]> git.ipfire.org Git - thirdparty/linux.git/commit
drm/atomic-helper: Re-order bridge chain pre-enable and post-disable
authorAradhya Bhatia <a-bhatia1@ti.com>
Thu, 5 Jun 2025 17:15:23 +0000 (22:45 +0530)
committerMaxime Ripard <mripard@kernel.org>
Fri, 6 Jun 2025 12:24:57 +0000 (14:24 +0200)
commitc9b1150a68d9362a0827609fc0dc1664c0d8bfe1
tree2adbf2254c393f9704c29f55f954d0af034ea614
parentd5bef6430c85ffa4c92e8723974e012695409a10
drm/atomic-helper: Re-order bridge chain pre-enable and post-disable

Move the bridge pre_enable call before crtc enable, and the bridge
post_disable call after the crtc disable.

The sequence of enable after this patch will look like:

bridge[n]_pre_enable
...
bridge[1]_pre_enable

crtc_enable
encoder_enable

bridge[1]_enable
...
bridge[n]_enable

And, the disable sequence for the display pipeline will look like:

bridge[n]_disable
...
bridge[1]_disable

encoder_disable
crtc_disable

bridge[1]_post_disable
...
bridge[n]_post_disable

The definition of bridge pre_enable hook says that,
"The display pipe (i.e. clocks and timing signals) feeding this bridge
will not yet be running when this callback is called".

Since CRTC is also a source feeding the bridge, it should not be enabled
before the bridges in the pipeline are pre_enabled. Fix that by
re-ordering the sequence of bridge pre_enable and bridge post_disable.

While at it, update the drm bridge API documentation as well.

Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@linux.dev>
Tested-by: Devarsh Thakkar <devarsht@ti.com>
Link: https://lore.kernel.org/r/20250605171524.27222-4-aradhya.bhatia@linux.dev
Signed-off-by: Maxime Ripard <mripard@kernel.org>
drivers/gpu/drm/drm_atomic_helper.c
include/drm/drm_bridge.h