sound/core/compress_offload.c

   1 /*
   2  *  compress_core.c - compress offload core
   3  *
   4  *  Copyright (C) 2011 Intel Corporation
   5  *  Authors:    Vinod Koul <vinod.koul@linux.intel.com>
   6  *              Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
   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/mm.h>
  32 #include <linux/mutex.h>
  33 #include <linux/poll.h>
  34 #include <linux/slab.h>
  35 #include <linux/sched.h>
  36 #include <linux/uio.h>
  37 #include <linux/uaccess.h>
  38 #include <linux/module.h>
  39 #include <sound/core.h>
  40 #include <sound/initval.h>
  41 #include <sound/compress_params.h>
  42 #include <sound/compress_offload.h>
  43 #include <sound/compress_driver.h>
  44
  45 /* TODO:
  46  * - add substream support for multiple devices in case of
  47  *      SND_DYNAMIC_MINORS is not used
  48  * - Multiple node representation
  49  *      driver should be able to register multiple nodes
  50  */
  51
  52 static DEFINE_MUTEX(device_mutex);
  53
  54 struct snd_compr_file {
  55         unsigned long caps;
  56         struct snd_compr_stream stream;
  57 };
  58
  59 /*
  60  * a note on stream states used:
  61  * we use follwing states in the compressed core
  62  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
  63  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
  64  *      calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
  65  *      state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
  66  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
  67  *      decoding/encoding and rendering/capturing data.
  68  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
  69  *      by calling SNDRV_COMPRESS_DRAIN.
  70  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
  71  *      SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
  72  *      SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
  73  */
  74 static int snd_compr_open(struct inode *inode, struct file *f)
  75 {
  76         struct snd_compr *compr;
  77         struct snd_compr_file *data;
  78         struct snd_compr_runtime *runtime;
  79         enum snd_compr_direction dirn;
  80         int maj = imajor(inode);
  81         int ret;
  82
  83         if ((f->f_flags & O_ACCMODE) == O_WRONLY)
  84                 dirn = SND_COMPRESS_PLAYBACK;
  85         else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
  86                 dirn = SND_COMPRESS_CAPTURE;
  87         else
  88                 return -EINVAL;
  89
  90         if (maj == snd_major)
  91                 compr = snd_lookup_minor_data(iminor(inode),
  92                                         SNDRV_DEVICE_TYPE_COMPRESS);
  93         else
  94                 return -EBADFD;
  95
  96         if (compr == NULL) {
  97                 pr_err("no device data!!!\n");
  98                 return -ENODEV;
  99         }
 100
 101         if (dirn != compr->direction) {
 102                 pr_err("this device doesn't support this direction\n");
 103                 snd_card_unref(compr->card);
 104                 return -EINVAL;
 105         }
 106
 107         data = kzalloc(sizeof(*data), GFP_KERNEL);
 108         if (!data) {
 109                 snd_card_unref(compr->card);
 110                 return -ENOMEM;
 111         }
 112         data->stream.ops = compr->ops;
 113         data->stream.direction = dirn;
 114         data->stream.private_data = compr->private_data;
 115         data->stream.device = compr;
 116         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 117         if (!runtime) {
 118                 kfree(data);
 119                 snd_card_unref(compr->card);
 120                 return -ENOMEM;
 121         }
 122         runtime->state = SNDRV_PCM_STATE_OPEN;
 123         init_waitqueue_head(&runtime->sleep);
 124         data->stream.runtime = runtime;
 125         f->private_data = (void *)data;
 126         mutex_lock(&compr->lock);
 127         ret = compr->ops->open(&data->stream);
 128         mutex_unlock(&compr->lock);
 129         if (ret) {
 130                 kfree(runtime);
 131                 kfree(data);
 132         }
 133         snd_card_unref(compr->card);
 134         return 0;
 135 }
 136
 137 static int snd_compr_free(struct inode *inode, struct file *f)
 138 {
 139         struct snd_compr_file *data = f->private_data;
 140         data->stream.ops->free(&data->stream);
 141         kfree(data->stream.runtime->buffer);
 142         kfree(data->stream.runtime);
 143         kfree(data);
 144         return 0;
 145 }
 146
 147 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 148                 struct snd_compr_tstamp *tstamp)
 149 {
 150         if (!stream->ops->pointer)
 151                 return -ENOTSUPP;
