Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 2396 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
new file mode 100644
index 00000000..5255fe97
--- /dev/null
+++ b/drivers/usb/dwc3/gadget.c
@@ -0,0 +1,2396 @@
+/**
+ * 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>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2, as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#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 "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_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;
+
+	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);
+
+	/* wait for a change in DSTS */
+	while (--retries) {
+		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+
+		if (DWC3_DSTS_USBLNKST(reg) == state)
+			return 0;
+
+		udelay(5);
+	}
+
+	dev_vdbg(dwc->dev, "link state change request timed out\n");
+
+	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 < DWC3_ENDPOINTS_NUM; num++) {
+		struct dwc3_ep	*dep = dwc->eps[num];
+		int		fifo_number = dep->number >> 1;
+		int		mult = 1;
+		int		tmp;
+
+		if (!(dep->number & 1))
+			continue;
+
+		if (!(dep->flags & DWC3_EP_ENABLED))
+			continue;
+
+		if (usb_endpoint_xfer_bulk(dep->desc)
+				|| usb_endpoint_xfer_isoc(dep->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);
+
+		dev_vdbg(dwc->dev, "%s: Fifo Addr %04x Size %d\n",
+				dep->name, last_fifo_depth, fifo_size & 0xffff);
+
+		dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(fifo_number),
+				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;
+
+	if (req->queued) {
+		if (req->request.num_mapped_sgs)
+			dep->busy_slot += req->request.num_mapped_sgs;
+		else
+			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->desc))
+			dep->busy_slot++;
+	}
+	list_del(&req->list);
+	req->trb = NULL;
+
+	if (req->request.status == -EINPROGRESS)
+		req->request.status = status;
+
+	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);
+
+	spin_unlock(&dwc->lock);
+	req->request.complete(&dep->endpoint, &req->request);
+	spin_lock(&dwc->lock);
+}
+
+static const char *dwc3_gadget_ep_cmd_string(u8 cmd)
+{
+	switch (cmd) {
+	case DWC3_DEPCMD_DEPSTARTCFG:
+		return "Start New Configuration";
+	case DWC3_DEPCMD_ENDTRANSFER:
+		return "End Transfer";
+	case DWC3_DEPCMD_UPDATETRANSFER:
+		return "Update Transfer";
+	case DWC3_DEPCMD_STARTTRANSFER:
+		return "Start Transfer";
+	case DWC3_DEPCMD_CLEARSTALL:
+		return "Clear Stall";
+	case DWC3_DEPCMD_SETSTALL:
+		return "Set Stall";
+	case DWC3_DEPCMD_GETSEQNUMBER:
+		return "Get Data Sequence Number";
+	case DWC3_DEPCMD_SETTRANSFRESOURCE:
+		return "Set Endpoint Transfer Resource";
+	case DWC3_DEPCMD_SETEPCONFIG:
+		return "Set Endpoint Configuration";
+	default:
+		return "UNKNOWN command";
+	}
+}
+
+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;
+
+	dev_vdbg(dwc->dev, "%s: cmd '%s' params %08x %08x %08x\n",
+			dep->name,
+			dwc3_gadget_ep_cmd_string(cmd), params->param0,
+			params->param1, params->param2);
+
+	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)) {
+			dev_vdbg(dwc->dev, "Command Complete --> %d\n",
+					DWC3_DEPCMD_STATUS(reg));
+			return 0;
+		}
+
+		/*
+		 * We can't sleep here, because it is also called from
+		 * interrupt context.
