2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
22 #include <linux/init.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/time.h>
26 #include <linux/mutex.h>
27 #include <linux/device.h>
28 #include <linux/nospec.h>
29 #include <sound/core.h>
30 #include <sound/minors.h>
31 #include <sound/pcm.h>
32 #include <sound/timer.h>
33 #include <sound/control.h>
34 #include <sound/info.h>
36 #include "pcm_local.h"
38 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
39 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
40 MODULE_LICENSE("GPL");
42 static LIST_HEAD(snd_pcm_devices);
43 static DEFINE_MUTEX(register_mutex);
44 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
45 static LIST_HEAD(snd_pcm_notify_list);
48 static int snd_pcm_free(struct snd_pcm *pcm);
49 static int snd_pcm_dev_free(struct snd_device *device);
50 static int snd_pcm_dev_register(struct snd_device *device);
51 static int snd_pcm_dev_disconnect(struct snd_device *device);
53 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
57 list_for_each_entry(pcm, &snd_pcm_devices, list) {
58 if (pcm->card == card && pcm->device == device)
64 static int snd_pcm_next(struct snd_card *card, int device)
68 list_for_each_entry(pcm, &snd_pcm_devices, list) {
69 if (pcm->card == card && pcm->device > device)
71 else if (pcm->card->number > card->number)
77 static int snd_pcm_add(struct snd_pcm *newpcm)
84 list_for_each_entry(pcm, &snd_pcm_devices, list) {
85 if (pcm->card == newpcm->card && pcm->device == newpcm->device)
87 if (pcm->card->number > newpcm->card->number ||
88 (pcm->card == newpcm->card &&
89 pcm->device > newpcm->device)) {
90 list_add(&newpcm->list, pcm->list.prev);
94 list_add_tail(&newpcm->list, &snd_pcm_devices);
98 static int snd_pcm_control_ioctl(struct snd_card *card,
99 struct snd_ctl_file *control,
100 unsigned int cmd, unsigned long arg)
103 case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
107 if (get_user(device, (int __user *)arg))
109 mutex_lock(®ister_mutex);
110 device = snd_pcm_next(card, device);
111 mutex_unlock(®ister_mutex);
112 if (put_user(device, (int __user *)arg))
116 case SNDRV_CTL_IOCTL_PCM_INFO:
118 struct snd_pcm_info __user *info;
119 unsigned int device, subdevice;
122 struct snd_pcm_str *pstr;
123 struct snd_pcm_substream *substream;
126 info = (struct snd_pcm_info __user *)arg;
127 if (get_user(device, &info->device))
129 if (get_user(stream, &info->stream))
131 if (stream < 0 || stream > 1)
133 stream = array_index_nospec(stream, 2);
134 if (get_user(subdevice, &info->subdevice))
136 mutex_lock(®ister_mutex);
137 pcm = snd_pcm_get(card, device);
142 pstr = &pcm->streams[stream];
143 if (pstr->substream_count == 0) {
147 if (subdevice >= pstr->substream_count) {
151 for (substream = pstr->substream; substream;
152 substream = substream->next)
153 if (substream->number == (int)subdevice)
155 if (substream == NULL) {
159 mutex_lock(&pcm->open_mutex);
160 err = snd_pcm_info_user(substream, info);
161 mutex_unlock(&pcm->open_mutex);
163 mutex_unlock(®ister_mutex);
166 case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
170 if (get_user(val, (int __user *)arg))
172 control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
179 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
181 static char *snd_pcm_format_names[] = {
200 FORMAT(IEC958_SUBFRAME_LE),
201 FORMAT(IEC958_SUBFRAME_BE),
232 * snd_pcm_format_name - Return a name string for the given PCM format
233 * @format: PCM format
235 const char *snd_pcm_format_name(snd_pcm_format_t format)
237 if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
239 return snd_pcm_format_names[(__force unsigned int)format];
241 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
243 #ifdef CONFIG_SND_VERBOSE_PROCFS
245 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
246 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
247 #define READY(v) [SNDRV_PCM_READY_##v] = #v
248 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
249 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
250 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
251 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
252 #define START(v) [SNDRV_PCM_START_##v] = #v
253 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
255 static char *snd_pcm_stream_names[] = {
260 static char *snd_pcm_state_names[] = {
272 static char *snd_pcm_access_names[] = {
273 ACCESS(MMAP_INTERLEAVED),
274 ACCESS(MMAP_NONINTERLEAVED),
275 ACCESS(MMAP_COMPLEX),
276 ACCESS(RW_INTERLEAVED),
277 ACCESS(RW_NONINTERLEAVED),
280 static char *snd_pcm_subformat_names[] = {
284 static char *snd_pcm_tstamp_mode_names[] = {
