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[] = {
271 static char *snd_pcm_access_names[] = {
272 ACCESS(MMAP_INTERLEAVED),
273 ACCESS(MMAP_NONINTERLEAVED),
274 ACCESS(MMAP_COMPLEX),
275 ACCESS(RW_INTERLEAVED),
276 ACCESS(RW_NONINTERLEAVED),
279 static char *snd_pcm_subformat_names[] = {
283 static char *snd_pcm_tstamp_mode_names[] = {
288 static const char *snd_pcm_stream_name(int stream)
290 return snd_pcm_stream_names[stream];
293 static const char *snd_pcm_access_name(snd_pcm_access_t access)
295 return snd_pcm_access_names[(__force int)access];
298 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
300 return snd_pcm_subformat_names[(__force int)subformat];
303 static const char *snd_pcm_tstamp_mode_name(int mode)
305 return snd_pcm_tstamp_mode_names[mode];
308 static const char *snd_pcm_state_name(snd_pcm_state_t state)
310 return snd_pcm_state_names[(__force int)state];
313 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
314 #include <linux/soundcard.h>
316 static const char *snd_pcm_oss_format_name(int format)
345 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
346 struct snd_info_buffer *buffer)
348 struct snd_pcm_info *info;
354 info = kmalloc(sizeof(*info), GFP_KERNEL);
358 err = snd_pcm_info(substream, info);
360 snd_iprintf(buffer, "error %d\n", err);
364 snd_iprintf(buffer, "card: %d\n", info->card);
365 snd_iprintf(buffer, "device: %d\n", info->device);
366 snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
367 snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
368 snd_iprintf(buffer, "id: %s\n", info->id);
369 snd_iprintf(buffer, "name: %s\n", info->name);
370 snd_iprintf(buffer, "subname: %s\n", info->subname);
371 snd_iprintf(buffer, "class: %d\n", info->dev_class);
372 snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
373 snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
374 snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
378 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
379 struct snd_info_buffer *buffer)
381 snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
385 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
386 struct snd_info_buffer *buffer)
388 snd_pcm_proc_info_read(entry->private_data, buffer);
391 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
392 struct snd_info_buffer *buffer)
394 struct snd_pcm_substream *substream = entry->private_data;
395 struct snd_pcm_runtime *runtime;
397 mutex_lock(&substream->pcm->open_mutex);
398 runtime = substream->runtime;
400 snd_iprintf(buffer, "closed\n");
403 if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
404 snd_iprintf(buffer, "no setup\n");
407 snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
408 snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
409 snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
410 snd_iprintf(buffer, "channels: %u\n", runtime->channels);
411 snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
412 snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
413 snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
414 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
415 if (substream->oss.oss) {
416 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
417 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
418 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
419 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
420 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
421 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
425 mutex_unlock(&substream->pcm->open_mutex);
428 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
429 struct snd_info_buffer *buffer)
431 struct snd_pcm_substream *substream = entry->private_data;
432 struct snd_pcm_runtime *runtime;
434 mutex_lock(&substream->pcm->open_mutex);
435 runtime = substream->runtime;
437 snd_iprintf(buffer, "closed\n");
440 if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
441 snd_iprintf(buffer, "no setup\n");
444 snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
445 snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
446 snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
447 snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
448 snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
449 snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
450 snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
451 snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
453 mutex_unlock(&substream->pcm->open_mutex);
456 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
457 struct snd_info_buffer *buffer)
459 struct snd_pcm_substream *substream = entry->private_data;
460 struct snd_pcm_runtime *runtime;
461 struct snd_pcm_status status;
