sound/core/pcm.c

   1 /*
   2  *  Digital Audio (PCM) abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4  *
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #include <linux/init.h>
  23 #include <linux/slab.h>
  24 #include <linux/module.h>
  25 #include <linux/time.h>
  26 #include <linux/mutex.h>
  27 #include <linux/device.h>
  28 #include <sound/core.h>
  29 #include <sound/minors.h>
  30 #include <sound/pcm.h>
  31 #include <sound/control.h>
  32 #include <sound/info.h>
  33
  34 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
  35 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
  36 MODULE_LICENSE("GPL");
  37
  38 static LIST_HEAD(snd_pcm_devices);
  39 static LIST_HEAD(snd_pcm_notify_list);
  40 static DEFINE_MUTEX(register_mutex);
  41
  42 static int snd_pcm_free(struct snd_pcm *pcm);
  43 static int snd_pcm_dev_free(struct snd_device *device);
  44 static int snd_pcm_dev_register(struct snd_device *device);
  45 static int snd_pcm_dev_disconnect(struct snd_device *device);
  46
  47 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
  48 {
  49         struct snd_pcm *pcm;
  50
  51         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  52                 if (pcm->internal)
  53                         continue;
  54                 if (pcm->card == card && pcm->device == device)
  55                         return pcm;
  56         }
  57         return NULL;
  58 }
  59
  60 static int snd_pcm_next(struct snd_card *card, int device)
  61 {
  62         struct snd_pcm *pcm;
  63
  64         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  65                 if (pcm->internal)
  66                         continue;
  67                 if (pcm->card == card && pcm->device > device)
  68                         return pcm->device;
  69                 else if (pcm->card->number > card->number)
  70                         return -1;
  71         }
  72         return -1;
  73 }
  74
  75 static int snd_pcm_add(struct snd_pcm *newpcm)
  76 {
  77         struct snd_pcm *pcm;
  78
  79         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  80                 if (pcm->card == newpcm->card && pcm->device == newpcm->device)
  81                         return -EBUSY;
  82                 if (pcm->card->number > newpcm->card->number ||
  83                                 (pcm->card == newpcm->card &&
  84                                 pcm->device > newpcm->device)) {
  85                         list_add(&newpcm->list, pcm->list.prev);
  86                         return 0;
  87                 }
  88         }
  89         list_add_tail(&newpcm->list, &snd_pcm_devices);
  90         return 0;
  91 }
  92
  93 static int snd_pcm_control_ioctl(struct snd_card *card,
  94                                  struct snd_ctl_file *control,
  95                                  unsigned int cmd, unsigned long arg)
  96 {
  97         switch (cmd) {
  98         case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
  99                 {
 100                         int device;
 101
 102                         if (get_user(device, (int __user *)arg))
 103                                 return -EFAULT;
 104                         mutex_lock(&register_mutex);
 105                         device = snd_pcm_next(card, device);
 106                         mutex_unlock(&register_mutex);
 107                         if (put_user(device, (int __user *)arg))
 108                                 return -EFAULT;
 109                         return 0;
 110                 }
 111         case SNDRV_CTL_IOCTL_PCM_INFO:
 112                 {
 113                         struct snd_pcm_info __user *info;
 114                         unsigned int device, subdevice;
 115                         int stream;
 116                         struct snd_pcm *pcm;
 117                         struct snd_pcm_str *pstr;
 118                         struct snd_pcm_substream *substream;
 119                         int err;
 120
 121                         info = (struct snd_pcm_info __user *)arg;
 122                         if (get_user(device, &info->device))
 123                                 return -EFAULT;
 124                         if (get_user(stream, &info->stream))
 125                                 return -EFAULT;
 126                         if (stream < 0 || stream > 1)
 127                                 return -EINVAL;
 128                         if (get_user(subdevice, &info->subdevice))
 129                                 return -EFAULT;
 130                         mutex_lock(&register_mutex);
 131                         pcm = snd_pcm_get(card, device);
 132                         if (pcm == NULL) {
 133                                 err = -ENXIO;
 134                                 goto _error;
 135                         }
 136                         pstr = &pcm->streams[stream];
 137                         if (pstr->substream_count == 0) {
 138                                 err = -ENOENT;
 139                                 goto _error;
 140                         }
 141                         if (subdevice >= pstr->substream_count) {
 142                                 err = -ENXIO;
 143                                 goto _error;
 144                         }
 145                         for (substream = pstr->substream; substream;
 146                              substream = substream->next)
 147                                 if (substream->number == (int)subdevice)
 148                                         break;
 149                         if (substream == NULL) {
 150                                 err = -ENXIO;
 151                                 goto _error;
 152                         }
 153                         err = snd_pcm_info_user(substream, info);
 154                 _error:
 155                         mutex_unlock(&register_mutex);
 156                         return err;
 157                 }
 158         case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
 159                 {
 160                         int val;
 161
 162                         if (get_user(val, (int __user *)arg))
 163                                 return -EFAULT;
 164                         control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
 165                         return 0;
 166                 }
 167         }
 168         return -ENOIOCTLCMD;
 169 }
 170
 171 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
 172
 173 static char *snd_pcm_format_names[] = {
 174         FORMAT(S8),
 175         FORMAT(U8),
 176         FORMAT(S16_LE),
