1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Digital Audio (PCM) abstract layer
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/init.h>
8#include <linux/slab.h>
9#include <linux/module.h>
10#include <linux/time.h>
11#include <linux/mutex.h>
12#include <linux/device.h>
13#include <linux/nospec.h>
14#include <sound/core.h>
15#include <sound/minors.h>
16#include <sound/pcm.h>
17#include <sound/timer.h>
18#include <sound/control.h>
19#include <sound/info.h>
20
21#include "pcm_local.h"
22
23MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
24MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
25MODULE_LICENSE("GPL");
26
27static LIST_HEAD(snd_pcm_devices);
28static DEFINE_MUTEX(register_mutex);
29#if IS_ENABLED(CONFIG_SND_PCM_OSS)
30static LIST_HEAD(snd_pcm_notify_list);
31#endif
32
33static int snd_pcm_free(struct snd_pcm *pcm);
34static int snd_pcm_dev_free(struct snd_device *device);
35static int snd_pcm_dev_register(struct snd_device *device);
36static int snd_pcm_dev_disconnect(struct snd_device *device);
37
38static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
39{
40 struct snd_pcm *pcm;
41
42 list_for_each_entry(pcm, &snd_pcm_devices, list) {
43 if (pcm->card == card && pcm->device == device)
44 return pcm;
45 }
46 return NULL;
47}
48
49static int snd_pcm_next(struct snd_card *card, int device)
50{
51 struct snd_pcm *pcm;
52
53 list_for_each_entry(pcm, &snd_pcm_devices, list) {
54 if (pcm->card == card && pcm->device > device)
55 return pcm->device;
56 else if (pcm->card->number > card->number)
57 return -1;
58 }
59 return -1;
60}
61
62static int snd_pcm_add(struct snd_pcm *newpcm)
63{
64 struct snd_pcm *pcm;
65
66 if (newpcm->internal)
67 return 0;
68
69 list_for_each_entry(pcm, &snd_pcm_devices, list) {
70 if (pcm->card == newpcm->card && pcm->device == newpcm->device)
71 return -EBUSY;
72 if (pcm->card->number > newpcm->card->number ||
73 (pcm->card == newpcm->card &&
74 pcm->device > newpcm->device)) {
75 list_add(new: &newpcm->list, head: pcm->list.prev);
76 return 0;
77 }
78 }
79 list_add_tail(new: &newpcm->list, head: &snd_pcm_devices);
80 return 0;
81}
82
83static int snd_pcm_control_ioctl(struct snd_card *card,
84 struct snd_ctl_file *control,
85 unsigned int cmd, unsigned long arg)
86{
87 switch (cmd) {
88 case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
89 {
90 int device;
91
92 if (get_user(device, (int __user *)arg))
93 return -EFAULT;
94 scoped_guard(mutex, &register_mutex)
95 device = snd_pcm_next(card, device);
96 if (put_user(device, (int __user *)arg))
97 return -EFAULT;
98 return 0;
99 }
100 case SNDRV_CTL_IOCTL_PCM_INFO:
101 {
102 struct snd_pcm_info __user *info;
103 unsigned int device, subdevice;
104 int stream;
105 struct snd_pcm *pcm;
106 struct snd_pcm_str *pstr;
107 struct snd_pcm_substream *substream;
108
109 info = (struct snd_pcm_info __user *)arg;
110 if (get_user(device, &info->device))
111 return -EFAULT;
112 if (get_user(stream, &info->stream))
113 return -EFAULT;
114 if (stream < 0 || stream > 1)
115 return -EINVAL;
116 stream = array_index_nospec(stream, 2);
117 if (get_user(subdevice, &info->subdevice))
118 return -EFAULT;
119 guard(mutex)(T: &register_mutex);
120 pcm = snd_pcm_get(card, device);
121 if (pcm == NULL)
122 return -ENXIO;
123 pstr = &pcm->streams[stream];
124 if (pstr->substream_count == 0)
125 return -ENOENT;
126 if (subdevice >= pstr->substream_count)
127 return -ENXIO;
128 for (substream = pstr->substream; substream;
129 substream = substream->next)
130 if (substream->number == (int)subdevice)
131 break;
132 if (substream == NULL)
133 return -ENXIO;
134 guard(mutex)(T: &pcm->open_mutex);
135 return snd_pcm_info_user(substream, info);
136 }
137 case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
138 {
139 int val;
140
141 if (get_user(val, (int __user *)arg))
142 return -EFAULT;
143 control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
144 return 0;
145 }
146 }
147 return -ENOIOCTLCMD;
148}
149
150#define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
151
152static const char * const snd_pcm_format_names[] = {
153 FORMAT(S8),
154 FORMAT(U8),
155 FORMAT(S16_LE),
156 FORMAT(S16_BE),
157 FORMAT(U16_LE),
158 FORMAT(U16_BE),
159 FORMAT(S24_LE),
160 FORMAT(S24_BE),
161 FORMAT(U24_LE),
162 FORMAT(U24_BE),
163 FORMAT(S32_LE),
164 FORMAT(S32_BE),
165 FORMAT(U32_LE),
166 FORMAT(U32_BE),
167 FORMAT(FLOAT_LE),
168 FORMAT(FLOAT_BE),
169 FORMAT(FLOAT64_LE),
170 FORMAT(FLOAT64_BE),
171 FORMAT(IEC958_SUBFRAME_LE),
172 FORMAT(IEC958_SUBFRAME_BE),
173 FORMAT(MU_LAW),
174 FORMAT(A_LAW),
175 FORMAT(IMA_ADPCM),
176 FORMAT(MPEG),
177 FORMAT(GSM),
178 FORMAT(SPECIAL),
