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/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 <sound/core.h>
  42 #include <sound/initval.h>
  43 #include <sound/compress_params.h>
  44 #include <sound/compress_offload.h>
  45 #include <sound/compress_driver.h>
  46
  47 /* TODO:
  48  * - add substream support for multiple devices in case of
  49  *      SND_DYNAMIC_MINORS is not used
  50  * - Multiple node representation
  51  *      driver should be able to register multiple nodes
  52  */
  53
  54 static DEFINE_MUTEX(device_mutex);
  55
  56 struct snd_compr_file {
  57         unsigned long caps;
  58         struct snd_compr_stream stream;
  59 };
  60
  61 /*
  62  * a note on stream states used:
  63  * we use follwing states in the compressed core
  64  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
  65  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
  66  *      calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
  67  *      state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
  68  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
  69  *      decoding/encoding and rendering/capturing data.
  70  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
  71  *      by calling SNDRV_COMPRESS_DRAIN.
  72  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
  73  *      SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
  74  *      SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
  75  */
  76 static int snd_compr_open(struct inode *inode, struct file *f)
  77 {
  78         struct snd_compr *compr;
  79         struct snd_compr_file *data;
  80         struct snd_compr_runtime *runtime;
  81         enum snd_compr_direction dirn;
  82         int maj = imajor(inode);
  83         int ret;
  84
  85         if ((f->f_flags & O_ACCMODE) == O_WRONLY)
  86                 dirn = SND_COMPRESS_PLAYBACK;
  87         else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
  88                 dirn = SND_COMPRESS_CAPTURE;
  89         else
  90                 return -EINVAL;
  91
  92         if (maj == snd_major)
  93                 compr = snd_lookup_minor_data(iminor(inode),
  94                                         SNDRV_DEVICE_TYPE_COMPRESS);
  95         else
  96                 return -EBADFD;
  97
  98         if (compr == NULL) {
  99                 pr_err("no device data!!!\n");
 100                 return -ENODEV;
 101         }
 102
 103         if (dirn != compr->direction) {
 104                 pr_err("this device doesn't support this direction\n");
 105                 snd_card_unref(compr->card);
 106                 return -EINVAL;
 107         }
 108
 109         data = kzalloc(sizeof(*data), GFP_KERNEL);
 110         if (!data) {
 111                 snd_card_unref(compr->card);
 112                 return -ENOMEM;
 113         }
 114         data->stream.ops = compr->ops;
 115         data->stream.direction = dirn;
 116         data->stream.private_data = compr->private_data;
 117         data->stream.device = compr;
 118         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 119         if (!runtime) {
 120                 kfree(data);
 121                 snd_card_unref(compr->card);
 122                 return -ENOMEM;
 123         }
 124         runtime->state = SNDRV_PCM_STATE_OPEN;
 125         init_waitqueue_head(&runtime->sleep);
 126         data->stream.runtime = runtime;
 127         f->private_data = (void *)data;
 128         mutex_lock(&compr->lock);
 129         ret = compr->ops->open(&data->stream);
 130         mutex_unlock(&compr->lock);
 131         if (ret) {
 132                 kfree(runtime);
 133                 kfree(data);
 134         }
 135         snd_card_unref(compr->card);
 136         return 0;
 137 }
 138
 139 static int snd_compr_free(struct inode *inode, struct file *f)
 140 {
 141         struct snd_compr_file *data = f->private_data;
 142         struct snd_compr_runtime *runtime = data->stream.runtime;
 143
 144         switch (runtime->state) {
 145         case SNDRV_PCM_STATE_RUNNING:
 146         case SNDRV_PCM_STATE_DRAINING:
 147         case SNDRV_PCM_STATE_PAUSED:
 148                 data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
 149                 break;
 150         default:
 151                 break;
 152         }
 153
 154         data->stream.ops->free(&data->stream);
 155         kfree(data->stream.runtime->buffer);
 156         kfree(data->stream.runtime);
 157         kfree(data);
 158         return 0;
 159 }
 160
 161 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 162                 struct snd_compr_tstamp *tstamp)
 163 {
 164         if (!stream->ops->pointer)
 165                 return -ENOTSUPP;
 166         stream->ops->pointer(stream, tstamp);
 167         pr_debug("dsp consumed till %d total %d bytes\n",
