root/drivers/usb/host/ehci-fsl.c
// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright 2005-2009 MontaVista Software, Inc.
 * Copyright 2008,2012,2015      Freescale Semiconductor, Inc.
 *
 * Ported to 834x by Randy Vinson <rvinson@mvista.com> using code provided
 * by Hunter Wu.
 * Power Management support by Dave Liu <daveliu@freescale.com>,
 * Jerry Huang <Chang-Ming.Huang@freescale.com> and
 * Anton Vorontsov <avorontsov@ru.mvista.com>.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/err.h>
#include <linux/usb.h>
#include <linux/usb/ehci_def.h>
#include <linux/usb/hcd.h>
#include <linux/usb/otg.h>
#include <linux/platform_device.h>
#include <linux/fsl_devices.h>
#include <linux/of.h>
#include <linux/io.h>

#include "ehci.h"
#include "ehci-fsl.h"

#define DRIVER_DESC "Freescale EHCI Host controller driver"
#define DRV_NAME "fsl-ehci"

static struct hc_driver __read_mostly fsl_ehci_hc_driver;

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */

/*
 * fsl_ehci_drv_probe - initialize FSL-based HCDs
 * @pdev: USB Host Controller being probed
 *
 * Context: task context, might sleep
 *
 * Allocates basic resources for this USB host controller.
 */
static int fsl_ehci_drv_probe(struct platform_device *pdev)
{
        struct fsl_usb2_platform_data *pdata;
        struct usb_hcd *hcd;
        struct resource *res;
        int irq;
        int retval;
        u32 tmp;

        pr_debug("initializing FSL-SOC USB Controller\n");

        /* Need platform data for setup */
        pdata = dev_get_platdata(&pdev->dev);
        if (!pdata) {
                dev_err(&pdev->dev,
                        "No platform data for %s.\n", dev_name(&pdev->dev));
                return -ENODEV;
        }

        /*
         * This is a host mode driver, verify that we're supposed to be
         * in host mode.
         */
        if (!((pdata->operating_mode == FSL_USB2_DR_HOST) ||
              (pdata->operating_mode == FSL_USB2_MPH_HOST) ||
              (pdata->operating_mode == FSL_USB2_DR_OTG))) {
                dev_err(&pdev->dev,
                        "Non Host Mode configured for %s. Wrong driver linked.\n",
                        dev_name(&pdev->dev));
                return -ENODEV;
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        hcd = __usb_create_hcd(&fsl_ehci_hc_driver, pdev->dev.parent,
                               &pdev->dev, dev_name(&pdev->dev), NULL);
        if (!hcd) {
                retval = -ENOMEM;
                goto err1;
        }

        hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(hcd->regs)) {
                retval = PTR_ERR(hcd->regs);
                goto err2;
        }

        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);

        pdata->regs = hcd->regs;

        if (pdata->power_budget)
                hcd->power_budget = pdata->power_budget;

        /*
         * do platform specific init: check the clock, grab/config pins, etc.
         */
        if (pdata->init && pdata->init(pdev)) {
                retval = -ENODEV;
                goto err2;
        }

        /* Enable USB controller, 83xx or 8536 */
        if (pdata->have_sysif_regs && pdata->controller_ver < FSL_USB_VER_1_6) {
                tmp = ioread32be(hcd->regs + FSL_SOC_USB_CTRL);
                tmp &= ~CONTROL_REGISTER_W1C_MASK;
                tmp |= 0x4;
                iowrite32be(tmp, hcd->regs + FSL_SOC_USB_CTRL);
        }

        /* Set USB_EN bit to select ULPI phy for USB controller version 2.5 */
        if (pdata->controller_ver == FSL_USB_VER_2_5 &&
            pdata->phy_mode == FSL_USB2_PHY_ULPI)
                iowrite32be(USB_CTRL_USB_EN, hcd->regs + FSL_SOC_USB_CTRL);

        /*
         * Enable UTMI phy and program PTS field in UTMI mode before asserting
         * controller reset for USB Controller version 2.5
         */
        if (pdata->has_fsl_erratum_a007792) {
                tmp = ioread32be(hcd->regs + FSL_SOC_USB_CTRL);
                tmp &= ~CONTROL_REGISTER_W1C_MASK;
                tmp |= CTRL_UTMI_PHY_EN;
                iowrite32be(tmp, hcd->regs + FSL_SOC_USB_CTRL);

                writel(PORT_PTS_UTMI, hcd->regs + FSL_SOC_USB_PORTSC1);
        }

        /* Don't need to set host mode here. It will be done by tdi_reset() */

        retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (retval != 0)
                goto err2;
        device_wakeup_enable(hcd->self.controller);

