sound/core/compress_offload.c

   1 /*
   2  *  compress_core.c - compress offload core
   3  *
   4  *  Copyright (C) 2011 Intel Corporation
   5  *  Authors:    Vinod Koul <[email protected]>
   6  *              Pierre-Louis Bossart <[email protected]>
   7  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; version 2 of the License.
  12  *
  13  *  This program is distributed in the hope that it will be useful, but
  14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *  General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License along
  19  *  with this program; if not, write to the Free Software Foundation, Inc.,
  20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  21  *
  22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  23  *
  24  */
  25 #define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
  26 #define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
  27
  28 #include <linux/file.h>
  29 #include <linux/fs.h>
  30 #include <linux/list.h>
  31 #include <linux/math64.h>
  32 #include <linux/mm.h>
  33 #include <linux/mutex.h>
  34 #include <linux/poll.h>
  35 #include <linux/slab.h>
  36 #include <linux/sched.h>
  37 #include <linux/types.h>
  38 #include <linux/uio.h>
  39 #include <linux/uaccess.h>
  40 #include <linux/module.h>
  41 #include <linux/compat.h>
  42 #include <sound/core.h>
  43 #include <sound/initval.h>
  44 #include <sound/info.h>
  45 #include <sound/compress_params.h>
  46 #include <sound/compress_offload.h>
  47 #include <sound/compress_driver.h>
  48
  49 /* TODO:
  50  * - add substream support for multiple devices in case of
  51  *      SND_DYNAMIC_MINORS is not used
  52  * - Multiple node representation
  53  *      driver should be able to register multiple nodes
  54  */
  55
  56 static DEFINE_MUTEX(device_mutex);
  57
  58 struct snd_compr_file {
  59         unsigned long caps;
  60         struct snd_compr_stream stream;
  61 };
  62
  63 /*
  64  * a note on stream states used:
  65  * we use follwing states in the compressed core
  66  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
  67  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
  68  *      calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
  69  *      state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
  70  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
  71  *      decoding/encoding and rendering/capturing data.
  72  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
  73  *      by calling SNDRV_COMPRESS_DRAIN.
  74  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
  75  *      SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
  76  *      SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
  77  */
  78 static int snd_compr_open(struct inode *inode, struct file *f)
  79 {
  80         struct snd_compr *compr;
  81         struct snd_compr_file *data;
  82         struct snd_compr_runtime *runtime;
  83         enum snd_compr_direction dirn;
  84         int maj = imajor(inode);
  85         int ret;
  86
  87         if ((f->f_flags & O_ACCMODE) == O_WRONLY)
  88                 dirn = SND_COMPRESS_PLAYBACK;
  89         else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
  90                 dirn = SND_COMPRESS_CAPTURE;
  91         else
  92                 return -EINVAL;
  93
  94         if (maj == snd_major)
  95                 compr = snd_lookup_minor_data(iminor(inode),
  96                                         SNDRV_DEVICE_TYPE_COMPRESS);
  97         else
  98                 return -EBADFD;
  99
 100         if (compr == NULL) {
 101                 pr_err("no device data!!!\n");
 102                 return -ENODEV;
 103         }
 104
 105         if (dirn != compr->direction) {
 106                 pr_err("this device doesn't support this direction\n");
 107                 snd_card_unref(compr->card);
 108                 return -EINVAL;
 109         }
 110
 111         data = kzalloc(sizeof(*data), GFP_KERNEL);
 112         if (!data) {
 113                 snd_card_unref(compr->card);
 114                 return -ENOMEM;
 115         }
 116         data->stream.ops = compr->ops;
 117         data->stream.direction = dirn;
 118         data->stream.private_data = compr->private_data;
 119         data->stream.device = compr;
 120         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 121         if (!runtime) {
 122                 kfree(data);
 123                 snd_card_unref(compr->card);
 124                 return -ENOMEM;
 125         }
 126         runtime->state = SNDRV_PCM_STATE_OPEN;
 127         init_waitqueue_head(&runtime->sleep);
 128         data->stream.runtime = runtime;
 129         f->private_data = (void *)data;
 130         mutex_lock(&compr->lock);
 131         ret = compr->ops->open(&data->stream);
 132         mutex_unlock(&compr->lock);
 133         if (ret) {
 134                 kfree(runtime);
 135                 kfree(data);
 136         }
 137         snd_card_unref(compr->card);
 138         return ret;
 139 }
 140
 141 static int snd_compr_free(struct inode *inode, struct file *f)
