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 #include "pcm_local.h"
  35
  36 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
  37 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
  38 MODULE_LICENSE("GPL");
  39
  40 static LIST_HEAD(snd_pcm_devices);
  41 static DEFINE_MUTEX(register_mutex);
  42 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
  43 static LIST_HEAD(snd_pcm_notify_list);
  44 #endif
  45
  46 static int snd_pcm_free(struct snd_pcm *pcm);
  47 static int snd_pcm_dev_free(struct snd_device *device);
  48 static int snd_pcm_dev_register(struct snd_device *device);
  49 static int snd_pcm_dev_disconnect(struct snd_device *device);
  50
  51 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
  52 {
  53         struct snd_pcm *pcm;
  54
  55         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  56                 if (pcm->card == card && pcm->device == device)
  57                         return pcm;
  58         }
  59         return NULL;
  60 }
  61
  62 static int snd_pcm_next(struct snd_card *card, int device)
  63 {
  64         struct snd_pcm *pcm;
  65
  66         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  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         if (newpcm->internal)
  80                 return 0;
  81
  82         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  83                 if (pcm->card == newpcm->card && pcm->device == newpcm->device)
  84                         return -EBUSY;
  85                 if (pcm->card->number > newpcm->card->number ||
  86                                 (pcm->card == newpcm->card &&
  87                                 pcm->device > newpcm->device)) {
  88                         list_add(&newpcm->list, pcm->list.prev);
  89                         return 0;
  90                 }
  91         }
  92         list_add_tail(&newpcm->list, &snd_pcm_devices);
  93         return 0;
  94 }
  95
  96 static int snd_pcm_control_ioctl(struct snd_card *card,
  97                                  struct snd_ctl_file *control,
  98                                  unsigned int cmd, unsigned long arg)
  99 {
 100         switch (cmd) {
 101         case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
 102                 {
 103                         int device;
 104
 105                         if (get_user(device, (int __user *)arg))
 106                                 return -EFAULT;
 107                         mutex_lock(&register_mutex);
 108                         device = snd_pcm_next(card, device);
 109                         mutex_unlock(&register_mutex);
 110                         if (put_user(device, (int __user *)arg))
 111                                 return -EFAULT;
 112                         return 0;
 113                 }
 114         case SNDRV_CTL_IOCTL_PCM_INFO:
 115                 {
 116                         struct snd_pcm_info __user *info;
 117                         unsigned int device, subdevice;
 118                         int stream;
 119                         struct snd_pcm *pcm;
 120                         struct snd_pcm_str *pstr;
 121                         struct snd_pcm_substream *substream;
 122                         int err;
 123
 124                         info = (struct snd_pcm_info __user *)arg;
 125                         if (get_user(device, &info->device))
 126                                 return -EFAULT;
 127                         if (get_user(stream, &info->stream))
 128                                 return -EFAULT;
 129                         if (stream < 0 || stream > 1)
 130                                 return -EINVAL;
 131                         if (get_user(subdevice, &info->subdevice))
 132                                 return -EFAULT;
 133                         mutex_lock(&register_mutex);
 134                         pcm = snd_pcm_get(card, device);
 135                         if (pcm == NULL) {
 136                                 err = -ENXIO;
 137                                 goto _error;
 138                         }
 139                         pstr = &pcm->streams[stream];
 140                         if (pstr->substream_count == 0) {
 141                                 err = -ENOENT;
 142                                 goto _error;
 143                         }
 144                         if (subdevice >= pstr->substream_count) {
 145                                 err = -ENXIO;
 146                                 goto _error;
 147                         }
 148                         for (substream = pstr->substream; substream;
 149                              substream = substream->next)
 150                                 if (substream->number == (int)subdevice)
 151                                         break;
 152                         if (substream == NULL) {
 153                                 err = -ENXIO;
 154                                 goto _error;
 155                         }
 156                         mutex_lock(&pcm->open_mutex);
 157                         err = snd_pcm_info_user(substream, info);
 158                         mutex_unlock(&pcm->open_mutex);
 159                 _error:
 160                         mutex_unlock(&register_mutex);
 161                         return err;
 162                 }
 163         case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
 164                 {
 165                         int val;
 166
 167                         if (get_user(val, (int __user *)arg))
 168                                 return -EFAULT;
 169                         control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
 170                         return 0;
 171                 }
 172         }
 173         return -ENOIOCTLCMD;
 174 }
 175
 176 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
 177
 178 static char *snd_pcm_format_names[] = {
 179         FORMAT(S8),
 180         FORMAT(U8),
 181         FORMAT(S16_LE),
 182         FORMAT(S16_BE),
 183         FORMAT(U16_LE),
 184         FORMAT(U16_BE),
 185         FORMAT(S24_LE),
 186         FORMAT(S24_BE),
 187         FORMAT(U24_LE),
 188         FORMAT(U24_BE),
 189         FORMAT(S32_LE),
 190         FORMAT(S32_BE),
 191         FORMAT(U32_LE),
 192         FORMAT(U32_BE),
 193         FORMAT(FLOAT_LE),
 194         FORMAT(FLOAT_BE),
 195         FORMAT(FLOAT64_LE),
 196         FORMAT(FLOAT64_BE),
 197         FORMAT(IEC958_SUBFRAME_LE),
 198         FORMAT(IEC958_SUBFRAME_BE),
 199         FORMAT(MU_LAW),