+		 */
+		timeout--;
+		if (!timeout)
+			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;
+
+	if (dep->number == 0 || dep->number == 1)
+		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_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
+{
+	struct dwc3_gadget_ep_cmd_params params;
+	u32			cmd;
+
+	memset(&params, 0x00, sizeof(params));
+
+	if (dep->number != 1) {
+		cmd = DWC3_DEPCMD_DEPSTARTCFG;
+		/* XferRscIdx == 0 for ep0 and 2 for the remaining */
+		if (dep->number > 1) {
+			if (dwc->start_config_issued)
+				return 0;
+			dwc->start_config_issued = true;
+			cmd |= DWC3_DEPCMD_PARAM(2);
+		}
+
+		return dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
+	}
+
+	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)
+{
+	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))
+		| DWC3_DEPCFG_BURST_SIZE(dep->endpoint.maxburst);
+
+	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_isoc(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)
+{
+	struct dwc3		*dwc = dep->dwc;
+	u32			reg;
+	int			ret = -ENOMEM;
+
+	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);
+	if (ret)
+		return ret;
+
+	if (!(dep->flags & DWC3_EP_ENABLED)) {
+		struct dwc3_trb	*trb_st_hw;
+		struct dwc3_trb	*trb_link;
+
+		ret = dwc3_gadget_set_xfer_resource(dwc, dep);
+		if (ret)
+			return ret;
+
+		dep->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;
+
+		memset(&trb_link, 0, sizeof(trb_link));
+
+		/* 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];
+
+		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;
+	}
+
+	return 0;
+}
+
+static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum);
+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);
+
+	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_remove_requests(dwc, dep);
+
+	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->desc = NULL;
+	dep->endpoint.desc = NULL;
+	dep->comp_desc = NULL;
+	dep->type = 0;
+	dep->flags = 0;
+
+	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;
+
+	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");
+	}
+
+	if (dep->flags & DWC3_EP_ENABLED) {
+		dev_WARN_ONCE(dwc->dev, true, "%s is already enabled\n",
+				dep->name);
+		return 0;
+	}
+
+	dev_vdbg(dwc->dev, "Enabling %s\n", dep->name);
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc);
+	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;
+	}
+
+	snprintf(dep->name, sizeof(dep->name), "ep%d%s",
+			dep->number >> 1,
+			(dep->number & 1) ? "in" : "out");
+
+	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);
+	struct dwc3			*dwc = dep->dwc;
+
+	req = kzalloc(sizeof(*req), gfp_flags);
+	if (!req) {
+		dev_err(dwc->dev, "not enough memory\n");
+		return NULL;
+	}
+
+	req->epnum	= dep->number;
+	req->dep	= dep;
+
+	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);
+
+	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)
+{
+	struct dwc3		*dwc = dep->dwc;
+	struct dwc3_trb		*trb;
+
+	unsigned int		cur_slot;
+
+	dev_vdbg(dwc->dev, "%s: req %p dma %08llx length %d%s%s\n",
+			dep->name, req, (unsigned long long) dma,
+			length, last ? " last" : "",
+			chain ? " chain" : "");
+
+	trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];
+	cur_slot = dep->free_slot;
+	dep->free_slot++;
+
+	/* Skip the LINK-TRB on ISOC */
+	if (((cur_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
+			usb_endpoint_xfer_isoc(dep->desc))
+		return;
+
+	if (!req->trb) {
+		dwc3_gadget_move_request_queued(req);
+		req->trb = trb;
+		req->trb_dma = dwc3_trb_dma_offset(dep, trb);
+	}
+
+	trb->size = DWC3_TRB_SIZE_LENGTH(length);
+	trb->bpl = lower_32_bits(dma);
+	trb->bph = upper_32_bits(dma);
+