 142 {
 143         struct snd_compr_file *data = f->private_data;
 144         struct snd_compr_runtime *runtime = data->stream.runtime;
 145
 146         switch (runtime->state) {
 147         case SNDRV_PCM_STATE_RUNNING:
 148         case SNDRV_PCM_STATE_DRAINING:
 149         case SNDRV_PCM_STATE_PAUSED:
 150                 data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
 151                 break;
 152         default:
 153                 break;
 154         }
 155
 156         data->stream.ops->free(&data->stream);
 157         kfree(data->stream.runtime->buffer);
 158         kfree(data->stream.runtime);
 159         kfree(data);
 160         return 0;
 161 }
 162
 163 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 164                 struct snd_compr_tstamp *tstamp)
 165 {
 166         if (!stream->ops->pointer)
 167                 return -ENOTSUPP;
 168         stream->ops->pointer(stream, tstamp);
 169         pr_debug("dsp consumed till %d total %d bytes\n",
 170                 tstamp->byte_offset, tstamp->copied_total);
 171         if (stream->direction == SND_COMPRESS_PLAYBACK)
 172                 stream->runtime->total_bytes_transferred = tstamp->copied_total;
 173         else
 174                 stream->runtime->total_bytes_available = tstamp->copied_total;
 175         return 0;
 176 }
 177
 178 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
 179                 struct snd_compr_avail *avail)
 180 {
 181         memset(avail, 0, sizeof(*avail));
 182         snd_compr_update_tstamp(stream, &avail->tstamp);
 183         /* Still need to return avail even if tstamp can't be filled in */
 184
 185         if (stream->runtime->total_bytes_available == 0 &&
 186                         stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
 187                         stream->direction == SND_COMPRESS_PLAYBACK) {
 188                 pr_debug("detected init and someone forgot to do a write\n");
 189                 return stream->runtime->buffer_size;
 190         }
 191         pr_debug("app wrote %lld, DSP consumed %lld\n",
 192                         stream->runtime->total_bytes_available,
 193                         stream->runtime->total_bytes_transferred);
 194         if (stream->runtime->total_bytes_available ==
 195                                 stream->runtime->total_bytes_transferred) {
 196                 if (stream->direction == SND_COMPRESS_PLAYBACK) {
 197                         pr_debug("both pointers are same, returning full avail\n");
 198                         return stream->runtime->buffer_size;
 199                 } else {
 200                         pr_debug("both pointers are same, returning no avail\n");
 201                         return 0;
 202                 }
 203         }
 204
 205         avail->avail = stream->runtime->total_bytes_available -
 206                         stream->runtime->total_bytes_transferred;
 207         if (stream->direction == SND_COMPRESS_PLAYBACK)
 208                 avail->avail = stream->runtime->buffer_size - avail->avail;
 209
 210         pr_debug("ret avail as %lld\n", avail->avail);
 211         return avail->avail;
 212 }
 213
 214 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 215 {
 216         struct snd_compr_avail avail;
 217
 218         return snd_compr_calc_avail(stream, &avail);
 219 }
 220
 221 static int
 222 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
 223 {
 224         struct snd_compr_avail ioctl_avail;
 225         size_t avail;
 226
 227         avail = snd_compr_calc_avail(stream, &ioctl_avail);
 228         ioctl_avail.avail = avail;
 229
 230         if (copy_to_user((__u64 __user *)arg,
 231                                 &ioctl_avail, sizeof(ioctl_avail)))
 232                 return -EFAULT;
 233         return 0;
 234 }
 235
 236 static int snd_compr_write_data(struct snd_compr_stream *stream,
 237                const char __user *buf, size_t count)
 238 {
 239         void *dstn;
 240         size_t copy;
 241         struct snd_compr_runtime *runtime = stream->runtime;
 242         /* 64-bit Modulus */
 243         u64 app_pointer = div64_u64(runtime->total_bytes_available,
 244                                     runtime->buffer_size);
 245         app_pointer = runtime->total_bytes_available -
 246                       (app_pointer * runtime->buffer_size);
 247
 248         dstn = runtime->buffer + app_pointer;
 249         pr_debug("copying %ld at %lld\n",
 250                         (unsigned long)count, app_pointer);
 251         if (count < runtime->buffer_size - app_pointer) {
 252                 if (copy_from_user(dstn, buf, count))
 253                         return -EFAULT;
 254         } else {
 255                 copy = runtime->buffer_size - app_pointer;
 256                 if (copy_from_user(dstn, buf, copy))
 257                         return -EFAULT;
 258                 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
 259                         return -EFAULT;
 260         }
 261         /* if DSP cares, let it know data has been written */