 200         FORMAT(A_LAW),
 201         FORMAT(IMA_ADPCM),
 202         FORMAT(MPEG),
 203         FORMAT(GSM),
 204         FORMAT(SPECIAL),
 205         FORMAT(S24_3LE),
 206         FORMAT(S24_3BE),
 207         FORMAT(U24_3LE),
 208         FORMAT(U24_3BE),
 209         FORMAT(S20_3LE),
 210         FORMAT(S20_3BE),
 211         FORMAT(U20_3LE),
 212         FORMAT(U20_3BE),
 213         FORMAT(S18_3LE),
 214         FORMAT(S18_3BE),
 215         FORMAT(U18_3LE),
 216         FORMAT(U18_3BE),
 217         FORMAT(G723_24),
 218         FORMAT(G723_24_1B),
 219         FORMAT(G723_40),
 220         FORMAT(G723_40_1B),
 221         FORMAT(DSD_U8),
 222         FORMAT(DSD_U16_LE),
 223         FORMAT(DSD_U32_LE),
 224         FORMAT(DSD_U16_BE),
 225         FORMAT(DSD_U32_BE),
 226 };
 227
 228 /**
 229  * snd_pcm_format_name - Return a name string for the given PCM format
 230  * @format: PCM format
 231  */
 232 const char *snd_pcm_format_name(snd_pcm_format_t format)
 233 {
 234         if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
 235                 return "Unknown";
 236         return snd_pcm_format_names[(__force unsigned int)format];
 237 }
 238 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
 239
 240 #ifdef CONFIG_SND_VERBOSE_PROCFS
 241
 242 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
 243 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
 244 #define READY(v) [SNDRV_PCM_READY_##v] = #v
 245 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
 246 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
 247 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
 248 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
 249 #define START(v) [SNDRV_PCM_START_##v] = #v
 250 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
 251
 252 static char *snd_pcm_stream_names[] = {
 253         STREAM(PLAYBACK),
 254         STREAM(CAPTURE),
 255 };
 256
 257 static char *snd_pcm_state_names[] = {
 258         STATE(OPEN),
 259         STATE(SETUP),
 260         STATE(PREPARED),
 261         STATE(RUNNING),
 262         STATE(XRUN),
 263         STATE(DRAINING),
 264         STATE(PAUSED),
 265         STATE(SUSPENDED),
 266 };
 267
 268 static char *snd_pcm_access_names[] = {
 269         ACCESS(MMAP_INTERLEAVED),
 270         ACCESS(MMAP_NONINTERLEAVED),
 271         ACCESS(MMAP_COMPLEX),
 272         ACCESS(RW_INTERLEAVED),
 273         ACCESS(RW_NONINTERLEAVED),
 274 };
 275
 276 static char *snd_pcm_subformat_names[] = {
 277         SUBFORMAT(STD),
 278 };
 279
 280 static char *snd_pcm_tstamp_mode_names[] = {
 281         TSTAMP(NONE),
 282         TSTAMP(ENABLE),
 283 };
 284
 285 static const char *snd_pcm_stream_name(int stream)
 286 {
 287         return snd_pcm_stream_names[stream];
 288 }
 289
 290 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 291 {
 292         return snd_pcm_access_names[(__force int)access];
 293 }
 294
 295 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 296 {
 297         return snd_pcm_subformat_names[(__force int)subformat];
 298 }
 299
 300 static const char *snd_pcm_tstamp_mode_name(int mode)
 301 {
 302         return snd_pcm_tstamp_mode_names[mode];
 303 }
 304
 305 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 306 {
 307         return snd_pcm_state_names[(__force int)state];
 308 }
 309
 310 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 311 #include <linux/soundcard.h>
 312
 313 static const char *snd_pcm_oss_format_name(int format)
 314 {
 315         switch (format) {
 316         case AFMT_MU_LAW:
 317                 return "MU_LAW";
 318         case AFMT_A_LAW:
 319                 return "A_LAW";
 320         case AFMT_IMA_ADPCM:
 321                 return "IMA_ADPCM";
 322         case AFMT_U8:
 323                 return "U8";
 324         case AFMT_S16_LE:
 325                 return "S16_LE";
 326         case AFMT_S16_BE:
 327                 return "S16_BE";
 328         case AFMT_S8:
 329                 return "S8";
 330         case AFMT_U16_LE:
 331                 return "U16_LE";
 332         case AFMT_U16_BE:
 333                 return "U16_BE";
 334         case AFMT_MPEG:
 335                 return "MPEG";
 336         default:
 337                 return "unknown";
 338         }
 339 }
 340 #endif
 341
 342 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 343                                    struct snd_info_buffer *buffer)
 344 {
 345         struct snd_pcm_info *info;
 346         int err;
 347
 348         if (! substream)
 349                 return;
 350
 351         info = kmalloc(sizeof(*info), GFP_KERNEL);
 352         if (!info)
 353                 return;
 354
 355         err = snd_pcm_info(substream, info);
 356         if (err < 0) {
 357                 snd_iprintf(buffer, "error %d\n", err);
 358                 kfree(info);
 359                 return;
 360         }
 361         snd_iprintf(buffer, "card: %d\n", info->card);
 362         snd_iprintf(buffer, "device: %d\n", info->device);
 363         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 364         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 365         snd_iprintf(buffer, "id: %s\n", info->id);
 366         snd_iprintf(buffer, "name: %s\n", info->name);
 367         snd_iprintf(buffer, "subname: %s\n", info->subname);
 368         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 369         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 370         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 371         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 372         kfree(info);
 373 }
 374
 375 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 376                                           struct snd_info_buffer *buffer)
 377 {
 378         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 379                                buffer);
 380 }
 381
 382 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 383                                              struct snd_info_buffer *buffer)
 384 {
 385         snd_pcm_proc_info_read(entry->private_data, buffer);
 386 }
 387
 388 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 389                                                   struct snd_info_buffer *buffer)
 390 {
 391         struct snd_pcm_substream *substream = entry->private_data;
 392         struct snd_pcm_runtime *runtime;
 393
 394         mutex_lock(&substream->pcm->open_mutex);
 395         runtime = substream->runtime;
 396         if (!runtime) {
 397                 snd_iprintf(buffer, "closed\n");
