xref: /openbmc/linux/sound/core/pcm.c (revision fd589a8f)
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 };
207 
208 const char *snd_pcm_format_name(snd_pcm_format_t format)
209 {
210 	return snd_pcm_format_names[format];
211 }
212 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
213 
214 #ifdef CONFIG_SND_VERBOSE_PROCFS
215 
216 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
217 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
218 #define READY(v) [SNDRV_PCM_READY_##v] = #v
219 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
220 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
221 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
222 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
223 #define START(v) [SNDRV_PCM_START_##v] = #v
224 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
225 
226 static char *snd_pcm_stream_names[] = {
227 	STREAM(PLAYBACK),
228 	STREAM(CAPTURE),
229 };
230 
231 static char *snd_pcm_state_names[] = {
232 	STATE(OPEN),
233 	STATE(SETUP),
234 	STATE(PREPARED),
235 	STATE(RUNNING),
236 	STATE(XRUN),
237 	STATE(DRAINING),
238 	STATE(PAUSED),
239 	STATE(SUSPENDED),
240 };
241 
242 static char *snd_pcm_access_names[] = {
243 	ACCESS(MMAP_INTERLEAVED),
244 	ACCESS(MMAP_NONINTERLEAVED),
245 	ACCESS(MMAP_COMPLEX),
246 	ACCESS(RW_INTERLEAVED),
247 	ACCESS(RW_NONINTERLEAVED),
248 };
249 
250 static char *snd_pcm_subformat_names[] = {
251 	SUBFORMAT(STD),
252 };
253 
254 static char *snd_pcm_tstamp_mode_names[] = {
255 	TSTAMP(NONE),
256 	TSTAMP(ENABLE),
257 };
258 
259 static const char *snd_pcm_stream_name(int stream)
260 {
261 	return snd_pcm_stream_names[stream];
262 }
263 
264 static const char *snd_pcm_access_name(snd_pcm_access_t access)
265 {
266 	return snd_pcm_access_names[access];
267 }
268 
269 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
270 {
271 	return snd_pcm_subformat_names[subformat];
272 }
273 
274 static const char *snd_pcm_tstamp_mode_name(int mode)
275 {
276 	return snd_pcm_tstamp_mode_names[mode];
277 }
278 
279 static const char *snd_pcm_state_name(snd_pcm_state_t state)
280 {
281 	return snd_pcm_state_names[state];
282 }
283 
284 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
285 #include <linux/soundcard.h>
286 
287 static const char *snd_pcm_oss_format_name(int format)
288 {
289 	switch (format) {
290 	case AFMT_MU_LAW:
291 		return "MU_LAW";
292 	case AFMT_A_LAW:
293 		return "A_LAW";
294 	case AFMT_IMA_ADPCM:
295 		return "IMA_ADPCM";
296 	case AFMT_U8:
297 		return "U8";
298 	case AFMT_S16_LE:
299 		return "S16_LE";
300 	case AFMT_S16_BE:
301 		return "S16_BE";
302 	case AFMT_S8:
303 		return "S8";
304 	case AFMT_U16_LE:
305 		return "U16_LE";
306 	case AFMT_U16_BE:
307 		return "U16_BE";
308 	case AFMT_MPEG:
309 		return "MPEG";
310 	default:
311 		return "unknown";
312 	}
313 }
314 #endif
315 
316 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
317 				   struct snd_info_buffer *buffer)
318 {
319 	struct snd_pcm_info *info;
320 	int err;
321 
322 	if (! substream)
323 		return;
324 
325 	info = kmalloc(sizeof(*info), GFP_KERNEL);
326 	if (! info) {
327 		printk(KERN_DEBUG "snd_pcm_proc_info_read: cannot malloc\n");
328 		return;
329 	}
330 
331 	err = snd_pcm_info(substream, info);
332 	if (err < 0) {
333 		snd_iprintf(buffer, "error %d\n", err);
334 		kfree(info);
335 		return;
336 	}
337 	snd_iprintf(buffer, "card: %d\n", info->card);
338 	snd_iprintf(buffer, "device: %d\n", info->device);
339 	snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
340 	snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
341 	snd_iprintf(buffer, "id: %s\n", info->id);
342 	snd_iprintf(buffer, "name: %s\n", info->name);
343 	snd_iprintf(buffer, "subname: %s\n", info->subname);
344 	snd_iprintf(buffer, "class: %d\n", info->dev_class);
345 	snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
346 	snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
347 	snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
348 	kfree(info);
349 }
350 
351 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
352 					  struct snd_info_buffer *buffer)
353 {
354 	snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
355 			       buffer);
356 }
357 
358 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
359 					     struct snd_info_buffer *buffer)
360 {
361 	snd_pcm_proc_info_read((struct snd_pcm_substream *)entry->private_data,
362 			       buffer);
363 }
364 
365 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