 152         stream->ops->pointer(stream, tstamp);
 153         pr_debug("dsp consumed till %d total %d bytes\n",
 154                 tstamp->byte_offset, tstamp->copied_total);
 155         if (stream->direction == SND_COMPRESS_PLAYBACK)
 156                 stream->runtime->total_bytes_transferred = tstamp->copied_total;
 157         else
 158                 stream->runtime->total_bytes_available = tstamp->copied_total;
 159         return 0;
 160 }
 161
 162 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
 163                 struct snd_compr_avail *avail)
 164 {
 165         memset(avail, 0, sizeof(*avail));
 166         snd_compr_update_tstamp(stream, &avail->tstamp);
 167         /* Still need to return avail even if tstamp can't be filled in */
 168
 169         if (stream->runtime->total_bytes_available == 0 &&
 170                         stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
 171                         stream->direction == SND_COMPRESS_PLAYBACK) {
 172                 pr_debug("detected init and someone forgot to do a write\n");
 173                 return stream->runtime->buffer_size;
 174         }
 175         pr_debug("app wrote %lld, DSP consumed %lld\n",
 176                         stream->runtime->total_bytes_available,
 177                         stream->runtime->total_bytes_transferred);
 178         if (stream->runtime->total_bytes_available ==
 179                                 stream->runtime->total_bytes_transferred) {
 180                 if (stream->direction == SND_COMPRESS_PLAYBACK) {
 181                         pr_debug("both pointers are same, returning full avail\n");
 182                         return stream->runtime->buffer_size;
 183                 } else {
 184                         pr_debug("both pointers are same, returning no avail\n");
 185                         return 0;
 186                 }
 187         }
 188
 189         avail->avail = stream->runtime->total_bytes_available -
 190                         stream->runtime->total_bytes_transferred;
 191         if (stream->direction == SND_COMPRESS_PLAYBACK)
 192                 avail->avail = stream->runtime->buffer_size - avail->avail;
 193
 194         pr_debug("ret avail as %lld\n", avail->avail);
 195         return avail->avail;
 196 }
 197
 198 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 199 {
 200         struct snd_compr_avail avail;
 201
 202         return snd_compr_calc_avail(stream, &avail);
 203 }
 204
 205 static int
 206 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
 207 {
 208         struct snd_compr_avail ioctl_avail;
 209         size_t avail;
 210
 211         avail = snd_compr_calc_avail(stream, &ioctl_avail);
 212         ioctl_avail.avail = avail;
 213
 214         if (copy_to_user((__u64 __user *)arg,
 215                                 &ioctl_avail, sizeof(ioctl_avail)))
 216                 return -EFAULT;
 217         return 0;
 218 }
 219
 220 static int snd_compr_write_data(struct snd_compr_stream *stream,
 221                const char __user *buf, size_t count)
 222 {
 223         void *dstn;
 224         size_t copy;
 225         struct snd_compr_runtime *runtime = stream->runtime;
 226
 227         dstn = runtime->buffer + runtime->app_pointer;
 228         pr_debug("copying %ld at %lld\n",
 229                         (unsigned long)count, runtime->app_pointer);
 230         if (count < runtime->buffer_size - runtime->app_pointer) {
 231                 if (copy_from_user(dstn, buf, count))
 232                         return -EFAULT;
 233                 runtime->app_pointer += count;
 234         } else {
 235                 copy = runtime->buffer_size - runtime->app_pointer;
 236                 if (copy_from_user(dstn, buf, copy))
 237                         return -EFAULT;
 238                 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
 239                         return -EFAULT;
 240                 runtime->app_pointer = count - copy;
 241         }
 242         /* if DSP cares, let it know data has been written */
 243         if (stream->ops->ack)
 244                 stream->ops->ack(stream, count);
 245         return count;
 246 }
 247
 248 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
 249                 size_t count, loff_t *offset)
 250 {
 251         struct snd_compr_file *data = f->private_data;
 252         struct snd_compr_stream *stream;
 253         size_t avail;
 254         int retval;
 255
 256         if (snd_BUG_ON(!data))
 257                 return -EFAULT;
 258
 259         stream = &data->stream;
 260         mutex_lock(&stream->device->lock);
 261         /* write is allowed when stream is running or has been steup */
 262         if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 263                         stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 264                 mutex_unlock(&stream->device->lock);