289 static const char *snd_pcm_stream_name(int stream)
291 return snd_pcm_stream_names[stream];
294 static const char *snd_pcm_access_name(snd_pcm_access_t access)
296 return snd_pcm_access_names[(__force int)access];
299 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
301 return snd_pcm_subformat_names[(__force int)subformat];
304 static const char *snd_pcm_tstamp_mode_name(int mode)
306 return snd_pcm_tstamp_mode_names[mode];
309 static const char *snd_pcm_state_name(snd_pcm_state_t state)
311 return snd_pcm_state_names[(__force int)state];
314 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
315 #include <linux/soundcard.h>
317 static const char *snd_pcm_oss_format_name(int format)
346 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
347 struct snd_info_buffer *buffer)
349 struct snd_pcm_info *info;
355 info = kmalloc(sizeof(*info), GFP_KERNEL);
359 err = snd_pcm_info(substream, info);
361 snd_iprintf(buffer, "error %d\n", err);
365 snd_iprintf(buffer, "card: %d\n", info->card);
366 snd_iprintf(buffer, "device: %d\n", info->device);
367 snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
368 snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
369 snd_iprintf(buffer, "id: %s\n", info->id);
370 snd_iprintf(buffer, "name: %s\n", info->name);
371 snd_iprintf(buffer, "subname: %s\n", info->subname);
372 snd_iprintf(buffer, "class: %d\n", info->dev_class);
373 snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
374 snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
375 snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
379 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
380 struct snd_info_buffer *buffer)
382 snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
386 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
387 struct snd_info_buffer *buffer)
389 snd_pcm_proc_info_read(entry->private_data, buffer);
392 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
393 struct snd_info_buffer *buffer)
395 struct snd_pcm_substream *substream = entry->private_data;
396 struct snd_pcm_runtime *runtime;
398 mutex_lock(&substream->pcm->open_mutex);
399 runtime = substream->runtime;
401 snd_iprintf(buffer, "closed\n");
404 if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
405 snd_iprintf(buffer, "no setup\n");
408 snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
409 snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
410 snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
411 snd_iprintf(buffer, "channels: %u\n", runtime->channels);
412 snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
413 snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
414 snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
415 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
416 if (substream->oss.oss) {
417 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
418 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
419 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
420 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
421 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
422 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
426 mutex_unlock(&substream->pcm->open_mutex);
429 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
430 struct snd_info_buffer *buffer)
432 struct snd_pcm_substream *substream = entry->private_data;
433 struct snd_pcm_runtime *runtime;
435 mutex_lock(&substream->pcm->open_mutex);
436 runtime = substream->runtime;
438 snd_iprintf(buffer, "closed\n");
441 if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
442 snd_iprintf(buffer, "no setup\n");
445 snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
446 snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
447 snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
448 snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
449 snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
450 snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
451 snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
452 snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
454 mutex_unlock(&substream->pcm->open_mutex);
457 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
458 struct snd_info_buffer *buffer)
460 struct snd_pcm_substream *substream = entry->private_data;
461 struct snd_pcm_runtime *runtime;
462 struct snd_pcm_status status;
465 mutex_lock(&substream->pcm->open_mutex);
466 runtime = substream->runtime;
468 snd_iprintf(buffer, "closed\n");
471 memset(&status, 0, sizeof(status));
472 err = snd_pcm_status(substream, &status);
474 snd_iprintf(buffer, "error %d\n", err);
