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 #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 471 static 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 } 478 479 static 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 } 485 486 static 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 495 496 static 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(name, "pcm%i%c", pcm->device, 503 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c'); 504 entry = snd_info_create_card_entry(pcm->card, name, 505 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(pcm->card, "info", pstr->proc_root); 511 if (entry) 512 snd_info_set_text_ops(entry, pstr, 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 } 524 525 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) 526 { 527 snd_info_free_entry(pstr->proc_root); 528 pstr->proc_root = NULL; 529 return 0; 530 } 531 532 static struct snd_info_entry * 533 create_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(substream->pcm->card, name, 541 substream->proc_root); 542 if (entry) 543 snd_info_set_text_ops(entry, substream, read); 544 return entry; 545 } 546 547 static 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(name, "sub%i", substream->number); 556 entry = snd_info_create_card_entry(card, name, 557 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, "info", 564 snd_pcm_substream_proc_info_read); 565 create_substream_info_entry(substream, "hw_params", 566 snd_pcm_substream_proc_hw_params_read); 567 create_substream_info_entry(substream, "sw_params", 568 snd_pcm_substream_proc_sw_params_read); 569 create_substream_info_entry(substream, "status", 570 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 */ 584 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; } 585 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; } 586 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; } 587 #endif /* CONFIG_SND_VERBOSE_PROCFS */ 588 589 static 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 */ 595 #ifdef CONFIG_PM_SLEEP 596 static int do_pcm_suspend(struct device *dev) 597 { 598 struct snd_pcm_str *pstr = dev_get_drvdata(dev); 599 600 if (!pstr->pcm->no_device_suspend) 601 snd_pcm_suspend_all(pstr->pcm); 602 return 0; 603 } 604 #endif 605 606 static const struct dev_pm_ops pcm_dev_pm_ops = { 607 SET_SYSTEM_SLEEP_PM_OPS(do_pcm_suspend, NULL) 608 }; 609 610 /* device type for PCM -- basically only for passing PM callbacks */ 611 static const struct device_type pcm_dev_type = { 612 .name = "pcm", 613 .pm = &pcm_dev_pm_ops, 614 }; 615 616 /** 617 * snd_pcm_new_stream - create a new PCM stream 618 * @pcm: the pcm instance 619 * @stream: the stream direction, SNDRV_PCM_STREAM_XXX 620 * @substream_count: the number of substreams 621 * 622 * Creates a new stream for the pcm. 623 * The corresponding stream on the pcm must have been empty before 624 * calling this, i.e. zero must be given to the argument of 625 * snd_pcm_new(). 626 * 627 * Return: Zero if successful, or a negative error code on failure. 