Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 5677 insertions, 0 deletions

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
new file mode 100644
index 000000000..8b15742d9
--- /dev/null
+++ b/drivers/usb/dwc2/gadget.c
@@ -0,0 +1,5677 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * S3C USB2.0 High-speed / OtG driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/mutex.h>
+#include <linux/seq_file.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_platform.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/phy.h>
+#include <linux/usb/composite.h>
+
+
+#include "core.h"
+#include "hw.h"
+
+/* conversion functions */
+static inline struct dwc2_hsotg_req *our_req(struct usb_request *req)
+{
+	return container_of(req, struct dwc2_hsotg_req, req);
+}
+
+static inline struct dwc2_hsotg_ep *our_ep(struct usb_ep *ep)
+{
+	return container_of(ep, struct dwc2_hsotg_ep, ep);
+}
+
+static inline struct dwc2_hsotg *to_hsotg(struct usb_gadget *gadget)
+{
+	return container_of(gadget, struct dwc2_hsotg, gadget);
+}
+
+static inline void dwc2_set_bit(struct dwc2_hsotg *hsotg, u32 offset, u32 val)
+{
+	dwc2_writel(hsotg, dwc2_readl(hsotg, offset) | val, offset);
+}
+
+static inline void dwc2_clear_bit(struct dwc2_hsotg *hsotg, u32 offset, u32 val)
+{
+	dwc2_writel(hsotg, dwc2_readl(hsotg, offset) & ~val, offset);
+}
+
+static inline struct dwc2_hsotg_ep *index_to_ep(struct dwc2_hsotg *hsotg,
+						u32 ep_index, u32 dir_in)
+{
+	if (dir_in)
+		return hsotg->eps_in[ep_index];
+	else
+		return hsotg->eps_out[ep_index];
+}
+
+/* forward declaration of functions */
+static void dwc2_hsotg_dump(struct dwc2_hsotg *hsotg);
+
+/**
+ * using_dma - return the DMA status of the driver.
+ * @hsotg: The driver state.
+ *
+ * Return true if we're using DMA.
+ *
+ * Currently, we have the DMA support code worked into everywhere
+ * that needs it, but the AMBA DMA implementation in the hardware can
+ * only DMA from 32bit aligned addresses. This means that gadgets such
+ * as the CDC Ethernet cannot work as they often pass packets which are
+ * not 32bit aligned.
+ *
+ * Unfortunately the choice to use DMA or not is global to the controller
+ * and seems to be only settable when the controller is being put through
+ * a core reset. This means we either need to fix the gadgets to take
+ * account of DMA alignment, or add bounce buffers (yuerk).
+ *
+ * g_using_dma is set depending on dts flag.
+ */
+static inline bool using_dma(struct dwc2_hsotg *hsotg)
+{
+	return hsotg->params.g_dma;
+}
+
+/*
+ * using_desc_dma - return the descriptor DMA status of the driver.
+ * @hsotg: The driver state.
+ *
+ * Return true if we're using descriptor DMA.
+ */
+static inline bool using_desc_dma(struct dwc2_hsotg *hsotg)
+{
+	return hsotg->params.g_dma_desc;
+}
+
+/**
+ * dwc2_gadget_incr_frame_num - Increments the targeted frame number.
+ * @hs_ep: The endpoint
+ *
+ * This function will also check if the frame number overruns DSTS_SOFFN_LIMIT.
+ * If an overrun occurs it will wrap the value and set the frame_overrun flag.
+ */
+static inline void dwc2_gadget_incr_frame_num(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	u16 limit = DSTS_SOFFN_LIMIT;
+
+	if (hsotg->gadget.speed != USB_SPEED_HIGH)
+		limit >>= 3;
+
+	hs_ep->target_frame += hs_ep->interval;
+	if (hs_ep->target_frame > limit) {
+		hs_ep->frame_overrun = true;
+		hs_ep->target_frame &= limit;
+	} else {
+		hs_ep->frame_overrun = false;
+	}
+}
+
+/**
+ * dwc2_gadget_dec_frame_num_by_one - Decrements the targeted frame number
+ *                                    by one.
+ * @hs_ep: The endpoint.
+ *
+ * This function used in service interval based scheduling flow to calculate
+ * descriptor frame number filed value. For service interval mode frame
+ * number in descriptor should point to last (u)frame in the interval.
+ *
+ */
+static inline void dwc2_gadget_dec_frame_num_by_one(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	u16 limit = DSTS_SOFFN_LIMIT;
+
+	if (hsotg->gadget.speed != USB_SPEED_HIGH)
+		limit >>= 3;
+
+	if (hs_ep->target_frame)
+		hs_ep->target_frame -= 1;
+	else
+		hs_ep->target_frame = limit;
+}
+
+/**
+ * dwc2_hsotg_en_gsint - enable one or more of the general interrupt
+ * @hsotg: The device state
+ * @ints: A bitmask of the interrupts to enable
+ */
+static void dwc2_hsotg_en_gsint(struct dwc2_hsotg *hsotg, u32 ints)
+{
+	u32 gsintmsk = dwc2_readl(hsotg, GINTMSK);
+	u32 new_gsintmsk;
+
+	new_gsintmsk = gsintmsk | ints;
+
+	if (new_gsintmsk != gsintmsk) {
+		dev_dbg(hsotg->dev, "gsintmsk now 0x%08x\n", new_gsintmsk);
+		dwc2_writel(hsotg, new_gsintmsk, GINTMSK);
+	}
+}
+
+/**
+ * dwc2_hsotg_disable_gsint - disable one or more of the general interrupt
+ * @hsotg: The device state
+ * @ints: A bitmask of the interrupts to enable
+ */
+static void dwc2_hsotg_disable_gsint(struct dwc2_hsotg *hsotg, u32 ints)
+{
+	u32 gsintmsk = dwc2_readl(hsotg, GINTMSK);
+	u32 new_gsintmsk;
+
+	new_gsintmsk = gsintmsk & ~ints;
+
+	if (new_gsintmsk != gsintmsk)
+		dwc2_writel(hsotg, new_gsintmsk, GINTMSK);
+}
+
+/**
+ * dwc2_hsotg_ctrl_epint - enable/disable an endpoint irq
+ * @hsotg: The device state
+ * @ep: The endpoint index
+ * @dir_in: True if direction is in.
+ * @en: The enable value, true to enable
+ *
+ * Set or clear the mask for an individual endpoint's interrupt
+ * request.
+ */
+static void dwc2_hsotg_ctrl_epint(struct dwc2_hsotg *hsotg,
+				  unsigned int ep, unsigned int dir_in,
+				 unsigned int en)
+{
+	unsigned long flags;
+	u32 bit = 1 << ep;
+	u32 daint;
+
+	if (!dir_in)
+		bit <<= 16;
+
+	local_irq_save(flags);
+	daint = dwc2_readl(hsotg, DAINTMSK);
+	if (en)
+		daint |= bit;
+	else
+		daint &= ~bit;
+	dwc2_writel(hsotg, daint, DAINTMSK);
+	local_irq_restore(flags);
+}
+
+/**
+ * dwc2_hsotg_tx_fifo_count - return count of TX FIFOs in device mode
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ */
+int dwc2_hsotg_tx_fifo_count(struct dwc2_hsotg *hsotg)
+{
+	if (hsotg->hw_params.en_multiple_tx_fifo)
+		/* In dedicated FIFO mode we need count of IN EPs */
+		return hsotg->hw_params.num_dev_in_eps;
+	else
+		/* In shared FIFO mode we need count of Periodic IN EPs */
+		return hsotg->hw_params.num_dev_perio_in_ep;
+}
+
+/**
+ * dwc2_hsotg_tx_fifo_total_depth - return total FIFO depth available for
+ * device mode TX FIFOs
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ */
+int dwc2_hsotg_tx_fifo_total_depth(struct dwc2_hsotg *hsotg)
+{
+	int addr;
+	int tx_addr_max;
+	u32 np_tx_fifo_size;
+
+	np_tx_fifo_size = min_t(u32, hsotg->hw_params.dev_nperio_tx_fifo_size,
+				hsotg->params.g_np_tx_fifo_size);
+
+	/* Get Endpoint Info Control block size in DWORDs. */
+	tx_addr_max = hsotg->hw_params.total_fifo_size;
+
+	addr = hsotg->params.g_rx_fifo_size + np_tx_fifo_size;
+	if (tx_addr_max <= addr)
+		return 0;
+
+	return tx_addr_max - addr;
+}
+
+/**
+ * dwc2_gadget_wkup_alert_handler - Handler for WKUP_ALERT interrupt
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ */
+static void dwc2_gadget_wkup_alert_handler(struct dwc2_hsotg *hsotg)
+{
+	u32 gintsts2;
+	u32 gintmsk2;
+
+	gintsts2 = dwc2_readl(hsotg, GINTSTS2);
+	gintmsk2 = dwc2_readl(hsotg, GINTMSK2);
+	gintsts2 &= gintmsk2;
+
+	if (gintsts2 & GINTSTS2_WKUP_ALERT_INT) {
+		dev_dbg(hsotg->dev, "%s: Wkup_Alert_Int\n", __func__);
+		dwc2_set_bit(hsotg, GINTSTS2, GINTSTS2_WKUP_ALERT_INT);
+		dwc2_set_bit(hsotg, DCTL, DCTL_RMTWKUPSIG);
+	}
+}
+
+/**
+ * dwc2_hsotg_tx_fifo_average_depth - returns average depth of device mode
+ * TX FIFOs
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ */
+int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg)
+{
+	int tx_fifo_count;
+	int tx_fifo_depth;
+
+	tx_fifo_depth = dwc2_hsotg_tx_fifo_total_depth(hsotg);
+
+	tx_fifo_count = dwc2_hsotg_tx_fifo_count(hsotg);
+
+	if (!tx_fifo_count)
+		return tx_fifo_depth;
+	else
+		return tx_fifo_depth / tx_fifo_count;
+}
+
+/**
+ * dwc2_hsotg_init_fifo - initialise non-periodic FIFOs
+ * @hsotg: The device instance.
+ */
+static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
+{
+	unsigned int ep;
+	unsigned int addr;
+	int timeout;
+
+	u32 val;
+	u32 *txfsz = hsotg->params.g_tx_fifo_size;
+
+	/* Reset fifo map if not correctly cleared during previous session */
+	WARN_ON(hsotg->fifo_map);
+	hsotg->fifo_map = 0;
+
+	/* set RX/NPTX FIFO sizes */
+	dwc2_writel(hsotg, hsotg->params.g_rx_fifo_size, GRXFSIZ);
+	dwc2_writel(hsotg, (hsotg->params.g_rx_fifo_size <<
+		    FIFOSIZE_STARTADDR_SHIFT) |
+		    (hsotg->params.g_np_tx_fifo_size << FIFOSIZE_DEPTH_SHIFT),
+		    GNPTXFSIZ);
+
+	/*
+	 * arange all the rest of the TX FIFOs, as some versions of this
+	 * block have overlapping default addresses. This also ensures
+	 * that if the settings have been changed, then they are set to
+	 * known values.
+	 */
+
+	/* start at the end of the GNPTXFSIZ, rounded up */
+	addr = hsotg->params.g_rx_fifo_size + hsotg->params.g_np_tx_fifo_size;
+
+	/*
+	 * Configure fifos sizes from provided configuration and assign
+	 * them to endpoints dynamically according to maxpacket size value of
+	 * given endpoint.
+	 */
+	for (ep = 1; ep < MAX_EPS_CHANNELS; ep++) {
+		if (!txfsz[ep])
+			continue;
+		val = addr;
+		val |= txfsz[ep] << FIFOSIZE_DEPTH_SHIFT;
+		WARN_ONCE(addr + txfsz[ep] > hsotg->fifo_mem,
+			  "insufficient fifo memory");
+		addr += txfsz[ep];
+
+		dwc2_writel(hsotg, val, DPTXFSIZN(ep));
+		val = dwc2_readl(hsotg, DPTXFSIZN(ep));
+	}
+
+	dwc2_writel(hsotg, hsotg->hw_params.total_fifo_size |
+		    addr << GDFIFOCFG_EPINFOBASE_SHIFT,
+		    GDFIFOCFG);
+	/*
+	 * according to p428 of the design guide, we need to ensure that
+	 * all fifos are flushed before continuing
+	 */
+
+	dwc2_writel(hsotg, GRSTCTL_TXFNUM(0x10) | GRSTCTL_TXFFLSH |
+	       GRSTCTL_RXFFLSH, GRSTCTL);
+
+	/* wait until the fifos are both flushed */
+	timeout = 100;
+	while (1) {
+		val = dwc2_readl(hsotg, GRSTCTL);
+
+		if ((val & (GRSTCTL_TXFFLSH | GRSTCTL_RXFFLSH)) == 0)
+			break;
+
+		if (--timeout == 0) {
+			dev_err(hsotg->dev,
+				"%s: timeout flushing fifos (GRSTCTL=%08x)\n",
+				__func__, val);
+			break;
+		}
+
+		udelay(1);
+	}
+
+	dev_dbg(hsotg->dev, "FIFOs reset, timeout at %d\n", timeout);
+}
+
+/**
+ * dwc2_hsotg_ep_alloc_request - allocate USB rerequest structure
+ * @ep: USB endpoint to allocate request for.
+ * @flags: Allocation flags
+ *
+ * Allocate a new USB request structure appropriate for the specified endpoint
+ */
+static struct usb_request *dwc2_hsotg_ep_alloc_request(struct usb_ep *ep,
+						       gfp_t flags)
+{
+	struct dwc2_hsotg_req *req;
+
+	req = kzalloc(sizeof(*req), flags);
+	if (!req)
+		return NULL;
+
+	INIT_LIST_HEAD(&req->queue);
+
+	return &req->req;
+}
+
+/**
+ * is_ep_periodic - return true if the endpoint is in periodic mode.
+ * @hs_ep: The endpoint to query.
+ *
+ * Returns true if the endpoint is in periodic mode, meaning it is being
+ * used for an Interrupt or ISO transfer.
+ */
+static inline int is_ep_periodic(struct dwc2_hsotg_ep *hs_ep)
+{
+	return hs_ep->periodic;
+}
+
+/**
+ * dwc2_hsotg_unmap_dma - unmap the DMA memory being used for the request
+ * @hsotg: The device state.
+ * @hs_ep: The endpoint for the request
+ * @hs_req: The request being processed.
+ *
+ * This is the reverse of dwc2_hsotg_map_dma(), called for the completion
+ * of a request to ensure the buffer is ready for access by the caller.
+ */
+static void dwc2_hsotg_unmap_dma(struct dwc2_hsotg *hsotg,
+				 struct dwc2_hsotg_ep *hs_ep,
+				struct dwc2_hsotg_req *hs_req)
+{
+	struct usb_request *req = &hs_req->req;
+
+	usb_gadget_unmap_request(&hsotg->gadget, req, hs_ep->map_dir);
+}
+
+/*
+ * dwc2_gadget_alloc_ctrl_desc_chains - allocate DMA descriptor chains
+ * for Control endpoint
+ * @hsotg: The device state.
+ *
+ * This function will allocate 4 descriptor chains for EP 0: 2 for
+ * Setup stage, per one for IN and OUT data/status transactions.
+ */
+static int dwc2_gadget_alloc_ctrl_desc_chains(struct dwc2_hsotg *hsotg)
+{
+	hsotg->setup_desc[0] =
+		dmam_alloc_coherent(hsotg->dev,
+				    sizeof(struct dwc2_dma_desc),
+				    &hsotg->setup_desc_dma[0],
+				    GFP_KERNEL);
+	if (!hsotg->setup_desc[0])
+		goto fail;
+
+	hsotg->setup_desc[1] =
+		dmam_alloc_coherent(hsotg->dev,
+				    sizeof(struct dwc2_dma_desc),
+				    &hsotg->setup_desc_dma[1],
+				    GFP_KERNEL);
+	if (!hsotg->setup_desc[1])
+		goto fail;
+
+	hsotg->ctrl_in_desc =
+		dmam_alloc_coherent(hsotg->dev,
+				    sizeof(struct dwc2_dma_desc),
+				    &hsotg->ctrl_in_desc_dma,
+				    GFP_KERNEL);
+	if (!hsotg->ctrl_in_desc)
+		goto fail;
+
+	hsotg->ctrl_out_desc =
+		dmam_alloc_coherent(hsotg->dev,
+				    sizeof(struct dwc2_dma_desc),
+				    &hsotg->ctrl_out_desc_dma,
+				    GFP_KERNEL);
+	if (!hsotg->ctrl_out_desc)
+		goto fail;
+
+	return 0;
+
+fail:
+	return -ENOMEM;
+}
+
+/**
+ * dwc2_hsotg_write_fifo - write packet Data to the TxFIFO
+ * @hsotg: The controller state.
+ * @hs_ep: The endpoint we're going to write for.
+ * @hs_req: The request to write data for.
+ *
+ * This is called when the TxFIFO has some space in it to hold a new
+ * transmission and we have something to give it. The actual setup of
+ * the data size is done elsewhere, so all we have to do is to actually
+ * write the data.
+ *
+ * The return value is zero if there is more space (or nothing was done)
+ * otherwise -ENOSPC is returned if the FIFO space was used up.
+ *
+ * This routine is only needed for PIO
+ */
+static int dwc2_hsotg_write_fifo(struct dwc2_hsotg *hsotg,
+				 struct dwc2_hsotg_ep *hs_ep,
+				struct dwc2_hsotg_req *hs_req)
+{
+	bool periodic = is_ep_periodic(hs_ep);
+	u32 gnptxsts = dwc2_readl(hsotg, GNPTXSTS);
+	int buf_pos = hs_req->req.actual;
+	int to_write = hs_ep->size_loaded;
+	void *data;
+	int can_write;
+	int pkt_round;
+	int max_transfer;
+
+	to_write -= (buf_pos - hs_ep->last_load);
+
+	/* if there's nothing to write, get out early */
+	if (to_write == 0)
+		return 0;
+
+	if (periodic && !hsotg->dedicated_fifos) {
+		u32 epsize = dwc2_readl(hsotg, DIEPTSIZ(hs_ep->index));
+		int size_left;
+		int size_done;
+
+		/*
+		 * work out how much data was loaded so we can calculate
+		 * how much data is left in the fifo.
+		 */
+
+		size_left = DXEPTSIZ_XFERSIZE_GET(epsize);
+
+		/*
+		 * if shared fifo, we cannot write anything until the
+		 * previous data has been completely sent.
+		 */
+		if (hs_ep->fifo_load != 0) {
+			dwc2_hsotg_en_gsint(hsotg, GINTSTS_PTXFEMP);
+			return -ENOSPC;
+		}
+
+		dev_dbg(hsotg->dev, "%s: left=%d, load=%d, fifo=%d, size %d\n",
+			__func__, size_left,
+			hs_ep->size_loaded, hs_ep->fifo_load, hs_ep->fifo_size);
+
+		/* how much of the data has moved */
+		size_done = hs_ep->size_loaded - size_left;
+
+		/* how much data is left in the fifo */
+		can_write = hs_ep->fifo_load - size_done;
+		dev_dbg(hsotg->dev, "%s: => can_write1=%d\n",
+			__func__, can_write);
+
+		can_write = hs_ep->fifo_size - can_write;
+		dev_dbg(hsotg->dev, "%s: => can_write2=%d\n",
+			__func__, can_write);
+
+		if (can_write <= 0) {
+			dwc2_hsotg_en_gsint(hsotg, GINTSTS_PTXFEMP);
+			return -ENOSPC;
+		}
+	} else if (hsotg->dedicated_fifos && hs_ep->index != 0) {
+		can_write = dwc2_readl(hsotg,
+				       DTXFSTS(hs_ep->fifo_index));
+
+		can_write &= 0xffff;
+		can_write *= 4;
+	} else {
+		if (GNPTXSTS_NP_TXQ_SPC_AVAIL_GET(gnptxsts) == 0) {
+			dev_dbg(hsotg->dev,
+				"%s: no queue slots available (0x%08x)\n",
+				__func__, gnptxsts);
+
+			dwc2_hsotg_en_gsint(hsotg, GINTSTS_NPTXFEMP);
+			return -ENOSPC;
+		}
+
+		can_write = GNPTXSTS_NP_TXF_SPC_AVAIL_GET(gnptxsts);
+		can_write *= 4;	/* fifo size is in 32bit quantities. */
+	}
+
+	max_transfer = hs_ep->ep.maxpacket * hs_ep->mc;
+
+	dev_dbg(hsotg->dev, "%s: GNPTXSTS=%08x, can=%d, to=%d, max_transfer %d\n",
+		__func__, gnptxsts, can_write, to_write, max_transfer);
+
+	/*
+	 * limit to 512 bytes of data, it seems at least on the non-periodic
+	 * FIFO, requests of >512 cause the endpoint to get stuck with a
+	 * fragment of the end of the transfer in it.
+	 */
+	if (can_write > 512 && !periodic)
+		can_write = 512;
+
+	/*
+	 * limit the write to one max-packet size worth of data, but allow
+	 * the transfer to return that it did not run out of fifo space
+	 * doing it.
+	 */
+	if (to_write > max_transfer) {
+		to_write = max_transfer;
+
+		/* it's needed only when we do not use dedicated fifos */
+		if (!hsotg->dedicated_fifos)
+			dwc2_hsotg_en_gsint(hsotg,
+					    periodic ? GINTSTS_PTXFEMP :
+					   GINTSTS_NPTXFEMP);
+	}
+
+	/* see if we can write data */
+
+	if (to_write > can_write) {
+		to_write = can_write;
+		pkt_round = to_write % max_transfer;
+
+		/*
+		 * Round the write down to an
+		 * exact number of packets.
+		 *
+		 * Note, we do not currently check to see if we can ever
+		 * write a full packet or not to the FIFO.
+		 */
+
+		if (pkt_round)
+			to_write -= pkt_round;
+
+		/*
+		 * enable correct FIFO interrupt to alert us when there
+		 * is more room left.
+		 */
+
+		/* it's needed only when we do not use dedicated fifos */
+		if (!hsotg->dedicated_fifos)
+			dwc2_hsotg_en_gsint(hsotg,
+					    periodic ? GINTSTS_PTXFEMP :
+					   GINTSTS_NPTXFEMP);
+	}
+
+	dev_dbg(hsotg->dev, "write %d/%d, can_write %d, done %d\n",
+		to_write, hs_req->req.length, can_write, buf_pos);
+
+	if (to_write <= 0)
+		return -ENOSPC;
+
+	hs_req->req.actual = buf_pos + to_write;
+	hs_ep->total_data += to_write;
+
+	if (periodic)
+		hs_ep->fifo_load += to_write;
+
+	to_write = DIV_ROUND_UP(to_write, 4);
+	data = hs_req->req.buf + buf_pos;
+
+	dwc2_writel_rep(hsotg, EPFIFO(hs_ep->index), data, to_write);
+
+	return (to_write >= can_write) ? -ENOSPC : 0;
+}
+
+/**
+ * get_ep_limit - get the maximum data legnth for this endpoint
+ * @hs_ep: The endpoint
+ *
+ * Return the maximum data that can be queued in one go on a given endpoint
+ * so that transfers that are too long can be split.
+ */
+static unsigned int get_ep_limit(struct dwc2_hsotg_ep *hs_ep)
+{
+	int index = hs_ep->index;
+	unsigned int maxsize;
+	unsigned int maxpkt;
+
+	if (index != 0) {
+		maxsize = DXEPTSIZ_XFERSIZE_LIMIT + 1;
+		maxpkt = DXEPTSIZ_PKTCNT_LIMIT + 1;
+	} else {
+		maxsize = 64 + 64;
+		if (hs_ep->dir_in)
+			maxpkt = DIEPTSIZ0_PKTCNT_LIMIT + 1;
+		else
+			maxpkt = 2;
+	}
+
+	/* we made the constant loading easier above by using +1 */
+	maxpkt--;
+	maxsize--;
+
+	/*
+	 * constrain by packet count if maxpkts*pktsize is greater
+	 * than the length register size.
+	 */
+
+	if ((maxpkt * hs_ep->ep.maxpacket) < maxsize)
+		maxsize = maxpkt * hs_ep->ep.maxpacket;
+
+	return maxsize;
+}
+
+/**
+ * dwc2_hsotg_read_frameno - read current frame number
+ * @hsotg: The device instance
+ *
+ * Return the current frame number
+ */
+static u32 dwc2_hsotg_read_frameno(struct dwc2_hsotg *hsotg)
+{
+	u32 dsts;
+
+	dsts = dwc2_readl(hsotg, DSTS);
+	dsts &= DSTS_SOFFN_MASK;
+	dsts >>= DSTS_SOFFN_SHIFT;
+
+	return dsts;
+}
+
+/**
+ * dwc2_gadget_get_chain_limit - get the maximum data payload value of the
+ * DMA descriptor chain prepared for specific endpoint
+ * @hs_ep: The endpoint
+ *
+ * Return the maximum data that can be queued in one go on a given endpoint
+ * depending on its descriptor chain capacity so that transfers that
+ * are too long can be split.
+ */
+static unsigned int dwc2_gadget_get_chain_limit(struct dwc2_hsotg_ep *hs_ep)
+{
+	const struct usb_endpoint_descriptor *ep_desc = hs_ep->ep.desc;
+	int is_isoc = hs_ep->isochronous;
+	unsigned int maxsize;
+	u32 mps = hs_ep->ep.maxpacket;
+	int dir_in = hs_ep->dir_in;
+
+	if (is_isoc)
+		maxsize = (hs_ep->dir_in ? DEV_DMA_ISOC_TX_NBYTES_LIMIT :
+					   DEV_DMA_ISOC_RX_NBYTES_LIMIT) *
+					   MAX_DMA_DESC_NUM_HS_ISOC;
+	else
+		maxsize = DEV_DMA_NBYTES_LIMIT * MAX_DMA_DESC_NUM_GENERIC;
+
+	/* Interrupt OUT EP with mps not multiple of 4 */
+	if (hs_ep->index)
+		if (usb_endpoint_xfer_int(ep_desc) && !dir_in && (mps % 4))
+			maxsize = mps * MAX_DMA_DESC_NUM_GENERIC;
+
+	return maxsize;
+}
+
+/*
+ * dwc2_gadget_get_desc_params - get DMA descriptor parameters.
+ * @hs_ep: The endpoint
+ * @mask: RX/TX bytes mask to be defined
+ *
+ * Returns maximum data payload for one descriptor after analyzing endpoint
+ * characteristics.
+ * DMA descriptor transfer bytes limit depends on EP type:
+ * Control out - MPS,
+ * Isochronous - descriptor rx/tx bytes bitfield limit,
+ * Control In/Bulk/Interrupt - multiple of mps. This will allow to not
+ * have concatenations from various descriptors within one packet.
