xref: /linux/sound/core/pcm.c (revision 40de53fd002c6ba087a623722915e8006ed68a02)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Digital Audio (PCM) abstract layer
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <linux/init.h>
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/time.h>
11 #include <linux/mutex.h>
12 #include <linux/device.h>
13 #include <linux/nospec.h>
14 #include <sound/core.h>
15 #include <sound/minors.h>
16 #include <sound/pcm.h>
17 #include <sound/timer.h>
18 #include <sound/control.h>
19 #include <sound/info.h>
20 
21 #include "pcm_local.h"
22 
23 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
24 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
25 MODULE_LICENSE("GPL");
26 
27 static LIST_HEAD(snd_pcm_devices);
28 static DEFINE_MUTEX(register_mutex);
29 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
30 static LIST_HEAD(snd_pcm_notify_list);
31 #endif
32 
33 static int snd_pcm_free(struct snd_pcm *pcm);
34 static int snd_pcm_dev_free(struct snd_device *device);
35 static int snd_pcm_dev_register(struct snd_device *device);
36 static int snd_pcm_dev_disconnect(struct snd_device *device);
37 
38 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
39 {
40 	struct snd_pcm *pcm;
41 
42 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
43 		if (pcm->card == card && pcm->device == device)
44 			return pcm;
45 	}
46 	return NULL;
47 }
48 
49 static int snd_pcm_next(struct snd_card *card, int device)
50 {
51 	struct snd_pcm *pcm;
52 
53 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
54 		if (pcm->card == card && pcm->device > device)
55 			return pcm->device;
56 		else if (pcm->card->number > card->number)
57 			return -1;
58 	}
59 	return -1;
60 }
61 
62 static int snd_pcm_add(struct snd_pcm *newpcm)
63 {
64 	struct snd_pcm *pcm;
65 
66 	if (newpcm->internal)
67 		return 0;
68 
69 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
70 		if (pcm->card == newpcm->card && pcm->device == newpcm->device)
71 			return -EBUSY;
72 		if (pcm->card->number > newpcm->card->number ||
73 				(pcm->card == newpcm->card &&
74 				pcm->device > newpcm->device)) {
75 			list_add(&newpcm->list, pcm->list.prev);
76 			return 0;
77 		}
78 	}
79 	list_add_tail(&newpcm->list, &snd_pcm_devices);
80 	return 0;
81 }
82 
83 static int snd_pcm_control_ioctl(struct snd_card *card,
84 				 struct snd_ctl_file *control,
85 				 unsigned int cmd, unsigned long arg)
86 {
87 	switch (cmd) {
88 	case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
89 		{
90 			int device;
91 
92 			if (get_user(device, (int __user *)arg))
93 				return -EFAULT;
94 			mutex_lock(&register_mutex);
95 			device = snd_pcm_next(card, device);
96 			mutex_unlock(&register_mutex);
97 			if (put_user(device, (int __user *)arg))
98 				return -EFAULT;
99 			return 0;
100 		}
101 	case SNDRV_CTL_IOCTL_PCM_INFO:
102 		{
103 			struct snd_pcm_info __user *info;
104 			unsigned int device, subdevice;
105 			int stream;
106 			struct snd_pcm *pcm;
107 			struct snd_pcm_str *pstr;
108 			struct snd_pcm_substream *substream;
109 			int err;
110 
111 			info = (struct snd_pcm_info __user *)arg;
112 			if (get_user(device, &info->device))
113 				return -EFAULT;
114 			if (get_user(stream, &info->stream))
115 				return -EFAULT;
116 			if (stream < 0 || stream > 1)
117 				return -EINVAL;
118 			stream = array_index_nospec(stream, 2);
119 			if (get_user(subdevice, &info->subdevice))
120 				return -EFAULT;
121 			mutex_lock(&register_mutex);
122 			pcm = snd_pcm_get(card, device);
123 			if (pcm == NULL) {
124 				err = -ENXIO;
125 				goto _error;
126 			}
127 			pstr = &pcm->streams[stream];
128 			if (pstr->substream_count == 0) {
129 				err = -ENOENT;
130 				goto _error;
131 			}
132 			if (subdevice >= pstr->substream_count) {
133 				err = -ENXIO;
134 				goto _error;
135 			}
136 			for (substream = pstr->substream; substream;
137 			     substream = substream->next)
138 				if (substream->number == (int)subdevice)
139 					break;
140 			if (substream == NULL) {
141 				err = -ENXIO;
142 				goto _error;
143 			}
144 			mutex_lock(&pcm->open_mutex);
145 			err = snd_pcm_info_user(substream, info);
146 			mutex_unlock(&pcm->open_mutex);
147 		_error:
148 			mutex_unlock(&register_mutex);
149 			return err;
150 		}
151 	case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
152 		{
153 			int val;
154 
155 			if (get_user(val, (int __user *)arg))
156 				return -EFAULT;
157 			control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
158 			return 0;
159 		}
160 	}
161 	return -ENOIOCTLCMD;
162 }
163 
164 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
165 
166 static const char * const snd_pcm_format_names[] = {
167 	FORMAT(S8),
168 	FORMAT(U8),
169 	FORMAT(S16_LE),
170 	FORMAT(S16_BE),
171 	FORMAT(U16_LE),
