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 <linux/nospec.h>
  29 #include <sound/core.h>
  30 #include <sound/minors.h>
  31 #include <sound/pcm.h>
  32 #include <sound/timer.h>
  33 #include <sound/control.h>
  34 #include <sound/info.h>
  35
  36 #include "pcm_local.h"
  37
  38 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Abramo Bagnara <abramo@alsa-project.org>");
  39 MODULE_DESCRIPTION("Midlevel PCM code for ALSA.");
  40 MODULE_LICENSE("GPL");
  41
  42 static LIST_HEAD(snd_pcm_devices);
  43 static DEFINE_MUTEX(register_mutex);
  44 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
  45 static LIST_HEAD(snd_pcm_notify_list);
  46 #endif
  47
  48 static int snd_pcm_free(struct snd_pcm *pcm);
  49 static int snd_pcm_dev_free(struct snd_device *device);
  50 static int snd_pcm_dev_register(struct snd_device *device);
  51 static int snd_pcm_dev_disconnect(struct snd_device *device);
  52
  53 static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
  54 {
  55         struct snd_pcm *pcm;
  56
  57         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  58                 if (pcm->card == card && pcm->device == device)
  59                         return pcm;
  60         }
  61         return NULL;
  62 }
  63
  64 static int snd_pcm_next(struct snd_card *card, int device)
  65 {
  66         struct snd_pcm *pcm;
  67
  68         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  69                 if (pcm->card == card && pcm->device > device)
  70                         return pcm->device;
  71                 else if (pcm->card->number > card->number)
  72                         return -1;
  73         }
  74         return -1;
  75 }
  76
  77 static int snd_pcm_add(struct snd_pcm *newpcm)
  78 {
  79         struct snd_pcm *pcm;
  80
  81         if (newpcm->internal)
  82                 return 0;
  83
  84         list_for_each_entry(pcm, &snd_pcm_devices, list) {
  85                 if (pcm->card == newpcm->card && pcm->device == newpcm->device)
  86                         return -EBUSY;
  87                 if (pcm->card->number > newpcm->card->number ||
  88                                 (pcm->card == newpcm->card &&
  89                                 pcm->device > newpcm->device)) {
  90                         list_add(&newpcm->list, pcm->list.prev);
  91                         return 0;
  92                 }
  93         }
  94         list_add_tail(&newpcm->list, &snd_pcm_devices);
  95         return 0;
  96 }
  97
  98 static int snd_pcm_control_ioctl(struct snd_card *card,
  99                                  struct snd_ctl_file *control,
 100                                  unsigned int cmd, unsigned long arg)
 101 {
 102         switch (cmd) {
 103         case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE:
 104                 {
 105                         int device;
 106
 107                         if (get_user(device, (int __user *)arg))
 108                                 return -EFAULT;
 109                         mutex_lock(&register_mutex);
 110                         device = snd_pcm_next(card, device);
 111                         mutex_unlock(&register_mutex);
 112                         if (put_user(device, (int __user *)arg))
 113                                 return -EFAULT;
 114                         return 0;
 115                 }
 116         case SNDRV_CTL_IOCTL_PCM_INFO:
 117                 {
 118                         struct snd_pcm_info __user *info;
 119                         unsigned int device, subdevice;
 120                         int stream;
 121                         struct snd_pcm *pcm;
 122                         struct snd_pcm_str *pstr;
 123                         struct snd_pcm_substream *substream;
 124                         int err;
 125
 126                         info = (struct snd_pcm_info __user *)arg;
 127                         if (get_user(device, &info->device))
 128                                 return -EFAULT;
 129                         if (get_user(stream, &info->stream))
 130                                 return -EFAULT;
 131                         if (stream < 0 || stream > 1)
 132                                 return -EINVAL;
 133                         stream = array_index_nospec(stream, 2);
 134                         if (get_user(subdevice, &info->subdevice))
 135                                 return -EFAULT;
 136                         mutex_lock(&register_mutex);
 137                         pcm = snd_pcm_get(card, device);
 138                         if (pcm == NULL) {
 139                                 err = -ENXIO;
 140                                 goto _error;
 141                         }
 142                         pstr = &pcm->streams[stream];
 143                         if (pstr->substream_count == 0) {
 144                                 err = -ENOENT;
 145                                 goto _error;
 146                         }
 147                         if (subdevice >= pstr->substream_count) {
 148                                 err = -ENXIO;
 149                                 goto _error;
 150                         }
 151                         for (substream = pstr->substream; substream;
 152                              substream = substream->next)
 153                                 if (substream->number == (int)subdevice)
 154                                         break;
 155                         if (substream == NULL) {
 156                                 err = -ENXIO;
 157                                 goto _error;
 158                         }
 159                         mutex_lock(&pcm->open_mutex);
 160                         err = snd_pcm_info_user(substream, info);
 161                         mutex_unlock(&pcm->open_mutex);
 162                 _error:
 163                         mutex_unlock(&register_mutex);
 164                         return err;
 165                 }
 166         case SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE:
 167                 {
 168                         int val;
 169
 170                         if (get_user(val, (int __user *)arg))
 171                                 return -EFAULT;
 172                         control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
 173                         return 0;
 174                 }
 175         }
 176         return -ENOIOCTLCMD;
 177 }
 178
 179 #define FORMAT(v) [SNDRV_PCM_FORMAT_##v] = #v
 180
 181 static char *snd_pcm_format_names[] = {
 182         FORMAT(S8),
 183         FORMAT(U8),
 184         FORMAT(S16_LE),
 185         FORMAT(S16_BE),
 186         FORMAT(U16_LE),
 187         FORMAT(U16_BE),