 398                 goto unlock;
 399         }
 400         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 401                 snd_iprintf(buffer, "no setup\n");
 402                 goto unlock;
 403         }
 404         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 405         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 406         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 407         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 408         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 409         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 410         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 411 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 412         if (substream->oss.oss) {
 413                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 414                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 415                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 416                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 417                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 418                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 419         }
 420 #endif
 421  unlock:
 422         mutex_unlock(&substream->pcm->open_mutex);
 423 }
 424
 425 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 426                                                   struct snd_info_buffer *buffer)
 427 {
 428         struct snd_pcm_substream *substream = entry->private_data;
 429         struct snd_pcm_runtime *runtime;
 430
 431         mutex_lock(&substream->pcm->open_mutex);
 432         runtime = substream->runtime;
 433         if (!runtime) {
 434                 snd_iprintf(buffer, "closed\n");
 435                 goto unlock;
 436         }
 437         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 438                 snd_iprintf(buffer, "no setup\n");
 439                 goto unlock;
 440         }
 441         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 442         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 443         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 444         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 445         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 446         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 447         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 448         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 449  unlock:
 450         mutex_unlock(&substream->pcm->open_mutex);
 451 }
 452
 453 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 454                                                struct snd_info_buffer *buffer)
 455 {
 456         struct snd_pcm_substream *substream = entry->private_data;
 457         struct snd_pcm_runtime *runtime;
 458         struct snd_pcm_status status;
 459         int err;
 460
 461         mutex_lock(&substream->pcm->open_mutex);
 462         runtime = substream->runtime;
 463         if (!runtime) {
 464                 snd_iprintf(buffer, "closed\n");
 465                 goto unlock;
 466         }
 467         memset(&status, 0, sizeof(status));
 468         err = snd_pcm_status(substream, &status);
 469         if (err < 0) {
 470                 snd_iprintf(buffer, "error %d\n", err);
 471                 goto unlock;
 472         }
 473         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 474         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 475         snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
 476                 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
 477         snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
 478                 status.tstamp.tv_sec, status.tstamp.tv_nsec);
 479         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 480         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 481         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 482         snd_iprintf(buffer, "-----\n");
 483         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 484         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 485  unlock:
 486         mutex_unlock(&substream->pcm->open_mutex);
 487 }
 488
 489 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 490 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
 491                                          struct snd_info_buffer *buffer)
 492 {
 493         struct snd_pcm_substream *substream = entry->private_data;
 494         struct snd_pcm_runtime *runtime;
 495
 496         snd_pcm_stream_lock_irq(substream);
 497         runtime = substream->runtime;
 498         if (runtime && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
 499                 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 500         snd_pcm_stream_unlock_irq(substream);
 501 }
 502
 503 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 504                                     struct snd_info_buffer *buffer)
 505 {
 506         struct snd_pcm_str *pstr = entry->private_data;
 507         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 508 }
 509
 510 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 511                                      struct snd_info_buffer *buffer)
 512 {
 513         struct snd_pcm_str *pstr = entry->private_data;
 514         char line[64];
 515         if (!snd_info_get_line(buffer, line, sizeof(line)))
 516                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 517 }
 518 #endif
 519
 520 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 521 {
 522         struct snd_pcm *pcm = pstr->pcm;
 523         struct snd_info_entry *entry;
 524         char name[16];
 525
 526         sprintf(name, "pcm%i%c", pcm->device,
 527                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 528         entry = snd_info_create_card_entry(pcm->card, name,
 529                                            pcm->card->proc_root);
 530         if (!entry)
 531                 return -ENOMEM;
 532         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 533         if (snd_info_register(entry) < 0) {
 534                 snd_info_free_entry(entry);
 535                 return -ENOMEM;
 536         }
 537         pstr->proc_root = entry;
 538         entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
 539         if (entry) {
 540                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 541                 if (snd_info_register(entry) < 0) {
 542                         snd_info_free_entry(entry);