+	switch (usb_endpoint_type(dep->desc)) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
+		break;
+
+	case USB_ENDPOINT_XFER_ISOC:
+		trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
+
+		/* IOC every DWC3_TRB_NUM / 4 so we can refill */
+		if (!(cur_slot % (DWC3_TRB_NUM / 4)))
+			trb->ctrl |= DWC3_TRB_CTRL_IOC;
+		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 (usb_endpoint_xfer_isoc(dep->desc)) {
+		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
+		trb->ctrl |= DWC3_TRB_CTRL_CSP;
+	} else {
+		if (chain)
+			trb->ctrl |= DWC3_TRB_CTRL_CHN;
+
+		if (last)
+			trb->ctrl |= DWC3_TRB_CTRL_LST;
+	}
+
+	if (usb_endpoint_xfer_bulk(dep->desc) && dep->stream_capable)
+		trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
+
+	trb->ctrl |= DWC3_TRB_CTRL_HWO;
+}
+
+/*
+ * 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->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->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->desc))
+		return;
+
+	list_for_each_entry_safe(req, n, &dep->request_list, list) {
+		unsigned	length;
+		dma_addr_t	dma;
+
+		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)) {
+					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);
+
+				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;
+
+			dwc3_prepare_one_trb(dep, req, dma, length,
+					last_one, false);
+
+			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;
+
+	if (start_new && (dep->flags & DWC3_EP_BUSY)) {
+		dev_vdbg(dwc->dev, "%s: endpoint busy\n", dep->name);
+		return -EBUSY;
+	}
+	dep->flags &= ~DWC3_EP_PENDING_REQUEST;
+
+	/*
+	 * 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;
+	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;
+	dep->res_trans_idx = dwc3_gadget_ep_get_transfer_index(dwc,
+			dep->number);
+
+	WARN_ON_ONCE(!dep->res_trans_idx);
+
+	return 0;
+}
+
+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;
+
+	/*
+	 * 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);
+
+	/*
+	 * There is one special case: 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) {
+		int ret;
+		int start_trans;
+
+		start_trans = 1;
+		if (usb_endpoint_xfer_isoc(dep->desc) &&
+				(dep->flags & DWC3_EP_BUSY))
+			start_trans = 0;
+
+		ret = __dwc3_gadget_kick_transfer(dep, 0, start_trans);
+		if (ret && ret != -EBUSY) {
+			struct dwc3	*dwc = dep->dwc;
+
+			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
+					dep->name);
+		}
+	};
+
+	return 0;
+}
+
+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;
+
+	if (!dep->desc) {
+		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
+				request, ep->name);
+		return -ESHUTDOWN;
+	}
+
+	dev_vdbg(dwc->dev, "queing request %p to %s length %d\n",
+			request, ep->name, request->length);
+
+	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;
+
+	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);
+			goto out0;
+		}
+		dev_err(dwc->dev, "request %p was not queued to %s\n",
+				request, ep->name);
+		ret = -EINVAL;
+		goto out0;
+	}
+
+	/* 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)
+{
+	struct dwc3_gadget_ep_cmd_params	params;
+	struct dwc3				*dwc = dep->dwc;
+	int					ret;
+
+	memset(&params, 0x00, sizeof(params));
+
+	if (value) {
+		if (dep->number == 0 || dep->number == 1) {
+			/*
+			 * Whenever EP0 is stalled, we will restart
+			 * the state machine, thus moving back to
+			 * Setup Phase
+			 */
+			dwc->ep0state = EP0_SETUP_PHASE;
+		}
+
+		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
+			DWC3_DEPCMD_SETSTALL, &params);
+		if (ret)
+			dev_err(dwc->dev, "failed to %s STALL on %s\n",
+					value ? "set" : "clear",
+					dep->name);
+		else
