kernel/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 ret;
 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_OPEN) {
 388                 retval = -EBADFD;
 389                 goto out;
 390         }
 391         poll_wait(f, &stream->runtime->sleep, wait);
 392
 393         avail = snd_compr_get_avail(stream);
 394         pr_debug("avail is %ld\n", (unsigned long)avail);
 395         /* check if we have at least one fragment to fill */
 396         switch (stream->runtime->state) {
 397         case SNDRV_PCM_STATE_DRAINING:
 398                 /* stream has been woken up after drain is complete
 399                  * draining done so set stream state to stopped
 400                  */
 401                 retval = snd_compr_get_poll(stream);
 402                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 403                 break;
 404         case SNDRV_PCM_STATE_RUNNING:
 405         case SNDRV_PCM_STATE_PREPARED:
 406         case SNDRV_PCM_STATE_PAUSED:
 407                 if (avail >= stream->runtime->fragment_size)
 408                         retval = snd_compr_get_poll(stream);
 409                 break;
 410         default:
 411                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 412                         retval = POLLOUT | POLLWRNORM | POLLERR;
 413                 else
 414                         retval = POLLIN | POLLRDNORM | POLLERR;
 415                 break;
 416         }
 417 out:
 418         mutex_unlock(&stream->device->lock);
 419         return retval;
 420 }
 421
 422 static int
 423 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 424 {
 425         int retval;
 426         struct snd_compr_caps caps;
 427
 428         if (!stream->ops->get_caps)
 429                 return -ENXIO;
 430
 431         memset(&caps, 0, sizeof(caps));
 432         retval = stream->ops->get_caps(stream, &caps);
 433         if (retval)
 434                 goto out;
 435         if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 436                 retval = -EFAULT;
 437 out:
 438         return retval;
 439 }
 440
 441 static int
 442 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 443 {
 444         int retval;
 445         struct snd_compr_codec_caps *caps;
 446
 447         if (!stream->ops->get_codec_caps)
 448                 return -ENXIO;
 449
 450         caps = kzalloc(sizeof(*caps), GFP_KERNEL);
 451         if (!caps)
 452                 return -ENOMEM;
 453
 454         retval = stream->ops->get_codec_caps(stream, caps);
 455         if (retval)
 456                 goto out;
 457         if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 458                 retval = -EFAULT;
 459
 460 out:
 461         kfree(caps);
 462         return retval;
 463 }
 464
 465 /* revisit this with snd_pcm_preallocate_xxx */
 466 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 467                 struct snd_compr_params *params)
 468 {
 469         unsigned int buffer_size;
 470         void *buffer;
 471
 472         buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 473         if (stream->ops->copy) {
 474                 buffer = NULL;
 475                 /* if copy is defined the driver will be required to copy
 476                  * the data from core
 477                  */
 478         } else {
 479                 buffer = kmalloc(buffer_size, GFP_KERNEL);
 480                 if (!buffer)
 481                         return -ENOMEM;
 482         }
 483         stream->runtime->fragment_size = params->buffer.fragment_size;
 484         stream->runtime->fragments = params->buffer.fragments;
 485         stream->runtime->buffer = buffer;
 486         stream->runtime->buffer_size = buffer_size;
 487         return 0;
 488 }
 489
 490 static int snd_compress_check_input(struct snd_compr_params *params)
 491 {
 492         /* first let's check the buffer parameter's */
 493         if (params->buffer.fragment_size == 0 ||
 494             params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
 495                 return -EINVAL;
 496
 497         /* now codec parameters */
 498         if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 499                 return -EINVAL;
 500
 501         if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 502                 return -EINVAL;
 503
 504         return 0;
 505 }
 506
 507 static int
 508 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 509 {
 510         struct snd_compr_params *params;
 511         int retval;
 512
 513         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 514                 /*
 515                  * we should allow parameter change only when stream has been
 516                  * opened not in other cases
 517                  */
 518                 params = kmalloc(sizeof(*params), GFP_KERNEL);
 519                 if (!params)
 520                         return -ENOMEM;
 521                 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 522                         retval = -EFAULT;
 523                         goto out;
 524                 }
 525
 526                 retval = snd_compress_check_input(params);
 527                 if (retval)
 528                         goto out;
 529
 530                 retval = snd_compr_allocate_buffer(stream, params);
 531                 if (retval) {
 532                         retval = -ENOMEM;
 533                         goto out;
 534                 }
 535
 536                 retval = stream->ops->set_params(stream, params);
 537                 if (retval)