172 	FORMAT(U16_BE),
173 	FORMAT(S24_LE),
174 	FORMAT(S24_BE),
175 	FORMAT(U24_LE),
176 	FORMAT(U24_BE),
177 	FORMAT(S32_LE),
178 	FORMAT(S32_BE),
179 	FORMAT(U32_LE),
180 	FORMAT(U32_BE),
181 	FORMAT(FLOAT_LE),
182 	FORMAT(FLOAT_BE),
183 	FORMAT(FLOAT64_LE),
184 	FORMAT(FLOAT64_BE),
185 	FORMAT(IEC958_SUBFRAME_LE),
186 	FORMAT(IEC958_SUBFRAME_BE),
187 	FORMAT(MU_LAW),
188 	FORMAT(A_LAW),
189 	FORMAT(IMA_ADPCM),
190 	FORMAT(MPEG),
191 	FORMAT(GSM),
192 	FORMAT(SPECIAL),
193 	FORMAT(S24_3LE),
194 	FORMAT(S24_3BE),
195 	FORMAT(U24_3LE),
196 	FORMAT(U24_3BE),
197 	FORMAT(S20_3LE),
198 	FORMAT(S20_3BE),
199 	FORMAT(U20_3LE),
200 	FORMAT(U20_3BE),
201 	FORMAT(S18_3LE),
202 	FORMAT(S18_3BE),
203 	FORMAT(U18_3LE),
204 	FORMAT(U18_3BE),
205 	FORMAT(G723_24),
206 	FORMAT(G723_24_1B),
207 	FORMAT(G723_40),
208 	FORMAT(G723_40_1B),
209 	FORMAT(DSD_U8),
210 	FORMAT(DSD_U16_LE),
211 	FORMAT(DSD_U32_LE),
212 	FORMAT(DSD_U16_BE),
213 	FORMAT(DSD_U32_BE),
214 	FORMAT(S20_LE),
215 	FORMAT(S20_BE),
216 	FORMAT(U20_LE),
217 	FORMAT(U20_BE),
218 };
219 
220 /**
221  * snd_pcm_format_name - Return a name string for the given PCM format
222  * @format: PCM format
223  *
224  * Return: the format name string
225  */
226 const char *snd_pcm_format_name(snd_pcm_format_t format)
227 {
228 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
229 		return "Unknown";
230 	return snd_pcm_format_names[(__force unsigned int)format];
231 }
232 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
233 
234 #ifdef CONFIG_SND_VERBOSE_PROCFS
235 
236 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
237 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
238 #define READY(v) [SNDRV_PCM_READY_##v] = #v
239 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
240 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
241 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
242 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
243 #define START(v) [SNDRV_PCM_START_##v] = #v
244 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
245 
246 static const char * const snd_pcm_stream_names[] = {
247 	STREAM(PLAYBACK),
248 	STREAM(CAPTURE),
249 };
250 
251 static const char * const snd_pcm_state_names[] = {
252 	STATE(OPEN),
253 	STATE(SETUP),
254 	STATE(PREPARED),
255 	STATE(RUNNING),
256 	STATE(XRUN),
257 	STATE(DRAINING),
258 	STATE(PAUSED),
259 	STATE(SUSPENDED),
260 	STATE(DISCONNECTED),
261 };
262 
263 static const char * const snd_pcm_access_names[] = {
264 	ACCESS(MMAP_INTERLEAVED),
265 	ACCESS(MMAP_NONINTERLEAVED),
266 	ACCESS(MMAP_COMPLEX),
267 	ACCESS(RW_INTERLEAVED),
268 	ACCESS(RW_NONINTERLEAVED),
269 };
270 
271 static const char * const snd_pcm_subformat_names[] = {
272 	SUBFORMAT(STD),
273 	SUBFORMAT(MSBITS_MAX),
274 	SUBFORMAT(MSBITS_20),
275 	SUBFORMAT(MSBITS_24),
276 };
277 
278 static const char * const snd_pcm_tstamp_mode_names[] = {
279 	TSTAMP(NONE),
280 	TSTAMP(ENABLE),
281 };
282 
283 static const char *snd_pcm_stream_name(int stream)
284 {
285 	return snd_pcm_stream_names[stream];
286 }
287 
288 static const char *snd_pcm_access_name(snd_pcm_access_t access)
289 {
290 	return snd_pcm_access_names[(__force int)access];
291 }
292 
293 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
294 {
295 	return snd_pcm_subformat_names[(__force int)subformat];
296 }
297 
298 static const char *snd_pcm_tstamp_mode_name(int mode)
299 {
300 	return snd_pcm_tstamp_mode_names[mode];
301 }
302 
303 static const char *snd_pcm_state_name(snd_pcm_state_t state)
304 {
305 	return snd_pcm_state_names[(__force int)state];
306 }
307 
308 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
309 #include <linux/soundcard.h>
310 
311 static const char *snd_pcm_oss_format_name(int format)
312 {
313 	switch (format) {
314 	case AFMT_MU_LAW:
315 		return "MU_LAW";
316 	case AFMT_A_LAW:
317 		return "A_LAW";
318 	case AFMT_IMA_ADPCM:
319 		return "IMA_ADPCM";
320 	case AFMT_U8:
321 		return "U8";
322 	case AFMT_S16_LE:
323 		return "S16_LE";
324 	case AFMT_S16_BE:
325 		return "S16_BE";
326 	case AFMT_S8:
327 		return "S8";
328 	case AFMT_U16_LE:
329 		return "U16_LE";
330 	case AFMT_U16_BE:
331 		return "U16_BE";
332 	case AFMT_MPEG:
333 		return "MPEG";
334 	default:
335 		return "unknown";
336 	}
337 }
338 #endif
339 
340 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
341 				   struct snd_info_buffer *buffer)
342 {
343 	struct snd_pcm_info *info;
344 	int err;
345 
346 	if (! substream)
347 		return;
348 
349 	info = kmalloc(sizeof(*info), GFP_KERNEL);
350 	if (!info)
351 		return;
352 
353 	err = snd_pcm_info(substream, info);
354 	if (err < 0) {
355 		snd_iprintf(buffer, "error %d\n", err);
356 		kfree(info);
357 		return;
358 	}
359 	snd_iprintf(buffer, "card: %d\n", info->card);
360 	snd_iprintf(buffer, "device: %d\n", info->device);
