Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 2494 insertions, 0 deletions

diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c
new file mode 100644
index 0000000000..275a6a2fa6
--- /dev/null
+++ b/drivers/usb/cdns3/cdnsp-ring.c
@@ -0,0 +1,2494 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence CDNSP DRD Driver.
+ *
+ * Copyright (C) 2020 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *
+ * Code based on Linux XHCI driver.
+ * Origin: Copyright (C) 2008 Intel Corp
+ */
+
+/*
+ * Ring initialization rules:
+ * 1. Each segment is initialized to zero, except for link TRBs.
+ * 2. Ring cycle state = 0. This represents Producer Cycle State (PCS) or
+ *    Consumer Cycle State (CCS), depending on ring function.
+ * 3. Enqueue pointer = dequeue pointer = address of first TRB in the segment.
+ *
+ * Ring behavior rules:
+ * 1. A ring is empty if enqueue == dequeue. This means there will always be at
+ *    least one free TRB in the ring. This is useful if you want to turn that
+ *    into a link TRB and expand the ring.
+ * 2. When incrementing an enqueue or dequeue pointer, if the next TRB is a
+ *    link TRB, then load the pointer with the address in the link TRB. If the
+ *    link TRB had its toggle bit set, you may need to update the ring cycle
+ *    state (see cycle bit rules). You may have to do this multiple times
+ *    until you reach a non-link TRB.
+ * 3. A ring is full if enqueue++ (for the definition of increment above)
+ *    equals the dequeue pointer.
+ *
+ * Cycle bit rules:
+ * 1. When a consumer increments a dequeue pointer and encounters a toggle bit
+ *    in a link TRB, it must toggle the ring cycle state.
+ * 2. When a producer increments an enqueue pointer and encounters a toggle bit
+ *    in a link TRB, it must toggle the ring cycle state.
+ *
+ * Producer rules:
+ * 1. Check if ring is full before you enqueue.
+ * 2. Write the ring cycle state to the cycle bit in the TRB you're enqueuing.
+ *    Update enqueue pointer between each write (which may update the ring
+ *    cycle state).
+ * 3. Notify consumer. If SW is producer, it rings the doorbell for command
+ *    and endpoint rings. If controller is the producer for the event ring,
+ *    and it generates an interrupt according to interrupt modulation rules.
+ *
+ * Consumer rules:
+ * 1. Check if TRB belongs to you. If the cycle bit == your ring cycle state,
+ *    the TRB is owned by the consumer.
+ * 2. Update dequeue pointer (which may update the ring cycle state) and
+ *    continue processing TRBs until you reach a TRB which is not owned by you.
+ * 3. Notify the producer. SW is the consumer for the event ring, and it
+ *    updates event ring dequeue pointer. Controller is the consumer for the
+ *    command and endpoint rings; it generates events on the event ring
+ *    for these.
+ */
+
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+
+#include "cdnsp-trace.h"
+#include "cdnsp-gadget.h"
+
+/*
+ * Returns zero if the TRB isn't in this segment, otherwise it returns the DMA
+ * address of the TRB.
+ */
+dma_addr_t cdnsp_trb_virt_to_dma(struct cdnsp_segment *seg,
+				 union cdnsp_trb *trb)
+{
+	unsigned long segment_offset = trb - seg->trbs;
+
+	if (trb < seg->trbs || segment_offset >= TRBS_PER_SEGMENT)
+		return 0;
+
+	return seg->dma + (segment_offset * sizeof(*trb));
+}
+
+static bool cdnsp_trb_is_noop(union cdnsp_trb *trb)
+{
+	return TRB_TYPE_NOOP_LE32(trb->generic.field[3]);
+}
+
+static bool cdnsp_trb_is_link(union cdnsp_trb *trb)
+{
+	return TRB_TYPE_LINK_LE32(trb->link.control);
+}
+
+bool cdnsp_last_trb_on_seg(struct cdnsp_segment *seg, union cdnsp_trb *trb)
+{
+	return trb == &seg->trbs[TRBS_PER_SEGMENT - 1];
+}
+
+bool cdnsp_last_trb_on_ring(struct cdnsp_ring *ring,
+			    struct cdnsp_segment *seg,
+			    union cdnsp_trb *trb)
+{
+	return cdnsp_last_trb_on_seg(seg, trb) && (seg->next == ring->first_seg);
+}
+
+static bool cdnsp_link_trb_toggles_cycle(union cdnsp_trb *trb)
+{
+	return le32_to_cpu(trb->link.control) & LINK_TOGGLE;
+}
+
+static void cdnsp_trb_to_noop(union cdnsp_trb *trb, u32 noop_type)
+{
+	if (cdnsp_trb_is_link(trb)) {
+		/* Unchain chained link TRBs. */
+		trb->link.control &= cpu_to_le32(~TRB_CHAIN);
+	} else {
+		trb->generic.field[0] = 0;
+		trb->generic.field[1] = 0;
+		trb->generic.field[2] = 0;
+		/* Preserve only the cycle bit of this TRB. */
+		trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
+		trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(noop_type));
+	}
+}
+
+/*
+ * Updates trb to point to the next TRB in the ring, and updates seg if the next
+ * TRB is in a new segment. This does not skip over link TRBs, and it does not
+ * effect the ring dequeue or enqueue pointers.
+ */
+static void cdnsp_next_trb(struct cdnsp_device *pdev,
+			   struct cdnsp_ring *ring,
+			   struct cdnsp_segment **seg,
+			   union cdnsp_trb **trb)
+{
+	if (cdnsp_trb_is_link(*trb)) {
+		*seg = (*seg)->next;
+		*trb = ((*seg)->trbs);
+	} else {
+		(*trb)++;
+	}
+}
+
+/*
+ * See Cycle bit rules. SW is the consumer for the event ring only.
+ * Don't make a ring full of link TRBs. That would be dumb and this would loop.
+ */
+void cdnsp_inc_deq(struct cdnsp_device *pdev, struct cdnsp_ring *ring)
+{
+	/* event ring doesn't have link trbs, check for last trb. */
+	if (ring->type == TYPE_EVENT) {
+		if (!cdnsp_last_trb_on_seg(ring->deq_seg, ring->dequeue)) {
+			ring->dequeue++;
+			goto out;
+		}
+
+		if (cdnsp_last_trb_on_ring(ring, ring->deq_seg, ring->dequeue))
+			ring->cycle_state ^= 1;
+
+		ring->deq_seg = ring->deq_seg->next;
+		ring->dequeue = ring->deq_seg->trbs;
+		goto out;
+	}
+
+	/* All other rings have link trbs. */
+	if (!cdnsp_trb_is_link(ring->dequeue)) {
+		ring->dequeue++;
+		ring->num_trbs_free++;
+	}
+	while (cdnsp_trb_is_link(ring->dequeue)) {
+		ring->deq_seg = ring->deq_seg->next;
+		ring->dequeue = ring->deq_seg->trbs;
+	}
+out:
+	trace_cdnsp_inc_deq(ring);
+}
+
+/*
+ * See Cycle bit rules. SW is the consumer for the event ring only.
+ * Don't make a ring full of link TRBs. That would be dumb and this would loop.
+ *
+ * If we've just enqueued a TRB that is in the middle of a TD (meaning the
+ * chain bit is set), then set the chain bit in all the following link TRBs.
+ * If we've enqueued the last TRB in a TD, make sure the following link TRBs
+ * have their chain bit cleared (so that each Link TRB is a separate TD).
+ *
+ * @more_trbs_coming:	Will you enqueue more TRBs before ringing the doorbell.
+ */
+static void cdnsp_inc_enq(struct cdnsp_device *pdev,
+			  struct cdnsp_ring *ring,
+			  bool more_trbs_coming)
+{
+	union cdnsp_trb *next;
+	u32 chain;
+
+	chain = le32_to_cpu(ring->enqueue->generic.field[3]) & TRB_CHAIN;
+
+	/* If this is not event ring, there is one less usable TRB. */
+	if (!cdnsp_trb_is_link(ring->enqueue))
+		ring->num_trbs_free--;
+	next = ++(ring->enqueue);
+
+	/* Update the dequeue pointer further if that was a link TRB */
+	while (cdnsp_trb_is_link(next)) {
+		/*
+		 * If the caller doesn't plan on enqueuing more TDs before
+		 * ringing the doorbell, then we don't want to give the link TRB
+		 * to the hardware just yet. We'll give the link TRB back in
+		 * cdnsp_prepare_ring() just before we enqueue the TD at the
+		 * top of the ring.
+		 */
+		if (!chain && !more_trbs_coming)
+			break;
+
+		next->link.control &= cpu_to_le32(~TRB_CHAIN);
+		next->link.control |= cpu_to_le32(chain);
+
+		/* Give this link TRB to the hardware */
+		wmb();
+		next->link.control ^= cpu_to_le32(TRB_CYCLE);
+
+		/* Toggle the cycle bit after the last ring segment. */
+		if (cdnsp_link_trb_toggles_cycle(next))
+			ring->cycle_state ^= 1;
+
+		ring->enq_seg = ring->enq_seg->next;
+		ring->enqueue = ring->enq_seg->trbs;
+		next = ring->enqueue;
+	}
+
+	trace_cdnsp_inc_enq(ring);
+}
+
+/*
+ * Check to see if there's room to enqueue num_trbs on the ring and make sure
+ * enqueue pointer will not advance into dequeue segment.
+ */
+static bool cdnsp_room_on_ring(struct cdnsp_device *pdev,
+			       struct cdnsp_ring *ring,
+			       unsigned int num_trbs)
+{
+	int num_trbs_in_deq_seg;
+
+	if (ring->num_trbs_free < num_trbs)
+		return false;
+
+	if (ring->type != TYPE_COMMAND && ring->type != TYPE_EVENT) {
+		num_trbs_in_deq_seg = ring->dequeue - ring->deq_seg->trbs;
+
+		if (ring->num_trbs_free < num_trbs + num_trbs_in_deq_seg)
+			return false;
+	}
+
+	return true;
+}
+
+/*
+ * Workaround for L1: controller has issue with resuming from L1 after
+ * setting doorbell for endpoint during L1 state. This function forces
+ * resume signal in such case.
+ */
+static void cdnsp_force_l0_go(struct cdnsp_device *pdev)
+{
+	if (pdev->active_port == &pdev->usb2_port && pdev->gadget.lpm_capable)
+		cdnsp_set_link_state(pdev, &pdev->active_port->regs->portsc, XDEV_U0);
+}
+
+/* Ring the doorbell after placing a command on the ring. */
+void cdnsp_ring_cmd_db(struct cdnsp_device *pdev)
+{
+	writel(DB_VALUE_CMD, &pdev->dba->cmd_db);
+}
+
+/*
+ * Ring the doorbell after placing a transfer on the ring.
+ * Returns true if doorbell was set, otherwise false.
+ */
+static bool cdnsp_ring_ep_doorbell(struct cdnsp_device *pdev,
+				   struct cdnsp_ep *pep,
+				   unsigned int stream_id)
+{
+	__le32 __iomem *reg_addr = &pdev->dba->ep_db;
+	unsigned int ep_state = pep->ep_state;
+	unsigned int db_value;
+
+	/*
+	 * Don't ring the doorbell for this endpoint if endpoint is halted or
+	 * disabled.
