// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
 * hcd.c - DesignWare HS OTG Controller host-mode routines
 *
 * 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 core HCD code, and implements the Linux hc_driver
 * API
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/delay.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"

static void dwc2_port_resume(struct dwc2_hsotg *hsotg);

/*
 * =========================================================================
 *  Host Core Layer Functions
 * =========================================================================
 */

/**
 * dwc2_enable_common_interrupts() - Initializes the commmon interrupts,
 * used in both device and host modes
 *
 * @hsotg: Programming view of the DWC_otg controller
 */
static void dwc2_enable_common_interrupts(struct dwc2_hsotg *hsotg)
{
        u32 intmsk;

        /* Clear any pending OTG Interrupts */
        dwc2_writel(hsotg, 0xffffffff, GOTGINT);

        /* Clear any pending interrupts */
        dwc2_writel(hsotg, 0xffffffff, GINTSTS);

        /* Enable the interrupts in the GINTMSK */
        intmsk = GINTSTS_MODEMIS | GINTSTS_OTGINT;

        if (!hsotg->params.host_dma)
                intmsk |= GINTSTS_RXFLVL;
        if (!hsotg->params.external_id_pin_ctl)
                intmsk |= GINTSTS_CONIDSTSCHNG;

        intmsk |= GINTSTS_WKUPINT | GINTSTS_USBSUSP |
                  GINTSTS_SESSREQINT;

        if (dwc2_is_device_mode(hsotg) && hsotg->params.lpm)
                intmsk |= GINTSTS_LPMTRANRCVD;

        dwc2_writel(hsotg, intmsk, GINTMSK);
}

static int dwc2_gahbcfg_init(struct dwc2_hsotg *hsotg)
{
        u32 ahbcfg = dwc2_readl(hsotg, GAHBCFG);

        switch (hsotg->hw_params.arch) {
        case GHWCFG2_EXT_DMA_ARCH:
                dev_err(hsotg->dev, "External DMA Mode not supported\n");
                return -EINVAL;

        case GHWCFG2_INT_DMA_ARCH:
                dev_dbg(hsotg->dev, "Internal DMA Mode\n");
                if (hsotg->params.ahbcfg != -1) {
                        ahbcfg &= GAHBCFG_CTRL_MASK;
                        ahbcfg |= hsotg->params.ahbcfg &
                                  ~GAHBCFG_CTRL_MASK;
                }
                break;

        case GHWCFG2_SLAVE_ONLY_ARCH:
        default:
                dev_dbg(hsotg->dev, "Slave Only Mode\n");
                break;
        }

        if (hsotg->params.host_dma)
                ahbcfg |= GAHBCFG_DMA_EN;
        else
                hsotg->params.dma_desc_enable = false;

        dwc2_writel(hsotg, ahbcfg, GAHBCFG);

        return 0;
}

static void dwc2_gusbcfg_init(struct dwc2_hsotg *hsotg)
{
        u32 usbcfg;

        usbcfg = dwc2_readl(hsotg, GUSBCFG);
        usbcfg &= ~(GUSBCFG_HNPCAP | GUSBCFG_SRPCAP);

        switch (hsotg->hw_params.op_mode) {
        case GHWCFG2_OP_MODE_HNP_SRP_CAPABLE:
                if (hsotg->params.otg_cap ==
                                DWC2_CAP_PARAM_HNP_SRP_CAPABLE)
                        usbcfg |= GUSBCFG_HNPCAP;
                if (hsotg->params.otg_cap !=
                                DWC2_CAP_PARAM_NO_HNP_SRP_CAPABLE)
                        usbcfg |= GUSBCFG_SRPCAP;
                break;

        case GHWCFG2_OP_MODE_SRP_ONLY_CAPABLE:
        case GHWCFG2_OP_MODE_SRP_CAPABLE_DEVICE:
        case GHWCFG2_OP_MODE_SRP_CAPABLE_HOST:
                if (hsotg->params.otg_cap !=
                                DWC2_CAP_PARAM_NO_HNP_SRP_CAPABLE)
                        usbcfg |= GUSBCFG_SRPCAP;
                break;

        case GHWCFG2_OP_MODE_NO_HNP_SRP_CAPABLE:
        case GHWCFG2_OP_MODE_NO_SRP_CAPABLE_DEVICE:
        case GHWCFG2_OP_MODE_NO_SRP_CAPABLE_HOST:
        default:
                break;
        }

        dwc2_writel(hsotg, usbcfg, GUSBCFG);
}

static int dwc2_vbus_supply_init(struct dwc2_hsotg *hsotg)
{
        if (hsotg->vbus_supply)
                return regulator_enable(hsotg->vbus_supply);

        return 0;
}

static int dwc2_vbus_supply_exit(struct dwc2_hsotg *hsotg)
{
        if (hsotg->vbus_supply)
                return regulator_disable(hsotg->vbus_supply);

        return 0;
}

/**
 * dwc2_enable_host_interrupts() - Enables the Host mode interrupts
 *
 * @hsotg: Programming view of DWC_otg controller
 */
static void dwc2_enable_host_interrupts(struct dwc2_hsotg *hsotg)
{
        u32 intmsk;

        dev_dbg(hsotg->dev, "%s()\n", __func__);

        /* Disable all interrupts */
        dwc2_writel(hsotg, 0, GINTMSK);
        dwc2_writel(hsotg, 0, HAINTMSK);

        /* Enable the common interrupts */
        dwc2_enable_common_interrupts(hsotg);

        /* Enable host mode interrupts without disturbing common interrupts */
        intmsk = dwc2_readl(hsotg, GINTMSK);
        intmsk |= GINTSTS_DISCONNINT | GINTSTS_PRTINT | GINTSTS_HCHINT;
        dwc2_writel(hsotg, intmsk, GINTMSK);
}

/**
 * dwc2_disable_host_interrupts() - Disables the Host Mode interrupts
 *
 * @hsotg: Programming view of DWC_otg controller
 */
static void dwc2_disable_host_interrupts(struct dwc2_hsotg *hsotg)
{
        u32 intmsk = dwc2_readl(hsotg, GINTMSK);

        /* Disable host mode interrupts without disturbing common interrupts */
        intmsk &= ~(GINTSTS_SOF | GINTSTS_PRTINT | GINTSTS_HCHINT |
                    GINTSTS_PTXFEMP | GINTSTS_NPTXFEMP | GINTSTS_DISCONNINT);
        dwc2_writel(hsotg, intmsk, GINTMSK);
}

/*
 * dwc2_calculate_dynamic_fifo() - Calculates the default fifo size
 * For system that have a total fifo depth that is smaller than the default
 * RX + TX fifo size.
 *
 * @hsotg: Programming view of DWC_otg controller
 */
static void dwc2_calculate_dynamic_fifo(struct dwc2_hsotg *hsotg)
{
        struct dwc2_core_params *params = &hsotg->params;
        struct dwc2_hw_params *hw = &hsotg->hw_params;
        u32 rxfsiz, nptxfsiz, ptxfsiz, total_fifo_size;

        total_fifo_size = hw->total_fifo_size;
        rxfsiz = params->host_rx_fifo_size;
        nptxfsiz = params->host_nperio_tx_fifo_size;
        ptxfsiz = params->host_perio_tx_fifo_size;

        /*
         * Will use Method 2 defined in the DWC2 spec: minimum FIFO depth
         * allocation with support for high bandwidth endpoints. Synopsys
         * defines MPS(Max Packet size) for a periodic EP=1024, and for
         * non-periodic as 512.
         */
        if (total_fifo_size < (rxfsiz + nptxfsiz + ptxfsiz)) {
                /*
                 * For Buffer DMA mode/Scatter Gather DMA mode
                 * 2 * ((Largest Packet size / 4) + 1 + 1) + n
                 * with n = number of host channel.
                 * 2 * ((1024/4) + 2) = 516
                 */
                rxfsiz = 516 + hw->host_channels;

                /*
                 * min non-periodic tx fifo depth
                 * 2 * (largest non-periodic USB packet used / 4)
                 * 2 * (512/4) = 256
                 */
                nptxfsiz = 256;

                /*
                 * min periodic tx fifo depth
                 * (largest packet size*MC)/4
                 * (1024 * 3)/4 = 768
                 */
                ptxfsiz = 768;

                params->host_rx_fifo_size = rxfsiz;
                params->host_nperio_tx_fifo_size = nptxfsiz;
                params->host_perio_tx_fifo_size = ptxfsiz;
        }

        /*
         * If the summation of RX, NPTX and PTX fifo sizes is still
         * bigger than the total_fifo_size, then we have a problem.
         *
         * We won't be able to allocate as many endpoints. Right now,
         * we're just printing an error message, but ideally this FIFO
         * allocation algorithm would be improved in the future.
         *
         * FIXME improve this FIFO allocation algorithm.
         */
        if (unlikely(total_fifo_size < (rxfsiz + nptxfsiz + ptxfsiz)))
                dev_err(hsotg->dev, "invalid fifo sizes\n");
}

static void dwc2_config_fifos(struct dwc2_hsotg *hsotg)
{
        struct dwc2_core_params *params = &hsotg->params;
        u32 nptxfsiz, hptxfsiz, dfifocfg, grxfsiz;

        if (!params->enable_dynamic_fifo)
                return;

        dwc2_calculate_dynamic_fifo(hsotg);

        /* Rx FIFO */
        grxfsiz = dwc2_readl(hsotg, GRXFSIZ);
        dev_dbg(hsotg->dev, "initial grxfsiz=%08x\n", grxfsiz);
        grxfsiz &= ~GRXFSIZ_DEPTH_MASK;
        grxfsiz |= params->host_rx_fifo_size <<
                   GRXFSIZ_DEPTH_SHIFT & GRXFSIZ_DEPTH_MASK;
        dwc2_writel(hsotg, grxfsiz, GRXFSIZ);
        dev_dbg(hsotg->dev, "new grxfsiz=%08x\n",
                dwc2_readl(hsotg, GRXFSIZ));

        /* Non-periodic Tx FIFO */
        dev_dbg(hsotg->dev, "initial gnptxfsiz=%08x\n",
                dwc2_readl(hsotg, GNPTXFSIZ));
        nptxfsiz = params->host_nperio_tx_fifo_size <<
                   FIFOSIZE_DEPTH_SHIFT & FIFOSIZE_DEPTH_MASK;
        nptxfsiz |= params->host_rx_fifo_size <<
                    FIFOSIZE_STARTADDR_SHIFT & FIFOSIZE_STARTADDR_MASK;
        dwc2_writel(hsotg, nptxfsiz, GNPTXFSIZ);
        dev_dbg(hsotg->dev, "new gnptxfsiz=%08x\n",
                dwc2_readl(hsotg, GNPTXFSIZ));

        /* Periodic Tx FIFO */
        dev_dbg(hsotg->dev, "initial hptxfsiz=%08x\n",
                dwc2_readl(hsotg, HPTXFSIZ));
        hptxfsiz = params->host_perio_tx_fifo_size <<
                   FIFOSIZE_DEPTH_SHIFT & FIFOSIZE_DEPTH_MASK;
        hptxfsiz |= (params->host_rx_fifo_size +
                     params->host_nperio_tx_fifo_size) <<
                    FIFOSIZE_STARTADDR_SHIFT & FIFOSIZE_STARTADDR_MASK;
        dwc2_writel(hsotg, hptxfsiz, HPTXFSIZ);
        dev_dbg(hsotg->dev, "new hptxfsiz=%08x\n",
                dwc2_readl(hsotg, HPTXFSIZ));

        if (hsotg->params.en_multiple_tx_fifo &&
            hsotg->hw_params.snpsid >= DWC2_CORE_REV_2_91a) {
                /*
                 * This feature was implemented in 2.91a version
                 * Global DFIFOCFG calculation for Host mode -
                 * include RxFIFO, NPTXFIFO and HPTXFIFO
                 */
                dfifocfg = dwc2_readl(hsotg, GDFIFOCFG);
                dfifocfg &= ~GDFIFOCFG_EPINFOBASE_MASK;
                dfifocfg |= (params->host_rx_fifo_size +
                             params->host_nperio_tx_fifo_size +
                             params->host_perio_tx_fifo_size) <<
                            GDFIFOCFG_EPINFOBASE_SHIFT &
                            GDFIFOCFG_EPINFOBASE_MASK;
                dwc2_writel(hsotg, dfifocfg, GDFIFOCFG);
        }
}

/**
 * dwc2_calc_frame_interval() - Calculates the correct frame Interval value for
 * the HFIR register according to PHY type and speed
 *
 * @hsotg: Programming view of DWC_otg controller
 *
 * NOTE: The caller can modify the value of the HFIR register only after the
 * Port Enable bit of the Host Port Control and Status register (HPRT.EnaPort)
 * has been set
 */
u32 dwc2_calc_frame_interval(struct dwc2_hsotg *hsotg)
{
        u32 usbcfg;
        u32 hprt0;
        int clock = 60; /* default value */

        usbcfg = dwc2_readl(hsotg, GUSBCFG);
        hprt0 = dwc2_readl(hsotg, HPRT0);

        if (!(usbcfg & GUSBCFG_PHYSEL) && (usbcfg & GUSBCFG_ULPI_UTMI_SEL) &&
            !(usbcfg & GUSBCFG_PHYIF16))
                clock = 60;
        if ((usbcfg & GUSBCFG_PHYSEL) && hsotg->hw_params.fs_phy_type ==
            GHWCFG2_FS_PHY_TYPE_SHARED_ULPI)
                clock = 48;
        if (!(usbcfg & GUSBCFG_PHY_LP_CLK_SEL) && !(usbcfg & GUSBCFG_PHYSEL) &&
            !(usbcfg & GUSBCFG_ULPI_UTMI_SEL) && (usbcfg & GUSBCFG_PHYIF16))
                clock = 30;
        if (!(usbcfg & GUSBCFG_PHY_LP_CLK_SEL) && !(usbcfg & GUSBCFG_PHYSEL) &&
            !(usbcfg & GUSBCFG_ULPI_UTMI_SEL) && !(usbcfg & GUSBCFG_PHYIF16))
                clock = 60;
        if ((usbcfg & GUSBCFG_PHY_LP_CLK_SEL) && !(usbcfg & GUSBCFG_PHYSEL) &&
            !(usbcfg & GUSBCFG_ULPI_UTMI_SEL) && (usbcfg & GUSBCFG_PHYIF16))
                clock = 48;
        if ((usbcfg & GUSBCFG_PHYSEL) && !(usbcfg & GUSBCFG_PHYIF16) &&
            hsotg->hw_params.fs_phy_type == GHWCFG2_FS_PHY_TYPE_SHARED_UTMI)
                clock = 48;
        if ((usbcfg & GUSBCFG_PHYSEL) &&
            hsotg->hw_params.fs_phy_type == GHWCFG2_FS_PHY_TYPE_DEDICATED)
                clock = 48;

        if ((hprt0 & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT == HPRT0_SPD_HIGH_SPEED)
                /* High speed case */
                return 125 * clock - 1;

