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->prefer_pcm_subdevice = 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 };
 220
 221 const char *snd_pcm_format_name(snd_pcm_format_t format)
 222 {
 223         if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
 224                 return "Unknown";
 225         return snd_pcm_format_names[(__force unsigned int)format];
 226 }
 227 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
 228
 229 #ifdef CONFIG_SND_VERBOSE_PROCFS
 230
 231 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
 232 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
 233 #define READY(v) [SNDRV_PCM_READY_##v] = #v
 234 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
 235 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
 236 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
 237 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
 238 #define START(v) [SNDRV_PCM_START_##v] = #v
 239 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
 240
 241 static char *snd_pcm_stream_names[] = {
 242         STREAM(PLAYBACK),
 243         STREAM(CAPTURE),
 244 };
 245
 246 static char *snd_pcm_state_names[] = {
 247         STATE(OPEN),
 248         STATE(SETUP),
 249         STATE(PREPARED),
 250         STATE(RUNNING),
 251         STATE(XRUN),
 252         STATE(DRAINING),
 253         STATE(PAUSED),
 254         STATE(SUSPENDED),
 255 };
 256
 257 static char *snd_pcm_access_names[] = {
 258         ACCESS(MMAP_INTERLEAVED),
 259         ACCESS(MMAP_NONINTERLEAVED),
 260         ACCESS(MMAP_COMPLEX),
 261         ACCESS(RW_INTERLEAVED),
 262         ACCESS(RW_NONINTERLEAVED),
 263 };
 264
 265 static char *snd_pcm_subformat_names[] = {
 266         SUBFORMAT(STD),
 267 };
 268
 269 static char *snd_pcm_tstamp_mode_names[] = {
 270         TSTAMP(NONE),
 271         TSTAMP(ENABLE),
 272 };
 273
 274 static const char *snd_pcm_stream_name(int stream)
 275 {
 276         return snd_pcm_stream_names[stream];
 277 }
 278
 279 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 280 {
 281         return snd_pcm_access_names[(__force int)access];
 282 }
 283
 284 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 285 {
 286         return snd_pcm_subformat_names[(__force int)subformat];
 287 }
 288
 289 static const char *snd_pcm_tstamp_mode_name(int mode)
 290 {
 291         return snd_pcm_tstamp_mode_names[mode];
 292 }
 293
 294 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 295 {
 296         return snd_pcm_state_names[(__force int)state];
 297 }
 298
 299 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 300 #include <linux/soundcard.h>
 301
 302 static const char *snd_pcm_oss_format_name(int format)
 303 {
 304         switch (format) {
 305         case AFMT_MU_LAW:
 306                 return "MU_LAW";
 307         case AFMT_A_LAW:
 308                 return "A_LAW";
 309         case AFMT_IMA_ADPCM:
 310                 return "IMA_ADPCM";
 311         case AFMT_U8:
 312                 return "U8";
 313         case AFMT_S16_LE:
 314                 return "S16_LE";
 315         case AFMT_S16_BE:
 316                 return "S16_BE";
 317         case AFMT_S8:
 318                 return "S8";
 319         case AFMT_U16_LE:
 320                 return "U16_LE";
 321         case AFMT_U16_BE:
 322                 return "U16_BE";
 323         case AFMT_MPEG:
 324                 return "MPEG";
 325         default:
 326                 return "unknown";
 327         }
 328 }
 329 #endif
 330
 331 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 332                                    struct snd_info_buffer *buffer)
 333 {
 334         struct snd_pcm_info *info;
 335         int err;
 336
 337         if (! substream)
 338                 return;
 339
 340         info = kmalloc(sizeof(*info), GFP_KERNEL);
 341         if (! info) {
 342                 pcm_dbg(substream->pcm,
 343                         "snd_pcm_proc_info_read: cannot malloc\n");
 344                 return;
 345         }
 346
 347         err = snd_pcm_info(substream, info);
 348         if (err < 0) {
 349                 snd_iprintf(buffer, "error %d\n", err);
 350                 kfree(info);
 351                 return;
 352         }
 353         snd_iprintf(buffer, "card: %d\n", info->card);
 354         snd_iprintf(buffer, "device: %d\n", info->device);
 355         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 356         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 357         snd_iprintf(buffer, "id: %s\n", info->id);
 358         snd_iprintf(buffer, "name: %s\n", info->name);
 359         snd_iprintf(buffer, "subname: %s\n", info->subname);
 360         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 361         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 362         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 363         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 364         kfree(info);
 365 }
 366
 367 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 368                                           struct snd_info_buffer *buffer)
 369 {
 370         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 371                                buffer);
 372 }
 373
 374 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 375                                              struct snd_info_buffer *buffer)
 376 {
 377         snd_pcm_proc_info_read(entry->private_data, buffer);
 378 }
 379
 380 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 381                                                   struct snd_info_buffer *buffer)
 382 {
 383         struct snd_pcm_substream *substream = entry->private_data;
 384         struct snd_pcm_runtime *runtime;
