xref: /linux/sound/core/pcm.c (revision 24942c8e5cc8696064ee207ff29d4cf21f70dafc)
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 <sound/core.h>
28 #include <sound/minors.h>
29 #include <sound/pcm.h>
30 #include <sound/control.h>
31 #include <sound/info.h>
32 
33 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
34 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
35 MODULE_LICENSE("GPL");
36 
37 static LIST_HEAD(snd_pcm_devices);
38 static LIST_HEAD(snd_pcm_notify_list);
39 static DEFINE_MUTEX(register_mutex);
40 
41 static int snd_pcm_free(struct snd_pcm *pcm);
42 static int snd_pcm_dev_free(struct snd_device *device);
43 static int snd_pcm_dev_register(struct snd_device *device);
44 static int snd_pcm_dev_disconnect(struct snd_device *device);
45 
46 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
47 {
48 	struct snd_pcm *pcm;
49 
50 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
51 		if (pcm->card == card && pcm->device == device)
52 			return pcm;
53 	}
54 	return NULL;
55 }
56 
57 static int snd_pcm_next(struct snd_card *card, int device)
58 {
59 	struct snd_pcm *pcm;
60 
61 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
62 		if (pcm->card == card && pcm->device > device)
63 			return pcm->device;
64 		else if (pcm->card->number > card->number)
65 			return -1;
66 	}
67 	return -1;
68 }
69 
70 static int snd_pcm_add(struct snd_pcm *newpcm)
71 {
72 	struct snd_pcm *pcm;
73 
74 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
75 		if (pcm->card == newpcm->card && pcm->device == newpcm->device)
76 			return -EBUSY;
77 		if (pcm->card->number > newpcm->card->number ||
78 				(pcm->card == newpcm->card &&
79 				pcm->device > newpcm->device)) {
80 			list_add(&newpcm->list, pcm->list.prev);
81 			return 0;
82 		}
83 	}
84 	list_add_tail(&newpcm->list, &snd_pcm_devices);
85 	return 0;
86 }
87 
88 static int snd_pcm_control_ioctl(struct snd_card *card,
89 				 struct snd_ctl_file *control,
90 				 unsigned int cmd, unsigned long arg)
91 {
92 	switch (cmd) {
93 	case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
94 		{
95 			int device;
96 
97 			if (get_user(device, (int __user *)arg))
98 				return -EFAULT;
99 			mutex_lock(&register_mutex);
100 			device = snd_pcm_next(card, device);
101 			mutex_unlock(&register_mutex);
102 			if (put_user(device, (int __user *)arg))
103 				return -EFAULT;
104 			return 0;
105 		}
106 	case SNDRV_CTL_IOCTL_PCM_INFO:
107 		{
108 			struct snd_pcm_info __user *info;
109 			unsigned int device, subdevice;
110 			int stream;
111 			struct snd_pcm *pcm;
112 			struct snd_pcm_str *pstr;
113 			struct snd_pcm_substream *substream;
114 			int err;
115 
116 			info = (struct snd_pcm_info __user *)arg;
117 			if (get_user(device, &info->device))
118 				return -EFAULT;
119 			if (get_user(stream, &info->stream))
120 				return -EFAULT;
121 			if (stream < 0 || stream > 1)
122 				return -EINVAL;
123 			if (get_user(subdevice, &info->subdevice))
124 				return -EFAULT;
125 			mutex_lock(&register_mutex);
126 			pcm = snd_pcm_get(card, device);
127 			if (pcm == NULL) {
128 				err = -ENXIO;
129 				goto _error;
130 			}
131 			pstr = &pcm->streams[stream];
132 			if (pstr->substream_count == 0) {
133 				err = -ENOENT;
134 				goto _error;
135 			}
136 			if (subdevice >= pstr->substream_count) {
137 				err = -ENXIO;
138 				goto _error;
139 			}
140 			for (substream = pstr->substream; substream;
141 			     substream = substream->next)
142 				if (substream->number == (int)subdevice)
143 					break;
144 			if (substream == NULL) {
145 				err = -ENXIO;
146 				goto _error;
147 			}
148 			err = snd_pcm_info_user(substream, info);
149 		_error:
150 			mutex_unlock(&register_mutex);
151 			return err;
152 		}
153 	case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
154 		{
155 			int val;
156 
157 			if (get_user(val, (int __user *)arg))
158 				return -EFAULT;
159 			control->prefer_pcm_subdevice = val;
160 			return 0;
161 		}
162 	}
163 	return -ENOIOCTLCMD;
164 }
165 
166 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
167 
168 static char *snd_pcm_format_names[] = {
169 	FORMAT(S8),
170 	FORMAT(U8),
171 	FORMAT(S16_LE),
172 	FORMAT(S16_BE),
173 	FORMAT(U16_LE),
174 	FORMAT(U16_BE),
175 	FORMAT(S24_LE),
176 	FORMAT(S24_BE),
177 	FORMAT(U24_LE),
178 	FORMAT(U24_BE),
179 	FORMAT(S32_LE),
180 	FORMAT(S32_BE),
181 	FORMAT(U32_LE),
182 	FORMAT(U32_BE),
183 	FORMAT(FLOAT_LE),
184 	FORMAT(FLOAT_BE),
185 	FORMAT(FLOAT64_LE),
186 	FORMAT(FLOAT64_BE),
187 	FORMAT(IEC958_SUBFRAME_LE),
188 	FORMAT(IEC958_SUBFRAME_BE),
189 	FORMAT(MU_LAW),
190 	FORMAT(A_LAW),
191 	FORMAT(IMA_ADPCM),
192 	FORMAT(MPEG),
