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 <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                         mutex_lock(&register_mutex);
  95                         device = snd_pcm_next(card, device);
  96                         mutex_unlock(&register_mutex);
  97                         if (put_user(device, (int __user *)arg))
  98                                 return -EFAULT;
  99                         return 0;
 100                 }
 101         case SNDRV_CTL_IOCTL_PCM_INFO:
 102                 {
 103                         struct snd_pcm_info __user *info;
 104                         unsigned int device, subdevice;
 105                         int stream;
 106                         struct snd_pcm *pcm;
 107                         struct snd_pcm_str *pstr;
 108                         struct snd_pcm_substream *substream;
 109                         int err;
 110
 111                         info = (struct snd_pcm_info __user *)arg;
 112                         if (get_user(device, &info->device))
 113                                 return -EFAULT;
 114                         if (get_user(stream, &info->stream))
 115                                 return -EFAULT;
 116                         if (stream < 0 || stream > 1)
 117                                 return -EINVAL;
 118                         stream = array_index_nospec(stream, 2);
 119                         if (get_user(subdevice, &info->subdevice))
 120                                 return -EFAULT;
 121                         mutex_lock(&register_mutex);
 122                         pcm = snd_pcm_get(card, device);
 123                         if (pcm == NULL) {
 124                                 err = -ENXIO;
 125                                 goto _error;
 126                         }
 127                         pstr = &pcm->streams[stream];
 128                         if (pstr->substream_count == 0) {
 129                                 err = -ENOENT;
 130                                 goto _error;
 131                         }
 132                         if (subdevice >= pstr->substream_count) {
 133                                 err = -ENXIO;
 134                                 goto _error;
 135                         }
 136                         for (substream = pstr->substream; substream;
 137                              substream = substream->next)
 138                                 if (substream->number == (int)subdevice)
 139                                         break;
 140                         if (substream == NULL) {
 141                                 err = -ENXIO;
 142                                 goto _error;
 143                         }
 144                         mutex_lock(&pcm->open_mutex);
 145                         err = snd_pcm_info_user(substream, info);
 146                         mutex_unlock(&pcm->open_mutex);
 147                 _error:
 148                         mutex_unlock(&register_mutex);
 149                         return err;
 150                 }
 151         case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
 152                 {
 153                         int val;
 154
 155                         if (get_user(val, (int __user *)arg))
 156                                 return -EFAULT;
 157                         control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
 158                         return 0;
 159                 }
 160         }
 161         return -ENOIOCTLCMD;
 162 }
 163
 164 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
 165
 166 static const char * const snd_pcm_format_names[] = {
 167         FORMAT(S8),
 168         FORMAT(U8),
 169         FORMAT(S16_LE),
 170         FORMAT(S16_BE),
 171         FORMAT(U16_LE),
 172         FORMAT(U16_BE),
 173         FORMAT(S24_LE),
 174         FORMAT(S24_BE),
 175         FORMAT(U24_LE),
 176         FORMAT(U24_BE),
 177         FORMAT(S32_LE),
 178         FORMAT(S32_BE),
 179         FORMAT(U32_LE),
 180         FORMAT(U32_BE),
 181         FORMAT(FLOAT_LE),
 182         FORMAT(FLOAT_BE),
 183         FORMAT(FLOAT64_LE),
 184         FORMAT(FLOAT64_BE),
 185         FORMAT(IEC958_SUBFRAME_LE),
 186         FORMAT(IEC958_SUBFRAME_BE),
 187         FORMAT(MU_LAW),
 188         FORMAT(A_LAW),
 189         FORMAT(IMA_ADPCM),
 190         FORMAT(MPEG),
 191         FORMAT(GSM),
 192         FORMAT(SPECIAL),
 193         FORMAT(S24_3LE),
 194         FORMAT(S24_3BE),
 195         FORMAT(U24_3LE),
 196         FORMAT(U24_3BE),
 197         FORMAT(S20_3LE),
 198         FORMAT(S20_3BE),
 199         FORMAT(U20_3LE),
 200         FORMAT(U20_3BE),
 201         FORMAT(S18_3LE),
 202         FORMAT(S18_3BE),
 203         FORMAT(U18_3LE),
 204         FORMAT(U18_3BE),
 205         FORMAT(G723_24),
 206         FORMAT(G723_24_1B),
 207         FORMAT(G723_40),
 208         FORMAT(G723_40_1B),
 209         FORMAT(DSD_U8),
 210         FORMAT(DSD_U16_LE),
 211         FORMAT(DSD_U32_LE),
 212         FORMAT(DSD_U16_BE),
 213         FORMAT(DSD_U32_BE),
 214 };
 215
 216 /**
 217  * snd_pcm_format_name - Return a name string for the given PCM format
 218  * @format: PCM format
 219  *
 220  * Return: the format name string
 221  */
 222 const char *snd_pcm_format_name(snd_pcm_format_t format)
 223 {
 224         if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