+			dep->flags |= DWC3_EP_STALL;
+	} else {
+		if (dep->flags & DWC3_EP_WEDGE)
+			return 0;
+
+		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
+			DWC3_DEPCMD_CLEARSTALL, &params);
+		if (ret)
+			dev_err(dwc->dev, "failed to %s STALL on %s\n",
+					value ? "set" : "clear",
+					dep->name);
+		else
+			dep->flags &= ~DWC3_EP_STALL;
+	}
+
+	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);
+
+	if (usb_endpoint_xfer_isoc(dep->desc)) {
+		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = __dwc3_gadget_ep_set_halt(dep, value);
+out:
+	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;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	dep->flags |= DWC3_EP_WEDGE;
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return dwc3_gadget_ep_set_halt(ep, 1);
+}
+
+/* -------------------------------------------------------------------------- */
+
+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_ep_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;
+	}
+
+	/* write zeroes to Link Change Request */
+	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);
+	dwc->is_selfpowered = !!is_selfpowered;
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return 0;
+}
+
+static void dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on)
+{
+	u32			reg;
+	u32			timeout = 500;
+
+	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+	if (is_on) {
+		reg &= ~DWC3_DCTL_TRGTULST_MASK;
+		reg |= (DWC3_DCTL_RUN_STOP
+				| DWC3_DCTL_TRGTULST_RX_DET);
+	} else {
+		reg &= ~DWC3_DCTL_RUN_STOP;
+	}
+
+	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)
+			break;
+		udelay(1);
+	} while (1);
+
+	dev_vdbg(dwc->dev, "gadget %s data soft-%s\n",
+			dwc->gadget_driver
+			? dwc->gadget_driver->function : "no-function",
+			is_on ? "connect" : "disconnect");
+}
+
+static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+
+	is_on = !!is_on;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+	dwc3_gadget_run_stop(dwc, is_on);
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return 0;
+}
+
+static int dwc3_gadget_start(struct usb_gadget *g,
+		struct usb_gadget_driver *driver)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	struct dwc3_ep		*dep;
+	unsigned long		flags;
+	int			ret = 0;
+	u32			reg;
+
+	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 err0;
+	}
+
+	dwc->gadget_driver	= driver;
+	dwc->gadget.dev.driver	= &driver->driver;
+
+	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
+	reg &= ~(DWC3_DCFG_SPEED_MASK);
+	reg |= dwc->maximum_speed;
+	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+
+	dwc->start_config_issued = false;
+
+	/* 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);
+	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);
+	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);
+
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return 0;
+
+err1:
+	__dwc3_gadget_ep_disable(dwc->eps[0]);
+
+err0:
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return ret;
+}
+
+static int dwc3_gadget_stop(struct usb_gadget *g,
+		struct usb_gadget_driver *driver)
+{
+	struct dwc3		*dwc = gadget_to_dwc(g);
+	unsigned long		flags;
+
+	spin_lock_irqsave(&dwc->lock, flags);
+
+	__dwc3_gadget_ep_disable(dwc->eps[0]);
+	__dwc3_gadget_ep_disable(dwc->eps[1]);
+
+	dwc->gadget_driver	= NULL;
+	dwc->gadget.dev.driver	= NULL;
+
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	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,
+	.pullup			= dwc3_gadget_pullup,
+	.udc_start		= dwc3_gadget_start,
+	.udc_stop		= dwc3_gadget_stop,
+};
+
+/* -------------------------------------------------------------------------- */
+