628 */ 629 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count) 630 { 631 int idx, err; 632 struct snd_pcm_str *pstr = &pcm->streams[stream]; 633 struct snd_pcm_substream *substream, *prev; 634 635 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 636 mutex_init(&pstr->oss.setup_mutex); 637 #endif 638 pstr->stream = stream; 639 pstr->pcm = pcm; 640 pstr->substream_count = substream_count; 641 if (!substream_count) 642 return 0; 643 644 err = snd_device_alloc(&pstr->dev, pcm->card); 645 if (err < 0) 646 return err; 647 dev_set_name(pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device, 648 stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c'); 649 pstr->dev->groups = pcm_dev_attr_groups; 650 pstr->dev->type = &pcm_dev_type; 651 dev_set_drvdata(pstr->dev, pstr); 652 653 if (!pcm->internal) { 654 err = snd_pcm_stream_proc_init(pstr); 655 if (err < 0) { 656 pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n"); 657 return err; 658 } 659 } 660 prev = NULL; 661 for (idx = 0, prev = NULL; idx < substream_count; idx++) { 662 substream = kzalloc(sizeof(*substream), GFP_KERNEL); 663 if (!substream) 664 return -ENOMEM; 665 substream->pcm = pcm; 666 substream->pstr = pstr; 667 substream->number = idx; 668 substream->stream = stream; 669 sprintf(substream->name, "subdevice #%i", idx); 670 substream->buffer_bytes_max = UINT_MAX; 671 if (prev == NULL) 672 pstr->substream = substream; 673 else 674 prev->next = substream; 675 676 if (!pcm->internal) { 677 err = snd_pcm_substream_proc_init(substream); 678 if (err < 0) { 679 pcm_err(pcm, 680 "Error in snd_pcm_stream_proc_init\n"); 681 if (prev == NULL) 682 pstr->substream = NULL; 683 else 684 prev->next = NULL; 685 kfree(substream); 686 return err; 687 } 688 } 689 substream->group = &substream->self_group; 690 snd_pcm_group_init(&substream->self_group); 691 list_add_tail(&substream->link_list, &substream->self_group.substreams); 692 atomic_set(&substream->mmap_count, 0); 693 prev = substream; 694 } 695 return 0; 696 } 697 EXPORT_SYMBOL(snd_pcm_new_stream); 698 699 static int _snd_pcm_new(struct snd_card *card, const char *id, int device, 700 int playback_count, int capture_count, bool internal, 701 struct snd_pcm **rpcm) 702 { 703 struct snd_pcm *pcm; 704 int err; 705 static const struct snd_device_ops ops = { 706 .dev_free = snd_pcm_dev_free, 707 .dev_register = snd_pcm_dev_register, 708 .dev_disconnect = snd_pcm_dev_disconnect, 709 }; 710 static const struct snd_device_ops internal_ops = { 711 .dev_free = snd_pcm_dev_free, 712 }; 713 714 if (snd_BUG_ON(!card)) 715 return -ENXIO; 716 if (rpcm) 717 *rpcm = NULL; 718 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL); 719 if (!pcm) 720 return -ENOMEM; 721 pcm->card = card; 722 pcm->device = device; 723 pcm->internal = internal; 724 mutex_init(&pcm->open_mutex); 725 init_waitqueue_head(&pcm->open_wait); 726 INIT_LIST_HEAD(&pcm->list); 727 if (id) 728 strscpy(pcm->id, id, sizeof(pcm->id)); 729 730 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, 731 playback_count); 732 if (err < 0) 733 goto free_pcm; 734 735 err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count); 736 if (err < 0) 737 goto free_pcm; 738 739 err = snd_device_new(card, SNDRV_DEV_PCM, pcm, 740 internal ? &internal_ops : &ops); 741 if (err < 0) 742 goto free_pcm; 743 744 if (rpcm) 745 *rpcm = pcm; 746 return 0; 747 748 free_pcm: 749 snd_pcm_free(pcm); 750 return err; 751 } 752 753 /** 754 * snd_pcm_new - create a new PCM instance 755 * @card: the card instance 756 * @id: the id string 757 * @device: the device index (zero based) 758 * @playback_count: the number of substreams for playback 759 * @capture_count: the number of substreams for capture 760 * @rpcm: the pointer to store the new pcm instance 761 * 762 * Creates a new PCM instance. 763 * 764 * The pcm operators have to be set afterwards to the new instance 765 * via snd_pcm_set_ops(). 766 * 767 * Return: Zero if successful, or a negative error code on failure. 