usb: Add MediaTek USB3 DRD driver

This patch adds support for the MediaTek USB3 controller
integrated into MT8173. It currently supports High-Speed
Peripheral Only mode.

Super-Speed Peripheral, Dual-Role Device and Host Only (xHCI)
modes will be added in the next patchs.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 709 insertions, 0 deletions

diff --git a/drivers/usb/mtu3/mtu3_gadget.c b/drivers/usb/mtu3/mtu3_gadget.c
new file mode 100644
index 000000000000..0e25e0f9e605
--- /dev/null
+++ b/drivers/usb/mtu3/mtu3_gadget.c
@@ -0,0 +1,709 @@
+/*
+ * mtu3_gadget.c - MediaTek usb3 DRD peripheral support
+ *
+ * Copyright (C) 2016 MediaTek Inc.
+ *
+ * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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 "mtu3.h"
+
+void mtu3_req_complete(struct mtu3_ep *mep,
+		     struct usb_request *req, int status)
+__releases(mep->mtu->lock)
+__acquires(mep->mtu->lock)
+{
+	struct mtu3_request *mreq;
+	struct mtu3 *mtu;
+	int busy = mep->busy;
+
+	mreq = to_mtu3_request(req);
+	list_del(&mreq->list);
+	if (mreq->request.status == -EINPROGRESS)
+		mreq->request.status = status;
+
+	mtu = mreq->mtu;
+	mep->busy = 1;
+	spin_unlock(&mtu->lock);
+
+	/* ep0 makes use of PIO, needn't unmap it */
+	if (mep->epnum)
+		usb_gadget_unmap_request(&mtu->g, req, mep->is_in);
+
+	dev_dbg(mtu->dev, "%s complete req: %p, sts %d, %d/%d\n", mep->name,
+		req, req->status, mreq->request.actual, mreq->request.length);
+
+	usb_gadget_giveback_request(&mep->ep, &mreq->request);
+
+	spin_lock(&mtu->lock);
+	mep->busy = busy;
+}
+
+static void nuke(struct mtu3_ep *mep, const int status)
+{
+	struct mtu3_request *mreq = NULL;
+
+	mep->busy = 1;
+	if (list_empty(&mep->req_list))
+		return;
+
+	dev_dbg(mep->mtu->dev, "abort %s's req: sts %d\n", mep->name, status);
+
+	/* exclude EP0 */
+	if (mep->epnum)
+		mtu3_qmu_flush(mep);
+
+	while (!list_empty(&mep->req_list)) {
+		mreq = list_first_entry(&mep->req_list,
+					struct mtu3_request, list);
+		mtu3_req_complete(mep, &mreq->request, status);
+	}
+}
+
+static int mtu3_ep_enable(struct mtu3_ep *mep)
+{
+	const struct usb_endpoint_descriptor *desc;
+	struct mtu3 *mtu = mep->mtu;
+	u32 interval = 0;
+	u32 mult = 0;
+	u32 burst = 0;
+	int max_packet;
+	int ret;
+
+	desc = mep->desc;
+	mep->type = usb_endpoint_type(desc);
+	max_packet = usb_endpoint_maxp(desc);
+	mep->maxp = max_packet & GENMASK(10, 0);
+
+	switch (mtu->g.speed) {
+	case USB_SPEED_HIGH:
+		if (usb_endpoint_xfer_isoc(desc) ||
+				usb_endpoint_xfer_int(desc)) {
+			interval = desc->bInterval;
+			interval = clamp_val(interval, 1, 16) - 1;
+			burst = (max_packet & GENMASK(12, 11)) >> 11;
+		}
+		break;
+	default:
+		break; /*others are ignored */
+	}
+
