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|
/*
* compress_core.c - compress offload core
*
* Copyright (C) 2011 Intel Corporation
* Authors: Vinod Koul <vinod.koul@linux.intel.com>
* Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
*/
#define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
#define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/uio.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/compress_params.h>
#include <sound/compress_offload.h>
#include <sound/compress_driver.h>
/* TODO:
* - add substream support for multiple devices in case of
* SND_DYNAMIC_MINORS is not used
* - Multiple node representation
* driver should be able to register multiple nodes
*/
static DEFINE_MUTEX(device_mutex);
struct snd_compr_file {
unsigned long caps;
struct snd_compr_stream stream;
};
/*
* a note on stream states used:
* we use follwing states in the compressed core
* SNDRV_PCM_STATE_OPEN: When stream has been opened.
* SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
* calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
* state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
* SNDRV_PCM_STATE_RUNNING: When stream has been started and is
* decoding/encoding and rendering/capturing data.
* SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
* by calling SNDRV_COMPRESS_DRAIN.
* SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
* SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
* SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
*/
static int snd_compr_open(struct inode *inode, struct file *f)
{
struct snd_compr *compr;
struct snd_compr_file *data;
struct snd_compr_runtime *runtime;
enum snd_compr_direction dirn;
int maj = imajor(inode);
int ret;
if (f->f_flags & O_WRONLY)
dirn = SND_COMPRESS_PLAYBACK;
else if (f->f_flags & O_RDONLY)
dirn = SND_COMPRESS_CAPTURE;
else {
pr_err("invalid direction\n");
return -EINVAL;
}
if (maj == snd_major)
compr = snd_lookup_minor_data(iminor(inode),
SNDRV_DEVICE_TYPE_COMPRESS);
else
return -EBADFD;
if (compr == NULL) {
pr_err("no device data!!!\n");
return -ENODEV;
}
if (dirn != compr->direction) {
pr_err("this device doesn't support this direction\n");
return -EINVAL;
}
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->stream.ops = compr->ops;
data->stream.direction = dirn;
data->stream.private_data = compr->private_data;
data->stream.device = compr;
runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
if (!runtime) {
kfree(data);
return -ENOMEM;
}
runtime->state = SNDRV_PCM_STATE_OPEN;
init_waitqueue_head(&runtime->sleep);
data->stream.runtime = runtime;
f->private_data = (void *)data;
mutex_lock(&compr->lock);
ret = compr->ops->open(&data->stream);
mutex_unlock(&compr->lock);
if (ret) {
kfree(runtime);
kfree(data);
}
return ret;
}
static int snd_compr_free(struct inode *inode, struct file *f)
{
struct snd_compr_file *data = f->private_data;
data->stream.ops->free(&data->stream);
kfree(data->stream.runtime->buffer);
kfree(data->stream.runtime);
kfree(data);
return 0;
}
static void snd_compr_update_tstamp(struct snd_compr_stream *stream,
struct snd_compr_tstamp *tstamp)
{
if (!stream->ops->pointer)
return;
stream->ops->pointer(stream, tstamp);
pr_debug("dsp consumed till %d total %d bytes\n",
tstamp->byte_offset, tstamp->copied_total);
stream->runtime->hw_pointer = tstamp->byte_offset;
stream->runtime->total_bytes_transferred = tstamp->copied_total;
}
static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
struct snd_compr_avail *avail)
{
long avail_calc; /*this needs to be signed variable */
snd_compr_update_tstamp(stream, &avail->tstamp);
/* FIXME: This needs to be different for capture stream,
available is # of compressed data, for playback it's
remainder of buffer */
if (stream->runtime->total_bytes_available == 0 &&
stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
pr_debug("detected init and someone forgot to do a write\n");
return stream->runtime->buffer_size;
}
pr_debug("app wrote %lld, DSP consumed %lld\n",
stream->runtime->total_bytes_available,
stream->runtime->total_bytes_transferred);
if (stream->runtime->total_bytes_available ==
stream->runtime->total_bytes_transferred) {
pr_debug("both pointers are same, returning full avail\n");
return stream->runtime->buffer_size;
}
/* FIXME: this routine isn't consistent, in one test we use
* cumulative values and in the other byte offsets. Do we
* really need the byte offsets if the cumulative values have
* been updated? In the PCM interface app_ptr and hw_ptr are
* already cumulative */
avail_calc = stream->runtime->buffer_size -
(stream->runtime->app_pointer - stream->runtime->hw_pointer);
pr_debug("calc avail as %ld, app_ptr %lld, hw+ptr %lld\n", avail_calc,
stream->runtime->app_pointer,
stream->runtime->hw_pointer);
if (avail_calc >= stream->runtime->buffer_size)
avail_calc -= stream->runtime->buffer_size;
pr_debug("ret avail as %ld\n", avail_calc);
avail->avail = avail_calc;
return avail_calc;
}
static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
{
struct snd_compr_avail avail;
return snd_compr_calc_avail(stream, &avail);
}
static int
snd_compr_ioctl_avail(struct snd_compr_stream *stream,
|