366 						  struct snd_info_buffer *buffer)
367 {
368 	struct snd_pcm_substream *substream = entry->private_data;
369 	struct snd_pcm_runtime *runtime = substream->runtime;
370 	if (!runtime) {
371 		snd_iprintf(buffer, "closed\n");
372 		return;
373 	}
374 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
375 		snd_iprintf(buffer, "no setup\n");
376 		return;
377 	}
378 	snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
379 	snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
380 	snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
381 	snd_iprintf(buffer, "channels: %u\n", runtime->channels);
382 	snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
383 	snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
384 	snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
385 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
386 	if (substream->oss.oss) {
387 		snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
388 		snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
389 		snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
390 		snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
391 		snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
392 		snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
393 	}
394 #endif
395 }
396 
397 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
398 						  struct snd_info_buffer *buffer)
399 {
400 	struct snd_pcm_substream *substream = entry->private_data;
401 	struct snd_pcm_runtime *runtime = substream->runtime;
402 	if (!runtime) {
403 		snd_iprintf(buffer, "closed\n");
404 		return;
405 	}
406 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
407 		snd_iprintf(buffer, "no setup\n");
408 		return;
409 	}
410 	snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
411 	snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
412 	snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
413 	snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
414 	snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
415 	snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
416 	snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
417 	snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
418 }
419 
420 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
421 					       struct snd_info_buffer *buffer)
422 {
423 	struct snd_pcm_substream *substream = entry->private_data;
424 	struct snd_pcm_runtime *runtime = substream->runtime;
425 	struct snd_pcm_status status;
426 	int err;
427 	if (!runtime) {
428 		snd_iprintf(buffer, "closed\n");
429 		return;
430 	}
431 	memset(&status, 0, sizeof(status));
432 	err = snd_pcm_status(substream, &status);
433 	if (err < 0) {
434 		snd_iprintf(buffer, "error %d\n", err);
435 		return;
436 	}
437 	snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
438 	snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
439 		status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
440 	snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
441 		status.tstamp.tv_sec, status.tstamp.tv_nsec);
442 	snd_iprintf(buffer, "delay       : %ld\n", status.delay);
443 	snd_iprintf(buffer, "avail       : %ld\n", status.avail);
444 	snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
445 	snd_iprintf(buffer, "-----\n");
446 	snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
447 	snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
448 }
449 
450 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
451 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
452 				    struct snd_info_buffer *buffer)
453 {
454 	struct snd_pcm_str *pstr = entry->private_data;
455 	snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
456 }
457 
458 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
459 				     struct snd_info_buffer *buffer)
460 {
461 	struct snd_pcm_str *pstr = entry->private_data;
462 	char line[64];
463 	if (!snd_info_get_line(buffer, line, sizeof(line)))
464 		pstr->xrun_debug = simple_strtoul(line, NULL, 10);
465 }
466 #endif
467 
468 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
469 {
470 	struct snd_pcm *pcm = pstr->pcm;
471 	struct snd_info_entry *entry;
472 	char name[16];
473 
474 	sprintf(name, "pcm%i%c", pcm->device,
475 		pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
476 	if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
477 		return -ENOMEM;
478 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
479 	if (snd_info_register(entry) < 0) {
