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         STATE(DISCONNECTED),
 270 };
 271
 272 static char *snd_pcm_access_names[] = {
 273         ACCESS(MMAP_INTERLEAVED),
 274         ACCESS(MMAP_NONINTERLEAVED),
 275         ACCESS(MMAP_COMPLEX),
 276         ACCESS(RW_INTERLEAVED),
 277         ACCESS(RW_NONINTERLEAVED),
 278 };
 279
 280 static char *snd_pcm_subformat_names[] = {
 281         SUBFORMAT(STD),
 282 };
 283
 284 static char *snd_pcm_tstamp_mode_names[] = {
 285         TSTAMP(NONE),
 286         TSTAMP(ENABLE),
 287 };
 288
 289 static const char *snd_pcm_stream_name(int stream)
 290 {
 291         return snd_pcm_stream_names[stream];
 292 }
 293
 294 static const char *snd_pcm_access_name(snd_pcm_access_t access)
 295 {
 296         return snd_pcm_access_names[(__force int)access];
 297 }
 298
 299 static const char *snd_pcm_subformat_name(snd_pcm_subformat_t subformat)
 300 {
 301         return snd_pcm_subformat_names[(__force int)subformat];
 302 }
 303
 304 static const char *snd_pcm_tstamp_mode_name(int mode)
 305 {
 306         return snd_pcm_tstamp_mode_names[mode];
 307 }
 308
 309 static const char *snd_pcm_state_name(snd_pcm_state_t state)
 310 {
 311         return snd_pcm_state_names[(__force int)state];
 312 }
 313
 314 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 315 #include <linux/soundcard.h>
 316
 317 static const char *snd_pcm_oss_format_name(int format)
 318 {
 319         switch (format) {
 320         case AFMT_MU_LAW:
 321                 return "MU_LAW";
 322         case AFMT_A_LAW:
 323                 return "A_LAW";
 324         case AFMT_IMA_ADPCM:
 325                 return "IMA_ADPCM";
 326         case AFMT_U8:
 327                 return "U8";
 328         case AFMT_S16_LE:
 329                 return "S16_LE";
 330         case AFMT_S16_BE:
 331                 return "S16_BE";
 332         case AFMT_S8:
 333                 return "S8";
 334         case AFMT_U16_LE:
 335                 return "U16_LE";
 336         case AFMT_U16_BE:
 337                 return "U16_BE";
 338         case AFMT_MPEG:
 339                 return "MPEG";
 340         default:
 341                 return "unknown";
 342         }
 343 }
 344 #endif
 345
 346 static void snd_pcm_proc_info_read(struct snd_pcm_substream *substream,
 347                                    struct snd_info_buffer *buffer)
 348 {
 349         struct snd_pcm_info *info;
 350         int err;
 351
 352         if (! substream)
 353                 return;
 354
 355         info = kmalloc(sizeof(*info), GFP_KERNEL);
 356         if (!info)
 357                 return;
 358
 359         err = snd_pcm_info(substream, info);
 360         if (err < 0) {
 361                 snd_iprintf(buffer, "error %d\n", err);
 362                 kfree(info);
 363                 return;
 364         }
 365         snd_iprintf(buffer, "card: %d\n", info->card);
 366         snd_iprintf(buffer, "device: %d\n", info->device);
 367         snd_iprintf(buffer, "subdevice: %d\n", info->subdevice);
 368         snd_iprintf(buffer, "stream: %s\n", snd_pcm_stream_name(info->stream));
 369         snd_iprintf(buffer, "id: %s\n", info->id);
 370         snd_iprintf(buffer, "name: %s\n", info->name);
 371         snd_iprintf(buffer, "subname: %s\n", info->subname);
 372         snd_iprintf(buffer, "class: %d\n", info->dev_class);
 373         snd_iprintf(buffer, "subclass: %d\n", info->dev_subclass);
 374         snd_iprintf(buffer, "subdevices_count: %d\n", info->subdevices_count);
 375         snd_iprintf(buffer, "subdevices_avail: %d\n", info->subdevices_avail);
 376         kfree(info);
 377 }
 378
 379 static void snd_pcm_stream_proc_info_read(struct snd_info_entry *entry,
 380                                           struct snd_info_buffer *buffer)
 381 {
 382         snd_pcm_proc_info_read(((struct snd_pcm_str *)entry->private_data)->substream,
 383                                buffer);
 384 }
 385
 386 static void snd_pcm_substream_proc_info_read(struct snd_info_entry *entry,
 387                                              struct snd_info_buffer *buffer)
 388 {
 389         snd_pcm_proc_info_read(entry->private_data, buffer);
 390 }
 391
 392 static void snd_pcm_substream_proc_hw_params_read(struct snd_info_entry *entry,
 393                                                   struct snd_info_buffer *buffer)
 394 {
 395         struct snd_pcm_substream *substream = entry->private_data;
 396         struct snd_pcm_runtime *runtime;
 397
 398         mutex_lock(&substream->pcm->open_mutex);
