diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 3b53bf2..9af78e8 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -68,6 +68,8 @@
 
 source "drivers/usb/host/Kconfig"
 
+source "drivers/usb/cdns3/Kconfig"
+
 source "drivers/usb/dwc3/Kconfig"
 
 source "drivers/usb/musb/Kconfig"
diff --git a/drivers/usb/cdns3/Kconfig b/drivers/usb/cdns3/Kconfig
new file mode 100644
index 0000000..25c0f10
--- /dev/null
+++ b/drivers/usb/cdns3/Kconfig
@@ -0,0 +1,51 @@
+config USB_CDNS3
+	tristate "Cadence USB3 Dual-Role Controller"
+	depends on USB_HOST || USB_GADGET
+	help
+	  Say Y here if your system has a Cadence USB3 dual-role controller.
+	  It supports: Host-only, and Peripheral-only.
+
+if USB_CDNS3
+
+config USB_CDNS3_GADGET
+	bool "Cadence USB3 device controller"
+	depends on USB_GADGET
+	select USB_GADGET_DUALSPEED
+	help
+	  Say Y here to enable device controller functionality of the
+	  Cadence USBSS-DEV driver.
+
+	  This controller supports FF and HS mode. It doesn't support
+	  LS and SSP mode.
+
+config USB_CDNS3_HOST
+	bool "Cadence USB3 host controller"
+	depends on USB_XHCI_HCD
+	help
+	  Say Y here to enable host controller functionality of the
+	  Cadence driver.
+
+	  Host controller is compliant with XHCI so it will use
+	  standard XHCI driver.
+
+config SPL_USB_CDNS3_GADGET
+	bool "SPL support for Cadence USB3 device controller"
+	depends on SPL_USB_GADGET
+	select USB_GADGET_DUALSPEED
+	help
+	  Say Y here to enable device controller functionality of the
+	  Cadence USBSS-DEV driver in SPL.
+
+	  This controller supports FF and HS mode. It doesn't support
+	  LS and SSP mode.
+
+config SPL_USB_CDNS3_HOST
+	bool "Cadence USB3 host controller"
+	depends on USB_XHCI_HCD && SPL_USB_HOST_SUPPORT
+	help
+	  Say Y here to enable host controller functionality of the
+	  Cadence driver.
+
+	  Host controller is compliant with XHCI so it will use
+	  standard XHCI driver.
+endif
diff --git a/drivers/usb/cdns3/Makefile b/drivers/usb/cdns3/Makefile
new file mode 100644
index 0000000..5254779
--- /dev/null
+++ b/drivers/usb/cdns3/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+
+cdns3-y					:= core.o drd.o
+
+obj-$(CONFIG_USB_CDNS3)			+= cdns3.o
+
+cdns3-$(CONFIG_$(SPL_)USB_CDNS3_GADGET)	+= gadget.o ep0.o
+
+cdns3-$(CONFIG_$(SPL_)USB_CDNS3_HOST)	+= host.o
diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
new file mode 100644
index 0000000..f1e4bb6
--- /dev/null
+++ b/drivers/usb/cdns3/core.c
@@ -0,0 +1,498 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver.
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ * Copyright (C) 2017-2018 NXP
+ * Copyright (C) 2019 Texas Instruments
+ *
+ * Author: Peter Chen <peter.chen@nxp.com>
+ *         Pawel Laszczak <pawell@cadence.com>
+ *         Roger Quadros <rogerq@ti.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <usb.h>
+#include "../host/xhci.h"
+
+#include "core.h"
+#include "host-export.h"
+#include "gadget-export.h"
+#include "drd.h"
+
+static int cdns3_idle_init(struct cdns3 *cdns);
+
+struct cdns3_host_priv {
+	struct xhci_ctrl xhci_ctrl;
+	struct cdns3 cdns;
+};
+
+struct cdns3_gadget_priv {
+	struct cdns3 cdns;
+};
+
+static inline
+struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
+{
+	WARN_ON(!cdns->roles[cdns->role]);
+	return cdns->roles[cdns->role];
+}
+
+static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
+{
+	int ret;
+
+	if (WARN_ON(role > USB_ROLE_DEVICE))
+		return 0;
+
+	mutex_lock(&cdns->mutex);
+	cdns->role = role;
+	mutex_unlock(&cdns->mutex);
+
+	if (!cdns->roles[role])
+		return -ENXIO;
+
+	if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
+		return 0;
+
+	mutex_lock(&cdns->mutex);
+	ret = cdns->roles[role]->start(cdns);
+	if (!ret)
+		cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
+	mutex_unlock(&cdns->mutex);
+
+	return ret;
+}
+
+static void cdns3_role_stop(struct cdns3 *cdns)
+{
+	enum usb_role role = cdns->role;
+
+	if (WARN_ON(role > USB_ROLE_DEVICE))
+		return;
+
+	if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
+		return;
+
+	mutex_lock(&cdns->mutex);
+	cdns->roles[role]->stop(cdns);
+	cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
+	mutex_unlock(&cdns->mutex);
+}
+
+static void cdns3_exit_roles(struct cdns3 *cdns)
+{
+	cdns3_role_stop(cdns);
+	cdns3_drd_exit(cdns);
+}
+
+static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns);
+
+/**
+ * cdns3_core_init_role - initialize role of operation
+ * @cdns: Pointer to cdns3 structure
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+static int cdns3_core_init_role(struct cdns3 *cdns)
+{
+	struct udevice *dev = cdns->dev;
+	enum usb_dr_mode best_dr_mode;
+	enum usb_dr_mode dr_mode;
+	int ret = 0;
+
+	dr_mode = usb_get_dr_mode(dev_of_offset(dev));
+	cdns->role = USB_ROLE_NONE;
+
+	/*
+	 * If driver can't read mode by means of usb_get_dr_mode function then
+	 * chooses mode according with Kernel configuration. This setting
+	 * can be restricted later depending on strap pin configuration.
+	 */
+	if (dr_mode == USB_DR_MODE_UNKNOWN) {
+		if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
+		    IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
+			dr_mode = USB_DR_MODE_OTG;
+		else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
+			dr_mode = USB_DR_MODE_HOST;
+		else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
+			dr_mode = USB_DR_MODE_PERIPHERAL;
+	}
+
+	/*
+	 * At this point cdns->dr_mode contains strap configuration.
+	 * Driver try update this setting considering kernel configuration
+	 */
+	best_dr_mode = cdns->dr_mode;
+
+	ret = cdns3_idle_init(cdns);
+	if (ret)
+		return ret;
+
+	if (dr_mode == USB_DR_MODE_OTG) {
+		best_dr_mode = cdns->dr_mode;
+	} else if (cdns->dr_mode == USB_DR_MODE_OTG) {
+		best_dr_mode = dr_mode;
+	} else if (cdns->dr_mode != dr_mode) {
+		dev_err(dev, "Incorrect DRD configuration\n");
+		return -EINVAL;
+	}
+
+	dr_mode = best_dr_mode;
+
+#if defined(CONFIG_SPL_USB_HOST_SUPPORT) || !defined(CONFIG_SPL_BUILD)
+	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
+		ret = cdns3_host_init(cdns);
+		if (ret) {
+			dev_err(dev, "Host initialization failed with %d\n",
+				ret);
+			goto err;
+		}
+	}
+#endif
+
+#if CONFIG_IS_ENABLED(DM_USB_GADGET)
+	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
+		ret = cdns3_gadget_init(cdns);
+		if (ret) {
+			dev_err(dev, "Device initialization failed with %d\n",
+				ret);
+			goto err;
+		}
+	}
+#endif
+
+	cdns->dr_mode = dr_mode;
+
+	ret = cdns3_drd_update_mode(cdns);
+	if (ret)
+		goto err;
+
+	if (cdns->dr_mode != USB_DR_MODE_OTG) {
+		ret = cdns3_hw_role_switch(cdns);
+		if (ret)
+			goto err;
+	}
+
+	return ret;
+err:
+	cdns3_exit_roles(cdns);
+	return ret;
+}
+
+/**
+ * cdsn3_hw_role_state_machine - role switch state machine based on hw events
+ * @cdns: Pointer to controller structure.
+ *
+ * Returns next role to be entered based on hw events.
+ */
+static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns)
+{
+	enum usb_role role;
+	int id, vbus;
+
+	if (cdns->dr_mode != USB_DR_MODE_OTG)
+		goto not_otg;
+
+	id = cdns3_get_id(cdns);
+	vbus = cdns3_get_vbus(cdns);
+
+	/*
+	 * Role change state machine
+	 * Inputs: ID, VBUS
+	 * Previous state: cdns->role
+	 * Next state: role
+	 */
+	role = cdns->role;
+
+	switch (role) {
+	case USB_ROLE_NONE:
+		/*
+		 * Driver treats USB_ROLE_NONE synonymous to IDLE state from
+		 * controller specification.
+		 */
+		if (!id)
+			role = USB_ROLE_HOST;
+		else if (vbus)
+			role = USB_ROLE_DEVICE;
+		break;
+	case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
+		if (id)
+			role = USB_ROLE_NONE;
+		break;
+	case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
+		if (!vbus)
+			role = USB_ROLE_NONE;
+		break;
+	}
+
+	dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
+
+	return role;
+
+not_otg:
+	if (cdns3_is_host(cdns))
+		role = USB_ROLE_HOST;
+	if (cdns3_is_device(cdns))
+		role = USB_ROLE_DEVICE;
+
+	return role;
+}
+
+static int cdns3_idle_role_start(struct cdns3 *cdns)
+{
+	return 0;
+}
+
+static void cdns3_idle_role_stop(struct cdns3 *cdns)
+{
+	/* Program Lane swap and bring PHY out of RESET */
+	generic_phy_reset(&cdns->usb3_phy);
+}
+
+static int cdns3_idle_init(struct cdns3 *cdns)
+{
+	struct cdns3_role_driver *rdrv;
+
+	rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
+	if (!rdrv)
+		return -ENOMEM;
+
+	rdrv->start = cdns3_idle_role_start;
+	rdrv->stop = cdns3_idle_role_stop;
+	rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
+	rdrv->suspend = NULL;
+	rdrv->resume = NULL;
+	rdrv->name = "idle";
+
+	cdns->roles[USB_ROLE_NONE] = rdrv;
+
+	return 0;
+}
+
+/**
+ * cdns3_hw_role_switch - switch roles based on HW state
+ * @cdns3: controller
+ */
+int cdns3_hw_role_switch(struct cdns3 *cdns)
+{
+	enum usb_role real_role, current_role;
+	int ret = 0;
+
+	/* Do nothing if role based on syfs. */
+	if (cdns->role_override)
+		return 0;
+
+	current_role = cdns->role;
+	real_role = cdsn3_hw_role_state_machine(cdns);
+
+	/* Do nothing if nothing changed */
+	if (current_role == real_role)
+		goto exit;
+
+	cdns3_role_stop(cdns);
+
+	dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
+
+	ret = cdns3_role_start(cdns, real_role);
+	if (ret) {
+		/* Back to current role */
+		dev_err(cdns->dev, "set %d has failed, back to %d\n",
+			real_role, current_role);
+		ret = cdns3_role_start(cdns, current_role);
+		if (ret)
+			dev_err(cdns->dev, "back to %d failed too\n",
+				current_role);
+	}
+exit:
+	return ret;
+}
+
+static int cdns3_probe(struct cdns3 *cdns)
+{
+	struct udevice *dev = cdns->dev;
+	int ret;
+
+	cdns->xhci_regs = dev_remap_addr_name(dev, "xhci");
+	if (!cdns->xhci_regs)
+		return -EINVAL;
+
+	cdns->dev_regs = dev_remap_addr_name(dev, "dev");
+	if (!cdns->dev_regs)
+		return -EINVAL;
+
+	mutex_init(&cdns->mutex);
+
+	ret = generic_phy_get_by_name(dev, "cdns3,usb2-phy", &cdns->usb2_phy);
+	if (ret)
+		dev_warn(dev, "Unable to get USB2 phy (ret %d)\n", ret);
+
+	ret = generic_phy_init(&cdns->usb2_phy);
+	if (ret)
+		return ret;
+
+	ret = generic_phy_get_by_name(dev, "cdns3,usb3-phy", &cdns->usb3_phy);
+	if (ret)
+		dev_warn(dev, "Unable to get USB3 phy (ret %d)\n", ret);
+
+	ret = generic_phy_init(&cdns->usb3_phy);
+	if (ret)
+		return ret;
+
+	ret = generic_phy_power_on(&cdns->usb2_phy);
+	if (ret)
+		return ret;
+
+	ret = generic_phy_power_on(&cdns->usb3_phy);
+	if (ret)
+		return ret;
+
+	ret = cdns3_drd_init(cdns);
+	if (ret)
+		return ret;
+
+	ret = cdns3_core_init_role(cdns);
+	if (ret)
+		return ret;
+
+	dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
+
+	return 0;
+}
+
+static int cdns3_remove(struct cdns3 *cdns)
+{
+	cdns3_exit_roles(cdns);
+	generic_phy_power_off(&cdns->usb2_phy);
+	generic_phy_power_off(&cdns->usb3_phy);
+	generic_phy_exit(&cdns->usb2_phy);
+	generic_phy_exit(&cdns->usb3_phy);
+	return 0;
+}
+
+static const struct udevice_id cdns3_ids[] = {
+	{ .compatible = "cdns,usb3" },
+	{ },
+};
+
+int cdns3_bind(struct udevice *parent)
+{
+	int from = dev_of_offset(parent);
+	const void *fdt = gd->fdt_blob;
+	enum usb_dr_mode dr_mode;
+	struct udevice *dev;
+	const char *driver;
+	const char *name;
+	int node;
+	int ret;
+
+	node = fdt_node_offset_by_compatible(fdt, from, "cdns,usb3");
+	if (node < 0) {
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	name = fdt_get_name(fdt, node, NULL);
+	dr_mode = usb_get_dr_mode(node);
+
+	switch (dr_mode) {
+#if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
+	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
+	case USB_DR_MODE_HOST:
+		debug("%s: dr_mode: HOST\n", __func__);
+		driver = "cdns-usb3-host";
+		break;
+#endif
+#if CONFIG_IS_ENABLED(DM_USB_GADGET)
+	case USB_DR_MODE_PERIPHERAL:
+		debug("%s: dr_mode: PERIPHERAL\n", __func__);
+		driver = "cdns-usb3-peripheral";
+		break;
+#endif
+	default:
+		printf("%s: unsupported dr_mode\n", __func__);
+		ret = -ENODEV;
+		goto fail;
+	};
+
+	ret = device_bind_driver_to_node(parent, driver, name,
+					 offset_to_ofnode(node), &dev);
+	if (ret) {
+		printf("%s: not able to bind usb device mode\n",
+		       __func__);
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	/* do not return an error: failing to bind would hang the board */
+	return 0;
+}
+
+#if CONFIG_IS_ENABLED(DM_USB_GADGET)
+static int cdns3_gadget_probe(struct udevice *dev)
+{
+	struct cdns3_gadget_priv *priv = dev_get_priv(dev);
+	struct cdns3 *cdns = &priv->cdns;
+
+	cdns->dev = dev;
+
+	return cdns3_probe(cdns);
+}
+
+static int cdns3_gadget_remove(struct udevice *dev)
+{
+	struct cdns3_gadget_priv *priv = dev_get_priv(dev);
+	struct cdns3 *cdns = &priv->cdns;
+
+	return cdns3_remove(cdns);
+}
+
+U_BOOT_DRIVER(cdns_usb3_peripheral) = {
+	.name	= "cdns-usb3-peripheral",
+	.id	= UCLASS_USB_GADGET_GENERIC,
+	.of_match = cdns3_ids,
+	.probe = cdns3_gadget_probe,
+	.remove = cdns3_gadget_remove,
+	.priv_auto_alloc_size = sizeof(struct cdns3_gadget_priv),
+	.flags = DM_FLAG_ALLOC_PRIV_DMA,
+};
+#endif
+
+#if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
+	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
+static int cdns3_host_probe(struct udevice *dev)
+{
+	struct cdns3_host_priv *priv = dev_get_priv(dev);
+	struct cdns3 *cdns = &priv->cdns;
+
+	cdns->dev = dev;
+
+	return cdns3_probe(cdns);
+}
+
+static int cdns3_host_remove(struct udevice *dev)
+{
+	struct cdns3_host_priv *priv = dev_get_priv(dev);
+	struct cdns3 *cdns = &priv->cdns;
+
+	return cdns3_remove(cdns);
+}
+
+U_BOOT_DRIVER(cdns_usb3_host) = {
+	.name	= "cdns-usb3-host",
+	.id	= UCLASS_USB,
+	.of_match = cdns3_ids,
+	.probe = cdns3_host_probe,
+	.remove = cdns3_host_remove,
+	.priv_auto_alloc_size = sizeof(struct cdns3_host_priv),
+	.ops = &xhci_usb_ops,
+	.flags = DM_FLAG_ALLOC_PRIV_DMA,
+};
+#endif
diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h
new file mode 100644
index 0000000..0668d64
--- /dev/null
+++ b/drivers/usb/cdns3/core.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Cadence USBSS DRD Header File.
+ *
+ * Copyright (C) 2017-2018 NXP
+ * Copyright (C) 2018-2019 Cadence.
+ *
+ * Authors: Peter Chen <peter.chen@nxp.com>
+ *          Pawel Laszczak <pawell@cadence.com>
+ */
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <linux/usb/otg.h>
+#include <generic-phy.h>
+
+#ifndef __LINUX_CDNS3_CORE_H
+#define __LINUX_CDNS3_CORE_H
+
+enum usb_role {
+	USB_ROLE_NONE,
+	USB_ROLE_HOST,
+	USB_ROLE_DEVICE,
+};
+
+struct cdns3;
+
+/**
+ * struct cdns3_role_driver - host/gadget role driver
+ * @start: start this role
+ * @stop: stop this role
+ * @suspend: suspend callback for this role
+ * @resume: resume callback for this role
+ * @irq: irq handler for this role
+ * @name: role name string (host/gadget)
+ * @state: current state
+ */
+struct cdns3_role_driver {
+	int (*start)(struct cdns3 *cdns);
+	void (*stop)(struct cdns3 *cdns);
+	int (*suspend)(struct cdns3 *cdns, bool do_wakeup);
+	int (*resume)(struct cdns3 *cdns, bool hibernated);
+	const char *name;
+#define CDNS3_ROLE_STATE_INACTIVE	0
+#define CDNS3_ROLE_STATE_ACTIVE		1
+	int state;
+};
+
+#define CDNS3_XHCI_RESOURCES_NUM	2
+/**
+ * struct cdns3 - Representation of Cadence USB3 DRD controller.
+ * @dev: pointer to Cadence device struct
+ * @xhci_regs: pointer to base of xhci registers
+ * @dev_regs: pointer to base of dev registers
+ * @otg_v0_regs: pointer to base of v0 otg registers
+ * @otg_v1_regs: pointer to base of v1 otg registers
+ * @otg_regs: pointer to base of otg registers
+ * @otg_irq: irq number for otg controller
+ * @dev_irq: irq number for device controller
+ * @roles: array of supported roles for this controller
+ * @role: current role
+ * @host_dev: the child host device pointer for cdns3 core
+ * @gadget_dev: the child gadget device pointer for cdns3 core
+ * @usb2_phy: pointer to USB2 PHY
+ * @usb3_phy: pointer to USB3 PHY
+ * @mutex: the mutex for concurrent code at driver
+ * @dr_mode: supported mode of operation it can be only Host, only Device
+ *           or OTG mode that allow to switch between Device and Host mode.
+ *           This field based on firmware setting, kernel configuration
+ *           and hardware configuration.
+ * @role_sw: pointer to role switch object.
+ * @role_override: set 1 if role rely on SW.
+ */
+struct cdns3 {
+	struct udevice			*dev;
+	void __iomem			*xhci_regs;
+	struct cdns3_usb_regs __iomem	*dev_regs;
+
+	struct cdns3_otg_legacy_regs	*otg_v0_regs;
+	struct cdns3_otg_regs		*otg_v1_regs;
+	struct cdns3_otg_common_regs	*otg_regs;
+#define CDNS3_CONTROLLER_V0	0
+#define CDNS3_CONTROLLER_V1	1
+	u32				version;
+
+	int				otg_irq;
+	int				dev_irq;
+	struct cdns3_role_driver	*roles[USB_ROLE_DEVICE + 1];
+	enum usb_role			role;
+	struct cdns3_device		*gadget_dev;
+	struct phy			usb2_phy;
+	struct phy			usb3_phy;
+	/* mutext used in workqueue*/
+	struct mutex			mutex;
+	enum usb_dr_mode		dr_mode;
+	int				role_override;
+};
+
+int cdns3_hw_role_switch(struct cdns3 *cdns);
+
+/**
+ * cdns3_bind - generic bind function
+ * @parent - pointer to parent udevice of which cdns3 USB controller
+ *           node is child of
+ *
+ * return 0 on success, negative errno otherwise
+ */
+int cdns3_bind(struct udevice *dev);
+#endif /* __LINUX_CDNS3_CORE_H */
diff --git a/drivers/usb/cdns3/debug.h b/drivers/usb/cdns3/debug.h
new file mode 100644
index 0000000..0b4673a
--- /dev/null
+++ b/drivers/usb/cdns3/debug.h
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Cadence USBSS DRD Driver.
+ * Debug header file.
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ */
+#ifndef __LINUX_CDNS3_DEBUG
+#define __LINUX_CDNS3_DEBUG
+
+#include "core.h"
+#include "gadget.h"
+
+static inline char *cdns3_decode_usb_irq(char *str,
+					 enum usb_device_speed speed,
+					 u32 usb_ists)
+{
+	int ret;
+
+	ret = sprintf(str, "IRQ %08x = ", usb_ists);
+
+	if (usb_ists & (USB_ISTS_CON2I | USB_ISTS_CONI)) {
+		ret += sprintf(str + ret, "Connection %s\n",
+			       usb_speed_string(speed));
+	}
+	if (usb_ists & USB_ISTS_DIS2I || usb_ists & USB_ISTS_DISI)
+		ret += sprintf(str + ret, "Disconnection ");
+	if (usb_ists & USB_ISTS_L2ENTI)
+		ret += sprintf(str + ret, "suspended ");
+	if (usb_ists & USB_ISTS_L1ENTI)
+		ret += sprintf(str + ret, "L1 enter ");
+	if (usb_ists & USB_ISTS_L1EXTI)
+		ret += sprintf(str + ret, "L1 exit ");
+	if (usb_ists & USB_ISTS_L2ENTI)
+		ret += sprintf(str + ret, "L2 enter ");
+	if (usb_ists & USB_ISTS_L2EXTI)
+		ret += sprintf(str + ret, "L2 exit ");
+	if (usb_ists & USB_ISTS_U3EXTI)
+		ret += sprintf(str + ret, "U3 exit ");
+	if (usb_ists & USB_ISTS_UWRESI)
+		ret += sprintf(str + ret, "Warm Reset ");
+	if (usb_ists & USB_ISTS_UHRESI)
+		ret += sprintf(str + ret, "Hot Reset ");
+	if (usb_ists & USB_ISTS_U2RESI)
+		ret += sprintf(str + ret, "Reset");
+
+	return str;
+}
+
+static inline  char *cdns3_decode_ep_irq(char *str,
+					 u32 ep_sts,
+					 const char *ep_name)
+{
+	int ret;
+
+	ret = sprintf(str, "IRQ for %s: %08x ", ep_name, ep_sts);
+
+	if (ep_sts & EP_STS_SETUP)
+		ret += sprintf(str + ret, "SETUP ");
+	if (ep_sts & EP_STS_IOC)
+		ret += sprintf(str + ret, "IOC ");
+	if (ep_sts & EP_STS_ISP)
+		ret += sprintf(str + ret, "ISP ");
+	if (ep_sts & EP_STS_DESCMIS)
+		ret += sprintf(str + ret, "DESCMIS ");
+	if (ep_sts & EP_STS_STREAMR)
+		ret += sprintf(str + ret, "STREAMR ");
+	if (ep_sts & EP_STS_MD_EXIT)
+		ret += sprintf(str + ret, "MD_EXIT ");
+	if (ep_sts & EP_STS_TRBERR)
+		ret += sprintf(str + ret, "TRBERR ");
+	if (ep_sts & EP_STS_NRDY)
+		ret += sprintf(str + ret, "NRDY ");
+	if (ep_sts & EP_STS_PRIME)
+		ret += sprintf(str + ret, "PRIME ");
+	if (ep_sts & EP_STS_SIDERR)
+		ret += sprintf(str + ret, "SIDERRT ");
+	if (ep_sts & EP_STS_OUTSMM)
+		ret += sprintf(str + ret, "OUTSMM ");
+	if (ep_sts & EP_STS_ISOERR)
+		ret += sprintf(str + ret, "ISOERR ");
+	if (ep_sts & EP_STS_IOT)
+		ret += sprintf(str + ret, "IOT ");
+
+	return str;
+}
+
+static inline char *cdns3_decode_epx_irq(char *str,
+					 char *ep_name,
+					 u32 ep_sts)
+{
+	return cdns3_decode_ep_irq(str, ep_sts, ep_name);
+}
+
+static inline char *cdns3_decode_ep0_irq(char *str,
+					 int dir,
+					 u32 ep_sts)
+{
+	return cdns3_decode_ep_irq(str, ep_sts,
+				   dir ? "ep0IN" : "ep0OUT");
+}
+
+/**
+ * Debug a transfer ring.
+ *
+ * Prints out all TRBs in the endpoint ring, even those after the Link TRB.
+ *.
+ */
+static inline char *cdns3_dbg_ring(struct cdns3_endpoint *priv_ep,
+				   struct cdns3_trb *ring, char *str)
+{
+	dma_addr_t addr = priv_ep->trb_pool_dma;
+	struct cdns3_trb *trb;
+	int trb_per_sector;
+	int ret = 0;
+	int i;
+
+	trb_per_sector = GET_TRBS_PER_SEGMENT(priv_ep->type);
+
+	trb = &priv_ep->trb_pool[priv_ep->dequeue];
+	ret += sprintf(str + ret, "\n\t\tRing contents for %s:", priv_ep->name);
+
+	ret += sprintf(str + ret,
+		       "\n\t\tRing deq index: %d, trb: %p (virt), 0x%llx (dma)\n",
+		       priv_ep->dequeue, trb,
+		       (unsigned long long)cdns3_trb_virt_to_dma(priv_ep, trb));
+
+	trb = &priv_ep->trb_pool[priv_ep->enqueue];
+	ret += sprintf(str + ret,
+		       "\t\tRing enq index: %d, trb: %p (virt), 0x%llx (dma)\n",
+		       priv_ep->enqueue, trb,
+		       (unsigned long long)cdns3_trb_virt_to_dma(priv_ep, trb));
+
+	ret += sprintf(str + ret,
+		       "\t\tfree trbs: %d, CCS=%d, PCS=%d\n",
+		       priv_ep->free_trbs, priv_ep->ccs, priv_ep->pcs);
+
+	if (trb_per_sector > TRBS_PER_SEGMENT)
+		trb_per_sector = TRBS_PER_SEGMENT;
+
+	if (trb_per_sector > TRBS_PER_SEGMENT) {
+		sprintf(str + ret, "\t\tTo big transfer ring %d\n",
+			trb_per_sector);
+		return str;
+	}
+
+	for (i = 0; i < trb_per_sector; ++i) {
+		trb = &ring[i];
+		ret += sprintf(str + ret,
+			"\t\t@%pad %08x %08x %08x\n", &addr,
+			le32_to_cpu(trb->buffer),
+			le32_to_cpu(trb->length),
+			le32_to_cpu(trb->control));
+		addr += sizeof(*trb);
+	}
+
+	return str;
+}
+
+#endif /*__LINUX_CDNS3_DEBUG*/
diff --git a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c
new file mode 100644
index 0000000..13eb489
--- /dev/null
+++ b/drivers/usb/cdns3/drd.c
@@ -0,0 +1,301 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver.
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ * Copyright (C) 2019 Texas Instruments
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *         Roger Quadros <rogerq@ti.com>
+ *
+ *
+ */
+#include <dm.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/usb/otg.h>
+
+#include "gadget.h"
+#include "drd.h"
+#include "core.h"
+
+#define readl_poll_timeout_atomic readl_poll_timeout
+#define usleep_range(a, b) udelay((b))
+/**
+ * cdns3_set_mode - change mode of OTG Core
+ * @cdns: pointer to context structure
+ * @mode: selected mode from cdns_role
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+int cdns3_set_mode(struct cdns3 *cdns, enum usb_dr_mode mode)
+{
+	int ret = 0;
+	u32 reg;
+
+	switch (mode) {
+	case USB_DR_MODE_PERIPHERAL:
+		break;
+	case USB_DR_MODE_HOST:
+		break;
+	case USB_DR_MODE_OTG:
+		dev_dbg(cdns->dev, "Set controller to OTG mode\n");
+		if (cdns->version == CDNS3_CONTROLLER_V1) {
+			reg = readl(&cdns->otg_v1_regs->override);
+			reg |= OVERRIDE_IDPULLUP;
+			writel(reg, &cdns->otg_v1_regs->override);
+		} else {
+			reg = readl(&cdns->otg_v0_regs->ctrl1);
+			reg |= OVERRIDE_IDPULLUP_V0;
+			writel(reg, &cdns->otg_v0_regs->ctrl1);
+		}
+
+		/*
+		 * Hardware specification says: "ID_VALUE must be valid within
+		 * 50ms after idpullup is set to '1" so driver must wait
+		 * 50ms before reading this pin.
