diff --git a/drivers/usb/host/ehci-mx6.c b/drivers/usb/host/ehci-mx6.c
index 1bd6147c76a..060b02accc5 100644
--- a/drivers/usb/host/ehci-mx6.c
+++ b/drivers/usb/host/ehci-mx6.c
@@ -543,7 +543,7 @@ static int ehci_usb_phy_mode(struct udevice *dev)
 			plat->init_type = USB_INIT_DEVICE;
 		else
 			plat->init_type = USB_INIT_HOST;
-	} else if (is_mx7()) {
+	} else if (is_mx7() || is_imx8mm() || is_imx8mn()) {
 		phy_status = (void __iomem *)(addr +
 					      USBNC_PHY_STATUS_OFFSET);
 		val = readl(phy_status);
@@ -573,9 +573,8 @@ static int ehci_usb_of_to_plat(struct udevice *dev)
 	case USB_DR_MODE_PERIPHERAL:
 		plat->init_type = USB_INIT_DEVICE;
 		break;
-	case USB_DR_MODE_OTG:
-	case USB_DR_MODE_UNKNOWN:
-		return ehci_usb_phy_mode(dev);
+	default:
+		plat->init_type = USB_INIT_UNKNOWN;
 	};
 
 	return 0;
@@ -677,6 +676,20 @@ static int ehci_usb_probe(struct udevice *dev)
 	mdelay(1);
 #endif
 
+	/*
+	 * If the device tree didn't specify host or device,
+	 * the default is USB_INIT_UNKNOWN, so we need to check
+	 * the register. For imx8mm and imx8mn, the clocks need to be
+	 * running first, so we defer the check until they are.
+	 */
+	if (priv->init_type == USB_INIT_UNKNOWN) {
+		ret = ehci_usb_phy_mode(dev);
+		if (ret)
+			goto err_clk;
+		else
+			priv->init_type = plat->init_type;
+	}
+
 #if CONFIG_IS_ENABLED(DM_REGULATOR)
 	ret = device_get_supply_regulator(dev, "vbus-supply",
 					  &priv->vbus_supply);
@@ -741,8 +754,8 @@ err_regulator:
 #if CONFIG_IS_ENABLED(DM_REGULATOR)
 	if (priv->vbus_supply)
 		regulator_set_enable(priv->vbus_supply, false);
-err_clk:
 #endif
+err_clk:
 #if CONFIG_IS_ENABLED(CLK)
 	clk_disable(&priv->clk);
 #else
diff --git a/include/usb.h b/include/usb.h
index f032de8af93..7e3796bd5ba 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -163,7 +163,8 @@ struct int_queue;
  */
 enum usb_init_type {
 	USB_INIT_HOST,
-	USB_INIT_DEVICE
+	USB_INIT_DEVICE,
+	USB_INIT_UNKNOWN,
 };
 
 /**********************************************************************