 538                         goto out;
 539
 540                 stream->metadata_set = false;
 541                 stream->next_track = false;
 542
 543                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 544                         stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 545                 else
 546                         stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 547         } else {
 548                 return -EPERM;
 549         }
 550 out:
 551         kfree(params);
 552         return retval;
 553 }
 554
 555 static int
 556 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 557 {
 558         struct snd_codec *params;
 559         int retval;
 560
 561         if (!stream->ops->get_params)
 562                 return -EBADFD;
 563
 564         params = kzalloc(sizeof(*params), GFP_KERNEL);
 565         if (!params)
 566                 return -ENOMEM;
 567         retval = stream->ops->get_params(stream, params);
 568         if (retval)
 569                 goto out;
 570         if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 571                 retval = -EFAULT;
 572
 573 out:
 574         kfree(params);
 575         return retval;
 576 }
 577
 578 static int
 579 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 580 {
 581         struct snd_compr_metadata metadata;
 582         int retval;
 583
 584         if (!stream->ops->get_metadata)
 585                 return -ENXIO;
 586
 587         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 588                 return -EFAULT;
 589
 590         retval = stream->ops->get_metadata(stream, &metadata);
 591         if (retval != 0)
 592                 return retval;
 593
 594         if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 595                 return -EFAULT;
 596
 597         return 0;
 598 }
 599
 600 static int
 601 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 602 {
 603         struct snd_compr_metadata metadata;
 604         int retval;
 605
 606         if (!stream->ops->set_metadata)
 607                 return -ENXIO;
 608         /*
 609         * we should allow parameter change only when stream has been
 610         * opened not in other cases
 611         */
 612         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 613                 return -EFAULT;
 614
 615         retval = stream->ops->set_metadata(stream, &metadata);
 616         stream->metadata_set = true;
 617
 618         return retval;
 619 }
 620
 621 static inline int
 622 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 623 {
 624         struct snd_compr_tstamp tstamp = {0};
 625         int ret;
 626
 627         ret = snd_compr_update_tstamp(stream, &tstamp);
 628         if (ret == 0)
 629                 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 630                         &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 631         return ret;
 632 }
 633
 634 static int snd_compr_pause(struct snd_compr_stream *stream)
 635 {
 636         int retval;
 637
 638         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 639                 return -EPERM;
 640         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 641         if (!retval)
 642                 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 643         return retval;
 644 }
 645
 646 static int snd_compr_resume(struct snd_compr_stream *stream)
 647 {
 648         int retval;
 649
 650         if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 651                 return -EPERM;
 652         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 653         if (!retval)
 654                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 655         return retval;
 656 }
 657
 658 static int snd_compr_start(struct snd_compr_stream *stream)
 659 {
 660         int retval;
 661
 662         if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
 663                 return -EPERM;
 664         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 665         if (!retval)
 666                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 667         return retval;
 668 }
 669
 670 static int snd_compr_stop(struct snd_compr_stream *stream)
 671 {
 672         int retval;
 673
 674         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 675                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 676                 return -EPERM;
 677         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 678         if (!retval) {
 679                 snd_compr_drain_notify(stream);
 680                 stream->runtime->total_bytes_available = 0;
 681                 stream->runtime->total_bytes_transferred = 0;
 682         }
 683         return retval;
 684 }
 685
 686 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
 687 {
 688         int ret;
 689
 690         /*
 691          * We are called with lock held. So drop the lock while we wait for
 692          * drain complete notfication from the driver
 693          *
 694          * It is expected that driver will notify the drain completion and then
 695          * stream will be moved to SETUP state, even if draining resulted in an
 696          * error. We can trigger next track after this.
 697          */
 698         stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 699         mutex_unlock(&stream->device->lock);
 700
 701         /* we wait for drain to complete here, drain can return when
 702          * interruption occurred, wait returned error or success.