 168                 tstamp->byte_offset, tstamp->copied_total);
 169         if (stream->direction == SND_COMPRESS_PLAYBACK)
 170                 stream->runtime->total_bytes_transferred = tstamp->copied_total;
 171         else
 172                 stream->runtime->total_bytes_available = tstamp->copied_total;
 173         return 0;
 174 }
 175
 176 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
 177                 struct snd_compr_avail *avail)
 178 {
 179         memset(avail, 0, sizeof(*avail));
 180         snd_compr_update_tstamp(stream, &avail->tstamp);
 181         /* Still need to return avail even if tstamp can't be filled in */
 182
 183         if (stream->runtime->total_bytes_available == 0 &&
 184                         stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
 185                         stream->direction == SND_COMPRESS_PLAYBACK) {
 186                 pr_debug("detected init and someone forgot to do a write\n");
 187                 return stream->runtime->buffer_size;
 188         }
 189         pr_debug("app wrote %lld, DSP consumed %lld\n",
 190                         stream->runtime->total_bytes_available,
 191                         stream->runtime->total_bytes_transferred);
 192         if (stream->runtime->total_bytes_available ==
 193                                 stream->runtime->total_bytes_transferred) {
 194                 if (stream->direction == SND_COMPRESS_PLAYBACK) {
 195                         pr_debug("both pointers are same, returning full avail\n");
 196                         return stream->runtime->buffer_size;
 197                 } else {
 198                         pr_debug("both pointers are same, returning no avail\n");
 199                         return 0;
 200                 }
 201         }
 202
 203         avail->avail = stream->runtime->total_bytes_available -
 204                         stream->runtime->total_bytes_transferred;
 205         if (stream->direction == SND_COMPRESS_PLAYBACK)
 206                 avail->avail = stream->runtime->buffer_size - avail->avail;
 207
 208         pr_debug("ret avail as %lld\n", avail->avail);
 209         return avail->avail;
 210 }
 211
 212 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 213 {
 214         struct snd_compr_avail avail;
 215
 216         return snd_compr_calc_avail(stream, &avail);
 217 }
 218
 219 static int
 220 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
 221 {
 222         struct snd_compr_avail ioctl_avail;
 223         size_t avail;
 224
 225         avail = snd_compr_calc_avail(stream, &ioctl_avail);
 226         ioctl_avail.avail = avail;
 227
 228         if (copy_to_user((__u64 __user *)arg,
 229                                 &ioctl_avail, sizeof(ioctl_avail)))
 230                 return -EFAULT;
 231         return 0;
 232 }
 233
 234 static int snd_compr_write_data(struct snd_compr_stream *stream,
 235                const char __user *buf, size_t count)
 236 {
 237         void *dstn;
 238         size_t copy;
 239         struct snd_compr_runtime *runtime = stream->runtime;
 240         /* 64-bit Modulus */
 241         u64 app_pointer = div64_u64(runtime->total_bytes_available,
 242                                     runtime->buffer_size);
 243         app_pointer = runtime->total_bytes_available -
 244                       (app_pointer * runtime->buffer_size);
 245
 246         dstn = runtime->buffer + app_pointer;
 247         pr_debug("copying %ld at %lld\n",
 248                         (unsigned long)count, app_pointer);
 249         if (count < runtime->buffer_size - app_pointer) {
 250                 if (copy_from_user(dstn, buf, count))
 251                         return -EFAULT;
 252         } else {
 253                 copy = runtime->buffer_size - app_pointer;
 254                 if (copy_from_user(dstn, buf, copy))
 255                         return -EFAULT;
 256                 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
 257                         return -EFAULT;
 258         }
 259         /* if DSP cares, let it know data has been written */
 260         if (stream->ops->ack)
 261                 stream->ops->ack(stream, count);
 262         return count;
 263 }
 264
 265 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
 266                 size_t count, loff_t *offset)
 267 {
 268         struct snd_compr_file *data = f->private_data;
 269         struct snd_compr_stream *stream;
 270         size_t avail;
 271         int retval;
 272
 273         if (snd_BUG_ON(!data))
 274                 return -EFAULT;
 275
 276         stream = &data->stream;
 277         mutex_lock(&stream->device->lock);
 278         /* write is allowed when stream is running or has been steup */
 279         if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 280                         stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 281                 mutex_unlock(&stream->device->lock);