+	 */
+	if (ep_state & EP_HALTED || !(ep_state & EP_ENABLED))
+		return false;
+
+	/* For stream capable endpoints driver can ring doorbell only twice. */
+	if (pep->ep_state & EP_HAS_STREAMS) {
+		if (pep->stream_info.drbls_count >= 2)
+			return false;
+
+		pep->stream_info.drbls_count++;
+	}
+
+	pep->ep_state &= ~EP_STOPPED;
+
+	if (pep->idx == 0 && pdev->ep0_stage == CDNSP_DATA_STAGE &&
+	    !pdev->ep0_expect_in)
+		db_value = DB_VALUE_EP0_OUT(pep->idx, stream_id);
+	else
+		db_value = DB_VALUE(pep->idx, stream_id);
+
+	trace_cdnsp_tr_drbl(pep, stream_id);
+
+	writel(db_value, reg_addr);
+
+	cdnsp_force_l0_go(pdev);
+
+	/* Doorbell was set. */
+	return true;
+}
+
+/*
+ * Get the right ring for the given pep and stream_id.
+ * If the endpoint supports streams, boundary check the USB request's stream ID.
+ * If the endpoint doesn't support streams, return the singular endpoint ring.
+ */
+static struct cdnsp_ring *cdnsp_get_transfer_ring(struct cdnsp_device *pdev,
+						  struct cdnsp_ep *pep,
+						  unsigned int stream_id)
+{
+	if (!(pep->ep_state & EP_HAS_STREAMS))
+		return pep->ring;
+
+	if (stream_id == 0 || stream_id >= pep->stream_info.num_streams) {
+		dev_err(pdev->dev, "ERR: %s ring doesn't exist for SID: %d.\n",
+			pep->name, stream_id);
+		return NULL;
+	}
+
+	return pep->stream_info.stream_rings[stream_id];
+}
+
+static struct cdnsp_ring *
+	cdnsp_request_to_transfer_ring(struct cdnsp_device *pdev,
+				       struct cdnsp_request *preq)
+{
+	return cdnsp_get_transfer_ring(pdev, preq->pep,
+				       preq->request.stream_id);
+}
+
+/* Ring the doorbell for any rings with pending requests. */
+void cdnsp_ring_doorbell_for_active_rings(struct cdnsp_device *pdev,
+					  struct cdnsp_ep *pep)
+{
+	struct cdnsp_stream_info *stream_info;
+	unsigned int stream_id;
+	int ret;
+
+	if (pep->ep_state & EP_DIS_IN_RROGRESS)
+		return;
+
+	/* A ring has pending Request if its TD list is not empty. */
+	if (!(pep->ep_state & EP_HAS_STREAMS) && pep->number) {
+		if (pep->ring && !list_empty(&pep->ring->td_list))
+			cdnsp_ring_ep_doorbell(pdev, pep, 0);
+		return;
+	}
+
+	stream_info = &pep->stream_info;
+
+	for (stream_id = 1; stream_id < stream_info->num_streams; stream_id++) {
+		struct cdnsp_td *td, *td_temp;
+		struct cdnsp_ring *ep_ring;
+
+		if (stream_info->drbls_count >= 2)
+			return;
+
+		ep_ring = cdnsp_get_transfer_ring(pdev, pep, stream_id);
+		if (!ep_ring)
+			continue;
+
+		if (!ep_ring->stream_active || ep_ring->stream_rejected)
+			continue;
+
+		list_for_each_entry_safe(td, td_temp, &ep_ring->td_list,
+					 td_list) {
+			if (td->drbl)
+				continue;
+
+			ret = cdnsp_ring_ep_doorbell(pdev, pep, stream_id);
+			if (ret)
+				td->drbl = 1;
+		}
+	}
+}
+
+/*
+ * Get the hw dequeue pointer controller stopped on, either directly from the
+ * endpoint context, or if streams are in use from the stream context.
+ * The returned hw_dequeue contains the lowest four bits with cycle state
+ * and possible stream context type.
+ */
+static u64 cdnsp_get_hw_deq(struct cdnsp_device *pdev,
+			    unsigned int ep_index,
+			    unsigned int stream_id)
+{
+	struct cdnsp_stream_ctx *st_ctx;
+	struct cdnsp_ep *pep;
+
+	pep = &pdev->eps[stream_id];
+
+	if (pep->ep_state & EP_HAS_STREAMS) {
+		st_ctx = &pep->stream_info.stream_ctx_array[stream_id];
+		return le64_to_cpu(st_ctx->stream_ring);
+	}
+
+	return le64_to_cpu(pep->out_ctx->deq);
+}
+
+/*
+ * Move the controller endpoint ring dequeue pointer past cur_td.
+ * Record the new state of the controller endpoint ring dequeue segment,
+ * dequeue pointer, and new consumer cycle state in state.
+ * Update internal representation of the ring's dequeue pointer.
+ *
+ * We do this in three jumps:
+ *  - First we update our new ring state to be the same as when the
+ *    controller stopped.
+ *  - Then we traverse the ring to find the segment that contains
+ *    the last TRB in the TD. We toggle the controller new cycle state
+ *    when we pass any link TRBs with the toggle cycle bit set.
+ *  - Finally we move the dequeue state one TRB further, toggling the cycle bit
+ *    if we've moved it past a link TRB with the toggle cycle bit set.
+ */
+static void cdnsp_find_new_dequeue_state(struct cdnsp_device *pdev,
+					 struct cdnsp_ep *pep,
+					 unsigned int stream_id,
+					 struct cdnsp_td *cur_td,
+					 struct cdnsp_dequeue_state *state)
+{
+	bool td_last_trb_found = false;
+	struct cdnsp_segment *new_seg;
+	struct cdnsp_ring *ep_ring;
+	union cdnsp_trb *new_deq;
+	bool cycle_found = false;
+	u64 hw_dequeue;
+
+	ep_ring = cdnsp_get_transfer_ring(pdev, pep, stream_id);
+	if (!ep_ring)
+		return;
+
+	/*
+	 * Dig out the cycle state saved by the controller during the
+	 * stop endpoint command.
+	 */
+	hw_dequeue = cdnsp_get_hw_deq(pdev, pep->idx, stream_id);
+	new_seg = ep_ring->deq_seg;
+	new_deq = ep_ring->dequeue;
+	state->new_cycle_state = hw_dequeue & 0x1;
+	state->stream_id = stream_id;
+
+	/*
+	 * We want to find the pointer, segment and cycle state of the new trb
+	 * (the one after current TD's last_trb). We know the cycle state at
+	 * hw_dequeue, so walk the ring until both hw_dequeue and last_trb are
+	 * found.
+	 */
+	do {
+		if (!cycle_found && cdnsp_trb_virt_to_dma(new_seg, new_deq)
+		    == (dma_addr_t)(hw_dequeue & ~0xf)) {
+			cycle_found = true;
+
+			if (td_last_trb_found)
+				break;
+		}
+
+		if (new_deq == cur_td->last_trb)
+			td_last_trb_found = true;
+
+		if (cycle_found && cdnsp_trb_is_link(new_deq) &&
+		    cdnsp_link_trb_toggles_cycle(new_deq))
+			state->new_cycle_state ^= 0x1;
+
+		cdnsp_next_trb(pdev, ep_ring, &new_seg, &new_deq);
+
+		/* Search wrapped around, bail out. */
+		if (new_deq == pep->ring->dequeue) {
+			dev_err(pdev->dev,
+				"Error: Failed finding new dequeue state\n");
+			state->new_deq_seg = NULL;
+			state->new_deq_ptr = NULL;
+			return;
+		}
+
+	} while (!cycle_found || !td_last_trb_found);
+
+	state->new_deq_seg = new_seg;
+	state->new_deq_ptr = new_deq;
+
+	trace_cdnsp_new_deq_state(state);
+}
+
+/*
+ * flip_cycle means flip the cycle bit of all but the first and last TRB.
+ * (The last TRB actually points to the ring enqueue pointer, which is not part
+ * of this TD.) This is used to remove partially enqueued isoc TDs from a ring.
+ */
+static void cdnsp_td_to_noop(struct cdnsp_device *pdev,
+			     struct cdnsp_ring *ep_ring,
+			     struct cdnsp_td *td,
+			     bool flip_cycle)
+{
+	struct cdnsp_segment *seg = td->start_seg;
+	union cdnsp_trb *trb = td->first_trb;
+
+	while (1) {
+		cdnsp_trb_to_noop(trb, TRB_TR_NOOP);
+
+		/* flip cycle if asked to */
+		if (flip_cycle && trb != td->first_trb && trb != td->last_trb)
+			trb->generic.field[3] ^= cpu_to_le32(TRB_CYCLE);
+
+		if (trb == td->last_trb)
+			break;
+
+		cdnsp_next_trb(pdev, ep_ring, &seg, &trb);
+	}
+}
+
+/*
+ * This TD is defined by the TRBs starting at start_trb in start_seg and ending
+ * at end_trb, which may be in another segment. If the suspect DMA address is a
+ * TRB in this TD, this function returns that TRB's segment. Otherwise it
+ * returns 0.
+ */
+static struct cdnsp_segment *cdnsp_trb_in_td(struct cdnsp_device *pdev,
+					     struct cdnsp_segment *start_seg,
+					     union cdnsp_trb *start_trb,
+					     union cdnsp_trb *end_trb,
+					     dma_addr_t suspect_dma)
+{
+	struct cdnsp_segment *cur_seg;
+	union cdnsp_trb *temp_trb;
+	dma_addr_t end_seg_dma;
+	dma_addr_t end_trb_dma;
+	dma_addr_t start_dma;
+
+	start_dma = cdnsp_trb_virt_to_dma(start_seg, start_trb);
+	cur_seg = start_seg;
+
+	do {
+		if (start_dma == 0)
+			return NULL;
+
+		temp_trb = &cur_seg->trbs[TRBS_PER_SEGMENT - 1];
+		/* We may get an event for a Link TRB in the middle of a TD */
+		end_seg_dma = cdnsp_trb_virt_to_dma(cur_seg, temp_trb);
+		/* If the end TRB isn't in this segment, this is set to 0 */
+		end_trb_dma = cdnsp_trb_virt_to_dma(cur_seg, end_trb);
+
+		trace_cdnsp_looking_trb_in_td(suspect_dma, start_dma,
+					      end_trb_dma, cur_seg->dma,
+					      end_seg_dma);
+
+		if (end_trb_dma > 0) {
+			/*
+			 * The end TRB is in this segment, so suspect should
+			 * be here
+			 */
+			if (start_dma <= end_trb_dma) {
+				if (suspect_dma >= start_dma &&
+				    suspect_dma <= end_trb_dma) {
+					return cur_seg;
+				}
+			} else {
+				/*
+				 * Case for one segment with a
+				 * TD wrapped around to the top
+				 */
+				if ((suspect_dma >= start_dma &&
+				     suspect_dma <= end_seg_dma) ||
+				    (suspect_dma >= cur_seg->dma &&
+				     suspect_dma <= end_trb_dma)) {
+					return cur_seg;
+				}
+			}
+
+			return NULL;
+		}
+
+		/* Might still be somewhere in this segment */
+		if (suspect_dma >= start_dma && suspect_dma <= end_seg_dma)
+			return cur_seg;
+
+		cur_seg = cur_seg->next;
+		start_dma = cdnsp_trb_virt_to_dma(cur_seg, &cur_seg->trbs[0]);
+	} while (cur_seg != start_seg);
+
+	return NULL;
+}
+
+static void cdnsp_unmap_td_bounce_buffer(struct cdnsp_device *pdev,
+					 struct cdnsp_ring *ring,
+					 struct cdnsp_td *td)
+{
+	struct cdnsp_segment *seg = td->bounce_seg;
+	struct cdnsp_request *preq;
+	size_t len;
+
+	if (!seg)
+		return;
+
+	preq = td->preq;
+
+	trace_cdnsp_bounce_unmap(td->preq, seg->bounce_len, seg->bounce_offs,
+				 seg->bounce_dma, 0);
+
+	if (!preq->direction) {
+		dma_unmap_single(pdev->dev, seg->bounce_dma,
+				 ring->bounce_buf_len,  DMA_TO_DEVICE);
+		return;
+	}
+
+	dma_unmap_single(pdev->dev, seg->bounce_dma, ring->bounce_buf_len,
+			 DMA_FROM_DEVICE);
+
+	/* For in transfers we need to copy the data from bounce to sg */
+	len = sg_pcopy_from_buffer(preq->request.sg, preq->request.num_sgs,
+				   seg->bounce_buf, seg->bounce_len,
+				   seg->bounce_offs);
+	if (len != seg->bounce_len)
+		dev_warn(pdev->dev, "WARN Wrong bounce buffer read length: %zu != %d\n",
+			 len, seg->bounce_len);
+
+	seg->bounce_len = 0;
+	seg->bounce_offs = 0;
+}
+
+static int cdnsp_cmd_set_deq(struct cdnsp_device *pdev,
+			     struct cdnsp_ep *pep,
+			     struct cdnsp_dequeue_state *deq_state)
+{
+	struct cdnsp_ring *ep_ring;
+	int ret;
+
+	if (!deq_state->new_deq_ptr || !deq_state->new_deq_seg) {
+		cdnsp_ring_doorbell_for_active_rings(pdev, pep);
+		return 0;
+	}
+
+	cdnsp_queue_new_dequeue_state(pdev, pep, deq_state);
+	cdnsp_ring_cmd_db(pdev);
+	ret = cdnsp_wait_for_cmd_compl(pdev);
+
+	trace_cdnsp_handle_cmd_set_deq(cdnsp_get_slot_ctx(&pdev->out_ctx));
+	trace_cdnsp_handle_cmd_set_deq_ep(pep->out_ctx);
+
+	/*
+	 * Update the ring's dequeue segment and dequeue pointer
+	 * to reflect the new position.