+ * Interrupt OUT - if mps not multiple of 4 then a single packet corresponds
+ * to a single descriptor.
+ *
+ * Selects corresponding mask for RX/TX bytes as well.
+ */
+static u32 dwc2_gadget_get_desc_params(struct dwc2_hsotg_ep *hs_ep, u32 *mask)
+{
+	const struct usb_endpoint_descriptor *ep_desc = hs_ep->ep.desc;
+	u32 mps = hs_ep->ep.maxpacket;
+	int dir_in = hs_ep->dir_in;
+	u32 desc_size = 0;
+
+	if (!hs_ep->index && !dir_in) {
+		desc_size = mps;
+		*mask = DEV_DMA_NBYTES_MASK;
+	} else if (hs_ep->isochronous) {
+		if (dir_in) {
+			desc_size = DEV_DMA_ISOC_TX_NBYTES_LIMIT;
+			*mask = DEV_DMA_ISOC_TX_NBYTES_MASK;
+		} else {
+			desc_size = DEV_DMA_ISOC_RX_NBYTES_LIMIT;
+			*mask = DEV_DMA_ISOC_RX_NBYTES_MASK;
+		}
+	} else {
+		desc_size = DEV_DMA_NBYTES_LIMIT;
+		*mask = DEV_DMA_NBYTES_MASK;
+
+		/* Round down desc_size to be mps multiple */
+		desc_size -= desc_size % mps;
+	}
+
+	/* Interrupt OUT EP with mps not multiple of 4 */
+	if (hs_ep->index)
+		if (usb_endpoint_xfer_int(ep_desc) && !dir_in && (mps % 4)) {
+			desc_size = mps;
+			*mask = DEV_DMA_NBYTES_MASK;
+		}
+
+	return desc_size;
+}
+
+static void dwc2_gadget_fill_nonisoc_xfer_ddma_one(struct dwc2_hsotg_ep *hs_ep,
+						 struct dwc2_dma_desc **desc,
+						 dma_addr_t dma_buff,
+						 unsigned int len,
+						 bool true_last)
+{
+	int dir_in = hs_ep->dir_in;
+	u32 mps = hs_ep->ep.maxpacket;
+	u32 maxsize = 0;
+	u32 offset = 0;
+	u32 mask = 0;
+	int i;
+
+	maxsize = dwc2_gadget_get_desc_params(hs_ep, &mask);
+
+	hs_ep->desc_count = (len / maxsize) +
+				((len % maxsize) ? 1 : 0);
+	if (len == 0)
+		hs_ep->desc_count = 1;
+
+	for (i = 0; i < hs_ep->desc_count; ++i) {
+		(*desc)->status = 0;
+		(*desc)->status |= (DEV_DMA_BUFF_STS_HBUSY
+				 << DEV_DMA_BUFF_STS_SHIFT);
+
+		if (len > maxsize) {
+			if (!hs_ep->index && !dir_in)
+				(*desc)->status |= (DEV_DMA_L | DEV_DMA_IOC);
+
+			(*desc)->status |=
+				maxsize << DEV_DMA_NBYTES_SHIFT & mask;
+			(*desc)->buf = dma_buff + offset;
+
+			len -= maxsize;
+			offset += maxsize;
+		} else {
+			if (true_last)
+				(*desc)->status |= (DEV_DMA_L | DEV_DMA_IOC);
+
+			if (dir_in)
+				(*desc)->status |= (len % mps) ? DEV_DMA_SHORT :
+					((hs_ep->send_zlp && true_last) ?
+					DEV_DMA_SHORT : 0);
+
+			(*desc)->status |=
+				len << DEV_DMA_NBYTES_SHIFT & mask;
+			(*desc)->buf = dma_buff + offset;
+		}
+
+		(*desc)->status &= ~DEV_DMA_BUFF_STS_MASK;
+		(*desc)->status |= (DEV_DMA_BUFF_STS_HREADY
+				 << DEV_DMA_BUFF_STS_SHIFT);
+		(*desc)++;
+	}
+}
+
+/*
+ * dwc2_gadget_config_nonisoc_xfer_ddma - prepare non ISOC DMA desc chain.
+ * @hs_ep: The endpoint
+ * @ureq: Request to transfer
+ * @offset: offset in bytes
+ * @len: Length of the transfer
+ *
+ * This function will iterate over descriptor chain and fill its entries
+ * with corresponding information based on transfer data.
+ */
+static void dwc2_gadget_config_nonisoc_xfer_ddma(struct dwc2_hsotg_ep *hs_ep,
+						 dma_addr_t dma_buff,
+						 unsigned int len)
+{
+	struct usb_request *ureq = NULL;
+	struct dwc2_dma_desc *desc = hs_ep->desc_list;
+	struct scatterlist *sg;
+	int i;
+	u8 desc_count = 0;
+
+	if (hs_ep->req)
+		ureq = &hs_ep->req->req;
+
+	/* non-DMA sg buffer */
+	if (!ureq || !ureq->num_sgs) {
+		dwc2_gadget_fill_nonisoc_xfer_ddma_one(hs_ep, &desc,
+			dma_buff, len, true);
+		return;
+	}
+
+	/* DMA sg buffer */
+	for_each_sg(ureq->sg, sg, ureq->num_sgs, i) {
+		dwc2_gadget_fill_nonisoc_xfer_ddma_one(hs_ep, &desc,
+			sg_dma_address(sg) + sg->offset, sg_dma_len(sg),
+			sg_is_last(sg));
+		desc_count += hs_ep->desc_count;
+	}
+
+	hs_ep->desc_count = desc_count;
+}
+
+/*
+ * dwc2_gadget_fill_isoc_desc - fills next isochronous descriptor in chain.
+ * @hs_ep: The isochronous endpoint.
+ * @dma_buff: usb requests dma buffer.
+ * @len: usb request transfer length.
+ *
+ * Fills next free descriptor with the data of the arrived usb request,
+ * frame info, sets Last and IOC bits increments next_desc. If filled
+ * descriptor is not the first one, removes L bit from the previous descriptor
+ * status.
+ */
+static int dwc2_gadget_fill_isoc_desc(struct dwc2_hsotg_ep *hs_ep,
+				      dma_addr_t dma_buff, unsigned int len)
+{
+	struct dwc2_dma_desc *desc;
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	u32 index;
+	u32 mask = 0;
+	u8 pid = 0;
+
+	dwc2_gadget_get_desc_params(hs_ep, &mask);
+
+	index = hs_ep->next_desc;
+	desc = &hs_ep->desc_list[index];
+
+	/* Check if descriptor chain full */
+	if ((desc->status >> DEV_DMA_BUFF_STS_SHIFT) ==
+	    DEV_DMA_BUFF_STS_HREADY) {
+		dev_dbg(hsotg->dev, "%s: desc chain full\n", __func__);
+		return 1;
+	}
+
+	/* Clear L bit of previous desc if more than one entries in the chain */
+	if (hs_ep->next_desc)
+		hs_ep->desc_list[index - 1].status &= ~DEV_DMA_L;
+
+	dev_dbg(hsotg->dev, "%s: Filling ep %d, dir %s isoc desc # %d\n",
+		__func__, hs_ep->index, hs_ep->dir_in ? "in" : "out", index);
+
+	desc->status = 0;
+	desc->status |= (DEV_DMA_BUFF_STS_HBUSY	<< DEV_DMA_BUFF_STS_SHIFT);
+
+	desc->buf = dma_buff;
+	desc->status |= (DEV_DMA_L | DEV_DMA_IOC |
+			 ((len << DEV_DMA_NBYTES_SHIFT) & mask));
+
+	if (hs_ep->dir_in) {
+		if (len)
+			pid = DIV_ROUND_UP(len, hs_ep->ep.maxpacket);
+		else
+			pid = 1;
+		desc->status |= ((pid << DEV_DMA_ISOC_PID_SHIFT) &
+				 DEV_DMA_ISOC_PID_MASK) |
+				((len % hs_ep->ep.maxpacket) ?
+				 DEV_DMA_SHORT : 0) |
+				((hs_ep->target_frame <<
+				  DEV_DMA_ISOC_FRNUM_SHIFT) &
+				 DEV_DMA_ISOC_FRNUM_MASK);
+	}
+
+	desc->status &= ~DEV_DMA_BUFF_STS_MASK;
+	desc->status |= (DEV_DMA_BUFF_STS_HREADY << DEV_DMA_BUFF_STS_SHIFT);
+
+	/* Increment frame number by interval for IN */
+	if (hs_ep->dir_in)
+		dwc2_gadget_incr_frame_num(hs_ep);
+
+	/* Update index of last configured entry in the chain */
+	hs_ep->next_desc++;
+	if (hs_ep->next_desc >= MAX_DMA_DESC_NUM_HS_ISOC)
+		hs_ep->next_desc = 0;
+
+	return 0;
+}
+
+/*
+ * dwc2_gadget_start_isoc_ddma - start isochronous transfer in DDMA
+ * @hs_ep: The isochronous endpoint.
+ *
+ * Prepare descriptor chain for isochronous endpoints. Afterwards
+ * write DMA address to HW and enable the endpoint.
+ */
+static void dwc2_gadget_start_isoc_ddma(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	struct dwc2_hsotg_req *hs_req, *treq;
+	int index = hs_ep->index;
+	int ret;
+	int i;
+	u32 dma_reg;
+	u32 depctl;
+	u32 ctrl;
+	struct dwc2_dma_desc *desc;
+
+	if (list_empty(&hs_ep->queue)) {
+		hs_ep->target_frame = TARGET_FRAME_INITIAL;
+		dev_dbg(hsotg->dev, "%s: No requests in queue\n", __func__);
+		return;
+	}
+
+	/* Initialize descriptor chain by Host Busy status */
+	for (i = 0; i < MAX_DMA_DESC_NUM_HS_ISOC; i++) {
+		desc = &hs_ep->desc_list[i];
+		desc->status = 0;
+		desc->status |= (DEV_DMA_BUFF_STS_HBUSY
+				    << DEV_DMA_BUFF_STS_SHIFT);
+	}
+
+	hs_ep->next_desc = 0;
+	list_for_each_entry_safe(hs_req, treq, &hs_ep->queue, queue) {
+		dma_addr_t dma_addr = hs_req->req.dma;
+
+		if (hs_req->req.num_sgs) {
+			WARN_ON(hs_req->req.num_sgs > 1);
+			dma_addr = sg_dma_address(hs_req->req.sg);
+		}
+		ret = dwc2_gadget_fill_isoc_desc(hs_ep, dma_addr,
+						 hs_req->req.length);
+		if (ret)
+			break;
+	}
+
+	hs_ep->compl_desc = 0;
+	depctl = hs_ep->dir_in ? DIEPCTL(index) : DOEPCTL(index);
+	dma_reg = hs_ep->dir_in ? DIEPDMA(index) : DOEPDMA(index);
+
+	/* write descriptor chain address to control register */
+	dwc2_writel(hsotg, hs_ep->desc_list_dma, dma_reg);
+
+	ctrl = dwc2_readl(hsotg, depctl);
+	ctrl |= DXEPCTL_EPENA | DXEPCTL_CNAK;
+	dwc2_writel(hsotg, ctrl, depctl);
+}
+
+static bool dwc2_gadget_target_frame_elapsed(struct dwc2_hsotg_ep *hs_ep);
+static void dwc2_hsotg_complete_request(struct dwc2_hsotg *hsotg,
+					struct dwc2_hsotg_ep *hs_ep,
+				       struct dwc2_hsotg_req *hs_req,
+				       int result);
+
+/**
+ * dwc2_hsotg_start_req - start a USB request from an endpoint's queue
+ * @hsotg: The controller state.
+ * @hs_ep: The endpoint to process a request for
+ * @hs_req: The request to start.
+ * @continuing: True if we are doing more for the current request.
+ *
+ * Start the given request running by setting the endpoint registers
+ * appropriately, and writing any data to the FIFOs.
+ */
+static void dwc2_hsotg_start_req(struct dwc2_hsotg *hsotg,
+				 struct dwc2_hsotg_ep *hs_ep,
+				struct dwc2_hsotg_req *hs_req,
+				bool continuing)
+{
+	struct usb_request *ureq = &hs_req->req;
+	int index = hs_ep->index;
+	int dir_in = hs_ep->dir_in;
+	u32 epctrl_reg;
+	u32 epsize_reg;
+	u32 epsize;
+	u32 ctrl;
+	unsigned int length;
+	unsigned int packets;
+	unsigned int maxreq;
+	unsigned int dma_reg;
+
+	if (index != 0) {
+		if (hs_ep->req && !continuing) {
+			dev_err(hsotg->dev, "%s: active request\n", __func__);
+			WARN_ON(1);
+			return;
+		} else if (hs_ep->req != hs_req && continuing) {
+			dev_err(hsotg->dev,
+				"%s: continue different req\n", __func__);
+			WARN_ON(1);
+			return;
+		}
+	}
+
+	dma_reg = dir_in ? DIEPDMA(index) : DOEPDMA(index);
+	epctrl_reg = dir_in ? DIEPCTL(index) : DOEPCTL(index);
+	epsize_reg = dir_in ? DIEPTSIZ(index) : DOEPTSIZ(index);
+
+	dev_dbg(hsotg->dev, "%s: DxEPCTL=0x%08x, ep %d, dir %s\n",
+		__func__, dwc2_readl(hsotg, epctrl_reg), index,
+		hs_ep->dir_in ? "in" : "out");
+
+	/* If endpoint is stalled, we will restart request later */
+	ctrl = dwc2_readl(hsotg, epctrl_reg);
+
+	if (index && ctrl & DXEPCTL_STALL) {
+		dev_warn(hsotg->dev, "%s: ep%d is stalled\n", __func__, index);
+		return;
+	}
+
+	length = ureq->length - ureq->actual;
+	dev_dbg(hsotg->dev, "ureq->length:%d ureq->actual:%d\n",
+		ureq->length, ureq->actual);
+
+	if (!using_desc_dma(hsotg))
+		maxreq = get_ep_limit(hs_ep);
+	else
+		maxreq = dwc2_gadget_get_chain_limit(hs_ep);
+
+	if (length > maxreq) {
+		int round = maxreq % hs_ep->ep.maxpacket;
+
+		dev_dbg(hsotg->dev, "%s: length %d, max-req %d, r %d\n",
+			__func__, length, maxreq, round);
+
+		/* round down to multiple of packets */
+		if (round)
+			maxreq -= round;
+
+		length = maxreq;
+	}
+
+	if (length)
+		packets = DIV_ROUND_UP(length, hs_ep->ep.maxpacket);
+	else
+		packets = 1;	/* send one packet if length is zero. */
+
+	if (dir_in && index != 0)
+		if (hs_ep->isochronous)
+			epsize = DXEPTSIZ_MC(packets);
+		else
+			epsize = DXEPTSIZ_MC(1);
+	else
+		epsize = 0;
+
+	/*
+	 * zero length packet should be programmed on its own and should not
+	 * be counted in DIEPTSIZ.PktCnt with other packets.
+	 */
+	if (dir_in && ureq->zero && !continuing) {
+		/* Test if zlp is actually required. */
+		if ((ureq->length >= hs_ep->ep.maxpacket) &&
+		    !(ureq->length % hs_ep->ep.maxpacket))
+			hs_ep->send_zlp = 1;
+	}
+
+	epsize |= DXEPTSIZ_PKTCNT(packets);
+	epsize |= DXEPTSIZ_XFERSIZE(length);
+
+	dev_dbg(hsotg->dev, "%s: %d@%d/%d, 0x%08x => 0x%08x\n",
+		__func__, packets, length, ureq->length, epsize, epsize_reg);
+
+	/* store the request as the current one we're doing */
+	hs_ep->req = hs_req;
+
+	if (using_desc_dma(hsotg)) {
+		u32 offset = 0;
+		u32 mps = hs_ep->ep.maxpacket;
+
+		/* Adjust length: EP0 - MPS, other OUT EPs - multiple of MPS */
+		if (!dir_in) {
+			if (!index)
+				length = mps;
+			else if (length % mps)
+				length += (mps - (length % mps));
+		}
+
+		if (continuing)
+			offset = ureq->actual;
+
+		/* Fill DDMA chain entries */
+		dwc2_gadget_config_nonisoc_xfer_ddma(hs_ep, ureq->dma + offset,
+						     length);
+
+		/* write descriptor chain address to control register */
+		dwc2_writel(hsotg, hs_ep->desc_list_dma, dma_reg);
+
+		dev_dbg(hsotg->dev, "%s: %08x pad => 0x%08x\n",
+			__func__, (u32)hs_ep->desc_list_dma, dma_reg);
+	} else {
+		/* write size / packets */
+		dwc2_writel(hsotg, epsize, epsize_reg);
+
+		if (using_dma(hsotg) && !continuing && (length != 0)) {
+			/*
+			 * write DMA address to control register, buffer
+			 * already synced by dwc2_hsotg_ep_queue().
+			 */
+
+			dwc2_writel(hsotg, ureq->dma, dma_reg);
+
+			dev_dbg(hsotg->dev, "%s: %pad => 0x%08x\n",
+				__func__, &ureq->dma, dma_reg);
+		}
+	}
+
+	if (hs_ep->isochronous) {
+		if (!dwc2_gadget_target_frame_elapsed(hs_ep)) {
+			if (hs_ep->interval == 1) {
+				if (hs_ep->target_frame & 0x1)
+					ctrl |= DXEPCTL_SETODDFR;
+				else
+					ctrl |= DXEPCTL_SETEVENFR;
+			}
+			ctrl |= DXEPCTL_CNAK;
+		} else {
+			hs_req->req.frame_number = hs_ep->target_frame;
+			hs_req->req.actual = 0;
+			dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, -ENODATA);
+			return;
+		}
+	}
+
+	ctrl |= DXEPCTL_EPENA;	/* ensure ep enabled */
+
+	dev_dbg(hsotg->dev, "ep0 state:%d\n", hsotg->ep0_state);
+
+	/* For Setup request do not clear NAK */
+	if (!(index == 0 && hsotg->ep0_state == DWC2_EP0_SETUP))
+		ctrl |= DXEPCTL_CNAK;	/* clear NAK set by core */
+
+	dev_dbg(hsotg->dev, "%s: DxEPCTL=0x%08x\n", __func__, ctrl);
+	dwc2_writel(hsotg, ctrl, epctrl_reg);
+
+	/*
+	 * set these, it seems that DMA support increments past the end
+	 * of the packet buffer so we need to calculate the length from
+	 * this information.
+	 */
+	hs_ep->size_loaded = length;
+	hs_ep->last_load = ureq->actual;
+
+	if (dir_in && !using_dma(hsotg)) {
+		/* set these anyway, we may need them for non-periodic in */
+		hs_ep->fifo_load = 0;
+
+		dwc2_hsotg_write_fifo(hsotg, hs_ep, hs_req);
+	}
+
+	/*
+	 * Note, trying to clear the NAK here causes problems with transmit
+	 * on the S3C6400 ending up with the TXFIFO becoming full.
+	 */
+
+	/* check ep is enabled */
+	if (!(dwc2_readl(hsotg, epctrl_reg) & DXEPCTL_EPENA))
+		dev_dbg(hsotg->dev,
+			"ep%d: failed to become enabled (DXEPCTL=0x%08x)?\n",
+			 index, dwc2_readl(hsotg, epctrl_reg));
+
+	dev_dbg(hsotg->dev, "%s: DXEPCTL=0x%08x\n",
+		__func__, dwc2_readl(hsotg, epctrl_reg));
+
+	/* enable ep interrupts */
+	dwc2_hsotg_ctrl_epint(hsotg, hs_ep->index, hs_ep->dir_in, 1);
+}
+
+/**
+ * dwc2_hsotg_map_dma - map the DMA memory being used for the request
+ * @hsotg: The device state.
+ * @hs_ep: The endpoint the request is on.
+ * @req: The request being processed.
+ *
+ * We've been asked to queue a request, so ensure that the memory buffer
+ * is correctly setup for DMA. If we've been passed an extant DMA address
+ * then ensure the buffer has been synced to memory. If our buffer has no
+ * DMA memory, then we map the memory and mark our request to allow us to
+ * cleanup on completion.
+ */
+static int dwc2_hsotg_map_dma(struct dwc2_hsotg *hsotg,
+			      struct dwc2_hsotg_ep *hs_ep,
+			     struct usb_request *req)
+{
+	int ret;
+
+	hs_ep->map_dir = hs_ep->dir_in;
+	ret = usb_gadget_map_request(&hsotg->gadget, req, hs_ep->dir_in);
+	if (ret)
+		goto dma_error;
+
+	return 0;
+
+dma_error:
+	dev_err(hsotg->dev, "%s: failed to map buffer %p, %d bytes\n",
+		__func__, req->buf, req->length);
+
+	return -EIO;
+}
+
+static int dwc2_hsotg_handle_unaligned_buf_start(struct dwc2_hsotg *hsotg,
+						 struct dwc2_hsotg_ep *hs_ep,
+						 struct dwc2_hsotg_req *hs_req)
+{
+	void *req_buf = hs_req->req.buf;
+
+	/* If dma is not being used or buffer is aligned */
+	if (!using_dma(hsotg) || !((long)req_buf & 3))
+		return 0;
+
+	WARN_ON(hs_req->saved_req_buf);
+
+	dev_dbg(hsotg->dev, "%s: %s: buf=%p length=%d\n", __func__,
+		hs_ep->ep.name, req_buf, hs_req->req.length);
+
+	hs_req->req.buf = kmalloc(hs_req->req.length, GFP_ATOMIC);
+	if (!hs_req->req.buf) {
+		hs_req->req.buf = req_buf;
+		dev_err(hsotg->dev,
+			"%s: unable to allocate memory for bounce buffer\n",
+			__func__);
+		return -ENOMEM;
+	}
+
+	/* Save actual buffer */
+	hs_req->saved_req_buf = req_buf;
+
+	if (hs_ep->dir_in)
+		memcpy(hs_req->req.buf, req_buf, hs_req->req.length);
+	return 0;
+}
+
+static void
+dwc2_hsotg_handle_unaligned_buf_complete(struct dwc2_hsotg *hsotg,
+					 struct dwc2_hsotg_ep *hs_ep,
+					 struct dwc2_hsotg_req *hs_req)
+{
+	/* If dma is not being used or buffer was aligned */
+	if (!using_dma(hsotg) || !hs_req->saved_req_buf)
+		return;
+
+	dev_dbg(hsotg->dev, "%s: %s: status=%d actual-length=%d\n", __func__,
+		hs_ep->ep.name, hs_req->req.status, hs_req->req.actual);
+
+	/* Copy data from bounce buffer on successful out transfer */
+	if (!hs_ep->dir_in && !hs_req->req.status)
+		memcpy(hs_req->saved_req_buf, hs_req->req.buf,
+		       hs_req->req.actual);
+
+	/* Free bounce buffer */
+	kfree(hs_req->req.buf);
+
+	hs_req->req.buf = hs_req->saved_req_buf;
+	hs_req->saved_req_buf = NULL;
+}
+
+/**
+ * dwc2_gadget_target_frame_elapsed - Checks target frame
+ * @hs_ep: The driver endpoint to check
+ *
+ * Returns 1 if targeted frame elapsed. If returned 1 then we need to drop
+ * corresponding transfer.
+ */
+static bool dwc2_gadget_target_frame_elapsed(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	u32 target_frame = hs_ep->target_frame;
+	u32 current_frame = hsotg->frame_number;
+	bool frame_overrun = hs_ep->frame_overrun;
+	u16 limit = DSTS_SOFFN_LIMIT;
+
+	if (hsotg->gadget.speed != USB_SPEED_HIGH)
+		limit >>= 3;
+
+	if (!frame_overrun && current_frame >= target_frame)
+		return true;
+
+	if (frame_overrun && current_frame >= target_frame &&
+	    ((current_frame - target_frame) < limit / 2))
+		return true;
+
+	return false;
+}
+
+/*
+ * dwc2_gadget_set_ep0_desc_chain - Set EP's desc chain pointers
+ * @hsotg: The driver state
+ * @hs_ep: the ep descriptor chain is for
+ *
+ * Called to update EP0 structure's pointers depend on stage of
+ * control transfer.
+ */
+static int dwc2_gadget_set_ep0_desc_chain(struct dwc2_hsotg *hsotg,
+					  struct dwc2_hsotg_ep *hs_ep)
+{
+	switch (hsotg->ep0_state) {
+	case DWC2_EP0_SETUP:
+	case DWC2_EP0_STATUS_OUT:
+		hs_ep->desc_list = hsotg->setup_desc[0];
+		hs_ep->desc_list_dma = hsotg->setup_desc_dma[0];
+		break;
+	case DWC2_EP0_DATA_IN:
+	case DWC2_EP0_STATUS_IN:
+		hs_ep->desc_list = hsotg->ctrl_in_desc;
+		hs_ep->desc_list_dma = hsotg->ctrl_in_desc_dma;
+		break;
+	case DWC2_EP0_DATA_OUT:
+		hs_ep->desc_list = hsotg->ctrl_out_desc;
+		hs_ep->desc_list_dma = hsotg->ctrl_out_desc_dma;
+		break;
+	default:
+		dev_err(hsotg->dev, "invalid EP 0 state in queue %d\n",
+			hsotg->ep0_state);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int dwc2_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req,
+			       gfp_t gfp_flags)
+{
+	struct dwc2_hsotg_req *hs_req = our_req(req);
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+	bool first;
+	int ret;
+	u32 maxsize = 0;
+	u32 mask = 0;
+
+
+	dev_dbg(hs->dev, "%s: req %p: %d@%p, noi=%d, zero=%d, snok=%d\n",
+		ep->name, req, req->length, req->buf, req->no_interrupt,
+		req->zero, req->short_not_ok);
+
+	/* Prevent new request submission when controller is suspended */
+	if (hs->lx_state != DWC2_L0) {
+		dev_dbg(hs->dev, "%s: submit request only in active state\n",
+			__func__);
+		return -EAGAIN;
+	}
+
+	/* initialise status of the request */
+	INIT_LIST_HEAD(&hs_req->queue);
+	req->actual = 0;
+	req->status = -EINPROGRESS;
+
+	/* Don't queue ISOC request if length greater than mps*mc */
+	if (hs_ep->isochronous &&
+	    req->length > (hs_ep->mc * hs_ep->ep.maxpacket)) {
+		dev_err(hs->dev, "req length > maxpacket*mc\n");
+		return -EINVAL;
+	}
+
+	/* In DDMA mode for ISOC's don't queue request if length greater
+	 * than descriptor limits.
