[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/usb/dwc3/gadget.c b/src/kernel/linux/v4.14/drivers/usb/dwc3/gadget.c
new file mode 100644
index 0000000..4a42368
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/usb/dwc3/gadget.c
@@ -0,0 +1,3375 @@
+/*
+ * 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>
+
+#include "debug.h"
+#include "core.h"
+#include "gadget.h"
+#include "io.h"
+
+/**
+ * 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);
+	}
+
+	return -ETIMEDOUT;
+}
+
+/**
+ * dwc3_ep_inc_trb - increment a trb index.
+ * @index: Pointer to the TRB index to increment.
+ *
+ * The index should never point to the link TRB. After incrementing,
+ * if it is point to the link TRB, wrap around to the beginning. The
+ * link TRB is always at the last TRB entry.
+ */
+static void dwc3_ep_inc_trb(u8 *index)
+{
+	(*index)++;
+	if (*index == (DWC3_TRB_NUM - 1))
+		*index = 0;
+}
+
+/**
+ * dwc3_ep_inc_enq - increment endpoint's enqueue pointer
+ * @dep: The endpoint whose enqueue pointer we're incrementing
+ */
+static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
+{
+	dwc3_ep_inc_trb(&dep->trb_enqueue);
+}
+
+/**
+ * dwc3_ep_inc_deq - increment endpoint's dequeue pointer
+ * @dep: The endpoint whose enqueue pointer we're incrementing
+ */
+static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
+{
+	dwc3_ep_inc_trb(&dep->trb_dequeue);
+}
+
+void dwc3_gadget_del_and_unmap_request(struct dwc3_ep *dep,
+		struct dwc3_request *req, int status)
+{
+	struct dwc3			*dwc = dep->dwc;
+
+	req->started = false;
+	list_del(&req->list);
+	req->remaining = 0;
+	req->unaligned = false;
+	req->zero = false;
+
+	if (req->request.status == -EINPROGRESS)
+		req->request.status = status;
+
+	if (req->trb)
+		usb_gadget_unmap_request_by_dev(dwc->sysdev,
+				&req->request, req->direction);
+
+	req->trb = NULL;
+	trace_dwc3_gadget_giveback(req);
+
+	if (dep->number > 1)
+		pm_runtime_put(dwc->dev);
+}
+
+/**
+ * dwc3_gadget_giveback - call struct usb_request's ->complete callback
+ * @dep: The endpoint to whom the request belongs to
+ * @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 dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
+		int status)
+{
+	struct dwc3			*dwc = dep->dwc;
+
+	dwc3_gadget_del_and_unmap_request(dep, req, status);
+
+	spin_unlock(&dwc->lock);
+	usb_gadget_giveback_request(&dep->endpoint, &req->request);
+	spin_lock(&dwc->lock);
+}
+
+/**
+ * dwc3_send_gadget_generic_command - issue a generic command for the controller
+ * @dwc: pointer to the controller context
+ * @cmd: the command to be issued
+ * @param: command parameter
+ *
+ * Caller should take care of locking. Issue @cmd with a given @param to @dwc
+ * and wait for its completion.
+ */
+int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
+{
+	u32		timeout = 500;
+	int		status = 0;
+	int		ret = 0;
+	u32		reg;
+
+	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)) {
+			status = DWC3_DGCMD_STATUS(reg);
+			if (status)
+				ret = -EINVAL;
+			break;
+		}
+	} while (--timeout);
+
+	if (!timeout) {
+		ret = -ETIMEDOUT;
+		status = -ETIMEDOUT;
+	}
+
+	trace_dwc3_gadget_generic_cmd(cmd, param, status);
+
+	return ret;
+}
+
+static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
+
+/**
+ * dwc3_send_gadget_ep_cmd - issue an endpoint command
+ * @dep: the endpoint to which the command is going to be issued
+ * @cmd: the command to be issued
+ * @params: parameters to the command
+ *
+ * Caller should handle locking. This function will issue @cmd with given
+ * @params to @dep and wait for its completion.
+ */
+int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
+		struct dwc3_gadget_ep_cmd_params *params)
+{
+	const struct usb_endpoint_descriptor *desc = dep->endpoint.desc;
+	struct dwc3		*dwc = dep->dwc;
+	u32			timeout = 5000;
+	u32			saved_config = 0;
+	u32			reg;
+
+	int			cmd_status = 0;
+	int			ret = -EINVAL;
+
+	/*
+	 * When operating in USB 2.0 speeds (HS/FS), if GUSB2PHYCFG.ENBLSLPM or
+	 * GUSB2PHYCFG.SUSPHY is set, it must be cleared before issuing an
+	 * endpoint command.
+	 *
+	 * Save and clear both GUSB2PHYCFG.ENBLSLPM and GUSB2PHYCFG.SUSPHY
+	 * settings. Restore them after the command is completed.
+	 *
+	 * DWC_usb3 3.30a and DWC_usb31 1.90a programming guide section 3.2.2
+	 */
+	if (dwc->gadget.speed <= USB_SPEED_HIGH) {
+		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+		if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
+			saved_config |= DWC3_GUSB2PHYCFG_SUSPHY;
+			reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
+		}
+
+		if (reg & DWC3_GUSB2PHYCFG_ENBLSLPM) {
+			saved_config |= DWC3_GUSB2PHYCFG_ENBLSLPM;
+			reg &= ~DWC3_GUSB2PHYCFG_ENBLSLPM;
+		}
+
+		if (saved_config)
+			dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+	}
+
+	if (DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_STARTTRANSFER) {
+		int		needs_wakeup;
+
+		needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
+				dwc->link_state == DWC3_LINK_STATE_U2 ||
+				dwc->link_state == DWC3_LINK_STATE_U3);
+
+		if (unlikely(needs_wakeup)) {
+			ret = __dwc3_gadget_wakeup(dwc);
+			dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
+					ret);
+		}
+	}
+
+	dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
+	dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
+	dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
+
+	/*
+	 * Synopsys Databook 2.60a states in section 6.3.2.5.6 of that if we're
+	 * not relying on XferNotReady, we can make use of a special "No
+	 * Response Update Transfer" command where we should clear both CmdAct
+	 * and CmdIOC bits.
+	 *
+	 * With this, we don't need to wait for command completion and can
+	 * straight away issue further commands to the endpoint.
+	 *
+	 * NOTICE: We're making an assumption that control endpoints will never
+	 * make use of Update Transfer command. This is a safe assumption
+	 * because we can never have more than one request at a time with
+	 * Control Endpoints. If anybody changes that assumption, this chunk
+	 * needs to be updated accordingly.
+	 */
+	if (DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_UPDATETRANSFER &&
+			!usb_endpoint_xfer_isoc(desc))
+		cmd &= ~(DWC3_DEPCMD_CMDIOC | DWC3_DEPCMD_CMDACT);
+	else
+		cmd |= DWC3_DEPCMD_CMDACT;
+
+	dwc3_writel(dep->regs, DWC3_DEPCMD, cmd);
+	do {
+		reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
+		if (!(reg & DWC3_DEPCMD_CMDACT)) {
+			cmd_status = DWC3_DEPCMD_STATUS(reg);
+
+			switch (cmd_status) {
+			case 0:
+				ret = 0;
+				break;
+			case DEPEVT_TRANSFER_NO_RESOURCE:
+				ret = -EINVAL;
+				break;
+			case DEPEVT_TRANSFER_BUS_EXPIRY:
+				/*
+				 * SW issues START TRANSFER command to
+				 * isochronous ep with future frame interval. If
+				 * future interval time has already passed when
+				 * core receives the command, it will respond
+				 * with an error status of 'Bus Expiry'.