 399         runtime = substream->runtime;
 400         if (!runtime) {
 401                 snd_iprintf(buffer, "closed\n");
 402                 goto unlock;
 403         }
 404         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 405                 snd_iprintf(buffer, "no setup\n");
 406                 goto unlock;
 407         }
 408         snd_iprintf(buffer, "access: %s\n", snd_pcm_access_name(runtime->access));
 409         snd_iprintf(buffer, "format: %s\n", snd_pcm_format_name(runtime->format));
 410         snd_iprintf(buffer, "subformat: %s\n", snd_pcm_subformat_name(runtime->subformat));
 411         snd_iprintf(buffer, "channels: %u\n", runtime->channels);
 412         snd_iprintf(buffer, "rate: %u (%u/%u)\n", runtime->rate, runtime->rate_num, runtime->rate_den);
 413         snd_iprintf(buffer, "period_size: %lu\n", runtime->period_size);
 414         snd_iprintf(buffer, "buffer_size: %lu\n", runtime->buffer_size);
 415 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 416         if (substream->oss.oss) {
 417                 snd_iprintf(buffer, "OSS format: %s\n", snd_pcm_oss_format_name(runtime->oss.format));
 418                 snd_iprintf(buffer, "OSS channels: %u\n", runtime->oss.channels);
 419                 snd_iprintf(buffer, "OSS rate: %u\n", runtime->oss.rate);
 420                 snd_iprintf(buffer, "OSS period bytes: %lu\n", (unsigned long)runtime->oss.period_bytes);
 421                 snd_iprintf(buffer, "OSS periods: %u\n", runtime->oss.periods);
 422                 snd_iprintf(buffer, "OSS period frames: %lu\n", (unsigned long)runtime->oss.period_frames);
 423         }
 424 #endif
 425  unlock:
 426         mutex_unlock(&substream->pcm->open_mutex);
 427 }
 428
 429 static void snd_pcm_substream_proc_sw_params_read(struct snd_info_entry *entry,
 430                                                   struct snd_info_buffer *buffer)
 431 {
 432         struct snd_pcm_substream *substream = entry->private_data;
 433         struct snd_pcm_runtime *runtime;
 434
 435         mutex_lock(&substream->pcm->open_mutex);
 436         runtime = substream->runtime;
 437         if (!runtime) {
 438                 snd_iprintf(buffer, "closed\n");
 439                 goto unlock;
 440         }
 441         if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 442                 snd_iprintf(buffer, "no setup\n");
 443                 goto unlock;
 444         }
 445         snd_iprintf(buffer, "tstamp_mode: %s\n", snd_pcm_tstamp_mode_name(runtime->tstamp_mode));
 446         snd_iprintf(buffer, "period_step: %u\n", runtime->period_step);
 447         snd_iprintf(buffer, "avail_min: %lu\n", runtime->control->avail_min);
 448         snd_iprintf(buffer, "start_threshold: %lu\n", runtime->start_threshold);
 449         snd_iprintf(buffer, "stop_threshold: %lu\n", runtime->stop_threshold);
 450         snd_iprintf(buffer, "silence_threshold: %lu\n", runtime->silence_threshold);
 451         snd_iprintf(buffer, "silence_size: %lu\n", runtime->silence_size);
 452         snd_iprintf(buffer, "boundary: %lu\n", runtime->boundary);
 453  unlock:
 454         mutex_unlock(&substream->pcm->open_mutex);
 455 }
 456
 457 static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
 458                                                struct snd_info_buffer *buffer)
 459 {
 460         struct snd_pcm_substream *substream = entry->private_data;
 461         struct snd_pcm_runtime *runtime;
 462         struct snd_pcm_status status;
 463         int err;
 464
 465         mutex_lock(&substream->pcm->open_mutex);
 466         runtime = substream->runtime;
 467         if (!runtime) {
 468                 snd_iprintf(buffer, "closed\n");
 469                 goto unlock;
 470         }
 471         memset(&status, 0, sizeof(status));
 472         err = snd_pcm_status(substream, &status);
 473         if (err < 0) {
 474                 snd_iprintf(buffer, "error %d\n", err);
 475                 goto unlock;
 476         }
 477         snd_iprintf(buffer, "state: %s\n", snd_pcm_state_name(status.state));
 478         snd_iprintf(buffer, "owner_pid   : %d\n", pid_vnr(substream->pid));
 479         snd_iprintf(buffer, "trigger_time: %ld.%09ld\n",
 480                 status.trigger_tstamp.tv_sec, status.trigger_tstamp.tv_nsec);
 481         snd_iprintf(buffer, "tstamp      : %ld.%09ld\n",
 482                 status.tstamp.tv_sec, status.tstamp.tv_nsec);
 483         snd_iprintf(buffer, "delay       : %ld\n", status.delay);
 484         snd_iprintf(buffer, "avail       : %ld\n", status.avail);