+	dev_dbg(mtu->dev, "%s maxp:%d, interval:%d, burst:%d, mult:%d\n",
+		__func__, mep->maxp, interval, burst, mult);
+
+	mep->ep.maxpacket = mep->maxp;
+	mep->ep.desc = desc;
+
+	/* slot mainly affects bulk/isoc transfer, so ignore int */
+	mep->slot = usb_endpoint_xfer_int(desc) ? 0 : mtu->slot;
+
+	ret = mtu3_config_ep(mtu, mep, interval, burst, mult);
+	if (ret < 0)
+		return ret;
+
+	ret = mtu3_gpd_ring_alloc(mep);
+	if (ret < 0) {
+		mtu3_deconfig_ep(mtu, mep);
+		return ret;
+	}
+
+	mtu3_qmu_start(mep);
+
+	return 0;
+}
+
+static int mtu3_ep_disable(struct mtu3_ep *mep)
+{
+	struct mtu3 *mtu = mep->mtu;
+
+	mtu3_qmu_stop(mep);
+
+	/* abort all pending requests */
+	nuke(mep, -ESHUTDOWN);
+	mtu3_deconfig_ep(mtu, mep);
+	mtu3_gpd_ring_free(mep);
+
+	mep->desc = NULL;
+	mep->ep.desc = NULL;
+	mep->type = 0;
+	mep->flags = 0;
+
+	return 0;
+}
+
+static int mtu3_gadget_ep_enable(struct usb_ep *ep,
+		const struct usb_endpoint_descriptor *desc)
+{
+	struct mtu3_ep *mep;
+	struct mtu3 *mtu;
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
+		pr_debug("%s invalid parameters\n", __func__);
+		return -EINVAL;
+	}
+
+	if (!desc->wMaxPacketSize) {
+		pr_debug("%s missing wMaxPacketSize\n", __func__);
+		return -EINVAL;
+	}
+	mep = to_mtu3_ep(ep);
+	mtu = mep->mtu;
+
+	/* check ep number and direction against endpoint */
+	if (usb_endpoint_num(desc) != mep->epnum)
+		return -EINVAL;
+
+	if (!!usb_endpoint_dir_in(desc) ^ !!mep->is_in)
+		return -EINVAL;
+
+	dev_dbg(mtu->dev, "%s %s\n", __func__, ep->name);
+
+	if (mep->flags & MTU3_EP_ENABLED) {
+		dev_WARN_ONCE(mtu->dev, true, "%s is already enabled\n",
+				mep->name);
+		return 0;
+	}
+
+	spin_lock_irqsave(&mtu->lock, flags);
+	mep->desc = desc;
+
+	ret = mtu3_ep_enable(mep);
+	if (ret)
+		goto error;
+
+	mep->busy = 0;
+	mep->wedged = 0;
+	mep->flags |= MTU3_EP_ENABLED;
+	mtu->active_ep++;
+
+error:
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	dev_dbg(mtu->dev, "%s active_ep=%d\n", __func__, mtu->active_ep);
+
+	return ret;
+}
+
+static int mtu3_gadget_ep_disable(struct usb_ep *ep)
+{
+	struct mtu3_ep *mep = to_mtu3_ep(ep);
+	struct mtu3 *mtu = mep->mtu;
+	unsigned long flags;
+
+	dev_dbg(mtu->dev, "%s %s\n", __func__, mep->name);
+
+	if (!(mep->flags & MTU3_EP_ENABLED)) {
+		dev_warn(mtu->dev, "%s is already disabled\n", mep->name);
+		return 0;
+	}
+
+	spin_lock_irqsave(&mtu->lock, flags);
+	mtu3_ep_disable(mep);
+	mep->flags &= ~MTU3_EP_ENABLED;
+	mtu->active_ep--;
+	spin_unlock_irqrestore(&(mtu->lock), flags);
+
+	dev_dbg(mtu->dev, "%s active_ep=%d, mtu3 is_active=%d\n",
+		__func__, mtu->active_ep, mtu->is_active);
+
+	return 0;
+}
+
+struct usb_request *mtu3_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
+{
+	struct mtu3_ep *mep = to_mtu3_ep(ep);