+				 *
+				 * Instead of always returning -EINVAL, let's
+				 * give a hint to the gadget driver that this is
+				 * the case by returning -EAGAIN.
+				 */
+				ret = -EAGAIN;
+				break;
+			default:
+				dev_WARN(dwc->dev, "UNKNOWN cmd status\n");
+			}
+
+			break;
+		}
+	} while (--timeout);
+
+	if (timeout == 0) {
+		ret = -ETIMEDOUT;
+		cmd_status = -ETIMEDOUT;
+	}
+
+	trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
+
+	if (ret == 0) {
+		switch (DWC3_DEPCMD_CMD(cmd)) {
+		case DWC3_DEPCMD_STARTTRANSFER:
+			dep->flags |= DWC3_EP_TRANSFER_STARTED;
+			break;
+		case DWC3_DEPCMD_ENDTRANSFER:
+			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
+			break;
+		default:
+			/* nothing */
+			break;
+		}
+	}
+
+	if (saved_config) {
+		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+		reg |= saved_config;
+		dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+	}
+
+	return ret;
+}
+
+static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
+{
+	struct dwc3 *dwc = dep->dwc;
+	struct dwc3_gadget_ep_cmd_params params;
+	u32 cmd = DWC3_DEPCMD_CLEARSTALL;
+
+	/*
+	 * As of core revision 2.60a the recommended programming model
+	 * is to set the ClearPendIN bit when issuing a Clear Stall EP
+	 * command for IN endpoints. This is to prevent an issue where
+	 * some (non-compliant) hosts may not send ACK TPs for pending
+	 * IN transfers due to a mishandled error condition. Synopsys
+	 * STAR 9000614252.
+	 */
+	if (dep->direction && (dwc->revision >= DWC3_REVISION_260A) &&
+	    (dwc->gadget.speed >= USB_SPEED_SUPER))
+		cmd |= DWC3_DEPCMD_CLEARPENDIN;
+
+	memset(&params, 0, sizeof(params));
+
+	return dwc3_send_gadget_ep_cmd(dep, cmd, &params);
+}
+
+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->sysdev,
+			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->sysdev, 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
+ *
+ * Issue a %DWC3_DEPCMD_DEPSTARTCFG command to @dep. After the command's
+ * completion, it will set Transfer Resource for all available endpoints.
+ *
+ * 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 %DWC3_DEPCMD_DEPSTARTCFG for every
+ * %USB_REQ_SET_CONFIGURATION and %USB_REQ_SET_INTERFACE (8.1.5). This is
+ * incorrect in the scenario of multiple interfaces.
+ *
+ * 2) The databook does not mention doing more %DWC3_DEPCMD_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 %DWC3_DEPCMD_DEPSTARTCFG(0) we can go ahead and do
+ * %DWC3_DEPCMD_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(dep, 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,
+		bool modify, bool restore)
+{
+	const struct usb_ss_ep_comp_descriptor *comp_desc;
+	const struct usb_endpoint_descriptor *desc;
+	struct dwc3_gadget_ep_cmd_params params;
+
+	if (dev_WARN_ONCE(dwc->dev, modify && restore,
+					"Can't modify and restore\n"))
+		return -EINVAL;
+
+	comp_desc = dep->endpoint.comp_desc;
+	desc = dep->endpoint.desc;
+
+	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;
+		params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst - 1);
+	}
+
+	if (modify) {
+		params.param0 |= DWC3_DEPCFG_ACTION_MODIFY;
+	} else if (restore) {
+		params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
+		params.param2 |= dep->saved_state;
+	} else {
+		params.param0 |= DWC3_DEPCFG_ACTION_INIT;
+	}
+
+	if (usb_endpoint_xfer_control(desc))
+		params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
+
+	if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
+		params.param1 |= 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(dep, 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(dep, DWC3_DEPCMD_SETTRANSFRESOURCE,
+			&params);
+}
+
+/**
+ * __dwc3_gadget_ep_enable - initializes a hw endpoint
+ * @dep: endpoint to be initialized
+ * @modify: if true, modify existing endpoint configuration
+ * @restore: if true, restore endpoint configuration from scratch buffer
+ *
+ * Caller should take care of locking. Execute all necessary commands to
+ * initialize a HW endpoint so it can be used by a gadget driver.
+ */
+static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
+		bool modify, bool restore)
+{
+	const struct usb_endpoint_descriptor *desc = dep->endpoint.desc;
+	struct dwc3		*dwc = dep->dwc;
+
+	u32			reg;
+	int			ret;
+
+	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, modify, restore);
+	if (ret)
+		return ret;
+
+	if (!(dep->flags & DWC3_EP_ENABLED)) {
+		struct dwc3_trb	*trb_st_hw;
+		struct dwc3_trb	*trb_link;
+
+		dep->type = usb_endpoint_type(desc);
+		dep->flags |= DWC3_EP_ENABLED;
+		dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
+
+		reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
+		reg |= DWC3_DALEPENA_EP(dep->number);
+		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
+
+		init_waitqueue_head(&dep->wait_end_transfer);
+
+		if (usb_endpoint_xfer_control(desc))
+			goto out;
+
+		/* Initialize the TRB ring */
+		dep->trb_dequeue = 0;
+		dep->trb_enqueue = 0;
+		memset(dep->trb_pool, 0,
+		       sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
+
+		/* Link TRB. The HWO bit is never reset */
+		trb_st_hw = &dep->trb_pool[0];
+
+		trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
+		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;
+	}
+
+	/*
+	 * Issue StartTransfer here with no-op TRB so we can always rely on No
+	 * Response Update Transfer command.
+	 */
+	if (usb_endpoint_xfer_bulk(desc)) {
+		struct dwc3_gadget_ep_cmd_params params;
+		struct dwc3_trb	*trb;
+		dma_addr_t trb_dma;
+		u32 cmd;
+
+		memset(&params, 0, sizeof(params));
+		trb = &dep->trb_pool[0];
+		trb_dma = dwc3_trb_dma_offset(dep, trb);
+
+		params.param0 = upper_32_bits(trb_dma);
+		params.param1 = lower_32_bits(trb_dma);
+
+		cmd = DWC3_DEPCMD_STARTTRANSFER;
+
+		ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
+		if (ret < 0)
+			return ret;
+
+		dep->flags |= DWC3_EP_BUSY;
+
+		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
+		WARN_ON_ONCE(!dep->resource_index);
+	}
+
+
+out:
+	trace_dwc3_gadget_ep_enable(dep);
+
+	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;
+
+	dwc3_stop_active_transfer(dwc, dep->number, true);
+
+	/* - giveback all requests to gadget driver */
+	while (!list_empty(&dep->started_list)) {
+		req = next_request(&dep->started_list);
+
+		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
+	}
+
+	while (!list_empty(&dep->pending_list)) {
+		req = next_request(&dep->pending_list);
+
+		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
+	}
+}
+
+/**
+ * __dwc3_gadget_ep_disable - disables a hw endpoint
+ * @dep: the endpoint to disable
+ *
+ * This function undoes what __dwc3_gadget_ep_enable did and also removes
+ * requests which are currently being processed by 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;
+
+	trace_dwc3_gadget_ep_disable(dep);
+
+	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->stream_capable = false;
+	dep->type = 0;
+	dep->flags &= DWC3_EP_END_TRANSFER_PENDING;
+
+	/* Clear out the ep descriptors for non-ep0 */
+	if (dep->number > 1) {
+		dep->endpoint.comp_desc = NULL;
+		dep->endpoint.desc = NULL;
+	}
+
+	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 (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
+					"%s is already enabled\n",
+					dep->name))
+		return 0;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	ret = __dwc3_gadget_ep_enable(dep, 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 (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
+					"%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;
+
+	dep->allocated_requests++;
+
+	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);
+	struct dwc3_ep			*dep = to_dwc3_ep(ep);
+
+	dep->allocated_requests--;
+	trace_dwc3_free_request(req);
+	kfree(req);
+}
+
+static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep);
+
+static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb,
+		dma_addr_t dma, unsigned length, unsigned chain, unsigned node,
+		unsigned stream_id, unsigned short_not_ok, unsigned no_interrupt)
+{
+	struct dwc3		*dwc = dep->dwc;
+	struct usb_gadget	*gadget = &dwc->gadget;
+	enum usb_device_speed	speed = gadget->speed;
+
+	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;
+
+			/*
+			 * USB Specification 2.0 Section 5.9.2 states that: "If
+			 * there is only a single transaction in the microframe,
+			 * only a DATA0 data packet PID is used.  If there are
+			 * two transactions per microframe, DATA1 is used for
+			 * the first transaction data packet and DATA0 is used
+			 * for the second transaction data packet.  If there are
+			 * three transactions per microframe, DATA2 is used for
+			 * the first transaction data packet, DATA1 is used for
+			 * the second, and DATA0 is used for the third."