768 */ 769 int snd_pcm_new(struct snd_card *card, const char *id, int device, 770 int playback_count, int capture_count, struct snd_pcm **rpcm) 771 { 772 return _snd_pcm_new(card, id, device, playback_count, capture_count, 773 false, rpcm); 774 } 775 EXPORT_SYMBOL(snd_pcm_new); 776 777 /** 778 * snd_pcm_new_internal - create a new internal PCM instance 779 * @card: the card instance 780 * @id: the id string 781 * @device: the device index (zero based - shared with normal PCMs) 782 * @playback_count: the number of substreams for playback 783 * @capture_count: the number of substreams for capture 784 * @rpcm: the pointer to store the new pcm instance 785 * 786 * Creates a new internal PCM instance with no userspace device or procfs 787 * entries. This is used by ASoC Back End PCMs in order to create a PCM that 788 * will only be used internally by kernel drivers. i.e. it cannot be opened 789 * by userspace. It provides existing ASoC components drivers with a substream 790 * and access to any private data. 791 * 792 * The pcm operators have to be set afterwards to the new instance 793 * via snd_pcm_set_ops(). 794 * 795 * Return: Zero if successful, or a negative error code on failure. 796 */ 797 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device, 798 int playback_count, int capture_count, 799 struct snd_pcm **rpcm) 800 { 801 return _snd_pcm_new(card, id, device, playback_count, capture_count, 802 true, rpcm); 803 } 804 EXPORT_SYMBOL(snd_pcm_new_internal); 805 806 static void free_chmap(struct snd_pcm_str *pstr) 807 { 808 if (pstr->chmap_kctl) { 809 struct snd_card *card = pstr->pcm->card; 810 811 snd_ctl_remove(card, pstr->chmap_kctl); 812 pstr->chmap_kctl = NULL; 813 } 814 } 815 816 static void snd_pcm_free_stream(struct snd_pcm_str * pstr) 817 { 818 struct snd_pcm_substream *substream, *substream_next; 819 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 820 struct snd_pcm_oss_setup *setup, *setupn; 821 #endif 822 823 /* free all proc files under the stream */ 824 snd_pcm_stream_proc_done(pstr); 825 826 substream = pstr->substream; 827 while (substream) { 828 substream_next = substream->next; 829 snd_pcm_timer_done(substream); 830 kfree(substream); 831 substream = substream_next; 832 } 833 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 834 for (setup = pstr->oss.setup_list; setup; setup = setupn) { 835 setupn = setup->next; 836 kfree(setup->task_name); 837 kfree(setup); 838 } 839 #endif 840 free_chmap(pstr); 841 if (pstr->substream_count) 842 put_device(pstr->dev); 843 } 844 845 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 846 #define pcm_call_notify(pcm, call) \ 847 do { \ 848 struct snd_pcm_notify *_notify; \ 849 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \ 850 _notify->call(pcm); \ 851 } while (0) 852 #else 853 #define pcm_call_notify(pcm, call) do {} while (0) 854 #endif 855 856 static int snd_pcm_free(struct snd_pcm *pcm) 857 { 858 if (!pcm) 859 return 0; 860 if (!pcm->internal) 861 pcm_call_notify(pcm, n_unregister); 862 if (pcm->private_free) 863 pcm->private_free(pcm); 864 snd_pcm_lib_preallocate_free_for_all(pcm); 865 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]); 866 snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]); 867 kfree(pcm); 868 return 0; 869 } 870 871 static int snd_pcm_dev_free(struct snd_device *device) 872 { 873 struct snd_pcm *pcm = device->device_data; 874 return snd_pcm_free(pcm); 875 } 876 877 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream, 878 struct