179 FORMAT(S24_3LE),
180 FORMAT(S24_3BE),
181 FORMAT(U24_3LE),
182 FORMAT(U24_3BE),
183 FORMAT(S20_3LE),
184 FORMAT(S20_3BE),
185 FORMAT(U20_3LE),
186 FORMAT(U20_3BE),
187 FORMAT(S18_3LE),
188 FORMAT(S18_3BE),
189 FORMAT(U18_3LE),
190 FORMAT(U18_3BE),
191 FORMAT(G723_24),
192 FORMAT(G723_24_1B),
193 FORMAT(G723_40),
194 FORMAT(G723_40_1B),
195 FORMAT(DSD_U8),
196 FORMAT(DSD_U16_LE),
197 FORMAT(DSD_U32_LE),
198 FORMAT(DSD_U16_BE),
199 FORMAT(DSD_U32_BE),
200 FORMAT(S20_LE),
201 FORMAT(S20_BE),
202 FORMAT(U20_LE),
203 FORMAT(U20_BE),
204};
205
206/**
207 * snd_pcm_format_name - Return a name string for the given PCM format
208 * @format: PCM format
209 *
210 * Return: the format name string
211 */
212const char *snd_pcm_format_name(snd_pcm_format_t format)
213{
214 unsigned int format_num = (__force unsigned int)format;
215
216 if (format_num >= ARRAY_SIZE(snd_pcm_format_names) || !snd_pcm_format_names[format_num])
217 return "Unknown";
218 return snd_pcm_format_names[format_num];
219}
220EXPORT_SYMBOL_GPL(snd_pcm_format_name);
221
222#ifdef CONFIG_SND_VERBOSE_PROCFS
223
224#define STATE(v) [SNDRV_PCM_STATE_##v] = #v
225#define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
226#define READY(v) [SNDRV_PCM_READY_##v] = #v
227#define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
228#define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
229#define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
230#define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
231#define START(v) [SNDRV_PCM_START_##v] = #v
232#define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
233
234static const char * const snd_pcm_stream_names[] = {
235 STREAM(PLAYBACK),
236 STREAM(CAPTURE),
237};
238
239static const char * const snd_pcm_state_names[] = {
240 STATE(OPEN),
241 STATE(SETUP),
242 STATE(PREPARED),
243 STATE(RUNNING),
244 STATE(XRUN),
245 STATE(DRAINING),
246 STATE(PAUSED),
247 STATE(SUSPENDED),
248 STATE(DISCONNECTED),
249};
250
251static const char * const snd_pcm_access_names[] = {
252 ACCESS(MMAP_INTERLEAVED),
253 ACCESS(MMAP_NONINTERLEAVED),
254 ACCESS(MMAP_COMPLEX),
255 ACCESS(RW_INTERLEAVED),
256 ACCESS(RW_NONINTERLEAVED),
257};
258
259static const char * const snd_pcm_subformat_names[] = {
260 SUBFORMAT(STD),
261 SUBFORMAT(MSBITS_MAX),
262 SUBFORMAT(MSBITS_20),
263 SUBFORMAT(MSBITS_24),
264};
265
266static const char * const snd_pcm_tstamp_mode_names[] = {
267 TSTAMP(NONE),
268 TSTAMP(ENABLE),
269};
270
271static const char *snd_pcm_stream_name(int stream)
272{
273 return snd_pcm_stream_names[stream];
274}
275
276static const char *snd_pcm_access_name(snd_pcm_access_t access)
277{
278 return snd_pcm_access_names[(__force int)access];
279}
280
281static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
282{
283 return snd_pcm_subformat_names[(__force int)subformat];
284}
285
286static const char *snd_pcm_tstamp_mode_name(int mode)
287{
288 return snd_pcm_tstamp_mode_names[mode];
289}
290
291static const char *snd_pcm_state_name(snd_pcm_state_t state)
292{
293 return snd_pcm_state_names[(__force int)state];
294}
295
296#if IS_ENABLED(CONFIG_SND_PCM_OSS)
297#include <linux/soundcard.h>
298
299static const char *snd_pcm_oss_format_name(int format)
300{
301 switch (format) {
302 case AFMT_MU_LAW:
303 return "MU_LAW";
304 case AFMT_A_LAW:
305 return "A_LAW";
306 case AFMT_IMA_ADPCM:
307 return "IMA_ADPCM";
308 case AFMT_U8:
309 return "U8";
310 case AFMT_S16_LE:
311 return "S16_LE";
312 case AFMT_S16_BE:
313 return "S16_BE";
314 case AFMT_S8:
315 return "S8";
316 case AFMT_U16_LE:
317 return "U16_LE";
318 case AFMT_U16_BE:
319 return "U16_BE";
320 case AFMT_MPEG:
321 return "MPEG";
322 default:
323 return "unknown";
324 }
325}
326#endif
327
328static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
329 struct snd_info_buffer *buffer)
330{
331 struct snd_pcm_info *info __free(kfree) = NULL;
332 int err;
333
334 if (! substream)
335 return;
336
337 info = kmalloc(sizeof(*info), GFP_KERNEL);
338 if (!info)
339 return;
340
341 err = snd_pcm_info(substream, info);
342 if (err < 0) {
343 snd_iprintf(buffer, "error %d\n", err);
344 return;
345 }
346 snd_iprintf(buffer, "card: %d\n", info->card);
347 snd_iprintf(buffer, "device: %d\n", info->device);
348 snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
349 snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
350 snd_iprintf(buffer, "id: %s\n", info->id);
351 snd_iprintf(buffer, "name: %s\n", info->name);
352 snd_iprintf(buffer, "subname: %s\n", info->subname);
353 snd_iprintf(buffer, "class: %d\n", info->dev_class);
354 snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
