Move DWC2 driver out of staging

The DWC2 driver should now be in good enough shape to move out of
staging. I have stress tested it overnight on RPI running mass
storage and Ethernet transfers in parallel, and for several days
on our proprietary PCI-based platform.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2119 insertions, 0 deletions

diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
new file mode 100644
index 000000000000..012f17ec1a37
--- /dev/null
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -0,0 +1,2119 @@
+/*
+ * hcd_intr.c - DesignWare HS OTG Controller host-mode interrupt handling
+ *
+ * Copyright (C) 2004-2013 Synopsys, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any
+ * later version.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * This file contains the interrupt handlers for Host mode
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include <linux/usb/hcd.h>
+#include <linux/usb/ch11.h>
+
+#include "core.h"
+#include "hcd.h"
+
+/* This function is for debug only */
+static void dwc2_track_missed_sofs(struct dwc2_hsotg *hsotg)
+{
+#ifdef CONFIG_USB_DWC2_TRACK_MISSED_SOFS
+	u16 curr_frame_number = hsotg->frame_number;
+
+	if (hsotg->frame_num_idx < FRAME_NUM_ARRAY_SIZE) {
+		if (((hsotg->last_frame_num + 1) & HFNUM_MAX_FRNUM) !=
+		    curr_frame_number) {
+			hsotg->frame_num_array[hsotg->frame_num_idx] =
+					curr_frame_number;
+			hsotg->last_frame_num_array[hsotg->frame_num_idx] =
+					hsotg->last_frame_num;
+			hsotg->frame_num_idx++;
+		}
+	} else if (!hsotg->dumped_frame_num_array) {
+		int i;
+
+		dev_info(hsotg->dev, "Frame     Last Frame\n");
+		dev_info(hsotg->dev, "-----     ----------\n");
+		for (i = 0; i < FRAME_NUM_ARRAY_SIZE; i++) {
+			dev_info(hsotg->dev, "0x%04x    0x%04x\n",
+				 hsotg->frame_num_array[i],
+				 hsotg->last_frame_num_array[i]);
+		}
+		hsotg->dumped_frame_num_array = 1;
+	}
+	hsotg->last_frame_num = curr_frame_number;
+#endif
+}
+
+static void dwc2_hc_handle_tt_clear(struct dwc2_hsotg *hsotg,
+				    struct dwc2_host_chan *chan,
+				    struct dwc2_qtd *qtd)
+{
+	struct urb *usb_urb;
+
+	if (!chan->qh)
+		return;
+
+	if (chan->qh->dev_speed == USB_SPEED_HIGH)
+		return;
+
+	if (!qtd->urb)
+		return;
+
+	usb_urb = qtd->urb->priv;
+	if (!usb_urb || !usb_urb->dev || !usb_urb->dev->tt)
+		return;
+
+	if (qtd->urb->status != -EPIPE && qtd->urb->status != -EREMOTEIO) {
+		chan->qh->tt_buffer_dirty = 1;
+		if (usb_hub_clear_tt_buffer(usb_urb))
+			/* Clear failed; let's hope things work anyway */
+			chan->qh->tt_buffer_dirty = 0;
+	}
+}
+
+/*
+ * Handles the start-of-frame interrupt in host mode. Non-periodic
+ * transactions may be queued to the DWC_otg controller for the current
+ * (micro)frame. Periodic transactions may be queued to the controller
+ * for the next (micro)frame.
+ */
+static void dwc2_sof_intr(struct dwc2_hsotg *hsotg)
+{
+	struct list_head *qh_entry;
+	struct dwc2_qh *qh;
+	enum dwc2_transaction_type tr_type;
+
+#ifdef DEBUG_SOF
+	dev_vdbg(hsotg->dev, "--Start of Frame Interrupt--\n");
+#endif
+
+	hsotg->frame_number = dwc2_hcd_get_frame_number(hsotg);
+
+	dwc2_track_missed_sofs(hsotg);
+
+	/* Determine whether any periodic QHs should be executed */
+	qh_entry = hsotg->periodic_sched_inactive.next;
+	while (qh_entry != &hsotg->periodic_sched_inactive) {
+		qh = list_entry(qh_entry, struct dwc2_qh, qh_list_entry);
+		qh_entry = qh_entry->next;
+		if (dwc2_frame_num_le(qh->sched_frame, hsotg->frame_number))
+			/*
+			 * Move QH to the ready list to be executed next
+			 * (micro)frame
+			 */
+			list_move(&qh->qh_list_entry,
+				  &hsotg->periodic_sched_ready);
+	}
+	tr_type = dwc2_hcd_select_transactions(hsotg);
+	if (tr_type != DWC2_TRANSACTION_NONE)
+		dwc2_hcd_queue_transactions(hsotg, tr_type);
+
+	/* Clear interrupt */
+	writel(GINTSTS_SOF, hsotg->regs + GINTSTS);
+}
+
+/*
+ * Handles the Rx FIFO Level Interrupt, which indicates that there is
+ * at least one packet in the Rx FIFO. The packets are moved from the FIFO to
+ * memory if the DWC_otg controller is operating in Slave mode.
+ */
+static void dwc2_rx_fifo_level_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 grxsts, chnum, bcnt, dpid, pktsts;
+	struct dwc2_host_chan *chan;
+
+	if (dbg_perio())
+		dev_vdbg(hsotg->dev, "--RxFIFO Level Interrupt--\n");
+
+	grxsts = readl(hsotg->regs + GRXSTSP);
+	chnum = (grxsts & GRXSTS_HCHNUM_MASK) >> GRXSTS_HCHNUM_SHIFT;
+	chan = hsotg->hc_ptr_array[chnum];
+	if (!chan) {
+		dev_err(hsotg->dev, "Unable to get corresponding channel\n");
+		return;
+	}
+
+	bcnt = (grxsts & GRXSTS_BYTECNT_MASK) >> GRXSTS_BYTECNT_SHIFT;
+	dpid = (grxsts & GRXSTS_DPID_MASK) >> GRXSTS_DPID_SHIFT;
+	pktsts = (grxsts & GRXSTS_PKTSTS_MASK) >> GRXSTS_PKTSTS_SHIFT;
+
+	/* Packet Status */
+	if (dbg_perio()) {
+		dev_vdbg(hsotg->dev, "    Ch num = %d\n", chnum);
+		dev_vdbg(hsotg->dev, "    Count = %d\n", bcnt);
+		dev_vdbg(hsotg->dev, "    DPID = %d, chan.dpid = %d\n", dpid,
+			 chan->data_pid_start);
+		dev_vdbg(hsotg->dev, "    PStatus = %d\n", pktsts);
+	}
+
+	switch (pktsts) {
+	case GRXSTS_PKTSTS_HCHIN:
+		/* Read the data into the host buffer */
+		if (bcnt > 0) {
+			dwc2_read_packet(hsotg, chan->xfer_buf, bcnt);
+
+			/* Update the HC fields for the next packet received */
+			chan->xfer_count += bcnt;
+			chan->xfer_buf += bcnt;
+		}
+		break;
+	case GRXSTS_PKTSTS_HCHIN_XFER_COMP:
+	case GRXSTS_PKTSTS_DATATOGGLEERR:
+	case GRXSTS_PKTSTS_HCHHALTED:
+		/* Handled in interrupt, just ignore data */
+		break;
+	default:
+		dev_err(hsotg->dev,
+			"RxFIFO Level Interrupt: Unknown status %d\n", pktsts);
+		break;
+	}
+}
+
+/*
+ * This interrupt occurs when the non-periodic Tx FIFO is half-empty. More
+ * data packets may be written to the FIFO for OUT transfers. More requests
+ * may be written to the non-periodic request queue for IN transfers. This
+ * interrupt is enabled only in Slave mode.
+ */
+static void dwc2_np_tx_fifo_empty_intr(struct dwc2_hsotg *hsotg)
+{
+	dev_vdbg(hsotg->dev, "--Non-Periodic TxFIFO Empty Interrupt--\n");
+	dwc2_hcd_queue_transactions(hsotg, DWC2_TRANSACTION_NON_PERIODIC);
+}
+
+/*
+ * This interrupt occurs when the periodic Tx FIFO is half-empty. More data
+ * packets may be written to the FIFO for OUT transfers. More requests may be
+ * written to the periodic request queue for IN transfers. This interrupt is
+ * enabled only in Slave mode.
+ */
+static void dwc2_perio_tx_fifo_empty_intr(struct dwc2_hsotg *hsotg)
+{
+	if (dbg_perio())
+		dev_vdbg(hsotg->dev, "--Periodic TxFIFO Empty Interrupt--\n");
+	dwc2_hcd_queue_transactions(hsotg, DWC2_TRANSACTION_PERIODIC);
+}
+
+static void dwc2_hprt0_enable(struct dwc2_hsotg *hsotg, u32 hprt0,
+			      u32 *hprt0_modify)
+{
+	struct dwc2_core_params *params = hsotg->core_params;
+	int do_reset = 0;
+	u32 usbcfg;
+	u32 prtspd;
+	u32 hcfg;
+	u32 fslspclksel;
+	u32 hfir;
+
+	dev_vdbg(hsotg->dev, "%s(%p)\n", __func__, hsotg);
+
+	/* Every time when port enables calculate HFIR.FrInterval */
+	hfir = readl(hsotg->regs + HFIR);
+	hfir &= ~HFIR_FRINT_MASK;
+	hfir |= dwc2_calc_frame_interval(hsotg) << HFIR_FRINT_SHIFT &
+		HFIR_FRINT_MASK;
+	writel(hfir, hsotg->regs + HFIR);
+
+	/* Check if we need to adjust the PHY clock speed for low power */
+	if (!params->host_support_fs_ls_low_power) {
+		/* Port has been enabled, set the reset change flag */
+		hsotg->flags.b.port_reset_change = 1;
+		return;
+	}
+
+	usbcfg = readl(hsotg->regs + GUSBCFG);
+	prtspd = (hprt0 & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
+
+	if (prtspd == HPRT0_SPD_LOW_SPEED || prtspd == HPRT0_SPD_FULL_SPEED) {
