/**
 * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
 *
 * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
 *
 * Authors: Felipe Balbi <balbi@ti.com>,
 *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2  of
 * the License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/dma-mapping.h>

#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
#include <linux/usb/composite.h>
#endif
#include <linux/usb/samsung_usb.h>
#include <linux/phy/phy.h>
#include <linux/usb_notify.h>
#include <linux/workqueue.h>
#include <linux/ktime.h>

#include "debug.h"
#include "core.h"
#include "otg.h"
#include "gadget.h"
#include "io.h"
#ifdef CONFIG_USBIRQ_BALANCING_LTE_HIGHTP
#include <linux/netdevice.h>
#include <linux/cpu.h>
#include <linux/pm_qos.h>

int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask);

static struct notifier_block rndis_notifier;
static int gadget_irq = 0;
#endif

extern bool acc_dev_status;

#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
static void dwc3_disconnect_gadget(struct dwc3 *dwc);
static void dwc3_gadget_cable_connect(struct dwc3 *dwc, bool connect)
{
	static bool last_connect;
	struct usb_composite_dev *cdev;
	if (last_connect != connect) {
		if (!connect){
			cdev = get_gadget_data(&dwc->gadget);
			if (cdev != NULL) {
				cdev->mute_switch = 0;
				cdev->force_disconnect = 1;
				printk(KERN_DEBUG"Force Disconnect set to 1\n");
			}
		}
		last_connect = connect;
	}
}
#endif

#ifdef CONFIG_ARGOS
extern int argos_irq_affinity_setup_label(unsigned int irq, const char *label,
                 struct cpumask *affinity_cpu_mask,
                 struct cpumask *default_cpu_mask);
#ifdef CONFIG_SCHED_HMP
extern struct cpumask hmp_slow_cpu_mask;
static inline struct cpumask *get_default_cpu_mask(void)
{
	return &hmp_slow_cpu_mask;
}
#else
static inline struct cpumask *get_default_cpu_mask(void)
{
	return cpu_all_mask;
}
#endif
cpumask_var_t affinity_cpu_mask;
cpumask_var_t default_cpu_mask;
#endif

/**
 * dwc3_gadget_set_test_mode - Enables USB2 Test Modes
 * @dwc: pointer to our context structure
 * @mode: the mode to set (J, K SE0 NAK, Force Enable)
 *
 * Caller should take care of locking. This function will
 * return 0 on success or -EINVAL if wrong Test Selector
 * is passed
 */
int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
{
	u32		reg;

	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
	reg &= ~DWC3_DCTL_TSTCTRL_MASK;

	switch (mode) {
	case TEST_J:
	case TEST_K:
	case TEST_SE0_NAK:
	case TEST_PACKET:
	case TEST_FORCE_EN:
		reg |= mode << 1;
		break;
	default:
		return -EINVAL;
	}

	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	return 0;
}

/**
 * dwc3_gadget_get_link_state - Gets current state of USB Link
 * @dwc: pointer to our context structure
 *
 * Caller should take care of locking. This function will
 * return the link state on success (>= 0) or -ETIMEDOUT.
 */
int dwc3_gadget_get_link_state(struct dwc3 *dwc)
{
	u32		reg;

	reg = dwc3_readl(dwc->regs, DWC3_DSTS);

	return DWC3_DSTS_USBLNKST(reg);
}

/**
 * dwc3_gadget_set_link_state - Sets USB Link to a particular State
 * @dwc: pointer to our context structure
 * @state: the state to put link into
 *
 * Caller should take care of locking. This function will
 * return 0 on success or -ETIMEDOUT.
 */
int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
{
	int		retries = 10000;
	u32		reg;

	/*
	 * Wait until device controller is ready. Only applies to 1.94a and
	 * later RTL.
	 */
	if (dwc->revision >= DWC3_REVISION_194A) {
		while (--retries) {
			reg = dwc3_readl(dwc->regs, DWC3_DSTS);
			if (reg & DWC3_DSTS_DCNRD)
				udelay(5);
			else
				break;
		}

		if (retries <= 0)
			return -ETIMEDOUT;
	}

	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
	reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;

	/* set requested state */
	reg |= DWC3_DCTL_ULSTCHNGREQ(state);
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	/*
	 * The following code is racy when called from dwc3_gadget_wakeup,
	 * and is not needed, at least on newer versions
	 */
	if (dwc->revision >= DWC3_REVISION_194A)
		return 0;

	/* wait for a change in DSTS */
	retries = 10000;
	while (--retries) {
		reg = dwc3_readl(dwc->regs, DWC3_DSTS);

		if (DWC3_DSTS_USBLNKST(reg) == state)
			return 0;

		udelay(5);
	}

	dwc3_trace(trace_dwc3_gadget,
			"link state change request timed out");

	return -ETIMEDOUT;
}

/**
 * dwc3_gadget_resize_tx_fifos - reallocate fifo spaces for current use-case
 * @dwc: pointer to our context structure
 *
 * This function will a best effort FIFO allocation in order
 * to improve FIFO usage and throughput, while still allowing
 * us to enable as many endpoints as possible.
 *
 * Keep in mind that this operation will be highly dependent
 * on the configured size for RAM1 - which contains TxFifo -,
 * the amount of endpoints enabled on coreConsultant tool, and
 * the width of the Master Bus.
 *
 * In the ideal world, we would always be able to satisfy the
 * following equation:
 *
 * ((512 + 2 * MDWIDTH-Bytes) + (Number of IN Endpoints - 1) * \
 * (3 * (1024 + MDWIDTH-Bytes) + MDWIDTH-Bytes)) / MDWIDTH-Bytes
 *
 * Unfortunately, due to many variables that's not always the case.
 */
int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc)
{
	int		last_fifo_depth = 0;
	int		ram1_depth;
	int		fifo_size;
	int		mdwidth;
	int		num;

	if (!dwc->needs_fifo_resize)
		return 0;

	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
	mdwidth = DWC3_MDWIDTH(dwc->hwparams.hwparams0);

	/* MDWIDTH is represented in bits, we need it in bytes */
	mdwidth >>= 3;

	/*
	 * FIXME For now we will only allocate 1 wMaxPacketSize space
	 * for each enabled endpoint, later patches will come to
	 * improve this algorithm so that we better use the internal
	 * FIFO space
	 */
	for (num = 0; num < dwc->num_in_eps; num++) {
		/* bit0 indicates direction; 1 means IN ep */
		struct dwc3_ep	*dep = dwc->eps[(num << 1) | 1];
		int		mult = 1;
		int		tmp;

		if (!(dep->flags & DWC3_EP_ENABLED))
			continue;

		if (usb_endpoint_xfer_bulk(dep->endpoint.desc)
				|| usb_endpoint_xfer_isoc(dep->endpoint.desc))
			mult = 3;

		/*
		 * REVISIT: the following assumes we will always have enough
		 * space available on the FIFO RAM for all possible use cases.
		 * Make sure that's true somehow and change FIFO allocation
		 * accordingly.
		 *
		 * If we have Bulk or Isochronous endpoints, we want
		 * them to be able to be very, very fast. So we're giving
		 * those endpoints a fifo_size which is enough for 3 full
		 * packets
		 */
		tmp = mult * (dep->endpoint.maxpacket + mdwidth);
		tmp += mdwidth;

		fifo_size = DIV_ROUND_UP(tmp, mdwidth);

		fifo_size |= (last_fifo_depth << 16);

		dwc3_trace(trace_dwc3_gadget, "%s: Fifo Addr %04x Size %d",
				dep->name, last_fifo_depth, fifo_size & 0xffff);

		dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(num), fifo_size);

		last_fifo_depth += (fifo_size & 0xffff);
	}

	return 0;
}

void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
		int status)
{
	struct dwc3			*dwc = dep->dwc;
	unsigned int			unmap_after_complete = false;
	int				i;

	if (req->queued) {
		i = 0;
		do {
			dep->busy_slot++;
			/*
			 * Skip LINK TRB. We can't use req->trb and check for
			 * DWC3_TRBCTL_LINK_TRB because it points the TRB we
			 * just completed (not the LINK TRB).
			 */
			if (((dep->busy_slot & DWC3_TRB_MASK) ==
				DWC3_TRB_NUM- 1) &&
				usb_endpoint_xfer_isoc(dep->endpoint.desc))
				dep->busy_slot++;
		} while(++i < req->request.num_mapped_sgs);
		req->queued = false;
	}
	/* Only delete from the list if the item isn't poisoned. */
	if (req->list.next != LIST_POISON1)
		list_del(&req->list);
	req->trb = NULL;

	if (req->request.status == -EINPROGRESS)
		req->request.status = status;

	/*
	 * NOTICE we don't want to unmap before calling ->complete() if we're
	 * dealing with a bounced ep0 request. If we unmap it here, we would end
	 * up overwritting the contents of req->buf and this could confuse the
	 * gadget driver.
	 */
	if (dwc->ep0_bounced && dep->number <= 1) {
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
		if (req->request.length > DWC3_EP0_BOUNCE_SIZE)
		{
			// we need unmap requst.
			usb_gadget_unmap_request(&dwc->gadget, &req->request,
					req->direction);
		}
#endif
		dwc->ep0_bounced = false;
		unmap_after_complete = true;
	} else {
		usb_gadget_unmap_request(&dwc->gadget,
				&req->request, req->direction);
	}

	dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n",
			req, dep->name, req->request.actual,
			req->request.length, status);
	trace_dwc3_gadget_giveback(req);

	spin_unlock(&dwc->lock);
	usb_gadget_giveback_request(&dep->endpoint, &req->request);
	spin_lock(&dwc->lock);

	if (unmap_after_complete)
		usb_gadget_unmap_request(&dwc->gadget,
				&req->request, req->direction);
}

int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
{
	u32		timeout = 500;
	u32		reg;

	trace_dwc3_gadget_generic_cmd(cmd, param);

	dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
	dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);

	do {
		reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
		if (!(reg & DWC3_DGCMD_CMDACT)) {
			dwc3_trace(trace_dwc3_gadget,
					"Command Complete --> %d",
					DWC3_DGCMD_STATUS(reg));
			if (DWC3_DGCMD_STATUS(reg))
				return -EINVAL;
			return 0;
		}

		/*
		 * We can't sleep here, because it's also called from
		 * interrupt context.
		 */
		timeout--;
		if (!timeout) {
			dwc3_trace(trace_dwc3_gadget,
					"Command Timed Out");
			return -ETIMEDOUT;
		}
		udelay(1);
	} while (1);
}

int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
		unsigned cmd, struct dwc3_gadget_ep_cmd_params *params)
{
	struct dwc3_ep		*dep = dwc->eps[ep];
	u32			timeout = 500;
	u32			reg;

	trace_dwc3_gadget_ep_cmd(dep, cmd, params);

	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0);
	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR1(ep), params->param1);
	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR2(ep), params->param2);

	dwc3_writel(dwc->regs, DWC3_DEPCMD(ep), cmd | DWC3_DEPCMD_CMDACT);
	do {
		reg = dwc3_readl(dwc->regs, DWC3_DEPCMD(ep));
		if (!(reg & DWC3_DEPCMD_CMDACT)) {
			dwc3_trace(trace_dwc3_gadget,
					"Command Complete --> %d",
					DWC3_DEPCMD_STATUS(reg));
			if (DWC3_DEPCMD_STATUS(reg) & ~DEPEVT_TRANSFER_BUS_EXPIRY)
				return -EINVAL;
			return 0;
		}

		/*
		 * We can't sleep here, because it is also called from
		 * interrupt context.
		 */
		timeout--;
		if (!timeout) {
			dwc3_trace(trace_dwc3_gadget,
					"Command Timed Out");
			return -ETIMEDOUT;
		}

		udelay(1);
	} while (1);
}

static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
		struct dwc3_trb *trb)
{
	u32		offset = (char *) trb - (char *) dep->trb_pool;

	return dep->trb_pool_dma + offset;
}

static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
{
	struct dwc3		*dwc = dep->dwc;

	if (dep->trb_pool)
		return 0;

	dep->trb_pool = dma_alloc_coherent(dwc->dev,
			sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
			&dep->trb_pool_dma, GFP_KERNEL);
	if (!dep->trb_pool) {
		dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
				dep->name);
		return -ENOMEM;
	}

	return 0;
}

static void dwc3_free_trb_pool(struct dwc3_ep *dep)
{
	struct dwc3		*dwc = dep->dwc;

	dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
			dep->trb_pool, dep->trb_pool_dma);

	dep->trb_pool = NULL;
	dep->trb_pool_dma = 0;
}

static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);

