drm/amd/display: change hw sequence

[Why]
t9 delay func is called twice after setting power off, the unexpected
action results in a doubling of the added 140ms t9 delay

[How]
If the backlight has been turned off, does not turn it off again

Signed-off-by: Sherry <Yao.Wang1@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@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 9f56887..90c85b3 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
@@ -939,12 +939,15 @@ void dce110_edp_backlight_control(
                return;
        }
 
-       if (enable && link->panel_cntl &&
-               link->panel_cntl->funcs->is_panel_backlight_on(link->panel_cntl)) {
-               DC_LOG_HW_RESUME_S3(
-                               "%s: panel already powered up. Do nothing.\n",
+       if (link->panel_cntl) {
+               bool is_backlight_on = link->panel_cntl->funcs->is_panel_backlight_on(link->panel_cntl);
+
+               if ((enable && is_backlight_on) || (!enable && !is_backlight_on)) {
+                       DC_LOG_HW_RESUME_S3(
+                               "%s: panel already powered up/off. Do nothing.\n",
                                __func__);
-               return;
+                       return;
+               }
        }
 
        /* Send VBIOS command to control eDP panel backlight */