file *file, 879 struct snd_pcm_substream **rsubstream) 880 { 881 struct snd_pcm_str * pstr; 882 struct snd_pcm_substream *substream; 883 struct snd_pcm_runtime *runtime; 884 struct snd_card *card; 885 int prefer_subdevice; 886 size_t size; 887 888 if (snd_BUG_ON(!pcm || !rsubstream)) 889 return -ENXIO; 890 if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK && 891 stream != SNDRV_PCM_STREAM_CAPTURE)) 892 return -EINVAL; 893 *rsubstream = NULL; 894 pstr = &pcm->streams[stream]; 895 if (pstr->substream == NULL || pstr->substream_count == 0) 896 return -ENODEV; 897 898 card = pcm->card; 899 prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM); 900 901 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) { 902 int opposite = !stream; 903 904 for (substream = pcm->streams[opposite].substream; substream; 905 substream = substream->next) { 906 if (SUBSTREAM_BUSY(substream)) 907 return -EAGAIN; 908 } 909 } 910 911 if (file->f_flags & O_APPEND) { 912 if (prefer_subdevice < 0) { 913 if (pstr->substream_count > 1) 914 return -EINVAL; /* must be unique */ 915 substream = pstr->substream; 916 } else { 917 for (substream = pstr->substream; substream; 918 substream = substream->next) 919 if (substream->number == prefer_subdevice) 920 break; 921 } 922 if (! substream) 923 return -ENODEV; 924 if (! SUBSTREAM_BUSY(substream)) 925 return -EBADFD; 926 substream->ref_count++; 927 *rsubstream = substream; 928 return 0; 929 } 930 931 for (substream = pstr->substream; substream; substream = substream->next) { 932 if (!SUBSTREAM_BUSY(substream) && 933 (prefer_subdevice == -1 || 934 substream->number == prefer_subdevice)) 935 break; 936 } 937 if (substream == NULL) 938 return -EAGAIN; 939 940 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL); 941 if (runtime == NULL) 942 return -ENOMEM; 943 944 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)); 945 runtime->status = alloc_pages_exact(size, GFP_KERNEL); 946 if (runtime->status == NULL) { 947 kfree(runtime); 948 return -ENOMEM; 949 } 950 memset(runtime->status, 0, size); 951 952 size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)); 953 runtime->control = alloc_pages_exact(size, GFP_KERNEL); 954 if (runtime->control == NULL) { 955 free_pages_exact(runtime->status, 956 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status))); 957 kfree(runtime); 958 return -ENOMEM; 959 } 960 memset(runtime->control, 0, size); 961 962 init_waitqueue_head(&runtime->sleep); 963 init_waitqueue_head(&runtime->tsleep); 964 965 __snd_pcm_set_state(runtime, SNDRV_PCM_STATE_OPEN); 966 mutex_init(&runtime->buffer_mutex); 967 atomic_set(&runtime->buffer_accessing, 0); 968 969 substream->runtime = runtime; 970 substream->private_data = pcm->private_data; 971 substream->ref_count = 1; 972 substream->f_flags = file->f_flags; 973 substream->pid = get_pid(task_pid(current)); 974 pstr->substream_opened++; 975 *rsubstream = substream; 976 #ifdef CONFIG_SND_PCM_XRUN_DEBUG 977 substream->xrun_counter = 0; 978 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */ 979 return 0; 980 } 981 982 void snd_pcm_detach_substream(struct snd_pcm_substream *substream) 983 { 984 struct snd_pcm_runtime *runtime; 985 986 if (PCM_RUNTIME_CHECK(substream)) 987 return; 988 runtime = substream->runtime; 989 if (runtime->private_free != NULL) 990 runtime->private_free(runtime); 991 free_pages_exact(runtime->status, 992 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status))); 993 free_pages_exact(runtime->control, 994 PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control))); 995 kfree(runtime->hw_constraints.rules); 996 /* Avoid concurrent access to runtime via PCM timer interface */ 997 if (substream->timer) { 998 scoped_guard(spinlock_irq, &substream->timer->lock) 999 substream->runtime = NULL; 1000 } else { 1001 substream->runtime = NULL; 1002 } 1003 mutex_destroy(&runtime->buffer_mutex); 1004 snd_fasync_free(runtime->fasync); 1005 kfree(runtime); 1006 put_pid(substream->pid); 1007 substream->pid = NULL; 1008 substream->pstr->substream_opened--; 1009 } 1010 1011 static ssize_t pcm_class_show(struct device *dev, 1012 struct device_attribute *attr, char *buf) 1013 { 1014 struct snd_pcm_str *pstr = dev_get_drvdata(dev); 1015 struct snd_pcm *pcm = pstr->pcm; 1016 const char *str; 1017 static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = { 1018 [SNDRV_PCM_CLASS_GENERIC] = "generic", 1019 [SNDRV_PCM_CLASS_MULTI] = "multi", 1020 [SNDRV_PCM_CLASS_MODEM] = "modem", 1021 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer", 1022 }; 1023 1024 if (pcm->dev_class > SNDRV_PCM_CLASS_LAST) 1025 str = "none"; 1026 else 1027 str = strs[pcm->dev_class]; 1028 return sysfs_emit(buf, "%s\n", str); 1029 } 1030 1031 static DEVICE_ATTR_RO(pcm_class); 1032 static struct attribute *pcm_dev_attrs[] = { 1033 &dev_attr_pcm_class.attr, 1034 NULL 1035 }; 1036 1037 static const struct attribute_group pcm_dev_attr_group = { 1038 .attrs = pcm_dev_attrs, 1039 }; 1040 1041 static const struct attribute_group *pcm_dev_attr_groups[] = { 1042 &pcm_dev_attr_group, 1043 NULL 1044 }; 1045 1046 static int snd_pcm_dev_register(struct snd_device *device) 1047 { 1048 int cidx, err; 1049 struct snd_pcm_substream *substream; 1050 struct snd_pcm *pcm; 1051 1052 if (snd_BUG_ON(!device || !device->device_data)) 1053 return -ENXIO; 1054 pcm = device->device_data; 1055 1056 guard(mutex)(®ister_mutex); 1057 err = snd_pcm_add(pcm); 1058 if (err) 1059 return err; 1060 for (cidx = 0; cidx < 2; cidx++) { 1061 int devtype = -1; 1062 if (pcm->streams[cidx].substream == NULL) 1063 continue; 1064 switch (cidx) { 1065 case SNDRV_PCM_STREAM_PLAYBACK: 1066 devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK; 1067 break; 1068 case SNDRV_PCM_STREAM_CAPTURE: 1069 devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE; 1070 break; 1071 } 1072 /* register pcm */ 1073 err = snd_register_device(devtype, pcm->card, pcm->device, 1074 &snd_pcm_f_ops[cidx], pcm, 1075 pcm->streams[cidx].dev); 1076 if (err < 0) { 1077 list_del_init(&pcm->list); 1078 return err; 1079 } 1080 1081 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) 1082 snd_pcm_timer_init(substream); 1083 } 1084 1085 pcm_call_notify(pcm, n_register); 1086 return err; 1087 } 1088 1089 static int snd_pcm_dev_disconnect(struct snd_device *device) 1090 { 1091 struct snd_pcm *pcm = device->device_data; 1092 struct snd_pcm_substream *substream; 1093 int cidx; 1094 1095 guard(mutex)(®ister_mutex); 1096 guard(mutex)(&pcm->open_mutex); 1097 wake_up(&pcm->open_wait); 1098 list_del_init(&pcm->list); 1099 1100 for_each_pcm_substream(pcm, cidx, substream) { 1101 snd_pcm_stream_lock_irq(substream); 1102 if (substream->runtime) { 1103 if (snd_pcm_running(substream)) 1104 snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED); 1105 /* to be sure, set the state unconditionally */ 1106 __snd_pcm_set_state(substream->runtime, 1107 SNDRV_PCM_STATE_DISCONNECTED); 1108 wake_up(&substream->runtime->sleep); 1109 wake_up(&substream->runtime->tsleep); 1110 } 1111 