+	 */
+	if (using_desc_dma(hs) && hs_ep->isochronous) {
+		maxsize = dwc2_gadget_get_desc_params(hs_ep, &mask);
+		if (hs_ep->dir_in && req->length > maxsize) {
+			dev_err(hs->dev, "wrong length %d (maxsize=%d)\n",
+				req->length, maxsize);
+			return -EINVAL;
+		}
+
+		if (!hs_ep->dir_in && req->length > hs_ep->ep.maxpacket) {
+			dev_err(hs->dev, "ISOC OUT: wrong length %d (mps=%d)\n",
+				req->length, hs_ep->ep.maxpacket);
+			return -EINVAL;
+		}
+	}
+
+	ret = dwc2_hsotg_handle_unaligned_buf_start(hs, hs_ep, hs_req);
+	if (ret)
+		return ret;
+
+	/* if we're using DMA, sync the buffers as necessary */
+	if (using_dma(hs)) {
+		ret = dwc2_hsotg_map_dma(hs, hs_ep, req);
+		if (ret)
+			return ret;
+	}
+	/* If using descriptor DMA configure EP0 descriptor chain pointers */
+	if (using_desc_dma(hs) && !hs_ep->index) {
+		ret = dwc2_gadget_set_ep0_desc_chain(hs, hs_ep);
+		if (ret)
+			return ret;
+	}
+
+	first = list_empty(&hs_ep->queue);
+	list_add_tail(&hs_req->queue, &hs_ep->queue);
+
+	/*
+	 * Handle DDMA isochronous transfers separately - just add new entry
+	 * to the descriptor chain.
+	 * Transfer will be started once SW gets either one of NAK or
+	 * OutTknEpDis interrupts.
+	 */
+	if (using_desc_dma(hs) && hs_ep->isochronous) {
+		if (hs_ep->target_frame != TARGET_FRAME_INITIAL) {
+			dma_addr_t dma_addr = hs_req->req.dma;
+
+			if (hs_req->req.num_sgs) {
+				WARN_ON(hs_req->req.num_sgs > 1);
+				dma_addr = sg_dma_address(hs_req->req.sg);
+			}
+			dwc2_gadget_fill_isoc_desc(hs_ep, dma_addr,
+						   hs_req->req.length);
+		}
+		return 0;
+	}
+
+	/* Change EP direction if status phase request is after data out */
+	if (!hs_ep->index && !req->length && !hs_ep->dir_in &&
+	    hs->ep0_state == DWC2_EP0_DATA_OUT)
+		hs_ep->dir_in = 1;
+
+	if (first) {
+		if (!hs_ep->isochronous) {
+			dwc2_hsotg_start_req(hs, hs_ep, hs_req, false);
+			return 0;
+		}
+
+		/* Update current frame number value. */
+		hs->frame_number = dwc2_hsotg_read_frameno(hs);
+		while (dwc2_gadget_target_frame_elapsed(hs_ep)) {
+			dwc2_gadget_incr_frame_num(hs_ep);
+			/* Update current frame number value once more as it
+			 * changes here.
+			 */
+			hs->frame_number = dwc2_hsotg_read_frameno(hs);
+		}
+
+		if (hs_ep->target_frame != TARGET_FRAME_INITIAL)
+			dwc2_hsotg_start_req(hs, hs_ep, hs_req, false);
+	}
+	return 0;
+}
+
+static int dwc2_hsotg_ep_queue_lock(struct usb_ep *ep, struct usb_request *req,
+				    gfp_t gfp_flags)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&hs->lock, flags);
+	ret = dwc2_hsotg_ep_queue(ep, req, gfp_flags);
+	spin_unlock_irqrestore(&hs->lock, flags);
+
+	return ret;
+}
+
+static void dwc2_hsotg_ep_free_request(struct usb_ep *ep,
+				       struct usb_request *req)
+{
+	struct dwc2_hsotg_req *hs_req = our_req(req);
+
+	kfree(hs_req);
+}
+
+/**
+ * dwc2_hsotg_complete_oursetup - setup completion callback
+ * @ep: The endpoint the request was on.
+ * @req: The request completed.
+ *
+ * Called on completion of any requests the driver itself
+ * submitted that need cleaning up.
+ */
+static void dwc2_hsotg_complete_oursetup(struct usb_ep *ep,
+					 struct usb_request *req)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+
+	dev_dbg(hsotg->dev, "%s: ep %p, req %p\n", __func__, ep, req);
+
+	dwc2_hsotg_ep_free_request(ep, req);
+}
+
+/**
+ * ep_from_windex - convert control wIndex value to endpoint
+ * @hsotg: The driver state.
+ * @windex: The control request wIndex field (in host order).
+ *
+ * Convert the given wIndex into a pointer to an driver endpoint
+ * structure, or return NULL if it is not a valid endpoint.
+ */
+static struct dwc2_hsotg_ep *ep_from_windex(struct dwc2_hsotg *hsotg,
+					    u32 windex)
+{
+	int dir = (windex & USB_DIR_IN) ? 1 : 0;
+	int idx = windex & 0x7F;
+
+	if (windex >= 0x100)
+		return NULL;
+
+	if (idx > hsotg->num_of_eps)
+		return NULL;
+
+	return index_to_ep(hsotg, idx, dir);
+}
+
+/**
+ * dwc2_hsotg_set_test_mode - Enable usb Test Modes
+ * @hsotg: The driver state.
+ * @testmode: requested usb test mode
+ * Enable usb Test Mode requested by the Host.
+ */
+int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode)
+{
+	int dctl = dwc2_readl(hsotg, DCTL);
+
+	dctl &= ~DCTL_TSTCTL_MASK;
+	switch (testmode) {
+	case USB_TEST_J:
+	case USB_TEST_K:
+	case USB_TEST_SE0_NAK:
+	case USB_TEST_PACKET:
+	case USB_TEST_FORCE_ENABLE:
+		dctl |= testmode << DCTL_TSTCTL_SHIFT;
+		break;
+	default:
+		return -EINVAL;
+	}
+	dwc2_writel(hsotg, dctl, DCTL);
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_send_reply - send reply to control request
+ * @hsotg: The device state
+ * @ep: Endpoint 0
+ * @buff: Buffer for request
+ * @length: Length of reply.
+ *
+ * Create a request and queue it on the given endpoint. This is useful as
+ * an internal method of sending replies to certain control requests, etc.
+ */
+static int dwc2_hsotg_send_reply(struct dwc2_hsotg *hsotg,
+				 struct dwc2_hsotg_ep *ep,
+				void *buff,
+				int length)
+{
+	struct usb_request *req;
+	int ret;
+
+	dev_dbg(hsotg->dev, "%s: buff %p, len %d\n", __func__, buff, length);
+
+	req = dwc2_hsotg_ep_alloc_request(&ep->ep, GFP_ATOMIC);
+	hsotg->ep0_reply = req;
+	if (!req) {
+		dev_warn(hsotg->dev, "%s: cannot alloc req\n", __func__);
+		return -ENOMEM;
+	}
+
+	req->buf = hsotg->ep0_buff;
+	req->length = length;
+	/*
+	 * zero flag is for sending zlp in DATA IN stage. It has no impact on
+	 * STATUS stage.
+	 */
+	req->zero = 0;
+	req->complete = dwc2_hsotg_complete_oursetup;
+
+	if (length)
+		memcpy(req->buf, buff, length);
+
+	ret = dwc2_hsotg_ep_queue(&ep->ep, req, GFP_ATOMIC);
+	if (ret) {
+		dev_warn(hsotg->dev, "%s: cannot queue req\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_process_req_status - process request GET_STATUS
+ * @hsotg: The device state
+ * @ctrl: USB control request
+ */
+static int dwc2_hsotg_process_req_status(struct dwc2_hsotg *hsotg,
+					 struct usb_ctrlrequest *ctrl)
+{
+	struct dwc2_hsotg_ep *ep0 = hsotg->eps_out[0];
+	struct dwc2_hsotg_ep *ep;
+	__le16 reply;
+	u16 status;
+	int ret;
+
+	dev_dbg(hsotg->dev, "%s: USB_REQ_GET_STATUS\n", __func__);
+
+	if (!ep0->dir_in) {
+		dev_warn(hsotg->dev, "%s: direction out?\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (ctrl->bRequestType & USB_RECIP_MASK) {
+	case USB_RECIP_DEVICE:
+		status = hsotg->gadget.is_selfpowered <<
+			 USB_DEVICE_SELF_POWERED;
+		status |= hsotg->remote_wakeup_allowed <<
+			  USB_DEVICE_REMOTE_WAKEUP;
+		reply = cpu_to_le16(status);
+		break;
+
+	case USB_RECIP_INTERFACE:
+		/* currently, the data result should be zero */
+		reply = cpu_to_le16(0);
+		break;
+
+	case USB_RECIP_ENDPOINT:
+		ep = ep_from_windex(hsotg, le16_to_cpu(ctrl->wIndex));
+		if (!ep)
+			return -ENOENT;
+
+		reply = cpu_to_le16(ep->halted ? 1 : 0);
+		break;
+
+	default:
+		return 0;
+	}
+
+	if (le16_to_cpu(ctrl->wLength) != 2)
+		return -EINVAL;
+
+	ret = dwc2_hsotg_send_reply(hsotg, ep0, &reply, 2);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to send reply\n", __func__);
+		return ret;
+	}
+
+	return 1;
+}
+
+static int dwc2_hsotg_ep_sethalt(struct usb_ep *ep, int value, bool now);
+
+/**
+ * get_ep_head - return the first request on the endpoint
+ * @hs_ep: The controller endpoint to get
+ *
+ * Get the first request on the endpoint.
+ */
+static struct dwc2_hsotg_req *get_ep_head(struct dwc2_hsotg_ep *hs_ep)
+{
+	return list_first_entry_or_null(&hs_ep->queue, struct dwc2_hsotg_req,
+					queue);
+}
+
+/**
+ * dwc2_gadget_start_next_request - Starts next request from ep queue
+ * @hs_ep: Endpoint structure
+ *
+ * If queue is empty and EP is ISOC-OUT - unmasks OUTTKNEPDIS which is masked
+ * in its handler. Hence we need to unmask it here to be able to do
+ * resynchronization.
+ */
+static void dwc2_gadget_start_next_request(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	int dir_in = hs_ep->dir_in;
+	struct dwc2_hsotg_req *hs_req;
+
+	if (!list_empty(&hs_ep->queue)) {
+		hs_req = get_ep_head(hs_ep);
+		dwc2_hsotg_start_req(hsotg, hs_ep, hs_req, false);
+		return;
+	}
+	if (!hs_ep->isochronous)
+		return;
+
+	if (dir_in) {
+		dev_dbg(hsotg->dev, "%s: No more ISOC-IN requests\n",
+			__func__);
+	} else {
+		dev_dbg(hsotg->dev, "%s: No more ISOC-OUT requests\n",
+			__func__);
+	}
+}
+
+/**
+ * dwc2_hsotg_process_req_feature - process request {SET,CLEAR}_FEATURE
+ * @hsotg: The device state
+ * @ctrl: USB control request
+ */
+static int dwc2_hsotg_process_req_feature(struct dwc2_hsotg *hsotg,
+					  struct usb_ctrlrequest *ctrl)
+{
+	struct dwc2_hsotg_ep *ep0 = hsotg->eps_out[0];
+	struct dwc2_hsotg_req *hs_req;
+	bool set = (ctrl->bRequest == USB_REQ_SET_FEATURE);
+	struct dwc2_hsotg_ep *ep;
+	int ret;
+	bool halted;
+	u32 recip;
+	u32 wValue;
+	u32 wIndex;
+
+	dev_dbg(hsotg->dev, "%s: %s_FEATURE\n",
+		__func__, set ? "SET" : "CLEAR");
+
+	wValue = le16_to_cpu(ctrl->wValue);
+	wIndex = le16_to_cpu(ctrl->wIndex);
+	recip = ctrl->bRequestType & USB_RECIP_MASK;
+
+	switch (recip) {
+	case USB_RECIP_DEVICE:
+		switch (wValue) {
+		case USB_DEVICE_REMOTE_WAKEUP:
+			if (set)
+				hsotg->remote_wakeup_allowed = 1;
+			else
+				hsotg->remote_wakeup_allowed = 0;
+			break;
+
+		case USB_DEVICE_TEST_MODE:
+			if ((wIndex & 0xff) != 0)
+				return -EINVAL;
+			if (!set)
+				return -EINVAL;
+
+			hsotg->test_mode = wIndex >> 8;
+			break;
+		default:
+			return -ENOENT;
+		}
+
+		ret = dwc2_hsotg_send_reply(hsotg, ep0, NULL, 0);
+		if (ret) {
+			dev_err(hsotg->dev,
+				"%s: failed to send reply\n", __func__);
+			return ret;
+		}
+		break;
+
+	case USB_RECIP_ENDPOINT:
+		ep = ep_from_windex(hsotg, wIndex);
+		if (!ep) {
+			dev_dbg(hsotg->dev, "%s: no endpoint for 0x%04x\n",
+				__func__, wIndex);
+			return -ENOENT;
+		}
+
+		switch (wValue) {
+		case USB_ENDPOINT_HALT:
+			halted = ep->halted;
+
+			if (!ep->wedged)
+				dwc2_hsotg_ep_sethalt(&ep->ep, set, true);
+
+			ret = dwc2_hsotg_send_reply(hsotg, ep0, NULL, 0);
+			if (ret) {
+				dev_err(hsotg->dev,
+					"%s: failed to send reply\n", __func__);
+				return ret;
+			}
+
+			/*
+			 * we have to complete all requests for ep if it was
+			 * halted, and the halt was cleared by CLEAR_FEATURE
+			 */
+
+			if (!set && halted) {
+				/*
+				 * If we have request in progress,
+				 * then complete it
+				 */
+				if (ep->req) {
+					hs_req = ep->req;
+					ep->req = NULL;
+					list_del_init(&hs_req->queue);
+					if (hs_req->req.complete) {
+						spin_unlock(&hsotg->lock);
+						usb_gadget_giveback_request(
+							&ep->ep, &hs_req->req);
+						spin_lock(&hsotg->lock);
+					}
+				}
+
+				/* If we have pending request, then start it */
+				if (!ep->req)
+					dwc2_gadget_start_next_request(ep);
+			}
+
+			break;
+
+		default:
+			return -ENOENT;
+		}
+		break;
+	default:
+		return -ENOENT;
+	}
+	return 1;
+}
+
+static void dwc2_hsotg_enqueue_setup(struct dwc2_hsotg *hsotg);
+
+/**
+ * dwc2_hsotg_stall_ep0 - stall ep0
+ * @hsotg: The device state
+ *
+ * Set stall for ep0 as response for setup request.
+ */
+static void dwc2_hsotg_stall_ep0(struct dwc2_hsotg *hsotg)
+{
+	struct dwc2_hsotg_ep *ep0 = hsotg->eps_out[0];
+	u32 reg;
+	u32 ctrl;
+
+	dev_dbg(hsotg->dev, "ep0 stall (dir=%d)\n", ep0->dir_in);
+	reg = (ep0->dir_in) ? DIEPCTL0 : DOEPCTL0;
+
+	/*
+	 * DxEPCTL_Stall will be cleared by EP once it has
+	 * taken effect, so no need to clear later.
+	 */
+
+	ctrl = dwc2_readl(hsotg, reg);
+	ctrl |= DXEPCTL_STALL;
+	ctrl |= DXEPCTL_CNAK;
+	dwc2_writel(hsotg, ctrl, reg);
+
+	dev_dbg(hsotg->dev,
+		"written DXEPCTL=0x%08x to %08x (DXEPCTL=0x%08x)\n",
+		ctrl, reg, dwc2_readl(hsotg, reg));
+
+	 /*
+	  * complete won't be called, so we enqueue
+	  * setup request here
+	  */
+	 dwc2_hsotg_enqueue_setup(hsotg);
+}
+
+/**
+ * dwc2_hsotg_process_control - process a control request
+ * @hsotg: The device state
+ * @ctrl: The control request received
+ *
+ * The controller has received the SETUP phase of a control request, and
+ * needs to work out what to do next (and whether to pass it on to the
+ * gadget driver).
+ */
+static void dwc2_hsotg_process_control(struct dwc2_hsotg *hsotg,
+				       struct usb_ctrlrequest *ctrl)
+{
+	struct dwc2_hsotg_ep *ep0 = hsotg->eps_out[0];
+	int ret = 0;
+	u32 dcfg;
+
+	dev_dbg(hsotg->dev,
+		"ctrl Type=%02x, Req=%02x, V=%04x, I=%04x, L=%04x\n",
+		ctrl->bRequestType, ctrl->bRequest, ctrl->wValue,
+		ctrl->wIndex, ctrl->wLength);
+
+	if (ctrl->wLength == 0) {
+		ep0->dir_in = 1;
+		hsotg->ep0_state = DWC2_EP0_STATUS_IN;
+	} else if (ctrl->bRequestType & USB_DIR_IN) {
+		ep0->dir_in = 1;
+		hsotg->ep0_state = DWC2_EP0_DATA_IN;
+	} else {
+		ep0->dir_in = 0;
+		hsotg->ep0_state = DWC2_EP0_DATA_OUT;
+	}
+
+	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
+		switch (ctrl->bRequest) {
+		case USB_REQ_SET_ADDRESS:
+			hsotg->connected = 1;
+			dcfg = dwc2_readl(hsotg, DCFG);
+			dcfg &= ~DCFG_DEVADDR_MASK;
+			dcfg |= (le16_to_cpu(ctrl->wValue) <<
+				 DCFG_DEVADDR_SHIFT) & DCFG_DEVADDR_MASK;
+			dwc2_writel(hsotg, dcfg, DCFG);
+
+			dev_info(hsotg->dev, "new address %d\n", ctrl->wValue);
+
+			ret = dwc2_hsotg_send_reply(hsotg, ep0, NULL, 0);
+			return;
+
+		case USB_REQ_GET_STATUS:
+			ret = dwc2_hsotg_process_req_status(hsotg, ctrl);
+			break;
+
+		case USB_REQ_CLEAR_FEATURE:
+		case USB_REQ_SET_FEATURE:
+			ret = dwc2_hsotg_process_req_feature(hsotg, ctrl);
+			break;
+		}
+	}
+
+	/* as a fallback, try delivering it to the driver to deal with */
+
+	if (ret == 0 && hsotg->driver) {
+		spin_unlock(&hsotg->lock);
+		ret = hsotg->driver->setup(&hsotg->gadget, ctrl);
+		spin_lock(&hsotg->lock);
+		if (ret < 0)
+			dev_dbg(hsotg->dev, "driver->setup() ret %d\n", ret);
+	}
+
+	hsotg->delayed_status = false;
+	if (ret == USB_GADGET_DELAYED_STATUS)
+		hsotg->delayed_status = true;
+
+	/*
+	 * the request is either unhandlable, or is not formatted correctly
+	 * so respond with a STALL for the status stage to indicate failure.
+	 */
+
+	if (ret < 0)
+		dwc2_hsotg_stall_ep0(hsotg);
+}
+
+/**
+ * dwc2_hsotg_complete_setup - completion of a setup transfer
+ * @ep: The endpoint the request was on.
+ * @req: The request completed.
+ *
+ * Called on completion of any requests the driver itself submitted for
+ * EP0 setup packets
+ */
+static void dwc2_hsotg_complete_setup(struct usb_ep *ep,
+				      struct usb_request *req)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+
+	if (req->status < 0) {
+		dev_dbg(hsotg->dev, "%s: failed %d\n", __func__, req->status);
+		return;
+	}
+
+	spin_lock(&hsotg->lock);
+	if (req->actual == 0)
+		dwc2_hsotg_enqueue_setup(hsotg);
+	else
+		dwc2_hsotg_process_control(hsotg, req->buf);
+	spin_unlock(&hsotg->lock);
+}
+
+/**
+ * dwc2_hsotg_enqueue_setup - start a request for EP0 packets
+ * @hsotg: The device state.
+ *
+ * Enqueue a request on EP0 if necessary to received any SETUP packets
+ * received from the host.
+ */
+static void dwc2_hsotg_enqueue_setup(struct dwc2_hsotg *hsotg)
+{
+	struct usb_request *req = hsotg->ctrl_req;
+	struct dwc2_hsotg_req *hs_req = our_req(req);
+	int ret;
+
+	dev_dbg(hsotg->dev, "%s: queueing setup request\n", __func__);
+
+	req->zero = 0;
+	req->length = 8;
+	req->buf = hsotg->ctrl_buff;
+	req->complete = dwc2_hsotg_complete_setup;
+
+	if (!list_empty(&hs_req->queue)) {
+		dev_dbg(hsotg->dev, "%s already queued???\n", __func__);
+		return;
+	}
+
+	hsotg->eps_out[0]->dir_in = 0;
+	hsotg->eps_out[0]->send_zlp = 0;
+	hsotg->ep0_state = DWC2_EP0_SETUP;
+
+	ret = dwc2_hsotg_ep_queue(&hsotg->eps_out[0]->ep, req, GFP_ATOMIC);
+	if (ret < 0) {
+		dev_err(hsotg->dev, "%s: failed queue (%d)\n", __func__, ret);
+		/*
+		 * Don't think there's much we can do other than watch the
+		 * driver fail.
+		 */
+	}
+}
+
+static void dwc2_hsotg_program_zlp(struct dwc2_hsotg *hsotg,
+				   struct dwc2_hsotg_ep *hs_ep)
+{
+	u32 ctrl;
+	u8 index = hs_ep->index;
+	u32 epctl_reg = hs_ep->dir_in ? DIEPCTL(index) : DOEPCTL(index);
+	u32 epsiz_reg = hs_ep->dir_in ? DIEPTSIZ(index) : DOEPTSIZ(index);
+
+	if (hs_ep->dir_in)
+		dev_dbg(hsotg->dev, "Sending zero-length packet on ep%d\n",
+			index);
+	else
+		dev_dbg(hsotg->dev, "Receiving zero-length packet on ep%d\n",
+			index);
+	if (using_desc_dma(hsotg)) {
+		/* Not specific buffer needed for ep0 ZLP */
+		dma_addr_t dma = hs_ep->desc_list_dma;
+
+		if (!index)
+			dwc2_gadget_set_ep0_desc_chain(hsotg, hs_ep);
+
+		dwc2_gadget_config_nonisoc_xfer_ddma(hs_ep, dma, 0);
+	} else {
+		dwc2_writel(hsotg, DXEPTSIZ_MC(1) | DXEPTSIZ_PKTCNT(1) |
+			    DXEPTSIZ_XFERSIZE(0),
+			    epsiz_reg);
+	}
+
+	ctrl = dwc2_readl(hsotg, epctl_reg);
+	ctrl |= DXEPCTL_CNAK;  /* clear NAK set by core */
+	ctrl |= DXEPCTL_EPENA; /* ensure ep enabled */
+	ctrl |= DXEPCTL_USBACTEP;
+	dwc2_writel(hsotg, ctrl, epctl_reg);
+}
+
+/**
+ * dwc2_hsotg_complete_request - complete a request given to us
+ * @hsotg: The device state.
+ * @hs_ep: The endpoint the request was on.
+ * @hs_req: The request to complete.
+ * @result: The result code (0 => Ok, otherwise errno)
+ *
+ * The given request has finished, so call the necessary completion
+ * if it has one and then look to see if we can start a new request
+ * on the endpoint.
+ *
+ * Note, expects the ep to already be locked as appropriate.
+ */
+static void dwc2_hsotg_complete_request(struct dwc2_hsotg *hsotg,
+					struct dwc2_hsotg_ep *hs_ep,
+				       struct dwc2_hsotg_req *hs_req,
+				       int result)
+{
+	if (!hs_req) {
+		dev_dbg(hsotg->dev, "%s: nothing to complete?\n", __func__);
+		return;
+	}
+
+	dev_dbg(hsotg->dev, "complete: ep %p %s, req %p, %d => %p\n",
+		hs_ep, hs_ep->ep.name, hs_req, result, hs_req->req.complete);
+
+	/*
+	 * only replace the status if we've not already set an error
+	 * from a previous transaction
+	 */
+
+	if (hs_req->req.status == -EINPROGRESS)
+		hs_req->req.status = result;
+
+	if (using_dma(hsotg))
+		dwc2_hsotg_unmap_dma(hsotg, hs_ep, hs_req);
+
+	dwc2_hsotg_handle_unaligned_buf_complete(hsotg, hs_ep, hs_req);
+
+	hs_ep->req = NULL;
+	list_del_init(&hs_req->queue);
+
+	/*
+	 * call the complete request with the locks off, just in case the
+	 * request tries to queue more work for this endpoint.
+	 */
+
+	if (hs_req->req.complete) {
+		spin_unlock(&hsotg->lock);
+		usb_gadget_giveback_request(&hs_ep->ep, &hs_req->req);
+		spin_lock(&hsotg->lock);
+	}
+
+	/* In DDMA don't need to proceed to starting of next ISOC request */
+	if (using_desc_dma(hsotg) && hs_ep->isochronous)
+		return;
+
+	/*
+	 * Look to see if there is anything else to do. Note, the completion
+	 * of the previous request may have caused a new request to be started
+	 * so be careful when doing this.
+	 */
+
+	if (!hs_ep->req && result >= 0)
+		dwc2_gadget_start_next_request(hs_ep);
+}
+
+/*
+ * dwc2_gadget_complete_isoc_request_ddma - complete an isoc request in DDMA
+ * @hs_ep: The endpoint the request was on.
+ *
+ * Get first request from the ep queue, determine descriptor on which complete
+ * happened. SW discovers which descriptor currently in use by HW, adjusts
+ * dma_address and calculates index of completed descriptor based on the value
+ * of DEPDMA register. Update actual length of request, giveback to gadget.
+ */
+static void dwc2_gadget_complete_isoc_request_ddma(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	struct dwc2_hsotg_req *hs_req;
+	struct usb_request *ureq;
+	u32 desc_sts;
+	u32 mask;
+
+	desc_sts = hs_ep->desc_list[hs_ep->compl_desc].status;
+
+	/* Process only descriptors with buffer status set to DMA done */
+	while ((desc_sts & DEV_DMA_BUFF_STS_MASK) >>
+		DEV_DMA_BUFF_STS_SHIFT == DEV_DMA_BUFF_STS_DMADONE) {
+
+		hs_req = get_ep_head(hs_ep);
+		if (!hs_req) {
+			dev_warn(hsotg->dev, "%s: ISOC EP queue empty\n", __func__);
+			return;
+		}
+		ureq = &hs_req->req;
+
+		/* Check completion status */
+		if ((desc_sts & DEV_DMA_STS_MASK) >> DEV_DMA_STS_SHIFT ==
+			DEV_DMA_STS_SUCC) {
+			mask = hs_ep->dir_in ? DEV_DMA_ISOC_TX_NBYTES_MASK :
+				DEV_DMA_ISOC_RX_NBYTES_MASK;
+			ureq->actual = ureq->length - ((desc_sts & mask) >>
+				DEV_DMA_ISOC_NBYTES_SHIFT);
+
+			/* Adjust actual len for ISOC Out if len is
+			 * not align of 4
+			 */
+			if (!hs_ep->dir_in && ureq->length & 0x3)
+				ureq->actual += 4 - (ureq->length & 0x3);
+
+			/* Set actual frame number for completed transfers */
+			ureq->frame_number =
+				(desc_sts & DEV_DMA_ISOC_FRNUM_MASK) >>
+				DEV_DMA_ISOC_FRNUM_SHIFT;
+		}
+
+		dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, 0);
+
+		hs_ep->compl_desc++;
+		if (hs_ep->compl_desc > (MAX_DMA_DESC_NUM_HS_ISOC - 1))
+			hs_ep->compl_desc = 0;
+		desc_sts = hs_ep->desc_list[hs_ep->compl_desc].status;
+	}
+}
+
+/*
+ * dwc2_gadget_handle_isoc_bna - handle BNA interrupt for ISOC.