        /* FS/LS case */
        return 1000 * clock - 1;
}

/**
 * dwc2_read_packet() - Reads a packet from the Rx FIFO into the destination
 * buffer
 *
 * @hsotg: Programming view of DWC_otg controller
 * @dest:    Destination buffer for the packet
 * @bytes:   Number of bytes to copy to the destination
 */
void dwc2_read_packet(struct dwc2_hsotg *hsotg, u8 *dest, u16 bytes)
{
        u32 *data_buf = (u32 *)dest;
        int word_count = (bytes + 3) / 4;
        int i;

        /*
         * Todo: Account for the case where dest is not dword aligned. This
         * requires reading data from the FIFO into a u32 temp buffer, then
         * moving it into the data buffer.
         */

        dev_vdbg(hsotg->dev, "%s(%p,%p,%d)\n", __func__, hsotg, dest, bytes);

        for (i = 0; i < word_count; i++, data_buf++)
                *data_buf = dwc2_readl(hsotg, HCFIFO(0));
}

/**
 * dwc2_dump_channel_info() - Prints the state of a host channel
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Pointer to the channel to dump
 *
 * Must be called with interrupt disabled and spinlock held
 *
 * NOTE: This function will be removed once the peripheral controller code
 * is integrated and the driver is stable
 */
static void dwc2_dump_channel_info(struct dwc2_hsotg *hsotg,
                                   struct dwc2_host_chan *chan)
{
#ifdef VERBOSE_DEBUG
        int num_channels = hsotg->params.host_channels;
        struct dwc2_qh *qh;
        u32 hcchar;
        u32 hcsplt;
        u32 hctsiz;
        u32 hc_dma;
        int i;

        if (!chan)
                return;

        hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));
        hcsplt = dwc2_readl(hsotg, HCSPLT(chan->hc_num));
        hctsiz = dwc2_readl(hsotg, HCTSIZ(chan->hc_num));
        hc_dma = dwc2_readl(hsotg, HCDMA(chan->hc_num));

        dev_dbg(hsotg->dev, "  Assigned to channel %p:\n", chan);
        dev_dbg(hsotg->dev, "    hcchar 0x%08x, hcsplt 0x%08x\n",
                hcchar, hcsplt);
        dev_dbg(hsotg->dev, "    hctsiz 0x%08x, hc_dma 0x%08x\n",
                hctsiz, hc_dma);
        dev_dbg(hsotg->dev, "    dev_addr: %d, ep_num: %d, ep_is_in: %d\n",
                chan->dev_addr, chan->ep_num, chan->ep_is_in);
        dev_dbg(hsotg->dev, "    ep_type: %d\n", chan->ep_type);
        dev_dbg(hsotg->dev, "    max_packet: %d\n", chan->max_packet);
        dev_dbg(hsotg->dev, "    data_pid_start: %d\n", chan->data_pid_start);
        dev_dbg(hsotg->dev, "    xfer_started: %d\n", chan->xfer_started);
        dev_dbg(hsotg->dev, "    halt_status: %d\n", chan->halt_status);
        dev_dbg(hsotg->dev, "    xfer_buf: %p\n", chan->xfer_buf);
        dev_dbg(hsotg->dev, "    xfer_dma: %08lx\n",
                (unsigned long)chan->xfer_dma);
        dev_dbg(hsotg->dev, "    xfer_len: %d\n", chan->xfer_len);
        dev_dbg(hsotg->dev, "    qh: %p\n", chan->qh);
        dev_dbg(hsotg->dev, "  NP inactive sched:\n");
        list_for_each_entry(qh, &hsotg->non_periodic_sched_inactive,
                            qh_list_entry)
                dev_dbg(hsotg->dev, "    %p\n", qh);
        dev_dbg(hsotg->dev, "  NP waiting sched:\n");
        list_for_each_entry(qh, &hsotg->non_periodic_sched_waiting,
                            qh_list_entry)
                dev_dbg(hsotg->dev, "    %p\n", qh);
        dev_dbg(hsotg->dev, "  NP active sched:\n");
        list_for_each_entry(qh, &hsotg->non_periodic_sched_active,
                            qh_list_entry)
                dev_dbg(hsotg->dev, "    %p\n", qh);
        dev_dbg(hsotg->dev, "  Channels:\n");
        for (i = 0; i < num_channels; i++) {
                struct dwc2_host_chan *chan = hsotg->hc_ptr_array[i];

                dev_dbg(hsotg->dev, "    %2d: %p\n", i, chan);
        }
#endif /* VERBOSE_DEBUG */
}

static int _dwc2_hcd_start(struct usb_hcd *hcd);

static void dwc2_host_start(struct dwc2_hsotg *hsotg)
{
        struct usb_hcd *hcd = dwc2_hsotg_to_hcd(hsotg);

        hcd->self.is_b_host = dwc2_hcd_is_b_host(hsotg);
        _dwc2_hcd_start(hcd);
}

static void dwc2_host_disconnect(struct dwc2_hsotg *hsotg)
{
        struct usb_hcd *hcd = dwc2_hsotg_to_hcd(hsotg);

        hcd->self.is_b_host = 0;
}

static void dwc2_host_hub_info(struct dwc2_hsotg *hsotg, void *context,
                               int *hub_addr, int *hub_port)
{
        struct urb *urb = context;

        if (urb->dev->tt)
                *hub_addr = urb->dev->tt->hub->devnum;
        else
                *hub_addr = 0;
        *hub_port = urb->dev->ttport;
}

/*
 * =========================================================================
 *  Low Level Host Channel Access Functions
 * =========================================================================
 */

static void dwc2_hc_enable_slave_ints(struct dwc2_hsotg *hsotg,
                                      struct dwc2_host_chan *chan)
{
        u32 hcintmsk = HCINTMSK_CHHLTD;

        switch (chan->ep_type) {
        case USB_ENDPOINT_XFER_CONTROL:
        case USB_ENDPOINT_XFER_BULK:
                dev_vdbg(hsotg->dev, "control/bulk\n");
                hcintmsk |= HCINTMSK_XFERCOMPL;
                hcintmsk |= HCINTMSK_STALL;
                hcintmsk |= HCINTMSK_XACTERR;
                hcintmsk |= HCINTMSK_DATATGLERR;
                if (chan->ep_is_in) {
                        hcintmsk |= HCINTMSK_BBLERR;
                } else {
                        hcintmsk |= HCINTMSK_NAK;
                        hcintmsk |= HCINTMSK_NYET;
                        if (chan->do_ping)
                                hcintmsk |= HCINTMSK_ACK;
                }

                if (chan->do_split) {
                        hcintmsk |= HCINTMSK_NAK;
                        if (chan->complete_split)
                                hcintmsk |= HCINTMSK_NYET;
                        else
                                hcintmsk |= HCINTMSK_ACK;
                }

                if (chan->error_state)
                        hcintmsk |= HCINTMSK_ACK;
                break;

        case USB_ENDPOINT_XFER_INT:
                if (dbg_perio())
                        dev_vdbg(hsotg->dev, "intr\n");
                hcintmsk |= HCINTMSK_XFERCOMPL;
                hcintmsk |= HCINTMSK_NAK;
                hcintmsk |= HCINTMSK_STALL;
                hcintmsk |= HCINTMSK_XACTERR;
                hcintmsk |= HCINTMSK_DATATGLERR;
                hcintmsk |= HCINTMSK_FRMOVRUN;

                if (chan->ep_is_in)
                        hcintmsk |= HCINTMSK_BBLERR;
                if (chan->error_state)
                        hcintmsk |= HCINTMSK_ACK;
                if (chan->do_split) {
                        if (chan->complete_split)
                                hcintmsk |= HCINTMSK_NYET;
                        else
                                hcintmsk |= HCINTMSK_ACK;
                }
                break;

        case USB_ENDPOINT_XFER_ISOC:
                if (dbg_perio())
                        dev_vdbg(hsotg->dev, "isoc\n");
                hcintmsk |= HCINTMSK_XFERCOMPL;
                hcintmsk |= HCINTMSK_FRMOVRUN;
                hcintmsk |= HCINTMSK_ACK;

                if (chan->ep_is_in) {
                        hcintmsk |= HCINTMSK_XACTERR;
                        hcintmsk |= HCINTMSK_BBLERR;
                }
                break;
        default:
                dev_err(hsotg->dev, "## Unknown EP type ##\n");
                break;
        }

        dwc2_writel(hsotg, hcintmsk, HCINTMSK(chan->hc_num));
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "set HCINTMSK to %08x\n", hcintmsk);
}

static void dwc2_hc_enable_dma_ints(struct dwc2_hsotg *hsotg,
                                    struct dwc2_host_chan *chan)
{
        u32 hcintmsk = HCINTMSK_CHHLTD;

        /*
         * For Descriptor DMA mode core halts the channel on AHB error.
         * Interrupt is not required.
         */
        if (!hsotg->params.dma_desc_enable) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "desc DMA disabled\n");
                hcintmsk |= HCINTMSK_AHBERR;
        } else {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "desc DMA enabled\n");
                if (chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                        hcintmsk |= HCINTMSK_XFERCOMPL;
        }

        if (chan->error_state && !chan->do_split &&
            chan->ep_type != USB_ENDPOINT_XFER_ISOC) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "setting ACK\n");
                hcintmsk |= HCINTMSK_ACK;
                if (chan->ep_is_in) {
                        hcintmsk |= HCINTMSK_DATATGLERR;
                        if (chan->ep_type != USB_ENDPOINT_XFER_INT)
                                hcintmsk |= HCINTMSK_NAK;
                }
        }

        dwc2_writel(hsotg, hcintmsk, HCINTMSK(chan->hc_num));
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "set HCINTMSK to %08x\n", hcintmsk);
}

static void dwc2_hc_enable_ints(struct dwc2_hsotg *hsotg,
                                struct dwc2_host_chan *chan)
{
        u32 intmsk;

        if (hsotg->params.host_dma) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "DMA enabled\n");
                dwc2_hc_enable_dma_ints(hsotg, chan);
        } else {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "DMA disabled\n");
                dwc2_hc_enable_slave_ints(hsotg, chan);
        }

        /* Enable the top level host channel interrupt */
        intmsk = dwc2_readl(hsotg, HAINTMSK);
        intmsk |= 1 << chan->hc_num;
        dwc2_writel(hsotg, intmsk, HAINTMSK);
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "set HAINTMSK to %08x\n", intmsk);

        /* Make sure host channel interrupts are enabled */
        intmsk = dwc2_readl(hsotg, GINTMSK);
        intmsk |= GINTSTS_HCHINT;
        dwc2_writel(hsotg, intmsk, GINTMSK);
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "set GINTMSK to %08x\n", intmsk);
}

/**
 * dwc2_hc_init() - Prepares a host channel for transferring packets to/from
 * a specific endpoint
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel
 *
 * The HCCHARn register is set up with the characteristics specified in chan.
 * Host channel interrupts that may need to be serviced while this transfer is
 * in progress are enabled.
 */
static void dwc2_hc_init(struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan)
{
        u8 hc_num = chan->hc_num;
        u32 hcintmsk;
        u32 hcchar;
        u32 hcsplt = 0;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        /* Clear old interrupt conditions for this host channel */
        hcintmsk = 0xffffffff;
        hcintmsk &= ~HCINTMSK_RESERVED14_31;
        dwc2_writel(hsotg, hcintmsk, HCINT(hc_num));

        /* Enable channel interrupts required for this transfer */
        dwc2_hc_enable_ints(hsotg, chan);

        /*
         * Program the HCCHARn register with the endpoint characteristics for
         * the current transfer
         */
        hcchar = chan->dev_addr << HCCHAR_DEVADDR_SHIFT & HCCHAR_DEVADDR_MASK;
        hcchar |= chan->ep_num << HCCHAR_EPNUM_SHIFT & HCCHAR_EPNUM_MASK;
        if (chan->ep_is_in)
                hcchar |= HCCHAR_EPDIR;
        if (chan->speed == USB_SPEED_LOW)
                hcchar |= HCCHAR_LSPDDEV;
        hcchar |= chan->ep_type << HCCHAR_EPTYPE_SHIFT & HCCHAR_EPTYPE_MASK;
        hcchar |= chan->max_packet << HCCHAR_MPS_SHIFT & HCCHAR_MPS_MASK;
        dwc2_writel(hsotg, hcchar, HCCHAR(hc_num));
        if (dbg_hc(chan)) {
                dev_vdbg(hsotg->dev, "set HCCHAR(%d) to %08x\n",
                         hc_num, hcchar);

                dev_vdbg(hsotg->dev, "%s: Channel %d\n",
                         __func__, hc_num);
                dev_vdbg(hsotg->dev, "   Dev Addr: %d\n",
                         chan->dev_addr);
                dev_vdbg(hsotg->dev, "   Ep Num: %d\n",
                         chan->ep_num);
                dev_vdbg(hsotg->dev, "   Is In: %d\n",
                         chan->ep_is_in);
                dev_vdbg(hsotg->dev, "   Is Low Speed: %d\n",
                         chan->speed == USB_SPEED_LOW);
                dev_vdbg(hsotg->dev, "   Ep Type: %d\n",
                         chan->ep_type);
                dev_vdbg(hsotg->dev, "   Max Pkt: %d\n",
                         chan->max_packet);
        }