355 snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
356 snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
357}
358
359static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
360 struct snd_info_buffer *buffer)
361{
362 snd_pcm_proc_info_read(substream: ((struct snd_pcm_str *)entry->private_data)->substream,
363 buffer);
364}
365
366static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
367 struct snd_info_buffer *buffer)
368{
369 snd_pcm_proc_info_read(substream: entry->private_data, buffer);
370}
371
372static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
373 struct snd_info_buffer *buffer)
374{
375 struct snd_pcm_substream *substream = entry->private_data;
376 struct snd_pcm_runtime *runtime;
377
378 guard(mutex)(T: &substream->pcm->open_mutex);
379 runtime = substream->runtime;
380 if (!runtime) {
381 snd_iprintf(buffer, "closed\n");
382 return;
383 }
384 if (runtime->state == SNDRV_PCM_STATE_OPEN) {
385 snd_iprintf(buffer, "no setup\n");
386 return;
387 }
388 snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
389 snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
390 snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
391 snd_iprintf(buffer, "channels: %u\n", runtime->channels);
392 snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
393 snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
394 snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
395#if IS_ENABLED(CONFIG_SND_PCM_OSS)
396 if (substream->oss.oss) {
397 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
398 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
399 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
400 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
401 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
402 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
403 }
404#endif
405}
406
407static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
408 struct snd_info_buffer *buffer)
409{
410 struct snd_pcm_substream *substream = entry->private_data;
411 struct snd_pcm_runtime *runtime;
412
413 guard(mutex)(T: &substream->pcm->open_mutex);
414 runtime = substream->runtime;
415 if (!runtime) {
416 snd_iprintf(buffer, "closed\n");
417 return;
418 }
419 if (runtime->state == SNDRV_PCM_STATE_OPEN) {
420 snd_iprintf(buffer, "no setup\n");
421 return;
422 }
423 snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
424 snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
425 snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
426 snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
427 snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
428 snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
429 snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
430 snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
431}
432
433static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
434 struct snd_info_buffer *buffer)
435{
436 struct snd_pcm_substream *substream = entry->private_data;
437 struct snd_pcm_runtime *runtime;
438 struct snd_pcm_status64 status;
439 int err;
440
441 guard(mutex)(T: &substream->pcm->open_mutex);
442 runtime = substream->runtime;
443 if (!runtime) {
444 snd_iprintf(buffer, "closed\n");
445 return;
446 }
447 memset(s: &status, c: 0, n: sizeof(status));
448 err = snd_pcm_status64(substream, status: &status);
449 if (err < 0) {
450 snd_iprintf(buffer, "error %d\n", err);
451 return;
452 }
453 snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
454 snd_iprintf(buffer, "owner_pid : %d\n", pid_vnr(substream->pid));
455 snd_iprintf(buffer, "trigger_time: %lld.%09lld\n",
456 status.trigger_tstamp_sec, status.trigger_tstamp_nsec);
457 snd_iprintf(buffer, "tstamp : %lld.%09lld\n",
458 status.tstamp_sec, status.tstamp_nsec);
459 snd_iprintf(buffer, "delay : %ld\n", status.delay);
460 snd_iprintf(buffer, "avail : %ld\n", status.avail);
461 snd_iprintf(buffer, "avail_max : %ld\n", status.avail_max);
462 snd_iprintf(buffer, "-----\n");
463 snd_iprintf(buffer, "hw_ptr : %ld\n", runtime->status->hw_ptr);
464 snd_iprintf(buffer, "appl_ptr : %ld\n", runtime->control->appl_ptr);
465#ifdef CONFIG_SND_PCM_XRUN_DEBUG
466 snd_iprintf(buffer, "xrun_counter: %d\n", substream->xrun_counter);
467#endif
468}
469
470#ifdef CONFIG_SND_PCM_XRUN_DEBUG
471static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
472 struct snd_info_buffer *buffer)
473{
474 struct snd_pcm_substream *substream = entry->private_data;
475
476 snd_pcm_stop_xrun(substream);
477}
478
479static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
480 struct snd_info_buffer *buffer)
481{
482 struct snd_pcm_str *pstr = entry->private_data;