480 		snd_info_free_entry(entry);
481 		return -ENOMEM;
482 	}
483 	pstr->proc_root = entry;
484 
485 	if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
486 		snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
487 		if (snd_info_register(entry) < 0) {
488 			snd_info_free_entry(entry);
489 			entry = NULL;
490 		}
491 	}
492 	pstr->proc_info_entry = entry;
493 
494 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
495 	if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
496 						pstr->proc_root)) != NULL) {
497 		entry->c.text.read = snd_pcm_xrun_debug_read;
498 		entry->c.text.write = snd_pcm_xrun_debug_write;
499 		entry->mode |= S_IWUSR;
500 		entry->private_data = pstr;
501 		if (snd_info_register(entry) < 0) {
502 			snd_info_free_entry(entry);
503 			entry = NULL;
504 		}
505 	}
506 	pstr->proc_xrun_debug_entry = entry;
507 #endif
508 	return 0;
509 }
510 
511 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
512 {
513 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
514 	snd_info_free_entry(pstr->proc_xrun_debug_entry);
515 	pstr->proc_xrun_debug_entry = NULL;
516 #endif
517 	snd_info_free_entry(pstr->proc_info_entry);
518 	pstr->proc_info_entry = NULL;
519 	snd_info_free_entry(pstr->proc_root);
520 	pstr->proc_root = NULL;
521 	return 0;
522 }
523 
524 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
525 {
526 	struct snd_info_entry *entry;
527 	struct snd_card *card;
528 	char name[16];
529 
530 	card = substream->pcm->card;
531 
532 	sprintf(name, "sub%i", substream->number);
533 	if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
534 		return -ENOMEM;
535 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
536 	if (snd_info_register(entry) < 0) {
537 		snd_info_free_entry(entry);
538 		return -ENOMEM;
539 	}
540 	substream->proc_root = entry;
541 
542 	if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
543 		snd_info_set_text_ops(entry, substream,
544 				      snd_pcm_substream_proc_info_read);
545 		if (snd_info_register(entry) < 0) {
546 			snd_info_free_entry(entry);
547 			entry = NULL;
548 		}
549 	}
550 	substream->proc_info_entry = entry;
551 
552 	if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
553 		snd_info_set_text_ops(entry, substream,
554 				      snd_pcm_substream_proc_hw_params_read);
555 		if (snd_info_register(entry) < 0) {
556 			snd_info_free_entry(entry);
557 			entry = NULL;
558 		}
559 	}
560 	substream->proc_hw_params_entry = entry;
561 
562 	if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
563 		snd_info_set_text_ops(entry, substream,
564 				      snd_pcm_substream_proc_sw_params_read);
565 		if (snd_info_register(entry) < 0) {
566 			snd_info_free_entry(entry);
567 			entry = NULL;
568 		}
569 	}
570 	substream->proc_sw_params_entry = entry;
571 
572 	if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
573 		snd_info_set_text_ops(entry, substream,
574 				      snd_pcm_substream_proc_status_read);
575 		if (snd_info_register(entry) < 0) {
576 			snd_info_free_entry(entry);
577 			entry = NULL;
578 		}
579 	}
580 	substream->proc_status_entry = entry;
581 
582 	return 0;
583 }
584 
585 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
586 {
587 	snd_info_free_entry(substream->proc_info_entry);
588 	substream->proc_info_entry = NULL;
589 	snd_info_free_entry(substream->proc_hw_params_entry);
590 	substream->proc_hw_params_entry = NULL;
591 	snd_info_free_entry(substream->proc_sw_params_entry);
592 	substream->proc_sw_params_entry = NULL;
593 	snd_info_free_entry(substream->proc_status_entry);
594 	substream->proc_status_entry = NULL;
595 	snd_info_free_entry(substream->proc_root);
596 	substream->proc_root = NULL;
597 	return 0;
598 }
599 #else /* !CONFIG_SND_VERBOSE_PROCFS */
600 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
601 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
602 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
603 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
604 #endif /* CONFIG_SND_VERBOSE_PROCFS */
605 
606 /**
607  * snd_pcm_new_stream - create a new PCM stream
608  * @pcm: the pcm instance
609  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
610  * @substream_count: the number of substreams
611  *
612  * Creates a new stream for the pcm.
613  * The corresponding stream on the pcm must have been empty before
614  * calling this, i.e. zero must be given to the argument of
615  * snd_pcm_new().
616  *
617  * Returns zero if successful, or a negative error code on failure.