+ * @hs_ep: The isochronous endpoint.
+ *
+ * If EP ISOC OUT then need to flush RX FIFO to remove source of BNA
+ * interrupt. Reset target frame and next_desc to allow to start
+ * ISOC's on NAK interrupt for IN direction or on OUTTKNEPDIS
+ * interrupt for OUT direction.
+ */
+static void dwc2_gadget_handle_isoc_bna(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+
+	if (!hs_ep->dir_in)
+		dwc2_flush_rx_fifo(hsotg);
+	dwc2_hsotg_complete_request(hsotg, hs_ep, get_ep_head(hs_ep), 0);
+
+	hs_ep->target_frame = TARGET_FRAME_INITIAL;
+	hs_ep->next_desc = 0;
+	hs_ep->compl_desc = 0;
+}
+
+/**
+ * dwc2_hsotg_rx_data - receive data from the FIFO for an endpoint
+ * @hsotg: The device state.
+ * @ep_idx: The endpoint index for the data
+ * @size: The size of data in the fifo, in bytes
+ *
+ * The FIFO status shows there is data to read from the FIFO for a given
+ * endpoint, so sort out whether we need to read the data into a request
+ * that has been made for that endpoint.
+ */
+static void dwc2_hsotg_rx_data(struct dwc2_hsotg *hsotg, int ep_idx, int size)
+{
+	struct dwc2_hsotg_ep *hs_ep = hsotg->eps_out[ep_idx];
+	struct dwc2_hsotg_req *hs_req = hs_ep->req;
+	int to_read;
+	int max_req;
+	int read_ptr;
+
+	if (!hs_req) {
+		u32 epctl = dwc2_readl(hsotg, DOEPCTL(ep_idx));
+		int ptr;
+
+		dev_dbg(hsotg->dev,
+			"%s: FIFO %d bytes on ep%d but no req (DXEPCTl=0x%08x)\n",
+			 __func__, size, ep_idx, epctl);
+
+		/* dump the data from the FIFO, we've nothing we can do */
+		for (ptr = 0; ptr < size; ptr += 4)
+			(void)dwc2_readl(hsotg, EPFIFO(ep_idx));
+
+		return;
+	}
+
+	to_read = size;
+	read_ptr = hs_req->req.actual;
+	max_req = hs_req->req.length - read_ptr;
+
+	dev_dbg(hsotg->dev, "%s: read %d/%d, done %d/%d\n",
+		__func__, to_read, max_req, read_ptr, hs_req->req.length);
+
+	if (to_read > max_req) {
+		/*
+		 * more data appeared than we where willing
+		 * to deal with in this request.
+		 */
+
+		/* currently we don't deal this */
+		WARN_ON_ONCE(1);
+	}
+
+	hs_ep->total_data += to_read;
+	hs_req->req.actual += to_read;
+	to_read = DIV_ROUND_UP(to_read, 4);
+
+	/*
+	 * note, we might over-write the buffer end by 3 bytes depending on
+	 * alignment of the data.
+	 */
+	dwc2_readl_rep(hsotg, EPFIFO(ep_idx),
+		       hs_req->req.buf + read_ptr, to_read);
+}
+
+/**
+ * dwc2_hsotg_ep0_zlp - send/receive zero-length packet on control endpoint
+ * @hsotg: The device instance
+ * @dir_in: If IN zlp
+ *
+ * Generate a zero-length IN packet request for terminating a SETUP
+ * transaction.
+ *
+ * Note, since we don't write any data to the TxFIFO, then it is
+ * currently believed that we do not need to wait for any space in
+ * the TxFIFO.
+ */
+static void dwc2_hsotg_ep0_zlp(struct dwc2_hsotg *hsotg, bool dir_in)
+{
+	/* eps_out[0] is used in both directions */
+	hsotg->eps_out[0]->dir_in = dir_in;
+	hsotg->ep0_state = dir_in ? DWC2_EP0_STATUS_IN : DWC2_EP0_STATUS_OUT;
+
+	dwc2_hsotg_program_zlp(hsotg, hsotg->eps_out[0]);
+}
+
+/*
+ * dwc2_gadget_get_xfersize_ddma - get transferred bytes amount from desc
+ * @hs_ep - The endpoint on which transfer went
+ *
+ * Iterate over endpoints descriptor chain and get info on bytes remained
+ * in DMA descriptors after transfer has completed. Used for non isoc EPs.
+ */
+static unsigned int dwc2_gadget_get_xfersize_ddma(struct dwc2_hsotg_ep *hs_ep)
+{
+	const struct usb_endpoint_descriptor *ep_desc = hs_ep->ep.desc;
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	unsigned int bytes_rem = 0;
+	unsigned int bytes_rem_correction = 0;
+	struct dwc2_dma_desc *desc = hs_ep->desc_list;
+	int i;
+	u32 status;
+	u32 mps = hs_ep->ep.maxpacket;
+	int dir_in = hs_ep->dir_in;
+
+	if (!desc)
+		return -EINVAL;
+
+	/* Interrupt OUT EP with mps not multiple of 4 */
+	if (hs_ep->index)
+		if (usb_endpoint_xfer_int(ep_desc) && !dir_in && (mps % 4))
+			bytes_rem_correction = 4 - (mps % 4);
+
+	for (i = 0; i < hs_ep->desc_count; ++i) {
+		status = desc->status;
+		bytes_rem += status & DEV_DMA_NBYTES_MASK;
+		bytes_rem -= bytes_rem_correction;
+
+		if (status & DEV_DMA_STS_MASK)
+			dev_err(hsotg->dev, "descriptor %d closed with %x\n",
+				i, status & DEV_DMA_STS_MASK);
+
+		if (status & DEV_DMA_L)
+			break;
+
+		desc++;
+	}
+
+	return bytes_rem;
+}
+
+/**
+ * dwc2_hsotg_handle_outdone - handle receiving OutDone/SetupDone from RXFIFO
+ * @hsotg: The device instance
+ * @epnum: The endpoint received from
+ *
+ * The RXFIFO has delivered an OutDone event, which means that the data
+ * transfer for an OUT endpoint has been completed, either by a short
+ * packet or by the finish of a transfer.
+ */
+static void dwc2_hsotg_handle_outdone(struct dwc2_hsotg *hsotg, int epnum)
+{
+	u32 epsize = dwc2_readl(hsotg, DOEPTSIZ(epnum));
+	struct dwc2_hsotg_ep *hs_ep = hsotg->eps_out[epnum];
+	struct dwc2_hsotg_req *hs_req = hs_ep->req;
+	struct usb_request *req = &hs_req->req;
+	unsigned int size_left = DXEPTSIZ_XFERSIZE_GET(epsize);
+	int result = 0;
+
+	if (!hs_req) {
+		dev_dbg(hsotg->dev, "%s: no request active\n", __func__);
+		return;
+	}
+
+	if (epnum == 0 && hsotg->ep0_state == DWC2_EP0_STATUS_OUT) {
+		dev_dbg(hsotg->dev, "zlp packet received\n");
+		dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, 0);
+		dwc2_hsotg_enqueue_setup(hsotg);
+		return;
+	}
+
+	if (using_desc_dma(hsotg))
+		size_left = dwc2_gadget_get_xfersize_ddma(hs_ep);
+
+	if (using_dma(hsotg)) {
+		unsigned int size_done;
+
+		/*
+		 * Calculate the size of the transfer by checking how much
+		 * is left in the endpoint size register and then working it
+		 * out from the amount we loaded for the transfer.
+		 *
+		 * We need to do this as DMA pointers are always 32bit aligned
+		 * so may overshoot/undershoot the transfer.
+		 */
+
+		size_done = hs_ep->size_loaded - size_left;
+		size_done += hs_ep->last_load;
+
+		req->actual = size_done;
+	}
+
+	/* if there is more request to do, schedule new transfer */
+	if (req->actual < req->length && size_left == 0) {
+		dwc2_hsotg_start_req(hsotg, hs_ep, hs_req, true);
+		return;
+	}
+
+	if (req->actual < req->length && req->short_not_ok) {
+		dev_dbg(hsotg->dev, "%s: got %d/%d (short not ok) => error\n",
+			__func__, req->actual, req->length);
+
+		/*
+		 * todo - what should we return here? there's no one else
+		 * even bothering to check the status.
+		 */
+	}
+
+	/* DDMA IN status phase will start from StsPhseRcvd interrupt */
+	if (!using_desc_dma(hsotg) && epnum == 0 &&
+	    hsotg->ep0_state == DWC2_EP0_DATA_OUT) {
+		/* Move to STATUS IN */
+		if (!hsotg->delayed_status)
+			dwc2_hsotg_ep0_zlp(hsotg, true);
+	}
+
+	/* Set actual frame number for completed transfers */
+	if (!using_desc_dma(hsotg) && hs_ep->isochronous) {
+		req->frame_number = hs_ep->target_frame;
+		dwc2_gadget_incr_frame_num(hs_ep);
+	}
+
+	dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, result);
+}
+
+/**
+ * dwc2_hsotg_handle_rx - RX FIFO has data
+ * @hsotg: The device instance
+ *
+ * The IRQ handler has detected that the RX FIFO has some data in it
+ * that requires processing, so find out what is in there and do the
+ * appropriate read.
+ *
+ * The RXFIFO is a true FIFO, the packets coming out are still in packet
+ * chunks, so if you have x packets received on an endpoint you'll get x
+ * FIFO events delivered, each with a packet's worth of data in it.
+ *
+ * When using DMA, we should not be processing events from the RXFIFO
+ * as the actual data should be sent to the memory directly and we turn
+ * on the completion interrupts to get notifications of transfer completion.
+ */
+static void dwc2_hsotg_handle_rx(struct dwc2_hsotg *hsotg)
+{
+	u32 grxstsr = dwc2_readl(hsotg, GRXSTSP);
+	u32 epnum, status, size;
+
+	WARN_ON(using_dma(hsotg));
+
+	epnum = grxstsr & GRXSTS_EPNUM_MASK;
+	status = grxstsr & GRXSTS_PKTSTS_MASK;
+
+	size = grxstsr & GRXSTS_BYTECNT_MASK;
+	size >>= GRXSTS_BYTECNT_SHIFT;
+
+	dev_dbg(hsotg->dev, "%s: GRXSTSP=0x%08x (%d@%d)\n",
+		__func__, grxstsr, size, epnum);
+
+	switch ((status & GRXSTS_PKTSTS_MASK) >> GRXSTS_PKTSTS_SHIFT) {
+	case GRXSTS_PKTSTS_GLOBALOUTNAK:
+		dev_dbg(hsotg->dev, "GLOBALOUTNAK\n");
+		break;
+
+	case GRXSTS_PKTSTS_OUTDONE:
+		dev_dbg(hsotg->dev, "OutDone (Frame=0x%08x)\n",
+			dwc2_hsotg_read_frameno(hsotg));
+
+		if (!using_dma(hsotg))
+			dwc2_hsotg_handle_outdone(hsotg, epnum);
+		break;
+
+	case GRXSTS_PKTSTS_SETUPDONE:
+		dev_dbg(hsotg->dev,
+			"SetupDone (Frame=0x%08x, DOPEPCTL=0x%08x)\n",
+			dwc2_hsotg_read_frameno(hsotg),
+			dwc2_readl(hsotg, DOEPCTL(0)));
+		/*
+		 * Call dwc2_hsotg_handle_outdone here if it was not called from
+		 * GRXSTS_PKTSTS_OUTDONE. That is, if the core didn't
+		 * generate GRXSTS_PKTSTS_OUTDONE for setup packet.
+		 */
+		if (hsotg->ep0_state == DWC2_EP0_SETUP)
+			dwc2_hsotg_handle_outdone(hsotg, epnum);
+		break;
+
+	case GRXSTS_PKTSTS_OUTRX:
+		dwc2_hsotg_rx_data(hsotg, epnum, size);
+		break;
+
+	case GRXSTS_PKTSTS_SETUPRX:
+		dev_dbg(hsotg->dev,
+			"SetupRX (Frame=0x%08x, DOPEPCTL=0x%08x)\n",
+			dwc2_hsotg_read_frameno(hsotg),
+			dwc2_readl(hsotg, DOEPCTL(0)));
+
+		WARN_ON(hsotg->ep0_state != DWC2_EP0_SETUP);
+
+		dwc2_hsotg_rx_data(hsotg, epnum, size);
+		break;
+
+	default:
+		dev_warn(hsotg->dev, "%s: unknown status %08x\n",
+			 __func__, grxstsr);
+
+		dwc2_hsotg_dump(hsotg);
+		break;
+	}
+}
+
+/**
+ * dwc2_hsotg_ep0_mps - turn max packet size into register setting
+ * @mps: The maximum packet size in bytes.
+ */
+static u32 dwc2_hsotg_ep0_mps(unsigned int mps)
+{
+	switch (mps) {
+	case 64:
+		return D0EPCTL_MPS_64;
+	case 32:
+		return D0EPCTL_MPS_32;
+	case 16:
+		return D0EPCTL_MPS_16;
+	case 8:
+		return D0EPCTL_MPS_8;
+	}
+
+	/* bad max packet size, warn and return invalid result */
+	WARN_ON(1);
+	return (u32)-1;
+}
+
+/**
+ * dwc2_hsotg_set_ep_maxpacket - set endpoint's max-packet field
+ * @hsotg: The driver state.
+ * @ep: The index number of the endpoint
+ * @mps: The maximum packet size in bytes
+ * @mc: The multicount value
+ * @dir_in: True if direction is in.
+ *
+ * Configure the maximum packet size for the given endpoint, updating
+ * the hardware control registers to reflect this.
+ */
+static void dwc2_hsotg_set_ep_maxpacket(struct dwc2_hsotg *hsotg,
+					unsigned int ep, unsigned int mps,
+					unsigned int mc, unsigned int dir_in)
+{
+	struct dwc2_hsotg_ep *hs_ep;
+	u32 reg;
+
+	hs_ep = index_to_ep(hsotg, ep, dir_in);
+	if (!hs_ep)
+		return;
+
+	if (ep == 0) {
+		u32 mps_bytes = mps;
+
+		/* EP0 is a special case */
+		mps = dwc2_hsotg_ep0_mps(mps_bytes);
+		if (mps > 3)
+			goto bad_mps;
+		hs_ep->ep.maxpacket = mps_bytes;
+		hs_ep->mc = 1;
+	} else {
+		if (mps > 1024)
+			goto bad_mps;
+		hs_ep->mc = mc;
+		if (mc > 3)
+			goto bad_mps;
+		hs_ep->ep.maxpacket = mps;
+	}
+
+	if (dir_in) {
+		reg = dwc2_readl(hsotg, DIEPCTL(ep));
+		reg &= ~DXEPCTL_MPS_MASK;
+		reg |= mps;
+		dwc2_writel(hsotg, reg, DIEPCTL(ep));
+	} else {
+		reg = dwc2_readl(hsotg, DOEPCTL(ep));
+		reg &= ~DXEPCTL_MPS_MASK;
+		reg |= mps;
+		dwc2_writel(hsotg, reg, DOEPCTL(ep));
+	}
+
+	return;
+
+bad_mps:
+	dev_err(hsotg->dev, "ep%d: bad mps of %d\n", ep, mps);
+}
+
+/**
+ * dwc2_hsotg_txfifo_flush - flush Tx FIFO
+ * @hsotg: The driver state
+ * @idx: The index for the endpoint (0..15)
+ */
+static void dwc2_hsotg_txfifo_flush(struct dwc2_hsotg *hsotg, unsigned int idx)
+{
+	dwc2_writel(hsotg, GRSTCTL_TXFNUM(idx) | GRSTCTL_TXFFLSH,
+		    GRSTCTL);
+
+	/* wait until the fifo is flushed */
+	if (dwc2_hsotg_wait_bit_clear(hsotg, GRSTCTL, GRSTCTL_TXFFLSH, 100))
+		dev_warn(hsotg->dev, "%s: timeout flushing fifo GRSTCTL_TXFFLSH\n",
+			 __func__);
+}
+
+/**
+ * dwc2_hsotg_trytx - check to see if anything needs transmitting
+ * @hsotg: The driver state
+ * @hs_ep: The driver endpoint to check.
+ *
+ * Check to see if there is a request that has data to send, and if so
+ * make an attempt to write data into the FIFO.
+ */
+static int dwc2_hsotg_trytx(struct dwc2_hsotg *hsotg,
+			    struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg_req *hs_req = hs_ep->req;
+
+	if (!hs_ep->dir_in || !hs_req) {
+		/**
+		 * if request is not enqueued, we disable interrupts
+		 * for endpoints, excepting ep0
+		 */
+		if (hs_ep->index != 0)
+			dwc2_hsotg_ctrl_epint(hsotg, hs_ep->index,
+					      hs_ep->dir_in, 0);
+		return 0;
+	}
+
+	if (hs_req->req.actual < hs_req->req.length) {
+		dev_dbg(hsotg->dev, "trying to write more for ep%d\n",
+			hs_ep->index);
+		return dwc2_hsotg_write_fifo(hsotg, hs_ep, hs_req);
+	}
+
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_complete_in - complete IN transfer
+ * @hsotg: The device state.
+ * @hs_ep: The endpoint that has just completed.
+ *
+ * An IN transfer has been completed, update the transfer's state and then
+ * call the relevant completion routines.
+ */
+static void dwc2_hsotg_complete_in(struct dwc2_hsotg *hsotg,
+				   struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg_req *hs_req = hs_ep->req;
+	u32 epsize = dwc2_readl(hsotg, DIEPTSIZ(hs_ep->index));
+	int size_left, size_done;
+
+	if (!hs_req) {
+		dev_dbg(hsotg->dev, "XferCompl but no req\n");
+		return;
+	}
+
+	/* Finish ZLP handling for IN EP0 transactions */
+	if (hs_ep->index == 0 && hsotg->ep0_state == DWC2_EP0_STATUS_IN) {
+		dev_dbg(hsotg->dev, "zlp packet sent\n");
+
+		/*
+		 * While send zlp for DWC2_EP0_STATUS_IN EP direction was
+		 * changed to IN. Change back to complete OUT transfer request
+		 */
+		hs_ep->dir_in = 0;
+
+		dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, 0);
+		if (hsotg->test_mode) {
+			int ret;
+
+			ret = dwc2_hsotg_set_test_mode(hsotg, hsotg->test_mode);
+			if (ret < 0) {
+				dev_dbg(hsotg->dev, "Invalid Test #%d\n",
+					hsotg->test_mode);
+				dwc2_hsotg_stall_ep0(hsotg);
+				return;
+			}
+		}
+		dwc2_hsotg_enqueue_setup(hsotg);
+		return;
+	}
+
+	/*
+	 * Calculate the size of the transfer by checking how much is left
+	 * in the endpoint size register and then working it out from
+	 * the amount we loaded for the transfer.
+	 *
+	 * We do this even for DMA, as the transfer may have incremented
+	 * past the end of the buffer (DMA transfers are always 32bit
+	 * aligned).
+	 */
+	if (using_desc_dma(hsotg)) {
+		size_left = dwc2_gadget_get_xfersize_ddma(hs_ep);
+		if (size_left < 0)
+			dev_err(hsotg->dev, "error parsing DDMA results %d\n",
+				size_left);
+	} else {
+		size_left = DXEPTSIZ_XFERSIZE_GET(epsize);
+	}
+
+	size_done = hs_ep->size_loaded - size_left;
+	size_done += hs_ep->last_load;
+
+	if (hs_req->req.actual != size_done)
+		dev_dbg(hsotg->dev, "%s: adjusting size done %d => %d\n",
+			__func__, hs_req->req.actual, size_done);
+
+	hs_req->req.actual = size_done;
+	dev_dbg(hsotg->dev, "req->length:%d req->actual:%d req->zero:%d\n",
+		hs_req->req.length, hs_req->req.actual, hs_req->req.zero);
+
+	if (!size_left && hs_req->req.actual < hs_req->req.length) {
+		dev_dbg(hsotg->dev, "%s trying more for req...\n", __func__);
+		dwc2_hsotg_start_req(hsotg, hs_ep, hs_req, true);
+		return;
+	}
+
+	/* Zlp for all endpoints in non DDMA, for ep0 only in DATA IN stage */
+	if (hs_ep->send_zlp) {
+		hs_ep->send_zlp = 0;
+		if (!using_desc_dma(hsotg)) {
+			dwc2_hsotg_program_zlp(hsotg, hs_ep);
+			/* transfer will be completed on next complete interrupt */
+			return;
+		}
+	}
+
+	if (hs_ep->index == 0 && hsotg->ep0_state == DWC2_EP0_DATA_IN) {
+		/* Move to STATUS OUT */
+		dwc2_hsotg_ep0_zlp(hsotg, false);
+		return;
+	}
+
+	/* Set actual frame number for completed transfers */
+	if (!using_desc_dma(hsotg) && hs_ep->isochronous) {
+		hs_req->req.frame_number = hs_ep->target_frame;
+		dwc2_gadget_incr_frame_num(hs_ep);
+	}
+
+	dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, 0);
+}
+
+/**
+ * dwc2_gadget_read_ep_interrupts - reads interrupts for given ep
+ * @hsotg: The device state.
+ * @idx: Index of ep.
+ * @dir_in: Endpoint direction 1-in 0-out.
+ *
+ * Reads for endpoint with given index and direction, by masking
+ * epint_reg with coresponding mask.
+ */
+static u32 dwc2_gadget_read_ep_interrupts(struct dwc2_hsotg *hsotg,
+					  unsigned int idx, int dir_in)
+{
+	u32 epmsk_reg = dir_in ? DIEPMSK : DOEPMSK;
+	u32 epint_reg = dir_in ? DIEPINT(idx) : DOEPINT(idx);
+	u32 ints;
+	u32 mask;
+	u32 diepempmsk;
+
+	mask = dwc2_readl(hsotg, epmsk_reg);
+	diepempmsk = dwc2_readl(hsotg, DIEPEMPMSK);
+	mask |= ((diepempmsk >> idx) & 0x1) ? DIEPMSK_TXFIFOEMPTY : 0;
+	mask |= DXEPINT_SETUP_RCVD;
+
+	ints = dwc2_readl(hsotg, epint_reg);
+	ints &= mask;
+	return ints;
+}
+
+/**
+ * dwc2_gadget_handle_ep_disabled - handle DXEPINT_EPDISBLD
+ * @hs_ep: The endpoint on which interrupt is asserted.
+ *
+ * This interrupt indicates that the endpoint has been disabled per the
+ * application's request.
+ *
+ * For IN endpoints flushes txfifo, in case of BULK clears DCTL_CGNPINNAK,
+ * in case of ISOC completes current request.
+ *
+ * For ISOC-OUT endpoints completes expired requests. If there is remaining
+ * request starts it.
+ */
+static void dwc2_gadget_handle_ep_disabled(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	struct dwc2_hsotg_req *hs_req;
+	unsigned char idx = hs_ep->index;
+	int dir_in = hs_ep->dir_in;
+	u32 epctl_reg = dir_in ? DIEPCTL(idx) : DOEPCTL(idx);
+	int dctl = dwc2_readl(hsotg, DCTL);
+
+	dev_dbg(hsotg->dev, "%s: EPDisbld\n", __func__);
+
+	if (dir_in) {
+		int epctl = dwc2_readl(hsotg, epctl_reg);
+
+		dwc2_hsotg_txfifo_flush(hsotg, hs_ep->fifo_index);
+
+		if ((epctl & DXEPCTL_STALL) && (epctl & DXEPCTL_EPTYPE_BULK)) {
+			int dctl = dwc2_readl(hsotg, DCTL);
+
+			dctl |= DCTL_CGNPINNAK;
+			dwc2_writel(hsotg, dctl, DCTL);
+		}
+	} else {
+
+		if (dctl & DCTL_GOUTNAKSTS) {
+			dctl |= DCTL_CGOUTNAK;
+			dwc2_writel(hsotg, dctl, DCTL);
+		}
+	}
+
+	if (!hs_ep->isochronous)
+		return;
+
+	if (list_empty(&hs_ep->queue)) {
+		dev_dbg(hsotg->dev, "%s: complete_ep 0x%p, ep->queue empty!\n",
+			__func__, hs_ep);
+		return;
+	}
+
+	do {
+		hs_req = get_ep_head(hs_ep);
+		if (hs_req) {
+			hs_req->req.frame_number = hs_ep->target_frame;
+			hs_req->req.actual = 0;
+			dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req,
+						    -ENODATA);
+		}
+		dwc2_gadget_incr_frame_num(hs_ep);
+		/* Update current frame number value. */
+		hsotg->frame_number = dwc2_hsotg_read_frameno(hsotg);
+	} while (dwc2_gadget_target_frame_elapsed(hs_ep));
+}
+
+/**
+ * dwc2_gadget_handle_out_token_ep_disabled - handle DXEPINT_OUTTKNEPDIS
+ * @ep: The endpoint on which interrupt is asserted.
+ *
+ * This is starting point for ISOC-OUT transfer, synchronization done with
+ * first out token received from host while corresponding EP is disabled.
+ *
+ * Device does not know initial frame in which out token will come. For this
+ * HW generates OUTTKNEPDIS - out token is received while EP is disabled. Upon
+ * getting this interrupt SW starts calculation for next transfer frame.