193 	FORMAT(GSM),
194 	FORMAT(SPECIAL),
195 	FORMAT(S24_3LE),
196 	FORMAT(S24_3BE),
197 	FORMAT(U24_3LE),
198 	FORMAT(U24_3BE),
199 	FORMAT(S20_3LE),
200 	FORMAT(S20_3BE),
201 	FORMAT(U20_3LE),
202 	FORMAT(U20_3BE),
203 	FORMAT(S18_3LE),
204 	FORMAT(S18_3BE),
205 	FORMAT(U18_3LE),
206 	FORMAT(U18_3BE),
207 	FORMAT(G723_24),
208 	FORMAT(G723_24_1B),
209 	FORMAT(G723_40),
210 	FORMAT(G723_40_1B),
211 };
212 
213 const char *snd_pcm_format_name(snd_pcm_format_t format)
214 {
215 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
216 		return "Unknown";
217 	return snd_pcm_format_names[(__force unsigned int)format];
218 }
219 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
220 
221 #ifdef CONFIG_SND_VERBOSE_PROCFS
222 
223 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
224 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
225 #define READY(v) [SNDRV_PCM_READY_##v] = #v
226 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
227 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
228 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
229 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
230 #define START(v) [SNDRV_PCM_START_##v] = #v
231 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
232 
233 static char *snd_pcm_stream_names[] = {
234 	STREAM(PLAYBACK),
235 	STREAM(CAPTURE),
236 };
237 
238 static char *snd_pcm_state_names[] = {
239 	STATE(OPEN),
240 	STATE(SETUP),
241 	STATE(PREPARED),
242 	STATE(RUNNING),
243 	STATE(XRUN),
244 	STATE(DRAINING),
245 	STATE(PAUSED),
246 	STATE(SUSPENDED),
247 };
248 
249 static char *snd_pcm_access_names[] = {
250 	ACCESS(MMAP_INTERLEAVED),
251 	ACCESS(MMAP_NONINTERLEAVED),
252 	ACCESS(MMAP_COMPLEX),
253 	ACCESS(RW_INTERLEAVED),
254 	ACCESS(RW_NONINTERLEAVED),
255 };
256 
257 static char *snd_pcm_subformat_names[] = {
258 	SUBFORMAT(STD),
259 };
260 
261 static char *snd_pcm_tstamp_mode_names[] = {
262 	TSTAMP(NONE),
263 	TSTAMP(ENABLE),
264 };
265 
266 static const char *snd_pcm_stream_name(int stream)
267 {
268 	return snd_pcm_stream_names[stream];
269 }
270 
271 static const char *snd_pcm_access_name(snd_pcm_access_t access)
272 {
273 	return snd_pcm_access_names[(__force int)access];
274 }
275 
276 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
277 {
278 	return snd_pcm_subformat_names[(__force int)subformat];
279 }
280 
281 static const char *snd_pcm_tstamp_mode_name(int mode)
282 {
283 	return snd_pcm_tstamp_mode_names[mode];
284 }
285 
286 static const char *snd_pcm_state_name(snd_pcm_state_t state)
287 {
288 	return snd_pcm_state_names[(__force int)state];
289 }
290 
291 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
292 #include <linux/soundcard.h>
293 
294 static const char *snd_pcm_oss_format_name(int format)
295 {
296 	switch (format) {
297 	case AFMT_MU_LAW:
298 		return "MU_LAW";
299 	case AFMT_A_LAW:
300 		return "A_LAW";
301 	case AFMT_IMA_ADPCM:
302 		return "IMA_ADPCM";
303 	case AFMT_U8:
304 		return "U8";
305 	case AFMT_S16_LE:
306 		return "S16_LE";
307 	case AFMT_S16_BE:
308 		return "S16_BE";
309 	case AFMT_S8:
310 		return "S8";
311 	case AFMT_U16_LE:
312 		return "U16_LE";
313 	case AFMT_U16_BE:
314 		return "U16_BE";
315 	case AFMT_MPEG:
316 		return "MPEG";
317 	default:
318 		return "unknown";
319 	}
320 }
321 #endif
322 
323 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
324 				   struct snd_info_buffer *buffer)
325 {
326 	struct snd_pcm_info *info;
327 	int err;
328 
329 	if (! substream)
330 		return;
331 
332 	info = kmalloc(sizeof(*info), GFP_KERNEL);
333 	if (! info) {
334 		printk(KERN_DEBUG "snd_pcm_proc_info_read: cannot malloc\n");
335 		return;
336 	}
337 
338 	err = snd_pcm_info(substream, info);
339 	if (err < 0) {
340 		snd_iprintf(buffer, "error %d\n", err);
341 		kfree(info);
342 		return;
343 	}
344 	snd_iprintf(buffer, "card: %d\n", info->card);
345 	snd_iprintf(buffer, "device: %d\n", info->device);
346 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
347 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
348 	snd_iprintf(buffer, "id: %s\n", info->id);
349 	snd_iprintf(buffer, "name: %s\n", info->name);
350 	snd_iprintf(buffer, "subname: %s\n", info->subname);
351 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
352 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
353 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
354 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
355 	kfree(info);
356 }
357 
358 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
359 					  struct snd_info_buffer *buffer)
360 {
361 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
362 			       buffer);
363 }
364 