/**
 * dwc3_gadget_start_config - Configure EP resources
 * @dwc: pointer to our controller context structure
 * @dep: endpoint that is being enabled
 *
 * The assignment of transfer resources cannot perfectly follow the
 * data book due to the fact that the controller driver does not have
 * all knowledge of the configuration in advance. It is given this
 * information piecemeal by the composite gadget framework after every
 * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
 * programming model in this scenario can cause errors. For two
 * reasons:
 *
 * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
 * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
 * multiple interfaces.
 *
 * 2) The databook does not mention doing more DEPXFERCFG for new
 * endpoint on alt setting (8.1.6).
 *
 * The following simplified method is used instead:
 *
 * All hardware endpoints can be assigned a transfer resource and this
 * setting will stay persistent until either a core reset or
 * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
 * do DEPXFERCFG for every hardware endpoint as well. We are
 * guaranteed that there are as many transfer resources as endpoints.
 *
 * This function is called for each endpoint when it is being enabled
 * but is triggered only when called for EP0-out, which always happens
 * first, and which should only happen in one of the above conditions.
 */
static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
{
	struct dwc3_gadget_ep_cmd_params params;
	u32			cmd;
	int			i;
	int			ret;

	if (dep->number)
		return 0;

	memset(&params, 0x00, sizeof(params));
	cmd = DWC3_DEPCMD_DEPSTARTCFG;

	ret = dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
	if (ret)
		return ret;

	for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
		struct dwc3_ep *dep = dwc->eps[i];

		if (!dep)
			continue;

		ret = dwc3_gadget_set_xfer_resource(dwc, dep);
		if (ret)
			return ret;
	}

	return 0;
}

static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
		const struct usb_endpoint_descriptor *desc,
		const struct usb_ss_ep_comp_descriptor *comp_desc,
		bool ignore, bool restore)
{
	struct dwc3_gadget_ep_cmd_params params;

	memset(&params, 0x00, sizeof(params));

	params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
		| DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));

	/* Burst size is only needed in SuperSpeed mode */
	if (dwc->gadget.speed == USB_SPEED_SUPER) {
		u32 burst = dep->endpoint.maxburst - 1;

		params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst);
	}

	if (ignore)
		params.param0 |= DWC3_DEPCFG_IGN_SEQ_NUM;

	if (restore) {
		params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
		params.param2 |= dep->saved_state;
	}

	params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN
		| DWC3_DEPCFG_XFER_NOT_READY_EN;

	if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
		params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
			| DWC3_DEPCFG_STREAM_EVENT_EN;
		dep->stream_capable = true;
	}

	if (!usb_endpoint_xfer_control(desc))
		params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;

	/*
	 * We are doing 1:1 mapping for endpoints, meaning
	 * Physical Endpoints 2 maps to Logical Endpoint 2 and
	 * so on. We consider the direction bit as part of the physical
	 * endpoint number. So USB endpoint 0x81 is 0x03.
	 */
	params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);

	/*
	 * We must use the lower 16 TX FIFOs even though
	 * HW might have more
	 */
	if (dep->direction)
		params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);

	if (desc->bInterval) {
		params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
		dep->interval = 1 << (desc->bInterval - 1);
	}

	return dwc3_send_gadget_ep_cmd(dwc, dep->number,
			DWC3_DEPCMD_SETEPCONFIG, &params);
}

static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
{
	struct dwc3_gadget_ep_cmd_params params;

	memset(&params, 0x00, sizeof(params));

	params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);

	return dwc3_send_gadget_ep_cmd(dwc, dep->number,
			DWC3_DEPCMD_SETTRANSFRESOURCE, &params);
}

/**
 * __dwc3_gadget_ep_enable - Initializes a HW endpoint
 * @dep: endpoint to be initialized
 * @desc: USB Endpoint Descriptor
 *
 * Caller should take care of locking
 */
static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
		const struct usb_endpoint_descriptor *desc,
		const struct usb_ss_ep_comp_descriptor *comp_desc,
		bool ignore, bool restore)
{
	struct dwc3		*dwc = dep->dwc;
	u32			reg;
	int			ret;

	dwc3_trace(trace_dwc3_gadget, "Enabling %s", dep->name);

	if (!(dep->flags & DWC3_EP_ENABLED)) {
		ret = dwc3_gadget_start_config(dwc, dep);
		if (ret)
			return ret;
	}

	ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, ignore,
			restore);
	if (ret)
		return ret;

	if (!(dep->flags & DWC3_EP_ENABLED)) {
		struct dwc3_trb	*trb_st_hw;
		struct dwc3_trb	*trb_link;

		dep->endpoint.desc = desc;
		dep->comp_desc = comp_desc;
		dep->type = usb_endpoint_type(desc);
		dep->flags |= DWC3_EP_ENABLED;

		reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
		reg |= DWC3_DALEPENA_EP(dep->number);
		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);

		if (!usb_endpoint_xfer_isoc(desc))
			return 0;

		/* Link TRB for ISOC. The HWO bit is never reset */
		trb_st_hw = &dep->trb_pool[0];

		trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
		memset(trb_link, 0, sizeof(*trb_link));

		trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
		trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
		trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
		trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
	}

	switch (usb_endpoint_type(desc)) {
	case USB_ENDPOINT_XFER_CONTROL:
		strlcat(dep->name, "-control", sizeof(dep->name));
		break;
	case USB_ENDPOINT_XFER_ISOC:
		strlcat(dep->name, "-isoc", sizeof(dep->name));
		break;
	case USB_ENDPOINT_XFER_BULK:
		strlcat(dep->name, "-bulk", sizeof(dep->name));
		break;
	case USB_ENDPOINT_XFER_INT:
		strlcat(dep->name, "-int", sizeof(dep->name));
		break;
	default:
		dev_err(dwc->dev, "invalid endpoint transfer type\n");
	}

	return 0;
}

static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force);
static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
{
	struct dwc3_request		*req;

	if (!list_empty(&dep->req_queued)) {
		dwc3_stop_active_transfer(dwc, dep->number, true);

		/* - giveback all requests to gadget driver */
		while (!list_empty(&dep->req_queued)) {
			req = next_request(&dep->req_queued);

			dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
		}
	}

	while (!list_empty(&dep->request_list)) {
		req = next_request(&dep->request_list);

		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
	}
}

/**
 * __dwc3_gadget_ep_disable - Disables a HW endpoint
 * @dep: the endpoint to disable
 *
 * This function also removes requests which are currently processed ny the
 * hardware and those which are not yet scheduled.
 * Caller should take care of locking.
 */
static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
{
	struct dwc3		*dwc = dep->dwc;
	u32			reg;

	dwc3_trace(trace_dwc3_gadget, "Disabling %s", dep->name);

	dwc3_remove_requests(dwc, dep);

	/* make sure HW endpoint isn't stalled */
	if (dep->flags & DWC3_EP_STALL)
		__dwc3_gadget_ep_set_halt(dep, 0, false);

	reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
	reg &= ~DWC3_DALEPENA_EP(dep->number);
	dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);

	dep->flags = 0;
	dep->stream_capable = false;
	dep->endpoint.desc = NULL;
	dep->comp_desc = NULL;
	dep->type = 0;

	snprintf(dep->name, sizeof(dep->name), "ep%d%s",
			dep->number >> 1,
			(dep->number & 1) ? "in" : "out");

	return 0;
}

/* -------------------------------------------------------------------------- */

static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
		const struct usb_endpoint_descriptor *desc)
{
	return -EINVAL;
}

static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
{
	return -EINVAL;
}

/* -------------------------------------------------------------------------- */

static int dwc3_gadget_ep_enable(struct usb_ep *ep,
		const struct usb_endpoint_descriptor *desc)
{
	struct dwc3_ep			*dep;
	struct dwc3			*dwc;
	unsigned long			flags;
	int				ret;

	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
		pr_debug("dwc3: invalid parameters\n");
		return -EINVAL;
	}

	if (!desc->wMaxPacketSize) {
		pr_debug("dwc3: missing wMaxPacketSize\n");
		return -EINVAL;
	}

	dep = to_dwc3_ep(ep);
	dwc = dep->dwc;

	if (dep->flags & DWC3_EP_ENABLED) {
		dev_WARN_ONCE(dwc->dev, true, "%s is already enabled\n",
				dep->name);
		return 0;
	}

	spin_lock_irqsave(&dwc->lock, flags);
	ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false, false);
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static int dwc3_gadget_ep_disable(struct usb_ep *ep)
{
	struct dwc3_ep			*dep;
	struct dwc3			*dwc;
	unsigned long			flags;
	int				ret;

	if (!ep) {
		pr_debug("dwc3: invalid parameters\n");
		return -EINVAL;
	}

	dep = to_dwc3_ep(ep);
	dwc = dep->dwc;

	if (!(dep->flags & DWC3_EP_ENABLED)) {
		dev_WARN_ONCE(dwc->dev, true, "%s is already disabled\n",
				dep->name);
		return 0;
	}

	spin_lock_irqsave(&dwc->lock, flags);
	ret = __dwc3_gadget_ep_disable(dep);
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
	gfp_t gfp_flags)
{
	struct dwc3_request		*req;
	struct dwc3_ep			*dep = to_dwc3_ep(ep);

	req = kzalloc(sizeof(*req), gfp_flags);
	if (!req)
		return NULL;

	req->epnum	= dep->number;
	req->dep	= dep;

	trace_dwc3_alloc_request(req);

	return &req->request;
}

static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
		struct usb_request *request)
{
	struct dwc3_request		*req = to_dwc3_request(request);

	trace_dwc3_free_request(req);
	kfree(req);
}

/**
 * dwc3_prepare_one_trb - setup one TRB from one request
 * @dep: endpoint for which this request is prepared
 * @req: dwc3_request pointer
 */
static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
		struct dwc3_request *req, dma_addr_t dma,
		unsigned length, unsigned last, unsigned chain, unsigned node)
{
	struct dwc3_trb		*trb;

	dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
			dep->name, req, (unsigned long long) dma,
			length, last ? " last" : "",
			chain ? " chain" : "");

	trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];

	if (!req->trb) {
		dwc3_gadget_move_request_queued(req);
		req->trb = trb;
		req->trb_dma = dwc3_trb_dma_offset(dep, trb);
		req->start_slot = dep->free_slot & DWC3_TRB_MASK;
	}

	dep->free_slot++;
	/* Skip the LINK-TRB on ISOC */
	if (((dep->free_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
			usb_endpoint_xfer_isoc(dep->endpoint.desc))
		dep->free_slot++;

	trb->size = DWC3_TRB_SIZE_LENGTH(length);
	trb->bpl = lower_32_bits(dma);
	trb->bph = upper_32_bits(dma);

	switch (usb_endpoint_type(dep->endpoint.desc)) {
	case USB_ENDPOINT_XFER_CONTROL:
		trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
		break;

	case USB_ENDPOINT_XFER_ISOC:
		if (!node)
			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
		else
			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
		break;

	case USB_ENDPOINT_XFER_BULK:
	case USB_ENDPOINT_XFER_INT:
		trb->ctrl = DWC3_TRBCTL_NORMAL;
		break;
	default:
		/*
		 * This is only possible with faulty memory because we
		 * checked it already :)
		 */
		BUG();
	}

	if (!req->request.no_interrupt && !chain)
		trb->ctrl |= DWC3_TRB_CTRL_IOC;

	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
		trb->ctrl |= DWC3_TRB_CTRL_CSP;
	} else if (last) {
		trb->ctrl |= DWC3_TRB_CTRL_LST;
	}

	if (chain)
		trb->ctrl |= DWC3_TRB_CTRL_CHN;

	if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
		trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);

	trb->ctrl |= DWC3_TRB_CTRL_HWO;

	trace_dwc3_prepare_trb(dep, trb);
}

/*
 * dwc3_prepare_trbs - setup TRBs from requests
 * @dep: endpoint for which requests are being prepared
 * @starting: true if the endpoint is idle and no requests are queued.
 *
 * The function goes through the requests list and sets up TRBs for the
 * transfers. The function returns once there are no more TRBs available or
 * it runs out of requests.
 */
static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
{
	struct dwc3_request	*req, *n;
	u32			trbs_left;
	u32			max;
	unsigned int		last_one = 0;

	BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);

	/* the first request must not be queued */
	trbs_left = (dep->busy_slot - dep->free_slot) & DWC3_TRB_MASK;

	/* Can't wrap around on a non-isoc EP since there's no link TRB */
	if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
		max = DWC3_TRB_NUM - (dep->free_slot & DWC3_TRB_MASK);
		if (trbs_left > max)
			trbs_left = max;
	}

	/*
	 * If busy & slot are equal than it is either full or empty. If we are
	 * starting to process requests then we are empty. Otherwise we are
	 * full and don't do anything
	 */
	if (!trbs_left) {
		if (!starting)
			return;
		trbs_left = DWC3_TRB_NUM;
		/*
		 * In case we start from scratch, we queue the ISOC requests
		 * starting from slot 1. This is done because we use ring
		 * buffer and have no LST bit to stop us. Instead, we place
		 * IOC bit every TRB_NUM/4. We try to avoid having an interrupt
		 * after the first request so we start at slot 1 and have
		 * 7 requests proceed before we hit the first IOC.
		 * Other transfer types don't use the ring buffer and are
		 * processed from the first TRB until the last one. Since we
		 * don't wrap around we have to start at the beginning.
		 */
		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
			dep->busy_slot = 1;
			dep->free_slot = 1;
		} else {
			dep->busy_slot = 0;
			dep->free_slot = 0;
		}
	}

	/* The last TRB is a link TRB, not used for xfer */
	if ((trbs_left <= 1) && usb_endpoint_xfer_isoc(dep->endpoint.desc))
		return;

	list_for_each_entry_safe(req, n, &dep->request_list, list) {
		unsigned	length;
		dma_addr_t	dma;
		last_one = false;

		if (req->request.num_mapped_sgs > 0) {
			struct usb_request *request = &req->request;
			struct scatterlist *sg = request->sg;
			struct scatterlist *s;
			int		i;

			for_each_sg(sg, s, request->num_mapped_sgs, i) {
				unsigned chain = true;

				length = sg_dma_len(s);
				dma = sg_dma_address(s);

				if (i == (request->num_mapped_sgs - 1) ||
						sg_is_last(s)) {
					if (list_empty(&dep->request_list))
						last_one = true;
					chain = false;
				}

				trbs_left--;
				if (!trbs_left)
					last_one = true;

				if (last_one)
					chain = false;

				dwc3_prepare_one_trb(dep, req, dma, length,
						last_one, chain, i);

				if (last_one)
					break;
			}

			if (last_one)
				break;
		} else {
			dma = req->request.dma;
			length = req->request.length;
			trbs_left--;

			if (!trbs_left)
				last_one = 1;

			/* Is this the last request? */
			if (list_is_last(&req->list, &dep->request_list))
				last_one = 1;

			/*
			To improve USB Tethering speed.
			Last_one set on prepare trb has to set for ncm certification.
			But It occurs to decrease USB Tethering throughput.
			So, last_one set is on endpoint out state.
			*/
			if(usb_endpoint_dir_in(dep->endpoint.desc))
				dwc3_prepare_one_trb(dep, req, dma, length,
						last_one, false, 0);
			else
				dwc3_prepare_one_trb(dep, req, dma, length,
						1, false, 0);

			if (last_one)
				break;
		}
	}
}

static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
		int start_new)
{
	struct dwc3_gadget_ep_cmd_params params;
	struct dwc3_request		*req;
	struct dwc3			*dwc = dep->dwc;
	int				ret;
	u32				cmd;

	WARN_ON(!dwc->pullups_connected);

	if (start_new && (dep->flags & DWC3_EP_BUSY)) {
		dwc3_trace(trace_dwc3_gadget, "%s: endpoint busy", dep->name);
		return -EBUSY;
	}

	/*
	 * If we are getting here after a short-out-packet we don't enqueue any
	 * new requests as we try to set the IOC bit only on the last request.
	 */
	if (start_new) {
		if (list_empty(&dep->req_queued))
			dwc3_prepare_trbs(dep, start_new);

		/* req points to the first request which will be sent */
		req = next_request(&dep->req_queued);
	} else {
		dwc3_prepare_trbs(dep, start_new);

		/*
		 * req points to the first request where HWO changed from 0 to 1
		 */
		req = next_request(&dep->req_queued);
	}
	if (!req) {
		dep->flags |= DWC3_EP_PENDING_REQUEST;
		return 0;
	}

	memset(&params, 0, sizeof(params));
	params.param0 = upper_32_bits(req->trb_dma);
	params.param1 = lower_32_bits(req->trb_dma);

	if (start_new) {
		cmd = DWC3_DEPCMD_STARTTRANSFER;
		if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
			cmd |= DWC3_DEPCMD_CMDIOC;
	} else {
		cmd = DWC3_DEPCMD_UPDATETRANSFER;
	}

	cmd |= DWC3_DEPCMD_PARAM(cmd_param);
	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
	if (ret < 0) {
		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");

		/*
		 * FIXME we need to iterate over the list of requests
		 * here and stop, unmap, free and del each of the linked
		 * requests instead of what we do now.
		 */
		usb_gadget_unmap_request(&dwc->gadget, &req->request,
				req->direction);
		list_del(&req->list);
		return ret;
	}

	dep->flags |= DWC3_EP_BUSY;

	if (start_new) {
		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
				dep->number);
		WARN_ON_ONCE(!dep->resource_index);
	}

	return 0;
}

static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
		struct dwc3_ep *dep, u32 cur_uf)
{
	u32 uf;

	dep->current_uf = cur_uf;
	if (list_empty(&dep->request_list)) {
		dwc3_trace(trace_dwc3_gadget,
				"ISOC ep %s run out for requests",
				dep->name);
		dep->flags |= DWC3_EP_PENDING_REQUEST;
		return;
	}

	/* 4 micro frames in the future */
	uf = cur_uf + dep->interval * 4;

	__dwc3_gadget_kick_transfer(dep, uf, 1);
}

static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
{
	u32 cur_uf, mask;

	mask = ~(dep->interval - 1);
	cur_uf = event->parameters & mask;

	__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
}

static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
{
	struct dwc3		*dwc = dep->dwc;
	int			ret;

	req->request.actual	= 0;
	req->request.status	= -EINPROGRESS;
	req->direction		= dep->direction;
	req->epnum		= dep->number;

	trace_dwc3_ep_queue(req);

	/*
	 * We only add to our list of requests now and
	 * start consuming the list once we get XferNotReady
	 * IRQ.
	 *
	 * That way, we avoid doing anything that we don't need
	 * to do now and defer it until the point we receive a
	 * particular token from the Host side.
	 *
	 * This will also avoid Host cancelling URBs due to too
	 * many NAKs.
	 */
	ret = usb_gadget_map_request(&dwc->gadget, &req->request,
			dep->direction);
	if (ret)
		return ret;

	list_add_tail(&req->list, &dep->request_list);

	/* prevent starting transfer if controller is stopped */
	if (!dwc->pullups_connected) {
		dev_dbg(dwc->dev, "queue request while udc is stopped");
		return 0;
	}

	/*
	 * There are a few special cases:
	 *
	 * 1. XferNotReady with empty list of requests. We need to kick the
	 *    transfer here in that situation, otherwise we will be NAKing
	 *    forever. If we get XferNotReady before gadget driver has a
	 *    chance to queue a request, we will ACK the IRQ but won't be
	 *    able to receive the data until the next request is queued.
	 *    The following code is handling exactly that.
	 *
	 */
	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
		/*
		 * If xfernotready is already elapsed and it is a case
		 * of isoc transfer, then issue END TRANSFER, so that
		 * you can receive xfernotready again and can have
		 * notion of current microframe.
		 */
		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
			/* If xfernotready event is recieved before issuing
			 * START TRANSFER command, don't issue END TRANSFER.
			 * Rather start queueing the requests by issuing START
			 * TRANSFER command.
			 */
			if (list_empty(&dep->req_queued) && dep->resource_index)
				dwc3_stop_active_transfer(dwc,
							dep->number, true);
			else
				__dwc3_gadget_start_isoc(dwc,
							dep, dep->current_uf);
			dep->flags &= ~DWC3_EP_PENDING_REQUEST;
			return 0;
		}

		ret = __dwc3_gadget_kick_transfer(dep, 0, true);
		if (!ret)
			dep->flags &= ~DWC3_EP_PENDING_REQUEST;

		goto out;
	}

	/*
	 * 2. XferInProgress on Isoc EP with an active transfer. We need to
	 *    kick the transfer here after queuing a request, otherwise the
	 *    core may not see the modified TRB(s).
	 */
	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
			(dep->flags & DWC3_EP_BUSY) &&
			!(dep->flags & DWC3_EP_MISSED_ISOC)) {
		WARN_ON_ONCE(!dep->resource_index);
		ret = __dwc3_gadget_kick_transfer(dep, dep->resource_index,
				false);
		goto out;
	}

	/*
	 * 4. Stream Capable Bulk Endpoints. We need to start the transfer
	 * right away, otherwise host will not know we have streams to be
	 * handled.
	 */
	if (dep->stream_capable)
		ret = __dwc3_gadget_kick_transfer(dep, 0, true);

out:
	if (ret && ret != -EBUSY)
		dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
				dep->name);
	if (ret == -EBUSY)
		ret = 0;

	return ret;
}

static void __dwc3_gadget_ep_zlp_complete(struct usb_ep *ep,
		struct usb_request *request)
{
	dwc3_gadget_ep_free_request(ep, request);
}

static int __dwc3_gadget_ep_queue_zlp(struct dwc3 *dwc, struct dwc3_ep *dep)
{
	struct dwc3_request		*req;
	struct usb_request		*request;
	struct usb_ep			*ep = &dep->endpoint;

	dwc3_trace(trace_dwc3_gadget, "queueing ZLP\n");
	request = dwc3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
	if (!request)
		return -ENOMEM;

	request->length = 0;
	request->buf = dwc->zlp_buf;
	request->complete = __dwc3_gadget_ep_zlp_complete;

	req = to_dwc3_request(request);

	return __dwc3_gadget_ep_queue(dep, req);
}

static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
	gfp_t gfp_flags)
{
	struct dwc3_request		*req = to_dwc3_request(request);
	struct dwc3_ep			*dep = to_dwc3_ep(ep);
	struct dwc3			*dwc = dep->dwc;

	unsigned long			flags;

	int				ret;

	spin_lock_irqsave(&dwc->lock, flags);
	if (!dep->endpoint.desc) {
		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
				request, ep->name);
		ret = -ESHUTDOWN;
		goto out;
	}

	if (WARN(req->dep != dep, "request %pK belongs to '%s'\n",
				request, req->dep->name)) {
		ret = -EINVAL;
		goto out;
	}

	ret = __dwc3_gadget_ep_queue(dep, req);

	/*
	 * Okay, here's the thing, if gadget driver has requested for a ZLP by
	 * setting request->zero, instead of doing magic, we will just queue an
	 * extra usb_request ourselves so that it gets handled the same way as
	 * any other request.
	 */
	if (ret == 0 && request->zero && request->length &&
	    (request->length % ep->maxpacket == 0))
		ret = __dwc3_gadget_ep_queue_zlp(dwc, dep);

out:
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
		struct usb_request *request)
{
	struct dwc3_request		*req = to_dwc3_request(request);
	struct dwc3_request		*r = NULL;

	struct dwc3_ep			*dep = to_dwc3_ep(ep);
	struct dwc3			*dwc = dep->dwc;

	unsigned long			flags;
	int				ret = 0;

	trace_dwc3_ep_dequeue(req);

	spin_lock_irqsave(&dwc->lock, flags);

	list_for_each_entry(r, &dep->request_list, list) {
		if (r == req)
			break;
	}

	if (r != req) {
		list_for_each_entry(r, &dep->req_queued, list) {
			if (r == req)
				break;
		}
		if (r == req) {
			/* wait until it is processed */
			dwc3_stop_active_transfer(dwc, dep->number, true);
			goto out1;
		}
		dev_err(dwc->dev, "request %pK was not queued to %s\n",
				request, ep->name);
		ret = -EINVAL;
		goto out0;
	}

out1:
	/* giveback the request */
	dwc3_gadget_giveback(dep, req, -ECONNRESET);

out0:
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
{
	struct dwc3_gadget_ep_cmd_params	params;
	struct dwc3				*dwc = dep->dwc;
	int					ret;

	if (dep->endpoint.desc == NULL)
		return -EINVAL;