+ */
+static void dwc2_gadget_handle_out_token_ep_disabled(struct dwc2_hsotg_ep *ep)
+{
+	struct dwc2_hsotg *hsotg = ep->parent;
+	struct dwc2_hsotg_req *hs_req;
+	int dir_in = ep->dir_in;
+
+	if (dir_in || !ep->isochronous)
+		return;
+
+	if (using_desc_dma(hsotg)) {
+		if (ep->target_frame == TARGET_FRAME_INITIAL) {
+			/* Start first ISO Out */
+			ep->target_frame = hsotg->frame_number;
+			dwc2_gadget_start_isoc_ddma(ep);
+		}
+		return;
+	}
+
+	if (ep->target_frame == TARGET_FRAME_INITIAL) {
+		u32 ctrl;
+
+		ep->target_frame = hsotg->frame_number;
+		if (ep->interval > 1) {
+			ctrl = dwc2_readl(hsotg, DOEPCTL(ep->index));
+			if (ep->target_frame & 0x1)
+				ctrl |= DXEPCTL_SETODDFR;
+			else
+				ctrl |= DXEPCTL_SETEVENFR;
+
+			dwc2_writel(hsotg, ctrl, DOEPCTL(ep->index));
+		}
+	}
+
+	while (dwc2_gadget_target_frame_elapsed(ep)) {
+		hs_req = get_ep_head(ep);
+		if (hs_req) {
+			hs_req->req.frame_number = ep->target_frame;
+			hs_req->req.actual = 0;
+			dwc2_hsotg_complete_request(hsotg, ep, hs_req, -ENODATA);
+		}
+
+		dwc2_gadget_incr_frame_num(ep);
+		/* Update current frame number value. */
+		hsotg->frame_number = dwc2_hsotg_read_frameno(hsotg);
+	}
+
+	if (!ep->req)
+		dwc2_gadget_start_next_request(ep);
+
+}
+
+static void dwc2_hsotg_ep_stop_xfr(struct dwc2_hsotg *hsotg,
+				   struct dwc2_hsotg_ep *hs_ep);
+
+/**
+ * dwc2_gadget_handle_nak - handle NAK interrupt
+ * @hs_ep: The endpoint on which interrupt is asserted.
+ *
+ * This is starting point for ISOC-IN transfer, synchronization done with
+ * first IN token received from host while corresponding EP is disabled.
+ *
+ * Device does not know when first one token will arrive from host. On first
+ * token arrival HW generates 2 interrupts: 'in token received while FIFO empty'
+ * and 'NAK'. NAK interrupt for ISOC-IN means that token has arrived and ZLP was
+ * sent in response to that as there was no data in FIFO. SW is basing on this
+ * interrupt to obtain frame in which token has come and then based on the
+ * interval calculates next frame for transfer.
+ */
+static void dwc2_gadget_handle_nak(struct dwc2_hsotg_ep *hs_ep)
+{
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	struct dwc2_hsotg_req *hs_req;
+	int dir_in = hs_ep->dir_in;
+	u32 ctrl;
+
+	if (!dir_in || !hs_ep->isochronous)
+		return;
+
+	if (hs_ep->target_frame == TARGET_FRAME_INITIAL) {
+
+		if (using_desc_dma(hsotg)) {
+			hs_ep->target_frame = hsotg->frame_number;
+			dwc2_gadget_incr_frame_num(hs_ep);
+
+			/* In service interval mode target_frame must
+			 * be set to last (u)frame of the service interval.
+			 */
+			if (hsotg->params.service_interval) {
+				/* Set target_frame to the first (u)frame of
+				 * the service interval
+				 */
+				hs_ep->target_frame &= ~hs_ep->interval + 1;
+
+				/* Set target_frame to the last (u)frame of
+				 * the service interval
+				 */
+				dwc2_gadget_incr_frame_num(hs_ep);
+				dwc2_gadget_dec_frame_num_by_one(hs_ep);
+			}
+
+			dwc2_gadget_start_isoc_ddma(hs_ep);
+			return;
+		}
+
+		hs_ep->target_frame = hsotg->frame_number;
+		if (hs_ep->interval > 1) {
+			u32 ctrl = dwc2_readl(hsotg,
+					      DIEPCTL(hs_ep->index));
+			if (hs_ep->target_frame & 0x1)
+				ctrl |= DXEPCTL_SETODDFR;
+			else
+				ctrl |= DXEPCTL_SETEVENFR;
+
+			dwc2_writel(hsotg, ctrl, DIEPCTL(hs_ep->index));
+		}
+	}
+
+	if (using_desc_dma(hsotg))
+		return;
+
+	ctrl = dwc2_readl(hsotg, DIEPCTL(hs_ep->index));
+	if (ctrl & DXEPCTL_EPENA)
+		dwc2_hsotg_ep_stop_xfr(hsotg, hs_ep);
+	else
+		dwc2_hsotg_txfifo_flush(hsotg, hs_ep->fifo_index);
+
+	while (dwc2_gadget_target_frame_elapsed(hs_ep)) {
+		hs_req = get_ep_head(hs_ep);
+		if (hs_req) {
+			hs_req->req.frame_number = hs_ep->target_frame;
+			hs_req->req.actual = 0;
+			dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, -ENODATA);
+		}
+
+		dwc2_gadget_incr_frame_num(hs_ep);
+		/* Update current frame number value. */
+		hsotg->frame_number = dwc2_hsotg_read_frameno(hsotg);
+	}
+
+	if (!hs_ep->req)
+		dwc2_gadget_start_next_request(hs_ep);
+}
+
+/**
+ * dwc2_hsotg_epint - handle an in/out endpoint interrupt
+ * @hsotg: The driver state
+ * @idx: The index for the endpoint (0..15)
+ * @dir_in: Set if this is an IN endpoint
+ *
+ * Process and clear any interrupt pending for an individual endpoint
+ */
+static void dwc2_hsotg_epint(struct dwc2_hsotg *hsotg, unsigned int idx,
+			     int dir_in)
+{
+	struct dwc2_hsotg_ep *hs_ep = index_to_ep(hsotg, idx, dir_in);
+	u32 epint_reg = dir_in ? DIEPINT(idx) : DOEPINT(idx);
+	u32 epctl_reg = dir_in ? DIEPCTL(idx) : DOEPCTL(idx);
+	u32 epsiz_reg = dir_in ? DIEPTSIZ(idx) : DOEPTSIZ(idx);
+	u32 ints;
+
+	ints = dwc2_gadget_read_ep_interrupts(hsotg, idx, dir_in);
+
+	/* Clear endpoint interrupts */
+	dwc2_writel(hsotg, ints, epint_reg);
+
+	if (!hs_ep) {
+		dev_err(hsotg->dev, "%s:Interrupt for unconfigured ep%d(%s)\n",
+			__func__, idx, dir_in ? "in" : "out");
+		return;
+	}
+
+	dev_dbg(hsotg->dev, "%s: ep%d(%s) DxEPINT=0x%08x\n",
+		__func__, idx, dir_in ? "in" : "out", ints);
+
+	/* Don't process XferCompl interrupt if it is a setup packet */
+	if (idx == 0 && (ints & (DXEPINT_SETUP | DXEPINT_SETUP_RCVD)))
+		ints &= ~DXEPINT_XFERCOMPL;
+
+	/*
+	 * Don't process XferCompl interrupt in DDMA if EP0 is still in SETUP
+	 * stage and xfercomplete was generated without SETUP phase done
+	 * interrupt. SW should parse received setup packet only after host's
+	 * exit from setup phase of control transfer.
+	 */
+	if (using_desc_dma(hsotg) && idx == 0 && !hs_ep->dir_in &&
+	    hsotg->ep0_state == DWC2_EP0_SETUP && !(ints & DXEPINT_SETUP))
+		ints &= ~DXEPINT_XFERCOMPL;
+
+	if (ints & DXEPINT_XFERCOMPL) {
+		dev_dbg(hsotg->dev,
+			"%s: XferCompl: DxEPCTL=0x%08x, DXEPTSIZ=%08x\n",
+			__func__, dwc2_readl(hsotg, epctl_reg),
+			dwc2_readl(hsotg, epsiz_reg));
+
+		/* In DDMA handle isochronous requests separately */
+		if (using_desc_dma(hsotg) && hs_ep->isochronous) {
+			dwc2_gadget_complete_isoc_request_ddma(hs_ep);
+		} else if (dir_in) {
+			/*
+			 * We get OutDone from the FIFO, so we only
+			 * need to look at completing IN requests here
+			 * if operating slave mode
+			 */
+			if (!hs_ep->isochronous || !(ints & DXEPINT_NAKINTRPT))
+				dwc2_hsotg_complete_in(hsotg, hs_ep);
+
+			if (idx == 0 && !hs_ep->req)
+				dwc2_hsotg_enqueue_setup(hsotg);
+		} else if (using_dma(hsotg)) {
+			/*
+			 * We're using DMA, we need to fire an OutDone here
+			 * as we ignore the RXFIFO.
+			 */
+			if (!hs_ep->isochronous || !(ints & DXEPINT_OUTTKNEPDIS))
+				dwc2_hsotg_handle_outdone(hsotg, idx);
+		}
+	}
+
+	if (ints & DXEPINT_EPDISBLD)
+		dwc2_gadget_handle_ep_disabled(hs_ep);
+
+	if (ints & DXEPINT_OUTTKNEPDIS)
+		dwc2_gadget_handle_out_token_ep_disabled(hs_ep);
+
+	if (ints & DXEPINT_NAKINTRPT)
+		dwc2_gadget_handle_nak(hs_ep);
+
+	if (ints & DXEPINT_AHBERR)
+		dev_dbg(hsotg->dev, "%s: AHBErr\n", __func__);
+
+	if (ints & DXEPINT_SETUP) {  /* Setup or Timeout */
+		dev_dbg(hsotg->dev, "%s: Setup/Timeout\n",  __func__);
+
+		if (using_dma(hsotg) && idx == 0) {
+			/*
+			 * this is the notification we've received a
+			 * setup packet. In non-DMA mode we'd get this
+			 * from the RXFIFO, instead we need to process
+			 * the setup here.
+			 */
+
+			if (dir_in)
+				WARN_ON_ONCE(1);
+			else
+				dwc2_hsotg_handle_outdone(hsotg, 0);
+		}
+	}
+
+	if (ints & DXEPINT_STSPHSERCVD) {
+		dev_dbg(hsotg->dev, "%s: StsPhseRcvd\n", __func__);
+
+		/* Safety check EP0 state when STSPHSERCVD asserted */
+		if (hsotg->ep0_state == DWC2_EP0_DATA_OUT) {
+			/* Move to STATUS IN for DDMA */
+			if (using_desc_dma(hsotg)) {
+				if (!hsotg->delayed_status)
+					dwc2_hsotg_ep0_zlp(hsotg, true);
+				else
+				/* In case of 3 stage Control Write with delayed
+				 * status, when Status IN transfer started
+				 * before STSPHSERCVD asserted, NAKSTS bit not
+				 * cleared by CNAK in dwc2_hsotg_start_req()
+				 * function. Clear now NAKSTS to allow complete
+				 * transfer.
+				 */
+					dwc2_set_bit(hsotg, DIEPCTL(0),
+						     DXEPCTL_CNAK);
+			}
+		}
+
+	}
+
+	if (ints & DXEPINT_BACK2BACKSETUP)
+		dev_dbg(hsotg->dev, "%s: B2BSetup/INEPNakEff\n", __func__);
+
+	if (ints & DXEPINT_BNAINTR) {
+		dev_dbg(hsotg->dev, "%s: BNA interrupt\n", __func__);
+		if (hs_ep->isochronous)
+			dwc2_gadget_handle_isoc_bna(hs_ep);
+	}
+
+	if (dir_in && !hs_ep->isochronous) {
+		/* not sure if this is important, but we'll clear it anyway */
+		if (ints & DXEPINT_INTKNTXFEMP) {
+			dev_dbg(hsotg->dev, "%s: ep%d: INTknTXFEmpMsk\n",
+				__func__, idx);
+		}
+
+		/* this probably means something bad is happening */
+		if (ints & DXEPINT_INTKNEPMIS) {
+			dev_warn(hsotg->dev, "%s: ep%d: INTknEP\n",
+				 __func__, idx);
+		}
+
+		/* FIFO has space or is empty (see GAHBCFG) */
+		if (hsotg->dedicated_fifos &&
+		    ints & DXEPINT_TXFEMP) {
+			dev_dbg(hsotg->dev, "%s: ep%d: TxFIFOEmpty\n",
+				__func__, idx);
+			if (!using_dma(hsotg))
+				dwc2_hsotg_trytx(hsotg, hs_ep);
+		}
+	}
+}
+
+/**
+ * dwc2_hsotg_irq_enumdone - Handle EnumDone interrupt (enumeration done)
+ * @hsotg: The device state.
+ *
+ * Handle updating the device settings after the enumeration phase has
+ * been completed.
+ */
+static void dwc2_hsotg_irq_enumdone(struct dwc2_hsotg *hsotg)
+{
+	u32 dsts = dwc2_readl(hsotg, DSTS);
+	int ep0_mps = 0, ep_mps = 8;
+
+	/*
+	 * This should signal the finish of the enumeration phase
+	 * of the USB handshaking, so we should now know what rate
+	 * we connected at.
+	 */
+
+	dev_dbg(hsotg->dev, "EnumDone (DSTS=0x%08x)\n", dsts);
+
+	/*
+	 * note, since we're limited by the size of transfer on EP0, and
+	 * it seems IN transfers must be a even number of packets we do
+	 * not advertise a 64byte MPS on EP0.
+	 */
+
+	/* catch both EnumSpd_FS and EnumSpd_FS48 */
+	switch ((dsts & DSTS_ENUMSPD_MASK) >> DSTS_ENUMSPD_SHIFT) {
+	case DSTS_ENUMSPD_FS:
+	case DSTS_ENUMSPD_FS48:
+		hsotg->gadget.speed = USB_SPEED_FULL;
+		ep0_mps = EP0_MPS_LIMIT;
+		ep_mps = 1023;
+		break;
+
+	case DSTS_ENUMSPD_HS:
+		hsotg->gadget.speed = USB_SPEED_HIGH;
+		ep0_mps = EP0_MPS_LIMIT;
+		ep_mps = 1024;
+		break;
+
+	case DSTS_ENUMSPD_LS:
+		hsotg->gadget.speed = USB_SPEED_LOW;
+		ep0_mps = 8;
+		ep_mps = 8;
+		/*
+		 * note, we don't actually support LS in this driver at the
+		 * moment, and the documentation seems to imply that it isn't
+		 * supported by the PHYs on some of the devices.
+		 */
+		break;
+	}
+	dev_info(hsotg->dev, "new device is %s\n",
+		 usb_speed_string(hsotg->gadget.speed));
+
+	/*
+	 * we should now know the maximum packet size for an
+	 * endpoint, so set the endpoints to a default value.
+	 */
+
+	if (ep0_mps) {
+		int i;
+		/* Initialize ep0 for both in and out directions */
+		dwc2_hsotg_set_ep_maxpacket(hsotg, 0, ep0_mps, 0, 1);
+		dwc2_hsotg_set_ep_maxpacket(hsotg, 0, ep0_mps, 0, 0);
+		for (i = 1; i < hsotg->num_of_eps; i++) {
+			if (hsotg->eps_in[i])
+				dwc2_hsotg_set_ep_maxpacket(hsotg, i, ep_mps,
+							    0, 1);
+			if (hsotg->eps_out[i])
+				dwc2_hsotg_set_ep_maxpacket(hsotg, i, ep_mps,
+							    0, 0);
+		}
+	}
+
+	/* ensure after enumeration our EP0 is active */
+
+	dwc2_hsotg_enqueue_setup(hsotg);
+
+	dev_dbg(hsotg->dev, "EP0: DIEPCTL0=0x%08x, DOEPCTL0=0x%08x\n",
+		dwc2_readl(hsotg, DIEPCTL0),
+		dwc2_readl(hsotg, DOEPCTL0));
+}
+
+/**
+ * kill_all_requests - remove all requests from the endpoint's queue
+ * @hsotg: The device state.
+ * @ep: The endpoint the requests may be on.
+ * @result: The result code to use.
+ *
+ * Go through the requests on the given endpoint and mark them
+ * completed with the given result code.
+ */
+static void kill_all_requests(struct dwc2_hsotg *hsotg,
+			      struct dwc2_hsotg_ep *ep,
+			      int result)
+{
+	unsigned int size;
+
+	ep->req = NULL;
+
+	while (!list_empty(&ep->queue)) {
+		struct dwc2_hsotg_req *req = get_ep_head(ep);
+
+		dwc2_hsotg_complete_request(hsotg, ep, req, result);
+	}
+
+	if (!hsotg->dedicated_fifos)
+		return;
+	size = (dwc2_readl(hsotg, DTXFSTS(ep->fifo_index)) & 0xffff) * 4;
+	if (size < ep->fifo_size)
+		dwc2_hsotg_txfifo_flush(hsotg, ep->fifo_index);
+}
+
+/**
+ * dwc2_hsotg_disconnect - disconnect service
+ * @hsotg: The device state.
+ *
+ * The device has been disconnected. Remove all current
+ * transactions and signal the gadget driver that this
+ * has happened.
+ */
+void dwc2_hsotg_disconnect(struct dwc2_hsotg *hsotg)
+{
+	unsigned int ep;
+
+	if (!hsotg->connected)
+		return;
+
+	hsotg->connected = 0;
+	hsotg->test_mode = 0;
+
+	/* all endpoints should be shutdown */
+	for (ep = 0; ep < hsotg->num_of_eps; ep++) {
+		if (hsotg->eps_in[ep])
+			kill_all_requests(hsotg, hsotg->eps_in[ep],
+					  -ESHUTDOWN);
+		if (hsotg->eps_out[ep])
+			kill_all_requests(hsotg, hsotg->eps_out[ep],
+					  -ESHUTDOWN);
+	}
+
+	call_gadget(hsotg, disconnect);
+	hsotg->lx_state = DWC2_L3;
+
+	usb_gadget_set_state(&hsotg->gadget, USB_STATE_NOTATTACHED);
+}
+
+/**
+ * dwc2_hsotg_irq_fifoempty - TX FIFO empty interrupt handler
+ * @hsotg: The device state:
+ * @periodic: True if this is a periodic FIFO interrupt
+ */
+static void dwc2_hsotg_irq_fifoempty(struct dwc2_hsotg *hsotg, bool periodic)
+{
+	struct dwc2_hsotg_ep *ep;
+	int epno, ret;
+
+	/* look through for any more data to transmit */
+	for (epno = 0; epno < hsotg->num_of_eps; epno++) {
+		ep = index_to_ep(hsotg, epno, 1);
+
+		if (!ep)
+			continue;
+
+		if (!ep->dir_in)
+			continue;
+
+		if ((periodic && !ep->periodic) ||
+		    (!periodic && ep->periodic))
+			continue;
+
+		ret = dwc2_hsotg_trytx(hsotg, ep);
+		if (ret < 0)
+			break;
+	}
+}
+
+/* IRQ flags which will trigger a retry around the IRQ loop */
+#define IRQ_RETRY_MASK (GINTSTS_NPTXFEMP | \
+			GINTSTS_PTXFEMP |  \
+			GINTSTS_RXFLVL)
+
+static int dwc2_hsotg_ep_disable(struct usb_ep *ep);
+/**
+ * dwc2_hsotg_core_init_disconnected - issue softreset to the core
+ * @hsotg: The device state
+ * @is_usb_reset: Usb resetting flag
+ *
+ * Issue a soft reset to the core, and await the core finishing it.
+ */
+void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg,
+				       bool is_usb_reset)
+{
+	u32 intmsk;
+	u32 val;
+	u32 usbcfg;
+	u32 dcfg = 0;
+	int ep;
+
+	/* Kill any ep0 requests as controller will be reinitialized */
+	kill_all_requests(hsotg, hsotg->eps_out[0], -ECONNRESET);
+
+	if (!is_usb_reset) {
+		if (dwc2_core_reset(hsotg, true))
+			return;
+	} else {
+		/* all endpoints should be shutdown */
+		for (ep = 1; ep < hsotg->num_of_eps; ep++) {
+			if (hsotg->eps_in[ep])
+				dwc2_hsotg_ep_disable(&hsotg->eps_in[ep]->ep);
+			if (hsotg->eps_out[ep])
+				dwc2_hsotg_ep_disable(&hsotg->eps_out[ep]->ep);
+		}
+	}
+
+	/*
+	 * we must now enable ep0 ready for host detection and then
+	 * set configuration.
+	 */
+
+	/* keep other bits untouched (so e.g. forced modes are not lost) */
+	usbcfg = dwc2_readl(hsotg, GUSBCFG);
+	usbcfg &= ~GUSBCFG_TOUTCAL_MASK;
+	usbcfg |= GUSBCFG_TOUTCAL(7);
+
+	/* remove the HNP/SRP and set the PHY */
+	usbcfg &= ~(GUSBCFG_SRPCAP | GUSBCFG_HNPCAP);
+        dwc2_writel(hsotg, usbcfg, GUSBCFG);
+
+	dwc2_phy_init(hsotg, true);
+
+	dwc2_hsotg_init_fifo(hsotg);
+
+	if (!is_usb_reset)
+		dwc2_set_bit(hsotg, DCTL, DCTL_SFTDISCON);
+
+	dcfg |= DCFG_EPMISCNT(1);
+
+	switch (hsotg->params.speed) {
+	case DWC2_SPEED_PARAM_LOW:
+		dcfg |= DCFG_DEVSPD_LS;
+		break;
+	case DWC2_SPEED_PARAM_FULL:
+		if (hsotg->params.phy_type == DWC2_PHY_TYPE_PARAM_FS)
+			dcfg |= DCFG_DEVSPD_FS48;
+		else
+			dcfg |= DCFG_DEVSPD_FS;
+		break;
+	default:
+		dcfg |= DCFG_DEVSPD_HS;
+	}
+
+	if (hsotg->params.ipg_isoc_en)
+		dcfg |= DCFG_IPG_ISOC_SUPPORDED;
+
+	dwc2_writel(hsotg, dcfg,  DCFG);
+
+	/* Clear any pending OTG interrupts */
+	dwc2_writel(hsotg, 0xffffffff, GOTGINT);
+
+	/* Clear any pending interrupts */
+	dwc2_writel(hsotg, 0xffffffff, GINTSTS);
+	intmsk = GINTSTS_ERLYSUSP | GINTSTS_SESSREQINT |
+		GINTSTS_GOUTNAKEFF | GINTSTS_GINNAKEFF |
+		GINTSTS_USBRST | GINTSTS_RESETDET |
+		GINTSTS_ENUMDONE | GINTSTS_OTGINT |
+		GINTSTS_USBSUSP | GINTSTS_WKUPINT |
+		GINTSTS_LPMTRANRCVD;
+
+	if (!using_desc_dma(hsotg))
+		intmsk |= GINTSTS_INCOMPL_SOIN | GINTSTS_INCOMPL_SOOUT;
+
+	if (!hsotg->params.external_id_pin_ctl)
+		intmsk |= GINTSTS_CONIDSTSCHNG;
+
+	dwc2_writel(hsotg, intmsk, GINTMSK);
+
+	if (using_dma(hsotg)) {
+		dwc2_writel(hsotg, GAHBCFG_GLBL_INTR_EN | GAHBCFG_DMA_EN |
+			    hsotg->params.ahbcfg,
+			    GAHBCFG);
+
+		/* Set DDMA mode support in the core if needed */
+		if (using_desc_dma(hsotg))
+			dwc2_set_bit(hsotg, DCFG, DCFG_DESCDMA_EN);
+
+	} else {
+		dwc2_writel(hsotg, ((hsotg->dedicated_fifos) ?
+						(GAHBCFG_NP_TXF_EMP_LVL |
+						 GAHBCFG_P_TXF_EMP_LVL) : 0) |
+			    GAHBCFG_GLBL_INTR_EN, GAHBCFG);
+	}
+
+	/*
+	 * If INTknTXFEmpMsk is enabled, it's important to disable ep interrupts
+	 * when we have no data to transfer. Otherwise we get being flooded by
+	 * interrupts.
+	 */
+
+	dwc2_writel(hsotg, ((hsotg->dedicated_fifos && !using_dma(hsotg)) ?
+		DIEPMSK_TXFIFOEMPTY | DIEPMSK_INTKNTXFEMPMSK : 0) |
+		DIEPMSK_EPDISBLDMSK | DIEPMSK_XFERCOMPLMSK |
+		DIEPMSK_TIMEOUTMSK | DIEPMSK_AHBERRMSK,
+		DIEPMSK);
+
+	/*
+	 * don't need XferCompl, we get that from RXFIFO in slave mode. In
+	 * DMA mode we may need this and StsPhseRcvd.
+	 */
+	dwc2_writel(hsotg, (using_dma(hsotg) ? (DIEPMSK_XFERCOMPLMSK |
+		DOEPMSK_STSPHSERCVDMSK) : 0) |
+		DOEPMSK_EPDISBLDMSK | DOEPMSK_AHBERRMSK |
+		DOEPMSK_SETUPMSK,
+		DOEPMSK);
+
+	/* Enable BNA interrupt for DDMA */
+	if (using_desc_dma(hsotg)) {
+		dwc2_set_bit(hsotg, DOEPMSK, DOEPMSK_BNAMSK);
+		dwc2_set_bit(hsotg, DIEPMSK, DIEPMSK_BNAININTRMSK);
+	}
+
+	/* Enable Service Interval mode if supported */
+	if (using_desc_dma(hsotg) && hsotg->params.service_interval)
+		dwc2_set_bit(hsotg, DCTL, DCTL_SERVICE_INTERVAL_SUPPORTED);
+
+	dwc2_writel(hsotg, 0, DAINTMSK);
+
+	dev_dbg(hsotg->dev, "EP0: DIEPCTL0=0x%08x, DOEPCTL0=0x%08x\n",
+		dwc2_readl(hsotg, DIEPCTL0),
+		dwc2_readl(hsotg, DOEPCTL0));
+
+	/* enable in and out endpoint interrupts */
+	dwc2_hsotg_en_gsint(hsotg, GINTSTS_OEPINT | GINTSTS_IEPINT);
+
+	/*
+	 * Enable the RXFIFO when in slave mode, as this is how we collect
+	 * the data. In DMA mode, we get events from the FIFO but also
+	 * things we cannot process, so do not use it.
+	 */
+	if (!using_dma(hsotg))
+		dwc2_hsotg_en_gsint(hsotg, GINTSTS_RXFLVL);
+
+	/* Enable interrupts for EP0 in and out */
+	dwc2_hsotg_ctrl_epint(hsotg, 0, 0, 1);
+	dwc2_hsotg_ctrl_epint(hsotg, 0, 1, 1);
+
+	if (!is_usb_reset) {
+		dwc2_set_bit(hsotg, DCTL, DCTL_PWRONPRGDONE);
+		udelay(10);  /* see openiboot */
+		dwc2_clear_bit(hsotg, DCTL, DCTL_PWRONPRGDONE);
+	}
+
+	dev_dbg(hsotg->dev, "DCTL=0x%08x\n", dwc2_readl(hsotg, DCTL));
+
+	/*
+	 * DxEPCTL_USBActEp says RO in manual, but seems to be set by
+	 * writing to the EPCTL register..
