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 <linux/compat.h>
  42 #include <sound/core.h>
  43 #include <sound/initval.h>
  44 #include <sound/compress_params.h>
  45 #include <sound/compress_offload.h>
  46 #include <sound/compress_driver.h>
  47
  48 /* struct snd_compr_codec_caps overflows the ioctl bit size for some
  49  * architectures, so we need to disable the relevant ioctls.
  50  */
  51 #if _IOC_SIZEBITS < 14
  52 #define COMPR_CODEC_CAPS_OVERFLOW
  53 #endif
  54
  55 /* TODO:
  56  * - add substream support for multiple devices in case of
  57  *      SND_DYNAMIC_MINORS is not used
  58  * - Multiple node representation
  59  *      driver should be able to register multiple nodes
  60  */
  61
  62 static DEFINE_MUTEX(device_mutex);
  63
  64 struct snd_compr_file {
  65         unsigned long caps;
  66         struct snd_compr_stream stream;
  67 };
  68
  69 /*
  70  * a note on stream states used:
  71  * we use follwing states in the compressed core
  72  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
  73  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
  74  *      calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
  75  *      state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
  76  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
  77  *      decoding/encoding and rendering/capturing data.
  78  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
  79  *      by calling SNDRV_COMPRESS_DRAIN.
  80  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
  81  *      SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
  82  *      SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
  83  */
  84 static int snd_compr_open(struct inode *inode, struct file *f)
  85 {
  86         struct snd_compr *compr;
  87         struct snd_compr_file *data;
  88         struct snd_compr_runtime *runtime;
  89         enum snd_compr_direction dirn;
  90         int maj = imajor(inode);
  91         int ret;
  92
  93         if ((f->f_flags & O_ACCMODE) == O_WRONLY)
  94                 dirn = SND_COMPRESS_PLAYBACK;
  95         else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
  96                 dirn = SND_COMPRESS_CAPTURE;
  97         else
  98                 return -EINVAL;
  99
 100         if (maj == snd_major)
 101                 compr = snd_lookup_minor_data(iminor(inode),
 102                                         SNDRV_DEVICE_TYPE_COMPRESS);
 103         else
 104                 return -EBADFD;
 105
 106         if (compr == NULL) {
 107                 pr_err("no device data!!!\n");
 108                 return -ENODEV;
 109         }
 110
 111         if (dirn != compr->direction) {
 112                 pr_err("this device doesn't support this direction\n");
 113                 snd_card_unref(compr->card);
 114                 return -EINVAL;
 115         }
 116
 117         data = kzalloc(sizeof(*data), GFP_KERNEL);
 118         if (!data) {
 119                 snd_card_unref(compr->card);
 120                 return -ENOMEM;
 121         }
 122         data->stream.ops = compr->ops;
 123         data->stream.direction = dirn;
 124         data->stream.private_data = compr->private_data;
 125         data->stream.device = compr;
 126         runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 127         if (!runtime) {
 128                 kfree(data);
 129                 snd_card_unref(compr->card);
 130                 return -ENOMEM;
 131         }
 132         runtime->state = SNDRV_PCM_STATE_OPEN;
 133         init_waitqueue_head(&runtime->sleep);
 134         data->stream.runtime = runtime;
 135         f->private_data = (void *)data;
 136         mutex_lock(&compr->lock);
 137         ret = compr->ops->open(&data->stream);
 138         mutex_unlock(&compr->lock);
 139         if (ret) {
 140                 kfree(runtime);
 141                 kfree(data);
 142         }
 143         snd_card_unref(compr->card);
 144         return ret;
 145 }
 146
 147 static int snd_compr_free(struct inode *inode, struct file *f)
 148 {
 149         struct snd_compr_file *data = f->private_data;
 150         struct snd_compr_runtime *runtime = data->stream.runtime;
 151
 152         switch (runtime->state) {
 153         case SNDRV_PCM_STATE_RUNNING:
 154         case SNDRV_PCM_STATE_DRAINING:
 155         case SNDRV_PCM_STATE_PAUSED:
 156                 data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
 157                 break;
 158         default:
 159                 break;
 160         }
 161
 162         data->stream.ops->free(&data->stream);
 163         kfree(data->stream.runtime->buffer);
 164         kfree(data->stream.runtime);
