drm/radeon: don't do mst probing if MST isn't enabled.

This causes an oops as we haven't initialised the mst
layer.

Reported-by: Dave Jones <<davej@codemonkey.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index 1017338..2b98ed3 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -666,6 +666,9 @@ radeon_dp_mst_probe(struct radeon_connector *radeon_connector)
        int ret;
        u8 msg[1];
 
+       if (!radeon_mst)
+               return 0;
+
        if (dig_connector->dpcd[DP_DPCD_REV] < 0x12)
                return 0;