 703          * For the first two cases we don't do anything different here and
 704          * return after waking up
 705          */
 706
 707         ret = wait_event_interruptible(stream->runtime->sleep,
 708                         (stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
 709         if (ret == -ERESTARTSYS)
 710                 pr_debug("wait aborted by a signal");
 711         else if (ret)
 712                 pr_debug("wait for drain failed with %d\n", ret);
 713
 714
 715         wake_up(&stream->runtime->sleep);
 716         mutex_lock(&stream->device->lock);
 717
 718         return ret;
 719 }
 720
 721 static int snd_compr_drain(struct snd_compr_stream *stream)
 722 {
 723         int retval;
 724
 725         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 726                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 727                 return -EPERM;
 728
 729         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 730         if (retval) {
 731                 pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
 732                 wake_up(&stream->runtime->sleep);
 733                 return retval;
 734         }
 735
 736         return snd_compress_wait_for_drain(stream);
 737 }
 738
 739 static int snd_compr_next_track(struct snd_compr_stream *stream)
 740 {
 741         int retval;
 742
 743         /* only a running stream can transition to next track */
 744         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 745                 return -EPERM;
 746
 747         /* you can signal next track isf this is intended to be a gapless stream
 748          * and current track metadata is set
 749          */
 750         if (stream->metadata_set == false)
 751                 return -EPERM;
 752
 753         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 754         if (retval != 0)
 755                 return retval;
 756         stream->metadata_set = false;
 757         stream->next_track = true;
 758         return 0;
 759 }
 760
 761 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 762 {
 763         int retval;
 764         if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 765                         stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 766                 return -EPERM;
 767         /* stream can be drained only when next track has been signalled */
 768         if (stream->next_track == false)
 769                 return -EPERM;
 770
 771         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 772         if (retval) {
 773                 pr_debug("Partial drain returned failure\n");
 774                 wake_up(&stream->runtime->sleep);
 775                 return retval;
 776         }
 777
 778         stream->next_track = false;
 779         return snd_compress_wait_for_drain(stream);
 780 }
 781
 782 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 783 {
 784         struct snd_compr_file *data = f->private_data;
 785         struct snd_compr_stream *stream;
 786         int retval = -ENOTTY;
 787
 788         if (snd_BUG_ON(!data))
 789                 return -EFAULT;
 790         stream = &data->stream;
 791         if (snd_BUG_ON(!stream))
 792                 return -EFAULT;
 793         mutex_lock(&stream->device->lock);
 794         switch (_IOC_NR(cmd)) {
 795         case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 796                 retval = put_user(SNDRV_COMPRESS_VERSION,
 797                                 (int __user *)arg) ? -EFAULT : 0;
 798                 break;
 799         case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 800                 retval = snd_compr_get_caps(stream, arg);
 801                 break;
 802         case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 803                 retval = snd_compr_get_codec_caps(stream, arg);
 804                 break;
 805         case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 806                 retval = snd_compr_set_params(stream, arg);
 807                 break;
 808         case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 809                 retval = snd_compr_get_params(stream, arg);
 810                 break;
 811         case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 812                 retval = snd_compr_set_metadata(stream, arg);
 813                 break;
 814         case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 815                 retval = snd_compr_get_metadata(stream, arg);
 816                 break;
 817         case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 818                 retval = snd_compr_tstamp(stream, arg);
 819                 break;
 820         case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 821                 retval = snd_compr_ioctl_avail(stream, arg);
 822                 break;
 823         case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 824                 retval = snd_compr_pause(stream);
 825                 break;
 826         case _IOC_NR(SNDRV_COMPRESS_RESUME):
 827                 retval = snd_compr_resume(stream);
 828                 break;
 829         case _IOC_NR(SNDRV_COMPRESS_START):
 830                 retval = snd_compr_start(stream);
 831                 break;
 832         case _IOC_NR(SNDRV_COMPRESS_STOP):
 833                 retval = snd_compr_stop(stream);
 834                 break;
 835         case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 836                 retval = snd_compr_drain(stream);
 837                 break;