 165         kfree(data);
 166         return 0;
 167 }
 168
 169 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 170                 struct snd_compr_tstamp *tstamp)
 171 {
 172         if (!stream->ops->pointer)
 173                 return -ENOTSUPP;
 174         stream->ops->pointer(stream, tstamp);
 175         pr_debug("dsp consumed till %d total %d bytes\n",
 176                 tstamp->byte_offset, tstamp->copied_total);
 177         if (stream->direction == SND_COMPRESS_PLAYBACK)
 178                 stream->runtime->total_bytes_transferred = tstamp->copied_total;
 179         else
 180                 stream->runtime->total_bytes_available = tstamp->copied_total;
 181         return 0;
 182 }
 183
 184 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
 185                 struct snd_compr_avail *avail)
 186 {
 187         memset(avail, 0, sizeof(*avail));
 188         snd_compr_update_tstamp(stream, &avail->tstamp);
 189         /* Still need to return avail even if tstamp can't be filled in */
 190
 191         if (stream->runtime->total_bytes_available == 0 &&
 192                         stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
 193                         stream->direction == SND_COMPRESS_PLAYBACK) {
 194                 pr_debug("detected init and someone forgot to do a write\n");
 195                 return stream->runtime->buffer_size;
 196         }
 197         pr_debug("app wrote %lld, DSP consumed %lld\n",
 198                         stream->runtime->total_bytes_available,
 199                         stream->runtime->total_bytes_transferred);
 200         if (stream->runtime->total_bytes_available ==
 201                                 stream->runtime->total_bytes_transferred) {
 202                 if (stream->direction == SND_COMPRESS_PLAYBACK) {
 203                         pr_debug("both pointers are same, returning full avail\n");
 204                         return stream->runtime->buffer_size;
 205                 } else {
 206                         pr_debug("both pointers are same, returning no avail\n");
 207                         return 0;
 208                 }
 209         }
 210
 211         avail->avail = stream->runtime->total_bytes_available -
 212                         stream->runtime->total_bytes_transferred;
 213         if (stream->direction == SND_COMPRESS_PLAYBACK)
 214                 avail->avail = stream->runtime->buffer_size - avail->avail;
 215
 216         pr_debug("ret avail as %lld\n", avail->avail);
 217         return avail->avail;
 218 }
 219
 220 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 221 {
 222         struct snd_compr_avail avail;
 223
 224         return snd_compr_calc_avail(stream, &avail);
 225 }
 226
 227 static int
 228 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
 229 {
 230         struct snd_compr_avail ioctl_avail;
 231         size_t avail;
 232
 233         avail = snd_compr_calc_avail(stream, &ioctl_avail);
 234         ioctl_avail.avail = avail;
 235
 236         if (copy_to_user((__u64 __user *)arg,
 237                                 &ioctl_avail, sizeof(ioctl_avail)))
 238                 return -EFAULT;
 239         return 0;
 240 }
 241
 242 static int snd_compr_write_data(struct snd_compr_stream *stream,
 243                const char __user *buf, size_t count)
 244 {
 245         void *dstn;
 246         size_t copy;
 247         struct snd_compr_runtime *runtime = stream->runtime;
 248         /* 64-bit Modulus */
 249         u64 app_pointer = div64_u64(runtime->total_bytes_available,
 250                                     runtime->buffer_size);
 251         app_pointer = runtime->total_bytes_available -
 252                       (app_pointer * runtime->buffer_size);
 253
 254         dstn = runtime->buffer + app_pointer;
 255         pr_debug("copying %ld at %lld\n",
 256                         (unsigned long)count, app_pointer);
 257         if (count < runtime->buffer_size - app_pointer) {
 258                 if (copy_from_user(dstn, buf, count))
 259                         return -EFAULT;
 260         } else {
 261                 copy = runtime->buffer_size - app_pointer;
 262                 if (copy_from_user(dstn, buf, copy))
 263                         return -EFAULT;
 264                 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
 265                         return -EFAULT;
 266         }
 267         /* if DSP cares, let it know data has been written */
 268         if (stream->ops->ack)
 269                 stream->ops->ack(stream, count);
 270         return count;
 271 }
 272
 273 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
