Re: [PATCH v2 1/7] drm: writeback: Refactor drm_writeback_connector structure
From: Louis Chauvet
Date: Tue Nov 04 2025 - 05:25:03 EST
Le 07/10/2025 à 07:45, Suraj Kandpal a écrit :
Some drivers cannot work with the current design where the connector
is embedded within the drm_writeback_connector such as Intel and
some drivers that can get it working end up adding a lot of checks
all around the code to check if it's a writeback conenctor or not,
this is due to the limitation of inheritance in C.
To solve this move the drm_writeback_connector within the
drm_connector and remove the drm_connector base which was in
drm_writeback_connector. Make this drm_writeback_connector
a union with hdmi connector to save memory and since a connector can
never be both writeback and hdmi it should serve us well.
Do all other required modifications that come with these changes
along with addition of new function which returns the drm_connector
when drm_writeback_connector is present.
Modify drivers using the drm_writeback_connector to
allow them to use this connector without breaking them.
The drivers modified here are amd, komeda, mali, vc4, vkms,
rcar_du, msm
Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
---
V1 -> V2: Use &connector->writeback, make commit message imperative (Dmitry)
---
[...]
drivers/gpu/drm/vkms/vkms_composer.c | 2 +-
drivers/gpu/drm/vkms/vkms_drv.h | 2 +-
drivers/gpu/drm/vkms/vkms_writeback.c | 13 ++--
For the VKMS part:
Reviewed-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>
Thanks,
Louis Chauvet
--
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com