618  */
619 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
620 {
621 	int idx, err;
622 	struct snd_pcm_str *pstr = &pcm->streams[stream];
623 	struct snd_pcm_substream *substream, *prev;
624 
625 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
626 	mutex_init(&pstr->oss.setup_mutex);
627 #endif
628 	pstr->stream = stream;
629 	pstr->pcm = pcm;
630 	pstr->substream_count = substream_count;
631 	if (substream_count > 0) {
632 		err = snd_pcm_stream_proc_init(pstr);
633 		if (err < 0) {
634 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
635 			return err;
636 		}
637 	}
638 	prev = NULL;
639 	for (idx = 0, prev = NULL; idx < substream_count; idx++) {
640 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
641 		if (substream == NULL) {
642 			snd_printk(KERN_ERR "Cannot allocate PCM substream\n");
643 			return -ENOMEM;
644 		}
645 		substream->pcm = pcm;
646 		substream->pstr = pstr;
647 		substream->number = idx;
648 		substream->stream = stream;
649 		sprintf(substream->name, "subdevice #%i", idx);
650 		snprintf(substream->latency_id, sizeof(substream->latency_id),
651 			 "ALSA-PCM%d-%d%c%d", pcm->card->number, pcm->device,
652 			 (stream ? 'c' : 'p'), idx);
653 		substream->buffer_bytes_max = UINT_MAX;
654 		if (prev == NULL)
655 			pstr->substream = substream;
656 		else
657 			prev->next = substream;
658 		err = snd_pcm_substream_proc_init(substream);
659 		if (err < 0) {
660 			snd_printk(KERN_ERR "Error in snd_pcm_stream_proc_init\n");
661 			if (prev == NULL)
662 				pstr->substream = NULL;
663 			else
664 				prev->next = NULL;
665 			kfree(substream);
666 			return err;
667 		}
668 		substream->group = &substream->self_group;
669 		spin_lock_init(&substream->self_group.lock);
670 		INIT_LIST_HEAD(&substream->self_group.substreams);
671 		list_add_tail(&substream->link_list, &substream->self_group.substreams);
672 		atomic_set(&substream->mmap_count, 0);
673 		prev = substream;
674 	}
675 	return 0;
676 }
677 
678 EXPORT_SYMBOL(snd_pcm_new_stream);
679 
680 /**
681  * snd_pcm_new - create a new PCM instance
682  * @card: the card instance
683  * @id: the id string
684  * @device: the device index (zero based)
685  * @playback_count: the number of substreams for playback
686  * @capture_count: the number of substreams for capture
687  * @rpcm: the pointer to store the new pcm instance
688  *
689  * Creates a new PCM instance.
690  *
691  * The pcm operators have to be set afterwards to the new instance
692  * via snd_pcm_set_ops().
693  *
694  * Returns zero if successful, or a negative error code on failure.
695  */
696 int snd_pcm_new(struct snd_card *card, const char *id, int device,
697 		int playback_count, int capture_count,
698 	        struct snd_pcm ** rpcm)
699 {
700 	struct snd_pcm *pcm;
701 	int err;
702 	static struct snd_device_ops ops = {
703 		.dev_free = snd_pcm_dev_free,
704 		.dev_register =	snd_pcm_dev_register,
705 		.dev_disconnect = snd_pcm_dev_disconnect,
706 	};
707 
708 	if (snd_BUG_ON(!card))
709 		return -ENXIO;
710 	if (rpcm)
711 		*rpcm = NULL;
712 	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
713 	if (pcm == NULL) {
714 		snd_printk(KERN_ERR "Cannot allocate PCM\n");
715 		return -ENOMEM;
716 	}
717 	pcm->card = card;
718 	pcm->device = device;
719 	if (id)
720 		strlcpy(pcm->id, id, sizeof(pcm->id));
721 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
722 		snd_pcm_free(pcm);
723 		return err;
724 	}
725 	if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
726 		snd_pcm_free(pcm);
727 		return err;
728 	}
729 	mutex_init(&pcm->open_mutex);
730 	init_waitqueue_head(&pcm->open_wait);
731 	if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
732 		snd_pcm_free(pcm);
733 		return err;
734 	}
735 	if (rpcm)
736 		*rpcm = pcm;
737 	return 0;
738 }
739 
740 EXPORT_SYMBOL(snd_pcm_new);
741 
742 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
743 {
744 	struct snd_pcm_substream *substream, *substream_next;
745 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
