blob: 48f2a1ff2bbc81036238751465d5b2fad3cc9eee [file] [log] [blame]
* compress_driver.h - compress offload driver definations
* Copyright (C) 2011 Intel Corporation
* Authors: Vinod Koul <>
* Pierre-Louis Bossart <>
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* 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
* 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.
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <linux/types.h>
#include <linux/sched.h>
#include <sound/compress_offload.h>
#include <sound/asound.h>
#include <sound/pcm.h>
struct snd_compr_ops;
* struct snd_compr_runtime: runtime stream description
* @state: stream state
* @ops: pointer to DSP callbacks
* @buffer: pointer to kernel buffer, valid only when not in mmap mode or
* DSP doesn't implement copy
* @buffer_size: size of the above buffer
* @fragment_size: size of buffer fragment in bytes
* @fragments: number of such fragments
* @hw_pointer: offset of last location in buffer where DSP copied data
* @app_pointer: offset of last location in buffer where app wrote data
* @total_bytes_available: cumulative number of bytes made available in
* the ring buffer
* @total_bytes_transferred: cumulative bytes transferred by offload DSP
* @sleep: poll sleep
struct snd_compr_runtime {
snd_pcm_state_t state;
struct snd_compr_ops *ops;
void *buffer;
u64 buffer_size;
u32 fragment_size;
u32 fragments;
u64 hw_pointer;
u64 app_pointer;
u64 total_bytes_available;
u64 total_bytes_transferred;
wait_queue_head_t sleep;
* struct snd_compr_stream: compressed stream
* @name: device name
* @ops: pointer to DSP callbacks
* @runtime: pointer to runtime structure
* @device: device pointer
* @direction: stream direction, playback/recording
* @private_data: pointer to DSP private data
struct snd_compr_stream {
const char *name;
struct snd_compr_ops *ops;
struct snd_compr_runtime *runtime;
struct snd_compr *device;
enum snd_compr_direction direction;
void *private_data;
* struct snd_compr_ops: compressed path DSP operations
* @open: Open the compressed stream
* This callback is mandatory and shall keep dsp ready to receive the stream
* parameter
* @free: Close the compressed stream, mandatory
* @set_params: Sets the compressed stream parameters, mandatory
* This can be called in during stream creation only to set codec params
* and the stream properties
* @get_params: retrieve the codec parameters, mandatory
* @trigger: Trigger operations like start, pause, resume, drain, stop.
* This callback is mandatory
* @pointer: Retrieve current h/w pointer information. Mandatory
* @copy: Copy the compressed data to/from userspace, Optional
* Can't be implemented if DSP supports mmap
* @mmap: DSP mmap method to mmap DSP memory
* @ack: Ack for DSP when data is written to audio buffer, Optional
* Not valid if copy is implemented
* @get_caps: Retrieve DSP capabilities, mandatory
* @get_codec_caps: Retrieve capabilities for a specific codec, mandatory
struct snd_compr_ops {
int (*open)(struct snd_compr_stream *stream);
int (*free)(struct snd_compr_stream *stream);
int (*set_params)(struct snd_compr_stream *stream,
struct snd_compr_params *params);
int (*get_params)(struct snd_compr_stream *stream,
struct snd_codec *params);
int (*trigger)(struct snd_compr_stream *stream, int cmd);
int (*pointer)(struct snd_compr_stream *stream,
struct snd_compr_tstamp *tstamp);
int (*copy)(struct snd_compr_stream *stream, const char __user *buf,
size_t count);
int (*mmap)(struct snd_compr_stream *stream,
struct vm_area_struct *vma);
int (*ack)(struct snd_compr_stream *stream, size_t bytes);
int (*get_caps) (struct snd_compr_stream *stream,
struct snd_compr_caps *caps);
int (*get_codec_caps) (struct snd_compr_stream *stream,
struct snd_compr_codec_caps *codec);
* struct snd_compr: Compressed device
* @name: DSP device name
* @dev: Device pointer
* @ops: pointer to DSP callbacks
* @private_data: pointer to DSP pvt data
* @card: sound card pointer
* @direction: Playback or capture direction
* @lock: device lock
* @device: device id
struct snd_compr {
const char *name;
struct device *dev;
struct snd_compr_ops *ops;
void *private_data;
struct snd_card *card;
unsigned int direction;
struct mutex lock;
int device;
/* compress device register APIs */
int snd_compress_register(struct snd_compr *device);
int snd_compress_deregister(struct snd_compr *device);
int snd_compress_new(struct snd_card *card, int device,
int type, struct snd_compr *compr);
/* dsp driver callback apis
* For playback: driver should call snd_compress_fragment_elapsed() to let the
* framework know that a fragment has been consumed from the ring buffer
* For recording: we want to know when a frame is available or when
* at least one frame is available so snd_compress_frame_elapsed()
* callback should be called when a encodeded frame is available
static inline void snd_compr_fragment_elapsed(struct snd_compr_stream *stream)