        /* Program the HCSPLT register for SPLITs */
        if (chan->do_split) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev,
                                 "Programming HC %d with split --> %s\n",
                                 hc_num,
                                 chan->complete_split ? "CSPLIT" : "SSPLIT");
                if (chan->complete_split)
                        hcsplt |= HCSPLT_COMPSPLT;
                hcsplt |= chan->xact_pos << HCSPLT_XACTPOS_SHIFT &
                          HCSPLT_XACTPOS_MASK;
                hcsplt |= chan->hub_addr << HCSPLT_HUBADDR_SHIFT &
                          HCSPLT_HUBADDR_MASK;
                hcsplt |= chan->hub_port << HCSPLT_PRTADDR_SHIFT &
                          HCSPLT_PRTADDR_MASK;
                if (dbg_hc(chan)) {
                        dev_vdbg(hsotg->dev, "    comp split %d\n",
                                 chan->complete_split);
                        dev_vdbg(hsotg->dev, "    xact pos %d\n",
                                 chan->xact_pos);
                        dev_vdbg(hsotg->dev, "    hub addr %d\n",
                                 chan->hub_addr);
                        dev_vdbg(hsotg->dev, "    hub port %d\n",
                                 chan->hub_port);
                        dev_vdbg(hsotg->dev, "    is_in %d\n",
                                 chan->ep_is_in);
                        dev_vdbg(hsotg->dev, "    Max Pkt %d\n",
                                 chan->max_packet);
                        dev_vdbg(hsotg->dev, "    xferlen %d\n",
                                 chan->xfer_len);
                }
        }

        dwc2_writel(hsotg, hcsplt, HCSPLT(hc_num));
}

/**
 * dwc2_hc_halt() - Attempts to halt a host channel
 *
 * @hsotg:       Controller register interface
 * @chan:        Host channel to halt
 * @halt_status: Reason for halting the channel
 *
 * This function should only be called in Slave mode or to abort a transfer in
 * either Slave mode or DMA mode. Under normal circumstances in DMA mode, the
 * controller halts the channel when the transfer is complete or a condition
 * occurs that requires application intervention.
 *
 * In slave mode, checks for a free request queue entry, then sets the Channel
 * Enable and Channel Disable bits of the Host Channel Characteristics
 * register of the specified channel to intiate the halt. If there is no free
 * request queue entry, sets only the Channel Disable bit of the HCCHARn
 * register to flush requests for this channel. In the latter case, sets a
 * flag to indicate that the host channel needs to be halted when a request
 * queue slot is open.
 *
 * In DMA mode, always sets the Channel Enable and Channel Disable bits of the
 * HCCHARn register. The controller ensures there is space in the request
 * queue before submitting the halt request.
 *
 * Some time may elapse before the core flushes any posted requests for this
 * host channel and halts. The Channel Halted interrupt handler completes the
 * deactivation of the host channel.
 */
void dwc2_hc_halt(struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan,
                  enum dwc2_halt_status halt_status)
{
        u32 nptxsts, hptxsts, hcchar;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        /*
         * In buffer DMA or external DMA mode channel can't be halted
         * for non-split periodic channels. At the end of the next
         * uframe/frame (in the worst case), the core generates a channel
         * halted and disables the channel automatically.
         */
        if ((hsotg->params.g_dma && !hsotg->params.g_dma_desc) ||
            hsotg->hw_params.arch == GHWCFG2_EXT_DMA_ARCH) {
                if (!chan->do_split &&
                    (chan->ep_type == USB_ENDPOINT_XFER_ISOC ||
                     chan->ep_type == USB_ENDPOINT_XFER_INT)) {
                        dev_err(hsotg->dev, "%s() Channel can't be halted\n",
                                __func__);
                        return;
                }
        }

        if (halt_status == DWC2_HC_XFER_NO_HALT_STATUS)
                dev_err(hsotg->dev, "!!! halt_status = %d !!!\n", halt_status);

        if (halt_status == DWC2_HC_XFER_URB_DEQUEUE ||
            halt_status == DWC2_HC_XFER_AHB_ERR) {
                /*
                 * Disable all channel interrupts except Ch Halted. The QTD
                 * and QH state associated with this transfer has been cleared
                 * (in the case of URB_DEQUEUE), so the channel needs to be
                 * shut down carefully to prevent crashes.
                 */
                u32 hcintmsk = HCINTMSK_CHHLTD;

                dev_vdbg(hsotg->dev, "dequeue/error\n");
                dwc2_writel(hsotg, hcintmsk, HCINTMSK(chan->hc_num));

                /*
                 * Make sure no other interrupts besides halt are currently
                 * pending. Handling another interrupt could cause a crash due
                 * to the QTD and QH state.
                 */
                dwc2_writel(hsotg, ~hcintmsk, HCINT(chan->hc_num));

                /*
                 * Make sure the halt status is set to URB_DEQUEUE or AHB_ERR
                 * even if the channel was already halted for some other
                 * reason
                 */
                chan->halt_status = halt_status;

                hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));
                if (!(hcchar & HCCHAR_CHENA)) {
                        /*
                         * The channel is either already halted or it hasn't
                         * started yet. In DMA mode, the transfer may halt if
                         * it finishes normally or a condition occurs that
                         * requires driver intervention. Don't want to halt
                         * the channel again. In either Slave or DMA mode,
                         * it's possible that the transfer has been assigned
                         * to a channel, but not started yet when an URB is
                         * dequeued. Don't want to halt a channel that hasn't
                         * started yet.
                         */
                        return;
                }
        }
        if (chan->halt_pending) {
                /*
                 * A halt has already been issued for this channel. This might
                 * happen when a transfer is aborted by a higher level in
                 * the stack.
                 */
                dev_vdbg(hsotg->dev,
                         "*** %s: Channel %d, chan->halt_pending already set ***\n",
                         __func__, chan->hc_num);
                return;
        }

        hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));

        /* No need to set the bit in DDMA for disabling the channel */
        /* TODO check it everywhere channel is disabled */
        if (!hsotg->params.dma_desc_enable) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "desc DMA disabled\n");
                hcchar |= HCCHAR_CHENA;
        } else {
                if (dbg_hc(chan))
                        dev_dbg(hsotg->dev, "desc DMA enabled\n");
        }
        hcchar |= HCCHAR_CHDIS;

        if (!hsotg->params.host_dma) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "DMA not enabled\n");
                hcchar |= HCCHAR_CHENA;

                /* Check for space in the request queue to issue the halt */
                if (chan->ep_type == USB_ENDPOINT_XFER_CONTROL ||
                    chan->ep_type == USB_ENDPOINT_XFER_BULK) {
                        dev_vdbg(hsotg->dev, "control/bulk\n");
                        nptxsts = dwc2_readl(hsotg, GNPTXSTS);
                        if ((nptxsts & TXSTS_QSPCAVAIL_MASK) == 0) {
                                dev_vdbg(hsotg->dev, "Disabling channel\n");
                                hcchar &= ~HCCHAR_CHENA;
                        }
                } else {
                        if (dbg_perio())
                                dev_vdbg(hsotg->dev, "isoc/intr\n");
                        hptxsts = dwc2_readl(hsotg, HPTXSTS);
                        if ((hptxsts & TXSTS_QSPCAVAIL_MASK) == 0 ||
                            hsotg->queuing_high_bandwidth) {
                                if (dbg_perio())
                                        dev_vdbg(hsotg->dev, "Disabling channel\n");
                                hcchar &= ~HCCHAR_CHENA;
                        }
                }
        } else {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "DMA enabled\n");
        }

        dwc2_writel(hsotg, hcchar, HCCHAR(chan->hc_num));
        chan->halt_status = halt_status;

        if (hcchar & HCCHAR_CHENA) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "Channel enabled\n");
                chan->halt_pending = 1;
                chan->halt_on_queue = 0;
        } else {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "Channel disabled\n");
                chan->halt_on_queue = 1;
        }

        if (dbg_hc(chan)) {
                dev_vdbg(hsotg->dev, "%s: Channel %d\n", __func__,
                         chan->hc_num);
                dev_vdbg(hsotg->dev, "   hcchar: 0x%08x\n",
                         hcchar);
                dev_vdbg(hsotg->dev, "   halt_pending: %d\n",
                         chan->halt_pending);
                dev_vdbg(hsotg->dev, "   halt_on_queue: %d\n",
                         chan->halt_on_queue);
                dev_vdbg(hsotg->dev, "   halt_status: %d\n",
                         chan->halt_status);
        }
}

/**
 * dwc2_hc_cleanup() - Clears the transfer state for a host channel
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Identifies the host channel to clean up
 *
 * This function is normally called after a transfer is done and the host
 * channel is being released
 */
void dwc2_hc_cleanup(struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan)
{
        u32 hcintmsk;

        chan->xfer_started = 0;

        list_del_init(&chan->split_order_list_entry);

        /*
         * Clear channel interrupt enables and any unhandled channel interrupt
         * conditions
         */
        dwc2_writel(hsotg, 0, HCINTMSK(chan->hc_num));
        hcintmsk = 0xffffffff;
        hcintmsk &= ~HCINTMSK_RESERVED14_31;
        dwc2_writel(hsotg, hcintmsk, HCINT(chan->hc_num));
}

/**
 * dwc2_hc_set_even_odd_frame() - Sets the channel property that indicates in
 * which frame a periodic transfer should occur
 *
 * @hsotg:  Programming view of DWC_otg controller
 * @chan:   Identifies the host channel to set up and its properties
 * @hcchar: Current value of the HCCHAR register for the specified host channel
 *
 * This function has no effect on non-periodic transfers
 */
static void dwc2_hc_set_even_odd_frame(struct dwc2_hsotg *hsotg,
                                       struct dwc2_host_chan *chan, u32 *hcchar)
{
        if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
            chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
                int host_speed;
                int xfer_ns;
                int xfer_us;

                int bytes_in_fifo;
                u16 fifo_space;
                u16 frame_number;
                u16 wire_frame;

                /*
                 * Try to figure out if we're an even or odd frame. If we set
                 * even and the current frame number is even the the transfer
                 * will happen immediately.  Similar if both are odd. If one is
                 * even and the other is odd then the transfer will happen when
                 * the frame number ticks.
                 *
                 * There's a bit of a balancing act to get this right.
                 * Sometimes we may want to send data in the current frame (AK
                 * right away).  We might want to do this if the frame number
                 * _just_ ticked, but we might also want to do this in order
                 * to continue a split transaction that happened late in a
                 * microframe (so we didn't know to queue the next transfer
                 * until the frame number had ticked).  The problem is that we
                 * need a lot of knowledge to know if there's actually still
                 * time to send things or if it would be better to wait until
                 * the next frame.
                 *
                 * We can look at how much time is left in the current frame
                 * and make a guess about whether we'll have time to transfer.
                 * We'll do that.
                 */

                /* Get speed host is running at */
                host_speed = (chan->speed != USB_SPEED_HIGH &&
                              !chan->do_split) ? chan->speed : USB_SPEED_HIGH;

                /* See how many bytes are in the periodic FIFO right now */
                fifo_space = (dwc2_readl(hsotg, HPTXSTS) &
                              TXSTS_FSPCAVAIL_MASK) >> TXSTS_FSPCAVAIL_SHIFT;
                bytes_in_fifo = sizeof(u32) *
                                (hsotg->params.host_perio_tx_fifo_size -
                                 fifo_space);

                /*
                 * Roughly estimate bus time for everything in the periodic
                 * queue + our new transfer.  This is "rough" because we're
                 * using a function that makes takes into account IN/OUT
                 * and INT/ISO and we're just slamming in one value for all
                 * transfers.  This should be an over-estimate and that should
                 * be OK, but we can probably tighten it.
                 */
                xfer_ns = usb_calc_bus_time(host_speed, false, false,
                                            chan->xfer_len + bytes_in_fifo);
                xfer_us = NS_TO_US(xfer_ns);

                /* See what frame number we'll be at by the time we finish */
                frame_number = dwc2_hcd_get_future_frame_number(hsotg, xfer_us);

                /* This is when we were scheduled to be on the wire */
                wire_frame = dwc2_frame_num_inc(chan->qh->next_active_frame, 1);

                /*
                 * If we'd finish _after_ the frame we're scheduled in then
                 * it's hopeless.  Just schedule right away and hope for the
                 * best.  Note that it _might_ be wise to call back into the
                 * scheduler to pick a better frame, but this is better than
                 * nothing.
                 */
                if (dwc2_frame_num_gt(frame_number, wire_frame)) {
                        dwc2_sch_vdbg(hsotg,
                                      "QH=%p EO MISS fr=%04x=>%04x (%+d)\n",
                                      chan->qh, wire_frame, frame_number,
                                      dwc2_frame_num_dec(frame_number,
                                                         wire_frame));
                        wire_frame = frame_number;

