diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 804dbb2..9476c1c 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -495,8 +495,8 @@
 		}
 		uart->wk_mask = wk_mask;
 	} else {
-		uart->wk_en = 0;
-		uart->wk_st = 0;
+		uart->wk_en = NULL;
+		uart->wk_st = NULL;
 		uart->wk_mask = 0;
 		uart->padconf = 0;
 	}