 385
 386         mutex_lock(&substream->pcm->open_mutex);
 387         runtime = substream->runtime;
 388         if (!runtime) {
 389                 snd_iprintf(buffer, "closed\n");
 390                 goto unlock;
 391         }
 392         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 393                 snd_iprintf(buffer, "no setup\n");
 394                 goto unlock;
 395         }
 396         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 397         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 398         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 399         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 400         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 401         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 402         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 403 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 404         if (substream->oss.oss) {
 405                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 406                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 407                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 408                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 409                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 410                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 411         }
 412 #endif
 413  unlock:
 414         mutex_unlock(&substream->pcm->open_mutex);
 415 }
 416
 417 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 418                                                   struct snd_info_buffer *buffer)
 419 {
 420         struct snd_pcm_substream *substream = entry->private_data;
 421         struct snd_pcm_runtime *runtime;
 422
 423         mutex_lock(&substream->pcm->open_mutex);
 424         runtime = substream->runtime;
 425         if (!runtime) {
 426                 snd_iprintf(buffer, "closed\n");
 427                 goto unlock;
 428         }
 429         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 430                 snd_iprintf(buffer, "no setup\n");
 431                 goto unlock;
 432         }
 433         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 434         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 435         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 436         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 437         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 438         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 439         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 440         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 441  unlock:
 442         mutex_unlock(&substream->pcm->open_mutex);
 443 }
 444
 445 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 446                                                struct snd_info_buffer *buffer)
 447 {
 448         struct snd_pcm_substream *substream = entry->private_data;
 449         struct snd_pcm_runtime *runtime;
 450         struct snd_pcm_status status;
 451         int err;
 452
 453         mutex_lock(&substream->pcm->open_mutex);
 454         runtime = substream->runtime;
 455         if (!runtime) {
 456                 snd_iprintf(buffer, "closed\n");
 457                 goto unlock;
 458         }
 459         memset(&status, 0, sizeof(status));
 460         err = snd_pcm_status(substream, &status);
 461         if (err < 0) {
 462                 snd_iprintf(buffer, "error %d\n", err);
 463                 goto unlock;
 464         }
 465         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 466         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 467         snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
 468                 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
 469         snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
 470                 status.tstamp.tv_sec, status.tstamp.tv_nsec);
 471         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 472         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 473         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 474         snd_iprintf(buffer, "-----\n");
 475         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 476         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 477  unlock:
 478         mutex_unlock(&substream->pcm->open_mutex);
 479 }
 480
 481 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 482 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 483                                     struct snd_info_buffer *buffer)
 484 {
 485         struct snd_pcm_str *pstr = entry->private_data;
 486         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 487 }
 488
 489 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 490                                      struct snd_info_buffer *buffer)
 491 {
 492         struct snd_pcm_str *pstr = entry->private_data;
 493         char line[64];
 494         if (!snd_info_get_line(buffer, line, sizeof(line)))
 495                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 496 }
 497 #endif
 498
 499 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 500 {
 501         struct snd_pcm *pcm = pstr->pcm;
 502         struct snd_info_entry *entry;
 503         char name[16];
 504
 505         sprintf(name, "pcm%i%c", pcm->device,
 506                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 507         if ((entry = snd_info_create_card_entry(pcm->card, name, pcm->card->proc_root)) == NULL)
 508                 return -ENOMEM;
 509         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 510         if (snd_info_register(entry) < 0) {