+	struct mtu3_request *mreq;
+
+	mreq = kzalloc(sizeof(*mreq), gfp_flags);
+	if (!mreq)
+		return NULL;
+
+	mreq->request.dma = DMA_ADDR_INVALID;
+	mreq->epnum = mep->epnum;
+	mreq->mep = mep;
+
+	return &mreq->request;
+}
+
+void mtu3_free_request(struct usb_ep *ep, struct usb_request *req)
+{
+	kfree(to_mtu3_request(req));
+}
+
+static int mtu3_gadget_queue(struct usb_ep *ep,
+		struct usb_request *req, gfp_t gfp_flags)
+{
+	struct mtu3_ep *mep;
+	struct mtu3_request *mreq;
+	struct mtu3 *mtu;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!ep || !req)
+		return -EINVAL;
+
+	if (!req->buf)
+		return -ENODATA;
+
+	mep = to_mtu3_ep(ep);
+	mtu = mep->mtu;
+	mreq = to_mtu3_request(req);
+	mreq->mtu = mtu;
+
+	if (mreq->mep != mep)
+		return -EINVAL;
+
+	dev_dbg(mtu->dev, "%s %s EP%d(%s), req=%p, maxp=%d, len#%d\n",
+		__func__, mep->is_in ? "TX" : "RX", mreq->epnum, ep->name,
+		mreq, ep->maxpacket, mreq->request.length);
+
+	if (req->length > GPD_BUF_SIZE) {
+		dev_warn(mtu->dev,
+			"req length > supported MAX:%d requested:%d\n",
+			GPD_BUF_SIZE, req->length);
+		return -EOPNOTSUPP;
+	}
+
+	/* don't queue if the ep is down */
+	if (!mep->desc) {
+		dev_dbg(mtu->dev, "req=%p queued to %s while it's disabled\n",
+			req, ep->name);
+		return -ESHUTDOWN;
+	}
+
+	mreq->request.actual = 0;
+	mreq->request.status = -EINPROGRESS;
+
+	ret = usb_gadget_map_request(&mtu->g, req, mep->is_in);
+	if (ret) {
+		dev_err(mtu->dev, "dma mapping failed\n");
+		return ret;
+	}
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	if (mtu3_prepare_transfer(mep)) {
+		ret = -EAGAIN;
+		goto error;
+	}
+
+	list_add_tail(&mreq->list, &mep->req_list);
+	mtu3_insert_gpd(mep, mreq);
+	mtu3_qmu_resume(mep);
+
+error:
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return ret;
+}
+
+static int mtu3_gadget_dequeue(struct usb_ep *ep, struct usb_request *req)
+{
+	struct mtu3_ep *mep = to_mtu3_ep(ep);
+	struct mtu3_request *mreq = to_mtu3_request(req);
+	struct mtu3_request *r;
+	unsigned long flags;
+	int ret = 0;
+	struct mtu3 *mtu = mep->mtu;
+
+	if (!ep || !req || mreq->mep != mep)
+		return -EINVAL;
+
+	dev_dbg(mtu->dev, "%s : req=%p\n", __func__, req);
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	list_for_each_entry(r, &mep->req_list, list) {
+		if (r == mreq)
+			break;
+	}
+	if (r != mreq) {
+		dev_dbg(mtu->dev, "req=%p not queued to %s\n", req, ep->name);
+		ret = -EINVAL;
+		goto done;
+	}
+
+	mtu3_qmu_flush(mep);  /* REVISIT: set BPS ?? */
+	mtu3_req_complete(mep, req, -ECONNRESET);
+	mtu3_qmu_start(mep);
+
+done:
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return ret;
+}
+
+/*
+ * Set or clear the halt bit of an EP.
+ * A halted EP won't TX/RX any data but will queue requests.