#ifdef CONFIG_USB_OTG
        if (pdata->operating_mode == FSL_USB2_DR_OTG) {
                struct ehci_hcd *ehci = hcd_to_ehci(hcd);

                hcd->usb_phy = usb_get_phy(USB_PHY_TYPE_USB2);
                dev_dbg(&pdev->dev, "hcd=0x%p  ehci=0x%p, phy=0x%p\n",
                        hcd, ehci, hcd->usb_phy);

                if (!IS_ERR_OR_NULL(hcd->usb_phy)) {
                        retval = otg_set_host(hcd->usb_phy->otg,
                                              &ehci_to_hcd(ehci)->self);
                        if (retval) {
                                usb_put_phy(hcd->usb_phy);
                                goto err2;
                        }
                } else {
                        dev_err(&pdev->dev, "can't find phy\n");
                        retval = -ENODEV;
                        goto err2;
                }

                hcd->skip_phy_initialization = 1;
        }
#endif
        return retval;

      err2:
        usb_put_hcd(hcd);
      err1:
        dev_err(&pdev->dev, "init %s fail, %d\n", dev_name(&pdev->dev), retval);
        if (pdata->exit)
                pdata->exit(pdev);
        return retval;
}

static bool usb_phy_clk_valid(struct usb_hcd *hcd)
{
        void __iomem *non_ehci = hcd->regs;
        bool ret = true;

        if (!(ioread32be(non_ehci + FSL_SOC_USB_CTRL) & PHY_CLK_VALID))
                ret = false;

        return ret;
}

static int ehci_fsl_setup_phy(struct usb_hcd *hcd,
                               enum fsl_usb2_phy_modes phy_mode,
                               unsigned int port_offset)
{
        u32 portsc, tmp;
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        void __iomem *non_ehci = hcd->regs;
        struct device *dev = hcd->self.controller;
        struct fsl_usb2_platform_data *pdata = dev_get_platdata(dev);

        if (pdata->controller_ver < 0) {
                dev_warn(hcd->self.controller, "Could not get controller version\n");
                return -ENODEV;
        }

        portsc = ehci_readl(ehci, &ehci->regs->port_status[port_offset]);
        portsc &= ~(PORT_PTS_MSK | PORT_PTS_PTW);

        switch (phy_mode) {
        case FSL_USB2_PHY_ULPI:
                if (pdata->have_sysif_regs && pdata->controller_ver) {
                        /* controller version 1.6 or above */
                        /* turn off UTMI PHY first */
                        tmp = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
                        tmp &= ~(CONTROL_REGISTER_W1C_MASK | UTMI_PHY_EN);
                        iowrite32be(tmp, non_ehci + FSL_SOC_USB_CTRL);

                        /* then turn on ULPI and enable USB controller */
                        tmp = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
                        tmp &= ~CONTROL_REGISTER_W1C_MASK;
                        tmp |= ULPI_PHY_CLK_SEL | USB_CTRL_USB_EN;
                        iowrite32be(tmp, non_ehci + FSL_SOC_USB_CTRL);
                }
                portsc |= PORT_PTS_ULPI;
                break;
        case FSL_USB2_PHY_SERIAL:
                portsc |= PORT_PTS_SERIAL;
                break;
        case FSL_USB2_PHY_UTMI_WIDE:
                portsc |= PORT_PTS_PTW;
                fallthrough;
        case FSL_USB2_PHY_UTMI:
                /* Presence of this node "has_fsl_erratum_a006918"
                 * in device-tree is used to stop USB controller
                 * initialization in Linux
                 */
                if (pdata->has_fsl_erratum_a006918) {
                        dev_warn(dev, "USB PHY clock invalid\n");
                        return -EINVAL;
                }
                fallthrough;
        case FSL_USB2_PHY_UTMI_DUAL:
                /* PHY_CLK_VALID bit is de-featured from all controller
                 * versions below 2.4 and is to be checked only for
                 * internal UTMI phy
                 */
                if (pdata->controller_ver > FSL_USB_VER_2_4 &&
                    pdata->have_sysif_regs && !usb_phy_clk_valid(hcd)) {
                        dev_err(dev, "USB PHY clock invalid\n");
                        return -EINVAL;
                }

                if (pdata->have_sysif_regs && pdata->controller_ver) {
                        /* controller version 1.6 or above */
                        tmp = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
                        tmp &= ~CONTROL_REGISTER_W1C_MASK;
                        tmp |= UTMI_PHY_EN;
                        iowrite32be(tmp, non_ehci + FSL_SOC_USB_CTRL);