 543                         entry = NULL;
 544                 }
 545         }
 546         pstr->proc_info_entry = entry;
 547
 548 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 549         entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 550                                            pstr->proc_root);
 551         if (entry) {
 552                 entry->c.text.read = snd_pcm_xrun_debug_read;
 553                 entry->c.text.write = snd_pcm_xrun_debug_write;
 554                 entry->mode |= S_IWUSR;
 555                 entry->private_data = pstr;
 556                 if (snd_info_register(entry) < 0) {
 557                         snd_info_free_entry(entry);
 558                         entry = NULL;
 559                 }
 560         }
 561         pstr->proc_xrun_debug_entry = entry;
 562 #endif
 563         return 0;
 564 }
 565
 566 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 567 {
 568 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 569         snd_info_free_entry(pstr->proc_xrun_debug_entry);
 570         pstr->proc_xrun_debug_entry = NULL;
 571 #endif
 572         snd_info_free_entry(pstr->proc_info_entry);
 573         pstr->proc_info_entry = NULL;
 574         snd_info_free_entry(pstr->proc_root);
 575         pstr->proc_root = NULL;
 576         return 0;
 577 }
 578
 579 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 580 {
 581         struct snd_info_entry *entry;
 582         struct snd_card *card;
 583         char name[16];
 584
 585         card = substream->pcm->card;
 586
 587         sprintf(name, "sub%i", substream->number);
 588         entry = snd_info_create_card_entry(card, name,
 589                                            substream->pstr->proc_root);
 590         if (!entry)
 591                 return -ENOMEM;
 592         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 593         if (snd_info_register(entry) < 0) {
 594                 snd_info_free_entry(entry);
 595                 return -ENOMEM;
 596         }
 597         substream->proc_root = entry;
 598         entry = snd_info_create_card_entry(card, "info", substream->proc_root);
 599         if (entry) {
 600                 snd_info_set_text_ops(entry, substream,
 601                                       snd_pcm_substream_proc_info_read);
 602                 if (snd_info_register(entry) < 0) {
 603                         snd_info_free_entry(entry);
 604                         entry = NULL;
 605                 }
 606         }
 607         substream->proc_info_entry = entry;
 608         entry = snd_info_create_card_entry(card, "hw_params",
 609                                            substream->proc_root);
 610         if (entry) {
 611                 snd_info_set_text_ops(entry, substream,
 612                                       snd_pcm_substream_proc_hw_params_read);
 613                 if (snd_info_register(entry) < 0) {
 614                         snd_info_free_entry(entry);
 615                         entry = NULL;
 616                 }
 617         }
 618         substream->proc_hw_params_entry = entry;
 619         entry = snd_info_create_card_entry(card, "sw_params",
 620                                            substream->proc_root);
 621         if (entry) {
 622                 snd_info_set_text_ops(entry, substream,
 623                                       snd_pcm_substream_proc_sw_params_read);
 624                 if (snd_info_register(entry) < 0) {
 625                         snd_info_free_entry(entry);
 626                         entry = NULL;
 627                 }
 628         }
 629         substream->proc_sw_params_entry = entry;
 630         entry = snd_info_create_card_entry(card, "status",
 631                                            substream->proc_root);
 632         if (entry) {
 633                 snd_info_set_text_ops(entry, substream,
 634                                       snd_pcm_substream_proc_status_read);
 635                 if (snd_info_register(entry) < 0) {
 636                         snd_info_free_entry(entry);
 637                         entry = NULL;
 638                 }
 639         }
 640         substream->proc_status_entry = entry;
 641
 642 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 643         entry = snd_info_create_card_entry(card, "xrun_injection",
 644                                            substream->proc_root);
 645         if (entry) {
 646                 entry->private_data = substream;
 647                 entry->c.text.read = NULL;
 648                 entry->c.text.write = snd_pcm_xrun_injection_write;
 649                 entry->mode = S_IFREG | S_IWUSR;
 650                 if (snd_info_register(entry) < 0) {
 651                         snd_info_free_entry(entry);
 652                         entry = NULL;
 653                 }
 654         }
 655         substream->proc_xrun_injection_entry = entry;
 656 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
 657
 658         return 0;
 659 }
 660
 661 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 662 {
 663         snd_info_free_entry(substream->proc_info_entry);
 664         substream->proc_info_entry = NULL;
 665         snd_info_free_entry(substream->proc_hw_params_entry);
 666         substream->proc_hw_params_entry = NULL;
 667         snd_info_free_entry(substream->proc_sw_params_entry);
 668         substream->proc_sw_params_entry = NULL;
 669         snd_info_free_entry(substream->proc_status_entry);
 670         substream->proc_status_entry = NULL;
 671 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 672         snd_info_free_entry(substream->proc_xrun_injection_entry);
 673         substream->proc_xrun_injection_entry = NULL;
 674 #endif
 675         snd_info_free_entry(substream->proc_root);
 676         substream->proc_root = NULL;
 677         return 0;
 678 }
 679 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 680 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 681 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 682 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 683 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
 684 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 685
 686 static const struct attribute_group *pcm_dev_attr_groups[];
 687
 688 /**
 689  * snd_pcm_new_stream - create a new PCM stream
 690  * @pcm: the pcm instance
 691  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 692  * @substream_count: the number of substreams
 693  *
 694  * Creates a new stream for the pcm.
