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Date: Fri, 17 May 2002 00:07:50 -0700
From: Mike Fedyk <mfedyk@matchmail.com>
To: Neil Conway <nconway.list@ukaea.org.uk>
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Subject: Re: [PATCH] 2.5.15 IDE 61
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On Wed, May 15, 2002 at 12:55:37PM +0100, Neil Conway wrote:
> You can (and must) safely "touch the cable" in between TCQ commands in
> the right circumstances.  You are therefore touching the cable while the
> hwgroup is busy, hence my suggestion that the flag we use to prevent
> touching the cable during DMA should be named something other than busy.
>

Ahh, but with TCQ the concept of busy changes.  The wire (simplified) is
only busy when the tags are being transfered, otherwise the cable is unused
unless the cable has been "locked" by one of the devices.