746 	struct snd_pcm_oss_setup *setup, *setupn;
747 #endif
748 	substream = pstr->substream;
749 	while (substream) {
750 		substream_next = substream->next;
751 		snd_pcm_timer_done(substream);
752 		snd_pcm_substream_proc_done(substream);
753 		kfree(substream);
754 		substream = substream_next;
755 	}
756 	snd_pcm_stream_proc_done(pstr);
757 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
758 	for (setup = pstr->oss.setup_list; setup; setup = setupn) {
759 		setupn = setup->next;
760 		kfree(setup->task_name);
761 		kfree(setup);
762 	}
763 #endif
764 }
765 
766 static int snd_pcm_free(struct snd_pcm *pcm)
767 {
768 	struct snd_pcm_notify *notify;
769 
770 	if (!pcm)
771 		return 0;
772 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
773 		notify->n_unregister(pcm);
774 	}
775 	if (pcm->private_free)
776 		pcm->private_free(pcm);
777 	snd_pcm_lib_preallocate_free_for_all(pcm);
778 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
779 	snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
780 	kfree(pcm);
781 	return 0;
782 }
783 
784 static int snd_pcm_dev_free(struct snd_device *device)
785 {
786 	struct snd_pcm *pcm = device->device_data;
787 	return snd_pcm_free(pcm);
788 }
789 
790 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
791 			     struct file *file,
792 			     struct snd_pcm_substream **rsubstream)
793 {
794 	struct snd_pcm_str * pstr;
795 	struct snd_pcm_substream *substream;
796 	struct snd_pcm_runtime *runtime;
797 	struct snd_ctl_file *kctl;
798 	struct snd_card *card;
799 	int prefer_subdevice = -1;
800 	size_t size;
801 
802 	if (snd_BUG_ON(!pcm || !rsubstream))
803 		return -ENXIO;
804 	*rsubstream = NULL;
805 	pstr = &pcm->streams[stream];
806 	if (pstr->substream == NULL || pstr->substream_count == 0)
807 		return -ENODEV;
808 
809 	card = pcm->card;
810 	read_lock(&card->ctl_files_rwlock);
811 	list_for_each_entry(kctl, &card->ctl_files, list) {
812 		if (kctl->pid == current->pid) {
813 			prefer_subdevice = kctl->prefer_pcm_subdevice;
814 			if (prefer_subdevice != -1)
815 				break;
816 		}
817 	}
818 	read_unlock(&card->ctl_files_rwlock);
819 
820 	switch (stream) {
821 	case SNDRV_PCM_STREAM_PLAYBACK:
822 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
823 			for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
824 				if (SUBSTREAM_BUSY(substream))
825 					return -EAGAIN;
826 			}
827 		}
828 		break;
829 	case SNDRV_PCM_STREAM_CAPTURE:
830 		if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
831 			for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
832 				if (SUBSTREAM_BUSY(substream))
833 					return -EAGAIN;
834 			}
835 		}
836 		break;
837 	default:
838 		return -EINVAL;
839 	}
840 
841 	if (file->f_flags & O_APPEND) {
842 		if (prefer_subdevice < 0) {
843 			if (pstr->substream_count > 1)
844 				return -EINVAL; /* must be unique */
845 			substream = pstr->substream;
846 		} else {
847 			for (substream = pstr->substream; substream;
848 			     substream = substream->next)
849 				if (substream->number == prefer_subdevice)
850 					break;
851 		}
852 		if (! substream)
853 			return -ENODEV;
854 		if (! SUBSTREAM_BUSY(substream))
855 			return -EBADFD;
856 		substream->ref_count++;
857 		*rsubstream = substream;
858 		return 0;
859 	}
860 
861 	if (prefer_subdevice >= 0) {
862 		for (substream = pstr->substream; substream; substream = substream->next)
863 			if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
864 				goto __ok;
865 	}
866 	for (substream = pstr->substream; substream; substream = substream->next)
867 		if (!SUBSTREAM_BUSY(substream))
868 			break;
869       __ok:
870 	if (substream == NULL)
871 		return -EAGAIN;
872 
873 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
874 	if (runtime == NULL)
875 		return -ENOMEM;
876 
877 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
878 	runtime->status = snd_malloc_pages(size, GFP_KERNEL);
879 	if (runtime->status == NULL) {
880 		kfree(runtime);
881 		return -ENOMEM;