 511                 snd_info_free_entry(entry);
 512                 return -ENOMEM;
 513         }
 514         pstr->proc_root = entry;
 515
 516         if ((entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root)) != NULL) {
 517                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 518                 if (snd_info_register(entry) < 0) {
 519                         snd_info_free_entry(entry);
 520                         entry = NULL;
 521                 }
 522         }
 523         pstr->proc_info_entry = entry;
 524
 525 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 526         if ((entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 527                                                 pstr->proc_root)) != NULL) {
 528                 entry->c.text.read = snd_pcm_xrun_debug_read;
 529                 entry->c.text.write = snd_pcm_xrun_debug_write;
 530                 entry->mode |= S_IWUSR;
 531                 entry->private_data = pstr;
 532                 if (snd_info_register(entry) < 0) {
 533                         snd_info_free_entry(entry);
 534                         entry = NULL;
 535                 }
 536         }
 537         pstr->proc_xrun_debug_entry = entry;
 538 #endif
 539         return 0;
 540 }
 541
 542 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 543 {
 544 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 545         snd_info_free_entry(pstr->proc_xrun_debug_entry);
 546         pstr->proc_xrun_debug_entry = NULL;
 547 #endif
 548         snd_info_free_entry(pstr->proc_info_entry);
 549         pstr->proc_info_entry = NULL;
 550         snd_info_free_entry(pstr->proc_root);
 551         pstr->proc_root = NULL;
 552         return 0;
 553 }
 554
 555 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 556 {
 557         struct snd_info_entry *entry;
 558         struct snd_card *card;
 559         char name[16];
 560
 561         card = substream->pcm->card;
 562
 563         sprintf(name, "sub%i", substream->number);
 564         if ((entry = snd_info_create_card_entry(card, name, substream->pstr->proc_root)) == NULL)
 565                 return -ENOMEM;
 566         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 567         if (snd_info_register(entry) < 0) {
 568                 snd_info_free_entry(entry);
 569                 return -ENOMEM;
 570         }
 571         substream->proc_root = entry;
 572
 573         if ((entry = snd_info_create_card_entry(card, "info", substream->proc_root)) != NULL) {
 574                 snd_info_set_text_ops(entry, substream,
 575                                       snd_pcm_substream_proc_info_read);
 576                 if (snd_info_register(entry) < 0) {
 577                         snd_info_free_entry(entry);
 578                         entry = NULL;
 579                 }
 580         }
 581         substream->proc_info_entry = entry;
 582
 583         if ((entry = snd_info_create_card_entry(card, "hw_params", substream->proc_root)) != NULL) {
 584                 snd_info_set_text_ops(entry, substream,
 585                                       snd_pcm_substream_proc_hw_params_read);
 586                 if (snd_info_register(entry) < 0) {
 587                         snd_info_free_entry(entry);
 588                         entry = NULL;
 589                 }
 590         }
 591         substream->proc_hw_params_entry = entry;
 592
 593         if ((entry = snd_info_create_card_entry(card, "sw_params", substream->proc_root)) != NULL) {
 594                 snd_info_set_text_ops(entry, substream,
 595                                       snd_pcm_substream_proc_sw_params_read);
 596                 if (snd_info_register(entry) < 0) {
 597                         snd_info_free_entry(entry);
 598                         entry = NULL;
 599                 }
 600         }
 601         substream->proc_sw_params_entry = entry;
 602
 603         if ((entry = snd_info_create_card_entry(card, "status", substream->proc_root)) != NULL) {
 604                 snd_info_set_text_ops(entry, substream,
 605                                       snd_pcm_substream_proc_status_read);
 606                 if (snd_info_register(entry) < 0) {
 607                         snd_info_free_entry(entry);
 608                         entry = NULL;
 609                 }
 610         }
 611         substream->proc_status_entry = entry;
 612
 613         return 0;
 614 }
 615
 616 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 617 {
 618         snd_info_free_entry(substream->proc_info_entry);
 619         substream->proc_info_entry = NULL;
 620         snd_info_free_entry(substream->proc_hw_params_entry);
 621         substream->proc_hw_params_entry = NULL;
 622         snd_info_free_entry(substream->proc_sw_params_entry);
 623         substream->proc_sw_params_entry = NULL;
 624         snd_info_free_entry(substream->proc_status_entry);
 625         substream->proc_status_entry = NULL;
 626         snd_info_free_entry(substream->proc_root);
 627         substream->proc_root = NULL;
 628         return 0;
 629 }
 630 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 631 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 632 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 633 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 634 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
 635 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 636
 637 /**
 638  * snd_pcm_new_stream - create a new PCM stream
 639  * @pcm: the pcm instance
 640  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 641  * @substream_count: the number of substreams
 642  *
 643  * Creates a new stream for the pcm.