+		 */
+		usleep_range(50000, 60000);
+		break;
+	default:
+		dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+int cdns3_get_id(struct cdns3 *cdns)
+{
+	int id;
+
+	id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
+	dev_dbg(cdns->dev, "OTG ID: %d", id);
+
+	return id;
+}
+
+int cdns3_get_vbus(struct cdns3 *cdns)
+{
+	int vbus;
+
+	vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
+	dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
+
+	return vbus;
+}
+
+int cdns3_is_host(struct cdns3 *cdns)
+{
+	if (cdns->dr_mode == USB_DR_MODE_HOST)
+		return 1;
+	else if (!cdns3_get_id(cdns))
+		return 1;
+
+	return 0;
+}
+
+int cdns3_is_device(struct cdns3 *cdns)
+{
+	if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
+		return 1;
+	else if (cdns->dr_mode == USB_DR_MODE_OTG)
+		if (cdns3_get_id(cdns))
+			return 1;
+
+	return 0;
+}
+
+/**
+ * cdns3_drd_switch_host - start/stop host
+ * @cdns: Pointer to controller context structure
+ * @on: 1 for start, 0 for stop
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+int cdns3_drd_switch_host(struct cdns3 *cdns, int on)
+{
+	int ret, val;
+	u32 reg = OTGCMD_OTG_DIS;
+
+	/* switch OTG core */
+	if (on) {
+		writel(OTGCMD_HOST_BUS_REQ | reg, &cdns->otg_regs->cmd);
+
+		dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
+		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
+						val & OTGSTS_XHCI_READY,
+						100000);
+		if (ret) {
+			dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
+			return ret;
+		}
+	} else {
+		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
+		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
+		       &cdns->otg_regs->cmd);
+		/* Waiting till H_IDLE state.*/
+		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
+					  !(val & OTGSTATE_HOST_STATE_MASK),
+					  2000000);
+	}
+
+	return 0;
+}
+
+/**
+ * cdns3_drd_switch_gadget - start/stop gadget
+ * @cdns: Pointer to controller context structure
+ * @on: 1 for start, 0 for stop
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on)
+{
+	int ret, val;
+	u32 reg = OTGCMD_OTG_DIS;
+
+	/* switch OTG core */
+	if (on) {
+		writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
+
+		dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
+
+		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
+						val & OTGSTS_DEV_READY,
+						100000);
+		if (ret) {
+			dev_err(cdns->dev, "timeout waiting for dev_ready\n");
+			return ret;
+		}
+	} else {
+		/*
+		 * driver should wait at least 10us after disabling Device
+		 * before turning-off Device (DEV_BUS_DROP)
+		 */
+		usleep_range(20, 30);
+		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
+		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
+		       &cdns->otg_regs->cmd);
+		/* Waiting till DEV_IDLE state.*/
+		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
+					  !(val & OTGSTATE_DEV_STATE_MASK),
+					  2000000);
+	}
+
+	return 0;
+}
+
+/**
+ * cdns3_init_otg_mode - initialize drd controller
+ * @cdns: Pointer to controller context structure
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+static int cdns3_init_otg_mode(struct cdns3 *cdns)
+{
+	int ret = 0;
+
+	/* clear all interrupts */
+	writel(~0, &cdns->otg_regs->ivect);
+
+	ret = cdns3_set_mode(cdns, USB_DR_MODE_OTG);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
+/**
+ * cdns3_drd_update_mode - initialize mode of operation
+ * @cdns: Pointer to controller context structure
+ *
+ * Returns 0 on success otherwise negative errno
+ */
+int cdns3_drd_update_mode(struct cdns3 *cdns)
+{
+	int ret = 0;
+
+	switch (cdns->dr_mode) {
+	case USB_DR_MODE_PERIPHERAL:
+		ret = cdns3_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
+		break;
+	case USB_DR_MODE_HOST:
+		ret = cdns3_set_mode(cdns, USB_DR_MODE_HOST);
+		break;
+	case USB_DR_MODE_OTG:
+		ret = cdns3_init_otg_mode(cdns);
+		break;
+	default:
+		dev_err(cdns->dev, "Unsupported mode of operation %d\n",
+			cdns->dr_mode);
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+int cdns3_drd_init(struct cdns3 *cdns)
+{
+	void __iomem *regs;
+	int ret = 0;
+	u32 state;
+
+	regs = dev_remap_addr_name(cdns->dev, "otg");
+	if (!regs)
+		return -EINVAL;
+
+	/* Detection of DRD version. Controller has been released
+	 * in two versions. Both are similar, but they have same changes
+	 * in register maps.
+	 * The first register in old version is command register and it's read
+	 * only, so driver should read 0 from it. On the other hand, in v1
+	 * the first register contains device ID number which is not set to 0.
+	 * Driver uses this fact to detect the proper version of
+	 * controller.
+	 */
+	cdns->otg_v0_regs = regs;
+	if (!readl(&cdns->otg_v0_regs->cmd)) {
+		cdns->version  = CDNS3_CONTROLLER_V0;
+		cdns->otg_v1_regs = NULL;
+		cdns->otg_regs = regs;
+		writel(1, &cdns->otg_v0_regs->simulate);
+		dev_info(cdns->dev, "DRD version v0 (%08x)\n",
+			 readl(&cdns->otg_v0_regs->version));
+	} else {
+		cdns->otg_v0_regs = NULL;
+		cdns->otg_v1_regs = regs;
+		cdns->otg_regs = (void *)&cdns->otg_v1_regs->cmd;
+		cdns->version  = CDNS3_CONTROLLER_V1;
+		writel(1, &cdns->otg_v1_regs->simulate);
+		dev_info(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
+			 readl(&cdns->otg_v1_regs->did),
+			 readl(&cdns->otg_v1_regs->rid));
+	}
+
+	state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
+
+	/* Update dr_mode according to STRAP configuration. */
+	cdns->dr_mode = USB_DR_MODE_OTG;
+	if (state == OTGSTS_STRAP_HOST) {
+		dev_dbg(cdns->dev, "Controller strapped to HOST\n");
+		cdns->dr_mode = USB_DR_MODE_HOST;
+	} else if (state == OTGSTS_STRAP_GADGET) {
+		dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
+		cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
+	}
+
+	state = readl(&cdns->otg_regs->sts);
+	if (OTGSTS_OTG_NRDY(state) != 0) {
+		dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
+		return -ENODEV;
+	}
+
+	return ret;
+}
+
+int cdns3_drd_exit(struct cdns3 *cdns)
+{
+	return 0;
+}
diff --git a/drivers/usb/cdns3/drd.h b/drivers/usb/cdns3/drd.h
new file mode 100644
index 0000000..815b93f
--- /dev/null
+++ b/drivers/usb/cdns3/drd.h
@@ -0,0 +1,166 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Cadence USB3 DRD header file.
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ */
+#ifndef __LINUX_CDNS3_DRD
+#define __LINUX_CDNS3_DRD
+
+#include <linux/types.h>
+#include <linux/usb/otg.h>
+#include "core.h"
+
+/*  DRD register interface for version v1. */
+struct cdns3_otg_regs {
+	__le32 did;
+	__le32 rid;
+	__le32 capabilities;
+	__le32 reserved1;
+	__le32 cmd;
+	__le32 sts;
+	__le32 state;
+	__le32 reserved2;
+	__le32 ien;
+	__le32 ivect;
+	__le32 refclk;
+	__le32 tmr;
+	__le32 reserved3[4];
+	__le32 simulate;
+	__le32 override;
+	__le32 susp_ctrl;
+	__le32 reserved4;
+	__le32 anasts;
+	__le32 adp_ramp_time;
+	__le32 ctrl1;
+	__le32 ctrl2;
+};
+
+/*  DRD register interface for version v0. */
+struct cdns3_otg_legacy_regs {
+	__le32 cmd;
+	__le32 sts;
+	__le32 state;
+	__le32 refclk;
+	__le32 ien;
+	__le32 ivect;
+	__le32 reserved1[3];
+	__le32 tmr;
+	__le32 reserved2[2];
+	__le32 version;
+	__le32 capabilities;
+	__le32 reserved3[2];
+	__le32 simulate;
+	__le32 reserved4[5];
+	__le32 ctrl1;
+};
+
+/*
+ * Common registers interface for both version of DRD.
+ */
+struct cdns3_otg_common_regs {
+	__le32 cmd;
+	__le32 sts;
+	__le32 state;
+	__le32 different1;
+	__le32 ien;
+	__le32 ivect;
+};
+
+/* CDNS_RID - bitmasks */
+#define CDNS_RID(p)			((p) & GENMASK(15, 0))
+
+/* CDNS_VID - bitmasks */
+#define CDNS_DID(p)			((p) & GENMASK(31, 0))
+
+/* OTGCMD - bitmasks */
+/* "Request the bus for Device mode. */
+#define OTGCMD_DEV_BUS_REQ		BIT(0)
+/* Request the bus for Host mode */
+#define OTGCMD_HOST_BUS_REQ		BIT(1)
+/* Enable OTG mode. */
+#define OTGCMD_OTG_EN			BIT(2)
+/* Disable OTG mode */
+#define OTGCMD_OTG_DIS			BIT(3)
+/*"Configure OTG as A-Device. */
+#define OTGCMD_A_DEV_EN			BIT(4)
+/*"Configure OTG as A-Device. */
+#define OTGCMD_A_DEV_DIS		BIT(5)
+/* Drop the bus for Device mod	e. */
+#define OTGCMD_DEV_BUS_DROP		BIT(8)
+/* Drop the bus for Host mode*/
+#define OTGCMD_HOST_BUS_DROP		BIT(9)
+/* Power Down USBSS-DEV. */
+#define OTGCMD_DEV_POWER_OFF		BIT(11)
+/* Power Down CDNSXHCI. */
+#define OTGCMD_HOST_POWER_OFF		BIT(12)
+
+/* OTGIEN - bitmasks */
+/* ID change interrupt enable */
+#define OTGIEN_ID_CHANGE_INT		BIT(0)
+/* Vbusvalid fall detected interrupt enable.*/
+#define OTGIEN_VBUSVALID_RISE_INT	BIT(4)
+/* Vbusvalid fall detected interrupt enable */
+#define OTGIEN_VBUSVALID_FALL_INT	BIT(5)
+
+/* OTGSTS - bitmasks */
+/*
+ * Current value of the ID pin. It is only valid when idpullup in
+ *  OTGCTRL1_TYPE register is set to '1'.
+ */
+#define OTGSTS_ID_VALUE			BIT(0)
+/* Current value of the vbus_valid */
+#define OTGSTS_VBUS_VALID		BIT(1)
+/* Current value of the b_sess_vld */
+#define OTGSTS_SESSION_VALID		BIT(2)
+/*Device mode is active*/
+#define OTGSTS_DEV_ACTIVE		BIT(3)
+/* Host mode is active. */
+#define OTGSTS_HOST_ACTIVE		BIT(4)
+/* OTG Controller not ready. */
+#define OTGSTS_OTG_NRDY_MASK		BIT(11)
+#define OTGSTS_OTG_NRDY(p)		((p) & OTGSTS_OTG_NRDY_MASK)
+/*
+ * Value of the strap pins.
+ * 000 - no default configuration
+ * 010 - Controller initiall configured as Host
+ * 100 - Controller initially configured as Device
+ */
+#define OTGSTS_STRAP(p)			(((p) & GENMASK(14, 12)) >> 12)
+#define OTGSTS_STRAP_NO_DEFAULT_CFG	0x00
+#define OTGSTS_STRAP_HOST_OTG		0x01
+#define OTGSTS_STRAP_HOST		0x02
+#define OTGSTS_STRAP_GADGET		0x04
+/* Host mode is turned on. */
+#define OTGSTS_XHCI_READY		BIT(26)
+/* "Device mode is turned on .*/
+#define OTGSTS_DEV_READY		BIT(27)
+
+/* OTGSTATE- bitmasks */
+#define OTGSTATE_DEV_STATE_MASK		GENMASK(2, 0)
+#define OTGSTATE_HOST_STATE_MASK	GENMASK(5, 3)
+#define OTGSTATE_HOST_STATE_IDLE	0x0
+#define OTGSTATE_HOST_STATE_VBUS_FALL	0x7
+#define OTGSTATE_HOST_STATE(p)		(((p) & OTGSTATE_HOST_STATE_MASK) >> 3)
+
+/* OTGREFCLK - bitmasks */
+#define OTGREFCLK_STB_CLK_SWITCH_EN	BIT(31)
+
+/* OVERRIDE - bitmasks */
+#define OVERRIDE_IDPULLUP		BIT(0)
+/* Only for CDNS3_CONTROLLER_V0 version */
+#define OVERRIDE_IDPULLUP_V0		BIT(24)
+
+int cdns3_is_host(struct cdns3 *cdns);
+int cdns3_is_device(struct cdns3 *cdns);
+int cdns3_get_id(struct cdns3 *cdns);
+int cdns3_get_vbus(struct cdns3 *cdns);
+int cdns3_drd_init(struct cdns3 *cdns);
+int cdns3_drd_exit(struct cdns3 *cdns);
+int cdns3_drd_update_mode(struct cdns3 *cdns);
+int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on);
+int cdns3_drd_switch_host(struct cdns3 *cdns, int on);
+
+#endif /* __LINUX_CDNS3_DRD */
diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
new file mode 100644
index 0000000..1903f61
--- /dev/null
+++ b/drivers/usb/cdns3/ep0.c
@@ -0,0 +1,910 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - gadget side.
+ *
+ * Copyright (C) 2018 Cadence Design Systems.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Pawel Jez <pjez@cadence.com>,
+ *          Pawel Laszczak <pawell@cadence.com>
+ *          Peter Chen <peter.chen@nxp.com>
+ */
+
+#include <linux/usb/composite.h>
+#include <linux/iopoll.h>
+
+#include "gadget.h"
+#include "trace.h"
+
+#define readl_poll_timeout_atomic readl_poll_timeout
+#define usleep_range(a, b) udelay((b))
+
+static struct usb_endpoint_descriptor cdns3_gadget_ep0_desc = {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+	.bmAttributes =	USB_ENDPOINT_XFER_CONTROL,
+};
+
+/**
+ * cdns3_ep0_run_transfer - Do transfer on default endpoint hardware
+ * @priv_dev: extended gadget object
+ * @dma_addr: physical address where data is/will be stored
+ * @length: data length
+ * @erdy: set it to 1 when ERDY packet should be sent -
+ *        exit from flow control state
+ */
+static void cdns3_ep0_run_transfer(struct cdns3_device *priv_dev,
+				   dma_addr_t dma_addr,
+				   unsigned int length, int erdy, int zlp)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
+
+	priv_ep->trb_pool[0].buffer = TRB_BUFFER(dma_addr);
+	priv_ep->trb_pool[0].length = TRB_LEN(length);
+
+	if (zlp) {
+		priv_ep->trb_pool[0].control = TRB_CYCLE | TRB_TYPE(TRB_NORMAL);
+		priv_ep->trb_pool[1].buffer = TRB_BUFFER(dma_addr);
+		priv_ep->trb_pool[1].length = TRB_LEN(0);
+		priv_ep->trb_pool[1].control = TRB_CYCLE | TRB_IOC |
+		    TRB_TYPE(TRB_NORMAL);
+	} else {
+		priv_ep->trb_pool[0].control = TRB_CYCLE | TRB_IOC |
+		    TRB_TYPE(TRB_NORMAL);
+		priv_ep->trb_pool[1].control = 0;
+	}
+
+	/* Flush both TRBs */
+	flush_dcache_range((unsigned long)priv_ep->trb_pool,
+			   (unsigned long)priv_ep->trb_pool +
+			   ROUND(sizeof(struct cdns3_trb) * 2,
+				 CONFIG_SYS_CACHELINE_SIZE));
+
+	trace_cdns3_prepare_trb(priv_ep, priv_ep->trb_pool);
+
+	cdns3_select_ep(priv_dev, priv_dev->ep0_data_dir);
+
+	writel(EP_STS_TRBERR, &regs->ep_sts);
+	writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma), &regs->ep_traddr);
+	trace_cdns3_doorbell_ep0(priv_dev->ep0_data_dir ? "ep0in" : "ep0out",
+				 readl(&regs->ep_traddr));
+
+	/* TRB should be prepared before starting transfer. */
+	writel(EP_CMD_DRDY, &regs->ep_cmd);
+
+	/* Resume controller before arming transfer. */
+	__cdns3_gadget_wakeup(priv_dev);
+
+	if (erdy)
+		writel(EP_CMD_ERDY, &priv_dev->regs->ep_cmd);
+}
+
+/**
+ * cdns3_ep0_delegate_req - Returns status of handling setup packet
+ * Setup is handled by gadget driver
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns zero on success or negative value on failure
+ */
+static int cdns3_ep0_delegate_req(struct cdns3_device *priv_dev,
+				  struct usb_ctrlrequest *ctrl_req)
+{
+	int ret;
+
+	spin_unlock(&priv_dev->lock);
+	priv_dev->setup_pending = 1;
+	ret = priv_dev->gadget_driver->setup(&priv_dev->gadget, ctrl_req);
+	priv_dev->setup_pending = 0;
+	spin_lock(&priv_dev->lock);
+	return ret;
+}
+
+static void cdns3_prepare_setup_packet(struct cdns3_device *priv_dev)
+{
+	priv_dev->ep0_data_dir = 0;
+	priv_dev->ep0_stage = CDNS3_SETUP_STAGE;
+	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma,
+			       sizeof(struct usb_ctrlrequest), 0, 0);
+}
+
+static void cdns3_ep0_complete_setup(struct cdns3_device *priv_dev,
+				     u8 send_stall, u8 send_erdy)
+{
+	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
+	struct usb_request *request;
+
+	request = cdns3_next_request(&priv_ep->pending_req_list);
+	if (request)
+		list_del_init(&request->list);
+
+	if (send_stall) {
+		trace_cdns3_halt(priv_ep, send_stall, 0);
+		/* set_stall on ep0 */
+		cdns3_select_ep(priv_dev, 0x00);
+		writel(EP_CMD_SSTALL, &priv_dev->regs->ep_cmd);
+	} else {
+		cdns3_prepare_setup_packet(priv_dev);
+	}
+
+	priv_dev->ep0_stage = CDNS3_SETUP_STAGE;
+	writel((send_erdy ? EP_CMD_ERDY : 0) | EP_CMD_REQ_CMPL,
+	       &priv_dev->regs->ep_cmd);
+
+	cdns3_allow_enable_l1(priv_dev, 1);
+}
+
+/**
+ * cdns3_req_ep0_set_configuration - Handling of SET_CONFIG standard USB request
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, USB_GADGET_DELAYED_STATUS on deferred status stage,
+ * error code on error
+ */
+static int cdns3_req_ep0_set_configuration(struct cdns3_device *priv_dev,
+					   struct usb_ctrlrequest *ctrl_req)
+{
+	enum usb_device_state device_state = priv_dev->gadget.state;
+	struct cdns3_endpoint *priv_ep;
+	u32 config = le16_to_cpu(ctrl_req->wValue);
+	int result = 0;
+	int i;
+
+	switch (device_state) {
+	case USB_STATE_ADDRESS:
+		/* Configure non-control EPs */
+		for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++) {
+			priv_ep = priv_dev->eps[i];
+			if (!priv_ep)
+				continue;
+
+			if (priv_ep->flags & EP_CLAIMED)
+				cdns3_ep_config(priv_ep);
+		}
+
+		result = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
+
+		if (result)
+			return result;
+
+		if (config) {
+			cdns3_set_hw_configuration(priv_dev);
+		} else {
+			cdns3_hw_reset_eps_config(priv_dev);
+			usb_gadget_set_state(&priv_dev->gadget,
+					     USB_STATE_ADDRESS);
+		}
+		break;
+	case USB_STATE_CONFIGURED:
+		result = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
+
+		if (!config && !result) {
+			cdns3_hw_reset_eps_config(priv_dev);
+			usb_gadget_set_state(&priv_dev->gadget,
+					     USB_STATE_ADDRESS);
+		}
+		break;
+	default:
+		result = -EINVAL;
+	}
+
+	return result;
+}
+
+/**
+ * cdns3_req_ep0_set_address - Handling of SET_ADDRESS standard USB request
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_req_ep0_set_address(struct cdns3_device *priv_dev,
+				     struct usb_ctrlrequest *ctrl_req)
+{
+	enum usb_device_state device_state = priv_dev->gadget.state;
+	u32 reg;
+	u32 addr;
+
+	addr = le16_to_cpu(ctrl_req->wValue);
+
+	if (addr > USB_DEVICE_MAX_ADDRESS) {
+		dev_err(priv_dev->dev,
+			"Device address (%d) cannot be greater than %d\n",
+			addr, USB_DEVICE_MAX_ADDRESS);
+		return -EINVAL;
+	}
+
+	if (device_state == USB_STATE_CONFIGURED) {
+		dev_err(priv_dev->dev,
+			"can't set_address from configured state\n");
+		return -EINVAL;
+	}
+
+	reg = readl(&priv_dev->regs->usb_cmd);
+
+	writel(reg | USB_CMD_FADDR(addr) | USB_CMD_SET_ADDR,
+	       &priv_dev->regs->usb_cmd);
+
+	usb_gadget_set_state(&priv_dev->gadget,
+			     (addr ? USB_STATE_ADDRESS : USB_STATE_DEFAULT));
+
+	return 0;
+}
+
+/**
+ * cdns3_req_ep0_get_status - Handling of GET_STATUS standard USB request
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_req_ep0_get_status(struct cdns3_device *priv_dev,
+				    struct usb_ctrlrequest *ctrl)
+{
+	__le16 *response_pkt;
+	u16 usb_status = 0;
+	u32 recip;
+
+	recip = ctrl->bRequestType & USB_RECIP_MASK;
+
+	switch (recip) {
+	case USB_RECIP_DEVICE:
+		/* self powered */
+		if (priv_dev->is_selfpowered)
+			usb_status = BIT(USB_DEVICE_SELF_POWERED);
+
+		if (priv_dev->wake_up_flag)
+			usb_status |= BIT(USB_DEVICE_REMOTE_WAKEUP);
+
+		if (priv_dev->gadget.speed != USB_SPEED_SUPER)
+			break;
+
+		if (priv_dev->u1_allowed)
+			usb_status |= BIT(USB_DEV_STAT_U1_ENABLED);
+
+		if (priv_dev->u2_allowed)
+			usb_status |= BIT(USB_DEV_STAT_U2_ENABLED);
+
+		break;
+	case USB_RECIP_INTERFACE:
+		return cdns3_ep0_delegate_req(priv_dev, ctrl);
+	case USB_RECIP_ENDPOINT:
+		/* check if endpoint is stalled */
+		cdns3_select_ep(priv_dev, ctrl->wIndex);
+		if (EP_STS_STALL(readl(&priv_dev->regs->ep_sts)))
+			usb_status =  BIT(USB_ENDPOINT_HALT);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	response_pkt = (__le16 *)priv_dev->setup_buf;
+	*response_pkt = cpu_to_le16(usb_status);
+
+	/* Flush setup response */
+	flush_dcache_range((unsigned long)priv_dev->setup_buf,
+			   (unsigned long)priv_dev->setup_buf +
+			   ROUND(sizeof(struct usb_ctrlrequest),
+				 CONFIG_SYS_CACHELINE_SIZE));
+
+	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma,
+			       sizeof(*response_pkt), 1, 0);
+	return 0;
+}
+
+static int cdns3_ep0_feature_handle_device(struct cdns3_device *priv_dev,
+					   struct usb_ctrlrequest *ctrl,
+					   int set)
+{
+	enum usb_device_state state;
+	enum usb_device_speed speed;
+	int ret = 0;
+	u16 tmode;
+
+	state = priv_dev->gadget.state;
+	speed = priv_dev->gadget.speed;
+
+	switch (ctrl->wValue) {
+	case USB_DEVICE_REMOTE_WAKEUP:
+		priv_dev->wake_up_flag = !!set;
+		break;
+	case USB_DEVICE_U1_ENABLE:
+		if (state != USB_STATE_CONFIGURED || speed != USB_SPEED_SUPER)
+			return -EINVAL;
+
+		priv_dev->u1_allowed = !!set;
+		break;
+	case USB_DEVICE_U2_ENABLE:
+		if (state != USB_STATE_CONFIGURED || speed != USB_SPEED_SUPER)
+			return -EINVAL;
+
+		priv_dev->u2_allowed = !!set;
+		break;
+	case USB_DEVICE_LTM_ENABLE:
+		ret = -EINVAL;
+		break;
+	case USB_DEVICE_TEST_MODE:
+		if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
+			return -EINVAL;
+
+		tmode = le16_to_cpu(ctrl->wIndex);
+
+		if (!set || (tmode & 0xff) != 0)
+			return -EINVAL;
+
+		switch (tmode >> 8) {
+		case TEST_J:
+		case TEST_K:
+		case TEST_SE0_NAK:
+		case TEST_PACKET:
+			cdns3_ep0_complete_setup(priv_dev, 0, 1);
+			/**
+			 *  Little delay to give the controller some time
+			 * for sending status stage.
+			 * This time should be less then 3ms.