 262         if (stream->ops->ack)
 263                 stream->ops->ack(stream, count);
 264         return count;
 265 }
 266
 267 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
 268                 size_t count, loff_t *offset)
 269 {
 270         struct snd_compr_file *data = f->private_data;
 271         struct snd_compr_stream *stream;
 272         size_t avail;
 273         int retval;
 274
 275         if (snd_BUG_ON(!data))
 276                 return -EFAULT;
 277
 278         stream = &data->stream;
 279         mutex_lock(&stream->device->lock);
 280         /* write is allowed when stream is running or has been steup */
 281         if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 282                         stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 283                 mutex_unlock(&stream->device->lock);
 284                 return -EBADFD;
 285         }
 286
 287         avail = snd_compr_get_avail(stream);
 288         pr_debug("avail returned %ld\n", (unsigned long)avail);
 289         /* calculate how much we can write to buffer */
 290         if (avail > count)
 291                 avail = count;
 292
 293         if (stream->ops->copy) {
 294                 char __user* cbuf = (char __user*)buf;
 295                 retval = stream->ops->copy(stream, cbuf, avail);
 296         } else {
 297                 retval = snd_compr_write_data(stream, buf, avail);
 298         }
 299         if (retval > 0)
 300                 stream->runtime->total_bytes_available += retval;
 301
 302         /* while initiating the stream, write should be called before START
 303          * call, so in setup move state */
 304         if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
 305                 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 306                 pr_debug("stream prepared, Houston we are good to go\n");
 307         }
 308
 309         mutex_unlock(&stream->device->lock);
 310         return retval;
 311 }
 312
 313
 314 static ssize_t snd_compr_read(struct file *f, char __user *buf,
 315                 size_t count, loff_t *offset)
 316 {
 317         struct snd_compr_file *data = f->private_data;
 318         struct snd_compr_stream *stream;
 319         size_t avail;
 320         int retval;
 321
 322         if (snd_BUG_ON(!data))
 323                 return -EFAULT;
 324
 325         stream = &data->stream;
 326         mutex_lock(&stream->device->lock);
 327
 328         /* read is allowed when stream is running, paused, draining and setup
 329          * (yes setup is state which we transition to after stop, so if user
 330          * wants to read data after stop we allow that)
 331          */
 332         switch (stream->runtime->state) {
 333         case SNDRV_PCM_STATE_OPEN:
 334         case SNDRV_PCM_STATE_PREPARED:
 335         case SNDRV_PCM_STATE_XRUN:
 336         case SNDRV_PCM_STATE_SUSPENDED:
 337         case SNDRV_PCM_STATE_DISCONNECTED:
 338                 retval = -EBADFD;
 339                 goto out;
 340         }
 341
 342         avail = snd_compr_get_avail(stream);
 343         pr_debug("avail returned %ld\n", (unsigned long)avail);
 344         /* calculate how much we can read from buffer */
 345         if (avail > count)
 346                 avail = count;
 347
 348         if (stream->ops->copy) {
 349                 retval = stream->ops->copy(stream, buf, avail);
 350         } else {
 351                 retval = -ENXIO;
 352                 goto out;
 353         }
 354         if (retval > 0)
 355                 stream->runtime->total_bytes_transferred += retval;
 356
 357 out:
 358         mutex_unlock(&stream->device->lock);
 359         return retval;
 360 }
 361
 362 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
 363 {
 364         return -ENXIO;
 365 }
 366
 367 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
 368 {
 369         if (stream->direction == SND_COMPRESS_PLAYBACK)
 370                 return POLLOUT | POLLWRNORM;
 371         else
 372                 return POLLIN | POLLRDNORM;
 373 }
 374
 375 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
 376 {
 377         struct snd_compr_file *data = f->private_data;
 378         struct snd_compr_stream *stream;
 379         size_t avail;
 380         int retval = 0;
 381
 382         if (snd_BUG_ON(!data))
 383                 return -EFAULT;
 384         stream = &data->stream;
 385         if (snd_BUG_ON(!stream))
 386                 return -EFAULT;
 387
 388         mutex_lock(&stream->device->lock);
 389         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 390                 retval = -EBADFD;
 391                 goto out;
 392         }
 393         poll_wait(f, &stream->runtime->sleep, wait);
 394
 395         avail = snd_compr_get_avail(stream);
 396         pr_debug("avail is %ld\n", (unsigned long)avail);
 397         /* check if we have at least one fragment to fill */
 398         switch (stream->runtime->state) {
 399         case SNDRV_PCM_STATE_DRAINING:
 400                 /* stream has been woken up after drain is complete
