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 static inline enum dma_transfer_direction 20 snd_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 28 int 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); 30 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd); 31 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream); 32 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream); 33 34 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, 35 struct dma_chan *chan); 36 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream); 37 38 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream, 39 dma_filter_fn filter_fn, void *filter_data); 40 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream); 41 42 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn, 43 void *filter_data); 44 struct 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 */ 70 struct 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 81 void 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 */ 126 struct 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 }; 143 144 int snd_dmaengine_pcm_register(struct device *dev, 145 const struct snd_dmaengine_pcm_config *config, 146 unsigned int flags); 147 void snd_dmaengine_pcm_unregister(struct device *dev); 148 149 int devm_snd_dmaengine_pcm_register(struct device *dev, 150 const struct snd_dmaengine_pcm_config *config, 151 unsigned int flags); 152 153 int 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