365 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
366 					     struct snd_info_buffer *buffer)
367 {
368 	snd_pcm_proc_info_read(entry->private_data, buffer);
369 }
370 
371 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
372 						  struct snd_info_buffer *buffer)
373 {
374 	struct snd_pcm_substream *substream = entry->private_data;
375 	struct snd_pcm_runtime *runtime;
376 
377 	mutex_lock(&substream->pcm->open_mutex);
378 	runtime = substream->runtime;
379 	if (!runtime) {
380 		snd_iprintf(buffer, "closed\n");
381 		goto unlock;
382 	}
383 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
384 		snd_iprintf(buffer, "no setup\n");
385 		goto unlock;
386 	}
387 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
388 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
389 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
390 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
391 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
392 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
393 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
394 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
395 	if (substream->oss.oss) {
396 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
397 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
398 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
399 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
400 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
401 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
402 	}
403 #endif
404  unlock:
405 	mutex_unlock(&substream->pcm->open_mutex);
406 }
407 
408 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
409 						  struct snd_info_buffer *buffer)
410 {
411 	struct snd_pcm_substream *substream = entry->private_data;
412 	struct snd_pcm_runtime *runtime;
413 
414 	mutex_lock(&substream->pcm->open_mutex);
415 	runtime = substream->runtime;
416 	if (!runtime) {
417 		snd_iprintf(buffer, "closed\n");
418 		goto unlock;
419 	}
420 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
421 		snd_iprintf(buffer, "no setup\n");
422 		goto unlock;
423 	}
424 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
425 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
426 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
427 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
428 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
429 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
430 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
431 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
432  unlock:
433 	mutex_unlock(&substream->pcm->open_mutex);
434 }
435 
436 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
437 					       struct snd_info_buffer *buffer)
438 {
439 	struct snd_pcm_substream *substream = entry->private_data;
440 	struct snd_pcm_runtime *runtime;
441 	struct snd_pcm_status status;
442 	int err;
443 
444 	mutex_lock(&substream->pcm->open_mutex);
445 	runtime = substream->runtime;
446 	if (!runtime) {
447 		snd_iprintf(buffer, "closed\n");
448 		goto unlock;
449 	}
450 	memset(&status, 0, sizeof(status));
451 	err = snd_pcm_status(substream, &status);
452 	if (err < 0) {
453 		snd_iprintf(buffer, "error %d\n", err);
454 		goto unlock;
455 	}
456 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
457 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
458 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
459 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
460 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
461 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
462 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
463 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
464 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
465 	snd_iprintf(buffer, "-----\n");
466 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
467 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
468  unlock:
469 	mutex_unlock(&substream->pcm->open_mutex);
470 }
471 
472 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
473 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
474 				    struct snd_info_buffer *buffer)
475 {
476 	struct snd_pcm_str *pstr = entry->private_data;
477 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
478 }
479 
480 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
481 				     struct snd_info_buffer *buffer)
482 {
483 	struct snd_pcm_str *pstr = entry->private_data;
484 	char line[64];
485 	if (!snd_info_get_line(buffer, line, sizeof(line)))
486 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
487 }
488 #endif
489 
490 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
