mmc: dw_mmc: support the DDR mode

Support the DDR mode at dw-mmc controller

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Tested-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/include/dwmmc.h b/include/dwmmc.h
index 14c7db8..b67f11b 100644
--- a/include/dwmmc.h
+++ b/include/dwmmc.h
@@ -123,6 +123,9 @@
 #define DWMCI_BMOD_IDMAC_FB	(1 << 1)
 #define DWMCI_BMOD_IDMAC_EN	(1 << 7)
 
+/* UHS register */
+#define DWMCI_DDR_MODE	(1 << 16)
+
 /* quirks */
 #define DWMCI_QUIRK_DISABLE_SMU		(1 << 0)