483 snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
484}
485
486static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
487 struct snd_info_buffer *buffer)
488{
489 struct snd_pcm_str *pstr = entry->private_data;
490 char line[64];
491 if (!snd_info_get_line(buffer, line, sizeof(line)))
492 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
493}
494#endif
495
496static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
497{
498 struct snd_pcm *pcm = pstr->pcm;
499 struct snd_info_entry *entry;
500 char name[16];
501
502 sprintf(buf: name, fmt: "pcm%i%c", pcm->device,
503 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
504 entry = snd_info_create_card_entry(card: pcm->card, name,
505 parent: pcm->card->proc_root);
506 if (!entry)
507 return -ENOMEM;
508 entry->mode = S_IFDIR | 0555;
509 pstr->proc_root = entry;
510 entry = snd_info_create_card_entry(card: pcm->card, name: "info", parent: pstr->proc_root);
511 if (entry)
512 snd_info_set_text_ops(entry, private_data: pstr, read: snd_pcm_stream_proc_info_read);
513#ifdef CONFIG_SND_PCM_XRUN_DEBUG
514 entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
515 pstr->proc_root);
516 if (entry) {
517 snd_info_set_text_ops(entry, pstr, snd_pcm_xrun_debug_read);
518 entry->c.text.write = snd_pcm_xrun_debug_write;
519 entry->mode |= 0200;
520 }
521#endif
522 return 0;
523}
524
525static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
526{
527 snd_info_free_entry(entry: pstr->proc_root);
528 pstr->proc_root = NULL;
529 return 0;
530}
531
532static struct snd_info_entry *
533create_substream_info_entry(struct snd_pcm_substream *substream,
534 const char *name,
535 void (*read)(struct snd_info_entry *,
536 struct snd_info_buffer *))
537{
538 struct snd_info_entry *entry;
539
540 entry = snd_info_create_card_entry(card: substream->pcm->card, name,
541 parent: substream->proc_root);
542 if (entry)
543 snd_info_set_text_ops(entry, private_data: substream, read);
544 return entry;
545}
546
547static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
548{
549 struct snd_info_entry *entry;
550 struct snd_card *card;
551 char name[16];
552
553 card = substream->pcm->card;
554
555 sprintf(buf: name, fmt: "sub%i", substream->number);
556 entry = snd_info_create_card_entry(card, name,
557 parent: substream->pstr->proc_root);
558 if (!entry)
559 return -ENOMEM;
560 entry->mode = S_IFDIR | 0555;
561 substream->proc_root = entry;
562
563 create_substream_info_entry(substream, name: "info",
564 read: snd_pcm_substream_proc_info_read);
565 create_substream_info_entry(substream, name: "hw_params",
566 read: snd_pcm_substream_proc_hw_params_read);
567 create_substream_info_entry(substream, name: "sw_params",
568 read: snd_pcm_substream_proc_sw_params_read);
569 create_substream_info_entry(substream, name: "status",
570 read: snd_pcm_substream_proc_status_read);
571
572#ifdef CONFIG_SND_PCM_XRUN_DEBUG
573 entry = create_substream_info_entry(substream, "xrun_injection", NULL);
574 if (entry) {
575 entry->c.text.write = snd_pcm_xrun_injection_write;
576 entry->mode = S_IFREG | 0200;
577 }
578#endif /* CONFIG_SND_PCM_XRUN_DEBUG */
579
580 return 0;
581}
582
583#else /* !CONFIG_SND_VERBOSE_PROCFS */
584static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
585static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
586static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
587#endif /* CONFIG_SND_VERBOSE_PROCFS */
588
589static const struct attribute_group *pcm_dev_attr_groups[];
590
591/*
592 * PM callbacks: we need to deal only with suspend here, as the resume is
593 * triggered either from user-space or the driver's resume callback
594 */
595static int do_pcm_suspend(struct device *dev)
596{
597 struct snd_pcm_str *pstr = dev_get_drvdata(dev);
598
599 if (!pstr->pcm->no_device_suspend)
600 snd_pcm_suspend_all(pcm: pstr->pcm);
601 return 0;
602}
603
604static const struct dev_pm_ops pcm_dev_pm_ops = {
605 SYSTEM_SLEEP_PM_OPS(do_pcm_suspend, NULL)
606};
607
608/* device type for PCM -- basically only for passing PM callbacks */
609static const struct device_type pcm_dev_type = {
610 .name = "pcm",
611 .pm = &pcm_dev_pm_ops,
612};
613
614/**
615 * snd_pcm_new_stream - create a new PCM stream
616 * @pcm: the pcm instance
617 * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
618 * @substream_count: the number of substreams
619 *
620 * Creates a new stream for the pcm.
621 * The corresponding stream on the pcm must have been empty before
622 * calling this, i.e. zero must be given to the argument of
623 * snd_pcm_new().
624 *
625 * Return: Zero if successful, or a negative error code on failure.