361 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
362 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
363 	snd_iprintf(buffer, "id: %s\n", info->id);
364 	snd_iprintf(buffer, "name: %s\n", info->name);
365 	snd_iprintf(buffer, "subname: %s\n", info->subname);
366 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
367 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
368 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
369 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
370 	kfree(info);
371 }
372 
373 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
374 					  struct snd_info_buffer *buffer)
375 {
376 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
377 			       buffer);
378 }
379 
380 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
381 					     struct snd_info_buffer *buffer)
382 {
383 	snd_pcm_proc_info_read(entry->private_data, buffer);
384 }
385 
386 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
387 						  struct snd_info_buffer *buffer)
388 {
389 	struct snd_pcm_substream *substream = entry->private_data;
390 	struct snd_pcm_runtime *runtime;
391 
392 	mutex_lock(&substream->pcm->open_mutex);
393 	runtime = substream->runtime;
394 	if (!runtime) {
395 		snd_iprintf(buffer, "closed\n");
396 		goto unlock;
397 	}
398 	if (runtime->state == SNDRV_PCM_STATE_OPEN) {
399 		snd_iprintf(buffer, "no setup\n");
400 		goto unlock;
401 	}
402 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
403 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
404 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
405 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
406 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
407 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
408 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
409 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
410 	if (substream->oss.oss) {
411 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
412 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
413 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
414 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
415 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
416 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
417 	}
418 #endif
419  unlock:
420 	mutex_unlock(&substream->pcm->open_mutex);
421 }
422 
423 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
424 						  struct snd_info_buffer *buffer)
425 {
426 	struct snd_pcm_substream *substream = entry->private_data;
427 	struct snd_pcm_runtime *runtime;
428 
429 	mutex_lock(&substream->pcm->open_mutex);
430 	runtime = substream->runtime;
431 	if (!runtime) {
432 		snd_iprintf(buffer, "closed\n");
433 		goto unlock;
434 	}
435 	if (runtime->state == SNDRV_PCM_STATE_OPEN) {
436 		snd_iprintf(buffer, "no setup\n");
437 		goto unlock;
438 	}
439 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
440 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
441 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
442 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
443 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
444 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
445 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
446 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
447  unlock:
448 	mutex_unlock(&substream->pcm->open_mutex);
449 }
450 
451 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
452 					       struct snd_info_buffer *buffer)
453 {
454 	struct snd_pcm_substream *substream = entry->private_data;
455 	struct snd_pcm_runtime *runtime;
456 	struct snd_pcm_status64 status;
457 	int err;
458 
459 	mutex_lock(&substream->pcm->open_mutex);
460 	runtime = substream->runtime;
461 	if (!runtime) {
462 		snd_iprintf(buffer, "closed\n");
463 		goto unlock;
464 	}
465 	memset(&status, 0, sizeof(status));
466 	err = snd_pcm_status64(substream, &status);
467 	if (err < 0) {
468 		snd_iprintf(buffer, "error %d\n", err);
469 		goto unlock;
470 	}
471 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
472 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
473 	snd_iprintf(buffer, "trigger_time: %lld.%09lld\n",
474 		status.trigger_tstamp_sec, status.trigger_tstamp_nsec);
475 	snd_iprintf(buffer, "tstamp      : %lld.%09lld\n",
476 		status.tstamp_sec, status.tstamp_nsec);
477 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
478 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
479 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
480 	snd_iprintf(buffer, "-----\n");
481 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
482 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
483  unlock:
484 	mutex_unlock(&substream->pcm->open_mutex);
485 }
486 
487 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
488 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