491 {
492 	struct snd_pcm *pcm = pstr->pcm;
493 	struct snd_info_entry *entry;
494 	char name[16];
495 
496 	sprintf(name, "pcm%i%c", pcm->device,
497 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
498 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
499 		return -ENOMEM;
500 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
501 	if (snd_info_register(entry) < 0) {
502 		snd_info_free_entry(entry);
503 		return -ENOMEM;
504 	}
505 	pstr->proc_root = entry;
506 
507 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
508 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
509 		if (snd_info_register(entry) < 0) {
510 			snd_info_free_entry(entry);
511 			entry = NULL;
512 		}
513 	}
514 	pstr->proc_info_entry = entry;
515 
516 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
517 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
518 						pstr->proc_root)) != NULL) {
519 		entry->c.text.read = snd_pcm_xrun_debug_read;
520 		entry->c.text.write = snd_pcm_xrun_debug_write;
521 		entry->mode |= S_IWUSR;
522 		entry->private_data = pstr;
523 		if (snd_info_register(entry) < 0) {
524 			snd_info_free_entry(entry);
525 			entry = NULL;
526 		}
527 	}
528 	pstr->proc_xrun_debug_entry = entry;
529 #endif
530 	return 0;
531 }
532 
533 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
534 {
535 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
536 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
537 	pstr->proc_xrun_debug_entry = NULL;
538 #endif
539 	snd_info_free_entry(pstr->proc_info_entry);
540 	pstr->proc_info_entry = NULL;
541 	snd_info_free_entry(pstr->proc_root);
542 	pstr->proc_root = NULL;
543 	return 0;
544 }
545 
546 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
547 {
548 	struct snd_info_entry *entry;
549 	struct snd_card *card;
550 	char name[16];
551 
552 	card = substream->pcm->card;
553 
554 	sprintf(name, "sub%i", substream->number);
555 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
556 		return -ENOMEM;
557 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
558 	if (snd_info_register(entry) < 0) {
559 		snd_info_free_entry(entry);
560 		return -ENOMEM;
561 	}
562 	substream->proc_root = entry;
563 
564 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
565 		snd_info_set_text_ops(entry, substream,
566 				      snd_pcm_substream_proc_info_read);
567 		if (snd_info_register(entry) < 0) {
568 			snd_info_free_entry(entry);
569 			entry = NULL;
570 		}
571 	}
572 	substream->proc_info_entry = entry;
573 
574 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
575 		snd_info_set_text_ops(entry, substream,
576 				      snd_pcm_substream_proc_hw_params_read);
577 		if (snd_info_register(entry) < 0) {
578 			snd_info_free_entry(entry);
579 			entry = NULL;
580 		}
581 	}
582 	substream->proc_hw_params_entry = entry;
583 
584 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
585 		snd_info_set_text_ops(entry, substream,
586 				      snd_pcm_substream_proc_sw_params_read);
587 		if (snd_info_register(entry) < 0) {
588 			snd_info_free_entry(entry);
589 			entry = NULL;
590 		}
591 	}
592 	substream->proc_sw_params_entry = entry;
593 
594 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
595 		snd_info_set_text_ops(entry, substream,
596 				      snd_pcm_substream_proc_status_read);
597 		if (snd_info_register(entry) < 0) {
598 			snd_info_free_entry(entry);
599 			entry = NULL;
600 		}
601 	}
602 	substream->proc_status_entry = entry;
603 
604 	return 0;
605 }
606 
607 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
608 {
609 	snd_info_free_entry(substream->proc_info_entry);
610 	substream->proc_info_entry = NULL;
611 	snd_info_free_entry(substream->proc_hw_params_entry);
612 	substream->proc_hw_params_entry = NULL;
613 	snd_info_free_entry(substream->proc_sw_params_entry);
614 	substream->proc_sw_params_entry = NULL;
615 	snd_info_free_entry(substream->proc_status_entry);
616 	substream->proc_status_entry = NULL;
617 	snd_info_free_entry(substream->proc_root);
618 	substream->proc_root = NULL;
619 	return 0;
620 }
621 #else /* !CONFIG_SND_VERBOSE_PROCFS */
622 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
623 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
624 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
625 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
626 #endif /* CONFIG_SND_VERBOSE_PROCFS */
627 
628 /**
629  * snd_pcm_new_stream - create a new PCM stream
630  * @pcm: the pcm instance
631  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
632  * @substream_count: the number of substreams
633  *
634  * Creates a new stream for the pcm.