 401                  * draining done so set stream state to stopped
 402                  */
 403                 retval = snd_compr_get_poll(stream);
 404                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 405                 break;
 406         case SNDRV_PCM_STATE_RUNNING:
 407         case SNDRV_PCM_STATE_PREPARED:
 408         case SNDRV_PCM_STATE_PAUSED:
 409                 if (avail >= stream->runtime->fragment_size)
 410                         retval = snd_compr_get_poll(stream);
 411                 break;
 412         default:
 413                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 414                         retval = POLLOUT | POLLWRNORM | POLLERR;
 415                 else
 416                         retval = POLLIN | POLLRDNORM | POLLERR;
 417                 break;
 418         }
 419 out:
 420         mutex_unlock(&stream->device->lock);
 421         return retval;
 422 }
 423
 424 static int
 425 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 426 {
 427         int retval;
 428         struct snd_compr_caps caps;
 429
 430         if (!stream->ops->get_caps)
 431                 return -ENXIO;
 432
 433         memset(&caps, 0, sizeof(caps));
 434         retval = stream->ops->get_caps(stream, &caps);
 435         if (retval)
 436                 goto out;
 437         if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 438                 retval = -EFAULT;
 439 out:
 440         return retval;
 441 }
 442
 443 static int
 444 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 445 {
 446         int retval;
 447         struct snd_compr_codec_caps *caps;
 448
 449         if (!stream->ops->get_codec_caps)
 450                 return -ENXIO;
 451
 452         caps = kzalloc(sizeof(*caps), GFP_KERNEL);
 453         if (!caps)
 454                 return -ENOMEM;
 455
 456         retval = stream->ops->get_codec_caps(stream, caps);
 457         if (retval)
 458                 goto out;
 459         if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 460                 retval = -EFAULT;
 461
 462 out:
 463         kfree(caps);
 464         return retval;
 465 }
 466
 467 /* revisit this with snd_pcm_preallocate_xxx */
 468 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 469                 struct snd_compr_params *params)
 470 {
 471         unsigned int buffer_size;
 472         void *buffer;
 473
 474         buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 475         if (stream->ops->copy) {
 476                 buffer = NULL;
 477                 /* if copy is defined the driver will be required to copy
 478                  * the data from core
 479                  */
 480         } else {
 481                 buffer = kmalloc(buffer_size, GFP_KERNEL);
 482                 if (!buffer)
 483                         return -ENOMEM;
 484         }
 485         stream->runtime->fragment_size = params->buffer.fragment_size;
 486         stream->runtime->fragments = params->buffer.fragments;
 487         stream->runtime->buffer = buffer;
 488         stream->runtime->buffer_size = buffer_size;
 489         return 0;
 490 }
 491
 492 static int snd_compress_check_input(struct snd_compr_params *params)
 493 {
 494         /* first let's check the buffer parameter's */
 495         if (params->buffer.fragment_size == 0 ||
 496             params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
 497                 return -EINVAL;
 498
 499         /* now codec parameters */
 500         if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 501                 return -EINVAL;
 502
 503         if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 504                 return -EINVAL;
 505
 506         return 0;
 507 }
 508
 509 static int
 510 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 511 {
 512         struct snd_compr_params *params;
 513         int retval;
 514
 515         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 516                 /*
 517                  * we should allow parameter change only when stream has been
 518                  * opened not in other cases
 519                  */
 520                 params = kmalloc(sizeof(*params), GFP_KERNEL);
 521                 if (!params)
 522                         return -ENOMEM;
 523                 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 524                         retval = -EFAULT;
 525                         goto out;
 526                 }
 527
 528                 retval = snd_compress_check_input(params);
 529                 if (retval)
 530                         goto out;
 531
 532                 retval = snd_compr_allocate_buffer(stream, params);
 533                 if (retval) {
 534                         retval = -ENOMEM;
 535                         goto out;
 536                 }
 537
 538                 retval = stream->ops->set_params(stream, params);
 539                 if (retval)
 540                         goto out;
 541
 542                 stream->metadata_set = false;
 543                 stream->next_track = false;
 544