                        mdelay(FSL_UTMI_PHY_DLY);  /* Delay for UTMI PHY CLK to
                                                become stable - 10ms*/
                }
                /* enable UTMI PHY */
                if (pdata->have_sysif_regs) {
                        tmp = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
                        tmp &= ~CONTROL_REGISTER_W1C_MASK;
                        tmp |= CTRL_UTMI_PHY_EN;
                        iowrite32be(tmp, non_ehci + FSL_SOC_USB_CTRL);
                }
                portsc |= PORT_PTS_UTMI;
                break;
        case FSL_USB2_PHY_NONE:
                break;
        }

        if (pdata->have_sysif_regs &&
            pdata->controller_ver > FSL_USB_VER_1_6 &&
            !usb_phy_clk_valid(hcd)) {
                dev_warn(hcd->self.controller, "USB PHY clock invalid\n");
                return -EINVAL;
        }

        ehci_writel(ehci, portsc, &ehci->regs->port_status[port_offset]);

        if (phy_mode != FSL_USB2_PHY_ULPI && pdata->have_sysif_regs) {
                tmp = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
                tmp &= ~CONTROL_REGISTER_W1C_MASK;
                tmp |= USB_CTRL_USB_EN;
                iowrite32be(tmp, non_ehci + FSL_SOC_USB_CTRL);
        }

        return 0;
}

static int ehci_fsl_usb_setup(struct ehci_hcd *ehci)
{
        struct usb_hcd *hcd = ehci_to_hcd(ehci);
        struct fsl_usb2_platform_data *pdata;
        void __iomem *non_ehci = hcd->regs;

        pdata = dev_get_platdata(hcd->self.controller);

        if (pdata->have_sysif_regs) {
                /*
                * Turn on cache snooping hardware, since some PowerPC platforms
                * wholly rely on hardware to deal with cache coherent
                */

                /* Setup Snooping for all the 4GB space */
                /* SNOOP1 starts from 0x0, size 2G */
                iowrite32be(0x0 | SNOOP_SIZE_2GB,
                            non_ehci + FSL_SOC_USB_SNOOP1);
                /* SNOOP2 starts from 0x80000000, size 2G */
                iowrite32be(0x80000000 | SNOOP_SIZE_2GB,
                            non_ehci + FSL_SOC_USB_SNOOP2);
        }

        /* Deal with USB erratum A-005275 */
        if (pdata->has_fsl_erratum_a005275 == 1)
                ehci->has_fsl_hs_errata = 1;

        if (pdata->has_fsl_erratum_a005697 == 1)
                ehci->has_fsl_susp_errata = 1;

        if ((pdata->operating_mode == FSL_USB2_DR_HOST) ||
                        (pdata->operating_mode == FSL_USB2_DR_OTG))
                if (ehci_fsl_setup_phy(hcd, pdata->phy_mode, 0))
                        return -EINVAL;

        if (pdata->operating_mode == FSL_USB2_MPH_HOST) {

                /* Deal with USB Erratum #14 on MPC834x Rev 1.0 & 1.1 chips */
                if (pdata->has_fsl_erratum_14 == 1)
                        ehci->has_fsl_port_bug = 1;

                if (pdata->port_enables & FSL_USB2_PORT0_ENABLED)
                        if (ehci_fsl_setup_phy(hcd, pdata->phy_mode, 0))
                                return -EINVAL;

                if (pdata->port_enables & FSL_USB2_PORT1_ENABLED)
                        if (ehci_fsl_setup_phy(hcd, pdata->phy_mode, 1))
                                return -EINVAL;
        }

        if (pdata->have_sysif_regs) {
#ifdef CONFIG_FSL_SOC_BOOKE
                iowrite32be(0x00000008, non_ehci + FSL_SOC_USB_PRICTRL);
                iowrite32be(0x00000080, non_ehci + FSL_SOC_USB_AGECNTTHRSH);
#else
                iowrite32be(0x0000000c, non_ehci + FSL_SOC_USB_PRICTRL);
                iowrite32be(0x00000040, non_ehci + FSL_SOC_USB_AGECNTTHRSH);
#endif
                iowrite32be(0x00000001, non_ehci + FSL_SOC_USB_SICTRL);
        }