635  * The corresponding stream on the pcm must have been empty before
636  * calling this, i.e. zero must be given to the argument of
637  * snd_pcm_new().
638  *
639  * Returns zero if successful, or a negative error code on failure.
640  */
641 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
642 {
643 	int idx, err;
644 	struct snd_pcm_str *pstr = &pcm->streams[stream];
645 	struct snd_pcm_substream *substream, *prev;
646 
647 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
648 	mutex_init(&pstr->oss.setup_mutex);
649 #endif
650 	pstr->stream = stream;
651 	pstr->pcm = pcm;
652 	pstr->substream_count = substream_count;
653 	if (substream_count > 0) {
654 		err = snd_pcm_stream_proc_init(pstr);
655 		if (err < 0) {
656 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
657 			return err;
658 		}
659 	}
660 	prev = NULL;
661 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
662 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
663 		if (substream == NULL) {
664 			snd_printk(KERN_ERR "Cannot allocate PCM substream\n");
665 			return -ENOMEM;
666 		}
667 		substream->pcm = pcm;
668 		substream->pstr = pstr;
669 		substream->number = idx;
670 		substream->stream = stream;
671 		sprintf(substream->name, "subdevice #%i", idx);
672 		substream->buffer_bytes_max = UINT_MAX;
673 		if (prev == NULL)
674 			pstr->substream = substream;
675 		else
676 			prev->next = substream;
677 		err = snd_pcm_substream_proc_init(substream);
678 		if (err < 0) {
679 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
680 			if (prev == NULL)
681 				pstr->substream = NULL;
682 			else
683 				prev->next = NULL;
684 			kfree(substream);
685 			return err;
686 		}
687 		substream->group = &substream->self_group;
688 		spin_lock_init(&substream->self_group.lock);
689 		INIT_LIST_HEAD(&substream->self_group.substreams);
690 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
691 		atomic_set(&substream->mmap_count, 0);
692 		prev = substream;
693 	}
694 	return 0;
695 }
696 
697 EXPORT_SYMBOL(snd_pcm_new_stream);
698 
699 /**
700  * snd_pcm_new - create a new PCM instance
701  * @card: the card instance
702  * @id: the id string
703  * @device: the device index (zero based)
704  * @playback_count: the number of substreams for playback
705  * @capture_count: the number of substreams for capture
706  * @rpcm: the pointer to store the new pcm instance
707  *
708  * Creates a new PCM instance.
709  *
710  * The pcm operators have to be set afterwards to the new instance
711  * via snd_pcm_set_ops().
712  *
713  * Returns zero if successful, or a negative error code on failure.
