/*
 * Copyright (C) 2001-2004 by David Brownell
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* this file is part of ehci-hcd.c */

/*-------------------------------------------------------------------------*/

/*
 * EHCI Root Hub ... the nonsharable stuff
 *
 * Registers don't need cpu_to_le32, that happens transparently
 */

/*-------------------------------------------------------------------------*/
#include <linux/usb/otg.h>

#define PORT_WAKE_BITS  (PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E)

#ifdef  CONFIG_PM

static int ehci_hub_control(
        struct usb_hcd  *hcd,
        u16             typeReq,
        u16             wValue,
        u16             wIndex,
        char            *buf,
        u16             wLength
);

static int persist_enabled_on_companion(struct usb_device *udev, void *unused)
{
        return !udev->maxchild && udev->persist_enabled &&
                udev->bus->root_hub->speed < USB_SPEED_HIGH;
}

/* After a power loss, ports that were owned by the companion must be
 * reset so that the companion can still own them.
 */
static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
{
        u32 __iomem     *reg;
        u32             status;
        int             port;
        __le32          buf;
        struct usb_hcd  *hcd = ehci_to_hcd(ehci);

        if (!ehci->owned_ports)
                return;

        /*
         * USB 1.1 devices are mostly HIDs, which don't need to persist across
         * suspends. If we ensure that none of our companion's devices have
         * persist_enabled (by looking through all USB 1.1 buses in the system),
         * we can skip this and avoid slowing resume down. Devices without
         * persist will just get reenumerated shortly after resume anyway.
         */
        if (!usb_for_each_dev(NULL, persist_enabled_on_companion))
                return;

        /* Make sure the ports are powered */
        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                if (test_bit(port, &ehci->owned_ports)) {
                        reg = &ehci->regs->port_status[port];
                        status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
                        if (!(status & PORT_POWER)) {
                                status |= PORT_POWER;
                                ehci_writel(ehci, status, reg);
                        }
                }
        }

        /* Give the connections some time to appear */
        msleep(20);

        spin_lock_irq(&ehci->lock);
        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                if (test_bit(port, &ehci->owned_ports)) {
                        reg = &ehci->regs->port_status[port];
                        status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;

                        /* Port already owned by companion? */
                        if (status & PORT_OWNER)
                                clear_bit(port, &ehci->owned_ports);
                        else if (test_bit(port, &ehci->companion_ports))
                                ehci_writel(ehci, status & ~PORT_PE, reg);
                        else {
                                spin_unlock_irq(&ehci->lock);
                                ehci_hub_control(hcd, SetPortFeature,
                                                USB_PORT_FEAT_RESET, port + 1,
                                                NULL, 0);
                                spin_lock_irq(&ehci->lock);
                        }
                }
        }
        spin_unlock_irq(&ehci->lock);

        if (!ehci->owned_ports)
                return;
        msleep(90);             /* Wait for resets to complete */

        spin_lock_irq(&ehci->lock);
        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                if (test_bit(port, &ehci->owned_ports)) {
                        spin_unlock_irq(&ehci->lock);
                        ehci_hub_control(hcd, GetPortStatus,
                                        0, port + 1,
                                        (char *) &buf, sizeof(buf));
                        spin_lock_irq(&ehci->lock);

                        /* The companion should now own the port,
                         * but if something went wrong the port must not
                         * remain enabled.
                         */
                        reg = &ehci->regs->port_status[port];
                        status = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
                        if (status & PORT_OWNER)
                                ehci_writel(ehci, status | PORT_CSC, reg);
                        else {
                                ehci_dbg(ehci, "failed handover port %d: %x\n",
                                                port + 1, status);
                                ehci_writel(ehci, status & ~PORT_PE, reg);
                        }
                }
        }

        ehci->owned_ports = 0;
        spin_unlock_irq(&ehci->lock);
}

static int ehci_port_change(struct ehci_hcd *ehci)
{
        int i = HCS_N_PORTS(ehci->hcs_params);

        /* First check if the controller indicates a change event */

        if (ehci_readl(ehci, &ehci->regs->status) & STS_PCD)
                return 1;

        /*
         * Not all controllers appear to update this while going from D3 to D0,
         * so check the individual port status registers as well
         */

        while (i--)
                if (ehci_readl(ehci, &ehci->regs->port_status[i]) & PORT_CSC)
                        return 1;

        return 0;
}

static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
                bool suspending, bool do_wakeup)
{
        int             port;
        u32             temp;

        /* If remote wakeup is enabled for the root hub but disabled
         * for the controller, we must adjust all the port wakeup flags
         * when the controller is suspended or resumed.  In all other
         * cases they don't need to be changed.
         */
        if (!ehci_to_hcd(ehci)->self.root_hub->do_remote_wakeup || do_wakeup)
                return;

        spin_lock_irq(&ehci->lock);