+			 *
+			 * IOW, we should satisfy the following cases:
+			 *
+			 * 1) length <= maxpacket
+			 *	- DATA0
+			 *
+			 * 2) maxpacket < length <= (2 * maxpacket)
+			 *	- DATA1, DATA0
+			 *
+			 * 3) (2 * maxpacket) < length <= (3 * maxpacket)
+			 *	- DATA2, DATA1, DATA0
+			 */
+			if (speed == USB_SPEED_HIGH) {
+				struct usb_ep *ep = &dep->endpoint;
+				unsigned int mult = ep->mult - 1;
+				unsigned int maxp = usb_endpoint_maxp(ep->desc);
+
+				if (length <= (2 * maxp))
+					mult--;
+
+				if (length <= maxp)
+					mult--;
+
+				trb->size |= DWC3_TRB_SIZE_PCM1(mult);
+			}
+		} else {
+			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
+		}
+
+		/* always enable Interrupt on Missed ISOC */
+		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
+		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 :)
+		 */
+		dev_WARN(dwc->dev, "Unknown endpoint type %d\n",
+				usb_endpoint_type(dep->endpoint.desc));
+	}
+
+	/*
+	 * Enable Continue on Short Packet
+	 * when endpoint is not a stream capable
+	 */
+	if (usb_endpoint_dir_out(dep->endpoint.desc)) {
+		if (!dep->stream_capable)
+			trb->ctrl |= DWC3_TRB_CTRL_CSP;
+
+		if (short_not_ok)
+			trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
+	}
+
+	if ((!no_interrupt && !chain) ||
+			(dwc3_calc_trbs_left(dep) == 1))
+		trb->ctrl |= DWC3_TRB_CTRL_IOC;
+
+	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(stream_id);
+
+	trb->ctrl |= DWC3_TRB_CTRL_HWO;
+
+	dwc3_ep_inc_enq(dep);
+
+	trace_dwc3_prepare_trb(dep, trb);
+}
+
+/**
+ * dwc3_prepare_one_trb - setup one TRB from one request
+ * @dep: endpoint for which this request is prepared
+ * @req: dwc3_request pointer
+ * @chain: should this TRB be chained to the next?
+ * @node: only for isochronous endpoints. First TRB needs different type.
+ */
+static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
+		struct dwc3_request *req, unsigned chain, unsigned node)
+{
+	struct dwc3_trb		*trb;
+	unsigned		length = req->request.length;
+	unsigned		stream_id = req->request.stream_id;
+	unsigned		short_not_ok = req->request.short_not_ok;
+	unsigned		no_interrupt = req->request.no_interrupt;
+	dma_addr_t		dma = req->request.dma;
+
+	trb = &dep->trb_pool[dep->trb_enqueue];
+
+	if (!req->trb) {
+		dwc3_gadget_move_started_request(req);
+		req->trb = trb;
+		req->trb_dma = dwc3_trb_dma_offset(dep, trb);
+		dep->queued_requests++;
+	}
+
+	__dwc3_prepare_one_trb(dep, trb, dma, length, chain, node,
+			stream_id, short_not_ok, no_interrupt);
+}
+
+/**
+ * dwc3_ep_prev_trb - returns the previous TRB in the ring
+ * @dep: The endpoint with the TRB ring
+ * @index: The index of the current TRB in the ring
+ *
+ * Returns the TRB prior to the one pointed to by the index. If the
+ * index is 0, we will wrap backwards, skip the link TRB, and return
+ * the one just before that.
+ */
+static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
+{
+	u8 tmp = index;
+
+	if (!tmp)
+		tmp = DWC3_TRB_NUM - 1;
+
+	return &dep->trb_pool[tmp - 1];
+}
+
+static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
+{
+	struct dwc3_trb		*tmp;
+	u8			trbs_left;
+
+	/*
+	 * If enqueue & dequeue are equal than it is either full or empty.
+	 *
+	 * One way to know for sure is if the TRB right before us has HWO bit
+	 * set or not. If it has, then we're definitely full and can't fit any
+	 * more transfers in our ring.
+	 */
+	if (dep->trb_enqueue == dep->trb_dequeue) {
+		tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
+		if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
+			return 0;
+
+		return DWC3_TRB_NUM - 1;
+	}
+
+	trbs_left = dep->trb_dequeue - dep->trb_enqueue;
+	trbs_left &= (DWC3_TRB_NUM - 1);
+
+	if (dep->trb_dequeue < dep->trb_enqueue)
+		trbs_left--;
+
+	return trbs_left;
+}
+
+static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
+		struct dwc3_request *req)
+{
+	struct scatterlist *sg = req->sg;
+	struct scatterlist *s;
+	int		i;
+
+	for_each_sg(sg, s, req->num_pending_sgs, i) {
+		unsigned int length = req->request.length;
+		unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
+		unsigned int rem = length % maxp;
+		unsigned chain = true;
+
+		if (sg_is_last(s))
+			chain = false;
+
+		if (rem && usb_endpoint_dir_out(dep->endpoint.desc) && !chain) {
+			struct dwc3	*dwc = dep->dwc;
+			struct dwc3_trb	*trb;
+
+			req->unaligned = true;
+
+			/* prepare normal TRB */
+			dwc3_prepare_one_trb(dep, req, true, i);
+
+			/* Now prepare one extra TRB to align transfer size */
+			trb = &dep->trb_pool[dep->trb_enqueue];
+			__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr,
+					maxp - rem, false, 1,
+					req->request.stream_id,
+					req->request.short_not_ok,
+					req->request.no_interrupt);
+		} else {
+			dwc3_prepare_one_trb(dep, req, chain, i);
+		}
+
+		if (!dwc3_calc_trbs_left(dep))
+			break;
+	}
+}
+
+static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
+		struct dwc3_request *req)
+{
+	unsigned int length = req->request.length;
+	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
+	unsigned int rem = length % maxp;
+
+	if ((!length || rem) && usb_endpoint_dir_out(dep->endpoint.desc)) {
+		struct dwc3	*dwc = dep->dwc;
+		struct dwc3_trb	*trb;
+
+		req->unaligned = true;
+
+		/* prepare normal TRB */
+		dwc3_prepare_one_trb(dep, req, true, 0);
+
+		/* Now prepare one extra TRB to align transfer size */
+		trb = &dep->trb_pool[dep->trb_enqueue];
+		__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, maxp - rem,
+				false, 1, req->request.stream_id,
+				req->request.short_not_ok,
+				req->request.no_interrupt);
+	} else if (req->request.zero && req->request.length &&
+		   (IS_ALIGNED(req->request.length,dep->endpoint.maxpacket))) {
+		struct dwc3	*dwc = dep->dwc;
+		struct dwc3_trb	*trb;
+
+		req->zero = true;
+
+		/* prepare normal TRB */
+		dwc3_prepare_one_trb(dep, req, true, 0);
+
+		/* Now prepare one extra TRB to handle ZLP */
+		trb = &dep->trb_pool[dep->trb_enqueue];
+		__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, 0,
+				false, 1, req->request.stream_id,
+				req->request.short_not_ok,
+				req->request.no_interrupt);
+	} else {
+		dwc3_prepare_one_trb(dep, req, false, 0);
+	}
+}
+
+/*
+ * dwc3_prepare_trbs - setup TRBs from requests
+ * @dep: endpoint for which requests are being prepared
+ *
+ * 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)
+{
+	struct dwc3_request	*req, *n;
+
+	BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
+
+	if (!dwc3_calc_trbs_left(dep))
+		return;
+
+	/*
+	 * We can get in a situation where there's a request in the started list
+	 * but there weren't enough TRBs to fully kick it in the first time
+	 * around, so it has been waiting for more TRBs to be freed up.