477 snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
478 snd_iprintf(buffer, "owner_pid : %d\n", pid_vnr(substream->pid));
479 snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
480 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
481 snd_iprintf(buffer, "tstamp : %ld.%09ld\n",
482 status.tstamp.tv_sec, status.tstamp.tv_nsec);
483 snd_iprintf(buffer, "delay : %ld\n", status.delay);
484 snd_iprintf(buffer, "avail : %ld\n", status.avail);
485 snd_iprintf(buffer, "avail_max : %ld\n", status.avail_max);
486 snd_iprintf(buffer, "-----\n");
487 snd_iprintf(buffer, "hw_ptr : %ld\n", runtime->status->hw_ptr);
488 snd_iprintf(buffer, "appl_ptr : %ld\n", runtime->control->appl_ptr);
490 mutex_unlock(&substream->pcm->open_mutex);
493 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
494 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
495 struct snd_info_buffer *buffer)
497 struct snd_pcm_substream *substream = entry->private_data;
499 snd_pcm_stop_xrun(substream);
502 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
503 struct snd_info_buffer *buffer)
505 struct snd_pcm_str *pstr = entry->private_data;
506 snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
509 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
510 struct snd_info_buffer *buffer)
512 struct snd_pcm_str *pstr = entry->private_data;
514 if (!snd_info_get_line(buffer, line, sizeof(line)))
515 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
519 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
521 struct snd_pcm *pcm = pstr->pcm;
522 struct snd_info_entry *entry;
525 sprintf(name, "pcm%i%c", pcm->device,
526 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
527 entry = snd_info_create_card_entry(pcm->card, name,
528 pcm->card->proc_root);
531 entry->mode = S_IFDIR | 0555;
532 if (snd_info_register(entry) < 0) {
533 snd_info_free_entry(entry);
536 pstr->proc_root = entry;
537 entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
539 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
540 if (snd_info_register(entry) < 0) {
541 snd_info_free_entry(entry);
545 pstr->proc_info_entry = entry;
547 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
548 entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
551 entry->c.text.read = snd_pcm_xrun_debug_read;
552 entry->c.text.write = snd_pcm_xrun_debug_write;
554 entry->private_data = pstr;
555 if (snd_info_register(entry) < 0) {
556 snd_info_free_entry(entry);
560 pstr->proc_xrun_debug_entry = entry;
565 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
567 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
568 snd_info_free_entry(pstr->proc_xrun_debug_entry);
569 pstr->proc_xrun_debug_entry = NULL;
571 snd_info_free_entry(pstr->proc_info_entry);
572 pstr->proc_info_entry = NULL;
573 snd_info_free_entry(pstr->proc_root);
574 pstr->proc_root = NULL;
578 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
580 struct snd_info_entry *entry;
581 struct snd_card *card;
584 card = substream->pcm->card;
586 sprintf(name, "sub%i", substream->number);
587 entry = snd_info_create_card_entry(card, name,
588 substream->pstr->proc_root);
591 entry->mode = S_IFDIR | 0555;
592 if (snd_info_register(entry) < 0) {
593 snd_info_free_entry(entry);
596 substream->proc_root = entry;
597 entry = snd_info_create_card_entry(card, "info", substream->proc_root);
599 snd_info_set_text_ops(entry, substream,
600 snd_pcm_substream_proc_info_read);
601 if (snd_info_register(entry) < 0) {
602 snd_info_free_entry(entry);
606 substream->proc_info_entry = entry;
607 entry = snd_info_create_card_entry(card, "hw_params",
608 substream->proc_root);
610 snd_info_set_text_ops(entry, substream,
611 snd_pcm_substream_proc_hw_params_read);
612 if (snd_info_register(entry) < 0) {
613 snd_info_free_entry(entry);
617 substream->proc_hw_params_entry = entry;
618 entry = snd_info_create_card_entry(card, "sw_params",
619 substream->proc_root);
621 snd_info_set_text_ops(entry, substream,
622 snd_pcm_substream_proc_sw_params_read);
623 if (snd_info_register(entry) < 0) {
624 snd_info_free_entry(entry);
628 substream->proc_sw_params_entry = entry;
629 entry = snd_info_create_card_entry(card, "status",
630 substream->proc_root);
632 snd_info_set_text_ops(entry, substream,
633 snd_pcm_substream_proc_status_read);
634 if (snd_info_register(entry) < 0) {
635 snd_info_free_entry(entry);
639 substream->proc_status_entry = entry;
641 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
642 entry = snd_info_create_card_entry(card, "xrun_injection",
643 substream->proc_root);
645 entry->private_data = substream;
646 entry->c.text.read = NULL;