882 	}
883 	memset((void*)runtime->status, 0, size);
884 
885 	size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
886 	runtime->control = snd_malloc_pages(size, GFP_KERNEL);
887 	if (runtime->control == NULL) {
888 		snd_free_pages((void*)runtime->status,
889 			       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
890 		kfree(runtime);
891 		return -ENOMEM;
892 	}
893 	memset((void*)runtime->control, 0, size);
894 
895 	init_waitqueue_head(&runtime->sleep);
896 
897 	runtime->status->state = SNDRV_PCM_STATE_OPEN;
898 
899 	substream->runtime = runtime;
900 	substream->private_data = pcm->private_data;
901 	substream->ref_count = 1;
902 	substream->f_flags = file->f_flags;
903 	pstr->substream_opened++;
904 	*rsubstream = substream;
905 	return 0;
906 }
907 
908 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
909 {
910 	struct snd_pcm_runtime *runtime;
911 
912 	if (PCM_RUNTIME_CHECK(substream))
913 		return;
914 	runtime = substream->runtime;
915 	if (runtime->private_free != NULL)
916 		runtime->private_free(runtime);
917 	snd_free_pages((void*)runtime->status,
918 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
919 	snd_free_pages((void*)runtime->control,
920 		       PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
921 	kfree(runtime->hw_constraints.rules);
922 	kfree(runtime);
923 	substream->runtime = NULL;
924 	substream->pstr->substream_opened--;
925 }
926 
927 static ssize_t show_pcm_class(struct device *dev,
928 			      struct device_attribute *attr, char *buf)
929 {
930 	struct snd_pcm *pcm;
931 	const char *str;
932 	static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
933 		[SNDRV_PCM_CLASS_GENERIC] = "generic",
934 		[SNDRV_PCM_CLASS_MULTI] = "multi",
935 		[SNDRV_PCM_CLASS_MODEM] = "modem",
936 		[SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
937 	};
938 
939 	if (! (pcm = dev_get_drvdata(dev)) ||
940 	    pcm->dev_class > SNDRV_PCM_CLASS_LAST)
941 		str = "none";
942 	else
943 		str = strs[pcm->dev_class];
944         return snprintf(buf, PAGE_SIZE, "%s\n", str);
945 }
946 
947 static struct device_attribute pcm_attrs =
948 	__ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
949 
950 static int snd_pcm_dev_register(struct snd_device *device)
951 {
952 	int cidx, err;
953 	struct snd_pcm_substream *substream;
954 	struct snd_pcm_notify *notify;
955 	char str[16];
956 	struct snd_pcm *pcm = device->device_data;
957 	struct device *dev;
958 
959 	if (snd_BUG_ON(!pcm || !device))
960 		return -ENXIO;
961 	mutex_lock(&register_mutex);
962 	err = snd_pcm_add(pcm);
963 	if (err) {
964 		mutex_unlock(&register_mutex);
965 		return err;
966 	}
967 	for (cidx = 0; cidx < 2; cidx++) {
968 		int devtype = -1;
969 		if (pcm->streams[cidx].substream == NULL)
970 			continue;
971 		switch (cidx) {
972 		case SNDRV_PCM_STREAM_PLAYBACK:
973 			sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
974 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
975 			break;
976 		case SNDRV_PCM_STREAM_CAPTURE:
977 			sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
978 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
979 			break;
980 		}
981 		/* device pointer to use, pcm->dev takes precedence if
982 		 * it is assigned, otherwise fall back to card's device
983 		 * if possible */
984 		dev = pcm->dev;
985 		if (!dev)
986 			dev = snd_card_get_device_link(pcm->card);
987 		/* register pcm */
988 		err = snd_register_device_for_dev(devtype, pcm->card,
989 						  pcm->device,
990 						  &snd_pcm_f_ops[cidx],
991 						  pcm, str, dev);
992 		if (err < 0) {
993 			list_del(&pcm->list);
994 			mutex_unlock(&register_mutex);
995 			return err;
996 		}
997 		snd_add_device_sysfs_file(devtype, pcm->card, pcm->device,
998 					  &pcm_attrs);
999 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1000 			snd_pcm_timer_init(substream);
1001 	}
1002 
1003 	list_for_each_entry(notify, &snd_pcm_notify_list, list)
1004 		notify->n_register(pcm);
1005 
1006 	mutex_unlock(&register_mutex);