 695  * The corresponding stream on the pcm must have been empty before
 696  * calling this, i.e. zero must be given to the argument of
 697  * snd_pcm_new().
 698  *
 699  * Return: Zero if successful, or a negative error code on failure.
 700  */
 701 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 702 {
 703         int idx, err;
 704         struct snd_pcm_str *pstr = &pcm->streams[stream];
 705         struct snd_pcm_substream *substream, *prev;
 706
 707 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 708         mutex_init(&pstr->oss.setup_mutex);
 709 #endif
 710         pstr->stream = stream;
 711         pstr->pcm = pcm;
 712         pstr->substream_count = substream_count;
 713         if (!substream_count)
 714                 return 0;
 715
 716         snd_device_initialize(&pstr->dev, pcm->card);
 717         pstr->dev.groups = pcm_dev_attr_groups;
 718         dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
 719                      stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 720
 721         if (!pcm->internal) {
 722                 err = snd_pcm_stream_proc_init(pstr);
 723                 if (err < 0) {
 724                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 725                         return err;
 726                 }
 727         }
 728         prev = NULL;
 729         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 730                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 731                 if (!substream)
 732                         return -ENOMEM;
 733                 substream->pcm = pcm;
 734                 substream->pstr = pstr;
 735                 substream->number = idx;
 736                 substream->stream = stream;
 737                 sprintf(substream->name, "subdevice #%i", idx);
 738                 substream->buffer_bytes_max = UINT_MAX;
 739                 if (prev == NULL)
 740                         pstr->substream = substream;
 741                 else
 742                         prev->next = substream;
 743
 744                 if (!pcm->internal) {
 745                         err = snd_pcm_substream_proc_init(substream);
 746                         if (err < 0) {
 747                                 pcm_err(pcm,
 748                                         "Error in snd_pcm_stream_proc_init\n");
 749                                 if (prev == NULL)
 750                                         pstr->substream = NULL;
 751                                 else
 752                                         prev->next = NULL;
 753                                 kfree(substream);
 754                                 return err;
 755                         }
 756                 }
 757                 substream->group = &substream->self_group;
 758                 spin_lock_init(&substream->self_group.lock);
 759                 mutex_init(&substream->self_group.mutex);
 760                 INIT_LIST_HEAD(&substream->self_group.substreams);
 761                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 762                 atomic_set(&substream->mmap_count, 0);
 763                 prev = substream;
 764         }
 765         return 0;
 766 }
 767 EXPORT_SYMBOL(snd_pcm_new_stream);
 768
 769 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 770                 int playback_count, int capture_count, bool internal,
 771                 struct snd_pcm **rpcm)
 772 {
 773         struct snd_pcm *pcm;
 774         int err;
 775         static struct snd_device_ops ops = {
 776                 .dev_free = snd_pcm_dev_free,
 777                 .dev_register = snd_pcm_dev_register,
 778                 .dev_disconnect = snd_pcm_dev_disconnect,
 779         };
 780         static struct snd_device_ops internal_ops = {
 781                 .dev_free = snd_pcm_dev_free,
 782         };
 783
 784         if (snd_BUG_ON(!card))
 785                 return -ENXIO;
 786         if (rpcm)
 787                 *rpcm = NULL;
 788         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 789         if (!pcm)
 790                 return -ENOMEM;
 791         pcm->card = card;
 792         pcm->device = device;
 793         pcm->internal = internal;
 794         mutex_init(&pcm->open_mutex);
 795         init_waitqueue_head(&pcm->open_wait);
 796         INIT_LIST_HEAD(&pcm->list);
 797         if (id)
 798                 strlcpy(pcm->id, id, sizeof(pcm->id));
 799
 800         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
 801                                  playback_count);
 802         if (err < 0)
 803                 goto free_pcm;
 804
 805         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
 806         if (err < 0)
 807                 goto free_pcm;
 808
 809         err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
 810                              internal ? &internal_ops : &ops);
 811         if (err < 0)
 812                 goto free_pcm;
 813
 814         if (rpcm)
 815                 *rpcm = pcm;
 816         return 0;
 817
 818 free_pcm:
 819         snd_pcm_free(pcm);
 820         return err;
 821 }
 822
 823 /**
 824  * snd_pcm_new - create a new PCM instance
 825  * @card: the card instance
 826  * @id: the id string
 827  * @device: the device index (zero based)
 828  * @playback_count: the number of substreams for playback
 829  * @capture_count: the number of substreams for capture
 830  * @rpcm: the pointer to store the new pcm instance
 831  *
 832  * Creates a new PCM instance.
