diff --git a/common/usb.c b/common/usb.c
index 0904259..8d27bc7 100644
--- a/common/usb.c
+++ b/common/usb.c
@@ -437,12 +437,13 @@ static int usb_parse_config(struct usb_device *dev,
 			}
 			break;
 		case USB_DT_ENDPOINT:
-			if (head->bLength != USB_DT_ENDPOINT_SIZE) {
+			if (head->bLength != USB_DT_ENDPOINT_SIZE &&
+			    head->bLength != USB_DT_ENDPOINT_AUDIO_SIZE) {
 				printf("ERROR: Invalid USB EP length (%d)\n",
 					head->bLength);
 				break;
 			}
-			if (index + USB_DT_ENDPOINT_SIZE >
+			if (index + head->bLength >
 			    dev->config.desc.wTotalLength) {
 				puts("USB EP descriptor overflowed buffer!\n");
 				break;
@@ -969,23 +970,24 @@ static int usb_setup_descriptor(struct usb_device *dev, bool do_read)
 	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
 	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
 
-	if (do_read) {
+	if (do_read && dev->speed == USB_SPEED_FULL) {
 		int err;
 
 		/*
-		 * Validate we've received only at least 8 bytes, not that we've
-		 * received the entire descriptor. The reasoning is:
-		 * - The code only uses fields in the first 8 bytes, so that's all we
-		 *   need to have fetched at this stage.
-		 * - The smallest maxpacket size is 8 bytes. Before we know the actual
-		 *   maxpacket the device uses, the USB controller may only accept a
-		 *   single packet. Consequently we are only guaranteed to receive 1
-		 *   packet (at least 8 bytes) even in a non-error case.
+		 * Validate we've received only at least 8 bytes, not that
+		 * we've received the entire descriptor. The reasoning is:
+		 * - The code only uses fields in the first 8 bytes, so
+		 *   that's all we need to have fetched at this stage.
+		 * - The smallest maxpacket size is 8 bytes. Before we know
+		 *   the actual maxpacket the device uses, the USB controller
+		 *   may only accept a single packet. Consequently we are only
+		 *   guaranteed to receive 1 packet (at least 8 bytes) even in
+		 *   a non-error case.
 		 *
-		 * At least the DWC2 controller needs to be programmed with the number
-		 * of packets in addition to the number of bytes. A request for 64
-		 * bytes of data with the maxpacket guessed as 64 (above) yields a
-		 * request for 1 packet.
+		 * At least the DWC2 controller needs to be programmed with
+		 * the number of packets in addition to the number of bytes.
+		 * A request for 64 bytes of data with the maxpacket guessed
+		 * as 64 (above) yields a request for 1 packet.
 		 */
 		err = get_descriptor_len(dev, 64, 8);
 		if (err)
@@ -1008,7 +1010,7 @@ static int usb_setup_descriptor(struct usb_device *dev, bool do_read)
 		dev->maxpacketsize = PACKET_SIZE_64;
 		break;
 	default:
-		printf("usb_new_device: invalid max packet size\n");
+		printf("%s: invalid max packet size\n", __func__);
 		return -EIO;
 	}
 
@@ -1050,6 +1052,17 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read,
 
 	mdelay(10);	/* Let the SET_ADDRESS settle */
 
+	/*
+	 * If we haven't read device descriptor before, read it here
+	 * after device is assigned an address. This is only applicable
+	 * to xHCI so far.
+	 */
+	if (!do_read) {
+		err = usb_setup_descriptor(dev, true);
+		if (err)
+			return err;
+	}
+
 	return 0;
 }
 
diff --git a/common/usb_hub.c b/common/usb_hub.c
index 86a3477..325d16d 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -489,6 +489,17 @@ static int usb_scan_port(struct usb_device_scan *usb_scan)
 		return 0;
 	}
 
+	if (portchange & USB_PORT_STAT_C_RESET) {
+		debug("port %d reset change\n", i + 1);
+		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_RESET);
+	}
+
+	if ((portchange & USB_SS_PORT_STAT_C_BH_RESET) &&
+	    usb_hub_is_superspeed(dev)) {
+		debug("port %d BH reset change\n", i + 1);
+		usb_clear_port_feature(dev, i + 1, USB_SS_PORT_FEAT_C_BH_RESET);
+	}
+
 	/* A new USB device is ready at this point */
 	debug("devnum=%d port=%d: USB dev found\n", dev->devnum, i + 1);
 
@@ -543,11 +554,6 @@ static int usb_scan_port(struct usb_device_scan *usb_scan)
 		       hub->overcurrent_count[i]);
 	}
 
-	if (portchange & USB_PORT_STAT_C_RESET) {
-		debug("port %d reset change\n", i + 1);
-		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_RESET);
-	}
-
 	/*
 	 * We're done with this device, so let's remove this device from
 	 * scanning list
diff --git a/common/usb_storage.c b/common/usb_storage.c
index a57570b..a91b1c0 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -964,7 +964,7 @@ static void usb_stor_set_max_xfer_blk(struct usb_device *udev,
 		blk = 20;
 	} else {
 		if (size > USHRT_MAX * 512)
-			blk = USHRT_MAX;
+			size = USHRT_MAX * 512;
 		blk = size / 512;
 	}
 #endif
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index a291ceb..ae7fc1c 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -37,6 +37,13 @@ config USB_DWC3_OMAP
 
 	  Say 'Y' here if you have one such device
 
+config USB_DWC3_UNIPHIER
+	bool "DesignWare USB3 Host Support on UniPhier Platforms"
+	depends on ARCH_UNIPHIER && USB_XHCI_DWC3
+	help
+	  Support of USB2/3 functionality in Socionext UniPhier platforms.
+	  Say 'Y' here if you have one such device.
+
 menu "PHY Subsystem"
 
 config USB_DWC3_PHY_OMAP
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index 2964bae..5149776 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -9,5 +9,6 @@ dwc3-y					:= core.o
 obj-$(CONFIG_USB_DWC3_GADGET)		+= gadget.o ep0.o
 
 obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
+obj-$(CONFIG_USB_DWC3_UNIPHIER)		+= dwc3-uniphier.o
 obj-$(CONFIG_USB_DWC3_PHY_OMAP)		+= ti_usb_phy.o
 obj-$(CONFIG_USB_DWC3_PHY_SAMSUNG)	+= samsung_usb_phy.o
diff --git a/drivers/usb/dwc3/dwc3-uniphier.c b/drivers/usb/dwc3/dwc3-uniphier.c
new file mode 100644
index 0000000..0d13770
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-uniphier.c
@@ -0,0 +1,120 @@
+/*
+ * UniPhier Specific Glue Layer for DWC3
+ *
+ * Copyright (C) 2016-2017 Socionext Inc.
+ *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/sizes.h>
+
+#define UNIPHIER_PRO4_DWC3_RESET	0x40
+#define   UNIPHIER_PRO4_DWC3_RESET_XIOMMU	BIT(5)
+#define   UNIPHIER_PRO4_DWC3_RESET_XLINK	BIT(4)
+#define   UNIPHIER_PRO4_DWC3_RESET_PHY_SS	BIT(2)
+
+#define UNIPHIER_PRO5_DWC3_RESET	0x00
+#define   UNIPHIER_PRO5_DWC3_RESET_PHY_S1	BIT(17)
+#define   UNIPHIER_PRO5_DWC3_RESET_PHY_S0	BIT(16)
+#define   UNIPHIER_PRO5_DWC3_RESET_XLINK	BIT(15)
+#define   UNIPHIER_PRO5_DWC3_RESET_XIOMMU	BIT(14)
+
+#define UNIPHIER_PXS2_DWC3_RESET	0x00
+#define   UNIPHIER_PXS2_DWC3_RESET_XLINK	BIT(15)
+
+static int uniphier_pro4_dwc3_init(void __iomem *regs)
+{
+	u32 tmp;
+
+	tmp = readl(regs + UNIPHIER_PRO4_DWC3_RESET);
+	tmp &= ~UNIPHIER_PRO4_DWC3_RESET_PHY_SS;
+	tmp |= UNIPHIER_PRO4_DWC3_RESET_XIOMMU | UNIPHIER_PRO4_DWC3_RESET_XLINK;
+	writel(tmp, regs + UNIPHIER_PRO4_DWC3_RESET);
+
+	return 0;
+}
+
+static int uniphier_pro5_dwc3_init(void __iomem *regs)
+{
+	u32 tmp;
+
+	tmp = readl(regs + UNIPHIER_PRO5_DWC3_RESET);
+	tmp &= ~(UNIPHIER_PRO5_DWC3_RESET_PHY_S1 |
+		 UNIPHIER_PRO5_DWC3_RESET_PHY_S0);
+	tmp |= UNIPHIER_PRO5_DWC3_RESET_XLINK | UNIPHIER_PRO5_DWC3_RESET_XIOMMU;
+	writel(tmp, regs + UNIPHIER_PRO5_DWC3_RESET);
+
+	return 0;
+}
+
+static int uniphier_pxs2_dwc3_init(void __iomem *regs)
+{
+	u32 tmp;
+
+	tmp = readl(regs + UNIPHIER_PXS2_DWC3_RESET);
+	tmp |= UNIPHIER_PXS2_DWC3_RESET_XLINK;
+	writel(tmp, regs + UNIPHIER_PXS2_DWC3_RESET);
+
+	return 0;
+}
+
+static int uniphier_dwc3_probe(struct udevice *dev)
+{
+	fdt_addr_t base;
+	void __iomem *regs;
+	int (*init)(void __iomem *regs);
+	int ret;
+
+	base = devfdt_get_addr(dev);
+	if (base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	regs = ioremap(base, SZ_32K);
+	if (!regs)
+		return -ENOMEM;
+
+	init = (typeof(init))dev_get_driver_data(dev);
+	ret = init(regs);
+	if (ret)
+		dev_err(dev, "failed to init glue layer\n");
+
+	iounmap(regs);
+
+	return ret;
+}
+
+static const struct udevice_id uniphier_dwc3_match[] = {
+	{
+		.compatible = "socionext,uniphier-pro4-dwc3",
+		.data = (ulong)uniphier_pro4_dwc3_init,
+	},
+	{
+		.compatible = "socionext,uniphier-pro5-dwc3",
+		.data = (ulong)uniphier_pro5_dwc3_init,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-dwc3",
+		.data = (ulong)uniphier_pxs2_dwc3_init,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-dwc3",
+		.data = (ulong)uniphier_pxs2_dwc3_init,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs3-dwc3",
+		.data = (ulong)uniphier_pxs2_dwc3_init,
+	},
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(usb_xhci) = {
+	.name = "uniphier-dwc3",
+	.id = UCLASS_SIMPLE_BUS,
+	.of_match = uniphier_dwc3_match,
+	.probe = uniphier_dwc3_probe,
+};
diff --git a/drivers/usb/emul/sandbox_flash.c b/drivers/usb/emul/sandbox_flash.c
index 98d20c0..2f84b36 100644
--- a/drivers/usb/emul/sandbox_flash.c
+++ b/drivers/usb/emul/sandbox_flash.c
@@ -390,8 +390,7 @@ static int sandbox_flash_bind(struct udevice *dev)
 	fs[2].id = STRINGID_SERIAL;
 	fs[2].s = dev->name;
 
-	return usb_emul_setup_device(dev, PACKET_SIZE_64, plat->flash_strings,
-				     flash_desc_list);
+	return usb_emul_setup_device(dev, plat->flash_strings, flash_desc_list);
 }
 
 static int sandbox_flash_probe(struct udevice *dev)
diff --git a/drivers/usb/emul/sandbox_hub.c b/drivers/usb/emul/sandbox_hub.c
index 1432858..9a0f47b 100644
--- a/drivers/usb/emul/sandbox_hub.c
+++ b/drivers/usb/emul/sandbox_hub.c
@@ -121,9 +121,12 @@ struct sandbox_hub_priv {
 	int change[SANDBOX_NUM_PORTS];
 };
 
-static struct udevice *hub_find_device(struct udevice *hub, int port)
+static struct udevice *hub_find_device(struct udevice *hub, int port,
+				       enum usb_device_speed *speed)
 {
 	struct udevice *dev;
+	struct usb_generic_descriptor **gen_desc;
+	struct usb_device_descriptor **dev_desc;
 
 	for (device_find_first_child(hub, &dev);
 	     dev;
@@ -131,8 +134,27 @@ static struct udevice *hub_find_device(struct udevice *hub, int port)
 		struct sandbox_hub_platdata *plat;
 
 		plat = dev_get_parent_platdata(dev);
-		if (plat->port == port)
+		if (plat->port == port) {
+			gen_desc = plat->plat.desc_list;
+			gen_desc = usb_emul_find_descriptor(gen_desc,
+							    USB_DT_DEVICE, 0);
+			dev_desc = (struct usb_device_descriptor **)gen_desc;
+
+			switch (le16_to_cpu((*dev_desc)->bcdUSB)) {
+			case 0x0100:
+				*speed = USB_SPEED_LOW;
+				break;
+			case 0x0101:
+				*speed = USB_SPEED_FULL;
+				break;
+			case 0x0200:
+			default:
+				*speed = USB_SPEED_HIGH;
+				break;
+			}
+
 			return dev;
+		}
 	}
 
 	return NULL;
@@ -146,7 +168,8 @@ static int clrset_post_state(struct udevice *hub, int port, int clear, int set)
 	int ret = 0;
 
 	if ((clear | set) & USB_PORT_STAT_POWER) {
-		struct udevice *dev = hub_find_device(hub, port);
+		enum usb_device_speed speed;
+		struct udevice *dev = hub_find_device(hub, port, &speed);
 
 		if (dev) {
 			if (set & USB_PORT_STAT_POWER) {
@@ -156,6 +179,10 @@ static int clrset_post_state(struct udevice *hub, int port, int clear, int set)
 				if (!ret) {
 					set |= USB_PORT_STAT_CONNECTION |
 						USB_PORT_STAT_ENABLE;
+					if (speed == USB_SPEED_LOW)
+						set |= USB_PORT_STAT_LOW_SPEED;
+					else if (speed == USB_SPEED_HIGH)
+						set |= USB_PORT_STAT_HIGH_SPEED;
 				}
 
