diff --git a/it87spi.c b/it87spi.c
index 13b3aae..9e7a8ea 100644
--- a/it87spi.c
+++ b/it87spi.c
@@ -57,7 +57,7 @@
 	sio_write(port, 0x02, 0x02);
 }
 
-uint16_t probe_id_ite(uint16_t port)
+static uint16_t probe_id_ite(uint16_t port)
 {
 	uint16_t id;