626 */
627int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
628{
629 int idx, err;
630 struct snd_pcm_str *pstr = &pcm->streams[stream];
631 struct snd_pcm_substream *substream, *prev;
632
633#if IS_ENABLED(CONFIG_SND_PCM_OSS)
634 mutex_init(&pstr->oss.setup_mutex);
635#endif
636 pstr->stream = stream;
637 pstr->pcm = pcm;
638 pstr->substream_count = substream_count;
639 if (!substream_count)
640 return 0;
641
642 err = snd_device_alloc(dev_p: &pstr->dev, card: pcm->card);
643 if (err < 0)
644 return err;
645 dev_set_name(dev: pstr->dev, name: "pcmC%iD%i%c", pcm->card->number, pcm->device,
646 stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
647 pstr->dev->groups = pcm_dev_attr_groups;
648 pstr->dev->type = &pcm_dev_type;
649 dev_set_drvdata(dev: pstr->dev, data: pstr);
650
651 if (!pcm->internal) {
652 err = snd_pcm_stream_proc_init(pstr);
653 if (err < 0) {
654 pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
655 return err;
656 }
657 }
658 prev = NULL;
659 for (idx = 0, prev = NULL; idx < substream_count; idx++) {
660 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
661 if (!substream)
662 return -ENOMEM;
663 substream->pcm = pcm;
664 substream->pstr = pstr;
665 substream->number = idx;
666 substream->stream = stream;
667 sprintf(buf: substream->name, fmt: "subdevice #%i", idx);
668 substream->buffer_bytes_max = UINT_MAX;
669 if (prev == NULL)
670 pstr->substream = substream;
671 else
672 prev->next = substream;
673
674 if (!pcm->internal) {
675 err = snd_pcm_substream_proc_init(substream);
676 if (err < 0) {
677 pcm_err(pcm,
678 "Error in snd_pcm_stream_proc_init\n");
679 if (prev == NULL)
680 pstr->substream = NULL;
681 else
682 prev->next = NULL;
683 kfree(objp: substream);
684 return err;
685 }
686 }
687 substream->group = &substream->self_group;
688 snd_pcm_group_init(group: &substream->self_group);
689 list_add_tail(new: &substream->link_list, head: &substream->self_group.substreams);
690 atomic_set(v: &substream->mmap_count, i: 0);
691 prev = substream;
692 }
693 return 0;
694}
695EXPORT_SYMBOL(snd_pcm_new_stream);
696
697static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
698 int playback_count, int capture_count, bool internal,
699 struct snd_pcm **rpcm)
700{
701 struct snd_pcm *pcm;
702 int err;
703 static const struct snd_device_ops ops = {
704 .dev_free = snd_pcm_dev_free,
705 .dev_register = snd_pcm_dev_register,
706 .dev_disconnect = snd_pcm_dev_disconnect,
707 };
708 static const struct snd_device_ops internal_ops = {
709 .dev_free = snd_pcm_dev_free,
710 };
711
712 if (snd_BUG_ON(!card))
713 return -ENXIO;
714 if (rpcm)
715 *rpcm = NULL;
716 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
717 if (!pcm)
718 return -ENOMEM;
719 pcm->card = card;
720 pcm->device = device;
721 pcm->internal = internal;
722 mutex_init(&pcm->open_mutex);
723 init_waitqueue_head(&pcm->open_wait);
724 INIT_LIST_HEAD(list: &pcm->list);
725 if (id)
726 strscpy(pcm->id, id, sizeof(pcm->id));
727
728 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
729 playback_count);
730 if (err < 0)
731 goto free_pcm;
732
733 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
734 if (err < 0)
735 goto free_pcm;
736
737 err = snd_device_new(card, type: SNDRV_DEV_PCM, device_data: pcm,
738 ops: internal ? &internal_ops : &ops);
739 if (err < 0)
740 goto free_pcm;
741
742 if (rpcm)
743 *rpcm = pcm;
744 return 0;
745
746free_pcm:
747 snd_pcm_free(pcm);
748 return err;
749}
750
751/**
752 * snd_pcm_new - create a new PCM instance
753 * @card: the card instance
754 * @id: the id string
755 * @device: the device index (zero based)
756 * @playback_count: the number of substreams for playback
757 * @capture_count: the number of substreams for capture
758 * @rpcm: the pointer to store the new pcm instance
759 *
760 * Creates a new PCM instance.
761 *
762 * The pcm operators have to be set afterwards to the new instance
763 * via snd_pcm_set_ops().
764 *
765 * Return: Zero if successful, or a negative error code on failure.
766 */
767int snd_pcm_new(struct snd_card *card, const char *id, int device,
768 int playback_count, int capture_count, struct snd_pcm **rpcm)
769{
770 return _snd_pcm_new(card, id, device, playback_count, capture_count,
771 internal: false, rpcm);
772}
773EXPORT_SYMBOL(snd_pcm_new);
774
775/**
776 * snd_pcm_new_internal - create a new internal PCM instance
777 * @card: the card instance
778 * @id: the id string
779 * @device: the device index (zero based - shared with normal PCMs)
780 * @playback_count: the number of substreams for playback
781 * @capture_count: the number of substreams for capture
782 * @rpcm: the pointer to store the new pcm instance
783 *
784 * Creates a new internal PCM instance with no userspace device or procfs
785 * entries. This is used by ASoC Back End PCMs in order to create a PCM that
786 * will only be used internally by kernel drivers. i.e. it cannot be opened
787 * by userspace. It provides existing ASoC components drivers with a substream
788 * and access to any private data.