 274                 size_t count, loff_t *offset)
 275 {
 276         struct snd_compr_file *data = f->private_data;
 277         struct snd_compr_stream *stream;
 278         size_t avail;
 279         int retval;
 280
 281         if (snd_BUG_ON(!data))
 282                 return -EFAULT;
 283
 284         stream = &data->stream;
 285         mutex_lock(&stream->device->lock);
 286         /* write is allowed when stream is running or has been steup */
 287         if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 288                         stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 289                 mutex_unlock(&stream->device->lock);
 290                 return -EBADFD;
 291         }
 292
 293         avail = snd_compr_get_avail(stream);
 294         pr_debug("avail returned %ld\n", (unsigned long)avail);
 295         /* calculate how much we can write to buffer */
 296         if (avail > count)
 297                 avail = count;
 298
 299         if (stream->ops->copy) {
 300                 char __user* cbuf = (char __user*)buf;
 301                 retval = stream->ops->copy(stream, cbuf, avail);
 302         } else {
 303                 retval = snd_compr_write_data(stream, buf, avail);
 304         }
 305         if (retval > 0)
 306                 stream->runtime->total_bytes_available += retval;
 307
 308         /* while initiating the stream, write should be called before START
 309          * call, so in setup move state */
 310         if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
 311                 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 312                 pr_debug("stream prepared, Houston we are good to go\n");
 313         }
 314
 315         mutex_unlock(&stream->device->lock);
 316         return retval;
 317 }
 318
 319
 320 static ssize_t snd_compr_read(struct file *f, char __user *buf,
 321                 size_t count, loff_t *offset)
 322 {
 323         struct snd_compr_file *data = f->private_data;
 324         struct snd_compr_stream *stream;
 325         size_t avail;
 326         int retval;
 327
 328         if (snd_BUG_ON(!data))
 329                 return -EFAULT;
 330
 331         stream = &data->stream;
 332         mutex_lock(&stream->device->lock);
 333
 334         /* read is allowed when stream is running, paused, draining and setup
 335          * (yes setup is state which we transition to after stop, so if user
 336          * wants to read data after stop we allow that)
 337          */
 338         switch (stream->runtime->state) {
 339         case SNDRV_PCM_STATE_OPEN:
 340         case SNDRV_PCM_STATE_PREPARED:
 341         case SNDRV_PCM_STATE_XRUN:
 342         case SNDRV_PCM_STATE_SUSPENDED:
 343         case SNDRV_PCM_STATE_DISCONNECTED:
 344                 retval = -EBADFD;
 345                 goto out;
 346         }
 347
 348         avail = snd_compr_get_avail(stream);
 349         pr_debug("avail returned %ld\n", (unsigned long)avail);
 350         /* calculate how much we can read from buffer */
 351         if (avail > count)
 352                 avail = count;
 353
 354         if (stream->ops->copy) {
 355                 retval = stream->ops->copy(stream, buf, avail);
 356         } else {
 357                 retval = -ENXIO;
 358                 goto out;
 359         }
 360         if (retval > 0)
 361                 stream->runtime->total_bytes_transferred += retval;
 362
 363 out:
 364         mutex_unlock(&stream->device->lock);
 365         return retval;
 366 }
 367
 368 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
 369 {
 370         return -ENXIO;
 371 }
 372
 373 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
 374 {
 375         if (stream->direction == SND_COMPRESS_PLAYBACK)
 376                 return POLLOUT | POLLWRNORM;
 377         else
 378                 return POLLIN | POLLRDNORM;
 379 }
 380
 381 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
 382 {
 383         struct snd_compr_file *data = f->private_data;
 384         struct snd_compr_stream *stream;
 385         size_t avail;
 386         int retval = 0;
 387
 388         if (snd_BUG_ON(!data))
 389                 return -EFAULT;
 390         stream = &data->stream;
 391         if (snd_BUG_ON(!stream))
 392                 return -EFAULT;
 393
 394         mutex_lock(&stream->device->lock);
 395         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 396                 retval = -EBADFD;
 397                 goto out;
 398         }
 399         poll_wait(f, &stream->runtime->sleep, wait);
 400
 401         avail = snd_compr_get_avail(stream);
 402         pr_debug("avail is %ld\n", (unsigned long)avail);
