Index: abi/include/abi/ipc/interfaces.h
===================================================================
--- abi/include/abi/ipc/interfaces.h	(revision a72f3b87bcdb8b8f14877d2ce9c68a09661f54c3)
+++ abi/include/abi/ipc/interfaces.h	(revision edc89bd8532222d0daa40cad5eaddcc88db69245)
@@ -206,5 +206,7 @@
 	    FOURCC_COMPACT('s', 's', 't', 'm') | IFACE_EXCHANGE_SERIALIZE,
 	INTERFACE_SYSTEM_CB =
-	    FOURCC_COMPACT('s', 's', 't', 'm') | IFACE_EXCHANGE_SERIALIZE | IFACE_MOD_CALLBACK
+	    FOURCC_COMPACT('s', 's', 't', 'm') | IFACE_EXCHANGE_SERIALIZE | IFACE_MOD_CALLBACK,
+	INTERFACE_HR =
+	    FOURCC_COMPACT('h', 'r', ' ', ' ') | IFACE_EXCHANGE_SERIALIZE
 } iface_t;