 644  * The corresponding stream on the pcm must have been empty before
 645  * calling this, i.e. zero must be given to the argument of
 646  * snd_pcm_new().
 647  *
 648  * Return: Zero if successful, or a negative error code on failure.
 649  */
 650 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 651 {
 652         int idx, err;
 653         struct snd_pcm_str *pstr = &pcm->streams[stream];
 654         struct snd_pcm_substream *substream, *prev;
 655
 656 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 657         mutex_init(&pstr->oss.setup_mutex);
 658 #endif
 659         pstr->stream = stream;
 660         pstr->pcm = pcm;
 661         pstr->substream_count = substream_count;
 662         if (substream_count > 0 && !pcm->internal) {
 663                 err = snd_pcm_stream_proc_init(pstr);
 664                 if (err < 0) {
 665                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 666                         return err;
 667                 }
 668         }
 669         prev = NULL;
 670         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 671                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 672                 if (substream == NULL) {
 673                         pcm_err(pcm, "Cannot allocate PCM substream\n");
 674                         return -ENOMEM;
 675                 }
 676                 substream->pcm = pcm;
 677                 substream->pstr = pstr;
 678                 substream->number = idx;
 679                 substream->stream = stream;
 680                 sprintf(substream->name, "subdevice #%i", idx);
 681                 substream->buffer_bytes_max = UINT_MAX;
 682                 if (prev == NULL)
 683                         pstr->substream = substream;
 684                 else
 685                         prev->next = substream;
 686
 687                 if (!pcm->internal) {
 688                         err = snd_pcm_substream_proc_init(substream);
 689                         if (err < 0) {
 690                                 pcm_err(pcm,
 691                                         "Error in snd_pcm_stream_proc_init\n");
 692                                 if (prev == NULL)
 693                                         pstr->substream = NULL;
 694                                 else
 695                                         prev->next = NULL;
 696                                 kfree(substream);
 697                                 return err;
 698                         }
 699                 }
 700                 substream->group = &substream->self_group;
 701                 spin_lock_init(&substream->self_group.lock);
 702                 mutex_init(&substream->self_group.mutex);
 703                 INIT_LIST_HEAD(&substream->self_group.substreams);
 704                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 705                 atomic_set(&substream->mmap_count, 0);
 706                 prev = substream;
 707         }
 708         return 0;
 709 }
 710
 711 EXPORT_SYMBOL(snd_pcm_new_stream);
 712
 713 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 714                 int playback_count, int capture_count, bool internal,
 715                 struct snd_pcm **rpcm)
 716 {
 717         struct snd_pcm *pcm;
 718         int err;
 719         static struct snd_device_ops ops = {
 720                 .dev_free = snd_pcm_dev_free,
 721                 .dev_register = snd_pcm_dev_register,
 722                 .dev_disconnect = snd_pcm_dev_disconnect,
 723         };
 724
 725         if (snd_BUG_ON(!card))
 726                 return -ENXIO;
 727         if (rpcm)
 728                 *rpcm = NULL;
 729         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 730         if (pcm == NULL) {
 731                 dev_err(card->dev, "Cannot allocate PCM\n");
 732                 return -ENOMEM;
 733         }
 734         pcm->card = card;
 735         pcm->device = device;
 736         pcm->internal = internal;
 737         if (id)
 738                 strlcpy(pcm->id, id, sizeof(pcm->id));
 739         if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) {
 740                 snd_pcm_free(pcm);
 741                 return err;
 742         }
 743         if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count)) < 0) {
 744                 snd_pcm_free(pcm);
 745                 return err;
 746         }
 747         mutex_init(&pcm->open_mutex);
 748         init_waitqueue_head(&pcm->open_wait);
 749         if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) {
 750                 snd_pcm_free(pcm);
 751                 return err;
 752         }
 753         if (rpcm)
 754                 *rpcm = pcm;
 755         return 0;
 756 }
 757
 758 /**
 759  * snd_pcm_new - create a new PCM instance
 760  * @card: the card instance
 761  * @id: the id string
 762  * @device: the device index (zero based)
 763  * @playback_count: the number of substreams for playback
 764  * @capture_count: the number of substreams for capture
 765  * @rpcm: the pointer to store the new pcm instance
 766  *
 767  * Creates a new PCM instance.