464 mutex_lock(&substream->pcm->open_mutex);
465 runtime = substream->runtime;
467 snd_iprintf(buffer, "closed\n");
470 memset(&status, 0, sizeof(status));
471 err = snd_pcm_status(substream, &status);
473 snd_iprintf(buffer, "error %d\n", err);
476 snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
477 snd_iprintf(buffer, "owner_pid : %d\n", pid_vnr(substream->pid));
478 snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
479 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
480 snd_iprintf(buffer, "tstamp : %ld.%09ld\n",
481 status.tstamp.tv_sec, status.tstamp.tv_nsec);
482 snd_iprintf(buffer, "delay : %ld\n", status.delay);
483 snd_iprintf(buffer, "avail : %ld\n", status.avail);
484 snd_iprintf(buffer, "avail_max : %ld\n", status.avail_max);
485 snd_iprintf(buffer, "-----\n");
486 snd_iprintf(buffer, "hw_ptr : %ld\n", runtime->status->hw_ptr);
487 snd_iprintf(buffer, "appl_ptr : %ld\n", runtime->control->appl_ptr);
489 mutex_unlock(&substream->pcm->open_mutex);
492 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
493 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
494 struct snd_info_buffer *buffer)
496 struct snd_pcm_substream *substream = entry->private_data;
498 snd_pcm_stop_xrun(substream);
501 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
502 struct snd_info_buffer *buffer)
504 struct snd_pcm_str *pstr = entry->private_data;
505 snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
508 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
509 struct snd_info_buffer *buffer)
511 struct snd_pcm_str *pstr = entry->private_data;
513 if (!snd_info_get_line(buffer, line, sizeof(line)))
514 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
518 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
520 struct snd_pcm *pcm = pstr->pcm;
521 struct snd_info_entry *entry;
524 sprintf(name, "pcm%i%c", pcm->device,
525 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
526 entry = snd_info_create_card_entry(pcm->card, name,
527 pcm->card->proc_root);
530 entry->mode = S_IFDIR | 0555;
531 if (snd_info_register(entry) < 0) {
532 snd_info_free_entry(entry);
535 pstr->proc_root = entry;
536 entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
538 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
539 if (snd_info_register(entry) < 0) {
540 snd_info_free_entry(entry);
544 pstr->proc_info_entry = entry;
546 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
547 entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
550 entry->c.text.read = snd_pcm_xrun_debug_read;
551 entry->c.text.write = snd_pcm_xrun_debug_write;
553 entry->private_data = pstr;
554 if (snd_info_register(entry) < 0) {
555 snd_info_free_entry(entry);
559 pstr->proc_xrun_debug_entry = entry;
564 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
566 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
567 snd_info_free_entry(pstr->proc_xrun_debug_entry);
568 pstr->proc_xrun_debug_entry = NULL;
570 snd_info_free_entry(pstr->proc_info_entry);
571 pstr->proc_info_entry = NULL;
572 snd_info_free_entry(pstr->proc_root);
573 pstr->proc_root = NULL;
577 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
579 struct snd_info_entry *entry;
580 struct snd_card *card;
583 card = substream->pcm->card;
585 sprintf(name, "sub%i", substream->number);
586 entry = snd_info_create_card_entry(card, name,
587 substream->pstr->proc_root);
590 entry->mode = S_IFDIR | 0555;
591 if (snd_info_register(entry) < 0) {
592 snd_info_free_entry(entry);
595 substream->proc_root = entry;
596 entry = snd_info_create_card_entry(card, "info", substream->proc_root);
598 snd_info_set_text_ops(entry, substream,
599 snd_pcm_substream_proc_info_read);
600 if (snd_info_register(entry) < 0) {
601 snd_info_free_entry(entry);
605 substream->proc_info_entry = entry;
606 entry = snd_info_create_card_entry(card, "hw_params",
607 substream->proc_root);
609 snd_info_set_text_ops(entry, substream,
610 snd_pcm_substream_proc_hw_params_read);
611 if (snd_info_register(entry) < 0) {
612 snd_info_free_entry(entry);
616 substream->proc_hw_params_entry = entry;
617 entry = snd_info_create_card_entry(card, "sw_params",
618 substream->proc_root);
620 snd_info_set_text_ops(entry, substream,
621 snd_pcm_substream_proc_sw_params_read);
622 if (snd_info_register(entry) < 0) {
623 snd_info_free_entry(entry);
627 substream->proc_sw_params_entry = entry;
628 entry = snd_info_create_card_entry(card, "status",
629 substream->proc_root);
631 snd_info_set_text_ops(entry, substream,
632 snd_pcm_substream_proc_status_read);
633 if (snd_info_register(entry) < 0) {
634 snd_info_free_entry(entry);
638 substream->proc_status_entry = entry;
640 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