+			 */
+			usleep_range(1000, 2000);
+			cdns3_set_register_bit(&priv_dev->regs->usb_cmd,
+					       USB_CMD_STMODE |
+					       USB_STS_TMODE_SEL(tmode - 1));
+			break;
+		default:
+			ret = -EINVAL;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int cdns3_ep0_feature_handle_intf(struct cdns3_device *priv_dev,
+					 struct usb_ctrlrequest *ctrl,
+					 int set)
+{
+	u32 wValue;
+	int ret = 0;
+
+	wValue = le16_to_cpu(ctrl->wValue);
+
+	switch (wValue) {
+	case USB_INTRF_FUNC_SUSPEND:
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int cdns3_ep0_feature_handle_endpoint(struct cdns3_device *priv_dev,
+					     struct usb_ctrlrequest *ctrl,
+					     int set)
+{
+	struct cdns3_endpoint *priv_ep;
+	int ret = 0;
+	u8 index;
+
+	if (le16_to_cpu(ctrl->wValue) != USB_ENDPOINT_HALT)
+		return -EINVAL;
+
+	if (!(ctrl->wIndex & ~USB_DIR_IN))
+		return 0;
+
+	index = cdns3_ep_addr_to_index(ctrl->wIndex);
+	priv_ep = priv_dev->eps[index];
+
+	cdns3_select_ep(priv_dev, ctrl->wIndex);
+
+	if (set)
+		__cdns3_gadget_ep_set_halt(priv_ep);
+	else if (!(priv_ep->flags & EP_WEDGE))
+		ret = __cdns3_gadget_ep_clear_halt(priv_ep);
+
+	cdns3_select_ep(priv_dev, 0x00);
+
+	return ret;
+}
+
+/**
+ * cdns3_req_ep0_handle_feature -
+ * Handling of GET/SET_FEATURE standard USB request
+ *
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ * @set: must be set to 1 for SET_FEATURE request
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_req_ep0_handle_feature(struct cdns3_device *priv_dev,
+					struct usb_ctrlrequest *ctrl,
+					int set)
+{
+	int ret = 0;
+	u32 recip;
+
+	recip = ctrl->bRequestType & USB_RECIP_MASK;
+
+	switch (recip) {
+	case USB_RECIP_DEVICE:
+		ret = cdns3_ep0_feature_handle_device(priv_dev, ctrl, set);
+		break;
+	case USB_RECIP_INTERFACE:
+		ret = cdns3_ep0_feature_handle_intf(priv_dev, ctrl, set);
+		break;
+	case USB_RECIP_ENDPOINT:
+		ret = cdns3_ep0_feature_handle_endpoint(priv_dev, ctrl, set);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+/**
+ * cdns3_req_ep0_set_sel - Handling of SET_SEL standard USB request
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_req_ep0_set_sel(struct cdns3_device *priv_dev,
+				 struct usb_ctrlrequest *ctrl_req)
+{
+	if (priv_dev->gadget.state < USB_STATE_ADDRESS)
+		return -EINVAL;
+
+	if (ctrl_req->wLength != 6) {
+		dev_err(priv_dev->dev, "Set SEL should be 6 bytes, got %d\n",
+			ctrl_req->wLength);
+		return -EINVAL;
+	}
+
+	cdns3_ep0_run_transfer(priv_dev, priv_dev->setup_dma, 6, 1, 0);
+	return 0;
+}
+
+/**
+ * cdns3_req_ep0_set_isoch_delay -
+ * Handling of GET_ISOCH_DELAY standard USB request
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_req_ep0_set_isoch_delay(struct cdns3_device *priv_dev,
+					 struct usb_ctrlrequest *ctrl_req)
+{
+	if (ctrl_req->wIndex || ctrl_req->wLength)
+		return -EINVAL;
+
+	priv_dev->isoch_delay = ctrl_req->wValue;
+
+	return 0;
+}
+
+/**
+ * cdns3_ep0_standard_request - Handling standard USB requests
+ * @priv_dev: extended gadget object
+ * @ctrl_req: pointer to received setup packet
+ *
+ * Returns 0 if success, error code on error
+ */
+static int cdns3_ep0_standard_request(struct cdns3_device *priv_dev,
+				      struct usb_ctrlrequest *ctrl_req)
+{
+	int ret;
+
+	switch (ctrl_req->bRequest) {
+	case USB_REQ_SET_ADDRESS:
+		ret = cdns3_req_ep0_set_address(priv_dev, ctrl_req);
+		break;
+	case USB_REQ_SET_CONFIGURATION:
+		ret = cdns3_req_ep0_set_configuration(priv_dev, ctrl_req);
+		break;
+	case USB_REQ_GET_STATUS:
+		ret = cdns3_req_ep0_get_status(priv_dev, ctrl_req);
+		break;
+	case USB_REQ_CLEAR_FEATURE:
+		ret = cdns3_req_ep0_handle_feature(priv_dev, ctrl_req, 0);
+		break;
+	case USB_REQ_SET_FEATURE:
+		ret = cdns3_req_ep0_handle_feature(priv_dev, ctrl_req, 1);
+		break;
+	case USB_REQ_SET_SEL:
+		ret = cdns3_req_ep0_set_sel(priv_dev, ctrl_req);
+		break;
+	case USB_REQ_SET_ISOCH_DELAY:
+		ret = cdns3_req_ep0_set_isoch_delay(priv_dev, ctrl_req);
+		break;
+	default:
+		ret = cdns3_ep0_delegate_req(priv_dev, ctrl_req);
+		break;
+	}
+
+	return ret;
+}
+
+static void __pending_setup_status_handler(struct cdns3_device *priv_dev)
+{
+	struct usb_request *request = priv_dev->pending_status_request;
+
+	if (priv_dev->status_completion_no_call && request &&
+	    request->complete) {
+		request->complete(&priv_dev->eps[0]->endpoint, request);
+		priv_dev->status_completion_no_call = 0;
+	}
+}
+
+void cdns3_pending_setup_status_handler(struct work_struct *work)
+{
+	struct cdns3_device *priv_dev = container_of(work, struct cdns3_device,
+			pending_status_wq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	__pending_setup_status_handler(priv_dev);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+}
+
+/**
+ * cdns3_ep0_setup_phase - Handling setup USB requests
+ * @priv_dev: extended gadget object
+ */
+static void cdns3_ep0_setup_phase(struct cdns3_device *priv_dev)
+{
+	struct usb_ctrlrequest *ctrl = priv_dev->setup_buf;
+	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
+	int result;
+
+	priv_dev->ep0_data_dir = ctrl->bRequestType & USB_DIR_IN;
+
+	trace_cdns3_ctrl_req(ctrl);
+
+	if (!list_empty(&priv_ep->pending_req_list)) {
+		struct usb_request *request;
+
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+		priv_ep->dir = priv_dev->ep0_data_dir;
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
+				      -ECONNRESET);
+	}
+
+	if (le16_to_cpu(ctrl->wLength))
+		priv_dev->ep0_stage = CDNS3_DATA_STAGE;
+	else
+		priv_dev->ep0_stage = CDNS3_STATUS_STAGE;
+
+	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
+		result = cdns3_ep0_standard_request(priv_dev, ctrl);
+	else
+		result = cdns3_ep0_delegate_req(priv_dev, ctrl);
+
+	if (result == USB_GADGET_DELAYED_STATUS)
+		return;
+
+	if (result < 0)
+		cdns3_ep0_complete_setup(priv_dev, 1, 1);
+	else if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE)
+		cdns3_ep0_complete_setup(priv_dev, 0, 1);
+}
+
+static void cdns3_transfer_completed(struct cdns3_device *priv_dev)
+{
+	struct cdns3_endpoint *priv_ep = priv_dev->eps[0];
+
+	if (!list_empty(&priv_ep->pending_req_list)) {
+		struct usb_request *request;
+
+		trace_cdns3_complete_trb(priv_ep, priv_ep->trb_pool);
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+
+		/* Invalidate TRB before accessing it */
+		invalidate_dcache_range((unsigned long)priv_ep->trb_pool,
+					(unsigned long)priv_ep->trb_pool +
+					ROUND(sizeof(struct cdns3_trb),
+					      CONFIG_SYS_CACHELINE_SIZE));
+
+		request->actual =
+			TRB_LEN(le32_to_cpu(priv_ep->trb_pool->length));
+
+		priv_ep->dir = priv_dev->ep0_data_dir;
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request), 0);
+	}
+
+	cdns3_ep0_complete_setup(priv_dev, 0, 0);
+}
+
+/**
+ * cdns3_check_new_setup - Check if controller receive new SETUP packet.
+ * @priv_dev: extended gadget object
+ *
+ * The SETUP packet can be kept in on-chip memory or in system memory.
+ */
+static bool cdns3_check_new_setup(struct cdns3_device *priv_dev)
+{
+	u32 ep_sts_reg;
+
+	cdns3_select_ep(priv_dev, 0 | USB_DIR_OUT);
+	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+
+	return !!(ep_sts_reg & (EP_STS_SETUP | EP_STS_STPWAIT));
+}
+
+/**
+ * cdns3_check_ep0_interrupt_proceed - Processes interrupt related to endpoint 0
+ * @priv_dev: extended gadget object
+ * @dir: USB_DIR_IN for IN direction, USB_DIR_OUT for OUT direction
+ */
+void cdns3_check_ep0_interrupt_proceed(struct cdns3_device *priv_dev, int dir)
+{
+	u32 ep_sts_reg;
+
+	cdns3_select_ep(priv_dev, dir);
+
+	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+	writel(ep_sts_reg, &priv_dev->regs->ep_sts);
+
+	trace_cdns3_ep0_irq(priv_dev, ep_sts_reg);
+
+	__pending_setup_status_handler(priv_dev);
+
+	if (ep_sts_reg & EP_STS_SETUP)
+		priv_dev->wait_for_setup = 1;
+
+	if (priv_dev->wait_for_setup && ep_sts_reg & EP_STS_IOC) {
+		priv_dev->wait_for_setup = 0;
+		cdns3_allow_enable_l1(priv_dev, 0);
+		cdns3_ep0_setup_phase(priv_dev);
+	} else if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP)) {
+		priv_dev->ep0_data_dir = dir;
+		cdns3_transfer_completed(priv_dev);
+	}
+
+	if (ep_sts_reg & EP_STS_DESCMIS) {
+		if (dir == 0 && !priv_dev->setup_pending)
+			cdns3_prepare_setup_packet(priv_dev);
+	}
+}
+
+/**
+ * cdns3_gadget_ep0_enable
+ * Function shouldn't be called by gadget driver,
+ * endpoint 0 is allways active
+ */
+static int cdns3_gadget_ep0_enable(struct usb_ep *ep,
+				   const struct usb_endpoint_descriptor *desc)
+{
+	return -EINVAL;
+}
+
+/**
+ * cdns3_gadget_ep0_disable
+ * Function shouldn't be called by gadget driver,
+ * endpoint 0 is allways active
+ */
+static int cdns3_gadget_ep0_disable(struct usb_ep *ep)
+{
+	return -EINVAL;
+}
+
+/**
+ * cdns3_gadget_ep0_set_halt
+ * @ep: pointer to endpoint zero object
+ * @value: 1 for set stall, 0 for clear stall
+ *
+ * Returns 0
+ */
+static int cdns3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
+{
+	/* TODO */
+	return 0;
+}
+
+/**
+ * cdns3_gadget_ep0_queue Transfer data on endpoint zero
+ * @ep: pointer to endpoint zero object
+ * @request: pointer to request object
+ * @gfp_flags: gfp flags
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
+				  struct usb_request *request,
+				  gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	unsigned long flags;
+	int erdy_sent = 0;
+	int ret = 0;
+	u8 zlp = 0;
+
+	trace_cdns3_ep0_queue(priv_dev, request);
+
+	/* cancel the request if controller receive new SETUP packet. */
+	if (cdns3_check_new_setup(priv_dev))
+		return -ECONNRESET;
+
+	/* send STATUS stage. Should be called only for SET_CONFIGURATION */
+	if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE) {
+		spin_lock_irqsave(&priv_dev->lock, flags);
+		cdns3_select_ep(priv_dev, 0x00);
+
+		erdy_sent = !priv_dev->hw_configured_flag;
+		cdns3_set_hw_configuration(priv_dev);
+
+		if (!erdy_sent)
+			cdns3_ep0_complete_setup(priv_dev, 0, 1);
+
+		cdns3_allow_enable_l1(priv_dev, 1);
+
+		request->actual = 0;
+		priv_dev->status_completion_no_call = true;
+		priv_dev->pending_status_request = request;
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+		/*
+		 * Since there is no completion interrupt for status stage,
+		 * it needs to call ->completion in software after
+		 * ep0_queue is back.
+		 */
+#ifndef __UBOOT__
+		queue_work(system_freezable_wq, &priv_dev->pending_status_wq);
+#else
+		__pending_setup_status_handler(priv_dev);
+#endif
+		return 0;
+	}
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	if (!list_empty(&priv_ep->pending_req_list)) {
+		dev_err(priv_dev->dev,
+			"can't handle multiple requests for ep0\n");
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+		return -EBUSY;
+	}
+
+	ret = usb_gadget_map_request(&priv_dev->gadget, request,
+				     priv_dev->ep0_data_dir);
+	if (ret) {
+		spin_unlock_irqrestore(&priv_dev->lock, flags);
+		dev_err(priv_dev->dev, "failed to map request\n");
+		return -EINVAL;
+	}
+
+	request->status = -EINPROGRESS;
+	list_add_tail(&request->list, &priv_ep->pending_req_list);
+
+	if (request->zero && request->length &&
+	    (request->length % ep->maxpacket == 0))
+		zlp = 1;
+
+	cdns3_ep0_run_transfer(priv_dev, request->dma, request->length, 1, zlp);
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_set_wedge Set wedge on selected endpoint
+ * @ep: endpoint object
+ *
+ * Returns 0
+ */
+int cdns3_gadget_ep_set_wedge(struct usb_ep *ep)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+
+	dev_dbg(priv_dev->dev, "Wedge for %s\n", ep->name);
+	cdns3_gadget_ep_set_halt(ep, 1);
+	priv_ep->flags |= EP_WEDGE;
+
+	return 0;
+}
+
+const struct usb_ep_ops cdns3_gadget_ep0_ops = {
+	.enable = cdns3_gadget_ep0_enable,
+	.disable = cdns3_gadget_ep0_disable,
+	.alloc_request = cdns3_gadget_ep_alloc_request,
+	.free_request = cdns3_gadget_ep_free_request,
+	.queue = cdns3_gadget_ep0_queue,
+	.dequeue = cdns3_gadget_ep_dequeue,
+	.set_halt = cdns3_gadget_ep0_set_halt,
+	.set_wedge = cdns3_gadget_ep_set_wedge,
+};
+
+/**
+ * cdns3_ep0_config - Configures default endpoint
+ * @priv_dev: extended gadget object
+ *
+ * Functions sets parameters: maximal packet size and enables interrupts
+ */
+void cdns3_ep0_config(struct cdns3_device *priv_dev)
+{
+	struct cdns3_usb_regs __iomem *regs;
+	struct cdns3_endpoint *priv_ep;
+	u32 max_packet_size = 64;
+
+	regs = priv_dev->regs;
+
+	if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+		max_packet_size = 512;
+
+	priv_ep = priv_dev->eps[0];
+
+	if (!list_empty(&priv_ep->pending_req_list)) {
+		struct usb_request *request;
+
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+		list_del_init(&request->list);
+	}
+
+	priv_dev->u1_allowed = 0;
+	priv_dev->u2_allowed = 0;
+
+	priv_dev->gadget.ep0->maxpacket = max_packet_size;
+	cdns3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(max_packet_size);
+
+	/* init ep out */
+	cdns3_select_ep(priv_dev, USB_DIR_OUT);
+
+	if (priv_dev->dev_ver >= DEV_VER_V3) {
+		cdns3_set_register_bit(&priv_dev->regs->dtrans,
+				       BIT(0) | BIT(16));
+		cdns3_set_register_bit(&priv_dev->regs->tdl_from_trb,
+				       BIT(0) | BIT(16));
+	}
+
+	writel(EP_CFG_ENABLE | EP_CFG_MAXPKTSIZE(max_packet_size),
+	       &regs->ep_cfg);
+
+	writel(EP_STS_EN_SETUPEN | EP_STS_EN_DESCMISEN | EP_STS_EN_TRBERREN,
+	       &regs->ep_sts_en);
+
+	/* init ep in */
+	cdns3_select_ep(priv_dev, USB_DIR_IN);
+
+	writel(EP_CFG_ENABLE | EP_CFG_MAXPKTSIZE(max_packet_size),
+	       &regs->ep_cfg);
+
+	writel(EP_STS_EN_SETUPEN | EP_STS_EN_TRBERREN, &regs->ep_sts_en);
+
+	cdns3_set_register_bit(&regs->usb_conf, USB_CONF_U1DS | USB_CONF_U2DS);
+}
+
+/**
+ * cdns3_init_ep0 Initializes software endpoint 0 of gadget
+ * @priv_dev: extended gadget object
+ * @ep_priv: extended endpoint object
+ *
+ * Returns 0 on success else error code.
+ */
+int cdns3_init_ep0(struct cdns3_device *priv_dev,
+		   struct cdns3_endpoint *priv_ep)
+{
+	sprintf(priv_ep->name, "ep0");
+
+	/* fill linux fields */
+	priv_ep->endpoint.ops = &cdns3_gadget_ep0_ops;
+	priv_ep->endpoint.maxburst = 1;
+	usb_ep_set_maxpacket_limit(&priv_ep->endpoint,
+				   CDNS3_EP0_MAX_PACKET_LIMIT);
+#ifndef __UBOOT__
+	priv_ep->endpoint.address = 0;
+#endif
+	priv_ep->endpoint.caps.type_control = 1;
+	priv_ep->endpoint.caps.dir_in = 1;
+	priv_ep->endpoint.caps.dir_out = 1;
+	priv_ep->endpoint.name = priv_ep->name;
+	priv_ep->endpoint.desc = &cdns3_gadget_ep0_desc;
+	priv_dev->gadget.ep0 = &priv_ep->endpoint;
+	priv_ep->type = USB_ENDPOINT_XFER_CONTROL;
+
+	return cdns3_allocate_trb_pool(priv_ep);
+}
diff --git a/drivers/usb/cdns3/gadget-export.h b/drivers/usb/cdns3/gadget-export.h
new file mode 100644
index 0000000..577469e
--- /dev/null
+++ b/drivers/usb/cdns3/gadget-export.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Cadence USBSS DRD Driver - Gadget Export APIs.
+ *
+ * Copyright (C) 2017 NXP
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Peter Chen <peter.chen@nxp.com>
+ */
+#ifndef __LINUX_CDNS3_GADGET_EXPORT
+#define __LINUX_CDNS3_GADGET_EXPORT
+
+#ifdef CONFIG_USB_CDNS3_GADGET
+
+int cdns3_gadget_init(struct cdns3 *cdns);
+void cdns3_gadget_exit(struct cdns3 *cdns);
+#else
+
+static inline int cdns3_gadget_init(struct cdns3 *cdns)
+{
+	return -ENXIO;
+}
+
+static inline void cdns3_gadget_exit(struct cdns3 *cdns) { }
+
+#endif
+
+#endif /* __LINUX_CDNS3_GADGET_EXPORT */
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
new file mode 100644
index 0000000..a4debb0
--- /dev/null
+++ b/drivers/usb/cdns3/gadget.c
@@ -0,0 +1,2738 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - gadget side.
+ *
+ * Copyright (C) 2018-2019 Cadence Design Systems.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Pawel Jez <pjez@cadence.com>,
+ *          Pawel Laszczak <pawell@cadence.com>
+ *          Peter Chen <peter.chen@nxp.com>
+ */
+
+/*
+ * Work around 1:
+ * At some situations, the controller may get stale data address in TRB
+ * at below sequences:
+ * 1. Controller read TRB includes data address
+ * 2. Software updates TRBs includes data address and Cycle bit
+ * 3. Controller read TRB which includes Cycle bit
+ * 4. DMA run with stale data address
+ *
+ * To fix this problem, driver needs to make the first TRB in TD as invalid.
+ * After preparing all TRBs driver needs to check the position of DMA and
+ * if the DMA point to the first just added TRB and doorbell is 1,
+ * then driver must defer making this TRB as valid. This TRB will be make
+ * as valid during adding next TRB only if DMA is stopped or at TRBERR
+ * interrupt.
+ *
+ * Issue has been fixed in DEV_VER_V3 version of controller.
+ *
+ * Work around 2:
+ * Controller for OUT endpoints has shared on-chip buffers for all incoming
+ * packets, including ep0out. It's FIFO buffer, so packets must be handle by DMA
+ * in correct order. If the first packet in the buffer will not be handled,
+ * then the following packets directed for other endpoints and  functions
+ * will be blocked.
+ * Additionally the packets directed to one endpoint can block entire on-chip
+ * buffers. In this case transfer to other endpoints also will blocked.
+ *
+ * To resolve this issue after raising the descriptor missing interrupt
+ * driver prepares internal usb_request object and use it to arm DMA transfer.
+ *
+ * The problematic situation was observed in case when endpoint has been enabled
+ * but no usb_request were queued. Driver try detects such endpoints and will
+ * use this workaround only for these endpoint.
+ *
+ * Driver use limited number of buffer. This number can be set by macro
+ * CDNS3_WA2_NUM_BUFFERS.
+ *
+ * Such blocking situation was observed on ACM gadget. For this function
+ * host send OUT data packet but ACM function is not prepared for this packet.
+ * It's cause that buffer placed in on chip memory block transfer to other
+ * endpoints.
+ *
+ * Issue has been fixed in DEV_VER_V2 version of controller.
+ *
+ */
+
+#include <dm.h>
+#include <linux/usb/gadget.h>
+#include <linux/compat.h>
+#include <linux/iopoll.h>
+#include <asm/dma-mapping.h>
+#include <linux/bitmap.h>
+#include <linux/bug.h>
+
+#include "core.h"
+#include "gadget-export.h"
+#include "gadget.h"
+#include "trace.h"
+#include "drd.h"
+
+#define readl_poll_timeout_atomic readl_poll_timeout
+#define usleep_range(a, b) udelay((b))
+
+static int __cdns3_gadget_ep_queue(struct usb_ep *ep,
+				   struct usb_request *request,
+				   gfp_t gfp_flags);
+
+/**
+ * cdns3_set_register_bit - set bit in given register.
+ * @ptr: address of device controller register to be read and changed
+ * @mask: bits requested to set
+ */
+void cdns3_set_register_bit(void __iomem *ptr, u32 mask)
+{
+	mask = readl(ptr) | mask;
+	writel(mask, ptr);
+}
+
+/**
+ * cdns3_ep_addr_to_index - Macro converts endpoint address to
+ * index of endpoint object in cdns3_device.eps[] container
+ * @ep_addr: endpoint address for which endpoint object is required
+ *
+ */
+u8 cdns3_ep_addr_to_index(u8 ep_addr)
+{
+	return (((ep_addr & 0x7F)) + ((ep_addr & USB_DIR_IN) ? 16 : 0));
+}
+
+static int cdns3_get_dma_pos(struct cdns3_device *priv_dev,
+			     struct cdns3_endpoint *priv_ep)
+{
+	int dma_index;
+
+	dma_index = readl(&priv_dev->regs->ep_traddr) - priv_ep->trb_pool_dma;
+
+	return dma_index / TRB_SIZE;
+}
+
+/**
+ * cdns3_next_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct usb_request *cdns3_next_request(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct usb_request, list);
+}
+
+/**
+ * cdns3_next_align_buf - returns next buffer from list
+ * @list: list containing buffers
+ *
+ * Returns buffer or NULL if no buffers in list
+ */
+struct cdns3_aligned_buf *cdns3_next_align_buf(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct cdns3_aligned_buf, list);
+}
+
+/**
+ * cdns3_next_priv_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct cdns3_request *cdns3_next_priv_request(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct cdns3_request, list);
+}
+
+/**
+ * select_ep - selects endpoint
+ * @priv_dev:  extended gadget object
+ * @ep: endpoint address
+ */
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep)
+{
+	if (priv_dev->selected_ep == ep)
+		return;
+
+	priv_dev->selected_ep = ep;
+	writel(ep, &priv_dev->regs->ep_sel);
+}
+
+dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
+				 struct cdns3_trb *trb)
+{
+	u32 offset = (char *)trb - (char *)priv_ep->trb_pool;
+
+	return priv_ep->trb_pool_dma + offset;
+}
+
+int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
+{
+	switch (priv_ep->type) {
+	case USB_ENDPOINT_XFER_ISOC:
+		return TRB_ISO_RING_SIZE;
+	case USB_ENDPOINT_XFER_CONTROL:
+		return TRB_CTRL_RING_SIZE;
+	default:
+		return TRB_RING_SIZE;
+	}
+}
+
+/**
+ * cdns3_allocate_trb_pool - Allocates TRB's pool for selected endpoint
+ * @priv_ep:  endpoint object
+ *
+ * Function will return 0 on success or -ENOMEM on allocation error
+ */
+int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+	int ring_size = cdns3_ring_size(priv_ep);
+	struct cdns3_trb *link_trb;
+
+	if (!priv_ep->trb_pool) {
+		priv_ep->trb_pool =
+		dma_alloc_coherent(ring_size,
+				   (unsigned long *)&priv_ep->trb_pool_dma);
+		if (!priv_ep->trb_pool)
+			return -ENOMEM;
+	} else {
+		memset(priv_ep->trb_pool, 0, ring_size);
+	}
+
+	if (!priv_ep->num)
+		return 0;
+
+	priv_ep->num_trbs = ring_size / TRB_SIZE;
+	/* Initialize the last TRB as Link TRB. */
+	link_trb = (priv_ep->trb_pool + (priv_ep->num_trbs - 1));
+	link_trb->buffer = TRB_BUFFER(priv_ep->trb_pool_dma);
+	link_trb->control = TRB_CYCLE | TRB_TYPE(TRB_LINK) | TRB_TOGGLE;
+
+	return 0;
+}
+
+static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+	if (priv_ep->trb_pool) {
+		dma_free_coherent(priv_ep->trb_pool);
+		priv_ep->trb_pool = NULL;
+	}
+}
+
+/**
+ * cdns3_ep_stall_flush - Stalls and flushes selected endpoint
+ * @priv_ep: endpoint object
+ *
+ * Endpoint must be selected before call to this function
+ */
+static void cdns3_ep_stall_flush(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	int val;
+
+	trace_cdns3_halt(priv_ep, 1, 1);
+
+	writel(EP_CMD_DFLUSH | EP_CMD_ERDY | EP_CMD_SSTALL,
+	       &priv_dev->regs->ep_cmd);
+
+	/* wait for DFLUSH cleared */
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+				  !(val & EP_CMD_DFLUSH), 1000);
+	priv_ep->flags |= EP_STALLED;
+	priv_ep->flags &= ~EP_STALL_PENDING;
+}
+
+/**
+ * cdns3_hw_reset_eps_config - reset endpoints configuration kept by controller.
+ * @priv_dev: extended gadget object
+ */
+void cdns3_hw_reset_eps_config(struct cdns3_device *priv_dev)
+{
+	writel(USB_CONF_CFGRST, &priv_dev->regs->usb_conf);
+
+	cdns3_allow_enable_l1(priv_dev, 0);
+	priv_dev->hw_configured_flag = 0;
+	priv_dev->onchip_used_size = 0;
+	priv_dev->out_mem_is_allocated = 0;
+	priv_dev->wait_for_setup = 0;
+}
+
+/**
+ * cdns3_ep_inc_trb - increment a trb index.
+ * @index: Pointer to the TRB index to increment.
+ * @cs: Cycle state
+ * @trb_in_seg: number of TRBs in segment
+ *
+ * The index should never point to the link TRB. After incrementing,
+ * if it is point to the link TRB, wrap around to the beginning and revert
+ * cycle state bit The
+ * link TRB is always at the last TRB entry.
+ */
+static void cdns3_ep_inc_trb(int *index, u8 *cs, int trb_in_seg)
+{
+	(*index)++;
+	if (*index == (trb_in_seg - 1)) {
+		*index = 0;
+		*cs ^=  1;
+	}
+}
+
+/**
+ * cdns3_ep_inc_enq - increment endpoint's enqueue pointer
+ * @priv_ep: The endpoint whose enqueue pointer we're incrementing
+ */
+static void cdns3_ep_inc_enq(struct cdns3_endpoint *priv_ep)
+{
+	priv_ep->free_trbs--;
+	cdns3_ep_inc_trb(&priv_ep->enqueue, &priv_ep->pcs, priv_ep->num_trbs);
+}
+
+/**
+ * cdns3_ep_inc_deq - increment endpoint's dequeue pointer
+ * @priv_ep: The endpoint whose dequeue pointer we're incrementing
+ */
+static void cdns3_ep_inc_deq(struct cdns3_endpoint *priv_ep)
+{
+	priv_ep->free_trbs++;
+	cdns3_ep_inc_trb(&priv_ep->dequeue, &priv_ep->ccs, priv_ep->num_trbs);
+}
+
+void cdns3_move_deq_to_next_trb(struct cdns3_request *priv_req)
+{
+	struct cdns3_endpoint *priv_ep = priv_req->priv_ep;
+	int current_trb = priv_req->start_trb;
+
+	while (current_trb != priv_req->end_trb) {
+		cdns3_ep_inc_deq(priv_ep);
+		current_trb = priv_ep->dequeue;
+	}
+
+	cdns3_ep_inc_deq(priv_ep);
+}
+
+/**
+ * cdns3_allow_enable_l1 - enable/disable permits to transition to L1.
+ * @priv_dev: Extended gadget object
+ * @enable: Enable/disable permit to transition to L1.
+ *
+ * If bit USB_CONF_L1EN is set and device receive Extended Token packet,
+ * then controller answer with ACK handshake.
+ * If bit USB_CONF_L1DS is set and device receive Extended Token packet,
+ * then controller answer with NYET handshake.
+ */
+void cdns3_allow_enable_l1(struct cdns3_device *priv_dev, int enable)
+{
+	if (enable)
+		writel(USB_CONF_L1EN, &priv_dev->regs->usb_conf);
+	else
+		writel(USB_CONF_L1DS, &priv_dev->regs->usb_conf);
+}
+
+enum usb_device_speed cdns3_get_speed(struct cdns3_device *priv_dev)
+{
+	u32 reg;
+
+	reg = readl(&priv_dev->regs->usb_sts);
+
+	if (DEV_SUPERSPEED(reg))
+		return USB_SPEED_SUPER;
+	else if (DEV_HIGHSPEED(reg))
+		return USB_SPEED_HIGH;
+	else if (DEV_FULLSPEED(reg))
+		return USB_SPEED_FULL;
+	else if (DEV_LOWSPEED(reg))
+		return USB_SPEED_LOW;
+	return USB_SPEED_UNKNOWN;
+}
+
+/**
+ * cdns3_start_all_request - add to ring all request not started
+ * @priv_dev: Extended gadget object
+ * @priv_ep: The endpoint for whom request will be started.
+ *
+ * Returns return ENOMEM if transfer ring i not enough TRBs to start
+ *         all requests.
+ */
+static int cdns3_start_all_request(struct cdns3_device *priv_dev,
+				   struct cdns3_endpoint *priv_ep)
+{
+	struct usb_request *request;
+	int ret = 0;
+
+	while (!list_empty(&priv_ep->deferred_req_list)) {
+		request = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		ret = cdns3_ep_run_transfer(priv_ep, request);
+		if (ret)
+			return ret;
+
+		list_del(&request->list);
+		list_add_tail(&request->list,
+			      &priv_ep->pending_req_list);
+	}
+
+	priv_ep->flags &= ~EP_RING_FULL;
+	return ret;
+}
+
+/*
+ * WA2: Set flag for all not ISOC OUT endpoints. If this flag is set
+ * driver try to detect whether endpoint need additional internal
+ * buffer for unblocking on-chip FIFO buffer. This flag will be cleared
+ * if before first DESCMISS interrupt the DMA will be armed.
+ */
+#define cdns3_wa2_enable_detection(priv_dev, ep_priv, reg) do { \
+	if (!priv_ep->dir && priv_ep->type != USB_ENDPOINT_XFER_ISOC) { \
+		priv_ep->flags |= EP_QUIRK_EXTRA_BUF_DET; \
+		(reg) |= EP_STS_EN_DESCMISEN; \
+	} } while (0)
+
+/**
+ * cdns3_wa2_descmiss_copy_data copy data from internal requests to
+ * request queued by class driver.