1007 	return 0;
1008 }
1009 
1010 static int snd_pcm_dev_disconnect(struct snd_device *device)
1011 {
1012 	struct snd_pcm *pcm = device->device_data;
1013 	struct snd_pcm_notify *notify;
1014 	struct snd_pcm_substream *substream;
1015 	int cidx, devtype;
1016 
1017 	mutex_lock(&register_mutex);
1018 	if (list_empty(&pcm->list))
1019 		goto unlock;
1020 
1021 	list_del_init(&pcm->list);
1022 	for (cidx = 0; cidx < 2; cidx++)
1023 		for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1024 			if (substream->runtime)
1025 				substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1026 	list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1027 		notify->n_disconnect(pcm);
1028 	}
1029 	for (cidx = 0; cidx < 2; cidx++) {
1030 		devtype = -1;
1031 		switch (cidx) {
1032 		case SNDRV_PCM_STREAM_PLAYBACK:
1033 			devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1034 			break;
1035 		case SNDRV_PCM_STREAM_CAPTURE:
1036 			devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1037 			break;
1038 		}
1039 		snd_unregister_device(devtype, pcm->card, pcm->device);
1040 	}
1041  unlock:
1042 	mutex_unlock(&register_mutex);
1043 	return 0;
1044 }
1045 
1046 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1047 {
1048 	struct snd_pcm *pcm;
1049 
1050 	if (snd_BUG_ON(!notify ||
1051 		       !notify->n_register ||
1052 		       !notify->n_unregister ||
1053 		       !notify->n_disconnect))
1054 		return -EINVAL;
1055 	mutex_lock(&register_mutex);
1056 	if (nfree) {
1057 		list_del(&notify->list);
1058 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1059 			notify->n_unregister(pcm);
1060 	} else {
1061 		list_add_tail(&notify->list, &snd_pcm_notify_list);
1062 		list_for_each_entry(pcm, &snd_pcm_devices, list)
1063 			notify->n_register(pcm);
1064 	}
1065 	mutex_unlock(&register_mutex);
1066 	return 0;
1067 }
1068 
1069 EXPORT_SYMBOL(snd_pcm_notify);
1070 
1071 #ifdef CONFIG_PROC_FS
1072 /*
1073  *  Info interface
1074  */
1075 
1076 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1077 			      struct snd_info_buffer *buffer)
1078 {
1079 	struct snd_pcm *pcm;
1080 
1081 	mutex_lock(&register_mutex);
1082 	list_for_each_entry(pcm, &snd_pcm_devices, list) {
1083 		snd_iprintf(buffer, "%02i-%02i: %s : %s",
1084 			    pcm->card->number, pcm->device, pcm->id, pcm->name);
1085 		if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1086 			snd_iprintf(buffer, " : playback %i",
1087 				    pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1088 		if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1089 			snd_iprintf(buffer, " : capture %i",
1090 				    pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1091 		snd_iprintf(buffer, "\n");
1092 	}
1093 	mutex_unlock(&register_mutex);
1094 }
1095 
1096 static struct snd_info_entry *snd_pcm_proc_entry;
1097 
1098 static void snd_pcm_proc_init(void)
1099 {
1100 	struct snd_info_entry *entry;
1101 
1102 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1103 		snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1104 		if (snd_info_register(entry) < 0) {
1105 			snd_info_free_entry(entry);
1106 			entry = NULL;
1107 		}
1108 	}
1109 	snd_pcm_proc_entry = entry;
1110 }
1111 
1112 static void snd_pcm_proc_done(void)
1113 {
1114 	snd_info_free_entry(snd_pcm_proc_entry);
1115 }
1116 
1117 #else /* !CONFIG_PROC_FS */
1118 #define snd_pcm_proc_init()
1119 #define snd_pcm_proc_done()
1120 #endif /* CONFIG_PROC_FS */
1121 
1122 
1123 /*
1124  *  ENTRY functions
1125  */
1126 
1127 static int __init alsa_pcm_init(void)
1128 {
1129 	snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1130 	snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1131 	snd_pcm_proc_init();
1132 	return 0;
1133 }
1134 
1135 static void __exit alsa_pcm_exit(void)
1136 {
1137 	snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1138 	snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1139 	snd_pcm_proc_done();
1140 }
1141 
1142 module_init(alsa_pcm_init)
1143 module_exit(alsa_pcm_exit)
1144