714  */
715 int snd_pcm_new(struct snd_card *card, const char *id, int device,
716 		int playback_count, int capture_count,
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 		snd_printk(KERN_ERR "Cannot allocate PCM\n");
734 		return -ENOMEM;
735 	}
736 	pcm->card = card;
737 	pcm->device = device;
738 	if (id)
739 		strlcpy(pcm->id, id, sizeof(pcm->id));
740 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
741 		snd_pcm_free(pcm);
742 		return err;
743 	}
744 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
745 		snd_pcm_free(pcm);
746 		return err;
747 	}
748 	mutex_init(&pcm->open_mutex);
749 	init_waitqueue_head(&pcm->open_wait);
750 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
751 		snd_pcm_free(pcm);
752 		return err;
753 	}
754 	if (rpcm)
755 		*rpcm = pcm;
756 	return 0;
757 }
758 
759 EXPORT_SYMBOL(snd_pcm_new);
760 
761 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
762 {
763 	struct snd_pcm_substream *substream, *substream_next;
764 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
765 	struct snd_pcm_oss_setup *setup, *setupn;
766 #endif
767 	substream = pstr->substream;
768 	while (substream) {
769 		substream_next = substream->next;
770 		snd_pcm_timer_done(substream);
771 		snd_pcm_substream_proc_done(substream);
772 		kfree(substream);
773 		substream = substream_next;
774 	}
775 	snd_pcm_stream_proc_done(pstr);
776 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
777 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
778 		setupn = setup->next;
779 		kfree(setup->task_name);
780 		kfree(setup);
781 	}
782 #endif
783 }
784 
785 static int snd_pcm_free(struct snd_pcm *pcm)
786 {
787 	struct snd_pcm_notify *notify;
788 
789 	if (!pcm)
790 		return 0;
791 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
792 		notify->n_unregister(pcm);
793 	}
794 	if (pcm->private_free)
795 		pcm->private_free(pcm);
796 	snd_pcm_lib_preallocate_free_for_all(pcm);
797 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
798 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
799 	kfree(pcm);
800 	return 0;
801 }
802 
803 static int snd_pcm_dev_free(struct snd_device *device)
804 {
805 	struct snd_pcm *pcm = device->device_data;
806 	return snd_pcm_free(pcm);
807 }
808 
809 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
810 			     struct file *file,
811 			     struct snd_pcm_substream **rsubstream)
812 {
813 	struct snd_pcm_str * pstr;
814 	struct snd_pcm_substream *substream;
815 	struct snd_pcm_runtime *runtime;
816 	struct snd_ctl_file *kctl;
817 	struct snd_card *card;
818 	int prefer_subdevice = -1;
819 	size_t size;
820 
821 	if (snd_BUG_ON(!pcm || !rsubstream))
822 		return -ENXIO;
823 	*rsubstream = NULL;
824 	pstr = &pcm->streams[stream];
825 	if (pstr->substream == NULL || pstr->substream_count == 0)
826 		return -ENODEV;
827 
828 	card = pcm->card;
829 	read_lock(&card->ctl_files_rwlock);
830 	list_for_each_entry(kctl, &card->ctl_files, list) {
831 		if (kctl->pid == task_pid(current)) {
832 			prefer_subdevice = kctl->prefer_pcm_subdevice;
833 			if (prefer_subdevice != -1)
834 				break;
835 		}
836 	}
837 	read_unlock(&card->ctl_files_rwlock);
838 
839 	switch (stream) {
840 	case SNDRV_PCM_STREAM_PLAYBACK:
841 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
842 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
843 				if (SUBSTREAM_BUSY(substream))
844 					return -EAGAIN;
845 			}
846 		}
847 		break;
848 	case SNDRV_PCM_STREAM_CAPTURE:
849 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
850 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
851 				if (SUBSTREAM_BUSY(substream))
852 					return -EAGAIN;
853 			}
854 		}
855 		break;
856 	default:
857 		return -EINVAL;
858 	}
859 
860 	if (file->f_flags & O_APPEND) {
861 		if (prefer_subdevice < 0) {
862 			if (pstr->substream_count > 1)
863 				return -EINVAL; /* must be unique */
864 			substream = pstr->substream;
865 		} else {
866 			for (substream = pstr->substream; substream;
867 			     substream = substream->next)
868 				if (substream->number == prefer_subdevice)
869 					break;
870 		}
871 		if (! substream)
872 			return -ENODEV;
873 		if (! SUBSTREAM_BUSY(substream))
874 			return -EBADFD;
875 		substream->ref_count++;
876 		*rsubstream = substream;
877 		return 0;
878 	}
879 
880 	if (prefer_subdevice >= 0) {
881 		for (substream = pstr->substream; substream; substream = substream->next)
