[RFC PATCH 00/11] Introduce writeback connectors

[Daniel Vetter]

On Fri, Oct 14, 2016 at 2:39 PM, Brian Starkey <brian.starkey at arm.com> wrote:
>> - Besides the above property, writeback hardware can have provisions
>> for scaling, color space conversion and rotation. This would mean that
>> we'd eventually add more writeback specific props/params in
>> drm_connector/drm_connector_state. Would we be okay adding more such
>> props for connectors?
>
>
> I've wondered the same thing about bloating non-writeback connectors
> with writeback-specific stuff. If it does become significant, maybe
> we should subclass drm_connector and add a drm_writeback_state pointer
> to drm_connector_state.

No pionters needed, just embedded drm_connector_state into
drm_writeback_connector_state as the "base" member. Then we can
provide ready-made atomic_set/get_property functions for the aditional
writeback functionality.

But tbh I'd only start doing that once we have a few more. It's purely
an implementation change, with no effect on userspace. And if you go
with my drm_writeback_connector_init idea, it won't even be an issue
for drivers.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch