/*
 * xHCI host controller driver
 *
 * Copyright (C) 2008 Intel Corp.
 *
 * Author: Sarah Sharp
 * Some code borrowed from the Linux EHCI driver.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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.
 */


#include <linux/slab.h>
#include <asm/unaligned.h>

#include "xhci.h"
#include "xhci-trace.h"

#define PORT_WAKE_BITS  (PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
#define PORT_RWC_BITS   (PORT_CSC | PORT_PEC | PORT_WRC | PORT_OCC | \
                         PORT_RC | PORT_PLC | PORT_PE)

/* USB 3 BOS descriptor and a capability descriptors, combined.
 * Fields will be adjusted and added later in xhci_create_usb3_bos_desc()
 */
static u8 usb_bos_descriptor [] = {
        USB_DT_BOS_SIZE,                /*  __u8 bLength, 5 bytes */
        USB_DT_BOS,                     /*  __u8 bDescriptorType */
        0x0F, 0x00,                     /*  __le16 wTotalLength, 15 bytes */
        0x1,                            /*  __u8 bNumDeviceCaps */
        /* First device capability, SuperSpeed */
        USB_DT_USB_SS_CAP_SIZE,         /*  __u8 bLength, 10 bytes */
        USB_DT_DEVICE_CAPABILITY,       /* Device Capability */
        USB_SS_CAP_TYPE,                /* bDevCapabilityType, SUPERSPEED_USB */
        0x00,                           /* bmAttributes, LTM off by default */
        USB_5GBPS_OPERATION, 0x00,      /* wSpeedsSupported, 5Gbps only */
        0x03,                           /* bFunctionalitySupport,
                                           USB 3.0 speed only */
        0x00,                           /* bU1DevExitLat, set later. */
        0x00, 0x00,                     /* __le16 bU2DevExitLat, set later. */
        /* Second device capability, SuperSpeedPlus */
        0x1c,                           /* bLength 28, will be adjusted later */
        USB_DT_DEVICE_CAPABILITY,       /* Device Capability */
        USB_SSP_CAP_TYPE,               /* bDevCapabilityType SUPERSPEED_PLUS */
        0x00,                           /* bReserved 0 */
        0x23, 0x00, 0x00, 0x00,         /* bmAttributes, SSAC=3 SSIC=1 */
        0x01, 0x00,                     /* wFunctionalitySupport */
        0x00, 0x00,                     /* wReserved 0 */
        /* Default Sublink Speed Attributes, overwrite if custom PSI exists */
        0x34, 0x00, 0x05, 0x00,         /* 5Gbps, symmetric, rx, ID = 4 */
        0xb4, 0x00, 0x05, 0x00,         /* 5Gbps, symmetric, tx, ID = 4 */
        0x35, 0x40, 0x0a, 0x00,         /* 10Gbps, SSP, symmetric, rx, ID = 5 */
        0xb5, 0x40, 0x0a, 0x00,         /* 10Gbps, SSP, symmetric, tx, ID = 5 */
};

static int xhci_create_usb3_bos_desc(struct xhci_hcd *xhci, char *buf,
                                     u16 wLength)
{
        int i, ssa_count;
        u32 temp;
        u16 desc_size, ssp_cap_size, ssa_size = 0;
        bool usb3_1 = false;

        desc_size = USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE;
        ssp_cap_size = sizeof(usb_bos_descriptor) - desc_size;

        /* does xhci support USB 3.1 Enhanced SuperSpeed */
        if (xhci->usb3_rhub.min_rev >= 0x01) {
                /* does xhci provide a PSI table for SSA speed attributes? */
                if (xhci->usb3_rhub.psi_count) {
                        /* two SSA entries for each unique PSI ID, RX and TX */
                        ssa_count = xhci->usb3_rhub.psi_uid_count * 2;
                        ssa_size = ssa_count * sizeof(u32);
                        ssp_cap_size -= 16; /* skip copying the default SSA */
                }
                desc_size += ssp_cap_size;
                usb3_1 = true;
        }
        memcpy(buf, &usb_bos_descriptor, min(desc_size, wLength));

        if (usb3_1) {
                /* modify bos descriptor bNumDeviceCaps and wTotalLength */
                buf[4] += 1;
                put_unaligned_le16(desc_size + ssa_size, &buf[2]);
        }

        if (wLength < USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE)
                return wLength;

        /* Indicate whether the host has LTM support. */
        temp = readl(&xhci->cap_regs->hcc_params);
        if (HCC_LTC(temp))
                buf[8] |= USB_LTM_SUPPORT;

        /* Set the U1 and U2 exit latencies. */
        if ((xhci->quirks & XHCI_LPM_SUPPORT)) {
                temp = readl(&xhci->cap_regs->hcs_params3);
                buf[12] = HCS_U1_LATENCY(temp);
                put_unaligned_le16(HCS_U2_LATENCY(temp), &buf[13]);
        }

        /* If PSI table exists, add the custom speed attributes from it */
        if (usb3_1 && xhci->usb3_rhub.psi_count) {
                u32 ssp_cap_base, bm_attrib, psi;
                int offset;

                ssp_cap_base = USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE;

                if (wLength < desc_size)
                        return wLength;
                buf[ssp_cap_base] = ssp_cap_size + ssa_size;

                /* attribute count SSAC bits 4:0 and ID count SSIC bits 8:5 */
                bm_attrib = (ssa_count - 1) & 0x1f;
                bm_attrib |= (xhci->usb3_rhub.psi_uid_count - 1) << 5;
                put_unaligned_le32(bm_attrib, &buf[ssp_cap_base + 4]);

                if (wLength < desc_size + ssa_size)
                        return wLength;
                /*
                 * Create the Sublink Speed Attributes (SSA) array.
                 * The xhci PSI field and USB 3.1 SSA fields are very similar,
                 * but link type bits 7:6 differ for values 01b and 10b.
                 * xhci has also only one PSI entry for a symmetric link when
                 * USB 3.1 requires two SSA entries (RX and TX) for every link
                 */
                offset = desc_size;
                for (i = 0; i < xhci->usb3_rhub.psi_count; i++) {
                        psi = xhci->usb3_rhub.psi[i];
                        psi &= ~USB_SSP_SUBLINK_SPEED_RSVD;
                        if ((psi & PLT_MASK) == PLT_SYM) {
                        /* Symmetric, create SSA RX and TX from one PSI entry */
                                put_unaligned_le32(psi, &buf[offset]);
                                psi |= 1 << 7;  /* turn entry to TX */
                                offset += 4;
                                if (offset >= desc_size + ssa_size)
                                        return desc_size + ssa_size;
                        } else if ((psi & PLT_MASK) == PLT_ASYM_RX) {
                                /* Asymetric RX, flip bits 7:6 for SSA */
                                psi ^= PLT_MASK;
                        }
                        put_unaligned_le32(psi, &buf[offset]);
                        offset += 4;
                        if (offset >= desc_size + ssa_size)
                                return desc_size + ssa_size;
                }
        }
        /* ssa_size is 0 for other than usb 3.1 hosts */
        return desc_size + ssa_size;
}

static void xhci_common_hub_descriptor(struct xhci_hcd *xhci,
                struct usb_hub_descriptor *desc, int ports)
{
        u16 temp;

        desc->bPwrOn2PwrGood = 10;      /* xhci section 5.4.9 says 20ms max */
        desc->bHubContrCurrent = 0;

        desc->bNbrPorts = ports;
        temp = 0;
        /* Bits 1:0 - support per-port power switching, or power always on */
        if (HCC_PPC(xhci->hcc_params))
                temp |= HUB_CHAR_INDV_PORT_LPSM;
        else
                temp |= HUB_CHAR_NO_LPSM;
        /* Bit  2 - root hubs are not part of a compound device */
        /* Bits 4:3 - individual port over current protection */
        temp |= HUB_CHAR_INDV_PORT_OCPM;
        /* Bits 6:5 - no TTs in root ports */
        /* Bit  7 - no port indicators */
        desc->wHubCharacteristics = cpu_to_le16(temp);
}

/* Fill in the USB 2.0 roothub descriptor */
static void xhci_usb2_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci,
                struct usb_hub_descriptor *desc)
{
        int ports;
        u16 temp;
        __u8 port_removable[(USB_MAXCHILDREN + 1 + 7) / 8];
        u32 portsc;
        unsigned int i;

        ports = xhci->num_usb2_ports;

        xhci_common_hub_descriptor(xhci, desc, ports);
        desc->bDescriptorType = USB_DT_HUB;
        temp = 1 + (ports / 8);
        desc->bDescLength = USB_DT_HUB_NONVAR_SIZE + 2 * temp;

        /* The Device Removable bits are reported on a byte granularity.
         * If the port doesn't exist within that byte, the bit is set to 0.
         */
        memset(port_removable, 0, sizeof(port_removable));
        for (i = 0; i < ports; i++) {
                portsc = readl(xhci->usb2_ports[i]);
                /* If a device is removable, PORTSC reports a 0, same as in the
                 * hub descriptor DeviceRemovable bits.
                 */
                if (portsc & PORT_DEV_REMOVE)
                        /* This math is hairy because bit 0 of DeviceRemovable
                         * is reserved, and bit 1 is for port 1, etc.
                         */
                        port_removable[(i + 1) / 8] |= 1 << ((i + 1) % 8);
        }

        /* ch11.h defines a hub descriptor that has room for USB_MAXCHILDREN
         * ports on it.  The USB 2.0 specification says that there are two
         * variable length fields at the end of the hub descriptor:
         * DeviceRemovable and PortPwrCtrlMask.  But since we can have less than
         * USB_MAXCHILDREN ports, we may need to use the DeviceRemovable array
         * to set PortPwrCtrlMask bits.  PortPwrCtrlMask must always be set to
         * 0xFF, so we initialize the both arrays (DeviceRemovable and
         * PortPwrCtrlMask) to 0xFF.  Then we set the DeviceRemovable for each
         * set of ports that actually exist.
         */
        memset(desc->u.hs.DeviceRemovable, 0xff,
                        sizeof(desc->u.hs.DeviceRemovable));
        memset(desc->u.hs.PortPwrCtrlMask, 0xff,
                        sizeof(desc->u.hs.PortPwrCtrlMask));

        for (i = 0; i < (ports + 1 + 7) / 8; i++)
                memset(&desc->u.hs.DeviceRemovable[i], port_removable[i],
                                sizeof(__u8));
}

/* Fill in the USB 3.0 roothub descriptor */
static void xhci_usb3_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci,
                struct usb_hub_descriptor *desc)
{
        int ports;
        u16 port_removable;
        u32 portsc;
        unsigned int i;

        ports = xhci->num_usb3_ports;
        xhci_common_hub_descriptor(xhci, desc, ports);
        desc->bDescriptorType = USB_DT_SS_HUB;
        desc->bDescLength = USB_DT_SS_HUB_SIZE;

        /* header decode latency should be zero for roothubs,
         * see section 4.23.5.2.
         */
        desc->u.ss.bHubHdrDecLat = 0;
        desc->u.ss.wHubDelay = 0;

        port_removable = 0;
        /* bit 0 is reserved, bit 1 is for port 1, etc. */
        for (i = 0; i < ports; i++) {
                portsc = readl(xhci->usb3_ports[i]);
                if (portsc & PORT_DEV_REMOVE)
                        port_removable |= 1 << (i + 1);
        }

        desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
}

static void xhci_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci,
                struct usb_hub_descriptor *desc)
{

        if (hcd->speed >= HCD_USB3)
                xhci_usb3_hub_descriptor(hcd, xhci, desc);
        else
                xhci_usb2_hub_descriptor(hcd, xhci, desc);

}

static unsigned int xhci_port_speed(unsigned int port_status)
{
        if (DEV_LOWSPEED(port_status))
                return USB_PORT_STAT_LOW_SPEED;
        if (DEV_HIGHSPEED(port_status))
                return USB_PORT_STAT_HIGH_SPEED;
        /*
         * FIXME: Yes, we should check for full speed, but the core uses that as
         * a default in portspeed() in usb/core/hub.c (which is the only place
         * USB_PORT_STAT_*_SPEED is used).
         */
        return 0;
}

/*
 * These bits are Read Only (RO) and should be saved and written to the
 * registers: 0, 3, 10:13, 30
 * connect status, over-current status, port speed, and device removable.
 * connect status and port speed are also sticky - meaning they're in
 * the AUX well and they aren't changed by a hot, warm, or cold reset.
 */
#define XHCI_PORT_RO    ((1<<0) | (1<<3) | (0xf<<10) | (1<<30))
/*
 * These bits are RW; writing a 0 clears the bit, writing a 1 sets the bit:
 * bits 5:8, 9, 14:15, 25:27
 * link state, port power, port indicator state, "wake on" enable state
 */
#define XHCI_PORT_RWS   ((0xf<<5) | (1<<9) | (0x3<<14) | (0x7<<25))
/*
 * These bits are RW; writing a 1 sets the bit, writing a 0 has no effect:
 * bit 4 (port reset)
 */
#define XHCI_PORT_RW1S  ((1<<4))
/*
 * These bits are RW; writing a 1 clears the bit, writing a 0 has no effect:
 * bits 1, 17, 18, 19, 20, 21, 22, 23
 * port enable/disable, and
 * change bits: connect, PED, warm port reset changed (reserved zero for USB 2.0 ports),
 * over-current, reset, link state, and L1 change
 */
#define XHCI_PORT_RW1CS ((1<<1) | (0x7f<<17))
/*
 * Bit 16 is RW, and writing a '1' to it causes the link state control to be
 * latched in
 */
#define XHCI_PORT_RW    ((1<<16))
/*
 * These bits are Reserved Zero (RsvdZ) and zero should be written to them:
 * bits 2, 24, 28:31
 */
#define XHCI_PORT_RZ    ((1<<2) | (1<<24) | (0xf<<28))

