Adding upstream version 5.10.209.upstream/5.10.209upstream

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

1 files changed, 3401 insertions, 0 deletions

diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
new file mode 100644
index 000000000..210c1d615
--- /dev/null
+++ b/drivers/usb/cdns3/gadget.c
@@ -0,0 +1,3401 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - gadget side.
+ *
+ * Copyright (C) 2018-2019 Cadence Design Systems.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Pawel Jez <pjez@cadence.com>,
+ *          Pawel Laszczak <pawell@cadence.com>
+ *          Peter Chen <peter.chen@nxp.com>
+ */
+
+/*
+ * Work around 1:
+ * At some situations, the controller may get stale data address in TRB
+ * at below sequences:
+ * 1. Controller read TRB includes data address
+ * 2. Software updates TRBs includes data address and Cycle bit
+ * 3. Controller read TRB which includes Cycle bit
+ * 4. DMA run with stale data address
+ *
+ * To fix this problem, driver needs to make the first TRB in TD as invalid.
+ * After preparing all TRBs driver needs to check the position of DMA and
+ * if the DMA point to the first just added TRB and doorbell is 1,
+ * then driver must defer making this TRB as valid. This TRB will be make
+ * as valid during adding next TRB only if DMA is stopped or at TRBERR
+ * interrupt.
+ *
+ * Issue has been fixed in DEV_VER_V3 version of controller.
+ *
+ * Work around 2:
+ * Controller for OUT endpoints has shared on-chip buffers for all incoming
+ * packets, including ep0out. It's FIFO buffer, so packets must be handle by DMA
+ * in correct order. If the first packet in the buffer will not be handled,
+ * then the following packets directed for other endpoints and  functions
+ * will be blocked.
+ * Additionally the packets directed to one endpoint can block entire on-chip
+ * buffers. In this case transfer to other endpoints also will blocked.
+ *
+ * To resolve this issue after raising the descriptor missing interrupt
+ * driver prepares internal usb_request object and use it to arm DMA transfer.
+ *
+ * The problematic situation was observed in case when endpoint has been enabled
+ * but no usb_request were queued. Driver try detects such endpoints and will
+ * use this workaround only for these endpoint.
+ *
+ * Driver use limited number of buffer. This number can be set by macro
+ * CDNS3_WA2_NUM_BUFFERS.
+ *
+ * Such blocking situation was observed on ACM gadget. For this function
+ * host send OUT data packet but ACM function is not prepared for this packet.
+ * It's cause that buffer placed in on chip memory block transfer to other
+ * endpoints.
+ *
+ * Issue has been fixed in DEV_VER_V2 version of controller.
+ *
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/usb/gadget.h>
+#include <linux/module.h>
+#include <linux/iopoll.h>
+
+#include "core.h"
+#include "gadget-export.h"
+#include "gadget.h"
+#include "trace.h"
+#include "drd.h"
+
+static int __cdns3_gadget_ep_queue(struct usb_ep *ep,
+				   struct usb_request *request,
+				   gfp_t gfp_flags);
+
+static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+				 struct usb_request *request);
+
+static int cdns3_ep_run_stream_transfer(struct cdns3_endpoint *priv_ep,
+					struct usb_request *request);
+
+/**
+ * cdns3_clear_register_bit - clear bit in given register.
+ * @ptr: address of device controller register to be read and changed
+ * @mask: bits requested to clar
+ */
+static void cdns3_clear_register_bit(void __iomem *ptr, u32 mask)
+{
+	mask = readl(ptr) & ~mask;
+	writel(mask, ptr);
+}
+
+/**
+ * cdns3_set_register_bit - set bit in given register.
+ * @ptr: address of device controller register to be read and changed
+ * @mask: bits requested to set
+ */
+void cdns3_set_register_bit(void __iomem *ptr, u32 mask)
+{
+	mask = readl(ptr) | mask;
+	writel(mask, ptr);
+}
+
+/**
+ * cdns3_ep_addr_to_index - Macro converts endpoint address to
+ * index of endpoint object in cdns3_device.eps[] container
+ * @ep_addr: endpoint address for which endpoint object is required
+ *
+ */
+u8 cdns3_ep_addr_to_index(u8 ep_addr)
+{
+	return (((ep_addr & 0x7F)) + ((ep_addr & USB_DIR_IN) ? 16 : 0));
+}
+
+static int cdns3_get_dma_pos(struct cdns3_device *priv_dev,
+			     struct cdns3_endpoint *priv_ep)
+{
+	int dma_index;
+
+	dma_index = readl(&priv_dev->regs->ep_traddr) - priv_ep->trb_pool_dma;
+
+	return dma_index / TRB_SIZE;
+}
+
+/**
+ * cdns3_next_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct usb_request *cdns3_next_request(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct usb_request, list);
+}
+
+/**
+ * cdns3_next_align_buf - returns next buffer from list
+ * @list: list containing buffers
+ *
+ * Returns buffer or NULL if no buffers in list
+ */
+static struct cdns3_aligned_buf *cdns3_next_align_buf(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct cdns3_aligned_buf, list);
+}
+
+/**
+ * cdns3_next_priv_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+static struct cdns3_request *cdns3_next_priv_request(struct list_head *list)
+{
+	return list_first_entry_or_null(list, struct cdns3_request, list);
+}
+
+/**
+ * select_ep - selects endpoint
+ * @priv_dev:  extended gadget object
+ * @ep: endpoint address
+ */
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep)
+{
+	if (priv_dev->selected_ep == ep)
+		return;
+
+	priv_dev->selected_ep = ep;
+	writel(ep, &priv_dev->regs->ep_sel);
+}
+
+/**
+ * cdns3_get_tdl - gets current tdl for selected endpoint.
+ * @priv_dev:  extended gadget object
+ *
+ * Before calling this function the appropriate endpoint must
+ * be selected by means of cdns3_select_ep function.
+ */
+static int cdns3_get_tdl(struct cdns3_device *priv_dev)
+{
+	if (priv_dev->dev_ver < DEV_VER_V3)
+		return EP_CMD_TDL_GET(readl(&priv_dev->regs->ep_cmd));
+	else
+		return readl(&priv_dev->regs->ep_tdl);
+}
+
+dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
+				 struct cdns3_trb *trb)
+{
+	u32 offset = (char *)trb - (char *)priv_ep->trb_pool;
+
+	return priv_ep->trb_pool_dma + offset;
+}
+
+static int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
+{
+	switch (priv_ep->type) {
+	case USB_ENDPOINT_XFER_ISOC:
+		return TRB_ISO_RING_SIZE;
+	case USB_ENDPOINT_XFER_CONTROL:
+		return TRB_CTRL_RING_SIZE;
+	default:
+		if (priv_ep->use_streams)
+			return TRB_STREAM_RING_SIZE;
+		else
+			return TRB_RING_SIZE;
+	}
+}
+
+static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	if (priv_ep->trb_pool) {
+		dma_free_coherent(priv_dev->sysdev,
+				  cdns3_ring_size(priv_ep),
+				  priv_ep->trb_pool, priv_ep->trb_pool_dma);
+		priv_ep->trb_pool = NULL;
+	}
+}
+
+/**
+ * cdns3_allocate_trb_pool - Allocates TRB's pool for selected endpoint
+ * @priv_ep:  endpoint object
+ *
+ * Function will return 0 on success or -ENOMEM on allocation error
+ */
+int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	int ring_size = cdns3_ring_size(priv_ep);
+	int num_trbs = ring_size / TRB_SIZE;
+	struct cdns3_trb *link_trb;
+
+	if (priv_ep->trb_pool && priv_ep->alloc_ring_size < ring_size)
+		cdns3_free_trb_pool(priv_ep);
+
+	if (!priv_ep->trb_pool) {
+		priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,
+						       ring_size,
+						       &priv_ep->trb_pool_dma,
+						       GFP_DMA32 | GFP_ATOMIC);
+		if (!priv_ep->trb_pool)
+			return -ENOMEM;
+
+		priv_ep->alloc_ring_size = ring_size;
+	}
+
+	memset(priv_ep->trb_pool, 0, ring_size);
+
+	priv_ep->num_trbs = num_trbs;
+
+	if (!priv_ep->num)
+		return 0;
+
+	/* Initialize the last TRB as Link TRB */
+	link_trb = (priv_ep->trb_pool + (priv_ep->num_trbs - 1));
+
+	if (priv_ep->use_streams) {
+		/*
+		 * For stream capable endpoints driver use single correct TRB.
+		 * The last trb has zeroed cycle bit
+		 */
+		link_trb->control = 0;
+	} else {
+		link_trb->buffer = cpu_to_le32(TRB_BUFFER(priv_ep->trb_pool_dma));
+		link_trb->control = cpu_to_le32(TRB_CYCLE | TRB_TYPE(TRB_LINK) | TRB_TOGGLE);
+	}
+	return 0;
+}
+
+/**
+ * cdns3_ep_stall_flush - Stalls and flushes selected endpoint
+ * @priv_ep: endpoint object
+ *
+ * Endpoint must be selected before call to this function
+ */
+static void cdns3_ep_stall_flush(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	int val;
+
+	trace_cdns3_halt(priv_ep, 1, 1);
+
+	writel(EP_CMD_DFLUSH | EP_CMD_ERDY | EP_CMD_SSTALL,
+	       &priv_dev->regs->ep_cmd);
+
+	/* wait for DFLUSH cleared */
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+				  !(val & EP_CMD_DFLUSH), 1, 1000);
+	priv_ep->flags |= EP_STALLED;
+	priv_ep->flags &= ~EP_STALL_PENDING;
+}
+
+/**
+ * cdns3_hw_reset_eps_config - reset endpoints configuration kept by controller.
+ * @priv_dev: extended gadget object
+ */
+void cdns3_hw_reset_eps_config(struct cdns3_device *priv_dev)
+{
+	int i;
+
+	writel(USB_CONF_CFGRST, &priv_dev->regs->usb_conf);
+
+	cdns3_allow_enable_l1(priv_dev, 0);
+	priv_dev->hw_configured_flag = 0;
+	priv_dev->onchip_used_size = 0;
+	priv_dev->out_mem_is_allocated = 0;
+	priv_dev->wait_for_setup = 0;
+	priv_dev->using_streams = 0;
+
+	for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++)
+		if (priv_dev->eps[i])
+			priv_dev->eps[i]->flags &= ~EP_CONFIGURED;
+}
+
+/**
+ * cdns3_ep_inc_trb - increment a trb index.
+ * @index: Pointer to the TRB index to increment.
+ * @cs: Cycle state
+ * @trb_in_seg: number of TRBs in segment
+ *
+ * The index should never point to the link TRB. After incrementing,
+ * if it is point to the link TRB, wrap around to the beginning and revert
+ * cycle state bit The
+ * link TRB is always at the last TRB entry.
+ */
+static void cdns3_ep_inc_trb(int *index, u8 *cs, int trb_in_seg)
+{
+	(*index)++;
+	if (*index == (trb_in_seg - 1)) {
+		*index = 0;
+		*cs ^=  1;
+	}
+}
+
+/**
+ * cdns3_ep_inc_enq - increment endpoint's enqueue pointer
+ * @priv_ep: The endpoint whose enqueue pointer we're incrementing
+ */
+static void cdns3_ep_inc_enq(struct cdns3_endpoint *priv_ep)
+{
+	priv_ep->free_trbs--;
+	cdns3_ep_inc_trb(&priv_ep->enqueue, &priv_ep->pcs, priv_ep->num_trbs);
+}
+
+/**
+ * cdns3_ep_inc_deq - increment endpoint's dequeue pointer
+ * @priv_ep: The endpoint whose dequeue pointer we're incrementing
+ */
+static void cdns3_ep_inc_deq(struct cdns3_endpoint *priv_ep)
+{
+	priv_ep->free_trbs++;
+	cdns3_ep_inc_trb(&priv_ep->dequeue, &priv_ep->ccs, priv_ep->num_trbs);
+}
+
+/**
+ * cdns3_allow_enable_l1 - enable/disable permits to transition to L1.
+ * @priv_dev: Extended gadget object
+ * @enable: Enable/disable permit to transition to L1.
+ *
+ * If bit USB_CONF_L1EN is set and device receive Extended Token packet,
+ * then controller answer with ACK handshake.
+ * If bit USB_CONF_L1DS is set and device receive Extended Token packet,
+ * then controller answer with NYET handshake.
+ */
+void cdns3_allow_enable_l1(struct cdns3_device *priv_dev, int enable)
+{
+	if (enable)
+		writel(USB_CONF_L1EN, &priv_dev->regs->usb_conf);
+	else
+		writel(USB_CONF_L1DS, &priv_dev->regs->usb_conf);
+}
+
+enum usb_device_speed cdns3_get_speed(struct cdns3_device *priv_dev)
+{
+	u32 reg;
+
+	reg = readl(&priv_dev->regs->usb_sts);
+
+	if (DEV_SUPERSPEED(reg))
+		return USB_SPEED_SUPER;
+	else if (DEV_HIGHSPEED(reg))
+		return USB_SPEED_HIGH;
+	else if (DEV_FULLSPEED(reg))
+		return USB_SPEED_FULL;
+	else if (DEV_LOWSPEED(reg))
+		return USB_SPEED_LOW;
+	return USB_SPEED_UNKNOWN;
+}
+
+/**
+ * cdns3_start_all_request - add to ring all request not started
+ * @priv_dev: Extended gadget object
+ * @priv_ep: The endpoint for whom request will be started.
+ *
+ * Returns return ENOMEM if transfer ring i not enough TRBs to start
+ *         all requests.
+ */
+static int cdns3_start_all_request(struct cdns3_device *priv_dev,
+				   struct cdns3_endpoint *priv_ep)
+{
+	struct usb_request *request;
+	int ret = 0;
+	u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+
+	/*
+	 * If the last pending transfer is INTERNAL
+	 * OR streams are enabled for this endpoint
+	 * do NOT start new transfer till the last one is pending
+	 */
+	if (!pending_empty) {
+		struct cdns3_request *priv_req;
+
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+		priv_req = to_cdns3_request(request);
+		if ((priv_req->flags & REQUEST_INTERNAL) ||
+		    (priv_ep->flags & EP_TDLCHK_EN) ||
+			priv_ep->use_streams) {
+			dev_dbg(priv_dev->dev, "Blocking external request\n");
+			return ret;
+		}
+	}
+
+	while (!list_empty(&priv_ep->deferred_req_list)) {
+		request = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		if (!priv_ep->use_streams) {
+			ret = cdns3_ep_run_transfer(priv_ep, request);
+		} else {
+			priv_ep->stream_sg_idx = 0;
+			ret = cdns3_ep_run_stream_transfer(priv_ep, request);
+		}
+		if (ret)
+			return ret;
+
+		list_del(&request->list);
+		list_add_tail(&request->list,
+			      &priv_ep->pending_req_list);
+		if (request->stream_id != 0 || (priv_ep->flags & EP_TDLCHK_EN))
+			break;
+	}
+
+	priv_ep->flags &= ~EP_RING_FULL;
+	return ret;
+}
+
+/*
+ * WA2: Set flag for all not ISOC OUT endpoints. If this flag is set
+ * driver try to detect whether endpoint need additional internal
+ * buffer for unblocking on-chip FIFO buffer. This flag will be cleared
+ * if before first DESCMISS interrupt the DMA will be armed.