+		/* Low power */
+		if (!(usbcfg & GUSBCFG_PHY_LP_CLK_SEL)) {
+			/* Set PHY low power clock select for FS/LS devices */
+			usbcfg |= GUSBCFG_PHY_LP_CLK_SEL;
+			writel(usbcfg, hsotg->regs + GUSBCFG);
+			do_reset = 1;
+		}
+
+		hcfg = readl(hsotg->regs + HCFG);
+		fslspclksel = (hcfg & HCFG_FSLSPCLKSEL_MASK) >>
+			      HCFG_FSLSPCLKSEL_SHIFT;
+
+		if (prtspd == HPRT0_SPD_LOW_SPEED &&
+		    params->host_ls_low_power_phy_clk ==
+		    DWC2_HOST_LS_LOW_POWER_PHY_CLK_PARAM_6MHZ) {
+			/* 6 MHZ */
+			dev_vdbg(hsotg->dev,
+				 "FS_PHY programming HCFG to 6 MHz\n");
+			if (fslspclksel != HCFG_FSLSPCLKSEL_6_MHZ) {
+				fslspclksel = HCFG_FSLSPCLKSEL_6_MHZ;
+				hcfg &= ~HCFG_FSLSPCLKSEL_MASK;
+				hcfg |= fslspclksel << HCFG_FSLSPCLKSEL_SHIFT;
+				writel(hcfg, hsotg->regs + HCFG);
+				do_reset = 1;
+			}
+		} else {
+			/* 48 MHZ */
+			dev_vdbg(hsotg->dev,
+				 "FS_PHY programming HCFG to 48 MHz\n");
+			if (fslspclksel != HCFG_FSLSPCLKSEL_48_MHZ) {
+				fslspclksel = HCFG_FSLSPCLKSEL_48_MHZ;
+				hcfg &= ~HCFG_FSLSPCLKSEL_MASK;
+				hcfg |= fslspclksel << HCFG_FSLSPCLKSEL_SHIFT;
+				writel(hcfg, hsotg->regs + HCFG);
+				do_reset = 1;
+			}
+		}
+	} else {
+		/* Not low power */
+		if (usbcfg & GUSBCFG_PHY_LP_CLK_SEL) {
+			usbcfg &= ~GUSBCFG_PHY_LP_CLK_SEL;
+			writel(usbcfg, hsotg->regs + GUSBCFG);
+			do_reset = 1;
+		}
+	}
+
+	if (do_reset) {
+		*hprt0_modify |= HPRT0_RST;
+		queue_delayed_work(hsotg->wq_otg, &hsotg->reset_work,
+				   msecs_to_jiffies(60));
+	} else {
+		/* Port has been enabled, set the reset change flag */
+		hsotg->flags.b.port_reset_change = 1;
+	}
+}
+
+/*
+ * There are multiple conditions that can cause a port interrupt. This function
+ * determines which interrupt conditions have occurred and handles them
+ * appropriately.
+ */
+static void dwc2_port_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 hprt0;
+	u32 hprt0_modify;
+
+	dev_vdbg(hsotg->dev, "--Port Interrupt--\n");
+
+	hprt0 = readl(hsotg->regs + HPRT0);
+	hprt0_modify = hprt0;
+
+	/*
+	 * Clear appropriate bits in HPRT0 to clear the interrupt bit in
+	 * GINTSTS
+	 */
+	hprt0_modify &= ~(HPRT0_ENA | HPRT0_CONNDET | HPRT0_ENACHG |
+			  HPRT0_OVRCURRCHG);
+
+	/*
+	 * Port Connect Detected
+	 * Set flag and clear if detected
+	 */
+	if (hprt0 & HPRT0_CONNDET) {
+		dev_vdbg(hsotg->dev,
+			 "--Port Interrupt HPRT0=0x%08x Port Connect Detected--\n",
+			 hprt0);
+		hsotg->flags.b.port_connect_status_change = 1;
+		hsotg->flags.b.port_connect_status = 1;
+		hprt0_modify |= HPRT0_CONNDET;
+
+		/*
+		 * The Hub driver asserts a reset when it sees port connect
+		 * status change flag
+		 */
+	}
+
+	/*
+	 * Port Enable Changed
+	 * Clear if detected - Set internal flag if disabled
+	 */
+	if (hprt0 & HPRT0_ENACHG) {
+		dev_vdbg(hsotg->dev,
+			 "  --Port Interrupt HPRT0=0x%08x Port Enable Changed (now %d)--\n",
+			 hprt0, !!(hprt0 & HPRT0_ENA));
+		hprt0_modify |= HPRT0_ENACHG;
+		if (hprt0 & HPRT0_ENA)
+			dwc2_hprt0_enable(hsotg, hprt0, &hprt0_modify);
+		else
+			hsotg->flags.b.port_enable_change = 1;
+	}
+
+	/* Overcurrent Change Interrupt */
+	if (hprt0 & HPRT0_OVRCURRCHG) {
+		dev_vdbg(hsotg->dev,
+			 "  --Port Interrupt HPRT0=0x%08x Port Overcurrent Changed--\n",
+			 hprt0);
+		hsotg->flags.b.port_over_current_change = 1;
+		hprt0_modify |= HPRT0_OVRCURRCHG;
+	}
+
+	/* Clear Port Interrupts */
+	writel(hprt0_modify, hsotg->regs + HPRT0);
+}
+
+/*
+ * Gets the actual length of a transfer after the transfer halts. halt_status
+ * holds the reason for the halt.
