imx21: define and use MX21_IO_ADDRESS

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Holger Schurig <hs4233@mail.mn-solutions.de>
Cc: Rabin Vincent <rabin@rab.in>
Cc: Agustín Ferrín Pozuelo <gatoguan-os@yahoo.com>
diff --git a/arch/arm/plat-mxc/include/mach/mx21.h b/arch/arm/plat-mxc/include/mach/mx21.h
index bb297d8..5b9f062 100644
--- a/arch/arm/plat-mxc/include/mach/mx21.h
+++ b/arch/arm/plat-mxc/include/mach/mx21.h
@@ -92,6 +92,11 @@
 
 #define MX21_IRAM_BASE_ADDR		0xffffe800	/* internal ram */
 
+#define MX21_IO_ADDRESS(x) (						\
+	IMX_IO_ADDRESS(x, MX21_AIPI) ?:					\
+	IMX_IO_ADDRESS(x, MX21_SAHB1) ?:				\
+	IMX_IO_ADDRESS(x, MX21_X_MEMC))
+
 /* fixed interrupt numbers */
 #define MX21_INT_CSPI3		6
 #define MX21_INT_GPIO		8