From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Daniel Berlin <dan@cgsoftware.com>
Cc: <linuxppc-dev@lists.linuxppc.org>,
	"Kevin B. Hendricks" <khendricks@ivey.uwo.ca>
Subject: Re: DFP support for kernel radeonfb.c added
Date: Wed, 14 Nov 2001 22:24:15 +0100
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>No, I mean using i2c to grab it.

I think OF uses the Radeon "GPIO" registers to probe the panel type based
on a wired panel ID and a table of EDIDs in the driver. At least, it did
it that way on mach64. I dumped a disassembly of the Rage M3 (r128 base)
MacOS 9 driver of my Pismo and started tracing it, it seem to play with
GPIOs as well. I didn't yet figure out the exact algorithm though.

Ben.


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