+ * @priv_ep: extended endpoint object
+ * @request: request object
+ */
+static void cdns3_wa2_descmiss_copy_data(struct cdns3_endpoint *priv_ep,
+					 struct usb_request *request)
+{
+	struct usb_request *descmiss_req;
+	struct cdns3_request *descmiss_priv_req;
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		int chunk_end;
+		int length;
+
+		descmiss_priv_req =
+			cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+		descmiss_req = &descmiss_priv_req->request;
+
+		/* driver can't touch pending request */
+		if (descmiss_priv_req->flags & REQUEST_PENDING)
+			break;
+
+		chunk_end = descmiss_priv_req->flags & REQUEST_INTERNAL_CH;
+		length = request->actual + descmiss_req->actual;
+
+		request->status = descmiss_req->status;
+
+		if (length <= request->length) {
+			memcpy(&((u8 *)request->buf)[request->actual],
+			       descmiss_req->buf,
+			       descmiss_req->actual);
+			request->actual = length;
+		} else {
+			/* It should never occur */
+			request->status = -ENOMEM;
+		}
+
+		list_del_init(&descmiss_priv_req->list);
+
+		kfree(descmiss_req->buf);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, descmiss_req);
+		--priv_ep->wa2_counter;
+
+		if (!chunk_end)
+			break;
+	}
+}
+
+struct usb_request *cdns3_wa2_gadget_giveback(struct cdns3_device *priv_dev,
+					      struct cdns3_endpoint *priv_ep,
+					      struct cdns3_request *priv_req)
+{
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN &&
+	    priv_req->flags & REQUEST_INTERNAL) {
+		struct usb_request *req;
+
+		req = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		priv_ep->descmis_req = NULL;
+
+		if (!req)
+			return NULL;
+
+		cdns3_wa2_descmiss_copy_data(priv_ep, req);
+		if (!(priv_ep->flags & EP_QUIRK_END_TRANSFER) &&
+		    req->length != req->actual) {
+			/* wait for next part of transfer */
+			return NULL;
+		}
+
+		if (req->status == -EINPROGRESS)
+			req->status = 0;
+
+		list_del_init(&req->list);
+		cdns3_start_all_request(priv_dev, priv_ep);
+		return req;
+	}
+
+	return &priv_req->request;
+}
+
+int cdns3_wa2_gadget_ep_queue(struct cdns3_device *priv_dev,
+			      struct cdns3_endpoint *priv_ep,
+			      struct cdns3_request *priv_req)
+{
+	int deferred = 0;
+
+	/*
+	 * If transfer was queued before DESCMISS appear than we
+	 * can disable handling of DESCMISS interrupt. Driver assumes that it
+	 * can disable special treatment for this endpoint.
+	 */
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+		u32 reg;
+
+		cdns3_select_ep(priv_dev, priv_ep->num | priv_ep->dir);
+		priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+		reg = readl(&priv_dev->regs->ep_sts_en);
+		reg &= ~EP_STS_EN_DESCMISEN;
+		trace_cdns3_wa2(priv_ep, "workaround disabled\n");
+		writel(reg, &priv_dev->regs->ep_sts_en);
+	}
+
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+		u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+		u8 descmiss_empty = list_empty(&priv_ep->wa2_descmiss_req_list);
+
+		/*
+		 *  DESCMISS transfer has been finished, so data will be
+		 *  directly copied from internal allocated usb_request
+		 *  objects.
+		 */
+		if (pending_empty && !descmiss_empty &&
+		    !(priv_req->flags & REQUEST_INTERNAL)) {
+			cdns3_wa2_descmiss_copy_data(priv_ep,
+						     &priv_req->request);
+
+			trace_cdns3_wa2(priv_ep, "get internal stored data");
+
+			list_add_tail(&priv_req->request.list,
+				      &priv_ep->pending_req_list);
+			cdns3_gadget_giveback(priv_ep, priv_req,
+					      priv_req->request.status);
+
+			/*
+			 * Intentionally driver returns positive value as
+			 * correct value. It informs that transfer has
+			 * been finished.
+			 */
+			return EINPROGRESS;
+		}
+
+		/*
+		 * Driver will wait for completion DESCMISS transfer,
+		 * before starts new, not DESCMISS transfer.
+		 */
+		if (!pending_empty && !descmiss_empty) {
+			trace_cdns3_wa2(priv_ep, "wait for pending transfer\n");
+			deferred = 1;
+		}
+
+		if (priv_req->flags & REQUEST_INTERNAL)
+			list_add_tail(&priv_req->list,
+				      &priv_ep->wa2_descmiss_req_list);
+	}
+
+	return deferred;
+}
+
+static void cdns3_wa2_remove_old_request(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		u8 chain;
+
+		priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+		chain = !!(priv_req->flags & REQUEST_INTERNAL_CH);
+
+		trace_cdns3_wa2(priv_ep, "removes eldest request");
+
+		kfree(priv_req->request.buf);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+					     &priv_req->request);
+		list_del_init(&priv_req->list);
+		--priv_ep->wa2_counter;
+
+		if (!chain)
+			break;
+	}
+}
+
+/**
+ * cdns3_wa2_descmissing_packet - handles descriptor missing event.
+ * @priv_dev: extended gadget object
+ *
+ * This function is used only for WA2. For more information see Work around 2
+ * description.
+ */
+static void cdns3_wa2_descmissing_packet(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+	struct usb_request *request;
+
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+		priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+		priv_ep->flags |= EP_QUIRK_EXTRA_BUF_EN;
+	}
+
+	trace_cdns3_wa2(priv_ep, "Description Missing detected\n");
+
+	if (priv_ep->wa2_counter >= CDNS3_WA2_NUM_BUFFERS)
+		cdns3_wa2_remove_old_request(priv_ep);
+
+	request = cdns3_gadget_ep_alloc_request(&priv_ep->endpoint,
+						GFP_ATOMIC);
+	if (!request)
+		goto err;
+
+	priv_req = to_cdns3_request(request);
+	priv_req->flags |= REQUEST_INTERNAL;
+
+	/* if this field is still assigned it indicate that transfer related
+	 * with this request has not been finished yet. Driver in this
+	 * case simply allocate next request and assign flag REQUEST_INTERNAL_CH
+	 * flag to previous one. It will indicate that current request is
+	 * part of the previous one.
+	 */
+	if (priv_ep->descmis_req)
+		priv_ep->descmis_req->flags |= REQUEST_INTERNAL_CH;
+
+	priv_req->request.buf = kzalloc(CDNS3_DESCMIS_BUF_SIZE,
+					GFP_ATOMIC);
+	priv_ep->wa2_counter++;
+
+	if (!priv_req->request.buf) {
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+		goto err;
+	}
+
+	priv_req->request.length = CDNS3_DESCMIS_BUF_SIZE;
+	priv_ep->descmis_req = priv_req;
+
+	__cdns3_gadget_ep_queue(&priv_ep->endpoint,
+				&priv_ep->descmis_req->request,
+				GFP_ATOMIC);
+
+	return;
+
+err:
+	dev_err(priv_ep->cdns3_dev->dev,
+		"Failed: No sufficient memory for DESCMIS\n");
+}
+
+/**
+ * cdns3_gadget_giveback - call struct usb_request's ->complete callback
+ * @priv_ep: The endpoint to whom the request belongs to
+ * @priv_req: The request we're giving back
+ * @status: completion code for the request
+ *
+ * Must be called with controller's lock held and interrupts disabled. This
+ * function will unmap @req and call its ->complete() callback to notify upper
+ * layers that it has completed.
+ */
+void cdns3_gadget_giveback(struct cdns3_endpoint *priv_ep,
+			   struct cdns3_request *priv_req,
+			   int status)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct usb_request *request = &priv_req->request;
+
+	list_del_init(&request->list);
+
+	if (request->status == -EINPROGRESS)
+		request->status = status;
+
+	usb_gadget_unmap_request(&priv_dev->gadget, request,
+				 priv_ep->dir);
+
+	if ((priv_req->flags & REQUEST_UNALIGNED) &&
+	    priv_ep->dir == USB_DIR_OUT && !request->status)
+		memcpy(request->buf, priv_req->aligned_buf->buf,
+		       request->length);
+
+	priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
+	trace_cdns3_gadget_giveback(priv_req);
+
+	if (priv_dev->dev_ver < DEV_VER_V2) {
+		request = cdns3_wa2_gadget_giveback(priv_dev, priv_ep,
+						    priv_req);
+		if (!request)
+			return;
+	}
+
+	if (request->complete) {
+		spin_unlock(&priv_dev->lock);
+		usb_gadget_giveback_request(&priv_ep->endpoint,
+					    request);
+		spin_lock(&priv_dev->lock);
+	}
+
+	if (request->buf == priv_dev->zlp_buf)
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+}
+
+void cdns3_wa1_restore_cycle_bit(struct cdns3_endpoint *priv_ep)
+{
+	/* Work around for stale data address in TRB*/
+	if (priv_ep->wa1_set) {
+		trace_cdns3_wa1(priv_ep, "restore cycle bit");
+
+		priv_ep->wa1_set = 0;
+		priv_ep->wa1_trb_index = 0xFFFF;
+		if (priv_ep->wa1_cycle_bit) {
+			priv_ep->wa1_trb->control =
+				priv_ep->wa1_trb->control | 0x1;
+		} else {
+			priv_ep->wa1_trb->control =
+				priv_ep->wa1_trb->control & ~0x1;
+		}
+	}
+}
+
+static void cdns3_free_aligned_request_buf(struct cdns3_device *priv_dev)
+{
+	struct cdns3_aligned_buf *buf, *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	list_for_each_entry_safe(buf, tmp, &priv_dev->aligned_buf_list, list) {
+		if (!buf->in_use) {
+			list_del(&buf->list);
+
+			/*
+			 * Re-enable interrupts to free DMA capable memory.
+			 * Driver can't free this memory with disabled
+			 * interrupts.
+			 */
+			spin_unlock_irqrestore(&priv_dev->lock, flags);
+			dma_free_coherent(buf->buf);
+			kfree(buf);
+			spin_lock_irqsave(&priv_dev->lock, flags);
+		}
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+}
+
+static int cdns3_prepare_aligned_request_buf(struct cdns3_request *priv_req)
+{
+	struct cdns3_endpoint *priv_ep = priv_req->priv_ep;
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_aligned_buf *buf;
+
+	/* check if buffer is aligned to 8. */
+	if (!((uintptr_t)priv_req->request.buf & 0x7))
+		return 0;
+
+	buf = priv_req->aligned_buf;
+
+	if (!buf || priv_req->request.length > buf->size) {
+		buf = kzalloc(sizeof(*buf), GFP_ATOMIC);
+		if (!buf)
+			return -ENOMEM;
+
+		buf->size = priv_req->request.length;
+
+		buf->buf = dma_alloc_coherent(buf->size,
+					      (unsigned long *)&buf->dma);
+		if (!buf->buf) {
+			kfree(buf);
+			return -ENOMEM;
+		}
+
+		if (priv_req->aligned_buf) {
+			trace_cdns3_free_aligned_request(priv_req);
+			priv_req->aligned_buf->in_use = 0;
+#ifndef __UBOOT__
+			queue_work(system_freezable_wq,
+				   &priv_dev->aligned_buf_wq);
+#else
+			cdns3_free_aligned_request_buf(priv_dev);
+#endif
+		}
+
+		buf->in_use = 1;
+		priv_req->aligned_buf = buf;
+
+		list_add_tail(&buf->list,
+			      &priv_dev->aligned_buf_list);
+	}
+
+	if (priv_ep->dir == USB_DIR_IN) {
+		memcpy(buf->buf, priv_req->request.buf,
+		       priv_req->request.length);
+	}
+
+	priv_req->flags |= REQUEST_UNALIGNED;
+	trace_cdns3_prepare_aligned_request(priv_req);
+
+	return 0;
+}
+
+static int cdns3_wa1_update_guard(struct cdns3_endpoint *priv_ep,
+				  struct cdns3_trb *trb)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	if (!priv_ep->wa1_set) {
+		u32 doorbell;
+
+		doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+		if (doorbell) {
+			priv_ep->wa1_cycle_bit = priv_ep->pcs ? TRB_CYCLE : 0;
+			priv_ep->wa1_set = 1;
+			priv_ep->wa1_trb = trb;
+			priv_ep->wa1_trb_index = priv_ep->enqueue;
+			trace_cdns3_wa1(priv_ep, "set guard");
+			return 0;
+		}
+	}
+	return 1;
+}
+
+static void cdns3_wa1_tray_restore_cycle_bit(struct cdns3_device *priv_dev,
+					     struct cdns3_endpoint *priv_ep)
+{
+	int dma_index;
+	u32 doorbell;
+
+	doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+	dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+	if (!doorbell || dma_index != priv_ep->wa1_trb_index)
+		cdns3_wa1_restore_cycle_bit(priv_ep);
+}
+
+/**
+ * cdns3_ep_run_transfer - start transfer on no-default endpoint hardware
+ * @priv_ep: endpoint object
+ *
+ * Returns zero on success or negative value on failure
+ */
+int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+			  struct usb_request *request)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *trb;
+	dma_addr_t trb_dma;
+	u32 togle_pcs = 1;
+	int sg_iter = 0;
+	int num_trb = 1;
+	int address;
+	u32 control;
+	int pcs;
+
+	if (num_trb > priv_ep->free_trbs) {
+		priv_ep->flags |= EP_RING_FULL;
+		return -ENOBUFS;
+	}
+
+	priv_req = to_cdns3_request(request);
+	address = priv_ep->endpoint.desc->bEndpointAddress;
+
+	priv_ep->flags |= EP_PENDING_REQUEST;
+
+	/* must allocate buffer aligned to 8 */
+	if (priv_req->flags & REQUEST_UNALIGNED)
+		trb_dma = priv_req->aligned_buf->dma;
+	else
+		trb_dma = request->dma;
+
+	trb = priv_ep->trb_pool + priv_ep->enqueue;
+	priv_req->start_trb = priv_ep->enqueue;
+	priv_req->trb = trb;
+
+	cdns3_select_ep(priv_ep->cdns3_dev, address);
+
+	/* prepare ring */
+	if ((priv_ep->enqueue + num_trb)  >= (priv_ep->num_trbs - 1)) {
+		struct cdns3_trb *link_trb;
+		int doorbell, dma_index;
+		u32 ch_bit = 0;
+
+		doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+		dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+		/* Driver can't update LINK TRB if it is current processed. */
+		if (doorbell && dma_index == priv_ep->num_trbs - 1) {
+			priv_ep->flags |= EP_DEFERRED_DRDY;
+			return -ENOBUFS;
+		}
+
+		/*updating C bt in  Link TRB before starting DMA*/
+		link_trb = priv_ep->trb_pool + (priv_ep->num_trbs - 1);
+		/*
+		 * For TRs size equal 2 enabling TRB_CHAIN for epXin causes
+		 * that DMA stuck at the LINK TRB.
+		 * On the other hand, removing TRB_CHAIN for longer TRs for
+		 * epXout cause that DMA stuck after handling LINK TRB.
+		 * To eliminate this strange behavioral driver set TRB_CHAIN
+		 * bit only for TR size > 2.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC ||
+		    TRBS_PER_SEGMENT > 2)
+			ch_bit = TRB_CHAIN;
+
+		link_trb->control = ((priv_ep->pcs) ? TRB_CYCLE : 0) |
+				    TRB_TYPE(TRB_LINK) | TRB_TOGGLE | ch_bit;
+	}
+
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		togle_pcs = cdns3_wa1_update_guard(priv_ep, trb);
+
+	/* set incorrect Cycle Bit for first trb*/
+	control = priv_ep->pcs ? 0 : TRB_CYCLE;
+
+	do {
+		u32 length;
+		u16 td_size = 0;
+
+		/* fill TRB */
+		control |= TRB_TYPE(TRB_NORMAL);
+		trb->buffer = TRB_BUFFER(trb_dma);
+
+		length = request->length;
+
+		if (likely(priv_dev->dev_ver >= DEV_VER_V2))
+			td_size = DIV_ROUND_UP(length,
+					       priv_ep->endpoint.maxpacket);
+
+		trb->length = TRB_BURST_LEN(priv_ep->trb_burst_size) |
+					TRB_LEN(length);
+		if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+			trb->length |= TRB_TDL_SS_SIZE(td_size);
+		else
+			control |= TRB_TDL_HS_SIZE(td_size);
+
+		pcs = priv_ep->pcs ? TRB_CYCLE : 0;
+
+		/*
+		 * first trb should be prepared as last to avoid processing
+		 *  transfer to early
+		 */
+		if (sg_iter != 0)
+			control |= pcs;
+
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir) {
+			control |= TRB_IOC | TRB_ISP;
+		} else {
+			/* for last element in TD or in SG list */
+			if (sg_iter == (num_trb - 1) && sg_iter != 0)
+				control |= pcs | TRB_IOC | TRB_ISP;
+		}
+
+		if (sg_iter)
+			trb->control = control;
+		else
+			priv_req->trb->control = control;
+
+		control = 0;
+		++sg_iter;
+		priv_req->end_trb = priv_ep->enqueue;
+		cdns3_ep_inc_enq(priv_ep);
+		trb = priv_ep->trb_pool + priv_ep->enqueue;
+	} while (sg_iter < num_trb);
+
+	trb = priv_req->trb;
+
+	priv_req->flags |= REQUEST_PENDING;
+
+	if (sg_iter == 1)
+		trb->control |= TRB_IOC | TRB_ISP;
+
+	/*
+	 * Memory barrier - cycle bit must be set before other filds in trb.
+	 */
+	dmb();
+
+	/* give the TD to the consumer*/
+	if (togle_pcs)
+		trb->control =  trb->control ^ 1;
+
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		cdns3_wa1_tray_restore_cycle_bit(priv_dev, priv_ep);
+
+	trace_cdns3_prepare_trb(priv_ep, priv_req->trb);
+
+	/*
+	 * Memory barrier - Cycle Bit must be set before trb->length  and
+	 * trb->buffer fields.
+	 */
+	dmb();
+
+	/*
+	 * For DMULT mode we can set address to transfer ring only once after
+	 * enabling endpoint.
+	 */
+	if (priv_ep->flags & EP_UPDATE_EP_TRBADDR) {
+		/*
+		 * Until SW is not ready to handle the OUT transfer the ISO OUT
+		 * Endpoint should be disabled (EP_CFG.ENABLE = 0).
+		 * EP_CFG_ENABLE must be set before updating ep_traddr.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir &&
+		    !(priv_ep->flags & EP_QUIRK_ISO_OUT_EN)) {
+			priv_ep->flags |= EP_QUIRK_ISO_OUT_EN;
+			cdns3_set_register_bit(&priv_dev->regs->ep_cfg,
+					       EP_CFG_ENABLE);
+		}
+
+		writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma +
+					priv_req->start_trb * TRB_SIZE),
+					&priv_dev->regs->ep_traddr);
+
+		priv_ep->flags &= ~EP_UPDATE_EP_TRBADDR;
+	}
+
+	if (!priv_ep->wa1_set && !(priv_ep->flags & EP_STALLED)) {
+		trace_cdns3_ring(priv_ep);
+		/*clearing TRBERR and EP_STS_DESCMIS before seting DRDY*/
+		writel(EP_STS_TRBERR | EP_STS_DESCMIS, &priv_dev->regs->ep_sts);
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+		trace_cdns3_doorbell_epx(priv_ep->name,
+					 readl(&priv_dev->regs->ep_traddr));
+	}
+
+	/* WORKAROUND for transition to L0 */
+	__cdns3_gadget_wakeup(priv_dev);
+
+	return 0;
+}
+
+void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct usb_ep *ep;
+	int val;
+
+	if (priv_dev->hw_configured_flag)
+		return;
+
+	writel(USB_CONF_CFGSET, &priv_dev->regs->usb_conf);
+	writel(EP_CMD_ERDY | EP_CMD_REQ_CMPL, &priv_dev->regs->ep_cmd);
+
+	cdns3_set_register_bit(&priv_dev->regs->usb_conf,
+			       USB_CONF_U1EN | USB_CONF_U2EN);
+
+	/* wait until configuration set */
+	readl_poll_timeout_atomic(&priv_dev->regs->usb_sts, val,
+				  val & USB_STS_CFGSTS_MASK, 100);
+
+	priv_dev->hw_configured_flag = 1;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		priv_ep = ep_to_cdns3_ep(ep);
+		if (priv_ep->flags & EP_ENABLED)
+			cdns3_start_all_request(priv_dev, priv_ep);
+	}
+}
+
+/**
+ * cdns3_request_handled - check whether request has been handled by DMA
+ *
+ * @priv_ep: extended endpoint object.
+ * @priv_req: request object for checking
+ *
+ * Endpoint must be selected before invoking this function.
+ *
+ * Returns false if request has not been handled by DMA, else returns true.
+ *
+ * SR - start ring
+ * ER -  end ring
+ * DQ = priv_ep->dequeue - dequeue position
+ * EQ = priv_ep->enqueue -  enqueue position
+ * ST = priv_req->start_trb - index of first TRB in transfer ring
+ * ET = priv_req->end_trb - index of last TRB in transfer ring
+ * CI = current_index - index of processed TRB by DMA.
+ *
+ * As first step, function checks if cycle bit for priv_req->start_trb is
+ * correct.
+ *
+ * some rules:
+ * 1. priv_ep->dequeue never exceed current_index.
+ * 2  priv_ep->enqueue never exceed priv_ep->dequeue
+ * 3. exception: priv_ep->enqueue == priv_ep->dequeue
+ *    and priv_ep->free_trbs is zero.
+ *    This case indicate that TR is full.
+ *
+ * Then We can split recognition into two parts:
+ * Case 1 - priv_ep->dequeue < current_index
+ *      SR ... EQ ... DQ ... CI ... ER
+ *      SR ... DQ ... CI ... EQ ... ER
+ *
+ *      Request has been handled by DMA if ST and ET is between DQ and CI.
+ *
+ * Case 2 - priv_ep->dequeue > current_index
+ * This situation take place when CI go through the LINK TRB at the end of
+ * transfer ring.
+ *      SR ... CI ... EQ ... DQ ... ER
+ *
+ *      Request has been handled by DMA if ET is less then CI or
+ *      ET is greater or equal DQ.
+ */
+static bool cdns3_request_handled(struct cdns3_endpoint *priv_ep,
+				  struct cdns3_request *priv_req)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_trb *trb = priv_req->trb;
+	int current_index = 0;
+	int handled = 0;
+	int doorbell;
+
+	current_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+	doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+	trb = &priv_ep->trb_pool[priv_req->start_trb];
+
+	if ((trb->control  & TRB_CYCLE) != priv_ep->ccs)
+		goto finish;
+
+	if (doorbell == 1 && current_index == priv_ep->dequeue)
+		goto finish;
+
+	/* The corner case for TRBS_PER_SEGMENT equal 2). */
+	if (TRBS_PER_SEGMENT == 2 && priv_ep->type != USB_ENDPOINT_XFER_ISOC) {
+		handled = 1;
+		goto finish;
+	}
+
+	if (priv_ep->enqueue == priv_ep->dequeue &&
+	    priv_ep->free_trbs == 0) {
+		handled = 1;
+	} else if (priv_ep->dequeue < current_index) {
+		if ((current_index == (priv_ep->num_trbs - 1)) &&
+		    !priv_ep->dequeue)
+			goto finish;
+
+		if (priv_req->end_trb >= priv_ep->dequeue &&
+		    priv_req->end_trb < current_index)
+			handled = 1;
+	} else if (priv_ep->dequeue  > current_index) {
+		if (priv_req->end_trb  < current_index ||
+		    priv_req->end_trb >= priv_ep->dequeue)
+			handled = 1;
+	}
+
+finish:
+	trace_cdns3_request_handled(priv_req, current_index, handled);
+
+	return handled;
+}
+
+static void cdns3_transfer_completed(struct cdns3_device *priv_dev,
+				     struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+	struct usb_request *request;
+	struct cdns3_trb *trb;
+
+	while (!list_empty(&priv_ep->pending_req_list)) {
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+		priv_req = to_cdns3_request(request);
+
+		/* Re-select endpoint. It could be changed by other CPU during
+		 * handling usb_gadget_giveback_request.
+		 */
+#ifndef __UBOOT__
+		cdns3_select_ep(priv_dev, priv_ep->endpoint.address);
+#else
+		cdns3_select_ep(priv_dev,
+				priv_ep->endpoint.desc->bEndpointAddress);
+#endif
+
+		if (!cdns3_request_handled(priv_ep, priv_req))
+			goto prepare_next_td;
+
+		trb = priv_ep->trb_pool + priv_ep->dequeue;
+		trace_cdns3_complete_trb(priv_ep, trb);
+
+		if (trb != priv_req->trb)
+			dev_warn(priv_dev->dev,
+				 "request_trb=0x%p, queue_trb=0x%p\n",
+				 priv_req->trb, trb);
+
+		request->actual = TRB_LEN(le32_to_cpu(trb->length));
+		cdns3_move_deq_to_next_trb(priv_req);
+		cdns3_gadget_giveback(priv_ep, priv_req, 0);
+
+		if (priv_ep->type != USB_ENDPOINT_XFER_ISOC &&
+		    TRBS_PER_SEGMENT == 2)
+			break;
+	}
+	priv_ep->flags &= ~EP_PENDING_REQUEST;
+
+prepare_next_td:
+	if (!(priv_ep->flags & EP_STALLED) &&
+	    !(priv_ep->flags & EP_STALL_PENDING))
+		cdns3_start_all_request(priv_dev, priv_ep);
+}
+
+void cdns3_rearm_transfer(struct cdns3_endpoint *priv_ep, u8 rearm)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	cdns3_wa1_restore_cycle_bit(priv_ep);
+
+	if (rearm) {
+		trace_cdns3_ring(priv_ep);
+
+		/* Cycle Bit must be updated before arming DMA. */
+		dmb();
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+
+		__cdns3_gadget_wakeup(priv_dev);
+
+		trace_cdns3_doorbell_epx(priv_ep->name,
+					 readl(&priv_dev->regs->ep_traddr));
+	}
+}
+
+/**
+ * cdns3_check_ep_interrupt_proceed - Processes interrupt related to endpoint
+ * @priv_ep: endpoint object
+ *
+ * Returns 0
+ */
+static int cdns3_check_ep_interrupt_proceed(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	u32 ep_sts_reg;
+
+#ifndef __UBOOT__
+	cdns3_select_ep(priv_dev, priv_ep->endpoint.address);
+#else
+	cdns3_select_ep(priv_dev, priv_ep->endpoint.desc->bEndpointAddress);
+#endif
+
+	trace_cdns3_epx_irq(priv_dev, priv_ep);
+
+	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+	writel(ep_sts_reg, &priv_dev->regs->ep_sts);
+
+	if (ep_sts_reg & EP_STS_TRBERR) {
+		if (priv_ep->flags & EP_STALL_PENDING &&
+		    !(ep_sts_reg & EP_STS_DESCMIS &&
+		    priv_dev->dev_ver < DEV_VER_V2)) {
+			cdns3_ep_stall_flush(priv_ep);
+		}
+
+		/*
+		 * For isochronous transfer driver completes request on
+		 * IOC or on TRBERR. IOC appears only when device receive
+		 * OUT data packet. If host disable stream or lost some packet
+		 * then the only way to finish all queued transfer is to do it
+		 * on TRBERR event.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC &&
+		    !priv_ep->wa1_set) {
+			if (!priv_ep->dir) {
+				u32 ep_cfg = readl(&priv_dev->regs->ep_cfg);
+
+				ep_cfg &= ~EP_CFG_ENABLE;
+				writel(ep_cfg, &priv_dev->regs->ep_cfg);
+				priv_ep->flags &= ~EP_QUIRK_ISO_OUT_EN;
+			}
+			cdns3_transfer_completed(priv_dev, priv_ep);
+		} else if (!(priv_ep->flags & EP_STALLED) &&
+			  !(priv_ep->flags & EP_STALL_PENDING)) {
+			if (priv_ep->flags & EP_DEFERRED_DRDY) {
+				priv_ep->flags &= ~EP_DEFERRED_DRDY;
+				cdns3_start_all_request(priv_dev, priv_ep);
+			} else {
+				cdns3_rearm_transfer(priv_ep,
+						     priv_ep->wa1_set);
+			}
+		}
+	}
+
+	if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP)) {
+		if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+			if (ep_sts_reg & EP_STS_ISP)
+				priv_ep->flags |= EP_QUIRK_END_TRANSFER;
+			else
+				priv_ep->flags &= ~EP_QUIRK_END_TRANSFER;
+		}
+
+		cdns3_transfer_completed(priv_dev, priv_ep);
+	}
+
+	/*
+	 * WA2: this condition should only be meet when
+	 * priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET or
+	 * priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN.