+static int __devinit dwc3_gadget_init_endpoints(struct dwc3 *dwc)
+{
+	struct dwc3_ep			*dep;
+	u8				epnum;
+
+	INIT_LIST_HEAD(&dwc->gadget.ep_list);
+
+	for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
+		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+		if (!dep) {
+			dev_err(dwc->dev, "can't allocate endpoint %d\n",
+					epnum);
+			return -ENOMEM;
+		}
+
+		dep->dwc = dwc;
+		dep->number = epnum;
+		dwc->eps[epnum] = dep;
+
+		snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
+				(epnum & 1) ? "in" : "out");
+		dep->endpoint.name = dep->name;
+		dep->direction = (epnum & 1);
+
+		if (epnum == 0 || epnum == 1) {
+			dep->endpoint.maxpacket = 512;
+			dep->endpoint.ops = &dwc3_gadget_ep0_ops;
+			if (!epnum)
+				dwc->gadget.ep0 = &dep->endpoint;
+		} else {
+			int		ret;
+
+			dep->endpoint.maxpacket = 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;
+		}
+
+		INIT_LIST_HEAD(&dep->request_list);
+		INIT_LIST_HEAD(&dep->req_queued);
+	}
+
+	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];
+		dwc3_free_trb_pool(dep);
+
+		if (epnum != 0 && epnum != 1)
+			list_del(&dep->endpoint.ep_list);
+
+		kfree(dep);
+	}
+}
+
+static void dwc3_gadget_release(struct device *dev)
+{
+	dev_dbg(dev, "%s\n", __func__);
+}
+
+/* -------------------------------------------------------------------------- */
+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		count;
+	unsigned int		s_pkt = 0;
+
+	do {
+		req = next_request(&dep->req_queued);
+		if (!req) {
+			WARN_ON_ONCE(1);
+			return 1;
+		}
+
+		trb = req->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 (%p) still owned by HW\n",
+					dep->name, req->trb);
+		count = trb->size & DWC3_TRB_SIZE_MASK;
+
+		if (dep->direction) {
+			if (count) {
+				dev_err(dwc->dev, "incomplete IN transfer %s\n",
+						dep->name);
+				status = -ECONNRESET;
+			}
+		} else {
+			if (count && (event->status & DEPEVT_STATUS_SHORT))
+				s_pkt = 1;
+		}
+
+		/*
+		 * 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 (s_pkt)
+			break;
+		if ((event->status & DEPEVT_STATUS_LST) &&
+				(trb->ctrl & DWC3_TRB_CTRL_LST))
+			break;
+		if ((event->status & DEPEVT_STATUS_IOC) &&
+				(trb->ctrl & DWC3_TRB_CTRL_IOC))
+			break;
+	} while (1);
+
+	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,
+		int start_new)
+{
+	unsigned		status = 0;
+	int			clean_busy;
+
+	if (event->status & DEPEVT_STATUS_BUSERR)
+		status = -ECONNRESET;
+
+	clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
+	if (clean_busy)
+		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++) {
+			struct dwc3_ep	*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;
+	}
+}
+
+static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
+		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
+{
+	u32 uf, mask;
+
+	if (list_empty(&dep->request_list)) {
+		dev_vdbg(dwc->dev, "ISOC ep %s run out for requests.\n",
+			dep->name);
+		return;
+	}
+
+	mask = ~(dep->interval - 1);
+	uf = event->parameters & mask;
+	/* 4 micro frames in the future */
+	uf += dep->interval * 4;
+
+	__dwc3_gadget_kick_transfer(dep, uf, 1);
+}
+
+static void dwc3_process_ep_cmd_complete(struct dwc3_ep *dep,
+		const struct dwc3_event_depevt *event)
+{
+	struct dwc3 *dwc = dep->dwc;
+	struct dwc3_event_depevt mod_ev = *event;
+
+	/*
+	 * We were asked to remove one request. It is possible that this
+	 * request and a few others were started together and have the same
+	 * transfer index. Since we stopped the complete endpoint we don't
+	 * know how many requests were already completed (and not yet)
+	 * reported and how could be done (later). We purge them all until
+	 * the end of the list.
