xref: /linux/sound/core/pcm.c (revision 606b2f490fb80e55d05cf0e6cec0b6c0ff0fc18f)
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 (format >= ARRAY_SIZE(snd_pcm_format_names))
215 		return "Unknown";
216 	return snd_pcm_format_names[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[access];
273 }
274 
275 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
276 {
277 	return snd_pcm_subformat_names[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[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((struct snd_pcm_substream *)entry->private_data,
368 			       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 = substream->runtime;
376 	if (!runtime) {
377 		snd_iprintf(buffer, "closed\n");
378 		return;
379 	}
380 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
381 		snd_iprintf(buffer, "no setup\n");
382 		return;
383 	}
384 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
385 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
386 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
387 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
388 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
389 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
390 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
391 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
392 	if (substream->oss.oss) {
393 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
394 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
395 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
396 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
397 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
398 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
399 	}
400 #endif
401 }
402 
403 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
404 						  struct snd_info_buffer *buffer)
405 {
406 	struct snd_pcm_substream *substream = entry->private_data;
407 	struct snd_pcm_runtime *runtime = substream->runtime;
408 	if (!runtime) {
409 		snd_iprintf(buffer, "closed\n");
410 		return;
411 	}
412 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
413 		snd_iprintf(buffer, "no setup\n");
414 		return;
415 	}
416 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
417 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
418 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
419 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
420 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
421 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
422 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
423 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
424 }
425 
426 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
427 					       struct snd_info_buffer *buffer)
428 {
429 	struct snd_pcm_substream *substream = entry->private_data;
430 	struct snd_pcm_runtime *runtime = substream->runtime;
431 	struct snd_pcm_status status;
432 	int err;
433 	if (!runtime) {
434 		snd_iprintf(buffer, "closed\n");
435 		return;
436 	}
437 	memset(&status, 0, sizeof(status));
438 	err = snd_pcm_status(substream, &status);
439 	if (err < 0) {
440 		snd_iprintf(buffer, "error %d\n", err);
441 		return;
442 	}
443 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
444 	snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
445 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
446 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
447 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
448 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
449 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
450 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
451 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
452 	snd_iprintf(buffer, "-----\n");
453 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
454 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
455 }
456 
457 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
458 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
459 				    struct snd_info_buffer *buffer)
460 {
461 	struct snd_pcm_str *pstr = entry->private_data;
462 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
463 }
464 
465 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
466 				     struct snd_info_buffer *buffer)
467 {
468 	struct snd_pcm_str *pstr = entry->private_data;
469 	char line[64];
470 	if (!snd_info_get_line(buffer, line, sizeof(line)))
471 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
472 }
473 #endif
474 
475 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
476 {
477 	struct snd_pcm *pcm = pstr->pcm;
478 	struct snd_info_entry *entry;
479 	char name[16];
480 
481 	sprintf(name, "pcm%i%c", pcm->device,