 188         FORMAT(S24_LE),
 189         FORMAT(S24_BE),
 190         FORMAT(U24_LE),
 191         FORMAT(U24_BE),
 192         FORMAT(S32_LE),
 193         FORMAT(S32_BE),
 194         FORMAT(U32_LE),
 195         FORMAT(U32_BE),
 196         FORMAT(FLOAT_LE),
 197         FORMAT(FLOAT_BE),
 198         FORMAT(FLOAT64_LE),
 199         FORMAT(FLOAT64_BE),
 200         FORMAT(IEC958_SUBFRAME_LE),
 201         FORMAT(IEC958_SUBFRAME_BE),
 202         FORMAT(MU_LAW),
 203         FORMAT(A_LAW),
 204         FORMAT(IMA_ADPCM),
 205         FORMAT(MPEG),
 206         FORMAT(GSM),
 207         FORMAT(SPECIAL),
 208         FORMAT(S24_3LE),
 209         FORMAT(S24_3BE),
 210         FORMAT(U24_3LE),
 211         FORMAT(U24_3BE),
 212         FORMAT(S20_3LE),
 213         FORMAT(S20_3BE),
 214         FORMAT(U20_3LE),
 215         FORMAT(U20_3BE),
 216         FORMAT(S18_3LE),
 217         FORMAT(S18_3BE),
 218         FORMAT(U18_3LE),
 219         FORMAT(U18_3BE),
 220         FORMAT(G723_24),
 221         FORMAT(G723_24_1B),
 222         FORMAT(G723_40),
 223         FORMAT(G723_40_1B),
 224         FORMAT(DSD_U8),
 225         FORMAT(DSD_U16_LE),
 226         FORMAT(DSD_U32_LE),
 227         FORMAT(DSD_U16_BE),
 228         FORMAT(DSD_U32_BE),
 229 };
 230
 231 /**
 232  * snd_pcm_format_name - Return a name string for the given PCM format
 233  * @format: PCM format
 234  */
 235 const char *snd_pcm_format_name(snd_pcm_format_t format)
 236 {
 237         if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
 238                 return "Unknown";
 239         return snd_pcm_format_names[(__force unsigned int)format];
 240 }
 241 EXPORT_SYMBOL_GPL(snd_pcm_format_name);
 242
 243 #ifdef CONFIG_SND_VERBOSE_PROCFS
 244
 245 #define STATE(v) [SNDRV_PCM_STATE_##v] = #v
 246 #define STREAM(v) [SNDRV_PCM_STREAM_##v] = #v
 247 #define READY(v) [SNDRV_PCM_READY_##v] = #v
 248 #define XRUN(v) [SNDRV_PCM_XRUN_##v] = #v
 249 #define SILENCE(v) [SNDRV_PCM_SILENCE_##v] = #v
 250 #define TSTAMP(v) [SNDRV_PCM_TSTAMP_##v] = #v
 251 #define ACCESS(v) [SNDRV_PCM_ACCESS_##v] = #v
 252 #define START(v) [SNDRV_PCM_START_##v] = #v
 253 #define SUBFORMAT(v) [SNDRV_PCM_SUBFORMAT_##v] = #v
 254
 255 static char *snd_pcm_stream_names[] = {
 256         STREAM(PLAYBACK),
 257         STREAM(CAPTURE),
 258 };
 259
 260 static char *snd_pcm_state_names[] = {
 261         STATE(OPEN),
 262         STATE(SETUP),
 263         STATE(PREPARED),
 264         STATE(RUNNING),
 265         STATE(XRUN),
 266         STATE(DRAINING),
 267         STATE(PAUSED),
 268         STATE(SUSPENDED),
 269 };
 270
 271 static char *snd_pcm_access_names[] = {
 272         ACCESS(MMAP_INTERLEAVED),
 273         ACCESS(MMAP_NONINTERLEAVED),
 274         ACCESS(MMAP_COMPLEX),
 275         ACCESS(RW_INTERLEAVED),
 276         ACCESS(RW_NONINTERLEAVED),
 277 };
 278
 279 static char *snd_pcm_subformat_names[] = {
 280         SUBFORMAT(STD),
 281 };
 282
 283 static char *snd_pcm_tstamp_mode_names[] = {
 284         TSTAMP(NONE),
 285         TSTAMP(ENABLE),
 286 };
 287
 288 static const char *snd_pcm_stream_name(int stream)
 289 {
 290         return snd_pcm_stream_names[stream];
 291 }
 292
 293 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 294 {
 295         return snd_pcm_access_names[(__force int)access];
 296 }
 297
 298 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 299 {
 300         return snd_pcm_subformat_names[(__force int)subformat];
 301 }
 302
 303 static const char *snd_pcm_tstamp_mode_name(int mode)
 304 {
 305         return snd_pcm_tstamp_mode_names[mode];
 306 }
 307
 308 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 309 {
 310         return snd_pcm_state_names[(__force int)state];
 311 }
 312
 313 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 314 #include <linux/soundcard.h>
 315
 316 static const char *snd_pcm_oss_format_name(int format)
 317 {
 318         switch (format) {
 319         case AFMT_MU_LAW:
 320                 return "MU_LAW";
 321         case AFMT_A_LAW:
 322                 return "A_LAW";
 323         case AFMT_IMA_ADPCM:
 324                 return "IMA_ADPCM";
 325         case AFMT_U8:
 326                 return "U8";
 327         case AFMT_S16_LE:
 328                 return "S16_LE";
 329         case AFMT_S16_BE:
 330                 return "S16_BE";
 331         case AFMT_S8:
 332                 return "S8";
 333         case AFMT_U16_LE:
 334                 return "U16_LE";
 335         case AFMT_U16_BE:
 336                 return "U16_BE";
 337         case AFMT_MPEG:
 338                 return "MPEG";
 339         default:
 340                 return "unknown";
 341         }
 342 }
 343 #endif
 344
 345 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 346                                    struct snd_info_buffer *buffer)
 347 {
 348         struct snd_pcm_info *info;
 349         int err;
 350
 351         if (! substream)
 352                 return;
 353
 354         info = kmalloc(sizeof(*info), GFP_KERNEL);
 355         if (!info)
 356                 return;
 357
 358         err = snd_pcm_info(substream, info);
 359         if (err < 0) {
 360                 snd_iprintf(buffer, "error %d\n", err);
 361                 kfree(info);
 362                 return;
 363         }
 364         snd_iprintf(buffer, "card: %d\n", info->card);
 365         snd_iprintf(buffer, "device: %d\n", info->device);
 366         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 367         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 368         snd_iprintf(buffer, "id: %s\n", info->id);
 369         snd_iprintf(buffer, "name: %s\n", info->name);
 370         snd_iprintf(buffer, "subname: %s\n", info->subname);
 371         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 372         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 373         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 374         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 375         kfree(info);
 376 }
 377
 378 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 379                                           struct snd_info_buffer *buffer)
 380 {
 381         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 382                                buffer);
 383 }
 384
 385 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 386                                              struct snd_info_buffer *buffer)
 387 {
 388         snd_pcm_proc_info_read(entry->private_data, buffer);
 389 }
 390
 391 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 392                                                   struct snd_info_buffer *buffer)
 393 {