489 					 struct snd_info_buffer *buffer)
490 {
491 	struct snd_pcm_substream *substream = entry->private_data;
492 
493 	snd_pcm_stop_xrun(substream);
494 }
495 
496 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
497 				    struct snd_info_buffer *buffer)
498 {
499 	struct snd_pcm_str *pstr = entry->private_data;
500 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
501 }
502 
503 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
504 				     struct snd_info_buffer *buffer)
505 {
506 	struct snd_pcm_str *pstr = entry->private_data;
507 	char line[64];
508 	if (!snd_info_get_line(buffer, line, sizeof(line)))
509 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
510 }
511 #endif
512 
513 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
514 {
515 	struct snd_pcm *pcm = pstr->pcm;
516 	struct snd_info_entry *entry;
517 	char name[16];
518 
519 	sprintf(name, "pcm%i%c", pcm->device,
520 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
521 	entry = snd_info_create_card_entry(pcm->card, name,
522 					   pcm->card->proc_root);
523 	if (!entry)
524 		return -ENOMEM;
525 	entry->mode = S_IFDIR | 0555;
526 	pstr->proc_root = entry;
527 	entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
528 	if (entry)
529 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
530 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
531 	entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
532 					   pstr->proc_root);
533 	if (entry) {
534 		snd_info_set_text_ops(entry, pstr, snd_pcm_xrun_debug_read);
535 		entry->c.text.write = snd_pcm_xrun_debug_write;
536 		entry->mode |= 0200;
537 	}
538 #endif
539 	return 0;
540 }
541 
542 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
543 {
544 	snd_info_free_entry(pstr->proc_root);
545 	pstr->proc_root = NULL;
546 	return 0;
547 }
548 
549 static struct snd_info_entry *
550 create_substream_info_entry(struct snd_pcm_substream *substream,
551 			    const char *name,
552 			    void (*read)(struct snd_info_entry *,
553 					 struct snd_info_buffer *))
554 {
555 	struct snd_info_entry *entry;
556 
557 	entry = snd_info_create_card_entry(substream->pcm->card, name,
558 					   substream->proc_root);
559 	if (entry)
560 		snd_info_set_text_ops(entry, substream, read);
561 	return entry;
562 }
563 
564 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
565 {
566 	struct snd_info_entry *entry;
567 	struct snd_card *card;
568 	char name[16];
569 
570 	card = substream->pcm->card;
571 
572 	sprintf(name, "sub%i", substream->number);
573 	entry = snd_info_create_card_entry(card, name,
574 					   substream->pstr->proc_root);
575 	if (!entry)
576 		return -ENOMEM;
577 	entry->mode = S_IFDIR | 0555;
578 	substream->proc_root = entry;
579 
580 	create_substream_info_entry(substream, "info",
581 				    snd_pcm_substream_proc_info_read);
582 	create_substream_info_entry(substream, "hw_params",
583 				    snd_pcm_substream_proc_hw_params_read);
584 	create_substream_info_entry(substream, "sw_params",
585 				    snd_pcm_substream_proc_sw_params_read);
586 	create_substream_info_entry(substream, "status",
587 				    snd_pcm_substream_proc_status_read);
588 
589 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
590 	entry = create_substream_info_entry(substream, "xrun_injection", NULL);
591 	if (entry) {
592 		entry->c.text.write = snd_pcm_xrun_injection_write;
593 		entry->mode = S_IFREG | 0200;
594 	}
595 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
596 
597 	return 0;
598 }
599 
600 #else /* !CONFIG_SND_VERBOSE_PROCFS */
601 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
602 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
603 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
604 #endif /* CONFIG_SND_VERBOSE_PROCFS */
605 
606 static const struct attribute_group *pcm_dev_attr_groups[];
607 
608 /*
609  * PM callbacks: we need to deal only with suspend here, as the resume is
610  * triggered either from user-space or the driver's resume callback
611  */
612 #ifdef CONFIG_PM_SLEEP
613 static int do_pcm_suspend(struct device *dev)
614 {
615 	struct snd_pcm_str *pstr = dev_get_drvdata(dev);
616 
617 	if (!pstr->pcm->no_device_suspend)
618 		snd_pcm_suspend_all(pstr->pcm);
619 	return 0;
620 }
621 #endif
622 
623 static const struct dev_pm_ops pcm_dev_pm_ops = {
624 	SET_SYSTEM_SLEEP_PM_OPS(do_pcm_suspend, NULL)
625 };
626 
627 /* device type for PCM -- basically only for passing PM callbacks */
628 static const struct device_type pcm_dev_type = {
629 	.name = "pcm",
630 	.pm = &pcm_dev_pm_ops,
631 };
632 
633 /**
634  * snd_pcm_new_stream - create a new PCM stream
635  * @pcm: the pcm instance
636  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
637  * @substream_count: the number of substreams
638  *
639  * Creates a new stream for the pcm.
