x86/mm/pat: Don't report PAT on CPUs that don't support it

[linux/fpc-iii.git] / drivers / phy / phy-rockchip-inno-usb2.c

/*
 * Rockchip USB2.0 PHY with Innosilicon IP block driver
 *
 * Copyright (C) 2016 Fuzhou Rockchip Electronics Co., Ltd
 *
 * 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.
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/extcon.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/gpio/consumer.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>

#define BIT_WRITEABLE_SHIFT     16
#define SCHEDULE_DELAY          (60 * HZ)
#define OTG_SCHEDULE_DELAY      (2 * HZ)

enum rockchip_usb2phy_port_id {
        USB2PHY_PORT_OTG,
        USB2PHY_PORT_HOST,
        USB2PHY_NUM_PORTS,
};

enum rockchip_usb2phy_host_state {
        PHY_STATE_HS_ONLINE     = 0,
        PHY_STATE_DISCONNECT    = 1,
        PHY_STATE_CONNECT       = 2,
        PHY_STATE_FS_LS_ONLINE  = 4,
};

/**
 * Different states involved in USB charger detection.
 * USB_CHG_STATE_UNDEFINED      USB charger is not connected or detection
 *                              process is not yet started.
 * USB_CHG_STATE_WAIT_FOR_DCD   Waiting for Data pins contact.
 * USB_CHG_STATE_DCD_DONE       Data pin contact is detected.
 * USB_CHG_STATE_PRIMARY_DONE   Primary detection is completed (Detects
 *                              between SDP and DCP/CDP).
 * USB_CHG_STATE_SECONDARY_DONE Secondary detection is completed (Detects
 *                              between DCP and CDP).
 * USB_CHG_STATE_DETECTED       USB charger type is determined.
 */
enum usb_chg_state {
        USB_CHG_STATE_UNDEFINED = 0,
        USB_CHG_STATE_WAIT_FOR_DCD,
        USB_CHG_STATE_DCD_DONE,
        USB_CHG_STATE_PRIMARY_DONE,
        USB_CHG_STATE_SECONDARY_DONE,
        USB_CHG_STATE_DETECTED,
};

static const unsigned int rockchip_usb2phy_extcon_cable[] = {
        EXTCON_USB,
        EXTCON_USB_HOST,
        EXTCON_CHG_USB_SDP,
        EXTCON_CHG_USB_CDP,
        EXTCON_CHG_USB_DCP,
        EXTCON_CHG_USB_SLOW,
        EXTCON_NONE,
};

struct usb2phy_reg {
        unsigned int    offset;
        unsigned int    bitend;
        unsigned int    bitstart;
        unsigned int    disable;
        unsigned int    enable;
};

/**
 * struct rockchip_chg_det_reg: usb charger detect registers
 * @cp_det: charging port detected successfully.
 * @dcp_det: dedicated charging port detected successfully.
 * @dp_det: assert data pin connect successfully.
 * @idm_sink_en: open dm sink curren.
 * @idp_sink_en: open dp sink current.
 * @idp_src_en: open dm source current.
 * @rdm_pdwn_en: open dm pull down resistor.
 * @vdm_src_en: open dm voltage source.
 * @vdp_src_en: open dp voltage source.
 * @opmode: utmi operational mode.
 */
struct rockchip_chg_det_reg {
        struct usb2phy_reg      cp_det;
        struct usb2phy_reg      dcp_det;
        struct usb2phy_reg      dp_det;
        struct usb2phy_reg      idm_sink_en;
        struct usb2phy_reg      idp_sink_en;
        struct usb2phy_reg      idp_src_en;
        struct usb2phy_reg      rdm_pdwn_en;
        struct usb2phy_reg      vdm_src_en;
        struct usb2phy_reg      vdp_src_en;
        struct usb2phy_reg      opmode;
};