 225                 return "Unknown";
 226         return snd_pcm_format_names[(__force unsigned int)format];
 227 }
 228 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
 229
 230 #ifdef CONFIG_SND_VERBOSE_PROCFS
 231
 232 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
 233 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
 234 #define READY(v) [SNDRV_PCM_READY_##v] = #v
 235 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
 236 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
 237 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
 238 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
 239 #define START(v) [SNDRV_PCM_START_##v] = #v
 240 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
 241
 242 static const char * const snd_pcm_stream_names[] = {
 243         STREAM(PLAYBACK),
 244         STREAM(CAPTURE),
 245 };
 246
 247 static const char * const snd_pcm_state_names[] = {
 248         STATE(OPEN),
 249         STATE(SETUP),
 250         STATE(PREPARED),
 251         STATE(RUNNING),
 252         STATE(XRUN),
 253         STATE(DRAINING),
 254         STATE(PAUSED),
 255         STATE(SUSPENDED),
 256         STATE(DISCONNECTED),
 257 };
 258
 259 static const char * const snd_pcm_access_names[] = {
 260         ACCESS(MMAP_INTERLEAVED),
 261         ACCESS(MMAP_NONINTERLEAVED),
 262         ACCESS(MMAP_COMPLEX),
 263         ACCESS(RW_INTERLEAVED),
 264         ACCESS(RW_NONINTERLEAVED),
 265 };
 266
 267 static const char * const snd_pcm_subformat_names[] = {
 268         SUBFORMAT(STD),
 269 };
 270
 271 static const char * const snd_pcm_tstamp_mode_names[] = {
 272         TSTAMP(NONE),
 273         TSTAMP(ENABLE),
 274 };
 275
 276 static const char *snd_pcm_stream_name(int stream)
 277 {
 278         return snd_pcm_stream_names[stream];
 279 }
 280
 281 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 282 {
 283         return snd_pcm_access_names[(__force int)access];
 284 }
 285
 286 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 287 {
 288         return snd_pcm_subformat_names[(__force int)subformat];
 289 }
 290
 291 static const char *snd_pcm_tstamp_mode_name(int mode)
 292 {
 293         return snd_pcm_tstamp_mode_names[mode];
 294 }
 295
 296 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 297 {
 298         return snd_pcm_state_names[(__force int)state];
 299 }
 300
 301 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 302 #include <linux/soundcard.h>
 303
 304 static const char *snd_pcm_oss_format_name(int format)
 305 {
 306         switch (format) {
 307         case AFMT_MU_LAW:
 308                 return "MU_LAW";
 309         case AFMT_A_LAW:
 310                 return "A_LAW";
 311         case AFMT_IMA_ADPCM:
 312                 return "IMA_ADPCM";
 313         case AFMT_U8:
 314                 return "U8";
 315         case AFMT_S16_LE:
 316                 return "S16_LE";
 317         case AFMT_S16_BE:
 318                 return "S16_BE";
 319         case AFMT_S8:
 320                 return "S8";
 321         case AFMT_U16_LE:
 322                 return "U16_LE";
 323         case AFMT_U16_BE:
 324                 return "U16_BE";
 325         case AFMT_MPEG:
 326                 return "MPEG";
 327         default:
 328                 return "unknown";
 329         }
 330 }
 331 #endif
 332
 333 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 334                                    struct snd_info_buffer *buffer)
 335 {
 336         struct snd_pcm_info *info;
 337         int err;
 338
 339         if (! substream)
 340                 return;
 341
 342         info = kmalloc(sizeof(*info), GFP_KERNEL);
 343         if (!info)
 344                 return;
 345
 346         err = snd_pcm_info(substream, info);
 347         if (err < 0) {
 348                 snd_iprintf(buffer, "error %d\n", err);
 349                 kfree(info);
 350                 return;
 351         }
 352         snd_iprintf(buffer, "card: %d\n", info->card);
 353         snd_iprintf(buffer, "device: %d\n", info->device);
 354         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 355         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 356         snd_iprintf(buffer, "id: %s\n", info->id);
 357         snd_iprintf(buffer, "name: %s\n", info->name);
 358         snd_iprintf(buffer, "subname: %s\n", info->subname);
 359         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 360         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 361         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 362         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 363         kfree(info);
 364 }
 365
 366 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 367                                           struct snd_info_buffer *buffer)
 368 {
 369         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 370                                buffer);
 371 }
 372
 373 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 374                                              struct snd_info_buffer *buffer)
 375 {
 376         snd_pcm_proc_info_read(entry->private_data, buffer);
 377 }
 378
 379 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 380                                                   struct snd_info_buffer *buffer)
 381 {
