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 23 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>"); 24 MODULE_DESCRIPTION("Midlevel PCM code for ALSA."); 25 MODULE_LICENSE("GPL"); 26 27 static LIST_HEAD(snd_pcm_devices); 28 static DEFINE_MUTEX(register_mutex); 29 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 30 static LIST_HEAD(snd_pcm_notify_list); 31 #endif 32 33 static int snd_pcm_free(struct snd_pcm *pcm); 34 static int snd_pcm_dev_free(struct snd_device *device); 35 static int snd_pcm_dev_register(struct snd_device *device); 36 static int snd_pcm_dev_disconnect(struct snd_device *device); 37 38 static 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 49 static 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 62 static 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(&newpcm->list, pcm->list.prev); 76 return 0; 77 } 78 } 79 list_add_tail(&newpcm->list, &snd_pcm_devices); 80 return 0; 81 } 82 83 static 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, ®ister_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)(®ister_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)(&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 151 152 static 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 */ 212 const 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 } 220 EXPORT_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 233 234 static const char * const snd_pcm_stream_names[] = { 235 STREAM(PLAYBACK), 236 STREAM(CAPTURE), 237 }; 238 239 static 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 }; 250 251 static 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 }; 258 259 static const char * const snd_pcm_subformat_names[] = { 260 SUBFORMAT(STD), 261 SUBFORMAT(MSBITS_MAX), 262 SUBFORMAT(MSBITS_20), 263 SUBFORMAT(MSBITS_24), 264 }; 265 266 static const char * const snd_pcm_tstamp_mode_names[] = { 267 TSTAMP(NONE), 268 TSTAMP(ENABLE), 269 }; 270 271 static const char *snd_pcm_stream_name(int stream) 272 { 273 return snd_pcm_stream_names[stream]; 274 } 275 276 static const char *snd_pcm_access_name(snd_pcm_access_t access) 277 { 278 return snd_pcm_access_names[(__force int)access]; 279 } 280 281 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat) 282 { 283 return snd_pcm_subformat_names[(__force int)subformat]; 284 } 285 286 static const char *snd_pcm_tstamp_mode_name(int mode) 287 { 288 return snd_pcm_tstamp_mode_names[mode]; 289 } 290 291 static 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> 298 299 static 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 327 328 static 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 } 358 359 static 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(((struct snd_pcm_str *)entry->private_data)->substream, 363 buffer); 364 } 365 366 static 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(entry->private_data, buffer); 370 } 371 372 static 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)(&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 } 406 407 static 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)(&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 } 432 433 static 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)(&substream->pcm->open_mutex); 442 runtime = substream->runtime; 443 if (!runtime) { 444 snd_iprintf(buffer, "closed\n"); 445 return; 446 } 447 memset(&status, 0, sizeof(status)); 448 err = snd_pcm_status64(substream, &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 } 466 467 #ifdef CONFIG_SND_PCM_XRUN_DEBUG 468 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry, 469 struct snd_info_buffer *buffer) 470 { 471 struct snd_pcm_substream *substream = entry->private_data; 472 473 snd_pcm_stop_xrun(substream); 474 } 475 476 