+	 * In other cases this interrupt will be disabled/
+	 */
+	if (ep_sts_reg & EP_STS_DESCMIS && priv_dev->dev_ver < DEV_VER_V2 &&
+	    !(priv_ep->flags & EP_STALLED))
+		cdns3_wa2_descmissing_packet(priv_ep);
+
+	return 0;
+}
+
+static void cdns3_disconnect_gadget(struct cdns3_device *priv_dev)
+{
+	if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect) {
+		spin_unlock(&priv_dev->lock);
+		priv_dev->gadget_driver->disconnect(&priv_dev->gadget);
+		spin_lock(&priv_dev->lock);
+	}
+}
+
+/**
+ * cdns3_check_usb_interrupt_proceed - Processes interrupt related to device
+ * @priv_dev: extended gadget object
+ * @usb_ists: bitmap representation of device's reported interrupts
+ * (usb_ists register value)
+ */
+static void cdns3_check_usb_interrupt_proceed(struct cdns3_device *priv_dev,
+					      u32 usb_ists)
+{
+	int speed = 0;
+
+	trace_cdns3_usb_irq(priv_dev, usb_ists);
+	if (usb_ists & USB_ISTS_L1ENTI) {
+		/*
+		 * WORKAROUND: CDNS3 controller has issue with hardware resuming
+		 * from L1. To fix it, if any DMA transfer is pending driver
+		 * must starts driving resume signal immediately.
+		 */
+		if (readl(&priv_dev->regs->drbl))
+			__cdns3_gadget_wakeup(priv_dev);
+	}
+
+	/* Connection detected */
+	if (usb_ists & (USB_ISTS_CON2I | USB_ISTS_CONI)) {
+		speed = cdns3_get_speed(priv_dev);
+		priv_dev->gadget.speed = speed;
+		usb_gadget_set_state(&priv_dev->gadget, USB_STATE_POWERED);
+		cdns3_ep0_config(priv_dev);
+	}
+
+	/* Disconnection detected */
+	if (usb_ists & (USB_ISTS_DIS2I | USB_ISTS_DISI)) {
+		cdns3_disconnect_gadget(priv_dev);
+		priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+		usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
+		cdns3_hw_reset_eps_config(priv_dev);
+	}
+
+	if (usb_ists & (USB_ISTS_L2ENTI | USB_ISTS_U3ENTI)) {
+		if (priv_dev->gadget_driver &&
+		    priv_dev->gadget_driver->suspend) {
+			spin_unlock(&priv_dev->lock);
+			priv_dev->gadget_driver->suspend(&priv_dev->gadget);
+			spin_lock(&priv_dev->lock);
+		}
+	}
+
+	if (usb_ists & (USB_ISTS_L2EXTI | USB_ISTS_U3EXTI)) {
+		if (priv_dev->gadget_driver &&
+		    priv_dev->gadget_driver->resume) {
+			spin_unlock(&priv_dev->lock);
+			priv_dev->gadget_driver->resume(&priv_dev->gadget);
+			spin_lock(&priv_dev->lock);
+		}
+	}
+
+	/* reset*/
+	if (usb_ists & (USB_ISTS_UWRESI | USB_ISTS_UHRESI | USB_ISTS_U2RESI)) {
+		if (priv_dev->gadget_driver) {
+			spin_unlock(&priv_dev->lock);
+			usb_gadget_udc_reset(&priv_dev->gadget,
+					     priv_dev->gadget_driver);
+			spin_lock(&priv_dev->lock);
+
+			/*read again to check the actual speed*/
+			speed = cdns3_get_speed(priv_dev);
+			priv_dev->gadget.speed = speed;
+			cdns3_hw_reset_eps_config(priv_dev);
+			cdns3_ep0_config(priv_dev);
+		}
+	}
+}
+
+/**
+ * cdns3_device_irq_handler- interrupt handler for device part of controller
+ *
+ * @irq: irq number for cdns3 core device
+ * @data: structure of cdns3
+ *
+ * Returns IRQ_HANDLED or IRQ_NONE
+ */
+static irqreturn_t cdns3_device_irq_handler(int irq, void *data)
+{
+	struct cdns3_device *priv_dev;
+	struct cdns3 *cdns = data;
+	irqreturn_t ret = IRQ_NONE;
+	u32 reg;
+
+	priv_dev = cdns->gadget_dev;
+
+	/* check USB device interrupt */
+	reg = readl(&priv_dev->regs->usb_ists);
+	if (reg) {
+		/* After masking interrupts the new interrupts won't be
+		 * reported in usb_ists/ep_ists. In order to not lose some
+		 * of them driver disables only detected interrupts.
+		 * They will be enabled ASAP after clearing source of
+		 * interrupt. This an unusual behavior only applies to
+		 * usb_ists register.
+		 */
+		reg = ~reg & readl(&priv_dev->regs->usb_ien);
+		/* mask deferred interrupt. */
+		writel(reg, &priv_dev->regs->usb_ien);
+		ret = IRQ_WAKE_THREAD;
+	}
+
+	/* check endpoint interrupt */
+	reg = readl(&priv_dev->regs->ep_ists);
+	if (reg) {
+		writel(0, &priv_dev->regs->ep_ien);
+		ret = IRQ_WAKE_THREAD;
+	}
+
+	return ret;
+}
+
+/**
+ * cdns3_device_thread_irq_handler- interrupt handler for device part
+ * of controller
+ *
+ * @irq: irq number for cdns3 core device
+ * @data: structure of cdns3
+ *
+ * Returns IRQ_HANDLED or IRQ_NONE
+ */
+static irqreturn_t cdns3_device_thread_irq_handler(int irq, void *data)
+{
+	struct cdns3_device *priv_dev;
+	struct cdns3 *cdns = data;
+	irqreturn_t ret = IRQ_NONE;
+	unsigned long flags;
+	int bit;
+	u32 reg;
+
+	priv_dev = cdns->gadget_dev;
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	reg = readl(&priv_dev->regs->usb_ists);
+	if (reg) {
+		writel(reg, &priv_dev->regs->usb_ists);
+		writel(USB_IEN_INIT, &priv_dev->regs->usb_ien);
+		cdns3_check_usb_interrupt_proceed(priv_dev, reg);
+		ret = IRQ_HANDLED;
+	}
+
+	reg = readl(&priv_dev->regs->ep_ists);
+
+	/* handle default endpoint OUT */
+	if (reg & EP_ISTS_EP_OUT0) {
+		cdns3_check_ep0_interrupt_proceed(priv_dev, USB_DIR_OUT);
+		ret = IRQ_HANDLED;
+	}
+
+	/* handle default endpoint IN */
+	if (reg & EP_ISTS_EP_IN0) {
+		cdns3_check_ep0_interrupt_proceed(priv_dev, USB_DIR_IN);
+		ret = IRQ_HANDLED;
+	}
+
+	/* check if interrupt from non default endpoint, if no exit */
+	reg &= ~(EP_ISTS_EP_OUT0 | EP_ISTS_EP_IN0);
+	if (!reg)
+		goto irqend;
+
+	for_each_set_bit(bit, (unsigned long *)&reg,
+			 sizeof(u32) * BITS_PER_BYTE) {
+		cdns3_check_ep_interrupt_proceed(priv_dev->eps[bit]);
+		ret = IRQ_HANDLED;
+	}
+
+irqend:
+	writel(~0, &priv_dev->regs->ep_ien);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_ep_onchip_buffer_reserve - Try to reserve onchip buf for EP
+ *
+ * The real reservation will occur during write to EP_CFG register,
+ * this function is used to check if the 'size' reservation is allowed.
+ *
+ * @priv_dev: extended gadget object
+ * @size: the size (KB) for EP would like to allocate
+ * @is_in: endpoint direction
+ *
+ * Return 0 if the required size can met or negative value on failure
+ */
+static int cdns3_ep_onchip_buffer_reserve(struct cdns3_device *priv_dev,
+					  int size, int is_in)
+{
+	int remained;
+
+	/* 2KB are reserved for EP0*/
+	remained = priv_dev->onchip_buffers - priv_dev->onchip_used_size - 2;
+
+	if (is_in) {
+		if (remained < size)
+			return -EPERM;
+
+		priv_dev->onchip_used_size += size;
+	} else {
+		int required;
+
+		/**
+		 *  ALL OUT EPs are shared the same chunk onchip memory, so
+		 * driver checks if it already has assigned enough buffers
+		 */
+		if (priv_dev->out_mem_is_allocated >= size)
+			return 0;
+
+		required = size - priv_dev->out_mem_is_allocated;
+
+		if (required > remained)
+			return -EPERM;
+
+		priv_dev->out_mem_is_allocated += required;
+		priv_dev->onchip_used_size += required;
+	}
+
+	return 0;
+}
+
+void cdns3_configure_dmult(struct cdns3_device *priv_dev,
+			   struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+
+	/* For dev_ver > DEV_VER_V2 DMULT is configured per endpoint */
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		writel(USB_CONF_DMULT, &regs->usb_conf);
+
+	if (priv_dev->dev_ver == DEV_VER_V2)
+		writel(USB_CONF2_EN_TDL_TRB, &regs->usb_conf2);
+
+	if (priv_dev->dev_ver >= DEV_VER_V3 && priv_ep) {
+		u32 mask;
+
+		if (priv_ep->dir)
+			mask = BIT(priv_ep->num + 16);
+		else
+			mask = BIT(priv_ep->num);
+
+		if (priv_ep->type != USB_ENDPOINT_XFER_ISOC) {
+			cdns3_set_register_bit(&regs->tdl_from_trb, mask);
+			cdns3_set_register_bit(&regs->tdl_beh, mask);
+			cdns3_set_register_bit(&regs->tdl_beh2, mask);
+			cdns3_set_register_bit(&regs->dma_adv_td, mask);
+		}
+
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC && !priv_ep->dir)
+			cdns3_set_register_bit(&regs->tdl_from_trb, mask);
+
+		cdns3_set_register_bit(&regs->dtrans, mask);
+	}
+}
+
+/**
+ * cdns3_ep_config Configure hardware endpoint
+ * @priv_ep: extended endpoint object
+ */
+void cdns3_ep_config(struct cdns3_endpoint *priv_ep)
+{
+	bool is_iso_ep = (priv_ep->type == USB_ENDPOINT_XFER_ISOC);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	u32 bEndpointAddress = priv_ep->num | priv_ep->dir;
+	u32 max_packet_size = 0;
+	u8 maxburst = 0;
+	u32 ep_cfg = 0;
+	u8 buffering;
+	u8 mult = 0;
+	int ret;
+
+	buffering = CDNS3_EP_BUF_SIZE - 1;
+
+	cdns3_configure_dmult(priv_dev, priv_ep);
+
+	switch (priv_ep->type) {
+	case USB_ENDPOINT_XFER_INT:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_INT);
+
+		if ((priv_dev->dev_ver == DEV_VER_V2 && !priv_ep->dir) ||
+		    priv_dev->dev_ver > DEV_VER_V2)
+			ep_cfg |= EP_CFG_TDL_CHK;
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_BULK);
+
+		if ((priv_dev->dev_ver == DEV_VER_V2  && !priv_ep->dir) ||
+		    priv_dev->dev_ver > DEV_VER_V2)
+			ep_cfg |= EP_CFG_TDL_CHK;
+		break;
+	default:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_ISOC);
+		mult = CDNS3_EP_ISO_HS_MULT - 1;
+		buffering = mult + 1;
+	}
+
+	switch (priv_dev->gadget.speed) {
+	case USB_SPEED_FULL:
+		max_packet_size = is_iso_ep ? 1023 : 64;
+		break;
+	case USB_SPEED_HIGH:
+		max_packet_size = is_iso_ep ? 1024 : 512;
+		break;
+	case USB_SPEED_SUPER:
+		/* It's limitation that driver assumes in driver. */
+		mult = 0;
+		max_packet_size = 1024;
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC) {
+			maxburst = CDNS3_EP_ISO_SS_BURST - 1;
+			buffering = (mult + 1) *
+				    (maxburst + 1);
+
+			if (priv_ep->interval > 1)
+				buffering++;
+		} else {
+			maxburst = CDNS3_EP_BUF_SIZE - 1;
+		}
+		break;
+	default:
+		/* all other speed are not supported */
+		return;
+	}
+
+	if (max_packet_size == 1024)
+		priv_ep->trb_burst_size = 128;
+	else if (max_packet_size >= 512)
+		priv_ep->trb_burst_size = 64;
+	else
+		priv_ep->trb_burst_size = 16;
+
+	ret = cdns3_ep_onchip_buffer_reserve(priv_dev, buffering + 1,
+					     !!priv_ep->dir);
+	if (ret) {
+		dev_err(priv_dev->dev, "onchip mem is full, ep is invalid\n");
+		return;
+	}
+
+	ep_cfg |= EP_CFG_MAXPKTSIZE(max_packet_size) |
+		  EP_CFG_MULT(mult) |
+		  EP_CFG_BUFFERING(buffering) |
+		  EP_CFG_MAXBURST(maxburst);
+
+	cdns3_select_ep(priv_dev, bEndpointAddress);
+	writel(ep_cfg, &priv_dev->regs->ep_cfg);
+
+	dev_dbg(priv_dev->dev, "Configure %s: with val %08x\n",
+		priv_ep->name, ep_cfg);
+}
+
+/* Find correct direction for HW endpoint according to description */
+static int cdns3_ep_dir_is_correct(struct usb_endpoint_descriptor *desc,
+				   struct cdns3_endpoint *priv_ep)
+{
+	return (priv_ep->endpoint.caps.dir_in && usb_endpoint_dir_in(desc)) ||
+	       (priv_ep->endpoint.caps.dir_out && usb_endpoint_dir_out(desc));
+}
+
+static struct
+cdns3_endpoint *cdns3_find_available_ep(struct cdns3_device *priv_dev,
+					struct usb_endpoint_descriptor *desc)
+{
+	struct usb_ep *ep;
+	struct cdns3_endpoint *priv_ep;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		unsigned long num;
+		/* ep name pattern likes epXin or epXout */
+		char c[2] = {ep->name[2], '\0'};
+
+		num = simple_strtoul(c, NULL, 10);
+
+		priv_ep = ep_to_cdns3_ep(ep);
+		if (cdns3_ep_dir_is_correct(desc, priv_ep)) {
+			if (!(priv_ep->flags & EP_CLAIMED)) {
+				priv_ep->num  = num;
+				return priv_ep;
+			}
+		}
+	}
+
+	return ERR_PTR(-ENOENT);
+}
+
+/*
+ *  Cadence IP has one limitation that all endpoints must be configured
+ * (Type & MaxPacketSize) before setting configuration through hardware
+ * register, it means we can't change endpoints configuration after
+ * set_configuration.
+ *
+ * This function set EP_CLAIMED flag which is added when the gadget driver
+ * uses usb_ep_autoconfig to configure specific endpoint;
+ * When the udc driver receives set_configurion request,
+ * it goes through all claimed endpoints, and configure all endpoints
+ * accordingly.
+ *
+ * At usb_ep_ops.enable/disable, we only enable and disable endpoint through
+ * ep_cfg register which can be changed after set_configuration, and do
+ * some software operation accordingly.
+ */
+static struct
+usb_ep *cdns3_gadget_match_ep(struct usb_gadget *gadget,
+			      struct usb_endpoint_descriptor *desc,
+			      struct usb_ss_ep_comp_descriptor *comp_desc)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct cdns3_endpoint *priv_ep;
+	unsigned long flags;
+
+	priv_ep = cdns3_find_available_ep(priv_dev, desc);
+	if (IS_ERR(priv_ep)) {
+		dev_err(priv_dev->dev, "no available ep\n");
+		return NULL;
+	}
+
+	dev_dbg(priv_dev->dev, "match endpoint: %s\n", priv_ep->name);
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_ep->endpoint.desc = desc;
+	priv_ep->dir  = usb_endpoint_dir_in(desc) ? USB_DIR_IN : USB_DIR_OUT;
+	priv_ep->type = usb_endpoint_type(desc);
+	priv_ep->flags |= EP_CLAIMED;
+	priv_ep->interval = desc->bInterval ? BIT(desc->bInterval - 1) : 0;
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return &priv_ep->endpoint;
+}
+
+/**
+ * cdns3_gadget_ep_alloc_request Allocates request
+ * @ep: endpoint object associated with request
+ * @gfp_flags: gfp flags
+ *
+ * Returns allocated request address, NULL on allocation error
+ */
+struct usb_request *cdns3_gadget_ep_alloc_request(struct usb_ep *ep,
+						  gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_request *priv_req;
+
+	priv_req = kzalloc(sizeof(*priv_req), gfp_flags);
+	if (!priv_req)
+		return NULL;
+
+	priv_req->priv_ep = priv_ep;
+
+	trace_cdns3_alloc_request(priv_req);
+	return &priv_req->request;
+}
+
+/**
+ * cdns3_gadget_ep_free_request Free memory occupied by request
+ * @ep: endpoint object associated with request
+ * @request: request to free memory
+ */
+void cdns3_gadget_ep_free_request(struct usb_ep *ep,
+				  struct usb_request *request)
+{
+	struct cdns3_request *priv_req = to_cdns3_request(request);
+
+	if (priv_req->aligned_buf)
+		priv_req->aligned_buf->in_use = 0;
+
+	trace_cdns3_free_request(priv_req);
+	kfree(priv_req);
+}
+
+/**
+ * cdns3_gadget_ep_enable Enable endpoint
+ * @ep: endpoint object
+ * @desc: endpoint descriptor
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep_enable(struct usb_ep *ep,
+				  const struct usb_endpoint_descriptor *desc)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_device *priv_dev;
+	u32 reg = EP_STS_EN_TRBERREN;
+	u32 bEndpointAddress;
+	unsigned long flags;
+	int enable = 1;
+	int ret;
+	int val;
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+
+	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
+		dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
+		return -EINVAL;
+	}
+
+	if (!desc->wMaxPacketSize) {
+		dev_err(priv_dev->dev, "usbss: missing wMaxPacketSize\n");
+		return -EINVAL;
+	}
+
+	if (WARN_ON(priv_ep->flags & EP_ENABLED))
+		return 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	priv_ep->endpoint.desc = desc;
+	priv_ep->type = usb_endpoint_type(desc);
+	priv_ep->interval = desc->bInterval ? BIT(desc->bInterval - 1) : 0;
+
+	if (priv_ep->interval > ISO_MAX_INTERVAL &&
+	    priv_ep->type == USB_ENDPOINT_XFER_ISOC) {
+		dev_err(priv_dev->dev, "Driver is limited to %d period\n",
+			ISO_MAX_INTERVAL);
+
+		ret =  -EINVAL;
+		goto exit;
+	}
+
+	ret = cdns3_allocate_trb_pool(priv_ep);
+
+	if (ret)
+		goto exit;
+
+	bEndpointAddress = priv_ep->num | priv_ep->dir;
+	cdns3_select_ep(priv_dev, bEndpointAddress);
+
+	trace_cdns3_gadget_ep_enable(priv_ep);
+
+	writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	ret = readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+					!(val & (EP_CMD_CSTALL | EP_CMD_EPRST)),
+					1000);
+
+	if (unlikely(ret)) {
+		cdns3_free_trb_pool(priv_ep);
+		ret =  -EINVAL;
+		goto exit;
+	}
+
+	/* enable interrupt for selected endpoint */
+	cdns3_set_register_bit(&priv_dev->regs->ep_ien,
+			       BIT(cdns3_ep_addr_to_index(bEndpointAddress)));
+
+	if (priv_dev->dev_ver < DEV_VER_V2)
+		cdns3_wa2_enable_detection(priv_dev, priv_ep, reg);
+
+	writel(reg, &priv_dev->regs->ep_sts_en);
+
+	/*
+	 * For some versions of controller at some point during ISO OUT traffic
+	 * DMA reads Transfer Ring for the EP which has never got doorbell.
+	 * This issue was detected only on simulation, but to avoid this issue
+	 * driver add protection against it. To fix it driver enable ISO OUT
+	 * endpoint before setting DRBL. This special treatment of ISO OUT
+	 * endpoints are recommended by controller specification.
+	 */
+	if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir)
+		enable = 0;
+
+	if (enable)
+		cdns3_set_register_bit(&priv_dev->regs->ep_cfg, EP_CFG_ENABLE);
+
+	ep->desc = desc;
+	priv_ep->flags &= ~(EP_PENDING_REQUEST | EP_STALLED | EP_STALL_PENDING |
+			    EP_QUIRK_ISO_OUT_EN | EP_QUIRK_EXTRA_BUF_EN);
+	priv_ep->flags |= EP_ENABLED | EP_UPDATE_EP_TRBADDR;
+	priv_ep->wa1_set = 0;
+	priv_ep->enqueue = 0;
+	priv_ep->dequeue = 0;
+	reg = readl(&priv_dev->regs->ep_sts);
+	priv_ep->pcs = !!EP_STS_CCS(reg);
+	priv_ep->ccs = !!EP_STS_CCS(reg);
+	/* one TRB is reserved for link TRB used in DMULT mode*/
+	priv_ep->free_trbs = priv_ep->num_trbs - 1;
+exit:
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_disable Disable endpoint
+ * @ep: endpoint object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep_disable(struct usb_ep *ep)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_request *priv_req;
+	struct cdns3_device *priv_dev;
+	struct usb_request *request;
+	unsigned long flags;
+	int ret = 0;
+	u32 ep_cfg;
+	int val;
+
+	if (!ep) {
+		pr_err("usbss: invalid parameters\n");
+		return -EINVAL;
+	}
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+
+	if (WARN_ON(!(priv_ep->flags & EP_ENABLED)))
+		return 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	trace_cdns3_gadget_ep_disable(priv_ep);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	ep_cfg = readl(&priv_dev->regs->ep_cfg);
+	ep_cfg &= ~EP_CFG_ENABLE;
+	writel(ep_cfg, &priv_dev->regs->ep_cfg);
+
+	/**
+	 * Driver needs some time before resetting endpoint.
+	 * It need waits for clearing DBUSY bit or for timeout expired.
+	 * 10us is enough time for controller to stop transfer.
+	 */
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_sts, val,
+				  !(val & EP_STS_DBUSY), 10);
+	writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+				  !(val & (EP_CMD_CSTALL | EP_CMD_EPRST)),
+				  1000);
+	if (unlikely(ret))
+		dev_err(priv_dev->dev, "Timeout: %s resetting failed.\n",
+			priv_ep->name);
+
+	while (!list_empty(&priv_ep->pending_req_list)) {
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
+				      -ESHUTDOWN);
+	}
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+
+		kfree(priv_req->request.buf);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+					     &priv_req->request);
+		list_del_init(&priv_req->list);
+		--priv_ep->wa2_counter;
+	}
+
+	while (!list_empty(&priv_ep->deferred_req_list)) {
+		request = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
+				      -ESHUTDOWN);
+	}
+
+	priv_ep->descmis_req = NULL;
+
+	ep->desc = NULL;
+	priv_ep->flags &= ~EP_ENABLED;
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_queue Transfer data on endpoint
+ * @ep: endpoint object
+ * @request: request object
+ * @gfp_flags: gfp flags
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int __cdns3_gadget_ep_queue(struct usb_ep *ep,
+				   struct usb_request *request,
+				   gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_request *priv_req;
+	int ret = 0;
+
+	request->actual = 0;
+	request->status = -EINPROGRESS;
+	priv_req = to_cdns3_request(request);
+	trace_cdns3_ep_queue(priv_req);
+
+	if (priv_dev->dev_ver < DEV_VER_V2) {
+		ret = cdns3_wa2_gadget_ep_queue(priv_dev, priv_ep,
+						priv_req);
+
+		if (ret == EINPROGRESS)
+			return 0;
+	}
+
+	ret = cdns3_prepare_aligned_request_buf(priv_req);
+	if (ret < 0)
+		return ret;
+
+	ret = usb_gadget_map_request(&priv_dev->gadget, request,
+				     usb_endpoint_dir_in(ep->desc));
+	if (ret)
+		return ret;
+
+	list_add_tail(&request->list, &priv_ep->deferred_req_list);
+
+	/*
+	 * If hardware endpoint configuration has not been set yet then
+	 * just queue request in deferred list. Transfer will be started in
+	 * cdns3_set_hw_configuration.
+	 */
+	if (priv_dev->hw_configured_flag && !(priv_ep->flags & EP_STALLED) &&
+	    !(priv_ep->flags & EP_STALL_PENDING))
+		cdns3_start_all_request(priv_dev, priv_ep);
+
+	return 0;
+}
+
+static int cdns3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
+				 gfp_t gfp_flags)
+{
+	struct usb_request *zlp_request;
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_device *priv_dev;
+	unsigned long flags;
+	int ret;
+
+	if (!request || !ep)
+		return -EINVAL;
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	ret = __cdns3_gadget_ep_queue(ep, request, gfp_flags);
+
+	if (ret == 0 && request->zero && request->length &&
+	    (request->length % ep->maxpacket == 0)) {
+		struct cdns3_request *priv_req;
+
+		zlp_request = cdns3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
+		zlp_request->buf = priv_dev->zlp_buf;
+		zlp_request->length = 0;
+
+		priv_req = to_cdns3_request(zlp_request);
+		priv_req->flags |= REQUEST_ZLP;
+
+		dev_dbg(priv_dev->dev, "Queuing ZLP for endpoint: %s\n",
+			priv_ep->name);
+		ret = __cdns3_gadget_ep_queue(ep, zlp_request, gfp_flags);
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_dequeue Remove request from transfer queue
+ * @ep: endpoint object associated with request
+ * @request: request object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+int cdns3_gadget_ep_dequeue(struct usb_ep *ep,
+			    struct usb_request *request)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct usb_request *req, *req_temp;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *link_trb;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!ep || !request || !ep->desc)
+		return -EINVAL;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	priv_req = to_cdns3_request(request);
+
+	trace_cdns3_ep_dequeue(priv_req);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	list_for_each_entry_safe(req, req_temp, &priv_ep->pending_req_list,
+				 list) {
+		if (request == req)
+			goto found;
+	}
+
+	list_for_each_entry_safe(req, req_temp, &priv_ep->deferred_req_list,
+				 list) {
+		if (request == req)
+			goto found;
+	}
+
+	goto not_found;
+
+found:
+
+	if (priv_ep->wa1_trb == priv_req->trb)
+		cdns3_wa1_restore_cycle_bit(priv_ep);
+
+	link_trb = priv_req->trb;
+	cdns3_move_deq_to_next_trb(priv_req);
+	cdns3_gadget_giveback(priv_ep, priv_req, -ECONNRESET);
+
+	/* Update ring */
+	request = cdns3_next_request(&priv_ep->deferred_req_list);
+	if (request) {
+		priv_req = to_cdns3_request(request);
+
+		link_trb->buffer = TRB_BUFFER(priv_ep->trb_pool_dma +
+					      (priv_req->start_trb * TRB_SIZE));
+		link_trb->control = (link_trb->control & TRB_CYCLE) |
+				    TRB_TYPE(TRB_LINK) | TRB_CHAIN | TRB_TOGGLE;
+	} else {
+		priv_ep->flags |= EP_UPDATE_EP_TRBADDR;
+	}
+
+not_found:
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+/**
+ * __cdns3_gadget_ep_set_halt Sets stall on selected endpoint
+ * Should be called after acquiring spin_lock and selecting ep
+ * @ep: endpoint object to set stall on.
