On Tue, Jul 17, 2018 at 02:25:22PM +0200, Paul Kocialkowski wrote:
> Blending order is set based on the z position of each DRM plane. The
> blending order register is currently cleared at each atomic DRM commit,
> with the intent that each committed plane will set the appropriate
> bits (based on its z-pos) when enabling the plane.
> 
> However, it sometimes happens that a particular plane is left unchanged
> by an atomic commit and thus will not be configured again. In that
> scenario, blending order is cleared and only the bits relevant for the
> planes affected by the commit are set. This leaves the planes that did
> not change without their blending order set in the register, leading
> to that plane not being displayed.
> 
> Instead of clearing the blending order register at every atomic commit,
> this change moves the register's initial clear at bind time and only
> clears the bits for a specific plane when disabling it or changing its
> zpos.
> 
> This way, planes that are left untouched by a DRM atomic commit are
> no longer disabled.
> 
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

Applied, thanks!
Maxime

-- 
Maxime Ripard, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com