+ *
+ * For IN transfers where halt_status is DWC2_HC_XFER_COMPLETE, *short_read
+ * is set to 1 upon return if less than the requested number of bytes were
+ * transferred. short_read may also be NULL on entry, in which case it remains
+ * unchanged.
+ */
+static u32 dwc2_get_actual_xfer_length(struct dwc2_hsotg *hsotg,
+				       struct dwc2_host_chan *chan, int chnum,
+				       struct dwc2_qtd *qtd,
+				       enum dwc2_halt_status halt_status,
+				       int *short_read)
+{
+	u32 hctsiz, count, length;
+
+	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
+
+	if (halt_status == DWC2_HC_XFER_COMPLETE) {
+		if (chan->ep_is_in) {
+			count = (hctsiz & TSIZ_XFERSIZE_MASK) >>
+				TSIZ_XFERSIZE_SHIFT;
+			length = chan->xfer_len - count;
+			if (short_read != NULL)
+				*short_read = (count != 0);
+		} else if (chan->qh->do_split) {
+			length = qtd->ssplit_out_xfer_count;
+		} else {
+			length = chan->xfer_len;
+		}
+	} else {
+		/*
+		 * Must use the hctsiz.pktcnt field to determine how much data
+		 * has been transferred. This field reflects the number of
+		 * packets that have been transferred via the USB. This is
+		 * always an integral number of packets if the transfer was
+		 * halted before its normal completion. (Can't use the
+		 * hctsiz.xfersize field because that reflects the number of
+		 * bytes transferred via the AHB, not the USB).
+		 */
+		count = (hctsiz & TSIZ_PKTCNT_MASK) >> TSIZ_PKTCNT_SHIFT;
+		length = (chan->start_pkt_count - count) * chan->max_packet;
+	}
+
+	return length;
+}
+
+/**
+ * dwc2_update_urb_state() - Updates the state of the URB after a Transfer
+ * Complete interrupt on the host channel. Updates the actual_length field
+ * of the URB based on the number of bytes transferred via the host channel.
+ * Sets the URB status if the data transfer is finished.
+ *
+ * Return: 1 if the data transfer specified by the URB is completely finished,
+ * 0 otherwise
+ */
+static int dwc2_update_urb_state(struct dwc2_hsotg *hsotg,
+				 struct dwc2_host_chan *chan, int chnum,
+				 struct dwc2_hcd_urb *urb,
+				 struct dwc2_qtd *qtd)
+{
+	u32 hctsiz;
+	int xfer_done = 0;
+	int short_read = 0;
+	int xfer_length = dwc2_get_actual_xfer_length(hsotg, chan, chnum, qtd,
+						      DWC2_HC_XFER_COMPLETE,
+						      &short_read);
+
+	if (urb->actual_length + xfer_length > urb->length) {
+		dev_warn(hsotg->dev, "%s(): trimming xfer length\n", __func__);
+		xfer_length = urb->length - urb->actual_length;
+	}
+
+	/* Non DWORD-aligned buffer case handling */
+	if (chan->align_buf && xfer_length && chan->ep_is_in) {
+		dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n", __func__);
+		dma_sync_single_for_cpu(hsotg->dev, urb->dma, urb->length,
+					DMA_FROM_DEVICE);
+		memcpy(urb->buf + urb->actual_length, chan->qh->dw_align_buf,
+		       xfer_length);
+		dma_sync_single_for_device(hsotg->dev, urb->dma, urb->length,
+					   DMA_FROM_DEVICE);
+	}
+
+	dev_vdbg(hsotg->dev, "urb->actual_length=%d xfer_length=%d\n",
+		 urb->actual_length, xfer_length);
+	urb->actual_length += xfer_length;
+
+	if (xfer_length && chan->ep_type == USB_ENDPOINT_XFER_BULK &&
+	    (urb->flags & URB_SEND_ZERO_PACKET) &&
+	    urb->actual_length >= urb->length &&
+	    !(urb->length % chan->max_packet)) {
+		xfer_done = 0;
+	} else if (short_read || urb->actual_length >= urb->length) {
+		xfer_done = 1;
+		urb->status = 0;
+	}
+
+	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
+	dev_vdbg(hsotg->dev, "DWC_otg: %s: %s, channel %d\n",
+		 __func__, (chan->ep_is_in ? "IN" : "OUT"), chnum);
+	dev_vdbg(hsotg->dev, "  chan->xfer_len %d\n", chan->xfer_len);
+	dev_vdbg(hsotg->dev, "  hctsiz.xfersize %d\n",
+		 (hctsiz & TSIZ_XFERSIZE_MASK) >> TSIZ_XFERSIZE_SHIFT);
+	dev_vdbg(hsotg->dev, "  urb->transfer_buffer_length %d\n", urb->length);
+	dev_vdbg(hsotg->dev, "  urb->actual_length %d\n", urb->actual_length);
+	dev_vdbg(hsotg->dev, "  short_read %d, xfer_done %d\n", short_read,
+		 xfer_done);
+
+	return xfer_done;
+}
+
+/*
+ * Save the starting data toggle for the next transfer. The data toggle is
+ * saved in the QH for non-control transfers and it's saved in the QTD for
+ * control transfers.