 382         struct snd_pcm_substream *substream = entry->private_data;
 383         struct snd_pcm_runtime *runtime;
 384
 385         mutex_lock(&substream->pcm->open_mutex);
 386         runtime = substream->runtime;
 387         if (!runtime) {
 388                 snd_iprintf(buffer, "closed\n");
 389                 goto unlock;
 390         }
 391         if (runtime->state == SNDRV_PCM_STATE_OPEN) {
 392                 snd_iprintf(buffer, "no setup\n");
 393                 goto unlock;
 394         }
 395         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 396         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 397         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 398         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 399         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 400         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 401         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 402 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 403         if (substream->oss.oss) {
 404                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 405                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 406                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 407                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 408                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 409                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 410         }
 411 #endif
 412  unlock:
 413         mutex_unlock(&substream->pcm->open_mutex);
 414 }
 415
 416 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 417                                                   struct snd_info_buffer *buffer)
 418 {
 419         struct snd_pcm_substream *substream = entry->private_data;
 420         struct snd_pcm_runtime *runtime;
 421
 422         mutex_lock(&substream->pcm->open_mutex);
 423         runtime = substream->runtime;
 424         if (!runtime) {
 425                 snd_iprintf(buffer, "closed\n");
 426                 goto unlock;
 427         }
 428         if (runtime->state == SNDRV_PCM_STATE_OPEN) {
 429                 snd_iprintf(buffer, "no setup\n");
 430                 goto unlock;
 431         }
 432         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 433         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 434         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 435         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 436         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 437         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 438         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 439         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 440  unlock:
 441         mutex_unlock(&substream->pcm->open_mutex);
 442 }
 443
 444 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 445                                                struct snd_info_buffer *buffer)
 446 {
 447         struct snd_pcm_substream *substream = entry->private_data;
 448         struct snd_pcm_runtime *runtime;
 449         struct snd_pcm_status64 status;
 450         int err;
 451
 452         mutex_lock(&substream->pcm->open_mutex);
 453         runtime = substream->runtime;
 454         if (!runtime) {
 455                 snd_iprintf(buffer, "closed\n");
 456                 goto unlock;
 457         }
 458         memset(&status, 0, sizeof(status));
 459         err = snd_pcm_status64(substream, &status);
 460         if (err < 0) {
 461                 snd_iprintf(buffer, "error %d\n", err);
 462                 goto unlock;
 463         }
 464         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 465         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 466         snd_iprintf(buffer, "trigger_time: %lld.%09lld\n",
 467                 status.trigger_tstamp_sec, status.trigger_tstamp_nsec);
 468         snd_iprintf(buffer, "tstamp      : %lld.%09lld\n",
 469                 status.tstamp_sec, status.tstamp_nsec);
 470         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 471         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 472         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 473         snd_iprintf(buffer, "-----\n");
 474         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 475         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 476  unlock:
 477         mutex_unlock(&substream->pcm->open_mutex);
 478 }
 479
 480 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 481 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
 482                                          struct snd_info_buffer *buffer)
 483 {
 484         struct snd_pcm_substream *substream = entry->private_data;
 485
 486         snd_pcm_stop_xrun(substream);
 487 }
 488
 489 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 490                                     struct snd_info_buffer *buffer)
 491 {
 492         struct snd_pcm_str *pstr = entry->private_data;
 493         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 494 }
 495
 496 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 497                                      struct snd_info_buffer *buffer)
 498 {
 499         struct snd_pcm_str *pstr = entry->private_data;
 500         char line[64];
