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