snd_pcm_stream_unlock_irq(substream); 1112 } 1113 1114 for_each_pcm_substream(pcm, cidx, substream) 1115 snd_pcm_sync_stop(substream, false); 1116 1117 pcm_call_notify(pcm, n_disconnect); 1118 for (cidx = 0; cidx < 2; cidx++) { 1119 if (pcm->streams[cidx].dev) 1120 snd_unregister_device(pcm->streams[cidx].dev); 1121 free_chmap(&pcm->streams[cidx]); 1122 } 1123 return 0; 1124 } 1125 1126 #if IS_ENABLED(CONFIG_SND_PCM_OSS) 1127 /** 1128 * snd_pcm_notify - Add/remove the notify list 1129 * @notify: PCM notify list 1130 * @nfree: 0 = register, 1 = unregister 1131 * 1132 * This adds the given notifier to the global list so that the callback is 1133 * called for each registered PCM devices. This exists only for PCM OSS 1134 * emulation, so far. 1135 * 1136 * Return: zero if successful, or a negative error code 1137 */ 1138 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree) 1139 { 1140 struct snd_pcm *pcm; 1141 1142 if (snd_BUG_ON(!notify || 1143 !notify->n_register || 1144 !notify->n_unregister || 1145 !notify->n_disconnect)) 1146 return -EINVAL; 1147 guard(mutex)(®ister_mutex); 1148 if (nfree) { 1149 list_del(¬ify->list); 1150 list_for_each_entry(pcm, &snd_pcm_devices, list) 1151 notify->n_unregister(pcm); 1152 } else { 1153 list_add_tail(¬ify->list, &snd_pcm_notify_list); 1154 list_for_each_entry(pcm, &snd_pcm_devices, list) 1155 notify->n_register(pcm); 1156 } 1157 return 0; 1158 } 1159 EXPORT_SYMBOL(snd_pcm_notify); 1160 #endif /* CONFIG_SND_PCM_OSS */ 1161 1162 #ifdef CONFIG_SND_PROC_FS 1163 /* 1164 * Info interface 1165 */ 1166 1167 static void snd_pcm_proc_read(struct snd_info_entry *entry, 1168 struct snd_info_buffer *buffer) 1169 { 1170 struct snd_pcm *pcm; 1171 1172 guard(mutex)(®ister_mutex); 1173 list_for_each_entry(pcm, &snd_pcm_devices, list) { 1174 snd_iprintf(buffer, "%02i-%02i: %s : %s", 1175 pcm->card->number, pcm->device, pcm->id, pcm->name); 1176 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) 1177 snd_iprintf(buffer, " : playback %i", 1178 pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count); 1179 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) 1180 snd_iprintf(buffer, " : capture %i", 1181 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count); 1182 snd_iprintf(buffer, "\n"); 1183 } 1184 } 1185 1186 static struct snd_info_entry *snd_pcm_proc_entry; 1187 1188 static void snd_pcm_proc_init(void) 1189 { 1190 struct snd_info_entry *entry; 1191 1192 entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL); 1193 if (entry) { 1194 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read); 1195 if (snd_info_register(entry) < 0) { 1196 snd_info_free_entry(entry); 1197 entry = NULL; 1198 } 1199 } 1200 snd_pcm_proc_entry = entry; 1201 } 1202 1203 static void snd_pcm_proc_done(void) 1204 { 1205 snd_info_free_entry(snd_pcm_proc_entry); 1206 } 1207 1208 #else /* !CONFIG_SND_PROC_FS */ 1209 #define snd_pcm_proc_init() 1210 #define snd_pcm_proc_done() 1211 #endif /* CONFIG_SND_PROC_FS */ 1212 1213 1214 /* 1215 * ENTRY functions 1216 */ 1217 1218 static int __init alsa_pcm_init(void) 1219 { 1220 snd_ctl_register_ioctl(snd_pcm_control_ioctl); 1221 snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl); 1222 snd_pcm_proc_init(); 1223 return 0; 1224 } 1225 1226 static void __exit alsa_pcm_exit(void) 1227 { 1228 snd_ctl_unregister_ioctl(snd_pcm_control_ioctl); 1229 snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl); 1230 snd_pcm_proc_done(); 1231 } 1232 1233 module_init(alsa_pcm_init) 1234 module_exit(alsa_pcm_exit) 1235