 177         FORMAT(S16_BE),
 178         FORMAT(U16_LE),
 179         FORMAT(U16_BE),
 180         FORMAT(S24_LE),
 181         FORMAT(S24_BE),
 182         FORMAT(U24_LE),
 183         FORMAT(U24_BE),
 184         FORMAT(S32_LE),
 185         FORMAT(S32_BE),
 186         FORMAT(U32_LE),
 187         FORMAT(U32_BE),
 188         FORMAT(FLOAT_LE),
 189         FORMAT(FLOAT_BE),
 190         FORMAT(FLOAT64_LE),
 191         FORMAT(FLOAT64_BE),
 192         FORMAT(IEC958_SUBFRAME_LE),
 193         FORMAT(IEC958_SUBFRAME_BE),
 194         FORMAT(MU_LAW),
 195         FORMAT(A_LAW),
 196         FORMAT(IMA_ADPCM),
 197         FORMAT(MPEG),
 198         FORMAT(GSM),
 199         FORMAT(SPECIAL),
 200         FORMAT(S24_3LE),
 201         FORMAT(S24_3BE),
 202         FORMAT(U24_3LE),
 203         FORMAT(U24_3BE),
 204         FORMAT(S20_3LE),
 205         FORMAT(S20_3BE),
 206         FORMAT(U20_3LE),
 207         FORMAT(U20_3BE),
 208         FORMAT(S18_3LE),
 209         FORMAT(S18_3BE),
 210         FORMAT(U18_3LE),
 211         FORMAT(U18_3BE),
 212         FORMAT(G723_24),
 213         FORMAT(G723_24_1B),
 214         FORMAT(G723_40),
 215         FORMAT(G723_40_1B),
 216         FORMAT(DSD_U8),
 217         FORMAT(DSD_U16_LE),
 218         FORMAT(DSD_U32_LE),
 219         FORMAT(DSD_U16_BE),
 220         FORMAT(DSD_U32_BE),
 221 };
 222
 223 /**
 224  * snd_pcm_format_name - Return a name string for the given PCM format
 225  * @format: PCM format
 226  */
 227 const char *snd_pcm_format_name(snd_pcm_format_t format)
 228 {
 229         if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
 230                 return "Unknown";
 231         return snd_pcm_format_names[(__force unsigned int)format];
 232 }
 233 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
 234
 235 #ifdef CONFIG_SND_VERBOSE_PROCFS
 236
 237 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
 238 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
 239 #define READY(v) [SNDRV_PCM_READY_##v] = #v
 240 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
 241 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
 242 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
 243 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
 244 #define START(v) [SNDRV_PCM_START_##v] = #v
 245 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
 246
 247 static char *snd_pcm_stream_names[] = {
 248         STREAM(PLAYBACK),
 249         STREAM(CAPTURE),
 250 };
 251
 252 static char *snd_pcm_state_names[] = {
 253         STATE(OPEN),
 254         STATE(SETUP),
 255         STATE(PREPARED),
 256         STATE(RUNNING),
 257         STATE(XRUN),
 258         STATE(DRAINING),
 259         STATE(PAUSED),
 260         STATE(SUSPENDED),
 261 };
 262
 263 static char *snd_pcm_access_names[] = {
 264         ACCESS(MMAP_INTERLEAVED),
 265         ACCESS(MMAP_NONINTERLEAVED),
 266         ACCESS(MMAP_COMPLEX),
 267         ACCESS(RW_INTERLEAVED),
 268         ACCESS(RW_NONINTERLEAVED),
 269 };
 270
 271 static char *snd_pcm_subformat_names[] = {
 272         SUBFORMAT(STD),
 273 };
 274
 275 static char *snd_pcm_tstamp_mode_names[] = {
 276         TSTAMP(NONE),
 277         TSTAMP(ENABLE),
 278 };
 279
 280 static const char *snd_pcm_stream_name(int stream)
 281 {
 282         return snd_pcm_stream_names[stream];
 283 }
 284
 285 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 286 {
 287         return snd_pcm_access_names[(__force int)access];
 288 }
 289
 290 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 291 {
 292         return snd_pcm_subformat_names[(__force int)subformat];
 293 }
 294
 295 static const char *snd_pcm_tstamp_mode_name(int mode)
 296 {
 297         return snd_pcm_tstamp_mode_names[mode];
 298 }
 299
 300 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 301 {
 302         return snd_pcm_state_names[(__force int)state];
 303 }
 304
 305 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 306 #include <linux/soundcard.h>
 307
 308 static const char *snd_pcm_oss_format_name(int format)
 309 {
 310         switch (format) {
 311         case AFMT_MU_LAW:
 312                 return "MU_LAW";
 313         case AFMT_A_LAW:
 314                 return "A_LAW";
 315         case AFMT_IMA_ADPCM:
 316                 return "IMA_ADPCM";
 317         case AFMT_U8:
 318                 return "U8";
 319         case AFMT_S16_LE:
 320                 return "S16_LE";
 321         case AFMT_S16_BE:
 322                 return "S16_BE";
 323         case AFMT_S8:
 324                 return "S8";
 325         case AFMT_U16_LE:
 326                 return "U16_LE";
 327         case AFMT_U16_BE:
 328                 return "U16_BE";
 329         case AFMT_MPEG:
 330                 return "MPEG";
 331         default:
 332                 return "unknown";
 333         }
 334 }
 335 #endif
 336
 337 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 338                                    struct snd_info_buffer *buffer)
 339 {
 340         struct snd_pcm_info *info;
 341         int err;
 342
 343         if (! substream)
 344                 return;
 345
 346         info = kmalloc(sizeof(*info), GFP_KERNEL);
 347         if (! info) {
 348                 pcm_dbg(substream->pcm,
 349                         "snd_pcm_proc_info_read: cannot malloc\n");
 350                 return;
 351         }
 352
 353         err = snd_pcm_info(substream, info);
 354         if (err < 0) {
 355                 snd_iprintf(buffer, "error %d\n", err);
 356                 kfree(info);
 357                 return;
 358         }
 359         snd_iprintf(buffer, "card: %d\n", info->card);
 360         snd_iprintf(buffer, "device: %d\n", info->device);
 361         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 362         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 363         snd_iprintf(buffer, "id: %s\n", info->id);
 364         snd_iprintf(buffer, "name: %s\n", info->name);
 365         snd_iprintf(buffer, "subname: %s\n", info->subname);
 366         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 367         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 368         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 369         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 370         kfree(info);
 371 }
 372
 373 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 374                                           struct snd_info_buffer *buffer)
 375 {
 376         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 377                                buffer);
 378 }
 379