640  * The corresponding stream on the pcm must have been empty before
641  * calling this, i.e. zero must be given to the argument of
642  * snd_pcm_new().
643  *
644  * Return: Zero if successful, or a negative error code on failure.
645  */
646 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
647 {
648 	int idx, err;
649 	struct snd_pcm_str *pstr = &pcm->streams[stream];
650 	struct snd_pcm_substream *substream, *prev;
651 
652 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
653 	mutex_init(&pstr->oss.setup_mutex);
654 #endif
655 	pstr->stream = stream;
656 	pstr->pcm = pcm;
657 	pstr->substream_count = substream_count;
658 	if (!substream_count)
659 		return 0;
660 
661 	err = snd_device_alloc(&pstr->dev, pcm->card);
662 	if (err < 0)
663 		return err;
664 	dev_set_name(pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
665 		     stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
666 	pstr->dev->groups = pcm_dev_attr_groups;
667 	pstr->dev->type = &pcm_dev_type;
668 	dev_set_drvdata(pstr->dev, pstr);
669 
670 	if (!pcm->internal) {
671 		err = snd_pcm_stream_proc_init(pstr);
672 		if (err < 0) {
673 			pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
674 			return err;
675 		}
676 	}
677 	prev = NULL;
678 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
679 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
680 		if (!substream)
681 			return -ENOMEM;
682 		substream->pcm = pcm;
683 		substream->pstr = pstr;
684 		substream->number = idx;
685 		substream->stream = stream;
686 		sprintf(substream->name, "subdevice #%i", idx);
687 		substream->buffer_bytes_max = UINT_MAX;
688 		if (prev == NULL)
689 			pstr->substream = substream;
690 		else
691 			prev->next = substream;
692 
693 		if (!pcm->internal) {
694 			err = snd_pcm_substream_proc_init(substream);
695 			if (err < 0) {
696 				pcm_err(pcm,
697 					"Error in snd_pcm_stream_proc_init\n");
698 				if (prev == NULL)
699 					pstr->substream = NULL;
700 				else
701 					prev->next = NULL;
702 				kfree(substream);
703 				return err;
704 			}
705 		}
706 		substream->group = &substream->self_group;
707 		snd_pcm_group_init(&substream->self_group);
708 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
709 		atomic_set(&substream->mmap_count, 0);
710 		prev = substream;
711 	}
712 	return 0;
713 }
714 EXPORT_SYMBOL(snd_pcm_new_stream);
715 
716 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
717 		int playback_count, int capture_count, bool internal,
718 		struct snd_pcm **rpcm)
719 {
720 	struct snd_pcm *pcm;
721 	int err;
722 	static const struct snd_device_ops ops = {
723 		.dev_free = snd_pcm_dev_free,
724 		.dev_register =	snd_pcm_dev_register,
725 		.dev_disconnect = snd_pcm_dev_disconnect,
726 	};
727 	static const struct snd_device_ops internal_ops = {
728 		.dev_free = snd_pcm_dev_free,
729 	};
730 
731 	if (snd_BUG_ON(!card))
732 		return -ENXIO;
733 	if (rpcm)
734 		*rpcm = NULL;
735 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
736 	if (!pcm)
737 		return -ENOMEM;
738 	pcm->card = card;
739 	pcm->device = device;
740 	pcm->internal = internal;
741 	mutex_init(&pcm->open_mutex);
742 	init_waitqueue_head(&pcm->open_wait);
743 	INIT_LIST_HEAD(&pcm->list);
744 	if (id)
745 		strscpy(pcm->id, id, sizeof(pcm->id));
746 
747 	err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
748 				 playback_count);
749 	if (err < 0)
750 		goto free_pcm;
751 
752 	err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
753 	if (err < 0)
754 		goto free_pcm;
755 
756 	err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
757 			     internal ? &internal_ops : &ops);
758 	if (err < 0)
759 		goto free_pcm;
760 
761 	if (rpcm)
762 		*rpcm = pcm;
763 	return 0;
764 
765 free_pcm:
766 	snd_pcm_free(pcm);
767 	return err;
768 }
769 
770 /**
771  * snd_pcm_new - create a new PCM instance
772  * @card: the card instance
773  * @id: the id string
774  * @device: the device index (zero based)
775  * @playback_count: the number of substreams for playback
776  * @capture_count: the number of substreams for capture
777  * @rpcm: the pointer to store the new pcm instance
778  *
779  * Creates a new PCM instance.
