sound/core/pcm.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Digital Audio (PCM) abstract layer
   4  *  Copyright (c) by Jaroslav Kysela <[email protected]>
   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 <[email protected]>, Abramo Bagnara <[email protected]>");
  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, &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)(&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)(&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)(&register_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)(&register_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)(&register_mutex);
1142         if (nfree) {
1143                 list_del(&notify->list);
1144                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1145                         notify->n_unregister(pcm);
1146         } else {
1147                 list_add_tail(&notify->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)(&register_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)