482 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
483 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
484 		return -ENOMEM;
485 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
486 	if (snd_info_register(entry) < 0) {
487 		snd_info_free_entry(entry);
488 		return -ENOMEM;
489 	}
490 	pstr->proc_root = entry;
491 
492 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
493 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
494 		if (snd_info_register(entry) < 0) {
495 			snd_info_free_entry(entry);
496 			entry = NULL;
497 		}
498 	}
499 	pstr->proc_info_entry = entry;
500 
501 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
502 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
503 						pstr->proc_root)) != NULL) {
504 		entry->c.text.read = snd_pcm_xrun_debug_read;
505 		entry->c.text.write = snd_pcm_xrun_debug_write;
506 		entry->mode |= S_IWUSR;
507 		entry->private_data = pstr;
508 		if (snd_info_register(entry) < 0) {
509 			snd_info_free_entry(entry);
510 			entry = NULL;
511 		}
512 	}
513 	pstr->proc_xrun_debug_entry = entry;
514 #endif
515 	return 0;
516 }
517 
518 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
519 {
520 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
521 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
522 	pstr->proc_xrun_debug_entry = NULL;
523 #endif
524 	snd_info_free_entry(pstr->proc_info_entry);
525 	pstr->proc_info_entry = NULL;
526 	snd_info_free_entry(pstr->proc_root);
527 	pstr->proc_root = NULL;
528 	return 0;
529 }
530 
531 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
532 {
533 	struct snd_info_entry *entry;
534 	struct snd_card *card;
535 	char name[16];
536 
537 	card = substream->pcm->card;
538 
539 	sprintf(name, "sub%i", substream->number);
540 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
541 		return -ENOMEM;
542 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
543 	if (snd_info_register(entry) < 0) {
544 		snd_info_free_entry(entry);
545 		return -ENOMEM;
546 	}
547 	substream->proc_root = entry;
548 
549 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
550 		snd_info_set_text_ops(entry, substream,
551 				      snd_pcm_substream_proc_info_read);
552 		if (snd_info_register(entry) < 0) {
553 			snd_info_free_entry(entry);
554 			entry = NULL;
555 		}
556 	}
557 	substream->proc_info_entry = entry;
558 
559 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
560 		snd_info_set_text_ops(entry, substream,
561 				      snd_pcm_substream_proc_hw_params_read);
562 		if (snd_info_register(entry) < 0) {
563 			snd_info_free_entry(entry);
564 			entry = NULL;
565 		}
566 	}
567 	substream->proc_hw_params_entry = entry;
568 
569 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
570 		snd_info_set_text_ops(entry, substream,
571 				      snd_pcm_substream_proc_sw_params_read);
572 		if (snd_info_register(entry) < 0) {
573 			snd_info_free_entry(entry);
574 			entry = NULL;
575 		}
576 	}
577 	substream->proc_sw_params_entry = entry;
578 
579 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
580 		snd_info_set_text_ops(entry, substream,
581 				      snd_pcm_substream_proc_status_read);
582 		if (snd_info_register(entry) < 0) {
583 			snd_info_free_entry(entry);
584 			entry = NULL;
585 		}
586 	}
587 	substream->proc_status_entry = entry;
588 
589 	return 0;
590 }
591 
592 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
593 {
594 	snd_info_free_entry(substream->proc_info_entry);
595 	substream->proc_info_entry = NULL;
596 	snd_info_free_entry(substream->proc_hw_params_entry);
597 	substream->proc_hw_params_entry = NULL;
598 	snd_info_free_entry(substream->proc_sw_params_entry);
599 	substream->proc_sw_params_entry = NULL;
600 	snd_info_free_entry(substream->proc_status_entry);
601 	substream->proc_status_entry = NULL;
602 	snd_info_free_entry(substream->proc_root);
603 	substream->proc_root = NULL;
604 	return 0;
605 }
606 #else /* !CONFIG_SND_VERBOSE_PROCFS */
607 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
608 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
609 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
610 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
611 #endif /* CONFIG_SND_VERBOSE_PROCFS */
612 
613 /**
614  * snd_pcm_new_stream - create a new PCM stream
615  * @pcm: the pcm instance
616  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
617  * @substream_count: the number of substreams
618  *
619  * Creates a new stream for the pcm.
620  * The corresponding stream on the pcm must have been empty before
621  * calling this, i.e. zero must be given to the argument of
622  * snd_pcm_new().
623  *
624  * Returns zero if successful, or a negative error code on failure.