780  *
781  * The pcm operators have to be set afterwards to the new instance
782  * via snd_pcm_set_ops().
783  *
784  * Return: Zero if successful, or a negative error code on failure.
785  */
786 int snd_pcm_new(struct snd_card *card, const char *id, int device,
787 		int playback_count, int capture_count, struct snd_pcm **rpcm)
788 {
789 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
790 			false, rpcm);
791 }
792 EXPORT_SYMBOL(snd_pcm_new);
793 
794 /**
795  * snd_pcm_new_internal - create a new internal PCM instance
796  * @card: the card instance
797  * @id: the id string
798  * @device: the device index (zero based - shared with normal PCMs)
799  * @playback_count: the number of substreams for playback
800  * @capture_count: the number of substreams for capture
801  * @rpcm: the pointer to store the new pcm instance
802  *
803  * Creates a new internal PCM instance with no userspace device or procfs
804  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
805  * will only be used internally by kernel drivers. i.e. it cannot be opened
806  * by userspace. It provides existing ASoC components drivers with a substream
807  * and access to any private data.
808  *
809  * The pcm operators have to be set afterwards to the new instance
810  * via snd_pcm_set_ops().
811  *
812  * Return: Zero if successful, or a negative error code on failure.
813  */
814 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
815 	int playback_count, int capture_count,
816 	struct snd_pcm **rpcm)
817 {
818 	return _snd_pcm_new(card, id, device, playback_count, capture_count,
819 			true, rpcm);
820 }
821 EXPORT_SYMBOL(snd_pcm_new_internal);
822 
823 static void free_chmap(struct snd_pcm_str *pstr)
824 {
825 	if (pstr->chmap_kctl) {
826 		struct snd_card *card = pstr->pcm->card;
827 
828 		snd_ctl_remove(card, pstr->chmap_kctl);
829 		pstr->chmap_kctl = NULL;
830 	}
831 }
832 
833 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
834 {
835 	struct snd_pcm_substream *substream, *substream_next;
836 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
837 	struct snd_pcm_oss_setup *setup, *setupn;
838 #endif
839 
840 	/* free all proc files under the stream */
841 	snd_pcm_stream_proc_done(pstr);
842 
843 	substream = pstr->substream;
844 	while (substream) {
845 		substream_next = substream->next;
846 		snd_pcm_timer_done(substream);
847 		kfree(substream);
848 		substream = substream_next;
849 	}
850 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
851 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
852 		setupn = setup->next;
853 		kfree(setup->task_name);
854 		kfree(setup);
855 	}
856 #endif
857 	free_chmap(pstr);
858 	if (pstr->substream_count)
859 		put_device(pstr->dev);
860 }
861 
862 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
863 #define pcm_call_notify(pcm, call)					\
864 	do {								\
865 		struct snd_pcm_notify *_notify;				\
866 		list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
867 			_notify->call(pcm);				\
868 	} while (0)
869 #else
870 #define pcm_call_notify(pcm, call) do {} while (0)
871 #endif
872 
873 static int snd_pcm_free(struct snd_pcm *pcm)
874 {
875 	if (!pcm)
876 		return 0;
877 	if (!pcm->internal)
878 		pcm_call_notify(pcm, n_unregister);
879 	if (pcm->private_free)
880 		pcm->private_free(pcm);
881 	snd_pcm_lib_preallocate_free_for_all(pcm);
882 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
883 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
884 	kfree(pcm);
885 	return 0;
886 }
887 
888 static int snd_pcm_dev_free(struct snd_device *device)
889 {
890 	struct snd_pcm *pcm = device->device_data;
891 	return snd_pcm_free(pcm);
892 }
893 
894 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
895 			     struct file *file,
896 			     struct snd_pcm_substream **rsubstream)
897 {
898 	struct snd_pcm_str * pstr;
899 	struct snd_pcm_substream *substream;
900 	struct snd_pcm_runtime *runtime;
901 	struct snd_card *card;
902 	int prefer_subdevice;
903 	size_t size;
904 
905 	if (snd_BUG_ON(!pcm || !rsubstream))
906 		return -ENXIO;
907 	if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
908 		       stream != SNDRV_PCM_STREAM_CAPTURE))
909 		return -EINVAL;
910 	*rsubstream = NULL;
911 	pstr = &pcm->streams[stream];
912 	if (pstr->substream == NULL || pstr->substream_count == 0)
913 		return -ENODEV;
914 
915 	card = pcm->card;
916 	prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
