Re: [PATCH v2 1/7] drm: writeback: Refactor drm_writeback_connector structure

[Louis Chauvet <louis.chauvet@bootlin.com>]

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@intel.com>
> ---
> 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@bootlin.com>

Thanks,
Louis Chauvet

--
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com