+	 */
+	ep_ring = cdnsp_get_transfer_ring(pdev, pep, deq_state->stream_id);
+
+	if (cdnsp_trb_is_link(ep_ring->dequeue)) {
+		ep_ring->deq_seg = ep_ring->deq_seg->next;
+		ep_ring->dequeue = ep_ring->deq_seg->trbs;
+	}
+
+	while (ep_ring->dequeue != deq_state->new_deq_ptr) {
+		ep_ring->num_trbs_free++;
+		ep_ring->dequeue++;
+
+		if (cdnsp_trb_is_link(ep_ring->dequeue)) {
+			if (ep_ring->dequeue == deq_state->new_deq_ptr)
+				break;
+
+			ep_ring->deq_seg = ep_ring->deq_seg->next;
+			ep_ring->dequeue = ep_ring->deq_seg->trbs;
+		}
+	}
+
+	/*
+	 * Probably there was TIMEOUT during handling Set Dequeue Pointer
+	 * command. It's critical error and controller will be stopped.
+	 */
+	if (ret)
+		return -ESHUTDOWN;
+
+	/* Restart any rings with pending requests */
+	cdnsp_ring_doorbell_for_active_rings(pdev, pep);
+
+	return 0;
+}
+
+int cdnsp_remove_request(struct cdnsp_device *pdev,
+			 struct cdnsp_request *preq,
+			 struct cdnsp_ep *pep)
+{
+	struct cdnsp_dequeue_state deq_state;
+	struct cdnsp_td *cur_td = NULL;
+	struct cdnsp_ring *ep_ring;
+	struct cdnsp_segment *seg;
+	int status = -ECONNRESET;
+	int ret = 0;
+	u64 hw_deq;
+
+	memset(&deq_state, 0, sizeof(deq_state));
+
+	trace_cdnsp_remove_request(pep->out_ctx);
+	trace_cdnsp_remove_request_td(preq);
+
+	cur_td = &preq->td;
+	ep_ring = cdnsp_request_to_transfer_ring(pdev, preq);
+
+	/*
+	 * If we stopped on the TD we need to cancel, then we have to
+	 * move the controller endpoint ring dequeue pointer past
+	 * this TD.
+	 */
+	hw_deq = cdnsp_get_hw_deq(pdev, pep->idx, preq->request.stream_id);
+	hw_deq &= ~0xf;
+
+	seg = cdnsp_trb_in_td(pdev, cur_td->start_seg, cur_td->first_trb,
+			      cur_td->last_trb, hw_deq);
+
+	if (seg && (pep->ep_state & EP_ENABLED))
+		cdnsp_find_new_dequeue_state(pdev, pep, preq->request.stream_id,
+					     cur_td, &deq_state);
+	else
+		cdnsp_td_to_noop(pdev, ep_ring, cur_td, false);
+
+	/*
+	 * The event handler won't see a completion for this TD anymore,
+	 * so remove it from the endpoint ring's TD list.
+	 */
+	list_del_init(&cur_td->td_list);
+	ep_ring->num_tds--;
+	pep->stream_info.td_count--;
+
+	/*
+	 * During disconnecting all endpoint will be disabled so we don't
+	 * have to worry about updating dequeue pointer.
+	 */
+	if (pdev->cdnsp_state & CDNSP_STATE_DISCONNECT_PENDING) {
+		status = -ESHUTDOWN;
+		ret = cdnsp_cmd_set_deq(pdev, pep, &deq_state);
+	}
+
+	cdnsp_unmap_td_bounce_buffer(pdev, ep_ring, cur_td);
+	cdnsp_gadget_giveback(pep, cur_td->preq, status);
+
+	return ret;
+}
+
+static int cdnsp_update_port_id(struct cdnsp_device *pdev, u32 port_id)
+{
+	struct cdnsp_port *port = pdev->active_port;
+	u8 old_port = 0;
+
+	if (port && port->port_num == port_id)
+		return 0;
+
+	if (port)
+		old_port = port->port_num;
+
+	if (port_id == pdev->usb2_port.port_num) {
+		port = &pdev->usb2_port;
+	} else if (port_id == pdev->usb3_port.port_num) {
+		port  = &pdev->usb3_port;
+	} else {
+		dev_err(pdev->dev, "Port event with invalid port ID %d\n",
+			port_id);
+		return -EINVAL;
+	}
+
+	if (port_id != old_port) {
+		cdnsp_disable_slot(pdev);
+		pdev->active_port = port;
+		cdnsp_enable_slot(pdev);
+	}
+
+	if (port_id == pdev->usb2_port.port_num)
+		cdnsp_set_usb2_hardware_lpm(pdev, NULL, 1);
+	else
+		writel(PORT_U1_TIMEOUT(1) | PORT_U2_TIMEOUT(1),
+		       &pdev->usb3_port.regs->portpmsc);
+
+	return 0;
+}
+
+static void cdnsp_handle_port_status(struct cdnsp_device *pdev,
+				     union cdnsp_trb *event)
+{
+	struct cdnsp_port_regs __iomem *port_regs;
+	u32 portsc, cmd_regs;
+	bool port2 = false;
+	u32 link_state;
+	u32 port_id;
+
+	/* Port status change events always have a successful completion code */
+	if (GET_COMP_CODE(le32_to_cpu(event->generic.field[2])) != COMP_SUCCESS)
+		dev_err(pdev->dev, "ERR: incorrect PSC event\n");
+
+	port_id = GET_PORT_ID(le32_to_cpu(event->generic.field[0]));
+
+	if (cdnsp_update_port_id(pdev, port_id))
+		goto cleanup;
+
+	port_regs = pdev->active_port->regs;
+
+	if (port_id == pdev->usb2_port.port_num)
+		port2 = true;
+
+new_event:
+	portsc = readl(&port_regs->portsc);
+	writel(cdnsp_port_state_to_neutral(portsc) |
+	       (portsc & PORT_CHANGE_BITS), &port_regs->portsc);
+
+	trace_cdnsp_handle_port_status(pdev->active_port->port_num, portsc);
+
+	pdev->gadget.speed = cdnsp_port_speed(portsc);
+	link_state = portsc & PORT_PLS_MASK;
+
+	/* Port Link State change detected. */
+	if ((portsc & PORT_PLC)) {
+		if (!(pdev->cdnsp_state & CDNSP_WAKEUP_PENDING)  &&
+		    link_state == XDEV_RESUME) {
+			cmd_regs = readl(&pdev->op_regs->command);
+			if (!(cmd_regs & CMD_R_S))
+				goto cleanup;
+
+			if (DEV_SUPERSPEED_ANY(portsc)) {
+				cdnsp_set_link_state(pdev, &port_regs->portsc,
+						     XDEV_U0);
+
+				cdnsp_resume_gadget(pdev);
+			}
+		}
+
+		if ((pdev->cdnsp_state & CDNSP_WAKEUP_PENDING) &&
+		    link_state == XDEV_U0) {
+			pdev->cdnsp_state &= ~CDNSP_WAKEUP_PENDING;
+
+			cdnsp_force_header_wakeup(pdev, 1);
+			cdnsp_ring_cmd_db(pdev);
+			cdnsp_wait_for_cmd_compl(pdev);
+		}
+
+		if (link_state == XDEV_U0 && pdev->link_state == XDEV_U3 &&
+		    !DEV_SUPERSPEED_ANY(portsc))
+			cdnsp_resume_gadget(pdev);
+
+		if (link_state == XDEV_U3 &&  pdev->link_state != XDEV_U3)
+			cdnsp_suspend_gadget(pdev);
+
+		pdev->link_state = link_state;
+	}
+
+	if (portsc & PORT_CSC) {
+		/* Detach device. */
+		if (pdev->gadget.connected && !(portsc & PORT_CONNECT))
+			cdnsp_disconnect_gadget(pdev);
+
+		/* Attach device. */
+		if (portsc & PORT_CONNECT) {
+			if (!port2)
+				cdnsp_irq_reset(pdev);
+
+			usb_gadget_set_state(&pdev->gadget, USB_STATE_ATTACHED);
+		}
+	}
+
+	/* Port reset. */
+	if ((portsc & (PORT_RC | PORT_WRC)) && (portsc & PORT_CONNECT)) {
+		cdnsp_irq_reset(pdev);
+		pdev->u1_allowed = 0;
+		pdev->u2_allowed = 0;
+		pdev->may_wakeup = 0;
+	}
+
+	if (portsc & PORT_CEC)
+		dev_err(pdev->dev, "Port Over Current detected\n");
+
+	if (portsc & PORT_CEC)
+		dev_err(pdev->dev, "Port Configure Error detected\n");
+
+	if (readl(&port_regs->portsc) & PORT_CHANGE_BITS)
+		goto new_event;
+
+cleanup:
+	cdnsp_inc_deq(pdev, pdev->event_ring);
+}
+
+static void cdnsp_td_cleanup(struct cdnsp_device *pdev,
+			     struct cdnsp_td *td,
+			     struct cdnsp_ring *ep_ring,
+			     int *status)
+{
+	struct cdnsp_request *preq = td->preq;
+
+	/* if a bounce buffer was used to align this td then unmap it */
+	cdnsp_unmap_td_bounce_buffer(pdev, ep_ring, td);
+
+	/*
+	 * If the controller said we transferred more data than the buffer
+	 * length, Play it safe and say we didn't transfer anything.
+	 */
+	if (preq->request.actual > preq->request.length) {
+		preq->request.actual = 0;
+		*status = 0;
+	}
+
+	list_del_init(&td->td_list);
+	ep_ring->num_tds--;
+	preq->pep->stream_info.td_count--;
+
+	cdnsp_gadget_giveback(preq->pep, preq, *status);
+}
+
+static void cdnsp_finish_td(struct cdnsp_device *pdev,
+			    struct cdnsp_td *td,
+			    struct cdnsp_transfer_event *event,
+			    struct cdnsp_ep *ep,
+			    int *status)
+{
+	struct cdnsp_ring *ep_ring;
+	u32 trb_comp_code;
+
+	ep_ring = cdnsp_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
+	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
+
+	if (trb_comp_code == COMP_STOPPED_LENGTH_INVALID ||
+	    trb_comp_code == COMP_STOPPED ||
+	    trb_comp_code == COMP_STOPPED_SHORT_PACKET) {
+		/*
+		 * The Endpoint Stop Command completion will take care of any
+		 * stopped TDs. A stopped TD may be restarted, so don't update
+		 * the ring dequeue pointer or take this TD off any lists yet.
