diff --git a/src/ipa/libipa/agc_mean_luminance.h b/src/ipa/libipa/agc_mean_luminance.h
index 3378ec7faa..e7e2d8ad0d 100644
--- a/src/ipa/libipa/agc_mean_luminance.h
+++ b/src/ipa/libipa/agc_mean_luminance.h
@@ -78,7 +78,7 @@ public:
 		return exposureModeHelpers_;
 	}
 
-	ControlInfoMap::Map controls()
+	const ControlInfoMap::Map &controls() const
 	{
 		return controls_;
 	}