drm/amd/display: Do not send training pattern if VS Different
authorSung Lee <sung.lee@amd.com>
Fri, 3 Jan 2020 19:03:52 +0000 (14:03 -0500)
committerAlex Deucher <alexander.deucher@amd.com>
Wed, 22 Jan 2020 21:55:27 +0000 (16:55 -0500)
commit5f46f34886b7c68f326b3e44b39fe77b47b29fb4
tree5c631a0be4b953f9f27c4fe780572a809d26477b
parent42c66a8b3aa6d2effb7adce81de808a4a58d9dc9
drm/amd/display: Do not send training pattern if VS Different

[Why]
The DP 1.4a Spec requires that training pattern only under certain
specific conditions. Currently driver will re-send
training pattern every time voltage swing value changes,
but that should not be the case.

[How]
Do not re-send training pattern every time VS values
are different. Only send it on the first iteration.

Signed-off-by: Sung Lee <sung.lee@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Abdoulaye Berthe <Abdoulaye.Berthe@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c