                        /*
                         * We picked a different frame number; communicate this
                         * back to the scheduler so it doesn't try to schedule
                         * another in the same frame.
                         *
                         * Remember that next_active_frame is 1 before the wire
                         * frame.
                         */
                        chan->qh->next_active_frame =
                                dwc2_frame_num_dec(frame_number, 1);
                }

                if (wire_frame & 1)
                        *hcchar |= HCCHAR_ODDFRM;
                else
                        *hcchar &= ~HCCHAR_ODDFRM;
        }
}

static void dwc2_set_pid_isoc(struct dwc2_host_chan *chan)
{
        /* Set up the initial PID for the transfer */
        if (chan->speed == USB_SPEED_HIGH) {
                if (chan->ep_is_in) {
                        if (chan->multi_count == 1)
                                chan->data_pid_start = DWC2_HC_PID_DATA0;
                        else if (chan->multi_count == 2)
                                chan->data_pid_start = DWC2_HC_PID_DATA1;
                        else
                                chan->data_pid_start = DWC2_HC_PID_DATA2;
                } else {
                        if (chan->multi_count == 1)
                                chan->data_pid_start = DWC2_HC_PID_DATA0;
                        else
                                chan->data_pid_start = DWC2_HC_PID_MDATA;
                }
        } else {
                chan->data_pid_start = DWC2_HC_PID_DATA0;
        }
}

/**
 * dwc2_hc_write_packet() - Writes a packet into the Tx FIFO associated with
 * the Host Channel
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel
 *
 * This function should only be called in Slave mode. For a channel associated
 * with a non-periodic EP, the non-periodic Tx FIFO is written. For a channel
 * associated with a periodic EP, the periodic Tx FIFO is written.
 *
 * Upon return the xfer_buf and xfer_count fields in chan are incremented by
 * the number of bytes written to the Tx FIFO.
 */
static void dwc2_hc_write_packet(struct dwc2_hsotg *hsotg,
                                 struct dwc2_host_chan *chan)
{
        u32 i;
        u32 remaining_count;
        u32 byte_count;
        u32 dword_count;
        u32 *data_buf = (u32 *)chan->xfer_buf;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        remaining_count = chan->xfer_len - chan->xfer_count;
        if (remaining_count > chan->max_packet)
                byte_count = chan->max_packet;
        else
                byte_count = remaining_count;

        dword_count = (byte_count + 3) / 4;

        if (((unsigned long)data_buf & 0x3) == 0) {
                /* xfer_buf is DWORD aligned */
                for (i = 0; i < dword_count; i++, data_buf++)
                        dwc2_writel(hsotg, *data_buf, HCFIFO(chan->hc_num));
        } else {
                /* xfer_buf is not DWORD aligned */
                for (i = 0; i < dword_count; i++, data_buf++) {
                        u32 data = data_buf[0] | data_buf[1] << 8 |
                                   data_buf[2] << 16 | data_buf[3] << 24;
                        dwc2_writel(hsotg, data, HCFIFO(chan->hc_num));
                }
        }

        chan->xfer_count += byte_count;
        chan->xfer_buf += byte_count;
}

/**
 * dwc2_hc_do_ping() - Starts a PING transfer
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel
 *
 * This function should only be called in Slave mode. The Do Ping bit is set in
 * the HCTSIZ register, then the channel is enabled.
 */
static void dwc2_hc_do_ping(struct dwc2_hsotg *hsotg,
                            struct dwc2_host_chan *chan)
{
        u32 hcchar;
        u32 hctsiz;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s: Channel %d\n", __func__,
                         chan->hc_num);

        hctsiz = TSIZ_DOPNG;
        hctsiz |= 1 << TSIZ_PKTCNT_SHIFT;
        dwc2_writel(hsotg, hctsiz, HCTSIZ(chan->hc_num));

        hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));
        hcchar |= HCCHAR_CHENA;
        hcchar &= ~HCCHAR_CHDIS;
        dwc2_writel(hsotg, hcchar, HCCHAR(chan->hc_num));
}

/**
 * dwc2_hc_start_transfer() - Does the setup for a data transfer for a host
 * channel and starts the transfer
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel. The xfer_len value
 *         may be reduced to accommodate the max widths of the XferSize and
 *         PktCnt fields in the HCTSIZn register. The multi_count value may be
 *         changed to reflect the final xfer_len value.
 *
 * This function may be called in either Slave mode or DMA mode. In Slave mode,
 * the caller must ensure that there is sufficient space in the request queue
 * and Tx Data FIFO.
 *
 * For an OUT transfer in Slave mode, it loads a data packet into the
 * appropriate FIFO. If necessary, additional data packets are loaded in the
 * Host ISR.
 *
 * For an IN transfer in Slave mode, a data packet is requested. The data
 * packets are unloaded from the Rx FIFO in the Host ISR. If necessary,
 * additional data packets are requested in the Host ISR.
 *
 * For a PING transfer in Slave mode, the Do Ping bit is set in the HCTSIZ
 * register along with a packet count of 1 and the channel is enabled. This
 * causes a single PING transaction to occur. Other fields in HCTSIZ are
 * simply set to 0 since no data transfer occurs in this case.
 *
 * For a PING transfer in DMA mode, the HCTSIZ register is initialized with
 * all the information required to perform the subsequent data transfer. In
 * addition, the Do Ping bit is set in the HCTSIZ register. In this case, the
 * controller performs the entire PING protocol, then starts the data
 * transfer.
 */
static void dwc2_hc_start_transfer(struct dwc2_hsotg *hsotg,
                                   struct dwc2_host_chan *chan)
{
        u32 max_hc_xfer_size = hsotg->params.max_transfer_size;
        u16 max_hc_pkt_count = hsotg->params.max_packet_count;
        u32 hcchar;
        u32 hctsiz = 0;
        u16 num_packets;
        u32 ec_mc;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        if (chan->do_ping) {
                if (!hsotg->params.host_dma) {
                        if (dbg_hc(chan))
                                dev_vdbg(hsotg->dev, "ping, no DMA\n");
                        dwc2_hc_do_ping(hsotg, chan);
                        chan->xfer_started = 1;
                        return;
                }

                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "ping, DMA\n");

                hctsiz |= TSIZ_DOPNG;
        }

        if (chan->do_split) {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "split\n");
                num_packets = 1;

                if (chan->complete_split && !chan->ep_is_in)
                        /*
                         * For CSPLIT OUT Transfer, set the size to 0 so the
                         * core doesn't expect any data written to the FIFO
                         */
                        chan->xfer_len = 0;
                else if (chan->ep_is_in || chan->xfer_len > chan->max_packet)
                        chan->xfer_len = chan->max_packet;
                else if (!chan->ep_is_in && chan->xfer_len > 188)
                        chan->xfer_len = 188;

                hctsiz |= chan->xfer_len << TSIZ_XFERSIZE_SHIFT &
                          TSIZ_XFERSIZE_MASK;

                /* For split set ec_mc for immediate retries */
                if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
                    chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                        ec_mc = 3;
                else
                        ec_mc = 1;
        } else {
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "no split\n");
                /*
                 * Ensure that the transfer length and packet count will fit
                 * in the widths allocated for them in the HCTSIZn register
                 */
                if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
                    chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
                        /*
                         * Make sure the transfer size is no larger than one
                         * (micro)frame's worth of data. (A check was done
                         * when the periodic transfer was accepted to ensure
                         * that a (micro)frame's worth of data can be
                         * programmed into a channel.)
                         */
                        u32 max_periodic_len =
                                chan->multi_count * chan->max_packet;

                        if (chan->xfer_len > max_periodic_len)
                                chan->xfer_len = max_periodic_len;
                } else if (chan->xfer_len > max_hc_xfer_size) {
                        /*
                         * Make sure that xfer_len is a multiple of max packet
                         * size
                         */
                        chan->xfer_len =
                                max_hc_xfer_size - chan->max_packet + 1;
                }

                if (chan->xfer_len > 0) {
                        num_packets = (chan->xfer_len + chan->max_packet - 1) /
                                        chan->max_packet;
                        if (num_packets > max_hc_pkt_count) {
                                num_packets = max_hc_pkt_count;
                                chan->xfer_len = num_packets * chan->max_packet;
                        }
                } else {
                        /* Need 1 packet for transfer length of 0 */
                        num_packets = 1;
                }

                if (chan->ep_is_in)
                        /*
                         * Always program an integral # of max packets for IN
                         * transfers
                         */
                        chan->xfer_len = num_packets * chan->max_packet;

                if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
                    chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                        /*
                         * Make sure that the multi_count field matches the
                         * actual transfer length
                         */
                        chan->multi_count = num_packets;

                if (chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                        dwc2_set_pid_isoc(chan);

                hctsiz |= chan->xfer_len << TSIZ_XFERSIZE_SHIFT &
                          TSIZ_XFERSIZE_MASK;

                /* The ec_mc gets the multi_count for non-split */
                ec_mc = chan->multi_count;
        }

        chan->start_pkt_count = num_packets;
        hctsiz |= num_packets << TSIZ_PKTCNT_SHIFT & TSIZ_PKTCNT_MASK;
        hctsiz |= chan->data_pid_start << TSIZ_SC_MC_PID_SHIFT &
                  TSIZ_SC_MC_PID_MASK;
        dwc2_writel(hsotg, hctsiz, HCTSIZ(chan->hc_num));
        if (dbg_hc(chan)) {
                dev_vdbg(hsotg->dev, "Wrote %08x to HCTSIZ(%d)\n",
                         hctsiz, chan->hc_num);

                dev_vdbg(hsotg->dev, "%s: Channel %d\n", __func__,
                         chan->hc_num);
                dev_vdbg(hsotg->dev, "   Xfer Size: %d\n",
                         (hctsiz & TSIZ_XFERSIZE_MASK) >>
                         TSIZ_XFERSIZE_SHIFT);
                dev_vdbg(hsotg->dev, "   Num Pkts: %d\n",
                         (hctsiz & TSIZ_PKTCNT_MASK) >>
                         TSIZ_PKTCNT_SHIFT);
                dev_vdbg(hsotg->dev, "   Start PID: %d\n",
                         (hctsiz & TSIZ_SC_MC_PID_MASK) >>
                         TSIZ_SC_MC_PID_SHIFT);
        }

        if (hsotg->params.host_dma) {
                dma_addr_t dma_addr;

                if (chan->align_buf) {
                        if (dbg_hc(chan))
                                dev_vdbg(hsotg->dev, "align_buf\n");
                        dma_addr = chan->align_buf;
                } else {
                        dma_addr = chan->xfer_dma;
                }
                dwc2_writel(hsotg, (u32)dma_addr, HCDMA(chan->hc_num));

                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "Wrote %08lx to HCDMA(%d)\n",
                                 (unsigned long)dma_addr, chan->hc_num);
        }

        /* Start the split */
        if (chan->do_split) {
                u32 hcsplt = dwc2_readl(hsotg, HCSPLT(chan->hc_num));

                hcsplt |= HCSPLT_SPLTENA;
                dwc2_writel(hsotg, hcsplt, HCSPLT(chan->hc_num));
        }

        hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));
        hcchar &= ~HCCHAR_MULTICNT_MASK;
        hcchar |= (ec_mc << HCCHAR_MULTICNT_SHIFT) & HCCHAR_MULTICNT_MASK;
        dwc2_hc_set_even_odd_frame(hsotg, chan, &hcchar);

        if (hcchar & HCCHAR_CHDIS)
                dev_warn(hsotg->dev,
                         "%s: chdis set, channel %d, hcchar 0x%08x\n",
                         __func__, chan->hc_num, hcchar);

        /* Set host channel enable after all other setup is complete */
        hcchar |= HCCHAR_CHENA;
        hcchar &= ~HCCHAR_CHDIS;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "   Multi Cnt: %d\n",
                         (hcchar & HCCHAR_MULTICNT_MASK) >>
                         HCCHAR_MULTICNT_SHIFT);

        dwc2_writel(hsotg, hcchar, HCCHAR(chan->hc_num));
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "Wrote %08x to HCCHAR(%d)\n", hcchar,
                         chan->hc_num);

        chan->xfer_started = 1;
        chan->requests++;

        if (!hsotg->params.host_dma &&
            !chan->ep_is_in && chan->xfer_len > 0)
                /* Load OUT packet into the appropriate Tx FIFO */
                dwc2_hc_write_packet(hsotg, chan);
}

/**
 * dwc2_hc_start_transfer_ddma() - Does the setup for a data transfer for a
 * host channel and starts the transfer in Descriptor DMA mode
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel
 *
 * Initializes HCTSIZ register. For a PING transfer the Do Ping bit is set.
 * Sets PID and NTD values. For periodic transfers initializes SCHED_INFO field
 * with micro-frame bitmap.
 *
 * Initializes HCDMA register with descriptor list address and CTD value then
 * starts the transfer via enabling the channel.
 */
void dwc2_hc_start_transfer_ddma(struct dwc2_hsotg *hsotg,
                                 struct dwc2_host_chan *chan)
{
        u32 hcchar;
        u32 hctsiz = 0;

        if (chan->do_ping)
                hctsiz |= TSIZ_DOPNG;

        if (chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                dwc2_set_pid_isoc(chan);

        /* Packet Count and Xfer Size are not used in Descriptor DMA mode */
        hctsiz |= chan->data_pid_start << TSIZ_SC_MC_PID_SHIFT &
                  TSIZ_SC_MC_PID_MASK;

        /* 0 - 1 descriptor, 1 - 2 descriptors, etc */
        hctsiz |= (chan->ntd - 1) << TSIZ_NTD_SHIFT & TSIZ_NTD_MASK;

