diff --git a/src/modem-manager/nm-modem-manager.c b/src/modem-manager/nm-modem-manager.c
index cb43c7b72..df71f3d08 100644
--- a/src/modem-manager/nm-modem-manager.c
+++ b/src/modem-manager/nm-modem-manager.c
@@ -48,26 +48,6 @@ nm_modem_manager_get (void)
 	return singleton;
 }
 
-gboolean
-nm_modem_manager_has_modem_for_iface (NMModemManager *manager,
-                                      const gchar *iface)
-{
-	NMModemManagerPrivate *priv = NM_MODEM_MANAGER_GET_PRIVATE (manager);
-	GList *iter;
-	g_assert (manager);
-	g_assert (NM_IS_MODEM_MANAGER(manager));
-	g_assert (iface);
-
-	for (iter = g_hash_table_get_values(priv->modems); iter != NULL; iter = iter->next) {
-		NMModem *modem = NM_MODEM (iter->data);
-		const char *modem_iface = nm_modem_get_iface (modem);
-
-		if (!g_strcmp0 (iface, modem_iface))
-			return TRUE;
-	}
-	return FALSE;
-}
-
 static gboolean
 get_modem_properties (DBusGConnection *connection,
 					  const char *path,
diff --git a/src/modem-manager/nm-modem-manager.h b/src/modem-manager/nm-modem-manager.h
index 7402f534d..19b991a38 100644
--- a/src/modem-manager/nm-modem-manager.h
+++ b/src/modem-manager/nm-modem-manager.h
@@ -30,7 +30,4 @@ GType nm_modem_manager_get_type (void);
 
 NMModemManager *nm_modem_manager_get (void);
 
-gboolean nm_modem_manager_has_modem_for_iface (NMModemManager *manager,
-                                               const gchar *iface);
-
 #endif /* NM_MODEM_MANAGER_H */
diff --git a/src/nm-manager.c b/src/nm-manager.c
index 66b50ea26..e27fb94e3 100644
--- a/src/nm-manager.c
+++ b/src/nm-manager.c
@@ -127,15 +127,13 @@ static const char *internal_activate_device (NMManager *manager,
                                              gboolean assumed,
                                              GError **error);
 
-static NMDevice *
-find_device_by_iface (NMManager *self, const gchar *iface);
+static NMDevice *find_device_by_iface (NMManager *self, const gchar *iface);
 
-static GSList *
-remove_one_device (NMManager *manager,
-                   GSList *list,
-                   NMDevice *device,
-                   gboolean quitting,
-                   gboolean force_unmanage);
+static GSList * remove_one_device (NMManager *manager,
+                                   GSList *list,
+                                   NMDevice *device,
+                                   gboolean quitting,
+                                   gboolean force_unmanage);
 
 static NMDevice *nm_manager_get_device_by_udi (NMManager *manager, const char *udi);
 
@@ -1214,7 +1212,7 @@ add_device (NMManager *self, NMDevice *device)
 	iface = nm_device_get_ip_iface (device);
 	g_assert (iface);
 
-	if (!NM_IS_MODEM (device) && nm_modem_manager_has_modem_for_iface (priv->modem_manager, iface)) {
+	if (!NM_IS_MODEM (device) && find_device_by_iface (self, iface)) {
 		g_object_unref (device);
 		return;
 	}