drm/amd/display: Added local_sink null check before access

[Why & How]
Need to check if local_sink is NULL before accessing.

Signed-off-by: Jake Wang <haonan.wang2@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@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/core/dc_link_hwss.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
index 6590f51..93e2823 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
@@ -167,7 +167,8 @@ bool edp_receiver_ready_T9(struct dc_link *link)
                } while (++tries < 50);
        }
 
-       if (link->local_sink->edid_caps.panel_patch.extra_delay_backlight_off > 0)
+       if (link->local_sink &&
+                       link->local_sink->edid_caps.panel_patch.extra_delay_backlight_off > 0)
                udelay(link->local_sink->edid_caps.panel_patch.extra_delay_backlight_off * 1000);
 
        return result;
@@ -201,7 +202,8 @@ bool edp_receiver_ready_T7(struct dc_link *link)
                } while (time_taken_in_ns < 50 * 1000000); //MAx T7 is 50ms
        }
 
-       if (link->local_sink->edid_caps.panel_patch.extra_t7_ms > 0)
+       if (link->local_sink &&
+                       link->local_sink->edid_caps.panel_patch.extra_t7_ms > 0)
                udelay(link->local_sink->edid_caps.panel_patch.extra_t7_ms * 1000);
 
        return result;