diff --git a/arch/arm/mach-omap2/board-omap3touchbook.c b/arch/arm/mach-omap2/board-omap3touchbook.c
index 9ab18fd..09197a5 100644
--- a/arch/arm/mach-omap2/board-omap3touchbook.c
+++ b/arch/arm/mach-omap2/board-omap3touchbook.c
@@ -62,7 +62,7 @@
 #define TB_BL_PWM_TIMER		9
 #define TB_KILL_POWER_GPIO	168
 
-unsigned long touchbook_revision;
+static unsigned long touchbook_revision;
 
 static struct mtd_partition omap3touchbook_nand_partitions[] = {
 	/* All the partition sizes are listed in terms of NAND block size */