xref: /linux/sound/core/pcm.c (revision 6288cf1e768ae73db5ddaaae54d85245cc1c2b56)
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/time.h>
25 #include <linux/mutex.h>
26 #include <sound/core.h>
27 #include <sound/minors.h>
28 #include <sound/pcm.h>
29 #include <sound/control.h>
30 #include <sound/info.h>
31 
32 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
33 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
34 MODULE_LICENSE("GPL");
35 
36 static LIST_HEAD(snd_pcm_devices);
37 static LIST_HEAD(snd_pcm_notify_list);
38 static DEFINE_MUTEX(register_mutex);
39 
40 static int snd_pcm_free(struct snd_pcm *pcm);
41 static int snd_pcm_dev_free(struct snd_device *device);
42 static int snd_pcm_dev_register(struct snd_device *device);
43 static int snd_pcm_dev_disconnect(struct snd_device *device);
44 
45 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
46 {
47 	struct snd_pcm *pcm;
48 
49 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
50 		if (pcm->card == card && pcm->device == device)
51 			return pcm;
52 	}
53 	return NULL;
54 }
55 
56 static int snd_pcm_next(struct snd_card *card, int device)
57 {
58 	struct snd_pcm *pcm;
59 
60 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
61 		if (pcm->card == card && pcm->device > device)
62 			return pcm->device;
63 		else if (pcm->card->number > card->number)
64 			return -1;
65 	}
66 	return -1;
67 }
68 
69 static int snd_pcm_add(struct snd_pcm *newpcm)
70 {
71 	struct snd_pcm *pcm;
72 
73 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
74 		if (pcm->card == newpcm->card && pcm->device == newpcm->device)
75 			return -EBUSY;
76 		if (pcm->card->number > newpcm->card->number ||
77 				(pcm->card == newpcm->card &&
78 				pcm->device > newpcm->device)) {
79 			list_add(&newpcm->list, pcm->list.prev);
80 			return 0;
81 		}
82 	}
83 	list_add_tail(&newpcm->list, &snd_pcm_devices);
84 	return 0;
85 }
86 
87 static int snd_pcm_control_ioctl(struct snd_card *card,
88 				 struct snd_ctl_file *control,
89 				 unsigned int cmd, unsigned long arg)
90 {
91 	switch (cmd) {
92 	case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
93 		{
94 			int device;
95 
96 			if (get_user(device, (int __user *)arg))
97 				return -EFAULT;
98 			mutex_lock(&register_mutex);
99 			device = snd_pcm_next(card, device);
100 			mutex_unlock(&register_mutex);
101 			if (put_user(device, (int __user *)arg))
102 				return -EFAULT;
103 			return 0;
104 		}
105 	case SNDRV_CTL_IOCTL_PCM_INFO:
106 		{
107 			struct snd_pcm_info __user *info;
108 			unsigned int device, subdevice;
109 			int stream;
110 			struct snd_pcm *pcm;
111 			struct snd_pcm_str *pstr;
112 			struct snd_pcm_substream *substream;
113 			int err;
114 
115 			info = (struct snd_pcm_info __user *)arg;
116 			if (get_user(device, &info->device))
117 				return -EFAULT;
118 			if (get_user(stream, &info->stream))
119 				return -EFAULT;
120 			if (stream < 0 || stream > 1)
121 				return -EINVAL;
122 			if (get_user(subdevice, &info->subdevice))
123 				return -EFAULT;
124 			mutex_lock(&register_mutex);
125 			pcm = snd_pcm_get(card, device);
126 			if (pcm == NULL) {
127 				err = -ENXIO;
128 				goto _error;
129 			}
130 			pstr = &pcm->streams[stream];
131 			if (pstr->substream_count == 0) {
132 				err = -ENOENT;
133 				goto _error;
134 			}
135 			if (subdevice >= pstr->substream_count) {
136 				err = -ENXIO;
137 				goto _error;
138 			}
139 			for (substream = pstr->substream; substream;
140 			     substream = substream->next)
141 				if (substream->number == (int)subdevice)
142 					break;
143 			if (substream == NULL) {
144 				err = -ENXIO;
145 				goto _error;
146 			}
147 			err = snd_pcm_info_user(substream, info);
148 		_error:
149 			mutex_unlock(&register_mutex);
150 			return err;
151 		}
152 	case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
153 		{
154 			int val;
155 
156 			if (get_user(val, (int __user *)arg))
157 				return -EFAULT;
158 			control->prefer_pcm_subdevice = val;
159 			return 0;
160 		}
161 	}
162 	return -ENOIOCTLCMD;
163 }
164 
165 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
166 
167 static char *snd_pcm_format_names[] = {
168 	FORMAT(S8),
169 	FORMAT(U8),
170 	FORMAT(S16_LE),
171 	FORMAT(S16_BE),
172 	FORMAT(U16_LE),
173 	FORMAT(U16_BE),
174 	FORMAT(S24_LE),
175 	FORMAT(S24_BE),
176 	FORMAT(U24_LE),
177 	FORMAT(U24_BE),
178 	FORMAT(S32_LE),
179 	FORMAT(S32_BE),
180 	FORMAT(U32_LE),
181 	FORMAT(U32_BE),
182 	FORMAT(FLOAT_LE),
183 	FORMAT(FLOAT_BE),
184 	FORMAT(FLOAT64_LE),
185 	FORMAT(FLOAT64_BE),
186 	FORMAT(IEC958_SUBFRAME_LE),
187 	FORMAT(IEC958_SUBFRAME_BE),
188 	FORMAT(MU_LAW),
189 	FORMAT(A_LAW),