+	 *
+	 * In that case, we should check if we have a request with pending_sgs
+	 * in the started list and prepare TRBs for that request first,
+	 * otherwise we will prepare TRBs completely out of order and that will
+	 * break things.
+	 */
+	list_for_each_entry(req, &dep->started_list, list) {
+		if (req->num_pending_sgs > 0)
+			dwc3_prepare_one_trb_sg(dep, req);
+
+		if (!dwc3_calc_trbs_left(dep))
+			return;
+	}
+
+	list_for_each_entry_safe(req, n, &dep->pending_list, list) {
+		struct dwc3	*dwc = dep->dwc;
+		int		ret;
+
+		ret = usb_gadget_map_request_by_dev(dwc->sysdev, &req->request,
+						    dep->direction);
+		if (ret)
+			return;
+
+		req->sg			= req->request.sg;
+		req->num_pending_sgs	= req->request.num_mapped_sgs;
+
+		if (req->num_pending_sgs > 0)
+			dwc3_prepare_one_trb_sg(dep, req);
+		else
+			dwc3_prepare_one_trb_linear(dep, req);
+
+		if (!dwc3_calc_trbs_left(dep))
+			return;
+	}
+}
+
+static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param)
+{
+	struct dwc3_gadget_ep_cmd_params params;
+	struct dwc3_request		*req;
+	int				starting;
+	int				ret;
+	u32				cmd;
+
+	starting = !(dep->flags & DWC3_EP_BUSY);
+
+	dwc3_prepare_trbs(dep);
+	req = next_request(&dep->started_list);
+	if (!req) {
+		dep->flags |= DWC3_EP_PENDING_REQUEST;
+		return 0;
+	}
+
+	memset(&params, 0, sizeof(params));
+
+	if (starting) {
+		params.param0 = upper_32_bits(req->trb_dma);
+		params.param1 = lower_32_bits(req->trb_dma);
+		cmd = DWC3_DEPCMD_STARTTRANSFER |
+			DWC3_DEPCMD_PARAM(cmd_param);
+	} else {
+		cmd = DWC3_DEPCMD_UPDATETRANSFER |
+			DWC3_DEPCMD_PARAM(dep->resource_index);
+	}
+
+	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
+	if (ret < 0) {
+		/*
+		 * 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.
+		 */
+		if (req->trb)
+			memset(req->trb, 0, sizeof(struct dwc3_trb));
+		dep->queued_requests--;
+		dwc3_gadget_del_and_unmap_request(dep, req, ret);
+		return ret;
+	}
+
+	dep->flags |= DWC3_EP_BUSY;
+
+	if (starting) {
+		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
+		WARN_ON_ONCE(!dep->resource_index);
+	}
+
+	return 0;
+}
+
+static int __dwc3_gadget_get_frame(struct dwc3 *dwc)
+{
+	u32			reg;
+
+	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+	return DWC3_DSTS_SOFFN(reg);
+}
+
+static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
+		struct dwc3_ep *dep, u32 cur_uf)
+{
+	u32 uf;
+
+	if (list_empty(&dep->pending_list)) {
+		dev_info(dwc->dev, "%s: ran out of requests\n",
+				dep->name);
+		dep->flags |= DWC3_EP_PENDING_REQUEST;
+		return;
+	}
+
+	/*
+	 * Schedule the first trb for one interval in the future or at
+	 * least 4 microframes.
+	 */
+	uf = cur_uf + max_t(u32, 4, dep->interval);
+
+	__dwc3_gadget_kick_transfer(dep, uf);
+}
+
+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 = 0;
+
+	if (!dep->endpoint.desc) {
+		dev_err(dwc->dev, "%s: can't queue to disabled endpoint\n",
+				dep->name);
+		return -ESHUTDOWN;
+	}
+
+	if (WARN(req->dep != dep, "request %pK belongs to '%s'\n",
+				&req->request, req->dep->name))
+		return -EINVAL;
+
+	pm_runtime_get(dwc->dev);
+
+	req->request.actual	= 0;
+	req->request.status	= -EINPROGRESS;
+	req->direction		= dep->direction;
+	req->epnum		= dep->number;
+
+	trace_dwc3_ep_queue(req);
+
+	list_add_tail(&req->list, &dep->pending_list);
+
+	/*
+	 * NOTICE: Isochronous endpoints should NEVER be prestarted. We must
+	 * wait for a XferNotReady event so we will know what's the current
+	 * (micro-)frame number.
+	 *
+	 * Without this trick, we are very, very likely gonna get Bus Expiry
+	 * errors which will force us issue EndTransfer command.
+	 */
+	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
+		if ((dep->flags & DWC3_EP_PENDING_REQUEST)) {
+			if (dep->flags & DWC3_EP_TRANSFER_STARTED) {
+				dwc3_stop_active_transfer(dwc, dep->number, true);
+				dep->flags = DWC3_EP_ENABLED;
+			} else {
+				u32 cur_uf;
+
+				cur_uf = __dwc3_gadget_get_frame(dwc);
+				__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
+				dep->flags &= ~DWC3_EP_PENDING_REQUEST;
+			}
+			return 0;
+		}
+
+		if ((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);
+		}
+
+		goto out;
+	}
+
+	if (!dwc3_calc_trbs_left(dep))
+		return 0;
+
+	ret = __dwc3_gadget_kick_transfer(dep, 0);
+out:
+	if (ret == -EBUSY)
+		ret = 0;
+
+	return ret;
+}
+
+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);
+	ret = __dwc3_gadget_ep_queue(dep, req);
+	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->pending_list, list) {
+		if (r == req)
+			break;
+	}
+
+	if (r != req) {
+		list_for_each_entry(r, &dep->started_list, list) {
+			if (r == req)
+				break;
+		}
+		if (r == req) {
+			/* wait until it is processed */
+			dwc3_stop_active_transfer(dwc, dep->number, true);
+
+			/*
+			 * If request was already started, this means we had to
+			 * stop the transfer. With that we also need to ignore
+			 * all TRBs used by the request, however TRBs can only
+			 * be modified after completion of END_TRANSFER
+			 * command. So what we do here is that we wait for
+			 * END_TRANSFER completion and only after that, we jump
+			 * over TRBs by clearing HWO and incrementing dequeue
+			 * pointer.