        /* Non-zero only for high-speed interrupt endpoints */
        hctsiz |= chan->schinfo << TSIZ_SCHINFO_SHIFT & TSIZ_SCHINFO_MASK;

        if (dbg_hc(chan)) {
                dev_vdbg(hsotg->dev, "%s: Channel %d\n", __func__,
                         chan->hc_num);
                dev_vdbg(hsotg->dev, "   Start PID: %d\n",
                         chan->data_pid_start);
                dev_vdbg(hsotg->dev, "   NTD: %d\n", chan->ntd - 1);
        }

        dwc2_writel(hsotg, hctsiz, HCTSIZ(chan->hc_num));

        dma_sync_single_for_device(hsotg->dev, chan->desc_list_addr,
                                   chan->desc_list_sz, DMA_TO_DEVICE);

        dwc2_writel(hsotg, chan->desc_list_addr, HCDMA(chan->hc_num));

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "Wrote %pad to HCDMA(%d)\n",
                         &chan->desc_list_addr, chan->hc_num);

        hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));
        hcchar &= ~HCCHAR_MULTICNT_MASK;
        hcchar |= chan->multi_count << HCCHAR_MULTICNT_SHIFT &
                  HCCHAR_MULTICNT_MASK;

        if (hcchar & HCCHAR_CHDIS)
                dev_warn(hsotg->dev,
                         "%s: chdis set, channel %d, hcchar 0x%08x\n",
                         __func__, chan->hc_num, hcchar);

        /* Set host channel enable after all other setup is complete */
        hcchar |= HCCHAR_CHENA;
        hcchar &= ~HCCHAR_CHDIS;

        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "   Multi Cnt: %d\n",
                         (hcchar & HCCHAR_MULTICNT_MASK) >>
                         HCCHAR_MULTICNT_SHIFT);

        dwc2_writel(hsotg, hcchar, HCCHAR(chan->hc_num));
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "Wrote %08x to HCCHAR(%d)\n", hcchar,
                         chan->hc_num);

        chan->xfer_started = 1;
        chan->requests++;
}

/**
 * dwc2_hc_continue_transfer() - Continues a data transfer that was started by
 * a previous call to dwc2_hc_start_transfer()
 *
 * @hsotg: Programming view of DWC_otg controller
 * @chan:  Information needed to initialize the host channel
 *
 * The caller must ensure there is sufficient space in the request queue and Tx
 * Data FIFO. This function should only be called in Slave mode. In DMA mode,
 * the controller acts autonomously to complete transfers programmed to a host
 * channel.
 *
 * For an OUT transfer, a new data packet is loaded into the appropriate FIFO
 * if there is any data remaining to be queued. For an IN transfer, another
 * data packet is always requested. For the SETUP phase of a control transfer,
 * this function does nothing.
 *
 * Return: 1 if a new request is queued, 0 if no more requests are required
 * for this transfer
 */
static int dwc2_hc_continue_transfer(struct dwc2_hsotg *hsotg,
                                     struct dwc2_host_chan *chan)
{
        if (dbg_hc(chan))
                dev_vdbg(hsotg->dev, "%s: Channel %d\n", __func__,
                         chan->hc_num);

        if (chan->do_split)
                /* SPLITs always queue just once per channel */
                return 0;

        if (chan->data_pid_start == DWC2_HC_PID_SETUP)
                /* SETUPs are queued only once since they can't be NAK'd */
                return 0;

        if (chan->ep_is_in) {
                /*
                 * Always queue another request for other IN transfers. If
                 * back-to-back INs are issued and NAKs are received for both,
                 * the driver may still be processing the first NAK when the
                 * second NAK is received. When the interrupt handler clears
                 * the NAK interrupt for the first NAK, the second NAK will
                 * not be seen. So we can't depend on the NAK interrupt
                 * handler to requeue a NAK'd request. Instead, IN requests
                 * are issued each time this function is called. When the
                 * transfer completes, the extra requests for the channel will
                 * be flushed.
                 */
                u32 hcchar = dwc2_readl(hsotg, HCCHAR(chan->hc_num));

                dwc2_hc_set_even_odd_frame(hsotg, chan, &hcchar);
                hcchar |= HCCHAR_CHENA;
                hcchar &= ~HCCHAR_CHDIS;
                if (dbg_hc(chan))
                        dev_vdbg(hsotg->dev, "   IN xfer: hcchar = 0x%08x\n",
                                 hcchar);
                dwc2_writel(hsotg, hcchar, HCCHAR(chan->hc_num));
                chan->requests++;
                return 1;
        }

        /* OUT transfers */

        if (chan->xfer_count < chan->xfer_len) {
                if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
                    chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
                        u32 hcchar = dwc2_readl(hsotg,
                                                HCCHAR(chan->hc_num));

                        dwc2_hc_set_even_odd_frame(hsotg, chan,
                                                   &hcchar);
                }

                /* Load OUT packet into the appropriate Tx FIFO */
                dwc2_hc_write_packet(hsotg, chan);
                chan->requests++;
                return 1;
        }

        return 0;
}

/*
 * =========================================================================
 *  HCD
 * =========================================================================
 */

/*
 * Processes all the URBs in a single list of QHs. Completes them with
 * -ETIMEDOUT and frees the QTD.
 *
 * Must be called with interrupt disabled and spinlock held
 */
static void dwc2_kill_urbs_in_qh_list(struct dwc2_hsotg *hsotg,
                                      struct list_head *qh_list)
{
        struct dwc2_qh *qh, *qh_tmp;
        struct dwc2_qtd *qtd, *qtd_tmp;

        list_for_each_entry_safe(qh, qh_tmp, qh_list, qh_list_entry) {
                list_for_each_entry_safe(qtd, qtd_tmp, &qh->qtd_list,
                                         qtd_list_entry) {
                        dwc2_host_complete(hsotg, qtd, -ECONNRESET);
                        dwc2_hcd_qtd_unlink_and_free(hsotg, qtd, qh);
                }
        }
}

static void dwc2_qh_list_free(struct dwc2_hsotg *hsotg,
                              struct list_head *qh_list)
{
        struct dwc2_qtd *qtd, *qtd_tmp;
        struct dwc2_qh *qh, *qh_tmp;
        unsigned long flags;

        if (!qh_list->next)
                /* The list hasn't been initialized yet */
                return;

        spin_lock_irqsave(&hsotg->lock, flags);

        /* Ensure there are no QTDs or URBs left */
        dwc2_kill_urbs_in_qh_list(hsotg, qh_list);

        list_for_each_entry_safe(qh, qh_tmp, qh_list, qh_list_entry) {
                dwc2_hcd_qh_unlink(hsotg, qh);

                /* Free each QTD in the QH's QTD list */
                list_for_each_entry_safe(qtd, qtd_tmp, &qh->qtd_list,
                                         qtd_list_entry)
                        dwc2_hcd_qtd_unlink_and_free(hsotg, qtd, qh);

                if (qh->channel && qh->channel->qh == qh)
                        qh->channel->qh = NULL;

                spin_unlock_irqrestore(&hsotg->lock, flags);
                dwc2_hcd_qh_free(hsotg, qh);
                spin_lock_irqsave(&hsotg->lock, flags);
        }

        spin_unlock_irqrestore(&hsotg->lock, flags);
}

/*
 * Responds with an error status of -ETIMEDOUT to all URBs in the non-periodic
 * and periodic schedules. The QTD associated with each URB is removed from
 * the schedule and freed. This function may be called when a disconnect is
 * detected or when the HCD is being stopped.
 *
 * Must be called with interrupt disabled and spinlock held
 */
static void dwc2_kill_all_urbs(struct dwc2_hsotg *hsotg)
{
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->non_periodic_sched_inactive);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->non_periodic_sched_waiting);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->non_periodic_sched_active);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->periodic_sched_inactive);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->periodic_sched_ready);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->periodic_sched_assigned);
        dwc2_kill_urbs_in_qh_list(hsotg, &hsotg->periodic_sched_queued);
}

/**
 * dwc2_hcd_start() - Starts the HCD when switching to Host mode
 *
 * @hsotg: Pointer to struct dwc2_hsotg
 */
void dwc2_hcd_start(struct dwc2_hsotg *hsotg)
{
        u32 hprt0;

        if (hsotg->op_state == OTG_STATE_B_HOST) {
                /*
                 * Reset the port. During a HNP mode switch the reset
                 * needs to occur within 1ms and have a duration of at
                 * least 50ms.
                 */
                hprt0 = dwc2_read_hprt0(hsotg);
                hprt0 |= HPRT0_RST;
                dwc2_writel(hsotg, hprt0, HPRT0);
        }

        queue_delayed_work(hsotg->wq_otg, &hsotg->start_work,
                           msecs_to_jiffies(50));
}

/* Must be called with interrupt disabled and spinlock held */
static void dwc2_hcd_cleanup_channels(struct dwc2_hsotg *hsotg)
{
        int num_channels = hsotg->params.host_channels;
        struct dwc2_host_chan *channel;
        u32 hcchar;
        int i;

        if (!hsotg->params.host_dma) {
                /* Flush out any channel requests in slave mode */
                for (i = 0; i < num_channels; i++) {
                        channel = hsotg->hc_ptr_array[i];
                        if (!list_empty(&channel->hc_list_entry))
                                continue;
                        hcchar = dwc2_readl(hsotg, HCCHAR(i));
                        if (hcchar & HCCHAR_CHENA) {
                                hcchar &= ~(HCCHAR_CHENA | HCCHAR_EPDIR);
                                hcchar |= HCCHAR_CHDIS;
                                dwc2_writel(hsotg, hcchar, HCCHAR(i));
                        }
                }
        }

        for (i = 0; i < num_channels; i++) {
                channel = hsotg->hc_ptr_array[i];
                if (!list_empty(&channel->hc_list_entry))
                        continue;
                hcchar = dwc2_readl(hsotg, HCCHAR(i));
                if (hcchar & HCCHAR_CHENA) {
                        /* Halt the channel */
                        hcchar |= HCCHAR_CHDIS;
                        dwc2_writel(hsotg, hcchar, HCCHAR(i));
                }

                dwc2_hc_cleanup(hsotg, channel);
                list_add_tail(&channel->hc_list_entry, &hsotg->free_hc_list);
                /*
                 * Added for Descriptor DMA to prevent channel double cleanup in
                 * release_channel_ddma(), which is called from ep_disable when
                 * device disconnects
                 */
                channel->qh = NULL;
        }
        /* All channels have been freed, mark them available */
        if (hsotg->params.uframe_sched) {
                hsotg->available_host_channels =
                        hsotg->params.host_channels;
        } else {
                hsotg->non_periodic_channels = 0;
                hsotg->periodic_channels = 0;
        }
}

/**
 * dwc2_hcd_connect() - Handles connect of the HCD
 *
 * @hsotg: Pointer to struct dwc2_hsotg
 *
 * Must be called with interrupt disabled and spinlock held
 */
void dwc2_hcd_connect(struct dwc2_hsotg *hsotg)
{
        if (hsotg->lx_state != DWC2_L0)
                usb_hcd_resume_root_hub(hsotg->priv);

        hsotg->flags.b.port_connect_status_change = 1;
        hsotg->flags.b.port_connect_status = 1;
}

/**
 * dwc2_hcd_disconnect() - Handles disconnect of the HCD
 *
 * @hsotg: Pointer to struct dwc2_hsotg
 * @force: If true, we won't try to reconnect even if we see device connected.
 *
 * Must be called with interrupt disabled and spinlock held
 */
void dwc2_hcd_disconnect(struct dwc2_hsotg *hsotg, bool force)
{
        u32 intr;
        u32 hprt0;

        /* Set status flags for the hub driver */
        hsotg->flags.b.port_connect_status_change = 1;
        hsotg->flags.b.port_connect_status = 0;

        /*
         * Shutdown any transfers in process by clearing the Tx FIFO Empty
         * interrupt mask and status bits and disabling subsequent host
         * channel interrupts.
         */
        intr = dwc2_readl(hsotg, GINTMSK);
        intr &= ~(GINTSTS_NPTXFEMP | GINTSTS_PTXFEMP | GINTSTS_HCHINT);
        dwc2_writel(hsotg, intr, GINTMSK);
        intr = GINTSTS_NPTXFEMP | GINTSTS_PTXFEMP | GINTSTS_HCHINT;
        dwc2_writel(hsotg, intr, GINTSTS);

        /*
         * Turn off the vbus power only if the core has transitioned to device
         * mode. If still in host mode, need to keep power on to detect a
         * reconnection.
         */
        if (dwc2_is_device_mode(hsotg)) {
                if (hsotg->op_state != OTG_STATE_A_SUSPEND) {
                        dev_dbg(hsotg->dev, "Disconnect: PortPower off\n");
                        dwc2_writel(hsotg, 0, HPRT0);
                }

                dwc2_disable_host_interrupts(hsotg);
        }

        /* Respond with an error status to all URBs in the schedule */
        dwc2_kill_all_urbs(hsotg);

        if (dwc2_is_host_mode(hsotg))
                /* Clean up any host channels that were in use */
                dwc2_hcd_cleanup_channels(hsotg);

        dwc2_host_disconnect(hsotg);

        /*
         * Add an extra check here to see if we're actually connected but
         * we don't have a detection interrupt pending.  This can happen if:
         *   1. hardware sees connect
         *   2. hardware sees disconnect
         *   3. hardware sees connect
         *   4. dwc2_port_intr() - clears connect interrupt
         *   5. dwc2_handle_common_intr() - calls here
         *
         * Without the extra check here we will end calling disconnect
         * and won't get any future interrupts to handle the connect.
         */
        if (!force) {
                hprt0 = dwc2_readl(hsotg, HPRT0);
                if (!(hprt0 & HPRT0_CONNDET) && (hprt0 & HPRT0_CONNSTS))
                        dwc2_hcd_connect(hsotg);
        }
}