	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
		return -EINVAL;
	}

	memset(&params, 0x00, sizeof(params));

	if (value) {
		if (!protocol && ((dep->direction && dep->flags & DWC3_EP_BUSY) ||
				(!list_empty(&dep->req_queued) ||
				 !list_empty(&dep->request_list)))) {
			dev_dbg(dwc->dev, "%s: pending request, cannot halt\n",
					dep->name);
			return -EAGAIN;
		}

		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
			DWC3_DEPCMD_SETSTALL, &params);
		if (ret)
			dev_err(dwc->dev, "failed to set STALL on %s\n",
					dep->name);
		else
			dep->flags |= DWC3_EP_STALL;
	} else {
		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
			DWC3_DEPCMD_CLEARSTALL, &params);
		if (ret)
			dev_err(dwc->dev, "failed to clear STALL on %s\n",
					dep->name);
		else
			dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
	}

	return ret;
}

static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
{
	struct dwc3_ep			*dep = to_dwc3_ep(ep);
	struct dwc3			*dwc = dep->dwc;

	unsigned long			flags;

	int				ret;

	spin_lock_irqsave(&dwc->lock, flags);
	ret = __dwc3_gadget_ep_set_halt(dep, value, false);
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
{
	struct dwc3_ep			*dep = to_dwc3_ep(ep);
	struct dwc3			*dwc = dep->dwc;
	unsigned long			flags;
	int				ret;

	spin_lock_irqsave(&dwc->lock, flags);
	dep->flags |= DWC3_EP_WEDGE;

	if (dep->number == 0 || dep->number == 1)
		ret = __dwc3_gadget_ep0_set_halt(ep, 1);
	else
		ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

/* -------------------------------------------------------------------------- */

static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
	.bLength	= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,
	.bmAttributes	= USB_ENDPOINT_XFER_CONTROL,
};

static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
	.enable		= dwc3_gadget_ep0_enable,
	.disable	= dwc3_gadget_ep0_disable,
	.alloc_request	= dwc3_gadget_ep_alloc_request,
	.free_request	= dwc3_gadget_ep_free_request,
	.queue		= dwc3_gadget_ep0_queue,
	.dequeue	= dwc3_gadget_ep_dequeue,
	.set_halt	= dwc3_gadget_ep0_set_halt,
	.set_wedge	= dwc3_gadget_ep_set_wedge,
};

static const struct usb_ep_ops dwc3_gadget_ep_ops = {
	.enable		= dwc3_gadget_ep_enable,
	.disable	= dwc3_gadget_ep_disable,
	.alloc_request	= dwc3_gadget_ep_alloc_request,
	.free_request	= dwc3_gadget_ep_free_request,
	.queue		= dwc3_gadget_ep_queue,
	.dequeue	= dwc3_gadget_ep_dequeue,
	.set_halt	= dwc3_gadget_ep_set_halt,
	.set_wedge	= dwc3_gadget_ep_set_wedge,
};

/* -------------------------------------------------------------------------- */

static int dwc3_gadget_get_frame(struct usb_gadget *g)
{
	struct dwc3		*dwc = gadget_to_dwc(g);
	u32			reg;

	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
	return DWC3_DSTS_SOFFN(reg);
}

static int dwc3_gadget_wakeup(struct usb_gadget *g)
{
	struct dwc3		*dwc = gadget_to_dwc(g);

	unsigned long		timeout;
	unsigned long		flags;

	u32			reg;

	int			ret = 0;

	u8			link_state;
	u8			speed;

	spin_lock_irqsave(&dwc->lock, flags);

	/*
	 * According to the Databook Remote wakeup request should
	 * be issued only when the device is in early suspend state.
	 *
	 * We can check that via USB Link State bits in DSTS register.
	 */
	reg = dwc3_readl(dwc->regs, DWC3_DSTS);

	speed = reg & DWC3_DSTS_CONNECTSPD;
	if (speed == DWC3_DSTS_SUPERSPEED) {
		dev_dbg(dwc->dev, "no wakeup on SuperSpeed\n");
		ret = -EINVAL;
		goto out;
	}

	link_state = DWC3_DSTS_USBLNKST(reg);

	switch (link_state) {
	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
		break;
	default:
		dev_dbg(dwc->dev, "can't wakeup from link state %d\n",
				link_state);
		ret = -EINVAL;
		goto out;
	}

	ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
	if (ret < 0) {
		dev_err(dwc->dev, "failed to put link in Recovery\n");
		goto out;
	}

	/* Recent versions do this automatically */
	if (dwc->revision < DWC3_REVISION_194A) {
		/* write zeroes to Link Change Request */
		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
		reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
	}

	/* poll until Link State changes to ON */
	timeout = jiffies + msecs_to_jiffies(100);

	while (!time_after(jiffies, timeout)) {
		reg = dwc3_readl(dwc->regs, DWC3_DSTS);

		/* in HS, means ON */
		if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
			break;
	}

	if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
		dev_err(dwc->dev, "failed to send remote wakeup\n");
		ret = -EINVAL;
	}

out:
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
		int is_selfpowered)
{
	struct dwc3		*dwc = gadget_to_dwc(g);
	unsigned long		flags;

	spin_lock_irqsave(&dwc->lock, flags);
	g->is_selfpowered = !!is_selfpowered;
	spin_unlock_irqrestore(&dwc->lock, flags);

	return 0;
}

static int dwc3_udc_init(struct dwc3 *dwc)
{
	struct dwc3_ep		*dep;
	u32			reg;
	int			ret = 0;

	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
	reg &= ~(DWC3_DCFG_SPEED_MASK);

	/**
	 * WORKAROUND: DWC3 revision < 2.20a have an issue
	 * which would cause metastability state on Run/Stop
	 * bit if we try to force the IP to USB2-only mode.
	 *
	 * Because of that, we cannot configure the IP to any
	 * speed other than the SuperSpeed
	 *
	 * Refers to:
	 *
	 * STAR#9000525659: Clock Domain Crossing on DCTL in
	 * USB 2.0 Mode
	 */
	if (dwc->revision < DWC3_REVISION_220A) {
		reg |= DWC3_DCFG_SUPERSPEED;
	} else {
		switch (dwc->maximum_speed) {
		case USB_SPEED_LOW:
			reg |= DWC3_DSTS_LOWSPEED;
			break;
		case USB_SPEED_FULL:
			reg |= DWC3_DSTS_FULLSPEED1;
			break;
		case USB_SPEED_HIGH:
			reg |= DWC3_DSTS_HIGHSPEED;
			break;
		case USB_SPEED_SUPER:   /* FALLTHROUGH */
		case USB_SPEED_UNKNOWN: /* FALTHROUGH */
		default:
			reg |= DWC3_DSTS_SUPERSPEED;
		}
	}
	dwc3_writel(dwc->regs, DWC3_DCFG, reg);

	/* Start with SuperSpeed Default */
	dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);

	dep = dwc->eps[0];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
			false);
	if (ret) {
		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
		goto err0;
	}

	dep = dwc->eps[1];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
			false);
	if (ret) {
		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
		goto err1;
	}

	/* begin to receive SETUP packets */
	dwc->ep0state = EP0_SETUP_PHASE;
	dwc3_ep0_out_start(dwc);

	return 0;

err1:
	__dwc3_gadget_ep_disable(dwc->eps[0]);

err0:
	return ret;
}

static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
{
	u32			reg;

	/* Enable all but Start and End of Frame IRQs */
	reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
			DWC3_DEVTEN_EVNTOVERFLOWEN |
			DWC3_DEVTEN_CMDCMPLTEN |
			DWC3_DEVTEN_ERRTICERREN |
			DWC3_DEVTEN_WKUPEVTEN |
			DWC3_DEVTEN_ULSTCNGEN |
			DWC3_DEVTEN_CONNECTDONEEN |
			DWC3_DEVTEN_USBRSTEN |
			DWC3_DEVTEN_DISCONNEVTEN);

	dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
}

static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
{
	/* mask all interrupts */
	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
}

static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
{
	u32			reg;
	u32			timeout = 1000;
	int			retries = 1000;
	int			ret = 0;

	printk(KERN_DEBUG"usb: %s is_on:%d\n",__func__, is_on);

	if (is_on) {
		dwc3_event_buffers_setup(dwc);
		dwc3_link_status_check(dwc);
		ret = dwc3_udc_init(dwc);
		if (ret) {
			dev_err(dwc->dev, "failed to reinitialize udc\n");
			return ret;
		}

		dwc3_gadget_enable_irq(dwc);

		reg = dwc3_readl(dwc->regs, DWC3_DCTL);

		if (dwc->revision <= DWC3_REVISION_187A) {
			reg &= ~DWC3_DCTL_TRGTULST_MASK;
			reg |= DWC3_DCTL_TRGTULST_RX_DET;
		}

		if (dwc->revision >= DWC3_REVISION_194A)
			reg &= ~DWC3_DCTL_KEEP_CONNECT;

		reg |= DWC3_DCTL_RUN_STOP;

		if (dwc->has_hibernation)
			reg |= DWC3_DCTL_KEEP_CONNECT;

		dwc->pullups_connected = true;
	} else {
		dwc3_gadget_disable_irq(dwc);
		dwc3_event_buffers_cleanup(dwc);
		__dwc3_gadget_ep_disable(dwc->eps[1]);
		__dwc3_gadget_ep_disable(dwc->eps[0]);
		
		/* we need to clear ep0 delayed status flag */
		dwc->delayed_status = 0;

		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
		reg &= ~DWC3_DCTL_RUN_STOP;

		if (dwc->has_hibernation && !suspend)
			reg &= ~DWC3_DCTL_KEEP_CONNECT;

		dwc->pullups_connected = false;
	}

	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	do {
		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
		if (is_on) {
			if (!(reg & DWC3_DSTS_DEVCTRLHLT))
				break;
		} else {
			if (reg & DWC3_DSTS_DEVCTRLHLT)
				break;
		}
		timeout--;
		if (!timeout) {
			if(is_on) {
				reg = dwc3_readl(dwc->regs, DWC3_DCTL);
				reg |= DWC3_DCTL_CSFTRST;
				dwc3_writel(dwc->regs, DWC3_DCTL, reg);
				dev_err(dwc->dev, "gadget run/stop timeout, DCTL : 0x%x\n", reg);
				reg = dwc3_readl(dwc->regs, DWC3_DSTS);
				dev_err(dwc->dev, "gadget run/stop timeout, DSTS : 0x%x\n", reg);
				do {
					reg = dwc3_readl(dwc->regs, DWC3_DCTL);
					if (!(reg & DWC3_DCTL_CSFTRST)) {
						dev_info(dwc->dev, "gadget run/stop DCTL softreset, DCTL : 0x%x\n",
								reg);
						goto good;
					}
					udelay(1);

				} while (--retries);

				return -ETIMEDOUT;
			} else {
				/* Do nothing in DCTL stop timeout */
				dev_err(dwc->dev, "gadget DCTL stop timeout, DSTS: 0x%x\n", reg);
				goto good;
			}
		}
		udelay(1);
	} while (1);

good:
	dwc3_trace(trace_dwc3_gadget, "gadget %s data soft-%s",
			dwc->gadget_driver
			? dwc->gadget_driver->function : "no-function",
			is_on ? "connect" : "disconnect");

	return ret;
}

static int dwc3_gadget_vbus_session(struct usb_gadget *g, int is_active)
{
	struct dwc3 *dwc = gadget_to_dwc(g);
	unsigned long flags;
	int ret = 0;

	if (!dwc->dotg)
		return -EPERM;

	is_active = !!is_active;

	pr_info("usb: %s: is_active = %d, softconnect = %d\n",
			__func__, is_active, dwc->softconnect);

	spin_lock_irqsave(&dwc->lock, flags);

	/* Mark that the vbus was powered */
	dwc->vbus_session = is_active;