 833  *
 834  * The pcm operators have to be set afterwards to the new instance
 835  * via snd_pcm_set_ops().
 836  *
 837  * Return: Zero if successful, or a negative error code on failure.
 838  */
 839 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 840                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 841 {
 842         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 843                         false, rpcm);
 844 }
 845 EXPORT_SYMBOL(snd_pcm_new);
 846
 847 /**
 848  * snd_pcm_new_internal - create a new internal PCM instance
 849  * @card: the card instance
 850  * @id: the id string
 851  * @device: the device index (zero based - shared with normal PCMs)
 852  * @playback_count: the number of substreams for playback
 853  * @capture_count: the number of substreams for capture
 854  * @rpcm: the pointer to store the new pcm instance
 855  *
 856  * Creates a new internal PCM instance with no userspace device or procfs
 857  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 858  * will only be used internally by kernel drivers. i.e. it cannot be opened
 859  * by userspace. It provides existing ASoC components drivers with a substream
 860  * and access to any private data.
 861  *
 862  * The pcm operators have to be set afterwards to the new instance
 863  * via snd_pcm_set_ops().
 864  *
 865  * Return: Zero if successful, or a negative error code on failure.
 866  */
 867 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 868         int playback_count, int capture_count,
 869         struct snd_pcm **rpcm)
 870 {
 871         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 872                         true, rpcm);
 873 }
 874 EXPORT_SYMBOL(snd_pcm_new_internal);
 875
 876 static void free_chmap(struct snd_pcm_str *pstr)
 877 {
 878         if (pstr->chmap_kctl) {
 879                 snd_ctl_remove(pstr->pcm->card, pstr->chmap_kctl);
 880                 pstr->chmap_kctl = NULL;
 881         }
 882 }
 883
 884 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 885 {
 886         struct snd_pcm_substream *substream, *substream_next;
 887 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 888         struct snd_pcm_oss_setup *setup, *setupn;
 889 #endif
 890         substream = pstr->substream;
 891         while (substream) {
 892                 substream_next = substream->next;
 893                 snd_pcm_timer_done(substream);
 894                 snd_pcm_substream_proc_done(substream);
 895                 kfree(substream);
 896                 substream = substream_next;
 897         }
 898         snd_pcm_stream_proc_done(pstr);
 899 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 900         for (setup = pstr->oss.setup_list; setup; setup = setupn) {
 901                 setupn = setup->next;
 902                 kfree(setup->task_name);
 903                 kfree(setup);
 904         }
 905 #endif
 906         free_chmap(pstr);
 907         if (pstr->substream_count)
 908                 put_device(&pstr->dev);
 909 }
 910
 911 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 912 #define pcm_call_notify(pcm, call)                                      \
 913         do {                                                            \
 914                 struct snd_pcm_notify *_notify;                         \
 915                 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
 916                         _notify->call(pcm);                             \
 917         } while (0)
 918 #else
 919 #define pcm_call_notify(pcm, call) do {} while (0)
 920 #endif
 921
 922 static int snd_pcm_free(struct snd_pcm *pcm)
 923 {
 924         if (!pcm)
 925                 return 0;
 926         if (!pcm->internal)
 927                 pcm_call_notify(pcm, n_unregister);
 928         if (pcm->private_free)
 929                 pcm->private_free(pcm);
 930         snd_pcm_lib_preallocate_free_for_all(pcm);
 931         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
 932         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
 933         kfree(pcm);
 934         return 0;
 935 }
 936
 937 static int snd_pcm_dev_free(struct snd_device *device)
 938 {
 939         struct snd_pcm *pcm = device->device_data;
 940         return snd_pcm_free(pcm);
 941 }
 942
 943 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 944                              struct file *file,
 945                              struct snd_pcm_substream **rsubstream)
 946 {
 947         struct snd_pcm_str * pstr;
 948         struct snd_pcm_substream *substream;
 949         struct snd_pcm_runtime *runtime;
 950         struct snd_card *card;
 951         int prefer_subdevice;
 952         size_t size;
 953
 954         if (snd_BUG_ON(!pcm || !rsubstream))
 955                 return -ENXIO;
 956         if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
 957                        stream != SNDRV_PCM_STREAM_CAPTURE))
 958                 return -EINVAL;
 959         *rsubstream = NULL;
 960         pstr = &pcm->streams[stream];
 961         if (pstr->substream == NULL || pstr->substream_count == 0)
 962                 return -ENODEV;
 963
 964         card = pcm->card;
 965         prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
 966
 967         if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 968                 int opposite = !stream;
 969
 970                 for (substream = pcm->streams[opposite].substream; substream;
 971                      substream = substream->next) {
 972                         if (SUBSTREAM_BUSY(substream))
 973                                 return -EAGAIN;
 974                 }
 975         }
 976
 977         if (file->f_flags & O_APPEND) {
 978                 if (prefer_subdevice < 0) {
 979                         if (pstr->substream_count > 1)
 980                                 return -EINVAL; /* must be unique */
 981                         substream = pstr->substream;