 394         struct snd_pcm_substream *substream = entry->private_data;
 395         struct snd_pcm_runtime *runtime;
 396
 397         mutex_lock(&substream->pcm->open_mutex);
 398         runtime = substream->runtime;
 399         if (!runtime) {
 400                 snd_iprintf(buffer, "closed\n");
 401                 goto unlock;
 402         }
 403         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 404                 snd_iprintf(buffer, "no setup\n");
 405                 goto unlock;
 406         }
 407         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 408         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 409         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 410         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 411         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 412         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 413         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 414 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 415         if (substream->oss.oss) {
 416                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 417                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 418                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 419                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 420                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 421                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 422         }
 423 #endif
 424  unlock:
 425         mutex_unlock(&substream->pcm->open_mutex);
 426 }
 427
 428 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 429                                                   struct snd_info_buffer *buffer)
 430 {
 431         struct snd_pcm_substream *substream = entry->private_data;
 432         struct snd_pcm_runtime *runtime;
 433
 434         mutex_lock(&substream->pcm->open_mutex);
 435         runtime = substream->runtime;
 436         if (!runtime) {
 437                 snd_iprintf(buffer, "closed\n");
 438                 goto unlock;
 439         }
 440         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 441                 snd_iprintf(buffer, "no setup\n");
 442                 goto unlock;
 443         }
 444         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 445         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 446         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 447         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 448         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 449         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 450         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 451         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 452  unlock:
 453         mutex_unlock(&substream->pcm->open_mutex);
 454 }
 455
 456 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 457                                                struct snd_info_buffer *buffer)
 458 {
 459         struct snd_pcm_substream *substream = entry->private_data;
 460         struct snd_pcm_runtime *runtime;
 461         struct snd_pcm_status status;
 462         int err;
 463
 464         mutex_lock(&substream->pcm->open_mutex);
 465         runtime = substream->runtime;
 466         if (!runtime) {
 467                 snd_iprintf(buffer, "closed\n");
 468                 goto unlock;
 469         }
 470         memset(&status, 0, sizeof(status));
 471         err = snd_pcm_status(substream, &status);
 472         if (err < 0) {
 473                 snd_iprintf(buffer, "error %d\n", err);
 474                 goto unlock;
 475         }
 476         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 477         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 478         snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
 479                 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
 480         snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
 481                 status.tstamp.tv_sec, status.tstamp.tv_nsec);
 482         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 483         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 484         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 485         snd_iprintf(buffer, "-----\n");
 486         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 487         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 488  unlock:
 489         mutex_unlock(&substream->pcm->open_mutex);
 490 }
 491
 492 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 493 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
 494                                          struct snd_info_buffer *buffer)
 495 {
 496         struct snd_pcm_substream *substream = entry->private_data;
 497         struct snd_pcm_runtime *runtime;
 498
 499         snd_pcm_stream_lock_irq(substream);
 500         runtime = substream->runtime;
 501         if (runtime && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
 502                 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 503         snd_pcm_stream_unlock_irq(substream);
 504 }
 505
 506 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 507                                     struct snd_info_buffer *buffer)
 508 {
 509         struct snd_pcm_str *pstr = entry->private_data;
 510         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 511 }
 512
 513 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 514                                      struct snd_info_buffer *buffer)
 515 {
 516         struct snd_pcm_str *pstr = entry->private_data;
 517         char line[64];
 518         if (!snd_info_get_line(buffer, line, sizeof(line)))
 519                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 520 }
 521 #endif
 522
 523 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 524 {
 525         struct snd_pcm *pcm = pstr->pcm;
 526         struct snd_info_entry *entry;
 527         char name[16];
 528
 529         sprintf(name, "pcm%i%c", pcm->device,
 530                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 531         entry = snd_info_create_card_entry(pcm->card, name,
 532                                            pcm->card->proc_root);
 533         if (!entry)
 534                 return -ENOMEM;
 535         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 536         if (snd_info_register(entry) < 0) {
 537                 snd_info_free_entry(entry);
 538                 return -ENOMEM;
 539         }
 540         pstr->proc_root = entry;
 541         entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
 542         if (entry) {