 380 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 381                                              struct snd_info_buffer *buffer)
 382 {
 383         snd_pcm_proc_info_read(entry->private_data, buffer);
 384 }
 385
 386 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 387                                                   struct snd_info_buffer *buffer)
 388 {
 389         struct snd_pcm_substream *substream = entry->private_data;
 390         struct snd_pcm_runtime *runtime;
 391
 392         mutex_lock(&substream->pcm->open_mutex);
 393         runtime = substream->runtime;
 394         if (!runtime) {
 395                 snd_iprintf(buffer, "closed\n");
 396                 goto unlock;
 397         }
 398         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 399                 snd_iprintf(buffer, "no setup\n");
 400                 goto unlock;
 401         }
 402         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 403         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 404         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 405         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 406         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 407         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 408         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 409 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 410         if (substream->oss.oss) {
 411                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 412                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 413                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 414                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 415                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 416                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 417         }
 418 #endif
 419  unlock:
 420         mutex_unlock(&substream->pcm->open_mutex);
 421 }
 422
 423 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 424                                                   struct snd_info_buffer *buffer)
 425 {
 426         struct snd_pcm_substream *substream = entry->private_data;
 427         struct snd_pcm_runtime *runtime;
 428
 429         mutex_lock(&substream->pcm->open_mutex);
 430         runtime = substream->runtime;
 431         if (!runtime) {
 432                 snd_iprintf(buffer, "closed\n");
 433                 goto unlock;
 434         }
 435         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 436                 snd_iprintf(buffer, "no setup\n");
 437                 goto unlock;
 438         }
 439         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 440         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 441         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 442         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 443         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 444         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 445         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 446         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 447  unlock:
 448         mutex_unlock(&substream->pcm->open_mutex);
 449 }
 450
 451 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 452                                                struct snd_info_buffer *buffer)
 453 {
 454         struct snd_pcm_substream *substream = entry->private_data;
 455         struct snd_pcm_runtime *runtime;
 456         struct snd_pcm_status status;
 457         int err;
 458
 459         mutex_lock(&substream->pcm->open_mutex);
 460         runtime = substream->runtime;
 461         if (!runtime) {
 462                 snd_iprintf(buffer, "closed\n");
 463                 goto unlock;
 464         }
 465         memset(&status, 0, sizeof(status));
 466         err = snd_pcm_status(substream, &status);
 467         if (err < 0) {
 468                 snd_iprintf(buffer, "error %d\n", err);
 469                 goto unlock;
 470         }
 471         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 472         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 473         snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
 474                 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
 475         snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
 476                 status.tstamp.tv_sec, status.tstamp.tv_nsec);
 477         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 478         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 479         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 480         snd_iprintf(buffer, "-----\n");
 481         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 482         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 483  unlock:
 484         mutex_unlock(&substream->pcm->open_mutex);
 485 }
 486
 487 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 488 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
 489                                          struct snd_info_buffer *buffer)
 490 {
 491         struct snd_pcm_substream *substream = entry->private_data;
 492         struct snd_pcm_runtime *runtime;
 493
 494         snd_pcm_stream_lock_irq(substream);
 495         runtime = substream->runtime;
 496         if (runtime && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
 497                 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 498         snd_pcm_stream_unlock_irq(substream);
 499 }
 500
 501 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 502                                     struct snd_info_buffer *buffer)
 503 {
 504         struct snd_pcm_str *pstr = entry->private_data;
 505         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 506 }
 507
 508 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 509                                      struct snd_info_buffer *buffer)
 510 {
 511         struct snd_pcm_str *pstr = entry->private_data;
 512         char line[64];
 513         if (!snd_info_get_line(buffer, line, sizeof(line)))
 514                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 515 }
 516 #endif
 517
 518 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 519 {
 520         struct snd_pcm *pcm = pstr->pcm;
 521         struct snd_info_entry *entry;
 522         char name[16];
 523
 524         sprintf(name, "pcm%i%c", pcm->device,
 525                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 526         if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
 527                 return -ENOMEM;
