2 * Copyright (C) 2012, Analog Devices Inc.
3 * Author: Lars-Peter Clausen <lars@metafoo.de>
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.
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.
15 #ifndef __SOUND_DMAENGINE_PCM_H__
16 #define __SOUND_DMAENGINE_PCM_H__
18 #include <sound/pcm.h>
19 #include <linux/dmaengine.h>
22 * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
24 * @substream: PCM substream
26 static inline enum dma_transfer_direction
27 snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
29 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
30 return DMA_MEM_TO_DEV;
32 return DMA_DEV_TO_MEM;
35 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
36 const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
37 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
38 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
39 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
41 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
42 struct dma_chan *chan);
43 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
45 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
46 dma_filter_fn filter_fn, void *filter_data);
47 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
49 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
52 * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
53 * @addr: Address of the DAI data source or destination register.
54 * @addr_width: Width of the DAI data source or destination register.
55 * @maxburst: Maximum number of words(note: words, as in units of the
56 * src_addr_width member, not bytes) that can be send to or received from the
58 * @slave_id: Slave requester id for the DMA channel.
59 * @filter_data: Custom DMA channel filter data, this will usually be used when
60 * requesting the DMA channel.
62 struct snd_dmaengine_dai_dma_data {
64 enum dma_slave_buswidth addr_width;
66 unsigned int slave_id;
70 void snd_dmaengine_pcm_set_config_from_dai_data(
71 const struct snd_pcm_substream *substream,
72 const struct snd_dmaengine_dai_dma_data *dma_data,
73 struct dma_slave_config *config);
76 * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
77 * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
78 * PCM substream. Will be called from the PCM drivers hwparams callback.
79 * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
80 * @prealloc_buffer_size: Size of the preallocated audio buffer.
82 struct snd_dmaengine_pcm_config {
83 int (*prepare_slave_config)(struct snd_pcm_substream *substream,
84 struct snd_pcm_hw_params *params,
85 struct dma_slave_config *slave_config);
87 const struct snd_pcm_hardware *pcm_hardware;
88 unsigned int prealloc_buffer_size;
91 int snd_dmaengine_pcm_register(struct device *dev,
92 const struct snd_dmaengine_pcm_config *config,
94 void snd_dmaengine_pcm_unregister(struct device *dev);
96 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
97 struct snd_pcm_hw_params *params,
98 struct dma_slave_config *slave_config);