/**
 * struct rockchip_usb2phy_port_cfg: usb-phy port configuration.
 * @phy_sus: phy suspend register.
 * @bvalid_det_en: vbus valid rise detection enable register.
 * @bvalid_det_st: vbus valid rise detection status register.
 * @bvalid_det_clr: vbus valid rise detection clear register.
 * @ls_det_en: linestate detection enable register.
 * @ls_det_st: linestate detection state register.
 * @ls_det_clr: linestate detection clear register.
 * @utmi_avalid: utmi vbus avalid status register.
 * @utmi_bvalid: utmi vbus bvalid status register.
 * @utmi_ls: utmi linestate state register.
 * @utmi_hstdet: utmi host disconnect register.
 */
struct rockchip_usb2phy_port_cfg {
        struct usb2phy_reg      phy_sus;
        struct usb2phy_reg      bvalid_det_en;
        struct usb2phy_reg      bvalid_det_st;
        struct usb2phy_reg      bvalid_det_clr;
        struct usb2phy_reg      ls_det_en;
        struct usb2phy_reg      ls_det_st;
        struct usb2phy_reg      ls_det_clr;
        struct usb2phy_reg      utmi_avalid;
        struct usb2phy_reg      utmi_bvalid;
        struct usb2phy_reg      utmi_ls;
        struct usb2phy_reg      utmi_hstdet;
};

/**
 * struct rockchip_usb2phy_cfg: usb-phy configuration.
 * @reg: the address offset of grf for usb-phy config.
 * @num_ports: specify how many ports that the phy has.
 * @clkout_ctl: keep on/turn off output clk of phy.
 * @chg_det: charger detection registers.
 */
struct rockchip_usb2phy_cfg {
        unsigned int    reg;
        unsigned int    num_ports;
        struct usb2phy_reg      clkout_ctl;
        const struct rockchip_usb2phy_port_cfg  port_cfgs[USB2PHY_NUM_PORTS];
        const struct rockchip_chg_det_reg       chg_det;
};

/**
 * struct rockchip_usb2phy_port: usb-phy port data.
 * @port_id: flag for otg port or host port.
 * @suspended: phy suspended flag.
 * @utmi_avalid: utmi avalid status usage flag.
 *      true    - use avalid to get vbus status
 *      flase   - use bvalid to get vbus status
 * @vbus_attached: otg device vbus status.
 * @bvalid_irq: IRQ number assigned for vbus valid rise detection.
 * @ls_irq: IRQ number assigned for linestate detection.
 * @mutex: for register updating in sm_work.
 * @chg_work: charge detect work.
 * @otg_sm_work: OTG state machine work.
 * @sm_work: HOST state machine work.
 * @phy_cfg: port register configuration, assigned by driver data.
 * @event_nb: hold event notification callback.
 * @state: define OTG enumeration states before device reset.
 * @mode: the dr_mode of the controller.
 */
struct rockchip_usb2phy_port {
        struct phy      *phy;
        unsigned int    port_id;
        bool            suspended;
        bool            utmi_avalid;
        bool            vbus_attached;
        int             bvalid_irq;
        int             ls_irq;
        struct mutex    mutex;
        struct          delayed_work chg_work;
        struct          delayed_work otg_sm_work;
        struct          delayed_work sm_work;
        const struct    rockchip_usb2phy_port_cfg *port_cfg;
        struct notifier_block   event_nb;
        enum usb_otg_state      state;
        enum usb_dr_mode        mode;
};

/**
 * struct rockchip_usb2phy: usb2.0 phy driver data.
 * @grf: General Register Files regmap.
 * @clk: clock struct of phy input clk.
 * @clk480m: clock struct of phy output clk.
 * @clk_hw: clock struct of phy output clk management.
 * @chg_state: states involved in USB charger detection.
 * @chg_type: USB charger types.
 * @dcd_retries: The retry count used to track Data contact
 *               detection process.
 * @edev: extcon device for notification registration
 * @phy_cfg: phy register configuration, assigned by driver data.
 * @ports: phy port instance.
 */
struct rockchip_usb2phy {
        struct device   *dev;
        struct regmap   *grf;
        struct clk      *clk;
        struct clk      *clk480m;
        struct clk_hw   clk480m_hw;
        enum usb_chg_state      chg_state;
        enum power_supply_type  chg_type;
        u8                      dcd_retries;
        struct extcon_dev       *edev;
        const struct rockchip_usb2phy_cfg       *phy_cfg;
        struct rockchip_usb2phy_port    ports[USB2PHY_NUM_PORTS];
};

