diff --git a/common/jack/control.h b/common/jack/control.h
index 01c24ff0..d6d55b04 100644
--- a/common/jack/control.h
+++ b/common/jack/control.h
@@ -311,7 +311,6 @@ union jackctl_parameter_value
 jackctl_parameter_get_default_value(
 	jackctl_parameter_t * parameter);
     
-
 bool
 jackctl_parameter_has_range_constraint(
 	jackctl_parameter_t * parameter_ptr);
@@ -329,6 +328,11 @@ jackctl_parameter_get_enum_constraint_value(
 	jackctl_parameter_t * parameter_ptr,
 	uint32_t index);
 
+const char *
+jackctl_parameter_get_enum_constraint_description(
+	jackctl_parameter_t * parameter_ptr,
+	uint32_t index);
+
 void
 jackctl_parameter_get_range_constraint(
 	jackctl_parameter_t * parameter_ptr,