+ */
+void dwc2_hcd_save_data_toggle(struct dwc2_hsotg *hsotg,
+			       struct dwc2_host_chan *chan, int chnum,
+			       struct dwc2_qtd *qtd)
+{
+	u32 hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
+	u32 pid = (hctsiz & TSIZ_SC_MC_PID_MASK) >> TSIZ_SC_MC_PID_SHIFT;
+
+	if (chan->ep_type != USB_ENDPOINT_XFER_CONTROL) {
+		if (pid == TSIZ_SC_MC_PID_DATA0)
+			chan->qh->data_toggle = DWC2_HC_PID_DATA0;
+		else
+			chan->qh->data_toggle = DWC2_HC_PID_DATA1;
+	} else {
+		if (pid == TSIZ_SC_MC_PID_DATA0)
+			qtd->data_toggle = DWC2_HC_PID_DATA0;
+		else
+			qtd->data_toggle = DWC2_HC_PID_DATA1;
+	}
+}
+
+/**
+ * dwc2_update_isoc_urb_state() - Updates the state of an Isochronous URB when
+ * the transfer is stopped for any reason. The fields of the current entry in
+ * the frame descriptor array are set based on the transfer state and the input
+ * halt_status. Completes the Isochronous URB if all the URB frames have been
+ * completed.
+ *
+ * Return: DWC2_HC_XFER_COMPLETE if there are more frames remaining to be
+ * transferred in the URB. Otherwise return DWC2_HC_XFER_URB_COMPLETE.
+ */
+static enum dwc2_halt_status dwc2_update_isoc_urb_state(
+		struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan,
+		int chnum, struct dwc2_qtd *qtd,
+		enum dwc2_halt_status halt_status)
+{
+	struct dwc2_hcd_iso_packet_desc *frame_desc;
+	struct dwc2_hcd_urb *urb = qtd->urb;
+
+	if (!urb)
+		return DWC2_HC_XFER_NO_HALT_STATUS;
+
+	frame_desc = &urb->iso_descs[qtd->isoc_frame_index];
+
+	switch (halt_status) {
+	case DWC2_HC_XFER_COMPLETE:
+		frame_desc->status = 0;
+		frame_desc->actual_length = dwc2_get_actual_xfer_length(hsotg,
+					chan, chnum, qtd, halt_status, NULL);
+
+		/* Non DWORD-aligned buffer case handling */
+		if (chan->align_buf && frame_desc->actual_length &&
+		    chan->ep_is_in) {
+			dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n",
+				 __func__);
+			dma_sync_single_for_cpu(hsotg->dev, urb->dma,
+						urb->length, DMA_FROM_DEVICE);
+			memcpy(urb->buf + frame_desc->offset +
+			       qtd->isoc_split_offset, chan->qh->dw_align_buf,
+			       frame_desc->actual_length);
+			dma_sync_single_for_device(hsotg->dev, urb->dma,
+						   urb->length,
+						   DMA_FROM_DEVICE);
+		}
+		break;
+	case DWC2_HC_XFER_FRAME_OVERRUN:
+		urb->error_count++;
+		if (chan->ep_is_in)
+			frame_desc->status = -ENOSR;
+		else
+			frame_desc->status = -ECOMM;
+		frame_desc->actual_length = 0;
+		break;
+	case DWC2_HC_XFER_BABBLE_ERR:
+		urb->error_count++;
+		frame_desc->status = -EOVERFLOW;
+		/* Don't need to update actual_length in this case */
+		break;
+	case DWC2_HC_XFER_XACT_ERR:
+		urb->error_count++;
+		frame_desc->status = -EPROTO;
+		frame_desc->actual_length = dwc2_get_actual_xfer_length(hsotg,
+					chan, chnum, qtd, halt_status, NULL);
+
+		/* Non DWORD-aligned buffer case handling */
+		if (chan->align_buf && frame_desc->actual_length &&
+		    chan->ep_is_in) {
+			dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n",
+				 __func__);
+			dma_sync_single_for_cpu(hsotg->dev, urb->dma,
+						urb->length, DMA_FROM_DEVICE);
+			memcpy(urb->buf + frame_desc->offset +
+			       qtd->isoc_split_offset, chan->qh->dw_align_buf,
+			       frame_desc->actual_length);
+			dma_sync_single_for_device(hsotg->dev, urb->dma,
+						   urb->length,
+						   DMA_FROM_DEVICE);
+		}
+
+		/* Skip whole frame */
+		if (chan->qh->do_split &&
+		    chan->ep_type == USB_ENDPOINT_XFER_ISOC && chan->ep_is_in &&
+		    hsotg->core_params->dma_enable > 0) {
+			qtd->complete_split = 0;
+			qtd->isoc_split_offset = 0;
+		}
+
+		break;
+	default:
+		dev_err(hsotg->dev, "Unhandled halt_status (%d)\n",
+			halt_status);
+		break;
+	}
+
+	if (++qtd->isoc_frame_index == urb->packet_count) {
+		/*
+		 * urb->status is not used for isoc transfers. The individual
+		 * frame_desc statuses are used instead.