 403         /* check if we have at least one fragment to fill */
 404         switch (stream->runtime->state) {
 405         case SNDRV_PCM_STATE_DRAINING:
 406                 /* stream has been woken up after drain is complete
 407                  * draining done so set stream state to stopped
 408                  */
 409                 retval = snd_compr_get_poll(stream);
 410                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 411                 break;
 412         case SNDRV_PCM_STATE_RUNNING:
 413         case SNDRV_PCM_STATE_PREPARED:
 414         case SNDRV_PCM_STATE_PAUSED:
 415                 if (avail >= stream->runtime->fragment_size)
 416                         retval = snd_compr_get_poll(stream);
 417                 break;
 418         default:
 419                 if (stream->direction == SND_COMPRESS_PLAYBACK)
 420                         retval = POLLOUT | POLLWRNORM | POLLERR;
 421                 else
 422                         retval = POLLIN | POLLRDNORM | POLLERR;
 423                 break;
 424         }
 425 out:
 426         mutex_unlock(&stream->device->lock);
 427         return retval;
 428 }
 429
 430 static int
 431 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 432 {
 433         int retval;
 434         struct snd_compr_caps caps;
 435
 436         if (!stream->ops->get_caps)
 437                 return -ENXIO;
 438
 439         memset(&caps, 0, sizeof(caps));
 440         retval = stream->ops->get_caps(stream, &caps);
 441         if (retval)
 442                 goto out;
 443         if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 444                 retval = -EFAULT;
 445 out:
 446         return retval;
 447 }
 448
 449 #ifndef COMPR_CODEC_CAPS_OVERFLOW
 450 static int
 451 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 452 {
 453         int retval;
 454         struct snd_compr_codec_caps *caps;
 455
 456         if (!stream->ops->get_codec_caps)
 457                 return -ENXIO;
 458
 459         caps = kzalloc(sizeof(*caps), GFP_KERNEL);
 460         if (!caps)
 461                 return -ENOMEM;
 462
 463         retval = stream->ops->get_codec_caps(stream, caps);
 464         if (retval)
 465                 goto out;
 466         if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 467                 retval = -EFAULT;
 468
 469 out:
 470         kfree(caps);
 471         return retval;
 472 }
 473 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
 474
 475 /* revisit this with snd_pcm_preallocate_xxx */
 476 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 477                 struct snd_compr_params *params)
 478 {
 479         unsigned int buffer_size;
 480         void *buffer;
 481
 482         buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 483         if (stream->ops->copy) {
 484                 buffer = NULL;
 485                 /* if copy is defined the driver will be required to copy
 486                  * the data from core
 487                  */
 488         } else {
 489                 buffer = kmalloc(buffer_size, GFP_KERNEL);
 490                 if (!buffer)
 491                         return -ENOMEM;
 492         }
 493         stream->runtime->fragment_size = params->buffer.fragment_size;
 494         stream->runtime->fragments = params->buffer.fragments;
 495         stream->runtime->buffer = buffer;
 496         stream->runtime->buffer_size = buffer_size;
 497         return 0;
 498 }
 499
 500 static int snd_compress_check_input(struct snd_compr_params *params)
 501 {
 502         /* first let's check the buffer parameter's */
 503         if (params->buffer.fragment_size == 0 ||
 504             params->buffer.fragments > U32_MAX / params->buffer.fragment_size ||
 505             params->buffer.fragments == 0)
 506                 return -EINVAL;
 507
 508         /* now codec parameters */
 509         if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 510                 return -EINVAL;
 511
 512         if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 513                 return -EINVAL;
 514
 515         return 0;
 516 }
 517
 518 static int
 519 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 520 {
 521         struct snd_compr_params *params;
 522         int retval;
 523
 524         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 525                 /*
 526                  * we should allow parameter change only when stream has been
 527                  * opened not in other cases
 528                  */
 529                 params = kmalloc(sizeof(*params), GFP_KERNEL);
 530                 if (!params)
 531                         return -ENOMEM;