/**
 * dwc2_hcd_rem_wakeup() - Handles Remote Wakeup
 *
 * @hsotg: Pointer to struct dwc2_hsotg
 */
static void dwc2_hcd_rem_wakeup(struct dwc2_hsotg *hsotg)
{
        if (hsotg->bus_suspended) {
                hsotg->flags.b.port_suspend_change = 1;
                usb_hcd_resume_root_hub(hsotg->priv);
        }

        if (hsotg->lx_state == DWC2_L1)
                hsotg->flags.b.port_l1_change = 1;
}

/**
 * dwc2_hcd_stop() - Halts the DWC_otg host mode operations in a clean manner
 *
 * @hsotg: Pointer to struct dwc2_hsotg
 *
 * Must be called with interrupt disabled and spinlock held
 */
void dwc2_hcd_stop(struct dwc2_hsotg *hsotg)
{
        dev_dbg(hsotg->dev, "DWC OTG HCD STOP\n");

        /*
         * The root hub should be disconnected before this function is called.
         * The disconnect will clear the QTD lists (via ..._hcd_urb_dequeue)
         * and the QH lists (via ..._hcd_endpoint_disable).
         */

        /* Turn off all host-specific interrupts */
        dwc2_disable_host_interrupts(hsotg);

        /* Turn off the vbus power */
        dev_dbg(hsotg->dev, "PortPower off\n");
        dwc2_writel(hsotg, 0, HPRT0);
}

/* Caller must hold driver lock */
static int dwc2_hcd_urb_enqueue(struct dwc2_hsotg *hsotg,
                                struct dwc2_hcd_urb *urb, struct dwc2_qh *qh,
                                struct dwc2_qtd *qtd)
{
        u32 intr_mask;
        int retval;
        int dev_speed;

        if (!hsotg->flags.b.port_connect_status) {
                /* No longer connected */
                dev_err(hsotg->dev, "Not connected\n");
                return -ENODEV;
        }

        dev_speed = dwc2_host_get_speed(hsotg, urb->priv);

        /* Some configurations cannot support LS traffic on a FS root port */
        if ((dev_speed == USB_SPEED_LOW) &&
            (hsotg->hw_params.fs_phy_type == GHWCFG2_FS_PHY_TYPE_DEDICATED) &&
            (hsotg->hw_params.hs_phy_type == GHWCFG2_HS_PHY_TYPE_UTMI)) {
                u32 hprt0 = dwc2_readl(hsotg, HPRT0);
                u32 prtspd = (hprt0 & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;

                if (prtspd == HPRT0_SPD_FULL_SPEED)
                        return -ENODEV;
        }

        if (!qtd)
                return -EINVAL;

        dwc2_hcd_qtd_init(qtd, urb);
        retval = dwc2_hcd_qtd_add(hsotg, qtd, qh);
        if (retval) {
                dev_err(hsotg->dev,
                        "DWC OTG HCD URB Enqueue failed adding QTD. Error status %d\n",
                        retval);
                return retval;
        }

        intr_mask = dwc2_readl(hsotg, GINTMSK);
        if (!(intr_mask & GINTSTS_SOF)) {
                enum dwc2_transaction_type tr_type;

                if (qtd->qh->ep_type == USB_ENDPOINT_XFER_BULK &&
                    !(qtd->urb->flags & URB_GIVEBACK_ASAP))
                        /*
                         * Do not schedule SG transactions until qtd has
                         * URB_GIVEBACK_ASAP set
                         */
                        return 0;

                tr_type = dwc2_hcd_select_transactions(hsotg);
                if (tr_type != DWC2_TRANSACTION_NONE)
                        dwc2_hcd_queue_transactions(hsotg, tr_type);
        }

        return 0;
}

/* Must be called with interrupt disabled and spinlock held */
static int dwc2_hcd_urb_dequeue(struct dwc2_hsotg *hsotg,
                                struct dwc2_hcd_urb *urb)
{
        struct dwc2_qh *qh;
        struct dwc2_qtd *urb_qtd;

        urb_qtd = urb->qtd;
        if (!urb_qtd) {
                dev_dbg(hsotg->dev, "## Urb QTD is NULL ##\n");
                return -EINVAL;
        }

        qh = urb_qtd->qh;
        if (!qh) {
                dev_dbg(hsotg->dev, "## Urb QTD QH is NULL ##\n");
                return -EINVAL;
        }

        urb->priv = NULL;

        if (urb_qtd->in_process && qh->channel) {
                dwc2_dump_channel_info(hsotg, qh->channel);

                /* The QTD is in process (it has been assigned to a channel) */
                if (hsotg->flags.b.port_connect_status)
                        /*
                         * If still connected (i.e. in host mode), halt the
                         * channel so it can be used for other transfers. If
                         * no longer connected, the host registers can't be
                         * written to halt the channel since the core is in
                         * device mode.
                         */
                        dwc2_hc_halt(hsotg, qh->channel,
                                     DWC2_HC_XFER_URB_DEQUEUE);
        }

        /*
         * Free the QTD and clean up the associated QH. Leave the QH in the
         * schedule if it has any remaining QTDs.
         */
        if (!hsotg->params.dma_desc_enable) {
                u8 in_process = urb_qtd->in_process;

                dwc2_hcd_qtd_unlink_and_free(hsotg, urb_qtd, qh);
                if (in_process) {
                        dwc2_hcd_qh_deactivate(hsotg, qh, 0);
                        qh->channel = NULL;
                } else if (list_empty(&qh->qtd_list)) {
                        dwc2_hcd_qh_unlink(hsotg, qh);
                }
        } else {
                dwc2_hcd_qtd_unlink_and_free(hsotg, urb_qtd, qh);
        }

        return 0;
}

/* Must NOT be called with interrupt disabled or spinlock held */
static int dwc2_hcd_endpoint_disable(struct dwc2_hsotg *hsotg,
                                     struct usb_host_endpoint *ep, int retry)
{
        struct dwc2_qtd *qtd, *qtd_tmp;
        struct dwc2_qh *qh;

        unsigned long flags;
        int rc;

        spin_lock_irqsave(&hsotg->lock, flags);

        qh = ep->hcpriv;
        if (!qh) {
                rc = -EINVAL;
                goto err;
        }

        while (!list_empty(&qh->qtd_list) && retry--) {
                if (retry == 0) {
                        dev_err(hsotg->dev,
                                "## timeout in dwc2_hcd_endpoint_disable() ##\n");
                        rc = -EBUSY;
                        goto err;
                }

                spin_unlock_irqrestore(&hsotg->lock, flags);
                msleep(20);
                spin_lock_irqsave(&hsotg->lock, flags);
                qh = ep->hcpriv;
                if (!qh) {
                        rc = -EINVAL;
                        goto err;
                }
        }

        dwc2_hcd_qh_unlink(hsotg, qh);

        /* Free each QTD in the QH's QTD list */
        list_for_each_entry_safe(qtd, qtd_tmp, &qh->qtd_list, qtd_list_entry)
                dwc2_hcd_qtd_unlink_and_free(hsotg, qtd, qh);

        ep->hcpriv = NULL;

        if (qh->channel && qh->channel->qh == qh)
                qh->channel->qh = NULL;

        spin_unlock_irqrestore(&hsotg->lock, flags);

        dwc2_hcd_qh_free(hsotg, qh);

        return 0;

err:
        ep->hcpriv = NULL;
        spin_unlock_irqrestore(&hsotg->lock, flags);

        return rc;
}

/* Must be called with interrupt disabled and spinlock held */
static int dwc2_hcd_endpoint_reset(struct dwc2_hsotg *hsotg,
                                   struct usb_host_endpoint *ep)
{
        struct dwc2_qh *qh = ep->hcpriv;

        if (!qh)
                return -EINVAL;

        qh->data_toggle = DWC2_HC_PID_DATA0;

        return 0;
}

/**
 * dwc2_core_init() - Initializes the DWC_otg controller registers and
 * prepares the core for device mode or host mode operation
 *
 * @hsotg:         Programming view of the DWC_otg controller
 * @initial_setup: If true then this is the first init for this instance.
 */
int dwc2_core_init(struct dwc2_hsotg *hsotg, bool initial_setup)
{
        u32 usbcfg, otgctl;
        int retval;

        dev_dbg(hsotg->dev, "%s(%p)\n", __func__, hsotg);

        usbcfg = dwc2_readl(hsotg, GUSBCFG);

        /* Set ULPI External VBUS bit if needed */
        usbcfg &= ~GUSBCFG_ULPI_EXT_VBUS_DRV;
        if (hsotg->params.phy_ulpi_ext_vbus)
                usbcfg |= GUSBCFG_ULPI_EXT_VBUS_DRV;

        /* Set external TS Dline pulsing bit if needed */
        usbcfg &= ~GUSBCFG_TERMSELDLPULSE;
        if (hsotg->params.ts_dline)
                usbcfg |= GUSBCFG_TERMSELDLPULSE;

        dwc2_writel(hsotg, usbcfg, GUSBCFG);

        /*
         * Reset the Controller
         *
         * We only need to reset the controller if this is a re-init.
         * For the first init we know for sure that earlier code reset us (it
         * needed to in order to properly detect various parameters).
         */
        if (!initial_setup) {
                retval = dwc2_core_reset(hsotg, false);
                if (retval) {
                        dev_err(hsotg->dev, "%s(): Reset failed, aborting\n",
                                __func__);
                        return retval;
                }
        }

        /*
         * This needs to happen in FS mode before any other programming occurs
         */
        retval = dwc2_phy_init(hsotg, initial_setup);
        if (retval)
                return retval;

        /* Program the GAHBCFG Register */
        retval = dwc2_gahbcfg_init(hsotg);
        if (retval)
                return retval;

        /* Program the GUSBCFG register */
        dwc2_gusbcfg_init(hsotg);

        /* Program the GOTGCTL register */
        otgctl = dwc2_readl(hsotg, GOTGCTL);
        otgctl &= ~GOTGCTL_OTGVER;
        dwc2_writel(hsotg, otgctl, GOTGCTL);

        /* Clear the SRP success bit for FS-I2c */
        hsotg->srp_success = 0;

        /* Enable common interrupts */
        dwc2_enable_common_interrupts(hsotg);

        /*
         * Do device or host initialization based on mode during PCD and
         * HCD initialization
         */
        if (dwc2_is_host_mode(hsotg)) {
                dev_dbg(hsotg->dev, "Host Mode\n");
                hsotg->op_state = OTG_STATE_A_HOST;
        } else {
                dev_dbg(hsotg->dev, "Device Mode\n");
                hsotg->op_state = OTG_STATE_B_PERIPHERAL;
        }

        return 0;
}

/**
 * dwc2_core_host_init() - Initializes the DWC_otg controller registers for
 * Host mode
 *
 * @hsotg: Programming view of DWC_otg controller
 *
 * This function flushes the Tx and Rx FIFOs and flushes any entries in the
 * request queues. Host channels are reset to ensure that they are ready for
 * performing transfers.
 */
static void dwc2_core_host_init(struct dwc2_hsotg *hsotg)
{
        u32 hcfg, hfir, otgctl, usbcfg;

        dev_dbg(hsotg->dev, "%s(%p)\n", __func__, hsotg);

        /* Set HS/FS Timeout Calibration to 7 (max available value).
         * The number of PHY clocks that the application programs in
         * this field is added to the high/full speed interpacket timeout
         * duration in the core to account for any additional delays
         * introduced by the PHY. This can be required, because the delay
         * introduced by the PHY in generating the linestate condition
         * can vary from one PHY to another.
         */
        usbcfg = dwc2_readl(hsotg, GUSBCFG);
        usbcfg |= GUSBCFG_TOUTCAL(7);
        dwc2_writel(hsotg, usbcfg, GUSBCFG);

        /* Restart the Phy Clock */
        dwc2_writel(hsotg, 0, PCGCTL);

        /* Initialize Host Configuration Register */
        dwc2_init_fs_ls_pclk_sel(hsotg);
        if (hsotg->params.speed == DWC2_SPEED_PARAM_FULL ||
            hsotg->params.speed == DWC2_SPEED_PARAM_LOW) {
                hcfg = dwc2_readl(hsotg, HCFG);
                hcfg |= HCFG_FSLSSUPP;
                dwc2_writel(hsotg, hcfg, HCFG);
        }

        /*
         * This bit allows dynamic reloading of the HFIR register during
         * runtime. This bit needs to be programmed during initial configuration
         * and its value must not be changed during runtime.
         */
        if (hsotg->params.reload_ctl) {
                hfir = dwc2_readl(hsotg, HFIR);
                hfir |= HFIR_RLDCTRL;
                dwc2_writel(hsotg, hfir, HFIR);
        }

        if (hsotg->params.dma_desc_enable) {
                u32 op_mode = hsotg->hw_params.op_mode;

                if (hsotg->hw_params.snpsid < DWC2_CORE_REV_2_90a ||
                    !hsotg->hw_params.dma_desc_enable ||
                    op_mode == GHWCFG2_OP_MODE_SRP_CAPABLE_DEVICE ||
                    op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_DEVICE ||
                    op_mode == GHWCFG2_OP_MODE_UNDEFINED) {
                        dev_err(hsotg->dev,
                                "Hardware does not support descriptor DMA mode -\n");
                        dev_err(hsotg->dev,
                                "falling back to buffer DMA mode.\n");
                        hsotg->params.dma_desc_enable = false;
                } else {
                        hcfg = dwc2_readl(hsotg, HCFG);
                        hcfg |= HCFG_DESCDMA;
                        dwc2_writel(hsotg, hcfg, HCFG);
                }
        }

        /* Configure data FIFO sizes */
        dwc2_config_fifos(hsotg);

        /* TODO - check this */
        /* Clear Host Set HNP Enable in the OTG Control Register */
        otgctl = dwc2_readl(hsotg, GOTGCTL);
        otgctl &= ~GOTGCTL_HSTSETHNPEN;
        dwc2_writel(hsotg, otgctl, GOTGCTL);

