diff --git a/src/ipa/raspberrypi/controller/rpi/lux.hpp b/src/ipa/raspberrypi/controller/rpi/lux.hpp
index caa018da..04b82c4d 100644
--- a/src/ipa/raspberrypi/controller/rpi/lux.hpp
+++ b/src/ipa/raspberrypi/controller/rpi/lux.hpp
@@ -35,7 +35,7 @@ private:
 	double reference_Y_; // out of 65536
 	double reference_lux_;
 	double current_aperture_;
-	LuxStatus status_;
+	LuxStatus status_ LIBCAMERA_TSA_GUARDED_BY(mutex_);
 	libcamera::Mutex mutex_;
 };