 485         snd_iprintf(buffer, "avail_max   : %ld\n", status.avail_max);
 486         snd_iprintf(buffer, "-----\n");
 487         snd_iprintf(buffer, "hw_ptr      : %ld\n", runtime->status->hw_ptr);
 488         snd_iprintf(buffer, "appl_ptr    : %ld\n", runtime->control->appl_ptr);
 489  unlock:
 490         mutex_unlock(&substream->pcm->open_mutex);
 491 }
 492
 493 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 494 static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
 495                                          struct snd_info_buffer *buffer)
 496 {
 497         struct snd_pcm_substream *substream = entry->private_data;
 498
 499         snd_pcm_stop_xrun(substream);
 500 }
 501
 502 static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
 503                                     struct snd_info_buffer *buffer)
 504 {
 505         struct snd_pcm_str *pstr = entry->private_data;
 506         snd_iprintf(buffer, "%d\n", pstr->xrun_debug);
 507 }
 508
 509 static void snd_pcm_xrun_debug_write(struct snd_info_entry *entry,
 510                                      struct snd_info_buffer *buffer)
 511 {
 512         struct snd_pcm_str *pstr = entry->private_data;
 513         char line[64];
 514         if (!snd_info_get_line(buffer, line, sizeof(line)))
 515                 pstr->xrun_debug = simple_strtoul(line, NULL, 10);
 516 }
 517 #endif
 518
 519 static int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr)
 520 {
 521         struct snd_pcm *pcm = pstr->pcm;
 522         struct snd_info_entry *entry;
 523         char name[16];
 524
 525         sprintf(name, "pcm%i%c", pcm->device,
 526                 pstr->stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 527         entry = snd_info_create_card_entry(pcm->card, name,
 528                                            pcm->card->proc_root);
 529         if (!entry)
 530                 return -ENOMEM;
 531         entry->mode = S_IFDIR | 0555;
 532         if (snd_info_register(entry) < 0) {
 533                 snd_info_free_entry(entry);
 534                 return -ENOMEM;
 535         }
 536         pstr->proc_root = entry;
 537         entry = snd_info_create_card_entry(pcm->card, "info", pstr->proc_root);
 538         if (entry) {
 539                 snd_info_set_text_ops(entry, pstr, snd_pcm_stream_proc_info_read);
 540                 if (snd_info_register(entry) < 0) {
 541                         snd_info_free_entry(entry);
 542                         entry = NULL;
 543                 }
 544         }
 545         pstr->proc_info_entry = entry;
 546
 547 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 548         entry = snd_info_create_card_entry(pcm->card, "xrun_debug",
 549                                            pstr->proc_root);
 550         if (entry) {
 551                 entry->c.text.read = snd_pcm_xrun_debug_read;
 552                 entry->c.text.write = snd_pcm_xrun_debug_write;
 553                 entry->mode |= 0200;
 554                 entry->private_data = pstr;
 555                 if (snd_info_register(entry) < 0) {
 556                         snd_info_free_entry(entry);
 557                         entry = NULL;
 558                 }
 559         }
 560         pstr->proc_xrun_debug_entry = entry;
 561 #endif
 562         return 0;
 563 }
 564
 565 static int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr)
 566 {
 567 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 568         snd_info_free_entry(pstr->proc_xrun_debug_entry);
 569         pstr->proc_xrun_debug_entry = NULL;
 570 #endif
 571         snd_info_free_entry(pstr->proc_info_entry);
 572         pstr->proc_info_entry = NULL;
 573         snd_info_free_entry(pstr->proc_root);
 574         pstr->proc_root = NULL;
 575         return 0;
 576 }
 577
 578 static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
 579 {
 580         struct snd_info_entry *entry;
 581         struct snd_card *card;
 582         char name[16];
 583
 584         card = substream->pcm->card;
 585
 586         sprintf(name, "sub%i", substream->number);
 587         entry = snd_info_create_card_entry(card, name,
 588                                            substream->pstr->proc_root);
 589         if (!entry)
 590                 return -ENOMEM;
 591         entry->mode = S_IFDIR | 0555;
 592         if (snd_info_register(entry) < 0) {
 593                 snd_info_free_entry(entry);
 594                 return -ENOMEM;
 595         }
 596         substream->proc_root = entry;