+ */
+#define cdns3_wa2_enable_detection(priv_dev, priv_ep, reg) do { \
+	if (!priv_ep->dir && priv_ep->type != USB_ENDPOINT_XFER_ISOC) { \
+		priv_ep->flags |= EP_QUIRK_EXTRA_BUF_DET; \
+		(reg) |= EP_STS_EN_DESCMISEN; \
+	} } while (0)
+
+static void __cdns3_descmiss_copy_data(struct usb_request *request,
+	struct usb_request *descmiss_req)
+{
+	int length = request->actual + descmiss_req->actual;
+	struct scatterlist *s = request->sg;
+
+	if (!s) {
+		if (length <= request->length) {
+			memcpy(&((u8 *)request->buf)[request->actual],
+			       descmiss_req->buf,
+			       descmiss_req->actual);
+			request->actual = length;
+		} else {
+			/* It should never occures */
+			request->status = -ENOMEM;
+		}
+	} else {
+		if (length <= sg_dma_len(s)) {
+			void *p = phys_to_virt(sg_dma_address(s));
+
+			memcpy(&((u8 *)p)[request->actual],
+				descmiss_req->buf,
+				descmiss_req->actual);
+			request->actual = length;
+		} else {
+			request->status = -ENOMEM;
+		}
+	}
+}
+
+/**
+ * cdns3_wa2_descmiss_copy_data copy data from internal requests to
+ * request queued by class driver.
+ * @priv_ep: extended endpoint object
+ * @request: request object
+ */
+static void cdns3_wa2_descmiss_copy_data(struct cdns3_endpoint *priv_ep,
+					 struct usb_request *request)
+{
+	struct usb_request *descmiss_req;
+	struct cdns3_request *descmiss_priv_req;
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		int chunk_end;
+
+		descmiss_priv_req =
+			cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+		descmiss_req = &descmiss_priv_req->request;
+
+		/* driver can't touch pending request */
+		if (descmiss_priv_req->flags & REQUEST_PENDING)
+			break;
+
+		chunk_end = descmiss_priv_req->flags & REQUEST_INTERNAL_CH;
+		request->status = descmiss_req->status;
+		__cdns3_descmiss_copy_data(request, descmiss_req);
+		list_del_init(&descmiss_priv_req->list);
+		kfree(descmiss_req->buf);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, descmiss_req);
+		--priv_ep->wa2_counter;
+
+		if (!chunk_end)
+			break;
+	}
+}
+
+static struct usb_request *cdns3_wa2_gadget_giveback(struct cdns3_device *priv_dev,
+						     struct cdns3_endpoint *priv_ep,
+						     struct cdns3_request *priv_req)
+{
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN &&
+	    priv_req->flags & REQUEST_INTERNAL) {
+		struct usb_request *req;
+
+		req = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		priv_ep->descmis_req = NULL;
+
+		if (!req)
+			return NULL;
+
+		/* unmap the gadget request before copying data */
+		usb_gadget_unmap_request_by_dev(priv_dev->sysdev, req,
+						priv_ep->dir);
+
+		cdns3_wa2_descmiss_copy_data(priv_ep, req);
+		if (!(priv_ep->flags & EP_QUIRK_END_TRANSFER) &&
+		    req->length != req->actual) {
+			/* wait for next part of transfer */
+			/* re-map the gadget request buffer*/
+			usb_gadget_map_request_by_dev(priv_dev->sysdev, req,
+				usb_endpoint_dir_in(priv_ep->endpoint.desc));
+			return NULL;
+		}
+
+		if (req->status == -EINPROGRESS)
+			req->status = 0;
+
+		list_del_init(&req->list);
+		cdns3_start_all_request(priv_dev, priv_ep);
+		return req;
+	}
+
+	return &priv_req->request;
+}
+
+static int cdns3_wa2_gadget_ep_queue(struct cdns3_device *priv_dev,
+				     struct cdns3_endpoint *priv_ep,
+				     struct cdns3_request *priv_req)
+{
+	int deferred = 0;
+
+	/*
+	 * If transfer was queued before DESCMISS appear than we
+	 * can disable handling of DESCMISS interrupt. Driver assumes that it
+	 * can disable special treatment for this endpoint.
+	 */
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+		u32 reg;
+
+		cdns3_select_ep(priv_dev, priv_ep->num | priv_ep->dir);
+		priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+		reg = readl(&priv_dev->regs->ep_sts_en);
+		reg &= ~EP_STS_EN_DESCMISEN;
+		trace_cdns3_wa2(priv_ep, "workaround disabled\n");
+		writel(reg, &priv_dev->regs->ep_sts_en);
+	}
+
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+		u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+		u8 descmiss_empty = list_empty(&priv_ep->wa2_descmiss_req_list);
+
+		/*
+		 *  DESCMISS transfer has been finished, so data will be
+		 *  directly copied from internal allocated usb_request
+		 *  objects.
+		 */
+		if (pending_empty && !descmiss_empty &&
+		    !(priv_req->flags & REQUEST_INTERNAL)) {
+			cdns3_wa2_descmiss_copy_data(priv_ep,
+						     &priv_req->request);
+
+			trace_cdns3_wa2(priv_ep, "get internal stored data");
+
+			list_add_tail(&priv_req->request.list,
+				      &priv_ep->pending_req_list);
+			cdns3_gadget_giveback(priv_ep, priv_req,
+					      priv_req->request.status);
+
+			/*
+			 * Intentionally driver returns positive value as
+			 * correct value. It informs that transfer has
+			 * been finished.
+			 */
+			return EINPROGRESS;
+		}
+
+		/*
+		 * Driver will wait for completion DESCMISS transfer,
+		 * before starts new, not DESCMISS transfer.
+		 */
+		if (!pending_empty && !descmiss_empty) {
+			trace_cdns3_wa2(priv_ep, "wait for pending transfer\n");
+			deferred = 1;
+		}
+
+		if (priv_req->flags & REQUEST_INTERNAL)
+			list_add_tail(&priv_req->list,
+				      &priv_ep->wa2_descmiss_req_list);
+	}
+
+	return deferred;
+}
+
+static void cdns3_wa2_remove_old_request(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		u8 chain;
+
+		priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+		chain = !!(priv_req->flags & REQUEST_INTERNAL_CH);
+
+		trace_cdns3_wa2(priv_ep, "removes eldest request");
+
+		kfree(priv_req->request.buf);
+		list_del_init(&priv_req->list);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+					     &priv_req->request);
+		--priv_ep->wa2_counter;
+
+		if (!chain)
+			break;
+	}
+}
+
+/**
+ * cdns3_wa2_descmissing_packet - handles descriptor missing event.
+ * @priv_ep: extended gadget object
+ *
+ * This function is used only for WA2. For more information see Work around 2
+ * description.
+ */
+static void cdns3_wa2_descmissing_packet(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+	struct usb_request *request;
+	u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+
+	/* check for pending transfer */
+	if (!pending_empty) {
+		trace_cdns3_wa2(priv_ep, "Ignoring Descriptor missing IRQ\n");
+		return;
+	}
+
+	if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+		priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+		priv_ep->flags |= EP_QUIRK_EXTRA_BUF_EN;
+	}
+
+	trace_cdns3_wa2(priv_ep, "Description Missing detected\n");
+
+	if (priv_ep->wa2_counter >= CDNS3_WA2_NUM_BUFFERS) {
+		trace_cdns3_wa2(priv_ep, "WA2 overflow\n");
+		cdns3_wa2_remove_old_request(priv_ep);
+	}
+
+	request = cdns3_gadget_ep_alloc_request(&priv_ep->endpoint,
+						GFP_ATOMIC);
+	if (!request)
+		goto err;
+
+	priv_req = to_cdns3_request(request);
+	priv_req->flags |= REQUEST_INTERNAL;
+
+	/* if this field is still assigned it indicate that transfer related
+	 * with this request has not been finished yet. Driver in this
+	 * case simply allocate next request and assign flag REQUEST_INTERNAL_CH
+	 * flag to previous one. It will indicate that current request is
+	 * part of the previous one.
+	 */
+	if (priv_ep->descmis_req)
+		priv_ep->descmis_req->flags |= REQUEST_INTERNAL_CH;
+
+	priv_req->request.buf = kzalloc(CDNS3_DESCMIS_BUF_SIZE,
+					GFP_ATOMIC);
+	priv_ep->wa2_counter++;
+
+	if (!priv_req->request.buf) {
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+		goto err;
+	}
+
+	priv_req->request.length = CDNS3_DESCMIS_BUF_SIZE;
+	priv_ep->descmis_req = priv_req;
+
+	__cdns3_gadget_ep_queue(&priv_ep->endpoint,
+				&priv_ep->descmis_req->request,
+				GFP_ATOMIC);
+
+	return;
+
+err:
+	dev_err(priv_ep->cdns3_dev->dev,
+		"Failed: No sufficient memory for DESCMIS\n");
+}
+
+static void cdns3_wa2_reset_tdl(struct cdns3_device *priv_dev)
+{
+	u16 tdl = EP_CMD_TDL_GET(readl(&priv_dev->regs->ep_cmd));
+
+	if (tdl) {
+		u16 reset_val = EP_CMD_TDL_MAX + 1 - tdl;
+
+		writel(EP_CMD_TDL_SET(reset_val) | EP_CMD_STDL,
+		       &priv_dev->regs->ep_cmd);
+	}
+}
+
+static void cdns3_wa2_check_outq_status(struct cdns3_device *priv_dev)
+{
+	u32 ep_sts_reg;
+
+	/* select EP0-out */
+	cdns3_select_ep(priv_dev, 0);
+
+	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+
+	if (EP_STS_OUTQ_VAL(ep_sts_reg)) {
+		u32 outq_ep_num = EP_STS_OUTQ_NO(ep_sts_reg);
+		struct cdns3_endpoint *outq_ep = priv_dev->eps[outq_ep_num];
+
+		if ((outq_ep->flags & EP_ENABLED) && !(outq_ep->use_streams) &&
+		    outq_ep->type != USB_ENDPOINT_XFER_ISOC && outq_ep_num) {
+			u8 pending_empty = list_empty(&outq_ep->pending_req_list);
+
+			if ((outq_ep->flags & EP_QUIRK_EXTRA_BUF_DET) ||
+			    (outq_ep->flags & EP_QUIRK_EXTRA_BUF_EN) ||
+			    !pending_empty) {
+			} else {
+				u32 ep_sts_en_reg;
+				u32 ep_cmd_reg;
+
+				cdns3_select_ep(priv_dev, outq_ep->num |
+						outq_ep->dir);
+				ep_sts_en_reg = readl(&priv_dev->regs->ep_sts_en);
+				ep_cmd_reg = readl(&priv_dev->regs->ep_cmd);
+
+				outq_ep->flags |= EP_TDLCHK_EN;
+				cdns3_set_register_bit(&priv_dev->regs->ep_cfg,
+						       EP_CFG_TDL_CHK);
+
+				cdns3_wa2_enable_detection(priv_dev, outq_ep,
+							   ep_sts_en_reg);
+				writel(ep_sts_en_reg,
+				       &priv_dev->regs->ep_sts_en);
+				/* reset tdl value to zero */
+				cdns3_wa2_reset_tdl(priv_dev);
+				/*
+				 * Memory barrier - Reset tdl before ringing the
+				 * doorbell.
+				 */
+				wmb();
+				if (EP_CMD_DRDY & ep_cmd_reg) {
+					trace_cdns3_wa2(outq_ep, "Enabling WA2 skipping doorbell\n");
+
+				} else {
+					trace_cdns3_wa2(outq_ep, "Enabling WA2 ringing doorbell\n");
+					/*
+					 * ring doorbell to generate DESCMIS irq
+					 */
+					writel(EP_CMD_DRDY,
+					       &priv_dev->regs->ep_cmd);
+				}
+			}
+		}
+	}
+}
+
+/**
+ * cdns3_gadget_giveback - call struct usb_request's ->complete callback
+ * @priv_ep: The endpoint to whom the request belongs to
+ * @priv_req: The request we're giving back
+ * @status: completion code for the request
+ *
+ * Must be called with controller's lock held and interrupts disabled. This
+ * function will unmap @req and call its ->complete() callback to notify upper
+ * layers that it has completed.
+ */
+void cdns3_gadget_giveback(struct cdns3_endpoint *priv_ep,
+			   struct cdns3_request *priv_req,
+			   int status)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct usb_request *request = &priv_req->request;
+
+	list_del_init(&request->list);
+
+	if (request->status == -EINPROGRESS)
+		request->status = status;
+
+	usb_gadget_unmap_request_by_dev(priv_dev->sysdev, request,
+					priv_ep->dir);
+
+	if ((priv_req->flags & REQUEST_UNALIGNED) &&
+	    priv_ep->dir == USB_DIR_OUT && !request->status)
+		memcpy(request->buf, priv_req->aligned_buf->buf,
+		       request->length);
+
+	priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
+	/* All TRBs have finished, clear the counter */
+	priv_req->finished_trb = 0;
+	trace_cdns3_gadget_giveback(priv_req);
+
+	if (priv_dev->dev_ver < DEV_VER_V2) {
+		request = cdns3_wa2_gadget_giveback(priv_dev, priv_ep,
+						    priv_req);
+		if (!request)
+			return;
+	}
+
+	if (request->complete) {
+		spin_unlock(&priv_dev->lock);
+		usb_gadget_giveback_request(&priv_ep->endpoint,
+					    request);
+		spin_lock(&priv_dev->lock);
+	}
+
+	if (request->buf == priv_dev->zlp_buf)
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+}
+
+static void cdns3_wa1_restore_cycle_bit(struct cdns3_endpoint *priv_ep)
+{
+	/* Work around for stale data address in TRB*/
+	if (priv_ep->wa1_set) {
+		trace_cdns3_wa1(priv_ep, "restore cycle bit");
+
+		priv_ep->wa1_set = 0;
+		priv_ep->wa1_trb_index = 0xFFFF;
+		if (priv_ep->wa1_cycle_bit) {
+			priv_ep->wa1_trb->control =
+				priv_ep->wa1_trb->control | cpu_to_le32(0x1);
+		} else {
+			priv_ep->wa1_trb->control =
+				priv_ep->wa1_trb->control & cpu_to_le32(~0x1);
+		}
+	}
+}
+
+static void cdns3_free_aligned_request_buf(struct work_struct *work)
+{
+	struct cdns3_device *priv_dev = container_of(work, struct cdns3_device,
+					aligned_buf_wq);
+	struct cdns3_aligned_buf *buf, *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	list_for_each_entry_safe(buf, tmp, &priv_dev->aligned_buf_list, list) {
+		if (!buf->in_use) {
+			list_del(&buf->list);
+
+			/*
+			 * Re-enable interrupts to free DMA capable memory.