 768  *
 769  * The pcm operators have to be set afterwards to the new instance
 770  * via snd_pcm_set_ops().
 771  *
 772  * Return: Zero if successful, or a negative error code on failure.
 773  */
 774 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 775                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 776 {
 777         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 778                         false, rpcm);
 779 }
 780 EXPORT_SYMBOL(snd_pcm_new);
 781
 782 /**
 783  * snd_pcm_new_internal - create a new internal PCM instance
 784  * @card: the card instance
 785  * @id: the id string
 786  * @device: the device index (zero based - shared with normal PCMs)
 787  * @playback_count: the number of substreams for playback
 788  * @capture_count: the number of substreams for capture
 789  * @rpcm: the pointer to store the new pcm instance
 790  *
 791  * Creates a new internal PCM instance with no userspace device or procfs
 792  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 793  * will only be used internally by kernel drivers. i.e. it cannot be opened
 794  * by userspace. It provides existing ASoC components drivers with a substream
 795  * and access to any private data.
 796  *
 797  * The pcm operators have to be set afterwards to the new instance
 798  * via snd_pcm_set_ops().
 799  *
 800  * Return: Zero if successful, or a negative error code on failure.
 801  */
 802 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 803         int playback_count, int capture_count,
 804         struct snd_pcm **rpcm)
 805 {
 806         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 807                         true, rpcm);
 808 }
 809 EXPORT_SYMBOL(snd_pcm_new_internal);
 810
 811 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 812 {
 813         struct snd_pcm_substream *substream, *substream_next;
 814 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 815         struct snd_pcm_oss_setup *setup, *setupn;
 816 #endif
 817         substream = pstr->substream;
 818         while (substream) {
 819                 substream_next = substream->next;
 820                 snd_pcm_timer_done(substream);
 821                 snd_pcm_substream_proc_done(substream);
 822                 kfree(substream);
 823                 substream = substream_next;
 824         }
 825         snd_pcm_stream_proc_done(pstr);
 826 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 827         for (setup = pstr->oss.setup_list; setup; setup = setupn) {
 828                 setupn = setup->next;
 829                 kfree(setup->task_name);
 830                 kfree(setup);
 831         }
 832 #endif
 833 }
 834
 835 static int snd_pcm_free(struct snd_pcm *pcm)
 836 {
 837         struct snd_pcm_notify *notify;
 838
 839         if (!pcm)
 840                 return 0;
 841         list_for_each_entry(notify, &snd_pcm_notify_list, list) {
 842                 notify->n_unregister(pcm);
 843         }
 844         if (pcm->private_free)
 845                 pcm->private_free(pcm);
 846         snd_pcm_lib_preallocate_free_for_all(pcm);
 847         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
 848         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
 849         kfree(pcm);
 850         return 0;
 851 }
 852
 853 static int snd_pcm_dev_free(struct snd_device *device)
 854 {
 855         struct snd_pcm *pcm = device->device_data;
 856         return snd_pcm_free(pcm);
 857 }
 858
 859 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 860                              struct file *file,
 861                              struct snd_pcm_substream **rsubstream)
 862 {
 863         struct snd_pcm_str * pstr;
 864         struct snd_pcm_substream *substream;
 865         struct snd_pcm_runtime *runtime;
 866         struct snd_ctl_file *kctl;
 867         struct snd_card *card;
 868         int prefer_subdevice = -1;
 869         size_t size;
 870
 871         if (snd_BUG_ON(!pcm || !rsubstream))
 872                 return -ENXIO;
 873         *rsubstream = NULL;
 874         pstr = &pcm->streams[stream];
 875         if (pstr->substream == NULL || pstr->substream_count == 0)
 876                 return -ENODEV;
 877
 878         card = pcm->card;
 879         read_lock(&card->ctl_files_rwlock);
 880         list_for_each_entry(kctl, &card->ctl_files, list) {
 881                 if (kctl->pid == task_pid(current)) {
 882                         prefer_subdevice = kctl->prefer_pcm_subdevice;
 883                         if (prefer_subdevice != -1)
 884                                 break;
 885                 }
 886         }
 887         read_unlock(&card->ctl_files_rwlock);
 888
 889         switch (stream) {
 890         case SNDRV_PCM_STREAM_PLAYBACK:
 891                 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 892                         for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next) {