 545                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 546                         stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 547                 else
 548                         stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 549         } else {
 550                 return -EPERM;
 551         }
 552 out:
 553         kfree(params);
 554         return retval;
 555 }
 556
 557 static int
 558 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 559 {
 560         struct snd_codec *params;
 561         int retval;
 562
 563         if (!stream->ops->get_params)
 564                 return -EBADFD;
 565
 566         params = kzalloc(sizeof(*params), GFP_KERNEL);
 567         if (!params)
 568                 return -ENOMEM;
 569         retval = stream->ops->get_params(stream, params);
 570         if (retval)
 571                 goto out;
 572         if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 573                 retval = -EFAULT;
 574
 575 out:
 576         kfree(params);
 577         return retval;
 578 }
 579
 580 static int
 581 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 582 {
 583         struct snd_compr_metadata metadata;
 584         int retval;
 585
 586         if (!stream->ops->get_metadata)
 587                 return -ENXIO;
 588
 589         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 590                 return -EFAULT;
 591
 592         retval = stream->ops->get_metadata(stream, &metadata);
 593         if (retval != 0)
 594                 return retval;
 595
 596         if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 597                 return -EFAULT;
 598
 599         return 0;
 600 }
 601
 602 static int
 603 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 604 {
 605         struct snd_compr_metadata metadata;
 606         int retval;
 607
 608         if (!stream->ops->set_metadata)
 609                 return -ENXIO;
 610         /*
 611         * we should allow parameter change only when stream has been
 612         * opened not in other cases
 613         */
 614         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 615                 return -EFAULT;
 616
 617         retval = stream->ops->set_metadata(stream, &metadata);
 618         stream->metadata_set = true;
 619
 620         return retval;
 621 }
 622
 623 static inline int
 624 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 625 {
 626         struct snd_compr_tstamp tstamp = {0};
 627         int ret;
 628
 629         ret = snd_compr_update_tstamp(stream, &tstamp);
 630         if (ret == 0)
 631                 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 632                         &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 633         return ret;
 634 }
 635
 636 static int snd_compr_pause(struct snd_compr_stream *stream)
 637 {
 638         int retval;
 639
 640         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 641                 return -EPERM;
 642         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 643         if (!retval)
 644                 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 645         return retval;
 646 }
 647
 648 static int snd_compr_resume(struct snd_compr_stream *stream)
 649 {
 650         int retval;
 651
 652         if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 653                 return -EPERM;
 654         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 655         if (!retval)
 656                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 657         return retval;
 658 }
 659
 660 static int snd_compr_start(struct snd_compr_stream *stream)
 661 {
 662         int retval;
 663
 664         if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
 665                 return -EPERM;
 666         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 667         if (!retval)
 668                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 669         return retval;
 670 }
 671
 672 static int snd_compr_stop(struct snd_compr_stream *stream)
 673 {
 674         int retval;
 675
 676         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 677                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 678                 return -EPERM;
 679         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 680         if (!retval) {
 681                 snd_compr_drain_notify(stream);
 682                 stream->runtime->total_bytes_available = 0;
 683                 stream->runtime->total_bytes_transferred = 0;
 684         }
 685         return retval;
 686 }
 687
 688 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
 689 {
 690         int ret;
 691
 692         /*
 693          * We are called with lock held. So drop the lock while we wait for
 694          * drain complete notfication from the driver
 695          *
 696          * It is expected that driver will notify the drain completion and then
 697          * stream will be moved to SETUP state, even if draining resulted in an
 698          * error. We can trigger next track after this.