 597         entry = snd_info_create_card_entry(card, "info", substream->proc_root);
 598         if (entry) {
 599                 snd_info_set_text_ops(entry, substream,
 600                                       snd_pcm_substream_proc_info_read);
 601                 if (snd_info_register(entry) < 0) {
 602                         snd_info_free_entry(entry);
 603                         entry = NULL;
 604                 }
 605         }
 606         substream->proc_info_entry = entry;
 607         entry = snd_info_create_card_entry(card, "hw_params",
 608                                            substream->proc_root);
 609         if (entry) {
 610                 snd_info_set_text_ops(entry, substream,
 611                                       snd_pcm_substream_proc_hw_params_read);
 612                 if (snd_info_register(entry) < 0) {
 613                         snd_info_free_entry(entry);
 614                         entry = NULL;
 615                 }
 616         }
 617         substream->proc_hw_params_entry = entry;
 618         entry = snd_info_create_card_entry(card, "sw_params",
 619                                            substream->proc_root);
 620         if (entry) {
 621                 snd_info_set_text_ops(entry, substream,
 622                                       snd_pcm_substream_proc_sw_params_read);
 623                 if (snd_info_register(entry) < 0) {
 624                         snd_info_free_entry(entry);
 625                         entry = NULL;
 626                 }
 627         }
 628         substream->proc_sw_params_entry = entry;
 629         entry = snd_info_create_card_entry(card, "status",
 630                                            substream->proc_root);
 631         if (entry) {
 632                 snd_info_set_text_ops(entry, substream,
 633                                       snd_pcm_substream_proc_status_read);
 634                 if (snd_info_register(entry) < 0) {
 635                         snd_info_free_entry(entry);
 636                         entry = NULL;
 637                 }
 638         }
 639         substream->proc_status_entry = entry;
 640
 641 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 642         entry = snd_info_create_card_entry(card, "xrun_injection",
 643                                            substream->proc_root);
 644         if (entry) {
 645                 entry->private_data = substream;
 646                 entry->c.text.read = NULL;
 647                 entry->c.text.write = snd_pcm_xrun_injection_write;
 648                 entry->mode = S_IFREG | 0200;
 649                 if (snd_info_register(entry) < 0) {
 650                         snd_info_free_entry(entry);
 651                         entry = NULL;
 652                 }
 653         }
 654         substream->proc_xrun_injection_entry = entry;
 655 #endif /* CONFIG_SND_PCM_XRUN_DEBUG */
 656
 657         return 0;
 658 }
 659
 660 static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
 661 {
 662         snd_info_free_entry(substream->proc_info_entry);
 663         substream->proc_info_entry = NULL;
 664         snd_info_free_entry(substream->proc_hw_params_entry);
 665         substream->proc_hw_params_entry = NULL;
 666         snd_info_free_entry(substream->proc_sw_params_entry);
 667         substream->proc_sw_params_entry = NULL;
 668         snd_info_free_entry(substream->proc_status_entry);
 669         substream->proc_status_entry = NULL;
 670 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 671         snd_info_free_entry(substream->proc_xrun_injection_entry);
 672         substream->proc_xrun_injection_entry = NULL;
 673 #endif
 674         snd_info_free_entry(substream->proc_root);
 675         substream->proc_root = NULL;
 676         return 0;
 677 }
 678 #else /* !CONFIG_SND_VERBOSE_PROCFS */
 679 static inline int snd_pcm_stream_proc_init(struct snd_pcm_str *pstr) { return 0; }
 680 static inline int snd_pcm_stream_proc_done(struct snd_pcm_str *pstr) { return 0; }
 681 static inline int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream) { return 0; }
 682 static inline int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream) { return 0; }
 683 #endif /* CONFIG_SND_VERBOSE_PROCFS */
 684
 685 static const struct attribute_group *pcm_dev_attr_groups[];
 686
 687 /**
 688  * snd_pcm_new_stream - create a new PCM stream
 689  * @pcm: the pcm instance
 690  * @stream: the stream direction, SNDRV_PCM_STREAM_XXX
 691  * @substream_count: the number of substreams
 692  *
 693  * Creates a new stream for the pcm.