882 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
883 				goto __ok;
884 	}
885 	for (substream = pstr->substream; substream; substream = substream->next)
886 		if (!SUBSTREAM_BUSY(substream))
887 			break;
888       __ok:
889 	if (substream == NULL)
890 		return -EAGAIN;
891 
892 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
893 	if (runtime == NULL)
894 		return -ENOMEM;
895 
896 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
897 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
898 	if (runtime->status == NULL) {
899 		kfree(runtime);
900 		return -ENOMEM;
901 	}
902 	memset((void*)runtime->status, 0, size);
903 
904 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
905 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
906 	if (runtime->control == NULL) {
907 		snd_free_pages((void*)runtime->status,
908 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
909 		kfree(runtime);
910 		return -ENOMEM;
911 	}
912 	memset((void*)runtime->control, 0, size);
913 
914 	init_waitqueue_head(&runtime->sleep);
915 	init_waitqueue_head(&runtime->tsleep);
916 
917 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
918 
919 	substream->runtime = runtime;
920 	substream->private_data = pcm->private_data;
921 	substream->ref_count = 1;
922 	substream->f_flags = file->f_flags;
923 	substream->pid = get_pid(task_pid(current));
924 	pstr->substream_opened++;
925 	*rsubstream = substream;
926 	return 0;
927 }
928 
929 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
930 {
931 	struct snd_pcm_runtime *runtime;
932 
933 	if (PCM_RUNTIME_CHECK(substream))
934 		return;
935 	runtime = substream->runtime;
936 	if (runtime->private_free != NULL)
937 		runtime->private_free(runtime);
938 	snd_free_pages((void*)runtime->status,
939 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
940 	snd_free_pages((void*)runtime->control,
941 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
942 	kfree(runtime->hw_constraints.rules);
943 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
944 	if (runtime->hwptr_log)
945 		kfree(runtime->hwptr_log);
946 #endif
947 	kfree(runtime);
948 	substream->runtime = NULL;
949 	put_pid(substream->pid);
950 	substream->pid = NULL;
951 	substream->pstr->substream_opened--;
952 }
953 
954 static ssize_t show_pcm_class(struct device *dev,
955 			      struct device_attribute *attr, char *buf)
956 {
957 	struct snd_pcm *pcm;
958 	const char *str;
959 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
960 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
961 		[SNDRV_PCM_CLASS_MULTI] = "multi",
962 		[SNDRV_PCM_CLASS_MODEM] = "modem",
963 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
964 	};
965 
966 	if (! (pcm = dev_get_drvdata(dev)) ||
967 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
968 		str = "none";
969 	else
970 		str = strs[pcm->dev_class];
971         return snprintf(buf, PAGE_SIZE, "%s\n", str);
972 }
973 
974 static struct device_attribute pcm_attrs =
975 	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
976 
977 static int snd_pcm_dev_register(struct snd_device *device)
978 {
979 	int cidx, err;
980 	struct snd_pcm_substream *substream;
981 	struct snd_pcm_notify *notify;
982 	char str[16];
983 	struct snd_pcm *pcm;
984 	struct device *dev;
985 
986 	if (snd_BUG_ON(!device || !device->device_data))
987 		return -ENXIO;
988 	pcm = device->device_data;
989 	mutex_lock(&register_mutex);
990 	err = snd_pcm_add(pcm);
991 	if (err) {
992 		mutex_unlock(&register_mutex);
993 		return err;
994 	}
995 	for (cidx = 0; cidx < 2; cidx++) {
996 		int devtype = -1;
997 		if (pcm->streams[cidx].substream == NULL)
998 			continue;
999 		switch (cidx) {
1000 		case SNDRV_PCM_STREAM_PLAYBACK:
1001 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1002 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1003 			break;
1004 		case SNDRV_PCM_STREAM_CAPTURE:
1005 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1006 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1007 			break;
1008 		}
1009 		/* device pointer to use, pcm->dev takes precedence if
1010 		 * it is assigned, otherwise fall back to card's device
1011 		 * if possible */
1012 		dev = pcm->dev;
1013 		if (!dev)
1014 			dev = snd_card_get_device_link(pcm->card);
1015 		/* register pcm */
1016 		err = snd_register_device_for_dev(devtype, pcm->card,
1017 						  pcm->device,
1018 						  &snd_pcm_f_ops[cidx],