 699          */
 700         stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 701         mutex_unlock(&stream->device->lock);
 702
 703         /* we wait for drain to complete here, drain can return when
 704          * interruption occurred, wait returned error or success.
 705          * For the first two cases we don't do anything different here and
 706          * return after waking up
 707          */
 708
 709         ret = wait_event_interruptible(stream->runtime->sleep,
 710                         (stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
 711         if (ret == -ERESTARTSYS)
 712                 pr_debug("wait aborted by a signal");
 713         else if (ret)
 714                 pr_debug("wait for drain failed with %d\n", ret);
 715
 716
 717         wake_up(&stream->runtime->sleep);
 718         mutex_lock(&stream->device->lock);
 719
 720         return ret;
 721 }
 722
 723 static int snd_compr_drain(struct snd_compr_stream *stream)
 724 {
 725         int retval;
 726
 727         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 728                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 729                 return -EPERM;
 730
 731         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 732         if (retval) {
 733                 pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
 734                 wake_up(&stream->runtime->sleep);
 735                 return retval;
 736         }
 737
 738         return snd_compress_wait_for_drain(stream);
 739 }
 740
 741 static int snd_compr_next_track(struct snd_compr_stream *stream)
 742 {
 743         int retval;
 744
 745         /* only a running stream can transition to next track */
 746         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 747                 return -EPERM;
 748
 749         /* you can signal next track isf this is intended to be a gapless stream
 750          * and current track metadata is set
 751          */
 752         if (stream->metadata_set == false)
 753                 return -EPERM;
 754
 755         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 756         if (retval != 0)
 757                 return retval;
 758         stream->metadata_set = false;
 759         stream->next_track = true;
 760         return 0;
 761 }
 762
 763 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 764 {
 765         int retval;
 766         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 767                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 768                 return -EPERM;
 769         /* stream can be drained only when next track has been signalled */
 770         if (stream->next_track == false)
 771                 return -EPERM;
 772
 773         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 774         if (retval) {
 775                 pr_debug("Partial drain returned failure\n");
 776                 wake_up(&stream->runtime->sleep);
 777                 return retval;
 778         }
 779
 780         stream->next_track = false;
 781         return snd_compress_wait_for_drain(stream);
 782 }
 783
 784 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 785 {
 786         struct snd_compr_file *data = f->private_data;
 787         struct snd_compr_stream *stream;
 788         int retval = -ENOTTY;
 789
 790         if (snd_BUG_ON(!data))
 791                 return -EFAULT;
 792         stream = &data->stream;
 793         if (snd_BUG_ON(!stream))
 794                 return -EFAULT;
 795         mutex_lock(&stream->device->lock);
 796         switch (_IOC_NR(cmd)) {
 797         case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 798                 retval = put_user(SNDRV_COMPRESS_VERSION,
 799                                 (int __user *)arg) ? -EFAULT : 0;
 800                 break;
 801         case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 802                 retval = snd_compr_get_caps(stream, arg);
 803                 break;
 804         case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 805                 retval = snd_compr_get_codec_caps(stream, arg);
 806                 break;
 807         case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 808                 retval = snd_compr_set_params(stream, arg);
 809                 break;
 810         case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 811                 retval = snd_compr_get_params(stream, arg);
 812                 break;
 813         case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 814                 retval = snd_compr_set_metadata(stream, arg);
 815                 break;
 816         case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 817                 retval = snd_compr_get_metadata(stream, arg);
 818                 break;
 819         case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 820                 retval = snd_compr_tstamp(stream, arg);