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry, 477 struct snd_info_buffer *buffer) 478 { 479 struct snd_pcm_str *pstr = entry->private_data; 480 snd_iprintf(buffer, "%d\n", pstr->xrun_debug); 481 } 482 483 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry, 484 struct snd_info_buffer *buffer) 485 { 486 struct snd_pcm_str *pstr = entry->private_data; 487 char line[64]; 488 if (!snd_info_get_line(buffer, line, sizeof(line))) 489 pstr->xrun_debug = simple_strtoul(line, NULL, 10); 490 } 491 #endif 492 493 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) 494 { 495 struct snd_pcm *pcm = pstr->pcm; 496 struct snd_info_entry *entry; 497 char name[16]; 498 499 sprintf(name, "pcm%i%c", pcm->device, 500 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c'); 501 entry = snd_info_create_card_entry(pcm->card, name, 502 pcm->card->proc_root); 503 if (!entry) 504 return -ENOMEM; 505 entry->mode = S_IFDIR | 0555; 506 pstr->proc_root = entry; 507 entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root); 508 if (entry) 509 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read); 510 #ifdef CONFIG_SND_PCM_XRUN_DEBUG 511 entry = snd_info_create_card_entry(pcm->card, "xrun_debug", 512 pstr->proc_root); 513 if (entry) { 514 snd_info_set_text_ops(entry, pstr, snd_pcm_xrun_debug_read); 515 entry->c.text.write = snd_pcm_xrun_debug_write; 516 entry->mode |= 0200; 517 } 518 #endif 519 return 0; 520 } 521 522 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) 523 { 524 snd_info_free_entry(pstr->proc_root); 525 pstr->proc_root = NULL; 526 return 0; 527 } 528 529 static struct snd_info_entry * 530 create_substream_info_entry(struct snd_pcm_substream *substream, 531 const char *name, 532 void (*read)(struct snd_info_entry *, 533 struct snd_info_buffer *)) 534 { 535 struct snd_info_entry *entry; 536 537 entry = snd_info_create_card_entry(substream->pcm->card, name, 538 substream->proc_root); 539 if (entry) 540 snd_info_set_text_ops(entry, substream, read); 541 return entry; 542 } 543 544 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) 545 { 546 struct snd_info_entry *entry; 547 struct snd_card *card; 548 char name[16]; 549 550 card = substream->pcm->card; 551 552 sprintf(name, "sub%i", substream->number); 553 entry = snd_info_create_card_entry(card, name, 554 substream->pstr->proc_root); 555 if (!entry) 556 return -ENOMEM; 557 entry->mode = S_IFDIR | 0555; 558 substream->proc_root = entry; 559 560 create_substream_info_entry(substream, "info", 561 snd_pcm_substream_proc_info_read); 562 create_substream_info_entry(substream, "hw_params", 563 snd_pcm_substream_proc_hw_params_read); 564 create_substream_info_entry(substream, "sw_params", 565 snd_pcm_substream_proc_sw_params_read); 566 create_substream_info_entry(substream, "status", 567 snd_pcm_substream_proc_status_read); 568 569 #ifdef CONFIG_SND_PCM_XRUN_DEBUG 570 entry = create_substream_info_entry(substream, "xrun_injection", NULL); 571 if (entry) { 572 entry->c.text.write = snd_pcm_xrun_injection_write; 573 entry->mode = S_IFREG | 0200; 574 } 575 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */ 576 577 return 0; 578 } 579 580 #else /* !CONFIG_SND_VERBOSE_PROCFS */ 581 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; } 582 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; } 583 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; } 584 #endif /* CONFIG_SND_VERBOSE_PROCFS */ 585 586 static const struct attribute_group *pcm_dev_attr_groups[]; 587 588 /* 589 * PM callbacks: we need to deal only with suspend here, as the resume is 590 * triggered either from user-space or the driver's resume callback 591 */ 592 #ifdef CONFIG_PM_SLEEP 593 static int do_pcm_suspend(struct device *dev) 594 { 595 struct snd_pcm_str *pstr = dev_get_drvdata(dev); 596 597 if (!pstr->pcm->no_device_suspend) 598 snd_pcm_suspend_all(pstr->pcm); 599 return 0; 600 } 601 #endif 602 603 static const struct dev_pm_ops pcm_dev_pm_ops = { 604 SET_SYSTEM_SLEEP_PM_OPS(do_pcm_suspend, NULL) 605 }; 606 607 /* device type for PCM -- basically only for passing PM callbacks */ 608 static const struct device_type pcm_dev_type = { 609 .name = "pcm", 610 .pm = &pcm_dev_pm_ops, 611 }; 612 613 /** 614 * snd_pcm_new_stream - create a new PCM stream 615 * @pcm: the pcm instance 616 * @stream: the stream direction, SNDRV_PCM_STREAM_XXX 617 * @substream_count: the number of substreams 618 * 619 * Creates a new stream for the pcm. 620 * The corresponding stream on the pcm must have been empty before 621 * calling this, i.e. zero must be given to the argument of 622 * snd_pcm_new(). 623 * 624 * Return: Zero if successful, or a negative error code on failure. 625 */ 626 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count) 627 { 628 int idx, err; 629 struct snd_pcm_str *pstr = &pcm->streams[stream]; 630 struct snd_pcm_substream *substream, *prev; 631 632 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 633 mutex_init(&pstr->oss.setup_mutex); 634 #endif 635 pstr->stream = stream; 636 pstr->pcm = pcm; 637 pstr->substream_count = substream_count; 638 if (!substream_count) 639 return 0; 640 641 err = snd_device_alloc(&pstr->dev, pcm->card); 642 if (err < 0) 643 return err; 644 dev_set_name(pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device, 645 stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c'); 646 pstr->dev->groups = pcm_dev_attr_groups; 647 pstr->dev->type = &pcm_dev_type; 648 dev_set_drvdata(pstr->dev, pstr); 649 650 if (!pcm->internal) { 651 err = snd_pcm_stream_proc_init(pstr); 652 if (err < 0) { 653 pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n"); 654 return err; 655 } 656 } 657 prev = NULL; 658 for (idx = 0, prev = NULL; idx < substream_count; idx++) { 659 substream = kzalloc(sizeof(*substream), GFP_KERNEL); 660 if (!substream) 661 return -ENOMEM; 662 substream->pcm = pcm; 663 substream->pstr = pstr; 664 substream->number = idx; 665 substream->stream = stream; 666 sprintf(substream->name, "subdevice #%i", idx); 667 substream->buffer_bytes_max = UINT_MAX; 668 if (prev == NULL) 669 pstr->substream = substream; 670 else 671 prev->next = substream; 672 673 if (!pcm->internal) { 674 err = snd_pcm_substream_proc_init(substream); 675 if (err < 0) { 676 pcm_err(pcm, 677 "Error in snd_pcm_stream_proc_init\n"); 678 if (prev == NULL) 679 pstr->substream = NULL; 680 else 681 prev->next = NULL; 682 kfree(substream); 683 return err; 684 } 685 } 686 substream->group = &substream->self_group; 687 snd_pcm_group_init(&substream->self_group); 688 list_add_tail(&substream->link_list, &substream->self_group.substreams); 689 atomic_set(&substream->mmap_count, 0); 690 prev = substream; 691 } 692 return 0; 693 } 694 EXPORT_SYMBOL(snd_pcm_new_stream); 695 696 static int _snd_pcm_new(struct snd_card *card, const char *id, int device, 697 int playback_count, int capture_count, bool internal, 698 struct snd_pcm **rpcm) 699 { 700 struct snd_pcm *pcm; 701 int err; 702 static const struct snd_device_ops ops = { 703 .dev_free = snd_pcm_dev_free, 704 .dev_register = snd_pcm_dev_register, 705 .dev_disconnect = snd_pcm_dev_disconnect, 706 }; 707 static const struct snd_device_ops internal_ops = { 708 .dev_free = snd_pcm_dev_free, 709 }; 710 711 if (snd_BUG_ON(!card)) 712 return -ENXIO; 713 if (rpcm) 714 *rpcm = NULL; 715 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL); 716 if (!pcm) 717 return -ENOMEM; 718 pcm->card = card; 719 pcm->device = device; 720 pcm->internal = internal; 721 mutex_init(&pcm->open_mutex); 722 init_waitqueue_head(&pcm->open_wait); 