 501         if (!snd_info_get_line(buffer, line, sizeof(line)))
 502                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 503 }
 504 #endif
 505
 506 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 507 {
 508         struct snd_pcm *pcm = pstr->pcm;
 509         struct snd_info_entry *entry;
 510         char name[16];
 511
 512         sprintf(name, "pcm%i%c", pcm->device,
 513                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 514         entry = snd_info_create_card_entry(pcm->card, name,
 515                                            pcm->card->proc_root);
 516         if (!entry)
 517                 return -ENOMEM;
 518         entry->mode = S_IFDIR | 0555;
 519         pstr->proc_root = entry;
 520         entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
 521         if (entry)
 522                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 523 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 524         entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 525                                            pstr->proc_root);
 526         if (entry) {
 527                 snd_info_set_text_ops(entry, pstr, snd_pcm_xrun_debug_read);
 528                 entry->c.text.write = snd_pcm_xrun_debug_write;
 529                 entry->mode |= 0200;
 530         }
 531 #endif
 532         return 0;
 533 }
 534
 535 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 536 {
 537         snd_info_free_entry(pstr->proc_root);
 538         pstr->proc_root = NULL;
 539         return 0;
 540 }
 541
 542 static struct snd_info_entry *
 543 create_substream_info_entry(struct snd_pcm_substream *substream,
 544                             const char *name,
 545                             void (*read)(struct snd_info_entry *,
 546                                          struct snd_info_buffer *))
 547 {
 548         struct snd_info_entry *entry;
 549
 550         entry = snd_info_create_card_entry(substream->pcm->card, name,
 551                                            substream->proc_root);
 552         if (entry)
 553                 snd_info_set_text_ops(entry, substream, read);
 554         return entry;
 555 }
 556
 557 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 558 {
 559         struct snd_info_entry *entry;
 560         struct snd_card *card;
 561         char name[16];
 562
 563         card = substream->pcm->card;
 564
 565         sprintf(name, "sub%i", substream->number);
 566         entry = snd_info_create_card_entry(card, name,
 567                                            substream->pstr->proc_root);
 568         if (!entry)
 569                 return -ENOMEM;
 570         entry->mode = S_IFDIR | 0555;
 571         substream->proc_root = entry;
 572
 573         create_substream_info_entry(substream, "info",
 574                                     snd_pcm_substream_proc_info_read);
 575         create_substream_info_entry(substream, "hw_params",
 576                                     snd_pcm_substream_proc_hw_params_read);
 577         create_substream_info_entry(substream, "sw_params",
 578                                     snd_pcm_substream_proc_sw_params_read);
 579         create_substream_info_entry(substream, "status",
 580                                     snd_pcm_substream_proc_status_read);
 581
 582 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 583         entry = create_substream_info_entry(substream, "xrun_injection", NULL);
 584         if (entry) {
 585                 entry->c.text.write = snd_pcm_xrun_injection_write;
 586                 entry->mode = S_IFREG | 0200;
 587         }
 588 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
 589
 590         return 0;
 591 }
 592
 593 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 594 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 595 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 596 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 597 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 598
 599 static const struct attribute_group *pcm_dev_attr_groups[];
 600
 601 /*
 602  * PM callbacks: we need to deal only with suspend here, as the resume is
 603  * triggered either from user-space or the driver's resume callback
 604  */
 605 #ifdef CONFIG_PM_SLEEP
 606 static int do_pcm_suspend(struct device *dev)
 607 {
 608         struct snd_pcm_str *pstr = dev_get_drvdata(dev);
 609
 610         if (!pstr->pcm->no_device_suspend)
 611                 snd_pcm_suspend_all(pstr->pcm);
 612         return 0;
 613 }
 614 #endif
 615
 616 static const struct dev_pm_ops pcm_dev_pm_ops = {
 617         SET_SYSTEM_SLEEP_PM_OPS(do_pcm_suspend, NULL)
 618 };
 619
 620 /* device type for PCM -- basically only for passing PM callbacks */
 621 static const struct device_type pcm_dev_type = {
 622         .name = "pcm",
 623         .pm = &pcm_dev_pm_ops,
 624 };
 625
 626 /**
 627  * snd_pcm_new_stream - create a new PCM stream
 628  * @pcm: the pcm instance
 629  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 630  * @substream_count: the number of substreams
 631  *
 632  * Creates a new stream for the pcm.
 633  * The corresponding stream on the pcm must have been empty before
 634  * calling this, i.e. zero must be given to the argument of
 635  * snd_pcm_new().
 636  *
 637  * Return: Zero if successful, or a negative error code on failure.