+		 */
+		return;
+	}
+
+	/* Update ring dequeue pointer */
+	while (ep_ring->dequeue != td->last_trb)
+		cdnsp_inc_deq(pdev, ep_ring);
+
+	cdnsp_inc_deq(pdev, ep_ring);
+
+	cdnsp_td_cleanup(pdev, td, ep_ring, status);
+}
+
+/* sum trb lengths from ring dequeue up to stop_trb, _excluding_ stop_trb */
+static int cdnsp_sum_trb_lengths(struct cdnsp_device *pdev,
+				 struct cdnsp_ring *ring,
+				 union cdnsp_trb *stop_trb)
+{
+	struct cdnsp_segment *seg = ring->deq_seg;
+	union cdnsp_trb *trb = ring->dequeue;
+	u32 sum;
+
+	for (sum = 0; trb != stop_trb; cdnsp_next_trb(pdev, ring, &seg, &trb)) {
+		if (!cdnsp_trb_is_noop(trb) && !cdnsp_trb_is_link(trb))
+			sum += TRB_LEN(le32_to_cpu(trb->generic.field[2]));
+	}
+	return sum;
+}
+
+static int cdnsp_giveback_first_trb(struct cdnsp_device *pdev,
+				    struct cdnsp_ep *pep,
+				    unsigned int stream_id,
+				    int start_cycle,
+				    struct cdnsp_generic_trb *start_trb)
+{
+	/*
+	 * Pass all the TRBs to the hardware at once and make sure this write
+	 * isn't reordered.
+	 */
+	wmb();
+
+	if (start_cycle)
+		start_trb->field[3] |= cpu_to_le32(start_cycle);
+	else
+		start_trb->field[3] &= cpu_to_le32(~TRB_CYCLE);
+
+	if ((pep->ep_state & EP_HAS_STREAMS) &&
+	    !pep->stream_info.first_prime_det) {
+		trace_cdnsp_wait_for_prime(pep, stream_id);
+		return 0;
+	}
+
+	return cdnsp_ring_ep_doorbell(pdev, pep, stream_id);
+}
+
+/*
+ * Process control tds, update USB request status and actual_length.
+ */
+static void cdnsp_process_ctrl_td(struct cdnsp_device *pdev,
+				  struct cdnsp_td *td,
+				  union cdnsp_trb *event_trb,
+				  struct cdnsp_transfer_event *event,
+				  struct cdnsp_ep *pep,
+				  int *status)
+{
+	struct cdnsp_ring *ep_ring;
+	u32 remaining;
+	u32 trb_type;
+
+	trb_type = TRB_FIELD_TO_TYPE(le32_to_cpu(event_trb->generic.field[3]));
+	ep_ring = cdnsp_dma_to_transfer_ring(pep, le64_to_cpu(event->buffer));
+	remaining = EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
+
+	/*
+	 * if on data stage then update the actual_length of the USB
+	 * request and flag it as set, so it won't be overwritten in the event
+	 * for the last TRB.
+	 */
+	if (trb_type == TRB_DATA) {
+		td->request_length_set = true;
+		td->preq->request.actual = td->preq->request.length - remaining;
+	}
+
+	/* at status stage */
+	if (!td->request_length_set)
+		td->preq->request.actual = td->preq->request.length;
+
+	if (pdev->ep0_stage == CDNSP_DATA_STAGE && pep->number == 0 &&
+	    pdev->three_stage_setup) {
+		td = list_entry(ep_ring->td_list.next, struct cdnsp_td,
+				td_list);
+		pdev->ep0_stage = CDNSP_STATUS_STAGE;
+
+		cdnsp_giveback_first_trb(pdev, pep, 0, ep_ring->cycle_state,
+					 &td->last_trb->generic);
+		return;
+	}
+
+	*status = 0;
+
+	cdnsp_finish_td(pdev, td, event, pep, status);
+}
+
+/*
+ * Process isochronous tds, update usb request status and actual_length.
+ */
+static void cdnsp_process_isoc_td(struct cdnsp_device *pdev,
+				  struct cdnsp_td *td,
+				  union cdnsp_trb *ep_trb,
+				  struct cdnsp_transfer_event *event,
+				  struct cdnsp_ep *pep,
+				  int status)
+{
+	struct cdnsp_request *preq = td->preq;
+	u32 remaining, requested, ep_trb_len;
+	bool sum_trbs_for_length = false;
+	struct cdnsp_ring *ep_ring;
+	u32 trb_comp_code;
+	u32 td_length;
+
+	ep_ring = cdnsp_dma_to_transfer_ring(pep, le64_to_cpu(event->buffer));
+	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
+	remaining = EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
+	ep_trb_len = TRB_LEN(le32_to_cpu(ep_trb->generic.field[2]));
+
+	requested = preq->request.length;
+
+	/* handle completion code */
+	switch (trb_comp_code) {
+	case COMP_SUCCESS:
+		preq->request.status = 0;
+		break;
+	case COMP_SHORT_PACKET:
+		preq->request.status = 0;
+		sum_trbs_for_length = true;
+		break;
+	case COMP_ISOCH_BUFFER_OVERRUN:
+	case COMP_BABBLE_DETECTED_ERROR:
+		preq->request.status = -EOVERFLOW;
+		break;
+	case COMP_STOPPED:
+		sum_trbs_for_length = true;
+		break;
+	case COMP_STOPPED_SHORT_PACKET:
+		/* field normally containing residue now contains transferred */
+		preq->request.status  = 0;
+		requested = remaining;
+		break;
+	case COMP_STOPPED_LENGTH_INVALID:
+		requested = 0;
+		remaining = 0;
+		break;
+	default:
+		sum_trbs_for_length = true;
+		preq->request.status = -1;
+		break;
+	}
+
+	if (sum_trbs_for_length) {
+		td_length = cdnsp_sum_trb_lengths(pdev, ep_ring, ep_trb);
+		td_length += ep_trb_len - remaining;
+	} else {
+		td_length = requested;
+	}
+
+	td->preq->request.actual += td_length;
+
+	cdnsp_finish_td(pdev, td, event, pep, &status);
+}
+
+static void cdnsp_skip_isoc_td(struct cdnsp_device *pdev,
+			       struct cdnsp_td *td,
+			       struct cdnsp_transfer_event *event,
+			       struct cdnsp_ep *pep,
+			       int status)
+{
+	struct cdnsp_ring *ep_ring;
+
+	ep_ring = cdnsp_dma_to_transfer_ring(pep, le64_to_cpu(event->buffer));
+	td->preq->request.status = -EXDEV;
+	td->preq->request.actual = 0;
+
+	/* Update ring dequeue pointer */
+	while (ep_ring->dequeue != td->last_trb)
+		cdnsp_inc_deq(pdev, ep_ring);
+
+	cdnsp_inc_deq(pdev, ep_ring);
+
+	cdnsp_td_cleanup(pdev, td, ep_ring, &status);
+}
+
+/*
+ * Process bulk and interrupt tds, update usb request status and actual_length.
+ */
+static void cdnsp_process_bulk_intr_td(struct cdnsp_device *pdev,
+				       struct cdnsp_td *td,
+				       union cdnsp_trb *ep_trb,
+				       struct cdnsp_transfer_event *event,
+				       struct cdnsp_ep *ep,
+				       int *status)
+{
+	u32 remaining, requested, ep_trb_len;
+	struct cdnsp_ring *ep_ring;
+	u32 trb_comp_code;
+
+	ep_ring = cdnsp_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
+	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
+	remaining = EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
+	ep_trb_len = TRB_LEN(le32_to_cpu(ep_trb->generic.field[2]));
+	requested = td->preq->request.length;
+
+	switch (trb_comp_code) {
+	case COMP_SUCCESS:
+	case COMP_SHORT_PACKET:
+		*status = 0;
+		break;
+	case COMP_STOPPED_SHORT_PACKET:
+		td->preq->request.actual = remaining;
+		goto finish_td;
+	case COMP_STOPPED_LENGTH_INVALID:
+		/* Stopped on ep trb with invalid length, exclude it. */
+		ep_trb_len = 0;
+		remaining = 0;
+		break;
+	}
+
+	if (ep_trb == td->last_trb)
+		ep_trb_len = requested - remaining;
+	else
+		ep_trb_len = cdnsp_sum_trb_lengths(pdev, ep_ring, ep_trb) +
+						   ep_trb_len - remaining;
+	td->preq->request.actual = ep_trb_len;
+
+finish_td:
+	ep->stream_info.drbls_count--;
+
+	cdnsp_finish_td(pdev, td, event, ep, status);
+}
+
+static void cdnsp_handle_tx_nrdy(struct cdnsp_device *pdev,
+				 struct cdnsp_transfer_event *event)
+{
+	struct cdnsp_generic_trb *generic;
+	struct cdnsp_ring *ep_ring;
+	struct cdnsp_ep *pep;
+	int cur_stream;
+	int ep_index;
+	int host_sid;
+	int dev_sid;
+
+	generic = (struct cdnsp_generic_trb *)event;
+	ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1;
+	dev_sid = TRB_TO_DEV_STREAM(le32_to_cpu(generic->field[0]));
+	host_sid = TRB_TO_HOST_STREAM(le32_to_cpu(generic->field[2]));
+
+	pep = &pdev->eps[ep_index];
+
+	if (!(pep->ep_state & EP_HAS_STREAMS))
+		return;
+
+	if (host_sid == STREAM_PRIME_ACK) {
+		pep->stream_info.first_prime_det = 1;
+		for (cur_stream = 1; cur_stream < pep->stream_info.num_streams;
+		    cur_stream++) {
+			ep_ring = pep->stream_info.stream_rings[cur_stream];
+			ep_ring->stream_active = 1;
+			ep_ring->stream_rejected = 0;
+		}
+	}
+
+	if (host_sid == STREAM_REJECTED) {
+		struct cdnsp_td *td, *td_temp;
+
+		pep->stream_info.drbls_count--;
+		ep_ring = pep->stream_info.stream_rings[dev_sid];
+		ep_ring->stream_active = 0;
+		ep_ring->stream_rejected = 1;
+
+		list_for_each_entry_safe(td, td_temp, &ep_ring->td_list,
+					 td_list) {
+			td->drbl = 0;
+		}
+	}
+
+	cdnsp_ring_doorbell_for_active_rings(pdev, pep);
+}
+
+/*
+ * If this function returns an error condition, it means it got a Transfer
+ * event with a corrupted TRB DMA address or endpoint is disabled.
+ */
+static int cdnsp_handle_tx_event(struct cdnsp_device *pdev,
+				 struct cdnsp_transfer_event *event)
+{
+	const struct usb_endpoint_descriptor *desc;
+	bool handling_skipped_tds = false;
+	struct cdnsp_segment *ep_seg;
+	struct cdnsp_ring *ep_ring;
+	int status = -EINPROGRESS;
+	union cdnsp_trb *ep_trb;
+	dma_addr_t ep_trb_dma;
+	struct cdnsp_ep *pep;
+	struct cdnsp_td *td;
+	u32 trb_comp_code;
+	int invalidate;
+	int ep_index;
+
+	invalidate = le32_to_cpu(event->flags) & TRB_EVENT_INVALIDATE;
+	ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1;
+	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
+	ep_trb_dma = le64_to_cpu(event->buffer);
+
+	pep = &pdev->eps[ep_index];
+	ep_ring = cdnsp_dma_to_transfer_ring(pep, le64_to_cpu(event->buffer));
+
+	/*
+	 * If device is disconnect then all requests will be dequeued
+	 * by upper layers as part of disconnect sequence.