625  */
626 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
627 {
628 	int idx, err;
629 	struct snd_pcm_str *pstr = &pcm->streams[stream];
630 	struct snd_pcm_substream *substream, *prev;
631 
632 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
633 	mutex_init(&pstr->oss.setup_mutex);
634 #endif
635 	pstr->stream = stream;
636 	pstr->pcm = pcm;
637 	pstr->substream_count = substream_count;
638 	if (substream_count > 0) {
639 		err = snd_pcm_stream_proc_init(pstr);
640 		if (err < 0) {
641 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
642 			return err;
643 		}
644 	}
645 	prev = NULL;
646 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
647 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
648 		if (substream == NULL) {
649 			snd_printk(KERN_ERR "Cannot allocate PCM substream\n");
650 			return -ENOMEM;
651 		}
652 		substream->pcm = pcm;
653 		substream->pstr = pstr;
654 		substream->number = idx;
655 		substream->stream = stream;
656 		sprintf(substream->name, "subdevice #%i", idx);
657 		substream->buffer_bytes_max = UINT_MAX;
658 		if (prev == NULL)
659 			pstr->substream = substream;
660 		else
661 			prev->next = substream;
662 		err = snd_pcm_substream_proc_init(substream);
663 		if (err < 0) {
664 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
665 			if (prev == NULL)
666 				pstr->substream = NULL;
667 			else
668 				prev->next = NULL;
669 			kfree(substream);
670 			return err;
671 		}
672 		substream->group = &substream->self_group;
673 		spin_lock_init(&substream->self_group.lock);
674 		INIT_LIST_HEAD(&substream->self_group.substreams);
675 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
676 		atomic_set(&substream->mmap_count, 0);
677 		prev = substream;
678 	}
679 	return 0;
680 }
681 
682 EXPORT_SYMBOL(snd_pcm_new_stream);
683 
684 /**
685  * snd_pcm_new - create a new PCM instance
686  * @card: the card instance
687  * @id: the id string
688  * @device: the device index (zero based)
689  * @playback_count: the number of substreams for playback
690  * @capture_count: the number of substreams for capture
691  * @rpcm: the pointer to store the new pcm instance
692  *
693  * Creates a new PCM instance.
694  *
695  * The pcm operators have to be set afterwards to the new instance
696  * via snd_pcm_set_ops().
697  *
698  * Returns zero if successful, or a negative error code on failure.
699  */
700 int snd_pcm_new(struct snd_card *card, const char *id, int device,
701 		int playback_count, int capture_count,
702 	        struct snd_pcm ** rpcm)
703 {
704 	struct snd_pcm *pcm;
705 	int err;
706 	static struct snd_device_ops ops = {
707 		.dev_free = snd_pcm_dev_free,
708 		.dev_register =	snd_pcm_dev_register,
709 		.dev_disconnect = snd_pcm_dev_disconnect,
710 	};
711 
712 	if (snd_BUG_ON(!card))
713 		return -ENXIO;
714 	if (rpcm)
715 		*rpcm = NULL;
716 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
717 	if (pcm == NULL) {
718 		snd_printk(KERN_ERR "Cannot allocate PCM\n");
719 		return -ENOMEM;
720 	}
721 	pcm->card = card;
722 	pcm->device = device;
723 	if (id)
724 		strlcpy(pcm->id, id, sizeof(pcm->id));
725 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
726 		snd_pcm_free(pcm);
727 		return err;
728 	}
729 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
730 		snd_pcm_free(pcm);
731 		return err;
732 	}
733 	mutex_init(&pcm->open_mutex);
734 	init_waitqueue_head(&pcm->open_wait);
735 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
736 		snd_pcm_free(pcm);
737 		return err;
738 	}
739 	if (rpcm)
740 		*rpcm = pcm;
741 	return 0;
742 }
743 
744 EXPORT_SYMBOL(snd_pcm_new);
745 
746 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
747 {
748 	struct snd_pcm_substream *substream, *substream_next;
749 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
750 	struct snd_pcm_oss_setup *setup, *setupn;
751 #endif
752 	substream = pstr->substream;
753 	while (substream) {
754 		substream_next = substream->next;
755 		snd_pcm_timer_done(substream);
