linux/include/sound/dmaengine_pcm.h
Lars-Peter Clausen acde50a7bf ASoC: dmaengine_pcm: Make FLAG_NO_RESIDUE internal
Whether residue can be reported or not is not a property of the audio
controller but of the DMA controller. The FLAG_NO_RESIDUE was initially
added when the DMAengine framework had no support for describing the residue
reporting capabilities of the controller. Support for this was added quite a
while ago and recently the DMAengine framework started to complain if a
driver does not describe its capabilities and a lot of patches have been
merged that add support for this where it was missing. So it should be safe
to assume that driver on actively used platforms properly implement the DMA
capabilities API.

This patch makes the FLAG_NO_RESIDUE internal and no longer allows audio
controller drivers to manually set the flag. If a DMA driver against
expectations does not support reporting its capabilities for now the generic
DMAengine PCM driver will now emit a warning and simply assume that residue
reporting is not supported. In the future this might be changed to aborting
with an error.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-04-27 19:26:07 +01:00

153 lines
5.7 KiB
C

/*
* Copyright (C) 2012, Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* 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; either version 2 of the License, or (at your
* option) any later version.
*
* 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#ifndef __SOUND_DMAENGINE_PCM_H__
#define __SOUND_DMAENGINE_PCM_H__
#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;
else
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);
/**
* 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
*/
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;
};
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);
/*
* Try to request the DMA channel using compat_request_channel or
* compat_filter_fn if it couldn't be requested through devicetree.
*/
#define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
/*
* 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.
*/
#define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
/*
* The PCM is half duplex and the DMA channel is shared between capture and
* playback.
*/
#define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
/*
* The PCM streams have custom channel names specified.
*/
#define SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME BIT(4)
/**
* 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.
* @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);
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);
#endif