+ */
+static int mtu3_gadget_ep_set_halt(struct usb_ep *ep, int value)
+{
+	struct mtu3_ep *mep = to_mtu3_ep(ep);
+	struct mtu3 *mtu = mep->mtu;
+	struct mtu3_request *mreq;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!ep)
+		return -EINVAL;
+
+	dev_dbg(mtu->dev, "%s : %s...", __func__, ep->name);
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	if (mep->type == USB_ENDPOINT_XFER_ISOC) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	mreq = next_request(mep);
+	if (value) {
+		/*
+		 * If there is not request for TX-EP, QMU will not transfer
+		 * data to TX-FIFO, so no need check whether TX-FIFO
+		 * holds bytes or not here
+		 */
+		if (mreq) {
+			dev_dbg(mtu->dev, "req in progress, cannot halt %s\n",
+				ep->name);
+			ret = -EAGAIN;
+			goto done;
+		}
+	} else {
+		mep->wedged = 0;
+	}
+
+	dev_dbg(mtu->dev, "%s %s stall\n", ep->name, value ? "set" : "clear");
+
+	mtu3_ep_stall_set(mep, value);
+
+done:
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return ret;
+}
+
+/* Sets the halt feature with the clear requests ignored */
+static int mtu3_gadget_ep_set_wedge(struct usb_ep *ep)
+{
+	struct mtu3_ep *mep = to_mtu3_ep(ep);
+
+	if (!ep)
+		return -EINVAL;
+
+	mep->wedged = 1;
+
+	return usb_ep_set_halt(ep);
+}
+
+static const struct usb_ep_ops mtu3_ep_ops = {
+	.enable = mtu3_gadget_ep_enable,
+	.disable = mtu3_gadget_ep_disable,
+	.alloc_request = mtu3_alloc_request,
+	.free_request = mtu3_free_request,
+	.queue = mtu3_gadget_queue,
+	.dequeue = mtu3_gadget_dequeue,
+	.set_halt = mtu3_gadget_ep_set_halt,
+	.set_wedge = mtu3_gadget_ep_set_wedge,
+};
+
+static int mtu3_gadget_get_frame(struct usb_gadget *gadget)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(gadget);
+
+	return (int)mtu3_readl(mtu->mac_base, U3D_USB20_FRAME_NUM);
+}
+
+static int mtu3_gadget_wakeup(struct usb_gadget *gadget)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(gadget);
+	unsigned long flags;
+
+	dev_dbg(mtu->dev, "%s\n", __func__);
+
+	/* remote wakeup feature is not enabled by host */
+	if (!mtu->may_wakeup)
+		return  -EOPNOTSUPP;
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	mtu3_setbits(mtu->mac_base, U3D_POWER_MANAGEMENT, RESUME);
+	spin_unlock_irqrestore(&mtu->lock, flags);
+	usleep_range(10000, 11000);
+	spin_lock_irqsave(&mtu->lock, flags);
+	mtu3_clrbits(mtu->mac_base, U3D_POWER_MANAGEMENT, RESUME);
+
+	spin_unlock_irqrestore(&mtu->lock, flags);
+	return 0;
+}
+
+static int mtu3_gadget_set_self_powered(struct usb_gadget *gadget,
+		int is_selfpowered)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(gadget);
+
+	mtu->is_self_powered = !!is_selfpowered;
+	return 0;
+}
+
+static int mtu3_gadget_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(gadget);
+	unsigned long flags;
+
+	dev_dbg(mtu->dev, "%s (%s) for %sactive device\n", __func__,
+		is_on ? "on" : "off", mtu->is_active ? "" : "in");