 			} else if (clear & USB_PORT_STAT_POWER) {
@@ -274,15 +301,16 @@ static int sandbox_hub_submit_control_msg(struct udevice *bus,
 
 static int sandbox_hub_bind(struct udevice *dev)
 {
-	return usb_emul_setup_device(dev, PACKET_SIZE_64, hub_strings,
-				     hub_desc_list);
+	return usb_emul_setup_device(dev, hub_strings, hub_desc_list);
 }
 
 static int sandbox_child_post_bind(struct udevice *dev)
 {
 	struct sandbox_hub_platdata *plat = dev_get_parent_platdata(dev);
+	struct usb_emul_platdata *emul = dev_get_uclass_platdata(dev);
 
 	plat->port = dev_read_u32_default(dev, "reg", -1);
+	emul->port1 = plat->port + 1;
 
 	return 0;
 }
diff --git a/drivers/usb/emul/sandbox_keyb.c b/drivers/usb/emul/sandbox_keyb.c
index 2735985..cff0176 100644
--- a/drivers/usb/emul/sandbox_keyb.c
+++ b/drivers/usb/emul/sandbox_keyb.c
@@ -208,8 +208,7 @@ static int sandbox_keyb_bind(struct udevice *dev)
 	fs[2].id = STRINGID_SERIAL;
 	fs[2].s = dev->name;
 
-	return usb_emul_setup_device(dev, PACKET_SIZE_8, plat->keyb_strings,
-				     keyb_desc_list);
+	return usb_emul_setup_device(dev, plat->keyb_strings, keyb_desc_list);
 }
 
 static int sandbox_keyb_probe(struct udevice *dev)
diff --git a/drivers/usb/emul/usb-emul-uclass.c b/drivers/usb/emul/usb-emul-uclass.c
index 6e03c1e..fbe11f3 100644
--- a/drivers/usb/emul/usb-emul-uclass.c
+++ b/drivers/usb/emul/usb-emul-uclass.c
@@ -52,7 +52,7 @@ static int usb_emul_get_string(struct usb_string *strings, int index,
 	return -EINVAL;
 }
 
-static struct usb_generic_descriptor **find_descriptor(
+struct usb_generic_descriptor **usb_emul_find_descriptor(
 		struct usb_generic_descriptor **ptr, int type, int index)
 {
 	debug("%s: type=%x, index=%d\n", __func__, type, index);
@@ -91,8 +91,7 @@ static int usb_emul_get_descriptor(struct usb_dev_platdata *plat, int value,
 					   length);
 	}
 
-	ptr = find_descriptor((struct usb_generic_descriptor **)plat->desc_list,
-			      type, index);
+	ptr = usb_emul_find_descriptor(plat->desc_list, type, index);
 	if (!ptr) {
 		debug("%s: Could not find descriptor type %d, index %d\n",
 		      __func__, type, index);
@@ -107,7 +106,7 @@ static int usb_emul_get_descriptor(struct usb_dev_platdata *plat, int value,
 	return upto ? upto : length ? -EIO : 0;
 }
 
-static int usb_emul_find_devnum(int devnum, struct udevice **emulp)
+static int usb_emul_find_devnum(int devnum, int port1, struct udevice **emulp)
 {
 	struct udevice *dev;
 	struct uclass *uc;
@@ -120,7 +119,37 @@ static int usb_emul_find_devnum(int devnum, struct udevice **emulp)
 	uclass_foreach_dev(dev, uc) {
 		struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
 
-		if (udev->devnum == devnum) {
+		/*
+		 * devnum is initialzied to zero at the beginning of the
+		 * enumeration process in usb_setup_device(). At this
+		 * point, udev->devnum has not been assigned to any valid
+		 * USB address either, so we can't rely on the comparison
+		 * result between udev->devnum and devnum to select an
+		 * emulator device.
+		 */
+		if (!devnum) {
+			struct usb_emul_platdata *plat;
+
+			/*
+			 * If the parent is sandbox USB controller, we are
+			 * the root hub. And there is only one root hub
+			 * in the system.
+			 */
+			if (device_get_uclass_id(dev->parent) == UCLASS_USB) {
+				debug("%s: Found emulator '%s'\n",
+				      __func__, dev->name);
+				*emulp = dev;
+				return 0;
+			}
+
+			plat = dev_get_uclass_platdata(dev);
+			if (plat->port1 == port1) {
+				debug("%s: Found emulator '%s', port %d\n",
+				      __func__, dev->name, port1);
+				*emulp = dev;
+				return 0;
+			}
+		} else if (udev->devnum == devnum) {
 			debug("%s: Found emulator '%s', addr %d\n", __func__,
 			      dev->name, udev->devnum);
 			*emulp = dev;
@@ -132,18 +161,19 @@ static int usb_emul_find_devnum(int devnum, struct udevice **emulp)
 	return -ENOENT;
 }
 
-int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp)
+int usb_emul_find(struct udevice *bus, ulong pipe, int port1,
+		  struct udevice **emulp)
 {
 	int devnum = usb_pipedevice(pipe);
 
-	return usb_emul_find_devnum(devnum, emulp);
+	return usb_emul_find_devnum(devnum, port1, emulp);
 }
 
 int usb_emul_find_for_dev(struct udevice *dev, struct udevice **emulp)
 {
 	struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
 
-	return usb_emul_find_devnum(udev->devnum, emulp);
+	return usb_emul_find_devnum(udev->devnum, 0, emulp);
 }
 
 int usb_emul_control(struct udevice *emul, struct usb_device *udev,
@@ -229,8 +259,8 @@ int usb_emul_int(struct udevice *emul, struct usb_device *udev,
 	return ops->interrupt(emul, udev, pipe, buffer, length, interval);
 }
 
-int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
-			  struct usb_string *strings, void **desc_list)
+int usb_emul_setup_device(struct udevice *dev, struct usb_string *strings,
+			  void **desc_list)
 {
 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 	struct usb_generic_descriptor **ptr;
@@ -264,18 +294,11 @@ int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
 	return 0;
 }
 