+		 */
+		dwc2_host_complete(hsotg, qtd, 0);
+		halt_status = DWC2_HC_XFER_URB_COMPLETE;
+	} else {
+		halt_status = DWC2_HC_XFER_COMPLETE;
+	}
+
+	return halt_status;
+}
+
+/*
+ * Frees the first QTD in the QH's list if free_qtd is 1. For non-periodic
+ * QHs, removes the QH from the active non-periodic schedule. If any QTDs are
+ * still linked to the QH, the QH is added to the end of the inactive
+ * non-periodic schedule. For periodic QHs, removes the QH from the periodic
+ * schedule if no more QTDs are linked to the QH.
+ */
+static void dwc2_deactivate_qh(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
+			       int free_qtd)
+{
+	int continue_split = 0;
+	struct dwc2_qtd *qtd;
+
+	if (dbg_qh(qh))
+		dev_vdbg(hsotg->dev, "  %s(%p,%p,%d)\n", __func__,
+			 hsotg, qh, free_qtd);
+
+	if (list_empty(&qh->qtd_list)) {
+		dev_dbg(hsotg->dev, "## QTD list empty ##\n");
+		goto no_qtd;
+	}
+
+	qtd = list_first_entry(&qh->qtd_list, struct dwc2_qtd, qtd_list_entry);
+
+	if (qtd->complete_split)
+		continue_split = 1;
+	else if (qtd->isoc_split_pos == DWC2_HCSPLT_XACTPOS_MID ||
+		 qtd->isoc_split_pos == DWC2_HCSPLT_XACTPOS_END)
+		continue_split = 1;
+
+	if (free_qtd) {
+		dwc2_hcd_qtd_unlink_and_free(hsotg, qtd, qh);
+		continue_split = 0;
+	}
+
+no_qtd:
+	if (qh->channel)
+		qh->channel->align_buf = 0;
+	qh->channel = NULL;
+	dwc2_hcd_qh_deactivate(hsotg, qh, continue_split);
+}
+
+/**
+ * dwc2_release_channel() - Releases a host channel for use by other transfers
+ *
+ * @hsotg:       The HCD state structure
+ * @chan:        The host channel to release
+ * @qtd:         The QTD associated with the host channel. This QTD may be
+ *               freed if the transfer is complete or an error has occurred.
+ * @halt_status: Reason the channel is being released. This status
+ *               determines the actions taken by this function.
+ *
+ * Also attempts to select and queue more transactions since at least one host
+ * channel is available.
+ */
+static void dwc2_release_channel(struct dwc2_hsotg *hsotg,
+				 struct dwc2_host_chan *chan,
+				 struct dwc2_qtd *qtd,
+				 enum dwc2_halt_status halt_status)
+{
+	enum dwc2_transaction_type tr_type;
+	u32 haintmsk;
+	int free_qtd = 0;
+
+	if (dbg_hc(chan))
+		dev_vdbg(hsotg->dev, "  %s: channel %d, halt_status %d\n",
+			 __func__, chan->hc_num, halt_status);
+
+	switch (halt_status) {
+	case DWC2_HC_XFER_URB_COMPLETE:
+		free_qtd = 1;
+		break;
+	case DWC2_HC_XFER_AHB_ERR:
+	case DWC2_HC_XFER_STALL:
+	case DWC2_HC_XFER_BABBLE_ERR:
+		free_qtd = 1;
+		break;
+	case DWC2_HC_XFER_XACT_ERR:
+		if (qtd && qtd->error_count >= 3) {
+			dev_vdbg(hsotg->dev,
+				 "  Complete URB with transaction error\n");
+			free_qtd = 1;
+			dwc2_host_complete(hsotg, qtd, -EPROTO);
+		}
+		break;
+	case DWC2_HC_XFER_URB_DEQUEUE:
+		/*
+		 * The QTD has already been removed and the QH has been
+		 * deactivated. Don't want to do anything except release the
+		 * host channel and try to queue more transfers.
+		 */
+		goto cleanup;
+	case DWC2_HC_XFER_PERIODIC_INCOMPLETE:
+		dev_vdbg(hsotg->dev, "  Complete URB with I/O error\n");
+		free_qtd = 1;
+		dwc2_host_complete(hsotg, qtd, -EIO);
+		break;
+	case DWC2_HC_XFER_NO_HALT_STATUS:
+	default:
+		break;
+	}
+
+	dwc2_deactivate_qh(hsotg, chan->qh, free_qtd);
+
+cleanup:
+	/*
+	 * Release the host channel for use by other transfers. The cleanup
+	 * function clears the channel interrupt enables and conditions, so
+	 * there's no need to clear the Channel Halted interrupt separately.
+	 */
+	if (!list_empty(&chan->hc_list_entry))
+		list_del(&chan->hc_list_entry);
+	dwc2_hc_cleanup(hsotg, chan);
+	list_add_tail(&chan->hc_list_entry, &hsotg->free_hc_list);
+
+	if (hsotg->core_params->uframe_sched > 0) {
+		hsotg->available_host_channels++;
+	} else {
+		switch (chan->ep_type) {
+		case USB_ENDPOINT_XFER_CONTROL:
+		case USB_ENDPOINT_XFER_BULK:
+			hsotg->non_periodic_channels--;
+			break;
+		default:
+			/*
+			 * Don't release reservations for periodic channels
+			 * here. That's done when a periodic transfer is
+			 * descheduled (i.e. when the QH is removed from the
+			 * periodic schedule).