+	 * We don't want handle such event to avoid racing.
+	 */
+	if (invalidate || !pdev->gadget.connected)
+		goto cleanup;
+
+	if (GET_EP_CTX_STATE(pep->out_ctx) == EP_STATE_DISABLED) {
+		trace_cdnsp_ep_disabled(pep->out_ctx);
+		goto err_out;
+	}
+
+	/* Some transfer events don't always point to a trb*/
+	if (!ep_ring) {
+		switch (trb_comp_code) {
+		case COMP_INVALID_STREAM_TYPE_ERROR:
+		case COMP_INVALID_STREAM_ID_ERROR:
+		case COMP_RING_UNDERRUN:
+		case COMP_RING_OVERRUN:
+			goto cleanup;
+		default:
+			dev_err(pdev->dev, "ERROR: %s event for unknown ring\n",
+				pep->name);
+			goto err_out;
+		}
+	}
+
+	/* Look for some error cases that need special treatment. */
+	switch (trb_comp_code) {
+	case COMP_BABBLE_DETECTED_ERROR:
+		status = -EOVERFLOW;
+		break;
+	case COMP_RING_UNDERRUN:
+	case COMP_RING_OVERRUN:
+		/*
+		 * When the Isoch ring is empty, the controller will generate
+		 * a Ring Overrun Event for IN Isoch endpoint or Ring
+		 * Underrun Event for OUT Isoch endpoint.
+		 */
+		goto cleanup;
+	case COMP_MISSED_SERVICE_ERROR:
+		/*
+		 * When encounter missed service error, one or more isoc tds
+		 * may be missed by controller.
+		 * Set skip flag of the ep_ring; Complete the missed tds as
+		 * short transfer when process the ep_ring next time.
+		 */
+		pep->skip = true;
+		break;
+	}
+
+	do {
+		/*
+		 * This TRB should be in the TD at the head of this ring's TD
+		 * list.
+		 */
+		if (list_empty(&ep_ring->td_list)) {
+			/*
+			 * Don't print warnings if it's due to a stopped
+			 * endpoint generating an extra completion event, or
+			 * a event for the last TRB of a short TD we already
+			 * got a short event for.
+			 * The short TD is already removed from the TD list.
+			 */
+			if (!(trb_comp_code == COMP_STOPPED ||
+			      trb_comp_code == COMP_STOPPED_LENGTH_INVALID ||
+			      ep_ring->last_td_was_short))
+				trace_cdnsp_trb_without_td(ep_ring,
+					(struct cdnsp_generic_trb *)event);
+
+			if (pep->skip) {
+				pep->skip = false;
+				trace_cdnsp_ep_list_empty_with_skip(pep, 0);
+			}
+
+			goto cleanup;
+		}
+
+		td = list_entry(ep_ring->td_list.next, struct cdnsp_td,
+				td_list);
+
+		/* Is this a TRB in the currently executing TD? */
+		ep_seg = cdnsp_trb_in_td(pdev, ep_ring->deq_seg,
+					 ep_ring->dequeue, td->last_trb,
+					 ep_trb_dma);
+
+		desc = td->preq->pep->endpoint.desc;
+
+		if (ep_seg) {
+			ep_trb = &ep_seg->trbs[(ep_trb_dma - ep_seg->dma)
+					       / sizeof(*ep_trb)];
+
+			trace_cdnsp_handle_transfer(ep_ring,
+					(struct cdnsp_generic_trb *)ep_trb);
+
+			if (pep->skip && usb_endpoint_xfer_isoc(desc) &&
+			    td->last_trb != ep_trb)
+				return -EAGAIN;
+		}
+
+		/*
+		 * Skip the Force Stopped Event. The event_trb(ep_trb_dma)
+		 * of FSE is not in the current TD pointed by ep_ring->dequeue
+		 * because that the hardware dequeue pointer still at the
+		 * previous TRB of the current TD. The previous TRB maybe a
+		 * Link TD or the last TRB of the previous TD. The command
+		 * completion handle will take care the rest.
+		 */
+		if (!ep_seg && (trb_comp_code == COMP_STOPPED ||
+				trb_comp_code == COMP_STOPPED_LENGTH_INVALID)) {
+			pep->skip = false;
+			goto cleanup;
+		}
+
+		if (!ep_seg) {
+			if (!pep->skip || !usb_endpoint_xfer_isoc(desc)) {
+				/* Something is busted, give up! */
+				dev_err(pdev->dev,
+					"ERROR Transfer event TRB DMA ptr not "
+					"part of current TD ep_index %d "
+					"comp_code %u\n", ep_index,
+					trb_comp_code);
+				return -EINVAL;
+			}
+
+			cdnsp_skip_isoc_td(pdev, td, event, pep, status);
+			goto cleanup;
+		}
+
+		if (trb_comp_code == COMP_SHORT_PACKET)
+			ep_ring->last_td_was_short = true;
+		else
+			ep_ring->last_td_was_short = false;
+
+		if (pep->skip) {
+			pep->skip = false;
+			cdnsp_skip_isoc_td(pdev, td, event, pep, status);
+			goto cleanup;
+		}
+
+		if (cdnsp_trb_is_noop(ep_trb))
+			goto cleanup;
+
+		if (usb_endpoint_xfer_control(desc))
+			cdnsp_process_ctrl_td(pdev, td, ep_trb, event, pep,
+					      &status);
+		else if (usb_endpoint_xfer_isoc(desc))
+			cdnsp_process_isoc_td(pdev, td, ep_trb, event, pep,
+					      status);
+		else
+			cdnsp_process_bulk_intr_td(pdev, td, ep_trb, event, pep,
+						   &status);
+cleanup:
+		handling_skipped_tds = pep->skip;
+
+		/*
+		 * Do not update event ring dequeue pointer if we're in a loop
+		 * processing missed tds.
+		 */
+		if (!handling_skipped_tds)
+			cdnsp_inc_deq(pdev, pdev->event_ring);
+
+	/*
+	 * If ep->skip is set, it means there are missed tds on the
+	 * endpoint ring need to take care of.
+	 * Process them as short transfer until reach the td pointed by
+	 * the event.
+	 */
+	} while (handling_skipped_tds);
+	return 0;
+
+err_out:
+	dev_err(pdev->dev, "@%016llx %08x %08x %08x %08x\n",
+		(unsigned long long)
+		cdnsp_trb_virt_to_dma(pdev->event_ring->deq_seg,
+				      pdev->event_ring->dequeue),
+		 lower_32_bits(le64_to_cpu(event->buffer)),
+		 upper_32_bits(le64_to_cpu(event->buffer)),
+		 le32_to_cpu(event->transfer_len),
+		 le32_to_cpu(event->flags));
+	return -EINVAL;
+}
+
+/*
+ * This function handles all events on the event ring.
+ * Returns true for "possibly more events to process" (caller should call
+ * again), otherwise false if done.
+ */
+static bool cdnsp_handle_event(struct cdnsp_device *pdev)
+{
+	unsigned int comp_code;
+	union cdnsp_trb *event;
+	bool update_ptrs = true;
+	u32 cycle_bit;
+	int ret = 0;
+	u32 flags;
+
+	event = pdev->event_ring->dequeue;
+	flags = le32_to_cpu(event->event_cmd.flags);
+	cycle_bit = (flags & TRB_CYCLE);
+
+	/* Does the controller or driver own the TRB? */
+	if (cycle_bit != pdev->event_ring->cycle_state)
+		return false;
+
+	trace_cdnsp_handle_event(pdev->event_ring, &event->generic);
+
+	/*
+	 * Barrier between reading the TRB_CYCLE (valid) flag above and any
+	 * reads of the event's flags/data below.
+	 */
+	rmb();
+
+	switch (flags & TRB_TYPE_BITMASK) {
+	case TRB_TYPE(TRB_COMPLETION):
+		/*
+		 * Command can't be handled in interrupt context so just
+		 * increment command ring dequeue pointer.
+		 */
+		cdnsp_inc_deq(pdev, pdev->cmd_ring);
+		break;
+	case TRB_TYPE(TRB_PORT_STATUS):
+		cdnsp_handle_port_status(pdev, event);
+		update_ptrs = false;
+		break;
+	case TRB_TYPE(TRB_TRANSFER):
+		ret = cdnsp_handle_tx_event(pdev, &event->trans_event);
+		if (ret >= 0)
+			update_ptrs = false;
+		break;
+	case TRB_TYPE(TRB_SETUP):
+		pdev->ep0_stage = CDNSP_SETUP_STAGE;
+		pdev->setup_id = TRB_SETUPID_TO_TYPE(flags);
+		pdev->setup_speed = TRB_SETUP_SPEEDID(flags);
+		pdev->setup = *((struct usb_ctrlrequest *)
+				&event->trans_event.buffer);
+
+		cdnsp_setup_analyze(pdev);
+		break;
+	case TRB_TYPE(TRB_ENDPOINT_NRDY):
+		cdnsp_handle_tx_nrdy(pdev, &event->trans_event);
+		break;
+	case TRB_TYPE(TRB_HC_EVENT): {
+		comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2]));
+
+		switch (comp_code) {
+		case COMP_EVENT_RING_FULL_ERROR:
+			dev_err(pdev->dev, "Event Ring Full\n");
+			break;
+		default:
+			dev_err(pdev->dev, "Controller error code 0x%02x\n",
+				comp_code);
+		}
+
+		break;
+	}
+	case TRB_TYPE(TRB_MFINDEX_WRAP):
+	case TRB_TYPE(TRB_DRB_OVERFLOW):
+		break;
+	default:
+		dev_warn(pdev->dev, "ERROR unknown event type %ld\n",
+			 TRB_FIELD_TO_TYPE(flags));
+	}
+
+	if (update_ptrs)
+		/* Update SW event ring dequeue pointer. */
+		cdnsp_inc_deq(pdev, pdev->event_ring);
+
+	/*
+	 * Caller will call us again to check if there are more items
+	 * on the event ring.
+	 */
+	return true;
+}
+
+irqreturn_t cdnsp_thread_irq_handler(int irq, void *data)
+{
+	struct cdnsp_device *pdev = (struct cdnsp_device *)data;
+	union cdnsp_trb *event_ring_deq;
+	unsigned long flags;
+	int counter = 0;
+
+	local_bh_disable();
+	spin_lock_irqsave(&pdev->lock, flags);
+
+	if (pdev->cdnsp_state & (CDNSP_STATE_HALTED | CDNSP_STATE_DYING)) {
+		/*
+		 * While removing or stopping driver there may still be deferred
+		 * not handled interrupt which should not be treated as error.
+		 * Driver should simply ignore it.
+		 */
+		if (pdev->gadget_driver)
+			cdnsp_died(pdev);
+
+		spin_unlock_irqrestore(&pdev->lock, flags);
+		local_bh_enable();
+		return IRQ_HANDLED;
+	}
+
+	event_ring_deq = pdev->event_ring->dequeue;
+
+	while (cdnsp_handle_event(pdev)) {
+		if (++counter >= TRBS_PER_EV_DEQ_UPDATE) {
+			cdnsp_update_erst_dequeue(pdev, event_ring_deq, 0);
+			event_ring_deq = pdev->event_ring->dequeue;
+			counter = 0;
+		}
+	}
+
+	cdnsp_update_erst_dequeue(pdev, event_ring_deq, 1);
+
+	spin_unlock_irqrestore(&pdev->lock, flags);
+	local_bh_enable();
+
+	return IRQ_HANDLED;
+}
+
+irqreturn_t cdnsp_irq_handler(int irq, void *priv)
+{
+	struct cdnsp_device *pdev = (struct cdnsp_device *)priv;
+	u32 irq_pending;
+	u32 status;
+
+	status = readl(&pdev->op_regs->status);
+
+	if (status == ~(u32)0) {
+		cdnsp_died(pdev);
+		return IRQ_HANDLED;
+	}
+
+	if (!(status & STS_EINT))
+		return IRQ_NONE;
+
+	writel(status | STS_EINT, &pdev->op_regs->status);
+	irq_pending = readl(&pdev->ir_set->irq_pending);
+	irq_pending |= IMAN_IP;
+	writel(irq_pending, &pdev->ir_set->irq_pending);
+
+	if (status & STS_FATAL) {
+		cdnsp_died(pdev);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_WAKE_THREAD;
+}
+
+/*
+ * Generic function for queuing a TRB on a ring.