647 entry->c.text.write = snd_pcm_xrun_injection_write;
648 entry->mode = S_IFREG | 0200;
649 if (snd_info_register(entry) < 0) {
650 snd_info_free_entry(entry);
654 substream->proc_xrun_injection_entry = entry;
655 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
660 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
662 snd_info_free_entry(substream->proc_info_entry);
663 substream->proc_info_entry = NULL;
664 snd_info_free_entry(substream->proc_hw_params_entry);
665 substream->proc_hw_params_entry = NULL;
666 snd_info_free_entry(substream->proc_sw_params_entry);
667 substream->proc_sw_params_entry = NULL;
668 snd_info_free_entry(substream->proc_status_entry);
669 substream->proc_status_entry = NULL;
670 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
671 snd_info_free_entry(substream->proc_xrun_injection_entry);
672 substream->proc_xrun_injection_entry = NULL;
674 snd_info_free_entry(substream->proc_root);
675 substream->proc_root = NULL;
678 #else /* !CONFIG_SND_VERBOSE_PROCFS */
679 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
680 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
681 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
682 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
683 #endif /* CONFIG_SND_VERBOSE_PROCFS */
685 static const struct attribute_group *pcm_dev_attr_groups[];
688 * snd_pcm_new_stream - create a new PCM stream
689 * @pcm: the pcm instance
690 * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
691 * @substream_count: the number of substreams
693 * Creates a new stream for the pcm.
694 * The corresponding stream on the pcm must have been empty before
695 * calling this, i.e. zero must be given to the argument of
698 * Return: Zero if successful, or a negative error code on failure.
700 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
703 struct snd_pcm_str *pstr = &pcm->streams[stream];
704 struct snd_pcm_substream *substream, *prev;
706 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
707 mutex_init(&pstr->oss.setup_mutex);
709 pstr->stream = stream;
711 pstr->substream_count = substream_count;
712 if (!substream_count)
715 snd_device_initialize(&pstr->dev, pcm->card);
716 pstr->dev.groups = pcm_dev_attr_groups;
717 dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
718 stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
720 if (!pcm->internal) {
721 err = snd_pcm_stream_proc_init(pstr);
723 pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
728 for (idx = 0, prev = NULL; idx < substream_count; idx++) {
729 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
732 substream->pcm = pcm;
733 substream->pstr = pstr;
734 substream->number = idx;
735 substream->stream = stream;
736 sprintf(substream->name, "subdevice #%i", idx);
737 substream->buffer_bytes_max = UINT_MAX;
739 pstr->substream = substream;
741 prev->next = substream;
743 if (!pcm->internal) {
744 err = snd_pcm_substream_proc_init(substream);
747 "Error in snd_pcm_stream_proc_init\n");
749 pstr->substream = NULL;
756 substream->group = &substream->self_group;
757 spin_lock_init(&substream->self_group.lock);
758 mutex_init(&substream->self_group.mutex);
759 INIT_LIST_HEAD(&substream->self_group.substreams);
760 list_add_tail(&substream->link_list, &substream->self_group.substreams);
761 atomic_set(&substream->mmap_count, 0);
766 EXPORT_SYMBOL(snd_pcm_new_stream);
768 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
769 int playback_count, int capture_count, bool internal,
770 struct snd_pcm **rpcm)
774 static struct snd_device_ops ops = {
775 .dev_free = snd_pcm_dev_free,
776 .dev_register = snd_pcm_dev_register,
777 .dev_disconnect = snd_pcm_dev_disconnect,
779 static struct snd_device_ops internal_ops = {
780 .dev_free = snd_pcm_dev_free,
783 if (snd_BUG_ON(!card))
787 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
791 pcm->device = device;
792 pcm->internal = internal;
793 mutex_init(&pcm->open_mutex);
794 init_waitqueue_head(&pcm->open_wait);
795 INIT_LIST_HEAD(&pcm->list);
797 strlcpy(pcm->id, id, sizeof(pcm->id));
799 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
804 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
808 err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
809 internal ? &internal_ops : &ops);
823 * snd_pcm_new - create a new PCM instance
824 * @card: the card instance
826 * @device: the device index (zero based)
827 * @playback_count: the number of substreams for playback
828 * @capture_count: the number of substreams for capture
829 * @rpcm: the pointer to store the new pcm instance
831 * Creates a new PCM instance.