789 *
790 * The pcm operators have to be set afterwards to the new instance
791 * via snd_pcm_set_ops().
792 *
793 * Return: Zero if successful, or a negative error code on failure.
794 */
795int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
796 int playback_count, int capture_count,
797 struct snd_pcm **rpcm)
798{
799 return _snd_pcm_new(card, id, device, playback_count, capture_count,
800 internal: true, rpcm);
801}
802EXPORT_SYMBOL(snd_pcm_new_internal);
803
804static void free_chmap(struct snd_pcm_str *pstr)
805{
806 if (pstr->chmap_kctl) {
807 struct snd_card *card = pstr->pcm->card;
808
809 snd_ctl_remove(card, kcontrol: pstr->chmap_kctl);
810 pstr->chmap_kctl = NULL;
811 }
812}
813
814static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
815{
816 struct snd_pcm_substream *substream, *substream_next;
817#if IS_ENABLED(CONFIG_SND_PCM_OSS)
818 struct snd_pcm_oss_setup *setup, *setupn;
819#endif
820
821 /* free all proc files under the stream */
822 snd_pcm_stream_proc_done(pstr);
823
824 substream = pstr->substream;
825 while (substream) {
826 substream_next = substream->next;
827 snd_pcm_timer_done(substream);
828 kfree(objp: substream);
829 substream = substream_next;
830 }
831#if IS_ENABLED(CONFIG_SND_PCM_OSS)
832 for (setup = pstr->oss.setup_list; setup; setup = setupn) {
833 setupn = setup->next;
834 kfree(setup->task_name);
835 kfree(setup);
836 }
837#endif
838 free_chmap(pstr);
839 if (pstr->substream_count)
840 put_device(dev: pstr->dev);
841}
842
843#if IS_ENABLED(CONFIG_SND_PCM_OSS)
844#define pcm_call_notify(pcm, call) \
845 do { \
846 struct snd_pcm_notify *_notify; \
847 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
848 _notify->call(pcm); \
849 } while (0)
850#else
851#define pcm_call_notify(pcm, call) do {} while (0)
852#endif
853
854static int snd_pcm_free(struct snd_pcm *pcm)
855{
856 if (!pcm)
857 return 0;
858 if (!pcm->internal)
859 pcm_call_notify(pcm, n_unregister);
860 if (pcm->private_free)
861 pcm->private_free(pcm);
862 snd_pcm_lib_preallocate_free_for_all(pcm);
863 snd_pcm_free_stream(pstr: &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
864 snd_pcm_free_stream(pstr: &pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
865 kfree(objp: pcm);
866 return 0;
867}
868
869static int snd_pcm_dev_free(struct snd_device *device)
870{
871 struct snd_pcm *pcm = device->device_data;
872 return snd_pcm_free(pcm);
873}
874
875int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
876 struct file *file,
877 struct snd_pcm_substream **rsubstream)
878{
879 struct snd_pcm_str * pstr;
880 struct snd_pcm_substream *substream;
881 struct snd_pcm_runtime *runtime;
882 struct snd_card *card;
883 int prefer_subdevice;
884 size_t size;
885
886 if (snd_BUG_ON(!pcm || !rsubstream))
887 return -ENXIO;
888 if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
889 stream != SNDRV_PCM_STREAM_CAPTURE))
890 return -EINVAL;
891 *rsubstream = NULL;
892 pstr = &pcm->streams[stream];
893 if (pstr->substream == NULL || pstr->substream_count == 0)
894 return -ENODEV;
895
896 card = pcm->card;
897 prefer_subdevice = snd_ctl_get_preferred_subdevice(card, type: SND_CTL_SUBDEV_PCM);
898
899 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
900 int opposite = !stream;
901
902 for (substream = pcm->streams[opposite].substream; substream;
903 substream = substream->next) {
904 if (SUBSTREAM_BUSY(substream))
905 return -EAGAIN;
906 }
907 }
908
909 if (file->f_flags & O_APPEND) {
910 if (prefer_subdevice < 0) {
911 if (pstr->substream_count > 1)
912 return -EINVAL; /* must be unique */
913 substream = pstr->substream;
914 } else {
915 for (substream = pstr->substream; substream;
916 substream = substream->next)
917 if (substream->number == prefer_subdevice)
918 break;
919 }
920 if (! substream)
921 return -ENODEV;
922 if (! SUBSTREAM_BUSY(substream))
923 return -EBADFD;
924 substream->ref_count++;
925 *rsubstream = substream;
926 return 0;
927 }
928
929 for (substream = pstr->substream; substream; substream = substream->next) {
930 if (!SUBSTREAM_BUSY(substream) &&
931 (prefer_subdevice == -1 ||
932 substream->number == prefer_subdevice))
933 break;
934 }
935 if (substream == NULL)
936 return -EAGAIN;
937
938 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
939 if (runtime == NULL)
940 return -ENOMEM;
941
942 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