+ * The caller must have checked to make sure there's room on the ring.
+ *
+ * @more_trbs_coming:	Will you enqueue more TRBs before setting doorbell?
+ */
+static void cdnsp_queue_trb(struct cdnsp_device *pdev, struct cdnsp_ring *ring,
+			    bool more_trbs_coming, u32 field1, u32 field2,
+			    u32 field3, u32 field4)
+{
+	struct cdnsp_generic_trb *trb;
+
+	trb = &ring->enqueue->generic;
+
+	trb->field[0] = cpu_to_le32(field1);
+	trb->field[1] = cpu_to_le32(field2);
+	trb->field[2] = cpu_to_le32(field3);
+	trb->field[3] = cpu_to_le32(field4);
+
+	trace_cdnsp_queue_trb(ring, trb);
+	cdnsp_inc_enq(pdev, ring, more_trbs_coming);
+}
+
+/*
+ * Does various checks on the endpoint ring, and makes it ready to
+ * queue num_trbs.
+ */
+static int cdnsp_prepare_ring(struct cdnsp_device *pdev,
+			      struct cdnsp_ring *ep_ring,
+			      u32 ep_state, unsigned
+			      int num_trbs,
+			      gfp_t mem_flags)
+{
+	unsigned int num_trbs_needed;
+
+	/* Make sure the endpoint has been added to controller schedule. */
+	switch (ep_state) {
+	case EP_STATE_STOPPED:
+	case EP_STATE_RUNNING:
+	case EP_STATE_HALTED:
+		break;
+	default:
+		dev_err(pdev->dev, "ERROR: incorrect endpoint state\n");
+		return -EINVAL;
+	}
+
+	while (1) {
+		if (cdnsp_room_on_ring(pdev, ep_ring, num_trbs))
+			break;
+
+		trace_cdnsp_no_room_on_ring("try ring expansion");
+
+		num_trbs_needed = num_trbs - ep_ring->num_trbs_free;
+		if (cdnsp_ring_expansion(pdev, ep_ring, num_trbs_needed,
+					 mem_flags)) {
+			dev_err(pdev->dev, "Ring expansion failed\n");
+			return -ENOMEM;
+		}
+	}
+
+	while (cdnsp_trb_is_link(ep_ring->enqueue)) {
+		ep_ring->enqueue->link.control |= cpu_to_le32(TRB_CHAIN);
+		/* The cycle bit must be set as the last operation. */
+		wmb();
+		ep_ring->enqueue->link.control ^= cpu_to_le32(TRB_CYCLE);
+
+		/* Toggle the cycle bit after the last ring segment. */
+		if (cdnsp_link_trb_toggles_cycle(ep_ring->enqueue))
+			ep_ring->cycle_state ^= 1;
+		ep_ring->enq_seg = ep_ring->enq_seg->next;
+		ep_ring->enqueue = ep_ring->enq_seg->trbs;
+	}
+	return 0;
+}
+
+static int cdnsp_prepare_transfer(struct cdnsp_device *pdev,
+				  struct cdnsp_request *preq,
+				  unsigned int num_trbs)
+{
+	struct cdnsp_ring *ep_ring;
+	int ret;
+
+	ep_ring = cdnsp_get_transfer_ring(pdev, preq->pep,
+					  preq->request.stream_id);
+	if (!ep_ring)
+		return -EINVAL;
+
+	ret = cdnsp_prepare_ring(pdev, ep_ring,
+				 GET_EP_CTX_STATE(preq->pep->out_ctx),
+				 num_trbs, GFP_ATOMIC);
+	if (ret)
+		return ret;
+
+	INIT_LIST_HEAD(&preq->td.td_list);
+	preq->td.preq = preq;
+
+	/* Add this TD to the tail of the endpoint ring's TD list. */
+	list_add_tail(&preq->td.td_list, &ep_ring->td_list);
+	ep_ring->num_tds++;
+	preq->pep->stream_info.td_count++;
+
+	preq->td.start_seg = ep_ring->enq_seg;
+	preq->td.first_trb = ep_ring->enqueue;
+
+	return 0;
+}
+
+static unsigned int cdnsp_count_trbs(u64 addr, u64 len)
+{
+	unsigned int num_trbs;
+
+	num_trbs = DIV_ROUND_UP(len + (addr & (TRB_MAX_BUFF_SIZE - 1)),
+				TRB_MAX_BUFF_SIZE);
+	if (num_trbs == 0)
+		num_trbs++;
+
+	return num_trbs;
+}
+
+static unsigned int count_trbs_needed(struct cdnsp_request *preq)
+{
+	return cdnsp_count_trbs(preq->request.dma, preq->request.length);
+}
+
+static unsigned int count_sg_trbs_needed(struct cdnsp_request *preq)
+{
+	unsigned int i, len, full_len, num_trbs = 0;
+	struct scatterlist *sg;
+
+	full_len = preq->request.length;
+
+	for_each_sg(preq->request.sg, sg, preq->request.num_sgs, i) {
+		len = sg_dma_len(sg);
+		num_trbs += cdnsp_count_trbs(sg_dma_address(sg), len);
+		len = min(len, full_len);
+		full_len -= len;
+		if (full_len == 0)
+			break;
+	}
+
+	return num_trbs;
+}
+
+static void cdnsp_check_trb_math(struct cdnsp_request *preq, int running_total)
+{
+	if (running_total != preq->request.length)
+		dev_err(preq->pep->pdev->dev,
+			"%s - Miscalculated tx length, "
+			"queued %#x, asked for %#x (%d)\n",
+			preq->pep->name, running_total,
+			preq->request.length, preq->request.actual);
+}
+
+/*
+ * TD size is the number of max packet sized packets remaining in the TD
+ * (*not* including this TRB).
+ *
+ * Total TD packet count = total_packet_count =
+ *     DIV_ROUND_UP(TD size in bytes / wMaxPacketSize)
+ *
+ * Packets transferred up to and including this TRB = packets_transferred =
+ *     rounddown(total bytes transferred including this TRB / wMaxPacketSize)
+ *
+ * TD size = total_packet_count - packets_transferred
+ *
+ * It must fit in bits 21:17, so it can't be bigger than 31.
+ * This is taken care of in the TRB_TD_SIZE() macro
+ *
+ * The last TRB in a TD must have the TD size set to zero.
+ */
+static u32 cdnsp_td_remainder(struct cdnsp_device *pdev,
+			      int transferred,
+			      int trb_buff_len,
+			      unsigned int td_total_len,
+			      struct cdnsp_request *preq,
+			      bool more_trbs_coming,
+			      bool zlp)
+{
+	u32 maxp, total_packet_count;
+
+	/* Before ZLP driver needs set TD_SIZE = 1. */
+	if (zlp)
+		return 1;
+
+	/* One TRB with a zero-length data packet. */
+	if (!more_trbs_coming || (transferred == 0 && trb_buff_len == 0) ||
+	    trb_buff_len == td_total_len)
+		return 0;
+
+	maxp = usb_endpoint_maxp(preq->pep->endpoint.desc);
+	total_packet_count = DIV_ROUND_UP(td_total_len, maxp);
+
+	/* Queuing functions don't count the current TRB into transferred. */
+	return (total_packet_count - ((transferred + trb_buff_len) / maxp));
+}
+
+static int cdnsp_align_td(struct cdnsp_device *pdev,
+			  struct cdnsp_request *preq, u32 enqd_len,
+			  u32 *trb_buff_len, struct cdnsp_segment *seg)
+{
+	struct device *dev = pdev->dev;
+	unsigned int unalign;
+	unsigned int max_pkt;
+	u32 new_buff_len;
+
+	max_pkt = usb_endpoint_maxp(preq->pep->endpoint.desc);
+	unalign = (enqd_len + *trb_buff_len) % max_pkt;
+
+	/* We got lucky, last normal TRB data on segment is packet aligned. */
+	if (unalign == 0)
+		return 0;
+
+	/* Is the last nornal TRB alignable by splitting it. */
+	if (*trb_buff_len > unalign) {
+		*trb_buff_len -= unalign;
+		trace_cdnsp_bounce_align_td_split(preq, *trb_buff_len,
+						  enqd_len, 0, unalign);
+		return 0;
+	}
+
+	/*
+	 * We want enqd_len + trb_buff_len to sum up to a number aligned to
+	 * number which is divisible by the endpoint's wMaxPacketSize. IOW:
+	 * (size of currently enqueued TRBs + remainder) % wMaxPacketSize == 0.
+	 */
+	new_buff_len = max_pkt - (enqd_len % max_pkt);
+
+	if (new_buff_len > (preq->request.length - enqd_len))
+		new_buff_len = (preq->request.length - enqd_len);
+
+	/* Create a max max_pkt sized bounce buffer pointed to by last trb. */
+	if (preq->direction) {
+		sg_pcopy_to_buffer(preq->request.sg,
+				   preq->request.num_mapped_sgs,
+				   seg->bounce_buf, new_buff_len, enqd_len);
+		seg->bounce_dma = dma_map_single(dev, seg->bounce_buf,
+						 max_pkt, DMA_TO_DEVICE);
+	} else {
+		seg->bounce_dma = dma_map_single(dev, seg->bounce_buf,
+						 max_pkt, DMA_FROM_DEVICE);
+	}
+
+	if (dma_mapping_error(dev, seg->bounce_dma)) {
+		/* Try without aligning.*/
+		dev_warn(pdev->dev,
+			 "Failed mapping bounce buffer, not aligning\n");
+		return 0;
+	}
+
+	*trb_buff_len = new_buff_len;
+	seg->bounce_len = new_buff_len;
+	seg->bounce_offs = enqd_len;
+
+	trace_cdnsp_bounce_map(preq, new_buff_len, enqd_len, seg->bounce_dma,
+			       unalign);
+
+	/*
+	 * Bounce buffer successful aligned and seg->bounce_dma will be used
+	 * in transfer TRB as new transfer buffer address.
+	 */
+	return 1;
+}
+
+int cdnsp_queue_bulk_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq)
+{
+	unsigned int enqd_len, block_len, trb_buff_len, full_len;
+	unsigned int start_cycle, num_sgs = 0;
+	struct cdnsp_generic_trb *start_trb;
+	u32 field, length_field, remainder;
+	struct scatterlist *sg = NULL;
+	bool more_trbs_coming = true;
+	bool need_zero_pkt = false;
+	bool zero_len_trb = false;
+	struct cdnsp_ring *ring;
+	bool first_trb = true;
+	unsigned int num_trbs;
+	struct cdnsp_ep *pep;
+	u64 addr, send_addr;
+	int sent_len, ret;
+
+	ring = cdnsp_request_to_transfer_ring(pdev, preq);
+	if (!ring)
+		return -EINVAL;
+
+	full_len = preq->request.length;
+
+	if (preq->request.num_sgs) {
+		num_sgs = preq->request.num_sgs;
+		sg = preq->request.sg;
+		addr = (u64)sg_dma_address(sg);
+		block_len = sg_dma_len(sg);
+		num_trbs = count_sg_trbs_needed(preq);
+	} else {
+		num_trbs = count_trbs_needed(preq);
+		addr = (u64)preq->request.dma;
+		block_len = full_len;
+	}
+
+	pep = preq->pep;
+
+	/* Deal with request.zero - need one more td/trb. */
+	if (preq->request.zero && preq->request.length &&
+	    IS_ALIGNED(full_len, usb_endpoint_maxp(pep->endpoint.desc))) {
+		need_zero_pkt = true;
+		num_trbs++;
+	}
+
+	ret = cdnsp_prepare_transfer(pdev, preq, num_trbs);
+	if (ret)
+		return ret;
+
+	/*
+	 * Don't give the first TRB to the hardware (by toggling the cycle bit)
+	 * until we've finished creating all the other TRBs. The ring's cycle
+	 * state may change as we enqueue the other TRBs, so save it too.