756 		snd_pcm_substream_proc_done(substream);
757 		kfree(substream);
758 		substream = substream_next;
759 	}
760 	snd_pcm_stream_proc_done(pstr);
761 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
762 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
763 		setupn = setup->next;
764 		kfree(setup->task_name);
765 		kfree(setup);
766 	}
767 #endif
768 }
769 
770 static int snd_pcm_free(struct snd_pcm *pcm)
771 {
772 	struct snd_pcm_notify *notify;
773 
774 	if (!pcm)
775 		return 0;
776 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
777 		notify->n_unregister(pcm);
778 	}
779 	if (pcm->private_free)
780 		pcm->private_free(pcm);
781 	snd_pcm_lib_preallocate_free_for_all(pcm);
782 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
783 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
784 	kfree(pcm);
785 	return 0;
786 }
787 
788 static int snd_pcm_dev_free(struct snd_device *device)
789 {
790 	struct snd_pcm *pcm = device->device_data;
791 	return snd_pcm_free(pcm);
792 }
793 
794 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
795 			     struct file *file,
796 			     struct snd_pcm_substream **rsubstream)
797 {
798 	struct snd_pcm_str * pstr;
799 	struct snd_pcm_substream *substream;
800 	struct snd_pcm_runtime *runtime;
801 	struct snd_ctl_file *kctl;
802 	struct snd_card *card;
803 	int prefer_subdevice = -1;
804 	size_t size;
805 
806 	if (snd_BUG_ON(!pcm || !rsubstream))
807 		return -ENXIO;
808 	*rsubstream = NULL;
809 	pstr = &pcm->streams[stream];
810 	if (pstr->substream == NULL || pstr->substream_count == 0)
811 		return -ENODEV;
812 
813 	card = pcm->card;
814 	read_lock(&card->ctl_files_rwlock);
815 	list_for_each_entry(kctl, &card->ctl_files, list) {
816 		if (kctl->pid == task_pid(current)) {
817 			prefer_subdevice = kctl->prefer_pcm_subdevice;
818 			if (prefer_subdevice != -1)
819 				break;
820 		}
821 	}
822 	read_unlock(&card->ctl_files_rwlock);
823 
824 	switch (stream) {
825 	case SNDRV_PCM_STREAM_PLAYBACK:
826 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
827 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
828 				if (SUBSTREAM_BUSY(substream))
829 					return -EAGAIN;
830 			}
831 		}
832 		break;
833 	case SNDRV_PCM_STREAM_CAPTURE:
834 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
835 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
836 				if (SUBSTREAM_BUSY(substream))
837 					return -EAGAIN;
838 			}
839 		}
840 		break;
841 	default:
842 		return -EINVAL;
843 	}
844 
845 	if (file->f_flags & O_APPEND) {
846 		if (prefer_subdevice < 0) {
847 			if (pstr->substream_count > 1)
848 				return -EINVAL; /* must be unique */
849 			substream = pstr->substream;
850 		} else {
851 			for (substream = pstr->substream; substream;
852 			     substream = substream->next)
853 				if (substream->number == prefer_subdevice)
854 					break;
855 		}
856 		if (! substream)
857 			return -ENODEV;
858 		if (! SUBSTREAM_BUSY(substream))
859 			return -EBADFD;
860 		substream->ref_count++;
861 		*rsubstream = substream;
862 		return 0;
863 	}
864 
865 	if (prefer_subdevice >= 0) {
866 		for (substream = pstr->substream; substream; substream = substream->next)
867 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
868 				goto __ok;
869 	}
870 	for (substream = pstr->substream; substream; substream = substream->next)
871 		if (!SUBSTREAM_BUSY(substream))
872 			break;
873       __ok:
874 	if (substream == NULL)
875 		return -EAGAIN;
876 
877 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
878 	if (runtime == NULL)
879 		return -ENOMEM;
880 
881 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
882 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
883 	if (runtime->status == NULL) {
884 		kfree(runtime);
885 		return -ENOMEM;
886 	}
887 	memset((void*)runtime->status, 0, size);
888 
889 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
890 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
891 	if (runtime->control == NULL) {