 265                 return -EBADFD;
 266         }
 267
 268         avail = snd_compr_get_avail(stream);
 269         pr_debug("avail returned %ld\n", (unsigned long)avail);
 270         /* calculate how much we can write to buffer */
 271         if (avail > count)
 272                 avail = count;
 273
 274         if (stream->ops->copy) {
 275                 char __user* cbuf = (char __user*)buf;
 276                 retval = stream->ops->copy(stream, cbuf, avail);
 277         } else {
 278                 retval = snd_compr_write_data(stream, buf, avail);
 279         }
 280         if (retval > 0)
 281                 stream->runtime->total_bytes_available += retval;
 282
 283         /* while initiating the stream, write should be called before START
 284          * call, so in setup move state */
 285         if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
 286                 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 287                 pr_debug("stream prepared, Houston we are good to go\n");
 288         }
 289
 290         mutex_unlock(&stream->device->lock);
 291         return retval;
 292 }
 293
 294
 295 static ssize_t snd_compr_read(struct file *f, char __user *buf,
 296                 size_t count, loff_t *offset)
 297 {
 298         struct snd_compr_file *data = f->private_data;
 299         struct snd_compr_stream *stream;
 300         size_t avail;
 301         int retval;
 302
 303         if (snd_BUG_ON(!data))
 304                 return -EFAULT;
 305
 306         stream = &data->stream;
 307         mutex_lock(&stream->device->lock);
 308
 309         /* read is allowed when stream is running */
 310         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 311                 retval = -EBADFD;
 312                 goto out;
 313         }
 314
 315         avail = snd_compr_get_avail(stream);
 316         pr_debug("avail returned %ld\n", (unsigned long)avail);
 317         /* calculate how much we can read from buffer */
 318         if (avail > count)
 319                 avail = count;
 320
 321         if (stream->ops->copy) {
 322                 retval = stream->ops->copy(stream, buf, avail);
 323         } else {
 324                 retval = -ENXIO;
 325                 goto out;
 326         }
 327         if (retval > 0)
 328                 stream->runtime->total_bytes_transferred += retval;
 329
 330 out:
 331         mutex_unlock(&stream->device->lock);
 332         return retval;
 333 }
 334
 335 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
 336 {
 337         return -ENXIO;
 338 }
 339
 340 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
 341 {
 342         if (stream->direction == SND_COMPRESS_PLAYBACK)
 343                 return POLLOUT | POLLWRNORM;
 344         else
 345                 return POLLIN | POLLRDNORM;
 346 }
 347
 348 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
 349 {
 350         struct snd_compr_file *data = f->private_data;
 351         struct snd_compr_stream *stream;
 352         size_t avail;
 353         int retval = 0;
 354
 355         if (snd_BUG_ON(!data))
 356                 return -EFAULT;
 357         stream = &data->stream;
 358         if (snd_BUG_ON(!stream))
 359                 return -EFAULT;
 360
 361         mutex_lock(&stream->device->lock);
 362         if (stream->runtime->state == SNDRV_PCM_STATE_PAUSED ||
 363                         stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 364                 retval = -EBADFD;
 365                 goto out;
 366         }
 367         poll_wait(f, &stream->runtime->sleep, wait);
 368
 369         avail = snd_compr_get_avail(stream);
 370         pr_debug("avail is %ld\n", (unsigned long)avail);
 371         /* check if we have at least one fragment to fill */
 372         switch (stream->runtime->state) {
 373         case SNDRV_PCM_STATE_DRAINING:
 374                 /* stream has been woken up after drain is complete
 375                  * draining done so set stream state to stopped
 376                  */
 377                 retval = snd_compr_get_poll(stream);
 378                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 379                 break;
 380         case SNDRV_PCM_STATE_RUNNING:
 381         case SNDRV_PCM_STATE_PREPARED:
 382         case SNDRV_PCM_STATE_PAUSED:
 383                 if (avail >= stream->runtime->fragment_size)
 384                         retval = snd_compr_get_poll(stream);
 385                 break;
 386         default:
 387                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 388                         retval = POLLOUT | POLLWRNORM | POLLERR;
 389                 else