+			 * Driver can't free this memory with disabled
+			 * interrupts.
+			 */
+			spin_unlock_irqrestore(&priv_dev->lock, flags);
+			dma_free_coherent(priv_dev->sysdev, buf->size,
+					  buf->buf, buf->dma);
+			kfree(buf);
+			spin_lock_irqsave(&priv_dev->lock, flags);
+		}
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+}
+
+static int cdns3_prepare_aligned_request_buf(struct cdns3_request *priv_req)
+{
+	struct cdns3_endpoint *priv_ep = priv_req->priv_ep;
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_aligned_buf *buf;
+
+	/* check if buffer is aligned to 8. */
+	if (!((uintptr_t)priv_req->request.buf & 0x7))
+		return 0;
+
+	buf = priv_req->aligned_buf;
+
+	if (!buf || priv_req->request.length > buf->size) {
+		buf = kzalloc(sizeof(*buf), GFP_ATOMIC);
+		if (!buf)
+			return -ENOMEM;
+
+		buf->size = priv_req->request.length;
+
+		buf->buf = dma_alloc_coherent(priv_dev->sysdev,
+					      buf->size,
+					      &buf->dma,
+					      GFP_ATOMIC);
+		if (!buf->buf) {
+			kfree(buf);
+			return -ENOMEM;
+		}
+
+		if (priv_req->aligned_buf) {
+			trace_cdns3_free_aligned_request(priv_req);
+			priv_req->aligned_buf->in_use = 0;
+			queue_work(system_freezable_wq,
+				   &priv_dev->aligned_buf_wq);
+		}
+
+		buf->in_use = 1;
+		priv_req->aligned_buf = buf;
+
+		list_add_tail(&buf->list,
+			      &priv_dev->aligned_buf_list);
+	}
+
+	if (priv_ep->dir == USB_DIR_IN) {
+		memcpy(buf->buf, priv_req->request.buf,
+		       priv_req->request.length);
+	}
+
+	priv_req->flags |= REQUEST_UNALIGNED;
+	trace_cdns3_prepare_aligned_request(priv_req);
+
+	return 0;
+}
+
+static int cdns3_wa1_update_guard(struct cdns3_endpoint *priv_ep,
+				  struct cdns3_trb *trb)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	if (!priv_ep->wa1_set) {
+		u32 doorbell;
+
+		doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+		if (doorbell) {
+			priv_ep->wa1_cycle_bit = priv_ep->pcs ? TRB_CYCLE : 0;
+			priv_ep->wa1_set = 1;
+			priv_ep->wa1_trb = trb;
+			priv_ep->wa1_trb_index = priv_ep->enqueue;
+			trace_cdns3_wa1(priv_ep, "set guard");
+			return 0;
+		}
+	}
+	return 1;
+}
+
+static void cdns3_wa1_tray_restore_cycle_bit(struct cdns3_device *priv_dev,
+					     struct cdns3_endpoint *priv_ep)
+{
+	int dma_index;
+	u32 doorbell;
+
+	doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+	dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+	if (!doorbell || dma_index != priv_ep->wa1_trb_index)
+		cdns3_wa1_restore_cycle_bit(priv_ep);
+}
+
+static int cdns3_ep_run_stream_transfer(struct cdns3_endpoint *priv_ep,
+					struct usb_request *request)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *trb;
+	dma_addr_t trb_dma;
+	int address;
+	u32 control;
+	u32 length;
+	u32 tdl;
+	unsigned int sg_idx = priv_ep->stream_sg_idx;
+
+	priv_req = to_cdns3_request(request);
+	address = priv_ep->endpoint.desc->bEndpointAddress;
+
+	priv_ep->flags |= EP_PENDING_REQUEST;
+
+	/* must allocate buffer aligned to 8 */
+	if (priv_req->flags & REQUEST_UNALIGNED)
+		trb_dma = priv_req->aligned_buf->dma;
+	else
+		trb_dma = request->dma;
+
+	/*  For stream capable endpoints driver use only single TD. */
+	trb = priv_ep->trb_pool + priv_ep->enqueue;
+	priv_req->start_trb = priv_ep->enqueue;
+	priv_req->end_trb = priv_req->start_trb;
+	priv_req->trb = trb;
+
+	cdns3_select_ep(priv_ep->cdns3_dev, address);
+
+	control = TRB_TYPE(TRB_NORMAL) | TRB_CYCLE |
+		  TRB_STREAM_ID(priv_req->request.stream_id) | TRB_ISP;
+
+	if (!request->num_sgs) {
+		trb->buffer = cpu_to_le32(TRB_BUFFER(trb_dma));
+		length = request->length;
+	} else {
+		trb->buffer = cpu_to_le32(TRB_BUFFER(request->sg[sg_idx].dma_address));
+		length = request->sg[sg_idx].length;
+	}
+
+	tdl = DIV_ROUND_UP(length, priv_ep->endpoint.maxpacket);
+
+	trb->length = cpu_to_le32(TRB_BURST_LEN(16) | TRB_LEN(length));
+
+	/*
+	 * For DEV_VER_V2 controller version we have enabled
+	 * USB_CONF2_EN_TDL_TRB in DMULT configuration.
+	 * This enables TDL calculation based on TRB, hence setting TDL in TRB.
+	 */
+	if (priv_dev->dev_ver >= DEV_VER_V2) {
+		if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+			trb->length |= cpu_to_le32(TRB_TDL_SS_SIZE(tdl));
+	}
+	priv_req->flags |= REQUEST_PENDING;
+
+	trb->control = cpu_to_le32(control);
+
+	trace_cdns3_prepare_trb(priv_ep, priv_req->trb);
+
+	/*
+	 * Memory barrier - Cycle Bit must be set before trb->length  and
+	 * trb->buffer fields.
+	 */
+	wmb();
+
+	/* always first element */
+	writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma),
+	       &priv_dev->regs->ep_traddr);
+
+	if (!(priv_ep->flags & EP_STALLED)) {
+		trace_cdns3_ring(priv_ep);
+		/*clearing TRBERR and EP_STS_DESCMIS before seting DRDY*/
+		writel(EP_STS_TRBERR | EP_STS_DESCMIS, &priv_dev->regs->ep_sts);
+
+		priv_ep->prime_flag = false;
+
+		/*
+		 * Controller version DEV_VER_V2 tdl calculation
+		 * is based on TRB
+		 */
+
+		if (priv_dev->dev_ver < DEV_VER_V2)
+			writel(EP_CMD_TDL_SET(tdl) | EP_CMD_STDL,
+			       &priv_dev->regs->ep_cmd);
+		else if (priv_dev->dev_ver > DEV_VER_V2)
+			writel(tdl, &priv_dev->regs->ep_tdl);
+
+		priv_ep->last_stream_id = priv_req->request.stream_id;
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+		writel(EP_CMD_ERDY_SID(priv_req->request.stream_id) |
+		       EP_CMD_ERDY, &priv_dev->regs->ep_cmd);
+
+		trace_cdns3_doorbell_epx(priv_ep->name,
+					 readl(&priv_dev->regs->ep_traddr));
+	}
+
+	/* WORKAROUND for transition to L0 */
+	__cdns3_gadget_wakeup(priv_dev);
+
+	return 0;
+}
+
+static void cdns3_rearm_drdy_if_needed(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	if (priv_dev->dev_ver < DEV_VER_V3)
+		return;
+
+	if (readl(&priv_dev->regs->ep_sts) & EP_STS_TRBERR) {
+		writel(EP_STS_TRBERR, &priv_dev->regs->ep_sts);
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+	}
+}
+
+/**
+ * cdns3_ep_run_transfer - start transfer on no-default endpoint hardware
+ * @priv_ep: endpoint object
+ * @request: request object
+ *
+ * Returns zero on success or negative value on failure
+ */
+static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+				 struct usb_request *request)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *trb;
+	struct cdns3_trb *link_trb = NULL;
+	dma_addr_t trb_dma;
+	u32 togle_pcs = 1;
+	int sg_iter = 0;
+	int num_trb;
+	int address;
+	u32 control;
+	int pcs;
+	u16 total_tdl = 0;
+	struct scatterlist *s = NULL;
+	bool sg_supported = !!(request->num_mapped_sgs);
+
+	if (priv_ep->type == USB_ENDPOINT_XFER_ISOC)
+		num_trb = priv_ep->interval;
+	else
+		num_trb = sg_supported ? request->num_mapped_sgs : 1;
+
+	if (num_trb > priv_ep->free_trbs) {
+		priv_ep->flags |= EP_RING_FULL;
+		return -ENOBUFS;
+	}
+
+	priv_req = to_cdns3_request(request);
+	address = priv_ep->endpoint.desc->bEndpointAddress;
+
+	priv_ep->flags |= EP_PENDING_REQUEST;
+
+	/* must allocate buffer aligned to 8 */
+	if (priv_req->flags & REQUEST_UNALIGNED)
+		trb_dma = priv_req->aligned_buf->dma;
+	else
+		trb_dma = request->dma;
+
+	trb = priv_ep->trb_pool + priv_ep->enqueue;
+	priv_req->start_trb = priv_ep->enqueue;
+	priv_req->trb = trb;
+
+	cdns3_select_ep(priv_ep->cdns3_dev, address);
+
+	/* prepare ring */
+	if ((priv_ep->enqueue + num_trb)  >= (priv_ep->num_trbs - 1)) {
+		int doorbell, dma_index;
+		u32 ch_bit = 0;
+
+		doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+		dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+		/* Driver can't update LINK TRB if it is current processed. */
+		if (doorbell && dma_index == priv_ep->num_trbs - 1) {
+			priv_ep->flags |= EP_DEFERRED_DRDY;
+			return -ENOBUFS;
+		}
+
+		/*updating C bt in  Link TRB before starting DMA*/
+		link_trb = priv_ep->trb_pool + (priv_ep->num_trbs - 1);
+		/*
+		 * For TRs size equal 2 enabling TRB_CHAIN for epXin causes
+		 * that DMA stuck at the LINK TRB.
+		 * On the other hand, removing TRB_CHAIN for longer TRs for
+		 * epXout cause that DMA stuck after handling LINK TRB.
+		 * To eliminate this strange behavioral driver set TRB_CHAIN
+		 * bit only for TR size > 2.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC ||
+		    TRBS_PER_SEGMENT > 2)
+			ch_bit = TRB_CHAIN;
+
+		link_trb->control = cpu_to_le32(((priv_ep->pcs) ? TRB_CYCLE : 0) |
+				    TRB_TYPE(TRB_LINK) | TRB_TOGGLE | ch_bit);
+	}
+
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		togle_pcs = cdns3_wa1_update_guard(priv_ep, trb);
+
+	if (sg_supported)
+		s = request->sg;
+
+	/* set incorrect Cycle Bit for first trb*/
+	control = priv_ep->pcs ? 0 : TRB_CYCLE;
+	trb->length = 0;
+	if (priv_dev->dev_ver >= DEV_VER_V2) {
+		u16 td_size;
+
+		td_size = DIV_ROUND_UP(request->length,
+				       priv_ep->endpoint.maxpacket);
+		if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+			trb->length = TRB_TDL_SS_SIZE(td_size);
+		else
+			control |= TRB_TDL_HS_SIZE(td_size);
+	}
+
+	do {
+		u32 length;
+
+		/* fill TRB */
+		control |= TRB_TYPE(TRB_NORMAL);
+		if (sg_supported) {
+			trb->buffer = cpu_to_le32(TRB_BUFFER(sg_dma_address(s)));
+			length = sg_dma_len(s);
+		} else {
+			trb->buffer = cpu_to_le32(TRB_BUFFER(trb_dma));
+			length = request->length;
+		}
+
+		if (priv_ep->flags & EP_TDLCHK_EN)
+			total_tdl += DIV_ROUND_UP(length,
+					       priv_ep->endpoint.maxpacket);
+
+		trb->length |= cpu_to_le32(TRB_BURST_LEN(priv_ep->trb_burst_size) |
+					TRB_LEN(length));
+		pcs = priv_ep->pcs ? TRB_CYCLE : 0;
+
+		/*
+		 * first trb should be prepared as last to avoid processing
+		 *  transfer to early
+		 */
+		if (sg_iter != 0)
+			control |= pcs;
+
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir) {
+			control |= TRB_IOC | TRB_ISP;
+		} else {
+			/* for last element in TD or in SG list */
+			if (sg_iter == (num_trb - 1) && sg_iter != 0)
+				control |= pcs | TRB_IOC | TRB_ISP;
+		}
+
+		if (sg_iter)
+			trb->control = cpu_to_le32(control);
+		else
+			priv_req->trb->control = cpu_to_le32(control);
+
+		if (sg_supported) {
+			trb->control |= TRB_ISP;
+			/* Don't set chain bit for last TRB */
+			if (sg_iter < num_trb - 1)
+				trb->control |= TRB_CHAIN;
+
+			s = sg_next(s);
+		}
+
+		control = 0;
+		++sg_iter;
+		priv_req->end_trb = priv_ep->enqueue;
+		cdns3_ep_inc_enq(priv_ep);
+		trb = priv_ep->trb_pool + priv_ep->enqueue;
+		trb->length = 0;
+	} while (sg_iter < num_trb);
+
+	trb = priv_req->trb;
+
+	priv_req->flags |= REQUEST_PENDING;
+	priv_req->num_of_trb = num_trb;
+
+	if (sg_iter == 1)
+		trb->control |= cpu_to_le32(TRB_IOC | TRB_ISP);
+
+	if (priv_dev->dev_ver < DEV_VER_V2 &&
+	    (priv_ep->flags & EP_TDLCHK_EN)) {
+		u16 tdl = total_tdl;
+		u16 old_tdl = EP_CMD_TDL_GET(readl(&priv_dev->regs->ep_cmd));
+
+		if (tdl > EP_CMD_TDL_MAX) {
+			tdl = EP_CMD_TDL_MAX;
+			priv_ep->pending_tdl = total_tdl - EP_CMD_TDL_MAX;
+		}
+
+		if (old_tdl < tdl) {
+			tdl -= old_tdl;
+			writel(EP_CMD_TDL_SET(tdl) | EP_CMD_STDL,
+			       &priv_dev->regs->ep_cmd);
+		}
+	}
+
+	/*
+	 * Memory barrier - cycle bit must be set before other filds in trb.