+			 *
+			 * Note that we have 2 possible types of transfers here:
+			 *
+			 * i) Linear buffer request
+			 * ii) SG-list based request
+			 *
+			 * SG-list based requests will have r->num_pending_sgs
+			 * set to a valid number (> 0). Linear requests,
+			 * normally use a single TRB.
+			 *
+			 * For each of these two cases, if r->unaligned flag is
+			 * set, one extra TRB has been used to align transfer
+			 * size to wMaxPacketSize.
+			 *
+			 * All of these cases need to be taken into
+			 * consideration so we don't mess up our TRB ring
+			 * pointers.
+			 */
+			wait_event_lock_irq(dep->wait_end_transfer,
+					!(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
+					dwc->lock);
+
+			if (!r->trb)
+				goto out0;
+
+			if (r->num_pending_sgs) {
+				struct dwc3_trb *trb;
+				int i = 0;
+
+				for (i = 0; i < r->num_pending_sgs; i++) {
+					trb = r->trb + i;
+					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+					dwc3_ep_inc_deq(dep);
+				}
+
+				if (r->unaligned || r->zero) {
+					trb = r->trb + r->num_pending_sgs + 1;
+					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+					dwc3_ep_inc_deq(dep);
+				}
+			} else {
+				struct dwc3_trb *trb = r->trb;
+
+				trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+				dwc3_ep_inc_deq(dep);
+
+				if (r->unaligned || r->zero) {
+					trb = r->trb + 1;
+					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+					dwc3_ep_inc_deq(dep);
+				}
+			}
+			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 */
+	dep->queued_requests--;
+	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 (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) {
+		struct dwc3_trb *trb;
+
+		unsigned transfer_in_flight;
+		unsigned started;
+
+		if (dep->number > 1)
+			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
+		else
+			trb = &dwc->ep0_trb[dep->trb_enqueue];
+
+		transfer_in_flight = trb->ctrl & DWC3_TRB_CTRL_HWO;
+		started = !list_empty(&dep->started_list);
+
+		if (!protocol && ((dep->direction && transfer_in_flight) ||
+				(!dep->direction && started))) {
+			return -EAGAIN;
+		}
+
+		ret = dwc3_send_gadget_ep_cmd(dep, 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_clear_stall_ep_cmd(dep);
+		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);
+
+	return __dwc3_gadget_get_frame(dwc);
+}
+
+static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
+{
+	int			retries;
+
+	int			ret;
+	u32			reg;
+
+	u8			link_state;
+
+	/*
+	 * 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);
+
+	link_state = DWC3_DSTS_USBLNKST(reg);
+
+	switch (link_state) {
+	case DWC3_LINK_STATE_RESET:
+	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
+	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
+	case DWC3_LINK_STATE_RESUME:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	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");
+		return ret;
+	}
+
+	/* 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 */
+	retries = 20000;
+
+	while (retries--) {
+		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");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int dwc3_gadget_wakeup(struct usb_gadget *g)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+	int			ret;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	ret = __dwc3_gadget_wakeup(dwc);
+	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_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
+{
+	u32			reg;
+	u32			timeout = 500;
+
+	if (pm_runtime_suspended(dwc->dev))
+		return 0;
+
+	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+	if (is_on) {
+		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 {
+		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);
+		reg &= DWC3_DSTS_DEVCTRLHLT;
+	} while (--timeout && !(!is_on ^ !reg));
+
+	if (!timeout)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+	int			ret;
+
+	is_on = !!is_on;
+
+	/*
+	 * Per databook, when we want to stop the gadget, if a control transfer
+	 * is still in process, complete it and get the core into setup phase.
+	 */
+	if (!is_on && dwc->ep0state != EP0_SETUP_PHASE) {
+		reinit_completion(&dwc->ep0_in_setup);
+
+		ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
+				msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
+		if (ret == 0) {
+			dev_err(dwc->dev, "timed out waiting for SETUP phase\n");
+			return -ETIMEDOUT;
+		}
+	}
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	ret = dwc3_gadget_run_stop(dwc, is_on, false);
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	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_CONNECTDONEEN |
+			DWC3_DEVTEN_USBRSTEN |
+			DWC3_DEVTEN_DISCONNEVTEN);
+
+	if (dwc->revision < DWC3_REVISION_250A)
+		reg |= DWC3_DEVTEN_ULSTCNGEN;
+
+	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 irqreturn_t dwc3_interrupt(int irq, void *_dwc);
+static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
+
+/**
+ * dwc3_gadget_setup_nump - calculate and initialize NUMP field of %DWC3_DCFG
+ * @dwc: pointer to our context structure
+ *
+ * The following looks like complex but it's actually very simple. In order to
+ * calculate the number of packets we can burst at once on OUT transfers, we're
+ * gonna use RxFIFO size.
+ *
+ * To calculate RxFIFO size we need two numbers:
+ * MDWIDTH = size, in bits, of the internal memory bus
+ * RAM2_DEPTH = depth, in MDWIDTH, of internal RAM2 (where RxFIFO sits)
+ *
+ * Given these two numbers, the formula is simple:
+ *
+ * RxFIFO Size = (RAM2_DEPTH * MDWIDTH / 8) - 24 - 16;
+ *
+ * 24 bytes is for 3x SETUP packets
+ * 16 bytes is a clock domain crossing tolerance
+ *
+ * Given RxFIFO Size, NUMP = RxFIFOSize / 1024;
+ */
+static void dwc3_gadget_setup_nump(struct dwc3 *dwc)
+{
+	u32 ram2_depth;
+	u32 mdwidth;
+	u32 nump;
+	u32 reg;
+
+	ram2_depth = DWC3_GHWPARAMS7_RAM2_DEPTH(dwc->hwparams.hwparams7);
+	mdwidth = DWC3_GHWPARAMS0_MDWIDTH(dwc->hwparams.hwparams0);
+
+	nump = ((ram2_depth * mdwidth / 8) - 24 - 16) / 1024;
+	nump = min_t(u32, nump, 16);
+
+	/* update NumP */
+	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
+	reg &= ~DWC3_DCFG_NUMP_MASK;
+	reg |= nump << DWC3_DCFG_NUMP_SHIFT;
+	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+}
+
+static int __dwc3_gadget_start(struct dwc3 *dwc)
+{
+	struct dwc3_ep		*dep;
+	int			ret = 0;
+	u32			reg;
+
+	/*
+	 * Use IMOD if enabled via dwc->imod_interval. Otherwise, if
+	 * the core supports IMOD, disable it.
+	 */
+	if (dwc->imod_interval) {
+		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), dwc->imod_interval);
+		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB);
+	} else if (dwc3_has_imod(dwc)) {
+		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), 0);
+	}
+
+	/*
+	 * We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP
+	 * field instead of letting dwc3 itself calculate that automatically.
+	 *
+	 * This way, we maximize the chances that we'll be able to get several
+	 * bursts of data without going through any sort of endpoint throttling.