 390                         retval = POLLIN | POLLRDNORM | POLLERR;
 391                 break;
 392         }
 393 out:
 394         mutex_unlock(&stream->device->lock);
 395         return retval;
 396 }
 397
 398 static int
 399 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 400 {
 401         int retval;
 402         struct snd_compr_caps caps;
 403
 404         if (!stream->ops->get_caps)
 405                 return -ENXIO;
 406
 407         retval = stream->ops->get_caps(stream, &caps);
 408         if (retval)
 409                 goto out;
 410         if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 411                 retval = -EFAULT;
 412 out:
 413         return retval;
 414 }
 415
 416 static int
 417 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 418 {
 419         int retval;
 420         struct snd_compr_codec_caps *caps;
 421
 422         if (!stream->ops->get_codec_caps)
 423                 return -ENXIO;
 424
 425         caps = kmalloc(sizeof(*caps), GFP_KERNEL);
 426         if (!caps)
 427                 return -ENOMEM;
 428
 429         retval = stream->ops->get_codec_caps(stream, caps);
 430         if (retval)
 431                 goto out;
 432         if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 433                 retval = -EFAULT;
 434
 435 out:
 436         kfree(caps);
 437         return retval;
 438 }
 439
 440 /* revisit this with snd_pcm_preallocate_xxx */
 441 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 442                 struct snd_compr_params *params)
 443 {
 444         unsigned int buffer_size;
 445         void *buffer;
 446
 447         buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 448         if (stream->ops->copy) {
 449                 buffer = NULL;
 450                 /* if copy is defined the driver will be required to copy
 451                  * the data from core
 452                  */
 453         } else {
 454                 buffer = kmalloc(buffer_size, GFP_KERNEL);
 455                 if (!buffer)
 456                         return -ENOMEM;
 457         }
 458         stream->runtime->fragment_size = params->buffer.fragment_size;
 459         stream->runtime->fragments = params->buffer.fragments;
 460         stream->runtime->buffer = buffer;
 461         stream->runtime->buffer_size = buffer_size;
 462         return 0;
 463 }
 464
 465 static int snd_compress_check_input(struct snd_compr_params *params)
 466 {
 467         /* first let's check the buffer parameter's */
 468         if (params->buffer.fragment_size == 0 ||
 469                         params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
 470                 return -EINVAL;
 471
 472         /* now codec parameters */
 473         if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 474                 return -EINVAL;
 475
 476         if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 477                 return -EINVAL;
 478
 479         if (!(params->codec.sample_rate & SNDRV_PCM_RATE_8000_192000))
 480                 return -EINVAL;
 481
 482         return 0;
 483 }
 484
 485 static int
 486 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 487 {
 488         struct snd_compr_params *params;
 489         int retval;
 490
 491         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 492                 /*
 493                  * we should allow parameter change only when stream has been
 494                  * opened not in other cases
 495                  */
 496                 params = kmalloc(sizeof(*params), GFP_KERNEL);
 497                 if (!params)
 498                         return -ENOMEM;
 499                 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 500                         retval = -EFAULT;
 501                         goto out;
 502                 }
 503
 504                 retval = snd_compress_check_input(params);
 505                 if (retval)
 506                         goto out;
 507
 508                 retval = snd_compr_allocate_buffer(stream, params);
 509                 if (retval) {
 510                         retval = -ENOMEM;
 511                         goto out;
 512                 }
 513
 514                 retval = stream->ops->set_params(stream, params);
 515                 if (retval)
 516                         goto out;
 517
 518                 stream->metadata_set = false;
 519                 stream->next_track = false;
 520
 521                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 522                         stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 523                 else
 524                         stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 525         } else {
 526                 return -EPERM;
 527         }
