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1101 			snd_pcm_timer_init(substream);
1102 	}
1103 
1104 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1105 		notify->n_register(pcm);
1106 
1107 	mutex_unlock(&register_mutex);
1108 	return 0;
1109 }
1110 
1111 static int snd_pcm_dev_disconnect(struct snd_device *device)
1112 {
1113 	struct snd_pcm *pcm = device->device_data;
1114 	struct snd_pcm_notify *notify;
1115 	struct snd_pcm_substream *substream;
1116 	int cidx, devtype;
1117 
1118 	mutex_lock(&register_mutex);
1119 	if (list_empty(&pcm->list))
1120 		goto unlock;
1121 
1122 	mutex_lock(&pcm->open_mutex);
1123 	wake_up(&pcm->open_wait);
1124 	list_del_init(&pcm->list);
1125 	for (cidx = 0; cidx < 2; cidx++)
1126 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1127 			snd_pcm_stream_lock_irq(substream);
1128 			if (substream->runtime) {
1129 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1130 				wake_up(&substream->runtime->sleep);
1131 				wake_up(&substream->runtime->tsleep);
1132 			}
1133 			snd_pcm_stream_unlock_irq(substream);
1134 		}
1135 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1136 		notify->n_disconnect(pcm);
1137 	}
1138 	for (cidx = 0; cidx < 2; cidx++) {
1139 		devtype = -1;
1140 		switch (cidx) {
1141 		case SNDRV_PCM_STREAM_PLAYBACK:
1142 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1143 			break;
1144 		case SNDRV_PCM_STREAM_CAPTURE:
1145 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1146 			break;
1147 		}
1148 		snd_unregister_device(devtype, pcm->card, pcm->device);
1149 		if (pcm->streams[cidx].chmap_kctl) {
1150 			snd_ctl_remove(pcm->card, pcm->streams[cidx].chmap_kctl);
1151 			pcm->streams[cidx].chmap_kctl = NULL;
1152 		}
1153 	}
1154 	mutex_unlock(&pcm->open_mutex);
1155  unlock:
1156 	mutex_unlock(&register_mutex);
1157 	return 0;
1158 }
1159 
1160 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1161 {
1162 	struct snd_pcm *pcm;
1163 
1164 	if (snd_BUG_ON(!notify ||
1165 		       !notify->n_register ||
1166 		       !notify->n_unregister ||
1167 		       !notify->n_disconnect))
1168 		return -EINVAL;
1169 	mutex_lock(&register_mutex);
1170 	if (nfree) {
1171 		list_del(&notify->list);
1172 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1173 			notify->n_unregister(pcm);
1174 	} else {
1175 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1176 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1177 			notify->n_register(pcm);
1178 	}
1179 	mutex_unlock(&register_mutex);
1180 	return 0;
1181 }
1182 
1183 EXPORT_SYMBOL(snd_pcm_notify);
1184 
1185 #ifdef CONFIG_PROC_FS
1186 /*
1187  *  Info interface
1188  */
1189 
1190 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1191 			      struct snd_info_buffer *buffer)
1192 {
1193 	struct snd_pcm *pcm;
1194 
1195 	mutex_lock(&register_mutex);
1196 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1197 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1198 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1199 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1200 			snd_iprintf(buffer, " : playback %i",
1201 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1202 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1203 			snd_iprintf(buffer, " : capture %i",
1204 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1205 		snd_iprintf(buffer, "\n");
1206 	}
1207 	mutex_unlock(&register_mutex);
1208 }
1209 
1210 static struct snd_info_entry *snd_pcm_proc_entry;
1211 
1212 static void snd_pcm_proc_init(void)
1213 {
1214 	struct snd_info_entry *entry;
1215 
1216 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1217 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1218 		if (snd_info_register(entry) < 0) {
1219 			snd_info_free_entry(entry);
1220 			entry = NULL;
1221 		}
1222 	}
1223 	snd_pcm_proc_entry = entry;
1224 }
1225 
1226 static void snd_pcm_proc_done(void)
1227 {
1228 	snd_info_free_entry(snd_pcm_proc_entry);
1229 }
1230 
1231 #else /* !CONFIG_PROC_FS */
1232 #define snd_pcm_proc_init()
1233 #define snd_pcm_proc_done()
1234 #endif /* CONFIG_PROC_FS */
1235 
1236 
1237 /*
1238  *  ENTRY functions
1239  */
1240 
1241 static int __init alsa_pcm_init(void)
1242 {
1243 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1244 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1245 	snd_pcm_proc_init();
1246 	return 0;
1247 }
1248 
1249 static void __exit alsa_pcm_exit(void)
1250 {
1251 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1252 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1253 	snd_pcm_proc_done();
1254 }
1255 
1256 module_init(alsa_pcm_init)
1257 module_exit(alsa_pcm_exit)
1258