	/*
	 * Check if upper level usb_gadget_driver was already registerd with
	 * this udc controller driver (if dwc3_gadget_start was called)
	 */
	if (dwc->gadget_driver && dwc->softconnect) {
		if (dwc->vbus_session) {
			/*
			 * Both vbus was activated by otg and pullup was
			 * signaled by the gadget driver.
			 */
			ret = dwc3_gadget_run_stop(dwc, 1, false);

#ifdef CONFIG_USB_NOTIFY_PROC_LOG
			if (ret == 0 )
				store_usblog_notify(NOTIFY_USBSTATE,
							(void *)"USB_STATE=VBUS:EN:SUCCESS", NULL);
			else
				store_usblog_notify(NOTIFY_USBSTATE,
							(void *)"USB_STATE=VBUS:EN:FAIL", NULL);
#endif
		} else {
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
			dwc3_gadget_cable_connect(dwc,false);
			dwc->start_config_issued = false;
			dwc->gadget.speed = USB_SPEED_UNKNOWN;
			dwc->setup_packet_pending = false;
#endif

			ret = dwc3_gadget_run_stop(dwc, 0, false);
#ifdef CONFIG_USB_NOTIFY_PROC_LOG
			if (ret == 0 )
				store_usblog_notify(NOTIFY_USBSTATE,
							(void *)"USB_STATE=VBUS:DIS:SUCCESS", NULL);
			else
				store_usblog_notify(NOTIFY_USBSTATE,
							(void *)"USB_STATE=VBUS:DIS:FAIL", NULL);
#endif

#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
			dwc3_disconnect_gadget(dwc);
#endif
		}

		schedule_work(&dwc->pm_qos_work_fsys);
	}

	spin_unlock_irqrestore(&dwc->lock, flags);

	if (ret)
		dev_err(dwc->dev, "dwc3 gadget run/stop error:%d\n", ret);

	if (dwc->rst_err_noti) {
		dwc->event_state = RELEASE;
		dwc->rst_err_noti = false;
		schedule_delayed_work(&dwc->usb_event_work, msecs_to_jiffies(0));
	}
	dwc->rst_err_cnt = 0;
	acc_dev_status = 0;

	return 0;
}

static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
{
	struct dwc3		*dwc = gadget_to_dwc(g);
	unsigned long		flags;
	struct usb_otg		*otg = &(dwc->dotg->otg);
	int			ret;

	is_on = !!is_on;

	spin_lock_irqsave(&dwc->lock, flags);

	pr_info("usb: %s: pullup = %d, vbus = %d\n",
			__func__, is_on, dwc->vbus_session);
	if (is_on == dwc->softconnect) {
		dev_dbg(dwc->dev, "pullup is already %s\n",
				is_on ? "on" : "off");
		spin_unlock_irqrestore(&dwc->lock, flags);
		return 0;
	}

	dwc->softconnect = is_on;

	if (dwc->dotg && !dwc->vbus_session) {
		spin_unlock_irqrestore(&dwc->lock, flags);
		/* Need to wait for vbus_session(on) from otg driver */
		return 0;
	}

	if (is_on) {
		dwc3_soft_reset(dwc);

		phy_tune(dwc->usb2_generic_phy, otg->state);
		phy_tune(dwc->usb3_generic_phy, otg->state);

		/**
		 * In case there is not a resistance to detect VBUS,
		 * DP/DM controls by S/W are needed at this point.
		 */
		if (dwc->is_not_vbus_pad) {
			phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_DISABLE, NULL);
			phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_DISABLE, NULL);
		}
	}

	ret = dwc3_gadget_run_stop(dwc, is_on, false);
#ifdef CONFIG_USB_NOTIFY_PROC_LOG
	if (ret == 0)
	{
		if (is_on)
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=PULLUP:EN:SUCCESS", NULL);
		else
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=PULLUP:DIS:SUCCESS", NULL);
	}
	else
	{
		if (is_on)
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=PULLUP:EN:FAIL", NULL);
		else
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=PULLUP:DIS:FAIL", NULL);
	}
#endif
	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
#endif
#ifdef CONFIG_USBIRQ_BALANCING_LTE_HIGHTP
static int set_cpu_core_from_usb_irq(int enable)
{
	int err = 0;
	unsigned int irq = gadget_irq;
	cpumask_var_t new_value;

	if (!irq_can_set_affinity(irq))
		return -EIO;

	if (enable){
		err = irq_set_affinity(irq, cpumask_of(1));
	} else {

		if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
			return -ENOMEM;

		cpumask_setall(new_value);

		if (!cpumask_intersects(new_value, cpu_online_mask)) {
			err = irq_select_affinity_usr(irq, new_value);
		} else {
			err = irq_set_affinity(irq, new_value);
		}
		free_cpumask_var(new_value);
	}

	return err;
}


static int rndis_notify_callback(struct notifier_block *this,
				unsigned long event, void *ptr)
{
	struct net_device *dev = ptr;

	if (!net_eq(dev_net(dev), &init_net))
		return NOTIFY_DONE;

	if (!strncmp(dev->name, "rndis", 5)) {
		switch (event) {
		case NETDEV_UP:
			set_cpu_core_from_usb_irq(true);
			break;
		case NETDEV_DOWN:
			set_cpu_core_from_usb_irq(false);
			break;
		}
	}
	return NOTIFY_DONE;
}
#endif
static int dwc3_gadget_start(struct usb_gadget *g,
		struct usb_gadget_driver *driver)
{
	struct dwc3		*dwc = gadget_to_dwc(g);
	unsigned long		flags;
	int			ret = 0;
	int			irq;

	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
	ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
			IRQF_SHARED, "dwc3", dwc);
#else
	ret = devm_request_irq(dwc->dev, irq, dwc3_interrupt,
			IRQF_SHARED, "dwc3", dwc);
#endif
	if (ret) {
		dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
				irq, ret);
		goto err0;
	}

	spin_lock_irqsave(&dwc->lock, flags);

	if (dwc->gadget_driver) {
		dev_err(dwc->dev, "%s is already bound to %s\n",
				dwc->gadget.name,
				dwc->gadget_driver->driver.name);
		ret = -EBUSY;
		goto err1;
	}

	dwc->gadget_driver	= driver;

	spin_unlock_irqrestore(&dwc->lock, flags);

#ifdef CONFIG_USBIRQ_BALANCING_LTE_HIGHTP
	gadget_irq = irq;
	rndis_notifier.notifier_call = rndis_notify_callback;
	register_netdevice_notifier(&rndis_notifier);
#endif

#ifdef CONFIG_ARGOS
	if (!zalloc_cpumask_var(&affinity_cpu_mask, GFP_KERNEL))
		return -ENOMEM;
	if (!zalloc_cpumask_var(&default_cpu_mask, GFP_KERNEL))
		return -ENOMEM;

	cpumask_copy(default_cpu_mask, get_default_cpu_mask());
	cpumask_or(affinity_cpu_mask, affinity_cpu_mask, cpumask_of(3));
	argos_irq_affinity_setup_label(irq, "USB", affinity_cpu_mask, default_cpu_mask);
#endif

	return 0;

err1:
	spin_unlock_irqrestore(&dwc->lock, flags);

	free_irq(irq, dwc);

err0:
	return ret;
}

static int dwc3_gadget_stop(struct usb_gadget *g)
{
	struct dwc3		*dwc = gadget_to_dwc(g);
	unsigned long		flags;
	int			irq;

	spin_lock_irqsave(&dwc->lock, flags);

	dwc3_gadget_disable_irq(dwc);
	__dwc3_gadget_ep_disable(dwc->eps[1]);
	__dwc3_gadget_ep_disable(dwc->eps[0]);

	dwc->gadget_driver	= NULL;

	spin_unlock_irqrestore(&dwc->lock, flags);

	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
	free_irq(irq, dwc);
#ifdef CONFIG_USBIRQ_BALANCING_LTE_HIGHTP
	unregister_netdevice_notifier(&rndis_notifier);
#endif

	return 0;
}

static const struct usb_gadget_ops dwc3_gadget_ops = {
	.get_frame		= dwc3_gadget_get_frame,
	.wakeup			= dwc3_gadget_wakeup,
	.set_selfpowered	= dwc3_gadget_set_selfpowered,
	.vbus_session		= dwc3_gadget_vbus_session,
	.pullup			= dwc3_gadget_pullup,
	.udc_start		= dwc3_gadget_start,
	.udc_stop		= dwc3_gadget_stop,
};

/* -------------------------------------------------------------------------- */

static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
		u8 num, u32 direction)
{
	struct dwc3_ep			*dep;
	u8				i;

	for (i = 0; i < num; i++) {
		u8 epnum = (i << 1) | (!!direction);

		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
		if (!dep)
			return -ENOMEM;

		dep->dwc = dwc;
		dep->number = epnum;
		dep->direction = !!direction;
		dwc->eps[epnum] = dep;

		snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
				(epnum & 1) ? "in" : "out");

		dep->endpoint.name = dep->name;

		dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);

		if (epnum == 0 || epnum == 1) {
			usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
			dep->endpoint.maxburst = 1;
			dep->endpoint.ops = &dwc3_gadget_ep0_ops;
			if (!epnum)
				dwc->gadget.ep0 = &dep->endpoint;
		} else {
			int		ret;

			usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
			dep->endpoint.max_streams = 15;
			dep->endpoint.ops = &dwc3_gadget_ep_ops;
			list_add_tail(&dep->endpoint.ep_list,
					&dwc->gadget.ep_list);

			ret = dwc3_alloc_trb_pool(dep);
			if (ret)
				return ret;
		}

		if (epnum == 0 || epnum == 1) {
			dep->endpoint.caps.type_control = true;
		} else {
			dep->endpoint.caps.type_iso = true;
			dep->endpoint.caps.type_bulk = true;
			dep->endpoint.caps.type_int = true;
		}

		dep->endpoint.caps.dir_in = !!direction;
		dep->endpoint.caps.dir_out = !direction;

		INIT_LIST_HEAD(&dep->request_list);
		INIT_LIST_HEAD(&dep->req_queued);
	}

	return 0;
}

static int dwc3_gadget_init_endpoints(struct dwc3 *dwc)
{
	int				ret;

	INIT_LIST_HEAD(&dwc->gadget.ep_list);

	ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_out_eps, 0);
	if (ret < 0) {
		dwc3_trace(trace_dwc3_gadget,
				"failed to allocate OUT endpoints");
		return ret;
	}

	ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_in_eps, 1);
	if (ret < 0) {
		dwc3_trace(trace_dwc3_gadget,
				"failed to allocate IN endpoints");
		return ret;
	}

	return 0;
}

static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
{
	struct dwc3_ep			*dep;
	u8				epnum;

	for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
		dep = dwc->eps[epnum];
		if (!dep)
			continue;
		/*
		 * Physical endpoints 0 and 1 are special; they form the
		 * bi-directional USB endpoint 0.
		 *
		 * For those two physical endpoints, we don't allocate a TRB
		 * pool nor do we add them the endpoints list. Due to that, we
		 * shouldn't do these two operations otherwise we would end up
		 * with all sorts of bugs when removing dwc3.ko.
		 */
		if (epnum != 0 && epnum != 1) {
			dwc3_free_trb_pool(dep);
			list_del(&dep->endpoint.ep_list);
		}

		kfree(dep);
	}
}

/* -------------------------------------------------------------------------- */

static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
		struct dwc3_request *req, struct dwc3_trb *trb,
		const struct dwc3_event_depevt *event, int status)
{
	unsigned int		count;
	unsigned int		s_pkt = 0;
	unsigned int		trb_status;

	trace_dwc3_complete_trb(dep, trb);

	if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
		/*
		 * We continue despite the error. There is not much we
		 * can do. If we don't clean it up we loop forever. If
		 * we skip the TRB then it gets overwritten after a
		 * while since we use them in a ring buffer. A BUG()
		 * would help. Lets hope that if this occurs, someone
		 * fixes the root cause instead of looking away :)
		 */
		dev_err(dwc->dev, "%s's TRB (%pK) still owned by HW\n",
				dep->name, trb);
	count = trb->size & DWC3_TRB_SIZE_MASK;

	if (dep->direction) {
		if (count) {
			trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
			if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
				dev_vdbg(dwc->dev, "missed is interval %s\n",
						dep->name);
				/*
				 * If missed isoc occurred and there is
				 * no request queued then issue END
				 * TRANSFER, so that core generates
				 * next xfernotready and we will issue
				 * a fresh START TRANSFER.
				 * If there are still queued request
				 * then wait, do not issue either END
				 * or UPDATE TRANSFER, just attach next
				 * request in request_list during
				 * giveback.If any future queued request
				 * is successfully transferred then we
				 * will issue UPDATE TRANSFER for all
				 * request in the request_list.
				 */
				dep->flags |= DWC3_EP_MISSED_ISOC;
			} else {
				dev_err(dwc->dev, "incomplete IN transfer %s\n",
						dep->name);
				status = -ECONNRESET;
			}
		} else {
			dep->flags &= ~DWC3_EP_MISSED_ISOC;
		}
	} else {
		if (count && (event->status & DEPEVT_STATUS_SHORT))
			s_pkt = 1;
	}

	if (s_pkt)
		return 1;
	if ((event->status & DEPEVT_STATUS_LST) &&
			(trb->ctrl & (DWC3_TRB_CTRL_LST |
				DWC3_TRB_CTRL_HWO)))
		return 1;
	if ((event->status & DEPEVT_STATUS_IOC) &&
			(trb->ctrl & DWC3_TRB_CTRL_IOC))
		return 1;
	return 0;
}

static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
		const struct dwc3_event_depevt *event, int status)
{
	struct dwc3_request	*req;
	struct dwc3_trb		*trb;
	unsigned int		slot;
	unsigned int		i;
	int			count = 0;
	int			ret;

	do {
		req = next_request(&dep->req_queued);
		if (!req) {
			WARN_ON_ONCE(1);
			return 1;
		}
		i = 0;
		do {
			slot = req->start_slot + i;
			if ((slot == DWC3_TRB_NUM - 1) &&
				usb_endpoint_xfer_isoc(dep->endpoint.desc))
				slot++;
			slot %= DWC3_TRB_NUM;
			trb = &dep->trb_pool[slot];
			count += trb->size & DWC3_TRB_SIZE_MASK;


			ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
					event, status);
			if (ret)
				break;
		} while (++i < req->request.num_mapped_sgs);

		/*
		 * We assume here we will always receive the entire data block
		 * which we should receive. Meaning, if we program RX to
		 * receive 4K but we receive only 2K, we assume that's all we
		 * should receive and we simply bounce the request back to the
		 * gadget driver for further processing.
		 */
		req->request.actual += req->request.length - count;
		dwc3_gadget_giveback(dep, req, status);

		if (ret)
			break;
	} while (1);

	/*
	  * Our endpoint might get disabled by another thread during
	  * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
	  * early on so DWC3_EP_BUSY flag gets cleared
	  */
	if (!dep->endpoint.desc)
		return 1;

	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
			list_empty(&dep->req_queued)) {
		if (list_empty(&dep->request_list))
			/*
			 * If there is no entry in request list then do
			 * not issue END TRANSFER now. Just set PENDING
			 * flag, so that END TRANSFER is issued when an
			 * entry is added into request list.
			 */
			dep->flags |= DWC3_EP_PENDING_REQUEST;
		else
			dwc3_stop_active_transfer(dwc, dep->number, true);
		dep->flags &= ~DWC3_EP_MISSED_ISOC;
		return 1;
	}

	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
		if ((event->status & DEPEVT_STATUS_IOC) &&
				(trb->ctrl & DWC3_TRB_CTRL_IOC))
			return 0;
	return 1;
}

static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
{
	unsigned		status = 0;
	int			clean_busy;
	u32			is_xfer_complete;

	if (dep->endpoint.desc == NULL)
		return;

	is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);

	if (event->status & DEPEVT_STATUS_BUSERR)
		status = -ECONNRESET;

	clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
	if (clean_busy && (!dep->endpoint.desc || is_xfer_complete ||
				usb_endpoint_xfer_isoc(dep->endpoint.desc)))
		dep->flags &= ~DWC3_EP_BUSY;

	/*
	 * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
	 * See dwc3_gadget_linksts_change_interrupt() for 1st half.
	 */
	if (dwc->revision < DWC3_REVISION_183A) {
		u32		reg;
		int		i;

		for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
			dep = dwc->eps[i];

			if (!(dep->flags & DWC3_EP_ENABLED))
				continue;

			if (!list_empty(&dep->req_queued))
				return;
		}

		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
		reg |= dwc->u1u2;
		dwc3_writel(dwc->regs, DWC3_DCTL, reg);

		dwc->u1u2 = 0;
	}

	if (!dep->endpoint.desc)
		return;

	if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
		int ret;

		ret = __dwc3_gadget_kick_transfer(dep, 0, is_xfer_complete);
		if (!ret || ret == -EBUSY)
			return;
	}
}

static void dwc3_endpoint_command_complete(struct dwc3 *dwc,
		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
{
	u32			cmdtyp, temp;
	struct dwc3_request	*req1, *n;

	temp = *(u32 *)event;
	cmdtyp = (temp >> DWC3_DEPEVT_CmdTyp_SHIFT) &
		DWC3_DEPCMDx_CmdTyp_MASK;

	if (cmdtyp == DWC3_DEPCMD_STARTTRANSFER) {
		if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
				(temp & DWC3_DEPEVT_EventStatus_BusTimeExp)) {

			if (!dep->resource_index) {
				dep->resource_index =
					dwc3_gadget_ep_get_transfer_index(dwc,
							dep->number);
				WARN_ON_ONCE(!dep->resource_index);
			}

			dwc3_stop_active_transfer(dwc, dep->number, true);

			list_for_each_entry_safe_reverse(req1, n,
					&dep->req_queued, list) {

				req1->trb = NULL;
				dwc3_gadget_move_request_list_front(req1);

				if (req1->request.num_mapped_sgs)
					dep->busy_slot +=
						req1->request.num_mapped_sgs;
				else
					dep->busy_slot++;

				if ((dep->busy_slot & DWC3_TRB_MASK) ==
						DWC3_TRB_NUM - 1)
					dep->busy_slot++;
			}
		}
	}
}

static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
		const struct dwc3_event_depevt *event)
{
	struct dwc3_ep		*dep;
	u8			epnum = event->endpoint_number;

	dep = dwc->eps[epnum];

	if (!(dep->flags & DWC3_EP_ENABLED))
		return;

	if (epnum == 0 || epnum == 1) {
		dwc3_ep0_interrupt(dwc, event);
		return;
	}

	switch (event->endpoint_event) {
	case DWC3_DEPEVT_XFERCOMPLETE:
		dep->resource_index = 0;

		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
			dev_dbg(dwc->dev, "%s is an Isochronous endpoint\n",
					dep->name);
			return;
		}

		dwc3_endpoint_transfer_complete(dwc, dep, event);
		break;
	case DWC3_DEPEVT_XFERINPROGRESS:
		dwc3_endpoint_transfer_complete(dwc, dep, event);
		break;
	case DWC3_DEPEVT_XFERNOTREADY:
		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
			dwc3_gadget_start_isoc(dwc, dep, event);
		} else {
			int active;
			int ret;

			active = event->status & DEPEVT_STATUS_TRANSFER_ACTIVE;

			dwc3_trace(trace_dwc3_gadget, "%s: reason %s",
					dep->name, active ? "Transfer Active"
					: "Transfer Not Active");

			ret = __dwc3_gadget_kick_transfer(dep, 0, !active);
			if (!ret || ret == -EBUSY)
				return;

			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
					dep->name);
		}

		break;
	case DWC3_DEPEVT_STREAMEVT:
		if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
			dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
					dep->name);
			return;
		}

		switch (event->status) {
		case DEPEVT_STREAMEVT_FOUND:
			dwc3_trace(trace_dwc3_gadget,
					"Stream %d found and started",
					event->parameters);

			break;
		case DEPEVT_STREAMEVT_NOTFOUND:
			/* FALLTHROUGH */
		default:
			dev_dbg(dwc->dev, "Couldn't find suitable stream\n");
		}
		break;
	case DWC3_DEPEVT_RXTXFIFOEVT:
		dev_dbg(dwc->dev, "%s FIFO Overrun\n", dep->name);
		break;
	case DWC3_DEPEVT_EPCMDCMPLT:
		dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
		dwc3_endpoint_command_complete(dwc, dep, event);
		break;
	}
}

static void dwc3_disconnect_gadget(struct dwc3 *dwc)
{
	if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
		spin_unlock(&dwc->lock);
		dwc->gadget_driver->disconnect(&dwc->gadget);
		spin_lock(&dwc->lock);
	}
}

static void dwc3_suspend_gadget(struct dwc3 *dwc)
{
	if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
		spin_unlock(&dwc->lock);
		dwc->gadget_driver->suspend(&dwc->gadget);
		spin_lock(&dwc->lock);
	}
}

static void dwc3_resume_gadget(struct dwc3 *dwc)
{
	if (dwc->gadget_driver && dwc->gadget_driver->resume) {
		spin_unlock(&dwc->lock);
		dwc->gadget_driver->resume(&dwc->gadget);
		spin_lock(&dwc->lock);
	}
}

static void dwc3_reset_gadget(struct dwc3 *dwc)
{
	if (!dwc->gadget_driver)
		return;

	if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
		spin_unlock(&dwc->lock);
		usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
		spin_lock(&dwc->lock);
	}
}

static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
{
	struct dwc3_ep *dep;
	struct dwc3_gadget_ep_cmd_params params;
	u32 cmd;
	int ret;

	dep = dwc->eps[epnum];

	if (!dep->resource_index)
		return;

	/*
	 * NOTICE: We are violating what the Databook says about the
	 * EndTransfer command. Ideally we would _always_ wait for the
	 * EndTransfer Command Completion IRQ, but that's causing too
	 * much trouble synchronizing between us and gadget driver.
	 *
	 * We have discussed this with the IP Provider and it was
	 * suggested to giveback all requests here, but give HW some
	 * extra time to synchronize with the interconnect. We're using
	 * an arbitrary 100us delay for that.
	 *
	 * Note also that a similar handling was tested by Synopsys
	 * (thanks a lot Paul) and nothing bad has come out of it.
	 * In short, what we're doing is:
	 *
	 * - Issue EndTransfer WITH CMDIOC bit set
	 * - Wait 100us
	 */

	cmd = DWC3_DEPCMD_ENDTRANSFER;
	cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
	cmd |= DWC3_DEPCMD_CMDIOC;
	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
	memset(&params, 0, sizeof(params));
	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
	WARN_ON_ONCE(ret);
	dep->resource_index = 0;
	dep->flags &= ~DWC3_EP_BUSY;
	udelay(100);
}

static void dwc3_stop_active_transfers(struct dwc3 *dwc)
{
	u32 epnum;

	for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
		struct dwc3_ep *dep;

		dep = dwc->eps[epnum];
		if (!dep)
			continue;

		if (!(dep->flags & DWC3_EP_ENABLED))
			continue;

		dwc3_remove_requests(dwc, dep);
	}
}

static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
{
	u32 epnum;

	for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
		struct dwc3_ep *dep;
		struct dwc3_gadget_ep_cmd_params params;
		int ret;

		dep = dwc->eps[epnum];
		if (!dep)
			continue;

		if (!(dep->flags & DWC3_EP_STALL))
			continue;

		dep->flags &= ~DWC3_EP_STALL;

		memset(&params, 0, sizeof(params));
		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
				DWC3_DEPCMD_CLEARSTALL, &params);
		WARN_ON_ONCE(ret);
	}
}

static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
{
	int			reg;

	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
	reg &= ~DWC3_DCTL_INITU1ENA;
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	reg &= ~DWC3_DCTL_INITU2ENA;
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	dwc3_disconnect_gadget(dwc);

	dwc->gadget.speed = USB_SPEED_UNKNOWN;
	dwc->setup_packet_pending = false;
	usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);

	complete(&dwc->disconnect);
}

static void dwc3_gadget_usb_event_work(struct work_struct *work)
{
	struct dwc3 *dwc = container_of(work, struct dwc3, usb_event_work.work);

	pr_info("%s, event_state: %d\n", __func__, dwc->event_state);

	if (dwc->event_state)
		send_usb_err_uevent(USB_ERR_ABNORMAL_RESET, NOTIFY);
	else
		send_usb_err_uevent(USB_ERR_ABNORMAL_RESET, RELEASE);
}

static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
{
	u32			reg;
	ktime_t current_time;