        /* Make sure the FIFOs are flushed */
        dwc2_flush_tx_fifo(hsotg, 0x10 /* all TX FIFOs */);
        dwc2_flush_rx_fifo(hsotg);

        /* Clear Host Set HNP Enable in the OTG Control Register */
        otgctl = dwc2_readl(hsotg, GOTGCTL);
        otgctl &= ~GOTGCTL_HSTSETHNPEN;
        dwc2_writel(hsotg, otgctl, GOTGCTL);

        if (!hsotg->params.dma_desc_enable) {
                int num_channels, i;
                u32 hcchar;

                /* Flush out any leftover queued requests */
                num_channels = hsotg->params.host_channels;
                for (i = 0; i < num_channels; i++) {
                        hcchar = dwc2_readl(hsotg, HCCHAR(i));
                        if (hcchar & HCCHAR_CHENA) {
                                hcchar &= ~HCCHAR_CHENA;
                                hcchar |= HCCHAR_CHDIS;
                                hcchar &= ~HCCHAR_EPDIR;
                                dwc2_writel(hsotg, hcchar, HCCHAR(i));
                        }
                }

                /* Halt all channels to put them into a known state */
                for (i = 0; i < num_channels; i++) {
                        hcchar = dwc2_readl(hsotg, HCCHAR(i));
                        if (hcchar & HCCHAR_CHENA) {
                                hcchar |= HCCHAR_CHENA | HCCHAR_CHDIS;
                                hcchar &= ~HCCHAR_EPDIR;
                                dwc2_writel(hsotg, hcchar, HCCHAR(i));
                                dev_dbg(hsotg->dev, "%s: Halt channel %d\n",
                                        __func__, i);

                                if (dwc2_hsotg_wait_bit_clear(hsotg, HCCHAR(i),
                                                              HCCHAR_CHENA,
                                                              1000)) {
                                        dev_warn(hsotg->dev,
                                                 "Unable to clear enable on channel %d\n",
                                                 i);
                                }
                        }
                }
        }

        /* Enable ACG feature in host mode, if supported */
        dwc2_enable_acg(hsotg);

        /* Turn on the vbus power */
        dev_dbg(hsotg->dev, "Init: Port Power? op_state=%d\n", hsotg->op_state);
        if (hsotg->op_state == OTG_STATE_A_HOST) {
                u32 hprt0 = dwc2_read_hprt0(hsotg);

                dev_dbg(hsotg->dev, "Init: Power Port (%d)\n",
                        !!(hprt0 & HPRT0_PWR));
                if (!(hprt0 & HPRT0_PWR)) {
                        hprt0 |= HPRT0_PWR;
                        dwc2_writel(hsotg, hprt0, HPRT0);
                }
        }

        dwc2_enable_host_interrupts(hsotg);
}

/*
 * Initializes dynamic portions of the DWC_otg HCD state
 *
 * Must be called with interrupt disabled and spinlock held
 */
static void dwc2_hcd_reinit(struct dwc2_hsotg *hsotg)
{
        struct dwc2_host_chan *chan, *chan_tmp;
        int num_channels;
        int i;

        hsotg->flags.d32 = 0;
        hsotg->non_periodic_qh_ptr = &hsotg->non_periodic_sched_active;

        if (hsotg->params.uframe_sched) {
                hsotg->available_host_channels =
                        hsotg->params.host_channels;
        } else {
                hsotg->non_periodic_channels = 0;
                hsotg->periodic_channels = 0;
        }

        /*
         * Put all channels in the free channel list and clean up channel
         * states
         */
        list_for_each_entry_safe(chan, chan_tmp, &hsotg->free_hc_list,
                                 hc_list_entry)
                list_del_init(&chan->hc_list_entry);

        num_channels = hsotg->params.host_channels;
        for (i = 0; i < num_channels; i++) {
                chan = hsotg->hc_ptr_array[i];
                list_add_tail(&chan->hc_list_entry, &hsotg->free_hc_list);
                dwc2_hc_cleanup(hsotg, chan);
        }

        /* Initialize the DWC core for host mode operation */
        dwc2_core_host_init(hsotg);
}

static void dwc2_hc_init_split(struct dwc2_hsotg *hsotg,
                               struct dwc2_host_chan *chan,
                               struct dwc2_qtd *qtd, struct dwc2_hcd_urb *urb)
{
        int hub_addr, hub_port;

        chan->do_split = 1;
        chan->xact_pos = qtd->isoc_split_pos;
        chan->complete_split = qtd->complete_split;
        dwc2_host_hub_info(hsotg, urb->priv, &hub_addr, &hub_port);
        chan->hub_addr = (u8)hub_addr;
        chan->hub_port = (u8)hub_port;
}

static void dwc2_hc_init_xfer(struct dwc2_hsotg *hsotg,
                              struct dwc2_host_chan *chan,
                              struct dwc2_qtd *qtd)
{
        struct dwc2_hcd_urb *urb = qtd->urb;
        struct dwc2_hcd_iso_packet_desc *frame_desc;

        switch (dwc2_hcd_get_pipe_type(&urb->pipe_info)) {
        case USB_ENDPOINT_XFER_CONTROL:
                chan->ep_type = USB_ENDPOINT_XFER_CONTROL;

                switch (qtd->control_phase) {
                case DWC2_CONTROL_SETUP:
                        dev_vdbg(hsotg->dev, "  Control setup transaction\n");
                        chan->do_ping = 0;
                        chan->ep_is_in = 0;
                        chan->data_pid_start = DWC2_HC_PID_SETUP;
                        if (hsotg->params.host_dma)
                                chan->xfer_dma = urb->setup_dma;
                        else
                                chan->xfer_buf = urb->setup_packet;
                        chan->xfer_len = 8;
                        break;

                case DWC2_CONTROL_DATA:
                        dev_vdbg(hsotg->dev, "  Control data transaction\n");
                        chan->data_pid_start = qtd->data_toggle;
                        break;

                case DWC2_CONTROL_STATUS:
                        /*
                         * Direction is opposite of data direction or IN if no
                         * data
                         */
                        dev_vdbg(hsotg->dev, "  Control status transaction\n");
                        if (urb->length == 0)
                                chan->ep_is_in = 1;
                        else
                                chan->ep_is_in =
                                        dwc2_hcd_is_pipe_out(&urb->pipe_info);
                        if (chan->ep_is_in)
                                chan->do_ping = 0;
                        chan->data_pid_start = DWC2_HC_PID_DATA1;
                        chan->xfer_len = 0;
                        if (hsotg->params.host_dma)
                                chan->xfer_dma = hsotg->status_buf_dma;
                        else
                                chan->xfer_buf = hsotg->status_buf;
                        break;
                }
                break;

        case USB_ENDPOINT_XFER_BULK:
                chan->ep_type = USB_ENDPOINT_XFER_BULK;
                break;

        case USB_ENDPOINT_XFER_INT:
                chan->ep_type = USB_ENDPOINT_XFER_INT;
                break;

        case USB_ENDPOINT_XFER_ISOC:
                chan->ep_type = USB_ENDPOINT_XFER_ISOC;
                if (hsotg->params.dma_desc_enable)
                        break;

                frame_desc = &urb->iso_descs[qtd->isoc_frame_index];
                frame_desc->status = 0;

                if (hsotg->params.host_dma) {
                        chan->xfer_dma = urb->dma;
                        chan->xfer_dma += frame_desc->offset +
                                        qtd->isoc_split_offset;
                } else {
                        chan->xfer_buf = urb->buf;
                        chan->xfer_buf += frame_desc->offset +
                                        qtd->isoc_split_offset;
                }

                chan->xfer_len = frame_desc->length - qtd->isoc_split_offset;

                if (chan->xact_pos == DWC2_HCSPLT_XACTPOS_ALL) {
                        if (chan->xfer_len <= 188)
                                chan->xact_pos = DWC2_HCSPLT_XACTPOS_ALL;
                        else
                                chan->xact_pos = DWC2_HCSPLT_XACTPOS_BEGIN;
                }
                break;
        }
}

static int dwc2_alloc_split_dma_aligned_buf(struct dwc2_hsotg *hsotg,
                                            struct dwc2_qh *qh,
                                            struct dwc2_host_chan *chan)
{
        if (!hsotg->unaligned_cache ||
            chan->max_packet > DWC2_KMEM_UNALIGNED_BUF_SIZE)
                return -ENOMEM;

        if (!qh->dw_align_buf) {
                qh->dw_align_buf = kmem_cache_alloc(hsotg->unaligned_cache,
                                                    GFP_ATOMIC | GFP_DMA);
                if (!qh->dw_align_buf)
                        return -ENOMEM;
        }

        qh->dw_align_buf_dma = dma_map_single(hsotg->dev, qh->dw_align_buf,
                                              DWC2_KMEM_UNALIGNED_BUF_SIZE,
                                              DMA_FROM_DEVICE);

        if (dma_mapping_error(hsotg->dev, qh->dw_align_buf_dma)) {
                dev_err(hsotg->dev, "can't map align_buf\n");
                chan->align_buf = 0;
                return -EINVAL;
        }

        chan->align_buf = qh->dw_align_buf_dma;
        return 0;
}

#define DWC2_USB_DMA_ALIGN 4

static void dwc2_free_dma_aligned_buffer(struct urb *urb)
{
        void *stored_xfer_buffer;
        size_t length;

        if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
                return;

        /* Restore urb->transfer_buffer from the end of the allocated area */
        memcpy(&stored_xfer_buffer,
               PTR_ALIGN(urb->transfer_buffer + urb->transfer_buffer_length,
                         dma_get_cache_alignment()),
               sizeof(urb->transfer_buffer));

        if (usb_urb_dir_in(urb)) {
                if (usb_pipeisoc(urb->pipe))
                        length = urb->transfer_buffer_length;
                else
                        length = urb->actual_length;

                memcpy(stored_xfer_buffer, urb->transfer_buffer, length);
        }
        kfree(urb->transfer_buffer);
        urb->transfer_buffer = stored_xfer_buffer;

        urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
}

static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
{
        void *kmalloc_ptr;
        size_t kmalloc_size;

        if (urb->num_sgs || urb->sg ||
            urb->transfer_buffer_length == 0 ||
            !((uintptr_t)urb->transfer_buffer & (DWC2_USB_DMA_ALIGN - 1)))
                return 0;

        /*
         * Allocate a buffer with enough padding for original transfer_buffer
         * pointer. This allocation is guaranteed to be aligned properly for
         * DMA
         */
        kmalloc_size = urb->transfer_buffer_length +
                (dma_get_cache_alignment() - 1) +
                sizeof(urb->transfer_buffer);

        kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
        if (!kmalloc_ptr)
                return -ENOMEM;

        /*
         * Position value of original urb->transfer_buffer pointer to the end
         * of allocation for later referencing
         */
        memcpy(PTR_ALIGN(kmalloc_ptr + urb->transfer_buffer_length,
                         dma_get_cache_alignment()),
               &urb->transfer_buffer, sizeof(urb->transfer_buffer));

        if (usb_urb_dir_out(urb))
                memcpy(kmalloc_ptr, urb->transfer_buffer,
                       urb->transfer_buffer_length);
        urb->transfer_buffer = kmalloc_ptr;

        urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;

        return 0;
}

static int dwc2_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
                                gfp_t mem_flags)
{
        int ret;

        /* We assume setup_dma is always aligned; warn if not */
        WARN_ON_ONCE(urb->setup_dma &&
                     (urb->setup_dma & (DWC2_USB_DMA_ALIGN - 1)));

        ret = dwc2_alloc_dma_aligned_buffer(urb, mem_flags);
        if (ret)
                return ret;

        ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
        if (ret)
                dwc2_free_dma_aligned_buffer(urb);

        return ret;
}

static void dwc2_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
{
        usb_hcd_unmap_urb_for_dma(hcd, urb);
        dwc2_free_dma_aligned_buffer(urb);
}

/**
 * dwc2_assign_and_init_hc() - Assigns transactions from a QTD to a free host
 * channel and initializes the host channel to perform the transactions. The
 * host channel is removed from the free list.
 *
 * @hsotg: The HCD state structure
 * @qh:    Transactions from the first QTD for this QH are selected and assigned
 *         to a free host channel
 */
static int dwc2_assign_and_init_hc(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        struct dwc2_host_chan *chan;
        struct dwc2_hcd_urb *urb;
        struct dwc2_qtd *qtd;

        if (dbg_qh(qh))
                dev_vdbg(hsotg->dev, "%s(%p,%p)\n", __func__, hsotg, qh);

        if (list_empty(&qh->qtd_list)) {
                dev_dbg(hsotg->dev, "No QTDs in QH list\n");
                return -ENOMEM;
        }

        if (list_empty(&hsotg->free_hc_list)) {
                dev_dbg(hsotg->dev, "No free channel to assign\n");
                return -ENOMEM;
        }

        chan = list_first_entry(&hsotg->free_hc_list, struct dwc2_host_chan,
                                hc_list_entry);

        /* Remove host channel from free list */
        list_del_init(&chan->hc_list_entry);

        qtd = list_first_entry(&qh->qtd_list, struct dwc2_qtd, qtd_list_entry);
        urb = qtd->urb;
        qh->channel = chan;
        qtd->in_process = 1;

        /*
         * Use usb_pipedevice to determine device address. This address is
         * 0 before the SET_ADDRESS command and the correct address afterward.
         */
        chan->dev_addr = dwc2_hcd_get_dev_addr(&urb->pipe_info);
        chan->ep_num = dwc2_hcd_get_ep_num(&urb->pipe_info);
        chan->speed = qh->dev_speed;
        chan->max_packet = qh->maxp;

        chan->xfer_started = 0;
        chan->halt_status = DWC2_HC_XFER_NO_HALT_STATUS;
        chan->error_state = (qtd->error_count > 0);
        chan->halt_on_queue = 0;
        chan->halt_pending = 0;
        chan->requests = 0;