-void usb_emul_reset(struct udevice *dev)
-{
-	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
-
-	plat->devnum = 0;
-	plat->configno = 0;
-}
-
 UCLASS_DRIVER(usb_emul) = {
 	.id		= UCLASS_USB_EMUL,
 	.name		= "usb_emul",
 	.post_bind	= dm_scan_fdt_dev,
+	.per_device_platdata_auto_alloc_size = sizeof(struct usb_emul_platdata),
 	.per_child_auto_alloc_size = sizeof(struct usb_device),
 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
 };
diff --git a/drivers/usb/host/usb-sandbox.c b/drivers/usb/host/usb-sandbox.c
index 5e3d96c..15055b3 100644
--- a/drivers/usb/host/usb-sandbox.c
+++ b/drivers/usb/host/usb-sandbox.c
@@ -12,6 +12,10 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+struct sandbox_usb_ctrl {
+	int rootdev;
+};
+
 static void usbmon_trace(struct udevice *bus, ulong pipe,
 			 struct devrequest *setup, struct udevice *emul)
 {
@@ -40,15 +44,24 @@ static int sandbox_submit_control(struct udevice *bus,
 				      void *buffer, int length,
 				      struct devrequest *setup)
 {
+	struct sandbox_usb_ctrl *ctrl = dev_get_priv(bus);
 	struct udevice *emul;
 	int ret;
 
 	/* Just use child of dev as emulator? */
 	debug("%s: bus=%s\n", __func__, bus->name);
-	ret = usb_emul_find(bus, pipe, &emul);
+	ret = usb_emul_find(bus, pipe, udev->portnr, &emul);
 	usbmon_trace(bus, pipe, setup, emul);
 	if (ret)
 		return ret;
+
+	if (usb_pipedevice(pipe) == ctrl->rootdev) {
+		if (setup->request == USB_REQ_SET_ADDRESS) {
+			debug("%s: Set root hub's USB address\n", __func__);
+			ctrl->rootdev = le16_to_cpu(setup->value);
+		}
+	}
+
 	ret = usb_emul_control(emul, udev, pipe, buffer, length, setup);
 	if (ret < 0) {
 		debug("ret=%d\n", ret);
@@ -70,7 +83,7 @@ static int sandbox_submit_bulk(struct udevice *bus, struct usb_device *udev,
 
 	/* Just use child of dev as emulator? */
 	debug("%s: bus=%s\n", __func__, bus->name);
-	ret = usb_emul_find(bus, pipe, &emul);
+	ret = usb_emul_find(bus, pipe, udev->portnr, &emul);
 	usbmon_trace(bus, pipe, NULL, emul);
 	if (ret)
 		return ret;
@@ -96,7 +109,7 @@ static int sandbox_submit_int(struct udevice *bus, struct usb_device *udev,
 
 	/* Just use child of dev as emulator? */
 	debug("%s: bus=%s\n", __func__, bus->name);
-	ret = usb_emul_find(bus, pipe, &emul);
+	ret = usb_emul_find(bus, pipe, udev->portnr, &emul);
 	usbmon_trace(bus, pipe, NULL, emul);
 	if (ret)
 		return ret;
@@ -107,6 +120,16 @@ static int sandbox_submit_int(struct udevice *bus, struct usb_device *udev,
 
 static int sandbox_alloc_device(struct udevice *dev, struct usb_device *udev)
 {
+	struct sandbox_usb_ctrl *ctrl = dev_get_priv(dev);
+
+	/*
+	 * Root hub will be the first device to be initailized.
+	 * If this device is a root hub, initialize its device speed
+	 * to high speed as we are a USB 2.0 controller.
+	 */
+	if (ctrl->rootdev == 0)
+		udev->speed = USB_SPEED_HIGH;
+
 	return 0;
 }
 
@@ -133,4 +156,5 @@ U_BOOT_DRIVER(usb_sandbox) = {
 	.of_match = sandbox_usb_ids,
 	.probe = sandbox_usb_probe,
 	.ops	= &sandbox_usb_ops,
+	.priv_auto_alloc_size = sizeof(struct sandbox_usb_ctrl),
 };
diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
index bc44fc3..4e40f4b 100644
--- a/drivers/usb/host/usb-uclass.c
+++ b/drivers/usb/host/usb-uclass.c
@@ -164,6 +164,7 @@ int usb_get_max_xfer_size(struct usb_device *udev, size_t *size)
 int usb_stop(void)
 {
 	struct udevice *bus;
+	struct udevice *rh;
 	struct uclass *uc;
 	struct usb_uclass_priv *uc_priv;
 	int err = 0, ret;
@@ -179,23 +180,20 @@ int usb_stop(void)
 		ret = device_remove(bus, DM_REMOVE_NORMAL);
 		if (ret && !err)
 			err = ret;
-	}
-#ifdef CONFIG_BLK
-	ret = blk_unbind_all(IF_TYPE_USB);
-	if (ret && !err)
-		err = ret;
-#endif
-#ifdef CONFIG_SANDBOX
-	struct udevice *dev;
 
-	/* Reset all enulation devices */
-	ret = uclass_get(UCLASS_USB_EMUL, &uc);
-	if (ret)
-		return ret;
+		/* Locate root hub device */
+		device_find_first_child(bus, &rh);
+		if (rh) {
+			/*
+			 * All USB devices are children of root hub.
+			 * Unbinding root hub will unbind all of its children.
+			 */
+			ret = device_unbind(rh);
+			if (ret && !err)
+				err = ret;
+		}
+	}
 
-	uclass_foreach_dev(dev, uc)
-		usb_emul_reset(dev);
-#endif
 #ifdef CONFIG_USB_STORAGE
 	usb_stor_reset();
 #endif
@@ -262,6 +260,21 @@ int usb_init(void)
 		/* init low_level USB */
 		printf("USB%d:   ", count);
 		count++;
+
+#ifdef CONFIG_SANDBOX
+		/*
+		 * For Sandbox, we need scan the device tree each time when we
+		 * start the USB stack, in order to re-create the emulated USB
+		 * devices and bind drivers for them before we actually do the
+		 * driver probe.
+		 */
+		ret = dm_scan_fdt_dev(bus);
+		if (ret) {
+			printf("Sandbox USB device scan failed (%d)\n", ret);
+			continue;
+		}
+#endif
+
 		ret = device_probe(bus);
 		if (ret == -ENODEV) {	/* No such device. */
 			puts("Port not available.\n");
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index d5eab3a..0582a9b 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -786,12 +786,22 @@ void xhci_setup_addressable_virt_dev(struct xhci_ctrl *ctrl,
 #ifdef CONFIG_DM_USB
 	/* Set up TT fields to support FS/LS devices */
 	if (speed == USB_SPEED_LOW || speed == USB_SPEED_FULL) {
-		dev = dev_get_parent_priv(udev->dev);
-		if (dev->speed == USB_SPEED_HIGH) {
-			hub = dev_get_uclass_priv(udev->dev);
+		struct udevice *parent = udev->dev;
+
+		dev = udev;
+		do {
+			port_num = dev->portnr;
+			dev = dev_get_parent_priv(parent);
+			if (usb_hub_is_root_hub(dev->dev))
+				break;
+			parent = dev->dev->parent;
+		} while (dev->speed != USB_SPEED_HIGH);
+
+		if (!usb_hub_is_root_hub(dev->dev)) {
+			hub = dev_get_uclass_priv(dev->dev);
 			if (hub->tt.multi)
 				slot_ctx->dev_info |= cpu_to_le32(DEV_MTT);
-			slot_ctx->tt_info |= cpu_to_le32(TT_PORT(udev->portnr));
+			slot_ctx->tt_info |= cpu_to_le32(TT_PORT(port_num));
 			slot_ctx->tt_info |= cpu_to_le32(TT_SLOT(dev->slot_id));
 		}
 	}
@@ -840,6 +850,12 @@ void xhci_setup_addressable_virt_dev(struct xhci_ctrl *ctrl,
 	trb_64 = (uintptr_t)virt_dev->eps[0].ring->first_seg->trbs;
 	ep0_ctx->deq = cpu_to_le64(trb_64 | virt_dev->eps[0].ring->cycle_state);
 