943 runtime->status = alloc_pages_exact(size, GFP_KERNEL);
944 if (runtime->status == NULL) {
945 kfree(objp: runtime);
946 return -ENOMEM;
947 }
948 memset(s: runtime->status, c: 0, n: size);
949
950 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
951 runtime->control = alloc_pages_exact(size, GFP_KERNEL);
952 if (runtime->control == NULL) {
953 free_pages_exact(virt: runtime->status,
954 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
955 kfree(objp: runtime);
956 return -ENOMEM;
957 }
958 memset(s: runtime->control, c: 0, n: size);
959
960 init_waitqueue_head(&runtime->sleep);
961 init_waitqueue_head(&runtime->tsleep);
962
963 __snd_pcm_set_state(runtime, SNDRV_PCM_STATE_OPEN);
964 mutex_init(&runtime->buffer_mutex);
965 atomic_set(v: &runtime->buffer_accessing, i: 0);
966
967 substream->runtime = runtime;
968 substream->private_data = pcm->private_data;
969 substream->ref_count = 1;
970 substream->f_flags = file->f_flags;
971 substream->pid = get_pid(pid: task_pid(current));
972 pstr->substream_opened++;
973 *rsubstream = substream;
974#ifdef CONFIG_SND_PCM_XRUN_DEBUG
975 substream->xrun_counter = 0;
976#endif /* CONFIG_SND_PCM_XRUN_DEBUG */
977 return 0;
978}
979
980void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
981{
982 struct snd_pcm_runtime *runtime;
983
984 if (PCM_RUNTIME_CHECK(substream))
985 return;
986 runtime = substream->runtime;
987 if (runtime->private_free != NULL)
988 runtime->private_free(runtime);
989 free_pages_exact(virt: runtime->status,
990 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
991 free_pages_exact(virt: runtime->control,
992 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
993 kfree(objp: runtime->hw_constraints.rules);
994 /* Avoid concurrent access to runtime via PCM timer interface */
995 if (substream->timer) {
996 scoped_guard(spinlock_irq, &substream->timer->lock)
997 substream->runtime = NULL;
998 } else {
999 substream->runtime = NULL;
1000 }
1001 mutex_destroy(lock: &runtime->buffer_mutex);
1002 snd_fasync_free(fasync: runtime->fasync);
1003 kfree(objp: runtime);
1004 put_pid(pid: substream->pid);
1005 substream->pid = NULL;
1006 substream->pstr->substream_opened--;
1007}
1008
1009static ssize_t pcm_class_show(struct device *dev,
1010 struct device_attribute *attr, char *buf)
1011{
1012 struct snd_pcm_str *pstr = dev_get_drvdata(dev);
1013 struct snd_pcm *pcm = pstr->pcm;
1014 const char *str;
1015 static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1016 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1017 [SNDRV_PCM_CLASS_MULTI] = "multi",
1018 [SNDRV_PCM_CLASS_MODEM] = "modem",
1019 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1020 };
1021
1022 if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1023 str = "none";
1024 else
1025 str = strs[pcm->dev_class];
1026 return sysfs_emit(buf, fmt: "%s\n", str);
1027}
1028
1029static DEVICE_ATTR_RO(pcm_class);
1030static struct attribute *pcm_dev_attrs[] = {
1031 &dev_attr_pcm_class.attr,
1032 NULL
1033};
1034
1035static const struct attribute_group pcm_dev_attr_group = {
1036 .attrs = pcm_dev_attrs,
1037};
1038
1039static const struct attribute_group *pcm_dev_attr_groups[] = {
1040 &pcm_dev_attr_group,
1041 NULL
1042};
1043
1044static int snd_pcm_dev_register(struct snd_device *device)
1045{
1046 int cidx, err;
1047 struct snd_pcm_substream *substream;
1048 struct snd_pcm *pcm;
1049
1050 if (snd_BUG_ON(!device || !device->device_data))
1051 return -ENXIO;
1052 pcm = device->device_data;
1053
1054 guard(mutex)(T: &register_mutex);
1055 err = snd_pcm_add(newpcm: pcm);
1056 if (err)
1057 return err;
1058 for (cidx = 0; cidx < 2; cidx++) {
1059 int devtype = -1;
1060 if (pcm->streams[cidx].substream == NULL)
1061 continue;
1062 switch (cidx) {
1063 case SNDRV_PCM_STREAM_PLAYBACK:
1064 devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1065 break;
1066 case SNDRV_PCM_STREAM_CAPTURE:
1067 devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1068 break;
1069 }
1070 /* register pcm */
1071 err = snd_register_device(type: devtype, card: pcm->card, dev: pcm->device,
1072 f_ops: &snd_pcm_f_ops[cidx], private_data: pcm,
1073 device: pcm->streams[cidx].dev);
1074 if (err < 0) {
1075 list_del_init(entry: &pcm->list);
1076 return err;
1077 }
1078
1079 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1080 snd_pcm_timer_init(substream);
1081 }
1082
1083 pcm_call_notify(pcm, n_register);