723 INIT_LIST_HEAD(&pcm->list); 724 if (id) 725 strscpy(pcm->id, id, sizeof(pcm->id)); 726 727 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, 728 playback_count); 729 if (err < 0) 730 goto free_pcm; 731 732 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count); 733 if (err < 0) 734 goto free_pcm; 735 736 err = snd_device_new(card, SNDRV_DEV_PCM, pcm, 737 internal ? &internal_ops : &ops); 738 if (err < 0) 739 goto free_pcm; 740 741 if (rpcm) 742 *rpcm = pcm; 743 return 0; 744 745 free_pcm: 746 snd_pcm_free(pcm); 747 return err; 748 } 749 750 /** 751 * snd_pcm_new - create a new PCM instance 752 * @card: the card instance 753 * @id: the id string 754 * @device: the device index (zero based) 755 * @playback_count: the number of substreams for playback 756 * @capture_count: the number of substreams for capture 757 * @rpcm: the pointer to store the new pcm instance 758 * 759 * Creates a new PCM instance. 760 * 761 * The pcm operators have to be set afterwards to the new instance 762 * via snd_pcm_set_ops(). 763 * 764 * Return: Zero if successful, or a negative error code on failure. 765 */ 766 int snd_pcm_new(struct snd_card *card, const char *id, int device, 767 int playback_count, int capture_count, struct snd_pcm **rpcm) 768 { 769 return _snd_pcm_new(card, id, device, playback_count, capture_count, 770 false, rpcm); 771 } 772 EXPORT_SYMBOL(snd_pcm_new); 773 774 /** 775 * snd_pcm_new_internal - create a new internal PCM instance 776 * @card: the card instance 777 * @id: the id string 778 * @device: the device index (zero based - shared with normal PCMs) 779 * @playback_count: the number of substreams for playback 780 * @capture_count: the number of substreams for capture 781 * @rpcm: the pointer to store the new pcm instance 782 * 783 * Creates a new internal PCM instance with no userspace device or procfs 784 * entries. This is used by ASoC Back End PCMs in order to create a PCM that 785 * will only be used internally by kernel drivers. i.e. it cannot be opened 786 * by userspace. It provides existing ASoC components drivers with a substream 787 * and access to any private data. 788 * 789 * The pcm operators have to be set afterwards to the new instance 790 * via snd_pcm_set_ops(). 791 * 792 * Return: Zero if successful, or a negative error code on failure. 793 */ 794 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device, 795 int playback_count, int capture_count, 796 struct snd_pcm **rpcm) 797 { 798 return _snd_pcm_new(card, id, device, playback_count, capture_count, 799 true, rpcm); 800 } 801 EXPORT_SYMBOL(snd_pcm_new_internal); 802 803 static void free_chmap(struct snd_pcm_str *pstr) 804 { 805 if (pstr->chmap_kctl) { 806 struct snd_card *card = pstr->pcm->card; 807 808 snd_ctl_remove(card, pstr->chmap_kctl); 809 pstr->chmap_kctl = NULL; 810 } 811 } 812 813 static void snd_pcm_free_stream(struct snd_pcm_str * pstr) 814 { 815 struct snd_pcm_substream *substream, *substream_next; 816 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 817 struct snd_pcm_oss_setup *setup, *setupn; 818 #endif 819 820 /* free all proc files under the stream */ 821 snd_pcm_stream_proc_done(pstr); 822 823 substream = pstr->substream; 824 while (substream) { 825 substream_next = substream->next; 826 snd_pcm_timer_done(substream); 827 kfree(substream); 828 substream = substream_next; 829 } 830 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 831 for (setup = pstr->oss.setup_list; setup; setup = setupn) { 832 setupn = setup->next; 833 kfree(setup->task_name); 834 kfree(setup); 835 } 836 #endif 837 free_chmap(pstr); 838 if (pstr->substream_count) 839 put_device(pstr->dev); 840 } 841 842 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 843 #define pcm_call_notify(pcm, call) \ 