        /* clear phy low-power mode before changing wakeup flags */
        if (ehci->has_hostpc) {
                port = HCS_N_PORTS(ehci->hcs_params);
                while (port--) {
                        u32 __iomem     *hostpc_reg = &ehci->regs->hostpc[port];

                        temp = ehci_readl(ehci, hostpc_reg);
                        ehci_writel(ehci, temp & ~HOSTPC_PHCD, hostpc_reg);
                }
                spin_unlock_irq(&ehci->lock);
                msleep(5);
                spin_lock_irq(&ehci->lock);
        }

        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                u32 __iomem     *reg = &ehci->regs->port_status[port];
                u32             t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
                u32             t2 = t1 & ~PORT_WAKE_BITS;

                /* If we are suspending the controller, clear the flags.
                 * If we are resuming the controller, set the wakeup flags.
                 */
                if (!suspending) {
                        if (t1 & PORT_CONNECT)
                                t2 |= PORT_WKOC_E | PORT_WKDISC_E;
                        else
                                t2 |= PORT_WKOC_E | PORT_WKCONN_E;
                }
                ehci_vdbg(ehci, "port %d, %08x -> %08x\n",
                                port + 1, t1, t2);
                ehci_writel(ehci, t2, reg);
        }

        /* enter phy low-power mode again */
        if (ehci->has_hostpc) {
                port = HCS_N_PORTS(ehci->hcs_params);
                while (port--) {
                        u32 __iomem     *hostpc_reg = &ehci->regs->hostpc[port];

                        temp = ehci_readl(ehci, hostpc_reg);
                        ehci_writel(ehci, temp | HOSTPC_PHCD, hostpc_reg);
                }
        }

        /* Does the root hub have a port wakeup pending? */
        if (!suspending && ehci_port_change(ehci))
                usb_hcd_resume_root_hub(ehci_to_hcd(ehci));

        spin_unlock_irq(&ehci->lock);
}

static int ehci_bus_suspend (struct usb_hcd *hcd)
{
        struct ehci_hcd         *ehci = hcd_to_ehci (hcd);
        int                     port;
        int                     mask;
        int                     changed;

        ehci_dbg(ehci, "suspend root hub\n");

        if (time_before (jiffies, ehci->next_statechange))
                msleep(5);

        /* stop the schedules */
        ehci_quiesce(ehci);

        spin_lock_irq (&ehci->lock);
        if (ehci->rh_state < EHCI_RH_RUNNING)
                goto done;

        /* Once the controller is stopped, port resumes that are already
         * in progress won't complete.  Hence if remote wakeup is enabled
         * for the root hub and any ports are in the middle of a resume or
         * remote wakeup, we must fail the suspend.
         */
        if (hcd->self.root_hub->do_remote_wakeup) {
                if (ehci->resuming_ports) {
                        spin_unlock_irq(&ehci->lock);
                        ehci_dbg(ehci, "suspend failed because a port is resuming\n");
                        return -EBUSY;
                }
        }

        /* Unlike other USB host controller types, EHCI doesn't have
         * any notion of "global" or bus-wide suspend.  The driver has
         * to manually suspend all the active unsuspended ports, and
         * then manually resume them in the bus_resume() routine.
         */
        ehci->bus_suspended = 0;
        ehci->owned_ports = 0;
        changed = 0;
        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                u32 __iomem     *reg = &ehci->regs->port_status [port];
                u32             t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
                u32             t2 = t1 & ~PORT_WAKE_BITS;

                /* keep track of which ports we suspend */
                if (t1 & PORT_OWNER)
                        set_bit(port, &ehci->owned_ports);
                else if ((t1 & PORT_PE) && !(t1 & PORT_SUSPEND)) {
                        t2 |= PORT_SUSPEND;
                        set_bit(port, &ehci->bus_suspended);
                }

                /* enable remote wakeup on all ports, if told to do so */
                if (hcd->self.root_hub->do_remote_wakeup) {
                        /* only enable appropriate wake bits, otherwise the
                         * hardware can not go phy low power mode. If a race
                         * condition happens here(connection change during bits
                         * set), the port change detection will finally fix it.
                         */
                        if (t1 & PORT_CONNECT)
                                t2 |= PORT_WKOC_E | PORT_WKDISC_E;
                        else
                                t2 |= PORT_WKOC_E | PORT_WKCONN_E;
                }

                if (t1 != t2) {
                        ehci_vdbg (ehci, "port %d, %08x -> %08x\n",
                                port + 1, t1, t2);
                        ehci_writel(ehci, t2, reg);
                        changed = 1;
                }
        }

        if (changed && ehci->has_hostpc) {
                spin_unlock_irq(&ehci->lock);
                msleep(5);      /* 5 ms for HCD to enter low-power mode */
                spin_lock_irq(&ehci->lock);

                port = HCS_N_PORTS(ehci->hcs_params);
                while (port--) {
                        u32 __iomem     *hostpc_reg = &ehci->regs->hostpc[port];
                        u32             t3;