 694  * The corresponding stream on the pcm must have been empty before
 695  * calling this, i.e. zero must be given to the argument of
 696  * snd_pcm_new().
 697  *
 698  * Return: Zero if successful, or a negative error code on failure.
 699  */
 700 int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 701 {
 702         int idx, err;
 703         struct snd_pcm_str *pstr = &pcm->streams[stream];
 704         struct snd_pcm_substream *substream, *prev;
 705
 706 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
 707         mutex_init(&pstr->oss.setup_mutex);
 708 #endif
 709         pstr->stream = stream;
 710         pstr->pcm = pcm;
 711         pstr->substream_count = substream_count;
 712         if (!substream_count)
 713                 return 0;
 714
 715         snd_device_initialize(&pstr->dev, pcm->card);
 716         pstr->dev.groups = pcm_dev_attr_groups;
 717         dev_set_name(&pstr->dev, "pcmC%iD%i%c", pcm->card->number, pcm->device,
 718                      stream == SNDRV_PCM_STREAM_PLAYBACK ? 'p' : 'c');
 719
 720         if (!pcm->internal) {
 721                 err = snd_pcm_stream_proc_init(pstr);
 722                 if (err < 0) {
 723                         pcm_err(pcm, "Error in snd_pcm_stream_proc_init\n");
 724                         return err;
 725                 }
 726         }
 727         prev = NULL;
 728         for (idx = 0, prev = NULL; idx < substream_count; idx++) {
 729                 substream = kzalloc(sizeof(*substream), GFP_KERNEL);
 730                 if (!substream)
 731                         return -ENOMEM;
 732                 substream->pcm = pcm;
 733                 substream->pstr = pstr;
 734                 substream->number = idx;
 735                 substream->stream = stream;
 736                 sprintf(substream->name, "subdevice #%i", idx);
 737                 substream->buffer_bytes_max = UINT_MAX;
 738                 if (prev == NULL)
 739                         pstr->substream = substream;
 740                 else
 741                         prev->next = substream;
 742
 743                 if (!pcm->internal) {
 744                         err = snd_pcm_substream_proc_init(substream);
 745                         if (err < 0) {
 746                                 pcm_err(pcm,
 747                                         "Error in snd_pcm_stream_proc_init\n");
 748                                 if (prev == NULL)
 749                                         pstr->substream = NULL;
 750                                 else
 751                                         prev->next = NULL;
 752                                 kfree(substream);
 753                                 return err;
 754                         }
 755                 }
 756                 substream->group = &substream->self_group;
 757                 spin_lock_init(&substream->self_group.lock);
 758                 mutex_init(&substream->self_group.mutex);
 759                 INIT_LIST_HEAD(&substream->self_group.substreams);
 760                 list_add_tail(&substream->link_list, &substream->self_group.substreams);
 761                 atomic_set(&substream->mmap_count, 0);
 762                 prev = substream;
 763         }
 764         return 0;
 765 }
 766 EXPORT_SYMBOL(snd_pcm_new_stream);
 767
 768 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
 769                 int playback_count, int capture_count, bool internal,
 770                 struct snd_pcm **rpcm)
 771 {
 772         struct snd_pcm *pcm;
 773         int err;
 774         static struct snd_device_ops ops = {
 775                 .dev_free = snd_pcm_dev_free,
 776                 .dev_register = snd_pcm_dev_register,
 777                 .dev_disconnect = snd_pcm_dev_disconnect,
 778         };
 779         static struct snd_device_ops internal_ops = {
 780                 .dev_free = snd_pcm_dev_free,
 781         };
 782
 783         if (snd_BUG_ON(!card))
 784                 return -ENXIO;
 785         if (rpcm)
 786                 *rpcm = NULL;
 787         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 788         if (!pcm)
 789                 return -ENOMEM;
 790         pcm->card = card;
 791         pcm->device = device;
 792         pcm->internal = internal;
 793         mutex_init(&pcm->open_mutex);
 794         init_waitqueue_head(&pcm->open_wait);
 795         INIT_LIST_HEAD(&pcm->list);
 796         if (id)
 797                 strlcpy(pcm->id, id, sizeof(pcm->id));
 798
 799         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK,
 800                                  playback_count);
 801         if (err < 0)
 802                 goto free_pcm;
 803
 804         err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_CAPTURE, capture_count);
 805         if (err < 0)
 806                 goto free_pcm;
 807
 808         err = snd_device_new(card, SNDRV_DEV_PCM, pcm,
 809                              internal ? &internal_ops : &ops);
 810         if (err < 0)
 811                 goto free_pcm;
 812
 813         if (rpcm)
 814                 *rpcm = pcm;
 815         return 0;
 816
 817 free_pcm:
 818         snd_pcm_free(pcm);
 819         return err;
 820 }
 821
 822 /**
 823  * snd_pcm_new - create a new PCM instance
 824  * @card: the card instance
 825  * @id: the id string
 826  * @device: the device index (zero based)
 827  * @playback_count: the number of substreams for playback
 828  * @capture_count: the number of substreams for capture
 829  * @rpcm: the pointer to store the new pcm instance
 830  *
 831  * Creates a new PCM instance.