+	 */
+	wmb();
+
+	/* give the TD to the consumer*/
+	if (togle_pcs)
+		trb->control = trb->control ^ cpu_to_le32(1);
+
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		cdns3_wa1_tray_restore_cycle_bit(priv_dev, priv_ep);
+
+	if (num_trb > 1) {
+		int i = 0;
+
+		while (i < num_trb) {
+			trace_cdns3_prepare_trb(priv_ep, trb + i);
+			if (trb + i == link_trb) {
+				trb = priv_ep->trb_pool;
+				num_trb = num_trb - i;
+				i = 0;
+			} else {
+				i++;
+			}
+		}
+	} else {
+		trace_cdns3_prepare_trb(priv_ep, priv_req->trb);
+	}
+
+	/*
+	 * Memory barrier - Cycle Bit must be set before trb->length  and
+	 * trb->buffer fields.
+	 */
+	wmb();
+
+	/*
+	 * For DMULT mode we can set address to transfer ring only once after
+	 * enabling endpoint.
+	 */
+	if (priv_ep->flags & EP_UPDATE_EP_TRBADDR) {
+		/*
+		 * Until SW is not ready to handle the OUT transfer the ISO OUT
+		 * Endpoint should be disabled (EP_CFG.ENABLE = 0).
+		 * EP_CFG_ENABLE must be set before updating ep_traddr.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir &&
+		    !(priv_ep->flags & EP_QUIRK_ISO_OUT_EN)) {
+			priv_ep->flags |= EP_QUIRK_ISO_OUT_EN;
+			cdns3_set_register_bit(&priv_dev->regs->ep_cfg,
+					       EP_CFG_ENABLE);
+		}
+
+		writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma +
+					priv_req->start_trb * TRB_SIZE),
+					&priv_dev->regs->ep_traddr);
+
+		priv_ep->flags &= ~EP_UPDATE_EP_TRBADDR;
+	}
+
+	if (!priv_ep->wa1_set && !(priv_ep->flags & EP_STALLED)) {
+		trace_cdns3_ring(priv_ep);
+		/*clearing TRBERR and EP_STS_DESCMIS before seting DRDY*/
+		writel(EP_STS_TRBERR | EP_STS_DESCMIS, &priv_dev->regs->ep_sts);
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+		cdns3_rearm_drdy_if_needed(priv_ep);
+		trace_cdns3_doorbell_epx(priv_ep->name,
+					 readl(&priv_dev->regs->ep_traddr));
+	}
+
+	/* WORKAROUND for transition to L0 */
+	__cdns3_gadget_wakeup(priv_dev);
+
+	return 0;
+}
+
+void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct usb_ep *ep;
+
+	if (priv_dev->hw_configured_flag)
+		return;
+
+	writel(USB_CONF_CFGSET, &priv_dev->regs->usb_conf);
+
+	cdns3_set_register_bit(&priv_dev->regs->usb_conf,
+			       USB_CONF_U1EN | USB_CONF_U2EN);
+
+	priv_dev->hw_configured_flag = 1;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		if (ep->enabled) {
+			priv_ep = ep_to_cdns3_ep(ep);
+			cdns3_start_all_request(priv_dev, priv_ep);
+		}
+	}
+
+	cdns3_allow_enable_l1(priv_dev, 1);
+}
+
+/**
+ * cdns3_trb_handled - check whether trb has been handled by DMA
+ *
+ * @priv_ep: extended endpoint object.
+ * @priv_req: request object for checking
+ *
+ * Endpoint must be selected before invoking this function.
+ *
+ * Returns false if request has not been handled by DMA, else returns true.
+ *
+ * SR - start ring
+ * ER -  end ring
+ * DQ = priv_ep->dequeue - dequeue position
+ * EQ = priv_ep->enqueue -  enqueue position
+ * ST = priv_req->start_trb - index of first TRB in transfer ring
+ * ET = priv_req->end_trb - index of last TRB in transfer ring
+ * CI = current_index - index of processed TRB by DMA.
+ *
+ * As first step, we check if the TRB between the ST and ET.
+ * Then, we check if cycle bit for index priv_ep->dequeue
+ * is correct.
+ *
+ * some rules:
+ * 1. priv_ep->dequeue never equals to current_index.
+ * 2  priv_ep->enqueue never exceed priv_ep->dequeue
+ * 3. exception: priv_ep->enqueue == priv_ep->dequeue
+ *    and priv_ep->free_trbs is zero.
+ *    This case indicate that TR is full.
+ *
+ * At below two cases, the request have been handled.
+ * Case 1 - priv_ep->dequeue < current_index
+ *      SR ... EQ ... DQ ... CI ... ER
+ *      SR ... DQ ... CI ... EQ ... ER
+ *
+ * Case 2 - priv_ep->dequeue > current_index
+ * This situation takes place when CI go through the LINK TRB at the end of
+ * transfer ring.
+ *      SR ... CI ... EQ ... DQ ... ER
+ */
+static bool cdns3_trb_handled(struct cdns3_endpoint *priv_ep,
+				  struct cdns3_request *priv_req)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_trb *trb;
+	int current_index = 0;
+	int handled = 0;
+	int doorbell;
+
+	current_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+	doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+	/* current trb doesn't belong to this request */
+	if (priv_req->start_trb < priv_req->end_trb) {
+		if (priv_ep->dequeue > priv_req->end_trb)
+			goto finish;
+
+		if (priv_ep->dequeue < priv_req->start_trb)
+			goto finish;
+	}
+
+	if ((priv_req->start_trb > priv_req->end_trb) &&
+		(priv_ep->dequeue > priv_req->end_trb) &&
+		(priv_ep->dequeue < priv_req->start_trb))
+		goto finish;
+
+	if ((priv_req->start_trb == priv_req->end_trb) &&
+		(priv_ep->dequeue != priv_req->end_trb))
+		goto finish;
+
+	trb = &priv_ep->trb_pool[priv_ep->dequeue];
+
+	if ((le32_to_cpu(trb->control) & TRB_CYCLE) != priv_ep->ccs)
+		goto finish;
+
+	if (doorbell == 1 && current_index == priv_ep->dequeue)
+		goto finish;
+
+	/* The corner case for TRBS_PER_SEGMENT equal 2). */
+	if (TRBS_PER_SEGMENT == 2 && priv_ep->type != USB_ENDPOINT_XFER_ISOC) {
+		handled = 1;
+		goto finish;
+	}
+
+	if (priv_ep->enqueue == priv_ep->dequeue &&
+	    priv_ep->free_trbs == 0) {
+		handled = 1;
+	} else if (priv_ep->dequeue < current_index) {
+		if ((current_index == (priv_ep->num_trbs - 1)) &&
+		    !priv_ep->dequeue)
+			goto finish;
+
+		handled = 1;
+	} else if (priv_ep->dequeue  > current_index) {
+			handled = 1;
+	}
+
+finish:
+	trace_cdns3_request_handled(priv_req, current_index, handled);
+
+	return handled;
+}
+
+static void cdns3_transfer_completed(struct cdns3_device *priv_dev,
+				     struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_request *priv_req;
+	struct usb_request *request;
+	struct cdns3_trb *trb;
+	bool request_handled = false;
+	bool transfer_end = false;
+
+	while (!list_empty(&priv_ep->pending_req_list)) {
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+		priv_req = to_cdns3_request(request);
+
+		trb = priv_ep->trb_pool + priv_ep->dequeue;
+
+		/* The TRB was changed as link TRB, and the request was handled at ep_dequeue */
+		while (TRB_FIELD_TO_TYPE(le32_to_cpu(trb->control)) == TRB_LINK) {
+			trace_cdns3_complete_trb(priv_ep, trb);
+			cdns3_ep_inc_deq(priv_ep);
+			trb = priv_ep->trb_pool + priv_ep->dequeue;
+		}
+
+		if (!request->stream_id) {
+			/* Re-select endpoint. It could be changed by other CPU
+			 * during handling usb_gadget_giveback_request.
+			 */
+			cdns3_select_ep(priv_dev, priv_ep->endpoint.address);
+
+			while (cdns3_trb_handled(priv_ep, priv_req)) {
+				priv_req->finished_trb++;
+				if (priv_req->finished_trb >= priv_req->num_of_trb)
+					request_handled = true;
+
+				trb = priv_ep->trb_pool + priv_ep->dequeue;
+				trace_cdns3_complete_trb(priv_ep, trb);
+
+				if (!transfer_end)
+					request->actual +=
+						TRB_LEN(le32_to_cpu(trb->length));
+
+				if (priv_req->num_of_trb > 1 &&
+					le32_to_cpu(trb->control) & TRB_SMM &&
+					le32_to_cpu(trb->control) & TRB_CHAIN)
+					transfer_end = true;
+
+				cdns3_ep_inc_deq(priv_ep);
+			}
+
+			if (request_handled) {
+				cdns3_gadget_giveback(priv_ep, priv_req, 0);
+				request_handled = false;
+				transfer_end = false;
+			} else {
+				goto prepare_next_td;
+			}
+
+			if (priv_ep->type != USB_ENDPOINT_XFER_ISOC &&
+			    TRBS_PER_SEGMENT == 2)
+				break;
+		} else {
+			/* Re-select endpoint. It could be changed by other CPU
+			 * during handling usb_gadget_giveback_request.
+			 */
+			cdns3_select_ep(priv_dev, priv_ep->endpoint.address);
+
+			trb = priv_ep->trb_pool;
+			trace_cdns3_complete_trb(priv_ep, trb);
+
+			if (trb != priv_req->trb)
+				dev_warn(priv_dev->dev,
+					 "request_trb=0x%p, queue_trb=0x%p\n",
+					 priv_req->trb, trb);
+
+			request->actual += TRB_LEN(le32_to_cpu(trb->length));
+
+			if (!request->num_sgs ||
+			    (request->num_sgs == (priv_ep->stream_sg_idx + 1))) {
+				priv_ep->stream_sg_idx = 0;
+				cdns3_gadget_giveback(priv_ep, priv_req, 0);
+			} else {
+				priv_ep->stream_sg_idx++;
+				cdns3_ep_run_stream_transfer(priv_ep, request);
+			}
+			break;
+		}
+	}
+	priv_ep->flags &= ~EP_PENDING_REQUEST;
+
+prepare_next_td:
+	if (!(priv_ep->flags & EP_STALLED) &&
+	    !(priv_ep->flags & EP_STALL_PENDING))
+		cdns3_start_all_request(priv_dev, priv_ep);
+}
+
+void cdns3_rearm_transfer(struct cdns3_endpoint *priv_ep, u8 rearm)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	cdns3_wa1_restore_cycle_bit(priv_ep);
+
+	if (rearm) {
+		trace_cdns3_ring(priv_ep);
+
+		/* Cycle Bit must be updated before arming DMA. */
+		wmb();
+		writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+
+		__cdns3_gadget_wakeup(priv_dev);
+
+		trace_cdns3_doorbell_epx(priv_ep->name,
+					 readl(&priv_dev->regs->ep_traddr));
+	}
+}
+
+static void cdns3_reprogram_tdl(struct cdns3_endpoint *priv_ep)
+{
+	u16 tdl = priv_ep->pending_tdl;
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	if (tdl > EP_CMD_TDL_MAX) {
+		tdl = EP_CMD_TDL_MAX;
+		priv_ep->pending_tdl -= EP_CMD_TDL_MAX;
+	} else {
+		priv_ep->pending_tdl = 0;
+	}
+
+	writel(EP_CMD_TDL_SET(tdl) | EP_CMD_STDL, &priv_dev->regs->ep_cmd);
+}
+
+/**
+ * cdns3_check_ep_interrupt_proceed - Processes interrupt related to endpoint
+ * @priv_ep: endpoint object
+ *
+ * Returns 0
+ */
+static int cdns3_check_ep_interrupt_proceed(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	u32 ep_sts_reg;
+	struct usb_request *deferred_request;
+	struct usb_request *pending_request;
+	u32 tdl = 0;
+
+	cdns3_select_ep(priv_dev, priv_ep->endpoint.address);
+
+	trace_cdns3_epx_irq(priv_dev, priv_ep);
+
+	ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+	writel(ep_sts_reg, &priv_dev->regs->ep_sts);
+
+	if ((ep_sts_reg & EP_STS_PRIME) && priv_ep->use_streams) {
+		bool dbusy = !!(ep_sts_reg & EP_STS_DBUSY);
+
+		tdl = cdns3_get_tdl(priv_dev);
+
+		/*
+		 * Continue the previous transfer:
+		 * There is some racing between ERDY and PRIME. The device send
+		 * ERDY and almost in the same time Host send PRIME. It cause
+		 * that host ignore the ERDY packet and driver has to send it
+		 * again.
+		 */
+		if (tdl && (dbusy || !EP_STS_BUFFEMPTY(ep_sts_reg) ||
+		    EP_STS_HOSTPP(ep_sts_reg))) {
+			writel(EP_CMD_ERDY |
+			       EP_CMD_ERDY_SID(priv_ep->last_stream_id),
+			       &priv_dev->regs->ep_cmd);
+			ep_sts_reg &= ~(EP_STS_MD_EXIT | EP_STS_IOC);
+		} else {
+			priv_ep->prime_flag = true;
+
+			pending_request = cdns3_next_request(&priv_ep->pending_req_list);
+			deferred_request = cdns3_next_request(&priv_ep->deferred_req_list);
+
+			if (deferred_request && !pending_request) {
+				cdns3_start_all_request(priv_dev, priv_ep);
+			}
+		}
+	}
+
+	if (ep_sts_reg & EP_STS_TRBERR) {
+		if (priv_ep->flags & EP_STALL_PENDING &&
+		    !(ep_sts_reg & EP_STS_DESCMIS &&
+		    priv_dev->dev_ver < DEV_VER_V2)) {
+			cdns3_ep_stall_flush(priv_ep);
+		}
+
+		/*
+		 * For isochronous transfer driver completes request on
+		 * IOC or on TRBERR. IOC appears only when device receive
+		 * OUT data packet. If host disable stream or lost some packet
+		 * then the only way to finish all queued transfer is to do it
+		 * on TRBERR event.