+
+	/* we'd rather not pullup unless the device is active. */
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	is_on = !!is_on;
+	if (!mtu->is_active) {
+		/* save it for mtu3_start() to process the request */
+		mtu->softconnect = is_on;
+	} else if (is_on != mtu->softconnect) {
+		mtu->softconnect = is_on;
+		mtu3_hs_softconn_set(mtu, is_on);
+	}
+
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return 0;
+}
+
+static int mtu3_gadget_start(struct usb_gadget *gadget,
+		struct usb_gadget_driver *driver)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(gadget);
+	unsigned long flags;
+
+	if (mtu->gadget_driver) {
+		dev_err(mtu->dev, "%s is already bound to %s\n",
+			mtu->g.name, mtu->gadget_driver->driver.name);
+		return -EBUSY;
+	}
+
+	dev_dbg(mtu->dev, "bind driver %s\n", driver->function);
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	mtu->softconnect = 0;
+	mtu->gadget_driver = driver;
+
+	mtu3_start(mtu);
+
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return 0;
+}
+
+static void stop_activity(struct mtu3 *mtu)
+{
+	struct usb_gadget_driver *driver = mtu->gadget_driver;
+	int i;
+
+	/* don't disconnect if it's not connected */
+	if (mtu->g.speed == USB_SPEED_UNKNOWN)
+		driver = NULL;
+	else
+		mtu->g.speed = USB_SPEED_UNKNOWN;
+
+	/* deactivate the hardware */
+	if (mtu->softconnect) {
+		mtu->softconnect = 0;
+		mtu3_hs_softconn_set(mtu, 0);
+	}
+
+	/*
+	 * killing any outstanding requests will quiesce the driver;
+	 * then report disconnect
+	 */
+	nuke(mtu->ep0, -ESHUTDOWN);
+	for (i = 1; i < mtu->num_eps; i++) {
+		nuke(mtu->in_eps + i, -ESHUTDOWN);
+		nuke(mtu->out_eps + i, -ESHUTDOWN);
+	}
+
+	if (driver) {
+		spin_unlock(&mtu->lock);
+		driver->disconnect(&mtu->g);
+		spin_lock(&mtu->lock);
+	}
+}
+
+static int mtu3_gadget_stop(struct usb_gadget *g)
+{
+	struct mtu3 *mtu = gadget_to_mtu3(g);
+	unsigned long flags;
+
+	dev_dbg(mtu->dev, "%s\n", __func__);
+
+	spin_lock_irqsave(&mtu->lock, flags);
+
+	stop_activity(mtu);
+	mtu->gadget_driver = NULL;
+
+	mtu3_stop(mtu);
+
+	spin_unlock_irqrestore(&mtu->lock, flags);
+
+	return 0;
+}
+
+static const struct usb_gadget_ops mtu3_gadget_ops = {
+	.get_frame = mtu3_gadget_get_frame,
+	.wakeup = mtu3_gadget_wakeup,
+	.set_selfpowered = mtu3_gadget_set_self_powered,
+	.pullup = mtu3_gadget_pullup,
+	.udc_start = mtu3_gadget_start,
+	.udc_stop = mtu3_gadget_stop,
+};
+
+static void init_hw_ep(struct mtu3 *mtu, struct mtu3_ep *mep,
+		u32 epnum, u32 is_in)
+{
+	mep->epnum = epnum;
+	mep->mtu = mtu;
+	mep->is_in = is_in;
+
+	INIT_LIST_HEAD(&mep->req_list);
+
+	sprintf(mep->name, "ep%d%s", epnum,
+		!epnum ? "" : (is_in ? "in" : "out"));
+
+	mep->ep.name = mep->name;
+	INIT_LIST_HEAD(&mep->ep.ep_list);
+
+	/* initialize maxpacket as HS */
+	if (!epnum) {
+		usb_ep_set_maxpacket_limit(&mep->ep, 64);
+		mep->ep.caps.type_control = true;