641 entry = snd_info_create_card_entry(card, "xrun_injection",
642 substream->proc_root);
644 entry->private_data = substream;
645 entry->c.text.read = NULL;
646 entry->c.text.write = snd_pcm_xrun_injection_write;
647 entry->mode = S_IFREG | 0200;
648 if (snd_info_register(entry) < 0) {
649 snd_info_free_entry(entry);
653 substream->proc_xrun_injection_entry = entry;
654 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
659 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
661 snd_info_free_entry(substream->proc_info_entry);
662 substream->proc_info_entry = NULL;
663 snd_info_free_entry(substream->proc_hw_params_entry);
664 substream->proc_hw_params_entry = NULL;
665 snd_info_free_entry(substream->proc_sw_params_entry);
666 substream->proc_sw_params_entry = NULL;
667 snd_info_free_entry(substream->proc_status_entry);
668 substream->proc_status_entry = NULL;
669 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
670 snd_info_free_entry(substream->proc_xrun_injection_entry);
671 substream->proc_xrun_injection_entry = NULL;
673 snd_info_free_entry(substream->proc_root);
674 substream->proc_root = NULL;
677 #else /* !CONFIG_SND_VERBOSE_PROCFS */
678 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
679 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
680 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
681 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
682 #endif /* CONFIG_SND_VERBOSE_PROCFS */
684 static const struct attribute_group *pcm_dev_attr_groups[];
687 * snd_pcm_new_stream - create a new PCM stream
688 * @pcm: the pcm instance
689 * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
690 * @substream_count: the number of substreams
692 * Creates a new stream for the pcm.
693 * The corresponding stream on the pcm must have been empty before
694 * calling this, i.e. zero must be given to the argument of
697 * Return: Zero if successful, or a negative error code on failure.
699 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
702 struct snd_pcm_str *pstr = &pcm->streams[stream];
703 struct snd_pcm_substream *substream, *prev;
705 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
706 mutex_init(&pstr->oss.setup_mutex);
708 pstr->stream = stream;
710 pstr->substream_count = substream_count;
711 if (!substream_count)
714 snd_device_initialize(&pstr->dev, pcm->card);
715 pstr->dev.groups = pcm_dev_attr_groups;
716 dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
717 stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
719 if (!pcm->internal) {
720 err = snd_pcm_stream_proc_init(pstr);
722 pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
727 for (idx = 0, prev = NULL; idx < substream_count; idx++) {
728 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
731 substream->pcm = pcm;
732 substream->pstr = pstr;
733 substream->number = idx;
734 substream->stream = stream;
735 sprintf(substream->name, "subdevice #%i", idx);
736 substream->buffer_bytes_max = UINT_MAX;
738 pstr->substream = substream;
740 prev->next = substream;
742 if (!pcm->internal) {
743 err = snd_pcm_substream_proc_init(substream);
746 "Error in snd_pcm_stream_proc_init\n");
748 pstr->substream = NULL;
755 substream->group = &substream->self_group;
756 spin_lock_init(&substream->self_group.lock);
757 mutex_init(&substream->self_group.mutex);
758 INIT_LIST_HEAD(&substream->self_group.substreams);
759 list_add_tail(&substream->link_list, &substream->self_group.substreams);
760 atomic_set(&substream->mmap_count, 0);
765 EXPORT_SYMBOL(snd_pcm_new_stream);
767 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
768 int playback_count, int capture_count, bool internal,
769 struct snd_pcm **rpcm)
773 static struct snd_device_ops ops = {
774 .dev_free = snd_pcm_dev_free,
775 .dev_register = snd_pcm_dev_register,
776 .dev_disconnect = snd_pcm_dev_disconnect,
778 static struct snd_device_ops internal_ops = {
779 .dev_free = snd_pcm_dev_free,
782 if (snd_BUG_ON(!card))
786 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
790 pcm->device = device;
791 pcm->internal = internal;
792 mutex_init(&pcm->open_mutex);
793 init_waitqueue_head(&pcm->open_wait);
794 INIT_LIST_HEAD(&pcm->list);
796 strlcpy(pcm->id, id, sizeof(pcm->id));
798 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
803 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
807 err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
808 internal ? &internal_ops : &ops);
822 * snd_pcm_new - create a new PCM instance
823 * @card: the card instance
825 * @device: the device index (zero based)
826 * @playback_count: the number of substreams for playback
827 * @capture_count: the number of substreams for capture
828 * @rpcm: the pointer to store the new pcm instance
830 * Creates a new PCM instance.
