ARM: mx5: check for error in ioremap

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-mx5/board-cpuimx51.c b/arch/arm/mach-mx5/board-cpuimx51.c
index 6ab002d..125a196 100644
--- a/arch/arm/mach-mx5/board-cpuimx51.c
+++ b/arch/arm/mach-mx5/board-cpuimx51.c
@@ -178,6 +178,8 @@
 	void __iomem *usbother_base;
 
 	usb_base = ioremap(MX51_OTG_BASE_ADDR, SZ_4K);
+	if (!usb_base)
+		return -ENOMEM;
 	usbother_base = usb_base + MX5_USBOTHER_REGS_OFFSET;
 
 	/* Set the PHY clock to 19.2MHz */
@@ -196,6 +198,8 @@
 	void __iomem *usbother_base;
 
 	usb_base = ioremap(MX51_OTG_BASE_ADDR, SZ_4K);
+	if (!usb_base)
+		return -ENOMEM;
 	usbother_base = usb_base + MX5_USBOTHER_REGS_OFFSET;
 
 	/* The clock for the USBH1 ULPI port will come externally from the PHY. */