+		mep->ep.ops = &mtu3_ep0_ops;
+		mtu->g.ep0 = &mep->ep;
+	} else {
+		usb_ep_set_maxpacket_limit(&mep->ep, 512);
+		mep->ep.caps.type_iso = true;
+		mep->ep.caps.type_bulk = true;
+		mep->ep.caps.type_int = true;
+		mep->ep.ops = &mtu3_ep_ops;
+		list_add_tail(&mep->ep.ep_list, &mtu->g.ep_list);
+	}
+
+	dev_dbg(mtu->dev, "%s, name=%s, maxp=%d\n", __func__, mep->ep.name,
+		 mep->ep.maxpacket);
+
+	if (!epnum) {
+		mep->ep.caps.dir_in = true;
+		mep->ep.caps.dir_out = true;
+	} else if (is_in) {
+		mep->ep.caps.dir_in = true;
+	} else {
+		mep->ep.caps.dir_out = true;
+	}
+}
+
+static void mtu3_gadget_init_eps(struct mtu3 *mtu)
+{
+	u8 epnum;
+
+	/* initialize endpoint list just once */
+	INIT_LIST_HEAD(&(mtu->g.ep_list));
+
+	dev_dbg(mtu->dev, "%s num_eps(1 for a pair of tx&rx ep)=%d\n",
+		__func__, mtu->num_eps);
+
+	init_hw_ep(mtu, mtu->ep0, 0, 0);
+	for (epnum = 1; epnum < mtu->num_eps; epnum++) {
+		init_hw_ep(mtu, mtu->in_eps + epnum, epnum, 1);
+		init_hw_ep(mtu, mtu->out_eps + epnum, epnum, 0);
+	}
+}
+
+int mtu3_gadget_setup(struct mtu3 *mtu)
+{
+	int ret;
+
+	mtu->g.ops = &mtu3_gadget_ops;
+	mtu->g.max_speed = USB_SPEED_HIGH;
+	mtu->g.speed = USB_SPEED_UNKNOWN;
+	mtu->g.sg_supported = 0;
+	mtu->g.name = MTU3_DRIVER_NAME;
+	mtu->is_active = 0;
+
+	mtu3_gadget_init_eps(mtu);
+
+	ret = usb_add_gadget_udc(mtu->dev, &mtu->g);
+	if (ret) {
+		dev_err(mtu->dev, "failed to register udc\n");
+		return ret;
+	}
+
+	usb_gadget_set_state(&mtu->g, USB_STATE_NOTATTACHED);
+
+	return 0;
+}
+
+void mtu3_gadget_cleanup(struct mtu3 *mtu)
+{
+	usb_del_gadget_udc(&mtu->g);
+}
+
+void mtu3_gadget_resume(struct mtu3 *mtu)
+{
+	dev_dbg(mtu->dev, "gadget RESUME\n");
+	if (mtu->gadget_driver && mtu->gadget_driver->resume) {
+		spin_unlock(&mtu->lock);
+		mtu->gadget_driver->resume(&mtu->g);
+		spin_lock(&mtu->lock);
+	}
+}
+
+/* called when SOF packets stop for 3+ msec or enters U3 */
+void mtu3_gadget_suspend(struct mtu3 *mtu)
+{
+	dev_dbg(mtu->dev, "gadget SUSPEND\n");
+	if (mtu->gadget_driver && mtu->gadget_driver->suspend) {
+		spin_unlock(&mtu->lock);
+		mtu->gadget_driver->suspend(&mtu->g);
+		spin_lock(&mtu->lock);
+	}
+}
+
+/* called when VBUS drops below session threshold, and in other cases */
+void mtu3_gadget_disconnect(struct mtu3 *mtu)
+{
+	dev_dbg(mtu->dev, "gadget DISCONNECT\n");
+	if (mtu->gadget_driver && mtu->gadget_driver->disconnect) {
+		spin_unlock(&mtu->lock);
+		mtu->gadget_driver->disconnect(&mtu->g);
+		spin_lock(&mtu->lock);
+	}
+
+	usb_gadget_set_state(&mtu->g, USB_STATE_NOTATTACHED);
+}
+
+void mtu3_gadget_reset(struct mtu3 *mtu)
+{
+	dev_dbg(mtu->dev, "gadget RESET\n");
+
+	/* report disconnect, if we didn't flush EP state */
+	if (mtu->g.speed != USB_SPEED_UNKNOWN)
+		mtu3_gadget_disconnect(mtu);
+
+	mtu->address = 0;
+	mtu->ep0_state = MU3D_EP0_STATE_SETUP;
+	mtu->may_wakeup = 0;
+}