 282                 return -EBADFD;
 283         }
 284
 285         avail = snd_compr_get_avail(stream);
 286         pr_debug("avail returned %ld\n", (unsigned long)avail);
 287         /* calculate how much we can write to buffer */
 288         if (avail > count)
 289                 avail = count;
 290
 291         if (stream->ops->copy) {
 292                 char __user* cbuf = (char __user*)buf;
 293                 retval = stream->ops->copy(stream, cbuf, avail);
 294         } else {
 295                 retval = snd_compr_write_data(stream, buf, avail);
 296         }
 297         if (retval > 0)
 298                 stream->runtime->total_bytes_available += retval;
 299
 300         /* while initiating the stream, write should be called before START
 301          * call, so in setup move state */
 302         if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
 303                 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 304                 pr_debug("stream prepared, Houston we are good to go\n");
 305         }
 306
 307         mutex_unlock(&stream->device->lock);
 308         return retval;
 309 }
 310
 311
 312 static ssize_t snd_compr_read(struct file *f, char __user *buf,
 313                 size_t count, loff_t *offset)
 314 {
 315         struct snd_compr_file *data = f->private_data;
 316         struct snd_compr_stream *stream;
 317         size_t avail;
 318         int retval;
 319
 320         if (snd_BUG_ON(!data))
 321                 return -EFAULT;
 322
 323         stream = &data->stream;
 324         mutex_lock(&stream->device->lock);
 325
 326         /* read is allowed when stream is running, paused, draining and setup
 327          * (yes setup is state which we transition to after stop, so if user
 328          * wants to read data after stop we allow that)
 329          */
 330         switch (stream->runtime->state) {
 331         case SNDRV_PCM_STATE_OPEN:
 332         case SNDRV_PCM_STATE_PREPARED:
 333         case SNDRV_PCM_STATE_XRUN:
 334         case SNDRV_PCM_STATE_SUSPENDED:
 335         case SNDRV_PCM_STATE_DISCONNECTED:
 336                 retval = -EBADFD;
 337                 goto out;
 338         }
 339
 340         avail = snd_compr_get_avail(stream);
 341         pr_debug("avail returned %ld\n", (unsigned long)avail);
 342         /* calculate how much we can read from buffer */
 343         if (avail > count)
 344                 avail = count;
 345
 346         if (stream->ops->copy) {
 347                 retval = stream->ops->copy(stream, buf, avail);
 348         } else {
 349                 retval = -ENXIO;
 350                 goto out;
 351         }
 352         if (retval > 0)
 353                 stream->runtime->total_bytes_transferred += retval;
 354
 355 out:
 356         mutex_unlock(&stream->device->lock);
 357         return retval;
 358 }
 359
 360 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
 361 {
 362         return -ENXIO;
 363 }
 364
 365 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
 366 {
 367         if (stream->direction == SND_COMPRESS_PLAYBACK)
 368                 return POLLOUT | POLLWRNORM;
 369         else
 370                 return POLLIN | POLLRDNORM;
 371 }
 372
 373 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
 374 {
 375         struct snd_compr_file *data = f->private_data;
 376         struct snd_compr_stream *stream;
 377         size_t avail;
 378         int retval = 0;
 379
 380         if (snd_BUG_ON(!data))
 381                 return -EFAULT;
 382         stream = &data->stream;
 383         if (snd_BUG_ON(!stream))
 384                 return -EFAULT;
 385
 386         mutex_lock(&stream->device->lock);
 387         if (stream->runtime->state == SNDRV_PCM_STATE_PAUSED ||
 388                         stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 389                 retval = -EBADFD;
 390                 goto out;
 391         }
 392         poll_wait(f, &stream->runtime->sleep, wait);
 393
 394         avail = snd_compr_get_avail(stream);
 395         pr_debug("avail is %ld\n", (unsigned long)avail);
 396         /* check if we have at least one fragment to fill */
 397         switch (stream->runtime->state) {
 398         case SNDRV_PCM_STATE_DRAINING:
 399                 /* stream has been woken up after drain is complete
 400                  * draining done so set stream state to stopped
 401                  */
 402                 retval = snd_compr_get_poll(stream);
 403                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 404                 break;
 405         case SNDRV_PCM_STATE_RUNNING:
 406         case SNDRV_PCM_STATE_PREPARED:
 407         case SNDRV_PCM_STATE_PAUSED:
 408                 if (avail >= stream->runtime->fragment_size)
