LXR linux/include/sound/dmaengine

   1/* SPDX-License-Identifier: GPL-2.0+
   2 *
   3 *  Copyright (C) 2012, Analog Devices Inc.
   4 *      Author: Lars-Peter Clausen <lars@metafoo.de>
   5 */
   6
   7#ifndef __SOUND_DMAENGINE_PCM_H__
   8#define __SOUND_DMAENGINE_PCM_H__
   9
  10#include <sound/pcm.h>
  11#include <sound/soc.h>
  12#include <linux/dmaengine.h>
  13
  14/**
  15 * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
  16 *   substream
  17 * @substream: PCM substream
  18 */
  19static inline enum dma_transfer_direction
  20snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
  21{
  22        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  23                return DMA_MEM_TO_DEV;
  24        else
  25                return DMA_DEV_TO_MEM;
  26}
  27
  28int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
  29        const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
  30int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
  31snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
  32snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
  33
  34int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
  35        struct dma_chan *chan);
  36int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
  37
  38int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
  39        dma_filter_fn filter_fn, void *filter_data);
  40int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
  41
  42struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
  43        void *filter_data);
  44struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
  45
  46/*
  47 * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
  48 * If this flag is set the dmaengine driver won't put any restriction on
  49 * the supported sample formats and set the DMA transfer size to undefined.
  50 * The DAI driver is responsible to disable any unsupported formats in it's
  51 * configuration and catch corner cases that are not already handled in
  52 * the ALSA core.
  53 */
  54#define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)
  55
  56/**
  57 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
  58 * @addr: Address of the DAI data source or destination register.
  59 * @addr_width: Width of the DAI data source or destination register.
  60 * @maxburst: Maximum number of words(note: words, as in units of the
  61 * src_addr_width member, not bytes) that can be send to or received from the
  62 * DAI in one burst.
  63 * @slave_id: Slave requester id for the DMA channel.
  64 * @filter_data: Custom DMA channel filter data, this will usually be used when
  65 * requesting the DMA channel.
  66 * @chan_name: Custom channel name to use when requesting DMA channel.
  67 * @fifo_size: FIFO size of the DAI controller in bytes
  68 * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
  69 */
  70struct snd_dmaengine_dai_dma_data {
  71        dma_addr_t addr;
  72        enum dma_slave_buswidth addr_width;
  73        u32 maxburst;
  74        unsigned int slave_id;
  75        void *filter_data;
  76        const char *chan_name;
  77        unsigned int fifo_size;
  78        unsigned int flags;
  79};
  80
  81void snd_dmaengine_pcm_set_config_from_dai_data(
  82        const struct snd_pcm_substream *substream,
  83        const struct snd_dmaengine_dai_dma_data *dma_data,
  84        struct dma_slave_config *config);
  85
  86
  87/*
  88 * Try to request the DMA channel using compat_request_channel or
  89 * compat_filter_fn if it couldn't be requested through devicetree.
  90 */
  91#define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
  92/*
  93 * Don't try to request the DMA channels through devicetree. This flag only
  94 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
  95 */
  96#define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
  97/*
  98 * The PCM is half duplex and the DMA channel is shared between capture and
  99 * playback.
 100 */
 101#define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
 102
 103/**
 104 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
 105 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
 106 *   PCM substream. Will be called from the PCM drivers hwparams callback.
 107 * @compat_request_channel: Callback to request a DMA channel for platforms
 108 *   which do not use devicetree.
 109 * @process: Callback used to apply processing on samples transferred from/to
 110 *   user space.
 111 * @compat_filter_fn: Will be used as the filter function when requesting a
 112 *  channel for platforms which do not use devicetree. The filter parameter
 113 *  will be the DAI's DMA data.
 114 * @dma_dev: If set, request DMA channel on this device rather than the DAI
 115 *  device.
 116 * @chan_names: If set, these custom DMA channel names will be requested at
 117 *  registration time.
 118 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
 119 * @prealloc_buffer_size: Size of the preallocated audio buffer.
 120 *
 121 * Note: If both compat_request_channel and compat_filter_fn are set
 122 * compat_request_channel will be used to request the channel and
 123 * compat_filter_fn will be ignored. Otherwise the channel will be requested
 124 * using dma_request_channel with compat_filter_fn as the filter function.
 125 */
 126struct snd_dmaengine_pcm_config {
 127        int (*prepare_slave_config)(struct snd_pcm_substream *substream,
 128                        struct snd_pcm_hw_params *params,
 129                        struct dma_slave_config *slave_config);
 130        struct dma_chan *(*compat_request_channel)(
 131                        struct snd_soc_pcm_runtime *rtd,
 132                        struct snd_pcm_substream *substream);
 133        int (*process)(struct snd_pcm_substream *substream,
 134                       int channel, unsigned long hwoff,
 135                       void *buf, unsigned long bytes);
 136        dma_filter_fn compat_filter_fn;
 137        struct device *dma_dev;
 138        const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
 139
 140        const struct snd_pcm_hardware *pcm_hardware;
 141        unsigned int prealloc_buffer_size;
 142};
 143
 144int snd_dmaengine_pcm_register(struct device *dev,
 145        const struct snd_dmaengine_pcm_config *config,
 146        unsigned int flags);
 147void snd_dmaengine_pcm_unregister(struct device *dev);
 148
 149int devm_snd_dmaengine_pcm_register(struct device *dev,
 150        const struct snd_dmaengine_pcm_config *config,
 151        unsigned int flags);
 152
 153int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
 154        struct snd_pcm_hw_params *params,
 155        struct dma_slave_config *slave_config);
 156
 157#define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
 158
 159#endif
 160