                        t3 = ehci_readl(ehci, hostpc_reg);
                        ehci_writel(ehci, t3 | HOSTPC_PHCD, hostpc_reg);
                        t3 = ehci_readl(ehci, hostpc_reg);
                        ehci_dbg(ehci, "Port %d phy low-power mode %s\n",
                                        port, (t3 & HOSTPC_PHCD) ?
                                        "succeeded" : "failed");
                }
        }
        spin_unlock_irq(&ehci->lock);

        /* Apparently some devices need a >= 1-uframe delay here */
        if (ehci->bus_suspended)
                udelay(150);

        /* turn off now-idle HC */
        ehci_halt (ehci);

        spin_lock_irq(&ehci->lock);
        if (ehci->enabled_hrtimer_events & BIT(EHCI_HRTIMER_POLL_DEAD))
                ehci_handle_controller_death(ehci);
        if (ehci->rh_state != EHCI_RH_RUNNING)
                goto done;
        ehci->rh_state = EHCI_RH_SUSPENDED;

        end_unlink_async(ehci);
        unlink_empty_async_suspended(ehci);
        ehci_handle_intr_unlinks(ehci);
        end_free_itds(ehci);

        /* allow remote wakeup */
        mask = INTR_MASK;
        if (!hcd->self.root_hub->do_remote_wakeup)
                mask &= ~STS_PCD;
        ehci_writel(ehci, mask, &ehci->regs->intr_enable);
        ehci_readl(ehci, &ehci->regs->intr_enable);

 done:
        ehci->next_statechange = jiffies + msecs_to_jiffies(10);
        ehci->enabled_hrtimer_events = 0;
        ehci->next_hrtimer_event = EHCI_HRTIMER_NO_EVENT;
        spin_unlock_irq (&ehci->lock);

        hrtimer_cancel(&ehci->hrtimer);
        return 0;
}


/* caller has locked the root hub, and should reset/reinit on error */
static int ehci_bus_resume (struct usb_hcd *hcd)
{
        struct ehci_hcd         *ehci = hcd_to_ehci (hcd);
        u32                     temp;
        u32                     power_okay;
        int                     i;
        unsigned long           resume_needed = 0;

        if (time_before (jiffies, ehci->next_statechange))
                msleep(5);
        spin_lock_irq (&ehci->lock);
        if (!HCD_HW_ACCESSIBLE(hcd) || ehci->shutdown)
                goto shutdown;

        if (unlikely(ehci->debug)) {
                if (!dbgp_reset_prep(hcd))
                        ehci->debug = NULL;
                else
                        dbgp_external_startup(hcd);
        }

        /* Ideally and we've got a real resume here, and no port's power
         * was lost.  (For PCI, that means Vaux was maintained.)  But we
         * could instead be restoring a swsusp snapshot -- so that BIOS was
         * the last user of the controller, not reset/pm hardware keeping
         * state we gave to it.
         */
        power_okay = ehci_readl(ehci, &ehci->regs->intr_enable);
        ehci_dbg(ehci, "resume root hub%s\n",
                        power_okay ? "" : " after power loss");

        /* at least some APM implementations will try to deliver
         * IRQs right away, so delay them until we're ready.
         */
        ehci_writel(ehci, 0, &ehci->regs->intr_enable);

        /* re-init operational registers */
        ehci_writel(ehci, 0, &ehci->regs->segment);
        ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
        ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next);

        /* restore CMD_RUN, framelist size, and irq threshold */
        ehci->command |= CMD_RUN;
        ehci_writel(ehci, ehci->command, &ehci->regs->command);
        ehci->rh_state = EHCI_RH_RUNNING;

        /*
         * According to Bugzilla #8190, the port status for some controllers
         * will be wrong without a delay. At their wrong status, the port
         * is enabled, but not suspended neither resumed.
         */
        i = HCS_N_PORTS(ehci->hcs_params);
        while (i--) {
                temp = ehci_readl(ehci, &ehci->regs->port_status[i]);
                if ((temp & PORT_PE) &&
                                !(temp & (PORT_SUSPEND | PORT_RESUME))) {
                        ehci_dbg(ehci, "Port status(0x%x) is wrong\n", temp);
                        spin_unlock_irq(&ehci->lock);
                        msleep(8);
                        spin_lock_irq(&ehci->lock);
                        break;
                }
        }

        if (ehci->shutdown)
                goto shutdown;

        /* clear phy low-power mode before resume */
        if (ehci->bus_suspended && ehci->has_hostpc) {
                i = HCS_N_PORTS(ehci->hcs_params);
                while (i--) {
                        if (test_bit(i, &ehci->bus_suspended)) {
                                u32 __iomem     *hostpc_reg =
                                                        &ehci->regs->hostpc[i];

                                temp = ehci_readl(ehci, hostpc_reg);
                                ehci_writel(ehci, temp & ~HOSTPC_PHCD,
                                                hostpc_reg);
                        }
                }
                spin_unlock_irq(&ehci->lock);
                msleep(5);
                spin_lock_irq(&ehci->lock);
                if (ehci->shutdown)
                        goto shutdown;
        }