833 * The pcm operators have to be set afterwards to the new instance
834 * via snd_pcm_set_ops().
836 * Return: Zero if successful, or a negative error code on failure.
838 int snd_pcm_new(struct snd_card *card, const char *id, int device,
839 int playback_count, int capture_count, struct snd_pcm **rpcm)
841 return _snd_pcm_new(card, id, device, playback_count, capture_count,
844 EXPORT_SYMBOL(snd_pcm_new);
847 * snd_pcm_new_internal - create a new internal PCM instance
848 * @card: the card instance
850 * @device: the device index (zero based - shared with normal PCMs)
851 * @playback_count: the number of substreams for playback
852 * @capture_count: the number of substreams for capture
853 * @rpcm: the pointer to store the new pcm instance
855 * Creates a new internal PCM instance with no userspace device or procfs
856 * entries. This is used by ASoC Back End PCMs in order to create a PCM that
857 * will only be used internally by kernel drivers. i.e. it cannot be opened
858 * by userspace. It provides existing ASoC components drivers with a substream
859 * and access to any private data.
861 * The pcm operators have to be set afterwards to the new instance
862 * via snd_pcm_set_ops().
864 * Return: Zero if successful, or a negative error code on failure.
866 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
867 int playback_count, int capture_count,
868 struct snd_pcm **rpcm)
870 return _snd_pcm_new(card, id, device, playback_count, capture_count,
873 EXPORT_SYMBOL(snd_pcm_new_internal);
875 static void free_chmap(struct snd_pcm_str *pstr)
877 if (pstr->chmap_kctl) {
878 struct snd_card *card = pstr->pcm->card;
880 down_write(&card->controls_rwsem);
881 snd_ctl_remove(card, pstr->chmap_kctl);
882 up_write(&card->controls_rwsem);
883 pstr->chmap_kctl = NULL;
887 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
889 struct snd_pcm_substream *substream, *substream_next;
890 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
891 struct snd_pcm_oss_setup *setup, *setupn;
893 substream = pstr->substream;
895 substream_next = substream->next;
896 snd_pcm_timer_done(substream);
897 snd_pcm_substream_proc_done(substream);
899 substream = substream_next;
901 snd_pcm_stream_proc_done(pstr);
902 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
903 for (setup = pstr->oss.setup_list; setup; setup = setupn) {
904 setupn = setup->next;
905 kfree(setup->task_name);
910 if (pstr->substream_count)
911 put_device(&pstr->dev);
914 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
915 #define pcm_call_notify(pcm, call) \
917 struct snd_pcm_notify *_notify; \
918 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
919 _notify->call(pcm); \
922 #define pcm_call_notify(pcm, call) do {} while (0)
925 static int snd_pcm_free(struct snd_pcm *pcm)
930 pcm_call_notify(pcm, n_unregister);
931 if (pcm->private_free)
932 pcm->private_free(pcm);
933 snd_pcm_lib_preallocate_free_for_all(pcm);
934 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
935 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
940 static int snd_pcm_dev_free(struct snd_device *device)
942 struct snd_pcm *pcm = device->device_data;
943 return snd_pcm_free(pcm);
946 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
948 struct snd_pcm_substream **rsubstream)
950 struct snd_pcm_str * pstr;
951 struct snd_pcm_substream *substream;
952 struct snd_pcm_runtime *runtime;
953 struct snd_card *card;
954 int prefer_subdevice;
957 if (snd_BUG_ON(!pcm || !rsubstream))
959 if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
960 stream != SNDRV_PCM_STREAM_CAPTURE))
963 pstr = &pcm->streams[stream];
964 if (pstr->substream == NULL || pstr->substream_count == 0)
968 prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
970 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
971 int opposite = !stream;
973 for (substream = pcm->streams[opposite].substream; substream;
974 substream = substream->next) {
975 if (SUBSTREAM_BUSY(substream))
980 if (file->f_flags & O_APPEND) {
981 if (prefer_subdevice < 0) {