1019 						  pcm, str, dev);
1020 		if (err < 0) {
1021 			list_del(&pcm->list);
1022 			mutex_unlock(&register_mutex);
1023 			return err;
1024 		}
1025 		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,
1026 					  &pcm_attrs);
1027 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1028 			snd_pcm_timer_init(substream);
1029 	}
1030 
1031 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1032 		notify->n_register(pcm);
1033 
1034 	mutex_unlock(&register_mutex);
1035 	return 0;
1036 }
1037 
1038 static int snd_pcm_dev_disconnect(struct snd_device *device)
1039 {
1040 	struct snd_pcm *pcm = device->device_data;
1041 	struct snd_pcm_notify *notify;
1042 	struct snd_pcm_substream *substream;
1043 	int cidx, devtype;
1044 
1045 	mutex_lock(&register_mutex);
1046 	if (list_empty(&pcm->list))
1047 		goto unlock;
1048 
1049 	list_del_init(&pcm->list);
1050 	for (cidx = 0; cidx < 2; cidx++)
1051 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1052 			if (substream->runtime)
1053 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1054 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1055 		notify->n_disconnect(pcm);
1056 	}
1057 	for (cidx = 0; cidx < 2; cidx++) {
1058 		devtype = -1;
1059 		switch (cidx) {
1060 		case SNDRV_PCM_STREAM_PLAYBACK:
1061 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1062 			break;
1063 		case SNDRV_PCM_STREAM_CAPTURE:
1064 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1065 			break;
1066 		}
1067 		snd_unregister_device(devtype, pcm->card, pcm->device);
1068 	}
1069  unlock:
1070 	mutex_unlock(&register_mutex);
1071 	return 0;
1072 }
1073 
1074 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1075 {
1076 	struct snd_pcm *pcm;
1077 
1078 	if (snd_BUG_ON(!notify ||
1079 		       !notify->n_register ||
1080 		       !notify->n_unregister ||
1081 		       !notify->n_disconnect))
1082 		return -EINVAL;
1083 	mutex_lock(&register_mutex);
1084 	if (nfree) {
1085 		list_del(&notify->list);
1086 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1087 			notify->n_unregister(pcm);
1088 	} else {
1089 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1090 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1091 			notify->n_register(pcm);
1092 	}
1093 	mutex_unlock(&register_mutex);
1094 	return 0;
1095 }
1096 
1097 EXPORT_SYMBOL(snd_pcm_notify);
1098 
1099 #ifdef CONFIG_PROC_FS
1100 /*
1101  *  Info interface
1102  */
1103 
1104 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1105 			      struct snd_info_buffer *buffer)
1106 {
1107 	struct snd_pcm *pcm;
1108 
1109 	mutex_lock(&register_mutex);
1110 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1111 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1112 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1113 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1114 			snd_iprintf(buffer, " : playback %i",
1115 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1116 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1117 			snd_iprintf(buffer, " : capture %i",
1118 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1119 		snd_iprintf(buffer, "\n");
1120 	}
1121 	mutex_unlock(&register_mutex);
1122 }
1123 
1124 static struct snd_info_entry *snd_pcm_proc_entry;
1125 
1126 static void snd_pcm_proc_init(void)
1127 {
1128 	struct snd_info_entry *entry;
1129 
1130 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1131 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1132 		if (snd_info_register(entry) < 0) {
1133 			snd_info_free_entry(entry);
1134 			entry = NULL;
1135 		}
1136 	}
1137 	snd_pcm_proc_entry = entry;
1138 }
1139 
1140 static void snd_pcm_proc_done(void)
1141 {
1142 	snd_info_free_entry(snd_pcm_proc_entry);
1143 }
1144 
1145 #else /* !CONFIG_PROC_FS */
1146 #define snd_pcm_proc_init()
1147 #define snd_pcm_proc_done()
1148 #endif /* CONFIG_PROC_FS */
1149 
1150 
1151 /*
1152  *  ENTRY functions
1153  */
1154 
1155 static int __init alsa_pcm_init(void)
1156 {
1157 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1158 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1159 	snd_pcm_proc_init();
1160 	return 0;
1161 }
1162 
1163 static void __exit alsa_pcm_exit(void)
1164 {
1165 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1166 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1167 	snd_pcm_proc_done();
1168 }
1169 
1170 module_init(alsa_pcm_init)
1171 module_exit(alsa_pcm_exit)
1172