 532                 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 533                         retval = -EFAULT;
 534                         goto out;
 535                 }
 536
 537                 retval = snd_compress_check_input(params);
 538                 if (retval)
 539                         goto out;
 540
 541                 retval = snd_compr_allocate_buffer(stream, params);
 542                 if (retval) {
 543                         retval = -ENOMEM;
 544                         goto out;
 545                 }
 546
 547                 retval = stream->ops->set_params(stream, params);
 548                 if (retval)
 549                         goto out;
 550
 551                 stream->metadata_set = false;
 552                 stream->next_track = false;
 553
 554                 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 555         } else {
 556                 return -EPERM;
 557         }
 558 out:
 559         kfree(params);
 560         return retval;
 561 }
 562
 563 static int
 564 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 565 {
 566         struct snd_codec *params;
 567         int retval;
 568
 569         if (!stream->ops->get_params)
 570                 return -EBADFD;
 571
 572         params = kzalloc(sizeof(*params), GFP_KERNEL);
 573         if (!params)
 574                 return -ENOMEM;
 575         retval = stream->ops->get_params(stream, params);
 576         if (retval)
 577                 goto out;
 578         if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 579                 retval = -EFAULT;
 580
 581 out:
 582         kfree(params);
 583         return retval;
 584 }
 585
 586 static int
 587 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 588 {
 589         struct snd_compr_metadata metadata;
 590         int retval;
 591
 592         if (!stream->ops->get_metadata)
 593                 return -ENXIO;
 594
 595         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 596                 return -EFAULT;
 597
 598         retval = stream->ops->get_metadata(stream, &metadata);
 599         if (retval != 0)
 600                 return retval;
 601
 602         if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 603                 return -EFAULT;
 604
 605         return 0;
 606 }
 607
 608 static int
 609 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 610 {
 611         struct snd_compr_metadata metadata;
 612         int retval;
 613
 614         if (!stream->ops->set_metadata)
 615                 return -ENXIO;
 616         /*
 617         * we should allow parameter change only when stream has been
 618         * opened not in other cases
 619         */
 620         if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 621                 return -EFAULT;
 622
 623         retval = stream->ops->set_metadata(stream, &metadata);
 624         stream->metadata_set = true;
 625
 626         return retval;
 627 }
 628
 629 static inline int
 630 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 631 {
 632         struct snd_compr_tstamp tstamp = {0};
 633         int ret;
 634
 635         ret = snd_compr_update_tstamp(stream, &tstamp);
 636         if (ret == 0)
 637                 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 638                         &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 639         return ret;
 640 }
 641
 642 static int snd_compr_pause(struct snd_compr_stream *stream)
 643 {
 644         int retval;
 645
 646         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 647                 return -EPERM;
 648         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 649         if (!retval)
 650                 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 651         return retval;
 652 }
 653
 654 static int snd_compr_resume(struct snd_compr_stream *stream)
 655 {
 656         int retval;
 657
 658         if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 659                 return -EPERM;
 660         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 661         if (!retval)
 662                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 663         return retval;
 664 }
 665
 666 static int snd_compr_start(struct snd_compr_stream *stream)
 667 {
 668         int retval;
 669
 670         switch (stream->runtime->state) {
 671         case SNDRV_PCM_STATE_SETUP:
 672                 if (stream->direction != SND_COMPRESS_CAPTURE)
 673                         return -EPERM;
 674                 break;
 675         case SNDRV_PCM_STATE_PREPARED:
 676                 break;
 677         default:
 678                 return -EPERM;