        /* manually resume the ports we suspended during bus_suspend() */
        i = HCS_N_PORTS (ehci->hcs_params);
        while (i--) {
                temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
                temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
                if (test_bit(i, &ehci->bus_suspended) &&
                                (temp & PORT_SUSPEND)) {
                        temp |= PORT_RESUME;
                        set_bit(i, &resume_needed);
                }
                ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
        }

        /* msleep for 20ms only if code is trying to resume port */
        if (resume_needed) {
                spin_unlock_irq(&ehci->lock);
                msleep(20);
                spin_lock_irq(&ehci->lock);
                if (ehci->shutdown)
                        goto shutdown;
        }

        i = HCS_N_PORTS (ehci->hcs_params);
        while (i--) {
                temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
                if (test_bit(i, &resume_needed)) {
                        temp &= ~(PORT_RWC_BITS | PORT_SUSPEND | PORT_RESUME);
                        ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
                        ehci_vdbg (ehci, "resumed port %d\n", i + 1);
                }
        }

        ehci->next_statechange = jiffies + msecs_to_jiffies(5);
        spin_unlock_irq(&ehci->lock);

        ehci_handover_companion_ports(ehci);

        /* Now we can safely re-enable irqs */
        spin_lock_irq(&ehci->lock);
        if (ehci->shutdown)
                goto shutdown;
        ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
        (void) ehci_readl(ehci, &ehci->regs->intr_enable);
        spin_unlock_irq(&ehci->lock);

        return 0;

 shutdown:
        spin_unlock_irq(&ehci->lock);
        return -ESHUTDOWN;
}

#else

#define ehci_bus_suspend        NULL
#define ehci_bus_resume         NULL

#endif  /* CONFIG_PM */

/*-------------------------------------------------------------------------*/

/*
 * Sets the owner of a port
 */
static void set_owner(struct ehci_hcd *ehci, int portnum, int new_owner)
{
        u32 __iomem             *status_reg;
        u32                     port_status;
        int                     try;

        status_reg = &ehci->regs->port_status[portnum];

        /*
         * The controller won't set the OWNER bit if the port is
         * enabled, so this loop will sometimes require at least two
         * iterations: one to disable the port and one to set OWNER.
         */
        for (try = 4; try > 0; --try) {
                spin_lock_irq(&ehci->lock);
                port_status = ehci_readl(ehci, status_reg);
                if ((port_status & PORT_OWNER) == new_owner
                                || (port_status & (PORT_OWNER | PORT_CONNECT))
                                        == 0)
                        try = 0;
                else {
                        port_status ^= PORT_OWNER;
                        port_status &= ~(PORT_PE | PORT_RWC_BITS);
                        ehci_writel(ehci, port_status, status_reg);
                }
                spin_unlock_irq(&ehci->lock);
                if (try > 1)
                        msleep(5);
        }
}

/*-------------------------------------------------------------------------*/

static int check_reset_complete (
        struct ehci_hcd *ehci,
        int             index,
        u32 __iomem     *status_reg,
        int             port_status
) {
        if (!(port_status & PORT_CONNECT))
                return port_status;

        /* if reset finished and it's still not enabled -- handoff */
        if (!(port_status & PORT_PE)) {

                /* with integrated TT, there's nobody to hand it to! */
                if (ehci_is_TDI(ehci)) {
                        ehci_dbg (ehci,
                                "Failed to enable port %d on root hub TT\n",
                                index+1);
                        return port_status;
                }

                ehci_dbg (ehci, "port %d full speed --> companion\n",
                        index + 1);

                // what happens if HCS_N_CC(params) == 0 ?
                port_status |= PORT_OWNER;
                port_status &= ~PORT_RWC_BITS;
                ehci_writel(ehci, port_status, status_reg);

                /* ensure 440EPX ohci controller state is operational */
                if (ehci->has_amcc_usb23)
                        set_ohci_hcfs(ehci, 1);
        } else {
                ehci_dbg(ehci, "port %d reset complete, port enabled\n",
                        index + 1);
                /* ensure 440EPx ohci controller state is suspended */
                if (ehci->has_amcc_usb23)
                        set_ohci_hcfs(ehci, 0);
        }

        return port_status;
}

/*-------------------------------------------------------------------------*/


/* build "status change" packet (one or two bytes) from HC registers */

static int
ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
{
        struct ehci_hcd *ehci = hcd_to_ehci (hcd);
        u32             temp, status;
        u32             mask;
        int             ports, i, retval = 1;
        unsigned long   flags;
        u32             ppcd = ~0;

        /* init status to no-changes */
        buf [0] = 0;
        ports = HCS_N_PORTS (ehci->hcs_params);
        if (ports > 7) {
                buf [1] = 0;
                retval++;
        }

        /* Inform the core about resumes-in-progress by returning
         * a non-zero value even if there are no status changes.
         */
        status = ehci->resuming_ports;

