blob: 96666efddb396b7c44d8be2be0fff12fdba829c2 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0+
* Copyright (C) 2012, Analog Devices Inc.
* Author: Lars-Peter Clausen <>
#include <sound/pcm.h>
#include <sound/soc.h>
#include <linux/dmaengine.h>
* snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
* substream
* @substream: PCM substream
static inline enum dma_transfer_direction
snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
return DMA_MEM_TO_DEV;
return DMA_DEV_TO_MEM;
int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
struct dma_chan *chan);
int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
dma_filter_fn filter_fn, void *filter_data);
int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
void *filter_data);
struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
* The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
* If this flag is set the dmaengine driver won't put any restriction on
* the supported sample formats and set the DMA transfer size to undefined.
* The DAI driver is responsible to disable any unsupported formats in it's
* configuration and catch corner cases that are not already handled in
* the ALSA core.
* struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
* @addr: Address of the DAI data source or destination register.
* @addr_width: Width of the DAI data source or destination register.
* @maxburst: Maximum number of words(note: words, as in units of the
* src_addr_width member, not bytes) that can be send to or received from the
* DAI in one burst.
* @slave_id: Slave requester id for the DMA channel.
* @filter_data: Custom DMA channel filter data, this will usually be used when
* requesting the DMA channel.
* @chan_name: Custom channel name to use when requesting DMA channel.
* @fifo_size: FIFO size of the DAI controller in bytes
* @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
* @peripheral_config: peripheral configuration for programming peripheral
* for dmaengine transfer
* @peripheral_size: peripheral configuration buffer size
struct snd_dmaengine_dai_dma_data {
dma_addr_t addr;
enum dma_slave_buswidth addr_width;
u32 maxburst;
unsigned int slave_id;
void *filter_data;
const char *chan_name;
unsigned int fifo_size;
unsigned int flags;
void *peripheral_config;
size_t peripheral_size;
void snd_dmaengine_pcm_set_config_from_dai_data(
const struct snd_pcm_substream *substream,
const struct snd_dmaengine_dai_dma_data *dma_data,
struct dma_slave_config *config);
int snd_dmaengine_pcm_refine_runtime_hwparams(
struct snd_pcm_substream *substream,
struct snd_dmaengine_dai_dma_data *dma_data,
struct snd_pcm_hardware *hw,
struct dma_chan *chan);
* Try to request the DMA channel using compat_request_channel or
* compat_filter_fn if it couldn't be requested through devicetree.
* Don't try to request the DMA channels through devicetree. This flag only
* makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
* The PCM is half duplex and the DMA channel is shared between capture and
* playback.
* struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
* @prepare_slave_config: Callback used to fill in the DMA slave_config for a
* PCM substream. Will be called from the PCM drivers hwparams callback.
* @compat_request_channel: Callback to request a DMA channel for platforms
* which do not use devicetree.
* @process: Callback used to apply processing on samples transferred from/to
* user space.
* @compat_filter_fn: Will be used as the filter function when requesting a
* channel for platforms which do not use devicetree. The filter parameter
* will be the DAI's DMA data.
* @dma_dev: If set, request DMA channel on this device rather than the DAI
* device.
* @chan_names: If set, these custom DMA channel names will be requested at
* registration time.
* @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
* @prealloc_buffer_size: Size of the preallocated audio buffer.
* Note: If both compat_request_channel and compat_filter_fn are set
* compat_request_channel will be used to request the channel and
* compat_filter_fn will be ignored. Otherwise the channel will be requested
* using dma_request_channel with compat_filter_fn as the filter function.
struct snd_dmaengine_pcm_config {
int (*prepare_slave_config)(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct dma_slave_config *slave_config);
struct dma_chan *(*compat_request_channel)(
struct snd_soc_pcm_runtime *rtd,
struct snd_pcm_substream *substream);
int (*process)(struct snd_pcm_substream *substream,
int channel, unsigned long hwoff,
void *buf, unsigned long bytes);
dma_filter_fn compat_filter_fn;
struct device *dma_dev;
const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
const struct snd_pcm_hardware *pcm_hardware;
unsigned int prealloc_buffer_size;
int snd_dmaengine_pcm_register(struct device *dev,
const struct snd_dmaengine_pcm_config *config,
unsigned int flags);
void snd_dmaengine_pcm_unregister(struct device *dev);
int devm_snd_dmaengine_pcm_register(struct device *dev,
const struct snd_dmaengine_pcm_config *config,
unsigned int flags);
int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct dma_slave_config *slave_config);
#define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
struct dmaengine_pcm {
struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
const struct snd_dmaengine_pcm_config *config;
struct snd_soc_component component;
unsigned int flags;
static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
return container_of(p, struct dmaengine_pcm, component);