 409                         retval = snd_compr_get_poll(stream);
 410                 break;
 411         default:
 412                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 413                         retval = POLLOUT | POLLWRNORM | POLLERR;
 414                 else
 415                         retval = POLLIN | POLLRDNORM | POLLERR;
 416                 break;
 417         }
 418 out:
 419         mutex_unlock(&stream->device->lock);
 420         return retval;
 421 }
 422
 423 static int
 424 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 425 {
 426         int retval;
 427         struct snd_compr_caps caps;
 428
 429         if (!stream->ops->get_caps)
 430                 return -ENXIO;
 431
 432         memset(&caps, 0, sizeof(caps));
 433         retval = stream->ops->get_caps(stream, &caps);
 434         if (retval)
 435                 goto out;
 436         if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 437                 retval = -EFAULT;
 438 out:
 439         return retval;
 440 }
 441
 442 static int
 443 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 444 {
 445         int retval;
 446         struct snd_compr_codec_caps *caps;
 447
 448         if (!stream->ops->get_codec_caps)
 449                 return -ENXIO;
 450
 451         caps = kzalloc(sizeof(*caps), GFP_KERNEL);
 452         if (!caps)
 453                 return -ENOMEM;
 454
 455         retval = stream->ops->get_codec_caps(stream, caps);
 456         if (retval)
 457                 goto out;
 458         if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 459                 retval = -EFAULT;
 460
 461 out:
 462         kfree(caps);
 463         return retval;
 464 }
 465
 466 /* revisit this with snd_pcm_preallocate_xxx */
 467 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 468                 struct snd_compr_params *params)
 469 {
 470         unsigned int buffer_size;
 471         void *buffer;
 472
 473         buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 474         if (stream->ops->copy) {
 475                 buffer = NULL;
 476                 /* if copy is defined the driver will be required to copy
 477                  * the data from core
 478                  */
 479         } else {
 480                 buffer = kmalloc(buffer_size, GFP_KERNEL);
 481                 if (!buffer)
 482                         return -ENOMEM;
 483         }
 484         stream->runtime->fragment_size = params->buffer.fragment_size;
 485         stream->runtime->fragments = params->buffer.fragments;
 486         stream->runtime->buffer = buffer;
 487         stream->runtime->buffer_size = buffer_size;
 488         return 0;
 489 }
 490
 491 static int snd_compress_check_input(struct snd_compr_params *params)
 492 {
 493         /* first let's check the buffer parameter's */
 494         if (params->buffer.fragment_size == 0 ||
 495                         params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
 496                 return -EINVAL;
 497
 498         /* now codec parameters */
 499         if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 500                 return -EINVAL;
 501
 502         if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 503                 return -EINVAL;
 504
 505         if (!(params->codec.sample_rate & SNDRV_PCM_RATE_8000_192000))
 506                 return -EINVAL;
 507
 508         return 0;
 509 }
 510
 511 static int
 512 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 513 {
 514         struct snd_compr_params *params;
 515         int retval;
 516
 517         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 518                 /*
 519                  * we should allow parameter change only when stream has been
 520                  * opened not in other cases
 521                  */
 522                 params = kmalloc(sizeof(*params), GFP_KERNEL);
 523                 if (!params)
 524                         return -ENOMEM;
 525                 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 526                         retval = -EFAULT;
 527                         goto out;
 528                 }
 529
 530                 retval = snd_compress_check_input(params);
 531                 if (retval)
 532                         goto out;
 533
 534                 retval = snd_compr_allocate_buffer(stream, params);
 535                 if (retval) {
 536                         retval = -ENOMEM;
 537                         goto out;
 538                 }
 539
 540                 retval = stream->ops->set_params(stream, params);
 541                 if (retval)
 542                         goto out;
 543
 544                 stream->metadata_set = false;
 545                 stream->next_track = false;
 546
 547                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 548                         stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 549                 else