832 * The pcm operators have to be set afterwards to the new instance
833 * via snd_pcm_set_ops().
835 * Return: Zero if successful, or a negative error code on failure.
837 int snd_pcm_new(struct snd_card *card, const char *id, int device,
838 int playback_count, int capture_count, struct snd_pcm **rpcm)
840 return _snd_pcm_new(card, id, device, playback_count, capture_count,
843 EXPORT_SYMBOL(snd_pcm_new);
846 * snd_pcm_new_internal - create a new internal PCM instance
847 * @card: the card instance
849 * @device: the device index (zero based - shared with normal PCMs)
850 * @playback_count: the number of substreams for playback
851 * @capture_count: the number of substreams for capture
852 * @rpcm: the pointer to store the new pcm instance
854 * Creates a new internal PCM instance with no userspace device or procfs
855 * entries. This is used by ASoC Back End PCMs in order to create a PCM that
856 * will only be used internally by kernel drivers. i.e. it cannot be opened
857 * by userspace. It provides existing ASoC components drivers with a substream
858 * and access to any private data.
860 * The pcm operators have to be set afterwards to the new instance
861 * via snd_pcm_set_ops().
863 * Return: Zero if successful, or a negative error code on failure.
865 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
866 int playback_count, int capture_count,
867 struct snd_pcm **rpcm)
869 return _snd_pcm_new(card, id, device, playback_count, capture_count,
872 EXPORT_SYMBOL(snd_pcm_new_internal);
874 static void free_chmap(struct snd_pcm_str *pstr)
876 if (pstr->chmap_kctl) {
877 struct snd_card *card = pstr->pcm->card;
879 down_write(&card->controls_rwsem);
880 snd_ctl_remove(card, pstr->chmap_kctl);
881 up_write(&card->controls_rwsem);
882 pstr->chmap_kctl = NULL;
886 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
888 struct snd_pcm_substream *substream, *substream_next;
889 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
890 struct snd_pcm_oss_setup *setup, *setupn;
892 substream = pstr->substream;
894 substream_next = substream->next;
895 snd_pcm_timer_done(substream);
896 snd_pcm_substream_proc_done(substream);
898 substream = substream_next;
900 snd_pcm_stream_proc_done(pstr);
901 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
902 for (setup = pstr->oss.setup_list; setup; setup = setupn) {
903 setupn = setup->next;
904 kfree(setup->task_name);
909 if (pstr->substream_count)
910 put_device(&pstr->dev);
913 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
914 #define pcm_call_notify(pcm, call) \
916 struct snd_pcm_notify *_notify; \
917 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
918 _notify->call(pcm); \
921 #define pcm_call_notify(pcm, call) do {} while (0)
924 static int snd_pcm_free(struct snd_pcm *pcm)
929 pcm_call_notify(pcm, n_unregister);
930 if (pcm->private_free)
931 pcm->private_free(pcm);
932 snd_pcm_lib_preallocate_free_for_all(pcm);
933 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
934 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
939 static int snd_pcm_dev_free(struct snd_device *device)
941 struct snd_pcm *pcm = device->device_data;
942 return snd_pcm_free(pcm);
945 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
947 struct snd_pcm_substream **rsubstream)
949 struct snd_pcm_str * pstr;
950 struct snd_pcm_substream *substream;
951 struct snd_pcm_runtime *runtime;
952 struct snd_card *card;
953 int prefer_subdevice;
956 if (snd_BUG_ON(!pcm || !rsubstream))
958 if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
959 stream != SNDRV_PCM_STREAM_CAPTURE))
962 pstr = &pcm->streams[stream];
963 if (pstr->substream == NULL || pstr->substream_count == 0)
967 prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
969 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
970 int opposite = !stream;
972 for (substream = pcm->streams[opposite].substream; substream;
973 substream = substream->next) {
974 if (SUBSTREAM_BUSY(substream))
979 if (file->f_flags & O_APPEND) {
980 if (prefer_subdevice < 0) {
