From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Hofman <pavel.hofman@ivitera.com>
Subject: Re: Direct use of the DMA buffer?
Date: Mon, 20 Feb 2012 09:38:44 +0100
Message-ID: <4F420694.6040902@ivitera.com>
References: <4F4181AF.1060303@ivitera.com> <4F420017.70508@ladisch.de>
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To: Clemens Ladisch <clemens@ladisch.de>
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Dne 20.2.2012 09:11, Clemens Ladisch napsal(a):
> 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.
> 

Clemens, thanks a lot for the information. How does it work when the
alsa-lib chain contains plugins, such as plug, rate, etc.? I would
assume the application circumvents these.

Thanks a lot.

Pavel.