+		 */
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC &&
+		    !priv_ep->wa1_set) {
+			if (!priv_ep->dir) {
+				u32 ep_cfg = readl(&priv_dev->regs->ep_cfg);
+
+				ep_cfg &= ~EP_CFG_ENABLE;
+				writel(ep_cfg, &priv_dev->regs->ep_cfg);
+				priv_ep->flags &= ~EP_QUIRK_ISO_OUT_EN;
+				priv_ep->flags |= EP_UPDATE_EP_TRBADDR;
+			}
+			cdns3_transfer_completed(priv_dev, priv_ep);
+		} else if (!(priv_ep->flags & EP_STALLED) &&
+			  !(priv_ep->flags & EP_STALL_PENDING)) {
+			if (priv_ep->flags & EP_DEFERRED_DRDY) {
+				priv_ep->flags &= ~EP_DEFERRED_DRDY;
+				cdns3_start_all_request(priv_dev, priv_ep);
+			} else {
+				cdns3_rearm_transfer(priv_ep,
+						     priv_ep->wa1_set);
+			}
+		}
+	}
+
+	if ((ep_sts_reg & EP_STS_IOC) || (ep_sts_reg & EP_STS_ISP) ||
+	    (ep_sts_reg & EP_STS_IOT)) {
+		if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+			if (ep_sts_reg & EP_STS_ISP)
+				priv_ep->flags |= EP_QUIRK_END_TRANSFER;
+			else
+				priv_ep->flags &= ~EP_QUIRK_END_TRANSFER;
+		}
+
+		if (!priv_ep->use_streams) {
+			if ((ep_sts_reg & EP_STS_IOC) ||
+			    (ep_sts_reg & EP_STS_ISP)) {
+				cdns3_transfer_completed(priv_dev, priv_ep);
+			} else if ((priv_ep->flags & EP_TDLCHK_EN) &
+				   priv_ep->pending_tdl) {
+				/* handle IOT with pending tdl */
+				cdns3_reprogram_tdl(priv_ep);
+			}
+		} else if (priv_ep->dir == USB_DIR_OUT) {
+			priv_ep->ep_sts_pending |= ep_sts_reg;
+		} else if (ep_sts_reg & EP_STS_IOT) {
+			cdns3_transfer_completed(priv_dev, priv_ep);
+		}
+	}
+
+	/*
+	 * MD_EXIT interrupt sets when stream capable endpoint exits
+	 * from MOVE DATA state of Bulk IN/OUT stream protocol state machine
+	 */
+	if (priv_ep->dir == USB_DIR_OUT && (ep_sts_reg & EP_STS_MD_EXIT) &&
+	    (priv_ep->ep_sts_pending & EP_STS_IOT) && priv_ep->use_streams) {
+		priv_ep->ep_sts_pending = 0;
+		cdns3_transfer_completed(priv_dev, priv_ep);
+	}
+
+	/*
+	 * WA2: this condition should only be meet when
+	 * priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET or
+	 * priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN.
+	 * In other cases this interrupt will be disabled.
+	 */
+	if (ep_sts_reg & EP_STS_DESCMIS && priv_dev->dev_ver < DEV_VER_V2 &&
+	    !(priv_ep->flags & EP_STALLED))
+		cdns3_wa2_descmissing_packet(priv_ep);
+
+	return 0;
+}
+
+static void cdns3_disconnect_gadget(struct cdns3_device *priv_dev)
+{
+	if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect)
+		priv_dev->gadget_driver->disconnect(&priv_dev->gadget);
+}
+
+/**
+ * cdns3_check_usb_interrupt_proceed - Processes interrupt related to device
+ * @priv_dev: extended gadget object
+ * @usb_ists: bitmap representation of device's reported interrupts
+ * (usb_ists register value)
+ */
+static void cdns3_check_usb_interrupt_proceed(struct cdns3_device *priv_dev,
+					      u32 usb_ists)
+__must_hold(&priv_dev->lock)
+{
+	int speed = 0;
+
+	trace_cdns3_usb_irq(priv_dev, usb_ists);
+	if (usb_ists & USB_ISTS_L1ENTI) {
+		/*
+		 * WORKAROUND: CDNS3 controller has issue with hardware resuming
+		 * from L1. To fix it, if any DMA transfer is pending driver
+		 * must starts driving resume signal immediately.
+		 */
+		if (readl(&priv_dev->regs->drbl))
+			__cdns3_gadget_wakeup(priv_dev);
+	}
+
+	/* Connection detected */
+	if (usb_ists & (USB_ISTS_CON2I | USB_ISTS_CONI)) {
+		speed = cdns3_get_speed(priv_dev);
+		priv_dev->gadget.speed = speed;
+		usb_gadget_set_state(&priv_dev->gadget, USB_STATE_POWERED);
+		cdns3_ep0_config(priv_dev);
+	}
+
+	/* Disconnection detected */
+	if (usb_ists & (USB_ISTS_DIS2I | USB_ISTS_DISI)) {
+		spin_unlock(&priv_dev->lock);
+		cdns3_disconnect_gadget(priv_dev);
+		spin_lock(&priv_dev->lock);
+		priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+		usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
+		cdns3_hw_reset_eps_config(priv_dev);
+	}
+
+	if (usb_ists & (USB_ISTS_L2ENTI | USB_ISTS_U3ENTI)) {
+		if (priv_dev->gadget_driver &&
+		    priv_dev->gadget_driver->suspend) {
+			spin_unlock(&priv_dev->lock);
+			priv_dev->gadget_driver->suspend(&priv_dev->gadget);
+			spin_lock(&priv_dev->lock);
+		}
+	}
+
+	if (usb_ists & (USB_ISTS_L2EXTI | USB_ISTS_U3EXTI)) {
+		if (priv_dev->gadget_driver &&
+		    priv_dev->gadget_driver->resume) {
+			spin_unlock(&priv_dev->lock);
+			priv_dev->gadget_driver->resume(&priv_dev->gadget);
+			spin_lock(&priv_dev->lock);
+		}
+	}
+
+	/* reset*/
+	if (usb_ists & (USB_ISTS_UWRESI | USB_ISTS_UHRESI | USB_ISTS_U2RESI)) {
+		if (priv_dev->gadget_driver) {
+			spin_unlock(&priv_dev->lock);
+			usb_gadget_udc_reset(&priv_dev->gadget,
+					     priv_dev->gadget_driver);
+			spin_lock(&priv_dev->lock);
+
+			/*read again to check the actual speed*/
+			speed = cdns3_get_speed(priv_dev);
+			priv_dev->gadget.speed = speed;
+			cdns3_hw_reset_eps_config(priv_dev);
+			cdns3_ep0_config(priv_dev);
+		}
+	}
+}
+
+/**
+ * cdns3_device_irq_handler- interrupt handler for device part of controller
+ *
+ * @irq: irq number for cdns3 core device
+ * @data: structure of cdns3
+ *
+ * Returns IRQ_HANDLED or IRQ_NONE
+ */
+static irqreturn_t cdns3_device_irq_handler(int irq, void *data)
+{
+	struct cdns3_device *priv_dev = data;
+	struct cdns3 *cdns = dev_get_drvdata(priv_dev->dev);
+	irqreturn_t ret = IRQ_NONE;
+	u32 reg;
+
+	if (cdns->in_lpm)
+		return ret;
+
+	/* check USB device interrupt */
+	reg = readl(&priv_dev->regs->usb_ists);
+	if (reg) {
+		/* After masking interrupts the new interrupts won't be
+		 * reported in usb_ists/ep_ists. In order to not lose some
+		 * of them driver disables only detected interrupts.
+		 * They will be enabled ASAP after clearing source of
+		 * interrupt. This an unusual behavior only applies to
+		 * usb_ists register.
+		 */
+		reg = ~reg & readl(&priv_dev->regs->usb_ien);
+		/* mask deferred interrupt. */
+		writel(reg, &priv_dev->regs->usb_ien);
+		ret = IRQ_WAKE_THREAD;
+	}
+
+	/* check endpoint interrupt */
+	reg = readl(&priv_dev->regs->ep_ists);
+	if (reg) {
+		writel(0, &priv_dev->regs->ep_ien);
+		ret = IRQ_WAKE_THREAD;
+	}
+
+	return ret;
+}
+
+/**
+ * cdns3_device_thread_irq_handler- interrupt handler for device part
+ * of controller
+ *
+ * @irq: irq number for cdns3 core device
+ * @data: structure of cdns3
+ *
+ * Returns IRQ_HANDLED or IRQ_NONE
+ */
+static irqreturn_t cdns3_device_thread_irq_handler(int irq, void *data)
+{
+	struct cdns3_device *priv_dev = data;
+	irqreturn_t ret = IRQ_NONE;
+	unsigned long flags;
+	unsigned int bit;
+	unsigned long reg;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	reg = readl(&priv_dev->regs->usb_ists);
+	if (reg) {
+		writel(reg, &priv_dev->regs->usb_ists);
+		writel(USB_IEN_INIT, &priv_dev->regs->usb_ien);
+		cdns3_check_usb_interrupt_proceed(priv_dev, reg);
+		ret = IRQ_HANDLED;
+	}
+
+	reg = readl(&priv_dev->regs->ep_ists);
+
+	/* handle default endpoint OUT */
+	if (reg & EP_ISTS_EP_OUT0) {
+		cdns3_check_ep0_interrupt_proceed(priv_dev, USB_DIR_OUT);
+		ret = IRQ_HANDLED;
+	}
+
+	/* handle default endpoint IN */
+	if (reg & EP_ISTS_EP_IN0) {
+		cdns3_check_ep0_interrupt_proceed(priv_dev, USB_DIR_IN);
+		ret = IRQ_HANDLED;
+	}
+
+	/* check if interrupt from non default endpoint, if no exit */
+	reg &= ~(EP_ISTS_EP_OUT0 | EP_ISTS_EP_IN0);
+	if (!reg)
+		goto irqend;
+
+	for_each_set_bit(bit, &reg,
+			 sizeof(u32) * BITS_PER_BYTE) {
+		cdns3_check_ep_interrupt_proceed(priv_dev->eps[bit]);
+		ret = IRQ_HANDLED;
+	}
+
+	if (priv_dev->dev_ver < DEV_VER_V2 && priv_dev->using_streams)
+		cdns3_wa2_check_outq_status(priv_dev);
+
+irqend:
+	writel(~0, &priv_dev->regs->ep_ien);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_ep_onchip_buffer_reserve - Try to reserve onchip buf for EP
+ *
+ * The real reservation will occur during write to EP_CFG register,
+ * this function is used to check if the 'size' reservation is allowed.
+ *
+ * @priv_dev: extended gadget object
+ * @size: the size (KB) for EP would like to allocate
+ * @is_in: endpoint direction
+ *
+ * Return 0 if the required size can met or negative value on failure
+ */
+static int cdns3_ep_onchip_buffer_reserve(struct cdns3_device *priv_dev,
+					  int size, int is_in)
+{
+	int remained;
+
+	/* 2KB are reserved for EP0*/
+	remained = priv_dev->onchip_buffers - priv_dev->onchip_used_size - 2;
+
+	if (is_in) {
+		if (remained < size)
+			return -EPERM;
+
+		priv_dev->onchip_used_size += size;
+	} else {
+		int required;
+
+		/**
+		 *  ALL OUT EPs are shared the same chunk onchip memory, so
+		 * driver checks if it already has assigned enough buffers
+		 */
+		if (priv_dev->out_mem_is_allocated >= size)
+			return 0;
+
+		required = size - priv_dev->out_mem_is_allocated;
+
+		if (required > remained)
+			return -EPERM;
+
+		priv_dev->out_mem_is_allocated += required;
+		priv_dev->onchip_used_size += required;
+	}
+
+	return 0;
+}
+
+static void cdns3_configure_dmult(struct cdns3_device *priv_dev,
+				  struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+
+	/* For dev_ver > DEV_VER_V2 DMULT is configured per endpoint */
+	if (priv_dev->dev_ver <= DEV_VER_V2)
+		writel(USB_CONF_DMULT, &regs->usb_conf);
+
+	if (priv_dev->dev_ver == DEV_VER_V2)
+		writel(USB_CONF2_EN_TDL_TRB, &regs->usb_conf2);
+
+	if (priv_dev->dev_ver >= DEV_VER_V3 && priv_ep) {
+		u32 mask;
+
+		if (priv_ep->dir)
+			mask = BIT(priv_ep->num + 16);
+		else
+			mask = BIT(priv_ep->num);
+
+		if (priv_ep->type != USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir) {
+			cdns3_set_register_bit(&regs->tdl_from_trb, mask);
+			cdns3_set_register_bit(&regs->tdl_beh, mask);
+			cdns3_set_register_bit(&regs->tdl_beh2, mask);
+			cdns3_set_register_bit(&regs->dma_adv_td, mask);
+		}
+
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC && !priv_ep->dir)
+			cdns3_set_register_bit(&regs->tdl_from_trb, mask);
+
+		cdns3_set_register_bit(&regs->dtrans, mask);
+	}
+}
+
+/**
+ * cdns3_ep_config Configure hardware endpoint
+ * @priv_ep: extended endpoint object
+ * @enable: set EP_CFG_ENABLE bit in ep_cfg register.
+ */
+int cdns3_ep_config(struct cdns3_endpoint *priv_ep, bool enable)
+{
+	bool is_iso_ep = (priv_ep->type == USB_ENDPOINT_XFER_ISOC);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	u32 bEndpointAddress = priv_ep->num | priv_ep->dir;
+	u32 max_packet_size = 0;
+	u8 maxburst = 0;
+	u32 ep_cfg = 0;
+	u8 buffering;
+	u8 mult = 0;
+	int ret;
+
+	buffering = priv_dev->ep_buf_size - 1;
+
+	cdns3_configure_dmult(priv_dev, priv_ep);
+
+	switch (priv_ep->type) {
+	case USB_ENDPOINT_XFER_INT:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_INT);
+
+		if (priv_dev->dev_ver >= DEV_VER_V2 && !priv_ep->dir)
+			ep_cfg |= EP_CFG_TDL_CHK;
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_BULK);
+
+		if (priv_dev->dev_ver >= DEV_VER_V2 && !priv_ep->dir)
+			ep_cfg |= EP_CFG_TDL_CHK;
+		break;
+	default:
+		ep_cfg = EP_CFG_EPTYPE(USB_ENDPOINT_XFER_ISOC);
+		mult = priv_dev->ep_iso_burst - 1;
+		buffering = mult + 1;
+	}
+
+	switch (priv_dev->gadget.speed) {
+	case USB_SPEED_FULL:
+		max_packet_size = is_iso_ep ? 1023 : 64;
+		break;
+	case USB_SPEED_HIGH:
+		max_packet_size = is_iso_ep ? 1024 : 512;
+		break;
+	case USB_SPEED_SUPER:
+		/* It's limitation that driver assumes in driver. */
+		mult = 0;
+		max_packet_size = 1024;
+		if (priv_ep->type == USB_ENDPOINT_XFER_ISOC) {
+			maxburst = priv_dev->ep_iso_burst - 1;
+			buffering = (mult + 1) *
+				    (maxburst + 1);
+
+			if (priv_ep->interval > 1)
+				buffering++;
+		} else {
+			maxburst = priv_dev->ep_buf_size - 1;
+		}
+		break;
+	default:
+		/* all other speed are not supported */
+		return -EINVAL;
+	}
+
+	if (max_packet_size == 1024)
+		priv_ep->trb_burst_size = 128;
+	else if (max_packet_size >= 512)
+		priv_ep->trb_burst_size = 64;
+	else
+		priv_ep->trb_burst_size = 16;
+
+	/*
+	 * In versions preceding DEV_VER_V2, for example, iMX8QM, there exit the bugs
+	 * in the DMA. These bugs occur when the trb_burst_size exceeds 16 and the
+	 * address is not aligned to 128 Bytes (which is a product of the 64-bit AXI
+	 * and AXI maximum burst length of 16 or 0xF+1, dma_axi_ctrl0[3:0]). This
+	 * results in data corruption when it crosses the 4K border. The corruption
+	 * specifically occurs from the position (4K - (address & 0x7F)) to 4K.