+	/*
+	 * xHCI spec 6.2.3:
+	 * software shall set 'Average TRB Length' to 8 for control endpoints.
+	 */
+	ep0_ctx->tx_info = cpu_to_le32(EP_AVG_TRB_LENGTH(8));
+
 	/* Steps 7 and 8 were done in xhci_alloc_virt_device() */
 
 	xhci_flush_cache((uintptr_t)ep0_ctx, sizeof(struct xhci_ep_ctx));
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 04eb1eb..4673738 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -257,6 +257,188 @@ static unsigned int xhci_get_ep_index(struct usb_endpoint_descriptor *desc)
 	return index;
 }
 
+/*
+ * Convert bInterval expressed in microframes (in 1-255 range) to exponent of
+ * microframes, rounded down to nearest power of 2.
+ */
+static unsigned int xhci_microframes_to_exponent(unsigned int desc_interval,
+						 unsigned int min_exponent,
+						 unsigned int max_exponent)
+{
+	unsigned int interval;
+
+	interval = fls(desc_interval) - 1;
+	interval = clamp_val(interval, min_exponent, max_exponent);
+	if ((1 << interval) != desc_interval)
+		debug("rounding interval to %d microframes, "\
+		      "ep desc says %d microframes\n",
+		      1 << interval, desc_interval);
+
+	return interval;
+}
+
+static unsigned int xhci_parse_microframe_interval(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc)
+{
+	if (endpt_desc->bInterval == 0)
+		return 0;
+
+	return xhci_microframes_to_exponent(endpt_desc->bInterval, 0, 15);
+}
+
+static unsigned int xhci_parse_frame_interval(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc)
+{
+	return xhci_microframes_to_exponent(endpt_desc->bInterval * 8, 3, 10);
+}
+
+/*
+ * Convert interval expressed as 2^(bInterval - 1) == interval into
+ * straight exponent value 2^n == interval.
+ */
+static unsigned int xhci_parse_exponent_interval(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc)
+{
+	unsigned int interval;
+
+	interval = clamp_val(endpt_desc->bInterval, 1, 16) - 1;
+	if (interval != endpt_desc->bInterval - 1)
+		debug("ep %#x - rounding interval to %d %sframes\n",
+		      endpt_desc->bEndpointAddress, 1 << interval,
+		      udev->speed == USB_SPEED_FULL ? "" : "micro");
+
+	if (udev->speed == USB_SPEED_FULL) {
+		/*
+		 * Full speed isoc endpoints specify interval in frames,
+		 * not microframes. We are using microframes everywhere,
+		 * so adjust accordingly.
+		 */
+		interval += 3;	/* 1 frame = 2^3 uframes */
+	}
+
+	return interval;
+}
+
+/*
+ * Return the polling or NAK interval.
+ *
+ * The polling interval is expressed in "microframes". If xHCI's Interval field
+ * is set to N, it will service the endpoint every 2^(Interval)*125us.
+ *
+ * The NAK interval is one NAK per 1 to 255 microframes, or no NAKs if interval
+ * is set to 0.
+ */
+static unsigned int xhci_get_endpoint_interval(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc)
+{
+	unsigned int interval = 0;
+
+	switch (udev->speed) {
+	case USB_SPEED_HIGH:
+		/* Max NAK rate */
+		if (usb_endpoint_xfer_control(endpt_desc) ||
+		    usb_endpoint_xfer_bulk(endpt_desc)) {
+			interval = xhci_parse_microframe_interval(udev,
+								  endpt_desc);
+			break;
+		}
+		/* Fall through - SS and HS isoc/int have same decoding */
+
+	case USB_SPEED_SUPER:
+		if (usb_endpoint_xfer_int(endpt_desc) ||
+		    usb_endpoint_xfer_isoc(endpt_desc)) {
+			interval = xhci_parse_exponent_interval(udev,
+								endpt_desc);
+		}
+		break;
+
+	case USB_SPEED_FULL:
+		if (usb_endpoint_xfer_isoc(endpt_desc)) {
+			interval = xhci_parse_exponent_interval(udev,
+								endpt_desc);
+			break;
+		}
+		/*
+		 * Fall through for interrupt endpoint interval decoding
+		 * since it uses the same rules as low speed interrupt
+		 * endpoints.
+		 */
+
+	case USB_SPEED_LOW:
+		if (usb_endpoint_xfer_int(endpt_desc) ||
+		    usb_endpoint_xfer_isoc(endpt_desc)) {
+			interval = xhci_parse_frame_interval(udev, endpt_desc);
+		}
+		break;
+
+	default:
+		BUG();
+	}
+
+	return interval;
+}
+
+/*
+ * The "Mult" field in the endpoint context is only set for SuperSpeed isoc eps.
+ * High speed endpoint descriptors can define "the number of additional
+ * transaction opportunities per microframe", but that goes in the Max Burst
+ * endpoint context field.
+ */
+static u32 xhci_get_endpoint_mult(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc,
+	struct usb_ss_ep_comp_descriptor *ss_ep_comp_desc)
+{
+	if (udev->speed < USB_SPEED_SUPER ||
+	    !usb_endpoint_xfer_isoc(endpt_desc))
+		return 0;
+
+	return ss_ep_comp_desc->bmAttributes;
+}
+
+static u32 xhci_get_endpoint_max_burst(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc,
+	struct usb_ss_ep_comp_descriptor *ss_ep_comp_desc)
+{
+	/* Super speed and Plus have max burst in ep companion desc */
+	if (udev->speed >= USB_SPEED_SUPER)
+		return ss_ep_comp_desc->bMaxBurst;
+
+	if (udev->speed == USB_SPEED_HIGH &&
+	    (usb_endpoint_xfer_isoc(endpt_desc) ||
+	     usb_endpoint_xfer_int(endpt_desc)))
+		return usb_endpoint_maxp_mult(endpt_desc) - 1;
+
+	return 0;
+}
+
+/*
+ * Return the maximum endpoint service interval time (ESIT) payload.
+ * Basically, this is the maxpacket size, multiplied by the burst size
+ * and mult size.
+ */
+static u32 xhci_get_max_esit_payload(struct usb_device *udev,
+	struct usb_endpoint_descriptor *endpt_desc,
+	struct usb_ss_ep_comp_descriptor *ss_ep_comp_desc)
+{
+	int max_burst;
+	int max_packet;
+
+	/* Only applies for interrupt or isochronous endpoints */
+	if (usb_endpoint_xfer_control(endpt_desc) ||
+	    usb_endpoint_xfer_bulk(endpt_desc))
+		return 0;
+
+	/* SuperSpeed Isoc ep with less than 48k per esit */
+	if (udev->speed >= USB_SPEED_SUPER)
+		return le16_to_cpu(ss_ep_comp_desc->wBytesPerInterval);
+
+	max_packet = usb_endpoint_maxp(endpt_desc);
+	max_burst = usb_endpoint_maxp_mult(endpt_desc);
+
+	/* A 0 in max burst means 1 transfer per ESIT */
+	return max_packet * max_burst;
+}
+
 /**
  * Issue a configure endpoint command or evaluate context command
  * and wait for it to finish.
@@ -324,6 +506,12 @@ static int xhci_set_configuration(struct usb_device *udev)
 	int slot_id = udev->slot_id;
 	struct xhci_virt_device *virt_dev = ctrl->devs[slot_id];
 	struct usb_interface *ifdesc;
+	u32 max_esit_payload;
+	unsigned int interval;
+	unsigned int mult;
+	unsigned int max_burst;
+	unsigned int avg_trb_len;
+	unsigned int err_count = 0;
 