 528         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 529         if (snd_info_register(entry) < 0) {
 530                 snd_info_free_entry(entry);
 531                 return -ENOMEM;
 532         }
 533         pstr->proc_root = entry;
 534
 535         if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
 536                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 537                 if (snd_info_register(entry) < 0) {
 538                         snd_info_free_entry(entry);
 539                         entry = NULL;
 540                 }
 541         }
 542         pstr->proc_info_entry = entry;
 543
 544 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 545         if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 546                                                 pstr->proc_root)) != NULL) {
 547                 entry->c.text.read = snd_pcm_xrun_debug_read;
 548                 entry->c.text.write = snd_pcm_xrun_debug_write;
 549                 entry->mode |= S_IWUSR;
 550                 entry->private_data = pstr;
 551                 if (snd_info_register(entry) < 0) {
 552                         snd_info_free_entry(entry);
 553                         entry = NULL;
 554                 }
 555         }
 556         pstr->proc_xrun_debug_entry = entry;
 557 #endif
 558         return 0;
 559 }
 560
 561 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 562 {
 563 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 564         snd_info_free_entry(pstr->proc_xrun_debug_entry);
 565         pstr->proc_xrun_debug_entry = NULL;
 566 #endif
 567         snd_info_free_entry(pstr->proc_info_entry);
 568         pstr->proc_info_entry = NULL;
 569         snd_info_free_entry(pstr->proc_root);
 570         pstr->proc_root = NULL;
 571         return 0;
 572 }
 573
 574 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 575 {
 576         struct snd_info_entry *entry;
 577         struct snd_card *card;
 578         char name[16];
 579
 580         card = substream->pcm->card;
 581
 582         sprintf(name, "sub%i", substream->number);
 583         if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
 584                 return -ENOMEM;
 585         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 586         if (snd_info_register(entry) < 0) {
 587                 snd_info_free_entry(entry);
 588                 return -ENOMEM;
 589         }
 590         substream->proc_root = entry;
 591
 592         if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
 593                 snd_info_set_text_ops(entry, substream,
 594                                       snd_pcm_substream_proc_info_read);
 595                 if (snd_info_register(entry) < 0) {
 596                         snd_info_free_entry(entry);
 597                         entry = NULL;
 598                 }
 599         }
 600         substream->proc_info_entry = entry;
 601
 602         if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
 603                 snd_info_set_text_ops(entry, substream,
 604                                       snd_pcm_substream_proc_hw_params_read);
 605                 if (snd_info_register(entry) < 0) {
 606                         snd_info_free_entry(entry);
 607                         entry = NULL;
 608                 }
 609         }
 610         substream->proc_hw_params_entry = entry;
 611
 612         if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
 613                 snd_info_set_text_ops(entry, substream,
 614                                       snd_pcm_substream_proc_sw_params_read);
 615                 if (snd_info_register(entry) < 0) {
 616                         snd_info_free_entry(entry);
 617                         entry = NULL;
 618                 }
 619         }
 620         substream->proc_sw_params_entry = entry;
 621
 622         if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
 623                 snd_info_set_text_ops(entry, substream,
 624                                       snd_pcm_substream_proc_status_read);
 625                 if (snd_info_register(entry) < 0) {
 626                         snd_info_free_entry(entry);
 627                         entry = NULL;
 628                 }
 629         }
 630         substream->proc_status_entry = entry;
 631
 632 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 633         entry = snd_info_create_card_entry(card, "xrun_injection",
 634                                            substream->proc_root);
 635         if (entry) {
 636                 entry->private_data = substream;
 637                 entry->c.text.read = NULL;
 638                 entry->c.text.write = snd_pcm_xrun_injection_write;
 639                 entry->mode = S_IFREG | S_IWUSR;
 640                 if (snd_info_register(entry) < 0) {
 641                         snd_info_free_entry(entry);
 642                         entry = NULL;
 643                 }
 644         }
 645         substream->proc_xrun_injection_entry = entry;
 646 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
 647
 648         return 0;
 649 }
 650
 651 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 652 {
 653         snd_info_free_entry(substream->proc_info_entry);
 654         substream->proc_info_entry = NULL;
 655         snd_info_free_entry(substream->proc_hw_params_entry);
 656         substream->proc_hw_params_entry = NULL;
 657         snd_info_free_entry(substream->proc_sw_params_entry);
 658         substream->proc_sw_params_entry = NULL;
 659         snd_info_free_entry(substream->proc_status_entry);
 660         substream->proc_status_entry = NULL;
 661 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 662         snd_info_free_entry(substream->proc_xrun_injection_entry);
 663         substream->proc_xrun_injection_entry = NULL;
 664 #endif
 665         snd_info_free_entry(substream->proc_root);
 666         substream->proc_root = NULL;
 667         return 0;
 668 }
 669 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 670 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 671 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 672 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 673 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
 674 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 675
 676 static const struct attribute_group *pcm_dev_attr_groups[];
 677
 678 /**
 679  * snd_pcm_new_stream - create a new PCM stream
 680  * @pcm: the pcm instance
 681  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 682  * @substream_count: the number of substreams
 683  *
 684  * Creates a new stream for the pcm.