 832  *
 833  * The pcm operators have to be set afterwards to the new instance
 834  * via snd_pcm_set_ops().
 835  *
 836  * Return: Zero if successful, or a negative error code on failure.
 837  */
 838 int snd_pcm_new(struct snd_card *card, const char *id, int device,
 839                 int playback_count, int capture_count, struct snd_pcm **rpcm)
 840 {
 841         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 842                         false, rpcm);
 843 }
 844 EXPORT_SYMBOL(snd_pcm_new);
 845
 846 /**
 847  * snd_pcm_new_internal - create a new internal PCM instance
 848  * @card: the card instance
 849  * @id: the id string
 850  * @device: the device index (zero based - shared with normal PCMs)
 851  * @playback_count: the number of substreams for playback
 852  * @capture_count: the number of substreams for capture
 853  * @rpcm: the pointer to store the new pcm instance
 854  *
 855  * Creates a new internal PCM instance with no userspace device or procfs
 856  * entries. This is used by ASoC Back End PCMs in order to create a PCM that
 857  * will only be used internally by kernel drivers. i.e. it cannot be opened
 858  * by userspace. It provides existing ASoC components drivers with a substream
 859  * and access to any private data.
 860  *
 861  * The pcm operators have to be set afterwards to the new instance
 862  * via snd_pcm_set_ops().
 863  *
 864  * Return: Zero if successful, or a negative error code on failure.
 865  */
 866 int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
 867         int playback_count, int capture_count,
 868         struct snd_pcm **rpcm)
 869 {
 870         return _snd_pcm_new(card, id, device, playback_count, capture_count,
 871                         true, rpcm);
 872 }
 873 EXPORT_SYMBOL(snd_pcm_new_internal);
 874
 875 static void free_chmap(struct snd_pcm_str *pstr)
 876 {
 877         if (pstr->chmap_kctl) {
 878                 struct snd_card *card = pstr->pcm->card;
 879
 880                 down_write(&card->controls_rwsem);
 881                 snd_ctl_remove(card, pstr->chmap_kctl);
 882                 up_write(&card->controls_rwsem);
 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         mutex_init(&runtime->buffer_mutex);
1036         atomic_set(&runtime->buffer_accessing, 0);
1037
1038         substream->runtime = runtime;
1039         substream->private_data = pcm->private_data;
1040         substream->ref_count = 1;
1041         substream->f_flags = file->f_flags;
1042         substream->pid = get_pid(task_pid(current));
1043         pstr->substream_opened++;
1044         *rsubstream = substream;
1045         return 0;
1046 }
1047
1048 void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
1049 {
1050         struct snd_pcm_runtime *runtime;
1051
1052         if (PCM_RUNTIME_CHECK(substream))
1053                 return;
1054         runtime = substream->runtime;
1055         if (runtime->private_free != NULL)
1056                 runtime->private_free(runtime);
1057         snd_free_pages((void*)runtime->status,
1058                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)));
1059         snd_free_pages((void*)runtime->control,
1060                        PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)));
1061         kfree(runtime->hw_constraints.rules);
1062         /* Avoid concurrent access to runtime via PCM timer interface */
1063         if (substream->timer)
1064                 spin_lock_irq(&substream->timer->lock);
1065         substream->runtime = NULL;
1066         if (substream->timer)
1067                 spin_unlock_irq(&substream->timer->lock);
1068         mutex_destroy(&runtime->buffer_mutex);
1069         kfree(runtime);
1070         put_pid(substream->pid);
1071         substream->pid = NULL;
1072         substream->pstr->substream_opened--;
1073 }
1074
1075 static ssize_t show_pcm_class(struct device *dev,
1076                               struct device_attribute *attr, char *buf)
1077 {
1078         struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
1079         struct snd_pcm *pcm = pstr->pcm;
1080         const char *str;
1081         static const char *strs[SNDRV_PCM_CLASS_LAST + 1] = {
1082                 [SNDRV_PCM_CLASS_GENERIC] = "generic",
1083                 [SNDRV_PCM_CLASS_MULTI] = "multi",
1084                 [SNDRV_PCM_CLASS_MODEM] = "modem",
1085                 [SNDRV_PCM_CLASS_DIGITIZER] = "digitizer",
1086         };
1087