/*
 * Given a port state, this function returns a value that would result in the
 * port being in the same state, if the value was written to the port status
 * control register.
 * Save Read Only (RO) bits and save read/write bits where
 * writing a 0 clears the bit and writing a 1 sets the bit (RWS).
 * For all other types (RW1S, RW1CS, RW, and RZ), writing a '0' has no effect.
 */
u32 xhci_port_state_to_neutral(u32 state)
{
        /* Save read-only status and port state */
        return (state & XHCI_PORT_RO) | (state & XHCI_PORT_RWS);
}

/*
 * find slot id based on port number.
 * @port: The one-based port number from one of the two split roothubs.
 */
int xhci_find_slot_id_by_port(struct usb_hcd *hcd, struct xhci_hcd *xhci,
                u16 port)
{
        int slot_id;
        int i;
        enum usb_device_speed speed;

        slot_id = 0;
        for (i = 0; i < MAX_HC_SLOTS; i++) {
                if (!xhci->devs[i])
                        continue;
                speed = xhci->devs[i]->udev->speed;
                if (((speed >= USB_SPEED_SUPER) == (hcd->speed >= HCD_USB3))
                                && xhci->devs[i]->fake_port == port) {
                        slot_id = i;
                        break;
                }
        }

        return slot_id;
}

/*
 * Stop device
 * It issues stop endpoint command for EP 0 to 30. And wait the last command
 * to complete.
 * suspend will set to 1, if suspend bit need to set in command.
 */
static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
{
        struct xhci_virt_device *virt_dev;
        struct xhci_command *cmd;
        unsigned long flags;
        int ret;
        int i;

        ret = 0;
        virt_dev = xhci->devs[slot_id];
        if (!virt_dev)
                return -ENODEV;

        cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO);
        if (!cmd) {
                xhci_dbg(xhci, "Couldn't allocate command structure.\n");
                return -ENOMEM;
        }

        spin_lock_irqsave(&xhci->lock, flags);
        for (i = LAST_EP_INDEX; i > 0; i--) {
                if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue) {
                        struct xhci_command *command;
                        command = xhci_alloc_command(xhci, false, false,
                                                     GFP_NOWAIT);
                        if (!command) {
                                spin_unlock_irqrestore(&xhci->lock, flags);
                                xhci_free_command(xhci, cmd);
                                return -ENOMEM;

                        }
                        xhci_queue_stop_endpoint(xhci, command, slot_id, i,
                                                 suspend);
                }
        }
        xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend);
        xhci_ring_cmd_db(xhci);
        spin_unlock_irqrestore(&xhci->lock, flags);

        /* Wait for last stop endpoint command to finish */
        wait_for_completion(cmd->completion);

        if (cmd->status == COMP_CMD_ABORT || cmd->status == COMP_CMD_STOP) {
                xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n");
                ret = -ETIME;
        }
        xhci_free_command(xhci, cmd);
        return ret;
}

/*
 * Ring device, it rings the all doorbells unconditionally.
 */
void xhci_ring_device(struct xhci_hcd *xhci, int slot_id)
{
        int i, s;
        struct xhci_virt_ep *ep;

        for (i = 0; i < LAST_EP_INDEX + 1; i++) {
                ep = &xhci->devs[slot_id]->eps[i];

                if (ep->ep_state & EP_HAS_STREAMS) {
                        for (s = 1; s < ep->stream_info->num_streams; s++)
                                xhci_ring_ep_doorbell(xhci, slot_id, i, s);
                } else if (ep->ring && ep->ring->dequeue) {
                        xhci_ring_ep_doorbell(xhci, slot_id, i, 0);
                }
        }

        return;
}

static void xhci_disable_port(struct usb_hcd *hcd, struct xhci_hcd *xhci,
                u16 wIndex, __le32 __iomem *addr, u32 port_status)
{
        /* Don't allow the USB core to disable SuperSpeed ports. */
        if (hcd->speed >= HCD_USB3) {
                xhci_dbg(xhci, "Ignoring request to disable "
                                "SuperSpeed port.\n");
                return;
        }

        /* Write 1 to disable the port */
        writel(port_status | PORT_PE, addr);
        port_status = readl(addr);
        xhci_dbg(xhci, "disable port, actual port %d status  = 0x%x\n",
                        wIndex, port_status);
}

static void xhci_clear_port_change_bit(struct xhci_hcd *xhci, u16 wValue,
                u16 wIndex, __le32 __iomem *addr, u32 port_status)
{
        char *port_change_bit;
        u32 status;

        switch (wValue) {
        case USB_PORT_FEAT_C_RESET:
                status = PORT_RC;
                port_change_bit = "reset";
                break;
        case USB_PORT_FEAT_C_BH_PORT_RESET:
                status = PORT_WRC;
                port_change_bit = "warm(BH) reset";
                break;
        case USB_PORT_FEAT_C_CONNECTION:
                status = PORT_CSC;
                port_change_bit = "connect";
                break;
        case USB_PORT_FEAT_C_OVER_CURRENT:
                status = PORT_OCC;
                port_change_bit = "over-current";
                break;
        case USB_PORT_FEAT_C_ENABLE:
                status = PORT_PEC;
                port_change_bit = "enable/disable";
                break;
        case USB_PORT_FEAT_C_SUSPEND:
                status = PORT_PLC;
                port_change_bit = "suspend/resume";
                break;
        case USB_PORT_FEAT_C_PORT_LINK_STATE:
                status = PORT_PLC;
                port_change_bit = "link state";
                break;
        case USB_PORT_FEAT_C_PORT_CONFIG_ERROR:
                status = PORT_CEC;
                port_change_bit = "config error";
                break;
        default:
                /* Should never happen */
                return;
        }
        /* Change bits are all write 1 to clear */
        writel(port_status | status, addr);
        port_status = readl(addr);
        xhci_dbg(xhci, "clear port %s change, actual port %d status  = 0x%x\n",
                        port_change_bit, wIndex, port_status);
}

static int xhci_get_ports(struct usb_hcd *hcd, __le32 __iomem ***port_array)
{
        int max_ports;
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);

        if (hcd->speed >= HCD_USB3) {
                max_ports = xhci->num_usb3_ports;
                *port_array = xhci->usb3_ports;
        } else {
                max_ports = xhci->num_usb2_ports;
                *port_array = xhci->usb2_ports;
        }

        return max_ports;
}

void xhci_set_link_state(struct xhci_hcd *xhci, __le32 __iomem **port_array,
                                int port_id, u32 link_state)
{
        u32 temp;

        temp = readl(port_array[port_id]);
        temp = xhci_port_state_to_neutral(temp);
        temp &= ~PORT_PLS_MASK;
        temp |= PORT_LINK_STROBE | link_state;
        writel(temp, port_array[port_id]);
}

static void xhci_set_remote_wake_mask(struct xhci_hcd *xhci,
                __le32 __iomem **port_array, int port_id, u16 wake_mask)
{
        u32 temp;

        temp = readl(port_array[port_id]);
        temp = xhci_port_state_to_neutral(temp);

        if (wake_mask & USB_PORT_FEAT_REMOTE_WAKE_CONNECT)
                temp |= PORT_WKCONN_E;
        else
                temp &= ~PORT_WKCONN_E;

        if (wake_mask & USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT)
                temp |= PORT_WKDISC_E;
        else
                temp &= ~PORT_WKDISC_E;

        if (wake_mask & USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT)
                temp |= PORT_WKOC_E;
        else
                temp &= ~PORT_WKOC_E;

        writel(temp, port_array[port_id]);
}

/* Test and clear port RWC bit */
void xhci_test_and_clear_bit(struct xhci_hcd *xhci, __le32 __iomem **port_array,
                                int port_id, u32 port_bit)
{
        u32 temp;

        temp = readl(port_array[port_id]);
        if (temp & port_bit) {
                temp = xhci_port_state_to_neutral(temp);
                temp |= port_bit;
                writel(temp, port_array[port_id]);
        }
}

