1 /* 2 * Copyright (C) 2012, Analog Devices Inc. 3 * Author: Lars-Peter Clausen <lars@metafoo.de> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License as published by the 7 * Free Software Foundation; either version 2 of the License, or (at your 8 * option) any later version. 9 * 10 * You should have received a copy of the GNU General Public License along 11 * with this program; if not, write to the Free Software Foundation, Inc., 12 * 675 Mass Ave, Cambridge, MA 02139, USA. 13 * 14 */ 15 #ifndef __SOUND_DMAENGINE_PCM_H__ 16 #define __SOUND_DMAENGINE_PCM_H__ 17 18 #include <sound/pcm.h> 19 #include <sound/soc.h> 20 #include <linux/dmaengine.h> 21 22 /** 23 * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM 24 * substream 25 * @substream: PCM substream 26 */ 27 static inline enum dma_transfer_direction 28 snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream) 29 { 30 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 31 return DMA_MEM_TO_DEV; 32 else 33 return DMA_DEV_TO_MEM; 34 } 35 36 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream, 37 const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config); 38 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd); 39 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream); 40 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream); 41 42 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, 43 struct dma_chan *chan); 44 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream); 45 46 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream, 47 dma_filter_fn filter_fn, void *filter_data); 48 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream); 49 50 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn, 51 void *filter_data); 52 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream); 53 54 /* 55 * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word. 56 * If this flag is set the dmaengine driver won't put any restriction on 57 * the supported sample formats and set the DMA transfer size to undefined. 58 * The DAI driver is responsible to disable any unsupported formats in it's 59 * configuration and catch corner cases that are not already handled in 60 * the ALSA core. 61 */ 62 #define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0) 63 64 /** 65 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data 66 * @addr: Address of the DAI data source or destination register. 67 * @addr_width: Width of the DAI data source or destination register. 68 * @maxburst: Maximum number of words(note: words, as in units of the 69 * src_addr_width member, not bytes) that can be send to or received from the 70 * DAI in one burst. 71 * @slave_id: Slave requester id for the DMA channel. 72 * @filter_data: Custom DMA channel filter data, this will usually be used when 73 * requesting the DMA channel. 74 * @fifo_size: FIFO size of the DAI controller in bytes 75 * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now 76 */ 77 struct snd_dmaengine_dai_dma_data { 78 dma_addr_t addr; 79 enum dma_slave_buswidth addr_width; 80 u32 maxburst; 81 unsigned int slave_id; 82 void *filter_data; 83 unsigned int fifo_size; 84 unsigned int flags; 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 93 /* 94 * Try to request the DMA channel using compat_request_channel or 95 * compat_filter_fn if it couldn't be requested through devicetree. 96 */ 97 #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0) 98 /* 99 * Don't try to request the DMA channels through devicetree. This flag only 100 * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well. 101 */ 102 #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1) 103 /* 104 * The PCM is half duplex and the DMA channel is shared between capture and 105 * playback. 106 */ 107 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3) 108 109 /** 110 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM 111 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a 112 * PCM substream. Will be called from the PCM drivers hwparams callback. 113 * @compat_request_channel: Callback to request a DMA channel for platforms 114 * which do not use devicetree. 115 * @compat_filter_fn: Will be used as the filter function when requesting a 116 * channel for platforms which do not use devicetree. The filter parameter 117 * will be the DAI's DMA data. 118 * @dma_dev: If set, request DMA channel on this device rather than the DAI 119 * device. 120 * @chan_names: If set, these custom DMA channel names will be requested at 121 * registration time. 122 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM. 123 * @prealloc_buffer_size: Size of the preallocated audio buffer. 124 * 125 * Note: If both compat_request_channel and compat_filter_fn are set 126 * compat_request_channel will be used to request the channel and 127 * compat_filter_fn will be ignored. Otherwise the channel will be requested 128 * using dma_request_channel with compat_filter_fn as the filter function. 129 */ 130 struct snd_dmaengine_pcm_config { 131 int (*prepare_slave_config)(struct snd_pcm_substream *substream, 132 struct snd_pcm_hw_params *params, 133 struct dma_slave_config *slave_config); 134 struct dma_chan *(*compat_request_channel)( 135 struct snd_soc_pcm_runtime *rtd, 136 struct snd_pcm_substream *substream); 137 dma_filter_fn compat_filter_fn; 138 struct device *dma_dev; 139 const char *chan_names[SNDRV_PCM_STREAM_LAST + 1]; 140 141 const struct snd_pcm_hardware *pcm_hardware; 142 unsigned int prealloc_buffer_size; 143 }; 144 145 int snd_dmaengine_pcm_register(struct device *dev, 146 const struct snd_dmaengine_pcm_config *config, 147 unsigned int flags); 148 void snd_dmaengine_pcm_unregister(struct device *dev); 149 150 int devm_snd_dmaengine_pcm_register(struct device *dev, 151 const struct snd_dmaengine_pcm_config *config, 152 unsigned int flags); 153 154 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream, 155 struct snd_pcm_hw_params *params, 156 struct dma_slave_config *slave_config); 157 158 #endif 159