917 
918 	if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
919 		int opposite = !stream;
920 
921 		for (substream = pcm->streams[opposite].substream; substream;
922 		     substream = substream->next) {
923 			if (SUBSTREAM_BUSY(substream))
924 				return -EAGAIN;
925 		}
926 	}
927 
928 	if (file->f_flags & O_APPEND) {
929 		if (prefer_subdevice < 0) {
930 			if (pstr->substream_count > 1)
931 				return -EINVAL; /* must be unique */
932 			substream = pstr->substream;
933 		} else {
934 			for (substream = pstr->substream; substream;
935 			     substream = substream->next)
936 				if (substream->number == prefer_subdevice)
937 					break;
938 		}
939 		if (! substream)
940 			return -ENODEV;
941 		if (! SUBSTREAM_BUSY(substream))
942 			return -EBADFD;
943 		substream->ref_count++;
944 		*rsubstream = substream;
945 		return 0;
946 	}
947 
948 	for (substream = pstr->substream; substream; substream = substream->next) {
949 		if (!SUBSTREAM_BUSY(substream) &&
950 		    (prefer_subdevice == -1 ||
951 		     substream->number == prefer_subdevice))
952 			break;
953 	}
954 	if (substream == NULL)
955 		return -EAGAIN;
956 
957 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
958 	if (runtime == NULL)
959 		return -ENOMEM;
960 
961 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
962 	runtime->status = alloc_pages_exact(size, GFP_KERNEL);
963 	if (runtime->status == NULL) {
964 		kfree(runtime);
965 		return -ENOMEM;
966 	}
967 	memset(runtime->status, 0, size);
968 
969 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
970 	runtime->control = alloc_pages_exact(size, GFP_KERNEL);
971 	if (runtime->control == NULL) {
972 		free_pages_exact(runtime->status,
973 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
974 		kfree(runtime);
975 		return -ENOMEM;
976 	}
977 	memset(runtime->control, 0, size);
978 
979 	init_waitqueue_head(&runtime->sleep);
980 	init_waitqueue_head(&runtime->tsleep);
981 
982 	__snd_pcm_set_state(runtime, SNDRV_PCM_STATE_OPEN);
983 	mutex_init(&runtime->buffer_mutex);
984 	atomic_set(&runtime->buffer_accessing, 0);
985 
986 	substream->runtime = runtime;
987 	substream->private_data = pcm->private_data;
988 	substream->ref_count = 1;
989 	substream->f_flags = file->f_flags;
990 	substream->pid = get_pid(task_pid(current));
991 	pstr->substream_opened++;
992 	*rsubstream = substream;
993 	return 0;
994 }
995 
996 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
997 {
998 	struct snd_pcm_runtime *runtime;
999 
1000 	if (PCM_RUNTIME_CHECK(substream))
1001 		return;
1002 	runtime = substream->runtime;
1003 	if (runtime->private_free != NULL)
1004 		runtime->private_free(runtime);
1005 	free_pages_exact(runtime->status,
1006 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1007 	free_pages_exact(runtime->control,
1008 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1009 	kfree(runtime->hw_constraints.rules);
1010 	/* Avoid concurrent access to runtime via PCM timer interface */
1011 	if (substream->timer) {
1012 		spin_lock_irq(&substream->timer->lock);
1013 		substream->runtime = NULL;
1014 		spin_unlock_irq(&substream->timer->lock);
1015 	} else {
1016 		substream->runtime = NULL;
1017 	}
1018 	mutex_destroy(&runtime->buffer_mutex);
1019 	snd_fasync_free(runtime->fasync);
1020 	kfree(runtime);
1021 	put_pid(substream->pid);
1022 	substream->pid = NULL;
1023 	substream->pstr->substream_opened--;
1024 }
1025 
1026 static ssize_t pcm_class_show(struct device *dev,
1027 			      struct device_attribute *attr, char *buf)
1028 {
1029 	struct snd_pcm_str *pstr = dev_get_drvdata(dev);
1030 	struct snd_pcm *pcm = pstr->pcm;
1031 	const char *str;
1032 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1033 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
1034 		[SNDRV_PCM_CLASS_MULTI] = "multi",
1035 		[SNDRV_PCM_CLASS_MODEM] = "modem",
1036 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1037 	};
1038 
1039 	if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1040 		str = "none";
1041 	else
1042 		str = strs[pcm->dev_class];
1043 	return sysfs_emit(buf, "%s\n", str);
1044 }
1045 
1046 static DEVICE_ATTR_RO(pcm_class);
1047 static struct attribute *pcm_dev_attrs[] = {
1048 	&dev_attr_pcm_class.attr,
1049 	NULL
1050 };
1051 
1052 static const struct attribute_group pcm_dev_attr_group = {
1053 	.attrs	= pcm_dev_attrs,
1054 };
1055 