 679         }
 680
 681         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 682         if (!retval)
 683                 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 684         return retval;
 685 }
 686
 687 static int snd_compr_stop(struct snd_compr_stream *stream)
 688 {
 689         int retval;
 690
 691         switch (stream->runtime->state) {
 692         case SNDRV_PCM_STATE_OPEN:
 693         case SNDRV_PCM_STATE_SETUP:
 694         case SNDRV_PCM_STATE_PREPARED:
 695                 return -EPERM;
 696         default:
 697                 break;
 698         }
 699
 700         retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 701         if (!retval) {
 702                 /* clear flags and stop any drain wait */
 703                 stream->partial_drain = false;
 704                 stream->metadata_set = false;
 705                 snd_compr_drain_notify(stream);
 706                 stream->runtime->total_bytes_available = 0;
 707                 stream->runtime->total_bytes_transferred = 0;
 708         }
 709         return retval;
 710 }
 711
 712 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
 713 {
 714         int ret;
 715
 716         /*
 717          * We are called with lock held. So drop the lock while we wait for
 718          * drain complete notfication from the driver
 719          *
 720          * It is expected that driver will notify the drain completion and then
 721          * stream will be moved to SETUP state, even if draining resulted in an
 722          * error. We can trigger next track after this.
 723          */
 724         stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 725         mutex_unlock(&stream->device->lock);
 726
 727         /* we wait for drain to complete here, drain can return when
 728          * interruption occurred, wait returned error or success.
 729          * For the first two cases we don't do anything different here and
 730          * return after waking up
 731          */
 732
 733         ret = wait_event_interruptible(stream->runtime->sleep,
 734                         (stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
 735         if (ret == -ERESTARTSYS)
 736                 pr_debug("wait aborted by a signal");
 737         else if (ret)
 738                 pr_debug("wait for drain failed with %d\n", ret);
 739
 740
 741         wake_up(&stream->runtime->sleep);
 742         mutex_lock(&stream->device->lock);
 743
 744         return ret;
 745 }
 746
 747 static int snd_compr_drain(struct snd_compr_stream *stream)
 748 {
 749         int retval;
 750
 751         switch (stream->runtime->state) {
 752         case SNDRV_PCM_STATE_OPEN:
 753         case SNDRV_PCM_STATE_SETUP:
 754         case SNDRV_PCM_STATE_PREPARED:
 755         case SNDRV_PCM_STATE_PAUSED:
 756                 return -EPERM;
 757         case SNDRV_PCM_STATE_XRUN:
 758                 return -EPIPE;
 759         default:
 760                 break;
 761         }
 762
 763         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 764         if (retval) {
 765                 pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
 766                 wake_up(&stream->runtime->sleep);
 767                 return retval;
 768         }
 769
 770         return snd_compress_wait_for_drain(stream);
 771 }
 772
 773 static int snd_compr_next_track(struct snd_compr_stream *stream)
 774 {
 775         int retval;
 776
 777         /* only a running stream can transition to next track */
 778         if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 779                 return -EPERM;
 780
 781         /* you can signal next track isf this is intended to be a gapless stream
 782          * and current track metadata is set
 783          */
 784         if (stream->metadata_set == false)
 785                 return -EPERM;
 786
 787         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 788         if (retval != 0)
 789                 return retval;
 790         stream->metadata_set = false;
 791         stream->next_track = true;
 792         return 0;
 793 }
 794
 795 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 796 {
 797         int retval;
 798
 799         switch (stream->runtime->state) {
 800         case SNDRV_PCM_STATE_OPEN:
 801         case SNDRV_PCM_STATE_SETUP:
 802         case SNDRV_PCM_STATE_PREPARED:
 803         case SNDRV_PCM_STATE_PAUSED:
 804                 return -EPERM;
 805         case SNDRV_PCM_STATE_XRUN:
 806                 return -EPIPE;
 807         default:
 808                 break;
 809         }
 810
 811         /* stream can be drained only when next track has been signalled */
