[PATCH, RFC] displaymodes in devicetree

[Sascha Hauer]

On Wed, Jun 27, 2012 at 06:16:12AM -1000, Mitch Bradley wrote:
> On 6/27/2012 2:43 AM, Sascha Hauer wrote:
> >Hi All,
> >
> >I'd like to have a possibility to describe fixed display modes in the
> >devicetree. This topic has been discussed before here:
> >
> >https://lists.ozlabs.org/pipermail/linuxppc-dev/2010-February/080683.html
> >
> >The result at that time was that EDID data should be considered to use
> >as this is a format that already exists. I want to come back to this
> >topic since:
> >
> >- EDID data is a binary format and as such quite inconvenient to handle.
> >   There exist several tools to parse EDID data, but I'm not aware of any
> >   (open source) tool which can generate EDID data.
> >- EDID blobs are hard to modify and hard to review in patches.
> >- EDID is designed to describe multiple modes, but fixed displays
> >   usually only support a single fixed mode.
> >
> >There are several ways of describing the mode, for this patch I chose to
> >use the format (and naming) used by the Linux Framebuffer Layer as this
> >is the only description which does not allow for inconsistent modes. I
> >added the most common flags like [v|h]sync_active_high. Others can be
> >added, but these flags are pretty much agreed upon and won't be
> >superseeded with other flags. The mode from the devicetree can be
> >converted to the most common modes used in Linux, struct fb_videomode
> >and struct drm_display_mode.
> >
> >Comments welcome
> 
> 
> I like the general approach and the set of names.  The separators
> inside the names should be hyphen (-) not underscore (_), following
> the usual device tree convention.  The rationale for that convention
> is to follow natural-language usage, not the identifier constraints
> of programming languages based on algebraic expressions.

Good to hear that this is the convention for devicetree, I like
hyphens better aswell. Will change.

Sascha

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