/* Updates Link Status for USB 2.1 port */
static void xhci_hub_report_usb2_link_state(u32 *status, u32 status_reg)
{
        if ((status_reg & PORT_PLS_MASK) == XDEV_U2)
                *status |= USB_PORT_STAT_L1;
}

/* Updates Link Status for super Speed port */
static void xhci_hub_report_usb3_link_state(struct xhci_hcd *xhci,
                u32 *status, u32 status_reg)
{
        u32 pls = status_reg & PORT_PLS_MASK;

        /* resume state is a xHCI internal state.
         * Do not report it to usb core, instead, pretend to be U3,
         * thus usb core knows it's not ready for transfer
         */
        if (pls == XDEV_RESUME) {
                *status |= USB_SS_PORT_LS_U3;
                return;
        }

        /* When the CAS bit is set then warm reset
         * should be performed on port
         */
        if (status_reg & PORT_CAS) {
                /* The CAS bit can be set while the port is
                 * in any link state.
                 * Only roothubs have CAS bit, so we
                 * pretend to be in compliance mode
                 * unless we're already in compliance
                 * or the inactive state.
                 */
                if (pls != USB_SS_PORT_LS_COMP_MOD &&
                    pls != USB_SS_PORT_LS_SS_INACTIVE) {
                        pls = USB_SS_PORT_LS_COMP_MOD;
                }
                /* Return also connection bit -
                 * hub state machine resets port
                 * when this bit is set.
                 */
                pls |= USB_PORT_STAT_CONNECTION;
        } else {
                /*
                 * If CAS bit isn't set but the Port is already at
                 * Compliance Mode, fake a connection so the USB core
                 * notices the Compliance state and resets the port.
                 * This resolves an issue generated by the SN65LVPE502CP
                 * in which sometimes the port enters compliance mode
                 * caused by a delay on the host-device negotiation.
                 */
                if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
                                (pls == USB_SS_PORT_LS_COMP_MOD))
                        pls |= USB_PORT_STAT_CONNECTION;
        }

        /* update status field */
        *status |= pls;
}

/*
 * Function for Compliance Mode Quirk.
 *
 * This Function verifies if all xhc USB3 ports have entered U0, if so,
 * the compliance mode timer is deleted. A port won't enter
 * compliance mode if it has previously entered U0.
 */
static void xhci_del_comp_mod_timer(struct xhci_hcd *xhci, u32 status,
                                    u16 wIndex)
{
        u32 all_ports_seen_u0 = ((1 << xhci->num_usb3_ports)-1);
        bool port_in_u0 = ((status & PORT_PLS_MASK) == XDEV_U0);

        if (!(xhci->quirks & XHCI_COMP_MODE_QUIRK))
                return;

        if ((xhci->port_status_u0 != all_ports_seen_u0) && port_in_u0) {
                xhci->port_status_u0 |= 1 << wIndex;
                if (xhci->port_status_u0 == all_ports_seen_u0) {
                        del_timer_sync(&xhci->comp_mode_recovery_timer);
                        xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
                                "All USB3 ports have entered U0 already!");
                        xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
                                "Compliance Mode Recovery Timer Deleted.");
                }
        }
}

static u32 xhci_get_ext_port_status(u32 raw_port_status, u32 port_li)
{
        u32 ext_stat = 0;
        int speed_id;

        /* only support rx and tx lane counts of 1 in usb3.1 spec */
        speed_id = DEV_PORT_SPEED(raw_port_status);
        ext_stat |= speed_id;           /* bits 3:0, RX speed id */
        ext_stat |= speed_id << 4;      /* bits 7:4, TX speed id */

        ext_stat |= PORT_RX_LANES(port_li) << 8;  /* bits 11:8 Rx lane count */
        ext_stat |= PORT_TX_LANES(port_li) << 12; /* bits 15:12 Tx lane count */

        return ext_stat;
}

/*
 * Converts a raw xHCI port status into the format that external USB 2.0 or USB
 * 3.0 hubs use.
 *
 * Possible side effects:
 *  - Mark a port as being done with device resume,
 *    and ring the endpoint doorbells.
 *  - Stop the Synopsys redriver Compliance Mode polling.
 *  - Drop and reacquire the xHCI lock, in order to wait for port resume.
 */
static u32 xhci_get_port_status(struct usb_hcd *hcd,
                struct xhci_bus_state *bus_state,
                __le32 __iomem **port_array,
                u16 wIndex, u32 raw_port_status,
                unsigned long flags)
        __releases(&xhci->lock)
        __acquires(&xhci->lock)
{
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        u32 status = 0;
        int slot_id;

        /* wPortChange bits */
        if (raw_port_status & PORT_CSC)
                status |= USB_PORT_STAT_C_CONNECTION << 16;
        if (raw_port_status & PORT_PEC)
                status |= USB_PORT_STAT_C_ENABLE << 16;
        if ((raw_port_status & PORT_OCC))
                status |= USB_PORT_STAT_C_OVERCURRENT << 16;
        if ((raw_port_status & PORT_RC))
                status |= USB_PORT_STAT_C_RESET << 16;
        /* USB3.0 only */
        if (hcd->speed >= HCD_USB3) {
                /* Port link change with port in resume state should not be
                 * reported to usbcore, as this is an internal state to be
                 * handled by xhci driver. Reporting PLC to usbcore may
                 * cause usbcore clearing PLC first and port change event
                 * irq won't be generated.
                 */
                if ((raw_port_status & PORT_PLC) &&
                        (raw_port_status & PORT_PLS_MASK) != XDEV_RESUME)
                        status |= USB_PORT_STAT_C_LINK_STATE << 16;
                if ((raw_port_status & PORT_WRC))
                        status |= USB_PORT_STAT_C_BH_RESET << 16;
                if ((raw_port_status & PORT_CEC))
                        status |= USB_PORT_STAT_C_CONFIG_ERROR << 16;
        }

        if (hcd->speed < HCD_USB3) {
                if ((raw_port_status & PORT_PLS_MASK) == XDEV_U3
                                && (raw_port_status & PORT_POWER))
                        status |= USB_PORT_STAT_SUSPEND;
        }
        if ((raw_port_status & PORT_PLS_MASK) == XDEV_RESUME &&
                !DEV_SUPERSPEED_ANY(raw_port_status)) {
                if ((raw_port_status & PORT_RESET) ||
                                !(raw_port_status & PORT_PE))
                        return 0xffffffff;
                /* did port event handler already start resume timing? */
                if (!bus_state->resume_done[wIndex]) {
                        /* If not, maybe we are in a host initated resume? */
                        if (test_bit(wIndex, &bus_state->resuming_ports)) {
                                /* Host initated resume doesn't time the resume
                                 * signalling using resume_done[].
                                 * It manually sets RESUME state, sleeps 20ms
                                 * and sets U0 state. This should probably be
                                 * changed, but not right now.
                                 */
                        } else {
                                /* port resume was discovered now and here,
                                 * start resume timing
                                 */
                                unsigned long timeout = jiffies +
                                        msecs_to_jiffies(USB_RESUME_TIMEOUT);