 838         case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 839                 retval = snd_compr_partial_drain(stream);
 840                 break;
 841         case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 842                 retval = snd_compr_next_track(stream);
 843                 break;
 844
 845         }
 846         mutex_unlock(&stream->device->lock);
 847         return retval;
 848 }
 849
 850 static const struct file_operations snd_compr_file_ops = {
 851                 .owner =        THIS_MODULE,
 852                 .open =         snd_compr_open,
 853                 .release =      snd_compr_free,
 854                 .write =        snd_compr_write,
 855                 .read =         snd_compr_read,
 856                 .unlocked_ioctl = snd_compr_ioctl,
 857                 .mmap =         snd_compr_mmap,
 858                 .poll =         snd_compr_poll,
 859 };
 860
 861 static int snd_compress_dev_register(struct snd_device *device)
 862 {
 863         int ret = -EINVAL;
 864         char str[16];
 865         struct snd_compr *compr;
 866
 867         if (snd_BUG_ON(!device || !device->device_data))
 868                 return -EBADFD;
 869         compr = device->device_data;
 870
 871         pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
 872                         compr->direction);
 873         /* register compressed device */
 874         ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
 875                                   compr->card, compr->device,
 876                                   &snd_compr_file_ops, compr, &compr->dev);
 877         if (ret < 0) {
 878                 pr_err("snd_register_device failed\n %d", ret);
 879                 return ret;
 880         }
 881         return ret;
 882
 883 }
 884
 885 static int snd_compress_dev_disconnect(struct snd_device *device)
 886 {
 887         struct snd_compr *compr;
 888
 889         compr = device->device_data;
 890         snd_unregister_device(&compr->dev);
 891         return 0;
 892 }
 893
 894 static int snd_compress_dev_free(struct snd_device *device)
 895 {
 896         struct snd_compr *compr;
 897
 898         compr = device->device_data;
 899         put_device(&compr->dev);
 900         return 0;
 901 }
 902
 903 /*
 904  * snd_compress_new: create new compress device
 905  * @card: sound card pointer
 906  * @device: device number
 907  * @dirn: device direction, should be of type enum snd_compr_direction
 908  * @compr: compress device pointer
 909  */
 910 int snd_compress_new(struct snd_card *card, int device,
 911                         int dirn, struct snd_compr *compr)
 912 {
 913         static struct snd_device_ops ops = {
 914                 .dev_free = snd_compress_dev_free,
 915                 .dev_register = snd_compress_dev_register,
 916                 .dev_disconnect = snd_compress_dev_disconnect,
 917         };
 918
 919         compr->card = card;
 920         compr->device = device;
 921         compr->direction = dirn;
 922
 923         snd_device_initialize(&compr->dev, card);
 924         dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
 925
 926         return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
 927 }
 928 EXPORT_SYMBOL_GPL(snd_compress_new);
 929
 930 static int snd_compress_add_device(struct snd_compr *device)
 931 {
 932         int ret;
 933
 934         if (!device->card)
 935                 return -EINVAL;
 936
 937         /* register the card */
 938         ret = snd_card_register(device->card);
 939         if (ret)
 940                 goto out;
 941         return 0;
 942
 943 out:
 944         pr_err("failed with %d\n", ret);
 945         return ret;
 946
 947 }
 948
 949 static int snd_compress_remove_device(struct snd_compr *device)
 950 {
 951         return snd_card_free(device->card);
 952 }
 953
 954 /**
 955  * snd_compress_register - register compressed device
 956  *
 957  * @device: compressed device to register
 958  */
 959 int snd_compress_register(struct snd_compr *device)
 960 {
 961         int retval;
 962
 963         if (device->name == NULL || device->ops == NULL)
 964                 return -EINVAL;
 965
 966         pr_debug("Registering compressed device %s\n", device->name);
 967         if (snd_BUG_ON(!device->ops->open))
 968                 return -EINVAL;
 969         if (snd_BUG_ON(!device->ops->free))
 970                 return -EINVAL;
 971         if (snd_BUG_ON(!device->ops->set_params))
 972                 return -EINVAL;
 973         if (snd_BUG_ON(!device->ops->trigger))
 974                 return -EINVAL;
 975
 976         mutex_init(&device->lock);
 977
 978         /* register a compressed card */
 979         mutex_lock(&device_mutex);
 980         retval = snd_compress_add_device(device);
 981         mutex_unlock(&device_mutex);
 982         return retval;
 983 }
 984 EXPORT_SYMBOL_GPL(snd_compress_register);
 985
 986 int snd_compress_deregister(struct snd_compr *device)
 987 {
 988         pr_debug("Removing compressed device %s\n", device->name);
 989         mutex_lock(&device_mutex);
 990         snd_compress_remove_device(device);
 991         mutex_unlock(&device_mutex);
 992         return 0;
 993 }
 994 EXPORT_SYMBOL_GPL(snd_compress_deregister);
 995
 996 static int __init snd_compress_init(void)
 997 {
 998         return 0;
 999 }
1000
1001 static void __exit snd_compress_exit(void)
1002 {
1003 }
1004
1005 module_init(snd_compress_init);
1006 module_exit(snd_compress_exit);
1007
1008 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1009 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1010 MODULE_LICENSE("GPL v2");