 638  */
 639 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 640 {
 641         int idx, err;
 642         struct snd_pcm_str *pstr = &pcm->streams[stream];
 643         struct snd_pcm_substream *substream, *prev;
 644
 645 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 646         mutex_init(&pstr->oss.setup_mutex);
 647 #endif
 648         pstr->stream = stream;
 649         pstr->pcm = pcm;
 650         pstr->substream_count = substream_count;
 651         if (!substream_count)
 652                 return 0;
 653
 654         err = snd_device_alloc(&pstr->dev, pcm->card);
 655         if (err < 0)
 656                 return err;
 657         dev_set_name(pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
 658                      stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 659         pstr->dev->groups = pcm_dev_attr_groups;
 660         pstr->dev->type = &pcm_dev_type;
 661         dev_set_drvdata(pstr->dev, pstr);
 662
 663         if (!pcm->internal) {
 664                 err = snd_pcm_stream_proc_init(pstr);
 665                 if (err < 0) {
 666                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 667                         return err;
 668                 }
 669         }
 670         prev = NULL;
 671         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 672                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 673                 if (!substream)
 674                         return -ENOMEM;
 675                 substream->pcm = pcm;
 676                 substream->pstr = pstr;
 677                 substream->number = idx;
 678                 substream->stream = stream;
 679                 sprintf(substream->name, "subdevice #%i", idx);
 680                 substream->buffer_bytes_max = UINT_MAX;
 681                 if (prev == NULL)
 682                         pstr->substream = substream;
 683                 else
 684                         prev->next = substream;
 685
 686                 if (!pcm->internal) {
 687                         err = snd_pcm_substream_proc_init(substream);
 688                         if (err < 0) {
 689                                 pcm_err(pcm,
 690                                         "Error in snd_pcm_stream_proc_init\n");
 691                                 if (prev == NULL)
 692                                         pstr->substream = NULL;
 693                                 else
 694                                         prev->next = NULL;
 695                                 kfree(substream);
 696                                 return err;
 697                         }
 698                 }
 699                 substream->group = &substream->self_group;
 700                 snd_pcm_group_init(&substream->self_group);
 701                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 702                 atomic_set(&substream->mmap_count, 0);
 703                 prev = substream;
 704         }
 705         return 0;
 706 }
 707 EXPORT_SYMBOL(snd_pcm_new_stream);
 708
 709 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 710                 int playback_count, int capture_count, bool internal,
 711                 struct snd_pcm **rpcm)
 712 {
 713         struct snd_pcm *pcm;
 714         int err;
 715         static const struct snd_device_ops ops = {
 716                 .dev_free = snd_pcm_dev_free,
 717                 .dev_register = snd_pcm_dev_register,
 718                 .dev_disconnect = snd_pcm_dev_disconnect,
 719         };
 720         static const struct snd_device_ops internal_ops = {
 721                 .dev_free = snd_pcm_dev_free,
 722         };
 723
 724         if (snd_BUG_ON(!card))
 725                 return -ENXIO;
 726         if (rpcm)
 727                 *rpcm = NULL;
 728         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 729         if (!pcm)
 730                 return -ENOMEM;
 731         pcm->card = card;
 732         pcm->device = device;
 733         pcm->internal = internal;
 734         mutex_init(&pcm->open_mutex);
 735         init_waitqueue_head(&pcm->open_wait);
 736         INIT_LIST_HEAD(&pcm->list);
 737         if (id)
 738                 strscpy(pcm->id, id, sizeof(pcm->id));
 739
 740         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
 741                                  playback_count);
 742         if (err < 0)
 743                 goto free_pcm;
 744
 745         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
 746         if (err < 0)
 747                 goto free_pcm;
 748
 749         err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
 750                              internal ? &internal_ops : &ops);
 751         if (err < 0)
 752                 goto free_pcm;
 753
 754         if (rpcm)
 755                 *rpcm = pcm;
 756         return 0;
 757
 758 free_pcm:
 759         snd_pcm_free(pcm);
 760         return err;
 761 }
 762
 763 /**
 764  * snd_pcm_new - create a new PCM instance
 765  * @card: the card instance
 766  * @id: the id string
 767  * @device: the device index (zero based)
 768  * @playback_count: the number of substreams for playback
 769  * @capture_count: the number of substreams for capture
 770  * @rpcm: the pointer to store the new pcm instance
 771  *
 772  * Creates a new PCM instance.
 773  *
 774  * The pcm operators have to be set afterwards to the new instance
 775  * via snd_pcm_set_ops().
 776  *
 777  * Return: Zero if successful, or a negative error code on failure.
 778  */
 779 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 780                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 781 {
 782         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 783                         false, rpcm);
 784 }
 785 EXPORT_SYMBOL(snd_pcm_new);
 786
 787 /**
 788  * snd_pcm_new_internal - create a new internal PCM instance
 789  * @card: the card instance
 790  * @id: the id string
 791  * @device: the device index (zero based - shared with normal PCMs)
 792  * @playback_count: the number of substreams for playback
 793  * @capture_count: the number of substreams for capture
 794  * @rpcm: the pointer to store the new pcm instance
 795  *
 796  * Creates a new internal PCM instance with no userspace device or procfs
 797  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 798  * will only be used internally by kernel drivers. i.e. it cannot be opened
 799  * by userspace. It provides existing ASoC components drivers with a substream
 800  * and access to any private data.
 801  *
 802  * The pcm operators have to be set afterwards to the new instance
 803  * via snd_pcm_set_ops().
 804  *
 805  * Return: Zero if successful, or a negative error code on failure.