+	 */
+	mod_ev.status = DEPEVT_STATUS_LST;
+	dwc3_cleanup_done_reqs(dwc, dep, &mod_ev, -ESHUTDOWN);
+	dep->flags &= ~DWC3_EP_BUSY;
+	/* pending requests are ignored and are queued on XferNotReady */
+}
+
+static void dwc3_ep_cmd_compl(struct dwc3_ep *dep,
+		const struct dwc3_event_depevt *event)
+{
+	u32 param = event->parameters;
+	u32 cmd_type = (param >> 8) & ((1 << 5) - 1);
+
+	switch (cmd_type) {
+	case DWC3_DEPCMD_ENDTRANSFER:
+		dwc3_process_ep_cmd_complete(dep, event);
+		break;
+	case DWC3_DEPCMD_STARTTRANSFER:
+		dep->res_trans_idx = param & 0x7f;
+		break;
+	default:
+		printk(KERN_ERR "%s() unknown /unexpected type: %d\n",
+				__func__, cmd_type);
+		break;
+	};
+}
+
+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];
+
+	dev_vdbg(dwc->dev, "%s: %s\n", dep->name,
+			dwc3_ep_event_string(event->endpoint_event));
+
+	if (epnum == 0 || epnum == 1) {
+		dwc3_ep0_interrupt(dwc, event);
+		return;
+	}
+
+	switch (event->endpoint_event) {
+	case DWC3_DEPEVT_XFERCOMPLETE:
+		dep->res_trans_idx = 0;
+
+		if (usb_endpoint_xfer_isoc(dep->desc)) {
+			dev_dbg(dwc->dev, "%s is an Isochronous endpoint\n",
+					dep->name);
+			return;
+		}
+
+		dwc3_endpoint_transfer_complete(dwc, dep, event, 1);
+		break;
+	case DWC3_DEPEVT_XFERINPROGRESS:
+		if (!usb_endpoint_xfer_isoc(dep->desc)) {
+			dev_dbg(dwc->dev, "%s is not an Isochronous endpoint\n",
+					dep->name);
+			return;
+		}
+
+		dwc3_endpoint_transfer_complete(dwc, dep, event, 0);
+		break;
+	case DWC3_DEPEVT_XFERNOTREADY:
+		if (usb_endpoint_xfer_isoc(dep->desc)) {
+			dwc3_gadget_start_isoc(dwc, dep, event);
+		} else {
+			int ret;
+
+			dev_vdbg(dwc->dev, "%s: reason %s\n",
+					dep->name, event->status &
+					DEPEVT_STATUS_TRANSFER_ACTIVE
+					? "Transfer Active"
+					: "Transfer Not Active");
+
+			ret = __dwc3_gadget_kick_transfer(dep, 0, 1);
+			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->desc)) {
+			dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
+					dep->name);
+			return;
+		}
+
+		switch (event->status) {
+		case DEPEVT_STREAMEVT_FOUND:
+			dev_vdbg(dwc->dev, "Stream %d found and started\n",
+					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_ep_cmd_compl(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_stop_active_transfer(struct dwc3 *dwc, u32 epnum)
+{
+	struct dwc3_ep *dep;
+	struct dwc3_gadget_ep_cmd_params params;
+	u32 cmd;
+	int ret;
+
+	dep = dwc->eps[epnum];
+
+	WARN_ON(!dep->res_trans_idx);
+	if (dep->res_trans_idx) {
+		cmd = DWC3_DEPCMD_ENDTRANSFER;
+		cmd |= DWC3_DEPCMD_HIPRI_FORCERM | DWC3_DEPCMD_CMDIOC;
+		cmd |= DWC3_DEPCMD_PARAM(dep->res_trans_idx);
+		memset(&params, 0, sizeof(params));
+		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
+		WARN_ON_ONCE(ret);
+		dep->res_trans_idx = 0;
+	}
+}
+
+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->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->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)
+{
+	dev_vdbg(dwc->dev, "%s\n", __func__);
+#if 0
+	XXX
+	U1/U2 is powersave optimization. Skip it for now. Anyway we need to
+	enable it before we can disable it.