                                set_bit(wIndex, &bus_state->resuming_ports);
                                bus_state->resume_done[wIndex] = timeout;
                                mod_timer(&hcd->rh_timer, timeout);
                        }
                /* Has resume been signalled for USB_RESUME_TIME yet? */
                } else if (time_after_eq(jiffies,
                                         bus_state->resume_done[wIndex])) {
                        int time_left;

                        xhci_dbg(xhci, "Resume USB2 port %d\n",
                                        wIndex + 1);
                        bus_state->resume_done[wIndex] = 0;
                        clear_bit(wIndex, &bus_state->resuming_ports);

                        set_bit(wIndex, &bus_state->rexit_ports);
                        xhci_set_link_state(xhci, port_array, wIndex,
                                        XDEV_U0);

                        spin_unlock_irqrestore(&xhci->lock, flags);
                        time_left = wait_for_completion_timeout(
                                        &bus_state->rexit_done[wIndex],
                                        msecs_to_jiffies(
                                                XHCI_MAX_REXIT_TIMEOUT));
                        spin_lock_irqsave(&xhci->lock, flags);

                        if (time_left) {
                                slot_id = xhci_find_slot_id_by_port(hcd,
                                                xhci, wIndex + 1);
                                if (!slot_id) {
                                        xhci_dbg(xhci, "slot_id is zero\n");
                                        return 0xffffffff;
                                }
                                xhci_ring_device(xhci, slot_id);
                        } else {
                                int port_status = readl(port_array[wIndex]);
                                xhci_warn(xhci, "Port resume took longer than %i msec, port status = 0x%x\n",
                                                XHCI_MAX_REXIT_TIMEOUT,
                                                port_status);
                                status |= USB_PORT_STAT_SUSPEND;
                                clear_bit(wIndex, &bus_state->rexit_ports);
                        }

                        bus_state->port_c_suspend |= 1 << wIndex;
                        bus_state->suspended_ports &= ~(1 << wIndex);
                } else {
                        /*
                         * The resume has been signaling for less than
                         * USB_RESUME_TIME. Report the port status as SUSPEND,
                         * let the usbcore check port status again and clear
                         * resume signaling later.
                         */
                        status |= USB_PORT_STAT_SUSPEND;
                }
        }
        /*
         * Clear stale usb2 resume signalling variables in case port changed
         * state during resume signalling. For example on error
         */
        if ((bus_state->resume_done[wIndex] ||
             test_bit(wIndex, &bus_state->resuming_ports)) &&
            (raw_port_status & PORT_PLS_MASK) != XDEV_U3 &&
            (raw_port_status & PORT_PLS_MASK) != XDEV_RESUME) {
                bus_state->resume_done[wIndex] = 0;
                clear_bit(wIndex, &bus_state->resuming_ports);
        }


        if ((raw_port_status & PORT_PLS_MASK) == XDEV_U0 &&
            (raw_port_status & PORT_POWER)) {
                if (bus_state->suspended_ports & (1 << wIndex)) {
                        bus_state->suspended_ports &= ~(1 << wIndex);
                        if (hcd->speed < HCD_USB3)
                                bus_state->port_c_suspend |= 1 << wIndex;
                }
                bus_state->resume_done[wIndex] = 0;
                clear_bit(wIndex, &bus_state->resuming_ports);
        }
        if (raw_port_status & PORT_CONNECT) {
                status |= USB_PORT_STAT_CONNECTION;
                status |= xhci_port_speed(raw_port_status);
        }
        if (raw_port_status & PORT_PE)
                status |= USB_PORT_STAT_ENABLE;
        if (raw_port_status & PORT_OC)
                status |= USB_PORT_STAT_OVERCURRENT;
        if (raw_port_status & PORT_RESET)
                status |= USB_PORT_STAT_RESET;
        if (raw_port_status & PORT_POWER) {
                if (hcd->speed >= HCD_USB3)
                        status |= USB_SS_PORT_STAT_POWER;
                else
                        status |= USB_PORT_STAT_POWER;
        }
        /* Update Port Link State */
        if (hcd->speed >= HCD_USB3) {
                xhci_hub_report_usb3_link_state(xhci, &status, raw_port_status);
                /*
                 * Verify if all USB3 Ports Have entered U0 already.
                 * Delete Compliance Mode Timer if so.
                 */
                xhci_del_comp_mod_timer(xhci, raw_port_status, wIndex);
        } else {
                xhci_hub_report_usb2_link_state(&status, raw_port_status);
        }
        if (bus_state->port_c_suspend & (1 << wIndex))
                status |= USB_PORT_STAT_C_SUSPEND << 16;

        return status;
}

int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
                u16 wIndex, char *buf, u16 wLength)
{
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        int max_ports;
        unsigned long flags;
        u32 temp, status;
        int retval = 0;
        __le32 __iomem **port_array;
        int slot_id;
        struct xhci_bus_state *bus_state;
        u16 link_state = 0;
        u16 wake_mask = 0;
        u16 timeout = 0;

        max_ports = xhci_get_ports(hcd, &port_array);
        bus_state = &xhci->bus_state[hcd_index(hcd)];

        spin_lock_irqsave(&xhci->lock, flags);
        switch (typeReq) {
        case GetHubStatus:
                /* No power source, over-current reported per port */
                memset(buf, 0, 4);
                break;
        case GetHubDescriptor:
                /* Check to make sure userspace is asking for the USB 3.0 hub
                 * descriptor for the USB 3.0 roothub.  If not, we stall the
                 * endpoint, like external hubs do.
                 */
                if (hcd->speed >= HCD_USB3 &&
                                (wLength < USB_DT_SS_HUB_SIZE ||
                                 wValue != (USB_DT_SS_HUB << 8))) {
                        xhci_dbg(xhci, "Wrong hub descriptor type for "
                                        "USB 3.0 roothub.\n");
                        goto error;
                }
                xhci_hub_descriptor(hcd, xhci,
                                (struct usb_hub_descriptor *) buf);
                break;
        case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
                if ((wValue & 0xff00) != (USB_DT_BOS << 8))
                        goto error;

                if (hcd->speed < HCD_USB3)
                        goto error;

                retval = xhci_create_usb3_bos_desc(xhci, buf, wLength);
                spin_unlock_irqrestore(&xhci->lock, flags);
                return retval;
        case GetPortStatus:
                if (!wIndex || wIndex > max_ports)
                        goto error;
                wIndex--;
                temp = readl(port_array[wIndex]);
                if (temp == 0xffffffff) {
                        retval = -ENODEV;
                        break;
                }
                status = xhci_get_port_status(hcd, bus_state, port_array,
                                wIndex, temp, flags);
                if (status == 0xffffffff)
                        goto error;

                xhci_dbg(xhci, "get port status, actual port %d status  = 0x%x\n",
                                wIndex, temp);
                xhci_dbg(xhci, "Get port status returned 0x%x\n", status);

                put_unaligned(cpu_to_le32(status), (__le32 *) buf);
                /* if USB 3.1 extended port status return additional 4 bytes */
                if (wValue == 0x02) {
                        u32 port_li;