844 do { \ 845 struct snd_pcm_notify *_notify; \ 846 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \ 847 _notify->call(pcm); \ 848 } while (0) 849 #else 850 #define pcm_call_notify(pcm, call) do {} while (0) 851 #endif 852 853 static int snd_pcm_free(struct snd_pcm *pcm) 854 { 855 if (!pcm) 856 return 0; 857 if (!pcm->internal) 858 pcm_call_notify(pcm, n_unregister); 859 if (pcm->private_free) 860 pcm->private_free(pcm); 861 snd_pcm_lib_preallocate_free_for_all(pcm); 862 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]); 863 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]); 864 kfree(pcm); 865 return 0; 866 } 867 868 static int snd_pcm_dev_free(struct snd_device *device) 869 { 870 struct snd_pcm *pcm = device->device_data; 871 return snd_pcm_free(pcm); 872 } 873 874 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream, 875 struct file *file, 876 struct snd_pcm_substream **rsubstream) 877 { 878 struct snd_pcm_str * pstr; 879 struct snd_pcm_substream *substream; 880 struct snd_pcm_runtime *runtime; 881 struct snd_card *card; 882 int prefer_subdevice; 883 size_t size; 884 885 if (snd_BUG_ON(!pcm || !rsubstream)) 886 return -ENXIO; 887 if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK && 888 stream != SNDRV_PCM_STREAM_CAPTURE)) 889 return -EINVAL; 890 *rsubstream = NULL; 891 pstr = &pcm->streams[stream]; 892 if (pstr->substream == NULL || pstr->substream_count == 0) 893 return -ENODEV; 894 895 card = pcm->card; 896 prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM); 897 898 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) { 899 int opposite = !stream; 900 901 for (substream = pcm->streams[opposite].substream; substream; 902 substream = substream->next) { 903 if (SUBSTREAM_BUSY(substream)) 904 return -EAGAIN; 905 } 906 } 907 908 if (file->f_flags & O_APPEND) { 909 if (prefer_subdevice < 0) { 910 if (pstr->substream_count > 1) 911 return -EINVAL; /* must be unique */ 912 substream = pstr->substream; 913 } else { 914 for (substream = pstr->substream; substream; 915 substream = substream->next) 916 if (substream->number == prefer_subdevice) 917 break; 918 } 919 if (! substream) 920 return -ENODEV; 921 if (! SUBSTREAM_BUSY(substream)) 922 return -EBADFD; 923 substream->ref_count++; 924 *rsubstream = substream; 925 return 0; 926 } 927 928 for (substream = pstr->substream; substream; substream = substream->next) { 929 if (!SUBSTREAM_BUSY(substream) && 930 (prefer_subdevice == -1 || 931 substream->number == prefer_subdevice)) 932 break; 933 } 934 if (substream == NULL) 935 return -EAGAIN; 936 937 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL); 938 if (runtime == NULL) 939 return -ENOMEM; 940 941 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)); 942 runtime->status = alloc_pages_exact(size, GFP_KERNEL); 943 if (runtime->status == NULL) { 944 kfree(runtime); 945 return -ENOMEM; 946 } 947 memset(runtime->status, 0, size); 948 949 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)); 950 runtime->control = alloc_pages_exact(size, GFP_KERNEL); 951 if (runtime->control == NULL) { 952 free_pages_exact(runtime->status, 953 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status))); 954 kfree(runtime); 955 return -ENOMEM; 956 } 957 memset(runtime->control, 0, size); 958 959 init_waitqueue_head(&runtime->sleep); 960 init_waitqueue_head(&runtime->tsleep); 961 962 __snd_pcm_set_state(runtime, SNDRV_PCM_STATE_OPEN); 963 mutex_init(&runtime->buffer_mutex); 964 atomic_set(&runtime->buffer_accessing, 0); 965 966 substream->runtime = runtime; 967 substream->private_data = pcm->private_data; 968 substream->ref_count = 1; 969 substream->f_flags = file->f_flags; 970 substream->pid = get_pid(task_pid(current)); 971 pstr->substream_opened++; 972 *rsubstream = substream; 973 return 0; 974 } 975 976 void snd_pcm_detach_substream(struct snd_pcm_substream *substream) 977 { 978 struct snd_pcm_runtime *runtime; 979 980 if (PCM_RUNTIME_CHECK(substream)) 981 return; 982 runtime = substream->runtime; 983 if (runtime->private_free != NULL) 984 runtime->private_free(runtime); 985 free_pages_exact(runtime->status, 986 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status))); 987 free_pages_exact(runtime->control, 988 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control))); 989 kfree(runtime->hw_constraints.rules); 990 /* Avoid concurrent access to runtime via PCM timer interface */ 991 if (substream->timer) { 992 scoped_guard(spinlock_irq, &substream->timer->lock) 993 substream->runtime = NULL; 994 } else { 995 substream->runtime = NULL; 996 } 997 mutex_destroy(&runtime->buffer_mutex); 998 snd_fasync_free(runtime->fasync); 999 kfree(runtime); 1000 put_pid(substream->pid); 1001 substream->pid = NULL; 1002 substream->pstr->substream_opened--; 1003 } 1004 1005 static ssize_t pcm_class_show(struct device *dev, 1006 struct device_attribute *attr, char *buf) 1007 { 1008 struct snd_pcm_str *pstr = dev_get_drvdata(dev); 1009 struct snd_pcm *pcm = pstr->pcm; 1010 const char *str; 1011 static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = { 1012 [SNDRV_PCM_CLASS_GENERIC] = "generic", 1013 [SNDRV_PCM_CLASS_MULTI] = "multi", 1014 [SNDRV_PCM_CLASS_MODEM] = "modem", 1015 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer", 1016 }; 1017 1018 if (pcm->dev_class > SNDRV_PCM_CLASS_LAST) 1019 str = "none"; 1020 else 1021 str = strs[pcm->dev_class]; 1022 return sysfs_emit(buf, "%s\n", str); 1023 } 1024 1025 static DEVICE_ATTR_RO(pcm_class); 1026 static struct attribute *pcm_dev_attrs[] = { 1027 &dev_attr_pcm_class.attr, 1028 NULL 1029 }; 1030 1031 static const struct attribute_group pcm_dev_attr_group = { 1032 .attrs = pcm_dev_attrs, 1033 }; 1034 1035 static const struct attribute_group *pcm_dev_attr_groups[] = { 1036 &pcm_dev_attr_group, 1037 NULL 1038 }; 1039 1040 static int snd_pcm_dev_register(struct snd_device *device) 1041 { 1042 int cidx, err; 1043 struct snd_pcm_substream *substream; 1044 struct snd_pcm *pcm; 1045 1046 if (snd_BUG_ON(!device || !device->device_data)) 1047 return -ENXIO; 1048 pcm = device->device_data; 1049 1050 guard(mutex)(®ister_mutex); 1051 err = snd_pcm_add(pcm); 1052 if (err) 1053 return err; 1054 for (cidx = 0; cidx < 2; cidx++) { 1055 int devtype = -1; 1056 if (pcm->streams[cidx].substream == NULL) 1057 continue; 1058 switch (cidx) { 1059 case SNDRV_PCM_STREAM_PLAYBACK: 1060 devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK; 1061 break; 1062 case SNDRV_PCM_STREAM_CAPTURE: 1063 devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE; 1064 break; 1065 } 1066 /* register pcm */ 1067 err = snd_register_device(devtype, pcm->card, pcm->device, 1068 &snd_pcm_f_ops[cidx], pcm, 1069 pcm->streams[cidx].dev); 1070 if (err < 0) { 1071 list_del_init(&pcm->list); 1072 return err; 1073 } 1074 1075 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) 1076 snd_pcm_timer_init(substream); 1077 } 1078 1079 pcm_call_notify(pcm, n_register); 1080 return err; 1081 } 1082 1083 static int snd_pcm_dev_disconnect(struct snd_device *device) 1084 { 1085 struct snd_pcm *pcm = device->device_data; 1086 struct snd_pcm_substream *substream; 1087 int cidx; 1088 1089 guard(mutex)(®ister_mutex); 1090 guard(mutex)(&pcm->open_mutex); 1091 wake_up(&pcm->open_wait); 1092 list_del_init(&pcm->list); 1093 1094 for_each_pcm_substream(pcm, cidx, substream) { 1095 snd_pcm_stream_lock_irq(substream); 1096 if (substream->runtime) { 1097 if (snd_pcm_running(substream)) 1098 snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED); 1099 /* to be