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Date: Mon, 2 Mar 2015 16:11:22 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Pawel Moll <pawel.moll@arm.com>
Cc: Arun Ramamurthy <arun.ramamurthy@broadcom.com>,
        Rob Herring <robh+dt@kernel.org>, Mark Rutland <Mark.Rutland@arm.com>,
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Subject: Re: [PATCH] video: ARM CLCD: Added support for FBIOPAN_DISPLAY and
 virtual y resolution
Message-ID: <20150302161122.GP8656@n2100.arm.linux.org.uk>
References: <1424898082-1522-1-git-send-email-arun.ramamurthy@broadcom.com>
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 <1425312509.3092.7.camel@arm.com>
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On Mon, Mar 02, 2015 at 04:08:29PM +0000, Pawel Moll wrote:
> I'm not sure about this... The word "virtual" never works well with
> device tree nodes defined as "hardware description".
> 
> I understand what you're doing, but adding this property to the display
> controller's node doesn't sound right. How does this describe hardware?
> If anywhere, it's more like a job for the panel node?

A better description (and implementation) would be to describe the size
of the RAM available for video purposes.  The driver can then use the
requested virtual X resolution to limit (and/or compute) the virtual Y
resolution to allow Y panning/wrapping of the display.

This would match some hardware where the video RAM is indeed a separate
physical set of RAM (such as the IM-PD/1).

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