drm/amd/display: fix gamma not being applied correctly

[why]
Gamma was always being set as identity on SDR monitor,
leading to no changes in gamma. This caused nightlight to
not apply correctly.

[how]
Added a default gamma structure to compare against
in the sdr case.

Signed-off-by: Murton Liu <murton.liu@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
index a59b89b..84cfe70 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c
@@ -1227,7 +1227,8 @@ static bool dcn10_set_input_transfer_func(struct pipe_ctx *pipe_ctx,
                tf = plane_state->in_transfer_func;
 
        if (plane_state->gamma_correction &&
-               !plane_state->gamma_correction->is_identity
+               !dpp_base->ctx->dc->debug.always_use_regamma
+               && !plane_state->gamma_correction->is_identity
                        && dce_use_lut(plane_state->format))
                dpp_base->funcs->dpp_program_input_lut(dpp_base, plane_state->gamma_correction);