        /*
         * The following values may be modified in the transfer type section
         * below. The xfer_len value may be reduced when the transfer is
         * started to accommodate the max widths of the XferSize and PktCnt
         * fields in the HCTSIZn register.
         */

        chan->ep_is_in = (dwc2_hcd_is_pipe_in(&urb->pipe_info) != 0);
        if (chan->ep_is_in)
                chan->do_ping = 0;
        else
                chan->do_ping = qh->ping_state;

        chan->data_pid_start = qh->data_toggle;
        chan->multi_count = 1;

        if (urb->actual_length > urb->length &&
            !dwc2_hcd_is_pipe_in(&urb->pipe_info))
                urb->actual_length = urb->length;

        if (hsotg->params.host_dma)
                chan->xfer_dma = urb->dma + urb->actual_length;
        else
                chan->xfer_buf = (u8 *)urb->buf + urb->actual_length;

        chan->xfer_len = urb->length - urb->actual_length;
        chan->xfer_count = 0;

        /* Set the split attributes if required */
        if (qh->do_split)
                dwc2_hc_init_split(hsotg, chan, qtd, urb);
        else
                chan->do_split = 0;

        /* Set the transfer attributes */
        dwc2_hc_init_xfer(hsotg, chan, qtd);

        /* For non-dword aligned buffers */
        if (hsotg->params.host_dma && qh->do_split &&
            chan->ep_is_in && (chan->xfer_dma & 0x3)) {
                dev_vdbg(hsotg->dev, "Non-aligned buffer\n");
                if (dwc2_alloc_split_dma_aligned_buf(hsotg, qh, chan)) {
                        dev_err(hsotg->dev,
                                "Failed to allocate memory to handle non-aligned buffer\n");
                        /* Add channel back to free list */
                        chan->align_buf = 0;
                        chan->multi_count = 0;
                        list_add_tail(&chan->hc_list_entry,
                                      &hsotg->free_hc_list);
                        qtd->in_process = 0;
                        qh->channel = NULL;
                        return -ENOMEM;
                }
        } else {
                /*
                 * We assume that DMA is always aligned in non-split
                 * case or split out case. Warn if not.
                 */
                WARN_ON_ONCE(hsotg->params.host_dma &&
                             (chan->xfer_dma & 0x3));
                chan->align_buf = 0;
        }

        if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
            chan->ep_type == USB_ENDPOINT_XFER_ISOC)
                /*
                 * This value may be modified when the transfer is started
                 * to reflect the actual transfer length
                 */
                chan->multi_count = qh->maxp_mult;

        if (hsotg->params.dma_desc_enable) {
                chan->desc_list_addr = qh->desc_list_dma;
                chan->desc_list_sz = qh->desc_list_sz;
        }

        dwc2_hc_init(hsotg, chan);
        chan->qh = qh;

        return 0;
}

/**
 * dwc2_hcd_select_transactions() - Selects transactions from the HCD transfer
 * schedule and assigns them to available host channels. Called from the HCD
 * interrupt handler functions.
 *
 * @hsotg: The HCD state structure
 *
 * Return: The types of new transactions that were assigned to host channels
 */
enum dwc2_transaction_type dwc2_hcd_select_transactions(
                struct dwc2_hsotg *hsotg)
{
        enum dwc2_transaction_type ret_val = DWC2_TRANSACTION_NONE;
        struct list_head *qh_ptr;
        struct dwc2_qh *qh;
        int num_channels;

#ifdef DWC2_DEBUG_SOF
        dev_vdbg(hsotg->dev, "  Select Transactions\n");
#endif

        /* Process entries in the periodic ready list */
        qh_ptr = hsotg->periodic_sched_ready.next;
        while (qh_ptr != &hsotg->periodic_sched_ready) {
                if (list_empty(&hsotg->free_hc_list))
                        break;
                if (hsotg->params.uframe_sched) {
                        if (hsotg->available_host_channels <= 1)
                                break;
                        hsotg->available_host_channels--;
                }
                qh = list_entry(qh_ptr, struct dwc2_qh, qh_list_entry);
                if (dwc2_assign_and_init_hc(hsotg, qh))
                        break;

                /*
                 * Move the QH from the periodic ready schedule to the
                 * periodic assigned schedule
                 */
                qh_ptr = qh_ptr->next;
                list_move_tail(&qh->qh_list_entry,
                               &hsotg->periodic_sched_assigned);
                ret_val = DWC2_TRANSACTION_PERIODIC;
        }

        /*
         * Process entries in the inactive portion of the non-periodic
         * schedule. Some free host channels may not be used if they are
         * reserved for periodic transfers.
         */
        num_channels = hsotg->params.host_channels;
        qh_ptr = hsotg->non_periodic_sched_inactive.next;
        while (qh_ptr != &hsotg->non_periodic_sched_inactive) {
                if (!hsotg->params.uframe_sched &&
                    hsotg->non_periodic_channels >= num_channels -
                                                hsotg->periodic_channels)
                        break;
                if (list_empty(&hsotg->free_hc_list))
                        break;
                qh = list_entry(qh_ptr, struct dwc2_qh, qh_list_entry);
                if (hsotg->params.uframe_sched) {
                        if (hsotg->available_host_channels < 1)
                                break;
                        hsotg->available_host_channels--;
                }

                if (dwc2_assign_and_init_hc(hsotg, qh))
                        break;

                /*
                 * Move the QH from the non-periodic inactive schedule to the
                 * non-periodic active schedule
                 */
                qh_ptr = qh_ptr->next;
                list_move_tail(&qh->qh_list_entry,
                               &hsotg->non_periodic_sched_active);

                if (ret_val == DWC2_TRANSACTION_NONE)
                        ret_val = DWC2_TRANSACTION_NON_PERIODIC;
                else
                        ret_val = DWC2_TRANSACTION_ALL;

                if (!hsotg->params.uframe_sched)
                        hsotg->non_periodic_channels++;
        }

        return ret_val;
}

/**
 * dwc2_queue_transaction() - Attempts to queue a single transaction request for
 * a host channel associated with either a periodic or non-periodic transfer
 *
 * @hsotg: The HCD state structure
 * @chan:  Host channel descriptor associated with either a periodic or
 *         non-periodic transfer
 * @fifo_dwords_avail: Number of DWORDs available in the periodic Tx FIFO
 *                     for periodic transfers or the non-periodic Tx FIFO
 *                     for non-periodic transfers
 *
 * Return: 1 if a request is queued and more requests may be needed to
 * complete the transfer, 0 if no more requests are required for this
 * transfer, -1 if there is insufficient space in the Tx FIFO
 *
 * This function assumes that there is space available in the appropriate
 * request queue. For an OUT transfer or SETUP transaction in Slave mode,
 * it checks whether space is available in the appropriate Tx FIFO.
 *
 * Must be called with interrupt disabled and spinlock held
 */
static int dwc2_queue_transaction(struct dwc2_hsotg *hsotg,
                                  struct dwc2_host_chan *chan,
                                  u16 fifo_dwords_avail)
{
        int retval = 0;

        if (chan->do_split)
                /* Put ourselves on the list to keep order straight */
                list_move_tail(&chan->split_order_list_entry,
                               &hsotg->split_order);

        if (hsotg->params.host_dma) {
                if (hsotg->params.dma_desc_enable) {
                        if (!chan->xfer_started ||
                            chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
                                dwc2_hcd_start_xfer_ddma(hsotg, chan->qh);
                                chan->qh->ping_state = 0;
                        }
                } else if (!chan->xfer_started) {
                        dwc2_hc_start_transfer(hsotg, chan);
                        chan->qh->ping_state = 0;
                }
        } else if (chan->halt_pending) {
                /* Don't queue a request if the channel has been halted */
        } else if (chan->halt_on_queue) {
                dwc2_hc_halt(hsotg, chan, chan->halt_status);
        } else if (chan->do_ping) {
                if (!chan->xfer_started)
                        dwc2_hc_start_transfer(hsotg, chan);
        } else if (!chan->ep_is_in ||
                   chan->data_pid_start == DWC2_HC_PID_SETUP) {
                if ((fifo_dwords_avail * 4) >= chan->max_packet) {
                        if (!chan->xfer_started) {
                                dwc2_hc_start_transfer(hsotg, chan);
                                retval = 1;
                        } else {
                                retval = dwc2_hc_continue_transfer(hsotg, chan);
                        }
                } else {
                        retval = -1;
                }
        } else {
                if (!chan->xfer_started) {
                        dwc2_hc_start_transfer(hsotg, chan);
                        retval = 1;
                } else {
                        retval = dwc2_hc_continue_transfer(hsotg, chan);
                }
        }

        return retval;
}

/*
 * Processes periodic channels for the next frame and queues transactions for
 * these channels to the DWC_otg controller. After queueing transactions, the
 * Periodic Tx FIFO Empty interrupt is enabled if there are more transactions
 * to queue as Periodic Tx FIFO or request queue space becomes available.
 * Otherwise, the Periodic Tx FIFO Empty interrupt is disabled.
 *
 * Must be called with interrupt disabled and spinlock held
 */
static void dwc2_process_periodic_channels(struct dwc2_hsotg *hsotg)
{
        struct list_head *qh_ptr;
        struct dwc2_qh *qh;
        u32 tx_status;
        u32 fspcavail;
        u32 gintmsk;
        int status;
        bool no_queue_space = false;
        bool no_fifo_space = false;
        u32 qspcavail;

        /* If empty list then just adjust interrupt enables */
        if (list_empty(&hsotg->periodic_sched_assigned))
                goto exit;

        if (dbg_perio())
                dev_vdbg(hsotg->dev, "Queue periodic transactions\n");

        tx_status = dwc2_readl(hsotg, HPTXSTS);
        qspcavail = (tx_status & TXSTS_QSPCAVAIL_MASK) >>
                    TXSTS_QSPCAVAIL_SHIFT;
        fspcavail = (tx_status & TXSTS_FSPCAVAIL_MASK) >>
                    TXSTS_FSPCAVAIL_SHIFT;

        if (dbg_perio()) {
                dev_vdbg(hsotg->dev, "  P Tx Req Queue Space Avail (before queue): %d\n",
                         qspcavail);
                dev_vdbg(hsotg->dev, "  P Tx FIFO Space Avail (before queue): %d\n",
                         fspcavail);
        }

        qh_ptr = hsotg->periodic_sched_assigned.next;
        while (qh_ptr != &hsotg->periodic_sched_assigned) {
                tx_status = dwc2_readl(hsotg, HPTXSTS);
                qspcavail = (tx_status & TXSTS_QSPCAVAIL_MASK) >>
                            TXSTS_QSPCAVAIL_SHIFT;
                if (qspcavail == 0) {
                        no_queue_space = true;
                        break;
                }

                qh = list_entry(qh_ptr, struct dwc2_qh, qh_list_entry);
                if (!qh->channel) {
                        qh_ptr = qh_ptr->next;
                        continue;
                }

                /* Make sure EP's TT buffer is clean before queueing qtds */
                if (qh->tt_buffer_dirty) {
                        qh_ptr = qh_ptr->next;
                        continue;
                }

                /*
                 * Set a flag if we're queuing high-bandwidth in slave mode.
                 * The flag prevents any halts to get into the request queue in
                 * the middle of multiple high-bandwidth packets getting queued.
                 */
                if (!hsotg->params.host_dma &&
                    qh->channel->multi_count > 1)
                        hsotg->queuing_high_bandwidth = 1;

                fspcavail = (tx_status & TXSTS_FSPCAVAIL_MASK) >>
                            TXSTS_FSPCAVAIL_SHIFT;
                status = dwc2_queue_transaction(hsotg, qh->channel, fspcavail);
                if (status < 0) {
                        no_fifo_space = true;
                        break;
                }

                /*
                 * In Slave mode, stay on the current transfer until there is
                 * nothing more to do or the high-bandwidth request count is
                 * reached. In DMA mode, only need to queue one request. The
                 * controller automatically handles multiple packets for
                 * high-bandwidth transfers.
                 */
                if (hsotg->params.host_dma || status == 0 ||
                    qh->channel->requests == qh->channel->multi_count) {
                        qh_ptr = qh_ptr->next;
                        /*
                         * Move the QH from the periodic assigned schedule to
                         * the periodic queued schedule
                         */
                        list_move_tail(&qh->qh_list_entry,
                                       &hsotg->periodic_sched_queued);

                        /* done queuing high bandwidth */
                        hsotg->queuing_high_bandwidth = 0;
                }
        }

exit:
        if (no_queue_space || no_fifo_space ||
            (!hsotg->params.host_dma &&
             !list_empty(&hsotg->periodic_sched_assigned))) {
                /*
                 * May need to queue more transactions as the request
                 * queue or Tx FIFO empties. Enable the periodic Tx
                 * FIFO empty interrupt. (Always use the half-empty
                 * level to ensure that new requests are loaded as
                 * soon as possible.)
                 */
                gintmsk = dwc2_readl(hsotg, GINTMSK);
                if (!(gintmsk & GINTSTS_PTXFEMP)) {
                        gintmsk |= GINTSTS_PTXFEMP;
                        dwc2_writel(hsotg, gintmsk, GINTMSK);
                }
        } else {
                /*
                 * Disable the Tx FIFO empty interrupt since there are
                 * no more transactions that need to be queued right
                 * now. This function is called from interrupt
                 * handlers to queue more transactions as transfer
                 * states change.
                 */
                gintmsk = dwc2_readl(hsotg, GINTMSK);
                if (gintmsk & GINTSTS_PTXFEMP) {
                        gintmsk &= ~GINTSTS_PTXFEMP;
                        dwc2_writel(hsotg, gintmsk, GINTMSK);
                }
        }