 812         if (stream->next_track == false)
 813                 return -EPERM;
 814
 815         stream->partial_drain = true;
 816         retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 817         if (retval) {
 818                 pr_debug("Partial drain returned failure\n");
 819                 wake_up(&stream->runtime->sleep);
 820                 return retval;
 821         }
 822
 823         stream->next_track = false;
 824         return snd_compress_wait_for_drain(stream);
 825 }
 826
 827 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 828 {
 829         struct snd_compr_file *data = f->private_data;
 830         struct snd_compr_stream *stream;
 831         int retval = -ENOTTY;
 832
 833         if (snd_BUG_ON(!data))
 834                 return -EFAULT;
 835         stream = &data->stream;
 836         if (snd_BUG_ON(!stream))
 837                 return -EFAULT;
 838         mutex_lock(&stream->device->lock);
 839         switch (_IOC_NR(cmd)) {
 840         case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 841                 retval = put_user(SNDRV_COMPRESS_VERSION,
 842                                 (int __user *)arg) ? -EFAULT : 0;
 843                 break;
 844         case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 845                 retval = snd_compr_get_caps(stream, arg);
 846                 break;
 847 #ifndef COMPR_CODEC_CAPS_OVERFLOW
 848         case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 849                 retval = snd_compr_get_codec_caps(stream, arg);
 850                 break;
 851 #endif
 852         case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 853                 retval = snd_compr_set_params(stream, arg);
 854                 break;
 855         case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 856                 retval = snd_compr_get_params(stream, arg);
 857                 break;
 858         case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 859                 retval = snd_compr_set_metadata(stream, arg);
 860                 break;
 861         case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 862                 retval = snd_compr_get_metadata(stream, arg);
 863                 break;
 864         case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 865                 retval = snd_compr_tstamp(stream, arg);
 866                 break;
 867         case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 868                 retval = snd_compr_ioctl_avail(stream, arg);
 869                 break;
 870         case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 871                 retval = snd_compr_pause(stream);
 872                 break;
 873         case _IOC_NR(SNDRV_COMPRESS_RESUME):
 874                 retval = snd_compr_resume(stream);
 875                 break;
 876         case _IOC_NR(SNDRV_COMPRESS_START):
 877                 retval = snd_compr_start(stream);
 878                 break;
 879         case _IOC_NR(SNDRV_COMPRESS_STOP):
 880                 retval = snd_compr_stop(stream);
 881                 break;
 882         case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 883                 retval = snd_compr_drain(stream);
 884                 break;
 885         case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 886                 retval = snd_compr_partial_drain(stream);
 887                 break;
 888         case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 889                 retval = snd_compr_next_track(stream);
 890                 break;
 891
 892         }
 893         mutex_unlock(&stream->device->lock);
 894         return retval;
 895 }
 896
 897 /* support of 32bit userspace on 64bit platforms */
 898 #ifdef CONFIG_COMPAT
 899 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
 900                                                 unsigned long arg)
 901 {
 902         return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 903 }
 904 #endif
 905
 906 static const struct file_operations snd_compr_file_ops = {
 907                 .owner =        THIS_MODULE,
 908                 .open =         snd_compr_open,
 909                 .release =      snd_compr_free,
 910                 .write =        snd_compr_write,
 911                 .read =         snd_compr_read,
 912                 .unlocked_ioctl = snd_compr_ioctl,
 913 #ifdef CONFIG_COMPAT
 914                 .compat_ioctl = snd_compr_ioctl_compat,
 915 #endif
 916                 .mmap =         snd_compr_mmap,
 917                 .poll =         snd_compr_poll,
 918 };
 919
 920 static int snd_compress_dev_register(struct snd_device *device)