 550                         stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 551         } else {
 552                 return -EPERM;
 553         }
 554 out:
 555         kfree(params);
 556         return retval;
 557 }
 558
 559 static int
 560 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 561 {
 562         struct snd_codec *params;
 563         int retval;
 564
 565         if (!stream->ops->get_params)
 566                 return -EBADFD;
 567
 568         params = kzalloc(sizeof(*params), GFP_KERNEL);
 569         if (!params)
 570                 return -ENOMEM;
 571         retval = stream->ops->get_params(stream, params);
 572         if (retval)
 573                 goto out;
 574         if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 575                 retval = -EFAULT;
 576
 577 out:
 578         kfree(params);
 579         return retval;
 580 }
 581
 582 static int
 583 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 584 {
 585         struct snd_compr_metadata metadata;
 586         int retval;
 587
 588         if (!stream->ops->get_metadata)
 589                 return -ENXIO;
 590
 591         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 592                 return -EFAULT;
 593
 594         retval = stream->ops->get_metadata(stream, &metadata);
 595         if (retval != 0)
 596                 return retval;
 597
 598         if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 599                 return -EFAULT;
 600
 601         return 0;
 602 }
 603
 604 static int
 605 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 606 {
 607         struct snd_compr_metadata metadata;
 608         int retval;
 609
 610         if (!stream->ops->set_metadata)
 611                 return -ENXIO;
 612         /*
 613         * we should allow parameter change only when stream has been
 614         * opened not in other cases
 615         */
 616         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 617                 return -EFAULT;
 618
 619         retval = stream->ops->set_metadata(stream, &metadata);
 620         stream->metadata_set = true;
 621
 622         return retval;
 623 }
 624
 625 static inline int
 626 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 627 {
 628         struct snd_compr_tstamp tstamp = {0};
 629         int ret;
 630
 631         ret = snd_compr_update_tstamp(stream, &tstamp);
 632         if (ret == 0)
 633                 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 634                         &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 635         return ret;
 636 }
 637
 638 static int snd_compr_pause(struct snd_compr_stream *stream)
 639 {
 640         int retval;
 641
 642         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 643                 return -EPERM;
 644         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 645         if (!retval)
 646                 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 647         return retval;
 648 }
 649
 650 static int snd_compr_resume(struct snd_compr_stream *stream)
 651 {
 652         int retval;
 653
 654         if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 655                 return -EPERM;
 656         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 657         if (!retval)
 658                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 659         return retval;
 660 }
 661
 662 static int snd_compr_start(struct snd_compr_stream *stream)
 663 {
 664         int retval;
 665
 666         if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
 667                 return -EPERM;
 668         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 669         if (!retval)
 670                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 671         return retval;
 672 }
 673
 674 static int snd_compr_stop(struct snd_compr_stream *stream)
 675 {
 676         int retval;
 677
 678         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 679                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 680                 return -EPERM;
 681         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 682         if (!retval) {
 683                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 684                 wake_up(&stream->runtime->sleep);
 685                 stream->runtime->total_bytes_available = 0;
 686                 stream->runtime->total_bytes_transferred = 0;
 687         }
 688         return retval;
 689 }
 690
 691 static int snd_compr_drain(struct snd_compr_stream *stream)
 692 {
 693         int retval;
 694
 695         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 696                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 697                 return -EPERM;