 685  * The corresponding stream on the pcm must have been empty before
 686  * calling this, i.e. zero must be given to the argument of
 687  * snd_pcm_new().
 688  *
 689  * Return: Zero if successful, or a negative error code on failure.
 690  */
 691 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 692 {
 693         int idx, err;
 694         struct snd_pcm_str *pstr = &pcm->streams[stream];
 695         struct snd_pcm_substream *substream, *prev;
 696
 697 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 698         mutex_init(&pstr->oss.setup_mutex);
 699 #endif
 700         pstr->stream = stream;
 701         pstr->pcm = pcm;
 702         pstr->substream_count = substream_count;
 703         if (!substream_count)
 704                 return 0;
 705
 706         snd_device_initialize(&pstr->dev, pcm->card);
 707         pstr->dev.groups = pcm_dev_attr_groups;
 708         dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
 709                      stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 710
 711         if (!pcm->internal) {
 712                 err = snd_pcm_stream_proc_init(pstr);
 713                 if (err < 0) {
 714                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 715                         return err;
 716                 }
 717         }
 718         prev = NULL;
 719         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 720                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 721                 if (substream == NULL) {
 722                         pcm_err(pcm, "Cannot allocate PCM substream\n");
 723                         return -ENOMEM;
 724                 }
 725                 substream->pcm = pcm;
 726                 substream->pstr = pstr;
 727                 substream->number = idx;
 728                 substream->stream = stream;
 729                 sprintf(substream->name, "subdevice #%i", idx);
 730                 substream->buffer_bytes_max = UINT_MAX;
 731                 if (prev == NULL)
 732                         pstr->substream = substream;
 733                 else
 734                         prev->next = substream;
 735
 736                 if (!pcm->internal) {
 737                         err = snd_pcm_substream_proc_init(substream);
 738                         if (err < 0) {
 739                                 pcm_err(pcm,
 740                                         "Error in snd_pcm_stream_proc_init\n");
 741                                 if (prev == NULL)
 742                                         pstr->substream = NULL;
 743                                 else
 744                                         prev->next = NULL;
 745                                 kfree(substream);
 746                                 return err;
 747                         }
 748                 }
 749                 substream->group = &substream->self_group;
 750                 spin_lock_init(&substream->self_group.lock);
 751                 mutex_init(&substream->self_group.mutex);
 752                 INIT_LIST_HEAD(&substream->self_group.substreams);
 753                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 754                 atomic_set(&substream->mmap_count, 0);
 755                 prev = substream;
 756         }
 757         return 0;
 758 }
 759 EXPORT_SYMBOL(snd_pcm_new_stream);
 760
 761 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 762                 int playback_count, int capture_count, bool internal,
 763                 struct snd_pcm **rpcm)
 764 {
 765         struct snd_pcm *pcm;
 766         int err;
 767         static struct snd_device_ops ops = {
 768                 .dev_free = snd_pcm_dev_free,
 769                 .dev_register = snd_pcm_dev_register,
 770                 .dev_disconnect = snd_pcm_dev_disconnect,
 771         };
 772
 773         if (snd_BUG_ON(!card))
 774                 return -ENXIO;
 775         if (rpcm)
 776                 *rpcm = NULL;
 777         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 778         if (pcm == NULL) {
 779                 dev_err(card->dev, "Cannot allocate PCM\n");
 780                 return -ENOMEM;
 781         }
 782         pcm->card = card;
 783         pcm->device = device;
 784         pcm->internal = internal;
 785         if (id)
 786                 strlcpy(pcm->id, id, sizeof(pcm->id));
 787         if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
 788                 snd_pcm_free(pcm);
 789                 return err;
 790         }
 791         if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
 792                 snd_pcm_free(pcm);
 793                 return err;
 794         }
 795         mutex_init(&pcm->open_mutex);
 796         init_waitqueue_head(&pcm->open_wait);
 797         if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
 798                 snd_pcm_free(pcm);
 799                 return err;
 800         }
 801         if (rpcm)
 802                 *rpcm = pcm;
 803         return 0;
 804 }
 805
 806 /**
 807  * snd_pcm_new - create a new PCM instance
 808  * @card: the card instance
 809  * @id: the id string
 810  * @device: the device index (zero based)
 811  * @playback_count: the number of substreams for playback
 812  * @capture_count: the number of substreams for capture
 813  * @rpcm: the pointer to store the new pcm instance
 814  *
 815  * Creates a new PCM instance.