+
+	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);
+#endif
+
+	dwc3_stop_active_transfers(dwc);
+	dwc3_disconnect_gadget(dwc);
+	dwc->start_config_issued = false;
+
+	dwc->gadget.speed = USB_SPEED_UNKNOWN;
+	dwc->setup_packet_pending = false;
+}
+
+static void dwc3_gadget_usb3_phy_power(struct dwc3 *dwc, int on)
+{
+	u32			reg;
+
+	reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
+
+	if (on)
+		reg &= ~DWC3_GUSB3PIPECTL_SUSPHY;
+	else
+		reg |= DWC3_GUSB3PIPECTL_SUSPHY;
+
+	dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
+}
+
+static void dwc3_gadget_usb2_phy_power(struct dwc3 *dwc, int on)
+{
+	u32			reg;
+
+	reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+
+	if (on)
+		reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
+	else
+		reg |= DWC3_GUSB2PHYCFG_SUSPHY;
+
+	dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+}
+
+static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
+{
+	u32			reg;
+
+	dev_vdbg(dwc->dev, "%s\n", __func__);
+
+	/*
+	 * 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 */
+	dwc->dev_state = DWC3_DEFAULT_STATE;
+
+	/* Enable PHYs */
+	dwc3_gadget_usb2_phy_power(dwc, true);
+	dwc3_gadget_usb3_phy_power(dwc, true);
+
+	if (dwc->gadget.speed != USB_SPEED_UNKNOWN)
+		dwc3_disconnect_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);
+	dwc->start_config_issued = false;
+
+	/* 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_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
+{
+	u32 reg;
+	u32 usb30_clock = DWC3_GCTL_CLK_BUS;
+
+	/*
+	 * We change the clock only at SS but I dunno why I would want to do
+	 * this. Maybe it becomes part of the power saving plan.
+	 */
+
+	if (speed != DWC3_DSTS_SUPERSPEED)
+		return;
+
+	/*
+	 * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
+	 * each time on Connect Done.
+	 */
+	if (!usb30_clock)
+		return;
+
+	reg = dwc3_readl(dwc->regs, DWC3_GCTL);
+	reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
+	dwc3_writel(dwc->regs, DWC3_GCTL, reg);
+}
+
+static void dwc3_gadget_disable_phy(struct dwc3 *dwc, u8 speed)
+{
+	switch (speed) {
+	case USB_SPEED_SUPER:
+		dwc3_gadget_usb2_phy_power(dwc, false);
+		break;
+	case USB_SPEED_HIGH:
+	case USB_SPEED_FULL:
+	case USB_SPEED_LOW:
+		dwc3_gadget_usb3_phy_power(dwc, false);
+		break;
+	}
+}
+
+static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
+{
+	struct dwc3_gadget_ep_cmd_params params;
+	struct dwc3_ep		*dep;
+	int			ret;
+	u32			reg;
+	u8			speed;
+
+	dev_vdbg(dwc->dev, "%s\n", __func__);
+
+	memset(&params, 0x00, sizeof(params));
+
+	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+	speed = reg & DWC3_DSTS_CONNECTSPD;
+	dwc->speed = speed;
+
+	dwc3_update_ram_clk_sel(dwc, speed);
+
+	switch (speed) {
+	case DWC3_DCFG_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_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;
+	}
+
+	/* Disable unneded PHY */
+	dwc3_gadget_disable_phy(dwc, dwc->gadget.speed);
+
+	dep = dwc->eps[0];
+	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL);
+	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);
+	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)
+{
+	dev_vdbg(dwc->dev, "%s\n", __func__);
+
+	/*
+	 * TODO take core out of low power mode when that's
+	 * implemented.