+	 *
+	 * So force trb_burst_size to 16 at such platform.
+	 */
+	if (priv_dev->dev_ver < DEV_VER_V2)
+		priv_ep->trb_burst_size = 16;
+
+	mult = min_t(u8, mult, EP_CFG_MULT_MAX);
+	buffering = min_t(u8, buffering, EP_CFG_BUFFERING_MAX);
+	maxburst = min_t(u8, maxburst, EP_CFG_MAXBURST_MAX);
+
+	/* onchip buffer is only allocated before configuration */
+	if (!priv_dev->hw_configured_flag) {
+		ret = cdns3_ep_onchip_buffer_reserve(priv_dev, buffering + 1,
+						     !!priv_ep->dir);
+		if (ret) {
+			dev_err(priv_dev->dev, "onchip mem is full, ep is invalid\n");
+			return ret;
+		}
+	}
+
+	if (enable)
+		ep_cfg |= EP_CFG_ENABLE;
+
+	if (priv_ep->use_streams && priv_dev->gadget.speed >= USB_SPEED_SUPER) {
+		if (priv_dev->dev_ver >= DEV_VER_V3) {
+			u32 mask = BIT(priv_ep->num + (priv_ep->dir ? 16 : 0));
+
+			/*
+			 * Stream capable endpoints are handled by using ep_tdl
+			 * register. Other endpoints use TDL from TRB feature.
+			 */
+			cdns3_clear_register_bit(&priv_dev->regs->tdl_from_trb,
+						 mask);
+		}
+
+		/*  Enable Stream Bit TDL chk and SID chk */
+		ep_cfg |=  EP_CFG_STREAM_EN | EP_CFG_TDL_CHK | EP_CFG_SID_CHK;
+	}
+
+	ep_cfg |= EP_CFG_MAXPKTSIZE(max_packet_size) |
+		  EP_CFG_MULT(mult) |
+		  EP_CFG_BUFFERING(buffering) |
+		  EP_CFG_MAXBURST(maxburst);
+
+	cdns3_select_ep(priv_dev, bEndpointAddress);
+	writel(ep_cfg, &priv_dev->regs->ep_cfg);
+	priv_ep->flags |= EP_CONFIGURED;
+
+	dev_dbg(priv_dev->dev, "Configure %s: with val %08x\n",
+		priv_ep->name, ep_cfg);
+
+	return 0;
+}
+
+/* Find correct direction for HW endpoint according to description */
+static int cdns3_ep_dir_is_correct(struct usb_endpoint_descriptor *desc,
+				   struct cdns3_endpoint *priv_ep)
+{
+	return (priv_ep->endpoint.caps.dir_in && usb_endpoint_dir_in(desc)) ||
+	       (priv_ep->endpoint.caps.dir_out && usb_endpoint_dir_out(desc));
+}
+
+static struct
+cdns3_endpoint *cdns3_find_available_ep(struct cdns3_device *priv_dev,
+					struct usb_endpoint_descriptor *desc)
+{
+	struct usb_ep *ep;
+	struct cdns3_endpoint *priv_ep;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		unsigned long num;
+		int ret;
+		/* ep name pattern likes epXin or epXout */
+		char c[2] = {ep->name[2], '\0'};
+
+		ret = kstrtoul(c, 10, &num);
+		if (ret)
+			return ERR_PTR(ret);
+
+		priv_ep = ep_to_cdns3_ep(ep);
+		if (cdns3_ep_dir_is_correct(desc, priv_ep)) {
+			if (!(priv_ep->flags & EP_CLAIMED)) {
+				priv_ep->num  = num;
+				return priv_ep;
+			}
+		}
+	}
+
+	return ERR_PTR(-ENOENT);
+}
+
+/*
+ *  Cadence IP has one limitation that all endpoints must be configured
+ * (Type & MaxPacketSize) before setting configuration through hardware
+ * register, it means we can't change endpoints configuration after
+ * set_configuration.
+ *
+ * This function set EP_CLAIMED flag which is added when the gadget driver
+ * uses usb_ep_autoconfig to configure specific endpoint;
+ * When the udc driver receives set_configurion request,
+ * it goes through all claimed endpoints, and configure all endpoints
+ * accordingly.
+ *
+ * At usb_ep_ops.enable/disable, we only enable and disable endpoint through
+ * ep_cfg register which can be changed after set_configuration, and do
+ * some software operation accordingly.
+ */
+static struct
+usb_ep *cdns3_gadget_match_ep(struct usb_gadget *gadget,
+			      struct usb_endpoint_descriptor *desc,
+			      struct usb_ss_ep_comp_descriptor *comp_desc)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct cdns3_endpoint *priv_ep;
+	unsigned long flags;
+
+	priv_ep = cdns3_find_available_ep(priv_dev, desc);
+	if (IS_ERR(priv_ep)) {
+		dev_err(priv_dev->dev, "no available ep\n");
+		return NULL;
+	}
+
+	dev_dbg(priv_dev->dev, "match endpoint: %s\n", priv_ep->name);
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_ep->endpoint.desc = desc;
+	priv_ep->dir  = usb_endpoint_dir_in(desc) ? USB_DIR_IN : USB_DIR_OUT;
+	priv_ep->type = usb_endpoint_type(desc);
+	priv_ep->flags |= EP_CLAIMED;
+	priv_ep->interval = desc->bInterval ? BIT(desc->bInterval - 1) : 0;
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return &priv_ep->endpoint;
+}
+
+/**
+ * cdns3_gadget_ep_alloc_request Allocates request
+ * @ep: endpoint object associated with request
+ * @gfp_flags: gfp flags
+ *
+ * Returns allocated request address, NULL on allocation error
+ */
+struct usb_request *cdns3_gadget_ep_alloc_request(struct usb_ep *ep,
+						  gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_request *priv_req;
+
+	priv_req = kzalloc(sizeof(*priv_req), gfp_flags);
+	if (!priv_req)
+		return NULL;
+
+	priv_req->priv_ep = priv_ep;
+
+	trace_cdns3_alloc_request(priv_req);
+	return &priv_req->request;
+}
+
+/**
+ * cdns3_gadget_ep_free_request Free memory occupied by request
+ * @ep: endpoint object associated with request
+ * @request: request to free memory
+ */
+void cdns3_gadget_ep_free_request(struct usb_ep *ep,
+				  struct usb_request *request)
+{
+	struct cdns3_request *priv_req = to_cdns3_request(request);
+
+	if (priv_req->aligned_buf)
+		priv_req->aligned_buf->in_use = 0;
+
+	trace_cdns3_free_request(priv_req);
+	kfree(priv_req);
+}
+
+/**
+ * cdns3_gadget_ep_enable Enable endpoint
+ * @ep: endpoint object
+ * @desc: endpoint descriptor
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep_enable(struct usb_ep *ep,
+				  const struct usb_endpoint_descriptor *desc)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_device *priv_dev;
+	const struct usb_ss_ep_comp_descriptor *comp_desc;
+	u32 reg = EP_STS_EN_TRBERREN;
+	u32 bEndpointAddress;
+	unsigned long flags;
+	int enable = 1;
+	int ret = 0;
+	int val;
+
+	if (!ep) {
+		pr_debug("usbss: ep not configured?\n");
+		return -EINVAL;
+	}
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+	comp_desc = priv_ep->endpoint.comp_desc;
+
+	if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
+		dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
+		return -EINVAL;
+	}
+
+	if (!desc->wMaxPacketSize) {
+		dev_err(priv_dev->dev, "usbss: missing wMaxPacketSize\n");
+		return -EINVAL;
+	}
+
+	if (dev_WARN_ONCE(priv_dev->dev, priv_ep->flags & EP_ENABLED,
+			  "%s is already enabled\n", priv_ep->name))
+		return 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	priv_ep->endpoint.desc = desc;
+	priv_ep->type = usb_endpoint_type(desc);
+	priv_ep->interval = desc->bInterval ? BIT(desc->bInterval - 1) : 0;
+
+	if (priv_ep->interval > ISO_MAX_INTERVAL &&
+	    priv_ep->type == USB_ENDPOINT_XFER_ISOC) {
+		dev_err(priv_dev->dev, "Driver is limited to %d period\n",
+			ISO_MAX_INTERVAL);
+
+		ret =  -EINVAL;
+		goto exit;
+	}
+
+	bEndpointAddress = priv_ep->num | priv_ep->dir;
+	cdns3_select_ep(priv_dev, bEndpointAddress);
+
+	/*
+	 * For some versions of controller at some point during ISO OUT traffic
+	 * DMA reads Transfer Ring for the EP which has never got doorbell.
+	 * This issue was detected only on simulation, but to avoid this issue
+	 * driver add protection against it. To fix it driver enable ISO OUT
+	 * endpoint before setting DRBL. This special treatment of ISO OUT
+	 * endpoints are recommended by controller specification.
+	 */
+	if (priv_ep->type == USB_ENDPOINT_XFER_ISOC  && !priv_ep->dir)
+		enable = 0;
+
+	if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
+		/*
+		 * Enable stream support (SS mode) related interrupts
+		 * in EP_STS_EN Register
+		 */
+		if (priv_dev->gadget.speed >= USB_SPEED_SUPER) {
+			reg |= EP_STS_EN_IOTEN | EP_STS_EN_PRIMEEEN |
+				EP_STS_EN_SIDERREN | EP_STS_EN_MD_EXITEN |
+				EP_STS_EN_STREAMREN;
+			priv_ep->use_streams = true;
+			ret = cdns3_ep_config(priv_ep, enable);
+			priv_dev->using_streams |= true;
+		}
+	} else {
+		ret = cdns3_ep_config(priv_ep, enable);
+	}
+
+	if (ret)
+		goto exit;
+
+	ret = cdns3_allocate_trb_pool(priv_ep);
+	if (ret)
+		goto exit;
+
+	bEndpointAddress = priv_ep->num | priv_ep->dir;
+	cdns3_select_ep(priv_dev, bEndpointAddress);
+
+	trace_cdns3_gadget_ep_enable(priv_ep);
+
+	writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	ret = readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+					!(val & (EP_CMD_CSTALL | EP_CMD_EPRST)),
+					1, 1000);
+
+	if (unlikely(ret)) {
+		cdns3_free_trb_pool(priv_ep);
+		ret =  -EINVAL;
+		goto exit;
+	}
+
+	/* enable interrupt for selected endpoint */
+	cdns3_set_register_bit(&priv_dev->regs->ep_ien,
+			       BIT(cdns3_ep_addr_to_index(bEndpointAddress)));
+
+	if (priv_dev->dev_ver < DEV_VER_V2)
+		cdns3_wa2_enable_detection(priv_dev, priv_ep, reg);
+
+	writel(reg, &priv_dev->regs->ep_sts_en);
+
+	ep->desc = desc;
+	priv_ep->flags &= ~(EP_PENDING_REQUEST | EP_STALLED | EP_STALL_PENDING |
+			    EP_QUIRK_ISO_OUT_EN | EP_QUIRK_EXTRA_BUF_EN);
+	priv_ep->flags |= EP_ENABLED | EP_UPDATE_EP_TRBADDR;
+	priv_ep->wa1_set = 0;
+	priv_ep->enqueue = 0;
+	priv_ep->dequeue = 0;
+	reg = readl(&priv_dev->regs->ep_sts);
+	priv_ep->pcs = !!EP_STS_CCS(reg);
+	priv_ep->ccs = !!EP_STS_CCS(reg);
+	/* one TRB is reserved for link TRB used in DMULT mode*/
+	priv_ep->free_trbs = priv_ep->num_trbs - 1;
+exit:
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_disable Disable endpoint
+ * @ep: endpoint object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_ep_disable(struct usb_ep *ep)
+{
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_request *priv_req;
+	struct cdns3_device *priv_dev;
+	struct usb_request *request;
+	unsigned long flags;
+	int ret = 0;
+	u32 ep_cfg;
+	int val;
+
+	if (!ep) {
+		pr_err("usbss: invalid parameters\n");
+		return -EINVAL;
+	}
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+
+	if (dev_WARN_ONCE(priv_dev->dev, !(priv_ep->flags & EP_ENABLED),
+			  "%s is already disabled\n", priv_ep->name))
+		return 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	trace_cdns3_gadget_ep_disable(priv_ep);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	ep_cfg = readl(&priv_dev->regs->ep_cfg);
+	ep_cfg &= ~EP_CFG_ENABLE;
+	writel(ep_cfg, &priv_dev->regs->ep_cfg);
+
+	/**
+	 * Driver needs some time before resetting endpoint.
+	 * It need waits for clearing DBUSY bit or for timeout expired.
+	 * 10us is enough time for controller to stop transfer.
