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.\"     Title: struct snd_dmaengine_pcm_config
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: PCM API
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "STRUCT SND_DMAENGINE" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "PCM API"
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.SH "NAME"
struct_snd_dmaengine_pcm_config \- Configuration data for dmaengine based PCM
.SH "SYNOPSIS"
.sp
.nf
struct snd_dmaengine_pcm_config {
  int (* prepare_slave_config) (struct snd_pcm_substream *substream,struct snd_pcm_hw_params *params,struct dma_slave_config *slave_config);
  struct dma_chan *(* compat_request_channel) (struct snd_soc_pcm_runtime *rtd,struct snd_pcm_substream *substream);
  dma_filter_fn compat_filter_fn;
  struct device * dma_dev;
  const char * chan_names[SNDRV_PCM_STREAM_LAST + 1];
  const struct snd_pcm_hardware * pcm_hardware;
  unsigned int prealloc_buffer_size;
};  
.fi
.SH "MEMBERS"
.PP
prepare_slave_config
.RS 4
Callback used to fill in the DMA slave_config for a PCM substream\&. Will be called from the PCM drivers hwparams callback\&.
.RE
.PP
compat_request_channel
.RS 4
Callback to request a DMA channel for platforms which do not use devicetree\&.
.RE
.PP
compat_filter_fn
.RS 4
Will be used as the filter function when requesting a channel for platforms which do not use devicetree\&. The filter parameter will be the DAI\*(Aqs DMA data\&.
.RE
.PP
dma_dev
.RS 4
If set, request DMA channel on this device rather than the DAI device\&.
.RE
.PP
chan_names[SNDRV_PCM_STREAM_LAST + 1]
.RS 4
If set, these custom DMA channel names will be requested at registration time\&.
.RE
.PP
pcm_hardware
.RS 4
snd_pcm_hardware struct to be used for the PCM\&.
.RE
.PP
prealloc_buffer_size
.RS 4
Size of the preallocated audio buffer\&.
.RE
.SH "NOTE"
.PP
If both compat_request_channel and compat_filter_fn are set compat_request_channel will be used to request the channel and compat_filter_fn will be ignored\&. Otherwise the channel will be requested using dma_request_channel with compat_filter_fn as the filter function\&.
.SH "COPYRIGHT"
.br