 	out_ctx = virt_dev->out_ctx;
 	in_ctx = virt_dev->in_ctx;
@@ -357,10 +545,28 @@ static int xhci_set_configuration(struct usb_device *udev)
 	/* filling up ep contexts */
 	for (cur_ep = 0; cur_ep < num_of_ep; cur_ep++) {
 		struct usb_endpoint_descriptor *endpt_desc = NULL;
+		struct usb_ss_ep_comp_descriptor *ss_ep_comp_desc = NULL;
 
 		endpt_desc = &ifdesc->ep_desc[cur_ep];
+		ss_ep_comp_desc = &ifdesc->ss_ep_comp_desc[cur_ep];
 		trb_64 = 0;
 
+		/*
+		 * Get values to fill the endpoint context, mostly from ep
+		 * descriptor. The average TRB buffer lengt for bulk endpoints
+		 * is unclear as we have no clue on scatter gather list entry
+		 * size. For Isoc and Int, set it to max available.
+		 * See xHCI 1.1 spec 4.14.1.1 for details.
+		 */
+		max_esit_payload = xhci_get_max_esit_payload(udev, endpt_desc,
+							     ss_ep_comp_desc);
+		interval = xhci_get_endpoint_interval(udev, endpt_desc);
+		mult = xhci_get_endpoint_mult(udev, endpt_desc,
+					      ss_ep_comp_desc);
+		max_burst = xhci_get_endpoint_max_burst(udev, endpt_desc,
+							ss_ep_comp_desc);
+		avg_trb_len = max_esit_payload;
+
 		ep_index = xhci_get_ep_index(endpt_desc);
 		ep_ctx[ep_index] = xhci_get_ep_ctx(ctrl, in_ctx, ep_index);
 
@@ -372,20 +578,38 @@ static int xhci_set_configuration(struct usb_device *udev)
 		/*NOTE: ep_desc[0] actually represents EP1 and so on */
 		dir = (((endpt_desc->bEndpointAddress) & (0x80)) >> 7);
 		ep_type = (((endpt_desc->bmAttributes) & (0x3)) | (dir << 2));
+
+		ep_ctx[ep_index]->ep_info =
+			cpu_to_le32(EP_MAX_ESIT_PAYLOAD_HI(max_esit_payload) |
+			EP_INTERVAL(interval) | EP_MULT(mult));
+
 		ep_ctx[ep_index]->ep_info2 =
 			cpu_to_le32(ep_type << EP_TYPE_SHIFT);
 		ep_ctx[ep_index]->ep_info2 |=
 			cpu_to_le32(MAX_PACKET
 			(get_unaligned(&endpt_desc->wMaxPacketSize)));
 
+		/* Allow 3 retries for everything but isoc, set CErr = 3 */
+		if (!usb_endpoint_xfer_isoc(endpt_desc))
+			err_count = 3;
 		ep_ctx[ep_index]->ep_info2 |=
-			cpu_to_le32(((0 & MAX_BURST_MASK) << MAX_BURST_SHIFT) |
-			((3 & ERROR_COUNT_MASK) << ERROR_COUNT_SHIFT));
+			cpu_to_le32(MAX_BURST(max_burst) |
+			ERROR_COUNT(err_count));
 
 		trb_64 = (uintptr_t)
 				virt_dev->eps[ep_index].ring->enqueue;
 		ep_ctx[ep_index]->deq = cpu_to_le64(trb_64 |
 				virt_dev->eps[ep_index].ring->cycle_state);
+
+		/*
+		 * xHCI spec 6.2.3:
+		 * 'Average TRB Length' should be 8 for control endpoints.
+		 */
+		if (usb_endpoint_xfer_control(endpt_desc))
+			avg_trb_len = 8;
+		ep_ctx[ep_index]->tx_info =
+			cpu_to_le32(EP_MAX_ESIT_PAYLOAD_LO(max_esit_payload) |
+			EP_AVG_TRB_LENGTH(avg_trb_len));
 	}
 
 	return xhci_configure_endpoints(udev, false);
@@ -546,16 +770,13 @@ int xhci_check_maxpacket(struct usb_device *udev)
 	int max_packet_size;
 	int hw_max_packet_size;
 	int ret = 0;
-	struct usb_interface *ifdesc;
-
-	ifdesc = &udev->config.if_desc[0];
 
 	out_ctx = ctrl->devs[slot_id]->out_ctx;
 	xhci_inval_cache((uintptr_t)out_ctx->bytes, out_ctx->size);
 
 	ep_ctx = xhci_get_ep_ctx(ctrl, out_ctx, ep_index);
 	hw_max_packet_size = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
-	max_packet_size = usb_endpoint_maxp(&ifdesc->ep_desc[0]);
+	max_packet_size = udev->epmaxpacketin[0];
 	if (hw_max_packet_size != max_packet_size) {
 		debug("Max Packet Size for ep 0 changed.\n");
 		debug("Max packet size in usb_device = %d\n", max_packet_size);
@@ -567,7 +788,8 @@ int xhci_check_maxpacket(struct usb_device *udev)
 				ctrl->devs[slot_id]->out_ctx, ep_index);
 		in_ctx = ctrl->devs[slot_id]->in_ctx;
 		ep_ctx = xhci_get_ep_ctx(ctrl, in_ctx, ep_index);
-		ep_ctx->ep_info2 &= cpu_to_le32(~MAX_PACKET_MASK);
+		ep_ctx->ep_info2 &= cpu_to_le32(~((0xffff & MAX_PACKET_MASK)
+						<< MAX_PACKET_SHIFT));
 		ep_ctx->ep_info2 |= cpu_to_le32(MAX_PACKET(max_packet_size));
 
