diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index ab9de1b..2fcdc0b 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -281,7 +281,7 @@
 }
 
 /* set slsb states to initial state */
-void qdio_init_buf_states(struct qdio_irq *irq_ptr)
+static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
 {
 	struct qdio_q *q;
 	int i;