 528 out:
 529         kfree(params);
 530         return retval;
 531 }
 532
 533 static int
 534 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 535 {
 536         struct snd_codec *params;
 537         int retval;
 538
 539         if (!stream->ops->get_params)
 540                 return -EBADFD;
 541
 542         params = kmalloc(sizeof(*params), GFP_KERNEL);
 543         if (!params)
 544                 return -ENOMEM;
 545         retval = stream->ops->get_params(stream, params);
 546         if (retval)
 547                 goto out;
 548         if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 549                 retval = -EFAULT;
 550
 551 out:
 552         kfree(params);
 553         return retval;
 554 }
 555
 556 static int
 557 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 558 {
 559         struct snd_compr_metadata metadata;
 560         int retval;
 561
 562         if (!stream->ops->get_metadata)
 563                 return -ENXIO;
 564
 565         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 566                 return -EFAULT;
 567
 568         retval = stream->ops->get_metadata(stream, &metadata);
 569         if (retval != 0)
 570                 return retval;
 571
 572         if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 573                 return -EFAULT;
 574
 575         return 0;
 576 }
 577
 578 static int
 579 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 580 {
 581         struct snd_compr_metadata metadata;
 582         int retval;
 583
 584         if (!stream->ops->set_metadata)
 585                 return -ENXIO;
 586         /*
 587         * we should allow parameter change only when stream has been
 588         * opened not in other cases
 589         */
 590         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 591                 return -EFAULT;
 592
 593         retval = stream->ops->set_metadata(stream, &metadata);
 594         stream->metadata_set = true;
 595
 596         return retval;
 597 }
 598
 599 static inline int
 600 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 601 {
 602         struct snd_compr_tstamp tstamp = {0};
 603         int ret;
 604
 605         ret = snd_compr_update_tstamp(stream, &tstamp);
 606         if (ret == 0)
 607                 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 608                         &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 609         return ret;
 610 }
 611
 612 static int snd_compr_pause(struct snd_compr_stream *stream)
 613 {
 614         int retval;
 615
 616         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 617                 return -EPERM;
 618         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 619         if (!retval)
 620                 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 621         return retval;
 622 }
 623
 624 static int snd_compr_resume(struct snd_compr_stream *stream)
 625 {
 626         int retval;
 627
 628         if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 629                 return -EPERM;
 630         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 631         if (!retval)
 632                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 633         return retval;
 634 }
 635
 636 static int snd_compr_start(struct snd_compr_stream *stream)
 637 {
 638         int retval;
 639
 640         if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
 641                 return -EPERM;
 642         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 643         if (!retval)
 644                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 645         return retval;
 646 }
 647
 648 static int snd_compr_stop(struct snd_compr_stream *stream)
 649 {
 650         int retval;
 651
 652         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 653                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 654                 return -EPERM;
 655         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 656         if (!retval) {
 657                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 658                 wake_up(&stream->runtime->sleep);
 659                 stream->runtime->app_pointer = 0;
 660                 stream->runtime->total_bytes_available = 0;
 661                 stream->runtime->total_bytes_transferred = 0;
 662         }
 663         return retval;
 664 }
 665
 666 static int snd_compr_drain(struct snd_compr_stream *stream)
 667 {
 668         int retval;
 669
 670         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 671                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 672                 return -EPERM;
 673         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 674         if (!retval) {