 		/*
@@ -890,11 +1112,18 @@ unknown:
 static int _xhci_submit_int_msg(struct usb_device *udev, unsigned long pipe,
 				void *buffer, int length, int interval)
 {
+	if (usb_pipetype(pipe) != PIPE_INTERRUPT) {
+		printf("non-interrupt pipe (type=%lu)", usb_pipetype(pipe));
+		return -EINVAL;
+	}
+
 	/*
-	 * TODO: Not addressing any interrupt type transfer requests
-	 * Add support for it later.
+	 * xHCI uses normal TRBs for both bulk and interrupt. When the
+	 * interrupt endpoint is to be serviced, the xHC will consume
+	 * (at most) one TD. A TD (comprised of sg list entries) can
+	 * take several service intervals to transmit.
 	 */
-	return -EINVAL;
+	return xhci_bulk_tx(udev, pipe, length, buffer);
 }
 
 /**
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 3377450..ba5f650 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -663,8 +663,9 @@ struct xhci_ep_ctx {
 #define GET_MAX_PACKET(p)	((p) & 0x7ff)
 
 /* tx_info bitmasks */
-#define AVG_TRB_LENGTH_FOR_EP(p)	((p) & 0xffff)
-#define MAX_ESIT_PAYLOAD_FOR_EP(p)	(((p) & 0xffff) << 16)
+#define EP_AVG_TRB_LENGTH(p)		((p) & 0xffff)
+#define EP_MAX_ESIT_PAYLOAD_LO(p)	(((p) & 0xffff) << 16)
+#define EP_MAX_ESIT_PAYLOAD_HI(p)	((((p) >> 16) & 0xff) << 24)
 #define CTX_TO_MAX_ESIT_PAYLOAD(p)	(((p) >> 16) & 0xffff)
 
 /* deq bitmasks */
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 0ad4782..264c971 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -418,6 +418,12 @@ struct __packed usb_class_report_descriptor {
 #define USB_ENDPOINT_XFER_INT		3
 #define USB_ENDPOINT_MAX_ADJUSTABLE	0x80
 
+#define USB_ENDPOINT_MAXP_MASK		0x07ff
+#define USB_EP_MAXP_MULT_SHIFT		11
+#define USB_EP_MAXP_MULT_MASK		(3 << USB_EP_MAXP_MULT_SHIFT)
+#define USB_EP_MAXP_MULT(m)		\
+	(((m) & USB_EP_MAXP_MULT_MASK) >> USB_EP_MAXP_MULT_SHIFT)
+
 /* The USB 3.0 spec redefines bits 5:4 of bmAttributes as interrupt ep type. */
 #define USB_ENDPOINT_INTRTYPE		0x30
 #define USB_ENDPOINT_INTR_PERIODIC	(0 << 4)
@@ -625,6 +631,20 @@ static inline int usb_endpoint_maxp(const struct usb_endpoint_descriptor *epd)
 	return __le16_to_cpu(get_unaligned(&epd->wMaxPacketSize));
 }
 
+/**
+ * usb_endpoint_maxp_mult - get endpoint's transactional opportunities
+ * @epd: endpoint to be checked
+ *
+ * Return @epd's wMaxPacketSize[12:11] + 1
+ */
+static inline int
+usb_endpoint_maxp_mult(const struct usb_endpoint_descriptor *epd)
+{
+	int maxp = __le16_to_cpu(epd->wMaxPacketSize);
+
+	return USB_EP_MAXP_MULT(maxp) + 1;
+}
+
 static inline int usb_endpoint_interrupt_type(
 		const struct usb_endpoint_descriptor *epd)
 {
diff --git a/include/usb.h b/include/usb.h
index 0ddc082..57a7d8d 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -653,6 +653,18 @@ struct usb_bus_priv {
 };
 
 /**
+ * struct usb_emul_platdata - platform data about the USB emulator
+ *
+ * Given a USB emulator (UCLASS_USB_EMUL) 'dev', this is
+ * dev_get_uclass_platdata(dev).
+ *
+ * @port1:	USB emulator device port number on the parent hub
+ */
+struct usb_emul_platdata {
+	int port1;	/* Port number (numbered from 1) */
+};
+
+/**
  * struct dm_usb_ops - USB controller operations
  *
  * This defines the operations supoorted on a USB controller. Common
@@ -976,7 +988,6 @@ int usb_get_max_xfer_size(struct usb_device *dev, size_t *size);
  * the USB emulation uclass about the features of the emulator.
  *
  * @dev:		Emulation device
- * @maxpacketsize:	Maximum packet size (e.g. PACKET_SIZE_64)
  * @strings:		List of USB string descriptors, terminated by a NULL
  *			entry
  * @desc_list:		List of points or USB descriptors, terminated by NULL.
@@ -984,8 +995,8 @@ int usb_get_max_xfer_size(struct usb_device *dev, size_t *size);
  *			and others follow on after that.
  * @return 0 if OK, -ENOSYS if not implemented, other -ve on error
  */
-int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
-			  struct usb_string *strings, void **desc_list);
+int usb_emul_setup_device(struct udevice *dev, struct usb_string *strings,
+			  void **desc_list);
 
 /**
  * usb_emul_control() - Send a control packet to an emulator
@@ -1024,19 +1035,20 @@ int usb_emul_int(struct udevice *emul, struct usb_device *udev,
 /**
  * usb_emul_find() - Find an emulator for a particular device
  *
- * Check @pipe to find a device number on bus @bus and return it.
+ * Check @pipe and @port1 to find a device number on bus @bus and return it.
  *
  * @bus:	USB bus (controller)
  * @pipe:	Describes pipe being used, and includes the device number
+ * @port1:	Describes port number on the parent hub
  * @emulp:	Returns pointer to emulator, or NULL if not found
  * @return 0 if found, -ve on error
  */
-int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp);
+int usb_emul_find(struct udevice *bus, ulong pipe, int port1,
+		  struct udevice **emulp);
 
 /**
  * usb_emul_find_for_dev() - Find an emulator for a particular device
  *
- * @bus:	USB bus (controller)
  * @dev:	USB device to check
  * @emulp:	Returns pointer to emulator, or NULL if not found
  * @return 0 if found, -ve on error
@@ -1044,12 +1056,15 @@ int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp);
 int usb_emul_find_for_dev(struct udevice *dev, struct udevice **emulp);
 
 /**
- * usb_emul_reset() - Reset all emulators ready for use
+ * usb_emul_find_descriptor() - Find a USB descriptor of a particular device
  *
- * Clear out any address information in the emulators and make then ready for
- * a new USB scan
+ * @ptr:	a pointer to a list of USB descriptor pointers
+ * @type:	type of USB descriptor to find
+ * @index:	if @type is USB_DT_CONFIG, this is the configuration value
+ * @return a pointer to the USB descriptor found, NULL if not found
  */
-void usb_emul_reset(struct udevice *dev);
+struct usb_generic_descriptor **usb_emul_find_descriptor(
+		struct usb_generic_descriptor **ptr, int type, int index);
 