190 	FORMAT(IMA_ADPCM),
191 	FORMAT(MPEG),
192 	FORMAT(GSM),
193 	FORMAT(SPECIAL),
194 	FORMAT(S24_3LE),
195 	FORMAT(S24_3BE),
196 	FORMAT(U24_3LE),
197 	FORMAT(U24_3BE),
198 	FORMAT(S20_3LE),
199 	FORMAT(S20_3BE),
200 	FORMAT(U20_3LE),
201 	FORMAT(U20_3BE),
202 	FORMAT(S18_3LE),
203 	FORMAT(S18_3BE),
204 	FORMAT(U18_3LE),
205 	FORMAT(U18_3BE),
206 	FORMAT(G723_24),
207 	FORMAT(G723_24_1B),
208 	FORMAT(G723_40),
209 	FORMAT(G723_40_1B),
210 };
211 
212 const char *snd_pcm_format_name(snd_pcm_format_t format)
213 {
214 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
215 		return "Unknown";
216 	return snd_pcm_format_names[(__force unsigned int)format];
217 }
218 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
219 
220 #ifdef CONFIG_SND_VERBOSE_PROCFS
221 
222 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
223 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
224 #define READY(v) [SNDRV_PCM_READY_##v] = #v
225 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
226 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
227 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
228 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
229 #define START(v) [SNDRV_PCM_START_##v] = #v
230 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
231 
232 static char *snd_pcm_stream_names[] = {
233 	STREAM(PLAYBACK),
234 	STREAM(CAPTURE),
235 };
236 
237 static char *snd_pcm_state_names[] = {
238 	STATE(OPEN),
239 	STATE(SETUP),
240 	STATE(PREPARED),
241 	STATE(RUNNING),
242 	STATE(XRUN),
243 	STATE(DRAINING),
244 	STATE(PAUSED),
245 	STATE(SUSPENDED),
246 };
247 
248 static char *snd_pcm_access_names[] = {
249 	ACCESS(MMAP_INTERLEAVED),
250 	ACCESS(MMAP_NONINTERLEAVED),
251 	ACCESS(MMAP_COMPLEX),
252 	ACCESS(RW_INTERLEAVED),
253 	ACCESS(RW_NONINTERLEAVED),
254 };
255 
256 static char *snd_pcm_subformat_names[] = {
257 	SUBFORMAT(STD),
258 };
259 
260 static char *snd_pcm_tstamp_mode_names[] = {
261 	TSTAMP(NONE),
262 	TSTAMP(ENABLE),
263 };
264 
265 static const char *snd_pcm_stream_name(int stream)
266 {
267 	return snd_pcm_stream_names[stream];
268 }
269 
270 static const char *snd_pcm_access_name(snd_pcm_access_t access)
271 {
272 	return snd_pcm_access_names[(__force int)access];
273 }
274 
275 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
276 {
277 	return snd_pcm_subformat_names[(__force int)subformat];
278 }
279 
280 static const char *snd_pcm_tstamp_mode_name(int mode)
281 {
282 	return snd_pcm_tstamp_mode_names[mode];
283 }
284 
285 static const char *snd_pcm_state_name(snd_pcm_state_t state)
286 {
287 	return snd_pcm_state_names[(__force int)state];
288 }
289 
290 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
291 #include <linux/soundcard.h>
292 
293 static const char *snd_pcm_oss_format_name(int format)
294 {
295 	switch (format) {
296 	case AFMT_MU_LAW:
297 		return "MU_LAW";
298 	case AFMT_A_LAW:
299 		return "A_LAW";
300 	case AFMT_IMA_ADPCM:
301 		return "IMA_ADPCM";
302 	case AFMT_U8:
303 		return "U8";
304 	case AFMT_S16_LE:
305 		return "S16_LE";
306 	case AFMT_S16_BE:
307 		return "S16_BE";
308 	case AFMT_S8:
309 		return "S8";
310 	case AFMT_U16_LE:
311 		return "U16_LE";
312 	case AFMT_U16_BE:
313 		return "U16_BE";
314 	case AFMT_MPEG:
315 		return "MPEG";
316 	default:
317 		return "unknown";
318 	}
319 }
320 #endif
321 
322 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
323 				   struct snd_info_buffer *buffer)
324 {
325 	struct snd_pcm_info *info;
326 	int err;
327 
328 	if (! substream)
329 		return;
330 
331 	info = kmalloc(sizeof(*info), GFP_KERNEL);
332 	if (! info) {
333 		printk(KERN_DEBUG "snd_pcm_proc_info_read: cannot malloc\n");
334 		return;
335 	}
336 
337 	err = snd_pcm_info(substream, info);
338 	if (err < 0) {
339 		snd_iprintf(buffer, "error %d\n", err);
340 		kfree(info);
341 		return;
342 	}
343 	snd_iprintf(buffer, "card: %d\n", info->card);
344 	snd_iprintf(buffer, "device: %d\n", info->device);
345 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
346 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
347 	snd_iprintf(buffer, "id: %s\n", info->id);
348 	snd_iprintf(buffer, "name: %s\n", info->name);
349 	snd_iprintf(buffer, "subname: %s\n", info->subname);
350 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
351 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
352 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
353 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
354 	kfree(info);
355 }
356 
357 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
358 					  struct snd_info_buffer *buffer)
359 {
360 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
361 			       buffer);