                        if (hcd->speed < HCD_USB31 || wLength != 8) {
                                xhci_err(xhci, "get ext port status invalid parameter\n");
                                retval = -EINVAL;
                                break;
                        }
                        port_li = readl(port_array[wIndex] + PORTLI);
                        status = xhci_get_ext_port_status(temp, port_li);
                        put_unaligned_le32(cpu_to_le32(status), &buf[4]);
                }
                break;
        case SetPortFeature:
                if (wValue == USB_PORT_FEAT_LINK_STATE)
                        link_state = (wIndex & 0xff00) >> 3;
                if (wValue == USB_PORT_FEAT_REMOTE_WAKE_MASK)
                        wake_mask = wIndex & 0xff00;
                /* The MSB of wIndex is the U1/U2 timeout */
                timeout = (wIndex & 0xff00) >> 8;
                wIndex &= 0xff;
                if (!wIndex || wIndex > max_ports)
                        goto error;
                wIndex--;
                temp = readl(port_array[wIndex]);
                if (temp == 0xffffffff) {
                        retval = -ENODEV;
                        break;
                }
                temp = xhci_port_state_to_neutral(temp);
                /* FIXME: What new port features do we need to support? */
                switch (wValue) {
                case USB_PORT_FEAT_SUSPEND:
                        temp = readl(port_array[wIndex]);
                        if ((temp & PORT_PLS_MASK) != XDEV_U0) {
                                /* Resume the port to U0 first */
                                xhci_set_link_state(xhci, port_array, wIndex,
                                                        XDEV_U0);
                                spin_unlock_irqrestore(&xhci->lock, flags);
                                msleep(10);
                                spin_lock_irqsave(&xhci->lock, flags);
                        }
                        /* In spec software should not attempt to suspend
                         * a port unless the port reports that it is in the
                         * enabled (PED = ‘1’,PLS < ‘3’) state.
                         */
                        temp = readl(port_array[wIndex]);
                        if ((temp & PORT_PE) == 0 || (temp & PORT_RESET)
                                || (temp & PORT_PLS_MASK) >= XDEV_U3) {
                                xhci_warn(xhci, "USB core suspending device "
                                          "not in U0/U1/U2.\n");
                                goto error;
                        }

                        slot_id = xhci_find_slot_id_by_port(hcd, xhci,
                                        wIndex + 1);
                        if (!slot_id) {

                                xhci_warn(xhci, "slot_id is zero\n");
                                goto error;
                        }
                        /* unlock to execute stop endpoint commands */
                        spin_unlock_irqrestore(&xhci->lock, flags);
                        xhci_stop_device(xhci, slot_id, 1);
                        spin_lock_irqsave(&xhci->lock, flags);

                        xhci_set_link_state(xhci, port_array, wIndex, XDEV_U3);

                        spin_unlock_irqrestore(&xhci->lock, flags);
                        msleep(10); /* wait device to enter */
                        spin_lock_irqsave(&xhci->lock, flags);

                        temp = readl(port_array[wIndex]);
                        bus_state->suspended_ports |= 1 << wIndex;
                        break;
                case USB_PORT_FEAT_LINK_STATE:
                        temp = readl(port_array[wIndex]);

                        /* Disable port */
                        if (link_state == USB_SS_PORT_LS_SS_DISABLED) {
                                xhci_dbg(xhci, "Disable port %d\n", wIndex);
                                temp = xhci_port_state_to_neutral(temp);
                                /*
                                 * Clear all change bits, so that we get a new
                                 * connection event.
                                 */
                                temp |= PORT_CSC | PORT_PEC | PORT_WRC |
                                        PORT_OCC | PORT_RC | PORT_PLC |
                                        PORT_CEC;
                                writel(temp | PORT_PE, port_array[wIndex]);
                                temp = readl(port_array[wIndex]);
                                break;
                        }

                        /* Put link in RxDetect (enable port) */
                        if (link_state == USB_SS_PORT_LS_RX_DETECT) {
                                xhci_dbg(xhci, "Enable port %d\n", wIndex);
                                xhci_set_link_state(xhci, port_array, wIndex,
                                                link_state);
                                temp = readl(port_array[wIndex]);
                                break;
                        }

                        /* Software should not attempt to set
                         * port link state above '3' (U3) and the port
                         * must be enabled.
                         */
                        if ((temp & PORT_PE) == 0 ||
                                (link_state > USB_SS_PORT_LS_U3)) {
                                xhci_warn(xhci, "Cannot set link state.\n");
                                goto error;
                        }

                        if (link_state == USB_SS_PORT_LS_U3) {
                                slot_id = xhci_find_slot_id_by_port(hcd, xhci,
                                                wIndex + 1);
                                if (slot_id) {
                                        /* unlock to execute stop endpoint
                                         * commands */
                                        spin_unlock_irqrestore(&xhci->lock,
                                                                flags);
                                        xhci_stop_device(xhci, slot_id, 1);
                                        spin_lock_irqsave(&xhci->lock, flags);
                                }
                        }

                        xhci_set_link_state(xhci, port_array, wIndex,
                                                link_state);

                        spin_unlock_irqrestore(&xhci->lock, flags);
                        msleep(20); /* wait device to enter */
                        spin_lock_irqsave(&xhci->lock, flags);

                        temp = readl(port_array[wIndex]);
                        if (link_state == USB_SS_PORT_LS_U3)
                                bus_state->suspended_ports |= 1 << wIndex;
                        break;
                case USB_PORT_FEAT_POWER:
                        /*
                         * Turn on ports, even if there isn't per-port switching.
                         * HC will report connect events even before this is set.
                         * However, hub_wq will ignore the roothub events until
                         * the roothub is registered.
                         */
                        writel(temp | PORT_POWER, port_array[wIndex]);

                        temp = readl(port_array[wIndex]);
                        xhci_dbg(xhci, "set port power, actual port %d status  = 0x%x\n", wIndex, temp);

                        spin_unlock_irqrestore(&xhci->lock, flags);
                        temp = usb_acpi_power_manageable(hcd->self.root_hub,
                                        wIndex);
                        if (temp)
                                usb_acpi_set_power_state(hcd->self.root_hub,
                                                wIndex, true);
                        spin_lock_irqsave(&xhci->lock, flags);
                        break;
                case USB_PORT_FEAT_RESET:
                        temp = (temp | PORT_RESET);
                        writel(temp, port_array[wIndex]);