 816  *
 817  * The pcm operators have to be set afterwards to the new instance
 818  * via snd_pcm_set_ops().
 819  *
 820  * Return: Zero if successful, or a negative error code on failure.
 821  */
 822 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 823                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 824 {
 825         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 826                         false, rpcm);
 827 }
 828 EXPORT_SYMBOL(snd_pcm_new);
 829
 830 /**
 831  * snd_pcm_new_internal - create a new internal PCM instance
 832  * @card: the card instance
 833  * @id: the id string
 834  * @device: the device index (zero based - shared with normal PCMs)
 835  * @playback_count: the number of substreams for playback
 836  * @capture_count: the number of substreams for capture
 837  * @rpcm: the pointer to store the new pcm instance
 838  *
 839  * Creates a new internal PCM instance with no userspace device or procfs
 840  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 841  * will only be used internally by kernel drivers. i.e. it cannot be opened
 842  * by userspace. It provides existing ASoC components drivers with a substream
 843  * and access to any private data.
 844  *
 845  * The pcm operators have to be set afterwards to the new instance
 846  * via snd_pcm_set_ops().
 847  *
 848  * Return: Zero if successful, or a negative error code on failure.
 849  */
 850 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 851         int playback_count, int capture_count,
 852         struct snd_pcm **rpcm)
 853 {
 854         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 855                         true, rpcm);
 856 }
 857 EXPORT_SYMBOL(snd_pcm_new_internal);
 858
 859 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 860 {
 861         struct snd_pcm_substream *substream, *substream_next;
 862 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 863         struct snd_pcm_oss_setup *setup, *setupn;
 864 #endif
 865         substream = pstr->substream;
 866         while (substream) {
 867                 substream_next = substream->next;
 868                 snd_pcm_timer_done(substream);
 869                 snd_pcm_substream_proc_done(substream);
 870                 kfree(substream);
 871                 substream = substream_next;
 872         }
 873         snd_pcm_stream_proc_done(pstr);
 874 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 875         for (setup = pstr->oss.setup_list; setup; setup = setupn) {
 876                 setupn = setup->next;
 877                 kfree(setup->task_name);
 878                 kfree(setup);
 879         }
 880 #endif
 881         if (pstr->substream_count)
 882                 put_device(&pstr->dev);
 883 }
 884
 885 static int snd_pcm_free(struct snd_pcm *pcm)
 886 {
 887         struct snd_pcm_notify *notify;
 888
 889         if (!pcm)
 890                 return 0;
 891         list_for_each_entry(notify, &snd_pcm_notify_list, list) {
 892                 notify->n_unregister(pcm);
 893         }
 894         if (pcm->private_free)
 895                 pcm->private_free(pcm);
 896         snd_pcm_lib_preallocate_free_for_all(pcm);
 897         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
 898         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
 899         kfree(pcm);
 900         return 0;
 901 }
 902
 903 static int snd_pcm_dev_free(struct snd_device *device)
 904 {
 905         struct snd_pcm *pcm = device->device_data;
 906         return snd_pcm_free(pcm);
 907 }
 908
 909 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 910                              struct file *file,
 911                              struct snd_pcm_substream **rsubstream)
 912 {
 913         struct snd_pcm_str * pstr;
 914         struct snd_pcm_substream *substream;
 915         struct snd_pcm_runtime *runtime;
 916         struct snd_card *card;
 917         int prefer_subdevice;
 918         size_t size;
 919
 920         if (snd_BUG_ON(!pcm || !rsubstream))
 921                 return -ENXIO;
 922         *rsubstream = NULL;
 923         pstr = &pcm->streams[stream];
 924         if (pstr->substream == NULL || pstr->substream_count == 0)
 925                 return -ENODEV;
 926
 927         card = pcm->card;
 928         prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
 929
 930         switch (stream) {
 931         case SNDRV_PCM_STREAM_PLAYBACK:
 932                 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 933                         for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
 934                                 if (SUBSTREAM_BUSY(substream))
 935                                         return -EAGAIN;
 936                         }
 937                 }
 938                 break;
 939         case SNDRV_PCM_STREAM_CAPTURE:
 940                 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 941                         for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
 942                                 if (SUBSTREAM_BUSY(substream))
 943                                         return -EAGAIN;
 944                         }
 945                 }
 946                 break;
 947         default:
 948                 return -EINVAL;
 949         }
 950
 951         if (file->f_flags & O_APPEND) {
 952                 if (prefer_subdevice < 0) {
 953                         if (pstr->substream_count > 1)
 954                                 return -EINVAL; /* must be unique */
 955                         substream = pstr->substream;
 956                 } else {
 957                         for (substream = pstr->substream; substream;
 958                              substream = substream->next)
 959                                 if (substream->number == prefer_subdevice)
 960                                         break;
 961                 }
 962                 if (! substream)