 /**
  * usb_show_tree() - show the USB device tree
diff --git a/test/dm/usb.c b/test/dm/usb.c
index b46ae60..4fd249b 100644
--- a/test/dm/usb.c
+++ b/test/dm/usb.c
@@ -99,10 +99,10 @@ static int count_usb_devices(void)
 	return count;
 }
 
-/* test that we can remove an emulated device and it is then not found */
-static int dm_test_usb_remove(struct unit_test_state *uts)
+/* test that no USB devices are found after we stop the stack */
+static int dm_test_usb_stop(struct unit_test_state *uts)
 {
-	struct udevice *dev, *emul;
+	struct udevice *dev;
 
 	/* Scan and check that all devices are present */
 	state_set_skip_delays(true);
@@ -112,164 +112,11 @@ static int dm_test_usb_remove(struct unit_test_state *uts)
 	ut_assertok(uclass_get_device(UCLASS_MASS_STORAGE, 2, &dev));
 	ut_asserteq(6, count_usb_devices());
 	ut_assertok(usb_stop());
-	ut_asserteq(6, count_usb_devices());
-
-	/* Remove the second emulation device */
-	ut_assertok(uclass_find_device_by_name(UCLASS_USB_EMUL, "flash-stick@1",
-					       &dev));
-	ut_assertok(device_unbind(dev));
-
-	/* Rescan - only the first and third should be present */
-	ut_assertok(usb_init());
-	ut_assertok(uclass_get_device(UCLASS_MASS_STORAGE, 0, &dev));
-	ut_assertok(usb_emul_find_for_dev(dev, &emul));
-	ut_asserteq_str("flash-stick@0", emul->name);
-	ut_assertok(uclass_get_device(UCLASS_MASS_STORAGE, 1, &dev));
-	ut_assertok(usb_emul_find_for_dev(dev, &emul));
-	ut_asserteq_str("flash-stick@2", emul->name);
-
-	ut_asserteq(-ENODEV, uclass_get_device(UCLASS_MASS_STORAGE, 2, &dev));
-
-	ut_asserteq(5, count_usb_devices());
-	ut_assertok(usb_stop());
-	ut_asserteq(5, count_usb_devices());
-
-	return 0;
-}
-DM_TEST(dm_test_usb_remove, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
-
-const char usb_tree_base[] =
-"  1  Hub (12 Mb/s, 100mA)\n"
-"  |  sandbox hub 2345\n"
-"  |\n"
-"  |\b+-2  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@0\n"
-"  |  \n"
-"  |\b+-3  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@1\n"
-"  |  \n"
-"  |\b+-4  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@2\n"
-"  |  \n"
-"  |\b+-5  Human Interface (12 Mb/s, 100mA)\n"
-"       sandbox keyboard keyb@3\n"
-"     \n";
-
-/* test that the 'usb tree' command output looks correct */
-static int dm_test_usb_tree(struct unit_test_state *uts)
-{
-	char *data;
-	int len;
-
-	state_set_skip_delays(true);
-	ut_assertok(usb_init());
-	console_record_reset_enable();
-	usb_show_tree();
-	len = membuff_getraw(&gd->console_out, -1, true, &data);
-	if (len)
-		data[len] = '\0';
-	ut_asserteq_str(usb_tree_base, data);
-	ut_assertok(usb_stop());
-
-	return 0;
-}
-DM_TEST(dm_test_usb_tree, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
-
-const char usb_tree_remove[] =
-"  1  Hub (12 Mb/s, 100mA)\n"
-"  |  sandbox hub 2345\n"
-"  |\n"
-"  |\b+-2  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@0\n"
-"  |  \n"
-"  |\b+-3  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@2\n"
-"  |  \n"
-"  |\b+-4  Human Interface (12 Mb/s, 100mA)\n"
-"       sandbox keyboard keyb@3\n"
-"     \n";
-
-/*
- * test that the 'usb tree' command output looks correct when we remove a
- * device
- */
-static int dm_test_usb_tree_remove(struct unit_test_state *uts)
-{
-	struct udevice *dev;
-	char *data;
-	int len;
-
-	/* Remove the second emulation device */
-	ut_assertok(uclass_find_device_by_name(UCLASS_USB_EMUL, "flash-stick@1",
-					       &dev));
-	ut_assertok(device_unbind(dev));
-
-	state_set_skip_delays(true);
-	ut_assertok(usb_init());
-	console_record_reset_enable();
-	usb_show_tree();
-	len = membuff_getraw(&gd->console_out, -1, true, &data);
-	if (len)
-		data[len] = '\0';
-	ut_asserteq_str(usb_tree_remove, data);
-	ut_assertok(usb_stop());
-
-	return 0;
-}
-DM_TEST(dm_test_usb_tree_remove, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
-
-const char usb_tree_reorder[] =
-"  1  Hub (12 Mb/s, 100mA)\n"
-"  |  sandbox hub 2345\n"
-"  |\n"
-"  |\b+-2  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@0\n"
-"  |  \n"
-"  |\b+-3  Mass Storage (12 Mb/s, 100mA)\n"
-"  |    sandbox flash flash-stick@2\n"
-"  |  \n"
-"  |\b+-4  Human Interface (12 Mb/s, 100mA)\n"
-"  |    sandbox keyboard keyb@3\n"
-"  |  \n"
-"  |\b+-5  Mass Storage (12 Mb/s, 100mA)\n"
-"       sandbox flash flash-stick@1\n"
-"     \n";
-
-/*
- * test that the 'usb tree' command output looks correct when we reorder two
- * devices.
- */
-static int dm_test_usb_tree_reorder(struct unit_test_state *uts)
-{
-	struct udevice *dev, *parent;
-	char *data;
-	int len;
-
-	/* Remove the second emulation device */
-	ut_assertok(uclass_find_device_by_name(UCLASS_USB_EMUL, "flash-stick@1",
-					       &dev));
-	parent = dev->parent;
-
-	/* Reorder the devices in the parent list and uclass list */
-	list_del(&dev->sibling_node);
-	list_add_tail(&dev->sibling_node, &parent->child_head);
-
-	list_del(&dev->uclass_node);
-	list_add_tail(&dev->uclass_node, &dev->uclass->dev_head);
-
-	state_set_skip_delays(true);
-	ut_assertok(usb_init());
-	console_record_reset_enable();
-	usb_show_tree();
-	len = membuff_getraw(&gd->console_out, -1, true, &data);
-	if (len)
-		data[len] = '\0';
-	ut_asserteq_str(usb_tree_reorder, data);
-	ut_assertok(usb_stop());
+	ut_asserteq(0, count_usb_devices());
 
 	return 0;
 }
-DM_TEST(dm_test_usb_tree_reorder, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+DM_TEST(dm_test_usb_stop, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
 
 static int dm_test_usb_keyb(struct unit_test_state *uts)
 {