 893                                 if (SUBSTREAM_BUSY(substream))
 894                                         return -EAGAIN;
 895                         }
 896                 }
 897                 break;
 898         case SNDRV_PCM_STREAM_CAPTURE:
 899                 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 900                         for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next) {
 901                                 if (SUBSTREAM_BUSY(substream))
 902                                         return -EAGAIN;
 903                         }
 904                 }
 905                 break;
 906         default:
 907                 return -EINVAL;
 908         }
 909
 910         if (file->f_flags & O_APPEND) {
 911                 if (prefer_subdevice < 0) {
 912                         if (pstr->substream_count > 1)
 913                                 return -EINVAL; /* must be unique */
 914                         substream = pstr->substream;
 915                 } else {
 916                         for (substream = pstr->substream; substream;
 917                              substream = substream->next)
 918                                 if (substream->number == prefer_subdevice)
 919                                         break;
 920                 }
 921                 if (! substream)
 922                         return -ENODEV;
 923                 if (! SUBSTREAM_BUSY(substream))
 924                         return -EBADFD;
 925                 substream->ref_count++;
 926                 *rsubstream = substream;
 927                 return 0;
 928         }
 929
 930         if (prefer_subdevice >= 0) {
 931                 for (substream = pstr->substream; substream; substream = substream->next)
 932                         if (!SUBSTREAM_BUSY(substream) && substream->number == prefer_subdevice)
 933                                 goto __ok;
 934         }
 935         for (substream = pstr->substream; substream; substream = substream->next)
 936                 if (!SUBSTREAM_BUSY(substream))
 937                         break;
 938       __ok:
 939         if (substream == NULL)
 940                 return -EAGAIN;
 941
 942         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 943         if (runtime == NULL)
 944                 return -ENOMEM;
 945
 946         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
 947         runtime->status = snd_malloc_pages(size, GFP_KERNEL);
 948         if (runtime->status == NULL) {
 949                 kfree(runtime);
 950                 return -ENOMEM;
 951         }
 952         memset((void*)runtime->status, 0, size);
 953
 954         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
 955         runtime->control = snd_malloc_pages(size, GFP_KERNEL);
 956         if (runtime->control == NULL) {
 957                 snd_free_pages((void*)runtime->status,
 958                                PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
 959                 kfree(runtime);
 960                 return -ENOMEM;
 961         }
 962         memset((void*)runtime->control, 0, size);
 963
 964         init_waitqueue_head(&runtime->sleep);
 965         init_waitqueue_head(&runtime->tsleep);
 966
 967         runtime->status->state = SNDRV_PCM_STATE_OPEN;
 968
 969         substream->runtime = runtime;
 970         substream->private_data = pcm->private_data;
 971         substream->ref_count = 1;
 972         substream->f_flags = file->f_flags;
 973         substream->pid = get_pid(task_pid(current));
 974         pstr->substream_opened++;
 975         *rsubstream = substream;
 976         return 0;
 977 }
 978
 979 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
 980 {
 981         struct snd_pcm_runtime *runtime;
 982
 983         if (PCM_RUNTIME_CHECK(substream))
 984                 return;
 985         runtime = substream->runtime;
 986         if (runtime->private_free != NULL)
 987                 runtime->private_free(runtime);
 988         snd_free_pages((void*)runtime->status,
 989                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
 990         snd_free_pages((void*)runtime->control,
 991                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
 992         kfree(runtime->hw_constraints.rules);
 993 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 994         kfree(runtime->hwptr_log);
 995 #endif
 996         kfree(runtime);
 997         substream->runtime = NULL;
 998         put_pid(substream->pid);
 999         substream->pid = NULL;
1000         substream->pstr->substream_opened--;
1001 }
1002
1003 static ssize_t show_pcm_class(struct device *dev,
1004                               struct device_attribute *attr, char *buf)
1005 {
1006         struct snd_pcm *pcm;
1007         const char *str;