+ */
+void __cdns3_gadget_ep_set_halt(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	trace_cdns3_halt(priv_ep, 1, 0);
+
+	if (!(priv_ep->flags & EP_STALLED)) {
+		u32 ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+
+		if (!(ep_sts_reg & EP_STS_DBUSY))
+			cdns3_ep_stall_flush(priv_ep);
+		else
+			priv_ep->flags |= EP_STALL_PENDING;
+	}
+}
+
+/**
+ * __cdns3_gadget_ep_clear_halt Clears stall on selected endpoint
+ * Should be called after acquiring spin_lock and selecting ep
+ * @ep: endpoint object to clear stall on
+ */
+int __cdns3_gadget_ep_clear_halt(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct usb_request *request;
+	int ret = 0;
+	int val;
+
+	trace_cdns3_halt(priv_ep, 0, 0);
+
+	writel(EP_CMD_CSTALL | EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	/* wait for EPRST cleared */
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+				  !(val & EP_CMD_EPRST), 100);
+	if (ret)
+		return -EINVAL;
+
+	priv_ep->flags &= ~(EP_STALLED | EP_STALL_PENDING);
+
+	request = cdns3_next_request(&priv_ep->pending_req_list);
+
+	if (request)
+		cdns3_rearm_transfer(priv_ep, 1);
+
+	cdns3_start_all_request(priv_dev, priv_ep);
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_set_halt Sets/clears stall on selected endpoint
+ * @ep: endpoint object to set/clear stall on
+ * @value: 1 for set stall, 0 for clear stall
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+int cdns3_gadget_ep_set_halt(struct usb_ep *ep, int value)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!(priv_ep->flags & EP_ENABLED))
+		return -EPERM;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	if (!value) {
+		priv_ep->flags &= ~EP_WEDGE;
+		ret = __cdns3_gadget_ep_clear_halt(priv_ep);
+	} else {
+		__cdns3_gadget_ep_set_halt(priv_ep);
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+extern const struct usb_ep_ops cdns3_gadget_ep0_ops;
+
+static const struct usb_ep_ops cdns3_gadget_ep_ops = {
+	.enable = cdns3_gadget_ep_enable,
+	.disable = cdns3_gadget_ep_disable,
+	.alloc_request = cdns3_gadget_ep_alloc_request,
+	.free_request = cdns3_gadget_ep_free_request,
+	.queue = cdns3_gadget_ep_queue,
+	.dequeue = cdns3_gadget_ep_dequeue,
+	.set_halt = cdns3_gadget_ep_set_halt,
+	.set_wedge = cdns3_gadget_ep_set_wedge,
+};
+
+/**
+ * cdns3_gadget_get_frame Returns number of actual ITP frame
+ * @gadget: gadget object
+ *
+ * Returns number of actual ITP frame
+ */
+static int cdns3_gadget_get_frame(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+
+	return readl(&priv_dev->regs->usb_itpn);
+}
+
+int __cdns3_gadget_wakeup(struct cdns3_device *priv_dev)
+{
+	enum usb_device_speed speed;
+
+	speed = cdns3_get_speed(priv_dev);
+
+	if (speed >= USB_SPEED_SUPER)
+		return 0;
+
+	/* Start driving resume signaling to indicate remote wakeup. */
+	writel(USB_CONF_LGO_L0, &priv_dev->regs->usb_conf);
+
+	return 0;
+}
+
+static int cdns3_gadget_wakeup(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	ret = __cdns3_gadget_wakeup(priv_dev);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+static int cdns3_gadget_set_selfpowered(struct usb_gadget *gadget,
+					int is_selfpowered)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_dev->is_selfpowered = !!is_selfpowered;
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return 0;
+}
+
+static int cdns3_gadget_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+
+	if (is_on)
+		writel(USB_CONF_DEVEN, &priv_dev->regs->usb_conf);
+	else
+		writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+
+	return 0;
+}
+
+static void cdns3_gadget_config(struct cdns3_device *priv_dev)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+	u32 reg;
+
+	cdns3_ep0_config(priv_dev);
+
+	/* enable interrupts for endpoint 0 (in and out) */
+	writel(EP_IEN_EP_OUT0 | EP_IEN_EP_IN0, &regs->ep_ien);
+
+	/*
+	 * Driver needs to modify LFPS minimal U1 Exit time for DEV_VER_TI_V1
+	 * revision of controller.
+	 */
+	if (priv_dev->dev_ver == DEV_VER_TI_V1) {
+		reg = readl(&regs->dbg_link1);
+
+		reg &= ~DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_MASK;
+		reg |= DBG_LINK1_LFPS_MIN_GEN_U1_EXIT(0x55) |
+		       DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_SET;
+		writel(reg, &regs->dbg_link1);
+	}
+
+	/*
+	 * By default some platforms has set protected access to memory.
+	 * This cause problem with cache, so driver restore non-secure
+	 * access to memory.
+	 */
+	reg = readl(&regs->dma_axi_ctrl);
+	reg |= DMA_AXI_CTRL_MARPROT(DMA_AXI_CTRL_NON_SECURE) |
+	       DMA_AXI_CTRL_MAWPROT(DMA_AXI_CTRL_NON_SECURE);
+	writel(reg, &regs->dma_axi_ctrl);
+
+	/* enable generic interrupt*/
+	writel(USB_IEN_INIT, &regs->usb_ien);
+	writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
+
+	cdns3_configure_dmult(priv_dev, NULL);
+
+	cdns3_gadget_pullup(&priv_dev->gadget, 1);
+}
+
+/**
+ * cdns3_gadget_udc_start Gadget start
+ * @gadget: gadget object
+ * @driver: driver which operates on this gadget
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_udc_start(struct usb_gadget *gadget,
+				  struct usb_gadget_driver *driver)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_dev->gadget_driver = driver;
+	cdns3_gadget_config(priv_dev);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return 0;
+}
+
+/**
+ * cdns3_gadget_udc_stop Stops gadget
+ * @gadget: gadget object
+ *
+ * Returns 0
+ */
+static int cdns3_gadget_udc_stop(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct cdns3_endpoint *priv_ep;
+	u32 bEndpointAddress;
+	struct usb_ep *ep;
+	int ret = 0;
+	int val;
+
+	priv_dev->gadget_driver = NULL;
+
+	priv_dev->onchip_used_size = 0;
+	priv_dev->out_mem_is_allocated = 0;
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		priv_ep = ep_to_cdns3_ep(ep);
+		bEndpointAddress = priv_ep->num | priv_ep->dir;
+		cdns3_select_ep(priv_dev, bEndpointAddress);
+		writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+		readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+					  !(val & EP_CMD_EPRST), 100);
+	}
+
+	/* disable interrupt for device */
+	writel(0, &priv_dev->regs->usb_ien);
+	writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+
+	return ret;
+}
+
+static const struct usb_gadget_ops cdns3_gadget_ops = {
+	.get_frame = cdns3_gadget_get_frame,
+	.wakeup = cdns3_gadget_wakeup,
+	.set_selfpowered = cdns3_gadget_set_selfpowered,
+	.pullup = cdns3_gadget_pullup,
+	.udc_start = cdns3_gadget_udc_start,
+	.udc_stop = cdns3_gadget_udc_stop,
+	.match_ep = cdns3_gadget_match_ep,
+};
+
+static void cdns3_free_all_eps(struct cdns3_device *priv_dev)
+{
+	int i;
+
+	/* ep0 OUT point to ep0 IN. */
+	priv_dev->eps[16] = NULL;
+
+	for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++)
+		if (priv_dev->eps[i]) {
+			cdns3_free_trb_pool(priv_dev->eps[i]);
+			devm_kfree(priv_dev->dev, priv_dev->eps[i]);
+		}
+}
+
+/**
+ * cdns3_init_eps Initializes software endpoints of gadget
+ * @cdns3: extended gadget object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_init_eps(struct cdns3_device *priv_dev)
+{
+	u32 ep_enabled_reg, iso_ep_reg;
+	struct cdns3_endpoint *priv_ep;
+	int ep_dir, ep_number;
+	u32 ep_mask;
+	int ret = 0;
+	int i;
+
+	/* Read it from USB_CAP3 to USB_CAP5 */
+	ep_enabled_reg = readl(&priv_dev->regs->usb_cap3);
+	iso_ep_reg = readl(&priv_dev->regs->usb_cap4);
+
+	dev_dbg(priv_dev->dev, "Initializing non-zero endpoints\n");
+
+	for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++) {
+		ep_dir = i >> 4;	/* i div 16 */
+		ep_number = i & 0xF;	/* i % 16 */
+		ep_mask = BIT(i);
+
+		if (!(ep_enabled_reg & ep_mask))
+			continue;
+
+		if (ep_dir && !ep_number) {
+			priv_dev->eps[i] = priv_dev->eps[0];
+			continue;
+		}
+
+		priv_ep = devm_kzalloc(priv_dev->dev, sizeof(*priv_ep),
+				       GFP_KERNEL);
+		if (!priv_ep) {
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		/* set parent of endpoint object */
+		priv_ep->cdns3_dev = priv_dev;
+		priv_dev->eps[i] = priv_ep;
+		priv_ep->num = ep_number;
+		priv_ep->dir = ep_dir ? USB_DIR_IN : USB_DIR_OUT;
+
+		if (!ep_number) {
+			ret = cdns3_init_ep0(priv_dev, priv_ep);
+			if (ret) {
+				dev_err(priv_dev->dev, "Failed to init ep0\n");
+				goto err;
+			}
+		} else {
+			snprintf(priv_ep->name, sizeof(priv_ep->name), "ep%d%s",
+				 ep_number, !!ep_dir ? "in" : "out");
+			priv_ep->endpoint.name = priv_ep->name;
+
+			usb_ep_set_maxpacket_limit(&priv_ep->endpoint,
+						   CDNS3_EP_MAX_PACKET_LIMIT);
+			priv_ep->endpoint.max_streams = CDNS3_EP_MAX_STREAMS;
+			priv_ep->endpoint.ops = &cdns3_gadget_ep_ops;
+			if (ep_dir)
+				priv_ep->endpoint.caps.dir_in = 1;
+			else
+				priv_ep->endpoint.caps.dir_out = 1;
+
+			if (iso_ep_reg & ep_mask)
+				priv_ep->endpoint.caps.type_iso = 1;
+
+			priv_ep->endpoint.caps.type_bulk = 1;
+			priv_ep->endpoint.caps.type_int = 1;
+
+			list_add_tail(&priv_ep->endpoint.ep_list,
+				      &priv_dev->gadget.ep_list);
+		}
+
+		priv_ep->flags = 0;
+
+		dev_info(priv_dev->dev, "Initialized  %s support: %s %s\n",
+			 priv_ep->name,
+			 priv_ep->endpoint.caps.type_bulk ? "BULK, INT" : "",
+			 priv_ep->endpoint.caps.type_iso ? "ISO" : "");
+
+		INIT_LIST_HEAD(&priv_ep->pending_req_list);
+		INIT_LIST_HEAD(&priv_ep->deferred_req_list);
+		INIT_LIST_HEAD(&priv_ep->wa2_descmiss_req_list);
+	}
+
+	return 0;
+err:
+	cdns3_free_all_eps(priv_dev);
+	return -ENOMEM;
+}
+
+void cdns3_gadget_exit(struct cdns3 *cdns)
+{
+	struct cdns3_device *priv_dev;
+
+	priv_dev = cdns->gadget_dev;
+
+	usb_del_gadget_udc(&priv_dev->gadget);
+
+	cdns3_free_all_eps(priv_dev);
+
+	while (!list_empty(&priv_dev->aligned_buf_list)) {
+		struct cdns3_aligned_buf *buf;
+
+		buf = cdns3_next_align_buf(&priv_dev->aligned_buf_list);
+		dma_free_coherent(buf->buf);
+
+		list_del(&buf->list);
+		kfree(buf);
+	}
+
+	dma_free_coherent(priv_dev->setup_buf);
+
+	kfree(priv_dev->zlp_buf);
+	kfree(priv_dev);
+	cdns->gadget_dev = NULL;
+	cdns3_drd_switch_gadget(cdns, 0);
+}
+
+static int cdns3_gadget_start(struct cdns3 *cdns)
+{
+	struct cdns3_device *priv_dev;
+	u32 max_speed;
+	int ret;
+
+	priv_dev = kzalloc(sizeof(*priv_dev), GFP_KERNEL);
+	if (!priv_dev)
+		return -ENOMEM;
+
+	cdns->gadget_dev = priv_dev;
+	priv_dev->sysdev = cdns->dev;
+	priv_dev->dev = cdns->dev;
+	priv_dev->regs = cdns->dev_regs;
+
+	dev_read_u32(priv_dev->dev, "cdns,on-chip-buff-size",
+		     &priv_dev->onchip_buffers);
+
+	if (priv_dev->onchip_buffers <=  0) {
+		u32 reg = readl(&priv_dev->regs->usb_cap2);
+
+		priv_dev->onchip_buffers = USB_CAP2_ACTUAL_MEM_SIZE(reg);
+	}
+
+	if (!priv_dev->onchip_buffers)
+		priv_dev->onchip_buffers = 256;
+
+	max_speed = usb_get_maximum_speed(dev_of_offset(cdns->dev));
+
+	/* Check the maximum_speed parameter */
+	switch (max_speed) {
+	case USB_SPEED_FULL:
+		writel(USB_CONF_SFORCE_FS, &priv_dev->regs->usb_conf);
+		break;
+	case USB_SPEED_HIGH:
+		writel(USB_CONF_USB3DIS, &priv_dev->regs->usb_conf);
+		break;
+	case USB_SPEED_SUPER:
+		break;
+	default:
+		dev_err(cdns->dev, "invalid maximum_speed parameter %d\n",
+			max_speed);
+		/* fall through */
+	case USB_SPEED_UNKNOWN:
+		/* default to superspeed */
+		max_speed = USB_SPEED_SUPER;
+		break;
+	}
+
+	/* fill gadget fields */
+	priv_dev->gadget.max_speed = max_speed;
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+	priv_dev->gadget.ops = &cdns3_gadget_ops;
+	priv_dev->gadget.name = "cdns3-gadget";
+#ifndef __UBOOT__
+	priv_dev->gadget.name = "usb-ss-gadget";
+	priv_dev->gadget.sg_supported = 1;
+	priv_dev->gadget.quirk_avoids_skb_reserve = 1;
+#endif
+
+	spin_lock_init(&priv_dev->lock);
+	INIT_WORK(&priv_dev->pending_status_wq,
+		  cdns3_pending_setup_status_handler);
+
+	/* initialize endpoint container */
+	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
+	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);
+
+	ret = cdns3_init_eps(priv_dev);
+	if (ret) {
+		dev_err(priv_dev->dev, "Failed to create endpoints\n");
+		goto err1;
+	}
+
+	/* allocate memory for setup packet buffer */
+	priv_dev->setup_buf =
+		dma_alloc_coherent(8, (unsigned long *)&priv_dev->setup_dma);
+	if (!priv_dev->setup_buf) {
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	priv_dev->dev_ver = readl(&priv_dev->regs->usb_cap6);
+
+	dev_dbg(priv_dev->dev, "Device Controller version: %08x\n",
+		readl(&priv_dev->regs->usb_cap6));
+	dev_dbg(priv_dev->dev, "USB Capabilities:: %08x\n",
+		readl(&priv_dev->regs->usb_cap1));
+	dev_dbg(priv_dev->dev, "On-Chip memory cnfiguration: %08x\n",
+		readl(&priv_dev->regs->usb_cap2));
+
+	priv_dev->dev_ver = GET_DEV_BASE_VERSION(priv_dev->dev_ver);
+
+	priv_dev->zlp_buf = kzalloc(CDNS3_EP_ZLP_BUF_SIZE, GFP_KERNEL);
+	if (!priv_dev->zlp_buf) {
+		ret = -ENOMEM;
+		goto err3;
+	}
+
+	/* add USB gadget device */
+	ret = usb_add_gadget_udc((struct device *)priv_dev->dev,
+				 &priv_dev->gadget);
+	if (ret < 0) {
+		dev_err(priv_dev->dev,
+			"Failed to register USB device controller\n");
+		goto err4;
+	}
+
+	return 0;
+err4:
+	kfree(priv_dev->zlp_buf);
+err3:
+	dma_free_coherent(priv_dev->setup_buf);
+err2:
+	cdns3_free_all_eps(priv_dev);
+err1:
+	cdns->gadget_dev = NULL;
+	return ret;
+}
+
+static int __cdns3_gadget_init(struct cdns3 *cdns)
+{
+	int ret = 0;
+
+	cdns3_drd_switch_gadget(cdns, 1);
+
+	ret = cdns3_gadget_start(cdns);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup)
+{
+	struct cdns3_device *priv_dev = cdns->gadget_dev;
+
+	cdns3_disconnect_gadget(priv_dev);
+
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+	usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
+	cdns3_hw_reset_eps_config(priv_dev);
+
+	/* disable interrupt for device */
+	writel(0, &priv_dev->regs->usb_ien);
+
+	cdns3_gadget_pullup(&priv_dev->gadget, 0);
+
+	return 0;
+}
+
+static int cdns3_gadget_resume(struct cdns3 *cdns, bool hibernated)
+{
+	struct cdns3_device *priv_dev = cdns->gadget_dev;
+
+	if (!priv_dev->gadget_driver)
+		return 0;
+
+	cdns3_gadget_config(priv_dev);
+
+	return 0;
+}
+
+/**
+ * cdns3_gadget_init - initialize device structure
+ *
+ * cdns: cdns3 instance
+ *
+ * This function initializes the gadget.
+ */
+int cdns3_gadget_init(struct cdns3 *cdns)
+{
+	struct cdns3_role_driver *rdrv;
+
+	rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
+	if (!rdrv)
+		return -ENOMEM;
+
+	rdrv->start	= __cdns3_gadget_init;
+	rdrv->stop	= cdns3_gadget_exit;
+	rdrv->suspend	= cdns3_gadget_suspend;
+	rdrv->resume	= cdns3_gadget_resume;
+	rdrv->state	= CDNS3_ROLE_STATE_INACTIVE;
+	rdrv->name	= "gadget";
+	cdns->roles[USB_ROLE_DEVICE] = rdrv;
+
+	return 0;
+}
+
+/**
+ * cdns3_gadget_uboot_handle_interrupt - handle cdns3 gadget interrupt
+ * @cdns: pointer to struct cdns3
+ *
+ * Handles ep0 and gadget interrupt
+ */
+static void cdns3_gadget_uboot_handle_interrupt(struct cdns3 *cdns)
+{
+	int ret = cdns3_device_irq_handler(0, cdns);
+
+	if (ret == IRQ_WAKE_THREAD)
+		cdns3_device_thread_irq_handler(0, cdns);
+}
+
+int dm_usb_gadget_handle_interrupts(struct udevice *dev)
+{
+	struct cdns3 *cdns = dev_get_priv(dev);
+
+	cdns3_gadget_uboot_handle_interrupt(cdns);
+
+	return 0;
+}
diff --git a/drivers/usb/cdns3/gadget.h b/drivers/usb/cdns3/gadget.h
new file mode 100644
index 0000000..3d5242b
--- /dev/null
+++ b/drivers/usb/cdns3/gadget.h
@@ -0,0 +1,1338 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * USBSS device controller driver header file
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *         Pawel Jez <pjez@cadence.com>
+ *         Peter Chen <peter.chen@nxp.com>
+ */
+#ifndef __LINUX_CDNS3_GADGET
+#define __LINUX_CDNS3_GADGET
+#include <linux/usb/gadget.h>
+
+/*
+ * USBSS-DEV register interface.
+ * This corresponds to the USBSS Device Controller Interface
+ */
+
+/**
+ * struct cdns3_usb_regs - device controller registers.
+ * @usb_conf:      Global Configuration.
+ * @usb_sts:       Global Status.
+ * @usb_cmd:       Global Command.
+ * @usb_itpn:      ITP/SOF number.
+ * @usb_lpm:       Global Command.
+ * @usb_ien:       USB Interrupt Enable.
+ * @usb_ists:      USB Interrupt Status.
+ * @ep_sel:        Endpoint Select.
+ * @ep_traddr:     Endpoint Transfer Ring Address.
+ * @ep_cfg:        Endpoint Configuration.
+ * @ep_cmd:        Endpoint Command.
+ * @ep_sts:        Endpoint Status.
+ * @ep_sts_sid:    Endpoint Status.
+ * @ep_sts_en:     Endpoint Status Enable.
+ * @drbl:          Doorbell.
+ * @ep_ien:        EP Interrupt Enable.
+ * @ep_ists:       EP Interrupt Status.
+ * @usb_pwr:       Global Power Configuration.
+ * @usb_conf2:     Global Configuration 2.
+ * @usb_cap1:      Capability 1.
+ * @usb_cap2:      Capability 2.
+ * @usb_cap3:      Capability 3.
+ * @usb_cap4:      Capability 4.
+ * @usb_cap5:      Capability 5.
+ * @usb_cap6:      Capability 6.
+ * @usb_cpkt1:     Custom Packet 1.
+ * @usb_cpkt2:     Custom Packet 2.
+ * @usb_cpkt3:     Custom Packet 3.
+ * @ep_dma_ext_addr: Upper address for DMA operations.
+ * @buf_addr:      Address for On-chip Buffer operations.
+ * @buf_data:      Data for On-chip Buffer operations.
+ * @buf_ctrl:      On-chip Buffer Access Control.
+ * @dtrans:        DMA Transfer Mode.
+ * @tdl_from_trb:  Source of TD Configuration.
+ * @tdl_beh:       TDL Behavior Configuration.
+ * @ep_tdl:        Endpoint TDL.
+ * @tdl_beh2:      TDL Behavior 2 Configuration.
+ * @dma_adv_td:    DMA Advance TD Configuration.
+ * @reserved1:     Reserved.
+ * @cfg_regs:      Configuration.
+ * @reserved2:     Reserved.
+ * @dma_axi_ctrl:  AXI Control.
+ * @dma_axi_id:    AXI ID register.
+ * @dma_axi_cap:   AXI Capability.
+ * @dma_axi_ctrl0: AXI Control 0.
+ * @dma_axi_ctrl1: AXI Control 1.
+ */
+struct cdns3_usb_regs {
+	__le32 usb_conf;
+	__le32 usb_sts;
+	__le32 usb_cmd;
+	__le32 usb_itpn;
+	__le32 usb_lpm;
+	__le32 usb_ien;
+	__le32 usb_ists;
+	__le32 ep_sel;
+	__le32 ep_traddr;
+	__le32 ep_cfg;
+	__le32 ep_cmd;
+	__le32 ep_sts;
+	__le32 ep_sts_sid;
+	__le32 ep_sts_en;
+	__le32 drbl;
+	__le32 ep_ien;
+	__le32 ep_ists;
+	__le32 usb_pwr;
+	__le32 usb_conf2;
+	__le32 usb_cap1;
+	__le32 usb_cap2;
+	__le32 usb_cap3;
+	__le32 usb_cap4;
+	__le32 usb_cap5;
+	__le32 usb_cap6;
+	__le32 usb_cpkt1;
+	__le32 usb_cpkt2;
+	__le32 usb_cpkt3;
+	__le32 ep_dma_ext_addr;
+	__le32 buf_addr;
+	__le32 buf_data;
+	__le32 buf_ctrl;
+	__le32 dtrans;
+	__le32 tdl_from_trb;
+	__le32 tdl_beh;
+	__le32 ep_tdl;
+	__le32 tdl_beh2;
+	__le32 dma_adv_td;
+	__le32 reserved1[26];
+	__le32 cfg_reg1;
+	__le32 dbg_link1;
+	__le32 dbg_link2;
+	__le32 cfg_regs[74];
+	__le32 reserved2[51];
+	__le32 dma_axi_ctrl;
+	__le32 dma_axi_id;
+	__le32 dma_axi_cap;
+	__le32 dma_axi_ctrl0;
+	__le32 dma_axi_ctrl1;
+};
+
+/* USB_CONF - bitmasks */
+/* Reset USB device configuration. */
+#define USB_CONF_CFGRST		BIT(0)
+/* Set Configuration. */
+#define USB_CONF_CFGSET		BIT(1)
+/* Disconnect USB device in SuperSpeed. */
+#define USB_CONF_USB3DIS	BIT(3)
+/* Disconnect USB device in HS/FS */
+#define USB_CONF_USB2DIS	BIT(4)
+/* Little Endian access - default */
+#define USB_CONF_LENDIAN	BIT(5)
+/*
+ * Big Endian access. Driver assume that byte order for
+ * SFRs access always is as Little Endian so this bit
+ * is not used.
+ */
+#define USB_CONF_BENDIAN	BIT(6)
+/* Device software reset. */
+#define USB_CONF_SWRST		BIT(7)
+/* Singular DMA transfer mode. Only for VER < DEV_VER_V3*/
+#define USB_CONF_DSING		BIT(8)
+/* Multiple DMA transfers mode. Only for VER < DEV_VER_V3 */
+#define USB_CONF_DMULT		BIT(9)
+/* DMA clock turn-off enable. */
+#define USB_CONF_DMAOFFEN	BIT(10)
+/* DMA clock turn-off disable. */
+#define USB_CONF_DMAOFFDS	BIT(11)
+/* Clear Force Full Speed. */
+#define USB_CONF_CFORCE_FS	BIT(12)
+/* Set Force Full Speed. */
+#define USB_CONF_SFORCE_FS	BIT(13)
+/* Device enable. */
+#define USB_CONF_DEVEN		BIT(14)
+/* Device disable. */
+#define USB_CONF_DEVDS		BIT(15)
+/* L1 LPM state entry enable (used in HS/FS mode). */
+#define USB_CONF_L1EN		BIT(16)
+/* L1 LPM state entry disable (used in HS/FS mode). */
+#define USB_CONF_L1DS		BIT(17)
+/* USB 2.0 clock gate disable. */
+#define USB_CONF_CLK2OFFEN	BIT(18)
+/* USB 2.0 clock gate enable. */
+#define USB_CONF_CLK2OFFDS	BIT(19)
+/* L0 LPM state entry request (used in HS/FS mode). */
+#define USB_CONF_LGO_L0		BIT(20)
+/* USB 3.0 clock gate disable. */
+#define USB_CONF_CLK3OFFEN	BIT(21)
+/* USB 3.0 clock gate enable. */
+#define USB_CONF_CLK3OFFDS	BIT(22)
+/* Bit 23 is reserved*/
+/* U1 state entry enable (used in SS mode). */
+#define USB_CONF_U1EN		BIT(24)
+/* U1 state entry disable (used in SS mode). */
+#define USB_CONF_U1DS		BIT(25)
+/* U2 state entry enable (used in SS mode). */
+#define USB_CONF_U2EN		BIT(26)
+/* U2 state entry disable (used in SS mode). */
+#define USB_CONF_U2DS		BIT(27)
+/* U0 state entry request (used in SS mode). */
+#define USB_CONF_LGO_U0		BIT(28)
+/* U1 state entry request (used in SS mode). */
+#define USB_CONF_LGO_U1		BIT(29)
+/* U2 state entry request (used in SS mode). */
+#define USB_CONF_LGO_U2		BIT(30)
+/* SS.Inactive state entry request (used in SS mode) */
+#define USB_CONF_LGO_SSINACT	BIT(31)
+
+/* USB_STS - bitmasks */
+/*
+ * Configuration status.
+ * 1 - device is in the configured state.
+ * 0 - device is not configured.
+ */
+#define USB_STS_CFGSTS_MASK	BIT(0)
+#define USB_STS_CFGSTS(p)	((p) & USB_STS_CFGSTS_MASK)
+/*
+ * On-chip memory overflow.
+ * 0 - On-chip memory status OK.
+ * 1 - On-chip memory overflow.
+ */
+#define USB_STS_OV_MASK		BIT(1)
+#define USB_STS_OV(p)		((p) & USB_STS_OV_MASK)
+/*
+ * SuperSpeed connection status.
+ * 0 - USB in SuperSpeed mode disconnected.
+ * 1 - USB in SuperSpeed mode connected.
+ */
+#define USB_STS_USB3CONS_MASK	BIT(2)
+#define USB_STS_USB3CONS(p)	((p) & USB_STS_USB3CONS_MASK)
+/*
+ * DMA transfer configuration status.
+ * 0 - single request.
+ * 1 - multiple TRB chain
+ * Supported only for controller version <  DEV_VER_V3
+ */
+#define USB_STS_DTRANS_MASK	BIT(3)
+#define USB_STS_DTRANS(p)	((p) & USB_STS_DTRANS_MASK)
+/*
+ * Device speed.
+ * 0 - Undefined (value after reset).
+ * 1 - Low speed
+ * 2 - Full speed
+ * 3 - High speed
+ * 4 - Super speed
+ */
+#define USB_STS_USBSPEED_MASK	GENMASK(6, 4)
+#define USB_STS_USBSPEED(p)	(((p) & USB_STS_USBSPEED_MASK) >> 4)
+#define USB_STS_LS		(0x1 << 4)
+#define USB_STS_FS		(0x2 << 4)
+#define USB_STS_HS		(0x3 << 4)
+#define USB_STS_SS		(0x4 << 4)
+#define DEV_UNDEFSPEED(p)	(((p) & USB_STS_USBSPEED_MASK) == (0x0 << 4))
+#define DEV_LOWSPEED(p)		(((p) & USB_STS_USBSPEED_MASK) == USB_STS_LS)
+#define DEV_FULLSPEED(p)	(((p) & USB_STS_USBSPEED_MASK) == USB_STS_FS)
+#define DEV_HIGHSPEED(p)	(((p) & USB_STS_USBSPEED_MASK) == USB_STS_HS)
+#define DEV_SUPERSPEED(p)	(((p) & USB_STS_USBSPEED_MASK) == USB_STS_SS)
+/*
+ * Endianness for SFR access.
+ * 0 - Little Endian order (default after hardware reset).
+ * 1 - Big Endian order
+ */
+#define USB_STS_ENDIAN_MASK	BIT(7)
+#define USB_STS_ENDIAN(p)	((p) & USB_STS_ENDIAN_MASK)
+/*
+ * HS/FS clock turn-off status.
+ * 0 - hsfs clock is always on.
+ * 1 - hsfs clock turn-off in L2 (HS/FS mode) is enabled
+ *          (default after hardware reset).
+ */
+#define USB_STS_CLK2OFF_MASK	BIT(8)
+#define USB_STS_CLK2OFF(p)	((p) & USB_STS_CLK2OFF_MASK)
+/*
+ * PCLK clock turn-off status.
+ * 0 - pclk clock is always on.
+ * 1 - pclk clock turn-off in U3 (SS mode) is enabled
+ *          (default after hardware reset).
+ */
+#define USB_STS_CLK3OFF_MASK	BIT(9)
+#define USB_STS_CLK3OFF(p)	((p) & USB_STS_CLK3OFF_MASK)
+/*
+ * Controller in reset state.
+ * 0 - Internal reset is active.
+ * 1 - Internal reset is not active and controller is fully operational.
+ */
+#define USB_STS_IN_RST_MASK	BIT(10)
+#define USB_STS_IN_RST(p)	((p) & USB_STS_IN_RST_MASK)
+/*
+ * Status of the "TDL calculation basing on TRB" feature.
