diff options
Diffstat (limited to 'include/sound/dmaengine_pcm.h')
| -rw-r--r-- | include/sound/dmaengine_pcm.h | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h new file mode 100644 index 000000000..2c4cfaa13 --- /dev/null +++ b/include/sound/dmaengine_pcm.h @@ -0,0 +1,163 @@ +/* SPDX-License-Identifier: GPL-2.0+ + * + * Copyright (C) 2012, Analog Devices Inc. + * Author: Lars-Peter Clausen <lars@metafoo.de> + */ + +#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); + +/* + * 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. + */ +#define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0) + +/** + * 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 + */ +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 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. + * @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" + +#endif |