+	 */
+
+	/* set to read 1 8byte packet */
+	dwc2_writel(hsotg, DXEPTSIZ_MC(1) | DXEPTSIZ_PKTCNT(1) |
+	       DXEPTSIZ_XFERSIZE(8), DOEPTSIZ0);
+
+	dwc2_writel(hsotg, dwc2_hsotg_ep0_mps(hsotg->eps_out[0]->ep.maxpacket) |
+	       DXEPCTL_CNAK | DXEPCTL_EPENA |
+	       DXEPCTL_USBACTEP,
+	       DOEPCTL0);
+
+	/* enable, but don't activate EP0in */
+	dwc2_writel(hsotg, dwc2_hsotg_ep0_mps(hsotg->eps_out[0]->ep.maxpacket) |
+	       DXEPCTL_USBACTEP, DIEPCTL0);
+
+	/* clear global NAKs */
+	val = DCTL_CGOUTNAK | DCTL_CGNPINNAK;
+	if (!is_usb_reset)
+		val |= DCTL_SFTDISCON;
+	dwc2_set_bit(hsotg, DCTL, val);
+
+	/* configure the core to support LPM */
+	dwc2_gadget_init_lpm(hsotg);
+
+	/* program GREFCLK register if needed */
+	if (using_desc_dma(hsotg) && hsotg->params.service_interval)
+		dwc2_gadget_program_ref_clk(hsotg);
+
+	/* must be at-least 3ms to allow bus to see disconnect */
+	mdelay(3);
+
+	hsotg->lx_state = DWC2_L0;
+
+	dwc2_hsotg_enqueue_setup(hsotg);
+
+	dev_dbg(hsotg->dev, "EP0: DIEPCTL0=0x%08x, DOEPCTL0=0x%08x\n",
+		dwc2_readl(hsotg, DIEPCTL0),
+		dwc2_readl(hsotg, DOEPCTL0));
+}
+
+void dwc2_hsotg_core_disconnect(struct dwc2_hsotg *hsotg)
+{
+	/* set the soft-disconnect bit */
+	dwc2_set_bit(hsotg, DCTL, DCTL_SFTDISCON);
+}
+
+void dwc2_hsotg_core_connect(struct dwc2_hsotg *hsotg)
+{
+	/* remove the soft-disconnect and let's go */
+	if (!hsotg->role_sw || (dwc2_readl(hsotg, GOTGCTL) & GOTGCTL_BSESVLD))
+		dwc2_clear_bit(hsotg, DCTL, DCTL_SFTDISCON);
+}
+
+/**
+ * dwc2_gadget_handle_incomplete_isoc_in - handle incomplete ISO IN Interrupt.
+ * @hsotg: The device state:
+ *
+ * This interrupt indicates one of the following conditions occurred while
+ * transmitting an ISOC transaction.
+ * - Corrupted IN Token for ISOC EP.
+ * - Packet not complete in FIFO.
+ *
+ * The following actions will be taken:
+ * - Determine the EP
+ * - Disable EP; when 'Endpoint Disabled' interrupt is received Flush FIFO
+ */
+static void dwc2_gadget_handle_incomplete_isoc_in(struct dwc2_hsotg *hsotg)
+{
+	struct dwc2_hsotg_ep *hs_ep;
+	u32 epctrl;
+	u32 daintmsk;
+	u32 idx;
+
+	dev_dbg(hsotg->dev, "Incomplete isoc in interrupt received:\n");
+
+	daintmsk = dwc2_readl(hsotg, DAINTMSK);
+
+	for (idx = 1; idx < hsotg->num_of_eps; idx++) {
+		hs_ep = hsotg->eps_in[idx];
+		/* Proceed only unmasked ISOC EPs */
+		if ((BIT(idx) & ~daintmsk) || !hs_ep->isochronous)
+			continue;
+
+		epctrl = dwc2_readl(hsotg, DIEPCTL(idx));
+		if ((epctrl & DXEPCTL_EPENA) &&
+		    dwc2_gadget_target_frame_elapsed(hs_ep)) {
+			epctrl |= DXEPCTL_SNAK;
+			epctrl |= DXEPCTL_EPDIS;
+			dwc2_writel(hsotg, epctrl, DIEPCTL(idx));
+		}
+	}
+
+	/* Clear interrupt */
+	dwc2_writel(hsotg, GINTSTS_INCOMPL_SOIN, GINTSTS);
+}
+
+/**
+ * dwc2_gadget_handle_incomplete_isoc_out - handle incomplete ISO OUT Interrupt
+ * @hsotg: The device state:
+ *
+ * This interrupt indicates one of the following conditions occurred while
+ * transmitting an ISOC transaction.
+ * - Corrupted OUT Token for ISOC EP.
+ * - Packet not complete in FIFO.
+ *
+ * The following actions will be taken:
+ * - Determine the EP
+ * - Set DCTL_SGOUTNAK and unmask GOUTNAKEFF if target frame elapsed.
+ */
+static void dwc2_gadget_handle_incomplete_isoc_out(struct dwc2_hsotg *hsotg)
+{
+	u32 gintsts;
+	u32 gintmsk;
+	u32 daintmsk;
+	u32 epctrl;
+	struct dwc2_hsotg_ep *hs_ep;
+	int idx;
+
+	dev_dbg(hsotg->dev, "%s: GINTSTS_INCOMPL_SOOUT\n", __func__);
+
+	daintmsk = dwc2_readl(hsotg, DAINTMSK);
+	daintmsk >>= DAINT_OUTEP_SHIFT;
+
+	for (idx = 1; idx < hsotg->num_of_eps; idx++) {
+		hs_ep = hsotg->eps_out[idx];
+		/* Proceed only unmasked ISOC EPs */
+		if ((BIT(idx) & ~daintmsk) || !hs_ep->isochronous)
+			continue;
+
+		epctrl = dwc2_readl(hsotg, DOEPCTL(idx));
+		if ((epctrl & DXEPCTL_EPENA) &&
+		    dwc2_gadget_target_frame_elapsed(hs_ep)) {
+			/* Unmask GOUTNAKEFF interrupt */
+			gintmsk = dwc2_readl(hsotg, GINTMSK);
+			gintmsk |= GINTSTS_GOUTNAKEFF;
+			dwc2_writel(hsotg, gintmsk, GINTMSK);
+
+			gintsts = dwc2_readl(hsotg, GINTSTS);
+			if (!(gintsts & GINTSTS_GOUTNAKEFF)) {
+				dwc2_set_bit(hsotg, DCTL, DCTL_SGOUTNAK);
+				break;
+			}
+		}
+	}
+
+	/* Clear interrupt */
+	dwc2_writel(hsotg, GINTSTS_INCOMPL_SOOUT, GINTSTS);
+}
+
+/**
+ * dwc2_hsotg_irq - handle device interrupt
+ * @irq: The IRQ number triggered
+ * @pw: The pw value when registered the handler.
+ */
+static irqreturn_t dwc2_hsotg_irq(int irq, void *pw)
+{
+	struct dwc2_hsotg *hsotg = pw;
+	int retry_count = 8;
+	u32 gintsts;
+	u32 gintmsk;
+
+	if (!dwc2_is_device_mode(hsotg))
+		return IRQ_NONE;
+
+	spin_lock(&hsotg->lock);
+irq_retry:
+	gintsts = dwc2_readl(hsotg, GINTSTS);
+	gintmsk = dwc2_readl(hsotg, GINTMSK);
+
+	dev_dbg(hsotg->dev, "%s: %08x %08x (%08x) retry %d\n",
+		__func__, gintsts, gintsts & gintmsk, gintmsk, retry_count);
+
+	gintsts &= gintmsk;
+
+	if (gintsts & GINTSTS_RESETDET) {
+		dev_dbg(hsotg->dev, "%s: USBRstDet\n", __func__);
+
+		dwc2_writel(hsotg, GINTSTS_RESETDET, GINTSTS);
+
+		/* This event must be used only if controller is suspended */
+		if (hsotg->in_ppd && hsotg->lx_state == DWC2_L2)
+			dwc2_exit_partial_power_down(hsotg, 0, true);
+
+		hsotg->lx_state = DWC2_L0;
+	}
+
+	if (gintsts & (GINTSTS_USBRST | GINTSTS_RESETDET)) {
+		u32 usb_status = dwc2_readl(hsotg, GOTGCTL);
+		u32 connected = hsotg->connected;
+
+		dev_dbg(hsotg->dev, "%s: USBRst\n", __func__);
+		dev_dbg(hsotg->dev, "GNPTXSTS=%08x\n",
+			dwc2_readl(hsotg, GNPTXSTS));
+
+		dwc2_writel(hsotg, GINTSTS_USBRST, GINTSTS);
+
+		/* Report disconnection if it is not already done. */
+		dwc2_hsotg_disconnect(hsotg);
+
+		/* Reset device address to zero */
+		dwc2_clear_bit(hsotg, DCFG, DCFG_DEVADDR_MASK);
+
+		if (usb_status & GOTGCTL_BSESVLD && connected)
+			dwc2_hsotg_core_init_disconnected(hsotg, true);
+	}
+
+	if (gintsts & GINTSTS_ENUMDONE) {
+		dwc2_writel(hsotg, GINTSTS_ENUMDONE, GINTSTS);
+
+		dwc2_hsotg_irq_enumdone(hsotg);
+	}
+
+	if (gintsts & (GINTSTS_OEPINT | GINTSTS_IEPINT)) {
+		u32 daint = dwc2_readl(hsotg, DAINT);
+		u32 daintmsk = dwc2_readl(hsotg, DAINTMSK);
+		u32 daint_out, daint_in;
+		int ep;
+
+		daint &= daintmsk;
+		daint_out = daint >> DAINT_OUTEP_SHIFT;
+		daint_in = daint & ~(daint_out << DAINT_OUTEP_SHIFT);
+
+		dev_dbg(hsotg->dev, "%s: daint=%08x\n", __func__, daint);
+
+		for (ep = 0; ep < hsotg->num_of_eps && daint_out;
+						ep++, daint_out >>= 1) {
+			if (daint_out & 1)
+				dwc2_hsotg_epint(hsotg, ep, 0);
+		}
+
+		for (ep = 0; ep < hsotg->num_of_eps  && daint_in;
+						ep++, daint_in >>= 1) {
+			if (daint_in & 1)
+				dwc2_hsotg_epint(hsotg, ep, 1);
+		}
+	}
+
+	/* check both FIFOs */
+
+	if (gintsts & GINTSTS_NPTXFEMP) {
+		dev_dbg(hsotg->dev, "NPTxFEmp\n");
+
+		/*
+		 * Disable the interrupt to stop it happening again
+		 * unless one of these endpoint routines decides that
+		 * it needs re-enabling
+		 */
+
+		dwc2_hsotg_disable_gsint(hsotg, GINTSTS_NPTXFEMP);
+		dwc2_hsotg_irq_fifoempty(hsotg, false);
+	}
+
+	if (gintsts & GINTSTS_PTXFEMP) {
+		dev_dbg(hsotg->dev, "PTxFEmp\n");
+
+		/* See note in GINTSTS_NPTxFEmp */
+
+		dwc2_hsotg_disable_gsint(hsotg, GINTSTS_PTXFEMP);
+		dwc2_hsotg_irq_fifoempty(hsotg, true);
+	}
+
+	if (gintsts & GINTSTS_RXFLVL) {
+		/*
+		 * note, since GINTSTS_RxFLvl doubles as FIFO-not-empty,
+		 * we need to retry dwc2_hsotg_handle_rx if this is still
+		 * set.
+		 */
+
+		dwc2_hsotg_handle_rx(hsotg);
+	}
+
+	if (gintsts & GINTSTS_ERLYSUSP) {
+		dev_dbg(hsotg->dev, "GINTSTS_ErlySusp\n");
+		dwc2_writel(hsotg, GINTSTS_ERLYSUSP, GINTSTS);
+	}
+
+	/*
+	 * these next two seem to crop-up occasionally causing the core
+	 * to shutdown the USB transfer, so try clearing them and logging
+	 * the occurrence.
+	 */
+
+	if (gintsts & GINTSTS_GOUTNAKEFF) {
+		u8 idx;
+		u32 epctrl;
+		u32 gintmsk;
+		u32 daintmsk;
+		struct dwc2_hsotg_ep *hs_ep;
+
+		daintmsk = dwc2_readl(hsotg, DAINTMSK);
+		daintmsk >>= DAINT_OUTEP_SHIFT;
+		/* Mask this interrupt */
+		gintmsk = dwc2_readl(hsotg, GINTMSK);
+		gintmsk &= ~GINTSTS_GOUTNAKEFF;
+		dwc2_writel(hsotg, gintmsk, GINTMSK);
+
+		dev_dbg(hsotg->dev, "GOUTNakEff triggered\n");
+		for (idx = 1; idx < hsotg->num_of_eps; idx++) {
+			hs_ep = hsotg->eps_out[idx];
+			/* Proceed only unmasked ISOC EPs */
+			if (BIT(idx) & ~daintmsk)
+				continue;
+
+			epctrl = dwc2_readl(hsotg, DOEPCTL(idx));
+
+			//ISOC Ep's only
+			if ((epctrl & DXEPCTL_EPENA) && hs_ep->isochronous) {
+				epctrl |= DXEPCTL_SNAK;
+				epctrl |= DXEPCTL_EPDIS;
+				dwc2_writel(hsotg, epctrl, DOEPCTL(idx));
+				continue;
+			}
+
+			//Non-ISOC EP's
+			if (hs_ep->halted) {
+				if (!(epctrl & DXEPCTL_EPENA))
+					epctrl |= DXEPCTL_EPENA;
+				epctrl |= DXEPCTL_EPDIS;
+				epctrl |= DXEPCTL_STALL;
+				dwc2_writel(hsotg, epctrl, DOEPCTL(idx));
+			}
+		}
+
+		/* This interrupt bit is cleared in DXEPINT_EPDISBLD handler */
+	}
+
+	if (gintsts & GINTSTS_GINNAKEFF) {
+		dev_info(hsotg->dev, "GINNakEff triggered\n");
+
+		dwc2_set_bit(hsotg, DCTL, DCTL_CGNPINNAK);
+
+		dwc2_hsotg_dump(hsotg);
+	}
+
+	if (gintsts & GINTSTS_INCOMPL_SOIN)
+		dwc2_gadget_handle_incomplete_isoc_in(hsotg);
+
+	if (gintsts & GINTSTS_INCOMPL_SOOUT)
+		dwc2_gadget_handle_incomplete_isoc_out(hsotg);
+
+	/*
+	 * if we've had fifo events, we should try and go around the
+	 * loop again to see if there's any point in returning yet.
+	 */
+
+	if (gintsts & IRQ_RETRY_MASK && --retry_count > 0)
+		goto irq_retry;
+
+	/* Check WKUP_ALERT interrupt*/
+	if (hsotg->params.service_interval)
+		dwc2_gadget_wkup_alert_handler(hsotg);
+
+	spin_unlock(&hsotg->lock);
+
+	return IRQ_HANDLED;
+}
+
+static void dwc2_hsotg_ep_stop_xfr(struct dwc2_hsotg *hsotg,
+				   struct dwc2_hsotg_ep *hs_ep)
+{
+	u32 epctrl_reg;
+	u32 epint_reg;
+
+	epctrl_reg = hs_ep->dir_in ? DIEPCTL(hs_ep->index) :
+		DOEPCTL(hs_ep->index);
+	epint_reg = hs_ep->dir_in ? DIEPINT(hs_ep->index) :
+		DOEPINT(hs_ep->index);
+
+	dev_dbg(hsotg->dev, "%s: stopping transfer on %s\n", __func__,
+		hs_ep->name);
+
+	if (hs_ep->dir_in) {
+		if (hsotg->dedicated_fifos || hs_ep->periodic) {
+			dwc2_set_bit(hsotg, epctrl_reg, DXEPCTL_SNAK);
+			/* Wait for Nak effect */
+			if (dwc2_hsotg_wait_bit_set(hsotg, epint_reg,
+						    DXEPINT_INEPNAKEFF, 100))
+				dev_warn(hsotg->dev,
+					 "%s: timeout DIEPINT.NAKEFF\n",
+					 __func__);
+		} else {
+			dwc2_set_bit(hsotg, DCTL, DCTL_SGNPINNAK);
+			/* Wait for Nak effect */
+			if (dwc2_hsotg_wait_bit_set(hsotg, GINTSTS,
+						    GINTSTS_GINNAKEFF, 100))
+				dev_warn(hsotg->dev,
+					 "%s: timeout GINTSTS.GINNAKEFF\n",
+					 __func__);
+		}
+	} else {
+		/* Mask GINTSTS_GOUTNAKEFF interrupt */
+		dwc2_hsotg_disable_gsint(hsotg, GINTSTS_GOUTNAKEFF);
+
+		if (!(dwc2_readl(hsotg, GINTSTS) & GINTSTS_GOUTNAKEFF))
+			dwc2_set_bit(hsotg, DCTL, DCTL_SGOUTNAK);
+
+		if (!using_dma(hsotg)) {
+			/* Wait for GINTSTS_RXFLVL interrupt */
+			if (dwc2_hsotg_wait_bit_set(hsotg, GINTSTS,
+						    GINTSTS_RXFLVL, 100)) {
+				dev_warn(hsotg->dev, "%s: timeout GINTSTS.RXFLVL\n",
+					 __func__);
+			} else {
+				/*
+				 * Pop GLOBAL OUT NAK status packet from RxFIFO
+				 * to assert GOUTNAKEFF interrupt
+				 */
+				dwc2_readl(hsotg, GRXSTSP);
+			}
+		}
+
+		/* Wait for global nak to take effect */
+		if (dwc2_hsotg_wait_bit_set(hsotg, GINTSTS,
+					    GINTSTS_GOUTNAKEFF, 100))
+			dev_warn(hsotg->dev, "%s: timeout GINTSTS.GOUTNAKEFF\n",
+				 __func__);
+	}
+
+	/* Disable ep */
+	dwc2_set_bit(hsotg, epctrl_reg, DXEPCTL_EPDIS | DXEPCTL_SNAK);
+
+	/* Wait for ep to be disabled */
+	if (dwc2_hsotg_wait_bit_set(hsotg, epint_reg, DXEPINT_EPDISBLD, 100))
+		dev_warn(hsotg->dev,
+			 "%s: timeout DOEPCTL.EPDisable\n", __func__);
+
+	/* Clear EPDISBLD interrupt */
+	dwc2_set_bit(hsotg, epint_reg, DXEPINT_EPDISBLD);
+
+	if (hs_ep->dir_in) {
+		unsigned short fifo_index;
+
+		if (hsotg->dedicated_fifos || hs_ep->periodic)
+			fifo_index = hs_ep->fifo_index;
+		else
+			fifo_index = 0;
+
+		/* Flush TX FIFO */
+		dwc2_flush_tx_fifo(hsotg, fifo_index);
+
+		/* Clear Global In NP NAK in Shared FIFO for non periodic ep */
+		if (!hsotg->dedicated_fifos && !hs_ep->periodic)
+			dwc2_set_bit(hsotg, DCTL, DCTL_CGNPINNAK);
+
+	} else {
+		/* Remove global NAKs */
+		dwc2_set_bit(hsotg, DCTL, DCTL_CGOUTNAK);
+	}
+}
+
+/**
+ * dwc2_hsotg_ep_enable - enable the given endpoint
+ * @ep: The USB endpint to configure
+ * @desc: The USB endpoint descriptor to configure with.
+ *
+ * This is called from the USB gadget code's usb_ep_enable().
+ */
+static int dwc2_hsotg_ep_enable(struct usb_ep *ep,
+				const struct usb_endpoint_descriptor *desc)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	unsigned long flags;
+	unsigned int index = hs_ep->index;
+	u32 epctrl_reg;
+	u32 epctrl;
+	u32 mps;
+	u32 mc;
+	u32 mask;
+	unsigned int dir_in;
+	unsigned int i, val, size;
+	int ret = 0;
+	unsigned char ep_type;
+	int desc_num;
+
+	dev_dbg(hsotg->dev,
+		"%s: ep %s: a 0x%02x, attr 0x%02x, mps 0x%04x, intr %d\n",
+		__func__, ep->name, desc->bEndpointAddress, desc->bmAttributes,
+		desc->wMaxPacketSize, desc->bInterval);
+
+	/* not to be called for EP0 */
+	if (index == 0) {
+		dev_err(hsotg->dev, "%s: called for EP 0\n", __func__);
+		return -EINVAL;
+	}
+
+	dir_in = (desc->bEndpointAddress & USB_ENDPOINT_DIR_MASK) ? 1 : 0;
+	if (dir_in != hs_ep->dir_in) {
+		dev_err(hsotg->dev, "%s: direction mismatch!\n", __func__);
+		return -EINVAL;
+	}
+
+	ep_type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+	mps = usb_endpoint_maxp(desc);
+	mc = usb_endpoint_maxp_mult(desc);
+
+	/* ISOC IN in DDMA supported bInterval up to 10 */
+	if (using_desc_dma(hsotg) && ep_type == USB_ENDPOINT_XFER_ISOC &&
+	    dir_in && desc->bInterval > 10) {
+		dev_err(hsotg->dev,
+			"%s: ISOC IN, DDMA: bInterval>10 not supported!\n", __func__);
+		return -EINVAL;
+	}
+
+	/* High bandwidth ISOC OUT in DDMA not supported */
+	if (using_desc_dma(hsotg) && ep_type == USB_ENDPOINT_XFER_ISOC &&
+	    !dir_in && mc > 1) {
+		dev_err(hsotg->dev,
+			"%s: ISOC OUT, DDMA: HB not supported!\n", __func__);
+		return -EINVAL;
+	}
+
+	/* note, we handle this here instead of dwc2_hsotg_set_ep_maxpacket */
+
+	epctrl_reg = dir_in ? DIEPCTL(index) : DOEPCTL(index);
+	epctrl = dwc2_readl(hsotg, epctrl_reg);
+
+	dev_dbg(hsotg->dev, "%s: read DxEPCTL=0x%08x from 0x%08x\n",
+		__func__, epctrl, epctrl_reg);
+
+	if (using_desc_dma(hsotg) && ep_type == USB_ENDPOINT_XFER_ISOC)
+		desc_num = MAX_DMA_DESC_NUM_HS_ISOC;
+	else
+		desc_num = MAX_DMA_DESC_NUM_GENERIC;
+
+	/* Allocate DMA descriptor chain for non-ctrl endpoints */
+	if (using_desc_dma(hsotg) && !hs_ep->desc_list) {
+		hs_ep->desc_list = dmam_alloc_coherent(hsotg->dev,
+			desc_num * sizeof(struct dwc2_dma_desc),
+			&hs_ep->desc_list_dma, GFP_ATOMIC);
+		if (!hs_ep->desc_list) {
+			ret = -ENOMEM;
+			goto error2;
+		}
+	}
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+
+	epctrl &= ~(DXEPCTL_EPTYPE_MASK | DXEPCTL_MPS_MASK);
+	epctrl |= DXEPCTL_MPS(mps);
+
+	/*
+	 * mark the endpoint as active, otherwise the core may ignore
+	 * transactions entirely for this endpoint
+	 */
+	epctrl |= DXEPCTL_USBACTEP;
+
+	/* update the endpoint state */
+	dwc2_hsotg_set_ep_maxpacket(hsotg, hs_ep->index, mps, mc, dir_in);
+
+	/* default, set to non-periodic */
+	hs_ep->isochronous = 0;
+	hs_ep->periodic = 0;
+	hs_ep->halted = 0;
+	hs_ep->wedged = 0;
+	hs_ep->interval = desc->bInterval;
+
+	switch (ep_type) {
+	case USB_ENDPOINT_XFER_ISOC:
+		epctrl |= DXEPCTL_EPTYPE_ISO;
+		epctrl |= DXEPCTL_SETEVENFR;
+		hs_ep->isochronous = 1;
+		hs_ep->interval = 1 << (desc->bInterval - 1);
+		hs_ep->target_frame = TARGET_FRAME_INITIAL;
+		hs_ep->next_desc = 0;
+		hs_ep->compl_desc = 0;
+		if (dir_in) {
+			hs_ep->periodic = 1;
+			mask = dwc2_readl(hsotg, DIEPMSK);
+			mask |= DIEPMSK_NAKMSK;
+			dwc2_writel(hsotg, mask, DIEPMSK);
+		} else {
+			epctrl |= DXEPCTL_SNAK;
+			mask = dwc2_readl(hsotg, DOEPMSK);
+			mask |= DOEPMSK_OUTTKNEPDISMSK;
+			dwc2_writel(hsotg, mask, DOEPMSK);
+		}
+		break;
+
+	case USB_ENDPOINT_XFER_BULK:
+		epctrl |= DXEPCTL_EPTYPE_BULK;
+		break;
+
+	case USB_ENDPOINT_XFER_INT:
+		if (dir_in)
+			hs_ep->periodic = 1;
+
+		if (hsotg->gadget.speed == USB_SPEED_HIGH)
+			hs_ep->interval = 1 << (desc->bInterval - 1);
+
+		epctrl |= DXEPCTL_EPTYPE_INTERRUPT;
+		break;
+
+	case USB_ENDPOINT_XFER_CONTROL:
+		epctrl |= DXEPCTL_EPTYPE_CONTROL;
+		break;
+	}
+
+	/*
+	 * if the hardware has dedicated fifos, we must give each IN EP
+	 * a unique tx-fifo even if it is non-periodic.
+	 */
+	if (dir_in && hsotg->dedicated_fifos) {
+		unsigned fifo_count = dwc2_hsotg_tx_fifo_count(hsotg);
+		u32 fifo_index = 0;
+		u32 fifo_size = UINT_MAX;
+
+		size = hs_ep->ep.maxpacket * hs_ep->mc;
+		for (i = 1; i <= fifo_count; ++i) {
+			if (hsotg->fifo_map & (1 << i))
+				continue;
+			val = dwc2_readl(hsotg, DPTXFSIZN(i));
+			val = (val >> FIFOSIZE_DEPTH_SHIFT) * 4;
+			if (val < size)
+				continue;
+			/* Search for smallest acceptable fifo */
+			if (val < fifo_size) {
+				fifo_size = val;
+				fifo_index = i;
+			}
+		}
+		if (!fifo_index) {
+			dev_err(hsotg->dev,
+				"%s: No suitable fifo found\n", __func__);
+			ret = -ENOMEM;
+			goto error1;
+		}
+		epctrl &= ~(DXEPCTL_TXFNUM_LIMIT << DXEPCTL_TXFNUM_SHIFT);
+		hsotg->fifo_map |= 1 << fifo_index;
+		epctrl |= DXEPCTL_TXFNUM(fifo_index);
+		hs_ep->fifo_index = fifo_index;
+		hs_ep->fifo_size = fifo_size;
+	}
+
+	/* for non control endpoints, set PID to D0 */
+	if (index && !hs_ep->isochronous)
+		epctrl |= DXEPCTL_SETD0PID;
+
+	/* WA for Full speed ISOC IN in DDMA mode.