1088         if (pcm->dev_class > SNDRV_PCM_CLASS_LAST)
1089                 str = "none";
1090         else
1091                 str = strs[pcm->dev_class];
1092         return snprintf(buf, PAGE_SIZE, "%s\n", str);
1093 }
1094
1095 static DEVICE_ATTR(pcm_class, 0444, show_pcm_class, NULL);
1096 static struct attribute *pcm_dev_attrs[] = {
1097         &dev_attr_pcm_class.attr,
1098         NULL
1099 };
1100
1101 static const struct attribute_group pcm_dev_attr_group = {
1102         .attrs  = pcm_dev_attrs,
1103 };
1104
1105 static const struct attribute_group *pcm_dev_attr_groups[] = {
1106         &pcm_dev_attr_group,
1107         NULL
1108 };
1109
1110 static int snd_pcm_dev_register(struct snd_device *device)
1111 {
1112         int cidx, err;
1113         struct snd_pcm_substream *substream;
1114         struct snd_pcm *pcm;
1115
1116         if (snd_BUG_ON(!device || !device->device_data))
1117                 return -ENXIO;
1118         pcm = device->device_data;
1119
1120         mutex_lock(&register_mutex);
1121         err = snd_pcm_add(pcm);
1122         if (err)
1123                 goto unlock;
1124         for (cidx = 0; cidx < 2; cidx++) {
1125                 int devtype = -1;
1126                 if (pcm->streams[cidx].substream == NULL)
1127                         continue;
1128                 switch (cidx) {
1129                 case SNDRV_PCM_STREAM_PLAYBACK:
1130                         devtype = SNDRV_DEVICE_TYPE_PCM_PLAYBACK;
1131                         break;
1132                 case SNDRV_PCM_STREAM_CAPTURE:
1133                         devtype = SNDRV_DEVICE_TYPE_PCM_CAPTURE;
1134                         break;
1135                 }
1136                 /* register pcm */
1137                 err = snd_register_device(devtype, pcm->card, pcm->device,
1138                                           &snd_pcm_f_ops[cidx], pcm,
1139                                           &pcm->streams[cidx].dev);
1140                 if (err < 0) {
1141                         list_del_init(&pcm->list);
1142                         goto unlock;
1143                 }
1144
1145                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next)
1146                         snd_pcm_timer_init(substream);
1147         }
1148
1149         pcm_call_notify(pcm, n_register);
1150
1151  unlock:
1152         mutex_unlock(&register_mutex);
1153         return err;
1154 }
1155
1156 static int snd_pcm_dev_disconnect(struct snd_device *device)
1157 {
1158         struct snd_pcm *pcm = device->device_data;
1159         struct snd_pcm_substream *substream;
1160         int cidx;
1161
1162         mutex_lock(&register_mutex);
1163         mutex_lock(&pcm->open_mutex);
1164         wake_up(&pcm->open_wait);
1165         list_del_init(&pcm->list);
1166         for (cidx = 0; cidx < 2; cidx++) {
1167                 for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) {
1168                         snd_pcm_stream_lock_irq(substream);
1169                         if (substream->runtime) {
1170                                 if (snd_pcm_running(substream))
1171                                         snd_pcm_stop(substream,
1172                                                      SNDRV_PCM_STATE_DISCONNECTED);
1173                                 /* to be sure, set the state unconditionally */
1174                                 substream->runtime->status->state = SNDRV_PCM_STATE_DISCONNECTED;
1175                                 wake_up(&substream->runtime->sleep);
1176                                 wake_up(&substream->runtime->tsleep);
1177                         }
1178                         snd_pcm_stream_unlock_irq(substream);
1179                 }
1180         }
1181
1182         pcm_call_notify(pcm, n_disconnect);
1183         for (cidx = 0; cidx < 2; cidx++) {
1184                 snd_unregister_device(&pcm->streams[cidx].dev);
1185                 free_chmap(&pcm->streams[cidx]);
1186         }
1187         mutex_unlock(&pcm->open_mutex);
1188         mutex_unlock(&register_mutex);
1189         return 0;
1190 }
1191
1192 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
1193 /**
1194  * snd_pcm_notify - Add/remove the notify list
1195  * @notify: PCM notify list
1196  * @nfree: 0 = register, 1 = unregister
1197  *
1198  * This adds the given notifier to the global list so that the callback is
1199  * called for each registered PCM devices.  This exists only for PCM OSS
1200  * emulation, so far.
