mmc: omap_hsmmc: add DDR support

Add Dual data rate support for omap_hsmmc.
Signed-off-by: NBalaji T K <balajitk@ti.com>
Signed-off-by: NVenkatraman S <svenkatr@ti.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

drivers/mmc/host/omap_hsmmc.c

@@ -92,6 +92,7 @@
 #define MSBS			(1 << 5)
 #define BCE			(1 << 1)
 #define FOUR_BIT		(1 << 1)
+#define DDR			(1 << 19)
 #define DW8			(1 << 5)
 #define CC			0x1
 #define TC			0x02
@@ -523,6 +524,10 @@ static void omap_hsmmc_set_bus_width(struct omap_hsmmc_host *host)
 	u32 con;
 
 	con = OMAP_HSMMC_READ(host->base, CON);
+	if (ios->timing == MMC_TIMING_UHS_DDR50)
+		con |= DDR;	/* configure in DDR mode */
+	else
+		con &= ~DDR;
 	switch (ios->bus_width) {
 	case MMC_BUS_WIDTH_8:
 		OMAP_HSMMC_WRITE(host->base, CON, con | DW8);