        return 0;
}

/* called after powerup, by probe or system-pm "wakeup" */
static int ehci_fsl_reinit(struct ehci_hcd *ehci)
{
        if (ehci_fsl_usb_setup(ehci))
                return -EINVAL;

        return 0;
}

/* called during probe() after chip reset completes */
static int ehci_fsl_setup(struct usb_hcd *hcd)
{
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        int retval;
        struct fsl_usb2_platform_data *pdata;
        struct device *dev;

        dev = hcd->self.controller;
        pdata = dev_get_platdata(hcd->self.controller);
        ehci->big_endian_desc = pdata->big_endian_desc;
        ehci->big_endian_mmio = pdata->big_endian_mmio;

        /* EHCI registers start at offset 0x100 */
        ehci->caps = hcd->regs + 0x100;

#if defined(CONFIG_PPC_83xx) || defined(CONFIG_PPC_85xx)
        /*
         * Deal with MPC834X/85XX that need port power to be cycled
         * after the power fault condition is removed. Otherwise the
         * state machine does not reflect PORTSC[CSC] correctly.
         */
        ehci->need_oc_pp_cycle = 1;
#endif

        hcd->has_tt = 1;

        retval = ehci_setup(hcd);
        if (retval)
                return retval;

        if (of_device_is_compatible(dev->parent->of_node,
                                    "fsl,mpc5121-usb2-dr")) {
                /*
                 * set SBUSCFG:AHBBRST so that control msgs don't
                 * fail when doing heavy PATA writes.
                 */
                ehci_writel(ehci, SBUSCFG_INCR8,
                            hcd->regs + FSL_SOC_USB_SBUSCFG);
        }

        retval = ehci_fsl_reinit(ehci);
        return retval;
}

struct ehci_fsl_priv {
        /* Saved USB PHY settings, need to restore after deep sleep. */
        u32 usb_ctrl;
};

#define hcd_to_ehci_fsl_priv(h) ((struct ehci_fsl_priv *) hcd_to_ehci(h)->priv)

#ifdef CONFIG_PM

#ifdef CONFIG_PPC_MPC512x
static int ehci_fsl_mpc512x_drv_suspend(struct device *dev)
{
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        struct fsl_usb2_platform_data *pdata = dev_get_platdata(dev);
        u32 tmp;

#ifdef CONFIG_DYNAMIC_DEBUG
        u32 mode = ehci_readl(ehci, hcd->regs + FSL_SOC_USB_USBMODE);
        mode &= USBMODE_CM_MASK;
        tmp = ehci_readl(ehci, hcd->regs + 0x140);      /* usbcmd */

        dev_dbg(dev, "suspend=%d already_suspended=%d "
                "mode=%d  usbcmd %08x\n", pdata->suspended,
                pdata->already_suspended, mode, tmp);
#endif

        /*
         * If the controller is already suspended, then this must be a
         * PM suspend.  Remember this fact, so that we will leave the
         * controller suspended at PM resume time.
         */
        if (pdata->suspended) {
                dev_dbg(dev, "already suspended, leaving early\n");
                pdata->already_suspended = 1;
                return 0;
        }

        dev_dbg(dev, "suspending...\n");

        ehci->rh_state = EHCI_RH_SUSPENDED;
        dev->power.power_state = PMSG_SUSPEND;

        /* ignore non-host interrupts */
        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

        /* stop the controller */
        tmp = ehci_readl(ehci, &ehci->regs->command);
        tmp &= ~CMD_RUN;
        ehci_writel(ehci, tmp, &ehci->regs->command);

        /* save EHCI registers */
        pdata->pm_command = ehci_readl(ehci, &ehci->regs->command);
        pdata->pm_command &= ~CMD_RUN;
        pdata->pm_status  = ehci_readl(ehci, &ehci->regs->status);
        pdata->pm_intr_enable  = ehci_readl(ehci, &ehci->regs->intr_enable);
        pdata->pm_frame_index  = ehci_readl(ehci, &ehci->regs->frame_index);
        pdata->pm_segment  = ehci_readl(ehci, &ehci->regs->segment);
        pdata->pm_frame_list  = ehci_readl(ehci, &ehci->regs->frame_list);
        pdata->pm_async_next  = ehci_readl(ehci, &ehci->regs->async_next);
        pdata->pm_configured_flag  =
                ehci_readl(ehci, &ehci->regs->configured_flag);
        pdata->pm_portsc = ehci_readl(ehci, &ehci->regs->port_status[0]);
        pdata->pm_usbgenctrl = ehci_readl(ehci,
                                          hcd->regs + FSL_SOC_USB_USBGENCTRL);