 675                 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 676                 wake_up(&stream->runtime->sleep);
 677         }
 678         return retval;
 679 }
 680
 681 static int snd_compr_next_track(struct snd_compr_stream *stream)
 682 {
 683         int retval;
 684
 685         /* only a running stream can transition to next track */
 686         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 687                 return -EPERM;
 688
 689         /* you can signal next track isf this is intended to be a gapless stream
 690          * and current track metadata is set
 691          */
 692         if (stream->metadata_set == false)
 693                 return -EPERM;
 694
 695         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 696         if (retval != 0)
 697                 return retval;
 698         stream->metadata_set = false;
 699         stream->next_track = true;
 700         return 0;
 701 }
 702
 703 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 704 {
 705         int retval;
 706         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 707                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 708                 return -EPERM;
 709         /* stream can be drained only when next track has been signalled */
 710         if (stream->next_track == false)
 711                 return -EPERM;
 712
 713         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 714
 715         stream->next_track = false;
 716         return retval;
 717 }
 718
 719 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 720 {
 721         struct snd_compr_file *data = f->private_data;
 722         struct snd_compr_stream *stream;
 723         int retval = -ENOTTY;
 724
 725         if (snd_BUG_ON(!data))
 726                 return -EFAULT;
 727         stream = &data->stream;
 728         if (snd_BUG_ON(!stream))
 729                 return -EFAULT;
 730         mutex_lock(&stream->device->lock);
 731         switch (_IOC_NR(cmd)) {
 732         case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 733                 put_user(SNDRV_COMPRESS_VERSION,
 734                                 (int __user *)arg) ? -EFAULT : 0;
 735                 break;
 736         case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 737                 retval = snd_compr_get_caps(stream, arg);
 738                 break;
 739         case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 740                 retval = snd_compr_get_codec_caps(stream, arg);
 741                 break;
 742         case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 743                 retval = snd_compr_set_params(stream, arg);
 744                 break;
 745         case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 746                 retval = snd_compr_get_params(stream, arg);
 747                 break;
 748         case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 749                 retval = snd_compr_set_metadata(stream, arg);
 750                 break;
 751         case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 752                 retval = snd_compr_get_metadata(stream, arg);
 753                 break;
 754         case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 755                 retval = snd_compr_tstamp(stream, arg);
 756                 break;
 757         case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 758                 retval = snd_compr_ioctl_avail(stream, arg);
 759                 break;
 760         case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 761                 retval = snd_compr_pause(stream);
 762                 break;
 763         case _IOC_NR(SNDRV_COMPRESS_RESUME):
 764                 retval = snd_compr_resume(stream);
 765                 break;
 766         case _IOC_NR(SNDRV_COMPRESS_START):
 767                 retval = snd_compr_start(stream);
 768                 break;
 769         case _IOC_NR(SNDRV_COMPRESS_STOP):
 770                 retval = snd_compr_stop(stream);
 771                 break;
 772         case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 773                 retval = snd_compr_drain(stream);
 774                 break;
 775         case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 776                 retval = snd_compr_partial_drain(stream);
 777                 break;
 778         case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 779                 retval = snd_compr_next_track(stream);
 780                 break;
 781
 782         }
 783         mutex_unlock(&stream->device->lock);
 784         return retval;
 785 }
 786
 787 static const struct file_operations snd_compr_file_ops = {
 788                 .owner =        THIS_MODULE,