 963                         return -ENODEV;
 964                 if (! SUBSTREAM_BUSY(substream))
 965                         return -EBADFD;
 966                 substream->ref_count++;
 967                 *rsubstream = substream;
 968                 return 0;
 969         }
 970
 971         if (prefer_subdevice >= 0) {
 972                 for (substream = pstr->substream; substream; substream = substream->next)
 973                         if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
 974                                 goto __ok;
 975         }
 976         for (substream = pstr->substream; substream; substream = substream->next)
 977                 if (!SUBSTREAM_BUSY(substream))
 978                         break;
 979       __ok:
 980         if (substream == NULL)
 981                 return -EAGAIN;
 982
 983         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 984         if (runtime == NULL)
 985                 return -ENOMEM;
 986
 987         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
 988         runtime->status = snd_malloc_pages(size, GFP_KERNEL);
 989         if (runtime->status == NULL) {
 990                 kfree(runtime);
 991                 return -ENOMEM;
 992         }
 993         memset((void*)runtime->status, 0, size);
 994
 995         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
 996         runtime->control = snd_malloc_pages(size, GFP_KERNEL);
 997         if (runtime->control == NULL) {
 998                 snd_free_pages((void*)runtime->status,
 999                                PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1000                 kfree(runtime);
1001                 return -ENOMEM;
1002         }
1003         memset((void*)runtime->control, 0, size);
1004
1005         init_waitqueue_head(&runtime->sleep);
1006         init_waitqueue_head(&runtime->tsleep);
1007
1008         runtime->status->state = SNDRV_PCM_STATE_OPEN;
1009
1010         substream->runtime = runtime;
1011         substream->private_data = pcm->private_data;
1012         substream->ref_count = 1;
1013         substream->f_flags = file->f_flags;
1014         substream->pid = get_pid(task_pid(current));
1015         pstr->substream_opened++;
1016         *rsubstream = substream;
1017         return 0;
1018 }
1019
1020 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1021 {
1022         struct snd_pcm_runtime *runtime;
1023
1024         if (PCM_RUNTIME_CHECK(substream))
1025                 return;
1026         runtime = substream->runtime;
1027         if (runtime->private_free != NULL)
1028                 runtime->private_free(runtime);
1029         snd_free_pages((void*)runtime->status,
1030                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1031         snd_free_pages((void*)runtime->control,
1032                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1033         kfree(runtime->hw_constraints.rules);
1034 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
1035         kfree(runtime->hwptr_log);
1036 #endif
1037         kfree(runtime);
1038         substream->runtime = NULL;
1039         put_pid(substream->pid);
1040         substream->pid = NULL;
1041         substream->pstr->substream_opened--;
1042 }
1043
1044 static ssize_t show_pcm_class(struct device *dev,
1045                               struct device_attribute *attr, char *buf)
1046 {
1047         struct snd_pcm *pcm;
1048         const char *str;
1049         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1050                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1051                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1052                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1053                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1054         };
1055
1056         if (! (pcm = dev_get_drvdata(dev)) ||
1057             pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1058                 str = "none";
1059         else
1060                 str = strs[pcm->dev_class];
1061         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1062 }
1063
1064 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1065 static struct attribute *pcm_dev_attrs[] = {
1066         &dev_attr_pcm_class.attr,
1067         NULL
1068 };
1069
1070 static struct attribute_group pcm_dev_attr_group = {
1071         .attrs  = pcm_dev_attrs,
1072 };
1073
1074 static const struct attribute_group *pcm_dev_attr_groups[] = {
1075         &pcm_dev_attr_group,
1076         NULL
1077 };
1078
1079 static int snd_pcm_dev_register(struct snd_device *device)
1080 {
1081         int cidx, err;
1082         struct snd_pcm_substream *substream;
1083         struct snd_pcm_notify *notify;
1084         struct snd_pcm *pcm;
1085
1086         if (snd_BUG_ON(!device || !device->device_data))
1087                 return -ENXIO;
1088         pcm = device->device_data;
1089         mutex_lock(&register_mutex);
1090         err = snd_pcm_add(pcm);
1091         if (err) {
1092                 mutex_unlock(&register_mutex);
1093                 return err;
1094         }
1095         for (cidx = 0; cidx < 2; cidx++) {
1096                 int devtype = -1;
1097                 if (pcm->streams[cidx].substream == NULL || pcm->internal)
1098                         continue;
1099                 switch (cidx) {
1100                 case SNDRV_PCM_STREAM_PLAYBACK:
1101                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1102                         break;
1103                 case SNDRV_PCM_STREAM_CAPTURE:
1104                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1105                         break;
1106                 }
1107                 /* register pcm */
1108                 err = snd_register_device(devtype, pcm->card, pcm->device,
1109                                           &snd_pcm_f_ops[cidx], pcm,
1110                                           &pcm->streams[cidx].dev);