        /* clear the W1C bits */
        pdata->pm_portsc &= cpu_to_hc32(ehci, ~PORT_RWC_BITS);

        pdata->suspended = 1;

        /* clear PP to cut power to the port */
        tmp = ehci_readl(ehci, &ehci->regs->port_status[0]);
        tmp &= ~PORT_POWER;
        ehci_writel(ehci, tmp, &ehci->regs->port_status[0]);

        return 0;
}

static int ehci_fsl_mpc512x_drv_resume(struct device *dev)
{
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        struct fsl_usb2_platform_data *pdata = dev_get_platdata(dev);
        u32 tmp;

        dev_dbg(dev, "suspend=%d already_suspended=%d\n",
                pdata->suspended, pdata->already_suspended);

        /*
         * If the controller was already suspended at suspend time,
         * then don't resume it now.
         */
        if (pdata->already_suspended) {
                dev_dbg(dev, "already suspended, leaving early\n");
                pdata->already_suspended = 0;
                return 0;
        }

        if (!pdata->suspended) {
                dev_dbg(dev, "not suspended, leaving early\n");
                return 0;
        }

        pdata->suspended = 0;

        dev_dbg(dev, "resuming...\n");

        /* set host mode */
        tmp = USBMODE_CM_HOST | (pdata->es ? USBMODE_ES : 0);
        ehci_writel(ehci, tmp, hcd->regs + FSL_SOC_USB_USBMODE);

        ehci_writel(ehci, pdata->pm_usbgenctrl,
                    hcd->regs + FSL_SOC_USB_USBGENCTRL);
        ehci_writel(ehci, ISIPHYCTRL_PXE | ISIPHYCTRL_PHYE,
                    hcd->regs + FSL_SOC_USB_ISIPHYCTRL);

        ehci_writel(ehci, SBUSCFG_INCR8, hcd->regs + FSL_SOC_USB_SBUSCFG);

        /* restore EHCI registers */
        ehci_writel(ehci, pdata->pm_command, &ehci->regs->command);
        ehci_writel(ehci, pdata->pm_intr_enable, &ehci->regs->intr_enable);
        ehci_writel(ehci, pdata->pm_frame_index, &ehci->regs->frame_index);
        ehci_writel(ehci, pdata->pm_segment, &ehci->regs->segment);
        ehci_writel(ehci, pdata->pm_frame_list, &ehci->regs->frame_list);
        ehci_writel(ehci, pdata->pm_async_next, &ehci->regs->async_next);
        ehci_writel(ehci, pdata->pm_configured_flag,
                    &ehci->regs->configured_flag);
        ehci_writel(ehci, pdata->pm_portsc, &ehci->regs->port_status[0]);

        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
        ehci->rh_state = EHCI_RH_RUNNING;
        dev->power.power_state = PMSG_ON;

        tmp = ehci_readl(ehci, &ehci->regs->command);
        tmp |= CMD_RUN;
        ehci_writel(ehci, tmp, &ehci->regs->command);

        usb_hcd_resume_root_hub(hcd);

        return 0;
}
#else
static inline int ehci_fsl_mpc512x_drv_suspend(struct device *dev)
{
        return 0;
}

static inline int ehci_fsl_mpc512x_drv_resume(struct device *dev)
{
        return 0;
}
#endif /* CONFIG_PPC_MPC512x */

static int ehci_fsl_drv_suspend(struct device *dev)
{
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct ehci_fsl_priv *priv = hcd_to_ehci_fsl_priv(hcd);
        void __iomem *non_ehci = hcd->regs;

        if (of_device_is_compatible(dev->parent->of_node,
                                    "fsl,mpc5121-usb2-dr")) {
                return ehci_fsl_mpc512x_drv_suspend(dev);
        }

        ehci_prepare_ports_for_controller_suspend(hcd_to_ehci(hcd),
                        device_may_wakeup(dev));
        if (!fsl_deep_sleep())
                return 0;

        priv->usb_ctrl = ioread32be(non_ehci + FSL_SOC_USB_CTRL);
        return 0;
}

static int ehci_fsl_drv_resume(struct device *dev)
{
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct ehci_fsl_priv *priv = hcd_to_ehci_fsl_priv(hcd);
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        void __iomem *non_ehci = hcd->regs;

        if (of_device_is_compatible(dev->parent->of_node,
                                    "fsl,mpc5121-usb2-dr")) {
                return ehci_fsl_mpc512x_drv_resume(dev);
        }

        ehci_prepare_ports_for_controller_resume(ehci);
        if (!fsl_deep_sleep())
                return 0;

        usb_root_hub_lost_power(hcd->self.root_hub);