 821                 break;
 822         case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 823                 retval = snd_compr_ioctl_avail(stream, arg);
 824                 break;
 825         case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 826                 retval = snd_compr_pause(stream);
 827                 break;
 828         case _IOC_NR(SNDRV_COMPRESS_RESUME):
 829                 retval = snd_compr_resume(stream);
 830                 break;
 831         case _IOC_NR(SNDRV_COMPRESS_START):
 832                 retval = snd_compr_start(stream);
 833                 break;
 834         case _IOC_NR(SNDRV_COMPRESS_STOP):
 835                 retval = snd_compr_stop(stream);
 836                 break;
 837         case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 838                 retval = snd_compr_drain(stream);
 839                 break;
 840         case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 841                 retval = snd_compr_partial_drain(stream);
 842                 break;
 843         case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 844                 retval = snd_compr_next_track(stream);
 845                 break;
 846
 847         }
 848         mutex_unlock(&stream->device->lock);
 849         return retval;
 850 }
 851
 852 /* support of 32bit userspace on 64bit platforms */
 853 #ifdef CONFIG_COMPAT
 854 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
 855                                                 unsigned long arg)
 856 {
 857         return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 858 }
 859 #endif
 860
 861 static const struct file_operations snd_compr_file_ops = {
 862                 .owner =        THIS_MODULE,
 863                 .open =         snd_compr_open,
 864                 .release =      snd_compr_free,
 865                 .write =        snd_compr_write,
 866                 .read =         snd_compr_read,
 867                 .unlocked_ioctl = snd_compr_ioctl,
 868 #ifdef CONFIG_COMPAT
 869                 .compat_ioctl = snd_compr_ioctl_compat,
 870 #endif
 871                 .mmap =         snd_compr_mmap,
 872                 .poll =         snd_compr_poll,
 873 };
 874
 875 static int snd_compress_dev_register(struct snd_device *device)
 876 {
 877         int ret = -EINVAL;
 878         char str[16];
 879         struct snd_compr *compr;
 880
 881         if (snd_BUG_ON(!device || !device->device_data))
 882                 return -EBADFD;
 883         compr = device->device_data;
 884
 885         pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
 886                         compr->direction);
 887         /* register compressed device */
 888         ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
 889                                   compr->card, compr->device,
 890                                   &snd_compr_file_ops, compr, &compr->dev);
 891         if (ret < 0) {
 892                 pr_err("snd_register_device failed\n %d", ret);
 893                 return ret;
 894         }
 895         return ret;
 896
 897 }
 898
 899 static int snd_compress_dev_disconnect(struct snd_device *device)
 900 {
 901         struct snd_compr *compr;
 902
 903         compr = device->device_data;
 904         snd_unregister_device(&compr->dev);
 905         return 0;
 906 }
 907
 908 #ifdef CONFIG_SND_VERBOSE_PROCFS
 909 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
 910                                         struct snd_info_buffer *buffer)
 911 {
 912         struct snd_compr *compr = (struct snd_compr *)entry->private_data;
 913
 914         snd_iprintf(buffer, "card: %d\n", compr->card->number);
 915         snd_iprintf(buffer, "device: %d\n", compr->device);
 916         snd_iprintf(buffer, "stream: %s\n",
 917                         compr->direction == SND_COMPRESS_PLAYBACK
 918                                 ? "PLAYBACK" : "CAPTURE");
 919         snd_iprintf(buffer, "id: %s\n", compr->id);
 920 }
 921
 922 static int snd_compress_proc_init(struct snd_compr *compr)
 923 {
 924         struct snd_info_entry *entry;
 925         char name[16];
 926
 927         sprintf(name, "compr%i", compr->device);
 928         entry = snd_info_create_card_entry(compr->card, name,
 929                                            compr->card->proc_root);
 930         if (!entry)
 931                 return -ENOMEM;
 932         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 933         if (snd_info_register(entry) < 0) {
 934                 snd_info_free_entry(entry);
 935                 return -ENOMEM;
 936         }
 937         compr->proc_root = entry;
 938
 939         entry = snd_info_create_card_entry(compr->card, "info",
 940                                            compr->proc_root);
 941         if (entry) {
 942                 snd_info_set_text_ops(entry, compr,