	/*
	 * WORKAROUND: DWC3 revisions <1.88a have an issue which
	 * would cause a missing Disconnect Event if there's a
	 * pending Setup Packet in the FIFO.
	 *
	 * There's no suggested workaround on the official Bug
	 * report, which states that "unless the driver/application
	 * is doing any special handling of a disconnect event,
	 * there is no functional issue".
	 *
	 * Unfortunately, it turns out that we _do_ some special
	 * handling of a disconnect event, namely complete all
	 * pending transfers, notify gadget driver of the
	 * disconnection, and so on.
	 *
	 * Our suggested workaround is to follow the Disconnect
	 * Event steps here, instead, based on a setup_packet_pending
	 * flag. Such flag gets set whenever we have a XferNotReady
	 * event on EP0 and gets cleared on XferComplete for the
	 * same endpoint.
	 *
	 * Refers to:
	 *
	 * STAR#9000466709: RTL: Device : Disconnect event not
	 * generated if setup packet pending in FIFO
	 */
	if (dwc->revision < DWC3_REVISION_188A) {
		if (dwc->setup_packet_pending)
			dwc3_gadget_disconnect_interrupt(dwc);
	}
	/* after reset -> Default State */
	usb_gadget_set_state(&dwc->gadget, USB_STATE_DEFAULT);

	dwc->vbus_current= USB_CURRENT_UNCONFIGURED;
	schedule_work(&dwc->set_vbus_current_work);	

	dwc3_reset_gadget(dwc);

	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
	reg &= ~DWC3_DCTL_TSTCTRL_MASK;
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
	dwc->test_mode = false;

	dwc3_stop_active_transfers(dwc);
	dwc3_clear_stall_all_ep(dwc);

	/* Reset device address to zero */
	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
	dwc3_writel(dwc->regs, DWC3_DCFG, reg);

	if (acc_dev_status && (dwc->rst_err_noti == false)) {
		current_time.tv64 = ktime_to_ms(ktime_get_boottime());

		if ((dwc->rst_err_cnt == 0) && (dwc->gadget.state < USB_STATE_CONFIGURED)) {
			if ((current_time.tv64 - dwc->rst_time_before.tv64) < 1000) {
				dwc->rst_err_cnt++;
				dwc->rst_time_first.tv64 = dwc->rst_time_before.tv64;
			}
		} else {
			if ((current_time.tv64 - dwc->rst_time_first.tv64) < 1000) {
				dwc->rst_err_cnt++;
			} else {
				dwc->rst_err_cnt = 0;
			}
		}

		if (dwc->rst_err_cnt > ERR_RESET_CNT) {
			dwc->event_state = NOTIFY;
			schedule_delayed_work(&dwc->usb_event_work, msecs_to_jiffies(0));
			dwc->rst_err_noti = true;
		}

		pr_info("%s rst_err_cnt: %d, time_current: %lld, time_before: %lld\n",
			__func__, dwc->rst_err_cnt, current_time.tv64, dwc->rst_time_before.tv64);

		dwc->rst_time_before.tv64 = current_time.tv64;
	}

	if (dwc->is_not_vbus_pad) {
		phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_ENABLE, NULL);
		phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_ENABLE, NULL);
	}
}

static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
{
	u32 reg;

	reg = dwc3_readl(dwc->regs, DWC3_GCTL);
	reg |= DWC3_GCTL_RAMCLKSEL(DWC3_GCTL_CLK_MASK);
	dwc3_writel(dwc->regs, DWC3_GCTL, reg);
}

static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
{
	struct dwc3_ep		*dep;
	int			ret;
	u32			reg;
	u8			speed;

	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
	speed = reg & DWC3_DSTS_CONNECTSPD;
	dwc->speed = speed;

	switch (speed) {
	case DWC3_DCFG_SUPERSPEED:
		/*
		 * When the core is connected at USB 2.0 speeds, the ram_clk must
		 * attached to the bus clk.
		 * When the core is connected at USB 3.0 speed the ram_clk must
		 * attached to a source that is at least 125 MHz
		 */
		dwc3_update_ram_clk_sel(dwc, speed);

		/* update pm qos lock value for super speed*/
		schedule_work(&dwc->pm_qos_work_fsys);

		/*
		 * WORKAROUND: DWC3 revisions <1.90a have an issue which
		 * would cause a missing USB3 Reset event.
		 *
		 * In such situations, we should force a USB3 Reset
		 * event by calling our dwc3_gadget_reset_interrupt()
		 * routine.
		 *
		 * Refers to:
		 *
		 * STAR#9000483510: RTL: SS : USB3 reset event may
		 * not be generated always when the link enters poll
		 */
		if (dwc->revision < DWC3_REVISION_190A)
			dwc3_gadget_reset_interrupt(dwc);

		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
		dwc->gadget.ep0->maxpacket = 512;
		dwc->gadget.speed = USB_SPEED_SUPER;
		break;
	case DWC3_DCFG_HIGHSPEED:
		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
		dwc->gadget.ep0->maxpacket = 64;
		dwc->gadget.speed = USB_SPEED_HIGH;
		break;
	case DWC3_DCFG_FULLSPEED2:
	case DWC3_DCFG_FULLSPEED1:
		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
		dwc->gadget.ep0->maxpacket = 64;
		dwc->gadget.speed = USB_SPEED_FULL;
		break;
	case DWC3_DCFG_LOWSPEED:
		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
		dwc->gadget.ep0->maxpacket = 8;
		dwc->gadget.speed = USB_SPEED_LOW;
		break;
	}

	dwc->eps[1]->endpoint.maxpacket = dwc->gadget.ep0->maxpacket;

	/* Enable USB2 LPM Capability */

	if ((dwc->revision > DWC3_REVISION_194A)
			&& (speed != DWC3_DCFG_SUPERSPEED)) {
		reg = dwc3_readl(dwc->regs, DWC3_DCFG);
		reg |= DWC3_DCFG_LPM_CAP;
		dwc3_writel(dwc->regs, DWC3_DCFG, reg);

		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
		reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);

		reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);

		/*
		 * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
		 * DCFG.LPMCap is set, core responses with an ACK and the
		 * BESL value in the LPM token is less than or equal to LPM
		 * NYET threshold.
		 */
		WARN_ONCE(dwc->revision < DWC3_REVISION_240A
				&& dwc->has_lpm_erratum,
				"LPM Erratum not available on dwc3 revisisions < 2.40a\n");

		if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
			reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);

		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
	} else {
		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
		reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
	}

	dep = dwc->eps[0];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
			false);
	if (ret) {
		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
		return;
	}

	dep = dwc->eps[1];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
			false);
	if (ret) {
		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
		return;
	}

	printk(KERN_DEBUG"usb: %s speed:%s\n",__func__,		\
			(dwc->gadget.speed==USB_SPEED_SUPER)?"SS":	\
			(dwc->gadget.speed==USB_SPEED_HIGH)?"HS":	\
			(dwc->gadget.speed==USB_SPEED_FULL)?"FS":	\
			(dwc->gadget.speed==USB_SPEED_LOW)?"LS":"UNKNOWN");

	/*
	 * Configure PHY via GUSB3PIPECTLn if required.
	 *
	 * Update GTXFIFOSIZn
	 *
	 * In both cases reset values should be sufficient.
	 */

	/**
	 * In case there is not a resistance to detect VBUS,
	 * DP/DM controls by S/W are needed at this point.
	 */
	if (dwc->is_not_vbus_pad && !(speed & DWC3_DCFG_FULLSPEED1)) {
		phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_DISABLE, NULL);
		phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_DISABLE, NULL);
	}
}

static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
{
	if (dwc->is_not_vbus_pad) {
		phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_DISABLE, NULL);
		phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_DISABLE, NULL);
	}

	/*
	 * TODO take core out of low power mode when that's
	 * implemented.
	 */

	if (dwc->gadget_driver && dwc->gadget_driver->resume) {
		dwc->gadget_driver->resume(&dwc->gadget);
	}
}

static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
		unsigned int evtinfo)
{
	enum dwc3_link_state	next = evtinfo & DWC3_LINK_STATE_MASK;
	unsigned int		pwropt;

	/*
	 * WORKAROUND: DWC3 < 2.50a have an issue when configured without
	 * Hibernation mode enabled which would show up when device detects
	 * host-initiated U3 exit.
	 *
	 * In that case, device will generate a Link State Change Interrupt
	 * from U3 to RESUME which is only necessary if Hibernation is
	 * configured in.
	 *
	 * There are no functional changes due to such spurious event and we
	 * just need to ignore it.
	 *
	 * Refers to:
	 *
	 * STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
	 * operational mode
	 */
	pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
	if ((dwc->revision < DWC3_REVISION_250A) &&
			(pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
		if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
				(next == DWC3_LINK_STATE_RESUME)) {
			dwc3_trace(trace_dwc3_gadget,
					"ignoring transition U3 -> Resume");
			return;
		}
	}

	/*
	 * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
	 * on the link partner, the USB session might do multiple entry/exit
	 * of low power states before a transfer takes place.
	 *
	 * Due to this problem, we might experience lower throughput. The
	 * suggested workaround is to disable DCTL[12:9] bits if we're
	 * transitioning from U1/U2 to U0 and enable those bits again
	 * after a transfer completes and there are no pending transfers
	 * on any of the enabled endpoints.
	 *
	 * This is the first half of that workaround.
	 *
	 * Refers to:
	 *
	 * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
	 * core send LGO_Ux entering U0
	 */
	if (dwc->revision < DWC3_REVISION_183A) {
		if (next == DWC3_LINK_STATE_U0) {
			u32	u1u2;
			u32	reg;

			switch (dwc->link_state) {
			case DWC3_LINK_STATE_U1:
			case DWC3_LINK_STATE_U2:
				reg = dwc3_readl(dwc->regs, DWC3_DCTL);
				u1u2 = reg & (DWC3_DCTL_INITU2ENA
						| DWC3_DCTL_ACCEPTU2ENA
						| DWC3_DCTL_INITU1ENA
						| DWC3_DCTL_ACCEPTU1ENA);

				if (!dwc->u1u2)
					dwc->u1u2 = reg & u1u2;

				reg &= ~u1u2;

				dwc3_writel(dwc->regs, DWC3_DCTL, reg);
				break;
			default:
				/* do nothing */
				break;
			}
		}
	}

	switch (next) {
	case DWC3_LINK_STATE_U0:
		if (dwc->is_not_vbus_pad) {
			phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_ENABLE, NULL);
			phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_ENABLE, NULL);
		}
		break;
	case DWC3_LINK_STATE_U1:
		if (dwc->speed == USB_SPEED_SUPER)
			dwc3_suspend_gadget(dwc);
		break;
	case DWC3_LINK_STATE_U3:
		if (dwc->gadget.state == USB_STATE_CONFIGURED) {
#ifdef CONFIG_ENABLE_USB_SUSPEND_STATE
			dwc->vbus_current = USB_CURRENT_SUSPENDED;
#else
			dwc->vbus_current = USB_CURRENT_UNCONFIGURED;
#endif
			schedule_work(&dwc->set_vbus_current_work);
		}
	case DWC3_LINK_STATE_U2:
		dwc3_suspend_gadget(dwc);
		break;
	case DWC3_LINK_STATE_RX_DET:	/* Early Suspend in HS */
		if (dwc->is_not_vbus_pad) {
			phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_ENABLE, NULL);
			phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_ENABLE, NULL);
		}
		break;
	case DWC3_LINK_STATE_RESUME:
		if (dwc->is_not_vbus_pad) {
			phy_set(dwc->usb2_generic_phy, SET_DPPULLUP_ENABLE, NULL);
			phy_set(dwc->usb3_generic_phy, SET_DPPULLUP_ENABLE, NULL);
		}
		dwc3_resume_gadget(dwc);
		break;
	default:
		/* do nothing */
		break;
	}

	dwc->link_state = next;
}

static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
		unsigned int evtinfo)
{
	unsigned int is_ss = evtinfo & BIT(4);

	/**
	 * WORKAROUND: DWC3 revison 2.20a with hibernation support
	 * have a known issue which can cause USB CV TD.9.23 to fail
	 * randomly.
	 *
	 * Because of this issue, core could generate bogus hibernation
	 * events which SW needs to ignore.
	 *
	 * Refers to:
	 *
	 * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
	 * Device Fallback from SuperSpeed
	 */
	if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
		return;