892 		snd_free_pages((void*)runtime->status,
893 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
894 		kfree(runtime);
895 		return -ENOMEM;
896 	}
897 	memset((void*)runtime->control, 0, size);
898 
899 	init_waitqueue_head(&runtime->sleep);
900 	init_waitqueue_head(&runtime->tsleep);
901 
902 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
903 
904 	substream->runtime = runtime;
905 	substream->private_data = pcm->private_data;
906 	substream->ref_count = 1;
907 	substream->f_flags = file->f_flags;
908 	substream->pid = get_pid(task_pid(current));
909 	pstr->substream_opened++;
910 	*rsubstream = substream;
911 	return 0;
912 }
913 
914 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
915 {
916 	struct snd_pcm_runtime *runtime;
917 
918 	if (PCM_RUNTIME_CHECK(substream))
919 		return;
920 	runtime = substream->runtime;
921 	if (runtime->private_free != NULL)
922 		runtime->private_free(runtime);
923 	snd_free_pages((void*)runtime->status,
924 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
925 	snd_free_pages((void*)runtime->control,
926 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
927 	kfree(runtime->hw_constraints.rules);
928 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
929 	if (runtime->hwptr_log)
930 		kfree(runtime->hwptr_log);
931 #endif
932 	kfree(runtime);
933 	substream->runtime = NULL;
934 	put_pid(substream->pid);
935 	substream->pid = NULL;
936 	substream->pstr->substream_opened--;
937 }
938 
939 static ssize_t show_pcm_class(struct device *dev,
940 			      struct device_attribute *attr, char *buf)
941 {
942 	struct snd_pcm *pcm;
943 	const char *str;
944 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
945 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
946 		[SNDRV_PCM_CLASS_MULTI] = "multi",
947 		[SNDRV_PCM_CLASS_MODEM] = "modem",
948 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
949 	};
950 
951 	if (! (pcm = dev_get_drvdata(dev)) ||
952 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
953 		str = "none";
954 	else
955 		str = strs[pcm->dev_class];
956         return snprintf(buf, PAGE_SIZE, "%s\n", str);
957 }
958 
959 static struct device_attribute pcm_attrs =
960 	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
961 
962 static int snd_pcm_dev_register(struct snd_device *device)
963 {
964 	int cidx, err;
965 	struct snd_pcm_substream *substream;
966 	struct snd_pcm_notify *notify;
967 	char str[16];
968 	struct snd_pcm *pcm;
969 	struct device *dev;
970 
971 	if (snd_BUG_ON(!device || !device->device_data))
972 		return -ENXIO;
973 	pcm = device->device_data;
974 	mutex_lock(&register_mutex);
975 	err = snd_pcm_add(pcm);
976 	if (err) {
977 		mutex_unlock(&register_mutex);
978 		return err;
979 	}
980 	for (cidx = 0; cidx < 2; cidx++) {
981 		int devtype = -1;
982 		if (pcm->streams[cidx].substream == NULL)
983 			continue;
984 		switch (cidx) {
985 		case SNDRV_PCM_STREAM_PLAYBACK:
986 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
987 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
988 			break;
989 		case SNDRV_PCM_STREAM_CAPTURE:
990 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
991 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
992 			break;
993 		}
994 		/* device pointer to use, pcm->dev takes precedence if
995 		 * it is assigned, otherwise fall back to card's device
996 		 * if possible */
997 		dev = pcm->dev;
998 		if (!dev)
999 			dev = snd_card_get_device_link(pcm->card);
1000 		/* register pcm */
1001 		err = snd_register_device_for_dev(devtype, pcm->card,
1002 						  pcm->device,
1003 						  &snd_pcm_f_ops[cidx],
1004 						  pcm, str, dev);
1005 		if (err < 0) {
1006 			list_del(&pcm->list);
1007 			mutex_unlock(&register_mutex);
1008 			return err;
1009 		}
1010 		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,
1011 					  &pcm_attrs);
1012 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1013 			snd_pcm_timer_init(substream);
1014 	}
1015 
1016 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1017 		notify->n_register(pcm);