sure, set the state unconditionally */ 1100 __snd_pcm_set_state(substream->runtime, 1101 SNDRV_PCM_STATE_DISCONNECTED); 1102 wake_up(&substream->runtime->sleep); 1103 wake_up(&substream->runtime->tsleep); 1104 } 1105 snd_pcm_stream_unlock_irq(substream); 1106 } 1107 1108 for_each_pcm_substream(pcm, cidx, substream) 1109 snd_pcm_sync_stop(substream, false); 1110 1111 pcm_call_notify(pcm, n_disconnect); 1112 for (cidx = 0; cidx < 2; cidx++) { 1113 if (pcm->streams[cidx].dev) 1114 snd_unregister_device(pcm->streams[cidx].dev); 1115 free_chmap(&pcm->streams[cidx]); 1116 } 1117 return 0; 1118 } 1119 1120 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 1121 /** 1122 * snd_pcm_notify - Add/remove the notify list 1123 * @notify: PCM notify list 1124 * @nfree: 0 = register, 1 = unregister 1125 * 1126 * This adds the given notifier to the global list so that the callback is 1127 * called for each registered PCM devices. This exists only for PCM OSS 1128 * emulation, so far. 1129 * 1130 * Return: zero if successful, or a negative error code 1131 */ 1132 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree) 1133 { 1134 struct snd_pcm *pcm; 1135 1136 if (snd_BUG_ON(!notify || 1137 !notify->n_register || 1138 !notify->n_unregister || 1139 !notify->n_disconnect)) 1140 return -EINVAL; 1141 guard(mutex)(®ister_mutex); 1142 if (nfree) { 1143 list_del(¬ify->list); 1144 list_for_each_entry(pcm, &snd_pcm_devices, list) 1145 notify->n_unregister(pcm); 1146 } else { 1147 list_add_tail(¬ify->list, &snd_pcm_notify_list); 1148 list_for_each_entry(pcm, &snd_pcm_devices, list) 1149 notify->n_register(pcm); 1150 } 1151 return 0; 1152 } 1153 EXPORT_SYMBOL(snd_pcm_notify); 1154 #endif /* CONFIG_SND_PCM_OSS */ 1155 1156 #ifdef CONFIG_SND_PROC_FS 1157 /* 1158 * Info interface 1159 */ 1160 1161 static void snd_pcm_proc_read(struct snd_info_entry *entry, 1162 struct snd_info_buffer *buffer) 1163 { 1164 struct snd_pcm *pcm; 1165 1166 guard(mutex)(®ister_mutex); 1167 list_for_each_entry(pcm, &snd_pcm_devices, list) { 1168 snd_iprintf(buffer, "%02i-%02i: %s : %s", 1169 pcm->card->number, pcm->device, pcm->id, pcm->name); 1170 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) 1171 snd_iprintf(buffer, " : playback %i", 1172 pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count); 1173 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) 1174 snd_iprintf(buffer, " : capture %i", 1175 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count); 1176 snd_iprintf(buffer, "\n"); 1177 } 1178 } 1179 1180 static struct snd_info_entry *snd_pcm_proc_entry; 1181 1182 static void snd_pcm_proc_init(void) 1183 { 1184 struct snd_info_entry *entry; 1185 1186 entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL); 1187 if (entry) { 1188 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read); 1189 if (snd_info_register(entry) < 0) { 1190 snd_info_free_entry(entry); 1191 entry = NULL; 1192 } 1193 } 1194 snd_pcm_proc_entry = entry; 1195 } 1196 1197 static void snd_pcm_proc_done(void) 1198 { 1199 snd_info_free_entry(snd_pcm_proc_entry); 1200 } 1201 1202 #else /* !CONFIG_SND_PROC_FS */ 1203 #define snd_pcm_proc_init() 1204 #define snd_pcm_proc_done() 1205 #endif /* CONFIG_SND_PROC_FS */ 1206 1207 1208 /* 1209 * ENTRY functions 1210 */ 1211 1212 static int __init alsa_pcm_init(void) 1213 { 1214 snd_ctl_register_ioctl(snd_pcm_control_ioctl); 1215 snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl); 1216 snd_pcm_proc_init(); 1217 return 0; 1218 } 1219 1220 static void __exit alsa_pcm_exit(void) 1221 { 1222 snd_ctl_unregister_ioctl(snd_pcm_control_ioctl); 1223 snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl); 1224 snd_pcm_proc_done(); 1225 } 1226 1227 module_init(alsa_pcm_init) 1228 module_exit(alsa_pcm_exit) 1229