On Sat, May 09, 2026 at 09:00:14PM +0200, Jernej Skrabec wrote: > From: Jernej Skrabec <[email protected]> > > As it turns out, current H616 DE33 binding was written based on > incomplete understanding of DE33 design. Namely, planes are shared > resource and not tied to specific mixer, which was the case for previous > generations of Display Engine (DE3 and earlier). > > This means that current DE33 binding doesn't properly reflect HW and > using it would mean that second mixer (used for second display output) > can't be supported. > > Remove layer register space, which will be represented with additional > node, and replace it with phandle, which will point to that new, shared > node. That way, all mixers can share same layers. > > There is no user of this binding yet, so changes can be made safely, > without breaking any backward compatibility.
There is user. git grep gives me: drivers/gpu/drm/sun4i/sun8i_mixer.c which means this is a released ABI. As I understood, the old code was working fine but just did not support all use cases. Why this cannot be kept backwards compatible? Best regards, Krzysztof
