diff --git a/reactos/include/ddk/portcls.h b/reactos/include/ddk/portcls.h
index 1a0f6d95d16..1c88b2401b8 100644
--- a/reactos/include/ddk/portcls.h
+++ b/reactos/include/ddk/portcls.h
@@ -2347,6 +2347,10 @@ PcRegisterAdapterPowerManagement(
   IN PUNKNOWN pUnknown,
   IN PVOID pvContext1);
 
+PORTCLASSAPI NTSTATUS NTAPI
+PcUnregisterAdapterPowerManagement(
+  IN PDEVICE_OBJECT DeviceObject);
+
 PORTCLASSAPI NTSTATUS NTAPI
 PcRequestNewPowerState(
   IN PDEVICE_OBJECT pDeviceObject,