+	 */
+	reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG);
+	reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL;
+	dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg);
+
+	dwc3_gadget_setup_nump(dwc);
+
+	/* Start with SuperSpeed Default */
+	dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
+
+	dep = dwc->eps[0];
+	ret = __dwc3_gadget_ep_enable(dep, 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, 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;
+	dwc->link_state = DWC3_LINK_STATE_SS_DIS;
+	dwc3_ep0_out_start(dwc);
+
+	dwc3_gadget_enable_irq(dwc);
+
+	return 0;
+
+err1:
+	__dwc3_gadget_ep_disable(dwc->eps[0]);
+
+err0:
+	return ret;
+}
+
+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 = dwc->irq_gadget;
+	ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
+			IRQF_SHARED, "dwc3", dwc->ev_buf);
+	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;
+
+	if (pm_runtime_active(dwc->dev))
+		__dwc3_gadget_start(dwc);
+
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return 0;
+
+err1:
+	spin_unlock_irqrestore(&dwc->lock, flags);
+	free_irq(irq, dwc);
+
+err0:
+	return ret;
+}
+
+static void __dwc3_gadget_stop(struct dwc3 *dwc)
+{
+	dwc3_gadget_disable_irq(dwc);
+	__dwc3_gadget_ep_disable(dwc->eps[0]);
+	__dwc3_gadget_ep_disable(dwc->eps[1]);
+}
+
+static int dwc3_gadget_stop(struct usb_gadget *g)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+	int			epnum;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+
+	if (pm_runtime_suspended(dwc->dev))
+		goto out;
+
+	__dwc3_gadget_stop(dwc);
+
+	for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
+		struct dwc3_ep  *dep = dwc->eps[epnum];
+
+		if (!dep)
+			continue;
+
+		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+			continue;
+
+		wait_event_lock_irq(dep->wait_end_transfer,
+				    !(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
+				    dwc->lock);
+	}
+
+out:
+	dwc->gadget_driver	= NULL;
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	free_irq(dwc->irq_gadget, dwc->ev_buf);
+
+	return 0;
+}
+
+static void dwc3_gadget_set_speed(struct usb_gadget *g,
+				  enum usb_device_speed speed)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+	u32			reg;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	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 &&
+	    !dwc->dis_metastability_quirk) {
+		reg |= DWC3_DCFG_SUPERSPEED;
+	} else {
+		switch (speed) {
+		case USB_SPEED_LOW:
+			reg |= DWC3_DCFG_LOWSPEED;
+			break;
+		case USB_SPEED_FULL:
+			reg |= DWC3_DCFG_FULLSPEED;
+			break;
+		case USB_SPEED_HIGH:
+			reg |= DWC3_DCFG_HIGHSPEED;
+			break;
+		case USB_SPEED_SUPER:
+			reg |= DWC3_DCFG_SUPERSPEED;
+			break;
+		case USB_SPEED_SUPER_PLUS:
+			reg |= DWC3_DCFG_SUPERSPEED_PLUS;
+			break;
+		default:
+			dev_err(dwc->dev, "invalid speed (%d)\n", speed);
+
+			if (dwc->revision & DWC3_REVISION_IS_DWC31)
+				reg |= DWC3_DCFG_SUPERSPEED_PLUS;
+			else
+				reg |= DWC3_DCFG_SUPERSPEED;
+		}
+	}
+	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+
+	spin_unlock_irqrestore(&dwc->lock, flags);
+}
+
+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,
+	.pullup			= dwc3_gadget_pullup,
+	.udc_start		= dwc3_gadget_start,
+	.udc_stop		= dwc3_gadget_stop,
+	.udc_set_speed		= dwc3_gadget_set_speed,
+};
+
+/* -------------------------------------------------------------------------- */
+
+static int dwc3_gadget_init_endpoints(struct dwc3 *dwc, u8 total)
+{
+	struct dwc3_ep			*dep;
+	u8				epnum;
+
+	INIT_LIST_HEAD(&dwc->gadget.ep_list);
+
+	for (epnum = 0; epnum < total; epnum++) {
+		bool			direction = epnum & 1;
+		u8			num = epnum >> 1;
+
+		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+		if (!dep)
+			return -ENOMEM;
+
+		dep->dwc = dwc;
+		dep->number = epnum;
+		dep->direction = direction;
+		dep->regs = dwc->regs + DWC3_DEP_BASE(epnum);
+		dwc->eps[epnum] = dep;
+
+		snprintf(dep->name, sizeof(dep->name), "ep%u%s", num,
+				direction ? "in" : "out");
+
+		dep->endpoint.name = dep->name;
+
+		if (!(dep->number > 1)) {
+			dep->endpoint.desc = &dwc3_gadget_ep0_desc;
+			dep->endpoint.comp_desc = NULL;
+		}
+
+		spin_lock_init(&dep->lock);
+
+		if (num == 0) {
+			usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
+			dep->endpoint.maxburst = 1;
+			dep->endpoint.ops = &dwc3_gadget_ep0_ops;
+			if (!direction)
+				dwc->gadget.ep0 = &dep->endpoint;
+		} else if (direction) {
+			int mdwidth;
+			int kbytes;
+			int size;
+			int ret;
+
+			mdwidth = DWC3_MDWIDTH(dwc->hwparams.hwparams0);
+			/* MDWIDTH is represented in bits, we need it in bytes */
+			mdwidth /= 8;
+
+			size = dwc3_readl(dwc->regs, DWC3_GTXFIFOSIZ(num));
+			size = DWC3_GTXFIFOSIZ_TXFDEF(size);
+
+			/* FIFO Depth is in MDWDITH bytes. Multiply */
+			size *= mdwidth;
+
+			kbytes = size / 1024;
+			if (kbytes == 0)
+				kbytes = 1;
+
+			/*
+			 * FIFO sizes account an extra MDWIDTH * (kbytes + 1) bytes for
+			 * internal overhead. We don't really know how these are used,
+			 * but documentation say it exists.
+			 */
+			size -= mdwidth * (kbytes + 1);
+			size /= kbytes;
+
+			usb_ep_set_maxpacket_limit(&dep->endpoint, size);
+
+			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;
+		} 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 (num == 0) {
+			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->pending_list);
+		INIT_LIST_HEAD(&dep->started_list);
+	}
+
+	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,
+		int chain)
+{
+	unsigned int		count;
+	unsigned int		s_pkt = 0;
+	unsigned int		trb_status;
+
+	dwc3_ep_inc_deq(dep);
+
+	if (req->trb == trb)
+		dep->queued_requests--;
+
+	trace_dwc3_complete_trb(dep, trb);
+
+	/*
+	 * If we're in the middle of series of chained TRBs and we
+	 * receive a short transfer along the way, DWC3 will skip
+	 * through all TRBs including the last TRB in the chain (the
+	 * where CHN bit is zero. DWC3 will also avoid clearing HWO
+	 * bit and SW has to do it manually.
+	 *
+	 * We're going to do that here to avoid problems of HW trying
+	 * to use bogus TRBs for transfers.
+	 */
+	if (chain && (trb->ctrl & DWC3_TRB_CTRL_HWO))
+		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+
+	/*
+	 * If we're dealing with unaligned size OUT transfer, we will be left
+	 * with one TRB pending in the ring. We need to manually clear HWO bit
+	 * from that TRB.