362 }
363 
364 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
365 					     struct snd_info_buffer *buffer)
366 {
367 	snd_pcm_proc_info_read(entry->private_data, buffer);
368 }
369 
370 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
371 						  struct snd_info_buffer *buffer)
372 {
373 	struct snd_pcm_substream *substream = entry->private_data;
374 	struct snd_pcm_runtime *runtime;
375 
376 	mutex_lock(&substream->pcm->open_mutex);
377 	runtime = substream->runtime;
378 	if (!runtime) {
379 		snd_iprintf(buffer, "closed\n");
380 		goto unlock;
381 	}
382 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
383 		snd_iprintf(buffer, "no setup\n");
384 		goto unlock;
385 	}
386 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
387 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
388 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
389 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
390 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
391 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
392 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
393 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
394 	if (substream->oss.oss) {
395 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
396 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
397 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
398 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
399 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
400 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
401 	}
402 #endif
403  unlock:
404 	mutex_unlock(&substream->pcm->open_mutex);
405 }
406 
407 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
408 						  struct snd_info_buffer *buffer)
409 {
410 	struct snd_pcm_substream *substream = entry->private_data;
411 	struct snd_pcm_runtime *runtime;
412 
413 	mutex_lock(&substream->pcm->open_mutex);
414 	runtime = substream->runtime;
415 	if (!runtime) {
416 		snd_iprintf(buffer, "closed\n");
417 		goto unlock;
418 	}
419 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
420 		snd_iprintf(buffer, "no setup\n");
421 		goto unlock;
422 	}
423 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
424 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
425 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
426 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
427 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
428 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
429 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
430 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
431  unlock:
432 	mutex_unlock(&substream->pcm->open_mutex);
433 }
434 
435 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
436 					       struct snd_info_buffer *buffer)
437 {
438 	struct snd_pcm_substream *substream = entry->private_data;
439 	struct snd_pcm_runtime *runtime;
440 	struct snd_pcm_status status;
441 	int err;
442 
443 	mutex_lock(&substream->pcm->open_mutex);
444 	runtime = substream->runtime;
445 	if (!runtime) {
446 		snd_iprintf(buffer, "closed\n");
447 		goto unlock;
448 	}
449 	memset(&status, 0, sizeof(status));
450 	err = snd_pcm_status(substream, &status);
451 	if (err < 0) {
452 		snd_iprintf(buffer, "error %d\n", err);
453 		goto unlock;
454 	}
455 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
456 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
457 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
458 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
459 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
460 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
461 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
462 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
463 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
464 	snd_iprintf(buffer, "-----\n");
465 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
466 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
467  unlock:
468 	mutex_unlock(&substream->pcm->open_mutex);
469 }
470 
471 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
472 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
473 				    struct snd_info_buffer *buffer)
474 {
475 	struct snd_pcm_str *pstr = entry->private_data;
476 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
477 }
478 
479 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
480 				     struct snd_info_buffer *buffer)
481 {
482 	struct snd_pcm_str *pstr = entry->private_data;
483 	char line[64];
484 	if (!snd_info_get_line(buffer, line, sizeof(line)))
485 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
486 }
487 #endif
488 