1008         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1009                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1010                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1011                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1012                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1013         };
1014
1015         if (! (pcm = dev_get_drvdata(dev)) ||
1016             pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1017                 str = "none";
1018         else
1019                 str = strs[pcm->dev_class];
1020         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1021 }
1022
1023 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1024 static struct attribute *pcm_dev_attrs[] = {
1025         &dev_attr_pcm_class.attr,
1026         NULL
1027 };
1028
1029 static struct attribute_group pcm_dev_attr_group = {
1030         .attrs  = pcm_dev_attrs,
1031 };
1032
1033 static const struct attribute_group *pcm_dev_attr_groups[] = {
1034         &pcm_dev_attr_group,
1035         NULL
1036 };
1037
1038 static int snd_pcm_dev_register(struct snd_device *device)
1039 {
1040         int cidx, err;
1041         struct snd_pcm_substream *substream;
1042         struct snd_pcm_notify *notify;
1043         char str[16];
1044         struct snd_pcm *pcm;
1045         struct device *dev;
1046
1047         if (snd_BUG_ON(!device || !device->device_data))
1048                 return -ENXIO;
1049         pcm = device->device_data;
1050         mutex_lock(&register_mutex);
1051         err = snd_pcm_add(pcm);
1052         if (err) {
1053                 mutex_unlock(&register_mutex);
1054                 return err;
1055         }
1056         for (cidx = 0; cidx < 2; cidx++) {
1057                 int devtype = -1;
1058                 if (pcm->streams[cidx].substream == NULL || pcm->internal)
1059                         continue;
1060                 switch (cidx) {
1061                 case SNDRV_PCM_STREAM_PLAYBACK:
1062                         sprintf(str, "pcmC%iD%ip", pcm->card->number, pcm->device);
1063                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1064                         break;
1065                 case SNDRV_PCM_STREAM_CAPTURE:
1066                         sprintf(str, "pcmC%iD%ic", pcm->card->number, pcm->device);
1067                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1068                         break;
1069                 }
1070                 /* device pointer to use, pcm->dev takes precedence if
1071                  * it is assigned, otherwise fall back to card's device
1072                  * if possible */
1073                 dev = pcm->dev;
1074                 if (!dev)
1075                         dev = snd_card_get_device_link(pcm->card);
1076                 /* register pcm */
1077                 err = snd_register_device_for_dev(devtype, pcm->card,
1078                                                   pcm->device,
1079                                                   &snd_pcm_f_ops[cidx],
1080                                                   pcm, str, dev);
1081                 if (err < 0) {
1082                         list_del(&pcm->list);
1083                         mutex_unlock(&register_mutex);
1084                         return err;
1085                 }
1086
1087                 dev = snd_get_device(devtype, pcm->card, pcm->device);
1088                 if (dev) {
1089                         err = sysfs_create_groups(&dev->kobj,
1090                                                   pcm_dev_attr_groups);
1091                         if (err < 0)
1092                                 dev_warn(dev,
1093                                          "pcm %d:%d: cannot create sysfs groups\n",
1094                                          pcm->card->number, pcm->device);
1095                         put_device(dev);
1096                 }
1097
1098                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1099                         snd_pcm_timer_init(substream);
1100         }
1101
1102         list_for_each_entry(notify, &snd_pcm_notify_list, list)
1103                 notify->n_register(pcm);
1104
1105         mutex_unlock(&register_mutex);
1106         return 0;
1107 }
1108
1109 static int snd_pcm_dev_disconnect(struct snd_device *device)
1110 {
1111         struct snd_pcm *pcm = device->device_data;
1112         struct snd_pcm_notify *notify;
1113         struct snd_pcm_substream *substream;
1114         int cidx, devtype;
1115
1116         mutex_lock(&register_mutex);
1117         if (list_empty(&pcm->list))
1118                 goto unlock;
1119
1120         mutex_lock(&pcm->open_mutex);
1121         wake_up(&pcm->open_wait);
1122         list_del_init(&pcm->list);
1123         for (cidx = 0; cidx < 2; cidx++)
1124                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1125                         snd_pcm_stream_lock_irq(substream);