+	 */
+	if ((req->zero || req->unaligned) && !(trb->ctrl & DWC3_TRB_CTRL_CHN)) {
+		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
+		return 1;
+	}
+
+	count = trb->size & DWC3_TRB_SIZE_MASK;
+	req->remaining += count;
+
+	if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
+		return 1;
+
+	if (dep->direction) {
+		if (count) {
+			trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
+			if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
+				/*
+				 * 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 pending_list during
+				 * giveback.If any future queued request
+				 * is successfully transferred then we
+				 * will issue UPDATE TRANSFER for all
+				 * request in the pending_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 && !chain)
+		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, *n;
+	struct dwc3_trb		*trb;
+	bool			ioc = false;
+	int			ret = 0;
+
+	list_for_each_entry_safe(req, n, &dep->started_list, list) {
+		unsigned length;
+		int chain;
+
+		length = req->request.length;
+		chain = req->num_pending_sgs > 0;
+		if (chain) {
+			struct scatterlist *sg = req->sg;
+			struct scatterlist *s;
+			unsigned int pending = req->num_pending_sgs;
+			unsigned int i;
+
+			for_each_sg(sg, s, pending, i) {
+				trb = &dep->trb_pool[dep->trb_dequeue];
+
+				if (trb->ctrl & DWC3_TRB_CTRL_HWO)
+					break;
+
+				req->sg = sg_next(s);
+				req->num_pending_sgs--;
+
+				ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
+						event, status, chain);
+				if (ret)
+					break;
+			}
+		} else {
+			trb = &dep->trb_pool[dep->trb_dequeue];
+			ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
+					event, status, chain);
+		}
+
+		if (req->unaligned || req->zero) {
+			trb = &dep->trb_pool[dep->trb_dequeue];
+			ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
+					event, status, false);
+			req->unaligned = false;
+			req->zero = false;
+		}
+
+		req->request.actual = length - req->remaining;
+
+		if ((req->request.actual < length) && req->num_pending_sgs)
+			return __dwc3_gadget_kick_transfer(dep, 0);
+
+		dwc3_gadget_giveback(dep, req, status);
+
+		if (ret) {
+			if ((event->status & DEPEVT_STATUS_IOC) &&
+			    (trb->ctrl & DWC3_TRB_CTRL_IOC))
+				ioc = true;
+			break;
+		}
+	}
+
+	/*
+	 * 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->started_list)) {
+		if (list_empty(&dep->pending_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_ENABLED;
+		}
+		return 1;
+	}
+
+	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) && 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;
+
+	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->started_list))
+				return;
+		}
+
+		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+		reg |= dwc->u1u2;
+		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+
+		dwc->u1u2 = 0;
+	}
+
+	/*
+	 * 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;
+
+	if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
+		int ret;
+
+		ret = __dwc3_gadget_kick_transfer(dep, 0);
+		if (!ret || ret == -EBUSY)
+			return;
+	}
+}
+
+static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
+		const struct dwc3_event_depevt *event)
+{
+	struct dwc3_ep		*dep;
+	u8			epnum = event->endpoint_number;
+	u8			cmd;
+
+	dep = dwc->eps[epnum];
+
+	if (!(dep->flags & DWC3_EP_ENABLED)) {
+		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+			return;
+
+		/* Handle only EPCMDCMPLT when EP disabled */
+		if (event->endpoint_event != DWC3_DEPEVT_EPCMDCMPLT)
+			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_err(dwc->dev, "XferComplete for Isochronous endpoint\n");
+			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 ret;
+
+			ret = __dwc3_gadget_kick_transfer(dep, 0);
+			if (!ret || ret == -EBUSY)
+				return;
+		}
+
+		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;
+		}
+		break;
+	case DWC3_DEPEVT_EPCMDCMPLT:
+		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
+
+		if (cmd == DWC3_DEPCMD_ENDTRANSFER) {
+			dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
+			wake_up(&dep->wait_end_transfer);
+		}
+		break;
+	case DWC3_DEPEVT_RXTXFIFOEVT:
+		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->flags & DWC3_EP_END_TRANSFER_PENDING) ||
+	    !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
+	 *
+	 * As of IP version 3.10a of the DWC_usb3 IP, the controller
+	 * supports a mode to work around the above limitation. The
+	 * software can poll the CMDACT bit in the DEPCMD register
+	 * after issuing a EndTransfer command. This mode is enabled
+	 * by writing GUCTL2[14]. This polling is already done in the
+	 * dwc3_send_gadget_ep_cmd() function so if the mode is
+	 * enabled, the EndTransfer command will have completed upon
+	 * returning from this function and we don't need to delay for
+	 * 100us.
+	 *
+	 * This mode is NOT available on the DWC_usb31 IP.
+	 */
+
+	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(dep, cmd, &params);
+	WARN_ON_ONCE(ret);
+	dep->resource_index = 0;
+	dep->flags &= ~DWC3_EP_BUSY;
+
+	if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A) {
+		dep->flags |= DWC3_EP_END_TRANSFER_PENDING;
+		udelay(100);
+	}
+}
+
+static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
+{
+	u32 epnum;
+
+	for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
+		struct dwc3_ep *dep;
+		int ret;
+
+		dep = dwc->eps[epnum];
+		if (!dep)
+			continue;
+
+		if (!(dep->flags & DWC3_EP_STALL))
+			continue;
+
+		dep->flags &= ~DWC3_EP_STALL;
+
+		ret = dwc3_send_clear_stall_ep_cmd(dep);
+		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);
+
+	dwc->connected = false;
+}
+
+static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
+{
+	u32			reg;
+
+	dwc->connected = true;
+
+	/*
+	 * 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 SETUP_PENDING
+	 * status for EP0 TRBs 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);
+	}
+
+	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_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);
+}
+
+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;
+
+	/*
+	 * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
+	 * each time on Connect Done.
+	 *
+	 * Currently we always use the reset value. If any platform
+	 * wants to set this to a different value, we need to add a
+	 * setting and update GCTL.RAMCLKSEL here.
+	 */
+
+	switch (speed) {
+	case DWC3_DSTS_SUPERSPEED_PLUS:
+		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
+		dwc->gadget.ep0->maxpacket = 512;
+		dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
+		break;
+	case DWC3_DSTS_SUPERSPEED:
+		/*
+		 * 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_DSTS_HIGHSPEED:
+		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
+		dwc->gadget.ep0->maxpacket = 64;
+		dwc->gadget.speed = USB_SPEED_HIGH;
+		break;
+	case DWC3_DSTS_FULLSPEED:
+		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
+		dwc->gadget.ep0->maxpacket = 64;
+		dwc->gadget.speed = USB_SPEED_FULL;
+		break;
+	case DWC3_DSTS_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_DSTS_SUPERSPEED) &&
+	    (speed != DWC3_DSTS_SUPERSPEED_PLUS)) {
+		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 revisions < 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, 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, true, false);
+	if (ret) {
+		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
+		return;
+	}
+
+	/*
+	 * Configure PHY via GUSB3PIPECTLn if required.
+	 *
+	 * Update GTXFIFOSIZn
+	 *
+	 * In both cases reset values should be sufficient.
+	 */
+}
+
+static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
+{
+	/*
+	 * TODO take core out of low power mode when that's
+	 * implemented.
+	 */
+
+	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_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)) {
+			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_U1:
+		if (dwc->speed == USB_SPEED_SUPER)
+			dwc3_suspend_gadget(dwc);
+		break;
+	case DWC3_LINK_STATE_U2:
+	case DWC3_LINK_STATE_U3:
+		dwc3_suspend_gadget(dwc);
+		break;
+	case DWC3_LINK_STATE_RESUME:
+		dwc3_resume_gadget(dwc);
+		break;
+	default:
+		/* do nothing */
+		break;
+	}
+
+	dwc->link_state = next;
+}
+
+static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
+					  unsigned int evtinfo)
+{
+	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
+
+	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
+		dwc3_suspend_gadget(dwc);
+
+	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:
+		dwc3_gadget_disconnect_interrupt(dwc);
+		break;
+	case DWC3_DEVICE_EVENT_RESET:
+		dwc3_gadget_reset_interrupt(dwc);
+		break;
+	case DWC3_DEVICE_EVENT_CONNECT_DONE:
+		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:
+		/* It changed to be suspend event for version 2.30a and above */
+		if (dwc->revision >= DWC3_REVISION_230A) {
+			/*
+			 * Ignore suspend event until the gadget enters into
+			 * USB_STATE_CONFIGURED state.