489 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
490 {
491 	struct snd_pcm *pcm = pstr->pcm;
492 	struct snd_info_entry *entry;
493 	char name[16];
494 
495 	sprintf(name, "pcm%i%c", pcm->device,
496 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
497 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
498 		return -ENOMEM;
499 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
500 	if (snd_info_register(entry) < 0) {
501 		snd_info_free_entry(entry);
502 		return -ENOMEM;
503 	}
504 	pstr->proc_root = entry;
505 
506 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
507 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
508 		if (snd_info_register(entry) < 0) {
509 			snd_info_free_entry(entry);
510 			entry = NULL;
511 		}
512 	}
513 	pstr->proc_info_entry = entry;
514 
515 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
516 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
517 						pstr->proc_root)) != NULL) {
518 		entry->c.text.read = snd_pcm_xrun_debug_read;
519 		entry->c.text.write = snd_pcm_xrun_debug_write;
520 		entry->mode |= S_IWUSR;
521 		entry->private_data = pstr;
522 		if (snd_info_register(entry) < 0) {
523 			snd_info_free_entry(entry);
524 			entry = NULL;
525 		}
526 	}
527 	pstr->proc_xrun_debug_entry = entry;
528 #endif
529 	return 0;
530 }
531 
532 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
533 {
534 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
535 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
536 	pstr->proc_xrun_debug_entry = NULL;
537 #endif
538 	snd_info_free_entry(pstr->proc_info_entry);
539 	pstr->proc_info_entry = NULL;
540 	snd_info_free_entry(pstr->proc_root);
541 	pstr->proc_root = NULL;
542 	return 0;
543 }
544 
545 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
546 {
547 	struct snd_info_entry *entry;
548 	struct snd_card *card;
549 	char name[16];
550 
551 	card = substream->pcm->card;
552 
553 	sprintf(name, "sub%i", substream->number);
554 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
555 		return -ENOMEM;
556 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
557 	if (snd_info_register(entry) < 0) {
558 		snd_info_free_entry(entry);
559 		return -ENOMEM;
560 	}
561 	substream->proc_root = entry;
562 
563 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
564 		snd_info_set_text_ops(entry, substream,
565 				      snd_pcm_substream_proc_info_read);
566 		if (snd_info_register(entry) < 0) {
567 			snd_info_free_entry(entry);
568 			entry = NULL;
569 		}
570 	}
571 	substream->proc_info_entry = entry;
572 
573 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
574 		snd_info_set_text_ops(entry, substream,
575 				      snd_pcm_substream_proc_hw_params_read);
576 		if (snd_info_register(entry) < 0) {
577 			snd_info_free_entry(entry);
578 			entry = NULL;
579 		}
580 	}
581 	substream->proc_hw_params_entry = entry;
582 
583 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
584 		snd_info_set_text_ops(entry, substream,
585 				      snd_pcm_substream_proc_sw_params_read);
586 		if (snd_info_register(entry) < 0) {
587 			snd_info_free_entry(entry);
588 			entry = NULL;
589 		}
590 	}
591 	substream->proc_sw_params_entry = entry;
592 
593 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
594 		snd_info_set_text_ops(entry, substream,
595 				      snd_pcm_substream_proc_status_read);
596 		if (snd_info_register(entry) < 0) {
597 			snd_info_free_entry(entry);
598 			entry = NULL;
599 		}
600 	}
601 	substream->proc_status_entry = entry;
602 
603 	return 0;
604 }
605 
606 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
607 {
608 	snd_info_free_entry(substream->proc_info_entry);
609 	substream->proc_info_entry = NULL;
610 	snd_info_free_entry(substream->proc_hw_params_entry);
611 	substream->proc_hw_params_entry = NULL;
612 	snd_info_free_entry(substream->proc_sw_params_entry);
613 	substream->proc_sw_params_entry = NULL;
614 	snd_info_free_entry(substream->proc_status_entry);
615 	substream->proc_status_entry = NULL;
616 	snd_info_free_entry(substream->proc_root);
617 	substream->proc_root = NULL;
618 	return 0;
619 }
620 #else /* !CONFIG_SND_VERBOSE_PROCFS */
621 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
622 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
623 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
624 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
625 #endif /* CONFIG_SND_VERBOSE_PROCFS */
626 
627 /**
628  * snd_pcm_new_stream - create a new PCM stream
629  * @pcm: the pcm instance
630  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
631  * @substream_count: the number of substreams
632  *
633  * Creates a new stream for the pcm.
