From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: sw parameter boundary
Date: Wed, 25 Jun 2008 17:45:45 +0200
Message-ID: <s5h3an18qmu.wl%tiwai@suse.de>
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To: Norbert van Bolhuis <nvbolhuis@aimvalley.nl>
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At Wed, 25 Jun 2008 10:44:19 +0200,
Norbert van Bolhuis wrote:
> 
> 
> is the boundary sw parameter still used ?

Yes.

> where is it for ?

It defines the wrap point to the position 0.

> in the PCM kernel core (e.g. snd_pcm_playback_avail) it clearly serves
> as a pointers wrap point, but which one ?

It's for the absolute position handled internally.  This isn't
exported outside, so you don't care much about it, normally.

> The one at the end of the DMA buffer or the one at the end of a process
> (virtual) address range (4 GB) ?

No.


Takashi