	/* enter hibernation here */
}

static void dwc3_gadget_interrupt(struct dwc3 *dwc,
		const struct dwc3_event_devt *event)
{
	switch (event->type) {
	case DWC3_DEVICE_EVENT_DISCONNECT:
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
		dwc3_gadget_cable_connect(dwc,false);
#endif
		pr_info("usb: %s DISCONNECT\n", __func__);
		dwc3_gadget_disconnect_interrupt(dwc);
		break;
	case DWC3_DEVICE_EVENT_RESET:
		pr_info("usb: %s RESET\n", __func__);
		dwc3_gadget_reset_interrupt(dwc);
#ifdef CONFIG_USB_NOTIFY_PROC_LOG
		if (dwc->gadget.speed == USB_SPEED_FULL)
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=RESET:FULL", NULL);
		else if (dwc->gadget.speed == USB_SPEED_HIGH)
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=RESET:HIGH", NULL);		
		else if (dwc->gadget.speed == USB_SPEED_SUPER)
			store_usblog_notify(NOTIFY_USBSTATE,
						(void *)"USB_STATE=RESET:SUPER", NULL);
#endif
		break;
	case DWC3_DEVICE_EVENT_CONNECT_DONE:
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
		dwc3_gadget_cable_connect(dwc,true);
#endif
		dwc3_gadget_conndone_interrupt(dwc);
		break;
	case DWC3_DEVICE_EVENT_WAKEUP:
		dwc3_gadget_wakeup_interrupt(dwc);
		break;
	case DWC3_DEVICE_EVENT_HIBER_REQ:
		if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
					"unexpected hibernation event\n"))
			break;

		dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
		break;
	case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
		break;
	case DWC3_DEVICE_EVENT_EOPF:
		dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
		break;
	case DWC3_DEVICE_EVENT_SOF:
		dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
		break;
	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
		dwc3_trace(trace_dwc3_gadget, "Erratic Error");
		break;
	case DWC3_DEVICE_EVENT_CMD_CMPL:
		dwc3_trace(trace_dwc3_gadget, "Command Complete");
		break;
	case DWC3_DEVICE_EVENT_OVERFLOW:
		dwc3_trace(trace_dwc3_gadget, "Overflow");
		break;
	default:
		dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
	}
}

static void dwc3_process_event_entry(struct dwc3 *dwc,
		const union dwc3_event *event)
{
	trace_dwc3_event(event->raw);

	/* Endpoint IRQ, handle it and return early */
	if (event->type.is_devspec == 0) {
		/* depevt */
		return dwc3_endpoint_interrupt(dwc, &event->depevt);
	}

	switch (event->type.type) {
	case DWC3_EVENT_TYPE_DEV:
		dwc3_gadget_interrupt(dwc, &event->devt);
		break;
	/* REVISIT what to do with Carkit and I2C events ? */
	default:
		dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
	}
}

static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
{
	struct dwc3_event_buffer *evt;
	irqreturn_t ret = IRQ_NONE;
	int left;
	u32 reg;

	evt = dwc->ev_buffs[buf];
#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
	left = evt->count;

	if (!(evt->flags & DWC3_EVENT_PENDING))
		return IRQ_NONE;
#else
	reg = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(buf));
	reg &= DWC3_GEVNTCOUNT_MASK;
	evt->count = reg;
	left = evt->count;
#endif

	while (left > 0) {
		union dwc3_event event;

		event.raw = *(u32 *) (evt->buf + evt->lpos);

		dwc3_process_event_entry(dwc, &event);

		/*
		 * FIXME we wrap around correctly to the next entry as
		 * almost all entries are 4 bytes in size. There is one
		 * entry which has 12 bytes which is a regular entry
		 * followed by 8 bytes data. ATM I don't know how
		 * things are organized if we get next to the a
		 * boundary so I worry about that once we try to handle
		 * that.
		 */
		evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
		left -= 4;

		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(buf), 4);
	}

	evt->count = 0;
#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
	evt->flags &= ~DWC3_EVENT_PENDING;
#endif
	ret = IRQ_HANDLED;

#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
	/* Unmask interrupt */
	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(buf));
	reg &= ~DWC3_GEVNTSIZ_INTMASK;
	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(buf), reg);

#endif
	return ret;
}

#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc)
{
	struct dwc3 *dwc = _dwc;
	unsigned long flags;
	irqreturn_t ret = IRQ_NONE;
	int i;

	spin_lock_irqsave(&dwc->lock, flags);

	for (i = 0; i < dwc->num_event_buffers; i++)
		ret |= dwc3_process_event_buf(dwc, i);

	spin_unlock_irqrestore(&dwc->lock, flags);

	return ret;
}

static irqreturn_t dwc3_check_event_buf(struct dwc3 *dwc, u32 buf)
{
	struct dwc3_event_buffer *evt;
	u32 count;
	u32 reg;

	evt = dwc->ev_buffs[buf];

	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(buf));
	count &= DWC3_GEVNTCOUNT_MASK;
	if (!count)
		return IRQ_NONE;

	evt->count = count;
	evt->flags |= DWC3_EVENT_PENDING;

	/* Mask interrupt */
	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(buf));
	reg |= DWC3_GEVNTSIZ_INTMASK;
	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(buf), reg);

	return IRQ_WAKE_THREAD;
}
#endif

static irqreturn_t dwc3_interrupt(int irq, void *_dwc)
{
	struct dwc3			*dwc = _dwc;
	int				i;
	irqreturn_t			ret = IRQ_NONE;

	spin_lock(&dwc->lock);

	for (i = 0; i < dwc->num_event_buffers; i++) {
#if IS_ENABLED(DWC3_GADGET_IRQ_ORG)
		irqreturn_t status;

		status = dwc3_check_event_buf(dwc, i);
		if (status == IRQ_WAKE_THREAD)
			ret = status;
#else
		ret |= dwc3_process_event_buf(dwc, i);
#endif
	}

	spin_unlock(&dwc->lock);

	return ret;
}

/**
 * dwc3_gadget_init - Initializes gadget related registers
 * @dwc: pointer to our controller context structure
 *
 * Returns 0 on success otherwise negative errno.
 */
int dwc3_gadget_init(struct dwc3 *dwc)
{
	int					ret;

	dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
			&dwc->ctrl_req_addr, GFP_KERNEL);
	if (!dwc->ctrl_req) {
		dev_err(dwc->dev, "failed to allocate ctrl request\n");
		ret = -ENOMEM;
		goto err0;
	}

	INIT_DELAYED_WORK(&dwc->usb_event_work, dwc3_gadget_usb_event_work);

	dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
			&dwc->ep0_trb_addr, GFP_KERNEL);
	if (!dwc->ep0_trb) {
		dev_err(dwc->dev, "failed to allocate ep0 trb\n");
		ret = -ENOMEM;
		goto err1;
	}

	dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
	if (!dwc->setup_buf) {
		ret = -ENOMEM;
		goto err2;
	}

	dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
			DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
			GFP_KERNEL);
	if (!dwc->ep0_bounce) {
		dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
		ret = -ENOMEM;
		goto err3;
	}

	dwc->zlp_buf = kzalloc(DWC3_ZLP_BUF_SIZE, GFP_KERNEL);
	if (!dwc->zlp_buf) {
		ret = -ENOMEM;
		goto err4;
	}

	dwc->gadget.ops			= &dwc3_gadget_ops;
	dwc->gadget.speed		= USB_SPEED_UNKNOWN;
	dwc->gadget.sg_supported	= true;
	dwc->gadget.name		= "dwc3-gadget";

	/*
	 * FIXME We might be setting max_speed to <SUPER, however versions
	 * <2.20a of dwc3 have an issue with metastability (documented
	 * elsewhere in this driver) which tells us we can't set max speed to
	 * anything lower than SUPER.
	 *
	 * Because gadget.max_speed is only used by composite.c and function
	 * drivers (i.e. it won't go into dwc3's registers) we are allowing this
	 * to happen so we avoid sending SuperSpeed Capability descriptor
	 * together with our BOS descriptor as that could confuse host into
	 * thinking we can handle super speed.
	 *
	 * Note that, in fact, we won't even support GetBOS requests when speed
	 * is less than super speed because we don't have means, yet, to tell
	 * composite.c that we are USB 2.0 + LPM ECN.
	 */
	if (dwc->revision < DWC3_REVISION_220A)
		dwc3_trace(trace_dwc3_gadget,
				"Changing max_speed on rev %08x\n",
				dwc->revision);

	dwc->gadget.max_speed		= dwc->maximum_speed;

	/*
	 * Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize
	 * on ep out.
	 */
	dwc->gadget.quirk_ep_out_aligned_size = true;

	/*
	 * REVISIT: Here we should clear all pending IRQs to be
	 * sure we're starting from a well known location.
	 */

	ret = dwc3_gadget_init_endpoints(dwc);
	if (ret)
		goto err5;

	ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
	if (ret) {
		dev_err(dwc->dev, "failed to register udc\n");
		goto err5;
	}

	if (dwc->dotg) {
		ret = otg_set_peripheral(&dwc->dotg->otg, &dwc->gadget);
		if (ret) {
			dev_err(dwc->dev, "failed to set otg peripheral\n");
			goto err6;
		}
	}

	return 0;

err6:
	usb_del_gadget_udc(&dwc->gadget);
err5:
	dwc3_gadget_free_endpoints(dwc);
	kfree(dwc->zlp_buf);	
err4:	
	dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
			dwc->ep0_bounce, dwc->ep0_bounce_addr);
err3:
	kfree(dwc->setup_buf);

err2:
	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
			dwc->ep0_trb, dwc->ep0_trb_addr);

err1:
	dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
			dwc->ctrl_req, dwc->ctrl_req_addr);

err0:
	return ret;
}

/* -------------------------------------------------------------------------- */

void dwc3_gadget_exit(struct dwc3 *dwc)
{
	if (dwc->dotg)
		otg_set_peripheral(&dwc->dotg->otg, NULL);

	usb_del_gadget_udc(&dwc->gadget);

	dwc3_gadget_free_endpoints(dwc);

	dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
			dwc->ep0_bounce, dwc->ep0_bounce_addr);

	kfree(dwc->setup_buf);
	kfree(dwc->zlp_buf);

	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
			dwc->ep0_trb, dwc->ep0_trb_addr);

	dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
			dwc->ctrl_req, dwc->ctrl_req_addr);
}

int dwc3_gadget_suspend(struct dwc3 *dwc)
{
	if (dwc->pullups_connected) {
		dwc3_gadget_disable_irq(dwc);
		dwc3_gadget_run_stop(dwc, true, true);
	}

	__dwc3_gadget_ep_disable(dwc->eps[1]);
	__dwc3_gadget_ep_disable(dwc->eps[0]);

	dwc->dcfg = dwc3_readl(dwc->regs, DWC3_DCFG);

	return 0;
}

int dwc3_gadget_resume(struct dwc3 *dwc)
{
	struct dwc3_ep		*dep;
	int			ret;

	/* Start with SuperSpeed Default */
	dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);

	dep = dwc->eps[0];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
			false);
	if (ret)
		goto err0;

	dep = dwc->eps[1];
	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
			false);
	if (ret)
		goto err1;

	/* begin to receive SETUP packets */
	dwc->ep0state = EP0_SETUP_PHASE;
	dwc3_ep0_out_start(dwc);

	dwc3_writel(dwc->regs, DWC3_DCFG, dwc->dcfg);

	if (dwc->pullups_connected) {
		dwc3_gadget_enable_irq(dwc);
		dwc3_gadget_run_stop(dwc, true, false);
	}

	return 0;

err1:
	__dwc3_gadget_ep_disable(dwc->eps[0]);

err0:
	return ret;
}

void dwc3_gadget_disconnect_proc(struct dwc3 *dwc)
{
	int			reg;

	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
	reg &= ~DWC3_DCTL_INITU1ENA;
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	reg &= ~DWC3_DCTL_INITU2ENA;
	dwc3_writel(dwc->regs, DWC3_DCTL, reg);

	if (dwc->gadget_driver && dwc->gadget_driver->disconnect)
		dwc->gadget_driver->disconnect(&dwc->gadget);

	dwc->start_config_issued = false;

	dwc->gadget.speed = USB_SPEED_UNKNOWN;
	dwc->setup_packet_pending = false;

	complete(&dwc->disconnect);
}