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From: Luigi Rizzo <luigi@labinfo.iet.unipi.it>
Message-Id: <199708180241.EAA09720@labinfo.iet.unipi.it>
Subject: Re: Problem with my Wincast, fxtv
To: hasty@rah.star-gate.com (Amancio Hasty)
Date: Mon, 18 Aug 1997 04:41:33 +0200 (MET DST)
Cc: msmith@atrad.adelaide.edu.au, terry@lambert.org, mestery@winternet.com,
        freebsd-multimedia@FreeBSD.ORG, current@FreeBSD.ORG
In-Reply-To: <199708180201.TAA02325@rah.star-gate.com> from "Amancio Hasty" at Aug 17, 97 07:01:36 pm
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> >Ah, the light dawns.  How about the next isa_dma* function Luigi has
> >requested?  Is the sanity checking in general a major problem from your
> >point of view?
> 
> My right eye begings to nervously twitch ... Just joking .
> 
> I have no idea what Luigi wants to do next in the way of dma interface
> so  him and I will  have to "sit" down and iron out the functionality . 
> I will let Luigi post the outcome of our discussion . 

There is not much to discuss, basically I have proposed a new
function, isa_dmastop(chan), which allows me to stop a DMA transfer.
This _might_ be needed to implement functions such as PAUSE in a
clean way (not sure the function is really necessary, since one
can ni principle disable the DMA engine on the sound card and then
do things as if the transfer had finished. But since I am not sure
that all sound cards support disabling the DMA engine before a
transfer is complete, I prefer to have an alternative way as well.

The code bloat is minimum and the reason why I want it to be in isa.c
rather than in the sound driver is precisely what Steve Passe said,
avoid subsystem fiddle with the hardware in uncontrolled ways.

	Cheers
	Luigi