 543                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 544                 if (snd_info_register(entry) < 0) {
 545                         snd_info_free_entry(entry);
 546                         entry = NULL;
 547                 }
 548         }
 549         pstr->proc_info_entry = entry;
 550
 551 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 552         entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 553                                            pstr->proc_root);
 554         if (entry) {
 555                 entry->c.text.read = snd_pcm_xrun_debug_read;
 556                 entry->c.text.write = snd_pcm_xrun_debug_write;
 557                 entry->mode |= S_IWUSR;
 558                 entry->private_data = pstr;
 559                 if (snd_info_register(entry) < 0) {
 560                         snd_info_free_entry(entry);
 561                         entry = NULL;
 562                 }
 563         }
 564         pstr->proc_xrun_debug_entry = entry;
 565 #endif
 566         return 0;
 567 }
 568
 569 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 570 {
 571 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 572         snd_info_free_entry(pstr->proc_xrun_debug_entry);
 573         pstr->proc_xrun_debug_entry = NULL;
 574 #endif
 575         snd_info_free_entry(pstr->proc_info_entry);
 576         pstr->proc_info_entry = NULL;
 577         snd_info_free_entry(pstr->proc_root);
 578         pstr->proc_root = NULL;
 579         return 0;
 580 }
 581
 582 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 583 {
 584         struct snd_info_entry *entry;
 585         struct snd_card *card;
 586         char name[16];
 587
 588         card = substream->pcm->card;
 589
 590         sprintf(name, "sub%i", substream->number);
 591         entry = snd_info_create_card_entry(card, name,
 592                                            substream->pstr->proc_root);
 593         if (!entry)
 594                 return -ENOMEM;
 595         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 596         if (snd_info_register(entry) < 0) {
 597                 snd_info_free_entry(entry);
 598                 return -ENOMEM;
 599         }
 600         substream->proc_root = entry;
 601         entry = snd_info_create_card_entry(card, "info", substream->proc_root);
 602         if (entry) {
 603                 snd_info_set_text_ops(entry, substream,
 604                                       snd_pcm_substream_proc_info_read);
 605                 if (snd_info_register(entry) < 0) {
 606                         snd_info_free_entry(entry);
 607                         entry = NULL;
 608                 }
 609         }
 610         substream->proc_info_entry = entry;
 611         entry = snd_info_create_card_entry(card, "hw_params",
 612                                            substream->proc_root);
 613         if (entry) {
 614                 snd_info_set_text_ops(entry, substream,
 615                                       snd_pcm_substream_proc_hw_params_read);
 616                 if (snd_info_register(entry) < 0) {
 617                         snd_info_free_entry(entry);
 618                         entry = NULL;
 619                 }
 620         }
 621         substream->proc_hw_params_entry = entry;
 622         entry = snd_info_create_card_entry(card, "sw_params",
 623                                            substream->proc_root);
 624         if (entry) {
 625                 snd_info_set_text_ops(entry, substream,
 626                                       snd_pcm_substream_proc_sw_params_read);
 627                 if (snd_info_register(entry) < 0) {
 628                         snd_info_free_entry(entry);
 629                         entry = NULL;
 630                 }
 631         }
 632         substream->proc_sw_params_entry = entry;
 633         entry = snd_info_create_card_entry(card, "status",
 634                                            substream->proc_root);
 635         if (entry) {
 636                 snd_info_set_text_ops(entry, substream,
 637                                       snd_pcm_substream_proc_status_read);
 638                 if (snd_info_register(entry) < 0) {
 639                         snd_info_free_entry(entry);
 640                         entry = NULL;
 641                 }
 642         }
 643         substream->proc_status_entry = entry;
 644
 645 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 646         entry = snd_info_create_card_entry(card, "xrun_injection",
 647                                            substream->proc_root);
 648         if (entry) {
 649                 entry->private_data = substream;
 650                 entry->c.text.read = NULL;
 651                 entry->c.text.write = snd_pcm_xrun_injection_write;
 652                 entry->mode = S_IFREG | S_IWUSR;
 653                 if (snd_info_register(entry) < 0) {
 654                         snd_info_free_entry(entry);
 655                         entry = NULL;
 656                 }
 657         }
 658         substream->proc_xrun_injection_entry = entry;
 659 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
 660
 661         return 0;
 662 }
 663
 664 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 665 {
 666         snd_info_free_entry(substream->proc_info_entry);
 667         substream->proc_info_entry = NULL;
 668         snd_info_free_entry(substream->proc_hw_params_entry);
 669         substream->proc_hw_params_entry = NULL;
 670         snd_info_free_entry(substream->proc_sw_params_entry);
 671         substream->proc_sw_params_entry = NULL;
 672         snd_info_free_entry(substream->proc_status_entry);
 673         substream->proc_status_entry = NULL;
 674 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 675         snd_info_free_entry(substream->proc_xrun_injection_entry);
 676         substream->proc_xrun_injection_entry = NULL;
 677 #endif
 678         snd_info_free_entry(substream->proc_root);
 679         substream->proc_root = NULL;
 680         return 0;
 681 }
 682 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 683 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 684 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 685 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 686 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
 687 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 688
 689 static const struct attribute_group *pcm_dev_attr_groups[];
 690
 691 /**
 692  * snd_pcm_new_stream - create a new PCM stream
 693  * @pcm: the pcm instance
 694  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 695  * @substream_count: the number of substreams
 696  *
 697  * Creates a new stream for the pcm.