1018 
1019 	mutex_unlock(&register_mutex);
1020 	return 0;
1021 }
1022 
1023 static int snd_pcm_dev_disconnect(struct snd_device *device)
1024 {
1025 	struct snd_pcm *pcm = device->device_data;
1026 	struct snd_pcm_notify *notify;
1027 	struct snd_pcm_substream *substream;
1028 	int cidx, devtype;
1029 
1030 	mutex_lock(&register_mutex);
1031 	if (list_empty(&pcm->list))
1032 		goto unlock;
1033 
1034 	list_del_init(&pcm->list);
1035 	for (cidx = 0; cidx < 2; cidx++)
1036 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1037 			if (substream->runtime)
1038 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1039 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1040 		notify->n_disconnect(pcm);
1041 	}
1042 	for (cidx = 0; cidx < 2; cidx++) {
1043 		devtype = -1;
1044 		switch (cidx) {
1045 		case SNDRV_PCM_STREAM_PLAYBACK:
1046 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1047 			break;
1048 		case SNDRV_PCM_STREAM_CAPTURE:
1049 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1050 			break;
1051 		}
1052 		snd_unregister_device(devtype, pcm->card, pcm->device);
1053 	}
1054  unlock:
1055 	mutex_unlock(&register_mutex);
1056 	return 0;
1057 }
1058 
1059 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1060 {
1061 	struct snd_pcm *pcm;
1062 
1063 	if (snd_BUG_ON(!notify ||
1064 		       !notify->n_register ||
1065 		       !notify->n_unregister ||
1066 		       !notify->n_disconnect))
1067 		return -EINVAL;
1068 	mutex_lock(&register_mutex);
1069 	if (nfree) {
1070 		list_del(&notify->list);
1071 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1072 			notify->n_unregister(pcm);
1073 	} else {
1074 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1075 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1076 			notify->n_register(pcm);
1077 	}
1078 	mutex_unlock(&register_mutex);
1079 	return 0;
1080 }
1081 
1082 EXPORT_SYMBOL(snd_pcm_notify);
1083 
1084 #ifdef CONFIG_PROC_FS
1085 /*
1086  *  Info interface
1087  */
1088 
1089 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1090 			      struct snd_info_buffer *buffer)
1091 {
1092 	struct snd_pcm *pcm;
1093 
1094 	mutex_lock(&register_mutex);
1095 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1096 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1097 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1098 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1099 			snd_iprintf(buffer, " : playback %i",
1100 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1101 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1102 			snd_iprintf(buffer, " : capture %i",
1103 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1104 		snd_iprintf(buffer, "\n");
1105 	}
1106 	mutex_unlock(&register_mutex);
1107 }
1108 
1109 static struct snd_info_entry *snd_pcm_proc_entry;
1110 
1111 static void snd_pcm_proc_init(void)
1112 {
1113 	struct snd_info_entry *entry;
1114 
1115 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1116 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1117 		if (snd_info_register(entry) < 0) {
1118 			snd_info_free_entry(entry);
1119 			entry = NULL;
1120 		}
1121 	}
1122 	snd_pcm_proc_entry = entry;
1123 }
1124 
1125 static void snd_pcm_proc_done(void)
1126 {
1127 	snd_info_free_entry(snd_pcm_proc_entry);
1128 }
1129 
1130 #else /* !CONFIG_PROC_FS */
1131 #define snd_pcm_proc_init()
1132 #define snd_pcm_proc_done()
1133 #endif /* CONFIG_PROC_FS */
1134 
1135 
1136 /*
1137  *  ENTRY functions
1138  */
1139 
1140 static int __init alsa_pcm_init(void)
1141 {
1142 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1143 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1144 	snd_pcm_proc_init();
1145 	return 0;
1146 }
1147 
1148 static void __exit alsa_pcm_exit(void)
1149 {
1150 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1151 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1152 	snd_pcm_proc_done();
1153 }
1154 
1155 module_init(alsa_pcm_init)
1156 module_exit(alsa_pcm_exit)
1157