+			 */
+			break;
+		}
+	}
+
+	haintmsk = readl(hsotg->regs + HAINTMSK);
+	haintmsk &= ~(1 << chan->hc_num);
+	writel(haintmsk, hsotg->regs + HAINTMSK);
+
+	/* Try to queue more transfers now that there's a free channel */
+	tr_type = dwc2_hcd_select_transactions(hsotg);
+	if (tr_type != DWC2_TRANSACTION_NONE)
+		dwc2_hcd_queue_transactions(hsotg, tr_type);
+}
+
+/*
+ * Halts a host channel. If the channel cannot be halted immediately because
+ * the request queue is full, this function ensures that the FIFO empty
+ * interrupt for the appropriate queue is enabled so that the halt request can
+ * be queued when there is space in the request queue.
+ *
+ * This function may also be called in DMA mode. In that case, the channel is
+ * simply released since the core always halts the channel automatically in
+ * DMA mode.
+ */
+static void dwc2_halt_channel(struct dwc2_hsotg *hsotg,
+			      struct dwc2_host_chan *chan, struct dwc2_qtd *qtd,
+			      enum dwc2_halt_status halt_status)
+{
+	if (dbg_hc(chan))
+		dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+	if (hsotg->core_params->dma_enable > 0) {
+		if (dbg_hc(chan))
+			dev_vdbg(hsotg->dev, "DMA enabled\n");
+		dwc2_release_channel(hsotg, chan, qtd, halt_status);
+		return;
+	}
+
+	/* Slave mode processing */
+	dwc2_hc_halt(hsotg, chan, halt_status);
+
+	if (chan->halt_on_queue) {
+		u32 gintmsk;
+
+		dev_vdbg(hsotg->dev, "Halt on queue\n");
+		if (chan->ep_type == USB_ENDPOINT_XFER_CONTROL ||
+		    chan->ep_type == USB_ENDPOINT_XFER_BULK) {
+			dev_vdbg(hsotg->dev, "control/bulk\n");
+			/*
+			 * Make sure the Non-periodic Tx FIFO empty interrupt
+			 * is enabled so that the non-periodic schedule will
+			 * be processed
+			 */
+			gintmsk = readl(hsotg->regs + GINTMSK);
+			gintmsk |= GINTSTS_NPTXFEMP;
+			writel(gintmsk, hsotg->regs + GINTMSK);
+		} else {
+			dev_vdbg(hsotg->dev, "isoc/intr\n");
+			/*
+			 * Move the QH from the periodic queued schedule to
+			 * the periodic assigned schedule. This allows the
+			 * halt to be queued when the periodic schedule is
+			 * processed.
+			 */
+			list_move(&chan->qh->qh_list_entry,
+				  &hsotg->periodic_sched_assigned);
+
+			/*
+			 * Make sure the Periodic Tx FIFO Empty interrupt is
+			 * enabled so that the periodic schedule will be
+			 * processed
+			 */
+			gintmsk = readl(hsotg->regs + GINTMSK);
+			gintmsk |= GINTSTS_PTXFEMP;
+			writel(gintmsk, hsotg->regs + GINTMSK);
+		}
+	}
+}
+
+/*
+ * Performs common cleanup for non-periodic transfers after a Transfer
+ * Complete interrupt. This function should be called after any endpoint type
+ * specific handling is finished to release the host channel.
+ */
+static void dwc2_complete_non_periodic_xfer(struct dwc2_hsotg *hsotg,
+					    struct dwc2_host_chan *chan,
+					    int chnum, struct dwc2_qtd *qtd,
+					    enum dwc2_halt_status halt_status)
+{
+	dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+	qtd->error_count = 0;
+
+	if (chan->hcint & HCINTMSK_NYET) {
+		/*
+		 * Got a NYET on the last transaction of the transfer. This
+		 * means that the endpoint should be in the PING state at the
+		 * beginning of the next transfer.
+		 */
+		dev_vdbg(hsotg->dev, "got NYET\n");
+		chan->qh->ping_state = 1;
+	}
+
+	/*
+	 * Always halt and release the host channel to make it available for
+	 * more transfers. There may still be more phases for a control
+	 * transfer or more data packets for a bulk transfer at this point,
+	 * but the host channel is still halted. A channel will be reassigned
+	 * to the transfer when the non-periodic schedule is processed after
+	 * the channel is released. This allows transactions to be queued
+	 * properly via dwc2_hcd_queue_transactions, which also enables the
+	 * Tx FIFO Empty interrupt if necessary.
+	 */
+	if (chan->ep_is_in) {
+		/*
+		 * IN transfers in Slave mode require an explicit disable to
+		 * halt the channel. (In DMA mode, this call simply releases
+		 * the channel.)
+		 */
+		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
+	} else {
+		/*
+		 * The channel is automatically disabled by the core for OUT
+		 * transfers in Slave mode
+		 */
+		dwc2_release_channel(hsotg, chan, qtd, halt_status);
+	}
+}
+
+/*
+ * Performs common cleanup for periodic transfers after a Transfer Complete
+ * interrupt. This function should be called after any endpoint type specific
+ * handling is finished to release the host channel.