1126                         if (substream->runtime) {
1127                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1128                                 wake_up(&substream->runtime->sleep);
1129                                 wake_up(&substream->runtime->tsleep);
1130                         }
1131                         snd_pcm_stream_unlock_irq(substream);
1132                 }
1133         list_for_each_entry(notify, &snd_pcm_notify_list, list) {
1134                 notify->n_disconnect(pcm);
1135         }
1136         for (cidx = 0; cidx < 2; cidx++) {
1137                 devtype = -1;
1138                 switch (cidx) {
1139                 case SNDRV_PCM_STREAM_PLAYBACK:
1140                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1141                         break;
1142                 case SNDRV_PCM_STREAM_CAPTURE:
1143                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1144                         break;
1145                 }
1146                 snd_unregister_device(devtype, pcm->card, pcm->device);
1147                 if (pcm->streams[cidx].chmap_kctl) {
1148                         snd_ctl_remove(pcm->card, pcm->streams[cidx].chmap_kctl);
1149                         pcm->streams[cidx].chmap_kctl = NULL;
1150                 }
1151         }
1152         mutex_unlock(&pcm->open_mutex);
1153  unlock:
1154         mutex_unlock(&register_mutex);
1155         return 0;
1156 }
1157
1158 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1159 {
1160         struct snd_pcm *pcm;
1161
1162         if (snd_BUG_ON(!notify ||
1163                        !notify->n_register ||
1164                        !notify->n_unregister ||
1165                        !notify->n_disconnect))
1166                 return -EINVAL;
1167         mutex_lock(&register_mutex);
1168         if (nfree) {
1169                 list_del(&notify->list);
1170                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1171                         notify->n_unregister(pcm);
1172         } else {
1173                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1174                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1175                         notify->n_register(pcm);
1176         }
1177         mutex_unlock(&register_mutex);
1178         return 0;
1179 }
1180
1181 EXPORT_SYMBOL(snd_pcm_notify);
1182
1183 #ifdef CONFIG_PROC_FS
1184 /*
1185  *  Info interface
1186  */
1187
1188 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1189                               struct snd_info_buffer *buffer)
1190 {
1191         struct snd_pcm *pcm;
1192
1193         mutex_lock(&register_mutex);
1194         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1195                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1196                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1197                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1198                         snd_iprintf(buffer, " : playback %i",
1199                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1200                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1201                         snd_iprintf(buffer, " : capture %i",
1202                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1203                 snd_iprintf(buffer, "\n");
1204         }
1205         mutex_unlock(&register_mutex);
1206 }
1207
1208 static struct snd_info_entry *snd_pcm_proc_entry;
1209
1210 static void snd_pcm_proc_init(void)
1211 {
1212         struct snd_info_entry *entry;
1213
1214         if ((entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL)) != NULL) {
1215                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1216                 if (snd_info_register(entry) < 0) {
1217                         snd_info_free_entry(entry);
1218                         entry = NULL;
1219                 }
1220         }
1221         snd_pcm_proc_entry = entry;
1222 }
1223
1224 static void snd_pcm_proc_done(void)
1225 {
1226         snd_info_free_entry(snd_pcm_proc_entry);
1227 }
1228
1229 #else /* !CONFIG_PROC_FS */
1230 #define snd_pcm_proc_init()
1231 #define snd_pcm_proc_done()
1232 #endif /* CONFIG_PROC_FS */
1233
1234
1235 /*
1236  *  ENTRY functions
1237  */
1238
1239 static int __init alsa_pcm_init(void)
1240 {
1241         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1242         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1243         snd_pcm_proc_init();
1244         return 0;
1245 }
1246
1247 static void __exit alsa_pcm_exit(void)
1248 {
1249         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1250         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1251         snd_pcm_proc_done();
1252 }
1253
1254 module_init(alsa_pcm_init)
1255 module_exit(alsa_pcm_exit)