+	 * By Clear NAK status of EP, core will send ZLP
+	 * to IN token and assert NAK interrupt relying
+	 * on TxFIFO status only
+	 */
+
+	if (hsotg->gadget.speed == USB_SPEED_FULL &&
+	    hs_ep->isochronous && dir_in) {
+		/* The WA applies only to core versions from 2.72a
+		 * to 4.00a (including both). Also for FS_IOT_1.00a
+		 * and HS_IOT_1.00a.
+		 */
+		u32 gsnpsid = dwc2_readl(hsotg, GSNPSID);
+
+		if ((gsnpsid >= DWC2_CORE_REV_2_72a &&
+		     gsnpsid <= DWC2_CORE_REV_4_00a) ||
+		     gsnpsid == DWC2_FS_IOT_REV_1_00a ||
+		     gsnpsid == DWC2_HS_IOT_REV_1_00a)
+			epctrl |= DXEPCTL_CNAK;
+	}
+
+	dev_dbg(hsotg->dev, "%s: write DxEPCTL=0x%08x\n",
+		__func__, epctrl);
+
+	dwc2_writel(hsotg, epctrl, epctrl_reg);
+	dev_dbg(hsotg->dev, "%s: read DxEPCTL=0x%08x\n",
+		__func__, dwc2_readl(hsotg, epctrl_reg));
+
+	/* enable the endpoint interrupt */
+	dwc2_hsotg_ctrl_epint(hsotg, index, dir_in, 1);
+
+error1:
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+
+error2:
+	if (ret && using_desc_dma(hsotg) && hs_ep->desc_list) {
+		dmam_free_coherent(hsotg->dev, desc_num *
+			sizeof(struct dwc2_dma_desc),
+			hs_ep->desc_list, hs_ep->desc_list_dma);
+		hs_ep->desc_list = NULL;
+	}
+
+	return ret;
+}
+
+/**
+ * dwc2_hsotg_ep_disable - disable given endpoint
+ * @ep: The endpoint to disable.
+ */
+static int dwc2_hsotg_ep_disable(struct usb_ep *ep)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	int dir_in = hs_ep->dir_in;
+	int index = hs_ep->index;
+	u32 epctrl_reg;
+	u32 ctrl;
+
+	dev_dbg(hsotg->dev, "%s(ep %p)\n", __func__, ep);
+
+	if (ep == &hsotg->eps_out[0]->ep) {
+		dev_err(hsotg->dev, "%s: called for ep0\n", __func__);
+		return -EINVAL;
+	}
+
+	if (hsotg->op_state != OTG_STATE_B_PERIPHERAL) {
+		dev_err(hsotg->dev, "%s: called in host mode?\n", __func__);
+		return -EINVAL;
+	}
+
+	epctrl_reg = dir_in ? DIEPCTL(index) : DOEPCTL(index);
+
+	ctrl = dwc2_readl(hsotg, epctrl_reg);
+
+	if (ctrl & DXEPCTL_EPENA)
+		dwc2_hsotg_ep_stop_xfr(hsotg, hs_ep);
+
+	ctrl &= ~DXEPCTL_EPENA;
+	ctrl &= ~DXEPCTL_USBACTEP;
+	ctrl |= DXEPCTL_SNAK;
+
+	dev_dbg(hsotg->dev, "%s: DxEPCTL=0x%08x\n", __func__, ctrl);
+	dwc2_writel(hsotg, ctrl, epctrl_reg);
+
+	/* disable endpoint interrupts */
+	dwc2_hsotg_ctrl_epint(hsotg, hs_ep->index, hs_ep->dir_in, 0);
+
+	/* terminate all requests with shutdown */
+	kill_all_requests(hsotg, hs_ep, -ESHUTDOWN);
+
+	hsotg->fifo_map &= ~(1 << hs_ep->fifo_index);
+	hs_ep->fifo_index = 0;
+	hs_ep->fifo_size = 0;
+
+	return 0;
+}
+
+static int dwc2_hsotg_ep_disable_lock(struct usb_ep *ep)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+	ret = dwc2_hsotg_ep_disable(ep);
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+	return ret;
+}
+
+/**
+ * on_list - check request is on the given endpoint
+ * @ep: The endpoint to check.
+ * @test: The request to test if it is on the endpoint.
+ */
+static bool on_list(struct dwc2_hsotg_ep *ep, struct dwc2_hsotg_req *test)
+{
+	struct dwc2_hsotg_req *req, *treq;
+
+	list_for_each_entry_safe(req, treq, &ep->queue, queue) {
+		if (req == test)
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * dwc2_hsotg_ep_dequeue - dequeue given endpoint
+ * @ep: The endpoint to dequeue.
+ * @req: The request to be removed from a queue.
+ */
+static int dwc2_hsotg_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
+{
+	struct dwc2_hsotg_req *hs_req = our_req(req);
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+	unsigned long flags;
+
+	dev_dbg(hs->dev, "ep_dequeue(%p,%p)\n", ep, req);
+
+	spin_lock_irqsave(&hs->lock, flags);
+
+	if (!on_list(hs_ep, hs_req)) {
+		spin_unlock_irqrestore(&hs->lock, flags);
+		return -EINVAL;
+	}
+
+	/* Dequeue already started request */
+	if (req == &hs_ep->req->req)
+		dwc2_hsotg_ep_stop_xfr(hs, hs_ep);
+
+	dwc2_hsotg_complete_request(hs, hs_ep, hs_req, -ECONNRESET);
+	spin_unlock_irqrestore(&hs->lock, flags);
+
+	return 0;
+}
+
+/**
+ * dwc2_gadget_ep_set_wedge - set wedge on a given endpoint
+ * @ep: The endpoint to be wedged.
+ *
+ */
+static int dwc2_gadget_ep_set_wedge(struct usb_ep *ep)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+
+	unsigned long	flags;
+	int		ret;
+
+	spin_lock_irqsave(&hs->lock, flags);
+	hs_ep->wedged = 1;
+	ret = dwc2_hsotg_ep_sethalt(ep, 1, false);
+	spin_unlock_irqrestore(&hs->lock, flags);
+
+	return ret;
+}
+
+/**
+ * dwc2_hsotg_ep_sethalt - set halt on a given endpoint
+ * @ep: The endpoint to set halt.
+ * @value: Set or unset the halt.
+ * @now: If true, stall the endpoint now. Otherwise return -EAGAIN if
+ *       the endpoint is busy processing requests.
+ *
+ * We need to stall the endpoint immediately if request comes from set_feature
+ * protocol command handler.
+ */
+static int dwc2_hsotg_ep_sethalt(struct usb_ep *ep, int value, bool now)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+	int index = hs_ep->index;
+	u32 epreg;
+	u32 epctl;
+	u32 xfertype;
+
+	dev_info(hs->dev, "%s(ep %p %s, %d)\n", __func__, ep, ep->name, value);
+
+	if (index == 0) {
+		if (value)
+			dwc2_hsotg_stall_ep0(hs);
+		else
+			dev_warn(hs->dev,
+				 "%s: can't clear halt on ep0\n", __func__);
+		return 0;
+	}
+
+	if (hs_ep->isochronous) {
+		dev_err(hs->dev, "%s is Isochronous Endpoint\n", ep->name);
+		return -EINVAL;
+	}
+
+	if (!now && value && !list_empty(&hs_ep->queue)) {
+		dev_dbg(hs->dev, "%s request is pending, cannot halt\n",
+			ep->name);
+		return -EAGAIN;
+	}
+
+	if (hs_ep->dir_in) {
+		epreg = DIEPCTL(index);
+		epctl = dwc2_readl(hs, epreg);
+
+		if (value) {
+			epctl |= DXEPCTL_STALL | DXEPCTL_SNAK;
+			if (epctl & DXEPCTL_EPENA)
+				epctl |= DXEPCTL_EPDIS;
+		} else {
+			epctl &= ~DXEPCTL_STALL;
+			hs_ep->wedged = 0;
+			xfertype = epctl & DXEPCTL_EPTYPE_MASK;
+			if (xfertype == DXEPCTL_EPTYPE_BULK ||
+			    xfertype == DXEPCTL_EPTYPE_INTERRUPT)
+				epctl |= DXEPCTL_SETD0PID;
+		}
+		dwc2_writel(hs, epctl, epreg);
+	} else {
+		epreg = DOEPCTL(index);
+		epctl = dwc2_readl(hs, epreg);
+
+		if (value) {
+			/* Unmask GOUTNAKEFF interrupt */
+			dwc2_hsotg_en_gsint(hs, GINTSTS_GOUTNAKEFF);
+
+			if (!(dwc2_readl(hs, GINTSTS) & GINTSTS_GOUTNAKEFF))
+				dwc2_set_bit(hs, DCTL, DCTL_SGOUTNAK);
+			// STALL bit will be set in GOUTNAKEFF interrupt handler
+		} else {
+			epctl &= ~DXEPCTL_STALL;
+			hs_ep->wedged = 0;
+			xfertype = epctl & DXEPCTL_EPTYPE_MASK;
+			if (xfertype == DXEPCTL_EPTYPE_BULK ||
+			    xfertype == DXEPCTL_EPTYPE_INTERRUPT)
+				epctl |= DXEPCTL_SETD0PID;
+			dwc2_writel(hs, epctl, epreg);
+		}
+	}
+
+	hs_ep->halted = value;
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_ep_sethalt_lock - set halt on a given endpoint with lock held
+ * @ep: The endpoint to set halt.
+ * @value: Set or unset the halt.
+ */
+static int dwc2_hsotg_ep_sethalt_lock(struct usb_ep *ep, int value)
+{
+	struct dwc2_hsotg_ep *hs_ep = our_ep(ep);
+	struct dwc2_hsotg *hs = hs_ep->parent;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&hs->lock, flags);
+	ret = dwc2_hsotg_ep_sethalt(ep, value, false);
+	spin_unlock_irqrestore(&hs->lock, flags);
+
+	return ret;
+}
+
+static const struct usb_ep_ops dwc2_hsotg_ep_ops = {
+	.enable		= dwc2_hsotg_ep_enable,
+	.disable	= dwc2_hsotg_ep_disable_lock,
+	.alloc_request	= dwc2_hsotg_ep_alloc_request,
+	.free_request	= dwc2_hsotg_ep_free_request,
+	.queue		= dwc2_hsotg_ep_queue_lock,
+	.dequeue	= dwc2_hsotg_ep_dequeue,
+	.set_halt	= dwc2_hsotg_ep_sethalt_lock,
+	.set_wedge	= dwc2_gadget_ep_set_wedge,
+	/* note, don't believe we have any call for the fifo routines */
+};
+
+/**
+ * dwc2_hsotg_init - initialize the usb core
+ * @hsotg: The driver state
+ */
+static void dwc2_hsotg_init(struct dwc2_hsotg *hsotg)
+{
+	/* unmask subset of endpoint interrupts */
+
+	dwc2_writel(hsotg, DIEPMSK_TIMEOUTMSK | DIEPMSK_AHBERRMSK |
+		    DIEPMSK_EPDISBLDMSK | DIEPMSK_XFERCOMPLMSK,
+		    DIEPMSK);
+
+	dwc2_writel(hsotg, DOEPMSK_SETUPMSK | DOEPMSK_AHBERRMSK |
+		    DOEPMSK_EPDISBLDMSK | DOEPMSK_XFERCOMPLMSK,
+		    DOEPMSK);
+
+	dwc2_writel(hsotg, 0, DAINTMSK);
+
+	/* Be in disconnected state until gadget is registered */
+	dwc2_set_bit(hsotg, DCTL, DCTL_SFTDISCON);
+
+	/* setup fifos */
+
+	dev_dbg(hsotg->dev, "GRXFSIZ=0x%08x, GNPTXFSIZ=0x%08x\n",
+		dwc2_readl(hsotg, GRXFSIZ),
+		dwc2_readl(hsotg, GNPTXFSIZ));
+
+	dwc2_hsotg_init_fifo(hsotg);
+
+	if (using_dma(hsotg))
+		dwc2_set_bit(hsotg, GAHBCFG, GAHBCFG_DMA_EN);
+}
+
+/**
+ * dwc2_hsotg_udc_start - prepare the udc for work
+ * @gadget: The usb gadget state
+ * @driver: The usb gadget driver
+ *
+ * Perform initialization to prepare udc device and driver
+ * to work.
+ */
+static int dwc2_hsotg_udc_start(struct usb_gadget *gadget,
+				struct usb_gadget_driver *driver)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+	unsigned long flags;
+	int ret;
+
+	if (!hsotg) {
+		pr_err("%s: called with no device\n", __func__);
+		return -ENODEV;
+	}
+
+	if (!driver) {
+		dev_err(hsotg->dev, "%s: no driver\n", __func__);
+		return -EINVAL;
+	}
+
+	if (driver->max_speed < USB_SPEED_FULL)
+		dev_err(hsotg->dev, "%s: bad speed\n", __func__);
+
+	if (!driver->setup) {
+		dev_err(hsotg->dev, "%s: missing entry points\n", __func__);
+		return -EINVAL;
+	}
+
+	WARN_ON(hsotg->driver);
+
+	hsotg->driver = driver;
+	hsotg->gadget.dev.of_node = hsotg->dev->of_node;
+	hsotg->gadget.speed = USB_SPEED_UNKNOWN;
+
+	if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) {
+		ret = dwc2_lowlevel_hw_enable(hsotg);
+		if (ret)
+			goto err;
+	}
+
+	if (!IS_ERR_OR_NULL(hsotg->uphy))
+		otg_set_peripheral(hsotg->uphy->otg, &hsotg->gadget);
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+	if (dwc2_hw_is_device(hsotg)) {
+		dwc2_hsotg_init(hsotg);
+		dwc2_hsotg_core_init_disconnected(hsotg, false);
+	}
+
+	hsotg->enabled = 0;
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+
+	gadget->sg_supported = using_desc_dma(hsotg);
+	dev_info(hsotg->dev, "bound driver %s\n", driver->driver.name);
+
+	return 0;
+
+err:
+	hsotg->driver = NULL;
+	return ret;
+}
+
+/**
+ * dwc2_hsotg_udc_stop - stop the udc
+ * @gadget: The usb gadget state
+ *
+ * Stop udc hw block and stay tunned for future transmissions
+ */
+static int dwc2_hsotg_udc_stop(struct usb_gadget *gadget)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+	unsigned long flags;
+	int ep;
+
+	if (!hsotg)
+		return -ENODEV;
+
+	/* all endpoints should be shutdown */
+	for (ep = 1; ep < hsotg->num_of_eps; ep++) {
+		if (hsotg->eps_in[ep])
+			dwc2_hsotg_ep_disable_lock(&hsotg->eps_in[ep]->ep);
+		if (hsotg->eps_out[ep])
+			dwc2_hsotg_ep_disable_lock(&hsotg->eps_out[ep]->ep);
+	}
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+
+	hsotg->driver = NULL;
+	hsotg->gadget.speed = USB_SPEED_UNKNOWN;
+	hsotg->enabled = 0;
+
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+
+	if (!IS_ERR_OR_NULL(hsotg->uphy))
+		otg_set_peripheral(hsotg->uphy->otg, NULL);
+
+	if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
+		dwc2_lowlevel_hw_disable(hsotg);
+
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_gadget_getframe - read the frame number
+ * @gadget: The usb gadget state
+ *
+ * Read the {micro} frame number
+ */
+static int dwc2_hsotg_gadget_getframe(struct usb_gadget *gadget)
+{
+	return dwc2_hsotg_read_frameno(to_hsotg(gadget));
+}
+
+/**
+ * dwc2_hsotg_set_selfpowered - set if device is self/bus powered
+ * @gadget: The usb gadget state
+ * @is_selfpowered: Whether the device is self-powered
+ *
+ * Set if the device is self or bus powered.
+ */
+static int dwc2_hsotg_set_selfpowered(struct usb_gadget *gadget,
+				      int is_selfpowered)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+	gadget->is_selfpowered = !!is_selfpowered;
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_pullup - connect/disconnect the USB PHY
+ * @gadget: The usb gadget state
+ * @is_on: Current state of the USB PHY
+ *
+ * Connect/Disconnect the USB PHY pullup
+ */
+static int dwc2_hsotg_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+	unsigned long flags;
+
+	dev_dbg(hsotg->dev, "%s: is_on: %d op_state: %d\n", __func__, is_on,
+		hsotg->op_state);
+
+	/* Don't modify pullup state while in host mode */
+	if (hsotg->op_state != OTG_STATE_B_PERIPHERAL) {
+		hsotg->enabled = is_on;
+		return 0;
+	}
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+	if (is_on) {
+		hsotg->enabled = 1;
+		dwc2_hsotg_core_init_disconnected(hsotg, false);
+		/* Enable ACG feature in device mode,if supported */
+		dwc2_enable_acg(hsotg);
+		dwc2_hsotg_core_connect(hsotg);
+	} else {
+		dwc2_hsotg_core_disconnect(hsotg);
+		dwc2_hsotg_disconnect(hsotg);
+		hsotg->enabled = 0;
+	}
+
+	hsotg->gadget.speed = USB_SPEED_UNKNOWN;
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+
+	return 0;
+}
+
+static int dwc2_hsotg_vbus_session(struct usb_gadget *gadget, int is_active)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+	unsigned long flags;
+
+	dev_dbg(hsotg->dev, "%s: is_active: %d\n", __func__, is_active);
+	spin_lock_irqsave(&hsotg->lock, flags);
+
+	/*
+	 * If controller is in partial power down state, it must exit from
+	 * that state before being initialized / de-initialized
+	 */
+	if (hsotg->lx_state == DWC2_L2 && hsotg->in_ppd)
+		/*
+		 * No need to check the return value as
+		 * registers are not being restored.
+		 */
+		dwc2_exit_partial_power_down(hsotg, 0, false);
+
+	if (is_active) {
+		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
+
+		dwc2_hsotg_core_init_disconnected(hsotg, false);
+		if (hsotg->enabled) {
+			/* Enable ACG feature in device mode,if supported */
+			dwc2_enable_acg(hsotg);
+			dwc2_hsotg_core_connect(hsotg);
+		}
+	} else {
+		dwc2_hsotg_core_disconnect(hsotg);
+		dwc2_hsotg_disconnect(hsotg);
+	}
+
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_vbus_draw - report bMaxPower field
+ * @gadget: The usb gadget state
+ * @mA: Amount of current
+ *
+ * Report how much power the device may consume to the phy.
+ */
+static int dwc2_hsotg_vbus_draw(struct usb_gadget *gadget, unsigned int mA)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(gadget);
+
+	if (IS_ERR_OR_NULL(hsotg->uphy))
+		return -ENOTSUPP;
+	return usb_phy_set_power(hsotg->uphy, mA);
+}
+
+static void dwc2_gadget_set_speed(struct usb_gadget *g, enum usb_device_speed speed)
+{
+	struct dwc2_hsotg *hsotg = to_hsotg(g);
+	unsigned long		flags;
+
+	spin_lock_irqsave(&hsotg->lock, flags);
+	switch (speed) {
+	case USB_SPEED_HIGH:
+		hsotg->params.speed = DWC2_SPEED_PARAM_HIGH;
+		break;
+	case USB_SPEED_FULL:
+		hsotg->params.speed = DWC2_SPEED_PARAM_FULL;
+		break;
+	case USB_SPEED_LOW:
+		hsotg->params.speed = DWC2_SPEED_PARAM_LOW;
+		break;
+	default:
+		dev_err(hsotg->dev, "invalid speed (%d)\n", speed);
+	}
+	spin_unlock_irqrestore(&hsotg->lock, flags);
+}
+
+static const struct usb_gadget_ops dwc2_hsotg_gadget_ops = {
+	.get_frame	= dwc2_hsotg_gadget_getframe,
+	.set_selfpowered	= dwc2_hsotg_set_selfpowered,
+	.udc_start		= dwc2_hsotg_udc_start,
+	.udc_stop		= dwc2_hsotg_udc_stop,
+	.pullup                 = dwc2_hsotg_pullup,
+	.udc_set_speed		= dwc2_gadget_set_speed,
+	.vbus_session		= dwc2_hsotg_vbus_session,
+	.vbus_draw		= dwc2_hsotg_vbus_draw,
+};
+
+/**
+ * dwc2_hsotg_initep - initialise a single endpoint
+ * @hsotg: The device state.
+ * @hs_ep: The endpoint to be initialised.
+ * @epnum: The endpoint number
+ * @dir_in: True if direction is in.
+ *
+ * Initialise the given endpoint (as part of the probe and device state
+ * creation) to give to the gadget driver. Setup the endpoint name, any
+ * direction information and other state that may be required.
+ */
+static void dwc2_hsotg_initep(struct dwc2_hsotg *hsotg,
+			      struct dwc2_hsotg_ep *hs_ep,
+				       int epnum,
+				       bool dir_in)
+{
+	char *dir;
+
+	if (epnum == 0)
+		dir = "";
+	else if (dir_in)
+		dir = "in";
+	else
+		dir = "out";
+
+	hs_ep->dir_in = dir_in;
+	hs_ep->index = epnum;
+
+	snprintf(hs_ep->name, sizeof(hs_ep->name), "ep%d%s", epnum, dir);
+
+	INIT_LIST_HEAD(&hs_ep->queue);
+	INIT_LIST_HEAD(&hs_ep->ep.ep_list);
+
+	/* add to the list of endpoints known by the gadget driver */
+	if (epnum)
+		list_add_tail(&hs_ep->ep.ep_list, &hsotg->gadget.ep_list);
+
+	hs_ep->parent = hsotg;
+	hs_ep->ep.name = hs_ep->name;
+
+	if (hsotg->params.speed == DWC2_SPEED_PARAM_LOW)
+		usb_ep_set_maxpacket_limit(&hs_ep->ep, 8);
+	else
+		usb_ep_set_maxpacket_limit(&hs_ep->ep,
+					   epnum ? 1024 : EP0_MPS_LIMIT);
+	hs_ep->ep.ops = &dwc2_hsotg_ep_ops;
+
+	if (epnum == 0) {
+		hs_ep->ep.caps.type_control = true;
+	} else {
+		if (hsotg->params.speed != DWC2_SPEED_PARAM_LOW) {
+			hs_ep->ep.caps.type_iso = true;
+			hs_ep->ep.caps.type_bulk = true;
+		}
+		hs_ep->ep.caps.type_int = true;
+	}
+
+	if (dir_in)
+		hs_ep->ep.caps.dir_in = true;
+	else
+		hs_ep->ep.caps.dir_out = true;
+
+	/*
+	 * if we're using dma, we need to set the next-endpoint pointer
+	 * to be something valid.