        /* Some boards (mostly VIA?) report bogus overcurrent indications,
         * causing massive log spam unless we completely ignore them.  It
         * may be relevant that VIA VT8235 controllers, where PORT_POWER is
         * always set, seem to clear PORT_OCC and PORT_CSC when writing to
         * PORT_POWER; that's surprising, but maybe within-spec.
         */
        if (!ignore_oc)
                mask = PORT_CSC | PORT_PEC | PORT_OCC;
        else
                mask = PORT_CSC | PORT_PEC;
        // PORT_RESUME from hardware ~= PORT_STAT_C_SUSPEND

        /* no hub change reports (bit 0) for now (power, ...) */

        /* port N changes (bit N)? */
        spin_lock_irqsave (&ehci->lock, flags);

        /* get per-port change detect bits */
        if (ehci->has_ppcd)
                ppcd = ehci_readl(ehci, &ehci->regs->status) >> 16;

        for (i = 0; i < ports; i++) {
                /* leverage per-port change bits feature */
                if (ppcd & (1 << i))
                        temp = ehci_readl(ehci, &ehci->regs->port_status[i]);
                else
                        temp = 0;

                /*
                 * Return status information even for ports with OWNER set.
                 * Otherwise khubd wouldn't see the disconnect event when a
                 * high-speed device is switched over to the companion
                 * controller by the user.
                 */

                if ((temp & mask) != 0 || test_bit(i, &ehci->port_c_suspend)
                                || (ehci->reset_done[i] && time_after_eq(
                                        jiffies, ehci->reset_done[i]))) {
                        if (i < 7)
                            buf [0] |= 1 << (i + 1);
                        else
                            buf [1] |= 1 << (i - 7);
                        status = STS_PCD;
                }
        }

        /* If a resume is in progress, make sure it can finish */
        if (ehci->resuming_ports)
                mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(25));

        spin_unlock_irqrestore (&ehci->lock, flags);
        return status ? retval : 0;
}

/*-------------------------------------------------------------------------*/

static void
ehci_hub_descriptor (
        struct ehci_hcd                 *ehci,
        struct usb_hub_descriptor       *desc
) {
        int             ports = HCS_N_PORTS (ehci->hcs_params);
        u16             temp;

        desc->bDescriptorType = 0x29;
        desc->bPwrOn2PwrGood = 10;      /* ehci 1.0, 2.3.9 says 20ms max */
        desc->bHubContrCurrent = 0;

        desc->bNbrPorts = ports;
        temp = 1 + (ports / 8);
        desc->bDescLength = 7 + 2 * temp;

        /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
        memset(&desc->u.hs.DeviceRemovable[0], 0, temp);
        memset(&desc->u.hs.DeviceRemovable[temp], 0xff, temp);

        temp = 0x0008;                  /* per-port overcurrent reporting */
        if (HCS_PPC (ehci->hcs_params))
                temp |= 0x0001;         /* per-port power control */
        else
                temp |= 0x0002;         /* no power switching */
#if 0
// re-enable when we support USB_PORT_FEAT_INDICATOR below.
        if (HCS_INDICATOR (ehci->hcs_params))
                temp |= 0x0080;         /* per-port indicators (LEDs) */
#endif
        desc->wHubCharacteristics = cpu_to_le16(temp);
}

/*-------------------------------------------------------------------------*/

static int ehci_hub_control (
        struct usb_hcd  *hcd,
        u16             typeReq,
        u16             wValue,
        u16             wIndex,
        char            *buf,
        u16             wLength
) {
        struct ehci_hcd *ehci = hcd_to_ehci (hcd);
        int             ports = HCS_N_PORTS (ehci->hcs_params);
        u32 __iomem     *status_reg = &ehci->regs->port_status[
                                (wIndex & 0xff) - 1];
        u32 __iomem     *hostpc_reg = &ehci->regs->hostpc[(wIndex & 0xff) - 1];
        u32             temp, temp1, status;
        unsigned long   flags;
        int             retval = 0;
        unsigned        selector;

        /*
         * FIXME:  support SetPortFeatures USB_PORT_FEAT_INDICATOR.
         * HCS_INDICATOR may say we can change LEDs to off/amber/green.
         * (track current state ourselves) ... blink for diagnostics,
         * power, "this is the one", etc.  EHCI spec supports this.
         */

        spin_lock_irqsave (&ehci->lock, flags);
        switch (typeReq) {
        case ClearHubFeature:
                switch (wValue) {
                case C_HUB_LOCAL_POWER:
                case C_HUB_OVER_CURRENT:
                        /* no hub-wide feature/status flags */
                        break;
                default:
                        goto error;
                }
                break;
        case ClearPortFeature:
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                temp = ehci_readl(ehci, status_reg);
                temp &= ~PORT_RWC_BITS;