634  * The corresponding stream on the pcm must have been empty before
635  * calling this, i.e. zero must be given to the argument of
636  * snd_pcm_new().
637  *
638  * Returns zero if successful, or a negative error code on failure.
639  */
640 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
641 {
642 	int idx, err;
643 	struct snd_pcm_str *pstr = &pcm->streams[stream];
644 	struct snd_pcm_substream *substream, *prev;
645 
646 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
647 	mutex_init(&pstr->oss.setup_mutex);
648 #endif
649 	pstr->stream = stream;
650 	pstr->pcm = pcm;
651 	pstr->substream_count = substream_count;
652 	if (substream_count > 0) {
653 		err = snd_pcm_stream_proc_init(pstr);
654 		if (err < 0) {
655 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
656 			return err;
657 		}
658 	}
659 	prev = NULL;
660 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
661 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
662 		if (substream == NULL) {
663 			snd_printk(KERN_ERR "Cannot allocate PCM substream\n");
664 			return -ENOMEM;
665 		}
666 		substream->pcm = pcm;
667 		substream->pstr = pstr;
668 		substream->number = idx;
669 		substream->stream = stream;
670 		sprintf(substream->name, "subdevice #%i", idx);
671 		substream->buffer_bytes_max = UINT_MAX;
672 		if (prev == NULL)
673 			pstr->substream = substream;
674 		else
675 			prev->next = substream;
676 		err = snd_pcm_substream_proc_init(substream);
677 		if (err < 0) {
678 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
679 			if (prev == NULL)
680 				pstr->substream = NULL;
681 			else
682 				prev->next = NULL;
683 			kfree(substream);
684 			return err;
685 		}
686 		substream->group = &substream->self_group;
687 		spin_lock_init(&substream->self_group.lock);
688 		INIT_LIST_HEAD(&substream->self_group.substreams);
689 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
690 		atomic_set(&substream->mmap_count, 0);
691 		prev = substream;
692 	}
693 	return 0;
694 }
695 
696 EXPORT_SYMBOL(snd_pcm_new_stream);
697 
698 /**
699  * snd_pcm_new - create a new PCM instance
700  * @card: the card instance
701  * @id: the id string
702  * @device: the device index (zero based)
703  * @playback_count: the number of substreams for playback
704  * @capture_count: the number of substreams for capture
705  * @rpcm: the pointer to store the new pcm instance
706  *
707  * Creates a new PCM instance.
708  *
709  * The pcm operators have to be set afterwards to the new instance
710  * via snd_pcm_set_ops().
711  *
712  * Returns zero if successful, or a negative error code on failure.