+	 */
+
+	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;
+
+	/*
+	 * 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;
+			}
+		}
+	}
+
+	dwc->link_state = next;
+
+	dev_vdbg(dwc->dev, "%s link %d\n", __func__, dwc->link_state);
+}
+
+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_LINK_STATUS_CHANGE:
+		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
+		break;
+	case DWC3_DEVICE_EVENT_EOPF:
+		dev_vdbg(dwc->dev, "End of Periodic Frame\n");
+		break;
+	case DWC3_DEVICE_EVENT_SOF:
+		dev_vdbg(dwc->dev, "Start of Periodic Frame\n");
+		break;
+	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
+		dev_vdbg(dwc->dev, "Erratic Error\n");
+		break;
+	case DWC3_DEVICE_EVENT_CMD_CMPL:
+		dev_vdbg(dwc->dev, "Command Complete\n");
+		break;
+	case DWC3_DEVICE_EVENT_OVERFLOW:
+		dev_vdbg(dwc->dev, "Overflow\n");
+		break;
+	default:
+		dev_dbg(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
+	}
+}
+
+static void dwc3_process_event_entry(struct dwc3 *dwc,
+		const union dwc3_event *event)
+{
+	/* 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;
+	int left;
+	u32 count;
+
+	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(buf));
+	count &= DWC3_GEVNTCOUNT_MASK;
+	if (!count)
+		return IRQ_NONE;
+
+	evt = dwc->ev_buffs[buf];
+	left = count;
+
+	while (left > 0) {
+		union dwc3_event event;
+
+		event.raw = *(u32 *) (evt->buf + evt->lpos);
+
+		dwc3_process_event_entry(dwc, &event);
+		/*
+		 * XXX 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 were 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);
+	}
+
+	return IRQ_HANDLED;
+}
+
+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++) {
+		irqreturn_t status;
+
+		status = dwc3_process_event_buf(dwc, i);
+		if (status == IRQ_HANDLED)
+			ret = status;
+	}
+
+	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 __devinit dwc3_gadget_init(struct dwc3 *dwc)
+{
+	u32					reg;
+	int					ret;
+	int					irq;
+
+	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;
+	}
+
+	dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
+			&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(sizeof(*dwc->setup_buf) * 2,
+			GFP_KERNEL);
+	if (!dwc->setup_buf) {
+		dev_err(dwc->dev, "failed to allocate setup buffer\n");
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
+			512, &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;
+	}
+
+	dev_set_name(&dwc->gadget.dev, "gadget");
+
+	dwc->gadget.ops			= &dwc3_gadget_ops;
+	dwc->gadget.max_speed		= USB_SPEED_SUPER;
+	dwc->gadget.speed		= USB_SPEED_UNKNOWN;
+	dwc->gadget.dev.parent		= dwc->dev;
+	dwc->gadget.sg_supported	= true;
+
+	dma_set_coherent_mask(&dwc->gadget.dev, dwc->dev->coherent_dma_mask);
+
+	dwc->gadget.dev.dma_parms	= dwc->dev->dma_parms;
+	dwc->gadget.dev.dma_mask	= dwc->dev->dma_mask;
+	dwc->gadget.dev.release		= dwc3_gadget_release;
+	dwc->gadget.name		= "dwc3-gadget";
+
+	/*
+	 * 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 err4;
+
+	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
+
+	ret = request_irq(irq, dwc3_interrupt, IRQF_SHARED,
+			"dwc3", dwc);
+	if (ret) {
+		dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
+				irq, ret);
+		goto err5;
+	}
+
+	/* 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);
+
+	ret = device_register(&dwc->gadget.dev);
+	if (ret) {
+		dev_err(dwc->dev, "failed to register gadget device\n");
+		put_device(&dwc->gadget.dev);
+		goto err6;
+	}
+
+	ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
+	if (ret) {
+		dev_err(dwc->dev, "failed to register udc\n");
+		goto err7;
+	}
+
+	return 0;
+
+err7:
+	device_unregister(&dwc->gadget.dev);
+
+err6:
+	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
+	free_irq(irq, dwc);
+
+err5:
+	dwc3_gadget_free_endpoints(dwc);
+
+err4:
+	dma_free_coherent(dwc->dev, 512, dwc->ep0_bounce,
+			dwc->ep0_bounce_addr);
+
+err3:
+	kfree(dwc->setup_buf);
+
+err2:
+	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
+			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)
+{
+	int			irq;
+
+	usb_del_gadget_udc(&dwc->gadget);
+	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
+
+	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
+	free_irq(irq, dwc);
+
+	dwc3_gadget_free_endpoints(dwc);
+
+	dma_free_coherent(dwc->dev, 512, dwc->ep0_bounce,
+			dwc->ep0_bounce_addr);
+
+	kfree(dwc->setup_buf);
+
+	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
+			dwc->ep0_trb, dwc->ep0_trb_addr);
+
+	dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
+			dwc->ctrl_req, dwc->ctrl_req_addr);
+
+	device_unregister(&dwc->gadget.dev);
+}