982 if (pstr->substream_count > 1)
983 return -EINVAL; /* must be unique */
984 substream = pstr->substream;
986 for (substream = pstr->substream; substream;
987 substream = substream->next)
988 if (substream->number == prefer_subdevice)
993 if (! SUBSTREAM_BUSY(substream))
995 substream->ref_count++;
996 *rsubstream = substream;
1000 for (substream = pstr->substream; substream; substream = substream->next) {
1001 if (!SUBSTREAM_BUSY(substream) &&
1002 (prefer_subdevice == -1 ||
1003 substream->number == prefer_subdevice))
1006 if (substream == NULL)
1009 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
1010 if (runtime == NULL)
1013 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
1014 runtime->status = snd_malloc_pages(size, GFP_KERNEL);
1015 if (runtime->status == NULL) {
1019 memset((void*)runtime->status, 0, size);
1021 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
1022 runtime->control = snd_malloc_pages(size, GFP_KERNEL);
1023 if (runtime->control == NULL) {
1024 snd_free_pages((void*)runtime->status,
1025 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1029 memset((void*)runtime->control, 0, size);
1031 init_waitqueue_head(&runtime->sleep);
1032 init_waitqueue_head(&runtime->tsleep);
1034 runtime->status->state = SNDRV_PCM_STATE_OPEN;
1035 mutex_init(&runtime->buffer_mutex);
1036 atomic_set(&runtime->buffer_accessing, 0);
1038 substream->runtime = runtime;
1039 substream->private_data = pcm->private_data;
1040 substream->ref_count = 1;
1041 substream->f_flags = file->f_flags;
1042 substream->pid = get_pid(task_pid(current));
1043 pstr->substream_opened++;
1044 *rsubstream = substream;
1048 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1050 struct snd_pcm_runtime *runtime;
1052 if (PCM_RUNTIME_CHECK(substream))
1054 runtime = substream->runtime;
1055 if (runtime->private_free != NULL)
1056 runtime->private_free(runtime);
1057 snd_free_pages((void*)runtime->status,
1058 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1059 snd_free_pages((void*)runtime->control,
1060 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1061 kfree(runtime->hw_constraints.rules);
1062 /* Avoid concurrent access to runtime via PCM timer interface */
1063 if (substream->timer)
1064 spin_lock_irq(&substream->timer->lock);
1065 substream->runtime = NULL;
1066 if (substream->timer)
1067 spin_unlock_irq(&substream->timer->lock);
1068 mutex_destroy(&runtime->buffer_mutex);
1070 put_pid(substream->pid);
1071 substream->pid = NULL;
1072 substream->pstr->substream_opened--;
1075 static ssize_t show_pcm_class(struct device *dev,
1076 struct device_attribute *attr, char *buf)
1078 struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
1079 struct snd_pcm *pcm = pstr->pcm;
1081 static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1082 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1083 [SNDRV_PCM_CLASS_MULTI] = "multi",
1084 [SNDRV_PCM_CLASS_MODEM] = "modem",
1085 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1088 if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1091 str = strs[pcm->dev_class];
1092 return snprintf(buf, PAGE_SIZE, "%s\n", str);
1095 static DEVICE_ATTR(pcm_class, 0444, show_pcm_class, NULL);
1096 static struct attribute *pcm_dev_attrs[] = {
1097 &dev_attr_pcm_class.attr,
1101 static const struct attribute_group pcm_dev_attr_group = {
1102 .attrs = pcm_dev_attrs,
1105 static const struct attribute_group *pcm_dev_attr_groups[] = {
1106 &pcm_dev_attr_group,
1110 static int snd_pcm_dev_register(struct snd_device *device)
1113 struct snd_pcm_substream *substream;
1114 struct snd_pcm *pcm;
1116 if (snd_BUG_ON(!device || !device->device_data))
1118 pcm = device->device_data;
1120 mutex_lock(®ister_mutex);
1121 err = snd_pcm_add(pcm);
1124 for (cidx = 0; cidx < 2; cidx++) {
1126 if (pcm->streams[cidx].substream == NULL)
1129 case SNDRV_PCM_STREAM_PLAYBACK:
1130 devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1132 case SNDRV_PCM_STREAM_CAPTURE:
1133 devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1137 err = snd_register_device(devtype, pcm->card, pcm->device,
