ui brightness: fix exposure scale factor (#26104)

selfdrive/ui/ui.cc

@@ -163,7 +163,8 @@ static void update_state(UIState *s) {
     scene.longitudinal_control = sm["carParams"].getCarParams().getOpenpilotLongitudinalControl();
   }
   if (sm.updated("wideRoadCameraState")) {
-    scene.light_sensor = 100.0f - sm["wideRoadCameraState"].getWideRoadCameraState().getExposureValPercent();
+    float scale = (sm["wideRoadCameraState"].getWideRoadCameraState().getSensor() == cereal::FrameData::ImageSensor::AR0321) ? 6.0f : 1.0f;
+    scene.light_sensor = std::max(100.0f - scale * sm["wideRoadCameraState"].getWideRoadCameraState().getExposureValPercent(), 0.0f);
   }
   scene.started = sm["deviceState"].getDeviceState().getStarted() && scene.ignition;
 }