 698         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 699         if (!retval) {
 700                 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 701                 wake_up(&stream->runtime->sleep);
 702         }
 703         return retval;
 704 }
 705
 706 static int snd_compr_next_track(struct snd_compr_stream *stream)
 707 {
 708         int retval;
 709
 710         /* only a running stream can transition to next track */
 711         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 712                 return -EPERM;
 713
 714         /* you can signal next track isf this is intended to be a gapless stream
 715          * and current track metadata is set
 716          */
 717         if (stream->metadata_set == false)
 718                 return -EPERM;
 719
 720         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 721         if (retval != 0)
 722                 return retval;
 723         stream->metadata_set = false;
 724         stream->next_track = true;
 725         return 0;
 726 }
 727
 728 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 729 {
 730         int retval;
 731         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 732                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 733                 return -EPERM;
 734         /* stream can be drained only when next track has been signalled */
 735         if (stream->next_track == false)
 736                 return -EPERM;
 737
 738         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 739
 740         stream->next_track = false;
 741         return retval;
 742 }
 743
 744 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 745 {
 746         struct snd_compr_file *data = f->private_data;
 747         struct snd_compr_stream *stream;
 748         int retval = -ENOTTY;
 749
 750         if (snd_BUG_ON(!data))
 751                 return -EFAULT;
 752         stream = &data->stream;
 753         if (snd_BUG_ON(!stream))
 754                 return -EFAULT;
 755         mutex_lock(&stream->device->lock);
 756         switch (_IOC_NR(cmd)) {
 757         case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 758                 retval = put_user(SNDRV_COMPRESS_VERSION,
 759                                 (int __user *)arg) ? -EFAULT : 0;
 760                 break;
 761         case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 762                 retval = snd_compr_get_caps(stream, arg);
 763                 break;
 764         case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 765                 retval = snd_compr_get_codec_caps(stream, arg);
 766                 break;
 767         case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 768                 retval = snd_compr_set_params(stream, arg);
 769                 break;
 770         case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 771                 retval = snd_compr_get_params(stream, arg);
 772                 break;
 773         case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 774                 retval = snd_compr_set_metadata(stream, arg);
 775                 break;
 776         case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 777                 retval = snd_compr_get_metadata(stream, arg);
 778                 break;
 779         case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 780                 retval = snd_compr_tstamp(stream, arg);
 781                 break;
 782         case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 783                 retval = snd_compr_ioctl_avail(stream, arg);
 784                 break;
 785         case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 786                 retval = snd_compr_pause(stream);
 787                 break;
 788         case _IOC_NR(SNDRV_COMPRESS_RESUME):
 789                 retval = snd_compr_resume(stream);
 790                 break;
 791         case _IOC_NR(SNDRV_COMPRESS_START):
 792                 retval = snd_compr_start(stream);
 793                 break;
 794         case _IOC_NR(SNDRV_COMPRESS_STOP):
 795                 retval = snd_compr_stop(stream);
 796                 break;
 797         case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 798                 retval = snd_compr_drain(stream);
 799                 break;
 800         case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 801                 retval = snd_compr_partial_drain(stream);
 802                 break;
 803         case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 804                 retval = snd_compr_next_track(stream);
 805                 break;
 806
 807         }
 808         mutex_unlock(&stream->device->lock);
 809         return retval;
 810 }
 811
 812 static const struct file_operations snd_compr_file_ops = {