713  */
714 int snd_pcm_new(struct snd_card *card, const char *id, int device,
715 		int playback_count, int capture_count,
716 	        struct snd_pcm ** rpcm)
717 {
718 	struct snd_pcm *pcm;
719 	int err;
720 	static struct snd_device_ops ops = {
721 		.dev_free = snd_pcm_dev_free,
722 		.dev_register =	snd_pcm_dev_register,
723 		.dev_disconnect = snd_pcm_dev_disconnect,
724 	};
725 
726 	if (snd_BUG_ON(!card))
727 		return -ENXIO;
728 	if (rpcm)
729 		*rpcm = NULL;
730 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
731 	if (pcm == NULL) {
732 		snd_printk(KERN_ERR "Cannot allocate PCM\n");
733 		return -ENOMEM;
734 	}
735 	pcm->card = card;
736 	pcm->device = device;
737 	if (id)
738 		strlcpy(pcm->id, id, sizeof(pcm->id));
739 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
740 		snd_pcm_free(pcm);
741 		return err;
742 	}
743 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
744 		snd_pcm_free(pcm);
745 		return err;
746 	}
747 	mutex_init(&pcm->open_mutex);
748 	init_waitqueue_head(&pcm->open_wait);
749 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
750 		snd_pcm_free(pcm);
751 		return err;
752 	}
753 	if (rpcm)
754 		*rpcm = pcm;
755 	return 0;
756 }
757 
758 EXPORT_SYMBOL(snd_pcm_new);
759 
760 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
761 {
762 	struct snd_pcm_substream *substream, *substream_next;
763 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
764 	struct snd_pcm_oss_setup *setup, *setupn;
765 #endif
766 	substream = pstr->substream;
767 	while (substream) {
768 		substream_next = substream->next;
769 		snd_pcm_timer_done(substream);
770 		snd_pcm_substream_proc_done(substream);
771 		kfree(substream);
772 		substream = substream_next;
773 	}
774 	snd_pcm_stream_proc_done(pstr);
775 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
776 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
777 		setupn = setup->next;
778 		kfree(setup->task_name);
779 		kfree(setup);
780 	}
781 #endif
782 }
783 
784 static int snd_pcm_free(struct snd_pcm *pcm)
785 {
786 	struct snd_pcm_notify *notify;
787 
788 	if (!pcm)
789 		return 0;
790 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
791 		notify->n_unregister(pcm);
792 	}
793 	if (pcm->private_free)
794 		pcm->private_free(pcm);
795 	snd_pcm_lib_preallocate_free_for_all(pcm);
796 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
797 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
798 	kfree(pcm);
799 	return 0;
800 }
801 
802 static int snd_pcm_dev_free(struct snd_device *device)
803 {
804 	struct snd_pcm *pcm = device->device_data;
805 	return snd_pcm_free(pcm);
806 }
807 
808 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
809 			     struct file *file,
810 			     struct snd_pcm_substream **rsubstream)
811 {
812 	struct snd_pcm_str * pstr;
813 	struct snd_pcm_substream *substream;
814 	struct snd_pcm_runtime *runtime;
815 	struct snd_ctl_file *kctl;
816 	struct snd_card *card;
817 	int prefer_subdevice = -1;
818 	size_t size;
819 
820 	if (snd_BUG_ON(!pcm || !rsubstream))
821 		return -ENXIO;
822 	*rsubstream = NULL;
823 	pstr = &pcm->streams[stream];
824 	if (pstr->substream == NULL || pstr->substream_count == 0)
825 		return -ENODEV;
826 
827 	card = pcm->card;
828 	read_lock(&card->ctl_files_rwlock);
829 	list_for_each_entry(kctl, &card->ctl_files, list) {
830 		if (kctl->pid == task_pid(current)) {
831 			prefer_subdevice = kctl->prefer_pcm_subdevice;
832 			if (prefer_subdevice != -1)
833 				break;
834 		}
835 	}
836 	read_unlock(&card->ctl_files_rwlock);
837 
838 	switch (stream) {
839 	case SNDRV_PCM_STREAM_PLAYBACK:
840 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
841 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
842 				if (SUBSTREAM_BUSY(substream))
843 					return -EAGAIN;
844 			}
845 		}
846 		break;
847 	case SNDRV_PCM_STREAM_CAPTURE:
848 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
849 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
850 				if (SUBSTREAM_BUSY(substream))
851 					return -EAGAIN;
852 			}
853 		}
854 		break;
855 	default:
856 		return -EINVAL;
857 	}
858 
859 	if (file->f_flags & O_APPEND) {
860 		if (prefer_subdevice < 0) {
861 			if (pstr->substream_count > 1)
862 				return -EINVAL; /* must be unique */
863 			substream = pstr->substream;
864 		} else {
865 			for (substream = pstr->substream; substream;
866 			     substream = substream->next)
867 				if (substream->number == prefer_subdevice)
868 					break;
869 		}
870 		if (! substream)
871 			return -ENODEV;