1201  */
1202 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
1203 {
1204         struct snd_pcm *pcm;
1205
1206         if (snd_BUG_ON(!notify ||
1207                        !notify->n_register ||
1208                        !notify->n_unregister ||
1209                        !notify->n_disconnect))
1210                 return -EINVAL;
1211         mutex_lock(&register_mutex);
1212         if (nfree) {
1213                 list_del(&notify->list);
1214                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1215                         notify->n_unregister(pcm);
1216         } else {
1217                 list_add_tail(&notify->list, &snd_pcm_notify_list);
1218                 list_for_each_entry(pcm, &snd_pcm_devices, list)
1219                         notify->n_register(pcm);
1220         }
1221         mutex_unlock(&register_mutex);
1222         return 0;
1223 }
1224 EXPORT_SYMBOL(snd_pcm_notify);
1225 #endif /* CONFIG_SND_PCM_OSS */
1226
1227 #ifdef CONFIG_SND_PROC_FS
1228 /*
1229  *  Info interface
1230  */
1231
1232 static void snd_pcm_proc_read(struct snd_info_entry *entry,
1233                               struct snd_info_buffer *buffer)
1234 {
1235         struct snd_pcm *pcm;
1236
1237         mutex_lock(&register_mutex);
1238         list_for_each_entry(pcm, &snd_pcm_devices, list) {
1239                 snd_iprintf(buffer, "%02i-%02i: %s : %s",
1240                             pcm->card->number, pcm->device, pcm->id, pcm->name);
1241                 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
1242                         snd_iprintf(buffer, " : playback %i",
1243                                     pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream_count);
1244                 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream)
1245                         snd_iprintf(buffer, " : capture %i",
1246                                     pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count);
1247                 snd_iprintf(buffer, "\n");
1248         }
1249         mutex_unlock(&register_mutex);
1250 }
1251
1252 static struct snd_info_entry *snd_pcm_proc_entry;
1253
1254 static void snd_pcm_proc_init(void)
1255 {
1256         struct snd_info_entry *entry;
1257
1258         entry = snd_info_create_module_entry(THIS_MODULE, "pcm", NULL);
1259         if (entry) {
1260                 snd_info_set_text_ops(entry, NULL, snd_pcm_proc_read);
1261                 if (snd_info_register(entry) < 0) {
1262                         snd_info_free_entry(entry);
1263                         entry = NULL;
1264                 }
1265         }
1266         snd_pcm_proc_entry = entry;
1267 }
1268
1269 static void snd_pcm_proc_done(void)
1270 {
1271         snd_info_free_entry(snd_pcm_proc_entry);
1272 }
1273
1274 #else /* !CONFIG_SND_PROC_FS */
1275 #define snd_pcm_proc_init()
1276 #define snd_pcm_proc_done()
1277 #endif /* CONFIG_SND_PROC_FS */
1278
1279
1280 /*
1281  *  ENTRY functions
1282  */
1283
1284 static int __init alsa_pcm_init(void)
1285 {
1286         snd_ctl_register_ioctl(snd_pcm_control_ioctl);
1287         snd_ctl_register_ioctl_compat(snd_pcm_control_ioctl);
1288         snd_pcm_proc_init();
1289         return 0;
1290 }
1291
1292 static void __exit alsa_pcm_exit(void)
1293 {
1294         snd_ctl_unregister_ioctl(snd_pcm_control_ioctl);
1295         snd_ctl_unregister_ioctl_compat(snd_pcm_control_ioctl);
1296         snd_pcm_proc_done();
1297 }
1298
1299 module_init(alsa_pcm_init)
1300 module_exit(alsa_pcm_exit)