+			 */
+			if (dwc->gadget.state >= USB_STATE_CONFIGURED)
+				dwc3_gadget_suspend_interrupt(dwc,
+						event->event_info);
+		}
+		break;
+	case DWC3_DEVICE_EVENT_SOF:
+	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
+	case DWC3_DEVICE_EVENT_CMD_CMPL:
+	case DWC3_DEVICE_EVENT_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, dwc);
+
+	if (!event->type.is_devspec)
+		dwc3_endpoint_interrupt(dwc, &event->depevt);
+	else if (event->type.type == DWC3_EVENT_TYPE_DEV)
+		dwc3_gadget_interrupt(dwc, &event->devt);
+	else
+		dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
+}
+
+static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
+{
+	struct dwc3 *dwc = evt->dwc;
+	irqreturn_t ret = IRQ_NONE;
+	int left;
+	u32 reg;
+
+	left = evt->count;
+
+	if (!(evt->flags & DWC3_EVENT_PENDING))
+		return IRQ_NONE;
+
+	while (left > 0) {
+		union dwc3_event event;
+
+		event.raw = *(u32 *) (evt->cache + 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) % evt->length;
+		left -= 4;
+	}
+
+	evt->count = 0;
+	evt->flags &= ~DWC3_EVENT_PENDING;
+	ret = IRQ_HANDLED;
+
+	/* Unmask interrupt */
+	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
+	reg &= ~DWC3_GEVNTSIZ_INTMASK;
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
+
+	if (dwc->imod_interval) {
+		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB);
+		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), dwc->imod_interval);
+	}
+
+	return ret;
+}
+
+static irqreturn_t dwc3_thread_interrupt(int irq, void *_evt)
+{
+	struct dwc3_event_buffer *evt = _evt;
+	struct dwc3 *dwc = evt->dwc;
+	unsigned long flags;
+	irqreturn_t ret = IRQ_NONE;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	ret = dwc3_process_event_buf(evt);
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return ret;
+}
+
+static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
+{
+	struct dwc3 *dwc = evt->dwc;
+	u32 amount;
+	u32 count;
+	u32 reg;
+
+	if (pm_runtime_suspended(dwc->dev)) {
+		pm_runtime_get(dwc->dev);
+		disable_irq_nosync(dwc->irq_gadget);
+		dwc->pending_events = true;
+		return IRQ_HANDLED;
+	}
+
+	/*
+	 * With PCIe legacy interrupt, test shows that top-half irq handler can
+	 * be called again after HW interrupt deassertion. Check if bottom-half
+	 * irq event handler completes before caching new event to prevent
+	 * losing events.
+	 */
+	if (evt->flags & DWC3_EVENT_PENDING)
+		return IRQ_HANDLED;
+
+	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
+	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(0));
+	reg |= DWC3_GEVNTSIZ_INTMASK;
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
+
+	amount = min(count, evt->length - evt->lpos);
+	memcpy(evt->cache + evt->lpos, evt->buf + evt->lpos, amount);
+
+	if (amount < count)
+		memcpy(evt->cache, evt->buf, count - amount);
+
+	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), count);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t dwc3_interrupt(int irq, void *_evt)
+{
+	struct dwc3_event_buffer	*evt = _evt;
+
+	return dwc3_check_event_buf(evt);
+}
+
+static int dwc3_gadget_get_irq(struct dwc3 *dwc)
+{
+	struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
+	int irq;
+
+	irq = platform_get_irq_byname(dwc3_pdev, "peripheral");
+	if (irq > 0)
+		goto out;
+
+	if (irq == -EPROBE_DEFER)
+		goto out;
+
+	irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
+	if (irq > 0)
+		goto out;
+
+	if (irq == -EPROBE_DEFER)
+		goto out;
+
+	irq = platform_get_irq(dwc3_pdev, 0);
+	if (irq > 0)
+		goto out;
+
+	if (irq != -EPROBE_DEFER)
+		dev_err(dwc->dev, "missing peripheral IRQ\n");
+
+	if (!irq)
+		irq = -EINVAL;
+
+out:
+	return irq;
+}
+
+/**
+ * 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;
+	int irq;
+
+	irq = dwc3_gadget_get_irq(dwc);
+	if (irq < 0) {
+		ret = irq;
+		goto err0;
+	}
+
+	dwc->irq_gadget = irq;
+
+	dwc->ep0_trb = dma_alloc_coherent(dwc->sysdev,
+					  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 err0;
+	}
+
+	dwc->setup_buf = kzalloc(DWC3_EP0_SETUP_SIZE, GFP_KERNEL);
+	if (!dwc->setup_buf) {
+		ret = -ENOMEM;
+		goto err1;
+	}
+
+	dwc->bounce = dma_alloc_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE,
+			&dwc->bounce_addr, GFP_KERNEL);
+	if (!dwc->bounce) {
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	init_completion(&dwc->ep0_in_setup);
+
+	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 &&
+	    !dwc->dis_metastability_quirk)
+		dev_info(dwc->dev, "changing max_speed on rev %08x\n",
+				dwc->revision);
+
+	dwc->gadget.max_speed		= dwc->maximum_speed;
+
+	/*
+	 * 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, dwc->num_eps);
+	if (ret)
+		goto err3;
+
+	ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
+	if (ret) {
+		dev_err(dwc->dev, "failed to register udc\n");
+		goto err4;
+	}
+
+	dwc3_gadget_set_speed(&dwc->gadget, dwc->maximum_speed);
+
+	return 0;
+
+err4:
+	dwc3_gadget_free_endpoints(dwc);
+
+err3:
+	dma_free_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE, dwc->bounce,
+			dwc->bounce_addr);
+
+err2:
+	kfree(dwc->setup_buf);
+
+err1:
+	dma_free_coherent(dwc->sysdev, sizeof(*dwc->ep0_trb) * 2,
+			dwc->ep0_trb, dwc->ep0_trb_addr);
+
+err0:
+	return ret;
+}
+
+/* -------------------------------------------------------------------------- */
+
+void dwc3_gadget_exit(struct dwc3 *dwc)
+{
+	usb_del_gadget_udc(&dwc->gadget);
+	dwc3_gadget_free_endpoints(dwc);
+	dma_free_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE, dwc->bounce,
+			  dwc->bounce_addr);
+	kfree(dwc->setup_buf);
+	dma_free_coherent(dwc->sysdev, sizeof(*dwc->ep0_trb) * 2,
+			  dwc->ep0_trb, dwc->ep0_trb_addr);
+}
+
+int dwc3_gadget_suspend(struct dwc3 *dwc)
+{
+	if (!dwc->gadget_driver)
+		return 0;
+
+	dwc3_gadget_run_stop(dwc, false, false);
+	dwc3_disconnect_gadget(dwc);
+	__dwc3_gadget_stop(dwc);
+
+	synchronize_irq(dwc->irq_gadget);
+
+	return 0;
+}
+
+int dwc3_gadget_resume(struct dwc3 *dwc)
+{
+	int			ret;
+
+	if (!dwc->gadget_driver)
+		return 0;
+
+	ret = __dwc3_gadget_start(dwc);
+	if (ret < 0)
+		goto err0;
+
+	ret = dwc3_gadget_run_stop(dwc, true, false);
+	if (ret < 0)
+		goto err1;
+
+	return 0;
+
+err1:
+	__dwc3_gadget_stop(dwc);
+
+err0:
+	return ret;
+}
+
+void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
+{
+	if (dwc->pending_events) {
+		dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
+		dwc->pending_events = false;
+		enable_irq(dwc->irq_gadget);
+	}
+}