 813                 .owner =        THIS_MODULE,
 814                 .open =         snd_compr_open,
 815                 .release =      snd_compr_free,
 816                 .write =        snd_compr_write,
 817                 .read =         snd_compr_read,
 818                 .unlocked_ioctl = snd_compr_ioctl,
 819                 .mmap =         snd_compr_mmap,
 820                 .poll =         snd_compr_poll,
 821 };
 822
 823 static int snd_compress_dev_register(struct snd_device *device)
 824 {
 825         int ret = -EINVAL;
 826         char str[16];
 827         struct snd_compr *compr;
 828
 829         if (snd_BUG_ON(!device || !device->device_data))
 830                 return -EBADFD;
 831         compr = device->device_data;
 832
 833         sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
 834         pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
 835                         compr->direction);
 836         /* register compressed device */
 837         ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
 838                         compr->device, &snd_compr_file_ops, compr, str);
 839         if (ret < 0) {
 840                 pr_err("snd_register_device failed\n %d", ret);
 841                 return ret;
 842         }
 843         return ret;
 844
 845 }
 846
 847 static int snd_compress_dev_disconnect(struct snd_device *device)
 848 {
 849         struct snd_compr *compr;
 850
 851         compr = device->device_data;
 852         snd_unregister_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
 853                 compr->device);
 854         return 0;
 855 }
 856
 857 /*
 858  * snd_compress_new: create new compress device
 859  * @card: sound card pointer
 860  * @device: device number
 861  * @dirn: device direction, should be of type enum snd_compr_direction
 862  * @compr: compress device pointer
 863  */
 864 int snd_compress_new(struct snd_card *card, int device,
 865                         int dirn, struct snd_compr *compr)
 866 {
 867         static struct snd_device_ops ops = {
 868                 .dev_free = NULL,
 869                 .dev_register = snd_compress_dev_register,
 870                 .dev_disconnect = snd_compress_dev_disconnect,
 871         };
 872
 873         compr->card = card;
 874         compr->device = device;
 875         compr->direction = dirn;
 876         return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
 877 }
 878 EXPORT_SYMBOL_GPL(snd_compress_new);
 879
 880 static int snd_compress_add_device(struct snd_compr *device)
 881 {
 882         int ret;
 883
 884         if (!device->card)
 885                 return -EINVAL;
 886
 887         /* register the card */
 888         ret = snd_card_register(device->card);
 889         if (ret)
 890                 goto out;
 891         return 0;
 892
 893 out:
 894         pr_err("failed with %d\n", ret);
 895         return ret;
 896
 897 }
 898
 899 static int snd_compress_remove_device(struct snd_compr *device)
 900 {
 901         return snd_card_free(device->card);
 902 }
 903
 904 /**
 905  * snd_compress_register - register compressed device
 906  *
 907  * @device: compressed device to register
 908  */
 909 int snd_compress_register(struct snd_compr *device)
 910 {
 911         int retval;
 912
 913         if (device->name == NULL || device->dev == NULL || device->ops == NULL)
 914                 return -EINVAL;
 915
 916         pr_debug("Registering compressed device %s\n", device->name);
 917         if (snd_BUG_ON(!device->ops->open))
 918                 return -EINVAL;
 919         if (snd_BUG_ON(!device->ops->free))
 920                 return -EINVAL;
 921         if (snd_BUG_ON(!device->ops->set_params))
 922                 return -EINVAL;
 923         if (snd_BUG_ON(!device->ops->trigger))
 924                 return -EINVAL;
 925
 926         mutex_init(&device->lock);
 927
 928         /* register a compressed card */
 929         mutex_lock(&device_mutex);
 930         retval = snd_compress_add_device(device);
 931         mutex_unlock(&device_mutex);
 932         return retval;
 933 }
 934 EXPORT_SYMBOL_GPL(snd_compress_register);
 935
 936 int snd_compress_deregister(struct snd_compr *device)
 937 {
 938         pr_debug("Removing compressed device %s\n", device->name);
 939         mutex_lock(&device_mutex);
 940         snd_compress_remove_device(device);
 941         mutex_unlock(&device_mutex);
 942         return 0;
 943 }
 944 EXPORT_SYMBOL_GPL(snd_compress_deregister);
 945
 946 static int __init snd_compress_init(void)
 947 {
 948         return 0;
 949 }
 950
 951 static void __exit snd_compress_exit(void)
 952 {
 953 }
 954
 955 module_init(snd_compress_init);
 956 module_exit(snd_compress_exit);
 957
 958 MODULE_DESCRIPTION("ALSA Compressed offload framework");
 959 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
 960 MODULE_LICENSE("GPL v2");