 943                                       snd_compress_proc_info_read);
 944                 if (snd_info_register(entry) < 0) {
 945                         snd_info_free_entry(entry);
 946                         entry = NULL;
 947                 }
 948         }
 949         compr->proc_info_entry = entry;
 950
 951         return 0;
 952 }
 953
 954 static void snd_compress_proc_done(struct snd_compr *compr)
 955 {
 956         snd_info_free_entry(compr->proc_info_entry);
 957         compr->proc_info_entry = NULL;
 958         snd_info_free_entry(compr->proc_root);
 959         compr->proc_root = NULL;
 960 }
 961
 962 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
 963 {
 964         strlcpy(compr->id, id, sizeof(compr->id));
 965 }
 966 #else
 967 static inline int snd_compress_proc_init(struct snd_compr *compr)
 968 {
 969         return 0;
 970 }
 971
 972 static inline void snd_compress_proc_done(struct snd_compr *compr)
 973 {
 974 }
 975
 976 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
 977 {
 978 }
 979 #endif
 980
 981 static int snd_compress_dev_free(struct snd_device *device)
 982 {
 983         struct snd_compr *compr;
 984
 985         compr = device->device_data;
 986         snd_compress_proc_done(compr);
 987         put_device(&compr->dev);
 988         return 0;
 989 }
 990
 991 /*
 992  * snd_compress_new: create new compress device
 993  * @card: sound card pointer
 994  * @device: device number
 995  * @dirn: device direction, should be of type enum snd_compr_direction
 996  * @compr: compress device pointer
 997  */
 998 int snd_compress_new(struct snd_card *card, int device,
 999                         int dirn, const char *id, struct snd_compr *compr)
1000 {
1001         static struct snd_device_ops ops = {
1002                 .dev_free = snd_compress_dev_free,
1003                 .dev_register = snd_compress_dev_register,
1004                 .dev_disconnect = snd_compress_dev_disconnect,
1005         };
1006         int ret;
1007
1008         compr->card = card;
1009         compr->device = device;
1010         compr->direction = dirn;
1011
1012         snd_compress_set_id(compr, id);
1013
1014         snd_device_initialize(&compr->dev, card);
1015         dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1016
1017         ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1018         if (ret == 0)
1019                 snd_compress_proc_init(compr);
1020
1021         return ret;
1022 }
1023 EXPORT_SYMBOL_GPL(snd_compress_new);
1024
1025 static int snd_compress_add_device(struct snd_compr *device)
1026 {
1027         int ret;
1028
1029         if (!device->card)
1030                 return -EINVAL;
1031
1032         /* register the card */
1033         ret = snd_card_register(device->card);
1034         if (ret)
1035                 goto out;
1036         return 0;
1037
1038 out:
1039         pr_err("failed with %d\n", ret);
1040         return ret;
1041
1042 }
1043
1044 static int snd_compress_remove_device(struct snd_compr *device)
1045 {
1046         return snd_card_free(device->card);
1047 }
1048
1049 /**
1050  * snd_compress_register - register compressed device
1051  *
1052  * @device: compressed device to register
1053  */
1054 int snd_compress_register(struct snd_compr *device)
1055 {
1056         int retval;
1057
1058         if (device->name == NULL || device->ops == NULL)
1059                 return -EINVAL;
1060
1061         pr_debug("Registering compressed device %s\n", device->name);
1062         if (snd_BUG_ON(!device->ops->open))
1063                 return -EINVAL;
1064         if (snd_BUG_ON(!device->ops->free))
1065                 return -EINVAL;
1066         if (snd_BUG_ON(!device->ops->set_params))
1067                 return -EINVAL;
1068         if (snd_BUG_ON(!device->ops->trigger))
1069                 return -EINVAL;
1070
1071         mutex_init(&device->lock);
1072
1073         /* register a compressed card */
1074         mutex_lock(&device_mutex);
1075         retval = snd_compress_add_device(device);
1076         mutex_unlock(&device_mutex);
1077         return retval;
1078 }
1079 EXPORT_SYMBOL_GPL(snd_compress_register);
1080
1081 int snd_compress_deregister(struct snd_compr *device)
1082 {
1083         pr_debug("Removing compressed device %s\n", device->name);
1084         mutex_lock(&device_mutex);
1085         snd_compress_remove_device(device);
1086         mutex_unlock(&device_mutex);
1087         return 0;
1088 }
1089 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1090
1091 static int __init snd_compress_init(void)
1092 {
1093         return 0;
1094 }
1095
1096 static void __exit snd_compress_exit(void)
1097 {
1098 }
1099
1100 module_init(snd_compress_init);
1101 module_exit(snd_compress_exit);
1102
1103 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1104 MODULE_AUTHOR("Vinod Koul <[email protected]>");
1105 MODULE_LICENSE("GPL v2");