include/sound/dmaengine_pcm.h

   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  *
  19  * Return: DMA transfer direction
  20  */
  21 static inline enum dma_transfer_direction
  22 snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
  23 {
  24         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  25                 return DMA_MEM_TO_DEV;
  26         else
  27                 return DMA_DEV_TO_MEM;
  28 }
  29
  30 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
  31         const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
  32 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
  33 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
  34 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
  35
  36 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
  37         struct dma_chan *chan);
  38 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
  39 int snd_dmaengine_pcm_sync_stop(struct snd_pcm_substream *substream);
  40
  41 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
  42         dma_filter_fn filter_fn, void *filter_data);
  43 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
  44
  45 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
  46         void *filter_data);
  47 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
  48
  49 /*
  50  * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
  51  * If this flag is set the dmaengine driver won't put any restriction on
  52  * the supported sample formats and set the DMA transfer size to undefined.
  53  * The DAI driver is responsible to disable any unsupported formats in it's
  54  * configuration and catch corner cases that are not already handled in
  55  * the ALSA core.
  56  */
  57 #define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)
  58
  59 /**
  60  * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
  61  * @addr: Address of the DAI data source or destination register.
  62  * @addr_width: Width of the DAI data source or destination register.
  63  * @maxburst: Maximum number of words(note: words, as in units of the
  64  * src_addr_width member, not bytes) that can be send to or received from the
  65  * DAI in one burst.
  66  * @filter_data: Custom DMA channel filter data, this will usually be used when
  67  * requesting the DMA channel.
  68  * @chan_name: Custom channel name to use when requesting DMA channel.
  69  * @fifo_size: FIFO size of the DAI controller in bytes
  70  * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
  71  * @peripheral_config: peripheral configuration for programming peripheral
  72  * for dmaengine transfer
  73  * @peripheral_size: peripheral configuration buffer size
  74  */
  75 struct snd_dmaengine_dai_dma_data {
  76         dma_addr_t addr;
  77         enum dma_slave_buswidth addr_width;
  78         u32 maxburst;
  79         void *filter_data;
  80         const char *chan_name;
  81         unsigned int fifo_size;
  82         unsigned int flags;
  83         void *peripheral_config;
  84         size_t peripheral_size;
  85 };
  86
  87 void snd_dmaengine_pcm_set_config_from_dai_data(
  88         const struct snd_pcm_substream *substream,
  89         const struct snd_dmaengine_dai_dma_data *dma_data,
  90         struct dma_slave_config *config);
  91
  92 int snd_dmaengine_pcm_refine_runtime_hwparams(
  93         struct snd_pcm_substream *substream,
  94         struct snd_dmaengine_dai_dma_data *dma_data,
  95         struct snd_pcm_hardware *hw,
  96         struct dma_chan *chan);
  97
  98 /*
  99  * Try to request the DMA channel using compat_request_channel or
 100  * compat_filter_fn if it couldn't be requested through devicetree.
 101  */
 102 #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
 103 /*
 104  * Don't try to request the DMA channels through devicetree. This flag only
 105  * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
 106  */
 107 #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
 108 /*
 109  * The PCM is half duplex and the DMA channel is shared between capture and
 110  * playback.
 111  */
 112 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
 113
 114 /**
 115  * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
 116  * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
 117  *   PCM substream. Will be called from the PCM drivers hwparams callback.
 118  * @compat_request_channel: Callback to request a DMA channel for platforms
 119  *   which do not use devicetree.
 120  * @process: Callback used to apply processing on samples transferred from/to
 121  *   user space.
 122  * @name: Component name. If null, dev_name will be used.
 123  * @compat_filter_fn: Will be used as the filter function when requesting a
 124  *  channel for platforms which do not use devicetree. The filter parameter
 125  *  will be the DAI's DMA data.
 126  * @dma_dev: If set, request DMA channel on this device rather than the DAI
 127  *  device.
 128  * @chan_names: If set, these custom DMA channel names will be requested at
 129  *  registration time.
 130  * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
 131  * @prealloc_buffer_size: Size of the preallocated audio buffer.
 132  *
 133  * Note: If both compat_request_channel and compat_filter_fn are set
 134  * compat_request_channel will be used to request the channel and
 135  * compat_filter_fn will be ignored. Otherwise the channel will be requested
 136  * using dma_request_channel with compat_filter_fn as the filter function.
 137  */
 138 struct snd_dmaengine_pcm_config {
 139         int (*prepare_slave_config)(struct snd_pcm_substream *substream,
 140                         struct snd_pcm_hw_params *params,
 141                         struct dma_slave_config *slave_config);
 142         struct dma_chan *(*compat_request_channel)(
 143                         struct snd_soc_pcm_runtime *rtd,
 144                         struct snd_pcm_substream *substream);
 145         int (*process)(struct snd_pcm_substream *substream,
 146                        int channel, unsigned long hwoff,
 147                        unsigned long bytes);
 148         const char *name;
 149         dma_filter_fn compat_filter_fn;
 150         struct device *dma_dev;
 151         const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];
 152
 153         const struct snd_pcm_hardware *pcm_hardware;
 154         unsigned int prealloc_buffer_size;
 155 };
 156
 157 int snd_dmaengine_pcm_register(struct device *dev,
 158         const struct snd_dmaengine_pcm_config *config,
 159         unsigned int flags);
 160 void snd_dmaengine_pcm_unregister(struct device *dev);
 161
 162 int devm_snd_dmaengine_pcm_register(struct device *dev,
 163         const struct snd_dmaengine_pcm_config *config,
 164         unsigned int flags);
 165
 166 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
 167         struct snd_pcm_hw_params *params,
 168         struct dma_slave_config *slave_config);
 169
 170 #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"
 171
 172 struct dmaengine_pcm {
 173         struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
 174         const struct snd_dmaengine_pcm_config *config;
 175         struct snd_soc_component component;
 176         unsigned int flags;
 177 };
 178
 179 static inline struct dmaengine_pcm *soc_component_to_pcm(struct snd_soc_component *p)
 180 {
 181         return container_of(p, struct dmaengine_pcm, component);
 182 }
 183 #endif