+	 */
+	start_trb = &ring->enqueue->generic;
+	start_cycle = ring->cycle_state;
+	send_addr = addr;
+
+	/* Queue the TRBs, even if they are zero-length */
+	for (enqd_len = 0; zero_len_trb || first_trb || enqd_len < full_len;
+	     enqd_len += trb_buff_len) {
+		field = TRB_TYPE(TRB_NORMAL);
+
+		/* TRB buffer should not cross 64KB boundaries */
+		trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
+		trb_buff_len = min(trb_buff_len, block_len);
+		if (enqd_len + trb_buff_len > full_len)
+			trb_buff_len = full_len - enqd_len;
+
+		/* Don't change the cycle bit of the first TRB until later */
+		if (first_trb) {
+			first_trb = false;
+			if (start_cycle == 0)
+				field |= TRB_CYCLE;
+		} else {
+			field |= ring->cycle_state;
+		}
+
+		/*
+		 * Chain all the TRBs together; clear the chain bit in the last
+		 * TRB to indicate it's the last TRB in the chain.
+		 */
+		if (enqd_len + trb_buff_len < full_len || need_zero_pkt) {
+			field |= TRB_CHAIN;
+			if (cdnsp_trb_is_link(ring->enqueue + 1)) {
+				if (cdnsp_align_td(pdev, preq, enqd_len,
+						   &trb_buff_len,
+						   ring->enq_seg)) {
+					send_addr = ring->enq_seg->bounce_dma;
+					/* Assuming TD won't span 2 segs */
+					preq->td.bounce_seg = ring->enq_seg;
+				}
+			}
+		}
+
+		if (enqd_len + trb_buff_len >= full_len) {
+			if (need_zero_pkt && !zero_len_trb) {
+				zero_len_trb = true;
+			} else {
+				zero_len_trb = false;
+				field &= ~TRB_CHAIN;
+				field |= TRB_IOC;
+				more_trbs_coming = false;
+				need_zero_pkt = false;
+				preq->td.last_trb = ring->enqueue;
+			}
+		}
+
+		/* Only set interrupt on short packet for OUT endpoints. */
+		if (!preq->direction)
+			field |= TRB_ISP;
+
+		/* Set the TRB length, TD size, and interrupter fields. */
+		remainder = cdnsp_td_remainder(pdev, enqd_len, trb_buff_len,
+					       full_len, preq,
+					       more_trbs_coming,
+					       zero_len_trb);
+
+		length_field = TRB_LEN(trb_buff_len) | TRB_TD_SIZE(remainder) |
+			TRB_INTR_TARGET(0);
+
+		cdnsp_queue_trb(pdev, ring, more_trbs_coming,
+				lower_32_bits(send_addr),
+				upper_32_bits(send_addr),
+				length_field,
+				field);
+
+		addr += trb_buff_len;
+		sent_len = trb_buff_len;
+		while (sg && sent_len >= block_len) {
+			/* New sg entry */
+			--num_sgs;
+			sent_len -= block_len;
+			if (num_sgs != 0) {
+				sg = sg_next(sg);
+				block_len = sg_dma_len(sg);
+				addr = (u64)sg_dma_address(sg);
+				addr += sent_len;
+			}
+		}
+		block_len -= sent_len;
+		send_addr = addr;
+	}
+
+	cdnsp_check_trb_math(preq, enqd_len);
+	ret = cdnsp_giveback_first_trb(pdev, pep, preq->request.stream_id,
+				       start_cycle, start_trb);
+
+	if (ret)
+		preq->td.drbl = 1;
+
+	return 0;
+}
+
+int cdnsp_queue_ctrl_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq)
+{
+	u32 field, length_field, zlp = 0;
+	struct cdnsp_ep *pep = preq->pep;
+	struct cdnsp_ring *ep_ring;
+	int num_trbs;
+	u32 maxp;
+	int ret;
+
+	ep_ring = cdnsp_request_to_transfer_ring(pdev, preq);
+	if (!ep_ring)
+		return -EINVAL;
+
+	/* 1 TRB for data, 1 for status */
+	num_trbs = (pdev->three_stage_setup) ? 2 : 1;
+
+	maxp = usb_endpoint_maxp(pep->endpoint.desc);
+
+	if (preq->request.zero && preq->request.length &&
+	    (preq->request.length % maxp == 0)) {
+		num_trbs++;
+		zlp = 1;
+	}
+
+	ret = cdnsp_prepare_transfer(pdev, preq, num_trbs);
+	if (ret)
+		return ret;
+
+	/* If there's data, queue data TRBs */
+	if (preq->request.length > 0) {
+		field = TRB_TYPE(TRB_DATA);
+
+		if (zlp)
+			field |= TRB_CHAIN;
+		else
+			field |= TRB_IOC | (pdev->ep0_expect_in ? 0 : TRB_ISP);
+
+		if (pdev->ep0_expect_in)
+			field |= TRB_DIR_IN;
+
+		length_field = TRB_LEN(preq->request.length) |
+			       TRB_TD_SIZE(zlp) | TRB_INTR_TARGET(0);
+
+		cdnsp_queue_trb(pdev, ep_ring, true,
+				lower_32_bits(preq->request.dma),
+				upper_32_bits(preq->request.dma), length_field,
+				field | ep_ring->cycle_state |
+				TRB_SETUPID(pdev->setup_id) |
+				pdev->setup_speed);
+
+		if (zlp) {
+			field = TRB_TYPE(TRB_NORMAL) | TRB_IOC;
+
+			if (!pdev->ep0_expect_in)
+				field = TRB_ISP;
+
+			cdnsp_queue_trb(pdev, ep_ring, true,
+					lower_32_bits(preq->request.dma),
+					upper_32_bits(preq->request.dma), 0,
+					field | ep_ring->cycle_state |
+					TRB_SETUPID(pdev->setup_id) |
+					pdev->setup_speed);
+		}
+
+		pdev->ep0_stage = CDNSP_DATA_STAGE;
+	}
+
+	/* Save the DMA address of the last TRB in the TD. */
+	preq->td.last_trb = ep_ring->enqueue;
+
+	/* Queue status TRB. */
+	if (preq->request.length == 0)
+		field = ep_ring->cycle_state;
+	else
+		field = (ep_ring->cycle_state ^ 1);
+
+	if (preq->request.length > 0 && pdev->ep0_expect_in)
+		field |= TRB_DIR_IN;
+
+	if (pep->ep_state & EP0_HALTED_STATUS) {
+		pep->ep_state &= ~EP0_HALTED_STATUS;
+		field |= TRB_SETUPSTAT(TRB_SETUPSTAT_STALL);
+	} else {
+		field |= TRB_SETUPSTAT(TRB_SETUPSTAT_ACK);
+	}
+
+	cdnsp_queue_trb(pdev, ep_ring, false, 0, 0, TRB_INTR_TARGET(0),
+			field | TRB_IOC | TRB_SETUPID(pdev->setup_id) |
+			TRB_TYPE(TRB_STATUS) | pdev->setup_speed);
+
+	cdnsp_ring_ep_doorbell(pdev, pep, preq->request.stream_id);
+
+	return 0;
+}
+
+int cdnsp_cmd_stop_ep(struct cdnsp_device *pdev, struct cdnsp_ep *pep)
+{
+	u32 ep_state = GET_EP_CTX_STATE(pep->out_ctx);
+	int ret = 0;
+
+	if (ep_state == EP_STATE_STOPPED || ep_state == EP_STATE_DISABLED ||
+	    ep_state == EP_STATE_HALTED) {
+		trace_cdnsp_ep_stopped_or_disabled(pep->out_ctx);
+		goto ep_stopped;
+	}
+
+	cdnsp_queue_stop_endpoint(pdev, pep->idx);
+	cdnsp_ring_cmd_db(pdev);
+	ret = cdnsp_wait_for_cmd_compl(pdev);
+
+	trace_cdnsp_handle_cmd_stop_ep(pep->out_ctx);
+
+ep_stopped:
+	pep->ep_state |= EP_STOPPED;
+	return ret;
+}
+
+int cdnsp_cmd_flush_ep(struct cdnsp_device *pdev, struct cdnsp_ep *pep)
+{
+	int ret;
+
+	cdnsp_queue_flush_endpoint(pdev, pep->idx);
+	cdnsp_ring_cmd_db(pdev);
+	ret = cdnsp_wait_for_cmd_compl(pdev);
+
+	trace_cdnsp_handle_cmd_flush_ep(pep->out_ctx);
+
+	return ret;
+}
+
+/*
+ * The transfer burst count field of the isochronous TRB defines the number of
+ * bursts that are required to move all packets in this TD. Only SuperSpeed
+ * devices can burst up to bMaxBurst number of packets per service interval.
+ * This field is zero based, meaning a value of zero in the field means one
+ * burst. Basically, for everything but SuperSpeed devices, this field will be
+ * zero.
+ */
+static unsigned int cdnsp_get_burst_count(struct cdnsp_device *pdev,
+					  struct cdnsp_request *preq,
+					  unsigned int total_packet_count)
+{
+	unsigned int max_burst;
+
+	if (pdev->gadget.speed < USB_SPEED_SUPER)
+		return 0;
+
+	max_burst = preq->pep->endpoint.comp_desc->bMaxBurst;
+	return DIV_ROUND_UP(total_packet_count, max_burst + 1) - 1;
+}
+
+/*
+ * Returns the number of packets in the last "burst" of packets. This field is
+ * valid for all speeds of devices. USB 2.0 devices can only do one "burst", so
+ * the last burst packet count is equal to the total number of packets in the
+ * TD. SuperSpeed endpoints can have up to 3 bursts. All but the last burst
+ * must contain (bMaxBurst + 1) number of packets, but the last burst can
+ * contain 1 to (bMaxBurst + 1) packets.
+ */
+static unsigned int
+	cdnsp_get_last_burst_packet_count(struct cdnsp_device *pdev,
+					  struct cdnsp_request *preq,
+					  unsigned int total_packet_count)
+{
+	unsigned int max_burst;
+	unsigned int residue;
+
+	if (pdev->gadget.speed >= USB_SPEED_SUPER) {
+		/* bMaxBurst is zero based: 0 means 1 packet per burst. */
+		max_burst = preq->pep->endpoint.comp_desc->bMaxBurst;
+		residue = total_packet_count % (max_burst + 1);
+
+		/*
+		 * If residue is zero, the last burst contains (max_burst + 1)
+		 * number of packets, but the TLBPC field is zero-based.