 982                 } else {
 983                         for (substream = pstr->substream; substream;
 984                              substream = substream->next)
 985                                 if (substream->number == prefer_subdevice)
 986                                         break;
 987                 }
 988                 if (! substream)
 989                         return -ENODEV;
 990                 if (! SUBSTREAM_BUSY(substream))
 991                         return -EBADFD;
 992                 substream->ref_count++;
 993                 *rsubstream = substream;
 994                 return 0;
 995         }
 996
 997         for (substream = pstr->substream; substream; substream = substream->next) {
 998                 if (!SUBSTREAM_BUSY(substream) &&
 999                     (prefer_subdevice == -1 ||
1000                      substream->number == prefer_subdevice))
1001                         break;
1002         }
1003         if (substream == NULL)
1004                 return -EAGAIN;
1005
1006         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
1007         if (runtime == NULL)
1008                 return -ENOMEM;
1009
1010         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
1011         runtime->status = snd_malloc_pages(size, GFP_KERNEL);
1012         if (runtime->status == NULL) {
1013                 kfree(runtime);
1014                 return -ENOMEM;
1015         }
1016         memset((void*)runtime->status, 0, size);
1017
1018         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
1019         runtime->control = snd_malloc_pages(size, GFP_KERNEL);
1020         if (runtime->control == NULL) {
1021                 snd_free_pages((void*)runtime->status,
1022                                PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1023                 kfree(runtime);
1024                 return -ENOMEM;
1025         }
1026         memset((void*)runtime->control, 0, size);
1027
1028         init_waitqueue_head(&runtime->sleep);
1029         init_waitqueue_head(&runtime->tsleep);
1030
1031         runtime->status->state = SNDRV_PCM_STATE_OPEN;
1032
1033         substream->runtime = runtime;
1034         substream->private_data = pcm->private_data;
1035         substream->ref_count = 1;
1036         substream->f_flags = file->f_flags;
1037         substream->pid = get_pid(task_pid(current));
1038         pstr->substream_opened++;
1039         *rsubstream = substream;
1040         return 0;
1041 }
1042
1043 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1044 {
1045         struct snd_pcm_runtime *runtime;
1046
1047         if (PCM_RUNTIME_CHECK(substream))
1048                 return;
1049         runtime = substream->runtime;
1050         if (runtime->private_free != NULL)
1051                 runtime->private_free(runtime);
1052         snd_free_pages((void*)runtime->status,
1053                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1054         snd_free_pages((void*)runtime->control,
1055                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1056         kfree(runtime->hw_constraints.rules);
1057         kfree(runtime);
1058         substream->runtime = NULL;
1059         put_pid(substream->pid);
1060         substream->pid = NULL;
1061         substream->pstr->substream_opened--;
1062 }
1063
1064 static ssize_t show_pcm_class(struct device *dev,
1065                               struct device_attribute *attr, char *buf)
1066 {
1067         struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
1068         struct snd_pcm *pcm = pstr->pcm;
1069         const char *str;
1070         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1071                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1072                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1073                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1074                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1075         };
1076
1077         if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1078                 str = "none";
1079         else
1080                 str = strs[pcm->dev_class];
1081         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1082 }
1083
1084 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1085 static struct attribute *pcm_dev_attrs[] = {
1086         &dev_attr_pcm_class.attr,
1087         NULL
1088 };
1089
1090 static const struct attribute_group pcm_dev_attr_group = {
1091         .attrs  = pcm_dev_attrs,
1092 };
1093
1094 static const struct attribute_group *pcm_dev_attr_groups[] = {
1095         &pcm_dev_attr_group,
1096         NULL
1097 };
1098
1099 static int snd_pcm_dev_register(struct snd_device *device)
1100 {
1101         int cidx, err;
1102         struct snd_pcm_substream *substream;
1103         struct snd_pcm *pcm;
1104
1105         if (snd_BUG_ON(!device || !device->device_data))
1106                 return -ENXIO;
1107         pcm = device->device_data;
1108
1109         mutex_lock(&register_mutex);
1110         err = snd_pcm_add(pcm);
1111         if (err)
1112                 goto unlock;
1113         for (cidx = 0; cidx < 2; cidx++) {
1114                 int devtype = -1;
1115                 if (pcm->streams[cidx].substream == NULL)
1116                         continue;
1117                 switch (cidx) {
1118                 case SNDRV_PCM_STREAM_PLAYBACK:
1119                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1120                         break;
1121                 case SNDRV_PCM_STREAM_CAPTURE:
1122                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1123                         break;
1124                 }
1125                 /* register pcm */
1126                 err = snd_register_device(devtype, pcm->card, pcm->device,
1127                                           &snd_pcm_f_ops[cidx], pcm,
1128                                           &pcm->streams[cidx].dev);