+	 */
+
+	if (using_dma(hsotg)) {
+		u32 next = DXEPCTL_NEXTEP((epnum + 1) % 15);
+
+		if (dir_in)
+			dwc2_writel(hsotg, next, DIEPCTL(epnum));
+		else
+			dwc2_writel(hsotg, next, DOEPCTL(epnum));
+	}
+}
+
+/**
+ * dwc2_hsotg_hw_cfg - read HW configuration registers
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ * Read the USB core HW configuration registers
+ */
+static int dwc2_hsotg_hw_cfg(struct dwc2_hsotg *hsotg)
+{
+	u32 cfg;
+	u32 ep_type;
+	u32 i;
+
+	/* check hardware configuration */
+
+	hsotg->num_of_eps = hsotg->hw_params.num_dev_ep;
+
+	/* Add ep0 */
+	hsotg->num_of_eps++;
+
+	hsotg->eps_in[0] = devm_kzalloc(hsotg->dev,
+					sizeof(struct dwc2_hsotg_ep),
+					GFP_KERNEL);
+	if (!hsotg->eps_in[0])
+		return -ENOMEM;
+	/* Same dwc2_hsotg_ep is used in both directions for ep0 */
+	hsotg->eps_out[0] = hsotg->eps_in[0];
+
+	cfg = hsotg->hw_params.dev_ep_dirs;
+	for (i = 1, cfg >>= 2; i < hsotg->num_of_eps; i++, cfg >>= 2) {
+		ep_type = cfg & 3;
+		/* Direction in or both */
+		if (!(ep_type & 2)) {
+			hsotg->eps_in[i] = devm_kzalloc(hsotg->dev,
+				sizeof(struct dwc2_hsotg_ep), GFP_KERNEL);
+			if (!hsotg->eps_in[i])
+				return -ENOMEM;
+		}
+		/* Direction out or both */
+		if (!(ep_type & 1)) {
+			hsotg->eps_out[i] = devm_kzalloc(hsotg->dev,
+				sizeof(struct dwc2_hsotg_ep), GFP_KERNEL);
+			if (!hsotg->eps_out[i])
+				return -ENOMEM;
+		}
+	}
+
+	hsotg->fifo_mem = hsotg->hw_params.total_fifo_size;
+	hsotg->dedicated_fifos = hsotg->hw_params.en_multiple_tx_fifo;
+
+	dev_info(hsotg->dev, "EPs: %d, %s fifos, %d entries in SPRAM\n",
+		 hsotg->num_of_eps,
+		 hsotg->dedicated_fifos ? "dedicated" : "shared",
+		 hsotg->fifo_mem);
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_dump - dump state of the udc
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ */
+static void dwc2_hsotg_dump(struct dwc2_hsotg *hsotg)
+{
+#ifdef DEBUG
+	struct device *dev = hsotg->dev;
+	u32 val;
+	int idx;
+
+	dev_info(dev, "DCFG=0x%08x, DCTL=0x%08x, DIEPMSK=%08x\n",
+		 dwc2_readl(hsotg, DCFG), dwc2_readl(hsotg, DCTL),
+		 dwc2_readl(hsotg, DIEPMSK));
+
+	dev_info(dev, "GAHBCFG=0x%08x, GHWCFG1=0x%08x\n",
+		 dwc2_readl(hsotg, GAHBCFG), dwc2_readl(hsotg, GHWCFG1));
+
+	dev_info(dev, "GRXFSIZ=0x%08x, GNPTXFSIZ=0x%08x\n",
+		 dwc2_readl(hsotg, GRXFSIZ), dwc2_readl(hsotg, GNPTXFSIZ));
+
+	/* show periodic fifo settings */
+
+	for (idx = 1; idx < hsotg->num_of_eps; idx++) {
+		val = dwc2_readl(hsotg, DPTXFSIZN(idx));
+		dev_info(dev, "DPTx[%d] FSize=%d, StAddr=0x%08x\n", idx,
+			 val >> FIFOSIZE_DEPTH_SHIFT,
+			 val & FIFOSIZE_STARTADDR_MASK);
+	}
+
+	for (idx = 0; idx < hsotg->num_of_eps; idx++) {
+		dev_info(dev,
+			 "ep%d-in: EPCTL=0x%08x, SIZ=0x%08x, DMA=0x%08x\n", idx,
+			 dwc2_readl(hsotg, DIEPCTL(idx)),
+			 dwc2_readl(hsotg, DIEPTSIZ(idx)),
+			 dwc2_readl(hsotg, DIEPDMA(idx)));
+
+		val = dwc2_readl(hsotg, DOEPCTL(idx));
+		dev_info(dev,
+			 "ep%d-out: EPCTL=0x%08x, SIZ=0x%08x, DMA=0x%08x\n",
+			 idx, dwc2_readl(hsotg, DOEPCTL(idx)),
+			 dwc2_readl(hsotg, DOEPTSIZ(idx)),
+			 dwc2_readl(hsotg, DOEPDMA(idx)));
+	}
+
+	dev_info(dev, "DVBUSDIS=0x%08x, DVBUSPULSE=%08x\n",
+		 dwc2_readl(hsotg, DVBUSDIS), dwc2_readl(hsotg, DVBUSPULSE));
+#endif
+}
+
+/**
+ * dwc2_gadget_init - init function for gadget
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ */
+int dwc2_gadget_init(struct dwc2_hsotg *hsotg)
+{
+	struct device *dev = hsotg->dev;
+	int epnum;
+	int ret;
+
+	/* Dump fifo information */
+	dev_dbg(dev, "NonPeriodic TXFIFO size: %d\n",
+		hsotg->params.g_np_tx_fifo_size);
+	dev_dbg(dev, "RXFIFO size: %d\n", hsotg->params.g_rx_fifo_size);
+
+	switch (hsotg->params.speed) {
+	case DWC2_SPEED_PARAM_LOW:
+		hsotg->gadget.max_speed = USB_SPEED_LOW;
+		break;
+	case DWC2_SPEED_PARAM_FULL:
+		hsotg->gadget.max_speed = USB_SPEED_FULL;
+		break;
+	default:
+		hsotg->gadget.max_speed = USB_SPEED_HIGH;
+		break;
+	}
+
+	hsotg->gadget.ops = &dwc2_hsotg_gadget_ops;
+	hsotg->gadget.name = dev_name(dev);
+	hsotg->gadget.otg_caps = &hsotg->params.otg_caps;
+	hsotg->remote_wakeup_allowed = 0;
+
+	if (hsotg->params.lpm)
+		hsotg->gadget.lpm_capable = true;
+
+	if (hsotg->dr_mode == USB_DR_MODE_OTG)
+		hsotg->gadget.is_otg = 1;
+	else if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
+		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
+
+	ret = dwc2_hsotg_hw_cfg(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "Hardware configuration failed: %d\n", ret);
+		return ret;
+	}
+
+	hsotg->ctrl_buff = devm_kzalloc(hsotg->dev,
+			DWC2_CTRL_BUFF_SIZE, GFP_KERNEL);
+	if (!hsotg->ctrl_buff)
+		return -ENOMEM;
+
+	hsotg->ep0_buff = devm_kzalloc(hsotg->dev,
+			DWC2_CTRL_BUFF_SIZE, GFP_KERNEL);
+	if (!hsotg->ep0_buff)
+		return -ENOMEM;
+
+	if (using_desc_dma(hsotg)) {
+		ret = dwc2_gadget_alloc_ctrl_desc_chains(hsotg);
+		if (ret < 0)
+			return ret;
+	}
+
+	ret = devm_request_irq(hsotg->dev, hsotg->irq, dwc2_hsotg_irq,
+			       IRQF_SHARED, dev_name(hsotg->dev), hsotg);
+	if (ret < 0) {
+		dev_err(dev, "cannot claim IRQ for gadget\n");
+		return ret;
+	}
+
+	/* hsotg->num_of_eps holds number of EPs other than ep0 */
+
+	if (hsotg->num_of_eps == 0) {
+		dev_err(dev, "wrong number of EPs (zero)\n");
+		return -EINVAL;
+	}
+
+	/* setup endpoint information */
+
+	INIT_LIST_HEAD(&hsotg->gadget.ep_list);
+	hsotg->gadget.ep0 = &hsotg->eps_out[0]->ep;
+
+	/* allocate EP0 request */
+
+	hsotg->ctrl_req = dwc2_hsotg_ep_alloc_request(&hsotg->eps_out[0]->ep,
+						     GFP_KERNEL);
+	if (!hsotg->ctrl_req) {
+		dev_err(dev, "failed to allocate ctrl req\n");
+		return -ENOMEM;
+	}
+
+	/* initialise the endpoints now the core has been initialised */
+	for (epnum = 0; epnum < hsotg->num_of_eps; epnum++) {
+		if (hsotg->eps_in[epnum])
+			dwc2_hsotg_initep(hsotg, hsotg->eps_in[epnum],
+					  epnum, 1);
+		if (hsotg->eps_out[epnum])
+			dwc2_hsotg_initep(hsotg, hsotg->eps_out[epnum],
+					  epnum, 0);
+	}
+
+	dwc2_hsotg_dump(hsotg);
+
+	return 0;
+}
+
+/**
+ * dwc2_hsotg_remove - remove function for hsotg driver
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ */
+int dwc2_hsotg_remove(struct dwc2_hsotg *hsotg)
+{
+	usb_del_gadget_udc(&hsotg->gadget);
+	dwc2_hsotg_ep_free_request(&hsotg->eps_out[0]->ep, hsotg->ctrl_req);
+
+	return 0;
+}
+
+int dwc2_hsotg_suspend(struct dwc2_hsotg *hsotg)
+{
+	unsigned long flags;
+
+	if (hsotg->lx_state != DWC2_L0)
+		return 0;
+
+	if (hsotg->driver) {
+		int ep;
+
+		dev_info(hsotg->dev, "suspending usb gadget %s\n",
+			 hsotg->driver->driver.name);
+
+		spin_lock_irqsave(&hsotg->lock, flags);
+		if (hsotg->enabled)
+			dwc2_hsotg_core_disconnect(hsotg);
+		dwc2_hsotg_disconnect(hsotg);
+		hsotg->gadget.speed = USB_SPEED_UNKNOWN;
+		spin_unlock_irqrestore(&hsotg->lock, flags);
+
+		for (ep = 1; ep < hsotg->num_of_eps; ep++) {
+			if (hsotg->eps_in[ep])
+				dwc2_hsotg_ep_disable_lock(&hsotg->eps_in[ep]->ep);
+			if (hsotg->eps_out[ep])
+				dwc2_hsotg_ep_disable_lock(&hsotg->eps_out[ep]->ep);
+		}
+	}
+
+	return 0;
+}
+
+int dwc2_hsotg_resume(struct dwc2_hsotg *hsotg)
+{
+	unsigned long flags;
+
+	if (hsotg->lx_state == DWC2_L2)
+		return 0;
+
+	if (hsotg->driver) {
+		dev_info(hsotg->dev, "resuming usb gadget %s\n",
+			 hsotg->driver->driver.name);
+
+		spin_lock_irqsave(&hsotg->lock, flags);
+		dwc2_hsotg_core_init_disconnected(hsotg, false);
+		if (hsotg->enabled) {
+			/* Enable ACG feature in device mode,if supported */
+			dwc2_enable_acg(hsotg);
+			dwc2_hsotg_core_connect(hsotg);
+		}
+		spin_unlock_irqrestore(&hsotg->lock, flags);
+	}
+
+	return 0;
+}
+
+/**
+ * dwc2_backup_device_registers() - Backup controller device registers.
+ * When suspending usb bus, registers needs to be backuped
+ * if controller power is disabled once suspended.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ */
+int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg)
+{
+	struct dwc2_dregs_backup *dr;
+	int i;
+
+	dev_dbg(hsotg->dev, "%s\n", __func__);
+
+	/* Backup dev regs */
+	dr = &hsotg->dr_backup;
+
+	dr->dcfg = dwc2_readl(hsotg, DCFG);
+	dr->dctl = dwc2_readl(hsotg, DCTL);
+	dr->daintmsk = dwc2_readl(hsotg, DAINTMSK);
+	dr->diepmsk = dwc2_readl(hsotg, DIEPMSK);
+	dr->doepmsk = dwc2_readl(hsotg, DOEPMSK);
+
+	for (i = 0; i < hsotg->num_of_eps; i++) {
+		/* Backup IN EPs */
+		dr->diepctl[i] = dwc2_readl(hsotg, DIEPCTL(i));
+
+		/* Ensure DATA PID is correctly configured */
+		if (dr->diepctl[i] & DXEPCTL_DPID)
+			dr->diepctl[i] |= DXEPCTL_SETD1PID;
+		else
+			dr->diepctl[i] |= DXEPCTL_SETD0PID;
+
+		dr->dieptsiz[i] = dwc2_readl(hsotg, DIEPTSIZ(i));
+		dr->diepdma[i] = dwc2_readl(hsotg, DIEPDMA(i));
+
+		/* Backup OUT EPs */
+		dr->doepctl[i] = dwc2_readl(hsotg, DOEPCTL(i));
+
+		/* Ensure DATA PID is correctly configured */
+		if (dr->doepctl[i] & DXEPCTL_DPID)
+			dr->doepctl[i] |= DXEPCTL_SETD1PID;
+		else
+			dr->doepctl[i] |= DXEPCTL_SETD0PID;
+
+		dr->doeptsiz[i] = dwc2_readl(hsotg, DOEPTSIZ(i));
+		dr->doepdma[i] = dwc2_readl(hsotg, DOEPDMA(i));
+		dr->dtxfsiz[i] = dwc2_readl(hsotg, DPTXFSIZN(i));
+	}
+	dr->valid = true;
+	return 0;
+}
+
+/**
+ * dwc2_restore_device_registers() - Restore controller device registers.
+ * When resuming usb bus, device registers needs to be restored
+ * if controller power were disabled.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @remote_wakeup: Indicates whether resume is initiated by Device or Host.
+ *
+ * Return: 0 if successful, negative error code otherwise
+ */
+int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg, int remote_wakeup)
+{
+	struct dwc2_dregs_backup *dr;
+	int i;
+
+	dev_dbg(hsotg->dev, "%s\n", __func__);
+
+	/* Restore dev regs */
+	dr = &hsotg->dr_backup;
+	if (!dr->valid) {
+		dev_err(hsotg->dev, "%s: no device registers to restore\n",
+			__func__);
+		return -EINVAL;
+	}
+	dr->valid = false;
+
+	if (!remote_wakeup)
+		dwc2_writel(hsotg, dr->dctl, DCTL);
+
+	dwc2_writel(hsotg, dr->daintmsk, DAINTMSK);
+	dwc2_writel(hsotg, dr->diepmsk, DIEPMSK);
+	dwc2_writel(hsotg, dr->doepmsk, DOEPMSK);
+
+	for (i = 0; i < hsotg->num_of_eps; i++) {
+		/* Restore IN EPs */
+		dwc2_writel(hsotg, dr->dieptsiz[i], DIEPTSIZ(i));
+		dwc2_writel(hsotg, dr->diepdma[i], DIEPDMA(i));
+		dwc2_writel(hsotg, dr->doeptsiz[i], DOEPTSIZ(i));
+		/** WA for enabled EPx's IN in DDMA mode. On entering to
+		 * hibernation wrong value read and saved from DIEPDMAx,
+		 * as result BNA interrupt asserted on hibernation exit
+		 * by restoring from saved area.
+		 */
+		if (using_desc_dma(hsotg) &&
+		    (dr->diepctl[i] & DXEPCTL_EPENA))
+			dr->diepdma[i] = hsotg->eps_in[i]->desc_list_dma;
+		dwc2_writel(hsotg, dr->dtxfsiz[i], DPTXFSIZN(i));
+		dwc2_writel(hsotg, dr->diepctl[i], DIEPCTL(i));
+		/* Restore OUT EPs */
+		dwc2_writel(hsotg, dr->doeptsiz[i], DOEPTSIZ(i));
+		/* WA for enabled EPx's OUT in DDMA mode. On entering to
+		 * hibernation wrong value read and saved from DOEPDMAx,
+		 * as result BNA interrupt asserted on hibernation exit
+		 * by restoring from saved area.
+		 */
+		if (using_desc_dma(hsotg) &&
+		    (dr->doepctl[i] & DXEPCTL_EPENA))
+			dr->doepdma[i] = hsotg->eps_out[i]->desc_list_dma;
+		dwc2_writel(hsotg, dr->doepdma[i], DOEPDMA(i));
+		dwc2_writel(hsotg, dr->doepctl[i], DOEPCTL(i));
+	}
+
+	return 0;
+}
+
+/**
+ * dwc2_gadget_init_lpm - Configure the core to support LPM in device mode
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ *
+ */
+void dwc2_gadget_init_lpm(struct dwc2_hsotg *hsotg)
+{
+	u32 val;
+
+	if (!hsotg->params.lpm)
+		return;
+
+	val = GLPMCFG_LPMCAP | GLPMCFG_APPL1RES;
+	val |= hsotg->params.hird_threshold_en ? GLPMCFG_HIRD_THRES_EN : 0;
+	val |= hsotg->params.lpm_clock_gating ? GLPMCFG_ENBLSLPM : 0;
+	val |= hsotg->params.hird_threshold << GLPMCFG_HIRD_THRES_SHIFT;
+	val |= hsotg->params.besl ? GLPMCFG_ENBESL : 0;
+	val |= GLPMCFG_LPM_REJECT_CTRL_CONTROL;
+	val |= GLPMCFG_LPM_ACCEPT_CTRL_ISOC;
+	dwc2_writel(hsotg, val, GLPMCFG);
+	dev_dbg(hsotg->dev, "GLPMCFG=0x%08x\n", dwc2_readl(hsotg, GLPMCFG));
+
+	/* Unmask WKUP_ALERT Interrupt */
+	if (hsotg->params.service_interval)
+		dwc2_set_bit(hsotg, GINTMSK2, GINTMSK2_WKUP_ALERT_INT_MSK);
+}
+
+/**
+ * dwc2_gadget_program_ref_clk - Program GREFCLK register in device mode
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ *
+ */
+void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg)
+{
+	u32 val = 0;
+
+	val |= GREFCLK_REF_CLK_MODE;
+	val |= hsotg->params.ref_clk_per << GREFCLK_REFCLKPER_SHIFT;
+	val |= hsotg->params.sof_cnt_wkup_alert <<
+	       GREFCLK_SOF_CNT_WKUP_ALERT_SHIFT;
+
+	dwc2_writel(hsotg, val, GREFCLK);
+	dev_dbg(hsotg->dev, "GREFCLK=0x%08x\n", dwc2_readl(hsotg, GREFCLK));
+}
+
+/**
+ * dwc2_gadget_enter_hibernation() - Put controller in Hibernation.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ * Return non-zero if failed to enter to hibernation.
+ */
+int dwc2_gadget_enter_hibernation(struct dwc2_hsotg *hsotg)
+{
+	u32 gpwrdn;
+	int ret = 0;
+
+	/* Change to L2(suspend) state */
+	hsotg->lx_state = DWC2_L2;
+	dev_dbg(hsotg->dev, "Start of hibernation completed\n");
+	ret = dwc2_backup_global_registers(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
+			__func__);
+		return ret;
+	}
+	ret = dwc2_backup_device_registers(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to backup device registers\n",
+			__func__);
+		return ret;
+	}
+
+	gpwrdn = GPWRDN_PWRDNRSTN;
+	gpwrdn |= GPWRDN_PMUACTV;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	/* Set flag to indicate that we are in hibernation */
+	hsotg->hibernated = 1;
+
+	/* Enable interrupts from wake up logic */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn |= GPWRDN_PMUINTSEL;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	/* Unmask device mode interrupts in GPWRDN */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn |= GPWRDN_RST_DET_MSK;
+	gpwrdn |= GPWRDN_LNSTSCHG_MSK;
+	gpwrdn |= GPWRDN_STS_CHGINT_MSK;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	/* Enable Power Down Clamp */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn |= GPWRDN_PWRDNCLMP;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	/* Switch off VDD */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn |= GPWRDN_PWRDNSWTCH;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	/* Save gpwrdn register for further usage if stschng interrupt */
+	hsotg->gr_backup.gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	dev_dbg(hsotg->dev, "Hibernation completed\n");
+
+	return ret;
+}
+
+/**
+ * dwc2_gadget_exit_hibernation()
+ * This function is for exiting from Device mode hibernation by host initiated
+ * resume/reset and device initiated remote-wakeup.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @rem_wakeup: indicates whether resume is initiated by Device or Host.
+ * @reset: indicates whether resume is initiated by Reset.
+ *
+ * Return non-zero if failed to exit from hibernation.
+ */
+int dwc2_gadget_exit_hibernation(struct dwc2_hsotg *hsotg,
+				 int rem_wakeup, int reset)
+{
+	u32 pcgcctl;
+	u32 gpwrdn;
+	u32 dctl;
+	int ret = 0;
+	struct dwc2_gregs_backup *gr;
+	struct dwc2_dregs_backup *dr;
+
+	gr = &hsotg->gr_backup;
+	dr = &hsotg->dr_backup;
+
+	if (!hsotg->hibernated) {
+		dev_dbg(hsotg->dev, "Already exited from Hibernation\n");
+		return 1;
+	}
+	dev_dbg(hsotg->dev,
+		"%s: called with rem_wakeup = %d reset = %d\n",
+		__func__, rem_wakeup, reset);
+
+	dwc2_hib_restore_common(hsotg, rem_wakeup, 0);
+
+	if (!reset) {
+		/* Clear all pending interupts */
+		dwc2_writel(hsotg, 0xffffffff, GINTSTS);
+	}
+
+	/* De-assert Restore */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn &= ~GPWRDN_RESTORE;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+	udelay(10);
+
+	if (!rem_wakeup) {
+		pcgcctl = dwc2_readl(hsotg, PCGCTL);
+		pcgcctl &= ~PCGCTL_RSTPDWNMODULE;
+		dwc2_writel(hsotg, pcgcctl, PCGCTL);
+	}
+
+	/* Restore GUSBCFG, DCFG and DCTL */
+	dwc2_writel(hsotg, gr->gusbcfg, GUSBCFG);
+	dwc2_writel(hsotg, dr->dcfg, DCFG);
+	dwc2_writel(hsotg, dr->dctl, DCTL);
+
+	/* On USB Reset, reset device address to zero */
+	if (reset)
+		dwc2_clear_bit(hsotg, DCFG, DCFG_DEVADDR_MASK);
+
+	/* De-assert Wakeup Logic */
+	gpwrdn = dwc2_readl(hsotg, GPWRDN);
+	gpwrdn &= ~GPWRDN_PMUACTV;
+	dwc2_writel(hsotg, gpwrdn, GPWRDN);
+
+	if (rem_wakeup) {
+		udelay(10);
+		/* Start Remote Wakeup Signaling */
+		dwc2_writel(hsotg, dr->dctl | DCTL_RMTWKUPSIG, DCTL);
+	} else {
+		udelay(50);
+		/* Set Device programming done bit */
+		dctl = dwc2_readl(hsotg, DCTL);
+		dctl |= DCTL_PWRONPRGDONE;
+		dwc2_writel(hsotg, dctl, DCTL);
+	}
+	/* Wait for interrupts which must be cleared */
+	mdelay(2);
+	/* Clear all pending interupts */
+	dwc2_writel(hsotg, 0xffffffff, GINTSTS);
+
+	/* Restore global registers */
+	ret = dwc2_restore_global_registers(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to restore registers\n",
+			__func__);
+		return ret;
+	}
+
+	/* Restore device registers */
+	ret = dwc2_restore_device_registers(hsotg, rem_wakeup);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to restore device registers\n",
+			__func__);
+		return ret;
+	}
+
+	if (rem_wakeup) {
+		mdelay(10);
+		dctl = dwc2_readl(hsotg, DCTL);
+		dctl &= ~DCTL_RMTWKUPSIG;
+		dwc2_writel(hsotg, dctl, DCTL);
+	}
+
+	hsotg->hibernated = 0;
+	hsotg->lx_state = DWC2_L0;
+	dev_dbg(hsotg->dev, "Hibernation recovery completes here\n");
+
+	return ret;
+}
+
+/**
+ * dwc2_gadget_enter_partial_power_down() - Put controller in partial
+ * power down.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ * Return: non-zero if failed to enter device partial power down.
+ *
+ * This function is for entering device mode partial power down.
+ */
+int dwc2_gadget_enter_partial_power_down(struct dwc2_hsotg *hsotg)
+{
+	u32 pcgcctl;
+	int ret = 0;
+
+	dev_dbg(hsotg->dev, "Entering device partial power down started.\n");
+
+	/* Backup all registers */
+	ret = dwc2_backup_global_registers(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
+			__func__);
+		return ret;
+	}
+
+	ret = dwc2_backup_device_registers(hsotg);
+	if (ret) {
+		dev_err(hsotg->dev, "%s: failed to backup device registers\n",
+			__func__);
+		return ret;
+	}
+
+	/*
+	 * Clear any pending interrupts since dwc2 will not be able to
+	 * clear them after entering partial_power_down.
+	 */
+	dwc2_writel(hsotg, 0xffffffff, GINTSTS);
+
+	/* Put the controller in low power state */
+	pcgcctl = dwc2_readl(hsotg, PCGCTL);
+
+	pcgcctl |= PCGCTL_PWRCLMP;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+	udelay(5);
+
+	pcgcctl |= PCGCTL_RSTPDWNMODULE;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+	udelay(5);
+
+	pcgcctl |= PCGCTL_STOPPCLK;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+
+	/* Set in_ppd flag to 1 as here core enters suspend. */
+	hsotg->in_ppd = 1;
+	hsotg->lx_state = DWC2_L2;
+
+	dev_dbg(hsotg->dev, "Entering device partial power down completed.\n");
+
+	return ret;
+}
+
+/*
+ * dwc2_gadget_exit_partial_power_down() - Exit controller from device partial
+ * power down.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @restore: indicates whether need to restore the registers or not.
+ *
+ * Return: non-zero if failed to exit device partial power down.
+ *
+ * This function is for exiting from device mode partial power down.
+ */
+int dwc2_gadget_exit_partial_power_down(struct dwc2_hsotg *hsotg,
+					bool restore)
+{
+	u32 pcgcctl;
+	u32 dctl;
+	struct dwc2_dregs_backup *dr;
+	int ret = 0;
+
+	dr = &hsotg->dr_backup;
+
+	dev_dbg(hsotg->dev, "Exiting device partial Power Down started.\n");
+
+	pcgcctl = dwc2_readl(hsotg, PCGCTL);
+	pcgcctl &= ~PCGCTL_STOPPCLK;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+
+	pcgcctl = dwc2_readl(hsotg, PCGCTL);
+	pcgcctl &= ~PCGCTL_PWRCLMP;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+
+	pcgcctl = dwc2_readl(hsotg, PCGCTL);
+	pcgcctl &= ~PCGCTL_RSTPDWNMODULE;
+	dwc2_writel(hsotg, pcgcctl, PCGCTL);
+
+	udelay(100);
+	if (restore) {
+		ret = dwc2_restore_global_registers(hsotg);
+		if (ret) {
+			dev_err(hsotg->dev, "%s: failed to restore registers\n",
+				__func__);
+			return ret;
+		}
+		/* Restore DCFG */
+		dwc2_writel(hsotg, dr->dcfg, DCFG);
+
+		ret = dwc2_restore_device_registers(hsotg, 0);
+		if (ret) {
+			dev_err(hsotg->dev, "%s: failed to restore device registers\n",
+				__func__);
+			return ret;
+		}
+	}
+
+	/* Set the Power-On Programming done bit */
+	dctl = dwc2_readl(hsotg, DCTL);
+	dctl |= DCTL_PWRONPRGDONE;
+	dwc2_writel(hsotg, dctl, DCTL);
+
+	/* Set in_ppd flag to 0 as here core exits from suspend. */
+	hsotg->in_ppd = 0;
+	hsotg->lx_state = DWC2_L0;
+
+	dev_dbg(hsotg->dev, "Exiting device partial Power Down completed.\n");
+	return ret;
+}
+
+/**
+ * dwc2_gadget_enter_clock_gating() - Put controller in clock gating.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ *
+ * Return: non-zero if failed to enter device partial power down.
+ *
+ * This function is for entering device mode clock gating.
+ */
+void dwc2_gadget_enter_clock_gating(struct dwc2_hsotg *hsotg)
+{
+	u32 pcgctl;
+
+	dev_dbg(hsotg->dev, "Entering device clock gating.\n");
+
+	/* Set the Phy Clock bit as suspend is received. */
+	pcgctl = dwc2_readl(hsotg, PCGCTL);
+	pcgctl |= PCGCTL_STOPPCLK;
+	dwc2_writel(hsotg, pcgctl, PCGCTL);
+	udelay(5);
+
+	/* Set the Gate hclk as suspend is received. */
+	pcgctl = dwc2_readl(hsotg, PCGCTL);
+	pcgctl |= PCGCTL_GATEHCLK;
+	dwc2_writel(hsotg, pcgctl, PCGCTL);
+	udelay(5);
+
+	hsotg->lx_state = DWC2_L2;
+	hsotg->bus_suspended = true;
+}
+
+/*
+ * dwc2_gadget_exit_clock_gating() - Exit controller from device clock gating.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @rem_wakeup: indicates whether remote wake up is enabled.
+ *
+ * This function is for exiting from device mode clock gating.
+ */
+void dwc2_gadget_exit_clock_gating(struct dwc2_hsotg *hsotg, int rem_wakeup)
+{
+	u32 pcgctl;
+	u32 dctl;
+
+	dev_dbg(hsotg->dev, "Exiting device clock gating.\n");
+
+	/* Clear the Gate hclk. */
+	pcgctl = dwc2_readl(hsotg, PCGCTL);
+	pcgctl &= ~PCGCTL_GATEHCLK;
+	dwc2_writel(hsotg, pcgctl, PCGCTL);
+	udelay(5);
+
+	/* Phy Clock bit. */
+	pcgctl = dwc2_readl(hsotg, PCGCTL);
+	pcgctl &= ~PCGCTL_STOPPCLK;
+	dwc2_writel(hsotg, pcgctl, PCGCTL);
+	udelay(5);
+
+	if (rem_wakeup) {
+		/* Set Remote Wakeup Signaling */
+		dctl = dwc2_readl(hsotg, DCTL);
+		dctl |= DCTL_RMTWKUPSIG;
+		dwc2_writel(hsotg, dctl, DCTL);
+	}
+
+	/* Change to L0 state */
+	call_gadget(hsotg, resume);
+	hsotg->lx_state = DWC2_L0;
+	hsotg->bus_suspended = false;
+}