1138 &snd_pcm_f_ops[cidx], pcm,
1139 &pcm->streams[cidx].dev);
1141 list_del_init(&pcm->list);
1145 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1146 snd_pcm_timer_init(substream);
1149 pcm_call_notify(pcm, n_register);
1152 mutex_unlock(®ister_mutex);
1156 static int snd_pcm_dev_disconnect(struct snd_device *device)
1158 struct snd_pcm *pcm = device->device_data;
1159 struct snd_pcm_substream *substream;
1162 mutex_lock(®ister_mutex);
1163 mutex_lock(&pcm->open_mutex);
1164 wake_up(&pcm->open_wait);
1165 list_del_init(&pcm->list);
1166 for (cidx = 0; cidx < 2; cidx++) {
1167 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1168 snd_pcm_stream_lock_irq(substream);
1169 if (substream->runtime) {
1170 if (snd_pcm_running(substream))
1171 snd_pcm_stop(substream,
1172 SNDRV_PCM_STATE_DISCONNECTED);
1173 /* to be sure, set the state unconditionally */
1174 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1175 wake_up(&substream->runtime->sleep);
1176 wake_up(&substream->runtime->tsleep);
1178 snd_pcm_stream_unlock_irq(substream);
1182 pcm_call_notify(pcm, n_disconnect);
1183 for (cidx = 0; cidx < 2; cidx++) {
1184 snd_unregister_device(&pcm->streams[cidx].dev);
1185 free_chmap(&pcm->streams[cidx]);
1187 mutex_unlock(&pcm->open_mutex);
1188 mutex_unlock(®ister_mutex);
1192 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1194 * snd_pcm_notify - Add/remove the notify list
1195 * @notify: PCM notify list
1196 * @nfree: 0 = register, 1 = unregister
1198 * This adds the given notifier to the global list so that the callback is
1199 * called for each registered PCM devices. This exists only for PCM OSS
1200 * emulation, so far.
1202 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1204 struct snd_pcm *pcm;
1206 if (snd_BUG_ON(!notify ||
1207 !notify->n_register ||
1208 !notify->n_unregister ||
1209 !notify->n_disconnect))
1211 mutex_lock(®ister_mutex);
1213 list_del(¬ify->list);
1214 list_for_each_entry(pcm, &snd_pcm_devices, list)
1215 notify->n_unregister(pcm);
1217 list_add_tail(¬ify->list, &snd_pcm_notify_list);
1218 list_for_each_entry(pcm, &snd_pcm_devices, list)
1219 notify->n_register(pcm);
1221 mutex_unlock(®ister_mutex);
1224 EXPORT_SYMBOL(snd_pcm_notify);
1225 #endif /* CONFIG_SND_PCM_OSS */
1227 #ifdef CONFIG_SND_PROC_FS
1232 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1233 struct snd_info_buffer *buffer)
1235 struct snd_pcm *pcm;
1237 mutex_lock(®ister_mutex);
1238 list_for_each_entry(pcm, &snd_pcm_devices, list) {
1239 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1240 pcm->card->number, pcm->device, pcm->id, pcm->name);
1241 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1242 snd_iprintf(buffer, " : playback %i",
1243 pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1244 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1245 snd_iprintf(buffer, " : capture %i",
1246 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1247 snd_iprintf(buffer, "\n");
1249 mutex_unlock(®ister_mutex);
1252 static struct snd_info_entry *snd_pcm_proc_entry;
1254 static void snd_pcm_proc_init(void)
1256 struct snd_info_entry *entry;
1258 entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1260 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1261 if (snd_info_register(entry) < 0) {
1262 snd_info_free_entry(entry);
1266 snd_pcm_proc_entry = entry;
1269 static void snd_pcm_proc_done(void)
1271 snd_info_free_entry(snd_pcm_proc_entry);
1274 #else /* !CONFIG_SND_PROC_FS */
1275 #define snd_pcm_proc_init()
1276 #define snd_pcm_proc_done()
1277 #endif /* CONFIG_SND_PROC_FS */
1284 static int __init alsa_pcm_init(void)
1286 snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1287 snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1288 snd_pcm_proc_init();
1292 static void __exit alsa_pcm_exit(void)
1294 snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1295 snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1296 snd_pcm_proc_done();
1299 module_init(alsa_pcm_init)
1300 module_exit(alsa_pcm_exit)