                /*
                 * Even if OWNER is set, so the port is owned by the
                 * companion controller, khubd needs to be able to clear
                 * the port-change status bits (especially
                 * USB_PORT_STAT_C_CONNECTION).
                 */

                switch (wValue) {
                case USB_PORT_FEAT_ENABLE:
                        ehci_writel(ehci, temp & ~PORT_PE, status_reg);
                        break;
                case USB_PORT_FEAT_C_ENABLE:
                        ehci_writel(ehci, temp | PORT_PEC, status_reg);
                        break;
                case USB_PORT_FEAT_SUSPEND:
                        if (temp & PORT_RESET)
                                goto error;
                        if (ehci->no_selective_suspend)
                                break;
#ifdef CONFIG_USB_OTG
                        if ((hcd->self.otg_port == (wIndex + 1))
                            && hcd->self.b_hnp_enable) {
                                otg_start_hnp(hcd->phy->otg);
                                break;
                        }
#endif
                        if (!(temp & PORT_SUSPEND))
                                break;
                        if ((temp & PORT_PE) == 0)
                                goto error;

                        /* clear phy low-power mode before resume */
                        if (ehci->has_hostpc) {
                                temp1 = ehci_readl(ehci, hostpc_reg);
                                ehci_writel(ehci, temp1 & ~HOSTPC_PHCD,
                                                hostpc_reg);
                                spin_unlock_irqrestore(&ehci->lock, flags);
                                msleep(5);/* wait to leave low-power mode */
                                spin_lock_irqsave(&ehci->lock, flags);
                        }
                        /* resume signaling for 20 msec */
                        temp &= ~PORT_WAKE_BITS;
                        ehci_writel(ehci, temp | PORT_RESUME, status_reg);
                        ehci->reset_done[wIndex] = jiffies
                                        + msecs_to_jiffies(20);
                        break;
                case USB_PORT_FEAT_C_SUSPEND:
                        clear_bit(wIndex, &ehci->port_c_suspend);
                        break;
                case USB_PORT_FEAT_POWER:
                        if (HCS_PPC (ehci->hcs_params))
                                ehci_writel(ehci, temp & ~PORT_POWER,
                                                status_reg);
                        break;
                case USB_PORT_FEAT_C_CONNECTION:
                        ehci_writel(ehci, temp | PORT_CSC, status_reg);
                        break;
                case USB_PORT_FEAT_C_OVER_CURRENT:
                        ehci_writel(ehci, temp | PORT_OCC, status_reg);
                        break;
                case USB_PORT_FEAT_C_RESET:
                        /* GetPortStatus clears reset */
                        break;
                default:
                        goto error;
                }
                ehci_readl(ehci, &ehci->regs->command); /* unblock posted write */
                break;
        case GetHubDescriptor:
                ehci_hub_descriptor (ehci, (struct usb_hub_descriptor *)
                        buf);
                break;
        case GetHubStatus:
                /* no hub-wide feature/status flags */
                memset (buf, 0, 4);
                //cpu_to_le32s ((u32 *) buf);
                break;
        case GetPortStatus:
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                status = 0;
                temp = ehci_readl(ehci, status_reg);

                // wPortChange bits
                if (temp & PORT_CSC)
                        status |= USB_PORT_STAT_C_CONNECTION << 16;
                if (temp & PORT_PEC)
                        status |= USB_PORT_STAT_C_ENABLE << 16;

                if ((temp & PORT_OCC) && !ignore_oc){
                        status |= USB_PORT_STAT_C_OVERCURRENT << 16;

                        /*
                         * Hubs should disable port power on over-current.
                         * However, not all EHCI implementations do this
                         * automatically, even if they _do_ support per-port
                         * power switching; they're allowed to just limit the
                         * current.  khubd will turn the power back on.
                         */
                        if (((temp & PORT_OC) || (ehci->need_oc_pp_cycle))
                                        && HCS_PPC(ehci->hcs_params)) {
                                ehci_writel(ehci,
                                        temp & ~(PORT_RWC_BITS | PORT_POWER),
                                        status_reg);
                                temp = ehci_readl(ehci, status_reg);
                        }
                }

                /* whoever resumes must GetPortStatus to complete it!! */
                if (temp & PORT_RESUME) {

                        /* Remote Wakeup received? */
                        if (!ehci->reset_done[wIndex]) {
                                /* resume signaling for 20 msec */
                                ehci->reset_done[wIndex] = jiffies
                                                + msecs_to_jiffies(20);
                                usb_hcd_start_port_resume(&hcd->self, wIndex);
                                set_bit(wIndex, &ehci->resuming_ports);
                                /* check the port again */
                                mod_timer(&ehci_to_hcd(ehci)->rh_timer,
                                                ehci->reset_done[wIndex]);
                        }

                        /* resume completed? */
                        else if (time_after_eq(jiffies,
                                        ehci->reset_done[wIndex])) {
                                clear_bit(wIndex, &ehci->suspended_ports);
                                set_bit(wIndex, &ehci->port_c_suspend);
                                ehci->reset_done[wIndex] = 0;
                                usb_hcd_end_port_resume(&hcd->self, wIndex);

