diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci2032.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci2032.c
index 2d325163c1692c181ffceeb4ceff9c11530e98e6..d7d22236778d1f115f8e6f5b1174e7b6bd60613b 100644
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci2032.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci2032.c
@@ -53,7 +53,7 @@ You should also find the complete GPL in the COPYING file accompanying this sour
 */
 
 #include "hwdrv_apci2032.h"
-unsigned int ui_InterruptData, ui_Type;
+static unsigned int ui_InterruptData, ui_Type;
 /*
 +----------------------------------------------------------------------------+
 | Function   Name   : int i_APCI2032_ConfigDigitalOutput                     |