 921 {
 922         int ret = -EINVAL;
 923         struct snd_compr *compr;
 924
 925         if (snd_BUG_ON(!device || !device->device_data))
 926                 return -EBADFD;
 927         compr = device->device_data;
 928
 929         pr_debug("reg device %s, direction %d\n", compr->name,
 930                         compr->direction);
 931         /* register compressed device */
 932         ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
 933                                   compr->card, compr->device,
 934                                   &snd_compr_file_ops, compr, &compr->dev);
 935         if (ret < 0) {
 936                 pr_err("snd_register_device failed\n %d", ret);
 937                 return ret;
 938         }
 939         return ret;
 940
 941 }
 942
 943 static int snd_compress_dev_disconnect(struct snd_device *device)
 944 {
 945         struct snd_compr *compr;
 946
 947         compr = device->device_data;
 948         snd_unregister_device(&compr->dev);
 949         return 0;
 950 }
 951
 952 static int snd_compress_dev_free(struct snd_device *device)
 953 {
 954         struct snd_compr *compr;
 955
 956         compr = device->device_data;
 957         put_device(&compr->dev);
 958         return 0;
 959 }
 960
 961 /*
 962  * snd_compress_new: create new compress device
 963  * @card: sound card pointer
 964  * @device: device number
 965  * @dirn: device direction, should be of type enum snd_compr_direction
 966  * @compr: compress device pointer
 967  */
 968 int snd_compress_new(struct snd_card *card, int device,
 969                         int dirn, struct snd_compr *compr)
 970 {
 971         static struct snd_device_ops ops = {
 972                 .dev_free = snd_compress_dev_free,
 973                 .dev_register = snd_compress_dev_register,
 974                 .dev_disconnect = snd_compress_dev_disconnect,
 975         };
 976
 977         compr->card = card;
 978         compr->device = device;
 979         compr->direction = dirn;
 980
 981         snd_device_initialize(&compr->dev, card);
 982         dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
 983
 984         return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
 985 }
 986 EXPORT_SYMBOL_GPL(snd_compress_new);
 987
 988 static int snd_compress_add_device(struct snd_compr *device)
 989 {
 990         int ret;
 991
 992         if (!device->card)
 993                 return -EINVAL;
 994
 995         /* register the card */
 996         ret = snd_card_register(device->card);
 997         if (ret)
 998                 goto out;
 999         return 0;
1000
1001 out:
1002         pr_err("failed with %d\n", ret);
1003         return ret;
1004
1005 }
1006
1007 static int snd_compress_remove_device(struct snd_compr *device)
1008 {
1009         return snd_card_free(device->card);
1010 }
1011
1012 /**
1013  * snd_compress_register - register compressed device
1014  *
1015  * @device: compressed device to register
1016  */
1017 int snd_compress_register(struct snd_compr *device)
1018 {
1019         int retval;
1020
1021         if (device->name == NULL || device->ops == NULL)
1022                 return -EINVAL;
1023
1024         pr_debug("Registering compressed device %s\n", device->name);
1025         if (snd_BUG_ON(!device->ops->open))
1026                 return -EINVAL;
1027         if (snd_BUG_ON(!device->ops->free))
1028                 return -EINVAL;
1029         if (snd_BUG_ON(!device->ops->set_params))
1030                 return -EINVAL;
1031         if (snd_BUG_ON(!device->ops->trigger))
1032                 return -EINVAL;
1033
1034         mutex_init(&device->lock);
1035
1036         /* register a compressed card */
1037         mutex_lock(&device_mutex);
1038         retval = snd_compress_add_device(device);
1039         mutex_unlock(&device_mutex);
1040         return retval;
1041 }
1042 EXPORT_SYMBOL_GPL(snd_compress_register);
1043
1044 int snd_compress_deregister(struct snd_compr *device)
1045 {
1046         pr_debug("Removing compressed device %s\n", device->name);
1047         mutex_lock(&device_mutex);
1048         snd_compress_remove_device(device);
1049         mutex_unlock(&device_mutex);
1050         return 0;
1051 }
1052 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1053
1054 static int __init snd_compress_init(void)
1055 {
1056         return 0;
1057 }
1058
1059 static void __exit snd_compress_exit(void)
1060 {
1061 }
1062
1063 module_init(snd_compress_init);
1064 module_exit(snd_compress_exit);
1065
1066 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1067 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1068 MODULE_LICENSE("GPL v2");