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To: Luigi Rizzo <luigi@labinfo.iet.unipi.it>
cc: brianc@pobox.com (Brian Campbell), freebsd-multimedia@FreeBSD.ORG
Subject: Re: dma handling in the sound driver 
In-reply-to: Your message of "Sun, 20 Jul 1997 09:11:51 +0200."
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Date: Sun, 20 Jul 1997 10:43:45 -0700
From: Amancio Hasty <hasty@rah.star-gate.com>
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Hi Guys,

I understand Luigi's position given that I had to dig into the
code and understand it. Simplication of the dma code is a very
important step towards having having a stable sound driver and
for future support by others.

	Have fun,
	Amancio

>From The Desk Of Luigi Rizzo :
> > On Sat, Jul 19, 1997 at 04:37:50PM +0200, Luigi Rizzo wrote:
> > > I have planned to rewrite the dma buffer handling routines for
> > > the sound driver as follows.
> > 
> > Why?
> > 
> > Is the current mechanism insufficient?  I thought changes were only
> > requried for full-duplex operation.
> > 
> > There is a mechanism for setting the size and number of DMA buffers,
> > is there not?  Will this be removed, or the settings simply ignored?
> 
> the main problem I have is that I find the dma code quite complex to
> follow and understand (as all code which has been evolving for a long
> time and adapting to new boards etc.). The scheme I have described is,
> in my opinion, simpler and more effective with respect to latency.
> 
> Maybe it's just my problem but since I am doing the work I'll do it in
> the way I find more effective.
> 
> Plus I'll document it !
> 
> 	Cheers
> 	Luigi