drm/radeon/kms: Fix logic error in DP HPD handler

Only disable the pipe if the monitor is physically
disconnected.  The previous logic also disabled the
pipe if the link was trained.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=41248

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_connectors.c

@@ -68,11 +68,11 @@ void radeon_connector_hotplug(struct drm_connector *connector)
 	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
 		int saved_dpms = connector->dpms;
 
-		if (radeon_hpd_sense(rdev, radeon_connector->hpd.hpd) &&
-		    radeon_dp_needs_link_train(radeon_connector))
-			drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
-		else
+		/* Only turn off the display it it's physically disconnected */
+		if (!radeon_hpd_sense(rdev, radeon_connector->hpd.hpd))
 			drm_helper_connector_dpms(connector, DRM_MODE_DPMS_OFF);
+		else if (radeon_dp_needs_link_train(radeon_connector))
+			drm_helper_connector_dpms(connector, DRM_MODE_DPMS_ON);
 		connector->dpms = saved_dpms;
 	}
 }