981 if (pstr->substream_count > 1)
982 return -EINVAL; /* must be unique */
983 substream = pstr->substream;
985 for (substream = pstr->substream; substream;
986 substream = substream->next)
987 if (substream->number == prefer_subdevice)
992 if (! SUBSTREAM_BUSY(substream))
994 substream->ref_count++;
995 *rsubstream = substream;
999 for (substream = pstr->substream; substream; substream = substream->next) {
1000 if (!SUBSTREAM_BUSY(substream) &&
1001 (prefer_subdevice == -1 ||
1002 substream->number == prefer_subdevice))
1005 if (substream == NULL)
1008 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
1009 if (runtime == NULL)
1012 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
1013 runtime->status = snd_malloc_pages(size, GFP_KERNEL);
1014 if (runtime->status == NULL) {
1018 memset((void*)runtime->status, 0, size);
1020 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
1021 runtime->control = snd_malloc_pages(size, GFP_KERNEL);
1022 if (runtime->control == NULL) {
1023 snd_free_pages((void*)runtime->status,
1024 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1028 memset((void*)runtime->control, 0, size);
1030 init_waitqueue_head(&runtime->sleep);
1031 init_waitqueue_head(&runtime->tsleep);
1033 runtime->status->state = SNDRV_PCM_STATE_OPEN;
1034 mutex_init(&runtime->buffer_mutex);
1035 atomic_set(&runtime->buffer_accessing, 0);
1037 substream->runtime = runtime;
1038 substream->private_data = pcm->private_data;
1039 substream->ref_count = 1;
1040 substream->f_flags = file->f_flags;
1041 substream->pid = get_pid(task_pid(current));
1042 pstr->substream_opened++;
1043 *rsubstream = substream;
1047 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1049 struct snd_pcm_runtime *runtime;
1051 if (PCM_RUNTIME_CHECK(substream))
1053 runtime = substream->runtime;
1054 if (runtime->private_free != NULL)
1055 runtime->private_free(runtime);
1056 snd_free_pages((void*)runtime->status,
1057 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1058 snd_free_pages((void*)runtime->control,
1059 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1060 kfree(runtime->hw_constraints.rules);
1061 /* Avoid concurrent access to runtime via PCM timer interface */
1062 if (substream->timer)
1063 spin_lock_irq(&substream->timer->lock);
1064 substream->runtime = NULL;
1065 if (substream->timer)
1066 spin_unlock_irq(&substream->timer->lock);
1067 mutex_destroy(&runtime->buffer_mutex);
1069 put_pid(substream->pid);
1070 substream->pid = NULL;
1071 substream->pstr->substream_opened--;
1074 static ssize_t show_pcm_class(struct device *dev,
1075 struct device_attribute *attr, char *buf)
1077 struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
1078 struct snd_pcm *pcm = pstr->pcm;
1080 static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1081 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1082 [SNDRV_PCM_CLASS_MULTI] = "multi",
1083 [SNDRV_PCM_CLASS_MODEM] = "modem",
1084 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1087 if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1090 str = strs[pcm->dev_class];
1091 return snprintf(buf, PAGE_SIZE, "%s\n", str);
1094 static DEVICE_ATTR(pcm_class, 0444, show_pcm_class, NULL);
1095 static struct attribute *pcm_dev_attrs[] = {
1096 &dev_attr_pcm_class.attr,
1100 static const struct attribute_group pcm_dev_attr_group = {
1101 .attrs = pcm_dev_attrs,
1104 static const struct attribute_group *pcm_dev_attr_groups[] = {
1105 &pcm_dev_attr_group,
1109 static int snd_pcm_dev_register(struct snd_device *device)
1112 struct snd_pcm_substream *substream;
1113 struct snd_pcm *pcm;
1115 if (snd_BUG_ON(!device || !device->device_data))
1117 pcm = device->device_data;
1119 mutex_lock(®ister_mutex);
1120 err = snd_pcm_add(pcm);
1123 for (cidx = 0; cidx < 2; cidx++) {
1125 if (pcm->streams[cidx].substream == NULL)
1128 case SNDRV_PCM_STREAM_PLAYBACK:
1129 devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1131 case SNDRV_PCM_STREAM_CAPTURE:
1132 devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1136 err = snd_register_device(devtype, pcm->card, pcm->device,
