'\" t
.\"     Title: snd_dmaengine_pcm_open_request_chan
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: January 2017
.\"    Manual: PCM API
.\"    Source: Kernel Hackers Manual 4.8.15
.\"  Language: English
.\"
.TH "SND_DMAENGINE_PCM_OP" "9" "January 2017" "Kernel Hackers Manual 4\&.8\&." "PCM API"
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.SH "NAME"
snd_dmaengine_pcm_open_request_chan \- Open a dmaengine based PCM substream and request channel
.SH "SYNOPSIS"
.HP \w'int\ snd_dmaengine_pcm_open_request_chan('u
.BI "int snd_dmaengine_pcm_open_request_chan(struct\ snd_pcm_substream\ *\ " "substream" ", dma_filter_fn\ " "filter_fn" ", void\ *\ " "filter_data" ");"
.SH "ARGUMENTS"
.PP
\fIsubstream\fR
.RS 4
PCM substream
.RE
.PP
\fIfilter_fn\fR
.RS 4
Filter function used to request the DMA channel
.RE
.PP
\fIfilter_data\fR
.RS 4
Data passed to the DMA filter function
.RE
.SH "DESCRIPTION"
.PP
Returns 0 on success, a negative error code otherwise\&.
.PP
This function will request a DMA channel using the passed filter function and data\&. The function should usually be called from the pcm open callback\&. Note that this function will use private_data field of the substream\*(Aqs runtime\&. So it is not available to your pcm driver implementation\&.
.SH "COPYRIGHT"
.br