1 files changed, 39 insertions, 29 deletions

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index ff2774128aa9..633975ff2bb3 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -409,52 +409,62 @@ out:
 
 static int sd_select_driver_type(struct mmc_card *card, u8 *status)
 {
-	int host_drv_type = 0, card_drv_type = 0;
+	int host_drv_type = SD_DRIVER_TYPE_B;
+	int card_drv_type = SD_DRIVER_TYPE_B;
+	int drive_strength;
 	int err;
 
 	/*
 	 * If the host doesn't support any of the Driver Types A,C or D,
-	 * default Driver Type B is used.
+	 * or there is no board specific handler then default Driver
+	 * Type B is used.
 	 */
 	if (!(card->host->caps & (MMC_CAP_DRIVER_TYPE_A | MMC_CAP_DRIVER_TYPE_C
 	    | MMC_CAP_DRIVER_TYPE_D)))
 		return 0;
 
-	if (card->host->caps & MMC_CAP_DRIVER_TYPE_A) {
-		host_drv_type = MMC_SET_DRIVER_TYPE_A;
-		if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_A)
-			card_drv_type = MMC_SET_DRIVER_TYPE_A;
-		else if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_B)
-			card_drv_type = MMC_SET_DRIVER_TYPE_B;
-		else if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_C)
-			card_drv_type = MMC_SET_DRIVER_TYPE_C;
-	} else if (card->host->caps & MMC_CAP_DRIVER_TYPE_C) {
-		host_drv_type = MMC_SET_DRIVER_TYPE_C;
-		if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_C)
-			card_drv_type = MMC_SET_DRIVER_TYPE_C;
-	} else if (!(card->host->caps & MMC_CAP_DRIVER_TYPE_D)) {
-		/*
-		 * If we are here, that means only the default driver type
-		 * B is supported by the host.
-		 */
-		host_drv_type = MMC_SET_DRIVER_TYPE_B;
-		if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_B)
-			card_drv_type = MMC_SET_DRIVER_TYPE_B;
-		else if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_C)
-			card_drv_type = MMC_SET_DRIVER_TYPE_C;
-	}
+	if (!card->host->ops->select_drive_strength)
+		return 0;
+
+	if (card->host->caps & MMC_CAP_DRIVER_TYPE_A)
+		host_drv_type |= SD_DRIVER_TYPE_A;
+
+	if (card->host->caps & MMC_CAP_DRIVER_TYPE_C)
+		host_drv_type |= SD_DRIVER_TYPE_C;
+
+	if (card->host->caps & MMC_CAP_DRIVER_TYPE_D)
+		host_drv_type |= SD_DRIVER_TYPE_D;
+
+	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_A)
+		card_drv_type |= SD_DRIVER_TYPE_A;
+
+	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_C)
+		card_drv_type |= SD_DRIVER_TYPE_C;
+
+	if (card->sw_caps.sd3_drv_type & SD_DRIVER_TYPE_D)
+		card_drv_type |= SD_DRIVER_TYPE_D;
+
+	/*
+	 * The drive strength that the hardware can support
+	 * depends on the board design.  Pass the appropriate
+	 * information and let the hardware specific code
+	 * return what is possible given the options
+	 */
+	drive_strength = card->host->ops->select_drive_strength(
+		card->sw_caps.uhs_max_dtr,
+		host_drv_type, card_drv_type);
 
-	err = mmc_sd_switch(card, 1, 2, card_drv_type, status);
+	err = mmc_sd_switch(card, 1, 2, drive_strength, status);
 	if (err)
 		return err;
 
-	if ((status[15] & 0xF) != card_drv_type) {
-		printk(KERN_WARNING "%s: Problem setting driver strength!\n",
+	if ((status[15] & 0xF) != drive_strength) {
+		printk(KERN_WARNING "%s: Problem setting drive strength!\n",
 			mmc_hostname(card->host));
 		return 0;
 	}
 
-	mmc_set_driver_type(card->host, host_drv_type);
+	mmc_set_driver_type(card->host, drive_strength);
 
 	return 0;
 }