1129                 if (err < 0) {
1130                         list_del_init(&pcm->list);
1131                         goto unlock;
1132                 }
1133
1134                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1135                         snd_pcm_timer_init(substream);
1136         }
1137
1138         pcm_call_notify(pcm, n_register);
1139
1140  unlock:
1141         mutex_unlock(&register_mutex);
1142         return err;
1143 }
1144
1145 static int snd_pcm_dev_disconnect(struct snd_device *device)
1146 {
1147         struct snd_pcm *pcm = device->device_data;
1148         struct snd_pcm_substream *substream;
1149         int cidx;
1150
1151         mutex_lock(&register_mutex);
1152         mutex_lock(&pcm->open_mutex);
1153         wake_up(&pcm->open_wait);
1154         list_del_init(&pcm->list);
1155         for (cidx = 0; cidx < 2; cidx++) {
1156                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1157                         snd_pcm_stream_lock_irq(substream);
1158                         if (substream->runtime) {
1159                                 if (snd_pcm_running(substream))
1160                                         snd_pcm_stop(substream,
1161                                                      SNDRV_PCM_STATE_DISCONNECTED);
1162                                 /* to be sure, set the state unconditionally */
1163                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1164                                 wake_up(&substream->runtime->sleep);
1165                                 wake_up(&substream->runtime->tsleep);
1166                         }
1167                         snd_pcm_stream_unlock_irq(substream);
1168                 }
1169         }
1170
1171         pcm_call_notify(pcm, n_disconnect);
1172         for (cidx = 0; cidx < 2; cidx++) {
1173                 snd_unregister_device(&pcm->streams[cidx].dev);
1174                 free_chmap(&pcm->streams[cidx]);
1175         }
1176         mutex_unlock(&pcm->open_mutex);
1177         mutex_unlock(&register_mutex);
1178         return 0;
1179 }
1180
1181 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1182 /**
1183  * snd_pcm_notify - Add/remove the notify list
1184  * @notify: PCM notify list
1185  * @nfree: 0 = register, 1 = unregister
1186  *
1187  * This adds the given notifier to the global list so that the callback is
1188  * called for each registered PCM devices.  This exists only for PCM OSS
1189  * emulation, so far.
1190  */
1191 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1192 {
1193         struct snd_pcm *pcm;
1194
1195         if (snd_BUG_ON(!notify ||
1196                        !notify->n_register ||
1197                        !notify->n_unregister ||
1198                        !notify->n_disconnect))
1199                 return -EINVAL;
1200         mutex_lock(&register_mutex);
1201         if (nfree) {
1202                 list_del(&notify->list);
1203                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1204                         notify->n_unregister(pcm);
1205         } else {
1206                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1207                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1208                         notify->n_register(pcm);
1209         }
1210         mutex_unlock(&register_mutex);
1211         return 0;
1212 }
1213 EXPORT_SYMBOL(snd_pcm_notify);
1214 #endif /* CONFIG_SND_PCM_OSS */
1215
1216 #ifdef CONFIG_SND_PROC_FS
1217 /*
1218  *  Info interface
1219  */
1220
1221 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1222                               struct snd_info_buffer *buffer)
1223 {
1224         struct snd_pcm *pcm;
1225
1226         mutex_lock(&register_mutex);
1227         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1228                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1229                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1230                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1231                         snd_iprintf(buffer, " : playback %i",
1232                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1233                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1234                         snd_iprintf(buffer, " : capture %i",
1235                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1236                 snd_iprintf(buffer, "\n");
1237         }
1238         mutex_unlock(&register_mutex);
1239 }
1240
1241 static struct snd_info_entry *snd_pcm_proc_entry;
1242
1243 static void snd_pcm_proc_init(void)
1244 {
1245         struct snd_info_entry *entry;
1246
1247         entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1248         if (entry) {
1249                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1250                 if (snd_info_register(entry) < 0) {
1251                         snd_info_free_entry(entry);
1252                         entry = NULL;
1253                 }
1254         }
1255         snd_pcm_proc_entry = entry;
1256 }
1257
1258 static void snd_pcm_proc_done(void)
1259 {
1260         snd_info_free_entry(snd_pcm_proc_entry);
1261 }
1262
1263 #else /* !CONFIG_SND_PROC_FS */
1264 #define snd_pcm_proc_init()
1265 #define snd_pcm_proc_done()
1266 #endif /* CONFIG_SND_PROC_FS */
1267
1268
1269 /*
1270  *  ENTRY functions
1271  */
1272
1273 static int __init alsa_pcm_init(void)
1274 {
1275         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1276         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1277         snd_pcm_proc_init();
1278         return 0;
1279 }
1280
1281 static void __exit alsa_pcm_exit(void)
1282 {
1283         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1284         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1285         snd_pcm_proc_done();
1286 }
1287
1288 module_init(alsa_pcm_init)
1289 module_exit(alsa_pcm_exit)