 698  * The corresponding stream on the pcm must have been empty before
 699  * calling this, i.e. zero must be given to the argument of
 700  * snd_pcm_new().
 701  *
 702  * Return: Zero if successful, or a negative error code on failure.
 703  */
 704 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 705 {
 706         int idx, err;
 707         struct snd_pcm_str *pstr = &pcm->streams[stream];
 708         struct snd_pcm_substream *substream, *prev;
 709
 710 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 711         mutex_init(&pstr->oss.setup_mutex);
 712 #endif
 713         pstr->stream = stream;
 714         pstr->pcm = pcm;
 715         pstr->substream_count = substream_count;
 716         if (!substream_count)
 717                 return 0;
 718
 719         snd_device_initialize(&pstr->dev, pcm->card);
 720         pstr->dev.groups = pcm_dev_attr_groups;
 721         dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
 722                      stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 723
 724         if (!pcm->internal) {
 725                 err = snd_pcm_stream_proc_init(pstr);
 726                 if (err < 0) {
 727                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 728                         return err;
 729                 }
 730         }
 731         prev = NULL;
 732         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 733                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 734                 if (!substream)
 735                         return -ENOMEM;
 736                 substream->pcm = pcm;
 737                 substream->pstr = pstr;
 738                 substream->number = idx;
 739                 substream->stream = stream;
 740                 sprintf(substream->name, "subdevice #%i", idx);
 741                 substream->buffer_bytes_max = UINT_MAX;
 742                 if (prev == NULL)
 743                         pstr->substream = substream;
 744                 else
 745                         prev->next = substream;
 746
 747                 if (!pcm->internal) {
 748                         err = snd_pcm_substream_proc_init(substream);
 749                         if (err < 0) {
 750                                 pcm_err(pcm,
 751                                         "Error in snd_pcm_stream_proc_init\n");
 752                                 if (prev == NULL)
 753                                         pstr->substream = NULL;
 754                                 else
 755                                         prev->next = NULL;
 756                                 kfree(substream);
 757                                 return err;
 758                         }
 759                 }
 760                 substream->group = &substream->self_group;
 761                 spin_lock_init(&substream->self_group.lock);
 762                 mutex_init(&substream->self_group.mutex);
 763                 INIT_LIST_HEAD(&substream->self_group.substreams);
 764                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 765                 atomic_set(&substream->mmap_count, 0);
 766                 prev = substream;
 767         }
 768         return 0;
 769 }
 770 EXPORT_SYMBOL(snd_pcm_new_stream);
 771
 772 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 773                 int playback_count, int capture_count, bool internal,
 774                 struct snd_pcm **rpcm)
 775 {
 776         struct snd_pcm *pcm;
 777         int err;
 778         static struct snd_device_ops ops = {
 779                 .dev_free = snd_pcm_dev_free,
 780                 .dev_register = snd_pcm_dev_register,
 781                 .dev_disconnect = snd_pcm_dev_disconnect,
 782         };
 783         static struct snd_device_ops internal_ops = {
 784                 .dev_free = snd_pcm_dev_free,
 785         };
 786
 787         if (snd_BUG_ON(!card))
 788                 return -ENXIO;
 789         if (rpcm)
 790                 *rpcm = NULL;
 791         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 792         if (!pcm)
 793                 return -ENOMEM;
 794         pcm->card = card;
 795         pcm->device = device;
 796         pcm->internal = internal;
 797         mutex_init(&pcm->open_mutex);
 798         init_waitqueue_head(&pcm->open_wait);
 799         INIT_LIST_HEAD(&pcm->list);
 800         if (id)
 801                 strlcpy(pcm->id, id, sizeof(pcm->id));
 802
 803         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
 804                                  playback_count);
 805         if (err < 0)
 806                 goto free_pcm;
 807
 808         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
 809         if (err < 0)
 810                 goto free_pcm;
 811
 812         err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
 813                              internal ? &internal_ops : &ops);
 814         if (err < 0)
 815                 goto free_pcm;
 816
 817         if (rpcm)
 818                 *rpcm = pcm;
 819         return 0;
 820
 821 free_pcm:
 822         snd_pcm_free(pcm);
 823         return err;
 824 }
 825
 826 /**
 827  * snd_pcm_new - create a new PCM instance
 828  * @card: the card instance
 829  * @id: the id string
 830  * @device: the device index (zero based)
 831  * @playback_count: the number of substreams for playback
 832  * @capture_count: the number of substreams for capture
 833  * @rpcm: the pointer to store the new pcm instance
 834  *
 835  * Creates a new PCM instance.
