drm/amd/display: Fix dim display on DCE11

Before programming the input gamma, check that we're not using the
identity correction.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
index 78bf4fa..52427ae 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
@@ -280,7 +280,9 @@ dce110_set_input_transfer_func(struct pipe_ctx *pipe_ctx,
        build_prescale_params(&prescale_params, plane_state);
        ipp->funcs->ipp_program_prescale(ipp, &prescale_params);
 
-       if (plane_state->gamma_correction && dce_use_lut(plane_state->format))
+       if (plane_state->gamma_correction &&
+                       !plane_state->gamma_correction->is_identity &&
+                       dce_use_lut(plane_state->format))
                ipp->funcs->ipp_program_input_lut(ipp, plane_state->gamma_correction);
 
        if (tf == NULL) {