+ * 0 - disabled
+ * 1 - enabled
+ * Supported only for DEV_VER_V2 controller version.
+ */
+#define USB_STS_TDL_TRB_ENABLED	BIT(11)
+/*
+ * Device enable Status.
+ * 0 - USB device is disabled (VBUS input is disconnected from internal logic).
+ * 1 - USB device is enabled (VBUS input is connected to the internal logic).
+ */
+#define USB_STS_DEVS_MASK	BIT(14)
+#define USB_STS_DEVS(p)		((p) & USB_STS_DEVS_MASK)
+/*
+ * Address status.
+ * 0 - USB device is default state.
+ * 1 - USB device is at least in address state.
+ */
+#define USB_STS_ADDRESSED_MASK	BIT(15)
+#define USB_STS_ADDRESSED(p)	((p) & USB_STS_ADDRESSED_MASK)
+/*
+ * L1 LPM state enable status (used in HS/FS mode).
+ * 0 - Entering to L1 LPM state disabled.
+ * 1 - Entering to L1 LPM state enabled.
+ */
+#define USB_STS_L1ENS_MASK	BIT(16)
+#define USB_STS_L1ENS(p)	((p) & USB_STS_L1ENS_MASK)
+/*
+ * Internal VBUS connection status (used both in HS/FS  and SS mode).
+ * 0 - internal VBUS is not detected.
+ * 1 - internal VBUS is detected.
+ */
+#define USB_STS_VBUSS_MASK	BIT(17)
+#define USB_STS_VBUSS(p)	((p) & USB_STS_VBUSS_MASK)
+/*
+ * HS/FS LPM  state (used in FS/HS mode).
+ * 0 - L0 State
+ * 1 - L1 State
+ * 2 - L2 State
+ * 3 - L3 State
+ */
+#define USB_STS_LPMST_MASK	GENMASK(19, 18)
+#define DEV_L0_STATE(p)		(((p) & USB_STS_LPMST_MASK) == (0x0 << 18))
+#define DEV_L1_STATE(p)		(((p) & USB_STS_LPMST_MASK) == (0x1 << 18))
+#define DEV_L2_STATE(p)		(((p) & USB_STS_LPMST_MASK) == (0x2 << 18))
+#define DEV_L3_STATE(p)		(((p) & USB_STS_LPMST_MASK) == (0x3 << 18))
+/*
+ * Disable HS status (used in FS/HS mode).
+ * 0 - the disconnect bit for HS/FS mode is set .
+ * 1 - the disconnect bit for HS/FS mode is not set.
+ */
+#define USB_STS_USB2CONS_MASK	BIT(20)
+#define USB_STS_USB2CONS(p)	((p) & USB_STS_USB2CONS_MASK)
+/*
+ * HS/FS mode connection status (used in FS/HS mode).
+ * 0 - High Speed operations in USB2.0 (FS/HS) mode not disabled.
+ * 1 - High Speed operations in USB2.0 (FS/HS).
+ */
+#define USB_STS_DISABLE_HS_MASK	BIT(21)
+#define USB_STS_DISABLE_HS(p)	((p) & USB_STS_DISABLE_HS_MASK)
+/*
+ * U1 state enable status (used in SS mode).
+ * 0 - Entering to  U1 state disabled.
+ * 1 - Entering to  U1 state enabled.
+ */
+#define USB_STS_U1ENS_MASK	BIT(24)
+#define USB_STS_U1ENS(p)	((p) & USB_STS_U1ENS_MASK)
+/*
+ * U2 state enable status (used in SS mode).
+ * 0 - Entering to  U2 state disabled.
+ * 1 - Entering to  U2 state enabled.
+ */
+#define USB_STS_U2ENS_MASK	BIT(25)
+#define USB_STS_U2ENS(p)	((p) & USB_STS_U2ENS_MASK)
+/*
+ * SuperSpeed Link LTSSM state. This field reflects USBSS-DEV current
+ * SuperSpeed link state
+ */
+#define USB_STS_LST_MASK	GENMASK(29, 26)
+#define DEV_LST_U0		(((p) & USB_STS_LST_MASK) == (0x0 << 26))
+#define DEV_LST_U1		(((p) & USB_STS_LST_MASK) == (0x1 << 26))
+#define DEV_LST_U2		(((p) & USB_STS_LST_MASK) == (0x2 << 26))
+#define DEV_LST_U3		(((p) & USB_STS_LST_MASK) == (0x3 << 26))
+#define DEV_LST_DISABLED	(((p) & USB_STS_LST_MASK) == (0x4 << 26))
+#define DEV_LST_RXDETECT	(((p) & USB_STS_LST_MASK) == (0x5 << 26))
+#define DEV_LST_INACTIVE	(((p) & USB_STS_LST_MASK) == (0x6 << 26))
+#define DEV_LST_POLLING		(((p) & USB_STS_LST_MASK) == (0x7 << 26))
+#define DEV_LST_RECOVERY	(((p) & USB_STS_LST_MASK) == (0x8 << 26))
+#define DEV_LST_HOT_RESET	(((p) & USB_STS_LST_MASK) == (0x9 << 26))
+#define DEV_LST_COMP_MODE	(((p) & USB_STS_LST_MASK) == (0xa << 26))
+#define DEV_LST_LB_STATE	(((p) & USB_STS_LST_MASK) == (0xb << 26))
+/*
+ * DMA clock turn-off status.
+ * 0 - DMA clock is always on (default after hardware reset).
+ * 1 - DMA clock turn-off in U1, U2 and U3 (SS mode) is enabled.
+ */
+#define USB_STS_DMAOFF_MASK	BIT(30)
+#define USB_STS_DMAOFF(p)	((p) & USB_STS_DMAOFF_MASK)
+/*
+ * SFR Endian status.
+ * 0 - Little Endian order (default after hardware reset).
+ * 1 - Big Endian order.
+ */
+#define USB_STS_ENDIAN2_MASK	BIT(31)
+#define USB_STS_ENDIAN2(p)	((p) & USB_STS_ENDIAN2_MASK)
+
+/* USB_CMD -  bitmasks */
+/* Set Function Address */
+#define USB_CMD_SET_ADDR	BIT(0)
+/*
+ * Function Address This field is saved to the device only when the field
+ * SET_ADDR is set '1 ' during write to USB_CMD register.
+ * Software is responsible for entering the address of the device during
+ * SET_ADDRESS request service. This field should be set immediately after
+ * the SETUP packet is decoded, and prior to confirmation of the status phase
+ */
+#define USB_CMD_FADDR_MASK	GENMASK(7, 1)
+#define USB_CMD_FADDR(p)	(((p) << 1) & USB_CMD_FADDR_MASK)
+/* Send Function Wake Device Notification TP (used only in SS mode). */
+#define USB_CMD_SDNFW		BIT(8)
+/* Set Test Mode (used only in HS/FS mode). */
+#define USB_CMD_STMODE		BIT(9)
+/* Test mode selector (used only in HS/FS mode) */
+#define USB_STS_TMODE_SEL_MASK	GENMASK(11, 10)
+#define USB_STS_TMODE_SEL(p)	(((p) << 10) & USB_STS_TMODE_SEL_MASK)
+/*
+ *  Send Latency Tolerance Message Device Notification TP (used only
+ *  in SS mode).
+ */
+#define USB_CMD_SDNLTM		BIT(12)
+/* Send Custom Transaction Packet (used only in SS mode) */
+#define USB_CMD_SPKT		BIT(13)
+/*Device Notification 'Function Wake' - Interface value (only in SS mode. */
+#define USB_CMD_DNFW_INT_MASK	GENMASK(23, 16)
+#define USB_STS_DNFW_INT(p)	(((p) << 16) & USB_CMD_DNFW_INT_MASK)
+/*
+ * Device Notification 'Latency Tolerance Message' -373 BELT value [7:0]
+ * (used only in SS mode).
+ */
+#define USB_CMD_DNLTM_BELT_MASK	GENMASK(27, 16)
+#define USB_STS_DNLTM_BELT(p)	(((p) << 16) & USB_CMD_DNLTM_BELT_MASK)
+
+/* USB_ITPN - bitmasks */
+/*
+ * ITP(SS) / SOF (HS/FS) number
+ * In SS mode this field represent number of last ITP received from host.
+ * In HS/FS mode this field represent number of last SOF received from host.
+ */
+#define USB_ITPN_MASK		GENMASK(13, 0)
+#define USB_ITPN(p)		((p) & USB_ITPN_MASK)
+
+/* USB_LPM - bitmasks */
+/* Host Initiated Resume Duration. */
+#define USB_LPM_HIRD_MASK	GENMASK(3, 0)
+#define USB_LPM_HIRD(p)		((p) & USB_LPM_HIRD_MASK)
+/* Remote Wakeup Enable (bRemoteWake). */
+#define USB_LPM_BRW		BIT(4)
+
+/* USB_IEN - bitmasks */
+/* SS connection interrupt enable */
+#define USB_IEN_CONIEN		BIT(0)
+/* SS disconnection interrupt enable. */
+#define USB_IEN_DISIEN		BIT(1)
+/* USB SS warm reset interrupt enable. */
+#define USB_IEN_UWRESIEN	BIT(2)
+/* USB SS hot reset interrupt enable */
+#define USB_IEN_UHRESIEN	BIT(3)
+/* SS link U3 state enter interrupt enable (suspend).*/
+#define USB_IEN_U3ENTIEN	BIT(4)
+/* SS link U3 state exit interrupt enable (wakeup). */
+#define USB_IEN_U3EXTIEN	BIT(5)
+/* SS link U2 state enter interrupt enable.*/
+#define USB_IEN_U2ENTIEN	BIT(6)
+/* SS link U2 state exit interrupt enable.*/
+#define USB_IEN_U2EXTIEN	BIT(7)
+/* SS link U1 state enter interrupt enable.*/
+#define USB_IEN_U1ENTIEN	BIT(8)
+/* SS link U1 state exit interrupt enable.*/
+#define USB_IEN_U1EXTIEN	BIT(9)
+/* ITP/SOF packet detected interrupt enable.*/
+#define USB_IEN_ITPIEN		BIT(10)
+/* Wakeup interrupt enable.*/
+#define USB_IEN_WAKEIEN		BIT(11)
+/* Send Custom Packet interrupt enable.*/
+#define USB_IEN_SPKTIEN		BIT(12)
+/* HS/FS mode connection interrupt enable.*/
+#define USB_IEN_CON2IEN		BIT(16)
+/* HS/FS mode disconnection interrupt enable.*/
+#define USB_IEN_DIS2IEN		BIT(17)
+/* USB reset (HS/FS mode) interrupt enable.*/
+#define USB_IEN_U2RESIEN	BIT(18)
+/* LPM L2 state enter interrupt enable.*/
+#define USB_IEN_L2ENTIEN	BIT(20)
+/* LPM  L2 state exit interrupt enable.*/
+#define USB_IEN_L2EXTIEN	BIT(21)
+/* LPM L1 state enter interrupt enable.*/
+#define USB_IEN_L1ENTIEN	BIT(24)
+/* LPM  L1 state exit interrupt enable.*/
+#define USB_IEN_L1EXTIEN	BIT(25)
+/* Configuration reset interrupt enable.*/
+#define USB_IEN_CFGRESIEN	BIT(26)
+/* Start of the USB SS warm reset interrupt enable.*/
+#define USB_IEN_UWRESSIEN	BIT(28)
+/* End of the USB SS warm reset interrupt enable.*/
+#define USB_IEN_UWRESEIEN	BIT(29)
+
+#define USB_IEN_INIT  (USB_IEN_U2RESIEN | USB_ISTS_DIS2I | USB_IEN_CON2IEN \
+		       | USB_IEN_UHRESIEN | USB_IEN_UWRESIEN | USB_IEN_DISIEN \
+		       | USB_IEN_CONIEN | USB_IEN_U3EXTIEN | USB_IEN_L2ENTIEN \
+		       | USB_IEN_L2EXTIEN | USB_IEN_L1ENTIEN | USB_IEN_U3ENTIEN)
+
+/* USB_ISTS - bitmasks */
+/* SS Connection detected. */
+#define USB_ISTS_CONI		BIT(0)
+/* SS Disconnection detected. */
+#define USB_ISTS_DISI		BIT(1)
+/* UUSB warm reset detectede. */
+#define USB_ISTS_UWRESI		BIT(2)
+/* USB hot reset detected. */
+#define USB_ISTS_UHRESI		BIT(3)
+/* U3 link state enter detected (suspend).*/
+#define USB_ISTS_U3ENTI		BIT(4)
+/* U3 link state exit detected (wakeup). */
+#define USB_ISTS_U3EXTI		BIT(5)
+/* U2 link state enter detected.*/
+#define USB_ISTS_U2ENTI		BIT(6)
+/* U2 link state exit detected.*/
+#define USB_ISTS_U2EXTI		BIT(7)
+/* U1 link state enter detected.*/
+#define USB_ISTS_U1ENTI		BIT(8)
+/* U1 link state exit detected.*/
+#define USB_ISTS_U1EXTI		BIT(9)
+/* ITP/SOF packet detected.*/
+#define USB_ISTS_ITPI		BIT(10)
+/* Wakeup detected.*/
+#define USB_ISTS_WAKEI		BIT(11)
+/* Send Custom Packet detected.*/
+#define USB_ISTS_SPKTI		BIT(12)
+/* HS/FS mode connection detected.*/
+#define USB_ISTS_CON2I		BIT(16)
+/* HS/FS mode disconnection detected.*/
+#define USB_ISTS_DIS2I		BIT(17)
+/* USB reset (HS/FS mode) detected.*/
+#define USB_ISTS_U2RESI		BIT(18)
+/* LPM L2 state enter detected.*/
+#define USB_ISTS_L2ENTI		BIT(20)
+/* LPM  L2 state exit detected.*/
+#define USB_ISTS_L2EXTI		BIT(21)
+/* LPM L1 state enter detected.*/
+#define USB_ISTS_L1ENTI		BIT(24)
+/* LPM L1 state exit detected.*/
+#define USB_ISTS_L1EXTI		BIT(25)
+/* USB configuration reset detected.*/
+#define USB_ISTS_CFGRESI	BIT(26)
+/* Start of the USB warm reset detected.*/
+#define USB_ISTS_UWRESSI	BIT(28)
+/* End of the USB warm reset detected.*/
+#define USB_ISTS_UWRESEI	BIT(29)
+
+/* USB_SEL - bitmasks */
+#define EP_SEL_EPNO_MASK	GENMASK(3, 0)
+/* Endpoint number. */
+#define EP_SEL_EPNO(p)		((p) & EP_SEL_EPNO_MASK)
+/* Endpoint direction bit - 0 - OUT, 1 - IN. */
+#define EP_SEL_DIR		BIT(7)
+
+#define select_ep_in(nr)	(EP_SEL_EPNO(p) | EP_SEL_DIR)
+#define select_ep_out		(EP_SEL_EPNO(p))
+
+/* EP_TRADDR - bitmasks */
+/* Transfer Ring address. */
+#define EP_TRADDR_TRADDR(p)	((p))
+
+/* EP_CFG - bitmasks */
+/* Endpoint enable */
+#define EP_CFG_ENABLE		BIT(0)
+/*
+ *  Endpoint type.
+ * 1 - isochronous
+ * 2 - bulk
+ * 3 - interrupt
+ */
+#define EP_CFG_EPTYPE_MASK	GENMASK(2, 1)
+#define EP_CFG_EPTYPE(p)	(((p) << 1)  & EP_CFG_EPTYPE_MASK)
+/* Stream support enable (only in SS mode). */
+#define EP_CFG_STREAM_EN	BIT(3)
+/* TDL check (only in SS mode for BULK EP). */
+#define EP_CFG_TDL_CHK		BIT(4)
+/* SID check (only in SS mode for BULK OUT EP). */
+#define EP_CFG_SID_CHK		BIT(5)
+/* DMA transfer endianness. */
+#define EP_CFG_EPENDIAN		BIT(7)
+/* Max burst size (used only in SS mode). */
+#define EP_CFG_MAXBURST_MASK	GENMASK(11, 8)
+#define EP_CFG_MAXBURST(p)	(((p) << 8) & EP_CFG_MAXBURST_MASK)
+/* ISO max burst. */
+#define EP_CFG_MULT_MASK	GENMASK(15, 14)
+#define EP_CFG_MULT(p)		(((p) << 14) & EP_CFG_MULT_MASK)
+/* ISO max burst. */
+#define EP_CFG_MAXPKTSIZE_MASK	GENMASK(26, 16)
+#define EP_CFG_MAXPKTSIZE(p)	(((p) << 16) & EP_CFG_MAXPKTSIZE_MASK)
+/* Max number of buffered packets. */
+#define EP_CFG_BUFFERING_MASK	GENMASK(31, 27)
+#define EP_CFG_BUFFERING(p)	(((p) << 27) & EP_CFG_BUFFERING_MASK)
+
+/* EP_CMD - bitmasks */
+/* Endpoint reset. */
+#define EP_CMD_EPRST		BIT(0)
+/* Endpoint STALL set. */
+#define EP_CMD_SSTALL		BIT(1)
+/* Endpoint STALL clear. */
+#define EP_CMD_CSTALL		BIT(2)
+/* Send ERDY TP. */
+#define EP_CMD_ERDY		BIT(3)
+/* Request complete. */
+#define EP_CMD_REQ_CMPL		BIT(5)
+/* Transfer descriptor ready. */
+#define EP_CMD_DRDY		BIT(6)
+/* Data flush. */
+#define EP_CMD_DFLUSH		BIT(7)
+/*
+ * Transfer Descriptor Length write  (used only for Bulk Stream capable
+ * endpoints in SS mode).
+ * Bit Removed from DEV_VER_V3 controller version.
+ */
+#define EP_CMD_STDL		BIT(8)
+/*
+ * Transfer Descriptor Length (used only in SS mode for bulk endpoints).
+ * Bits Removed from DEV_VER_V3 controller version.
+ */
+#define EP_CMD_TDL_MASK		GENMASK(15, 9)
+#define EP_CMD_TDL_SET(p)	(((p) << 9) & EP_CMD_TDL_MASK)
+#define EP_CMD_TDL_GET(p)	(((p) & EP_CMD_TDL_MASK) >> 9)
+
+/* ERDY Stream ID value (used in SS mode). */
+#define EP_CMD_ERDY_SID_MASK	GENMASK(31, 16)
+#define EP_CMD_ERDY_SID(p)	(((p) << 16) & EP_CMD_ERDY_SID_MASK)
+
+/* EP_STS - bitmasks */
+/* Setup transfer complete. */
+#define EP_STS_SETUP		BIT(0)
+/* Endpoint STALL status. */
+#define EP_STS_STALL(p)		((p) & BIT(1))
+/* Interrupt On Complete. */
+#define EP_STS_IOC		BIT(2)
+/* Interrupt on Short Packet. */
+#define EP_STS_ISP		BIT(3)
+/* Transfer descriptor missing. */
+#define EP_STS_DESCMIS		BIT(4)
+/* Stream Rejected (used only in SS mode) */
+#define EP_STS_STREAMR		BIT(5)
+/* EXIT from MOVE DATA State (used only for stream transfers in SS mode). */
+#define EP_STS_MD_EXIT		BIT(6)
+/* TRB error. */
+#define EP_STS_TRBERR		BIT(7)
+/* Not ready (used only in SS mode). */
+#define EP_STS_NRDY		BIT(8)
+/* DMA busy bit. */
+#define EP_STS_DBUSY		BIT(9)
+/* Endpoint Buffer Empty */
+#define EP_STS_BUFFEMPTY(p)	((p) & BIT(10))
+/* Current Cycle Status */
+#define EP_STS_CCS(p)		((p) & BIT(11))
+/* Prime (used only in SS mode. */
+#define EP_STS_PRIME		BIT(12)
+/* Stream error (used only in SS mode). */
+#define EP_STS_SIDERR		BIT(13)
+/* OUT size mismatch. */
+#define EP_STS_OUTSMM		BIT(14)
+/* ISO transmission error. */
+#define EP_STS_ISOERR		BIT(15)
+/* Host Packet Pending (only for SS mode). */
+#define EP_STS_HOSTPP(p)	((p) & BIT(16))
+/* Stream Protocol State Machine State (only for Bulk stream endpoints). */
+#define EP_STS_SPSMST_MASK		GENMASK(18, 17)
+#define EP_STS_SPSMST_DISABLED(p)	(((p) & EP_STS_SPSMST_MASK) >> 17)
+#define EP_STS_SPSMST_IDLE(p)		(((p) & EP_STS_SPSMST_MASK) >> 17)
+#define EP_STS_SPSMST_START_STREAM(p)	(((p) & EP_STS_SPSMST_MASK) >> 17)
+#define EP_STS_SPSMST_MOVE_DATA(p)	(((p) & EP_STS_SPSMST_MASK) >> 17)
+/* Interrupt On Transfer complete. */
+#define EP_STS_IOT		BIT(19)
+/* OUT queue endpoint number. */
+#define EP_STS_OUTQ_NO_MASK	GENMASK(27, 24)
+#define EP_STS_OUTQ_NO(p)	(((p) & EP_STS_OUTQ_NO_MASK) >> 24)
+/* OUT queue valid flag. */
+#define EP_STS_OUTQ_VAL_MASK	BIT(28)
+#define EP_STS_OUTQ_VAL(p)	((p) & EP_STS_OUTQ_VAL_MASK)
+/* SETUP WAIT. */
+#define EP_STS_STPWAIT		BIT(31)
+
+/* EP_STS_SID - bitmasks */
+/* Stream ID (used only in SS mode). */
+#define EP_STS_SID_MASK		GENMASK(15, 0)
+#define EP_STS_SID(p)		((p) & EP_STS_SID_MASK)
+
+/* EP_STS_EN - bitmasks */
+/* SETUP interrupt enable. */
+#define EP_STS_EN_SETUPEN	BIT(0)
+/* OUT transfer missing descriptor enable. */
+#define EP_STS_EN_DESCMISEN	BIT(4)
+/* Stream Rejected enable. */
+#define EP_STS_EN_STREAMREN	BIT(5)
+/* Move Data Exit enable.*/
+#define EP_STS_EN_MD_EXITEN	BIT(6)
+/* TRB enable. */
+#define EP_STS_EN_TRBERREN	BIT(7)
+/* NRDY enable. */
+#define EP_STS_EN_NRDYEN	BIT(8)
+/* Prime enable. */
+#define EP_STS_EN_PRIMEEEN	BIT(12)
+/* Stream error enable. */
+#define EP_STS_EN_SIDERREN	BIT(13)
+/* OUT size mismatch enable. */
+#define EP_STS_EN_OUTSMMEN	BIT(14)
+/* ISO transmission error enable. */
+#define EP_STS_EN_ISOERREN	BIT(15)
+/* Interrupt on Transmission complete enable. */
+#define EP_STS_EN_IOTEN		BIT(19)
+/* Setup Wait interrupt enable. */
+#define EP_STS_EN_STPWAITEN	BIT(31)
+
+/* DRBL- bitmasks */
+#define DB_VALUE_BY_INDEX(index) (1 << (index))
+#define DB_VALUE_EP0_OUT	BIT(0)
+#define DB_VALUE_EP0_IN		BIT(16)
+
+/* EP_IEN - bitmasks */
+#define EP_IEN(index)		(1 << (index))
+#define EP_IEN_EP_OUT0		BIT(0)
+#define EP_IEN_EP_IN0		BIT(16)
+
+/* EP_ISTS - bitmasks */
+#define EP_ISTS(index)		(1 << (index))
+#define EP_ISTS_EP_OUT0		BIT(0)
+#define EP_ISTS_EP_IN0		BIT(16)
+
+/* USB_PWR- bitmasks */
+/*Power Shut Off capability enable*/
+#define PUSB_PWR_PSO_EN		BIT(0)
+/*Power Shut Off capability disable*/
+#define PUSB_PWR_PSO_DS		BIT(1)
+/*
+ * Enables turning-off Reference Clock.
+ * This bit is optional and implemented only when support for OTG is
+ * implemented (indicated by OTG_READY bit set to '1').
+ */
+#define PUSB_PWR_STB_CLK_SWITCH_EN	BIT(8)
+/*
+ * Status bit indicating that operation required by STB_CLK_SWITCH_EN write
+ * is completed
+ */
+#define PUSB_PWR_STB_CLK_SWITCH_DONE	BIT(9)
+/* This bit informs if Fast Registers Access is enabled. */
+#define PUSB_PWR_FST_REG_ACCESS_STAT	BIT(30)
+/* Fast Registers Access Enable. */
+#define PUSB_PWR_FST_REG_ACCESS		BIT(31)
+
+/* USB_CONF2- bitmasks */
+/*
+ * Writing 1 disables TDL calculation basing on TRB feature in controller
+ * for DMULT mode.
+ * Bit supported only for DEV_VER_V2 version.
+ */
+#define USB_CONF2_DIS_TDL_TRB		BIT(1)
+/*
+ * Writing 1 enables TDL calculation basing on TRB feature in controller
+ * for DMULT mode.
+ * Bit supported only for DEV_VER_V2 version.
+ */
+#define USB_CONF2_EN_TDL_TRB		BIT(2)
+
+/* USB_CAP1- bitmasks */
+/*
+ * SFR Interface type
+ * These field reflects type of SFR interface implemented:
+ * 0x0 - OCP
+ * 0x1 - AHB,
+ * 0x2 - PLB
+ * 0x3 - AXI
+ * 0x4-0xF - reserved
+ */
+#define USB_CAP1_SFR_TYPE_MASK	GENMASK(3, 0)
+#define DEV_SFR_TYPE_OCP(p)	(((p) & USB_CAP1_SFR_TYPE_MASK) == 0x0)
+#define DEV_SFR_TYPE_AHB(p)	(((p) & USB_CAP1_SFR_TYPE_MASK) == 0x1)
+#define DEV_SFR_TYPE_PLB(p)	(((p) & USB_CAP1_SFR_TYPE_MASK) == 0x2)
+#define DEV_SFR_TYPE_AXI(p)	(((p) & USB_CAP1_SFR_TYPE_MASK) == 0x3)
+/*
+ * SFR Interface width
+ * These field reflects width of SFR interface implemented:
+ * 0x0 - 8 bit interface,
+ * 0x1 - 16 bit interface,
+ * 0x2 - 32 bit interface
+ * 0x3 - 64 bit interface
+ * 0x4-0xF - reserved
+ */
+#define USB_CAP1_SFR_WIDTH_MASK	GENMASK(7, 4)
+#define DEV_SFR_WIDTH_8(p)	(((p) & USB_CAP1_SFR_WIDTH_MASK) == (0x0 << 4))
+#define DEV_SFR_WIDTH_16(p)	(((p) & USB_CAP1_SFR_WIDTH_MASK) == (0x1 << 4))
+#define DEV_SFR_WIDTH_32(p)	(((p) & USB_CAP1_SFR_WIDTH_MASK) == (0x2 << 4))
+#define DEV_SFR_WIDTH_64(p)	(((p) & USB_CAP1_SFR_WIDTH_MASK) == (0x3 << 4))
+/*
+ * DMA Interface type
+ * These field reflects type of DMA interface implemented:
+ * 0x0 - OCP
+ * 0x1 - AHB,
+ * 0x2 - PLB
+ * 0x3 - AXI
+ * 0x4-0xF - reserved
+ */
+#define USB_CAP1_DMA_TYPE_MASK	GENMASK(11, 8)
+#define DEV_DMA_TYPE_OCP(p)	(((p) & USB_CAP1_DMA_TYPE_MASK) == (0x0 << 8))
+#define DEV_DMA_TYPE_AHB(p)	(((p) & USB_CAP1_DMA_TYPE_MASK) == (0x1 << 8))
+#define DEV_DMA_TYPE_PLB(p)	(((p) & USB_CAP1_DMA_TYPE_MASK) == (0x2 << 8))
+#define DEV_DMA_TYPE_AXI(p)	(((p) & USB_CAP1_DMA_TYPE_MASK) == (0x3 << 8))
+/*
+ * DMA Interface width
+ * These field reflects width of DMA interface implemented:
+ * 0x0 - reserved,
+ * 0x1 - reserved,
+ * 0x2 - 32 bit interface
+ * 0x3 - 64 bit interface
+ * 0x4-0xF - reserved
+ */
+#define USB_CAP1_DMA_WIDTH_MASK	GENMASK(15, 12)
+#define DEV_DMA_WIDTH_32(p)	(((p) & USB_CAP1_DMA_WIDTH_MASK) == (0x2 << 12))
+#define DEV_DMA_WIDTH_64(p)	(((p) & USB_CAP1_DMA_WIDTH_MASK) == (0x3 << 12))
+/*
+ * USB3 PHY Interface type
+ * These field reflects type of USB3 PHY interface implemented:
+ * 0x0 - USB PIPE,
+ * 0x1 - RMMI,
+ * 0x2-0xF - reserved
+ */
+#define USB_CAP1_U3PHY_TYPE_MASK GENMASK(19, 16)
+#define DEV_U3PHY_PIPE(p) (((p) & USB_CAP1_U3PHY_TYPE_MASK) == (0x0 << 16))
+#define DEV_U3PHY_RMMI(p) (((p) & USB_CAP1_U3PHY_TYPE_MASK) == (0x1 << 16))
+/*
+ * USB3 PHY Interface width
+ * These field reflects width of USB3 PHY interface implemented:
+ * 0x0 - 8 bit PIPE interface,
+ * 0x1 - 16 bit PIPE interface,
+ * 0x2 - 32 bit PIPE interface,
+ * 0x3 - 64 bit PIPE interface
+ * 0x4-0xF - reserved
+ * Note: When SSIC interface is implemented this field shows the width of
+ * internal PIPE interface. The RMMI interface is always 20bit wide.