                                /* stop resume signaling */
                                temp &= ~(PORT_RWC_BITS |
                                                PORT_SUSPEND | PORT_RESUME);
                                ehci_writel(ehci, temp, status_reg);
                                clear_bit(wIndex, &ehci->resuming_ports);
                                retval = ehci_handshake(ehci, status_reg,
                                           PORT_RESUME, 0, 2000 /* 2msec */);
                                if (retval != 0) {
                                        ehci_err(ehci,
                                                "port %d resume error %d\n",
                                                wIndex + 1, retval);
                                        goto error;
                                }
                                temp = ehci_readl(ehci, status_reg);
                        }
                }

                /* whoever resets must GetPortStatus to complete it!! */
                if ((temp & PORT_RESET)
                                && time_after_eq(jiffies,
                                        ehci->reset_done[wIndex])) {
                        status |= USB_PORT_STAT_C_RESET << 16;
                        ehci->reset_done [wIndex] = 0;
                        clear_bit(wIndex, &ehci->resuming_ports);

                        /* force reset to complete */
                        ehci_writel(ehci, temp & ~(PORT_RWC_BITS | PORT_RESET),
                                        status_reg);
                        /* REVISIT:  some hardware needs 550+ usec to clear
                         * this bit; seems too long to spin routinely...
                         */
                        retval = ehci_handshake(ehci, status_reg,
                                        PORT_RESET, 0, 1000);
                        if (retval != 0) {
                                ehci_err (ehci, "port %d reset error %d\n",
                                        wIndex + 1, retval);
                                goto error;
                        }

                        /* see what we found out */
                        temp = check_reset_complete (ehci, wIndex, status_reg,
                                        ehci_readl(ehci, status_reg));
                }

                if (!(temp & (PORT_RESUME|PORT_RESET))) {
                        ehci->reset_done[wIndex] = 0;
                        clear_bit(wIndex, &ehci->resuming_ports);
                }

                /* transfer dedicated ports to the companion hc */
                if ((temp & PORT_CONNECT) &&
                                test_bit(wIndex, &ehci->companion_ports)) {
                        temp &= ~PORT_RWC_BITS;
                        temp |= PORT_OWNER;
                        ehci_writel(ehci, temp, status_reg);
                        ehci_dbg(ehci, "port %d --> companion\n", wIndex + 1);
                        temp = ehci_readl(ehci, status_reg);
                }

                /*
                 * Even if OWNER is set, there's no harm letting khubd
                 * see the wPortStatus values (they should all be 0 except
                 * for PORT_POWER anyway).
                 */

                if (temp & PORT_CONNECT) {
                        status |= USB_PORT_STAT_CONNECTION;
                        // status may be from integrated TT
                        if (ehci->has_hostpc) {
                                temp1 = ehci_readl(ehci, hostpc_reg);
                                status |= ehci_port_speed(ehci, temp1);
                        } else
                                status |= ehci_port_speed(ehci, temp);
                }
                if (temp & PORT_PE)
                        status |= USB_PORT_STAT_ENABLE;

                /* maybe the port was unsuspended without our knowledge */
                if (temp & (PORT_SUSPEND|PORT_RESUME)) {
                        status |= USB_PORT_STAT_SUSPEND;
                } else if (test_bit(wIndex, &ehci->suspended_ports)) {
                        clear_bit(wIndex, &ehci->suspended_ports);
                        clear_bit(wIndex, &ehci->resuming_ports);
                        ehci->reset_done[wIndex] = 0;
                        if (temp & PORT_PE)
                                set_bit(wIndex, &ehci->port_c_suspend);
                        usb_hcd_end_port_resume(&hcd->self, wIndex);
                }

                if (temp & PORT_OC)
                        status |= USB_PORT_STAT_OVERCURRENT;
                if (temp & PORT_RESET)
                        status |= USB_PORT_STAT_RESET;
                if (temp & PORT_POWER)
                        status |= USB_PORT_STAT_POWER;
                if (test_bit(wIndex, &ehci->port_c_suspend))
                        status |= USB_PORT_STAT_C_SUSPEND << 16;

#ifndef VERBOSE_DEBUG
        if (status & ~0xffff)   /* only if wPortChange is interesting */
#endif
                dbg_port (ehci, "GetStatus", wIndex + 1, temp);
                put_unaligned_le32(status, buf);
                break;
        case SetHubFeature:
                switch (wValue) {
                case C_HUB_LOCAL_POWER:
                case C_HUB_OVER_CURRENT:
                        /* no hub-wide feature/status flags */
                        break;

                default:
                        goto error;
                }
                break;
        case SetPortFeature:
                selector = wIndex >> 8;
                wIndex &= 0xff;
                if (unlikely(ehci->debug)) {
                        /* If the debug port is active any port
                         * feature requests should get denied */
                        if (wIndex == HCS_DEBUG_PORT(ehci->hcs_params) &&
                            (readl(&ehci->debug->control) & DBGP_ENABLED)) {
                                retval = -ENODEV;
                                goto error_exit;
                        }
                }
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                temp = ehci_readl(ehci, status_reg);
                if (temp & PORT_OWNER)
                        break;

                temp &= ~PORT_RWC_BITS;
                switch (wValue) {
                case USB_PORT_FEAT_SUSPEND:
                        if (ehci->no_selective_suspend)
                                break;
                        if ((temp & PORT_PE) == 0
                                        || (temp & PORT_RESET) != 0)
                                goto error;