 836  *
 837  * The pcm operators have to be set afterwards to the new instance
 838  * via snd_pcm_set_ops().
 839  *
 840  * Return: Zero if successful, or a negative error code on failure.
 841  */
 842 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 843                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 844 {
 845         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 846                         false, rpcm);
 847 }
 848 EXPORT_SYMBOL(snd_pcm_new);
 849
 850 /**
 851  * snd_pcm_new_internal - create a new internal PCM instance
 852  * @card: the card instance
 853  * @id: the id string
 854  * @device: the device index (zero based - shared with normal PCMs)
 855  * @playback_count: the number of substreams for playback
 856  * @capture_count: the number of substreams for capture
 857  * @rpcm: the pointer to store the new pcm instance
 858  *
 859  * Creates a new internal PCM instance with no userspace device or procfs
 860  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 861  * will only be used internally by kernel drivers. i.e. it cannot be opened
 862  * by userspace. It provides existing ASoC components drivers with a substream
 863  * and access to any private data.
 864  *
 865  * The pcm operators have to be set afterwards to the new instance
 866  * via snd_pcm_set_ops().
 867  *
 868  * Return: Zero if successful, or a negative error code on failure.
 869  */
 870 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 871         int playback_count, int capture_count,
 872         struct snd_pcm **rpcm)
 873 {
 874         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 875                         true, rpcm);
 876 }
 877 EXPORT_SYMBOL(snd_pcm_new_internal);
 878
 879 static void free_chmap(struct snd_pcm_str *pstr)
 880 {
 881         if (pstr->chmap_kctl) {
 882                 snd_ctl_remove(pstr->pcm->card, pstr->chmap_kctl);
 883                 pstr->chmap_kctl = NULL;
 884         }
 885 }
 886
 887 static void snd_pcm_free_stream(struct snd_pcm_str * pstr)
 888 {
 889         struct snd_pcm_substream *substream, *substream_next;
 890 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 891         struct snd_pcm_oss_setup *setup, *setupn;
 892 #endif
 893         substream = pstr->substream;
 894         while (substream) {
 895                 substream_next = substream->next;
 896                 snd_pcm_timer_done(substream);
 897                 snd_pcm_substream_proc_done(substream);
 898                 kfree(substream);
 899                 substream = substream_next;
 900         }
 901         snd_pcm_stream_proc_done(pstr);
 902 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 903         for (setup = pstr->oss.setup_list; setup; setup = setupn) {
 904                 setupn = setup->next;
 905                 kfree(setup->task_name);
 906                 kfree(setup);
 907         }
 908 #endif
 909         free_chmap(pstr);
 910         if (pstr->substream_count)
 911                 put_device(&pstr->dev);
 912 }
 913
 914 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 915 #define pcm_call_notify(pcm, call)                                      \
 916         do {                                                            \
 917                 struct snd_pcm_notify *_notify;                         \
 918                 list_for_each_entry(_notify, &snd_pcm_notify_list, list) \
 919                         _notify->call(pcm);                             \
 920         } while (0)
 921 #else
 922 #define pcm_call_notify(pcm, call) do {} while (0)
 923 #endif
 924
 925 static int snd_pcm_free(struct snd_pcm *pcm)
 926 {
 927         if (!pcm)
 928                 return 0;
 929         if (!pcm->internal)
 930                 pcm_call_notify(pcm, n_unregister);
 931         if (pcm->private_free)
 932                 pcm->private_free(pcm);
 933         snd_pcm_lib_preallocate_free_for_all(pcm);
 934         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK]);
 935         snd_pcm_free_stream(&pcm->streams[SNDRV_PCM_STREAM_CAPTURE]);
 936         kfree(pcm);
 937         return 0;
 938 }
 939
 940 static int snd_pcm_dev_free(struct snd_device *device)
 941 {
 942         struct snd_pcm *pcm = device->device_data;
 943         return snd_pcm_free(pcm);
 944 }
 945
 946 int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
 947                              struct file *file,
 948                              struct snd_pcm_substream **rsubstream)
 949 {
 950         struct snd_pcm_str * pstr;
 951         struct snd_pcm_substream *substream;
 952         struct snd_pcm_runtime *runtime;
 953         struct snd_card *card;
 954         int prefer_subdevice;
 955         size_t size;
 956
 957         if (snd_BUG_ON(!pcm || !rsubstream))
 958                 return -ENXIO;
 959         if (snd_BUG_ON(stream != SNDRV_PCM_STREAM_PLAYBACK &&
 960                        stream != SNDRV_PCM_STREAM_CAPTURE))
 961                 return -EINVAL;
 962         *rsubstream = NULL;
 963         pstr = &pcm->streams[stream];
 964         if (pstr->substream == NULL || pstr->substream_count == 0)
 965                 return -ENODEV;
 966
 967         card = pcm->card;
 968         prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
 969
 970         if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
 971                 int opposite = !stream;
 972
 973                 for (substream = pcm->streams[opposite].substream; substream;
 974                      substream = substream->next) {
 975                         if (SUBSTREAM_BUSY(substream))
 976                                 return -EAGAIN;
 977                 }
 978         }
 979
 980         if (file->f_flags & O_APPEND) {
 981                 if (prefer_subdevice < 0) {
 982                         if (pstr->substream_count > 1)
 983                                 return -EINVAL; /* must be unique */
 984                         substream = pstr->substream;
 985                 } else {
 986                         for (substream = pstr->substream; substream;
