diff --git a/phosphor-power-supply/test/mock.hpp b/phosphor-power-supply/test/mock.hpp
index d354c9f..a6a384b 100644
--- a/phosphor-power-supply/test/mock.hpp
+++ b/phosphor-power-supply/test/mock.hpp
@@ -54,6 +54,7 @@
 {
   public:
     MOCK_METHOD(int, read, (), (override));
+    MOCK_METHOD(void, write, (int value, std::bitset<32> flags), (override));
     MOCK_METHOD(std::string, getName, (), (const, override));
 };