872 		if (! SUBSTREAM_BUSY(substream))
873 			return -EBADFD;
874 		substream->ref_count++;
875 		*rsubstream = substream;
876 		return 0;
877 	}
878 
879 	if (prefer_subdevice >= 0) {
880 		for (substream = pstr->substream; substream; substream = substream->next)
881 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
882 				goto __ok;
883 	}
884 	for (substream = pstr->substream; substream; substream = substream->next)
885 		if (!SUBSTREAM_BUSY(substream))
886 			break;
887       __ok:
888 	if (substream == NULL)
889 		return -EAGAIN;
890 
891 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
892 	if (runtime == NULL)
893 		return -ENOMEM;
894 
895 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
896 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
897 	if (runtime->status == NULL) {
898 		kfree(runtime);
899 		return -ENOMEM;
900 	}
901 	memset((void*)runtime->status, 0, size);
902 
903 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
904 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
905 	if (runtime->control == NULL) {
906 		snd_free_pages((void*)runtime->status,
907 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
908 		kfree(runtime);
909 		return -ENOMEM;
910 	}
911 	memset((void*)runtime->control, 0, size);
912 
913 	init_waitqueue_head(&runtime->sleep);
914 	init_waitqueue_head(&runtime->tsleep);
915 
916 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
917 
918 	substream->runtime = runtime;
919 	substream->private_data = pcm->private_data;
920 	substream->ref_count = 1;
921 	substream->f_flags = file->f_flags;
922 	substream->pid = get_pid(task_pid(current));
923 	pstr->substream_opened++;
924 	*rsubstream = substream;
925 	return 0;
926 }
927 
928 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
929 {
930 	struct snd_pcm_runtime *runtime;
931 
932 	if (PCM_RUNTIME_CHECK(substream))
933 		return;
934 	runtime = substream->runtime;
935 	if (runtime->private_free != NULL)
936 		runtime->private_free(runtime);
937 	snd_free_pages((void*)runtime->status,
938 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
939 	snd_free_pages((void*)runtime->control,
940 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
941 	kfree(runtime->hw_constraints.rules);
942 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
943 	if (runtime->hwptr_log)
944 		kfree(runtime->hwptr_log);
945 #endif
946 	kfree(runtime);
947 	substream->runtime = NULL;
948 	put_pid(substream->pid);
949 	substream->pid = NULL;
950 	substream->pstr->substream_opened--;
951 }
952 
953 static ssize_t show_pcm_class(struct device *dev,
954 			      struct device_attribute *attr, char *buf)
955 {
956 	struct snd_pcm *pcm;
957 	const char *str;
958 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
959 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
960 		[SNDRV_PCM_CLASS_MULTI] = "multi",
961 		[SNDRV_PCM_CLASS_MODEM] = "modem",
962 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
963 	};
964 
965 	if (! (pcm = dev_get_drvdata(dev)) ||
966 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
967 		str = "none";
968 	else
969 		str = strs[pcm->dev_class];
970         return snprintf(buf, PAGE_SIZE, "%s\n", str);
971 }
972 
973 static struct device_attribute pcm_attrs =
974 	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
975 
976 static int snd_pcm_dev_register(struct snd_device *device)
977 {
978 	int cidx, err;
979 	struct snd_pcm_substream *substream;
980 	struct snd_pcm_notify *notify;
981 	char str[16];
982 	struct snd_pcm *pcm;
983 	struct device *dev;
984 
985 	if (snd_BUG_ON(!device || !device->device_data))
986 		return -ENXIO;
987 	pcm = device->device_data;
988 	mutex_lock(&register_mutex);
989 	err = snd_pcm_add(pcm);
990 	if (err) {
991 		mutex_unlock(&register_mutex);
992 		return err;
993 	}
994 	for (cidx = 0; cidx < 2; cidx++) {
995 		int devtype = -1;
996 		if (pcm->streams[cidx].substream == NULL)
997 			continue;
998 		switch (cidx) {
999 		case SNDRV_PCM_STREAM_PLAYBACK:
1000 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1001 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1002 			break;
1003 		case SNDRV_PCM_STREAM_CAPTURE:
1004 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1005 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1006 			break;
1007 		}
1008 		/* device pointer to use, pcm->dev takes precedence if
1009 		 * it is assigned, otherwise fall back to card's device
1010 		 * if possible */
1011 		dev = pcm->dev;
1012 		if (!dev)
1013 			dev = snd_card_get_device_link(pcm->card);
1014 		/* register pcm */
