diff --git a/libnm-util/nm-setting-vpn.c b/libnm-util/nm-setting-vpn.c
index 8fbfbc22ae..c04b974160 100644
--- a/libnm-util/nm-setting-vpn.c
+++ b/libnm-util/nm-setting-vpn.c
@@ -144,6 +144,7 @@ nm_setting_vpn_new (void)
 
 /**
  * nm_setting_vpn_get_service_type:
+ * @setting: the #NMSettingVPN
  *
  * Returns the service name of the VPN, which identifies the specific VPN
  * plugin that should be used to connect to this VPN.