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SubjectRe: [PATCH 03/19 v2] Staging: xgifb: Remove LCDA detection in xgifb_probe().
Hi,

On Mon, Jul 09, 2012 at 11:39:47AM -0700, Greg KH wrote:
> On Fri, Jul 06, 2012 at 12:40:38PM +0200, Miguel Gómez wrote:
> > The piece of code that checks for LCDA in xgifb_probe() just checks for some
> > register values but doesn't really do anything in response to them (the actions
> > that should be executed are commented).
> > As nothing is really being done, the code can be safely removed.
>
> Are you sure? Some devices (foolish ones that is) need registers read
> to work properly as that is part of their start-up logic. Yeah, it
> doesn't seem to make sense, but hardware designers usually have good
> reasons for doing this type of thing. Or at least they think they do :)

Those registers (CR 0x30..0x38) are scratch registers, so reading them
should have no side effects in the device side. I think it's safe to
delete that code.

A.
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