1084 return err;
1085}
1086
1087static int snd_pcm_dev_disconnect(struct snd_device *device)
1088{
1089 struct snd_pcm *pcm = device->device_data;
1090 struct snd_pcm_substream *substream;
1091 int cidx;
1092
1093 guard(mutex)(T: &register_mutex);
1094 guard(mutex)(T: &pcm->open_mutex);
1095 wake_up(&pcm->open_wait);
1096 list_del_init(entry: &pcm->list);
1097
1098 for_each_pcm_substream(pcm, cidx, substream) {
1099 snd_pcm_stream_lock_irq(substream);
1100 if (substream->runtime) {
1101 if (snd_pcm_running(substream))
1102 snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
1103 /* to be sure, set the state unconditionally */
1104 __snd_pcm_set_state(runtime: substream->runtime,
1105 SNDRV_PCM_STATE_DISCONNECTED);
1106 wake_up(&substream->runtime->sleep);
1107 wake_up(&substream->runtime->tsleep);
1108 }
1109 snd_pcm_stream_unlock_irq(substream);
1110 }
1111
1112 for_each_pcm_substream(pcm, cidx, substream)
1113 snd_pcm_sync_stop(substream, sync_irq: false);
1114
1115 pcm_call_notify(pcm, n_disconnect);
1116 for (cidx = 0; cidx < 2; cidx++) {
1117 if (pcm->streams[cidx].dev)
1118 snd_unregister_device(dev: pcm->streams[cidx].dev);
1119 free_chmap(pstr: &pcm->streams[cidx]);
1120 }
1121 return 0;
1122}
1123
1124#if IS_ENABLED(CONFIG_SND_PCM_OSS)
1125/**
1126 * snd_pcm_notify - Add/remove the notify list
1127 * @notify: PCM notify list
1128 * @nfree: 0 = register, 1 = unregister
1129 *
1130 * This adds the given notifier to the global list so that the callback is
1131 * called for each registered PCM devices. This exists only for PCM OSS
1132 * emulation, so far.
1133 *
1134 * Return: zero if successful, or a negative error code
1135 */
1136int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1137{
1138 struct snd_pcm *pcm;
1139
1140 if (snd_BUG_ON(!notify ||
1141 !notify->n_register ||
1142 !notify->n_unregister ||
1143 !notify->n_disconnect))
1144 return -EINVAL;
1145 guard(mutex)(&register_mutex);
1146 if (nfree) {
1147 list_del(&notify->list);
1148 list_for_each_entry(pcm, &snd_pcm_devices, list)
1149 notify->n_unregister(pcm);
1150 } else {
1151 list_add_tail(&notify->list, &snd_pcm_notify_list);
1152 list_for_each_entry(pcm, &snd_pcm_devices, list)
1153 notify->n_register(pcm);
1154 }
1155 return 0;
1156}
1157EXPORT_SYMBOL(snd_pcm_notify);
1158#endif /* CONFIG_SND_PCM_OSS */
1159
1160#ifdef CONFIG_SND_PROC_FS
1161/*
1162 * Info interface
1163 */
1164
1165static void snd_pcm_proc_read(struct snd_info_entry *entry,
1166 struct snd_info_buffer *buffer)
1167{
1168 struct snd_pcm *pcm;
1169
1170 guard(mutex)(T: &register_mutex);
1171 list_for_each_entry(pcm, &snd_pcm_devices, list) {
1172 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1173 pcm->card->number, pcm->device, pcm->id, pcm->name);
1174 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1175 snd_iprintf(buffer, " : playback %i",
1176 pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1177 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1178 snd_iprintf(buffer, " : capture %i",
1179 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1180 snd_iprintf(buffer, "\n");
1181 }
1182}
1183
1184static struct snd_info_entry *snd_pcm_proc_entry;
1185
1186static void snd_pcm_proc_init(void)
1187{
1188 struct snd_info_entry *entry;
1189
1190 entry = snd_info_create_module_entry(THIS_MODULE, name: "pcm", NULL);
1191 if (entry) {
1192 snd_info_set_text_ops(entry, NULL, read: snd_pcm_proc_read);
1193 if (snd_info_register(entry) < 0) {
1194 snd_info_free_entry(entry);
1195 entry = NULL;
1196 }
1197 }
1198 snd_pcm_proc_entry = entry;
1199}
1200
1201static void snd_pcm_proc_done(void)
1202{
1203 snd_info_free_entry(entry: snd_pcm_proc_entry);
1204}
1205
1206#else /* !CONFIG_SND_PROC_FS */
1207#define snd_pcm_proc_init()
1208#define snd_pcm_proc_done()
1209#endif /* CONFIG_SND_PROC_FS */
1210
1211
1212/*
1213 * ENTRY functions
1214 */
1215
1216static int __init alsa_pcm_init(void)
1217{
1218 snd_ctl_register_ioctl(fcn: snd_pcm_control_ioctl);
1219 snd_ctl_register_ioctl_compat(fcn: snd_pcm_control_ioctl);
1220 snd_pcm_proc_init();
1221 return 0;
1222}
1223
1224static void __exit alsa_pcm_exit(void)
1225{
1226 snd_ctl_unregister_ioctl(fcn: snd_pcm_control_ioctl);
1227 snd_ctl_unregister_ioctl_compat(fcn: snd_pcm_control_ioctl);
1228 snd_pcm_proc_done();
1229}
1230
1231module_init(alsa_pcm_init)
1232module_exit(alsa_pcm_exit)
1233