---

yaml
---
r: 255223
b: refs/heads/master
c: ca8e99b
h: refs/heads/master
i:
  255221: bc98d78
  255219: a369ebe
  255215: 9f25f10
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ee8a43a51c7681f19fe23b6b936e1d8094a8b7d1
+refs/heads/master: ca8e99b32e3863c98ac958617cc157a00bf445b8

trunk/drivers/mmc/core/sd.c

@@ -409,52 +409,62 @@ int mmc_sd_switch_hs(struct mmc_card *card)
 
 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;
 }

trunk/include/linux/mmc/host.h

@@ -148,6 +148,7 @@ struct mmc_host_ops {
 	int	(*start_signal_voltage_switch)(struct mmc_host *host, struct mmc_ios *ios);
 	int	(*execute_tuning)(struct mmc_host *host);
 	void	(*enable_preset_value)(struct mmc_host *host, bool enable);
+	int	(*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv);
 };
 
 struct mmc_card;