1111                 if (err < 0) {
1112                         list_del(&pcm->list);
1113                         mutex_unlock(&register_mutex);
1114                         return err;
1115                 }
1116
1117                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1118                         snd_pcm_timer_init(substream);
1119         }
1120
1121         list_for_each_entry(notify, &snd_pcm_notify_list, list)
1122                 notify->n_register(pcm);
1123
1124         mutex_unlock(&register_mutex);
1125         return 0;
1126 }
1127
1128 static int snd_pcm_dev_disconnect(struct snd_device *device)
1129 {
1130         struct snd_pcm *pcm = device->device_data;
1131         struct snd_pcm_notify *notify;
1132         struct snd_pcm_substream *substream;
1133         int cidx;
1134
1135         mutex_lock(&register_mutex);
1136         if (list_empty(&pcm->list))
1137                 goto unlock;
1138
1139         mutex_lock(&pcm->open_mutex);
1140         wake_up(&pcm->open_wait);
1141         list_del_init(&pcm->list);
1142         for (cidx = 0; cidx < 2; cidx++)
1143                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1144                         snd_pcm_stream_lock_irq(substream);
1145                         if (substream->runtime) {
1146                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1147                                 wake_up(&substream->runtime->sleep);
1148                                 wake_up(&substream->runtime->tsleep);
1149                         }
1150                         snd_pcm_stream_unlock_irq(substream);
1151                 }
1152         list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1153                 notify->n_disconnect(pcm);
1154         }
1155         for (cidx = 0; cidx < 2; cidx++) {
1156                 snd_unregister_device(&pcm->streams[cidx].dev);
1157                 if (pcm->streams[cidx].chmap_kctl) {
1158                         snd_ctl_remove(pcm->card, pcm->streams[cidx].chmap_kctl);
1159                         pcm->streams[cidx].chmap_kctl = NULL;
1160                 }
1161         }
1162         mutex_unlock(&pcm->open_mutex);
1163  unlock:
1164         mutex_unlock(&register_mutex);
1165         return 0;
1166 }
1167
1168 /**
1169  * snd_pcm_notify - Add/remove the notify list
1170  * @notify: PCM notify list
1171  * @nfree: 0 = register, 1 = unregister
1172  *
1173  * This adds the given notifier to the global list so that the callback is
1174  * called for each registered PCM devices.  This exists only for PCM OSS
1175  * emulation, so far.
1176  */
1177 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1178 {
1179         struct snd_pcm *pcm;
1180
1181         if (snd_BUG_ON(!notify ||
1182                        !notify->n_register ||
1183                        !notify->n_unregister ||
1184                        !notify->n_disconnect))
1185                 return -EINVAL;
1186         mutex_lock(&register_mutex);
1187         if (nfree) {
1188                 list_del(&notify->list);
1189                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1190                         notify->n_unregister(pcm);
1191         } else {
1192                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1193                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1194                         notify->n_register(pcm);
1195         }
1196         mutex_unlock(&register_mutex);
1197         return 0;
1198 }
1199 EXPORT_SYMBOL(snd_pcm_notify);
1200
1201 #ifdef CONFIG_PROC_FS
1202 /*
1203  *  Info interface
1204  */
1205
1206 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1207                               struct snd_info_buffer *buffer)
1208 {
1209         struct snd_pcm *pcm;
1210
1211         mutex_lock(&register_mutex);
1212         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1213                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1214                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1215                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1216                         snd_iprintf(buffer, " : playback %i",
1217                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1218                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1219                         snd_iprintf(buffer, " : capture %i",
1220                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1221                 snd_iprintf(buffer, "\n");
1222         }
1223         mutex_unlock(&register_mutex);
1224 }
1225
1226 static struct snd_info_entry *snd_pcm_proc_entry;
1227
1228 static void snd_pcm_proc_init(void)
1229 {
1230         struct snd_info_entry *entry;
1231
1232         if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1233                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1234                 if (snd_info_register(entry) < 0) {
1235                         snd_info_free_entry(entry);
1236                         entry = NULL;
1237                 }
1238         }
1239         snd_pcm_proc_entry = entry;
1240 }
1241
1242 static void snd_pcm_proc_done(void)
1243 {
1244         snd_info_free_entry(snd_pcm_proc_entry);
1245 }
1246
1247 #else /* !CONFIG_PROC_FS */
1248 #define snd_pcm_proc_init()
1249 #define snd_pcm_proc_done()
1250 #endif /* CONFIG_PROC_FS */
1251
1252
1253 /*
1254  *  ENTRY functions
1255  */
1256
1257 static int __init alsa_pcm_init(void)
1258 {
1259         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1260         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1261         snd_pcm_proc_init();
1262         return 0;
1263 }
1264
1265 static void __exit alsa_pcm_exit(void)
1266 {
1267         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1268         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1269         snd_pcm_proc_done();
1270 }
1271
1272 module_init(alsa_pcm_init)
1273 module_exit(alsa_pcm_exit)