+ */
+#define USB_CAP1_U3PHY_WIDTH_MASK GENMASK(23, 20)
+#define DEV_U3PHY_WIDTH_8(p) \
+	(((p) & USB_CAP1_U3PHY_WIDTH_MASK) == (0x0 << 20))
+#define DEV_U3PHY_WIDTH_16(p) \
+	(((p) & USB_CAP1_U3PHY_WIDTH_MASK) == (0x1 << 16))
+#define DEV_U3PHY_WIDTH_32(p) \
+	(((p) & USB_CAP1_U3PHY_WIDTH_MASK) == (0x2 << 20))
+#define DEV_U3PHY_WIDTH_64(p) \
+	(((p) & USB_CAP1_U3PHY_WIDTH_MASK) == (0x3 << 16))
+
+/*
+ * USB2 PHY Interface enable
+ * These field informs if USB2 PHY interface is implemented:
+ * 0x0 - interface NOT implemented,
+ * 0x1 - interface implemented
+ */
+#define USB_CAP1_U2PHY_EN(p)	((p) & BIT(24))
+/*
+ * USB2 PHY Interface type
+ * These field reflects type of USB2 PHY interface implemented:
+ * 0x0 - UTMI,
+ * 0x1 - ULPI
+ */
+#define DEV_U2PHY_ULPI(p)	((p) & BIT(25))
+/*
+ * USB2 PHY Interface width
+ * These field reflects width of USB2 PHY interface implemented:
+ * 0x0 - 8 bit interface,
+ * 0x1 - 16 bit interface,
+ * Note: The ULPI interface is always 8bit wide.
+ */
+#define DEV_U2PHY_WIDTH_16(p)	((p) & BIT(26))
+/*
+ * OTG Ready
+ * 0x0 - pure device mode
+ * 0x1 - some features and ports for CDNS USB OTG controller are implemented.
+ */
+#define USB_CAP1_OTG_READY(p)	((p) & BIT(27))
+
+/*
+ * When set, indicates that controller supports automatic internal TDL
+ * calculation basing on the size provided in TRB (TRB[22:17]) for DMULT mode
+ * Supported only for DEV_VER_V2 controller version.
+ */
+#define USB_CAP1_TDL_FROM_TRB(p)	((p) & BIT(28))
+
+/* USB_CAP2- bitmasks */
+/*
+ * The actual size of the connected On-chip RAM memory in kB:
+ * - 0 means 256 kB (max supported mem size)
+ * - value other than 0 reflects the mem size in kB
+ */
+#define USB_CAP2_ACTUAL_MEM_SIZE(p) ((p) & GENMASK(7, 0))
+/*
+ * Max supported mem size
+ * These field reflects width of on-chip RAM address bus width,
+ * which determines max supported mem size:
+ * 0x0-0x7 - reserved,
+ * 0x8 - support for 4kB mem,
+ * 0x9 - support for 8kB mem,
+ * 0xA - support for 16kB mem,
+ * 0xB - support for 32kB mem,
+ * 0xC - support for 64kB mem,
+ * 0xD - support for 128kB mem,
+ * 0xE - support for 256kB mem,
+ * 0xF - reserved
+ */
+#define USB_CAP2_MAX_MEM_SIZE(p) ((p) & GENMASK(11, 8))
+
+/* USB_CAP3- bitmasks */
+#define EP_IS_IMPLEMENTED(reg, index) ((reg) & (1 << (index)))
+
+/* USB_CAP4- bitmasks */
+#define EP_SUPPORT_ISO(reg, index) ((reg) & (1 << (index)))
+
+/* USB_CAP5- bitmasks */
+#define EP_SUPPORT_STREAM(reg, index) ((reg) & (1 << (index)))
+
+/* USB_CAP6- bitmasks */
+/* The USBSS-DEV Controller  Internal build number. */
+#define GET_DEV_BASE_VERSION(p) ((p) & GENMASK(23, 0))
+/* The USBSS-DEV Controller version number. */
+#define GET_DEV_CUSTOM_VERSION(p) ((p) & GENMASK(31, 24))
+
+#define DEV_VER_NXP_V1		0x00024502
+#define DEV_VER_TI_V1		0x00024509
+#define DEV_VER_V2		0x0002450C
+#define DEV_VER_V3		0x0002450d
+
+/* DBG_LINK1- bitmasks */
+/*
+ * LFPS_MIN_DET_U1_EXIT value This parameter configures the minimum
+ * time required for decoding the received LFPS as an LFPS.U1_Exit.
+ */
+#define DBG_LINK1_LFPS_MIN_DET_U1_EXIT(p)	((p) & GENMASK(7, 0))
+/*
+ * LFPS_MIN_GEN_U1_EXIT value This parameter configures the minimum time for
+ * phytxelecidle deassertion when LFPS.U1_Exit
+ */
+#define DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_MASK	GENMASK(15, 8)
+#define DBG_LINK1_LFPS_MIN_GEN_U1_EXIT(p)	(((p) << 8) & GENMASK(15, 8))
+/*
+ * RXDET_BREAK_DIS value This parameter configures terminating the Far-end
+ * Receiver termination detection sequence:
+ * 0: it is possible that USBSS_DEV will terminate Farend receiver
+ *    termination detection sequence
+ * 1: USBSS_DEV will not terminate Far-end receiver termination
+ *    detection sequence
+ */
+#define DBG_LINK1_RXDET_BREAK_DIS		BIT(16)
+/* LFPS_GEN_PING value This parameter configures the LFPS.Ping generation */
+#define DBG_LINK1_LFPS_GEN_PING(p)		(((p) << 17) & GENMASK(21, 17))
+/*
+ * Set the LFPS_MIN_DET_U1_EXIT value Writing '1' to this bit writes the
+ * LFPS_MIN_DET_U1_EXIT field value to the device. This bit is automatically
+ * cleared. Writing '0' has no effect
+ */
+#define DBG_LINK1_LFPS_MIN_DET_U1_EXIT_SET	BIT(24)
+/*
+ * Set the LFPS_MIN_GEN_U1_EXIT value. Writing '1' to this bit writes the
+ * LFPS_MIN_GEN_U1_EXIT field value to the device. This bit is automatically
+ * cleared. Writing '0' has no effect
+ */
+#define DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_SET	BIT(25)
+/*
+ * Set the RXDET_BREAK_DIS value Writing '1' to this bit writes
+ * the RXDET_BREAK_DIS field value to the device. This bit is automatically
+ * cleared. Writing '0' has no effect
+ */
+#define DBG_LINK1_RXDET_BREAK_DIS_SET		BIT(26)
+/*
+ * Set the LFPS_GEN_PING_SET value Writing '1' to this bit writes
+ * the LFPS_GEN_PING field value to the device. This bit is automatically
+ * cleared. Writing '0' has no effect."
+ */
+#define DBG_LINK1_LFPS_GEN_PING_SET		BIT(27)
+
+/* DMA_AXI_CTRL- bitmasks */
+/* The mawprot pin configuration. */
+#define DMA_AXI_CTRL_MARPROT(p) ((p) & GENMASK(2, 0))
+/* The marprot pin configuration. */
+#define DMA_AXI_CTRL_MAWPROT(p) (((p) & GENMASK(2, 0)) << 16)
+#define DMA_AXI_CTRL_NON_SECURE 0x02
+
+#define gadget_to_cdns3_device(g) (container_of(g, struct cdns3_device, gadget))
+
+#define ep_to_cdns3_ep(ep) (container_of(ep, struct cdns3_endpoint, endpoint))
+
+/*-------------------------------------------------------------------------*/
+/*
+ * USBSS-DEV DMA interface.
+ */
+#define TRBS_PER_SEGMENT	40
+
+#define ISO_MAX_INTERVAL	10
+
+#if TRBS_PER_SEGMENT < 2
+#error "Incorrect TRBS_PER_SEGMENT. Minimal Transfer Ring size is 2."
+#endif
+
+/*
+ *Only for ISOC endpoints - maximum number of TRBs is calculated as
+ * pow(2, bInterval-1) * number of usb requests. It is limitation made by
+ * driver to save memory. Controller must prepare TRB for each ITP even
+ * if bInterval > 1. It's the reason why driver needs so many TRBs for
+ * isochronous endpoints.
+ */
+#define TRBS_PER_ISOC_SEGMENT	(ISO_MAX_INTERVAL * 8)
+
+#define GET_TRBS_PER_SEGMENT(ep_type) ((ep_type) == USB_ENDPOINT_XFER_ISOC ? \
+				      TRBS_PER_ISOC_SEGMENT : TRBS_PER_SEGMENT)
+/**
+ * struct cdns3_trb - represent Transfer Descriptor block.
+ * @buffer:	pointer to buffer data
+ * @length:	length of data
+ * @control:	control flags.
+ *
+ * This structure describes transfer block serviced by DMA module.
+ */
+struct cdns3_trb {
+	__le32 buffer;
+	__le32 length;
+	__le32 control;
+};
+
+#define TRB_SIZE		(sizeof(struct cdns3_trb))
+#define TRB_RING_SIZE		(TRB_SIZE * TRBS_PER_SEGMENT)
+#define TRB_ISO_RING_SIZE	(TRB_SIZE * TRBS_PER_ISOC_SEGMENT)
+#define TRB_CTRL_RING_SIZE	(TRB_SIZE * 2)
+
+/* TRB bit mask */
+#define TRB_TYPE_BITMASK	GENMASK(15, 10)
+#define TRB_TYPE(p)		((p) << 10)
+#define TRB_FIELD_TO_TYPE(p)	(((p) & TRB_TYPE_BITMASK) >> 10)
+
+/* TRB type IDs */
+/* bulk, interrupt, isoc , and control data stage */
+#define TRB_NORMAL		1
+/* TRB for linking ring segments */
+#define TRB_LINK		6
+
+/* Cycle bit - indicates TRB ownership by driver or hw*/
+#define TRB_CYCLE		BIT(0)
+/*
+ * When set to '1', the device will toggle its interpretation of the Cycle bit
+ */
+#define TRB_TOGGLE		BIT(1)
+
+/*
+ * Short Packet (SP). OUT EPs at DMULT=1 only. Indicates if the TRB was
+ * processed while USB short packet was received. No more buffers defined by
+ * the TD will be used. DMA will automatically advance to next TD.
+ * - Shall be set to 0 by Software when putting TRB on the Transfer Ring
+ * - Shall be set to 1 by Controller when Short Packet condition for this TRB
+ *   is detected independent if ISP is set or not.
+ */
+#define TRB_SP			BIT(1)
+
+/* Interrupt on short packet*/
+#define TRB_ISP			BIT(2)
+/*Setting this bit enables FIFO DMA operation mode*/
+#define TRB_FIFO_MODE		BIT(3)
+/* Set PCIe no snoop attribute */
+#define TRB_CHAIN		BIT(4)
+/* Interrupt on completion */
+#define TRB_IOC			BIT(5)
+
+/* stream ID bitmasks. */
+#define TRB_STREAM_ID_BITMASK		GENMASK(31, 16)
+#define TRB_STREAM_ID(p)		((p) << 16)
+#define TRB_FIELD_TO_STREAMID(p)	(((p) & TRB_STREAM_ID_BITMASK) >> 16)
+
+/* Size of TD expressed in USB packets for HS/FS mode. */
+#define TRB_TDL_HS_SIZE(p)	(((p) << 16) & GENMASK(31, 16))
+#define TRB_TDL_HS_SIZE_GET(p)	(((p) & GENMASK(31, 16)) >> 16)
+
+/* transfer_len bitmasks. */
+#define TRB_LEN(p)		((p) & GENMASK(16, 0))
+
+/* Size of TD expressed in USB packets for SS mode. */
+#define TRB_TDL_SS_SIZE(p)	(((p) << 17) & GENMASK(23, 17))
+#define TRB_TDL_SS_SIZE_GET(p)	(((p) & GENMASK(23, 17)) >> 17)
+
+/* transfer_len bitmasks - bits 31:24 */
+#define TRB_BURST_LEN(p)	(((p) << 24) & GENMASK(31, 24))
+#define TRB_BURST_LEN_GET(p)	(((p) & GENMASK(31, 24)) >> 24)
+
+/* Data buffer pointer bitmasks*/
+#define TRB_BUFFER(p)		((p) & GENMASK(31, 0))
+
+/*-------------------------------------------------------------------------*/
+/* Driver numeric constants */
+
+/* Such declaration should be added to ch9.h */
+#define USB_DEVICE_MAX_ADDRESS		127
+
+/* Endpoint init values */
+#define CDNS3_EP_MAX_PACKET_LIMIT	1024
+#define CDNS3_EP_MAX_STREAMS		15
+#define CDNS3_EP0_MAX_PACKET_LIMIT	512
+
+/* All endpoints including EP0 */
+#define CDNS3_ENDPOINTS_MAX_COUNT	32
+#define CDNS3_EP_ZLP_BUF_SIZE		1024
+
+#define CDNS3_EP_BUF_SIZE		2	/* KB */
+#define CDNS3_EP_ISO_HS_MULT		3
+#define CDNS3_EP_ISO_SS_BURST		3
+#define CDNS3_MAX_NUM_DESCMISS_BUF	32
+#define CDNS3_DESCMIS_BUF_SIZE		2048	/* Bytes */
+#define CDNS3_WA2_NUM_BUFFERS		128
+/*-------------------------------------------------------------------------*/
+/* Used structs */
+
+struct cdns3_device;
+
+/**
+ * struct cdns3_endpoint - extended device side representation of USB endpoint.
+ * @endpoint: usb endpoint
+ * @pending_req_list: list of requests queuing on transfer ring.
+ * @deferred_req_list: list of requests waiting for queuing on transfer ring.
+ * @wa2_descmiss_req_list: list of requests internally allocated by driver.
+ * @trb_pool: transfer ring - array of transaction buffers
+ * @trb_pool_dma: dma address of transfer ring
+ * @cdns3_dev: device associated with this endpoint
+ * @name: a human readable name e.g. ep1out
+ * @flags: specify the current state of endpoint
+ * @descmis_req: internal transfer object used for getting data from on-chip
+ *     buffer. It can happen only if function driver doesn't send usb_request
+ *     object on time.
+ * @dir: endpoint direction
+ * @num: endpoint number (1 - 15)
+ * @type: set to bmAttributes & USB_ENDPOINT_XFERTYPE_MASK
+ * @interval: interval between packets used for ISOC endpoint.
+ * @free_trbs: number of free TRBs in transfer ring
+ * @num_trbs: number of all TRBs in transfer ring
+ * @pcs: producer cycle state
+ * @ccs: consumer cycle state
+ * @enqueue: enqueue index in transfer ring
+ * @dequeue: dequeue index in transfer ring
+ * @trb_burst_size: number of burst used in trb.
+ */
+struct cdns3_endpoint {
+	struct usb_ep		endpoint;
+	struct list_head	pending_req_list;
+	struct list_head	deferred_req_list;
+	struct list_head	wa2_descmiss_req_list;
+	int			wa2_counter;
+
+	struct cdns3_trb	*trb_pool;
+	dma_addr_t		trb_pool_dma;
+
+	struct cdns3_device	*cdns3_dev;
+	char			name[20];
+
+#define EP_ENABLED		BIT(0)
+#define EP_STALLED		BIT(1)
+#define EP_STALL_PENDING	BIT(2)
+#define EP_WEDGE		BIT(3)
+#define EP_TRANSFER_STARTED	BIT(4)
+#define EP_UPDATE_EP_TRBADDR	BIT(5)
+#define EP_PENDING_REQUEST	BIT(6)
+#define EP_RING_FULL		BIT(7)
+#define EP_CLAIMED		BIT(8)
+#define EP_DEFERRED_DRDY	BIT(9)
+#define EP_QUIRK_ISO_OUT_EN	BIT(10)
+#define EP_QUIRK_END_TRANSFER	BIT(11)
+#define EP_QUIRK_EXTRA_BUF_DET	BIT(12)
+#define EP_QUIRK_EXTRA_BUF_EN	BIT(13)
+	u32			flags;
+
+	struct cdns3_request	*descmis_req;
+
+	u8			dir;
+	u8			num;
+	u8			type;
+	int			interval;
+
+	int			free_trbs;
+	int			num_trbs;
+	u8			pcs;
+	u8			ccs;
+	int			enqueue;
+	int			dequeue;
+	u8			trb_burst_size;
+
+	unsigned int		wa1_set:1;
+	struct cdns3_trb	*wa1_trb;
+	unsigned int		wa1_trb_index;
+	unsigned int		wa1_cycle_bit:1;
+};
+
+/**
+ * struct cdns3_aligned_buf - represent aligned buffer used for DMA transfer
+ * @buf: aligned to 8 bytes data buffer. Buffer address used in
+ *       TRB shall be aligned to 8.
+ * @dma: dma address
+ * @size: size of buffer
+ * @in_use: inform if this buffer is associated with usb_request
+ * @list: used to adding instance of this object to list
+ */
+struct cdns3_aligned_buf {
+	void			*buf;
+	dma_addr_t		dma;
+	u32			size;
+	int			in_use:1;
+	struct list_head	list;
+};
+
+/**
+ * struct cdns3_request - extended device side representation of usb_request
+ *                        object .
+ * @request: generic usb_request object describing single I/O request.
+ * @priv_ep: extended representation of usb_ep object
+ * @trb: the first TRB association with this request
+ * @start_trb: number of the first TRB in transfer ring
+ * @end_trb: number of the last TRB in transfer ring
+ * @aligned_buf: object holds information about aligned buffer associated whit
+ *               this endpoint
+ * @flags: flag specifying special usage of request
+ * @list: used by internally allocated request to add to wa2_descmiss_req_list.
+ */
+struct cdns3_request {
+	struct usb_request		request;
+	struct cdns3_endpoint		*priv_ep;
+	struct cdns3_trb		*trb;
+	int				start_trb;
+	int				end_trb;
+	struct cdns3_aligned_buf	*aligned_buf;
+#define REQUEST_PENDING			BIT(0)
+#define REQUEST_INTERNAL		BIT(1)
+#define REQUEST_INTERNAL_CH		BIT(2)
+#define REQUEST_ZLP			BIT(3)
+#define REQUEST_UNALIGNED		BIT(4)
+	u32				flags;
+	struct list_head		list;
+};
+
+#define to_cdns3_request(r) (container_of(r, struct cdns3_request, request))
+
+/*Stages used during enumeration process.*/
+#define CDNS3_SETUP_STAGE		0x0
+#define CDNS3_DATA_STAGE		0x1
+#define CDNS3_STATUS_STAGE		0x2
+
+/**
+ * struct cdns3_device - represent USB device.
+ * @dev: pointer to device structure associated whit this controller
+ * @sysdev: pointer to the DMA capable device
+ * @gadget: device side representation of the peripheral controller
+ * @gadget_driver: pointer to the gadget driver
+ * @dev_ver: device controller version.
+ * @lock: for synchronizing
+ * @regs: base address for device side registers
+ * @setup_buf: used while processing usb control requests
+ * @setup_dma: dma address for setup_buf
+ * @zlp_buf - zlp buffer
+ * @ep0_stage: ep0 stage during enumeration process.
+ * @ep0_data_dir: direction for control transfer
+ * @eps: array of pointers to all endpoints with exclusion ep0
+ * @aligned_buf_list: list of aligned buffers internally allocated by driver
+ * @aligned_buf_wq: workqueue freeing  no longer used aligned buf.
+ * @selected_ep: actually selected endpoint. It's used only to improve
+ *               performance.
+ * @isoch_delay: value from Set Isoch Delay request. Only valid on SS/SSP.
+ * @u1_allowed: allow device transition to u1 state
+ * @u2_allowed: allow device transition to u2 state
+ * @is_selfpowered: device is self powered
+ * @setup_pending: setup packet is processing by gadget driver
+ * @hw_configured_flag: hardware endpoint configuration was set.
+ * @wake_up_flag: allow device to remote up the host
+ * @status_completion_no_call: indicate that driver is waiting for status s
+ *     stage completion. It's used in deferred SET_CONFIGURATION request.
+ * @onchip_buffers: number of available on-chip buffers.
+ * @onchip_used_size: actual size of on-chip memory assigned to endpoints.
+ * @pending_status_wq: workqueue handling status stage for deferred requests.
+ * @pending_status_request: request for which status stage was deferred
+ */
+struct cdns3_device {
+	struct udevice			*dev;
+	struct udevice			*sysdev;
+
+	struct usb_gadget		gadget;
+	struct usb_gadget_driver	*gadget_driver;
+
+#define CDNS_REVISION_V0		0x00024501
+#define CDNS_REVISION_V1		0x00024509
+	u32				dev_ver;
+
+	/* generic spin-lock for drivers */
+	spinlock_t			lock;
+
+	struct cdns3_usb_regs		__iomem *regs;
+
+	struct usb_ctrlrequest		*setup_buf;
+	dma_addr_t			setup_dma;
+	void				*zlp_buf;
+
+	u8				ep0_stage;
+	int				ep0_data_dir;
+
+	struct cdns3_endpoint		*eps[CDNS3_ENDPOINTS_MAX_COUNT];
+
+	struct list_head		aligned_buf_list;
+	struct work_struct		aligned_buf_wq;
+
+	u32				selected_ep;
+	u16				isoch_delay;
+
+	unsigned			wait_for_setup:1;
+	unsigned			u1_allowed:1;
+	unsigned			u2_allowed:1;
+	unsigned			is_selfpowered:1;
+	unsigned			setup_pending:1;
+	int				hw_configured_flag:1;
+	int				wake_up_flag:1;
+	unsigned			status_completion_no_call:1;
+	int				out_mem_is_allocated;
+
+	struct work_struct		pending_status_wq;
+	struct usb_request		*pending_status_request;
+
+	/*in KB */
+	u32				onchip_buffers;
+	u16				onchip_used_size;
+};
+
+void cdns3_set_register_bit(void __iomem *ptr, u32 mask);
+dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
+				 struct cdns3_trb *trb);
+enum usb_device_speed cdns3_get_speed(struct cdns3_device *priv_dev);
+void cdns3_pending_setup_status_handler(struct work_struct *work);
+void cdns3_hw_reset_eps_config(struct cdns3_device *priv_dev);
+void cdns3_set_hw_configuration(struct cdns3_device *priv_dev);
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep);
+void cdns3_allow_enable_l1(struct cdns3_device *priv_dev, int enable);
+struct usb_request *cdns3_next_request(struct list_head *list);
+int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+			  struct usb_request *request);
+void cdns3_rearm_transfer(struct cdns3_endpoint *priv_ep, u8 rearm);
+int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep);
+u8 cdns3_ep_addr_to_index(u8 ep_addr);
+int cdns3_gadget_ep_set_wedge(struct usb_ep *ep);
+int cdns3_gadget_ep_set_halt(struct usb_ep *ep, int value);
+void __cdns3_gadget_ep_set_halt(struct cdns3_endpoint *priv_ep);
+int __cdns3_gadget_ep_clear_halt(struct cdns3_endpoint *priv_ep);
+struct usb_request *cdns3_gadget_ep_alloc_request(struct usb_ep *ep,
+						  gfp_t gfp_flags);
+void cdns3_gadget_ep_free_request(struct usb_ep *ep,
+				  struct usb_request *request);
+int cdns3_gadget_ep_dequeue(struct usb_ep *ep, struct usb_request *request);
+void cdns3_gadget_giveback(struct cdns3_endpoint *priv_ep,
+			   struct cdns3_request *priv_req,
+			   int status);
+
+int cdns3_init_ep0(struct cdns3_device *priv_dev,
+		   struct cdns3_endpoint *priv_ep);
+void cdns3_ep0_config(struct cdns3_device *priv_dev);
+void cdns3_ep_config(struct cdns3_endpoint *priv_ep);
+void cdns3_check_ep0_interrupt_proceed(struct cdns3_device *priv_dev, int dir);
+int __cdns3_gadget_wakeup(struct cdns3_device *priv_dev);
+
+#endif /* __LINUX_CDNS3_GADGET */
diff --git a/drivers/usb/cdns3/host-export.h b/drivers/usb/cdns3/host-export.h
new file mode 100644
index 0000000..b498a17
--- /dev/null
+++ b/drivers/usb/cdns3/host-export.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Cadence USBSS DRD Driver - Host Export APIs
+ *
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Peter Chen <peter.chen@nxp.com>
+ */
+#ifndef __LINUX_CDNS3_HOST_EXPORT
+#define __LINUX_CDNS3_HOST_EXPORT
+
+#ifdef CONFIG_USB_CDNS3_HOST
+
+int cdns3_host_init(struct cdns3 *cdns);
+void cdns3_host_exit(struct cdns3 *cdns);
+
+#else
+
+static inline int cdns3_host_init(struct cdns3 *cdns)
+{
+	return -ENXIO;
+}
+
+static inline void cdns3_host_exit(struct cdns3 *cdns) { }
+
+#endif /* CONFIG_USB_CDNS3_HOST */
+
+#endif /* __LINUX_CDNS3_HOST_EXPORT */
diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
new file mode 100644
index 0000000..79be630
--- /dev/null
+++ b/drivers/usb/cdns3/host.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - host side
+ *
+ * Copyright (C) 2018-2019 Cadence Design Systems.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Peter Chen <peter.chen@nxp.com>
+ *          Pawel Laszczak <pawell@cadence.com>
+ */
+#include <dm.h>
+#include <linux/compat.h>
+#include <usb.h>
+#include "../host/xhci.h"
+
+#include "core.h"
+#include "drd.h"
+
+static int __cdns3_host_init(struct cdns3 *cdns)
+{
+	struct xhci_hcor *hcor;
+	struct xhci_hccr *hccr;
+
+	cdns3_drd_switch_host(cdns, 1);
+
+	hccr = (struct xhci_hccr *)cdns->xhci_regs;
+	hcor = (struct xhci_hcor *)(cdns->xhci_regs +
+			HC_LENGTH(xhci_readl(&(hccr)->cr_capbase)));
+
+	return xhci_register(cdns->dev, hccr, hcor);
+}
+
+static void cdns3_host_exit(struct cdns3 *cdns)
+{
+	xhci_deregister(cdns->dev);
+	cdns3_drd_switch_host(cdns, 0);
+}
+
+int cdns3_host_init(struct cdns3 *cdns)
+{
+	struct cdns3_role_driver *rdrv;
+
+	rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
+	if (!rdrv)
+		return -ENOMEM;
+
+	rdrv->start	= __cdns3_host_init;
+	rdrv->stop	= cdns3_host_exit;
+	rdrv->state	= CDNS3_ROLE_STATE_INACTIVE;
+	rdrv->name	= "host";
+
+	cdns->roles[USB_ROLE_HOST] = rdrv;
+
+	return 0;
+}
diff --git a/drivers/usb/cdns3/trace.c b/drivers/usb/cdns3/trace.c
new file mode 100644
index 0000000..459fa72
--- /dev/null
+++ b/drivers/usb/cdns3/trace.c
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USBSS device controller driver Trace Support
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ */
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
diff --git a/drivers/usb/cdns3/trace.h b/drivers/usb/cdns3/trace.h
new file mode 100644
index 0000000..e86c02a
--- /dev/null
+++ b/drivers/usb/cdns3/trace.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#define trace_cdns3_prepare_trb(a, b)
+#define trace_cdns3_doorbell_ep0(a, b)
+#define trace_cdns3_ctrl_req(a)
+#define trace_cdns3_complete_trb(a, b)
+#define trace_cdns3_ep0_irq(a, b)
+#define trace_cdns3_gadget_giveback(a)
+#define trace_cdns3_free_aligned_request(a)
+#define trace_cdns3_prepare_aligned_request(a)
+#define trace_cdns3_ring(a)
+#define trace_cdns3_doorbell_epx(a, b)
+#define trace_cdns3_request_handled(a, b, c)
+#define trace_cdns3_epx_irq(a, b)
+#define trace_cdns3_usb_irq(a, b)
+#define trace_cdns3_alloc_request(a)
+#define trace_cdns3_free_request(a)
+#define trace_cdns3_gadget_ep_enable(a)
+#define trace_cdns3_gadget_ep_disable(a)
+#define trace_cdns3_ep0_queue(a, b)
+#define trace_cdns3_ep0_dequeue(a)
+#define trace_cdns3_ep_queue(a)
+#define trace_cdns3_ep_dequeue(a)
+#define trace_cdns3_halt(a, b, c)
+#define trace_cdns3_wa1(a, b)
+#define trace_cdns3_wa2(a, b)