                        temp = readl(port_array[wIndex]);
                        xhci_dbg(xhci, "set port reset, actual port %d status  = 0x%x\n", wIndex, temp);
                        break;
                case USB_PORT_FEAT_REMOTE_WAKE_MASK:
                        xhci_set_remote_wake_mask(xhci, port_array,
                                        wIndex, wake_mask);
                        temp = readl(port_array[wIndex]);
                        xhci_dbg(xhci, "set port remote wake mask, "
                                        "actual port %d status  = 0x%x\n",
                                        wIndex, temp);
                        break;
                case USB_PORT_FEAT_BH_PORT_RESET:
                        temp |= PORT_WR;
                        writel(temp, port_array[wIndex]);

                        temp = readl(port_array[wIndex]);
                        break;
                case USB_PORT_FEAT_U1_TIMEOUT:
                        if (hcd->speed < HCD_USB3)
                                goto error;
                        temp = readl(port_array[wIndex] + PORTPMSC);
                        temp &= ~PORT_U1_TIMEOUT_MASK;
                        temp |= PORT_U1_TIMEOUT(timeout);
                        writel(temp, port_array[wIndex] + PORTPMSC);
                        break;
                case USB_PORT_FEAT_U2_TIMEOUT:
                        if (hcd->speed < HCD_USB3)
                                goto error;
                        temp = readl(port_array[wIndex] + PORTPMSC);
                        temp &= ~PORT_U2_TIMEOUT_MASK;
                        temp |= PORT_U2_TIMEOUT(timeout);
                        writel(temp, port_array[wIndex] + PORTPMSC);
                        break;
                default:
                        goto error;
                }
                /* unblock any posted writes */
                temp = readl(port_array[wIndex]);
                break;
        case ClearPortFeature:
                if (!wIndex || wIndex > max_ports)
                        goto error;
                wIndex--;
                temp = readl(port_array[wIndex]);
                if (temp == 0xffffffff) {
                        retval = -ENODEV;
                        break;
                }
                /* FIXME: What new port features do we need to support? */
                temp = xhci_port_state_to_neutral(temp);
                switch (wValue) {
                case USB_PORT_FEAT_SUSPEND:
                        temp = readl(port_array[wIndex]);
                        xhci_dbg(xhci, "clear USB_PORT_FEAT_SUSPEND\n");
                        xhci_dbg(xhci, "PORTSC %04x\n", temp);
                        if (temp & PORT_RESET)
                                goto error;
                        if ((temp & PORT_PLS_MASK) == XDEV_U3) {
                                if ((temp & PORT_PE) == 0)
                                        goto error;

                                set_bit(wIndex, &bus_state->resuming_ports);
                                xhci_set_link_state(xhci, port_array, wIndex,
                                                        XDEV_RESUME);
                                spin_unlock_irqrestore(&xhci->lock, flags);
                                msleep(USB_RESUME_TIMEOUT);
                                spin_lock_irqsave(&xhci->lock, flags);
                                xhci_set_link_state(xhci, port_array, wIndex,
                                                        XDEV_U0);
                                clear_bit(wIndex, &bus_state->resuming_ports);
                        }
                        bus_state->port_c_suspend |= 1 << wIndex;

                        slot_id = xhci_find_slot_id_by_port(hcd, xhci,
                                        wIndex + 1);
                        if (!slot_id) {
                                xhci_dbg(xhci, "slot_id is zero\n");
                                goto error;
                        }
                        xhci_ring_device(xhci, slot_id);
                        break;
                case USB_PORT_FEAT_C_SUSPEND:
                        bus_state->port_c_suspend &= ~(1 << wIndex);
                case USB_PORT_FEAT_C_RESET:
                case USB_PORT_FEAT_C_BH_PORT_RESET:
                case USB_PORT_FEAT_C_CONNECTION:
                case USB_PORT_FEAT_C_OVER_CURRENT:
                case USB_PORT_FEAT_C_ENABLE:
                case USB_PORT_FEAT_C_PORT_LINK_STATE:
                case USB_PORT_FEAT_C_PORT_CONFIG_ERROR:
                        xhci_clear_port_change_bit(xhci, wValue, wIndex,
                                        port_array[wIndex], temp);
                        break;
                case USB_PORT_FEAT_ENABLE:
                        xhci_disable_port(hcd, xhci, wIndex,
                                        port_array[wIndex], temp);
                        break;
                case USB_PORT_FEAT_POWER:
                        writel(temp & ~PORT_POWER, port_array[wIndex]);

                        spin_unlock_irqrestore(&xhci->lock, flags);
                        temp = usb_acpi_power_manageable(hcd->self.root_hub,
                                        wIndex);
                        if (temp)
                                usb_acpi_set_power_state(hcd->self.root_hub,
                                                wIndex, false);
                        spin_lock_irqsave(&xhci->lock, flags);
                        break;
                default:
                        goto error;
                }
                break;
        default:
error:
                /* "stall" on error */
                retval = -EPIPE;
        }
        spin_unlock_irqrestore(&xhci->lock, flags);
        return retval;
}

/*
 * Returns 0 if the status hasn't changed, or the number of bytes in buf.
 * Ports are 0-indexed from the HCD point of view,
 * and 1-indexed from the USB core pointer of view.
 *
 * Note that the status change bits will be cleared as soon as a port status
 * change event is generated, so we use the saved status from that event.
 */
int xhci_hub_status_data(struct usb_hcd *hcd, char *buf)
{
        unsigned long flags;
        u32 temp, status;
        u32 mask;
        int i, retval;
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        int max_ports;
        __le32 __iomem **port_array;
        struct xhci_bus_state *bus_state;
        bool reset_change = false;

        max_ports = xhci_get_ports(hcd, &port_array);
        bus_state = &xhci->bus_state[hcd_index(hcd)];

        /* Initial status is no changes */
        retval = (max_ports + 8) / 8;
        memset(buf, 0, retval);

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

        mask = PORT_CSC | PORT_PEC | PORT_OCC | PORT_PLC | PORT_WRC | PORT_CEC;

        spin_lock_irqsave(&xhci->lock, flags);
        /* For each port, did anything change?  If so, set that bit in buf. */
        for (i = 0; i < max_ports; i++) {
                temp = readl(port_array[i]);
                if (temp == 0xffffffff) {
                        retval = -ENODEV;
                        break;
                }
                if ((temp & mask) != 0 ||
                        (bus_state->port_c_suspend & 1 << i) ||
                        (bus_state->resume_done[i] && time_after_eq(
                            jiffies, bus_state->resume_done[i]))) {
                        buf[(i + 1) / 8] |= 1 << (i + 1) % 8;
                        status = 1;
                }
                if ((temp & PORT_RC))
                        reset_change = true;
        }
        if (!status && !reset_change) {
                xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
                clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
        }
        spin_unlock_irqrestore(&xhci->lock, flags);
        return status ? retval : 0;
}