1137 &snd_pcm_f_ops[cidx], pcm,
1138 &pcm->streams[cidx].dev);
1140 list_del_init(&pcm->list);
1144 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1145 snd_pcm_timer_init(substream);
1148 pcm_call_notify(pcm, n_register);
1151 mutex_unlock(®ister_mutex);
1155 static int snd_pcm_dev_disconnect(struct snd_device *device)
1157 struct snd_pcm *pcm = device->device_data;
1158 struct snd_pcm_substream *substream;
1161 mutex_lock(®ister_mutex);
1162 mutex_lock(&pcm->open_mutex);
1163 wake_up(&pcm->open_wait);
1164 list_del_init(&pcm->list);
1165 for (cidx = 0; cidx < 2; cidx++) {
1166 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1167 snd_pcm_stream_lock_irq(substream);
1168 if (substream->runtime) {
1169 if (snd_pcm_running(substream))
1170 snd_pcm_stop(substream,
1171 SNDRV_PCM_STATE_DISCONNECTED);
1172 /* to be sure, set the state unconditionally */
1173 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1174 wake_up(&substream->runtime->sleep);
1175 wake_up(&substream->runtime->tsleep);
1177 snd_pcm_stream_unlock_irq(substream);
1181 pcm_call_notify(pcm, n_disconnect);
1182 for (cidx = 0; cidx < 2; cidx++) {
1183 snd_unregister_device(&pcm->streams[cidx].dev);
1184 free_chmap(&pcm->streams[cidx]);
1186 mutex_unlock(&pcm->open_mutex);
1187 mutex_unlock(®ister_mutex);
1191 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1193 * snd_pcm_notify - Add/remove the notify list
1194 * @notify: PCM notify list
1195 * @nfree: 0 = register, 1 = unregister
1197 * This adds the given notifier to the global list so that the callback is
1198 * called for each registered PCM devices. This exists only for PCM OSS
1199 * emulation, so far.
1201 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1203 struct snd_pcm *pcm;
1205 if (snd_BUG_ON(!notify ||
1206 !notify->n_register ||
1207 !notify->n_unregister ||
1208 !notify->n_disconnect))
1210 mutex_lock(®ister_mutex);
1212 list_del(¬ify->list);
1213 list_for_each_entry(pcm, &snd_pcm_devices, list)
1214 notify->n_unregister(pcm);
1216 list_add_tail(¬ify->list, &snd_pcm_notify_list);
1217 list_for_each_entry(pcm, &snd_pcm_devices, list)
1218 notify->n_register(pcm);
1220 mutex_unlock(®ister_mutex);
1223 EXPORT_SYMBOL(snd_pcm_notify);
1224 #endif /* CONFIG_SND_PCM_OSS */
1226 #ifdef CONFIG_SND_PROC_FS
1231 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1232 struct snd_info_buffer *buffer)
1234 struct snd_pcm *pcm;
1236 mutex_lock(®ister_mutex);
1237 list_for_each_entry(pcm, &snd_pcm_devices, list) {
1238 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1239 pcm->card->number, pcm->device, pcm->id, pcm->name);
1240 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1241 snd_iprintf(buffer, " : playback %i",
1242 pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1243 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1244 snd_iprintf(buffer, " : capture %i",
1245 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1246 snd_iprintf(buffer, "\n");
1248 mutex_unlock(®ister_mutex);
1251 static struct snd_info_entry *snd_pcm_proc_entry;
1253 static void snd_pcm_proc_init(void)
1255 struct snd_info_entry *entry;
1257 entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1259 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1260 if (snd_info_register(entry) < 0) {
1261 snd_info_free_entry(entry);
1265 snd_pcm_proc_entry = entry;
1268 static void snd_pcm_proc_done(void)
1270 snd_info_free_entry(snd_pcm_proc_entry);
1273 #else /* !CONFIG_SND_PROC_FS */
1274 #define snd_pcm_proc_init()
1275 #define snd_pcm_proc_done()
1276 #endif /* CONFIG_SND_PROC_FS */
1283 static int __init alsa_pcm_init(void)
1285 snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1286 snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1287 snd_pcm_proc_init();
1291 static void __exit alsa_pcm_exit(void)
1293 snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1294 snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1295 snd_pcm_proc_done();
1298 module_init(alsa_pcm_init)
1299 module_exit(alsa_pcm_exit)