 806  */
 807 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 808         int playback_count, int capture_count,
 809         struct snd_pcm **rpcm)
 810 {
 811         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 812                         true, rpcm);
 813 }
 814 EXPORT_SYMBOL(snd_pcm_new_internal);
 815
 816 static void free_chmap(struct snd_pcm_str *pstr)
 817 {
 818         if (pstr->chmap_kctl) {
 819                 struct snd_card *card = pstr->pcm->card;
 820
 821                 snd_ctl_remove(card, pstr->chmap_kctl);
 822                 pstr->chmap_kctl = NULL;
 823         }
 824 }
 825
 826 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 827 {
 828         struct snd_pcm_substream *substream, *substream_next;
 829 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 830         struct snd_pcm_oss_setup *setup, *setupn;
 831 #endif
 832
 833         /* free all proc files under the stream */
 834         snd_pcm_stream_proc_done(pstr);
 835
 836         substream = pstr->substream;
 837         while (substream) {
 838                 substream_next = substream->next;
 839                 snd_pcm_timer_done(substream);
 840                 kfree(substream);
 841                 substream = substream_next;
 842         }
 843 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 844         for (setup = pstr->oss.setup_list; setup; setup = setupn) {
 845                 setupn = setup->next;
 846                 kfree(setup->task_name);
 847                 kfree(setup);
 848         }
 849 #endif
 850         free_chmap(pstr);
 851         if (pstr->substream_count)
 852                 put_device(pstr->dev);
 853 }
 854
 855 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 856 #define pcm_call_notify(pcm, call)                                      \
 857         do {                                                            \
 858                 struct snd_pcm_notify *_notify;                         \
 859                 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
 860                         _notify->call(pcm);                             \
 861         } while (0)
 862 #else
 863 #define pcm_call_notify(pcm, call) do {} while (0)
 864 #endif
 865
 866 static int snd_pcm_free(struct snd_pcm *pcm)
 867 {
 868         if (!pcm)
 869                 return 0;
 870         if (!pcm->internal)
 871                 pcm_call_notify(pcm, n_unregister);
 872         if (pcm->private_free)
 873                 pcm->private_free(pcm);
 874         snd_pcm_lib_preallocate_free_for_all(pcm);
 875         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
 876         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
 877         kfree(pcm);
 878         return 0;
 879 }
 880
 881 static int snd_pcm_dev_free(struct snd_device *device)
 882 {
 883         struct snd_pcm *pcm = device->device_data;
 884         return snd_pcm_free(pcm);
 885 }
 886
 887 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 888                              struct file *file,
 889                              struct snd_pcm_substream **rsubstream)
 890 {
 891         struct snd_pcm_str * pstr;
 892         struct snd_pcm_substream *substream;
 893         struct snd_pcm_runtime *runtime;
 894         struct snd_card *card;
 895         int prefer_subdevice;
 896         size_t size;
 897
 898         if (snd_BUG_ON(!pcm || !rsubstream))
 899                 return -ENXIO;
 900         if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
 901                        stream != SNDRV_PCM_STREAM_CAPTURE))
 902                 return -EINVAL;
 903         *rsubstream = NULL;
 904         pstr = &pcm->streams[stream];
 905         if (pstr->substream == NULL || pstr->substream_count == 0)
 906                 return -ENODEV;
 907
 908         card = pcm->card;
 909         prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
 910
 911         if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 912                 int opposite = !stream;
 913
 914                 for (substream = pcm->streams[opposite].substream; substream;
 915                      substream = substream->next) {
 916                         if (SUBSTREAM_BUSY(substream))
 917                                 return -EAGAIN;
 918                 }
 919         }
 920
 921         if (file->f_flags & O_APPEND) {
 922                 if (prefer_subdevice < 0) {
 923                         if (pstr->substream_count > 1)
 924                                 return -EINVAL; /* must be unique */
 925                         substream = pstr->substream;
 926                 } else {
 927                         for (substream = pstr->substream; substream;
 928                              substream = substream->next)
 929                                 if (substream->number == prefer_subdevice)
 930                                         break;
 931                 }
 932                 if (! substream)
 933                         return -ENODEV;
 934                 if (! SUBSTREAM_BUSY(substream))
 935                         return -EBADFD;
 936                 substream->ref_count++;
 937                 *rsubstream = substream;
 938                 return 0;
 939         }
 940
 941         for (substream = pstr->substream; substream; substream = substream->next) {
 942                 if (!SUBSTREAM_BUSY(substream) &&
 943                     (prefer_subdevice == -1 ||
 944                      substream->number == prefer_subdevice))
 945                         break;
 946         }
 947         if (substream == NULL)
 948                 return -EAGAIN;
 949