#ifdef CONFIG_PM

int xhci_bus_suspend(struct usb_hcd *hcd)
{
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        int max_ports, port_index;
        __le32 __iomem **port_array;
        struct xhci_bus_state *bus_state;
        unsigned long flags;

        max_ports = xhci_get_ports(hcd, &port_array);
        bus_state = &xhci->bus_state[hcd_index(hcd)];

        spin_lock_irqsave(&xhci->lock, flags);

        if (hcd->self.root_hub->do_remote_wakeup) {
                if (bus_state->resuming_ports ||        /* USB2 */
                    bus_state->port_remote_wakeup) {    /* USB3 */
                        spin_unlock_irqrestore(&xhci->lock, flags);
                        xhci_dbg(xhci, "suspend failed because a port is resuming\n");
                        return -EBUSY;
                }
        }

        port_index = max_ports;
        bus_state->bus_suspended = 0;
        while (port_index--) {
                /* suspend the port if the port is not suspended */
                u32 t1, t2;
                int slot_id;

                t1 = readl(port_array[port_index]);
                t2 = xhci_port_state_to_neutral(t1);

                if ((t1 & PORT_PE) && !(t1 & PORT_PLS_MASK)) {
                        xhci_dbg(xhci, "port %d not suspended\n", port_index);
                        slot_id = xhci_find_slot_id_by_port(hcd, xhci,
                                        port_index + 1);
                        if (slot_id) {
                                spin_unlock_irqrestore(&xhci->lock, flags);
                                xhci_stop_device(xhci, slot_id, 1);
                                spin_lock_irqsave(&xhci->lock, flags);
                        }
                        t2 &= ~PORT_PLS_MASK;
                        t2 |= PORT_LINK_STROBE | XDEV_U3;
                        set_bit(port_index, &bus_state->bus_suspended);
                }
                /* USB core sets remote wake mask for USB 3.0 hubs,
                 * including the USB 3.0 roothub, but only if CONFIG_PM
                 * is enabled, so also enable remote wake here.
                 */
                if (hcd->self.root_hub->do_remote_wakeup) {
                        if (t1 & PORT_CONNECT) {
                                t2 |= PORT_WKOC_E | PORT_WKDISC_E;
                                t2 &= ~PORT_WKCONN_E;
                        } else {
                                t2 |= PORT_WKOC_E | PORT_WKCONN_E;
                                t2 &= ~PORT_WKDISC_E;
                        }
                } else
                        t2 &= ~PORT_WAKE_BITS;

                t1 = xhci_port_state_to_neutral(t1);
                if (t1 != t2)
                        writel(t2, port_array[port_index]);
        }
        hcd->state = HC_STATE_SUSPENDED;
        bus_state->next_statechange = jiffies + msecs_to_jiffies(10);
        spin_unlock_irqrestore(&xhci->lock, flags);
        return 0;
}

/*
 * Workaround for missing Cold Attach Status (CAS) if device re-plugged in S3.
 * warm reset a USB3 device stuck in polling or compliance mode after resume.
 * See Intel 100/c230 series PCH specification update Doc #332692-006 Errata #8
 */
static bool xhci_port_missing_cas_quirk(int port_index,
                                             __le32 __iomem **port_array)
{
        u32 portsc;

        portsc = readl(port_array[port_index]);

        /* if any of these are set we are not stuck */
        if (portsc & (PORT_CONNECT | PORT_CAS))
                return false;

        if (((portsc & PORT_PLS_MASK) != XDEV_POLLING) &&
            ((portsc & PORT_PLS_MASK) != XDEV_COMP_MODE))
                return false;

        /* clear wakeup/change bits, and do a warm port reset */
        portsc &= ~(PORT_RWC_BITS | PORT_CEC | PORT_WAKE_BITS);
        portsc |= PORT_WR;
        writel(portsc, port_array[port_index]);
        /* flush write */
        readl(port_array[port_index]);
        return true;
}

int xhci_bus_resume(struct usb_hcd *hcd)
{
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        int max_ports, port_index;
        __le32 __iomem **port_array;
        struct xhci_bus_state *bus_state;
        u32 temp;
        unsigned long flags;
        unsigned long port_was_suspended = 0;
        bool need_usb2_u3_exit = false;
        int slot_id;
        int sret;

        max_ports = xhci_get_ports(hcd, &port_array);
        bus_state = &xhci->bus_state[hcd_index(hcd)];

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

        spin_lock_irqsave(&xhci->lock, flags);
        if (!HCD_HW_ACCESSIBLE(hcd)) {
                spin_unlock_irqrestore(&xhci->lock, flags);
                return -ESHUTDOWN;
        }

        /* delay the irqs */
        temp = readl(&xhci->op_regs->command);
        temp &= ~CMD_EIE;
        writel(temp, &xhci->op_regs->command);

        port_index = max_ports;
        while (port_index--) {
                /* Check whether need resume ports. If needed
                   resume port and disable remote wakeup */
                u32 temp;

                temp = readl(port_array[port_index]);

                /* warm reset CAS limited ports stuck in polling/compliance */
                if ((xhci->quirks & XHCI_MISSING_CAS) &&
                    (hcd->speed >= HCD_USB3) &&
                    xhci_port_missing_cas_quirk(port_index, port_array)) {
                        xhci_dbg(xhci, "reset stuck port %d\n", port_index);
                        continue;
                }
                if (DEV_SUPERSPEED_ANY(temp))
                        temp &= ~(PORT_RWC_BITS | PORT_CEC | PORT_WAKE_BITS);
                else
                        temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
                if (test_bit(port_index, &bus_state->bus_suspended) &&
                    (temp & PORT_PLS_MASK)) {
                        set_bit(port_index, &port_was_suspended);
                        if (!DEV_SUPERSPEED_ANY(temp)) {
                                xhci_set_link_state(xhci, port_array,
                                                port_index, XDEV_RESUME);
                                need_usb2_u3_exit = true;
                        }
                } else
                        writel(temp, port_array[port_index]);
        }

        if (need_usb2_u3_exit) {
                spin_unlock_irqrestore(&xhci->lock, flags);
                msleep(USB_RESUME_TIMEOUT);
                spin_lock_irqsave(&xhci->lock, flags);
        }

        port_index = max_ports;
        while (port_index--) {
                if (!(port_was_suspended & BIT(port_index)))
                        continue;
                /* Clear PLC to poll it later after XDEV_U0 */
                xhci_test_and_clear_bit(xhci, port_array, port_index, PORT_PLC);
                xhci_set_link_state(xhci, port_array, port_index, XDEV_U0);
        }

        port_index = max_ports;
        while (port_index--) {
                if (!(port_was_suspended & BIT(port_index)))
                        continue;
                /* Poll and Clear PLC */
                sret = xhci_handshake(port_array[port_index], PORT_PLC,
                                      PORT_PLC, 10 * 1000);
                if (sret)
                        xhci_warn(xhci, "port %d resume PLC timeout\n",
                                  port_index);
                xhci_test_and_clear_bit(xhci, port_array, port_index, PORT_PLC);
                slot_id = xhci_find_slot_id_by_port(hcd, xhci, port_index + 1);
                if (slot_id)
                        xhci_ring_device(xhci, slot_id);
        }

        (void) readl(&xhci->op_regs->command);

        bus_state->next_statechange = jiffies + msecs_to_jiffies(5);
        /* re-enable irqs */
        temp = readl(&xhci->op_regs->command);
        temp |= CMD_EIE;
        writel(temp, &xhci->op_regs->command);
        temp = readl(&xhci->op_regs->command);

        spin_unlock_irqrestore(&xhci->lock, flags);
        return 0;
}

#endif  /* CONFIG_PM */