1056 static const struct attribute_group *pcm_dev_attr_groups[] = {
1057 	&pcm_dev_attr_group,
1058 	NULL
1059 };
1060 
1061 static int snd_pcm_dev_register(struct snd_device *device)
1062 {
1063 	int cidx, err;
1064 	struct snd_pcm_substream *substream;
1065 	struct snd_pcm *pcm;
1066 
1067 	if (snd_BUG_ON(!device || !device->device_data))
1068 		return -ENXIO;
1069 	pcm = device->device_data;
1070 
1071 	mutex_lock(&register_mutex);
1072 	err = snd_pcm_add(pcm);
1073 	if (err)
1074 		goto unlock;
1075 	for (cidx = 0; cidx < 2; cidx++) {
1076 		int devtype = -1;
1077 		if (pcm->streams[cidx].substream == NULL)
1078 			continue;
1079 		switch (cidx) {
1080 		case SNDRV_PCM_STREAM_PLAYBACK:
1081 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1082 			break;
1083 		case SNDRV_PCM_STREAM_CAPTURE:
1084 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1085 			break;
1086 		}
1087 		/* register pcm */
1088 		err = snd_register_device(devtype, pcm->card, pcm->device,
1089 					  &snd_pcm_f_ops[cidx], pcm,
1090 					  pcm->streams[cidx].dev);
1091 		if (err < 0) {
1092 			list_del_init(&pcm->list);
1093 			goto unlock;
1094 		}
1095 
1096 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1097 			snd_pcm_timer_init(substream);
1098 	}
1099 
1100 	pcm_call_notify(pcm, n_register);
1101 
1102  unlock:
1103 	mutex_unlock(&register_mutex);
1104 	return err;
1105 }
1106 
1107 static int snd_pcm_dev_disconnect(struct snd_device *device)
1108 {
1109 	struct snd_pcm *pcm = device->device_data;
1110 	struct snd_pcm_substream *substream;
1111 	int cidx;
1112 
1113 	mutex_lock(&register_mutex);
1114 	mutex_lock(&pcm->open_mutex);
1115 	wake_up(&pcm->open_wait);
1116 	list_del_init(&pcm->list);
1117 
1118 	for_each_pcm_substream(pcm, cidx, substream) {
1119 		snd_pcm_stream_lock_irq(substream);
1120 		if (substream->runtime) {
1121 			if (snd_pcm_running(substream))
1122 				snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
1123 			/* to be sure, set the state unconditionally */
1124 			__snd_pcm_set_state(substream->runtime,
1125 					    SNDRV_PCM_STATE_DISCONNECTED);
1126 			wake_up(&substream->runtime->sleep);
1127 			wake_up(&substream->runtime->tsleep);
1128 		}
1129 		snd_pcm_stream_unlock_irq(substream);
1130 	}
1131 
1132 	for_each_pcm_substream(pcm, cidx, substream)
1133 		snd_pcm_sync_stop(substream, false);
1134 
1135 	pcm_call_notify(pcm, n_disconnect);
1136 	for (cidx = 0; cidx < 2; cidx++) {
1137 		if (pcm->streams[cidx].dev)
1138 			snd_unregister_device(pcm->streams[cidx].dev);
1139 		free_chmap(&pcm->streams[cidx]);
1140 	}
1141 	mutex_unlock(&pcm->open_mutex);
1142 	mutex_unlock(&register_mutex);
1143 	return 0;
1144 }
1145 
1146 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1147 /**
1148  * snd_pcm_notify - Add/remove the notify list
1149  * @notify: PCM notify list
1150  * @nfree: 0 = register, 1 = unregister
1151  *
1152  * This adds the given notifier to the global list so that the callback is
1153  * called for each registered PCM devices.  This exists only for PCM OSS
1154  * emulation, so far.
1155  *
1156  * Return: zero if successful, or a negative error code
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 EXPORT_SYMBOL(snd_pcm_notify);
1181 #endif /* CONFIG_SND_PCM_OSS */
1182 
1183 #ifdef CONFIG_SND_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 	entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1215 	if (entry) {
1216 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1217 		if (snd_info_register(entry) < 0) {
1218 			snd_info_free_entry(entry);
1219 			entry = NULL;
1220 		}
1221 	}
1222 	snd_pcm_proc_entry = entry;
1223 }
1224 
1225 static void snd_pcm_proc_done(void)
1226 {
1227 	snd_info_free_entry(snd_pcm_proc_entry);
1228 }
1229 
1230 #else /* !CONFIG_SND_PROC_FS */
1231 #define snd_pcm_proc_init()
1232 #define snd_pcm_proc_done()
1233 #endif /* CONFIG_SND_PROC_FS */
1234 
1235 
1236 /*
1237  *  ENTRY functions
1238  */
1239 
1240 static int __init alsa_pcm_init(void)
1241 {
1242 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1243 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1244 	snd_pcm_proc_init();
1245 	return 0;
1246 }
1247 
1248 static void __exit alsa_pcm_exit(void)
1249 {
1250 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1251 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1252 	snd_pcm_proc_done();
1253 }
1254 
1255 module_init(alsa_pcm_init)
1256 module_exit(alsa_pcm_exit)
1257