1015 		err = snd_register_device_for_dev(devtype, pcm->card,
1016 						  pcm->device,
1017 						  &snd_pcm_f_ops[cidx],
1018 						  pcm, str, dev);
1019 		if (err < 0) {
1020 			list_del(&pcm->list);
1021 			mutex_unlock(&register_mutex);
1022 			return err;
1023 		}
1024 		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,
1025 					  &pcm_attrs);
1026 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1027 			snd_pcm_timer_init(substream);
1028 	}
1029 
1030 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1031 		notify->n_register(pcm);
1032 
1033 	mutex_unlock(&register_mutex);
1034 	return 0;
1035 }
1036 
1037 static int snd_pcm_dev_disconnect(struct snd_device *device)
1038 {
1039 	struct snd_pcm *pcm = device->device_data;
1040 	struct snd_pcm_notify *notify;
1041 	struct snd_pcm_substream *substream;
1042 	int cidx, devtype;
1043 
1044 	mutex_lock(&register_mutex);
1045 	if (list_empty(&pcm->list))
1046 		goto unlock;
1047 
1048 	list_del_init(&pcm->list);
1049 	for (cidx = 0; cidx < 2; cidx++)
1050 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1051 			if (substream->runtime)
1052 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1053 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1054 		notify->n_disconnect(pcm);
1055 	}
1056 	for (cidx = 0; cidx < 2; cidx++) {
1057 		devtype = -1;
1058 		switch (cidx) {
1059 		case SNDRV_PCM_STREAM_PLAYBACK:
1060 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1061 			break;
1062 		case SNDRV_PCM_STREAM_CAPTURE:
1063 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1064 			break;
1065 		}
1066 		snd_unregister_device(devtype, pcm->card, pcm->device);
1067 	}
1068  unlock:
1069 	mutex_unlock(&register_mutex);
1070 	return 0;
1071 }
1072 
1073 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1074 {
1075 	struct snd_pcm *pcm;
1076 
1077 	if (snd_BUG_ON(!notify ||
1078 		       !notify->n_register ||
1079 		       !notify->n_unregister ||
1080 		       !notify->n_disconnect))
1081 		return -EINVAL;
1082 	mutex_lock(&register_mutex);
1083 	if (nfree) {
1084 		list_del(&notify->list);
1085 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1086 			notify->n_unregister(pcm);
1087 	} else {
1088 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1089 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1090 			notify->n_register(pcm);
1091 	}
1092 	mutex_unlock(&register_mutex);
1093 	return 0;
1094 }
1095 
1096 EXPORT_SYMBOL(snd_pcm_notify);
1097 
1098 #ifdef CONFIG_PROC_FS
1099 /*
1100  *  Info interface
1101  */
1102 
1103 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1104 			      struct snd_info_buffer *buffer)
1105 {
1106 	struct snd_pcm *pcm;
1107 
1108 	mutex_lock(&register_mutex);
1109 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1110 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1111 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1112 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1113 			snd_iprintf(buffer, " : playback %i",
1114 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1115 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1116 			snd_iprintf(buffer, " : capture %i",
1117 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1118 		snd_iprintf(buffer, "\n");
1119 	}
1120 	mutex_unlock(&register_mutex);
1121 }
1122 
1123 static struct snd_info_entry *snd_pcm_proc_entry;
1124 
1125 static void snd_pcm_proc_init(void)
1126 {
1127 	struct snd_info_entry *entry;
1128 
1129 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1130 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1131 		if (snd_info_register(entry) < 0) {
1132 			snd_info_free_entry(entry);
1133 			entry = NULL;
1134 		}
1135 	}
1136 	snd_pcm_proc_entry = entry;
1137 }
1138 
1139 static void snd_pcm_proc_done(void)
1140 {
1141 	snd_info_free_entry(snd_pcm_proc_entry);
1142 }
1143 
1144 #else /* !CONFIG_PROC_FS */
1145 #define snd_pcm_proc_init()
1146 #define snd_pcm_proc_done()
1147 #endif /* CONFIG_PROC_FS */
1148 
1149 
1150 /*
1151  *  ENTRY functions
1152  */
1153 
1154 static int __init alsa_pcm_init(void)
1155 {
1156 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1157 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1158 	snd_pcm_proc_init();
1159 	return 0;
1160 }
1161 
1162 static void __exit alsa_pcm_exit(void)
1163 {
1164 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1165 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1166 	snd_pcm_proc_done();
1167 }
1168 
1169 module_init(alsa_pcm_init)
1170 module_exit(alsa_pcm_exit)
1171