diff --git a/arch/arm/mach-socfpga/xload.c b/arch/arm/mach-socfpga/xload.c
index 272896b..cf05ff3 100644
--- a/arch/arm/mach-socfpga/xload.c
+++ b/arch/arm/mach-socfpga/xload.c
@@ -10,6 +10,7 @@
 #include <linux/sizes.h>
 #include <fs.h>
 #include <io.h>
+#include <mci.h>
 
 #include <linux/clkdev.h>
 #include <linux/stat.h>
@@ -33,6 +34,7 @@
 static struct clk *clks[clk_max];
 
 static struct dw_mmc_platform_data mmc_pdata = {
+	.bus_width_caps = MMC_CAP_4_BIT_DATA,
 	.ciu_div = 3,
 };
 
diff --git a/drivers/mci/dw_mmc.c b/drivers/mci/dw_mmc.c
index acdf795..cbd3f00 100644
--- a/drivers/mci/dw_mmc.c
+++ b/drivers/mci/dw_mmc.c
@@ -676,11 +676,9 @@
 static int dw_mmc_probe(struct device_d *dev)
 {
 	struct dwmci_host *host;
-	struct mci_host *mci;
 	struct dw_mmc_platform_data *pdata = dev->platform_data;
 
 	host = xzalloc(sizeof(*host));
-	mci = &host->mci;
 
 	host->clk_biu = clk_get(dev, "biu");
 	if (IS_ERR(host->clk_biu))
@@ -698,20 +696,6 @@
 	if (IS_ERR(host->ioaddr))
 		return PTR_ERR(host->ioaddr);
 
-	if (pdata) {
-		mci->devname = pdata->devname;
-		host->ciu_div = pdata->ciu_div;
-	} else if (dev->device_node) {
-		const char *alias = of_alias_get(dev->device_node);
-		if (alias)
-			mci->devname = xstrdup(alias);
-		of_property_read_u32(dev->device_node, "dw-mshc-ciu-div",
-				&host->ciu_div);
-	}
-
-	/* divider is 0 based in pdata and 1 based in our private struct */
-	host->ciu_div++;
-
 	host->idmac = dma_alloc_coherent(sizeof(*host->idmac) * DW_MMC_NUM_IDMACS,
 					 DMA_ADDRESS_BROKEN);
 
@@ -722,6 +706,23 @@
 	host->mci.hw_dev = dev;
 	host->mci.voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
 	host->mci.host_caps = MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
+	host->mci.host_caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED_52MHZ |
+			       MMC_CAP_SD_HIGHSPEED;
+
+	if (pdata) {
+		host->ciu_div = pdata->ciu_div;
+		host->mci.host_caps &= ~MMC_CAP_BIT_DATA_MASK;
+		host->mci.host_caps |= pdata->bus_width_caps;
+	} else if (dev->device_node) {
+		const char *alias = of_alias_get(dev->device_node);
+		if (alias)
+			host->mci.devname = xstrdup(alias);
+		of_property_read_u32(dev->device_node, "dw-mshc-ciu-div",
+				&host->ciu_div);
+	}
+
+	/* divider is 0 based in pdata and 1 based in our private struct */
+	host->ciu_div++;
 
 	if (of_device_is_compatible(dev->device_node,
 	    "rockchip,rk2928-dw-mshc"))
diff --git a/drivers/mci/mci-core.c b/drivers/mci/mci-core.c
index 29c0d54..4e6b83b 100644
--- a/drivers/mci/mci-core.c
+++ b/drivers/mci/mci-core.c
@@ -1819,23 +1819,29 @@
 
 	/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
 	if (of_property_read_u32(np, "bus-width", &bus_width) < 0) {
+		/* If bus-width is missing we get the driver's default, which
+		 * is, unfortunately, not consistent from driver to driver.
+		 * Better to specify it in the device tree.  */
 		dev_dbg(host->hw_dev,
-			"\"bus-width\" property is missing, assuming 1 bit.\n");
-		bus_width = 1;
-	}
-
-	switch (bus_width) {
-	case 8:
-		host->host_caps |= MMC_CAP_8_BIT_DATA;
-		/* Hosts capable of 8-bit transfers can also do 4 bits */
-	case 4:
-		host->host_caps |= MMC_CAP_4_BIT_DATA;
-		break;
-	case 1:
-		break;
-	default:
-		dev_err(host->hw_dev,
-			"Invalid \"bus-width\" value %u!\n", bus_width);
+			"\"bus-width\" property missing, default is %d\n",
+			(host->host_caps & MMC_CAP_8_BIT_DATA) ? 8 :
+			(host->host_caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
+	} else {
+		/* Set data width caps to exactly those specified in the DT.
+		 * bus-width isn't a list, so widths smaller than the specified
+		 * value are implictly supported as well.  */
+		host->host_caps &= ~MMC_CAP_BIT_DATA_MASK;
+		switch (bus_width) {
+		case 8:
+			host->host_caps |= MMC_CAP_8_BIT_DATA;
+		case 4: /* note fall through from above */
+			host->host_caps |= MMC_CAP_4_BIT_DATA;
+		case 1:
+			break;
+		default:
+			dev_err(host->hw_dev,
+				"Invalid \"bus-width\" value %u!\n", bus_width);
+		}
 	}
 
 	/* f_max is obtained from the optional "max-frequency" property */
diff --git a/include/mci.h b/include/mci.h
index 41a757e..174d150 100644
--- a/include/mci.h
+++ b/include/mci.h
@@ -56,6 +56,8 @@
 #define MMC_CAP_SD_HIGHSPEED		(1 << 3)
 #define MMC_CAP_MMC_HIGHSPEED		(1 << 4)
 #define MMC_CAP_MMC_HIGHSPEED_52MHZ	(1 << 5)
+/* Mask of all caps for bus width */
+#define MMC_CAP_BIT_DATA_MASK		(MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA)
 
 #define SD_DATA_4BIT		0x00040000
 
diff --git a/include/platform_data/dw_mmc.h b/include/platform_data/dw_mmc.h
index 48faa76..4325a4f 100644
--- a/include/platform_data/dw_mmc.h
+++ b/include/platform_data/dw_mmc.h
@@ -2,7 +2,7 @@
 #define __INCLUDE_PLATFORM_DATA_DW_MMC_H
 
 struct dw_mmc_platform_data {
-	char *devname;
+	unsigned int bus_width_caps;
 	int ciu_div;
 };