From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: Direct use of the DMA buffer?
Date: Mon, 20 Feb 2012 09:11:03 +0100
Message-ID: <4F420017.70508@ladisch.de>
References: <4F4181AF.1060303@ivitera.com>
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To: Pavel Hofman <pavel.hofman@ivitera.com>
Cc: ALSA development <alsa-devel@alsa-project.org>
List-Id: alsa-devel@alsa-project.org

Pavel Hofman wrote:
> Please excuse my ignorance, but is it possible for an application to
> directly use/output to the DMA buffer allocated by the kernel in
> hw_params?

Set one of the SND_PCM_ACCESS_MMAP_* access types and then use
snd_pcm_mmap_begin/commit.


Regards,
Clemens