 950         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 951         if (runtime == NULL)
 952                 return -ENOMEM;
 953
 954         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
 955         runtime->status = alloc_pages_exact(size, GFP_KERNEL);
 956         if (runtime->status == NULL) {
 957                 kfree(runtime);
 958                 return -ENOMEM;
 959         }
 960         memset(runtime->status, 0, size);
 961
 962         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
 963         runtime->control = alloc_pages_exact(size, GFP_KERNEL);
 964         if (runtime->control == NULL) {
 965                 free_pages_exact(runtime->status,
 966                                PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
 967                 kfree(runtime);
 968                 return -ENOMEM;
 969         }
 970         memset(runtime->control, 0, size);
 971
 972         init_waitqueue_head(&runtime->sleep);
 973         init_waitqueue_head(&runtime->tsleep);
 974
 975         __snd_pcm_set_state(runtime, SNDRV_PCM_STATE_OPEN);
 976         mutex_init(&runtime->buffer_mutex);
 977         atomic_set(&runtime->buffer_accessing, 0);
 978
 979         substream->runtime = runtime;
 980         substream->private_data = pcm->private_data;
 981         substream->ref_count = 1;
 982         substream->f_flags = file->f_flags;
 983         substream->pid = get_pid(task_pid(current));
 984         pstr->substream_opened++;
 985         *rsubstream = substream;
 986         return 0;
 987 }
 988
 989 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
 990 {
 991         struct snd_pcm_runtime *runtime;
 992
 993         if (PCM_RUNTIME_CHECK(substream))
 994                 return;
 995         runtime = substream->runtime;
 996         if (runtime->private_free != NULL)
 997                 runtime->private_free(runtime);
 998         free_pages_exact(runtime->status,
 999                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1000         free_pages_exact(runtime->control,
1001                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1002         kfree(runtime->hw_constraints.rules);
1003         /* Avoid concurrent access to runtime via PCM timer interface */
1004         if (substream->timer) {
1005                 spin_lock_irq(&substream->timer->lock);
1006                 substream->runtime = NULL;
1007                 spin_unlock_irq(&substream->timer->lock);
1008         } else {
1009                 substream->runtime = NULL;
1010         }
1011         mutex_destroy(&runtime->buffer_mutex);
1012         snd_fasync_free(runtime->fasync);
1013         kfree(runtime);
1014         put_pid(substream->pid);
1015         substream->pid = NULL;
1016         substream->pstr->substream_opened--;
1017 }
1018
1019 static ssize_t pcm_class_show(struct device *dev,
1020                               struct device_attribute *attr, char *buf)
1021 {
1022         struct snd_pcm_str *pstr = dev_get_drvdata(dev);
1023         struct snd_pcm *pcm = pstr->pcm;
1024         const char *str;
1025         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1026                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1027                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1028                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1029                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1030         };
1031
1032         if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1033                 str = "none";
1034         else
1035                 str = strs[pcm->dev_class];
1036         return sysfs_emit(buf, "%s\n", str);
1037 }
1038
1039 static DEVICE_ATTR_RO(pcm_class);
1040 static struct attribute *pcm_dev_attrs[] = {
1041         &dev_attr_pcm_class.attr,
1042         NULL
1043 };
1044
1045 static const struct attribute_group pcm_dev_attr_group = {
1046         .attrs  = pcm_dev_attrs,
1047 };
1048
1049 static const struct attribute_group *pcm_dev_attr_groups[] = {
1050         &pcm_dev_attr_group,
1051         NULL
1052 };
1053
1054 static int snd_pcm_dev_register(struct snd_device *device)
1055 {
1056         int cidx, err;
1057         struct snd_pcm_substream *substream;
1058         struct snd_pcm *pcm;
1059
1060         if (snd_BUG_ON(!device || !device->device_data))
1061                 return -ENXIO;
1062         pcm = device->device_data;
1063
1064         mutex_lock(&register_mutex);
1065         err = snd_pcm_add(pcm);
1066         if (err)
1067                 goto unlock;
1068         for (cidx = 0; cidx < 2; cidx++) {
1069                 int devtype = -1;
1070                 if (pcm->streams[cidx].substream == NULL)
1071                         continue;
1072                 switch (cidx) {
1073                 case SNDRV_PCM_STREAM_PLAYBACK:
1074                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1075                         break;
1076                 case SNDRV_PCM_STREAM_CAPTURE:
1077                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1078                         break;
1079                 }
1080                 /* register pcm */
1081                 err = snd_register_device(devtype, pcm->card, pcm->device,
1082                                           &snd_pcm_f_ops[cidx], pcm,
1083                                           pcm->streams[cidx].dev);
1084                 if (err < 0) {
1085                         list_del_init(&pcm->list);
1086                         goto unlock;
1087                 }
1088
1089                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1090                         snd_pcm_timer_init(substream);
1091         }
1092