                        /* After above check the port must be connected.
                         * Set appropriate bit thus could put phy into low power
                         * mode if we have hostpc feature
                         */
                        temp &= ~PORT_WKCONN_E;
                        temp |= PORT_WKDISC_E | PORT_WKOC_E;
                        ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
                        if (ehci->has_hostpc) {
                                spin_unlock_irqrestore(&ehci->lock, flags);
                                msleep(5);/* 5ms for HCD enter low pwr mode */
                                spin_lock_irqsave(&ehci->lock, flags);
                                temp1 = ehci_readl(ehci, hostpc_reg);
                                ehci_writel(ehci, temp1 | HOSTPC_PHCD,
                                        hostpc_reg);
                                temp1 = ehci_readl(ehci, hostpc_reg);
                                ehci_dbg(ehci, "Port%d phy low pwr mode %s\n",
                                        wIndex, (temp1 & HOSTPC_PHCD) ?
                                        "succeeded" : "failed");
                        }
                        set_bit(wIndex, &ehci->suspended_ports);
                        break;
                case USB_PORT_FEAT_POWER:
                        if (HCS_PPC (ehci->hcs_params))
                                ehci_writel(ehci, temp | PORT_POWER,
                                                status_reg);
                        break;
                case USB_PORT_FEAT_RESET:
                        if (temp & PORT_RESUME)
                                goto error;
                        /* line status bits may report this as low speed,
                         * which can be fine if this root hub has a
                         * transaction translator built in.
                         */
                        if ((temp & (PORT_PE|PORT_CONNECT)) == PORT_CONNECT
                                        && !ehci_is_TDI(ehci)
                                        && PORT_USB11 (temp)) {
                                ehci_dbg (ehci,
                                        "port %d low speed --> companion\n",
                                        wIndex + 1);
                                temp |= PORT_OWNER;
                        } else {
                                ehci_vdbg (ehci, "port %d reset\n", wIndex + 1);
                                temp |= PORT_RESET;
                                temp &= ~PORT_PE;

                                /*
                                 * caller must wait, then call GetPortStatus
                                 * usb 2.0 spec says 50 ms resets on root
                                 */
                                ehci->reset_done [wIndex] = jiffies
                                                + msecs_to_jiffies (50);
                        }
                        ehci_writel(ehci, temp, status_reg);
                        break;

                /* For downstream facing ports (these):  one hub port is put
                 * into test mode according to USB2 11.24.2.13, then the hub
                 * must be reset (which for root hub now means rmmod+modprobe,
                 * or else system reboot).  See EHCI 2.3.9 and 4.14 for info
                 * about the EHCI-specific stuff.
                 */
                case USB_PORT_FEAT_TEST:
                        if (!selector || selector > 5)
                                goto error;
                        spin_unlock_irqrestore(&ehci->lock, flags);
                        ehci_quiesce(ehci);
                        spin_lock_irqsave(&ehci->lock, flags);

                        /* Put all enabled ports into suspend */
                        while (ports--) {
                                u32 __iomem *sreg =
                                                &ehci->regs->port_status[ports];

                                temp = ehci_readl(ehci, sreg) & ~PORT_RWC_BITS;
                                if (temp & PORT_PE)
                                        ehci_writel(ehci, temp | PORT_SUSPEND,
                                                        sreg);
                        }

                        spin_unlock_irqrestore(&ehci->lock, flags);
                        ehci_halt(ehci);
                        spin_lock_irqsave(&ehci->lock, flags);

                        temp = ehci_readl(ehci, status_reg);
                        temp |= selector << 16;
                        ehci_writel(ehci, temp, status_reg);
                        break;

                default:
                        goto error;
                }
                ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */
                break;

        default:
error:
                /* "stall" on error */
                retval = -EPIPE;
        }
error_exit:
        spin_unlock_irqrestore (&ehci->lock, flags);
        return retval;
}

static void ehci_relinquish_port(struct usb_hcd *hcd, int portnum)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);

        if (ehci_is_TDI(ehci))
                return;
        set_owner(ehci, --portnum, PORT_OWNER);
}

static int ehci_port_handed_over(struct usb_hcd *hcd, int portnum)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
        u32 __iomem             *reg;

        if (ehci_is_TDI(ehci))
                return 0;
        reg = &ehci->regs->port_status[portnum - 1];
        return ehci_readl(ehci, reg) & PORT_OWNER;
}