 789                 .open =         snd_compr_open,
 790                 .release =      snd_compr_free,
 791                 .write =        snd_compr_write,
 792                 .read =         snd_compr_read,
 793                 .unlocked_ioctl = snd_compr_ioctl,
 794                 .mmap =         snd_compr_mmap,
 795                 .poll =         snd_compr_poll,
 796 };
 797
 798 static int snd_compress_dev_register(struct snd_device *device)
 799 {
 800         int ret = -EINVAL;
 801         char str[16];
 802         struct snd_compr *compr;
 803
 804         if (snd_BUG_ON(!device || !device->device_data))
 805                 return -EBADFD;
 806         compr = device->device_data;
 807
 808         sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
 809         pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
 810                         compr->direction);
 811         /* register compressed device */
 812         ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
 813                         compr->device, &snd_compr_file_ops, compr, str);
 814         if (ret < 0) {
 815                 pr_err("snd_register_device failed\n %d", ret);
 816                 return ret;
 817         }
 818         return ret;
 819
 820 }
 821
 822 static int snd_compress_dev_disconnect(struct snd_device *device)
 823 {
 824         struct snd_compr *compr;
 825
 826         compr = device->device_data;
 827         snd_unregister_device(compr->direction, compr->card, compr->device);
 828         return 0;
 829 }
 830
 831 /*
 832  * snd_compress_new: create new compress device
 833  * @card: sound card pointer
 834  * @device: device number
 835  * @dirn: device direction, should be of type enum snd_compr_direction
 836  * @compr: compress device pointer
 837  */
 838 int snd_compress_new(struct snd_card *card, int device,
 839                         int dirn, struct snd_compr *compr)
 840 {
 841         static struct snd_device_ops ops = {
 842                 .dev_free = NULL,
 843                 .dev_register = snd_compress_dev_register,
 844                 .dev_disconnect = snd_compress_dev_disconnect,
 845         };
 846
 847         compr->card = card;
 848         compr->device = device;
 849         compr->direction = dirn;
 850         return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
 851 }
 852 EXPORT_SYMBOL_GPL(snd_compress_new);
 853
 854 static int snd_compress_add_device(struct snd_compr *device)
 855 {
 856         int ret;
 857
 858         if (!device->card)
 859                 return -EINVAL;
 860
 861         /* register the card */
 862         ret = snd_card_register(device->card);
 863         if (ret)
 864                 goto out;
 865         return 0;
 866
 867 out:
 868         pr_err("failed with %d\n", ret);
 869         return ret;
 870
 871 }
 872
 873 static int snd_compress_remove_device(struct snd_compr *device)
 874 {
 875         return snd_card_free(device->card);
 876 }
 877
 878 /**
 879  * snd_compress_register - register compressed device
 880  *
 881  * @device: compressed device to register
 882  */
 883 int snd_compress_register(struct snd_compr *device)
 884 {
 885         int retval;
 886
 887         if (device->name == NULL || device->dev == NULL || device->ops == NULL)
 888                 return -EINVAL;
 889
 890         pr_debug("Registering compressed device %s\n", device->name);
 891         if (snd_BUG_ON(!device->ops->open))
 892                 return -EINVAL;
 893         if (snd_BUG_ON(!device->ops->free))
 894                 return -EINVAL;
 895         if (snd_BUG_ON(!device->ops->set_params))
 896                 return -EINVAL;
 897         if (snd_BUG_ON(!device->ops->trigger))
 898                 return -EINVAL;
 899
 900         mutex_init(&device->lock);
 901
 902         /* register a compressed card */
 903         mutex_lock(&device_mutex);
 904         retval = snd_compress_add_device(device);
 905         mutex_unlock(&device_mutex);
 906         return retval;
 907 }
 908 EXPORT_SYMBOL_GPL(snd_compress_register);
 909
 910 int snd_compress_deregister(struct snd_compr *device)
 911 {
 912         pr_debug("Removing compressed device %s\n", device->name);
 913         mutex_lock(&device_mutex);
 914         snd_compress_remove_device(device);
 915         mutex_unlock(&device_mutex);
 916         return 0;
 917 }
 918 EXPORT_SYMBOL_GPL(snd_compress_deregister);
 919
 920 static int __init snd_compress_init(void)
 921 {
 922         return 0;
 923 }
 924
 925 static void __exit snd_compress_exit(void)
 926 {
 927 }
 928
 929 module_init(snd_compress_init);
 930 module_exit(snd_compress_exit);
 931
 932 MODULE_DESCRIPTION("ALSA Compressed offload framework");
 933 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
 934 MODULE_LICENSE("GPL v2");