 987                              substream = substream->next)
 988                                 if (substream->number == prefer_subdevice)
 989                                         break;
 990                 }
 991                 if (! substream)
 992                         return -ENODEV;
 993                 if (! SUBSTREAM_BUSY(substream))
 994                         return -EBADFD;
 995                 substream->ref_count++;
 996                 *rsubstream = substream;
 997                 return 0;
 998         }
 999
1000         for (substream = pstr->substream; substream; substream = substream->next) {
1001                 if (!SUBSTREAM_BUSY(substream) &&
1002                     (prefer_subdevice == -1 ||
1003                      substream->number == prefer_subdevice))
1004                         break;
1005         }
1006         if (substream == NULL)
1007                 return -EAGAIN;
1008
1009         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
1010         if (runtime == NULL)
1011                 return -ENOMEM;
1012
1013         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status));
1014         runtime->status = snd_malloc_pages(size, GFP_KERNEL);
1015         if (runtime->status == NULL) {
1016                 kfree(runtime);
1017                 return -ENOMEM;
1018         }
1019         memset((void*)runtime->status, 0, size);
1020
1021         size = PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control));
1022         runtime->control = snd_malloc_pages(size, GFP_KERNEL);
1023         if (runtime->control == NULL) {
1024                 snd_free_pages((void*)runtime->status,
1025                                PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1026                 kfree(runtime);
1027                 return -ENOMEM;
1028         }
1029         memset((void*)runtime->control, 0, size);
1030
1031         init_waitqueue_head(&runtime->sleep);
1032         init_waitqueue_head(&runtime->tsleep);
1033
1034         runtime->status->state = SNDRV_PCM_STATE_OPEN;
1035
1036         substream->runtime = runtime;
1037         substream->private_data = pcm->private_data;
1038         substream->ref_count = 1;
1039         substream->f_flags = file->f_flags;
1040         substream->pid = get_pid(task_pid(current));
1041         pstr->substream_opened++;
1042         *rsubstream = substream;
1043         return 0;
1044 }
1045
1046 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1047 {
1048         struct snd_pcm_runtime *runtime;
1049
1050         if (PCM_RUNTIME_CHECK(substream))
1051                 return;
1052         runtime = substream->runtime;
1053         if (runtime->private_free != NULL)
1054                 runtime->private_free(runtime);
1055         snd_free_pages((void*)runtime->status,
1056                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1057         snd_free_pages((void*)runtime->control,
1058                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1059         kfree(runtime->hw_constraints.rules);
1060         /* Avoid concurrent access to runtime via PCM timer interface */
1061         if (substream->timer)
1062                 spin_lock_irq(&substream->timer->lock);
1063         substream->runtime = NULL;
1064         if (substream->timer)
1065                 spin_unlock_irq(&substream->timer->lock);
1066         kfree(runtime);
1067         put_pid(substream->pid);
1068         substream->pid = NULL;
1069         substream->pstr->substream_opened--;
1070 }
1071
1072 static ssize_t show_pcm_class(struct device *dev,
1073                               struct device_attribute *attr, char *buf)
1074 {
1075         struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
1076         struct snd_pcm *pcm = pstr->pcm;
1077         const char *str;
1078         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1079                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1080                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1081                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1082                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1083         };
1084
1085         if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1086                 str = "none";
1087         else
1088                 str = strs[pcm->dev_class];
1089         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1090 }
1091
1092 static DEVICE_ATTR(pcm_class, S_IRUGO, show_pcm_class, NULL);
1093 static struct attribute *pcm_dev_attrs[] = {
1094         &dev_attr_pcm_class.attr,
1095         NULL
1096 };
1097
1098 static const struct attribute_group pcm_dev_attr_group = {
1099         .attrs  = pcm_dev_attrs,
1100 };
1101
1102 static const struct attribute_group *pcm_dev_attr_groups[] = {
1103         &pcm_dev_attr_group,
1104         NULL
1105 };
1106
1107 static int snd_pcm_dev_register(struct snd_device *device)
1108 {
1109         int cidx, err;
1110         struct snd_pcm_substream *substream;
1111         struct snd_pcm *pcm;
1112
1113         if (snd_BUG_ON(!device || !device->device_data))
1114                 return -ENXIO;
1115         pcm = device->device_data;
1116
1117         mutex_lock(&register_mutex);
1118         err = snd_pcm_add(pcm);
1119         if (err)
1120                 goto unlock;
1121         for (cidx = 0; cidx < 2; cidx++) {
1122                 int devtype = -1;
1123                 if (pcm->streams[cidx].substream == NULL)
1124                         continue;
1125                 switch (cidx) {
1126                 case SNDRV_PCM_STREAM_PLAYBACK:
1127                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1128                         break;
1129                 case SNDRV_PCM_STREAM_CAPTURE:
1130                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1131                         break;
1132                 }
1133                 /* register pcm */
1134                 err = snd_register_device(devtype, pcm->card, pcm->device,