+	 */
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_sts, val,
+				  !(val & EP_STS_DBUSY), 1, 10);
+	writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+				  !(val & (EP_CMD_CSTALL | EP_CMD_EPRST)),
+				  1, 1000);
+	if (unlikely(ret))
+		dev_err(priv_dev->dev, "Timeout: %s resetting failed.\n",
+			priv_ep->name);
+
+	while (!list_empty(&priv_ep->pending_req_list)) {
+		request = cdns3_next_request(&priv_ep->pending_req_list);
+
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
+				      -ESHUTDOWN);
+	}
+
+	while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+		priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+
+		kfree(priv_req->request.buf);
+		cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+					     &priv_req->request);
+		list_del_init(&priv_req->list);
+		--priv_ep->wa2_counter;
+	}
+
+	while (!list_empty(&priv_ep->deferred_req_list)) {
+		request = cdns3_next_request(&priv_ep->deferred_req_list);
+
+		cdns3_gadget_giveback(priv_ep, to_cdns3_request(request),
+				      -ESHUTDOWN);
+	}
+
+	priv_ep->descmis_req = NULL;
+
+	ep->desc = NULL;
+	priv_ep->flags &= ~EP_ENABLED;
+	priv_ep->use_streams = false;
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_queue Transfer data on endpoint
+ * @ep: endpoint object
+ * @request: request object
+ * @gfp_flags: gfp flags
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int __cdns3_gadget_ep_queue(struct usb_ep *ep,
+				   struct usb_request *request,
+				   gfp_t gfp_flags)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct cdns3_request *priv_req;
+	int ret = 0;
+
+	request->actual = 0;
+	request->status = -EINPROGRESS;
+	priv_req = to_cdns3_request(request);
+	trace_cdns3_ep_queue(priv_req);
+
+	if (priv_dev->dev_ver < DEV_VER_V2) {
+		ret = cdns3_wa2_gadget_ep_queue(priv_dev, priv_ep,
+						priv_req);
+
+		if (ret == EINPROGRESS)
+			return 0;
+	}
+
+	ret = cdns3_prepare_aligned_request_buf(priv_req);
+	if (ret < 0)
+		return ret;
+
+	ret = usb_gadget_map_request_by_dev(priv_dev->sysdev, request,
+					    usb_endpoint_dir_in(ep->desc));
+	if (ret)
+		return ret;
+
+	list_add_tail(&request->list, &priv_ep->deferred_req_list);
+
+	/*
+	 * For stream capable endpoint if prime irq flag is set then only start
+	 * request.
+	 * If hardware endpoint configuration has not been set yet then
+	 * just queue request in deferred list. Transfer will be started in
+	 * cdns3_set_hw_configuration.
+	 */
+	if (!request->stream_id) {
+		if (priv_dev->hw_configured_flag &&
+		    !(priv_ep->flags & EP_STALLED) &&
+		    !(priv_ep->flags & EP_STALL_PENDING))
+			cdns3_start_all_request(priv_dev, priv_ep);
+	} else {
+		if (priv_dev->hw_configured_flag && priv_ep->prime_flag)
+			cdns3_start_all_request(priv_dev, priv_ep);
+	}
+
+	return 0;
+}
+
+static int cdns3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
+				 gfp_t gfp_flags)
+{
+	struct usb_request *zlp_request;
+	struct cdns3_endpoint *priv_ep;
+	struct cdns3_device *priv_dev;
+	unsigned long flags;
+	int ret;
+
+	if (!request || !ep)
+		return -EINVAL;
+
+	priv_ep = ep_to_cdns3_ep(ep);
+	priv_dev = priv_ep->cdns3_dev;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	ret = __cdns3_gadget_ep_queue(ep, request, gfp_flags);
+
+	if (ret == 0 && request->zero && request->length &&
+	    (request->length % ep->maxpacket == 0)) {
+		struct cdns3_request *priv_req;
+
+		zlp_request = cdns3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
+		zlp_request->buf = priv_dev->zlp_buf;
+		zlp_request->length = 0;
+
+		priv_req = to_cdns3_request(zlp_request);
+		priv_req->flags |= REQUEST_ZLP;
+
+		dev_dbg(priv_dev->dev, "Queuing ZLP for endpoint: %s\n",
+			priv_ep->name);
+		ret = __cdns3_gadget_ep_queue(ep, zlp_request, gfp_flags);
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_dequeue Remove request from transfer queue
+ * @ep: endpoint object associated with request
+ * @request: request object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+int cdns3_gadget_ep_dequeue(struct usb_ep *ep,
+			    struct usb_request *request)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev;
+	struct usb_request *req, *req_temp;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *link_trb;
+	u8 req_on_hw_ring = 0;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!ep || !request || !ep->desc)
+		return -EINVAL;
+
+	priv_dev = priv_ep->cdns3_dev;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	priv_req = to_cdns3_request(request);
+
+	trace_cdns3_ep_dequeue(priv_req);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	list_for_each_entry_safe(req, req_temp, &priv_ep->pending_req_list,
+				 list) {
+		if (request == req) {
+			req_on_hw_ring = 1;
+			goto found;
+		}
+	}
+
+	list_for_each_entry_safe(req, req_temp, &priv_ep->deferred_req_list,
+				 list) {
+		if (request == req)
+			goto found;
+	}
+
+	goto not_found;
+
+found:
+	link_trb = priv_req->trb;
+
+	/* Update ring only if removed request is on pending_req_list list */
+	if (req_on_hw_ring && link_trb) {
+		link_trb->buffer = cpu_to_le32(TRB_BUFFER(priv_ep->trb_pool_dma +
+			((priv_req->end_trb + 1) * TRB_SIZE)));
+		link_trb->control = cpu_to_le32((le32_to_cpu(link_trb->control) & TRB_CYCLE) |
+				    TRB_TYPE(TRB_LINK) | TRB_CHAIN);
+
+		if (priv_ep->wa1_trb == priv_req->trb)
+			cdns3_wa1_restore_cycle_bit(priv_ep);
+	}
+
+	cdns3_gadget_giveback(priv_ep, priv_req, -ECONNRESET);
+
+not_found:
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+/**
+ * __cdns3_gadget_ep_set_halt Sets stall on selected endpoint
+ * Should be called after acquiring spin_lock and selecting ep
+ * @priv_ep: endpoint object to set stall on.
+ */
+void __cdns3_gadget_ep_set_halt(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+	trace_cdns3_halt(priv_ep, 1, 0);
+
+	if (!(priv_ep->flags & EP_STALLED)) {
+		u32 ep_sts_reg = readl(&priv_dev->regs->ep_sts);
+
+		if (!(ep_sts_reg & EP_STS_DBUSY))
+			cdns3_ep_stall_flush(priv_ep);
+		else
+			priv_ep->flags |= EP_STALL_PENDING;
+	}
+}
+
+/**
+ * __cdns3_gadget_ep_clear_halt Clears stall on selected endpoint
+ * Should be called after acquiring spin_lock and selecting ep
+ * @priv_ep: endpoint object to clear stall on
+ */
+int __cdns3_gadget_ep_clear_halt(struct cdns3_endpoint *priv_ep)
+{
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	struct usb_request *request;
+	struct cdns3_request *priv_req;
+	struct cdns3_trb *trb = NULL;
+	struct cdns3_trb trb_tmp;
+	int ret;
+	int val;
+
+	trace_cdns3_halt(priv_ep, 0, 0);
+
+	request = cdns3_next_request(&priv_ep->pending_req_list);
+	if (request) {
+		priv_req = to_cdns3_request(request);
+		trb = priv_req->trb;
+		if (trb) {
+			trb_tmp = *trb;
+			trb->control = trb->control ^ cpu_to_le32(TRB_CYCLE);
+		}
+	}
+
+	writel(EP_CMD_CSTALL | EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+
+	/* wait for EPRST cleared */
+	ret = readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+					!(val & EP_CMD_EPRST), 1, 100);
+	if (ret)
+		return -EINVAL;
+
+	priv_ep->flags &= ~(EP_STALLED | EP_STALL_PENDING);
+
+	if (request) {
+		if (trb)
+			*trb = trb_tmp;
+
+		cdns3_rearm_transfer(priv_ep, 1);
+	}
+
+	cdns3_start_all_request(priv_dev, priv_ep);
+	return ret;
+}
+
+/**
+ * cdns3_gadget_ep_set_halt Sets/clears stall on selected endpoint
+ * @ep: endpoint object to set/clear stall on
+ * @value: 1 for set stall, 0 for clear stall
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+int cdns3_gadget_ep_set_halt(struct usb_ep *ep, int value)
+{
+	struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
+	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!(priv_ep->flags & EP_ENABLED))
+		return -EPERM;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+
+	cdns3_select_ep(priv_dev, ep->desc->bEndpointAddress);
+
+	if (!value) {
+		priv_ep->flags &= ~EP_WEDGE;
+		ret = __cdns3_gadget_ep_clear_halt(priv_ep);
+	} else {
+		__cdns3_gadget_ep_set_halt(priv_ep);
+	}
+
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+
+	return ret;
+}
+
+extern const struct usb_ep_ops cdns3_gadget_ep0_ops;
+
+static const struct usb_ep_ops cdns3_gadget_ep_ops = {
+	.enable = cdns3_gadget_ep_enable,
+	.disable = cdns3_gadget_ep_disable,
+	.alloc_request = cdns3_gadget_ep_alloc_request,
+	.free_request = cdns3_gadget_ep_free_request,
+	.queue = cdns3_gadget_ep_queue,
+	.dequeue = cdns3_gadget_ep_dequeue,
+	.set_halt = cdns3_gadget_ep_set_halt,
+	.set_wedge = cdns3_gadget_ep_set_wedge,
+};
+
+/**
+ * cdns3_gadget_get_frame Returns number of actual ITP frame
+ * @gadget: gadget object
+ *
+ * Returns number of actual ITP frame
+ */
+static int cdns3_gadget_get_frame(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+
+	return readl(&priv_dev->regs->usb_itpn);
+}
+
+int __cdns3_gadget_wakeup(struct cdns3_device *priv_dev)
+{
+	enum usb_device_speed speed;
+
+	speed = cdns3_get_speed(priv_dev);
+
+	if (speed >= USB_SPEED_SUPER)
+		return 0;
+
+	/* Start driving resume signaling to indicate remote wakeup. */
+	writel(USB_CONF_LGO_L0, &priv_dev->regs->usb_conf);
+
+	return 0;
+}
+
+static int cdns3_gadget_wakeup(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	ret = __cdns3_gadget_wakeup(priv_dev);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return ret;
+}
+
+static int cdns3_gadget_set_selfpowered(struct usb_gadget *gadget,
+					int is_selfpowered)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_dev->is_selfpowered = !!is_selfpowered;
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return 0;
+}
+
+static int cdns3_gadget_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+
+	if (is_on) {
+		writel(USB_CONF_DEVEN, &priv_dev->regs->usb_conf);
+	} else {
+		writel(~0, &priv_dev->regs->ep_ists);
+		writel(~0, &priv_dev->regs->usb_ists);
+		writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+	}
+
+	return 0;
+}
+
+static void cdns3_gadget_config(struct cdns3_device *priv_dev)
+{
+	struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+	u32 reg;
+
+	cdns3_ep0_config(priv_dev);
+
+	/* enable interrupts for endpoint 0 (in and out) */
+	writel(EP_IEN_EP_OUT0 | EP_IEN_EP_IN0, &regs->ep_ien);
+
+	/*
+	 * Driver needs to modify LFPS minimal U1 Exit time for DEV_VER_TI_V1
+	 * revision of controller.
+	 */
+	if (priv_dev->dev_ver == DEV_VER_TI_V1) {
+		reg = readl(&regs->dbg_link1);
+
+		reg &= ~DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_MASK;
+		reg |= DBG_LINK1_LFPS_MIN_GEN_U1_EXIT(0x55) |
+		       DBG_LINK1_LFPS_MIN_GEN_U1_EXIT_SET;
+		writel(reg, &regs->dbg_link1);
+	}
+
+	/*
+	 * By default some platforms has set protected access to memory.
+	 * This cause problem with cache, so driver restore non-secure
+	 * access to memory.
+	 */
+	reg = readl(&regs->dma_axi_ctrl);
+	reg |= DMA_AXI_CTRL_MARPROT(DMA_AXI_CTRL_NON_SECURE) |
+	       DMA_AXI_CTRL_MAWPROT(DMA_AXI_CTRL_NON_SECURE);
+	writel(reg, &regs->dma_axi_ctrl);
+
+	/* enable generic interrupt*/
+	writel(USB_IEN_INIT, &regs->usb_ien);
+	writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
+	/*  keep Fast Access bit */
+	writel(PUSB_PWR_FST_REG_ACCESS, &priv_dev->regs->usb_pwr);
+
+	cdns3_configure_dmult(priv_dev, NULL);
+}
+
+/**
+ * cdns3_gadget_udc_start Gadget start
+ * @gadget: gadget object
+ * @driver: driver which operates on this gadget
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_gadget_udc_start(struct usb_gadget *gadget,
+				  struct usb_gadget_driver *driver)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	unsigned long flags;
+	enum usb_device_speed max_speed = driver->max_speed;
+
+	spin_lock_irqsave(&priv_dev->lock, flags);
+	priv_dev->gadget_driver = driver;
+
+	/* limit speed if necessary */
+	max_speed = min(driver->max_speed, gadget->max_speed);
+
+	switch (max_speed) {
+	case USB_SPEED_FULL:
+		writel(USB_CONF_SFORCE_FS, &priv_dev->regs->usb_conf);
+		writel(USB_CONF_USB3DIS, &priv_dev->regs->usb_conf);
+		break;
+	case USB_SPEED_HIGH:
+		writel(USB_CONF_USB3DIS, &priv_dev->regs->usb_conf);
+		break;
+	case USB_SPEED_SUPER:
+		break;
+	default:
+		dev_err(priv_dev->dev,
+			"invalid maximum_speed parameter %d\n",
+			max_speed);
+		fallthrough;
+	case USB_SPEED_UNKNOWN:
+		/* default to superspeed */
+		max_speed = USB_SPEED_SUPER;
+		break;
+	}
+
+	cdns3_gadget_config(priv_dev);
+	spin_unlock_irqrestore(&priv_dev->lock, flags);
+	return 0;
+}
+
+/**
+ * cdns3_gadget_udc_stop Stops gadget
+ * @gadget: gadget object
+ *
+ * Returns 0
+ */
+static int cdns3_gadget_udc_stop(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct cdns3_endpoint *priv_ep;
+	u32 bEndpointAddress;
+	struct usb_ep *ep;
+	int val;
+
+	priv_dev->gadget_driver = NULL;
+
+	priv_dev->onchip_used_size = 0;
+	priv_dev->out_mem_is_allocated = 0;
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+
+	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+		priv_ep = ep_to_cdns3_ep(ep);
+		bEndpointAddress = priv_ep->num | priv_ep->dir;
+		cdns3_select_ep(priv_dev, bEndpointAddress);
+		writel(EP_CMD_EPRST, &priv_dev->regs->ep_cmd);
+		readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val,
+					  !(val & EP_CMD_EPRST), 1, 100);
+
+		priv_ep->flags &= ~EP_CLAIMED;
+	}
+
+	/* disable interrupt for device */
+	writel(0, &priv_dev->regs->usb_ien);
+	writel(0, &priv_dev->regs->usb_pwr);
+	writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+
+	return 0;
+}
+
+/**
+ * cdns3_gadget_check_config - ensure cdns3 can support the USB configuration
+ * @gadget: pointer to the USB gadget
+ *
+ * Used to record the maximum number of endpoints being used in a USB composite
+ * device. (across all configurations)  This is to be used in the calculation
+ * of the TXFIFO sizes when resizing internal memory for individual endpoints.
