mmc: refine DDR support

One flaw with DDR support is that MMC core does not inform the driver
which DDR mode it has selected.  This patch expands the ios->ddr flag
to do that.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/core/core.c

@@ -653,10 +653,11 @@ void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
 /*
  * Change data bus width and DDR mode of a host.
  */
-void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr)
+void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width,
+			   unsigned int ddr)
 {
 	host->ios.bus_width = width;
-	host->ios.ddr = ddr ? MMC_DDR_MODE : MMC_SDR_MODE;
+	host->ios.ddr = ddr;
 	mmc_set_ios(host);
 }
 
@@ -665,7 +666,7 @@ void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr)
  */
 void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
 {
-	mmc_set_bus_width_ddr(host, width, 0);
+	mmc_set_bus_width_ddr(host, width, MMC_SDR_MODE);
 }
 
 /**

drivers/mmc/core/core.h

@@ -35,7 +35,8 @@ void mmc_set_chip_select(struct mmc_host *host, int mode);
 void mmc_set_clock(struct mmc_host *host, unsigned int hz);
 void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode);
 void mmc_set_bus_width(struct mmc_host *host, unsigned int width);
-void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr);
+void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width,
+			   unsigned int ddr);
 u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
 void mmc_set_timing(struct mmc_host *host, unsigned int timing);
 

drivers/mmc/core/mmc.c

@@ -375,7 +375,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	struct mmc_card *oldcard)
 {
 	struct mmc_card *card;
-	int err, ddr = 0;
+	int err, ddr = MMC_SDR_MODE;
 	u32 cid[4];
 	unsigned int max_dtr;
 
@@ -523,10 +523,10 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	if (mmc_card_highspeed(card)) {
 		if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
 			&& (host->caps & (MMC_CAP_1_8V_DDR)))
-				ddr = 1;
+				ddr = MMC_1_8V_DDR_MODE;
 		else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
 			&& (host->caps & (MMC_CAP_1_2V_DDR)))
-				ddr = 1;
+				ddr = MMC_1_2V_DDR_MODE;
 	}
 
 	/*

include/linux/mmc/host.h

@@ -54,7 +54,8 @@ struct mmc_ios {
 	unsigned char	ddr;			/* dual data rate used */
 
 #define MMC_SDR_MODE		0
-#define MMC_DDR_MODE		1
+#define MMC_1_2V_DDR_MODE	1
+#define MMC_1_8V_DDR_MODE	2
 };
 
 struct mmc_host_ops {