blob: e87f2d5b3cc656c852d0892ff37f3d723dd3b46d [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0
* compress_driver.h - compress offload driver definations
* Copyright (C) 2011 Intel Corporation
* Authors: Vinod Koul <>
* Pierre-Louis Bossart <>
#include <linux/types.h>
#include <linux/sched.h>
#include <sound/core.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
* @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
* @private_data: driver private data pointer
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 total_bytes_available;
u64 total_bytes_transferred;
wait_queue_head_t sleep;
void *private_data;
* struct snd_compr_stream: compressed stream
* @name: device name
* @ops: pointer to DSP callbacks
* @runtime: pointer to runtime structure
* @device: device pointer
* @error_work: delayed work used when closing the stream due to an error
* @direction: stream direction, playback/recording
* @metadata_set: metadata set flag, true when set
* @next_track: has userspace signal next track transition, true when set
* @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;
struct delayed_work error_work;
enum snd_compr_direction direction;
bool metadata_set;
bool next_track;
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
* @set_metadata: Set the metadata values for a stream
* @get_metadata: retrieves the requested metadata values from stream
* @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 (*set_metadata)(struct snd_compr_stream *stream,
struct snd_compr_metadata *metadata);
int (*get_metadata)(struct snd_compr_stream *stream,
struct snd_compr_metadata *metadata);
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, 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: associated device instance
* @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;
/* private: */
char id[64];
struct snd_info_entry *proc_root;
struct snd_info_entry *proc_info_entry;
/* 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, const char *id, 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)
static inline void snd_compr_drain_notify(struct snd_compr_stream *stream)
if (snd_BUG_ON(!stream))
if (stream->direction == SND_COMPRESS_PLAYBACK)
stream->runtime->state = SNDRV_PCM_STATE_SETUP;
stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
int snd_compr_stop_error(struct snd_compr_stream *stream,
snd_pcm_state_t state);