        /* Restore USB PHY settings and enable the controller. */
        iowrite32be(priv->usb_ctrl, non_ehci + FSL_SOC_USB_CTRL);

        ehci_reset(ehci);
        ehci_fsl_reinit(ehci);

        return 0;
}

static int ehci_fsl_drv_restore(struct device *dev)
{
        struct usb_hcd *hcd = dev_get_drvdata(dev);

        usb_root_hub_lost_power(hcd->self.root_hub);
        return 0;
}

static const struct dev_pm_ops ehci_fsl_pm_ops = {
        .suspend = ehci_fsl_drv_suspend,
        .resume = ehci_fsl_drv_resume,
        .restore = ehci_fsl_drv_restore,
};

#define EHCI_FSL_PM_OPS         (&ehci_fsl_pm_ops)
#else
#define EHCI_FSL_PM_OPS         NULL
#endif /* CONFIG_PM */

#ifdef CONFIG_USB_OTG
static int ehci_start_port_reset(struct usb_hcd *hcd, unsigned port)
{
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        u32 status;

        if (!port)
                return -EINVAL;

        port--;

        /* start port reset before HNP protocol time out */
        status = readl(&ehci->regs->port_status[port]);
        if (!(status & PORT_CONNECT))
                return -ENODEV;

        /* hub_wq will finish the reset later */
        if (ehci_is_TDI(ehci)) {
                writel(PORT_RESET |
                       (status & ~(PORT_CSC | PORT_PEC | PORT_OCC)),
                       &ehci->regs->port_status[port]);
        } else {
                writel(PORT_RESET, &ehci->regs->port_status[port]);
        }

        return 0;
}
#else
#define ehci_start_port_reset   NULL
#endif /* CONFIG_USB_OTG */

static const struct ehci_driver_overrides ehci_fsl_overrides __initconst = {
        .extra_priv_size = sizeof(struct ehci_fsl_priv),
        .reset = ehci_fsl_setup,
};

/**
 * fsl_ehci_drv_remove - shutdown processing for FSL-based HCDs
 * @pdev: USB Host Controller being removed
 *
 * Context: task context, might sleep
 *
 * Reverses the effect of usb_hcd_fsl_probe().
 */
static void fsl_ehci_drv_remove(struct platform_device *pdev)
{
        struct fsl_usb2_platform_data *pdata = dev_get_platdata(&pdev->dev);
        struct usb_hcd *hcd = platform_get_drvdata(pdev);

        if (!IS_ERR_OR_NULL(hcd->usb_phy)) {
                otg_set_host(hcd->usb_phy->otg, NULL);
                usb_put_phy(hcd->usb_phy);
        }

        usb_remove_hcd(hcd);

        /*
         * do platform specific un-initialization:
         * release iomux pins, disable clock, etc.
         */
        if (pdata->exit)
                pdata->exit(pdev);
        usb_put_hcd(hcd);
}

static struct platform_driver ehci_fsl_driver = {
        .probe = fsl_ehci_drv_probe,
        .remove = fsl_ehci_drv_remove,
        .shutdown = usb_hcd_platform_shutdown,
        .driver = {
                .name = DRV_NAME,
                .pm = EHCI_FSL_PM_OPS,
        },
};

static int __init ehci_fsl_init(void)
{
        if (usb_disabled())
                return -ENODEV;

        ehci_init_driver(&fsl_ehci_hc_driver, &ehci_fsl_overrides);

        fsl_ehci_hc_driver.product_desc =
                        "Freescale On-Chip EHCI Host Controller";
        fsl_ehci_hc_driver.start_port_reset = ehci_start_port_reset;


        return platform_driver_register(&ehci_fsl_driver);
}
module_init(ehci_fsl_init);

static void __exit ehci_fsl_cleanup(void)
{
        platform_driver_unregister(&ehci_fsl_driver);
}
module_exit(ehci_fsl_cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);