1135                                           &snd_pcm_f_ops[cidx], pcm,
1136                                           &pcm->streams[cidx].dev);
1137                 if (err < 0) {
1138                         list_del_init(&pcm->list);
1139                         goto unlock;
1140                 }
1141
1142                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1143                         snd_pcm_timer_init(substream);
1144         }
1145
1146         pcm_call_notify(pcm, n_register);
1147
1148  unlock:
1149         mutex_unlock(&register_mutex);
1150         return err;
1151 }
1152
1153 static int snd_pcm_dev_disconnect(struct snd_device *device)
1154 {
1155         struct snd_pcm *pcm = device->device_data;
1156         struct snd_pcm_substream *substream;
1157         int cidx;
1158
1159         mutex_lock(&register_mutex);
1160         mutex_lock(&pcm->open_mutex);
1161         wake_up(&pcm->open_wait);
1162         list_del_init(&pcm->list);
1163         for (cidx = 0; cidx < 2; cidx++) {
1164                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1165                         snd_pcm_stream_lock_irq(substream);
1166                         if (substream->runtime) {
1167                                 if (snd_pcm_running(substream))
1168                                         snd_pcm_stop(substream,
1169                                                      SNDRV_PCM_STATE_DISCONNECTED);
1170                                 /* to be sure, set the state unconditionally */
1171                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1172                                 wake_up(&substream->runtime->sleep);
1173                                 wake_up(&substream->runtime->tsleep);
1174                         }
1175                         snd_pcm_stream_unlock_irq(substream);
1176                 }
1177         }
1178
1179         pcm_call_notify(pcm, n_disconnect);
1180         for (cidx = 0; cidx < 2; cidx++) {
1181                 snd_unregister_device(&pcm->streams[cidx].dev);
1182                 free_chmap(&pcm->streams[cidx]);
1183         }
1184         mutex_unlock(&pcm->open_mutex);
1185         mutex_unlock(&register_mutex);
1186         return 0;
1187 }
1188
1189 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1190 /**
1191  * snd_pcm_notify - Add/remove the notify list
1192  * @notify: PCM notify list
1193  * @nfree: 0 = register, 1 = unregister
1194  *
1195  * This adds the given notifier to the global list so that the callback is
1196  * called for each registered PCM devices.  This exists only for PCM OSS
1197  * emulation, so far.
1198  */
1199 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1200 {
1201         struct snd_pcm *pcm;
1202
1203         if (snd_BUG_ON(!notify ||
1204                        !notify->n_register ||
1205                        !notify->n_unregister ||
1206                        !notify->n_disconnect))
1207                 return -EINVAL;
1208         mutex_lock(&register_mutex);
1209         if (nfree) {
1210                 list_del(&notify->list);
1211                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1212                         notify->n_unregister(pcm);
1213         } else {
1214                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1215                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1216                         notify->n_register(pcm);
1217         }
1218         mutex_unlock(&register_mutex);
1219         return 0;
1220 }
1221 EXPORT_SYMBOL(snd_pcm_notify);
1222 #endif /* CONFIG_SND_PCM_OSS */
1223
1224 #ifdef CONFIG_SND_PROC_FS
1225 /*
1226  *  Info interface
1227  */
1228
1229 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1230                               struct snd_info_buffer *buffer)
1231 {
1232         struct snd_pcm *pcm;
1233
1234         mutex_lock(&register_mutex);
1235         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1236                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1237                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1238                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1239                         snd_iprintf(buffer, " : playback %i",
1240                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1241                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1242                         snd_iprintf(buffer, " : capture %i",
1243                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1244                 snd_iprintf(buffer, "\n");
1245         }
1246         mutex_unlock(&register_mutex);
1247 }
1248
1249 static struct snd_info_entry *snd_pcm_proc_entry;
1250
1251 static void snd_pcm_proc_init(void)
1252 {
1253         struct snd_info_entry *entry;
1254
1255         entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1256         if (entry) {
1257                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1258                 if (snd_info_register(entry) < 0) {
1259                         snd_info_free_entry(entry);
1260                         entry = NULL;
1261                 }
1262         }
1263         snd_pcm_proc_entry = entry;
1264 }
1265
1266 static void snd_pcm_proc_done(void)
1267 {
1268         snd_info_free_entry(snd_pcm_proc_entry);
1269 }
1270
1271 #else /* !CONFIG_SND_PROC_FS */
1272 #define snd_pcm_proc_init()
1273 #define snd_pcm_proc_done()
1274 #endif /* CONFIG_SND_PROC_FS */
1275
1276
1277 /*
1278  *  ENTRY functions
1279  */
1280
1281 static int __init alsa_pcm_init(void)
1282 {
1283         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1284         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1285         snd_pcm_proc_init();
1286         return 0;
1287 }
1288
1289 static void __exit alsa_pcm_exit(void)
1290 {
1291         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1292         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1293         snd_pcm_proc_done();
1294 }
1295
1296 module_init(alsa_pcm_init)
1297 module_exit(alsa_pcm_exit)