1093         pcm_call_notify(pcm, n_register);
1094
1095  unlock:
1096         mutex_unlock(&register_mutex);
1097         return err;
1098 }
1099
1100 static int snd_pcm_dev_disconnect(struct snd_device *device)
1101 {
1102         struct snd_pcm *pcm = device->device_data;
1103         struct snd_pcm_substream *substream;
1104         int cidx;
1105
1106         mutex_lock(&register_mutex);
1107         mutex_lock(&pcm->open_mutex);
1108         wake_up(&pcm->open_wait);
1109         list_del_init(&pcm->list);
1110
1111         for_each_pcm_substream(pcm, cidx, substream) {
1112                 snd_pcm_stream_lock_irq(substream);
1113                 if (substream->runtime) {
1114                         if (snd_pcm_running(substream))
1115                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
1116                         /* to be sure, set the state unconditionally */
1117                         __snd_pcm_set_state(substream->runtime,
1118                                             SNDRV_PCM_STATE_DISCONNECTED);
1119                         wake_up(&substream->runtime->sleep);
1120                         wake_up(&substream->runtime->tsleep);
1121                 }
1122                 snd_pcm_stream_unlock_irq(substream);
1123         }
1124
1125         for_each_pcm_substream(pcm, cidx, substream)
1126                 snd_pcm_sync_stop(substream, false);
1127
1128         pcm_call_notify(pcm, n_disconnect);
1129         for (cidx = 0; cidx < 2; cidx++) {
1130                 if (pcm->streams[cidx].dev)
1131                         snd_unregister_device(pcm->streams[cidx].dev);
1132                 free_chmap(&pcm->streams[cidx]);
1133         }
1134         mutex_unlock(&pcm->open_mutex);
1135         mutex_unlock(&register_mutex);
1136         return 0;
1137 }
1138
1139 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1140 /**
1141  * snd_pcm_notify - Add/remove the notify list
1142  * @notify: PCM notify list
1143  * @nfree: 0 = register, 1 = unregister
1144  *
1145  * This adds the given notifier to the global list so that the callback is
1146  * called for each registered PCM devices.  This exists only for PCM OSS
1147  * emulation, so far.
1148  *
1149  * Return: zero if successful, or a negative error code
1150  */
1151 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1152 {
1153         struct snd_pcm *pcm;
1154
1155         if (snd_BUG_ON(!notify ||
1156                        !notify->n_register ||
1157                        !notify->n_unregister ||
1158                        !notify->n_disconnect))
1159                 return -EINVAL;
1160         mutex_lock(&register_mutex);
1161         if (nfree) {
1162                 list_del(&notify->list);
1163                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1164                         notify->n_unregister(pcm);
1165         } else {
1166                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1167                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1168                         notify->n_register(pcm);
1169         }
1170         mutex_unlock(&register_mutex);
1171         return 0;
1172 }
1173 EXPORT_SYMBOL(snd_pcm_notify);
1174 #endif /* CONFIG_SND_PCM_OSS */
1175
1176 #ifdef CONFIG_SND_PROC_FS
1177 /*
1178  *  Info interface
1179  */
1180
1181 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1182                               struct snd_info_buffer *buffer)
1183 {
1184         struct snd_pcm *pcm;
1185
1186         mutex_lock(&register_mutex);
1187         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1188                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1189                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1190                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1191                         snd_iprintf(buffer, " : playback %i",
1192                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1193                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1194                         snd_iprintf(buffer, " : capture %i",
1195                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1196                 snd_iprintf(buffer, "\n");
1197         }
1198         mutex_unlock(&register_mutex);
1199 }
1200
1201 static struct snd_info_entry *snd_pcm_proc_entry;
1202
1203 static void snd_pcm_proc_init(void)
1204 {
1205         struct snd_info_entry *entry;
1206
1207         entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1208         if (entry) {
1209                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1210                 if (snd_info_register(entry) < 0) {
1211                         snd_info_free_entry(entry);
1212                         entry = NULL;
1213                 }
1214         }
1215         snd_pcm_proc_entry = entry;
1216 }
1217
1218 static void snd_pcm_proc_done(void)
1219 {
1220         snd_info_free_entry(snd_pcm_proc_entry);
1221 }
1222
1223 #else /* !CONFIG_SND_PROC_FS */
1224 #define snd_pcm_proc_init()
1225 #define snd_pcm_proc_done()
1226 #endif /* CONFIG_SND_PROC_FS */
1227
1228
1229 /*
1230  *  ENTRY functions
1231  */
1232
1233 static int __init alsa_pcm_init(void)
1234 {
1235         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1236         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1237         snd_pcm_proc_init();
1238         return 0;
1239 }
1240
1241 static void __exit alsa_pcm_exit(void)
1242 {
1243         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1244         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1245         snd_pcm_proc_done();
1246 }
1247
1248 module_init(alsa_pcm_init)
1249 module_exit(alsa_pcm_exit)