+		 */
+		if (residue == 0)
+			return max_burst;
+
+		return residue - 1;
+	}
+	if (total_packet_count == 0)
+		return 0;
+
+	return total_packet_count - 1;
+}
+
+/* Queue function isoc transfer */
+int cdnsp_queue_isoc_tx(struct cdnsp_device *pdev,
+			struct cdnsp_request *preq)
+{
+	unsigned int trb_buff_len, td_len, td_remain_len, block_len;
+	unsigned int burst_count, last_burst_pkt;
+	unsigned int total_pkt_count, max_pkt;
+	struct cdnsp_generic_trb *start_trb;
+	struct scatterlist *sg = NULL;
+	bool more_trbs_coming = true;
+	struct cdnsp_ring *ep_ring;
+	unsigned int num_sgs = 0;
+	int running_total = 0;
+	u32 field, length_field;
+	u64 addr, send_addr;
+	int start_cycle;
+	int trbs_per_td;
+	int i, sent_len, ret;
+
+	ep_ring = preq->pep->ring;
+
+	td_len = preq->request.length;
+
+	if (preq->request.num_sgs) {
+		num_sgs = preq->request.num_sgs;
+		sg = preq->request.sg;
+		addr = (u64)sg_dma_address(sg);
+		block_len = sg_dma_len(sg);
+		trbs_per_td = count_sg_trbs_needed(preq);
+	} else {
+		addr = (u64)preq->request.dma;
+		block_len = td_len;
+		trbs_per_td = count_trbs_needed(preq);
+	}
+
+	ret = cdnsp_prepare_transfer(pdev, preq, trbs_per_td);
+	if (ret)
+		return ret;
+
+	start_trb = &ep_ring->enqueue->generic;
+	start_cycle = ep_ring->cycle_state;
+	td_remain_len = td_len;
+	send_addr = addr;
+
+	max_pkt = usb_endpoint_maxp(preq->pep->endpoint.desc);
+	total_pkt_count = DIV_ROUND_UP(td_len, max_pkt);
+
+	/* A zero-length transfer still involves at least one packet. */
+	if (total_pkt_count == 0)
+		total_pkt_count++;
+
+	burst_count = cdnsp_get_burst_count(pdev, preq, total_pkt_count);
+	last_burst_pkt = cdnsp_get_last_burst_packet_count(pdev, preq,
+							   total_pkt_count);
+
+	/*
+	 * Set isoc specific data for the first TRB in a TD.
+	 * Prevent HW from getting the TRBs by keeping the cycle state
+	 * inverted in the first TDs isoc TRB.
+	 */
+	field = TRB_TYPE(TRB_ISOC) | TRB_TLBPC(last_burst_pkt) |
+		TRB_SIA | TRB_TBC(burst_count);
+
+	if (!start_cycle)
+		field |= TRB_CYCLE;
+
+	/* Fill the rest of the TRB fields, and remaining normal TRBs. */
+	for (i = 0; i < trbs_per_td; i++) {
+		u32 remainder;
+
+		/* Calculate TRB length. */
+		trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
+		trb_buff_len = min(trb_buff_len, block_len);
+		if (trb_buff_len > td_remain_len)
+			trb_buff_len = td_remain_len;
+
+		/* Set the TRB length, TD size, & interrupter fields. */
+		remainder = cdnsp_td_remainder(pdev, running_total,
+					       trb_buff_len, td_len, preq,
+					       more_trbs_coming, 0);
+
+		length_field = TRB_LEN(trb_buff_len) | TRB_TD_SIZE(remainder) |
+			TRB_INTR_TARGET(0);
+
+		/* Only first TRB is isoc, overwrite otherwise. */
+		if (i) {
+			field = TRB_TYPE(TRB_NORMAL) | ep_ring->cycle_state;
+			length_field |= TRB_TD_SIZE(remainder);
+		} else {
+			length_field |= TRB_TD_SIZE_TBC(burst_count);
+		}
+
+		/* Only set interrupt on short packet for OUT EPs. */
+		if (usb_endpoint_dir_out(preq->pep->endpoint.desc))
+			field |= TRB_ISP;
+
+		/* Set the chain bit for all except the last TRB. */
+		if (i < trbs_per_td - 1) {
+			more_trbs_coming = true;
+			field |= TRB_CHAIN;
+		} else {
+			more_trbs_coming = false;
+			preq->td.last_trb = ep_ring->enqueue;
+			field |= TRB_IOC;
+		}
+
+		cdnsp_queue_trb(pdev, ep_ring, more_trbs_coming,
+				lower_32_bits(send_addr), upper_32_bits(send_addr),
+				length_field, field);
+
+		running_total += trb_buff_len;
+		addr += trb_buff_len;
+		td_remain_len -= trb_buff_len;
+
+		sent_len = trb_buff_len;
+		while (sg && sent_len >= block_len) {
+			/* New sg entry */
+			--num_sgs;
+			sent_len -= block_len;
+			if (num_sgs != 0) {
+				sg = sg_next(sg);
+				block_len = sg_dma_len(sg);
+				addr = (u64)sg_dma_address(sg);
+				addr += sent_len;
+			}
+		}
+		block_len -= sent_len;
+		send_addr = addr;
+	}
+
+	/* Check TD length */
+	if (running_total != td_len) {
+		dev_err(pdev->dev, "ISOC TD length unmatch\n");
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	cdnsp_giveback_first_trb(pdev, preq->pep, preq->request.stream_id,
+				 start_cycle, start_trb);
+
+	return 0;
+
+cleanup:
+	/* Clean up a partially enqueued isoc transfer. */
+	list_del_init(&preq->td.td_list);
+	ep_ring->num_tds--;
+
+	/*
+	 * Use the first TD as a temporary variable to turn the TDs we've
+	 * queued into No-ops with a software-owned cycle bit.
+	 * That way the hardware won't accidentally start executing bogus TDs
+	 * when we partially overwrite them.
+	 * td->first_trb and td->start_seg are already set.
+	 */
+	preq->td.last_trb = ep_ring->enqueue;
+	/* Every TRB except the first & last will have its cycle bit flipped. */
+	cdnsp_td_to_noop(pdev, ep_ring, &preq->td, true);
+
+	/* Reset the ring enqueue back to the first TRB and its cycle bit. */
+	ep_ring->enqueue = preq->td.first_trb;
+	ep_ring->enq_seg = preq->td.start_seg;
+	ep_ring->cycle_state = start_cycle;
+	return ret;
+}
+
+/****		Command Ring Operations		****/
+/*
+ * Generic function for queuing a command TRB on the command ring.
+ * Driver queue only one command to ring in the moment.
+ */
+static void cdnsp_queue_command(struct cdnsp_device *pdev,
+				u32 field1,
+				u32 field2,
+				u32 field3,
+				u32 field4)
+{
+	cdnsp_prepare_ring(pdev, pdev->cmd_ring, EP_STATE_RUNNING, 1,
+			   GFP_ATOMIC);
+
+	pdev->cmd.command_trb = pdev->cmd_ring->enqueue;
+
+	cdnsp_queue_trb(pdev, pdev->cmd_ring, false, field1, field2,
+			field3, field4 | pdev->cmd_ring->cycle_state);
+}
+
+/* Queue a slot enable or disable request on the command ring */
+void cdnsp_queue_slot_control(struct cdnsp_device *pdev, u32 trb_type)
+{
+	cdnsp_queue_command(pdev, 0, 0, 0, TRB_TYPE(trb_type) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id));
+}
+
+/* Queue an address device command TRB */
+void cdnsp_queue_address_device(struct cdnsp_device *pdev,
+				dma_addr_t in_ctx_ptr,
+				enum cdnsp_setup_dev setup)
+{
+	cdnsp_queue_command(pdev, lower_32_bits(in_ctx_ptr),
+			    upper_32_bits(in_ctx_ptr), 0,
+			    TRB_TYPE(TRB_ADDR_DEV) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id) |
+			    (setup == SETUP_CONTEXT_ONLY ? TRB_BSR : 0));
+}
+
+/* Queue a reset device command TRB */
+void cdnsp_queue_reset_device(struct cdnsp_device *pdev)
+{
+	cdnsp_queue_command(pdev, 0, 0, 0, TRB_TYPE(TRB_RESET_DEV) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id));
+}
+
+/* Queue a configure endpoint command TRB */
+void cdnsp_queue_configure_endpoint(struct cdnsp_device *pdev,
+				    dma_addr_t in_ctx_ptr)
+{
+	cdnsp_queue_command(pdev, lower_32_bits(in_ctx_ptr),
+			    upper_32_bits(in_ctx_ptr), 0,
+			    TRB_TYPE(TRB_CONFIG_EP) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id));
+}
+
+/*
+ * Suspend is set to indicate "Stop Endpoint Command" is being issued to stop
+ * activity on an endpoint that is about to be suspended.
+ */
+void cdnsp_queue_stop_endpoint(struct cdnsp_device *pdev, unsigned int ep_index)
+{
+	cdnsp_queue_command(pdev, 0, 0, 0, SLOT_ID_FOR_TRB(pdev->slot_id) |
+			    EP_ID_FOR_TRB(ep_index) | TRB_TYPE(TRB_STOP_RING));
+}
+
+/* Set Transfer Ring Dequeue Pointer command. */
+void cdnsp_queue_new_dequeue_state(struct cdnsp_device *pdev,
+				   struct cdnsp_ep *pep,
+				   struct cdnsp_dequeue_state *deq_state)
+{
+	u32 trb_stream_id = STREAM_ID_FOR_TRB(deq_state->stream_id);
+	u32 trb_slot_id = SLOT_ID_FOR_TRB(pdev->slot_id);
+	u32 type = TRB_TYPE(TRB_SET_DEQ);
+	u32 trb_sct = 0;
+	dma_addr_t addr;
+
+	addr = cdnsp_trb_virt_to_dma(deq_state->new_deq_seg,
+				     deq_state->new_deq_ptr);
+
+	if (deq_state->stream_id)
+		trb_sct = SCT_FOR_TRB(SCT_PRI_TR);
+
+	cdnsp_queue_command(pdev, lower_32_bits(addr) | trb_sct |
+			    deq_state->new_cycle_state, upper_32_bits(addr),
+			    trb_stream_id, trb_slot_id |
+			    EP_ID_FOR_TRB(pep->idx) | type);
+}
+
+void cdnsp_queue_reset_ep(struct cdnsp_device *pdev, unsigned int ep_index)
+{
+	return cdnsp_queue_command(pdev, 0, 0, 0,
+				   SLOT_ID_FOR_TRB(pdev->slot_id) |
+				   EP_ID_FOR_TRB(ep_index) |
+				   TRB_TYPE(TRB_RESET_EP));
+}
+
+/*
+ * Queue a halt endpoint request on the command ring.
+ */
+void cdnsp_queue_halt_endpoint(struct cdnsp_device *pdev, unsigned int ep_index)
+{
+	cdnsp_queue_command(pdev, 0, 0, 0, TRB_TYPE(TRB_HALT_ENDPOINT) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id) |
+			    EP_ID_FOR_TRB(ep_index));
+}
+
+/*
+ * Queue a flush endpoint request on the command ring.
+ */
+void  cdnsp_queue_flush_endpoint(struct cdnsp_device *pdev,
+				 unsigned int ep_index)
+{
+	cdnsp_queue_command(pdev, 0, 0, 0, TRB_TYPE(TRB_FLUSH_ENDPOINT) |
+			    SLOT_ID_FOR_TRB(pdev->slot_id) |
+			    EP_ID_FOR_TRB(ep_index));
+}
+
+void cdnsp_force_header_wakeup(struct cdnsp_device *pdev, int intf_num)
+{
+	u32 lo, mid;
+
+	lo = TRB_FH_TO_PACKET_TYPE(TRB_FH_TR_PACKET) |
+	     TRB_FH_TO_DEVICE_ADDRESS(pdev->device_address);
+	mid = TRB_FH_TR_PACKET_DEV_NOT |
+	      TRB_FH_TO_NOT_TYPE(TRB_FH_TR_PACKET_FUNCTION_WAKE) |
+	      TRB_FH_TO_INTERFACE(intf_num);
+
+	cdnsp_queue_command(pdev, lo, mid, 0,
+			    TRB_TYPE(TRB_FORCE_HEADER) | SET_PORT_ID(2));
+}