+ */
+static void dwc2_complete_periodic_xfer(struct dwc2_hsotg *hsotg,
+					struct dwc2_host_chan *chan, int chnum,
+					struct dwc2_qtd *qtd,
+					enum dwc2_halt_status halt_status)
+{
+	u32 hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
+
+	qtd->error_count = 0;
+
+	if (!chan->ep_is_in || (hctsiz & TSIZ_PKTCNT_MASK) == 0)
+		/* Core halts channel in these cases */
+		dwc2_release_channel(hsotg, chan, qtd, halt_status);
+	else
+		/* Flush any outstanding requests from the Tx queue */
+		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
+}
+
+static int dwc2_xfercomp_isoc_split_in(struct dwc2_hsotg *hsotg,
+				       struct dwc2_host_chan *chan, int chnum,
+				       struct dwc2_qtd *qtd)
+{
+	struct dwc2_hcd_iso_packet_desc *frame_desc;
+	u32 len;
+
+	if (!qtd->urb)
+		return 0;
+
+	frame_desc = &qtd->urb->iso_descs[qtd->isoc_frame_index];
+	len = dwc2_get_actual_xfer_length(hsotg, chan, chnum, qtd,
+					  DWC2_HC_XFER_COMPLETE, NULL);
+	if (!len) {
+		qtd->complete_split = 0;
+		qtd->isoc_split_offset = 0;
+		return 0;
+	}
+
+	frame_desc->actual_length += len;
+
+	if (chan->align_buf) {
+		dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n", __func__);
+		dma_sync_single_for_cpu(hsotg->dev, qtd->urb->dma,
+					qtd->urb->length, DMA_FROM_DEVICE);
+		memcpy(qtd->urb->buf + frame_desc->offset +
+		       qtd->isoc_split_offset, chan->qh->dw_align_buf, len);
+		dma_sync_single_for_device(hsotg->dev, qtd->urb->dma,
+					   qtd->urb->length, DMA_FROM_DEVICE);
+	}
+
+	qtd->isoc_split_offset += len;
+
+	if (frame_desc->actual_length >= frame_desc->length) {
+		frame_desc->status = 0;
+		qtd->isoc_frame_index++;
+		qtd->complete_split = 0;
+		qtd->isoc_split_offset = 0;
+	}
+
+	if (qtd->isoc_frame_index == qtd->urb->packet_count) {
+		dwc2_host_complete(hsotg, qtd, 0);
+		dwc2_release_channel(hsotg, chan, qtd,
+				     DWC2_HC_XFER_URB_COMPLETE);
+	} else {
+		dwc2_release_channel(hsotg, chan, qtd,
+				     DWC2_HC_XFER_NO_HALT_STATUS);
+	}
+
+	return 1;	/* Indicates that channel released */
+}
+
+/*
+ * Handles a host channel Transfer Complete interrupt. This handler may be
+ * called in either DMA mode or Slave mode.
+ */
+static void dwc2_hc_xfercomp_intr(struct dwc2_hsotg *hsotg,
+				  struct dwc2_host_chan *chan, int chnum,
+				  struct dwc2_qtd *qtd)
+{
+	struct dwc2_hcd_urb *urb = qtd->urb;
+	int pipe_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
+	enum dwc2_halt_status halt_status = DWC2_HC_XFER_COMPLETE;
+	int urb_xfer_done;
+
+	if (dbg_hc(chan))
+		dev_vdbg(hsotg->dev,
+			 "--Host Channel %d Interrupt: Transfer Complete--\n",
+			 chnum);
+
+	if (hsotg->core_params->dma_desc_enable > 0) {
+		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum, halt_status);
+		if (pipe_type == USB_ENDPOINT_XFER_ISOC)
+			/* Do not disable the interrupt, just clear it */
+			return;
+		goto handle_xfercomp_done;
+	}
+
+	/* Handle xfer complete on CSPLIT */
+	if (chan->qh->do_split) {
+		if (chan->ep_type == USB_ENDPOINT_XFER_ISOC && chan->ep_is_in &&
+		    hsotg->core_params->dma_enable > 0) {
+			if (qtd->complete_split &&
+			    dwc2_xfercomp_isoc_split_in(hsotg, chan, chnum,
+							qtd))
+				goto handle_xfercomp_done;
+		} else {
+			qtd->complete_split = 0;
+		}
+	}
+
+	if (!urb)
+		goto handle_xfercomp_done;
+
+	/* Update the QTD and URB states */
+	switch (pipe_type) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		switch (qtd->control_phase) {
+		case DWC2_CONTROL_SETUP:
+			if (urb->length > 0)
+				qtd->control_phase = DWC2_CONTROL_DATA;
+			else
+				qtd->control_phase = DWC2_CONTROL_STATUS;
+			dev_vdbg(hsotg->dev,
+				 "  Control setup transaction done\n");
+			halt_status = DWC2_HC_XFER_COMPLETE;
+			break;
+		case DWC2_CONTROL_DATA:
+			urb_xfer_done = dwc2_update_urb_state(hsotg, chan,
+							      chnum, urb, qtd)