Best practice device tree design for display subsystems/DRM

[Russell King]

On Thu, Jul 04, 2013 at 10:58:17AM +0200, Sascha Hauer wrote:
> On Thu, Jul 04, 2013 at 09:40:52AM +0100, Russell King wrote:
> > Wrong.  Please read the example with the diagrams I gave.  Consider
> > what happens if you have two display devices connected to a single
> > output, one which fixes the allowable mode and one which _can_
> > reformat the selected mode.
> 
> What you describe here is a forced clone mode. This could be described
> in the devicetree so that a driver wouldn't start before all connected
> displays (links) are present, but this should be limited to the affected
> path, not to the whole componentized device.

Okay, to throw a recent argument back at you: so what in this scenario
if you have a driver for the fixed-mode device but not the other device?

It's exactly the same problem which you were describing to Sebastian
just a moment ago with drivers missing from the supernode approach -
you can't start if one of those "forced clone" drivers is missing.

-- 
Russell King