+ * It will help ensured that the resizing logic reserves enough space for at
+ * least one max packet.
+ */
+static int cdns3_gadget_check_config(struct usb_gadget *gadget)
+{
+	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct usb_ep *ep;
+	int n_in = 0;
+	int total;
+
+	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
+		if (ep->claimed && (ep->address & USB_DIR_IN))
+			n_in++;
+	}
+
+	/* 2KB are reserved for EP0, 1KB for out*/
+	total = 2 + n_in + 1;
+
+	if (total > priv_dev->onchip_buffers)
+		return -ENOMEM;
+
+	priv_dev->ep_buf_size = priv_dev->ep_iso_burst =
+			(priv_dev->onchip_buffers - 2) / (n_in + 1);
+
+	return 0;
+}
+
+static const struct usb_gadget_ops cdns3_gadget_ops = {
+	.get_frame = cdns3_gadget_get_frame,
+	.wakeup = cdns3_gadget_wakeup,
+	.set_selfpowered = cdns3_gadget_set_selfpowered,
+	.pullup = cdns3_gadget_pullup,
+	.udc_start = cdns3_gadget_udc_start,
+	.udc_stop = cdns3_gadget_udc_stop,
+	.match_ep = cdns3_gadget_match_ep,
+	.check_config = cdns3_gadget_check_config,
+};
+
+static void cdns3_free_all_eps(struct cdns3_device *priv_dev)
+{
+	int i;
+
+	/* ep0 OUT point to ep0 IN. */
+	priv_dev->eps[16] = NULL;
+
+	for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++)
+		if (priv_dev->eps[i]) {
+			cdns3_free_trb_pool(priv_dev->eps[i]);
+			devm_kfree(priv_dev->dev, priv_dev->eps[i]);
+		}
+}
+
+/**
+ * cdns3_init_eps Initializes software endpoints of gadget
+ * @priv_dev: extended gadget object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_init_eps(struct cdns3_device *priv_dev)
+{
+	u32 ep_enabled_reg, iso_ep_reg;
+	struct cdns3_endpoint *priv_ep;
+	int ep_dir, ep_number;
+	u32 ep_mask;
+	int ret = 0;
+	int i;
+
+	/* Read it from USB_CAP3 to USB_CAP5 */
+	ep_enabled_reg = readl(&priv_dev->regs->usb_cap3);
+	iso_ep_reg = readl(&priv_dev->regs->usb_cap4);
+
+	dev_dbg(priv_dev->dev, "Initializing non-zero endpoints\n");
+
+	for (i = 0; i < CDNS3_ENDPOINTS_MAX_COUNT; i++) {
+		ep_dir = i >> 4;	/* i div 16 */
+		ep_number = i & 0xF;	/* i % 16 */
+		ep_mask = BIT(i);
+
+		if (!(ep_enabled_reg & ep_mask))
+			continue;
+
+		if (ep_dir && !ep_number) {
+			priv_dev->eps[i] = priv_dev->eps[0];
+			continue;
+		}
+
+		priv_ep = devm_kzalloc(priv_dev->dev, sizeof(*priv_ep),
+				       GFP_KERNEL);
+		if (!priv_ep)
+			goto err;
+
+		/* set parent of endpoint object */
+		priv_ep->cdns3_dev = priv_dev;
+		priv_dev->eps[i] = priv_ep;
+		priv_ep->num = ep_number;
+		priv_ep->dir = ep_dir ? USB_DIR_IN : USB_DIR_OUT;
+
+		if (!ep_number) {
+			ret = cdns3_init_ep0(priv_dev, priv_ep);
+			if (ret) {
+				dev_err(priv_dev->dev, "Failed to init ep0\n");
+				goto err;
+			}
+		} else {
+			snprintf(priv_ep->name, sizeof(priv_ep->name), "ep%d%s",
+				 ep_number, !!ep_dir ? "in" : "out");
+			priv_ep->endpoint.name = priv_ep->name;
+
+			usb_ep_set_maxpacket_limit(&priv_ep->endpoint,
+						   CDNS3_EP_MAX_PACKET_LIMIT);
+			priv_ep->endpoint.max_streams = CDNS3_EP_MAX_STREAMS;
+			priv_ep->endpoint.ops = &cdns3_gadget_ep_ops;
+			if (ep_dir)
+				priv_ep->endpoint.caps.dir_in = 1;
+			else
+				priv_ep->endpoint.caps.dir_out = 1;
+
+			if (iso_ep_reg & ep_mask)
+				priv_ep->endpoint.caps.type_iso = 1;
+
+			priv_ep->endpoint.caps.type_bulk = 1;
+			priv_ep->endpoint.caps.type_int = 1;
+
+			list_add_tail(&priv_ep->endpoint.ep_list,
+				      &priv_dev->gadget.ep_list);
+		}
+
+		priv_ep->flags = 0;
+
+		dev_dbg(priv_dev->dev, "Initialized  %s support: %s %s\n",
+			 priv_ep->name,
+			 priv_ep->endpoint.caps.type_bulk ? "BULK, INT" : "",
+			 priv_ep->endpoint.caps.type_iso ? "ISO" : "");
+
+		INIT_LIST_HEAD(&priv_ep->pending_req_list);
+		INIT_LIST_HEAD(&priv_ep->deferred_req_list);
+		INIT_LIST_HEAD(&priv_ep->wa2_descmiss_req_list);
+	}
+
+	return 0;
+err:
+	cdns3_free_all_eps(priv_dev);
+	return -ENOMEM;
+}
+
+static void cdns3_gadget_release(struct device *dev)
+{
+	struct cdns3_device *priv_dev = container_of(dev,
+			struct cdns3_device, gadget.dev);
+
+	kfree(priv_dev);
+}
+
+void cdns3_gadget_exit(struct cdns3 *cdns)
+{
+	struct cdns3_device *priv_dev;
+
+	priv_dev = cdns->gadget_dev;
+
+
+	pm_runtime_mark_last_busy(cdns->dev);
+	pm_runtime_put_autosuspend(cdns->dev);
+
+	usb_del_gadget(&priv_dev->gadget);
+	devm_free_irq(cdns->dev, cdns->dev_irq, priv_dev);
+
+	cdns3_free_all_eps(priv_dev);
+
+	while (!list_empty(&priv_dev->aligned_buf_list)) {
+		struct cdns3_aligned_buf *buf;
+
+		buf = cdns3_next_align_buf(&priv_dev->aligned_buf_list);
+		dma_free_coherent(priv_dev->sysdev, buf->size,
+				  buf->buf,
+				  buf->dma);
+
+		list_del(&buf->list);
+		kfree(buf);
+	}
+
+	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,
+			  priv_dev->setup_dma);
+
+	kfree(priv_dev->zlp_buf);
+	usb_put_gadget(&priv_dev->gadget);
+	cdns->gadget_dev = NULL;
+	cdns3_drd_gadget_off(cdns);
+}
+
+static int cdns3_gadget_start(struct cdns3 *cdns)
+{
+	struct cdns3_device *priv_dev;
+	u32 max_speed;
+	int ret;
+
+	priv_dev = kzalloc(sizeof(*priv_dev), GFP_KERNEL);
+	if (!priv_dev)
+		return -ENOMEM;
+
+	usb_initialize_gadget(cdns->dev, &priv_dev->gadget,
+			cdns3_gadget_release);
+	cdns->gadget_dev = priv_dev;
+	priv_dev->sysdev = cdns->dev;
+	priv_dev->dev = cdns->dev;
+	priv_dev->regs = cdns->dev_regs;
+
+	device_property_read_u16(priv_dev->dev, "cdns,on-chip-buff-size",
+				 &priv_dev->onchip_buffers);
+
+	if (priv_dev->onchip_buffers <=  0) {
+		u32 reg = readl(&priv_dev->regs->usb_cap2);
+
+		priv_dev->onchip_buffers = USB_CAP2_ACTUAL_MEM_SIZE(reg);
+	}
+
+	if (!priv_dev->onchip_buffers)
+		priv_dev->onchip_buffers = 256;
+
+	max_speed = usb_get_maximum_speed(cdns->dev);
+
+	/* Check the maximum_speed parameter */
+	switch (max_speed) {
+	case USB_SPEED_FULL:
+	case USB_SPEED_HIGH:
+	case USB_SPEED_SUPER:
+		break;
+	default:
+		dev_err(cdns->dev, "invalid maximum_speed parameter %d\n",
+			max_speed);
+		fallthrough;
+	case USB_SPEED_UNKNOWN:
+		/* default to superspeed */
+		max_speed = USB_SPEED_SUPER;
+		break;
+	}
+
+	/* fill gadget fields */
+	priv_dev->gadget.max_speed = max_speed;
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+	priv_dev->gadget.ops = &cdns3_gadget_ops;
+	priv_dev->gadget.name = "usb-ss-gadget";
+	priv_dev->gadget.quirk_avoids_skb_reserve = 1;
+	priv_dev->gadget.irq = cdns->dev_irq;
+
+	spin_lock_init(&priv_dev->lock);
+	INIT_WORK(&priv_dev->pending_status_wq,
+		  cdns3_pending_setup_status_handler);
+
+	INIT_WORK(&priv_dev->aligned_buf_wq,
+		  cdns3_free_aligned_request_buf);
+
+	/* initialize endpoint container */
+	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
+	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);
+
+	ret = cdns3_init_eps(priv_dev);
+	if (ret) {
+		dev_err(priv_dev->dev, "Failed to create endpoints\n");
+		goto err1;
+	}
+
+	/* allocate memory for setup packet buffer */
+	priv_dev->setup_buf = dma_alloc_coherent(priv_dev->sysdev, 8,
+						 &priv_dev->setup_dma, GFP_DMA);
+	if (!priv_dev->setup_buf) {
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	priv_dev->dev_ver = readl(&priv_dev->regs->usb_cap6);
+
+	dev_dbg(priv_dev->dev, "Device Controller version: %08x\n",
+		readl(&priv_dev->regs->usb_cap6));
+	dev_dbg(priv_dev->dev, "USB Capabilities:: %08x\n",
+		readl(&priv_dev->regs->usb_cap1));
+	dev_dbg(priv_dev->dev, "On-Chip memory configuration: %08x\n",
+		readl(&priv_dev->regs->usb_cap2));
+
+	priv_dev->dev_ver = GET_DEV_BASE_VERSION(priv_dev->dev_ver);
+	if (priv_dev->dev_ver >= DEV_VER_V2)
+		priv_dev->gadget.sg_supported = 1;
+
+	priv_dev->zlp_buf = kzalloc(CDNS3_EP_ZLP_BUF_SIZE, GFP_KERNEL);
+	if (!priv_dev->zlp_buf) {
+		ret = -ENOMEM;
+		goto err3;
+	}
+
+	/* add USB gadget device */
+	ret = usb_add_gadget(&priv_dev->gadget);
+	if (ret < 0) {
+		dev_err(priv_dev->dev, "Failed to add gadget\n");
+		goto err4;
+	}
+
+	return 0;
+err4:
+	kfree(priv_dev->zlp_buf);
+err3:
+	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,
+			  priv_dev->setup_dma);
+err2:
+	cdns3_free_all_eps(priv_dev);
+err1:
+	usb_put_gadget(&priv_dev->gadget);
+	cdns->gadget_dev = NULL;
+	return ret;
+}
+
+static int __cdns3_gadget_init(struct cdns3 *cdns)
+{
+	int ret = 0;
+
+	/* Ensure 32-bit DMA Mask in case we switched back from Host mode */
+	ret = dma_set_mask_and_coherent(cdns->dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(cdns->dev, "Failed to set dma mask: %d\n", ret);
+		return ret;
+	}
+
+	cdns3_drd_gadget_on(cdns);
+	pm_runtime_get_sync(cdns->dev);
+
+	ret = cdns3_gadget_start(cdns);
+	if (ret) {
+		pm_runtime_put_sync(cdns->dev);
+		return ret;
+	}
+
+	/*
+	 * Because interrupt line can be shared with other components in
+	 * driver it can't use IRQF_ONESHOT flag here.
+	 */
+	ret = devm_request_threaded_irq(cdns->dev, cdns->dev_irq,
+					cdns3_device_irq_handler,
+					cdns3_device_thread_irq_handler,
+					IRQF_SHARED, dev_name(cdns->dev),
+					cdns->gadget_dev);
+
+	if (ret)
+		goto err0;
+
+	return 0;
+err0:
+	cdns3_gadget_exit(cdns);
+	return ret;
+}
+
+static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup)
+__must_hold(&cdns->lock)
+{
+	struct cdns3_device *priv_dev = cdns->gadget_dev;
+
+	spin_unlock(&cdns->lock);
+	cdns3_disconnect_gadget(priv_dev);
+	spin_lock(&cdns->lock);
+
+	priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+	usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
+	cdns3_hw_reset_eps_config(priv_dev);
+
+	/* disable interrupt for device */
+	writel(0, &priv_dev->regs->usb_ien);
+
+	return 0;
+}
+
+static int cdns3_gadget_resume(struct cdns3 *cdns, bool hibernated)
+{
+	struct cdns3_device *priv_dev = cdns->gadget_dev;
+
+	if (!priv_dev->gadget_driver)
+		return 0;
+
+	cdns3_gadget_config(priv_dev);
+
+	return 0;
+}
+
+/**
+ * cdns3_gadget_init - initialize device structure
+ *
+ * @cdns: cdns3 instance
+ *
+ * This function initializes the gadget.
+ */
+int cdns3_gadget_init(struct cdns3 *cdns)
+{
+	struct cdns3_role_driver *rdrv;
+
+	rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
+	if (!rdrv)
+		return -ENOMEM;
+
+	rdrv->start	= __cdns3_gadget_init;
+	rdrv->stop	= cdns3_gadget_exit;
+	rdrv->suspend	= cdns3_gadget_suspend;
+	rdrv->resume	= cdns3_gadget_resume;
+	rdrv->state	= CDNS3_ROLE_STATE_INACTIVE;
+	rdrv->name	= "gadget";
+	cdns->roles[USB_ROLE_DEVICE] = rdrv;
+
+	return 0;
+}