static inline int property_enable(struct rockchip_usb2phy *rphy,
                                  const struct usb2phy_reg *reg, bool en)
{
        unsigned int val, mask, tmp;

        tmp = en ? reg->enable : reg->disable;
        mask = GENMASK(reg->bitend, reg->bitstart);
        val = (tmp << reg->bitstart) | (mask << BIT_WRITEABLE_SHIFT);

        return regmap_write(rphy->grf, reg->offset, val);
}

static inline bool property_enabled(struct rockchip_usb2phy *rphy,
                                    const struct usb2phy_reg *reg)
{
        int ret;
        unsigned int tmp, orig;
        unsigned int mask = GENMASK(reg->bitend, reg->bitstart);

        ret = regmap_read(rphy->grf, reg->offset, &orig);
        if (ret)
                return false;

        tmp = (orig & mask) >> reg->bitstart;
        return tmp == reg->enable;
}

static int rockchip_usb2phy_clk480m_prepare(struct clk_hw *hw)
{
        struct rockchip_usb2phy *rphy =
                container_of(hw, struct rockchip_usb2phy, clk480m_hw);
        int ret;

        /* turn on 480m clk output if it is off */
        if (!property_enabled(rphy, &rphy->phy_cfg->clkout_ctl)) {
                ret = property_enable(rphy, &rphy->phy_cfg->clkout_ctl, true);
                if (ret)
                        return ret;

                /* waiting for the clk become stable */
                usleep_range(1200, 1300);
        }

        return 0;
}

static void rockchip_usb2phy_clk480m_unprepare(struct clk_hw *hw)
{
        struct rockchip_usb2phy *rphy =
                container_of(hw, struct rockchip_usb2phy, clk480m_hw);

        /* turn off 480m clk output */
        property_enable(rphy, &rphy->phy_cfg->clkout_ctl, false);
}

static int rockchip_usb2phy_clk480m_prepared(struct clk_hw *hw)
{
        struct rockchip_usb2phy *rphy =
                container_of(hw, struct rockchip_usb2phy, clk480m_hw);

        return property_enabled(rphy, &rphy->phy_cfg->clkout_ctl);
}

static unsigned long
rockchip_usb2phy_clk480m_recalc_rate(struct clk_hw *hw,
                                     unsigned long parent_rate)
{
        return 480000000;
}

static const struct clk_ops rockchip_usb2phy_clkout_ops = {
        .prepare = rockchip_usb2phy_clk480m_prepare,
        .unprepare = rockchip_usb2phy_clk480m_unprepare,
        .is_prepared = rockchip_usb2phy_clk480m_prepared,
        .recalc_rate = rockchip_usb2phy_clk480m_recalc_rate,
};

static void rockchip_usb2phy_clk480m_unregister(void *data)
{
        struct rockchip_usb2phy *rphy = data;

        of_clk_del_provider(rphy->dev->of_node);
        clk_unregister(rphy->clk480m);
}

static int
rockchip_usb2phy_clk480m_register(struct rockchip_usb2phy *rphy)
{
        struct device_node *node = rphy->dev->of_node;
        struct clk_init_data init;
        const char *clk_name;
        int ret;

        init.flags = 0;
        init.name = "clk_usbphy_480m";
        init.ops = &rockchip_usb2phy_clkout_ops;

        /* optional override of the clockname */
        of_property_read_string(node, "clock-output-names", &init.name);

        if (rphy->clk) {
                clk_name = __clk_get_name(rphy->clk);
                init.parent_names = &clk_name;
                init.num_parents = 1;
        } else {
                init.parent_names = NULL;
                init.num_parents = 0;
        }

        rphy->clk480m_hw.init = &init;

        /* register the clock */
        rphy->clk480m = clk_register(rphy->dev, &rphy->clk480m_hw);
        if (IS_ERR(rphy->clk480m)) {
                ret = PTR_ERR(rphy->clk480m);
                goto err_ret;
        }

        ret = of_clk_add_provider(node, of_clk_src_simple_get, rphy->clk480m);
        if (ret < 0)
                goto err_clk_provider;

        ret = devm_add_action(rphy->dev, rockchip_usb2phy_clk480m_unregister,
                              rphy);
        if (ret < 0)
                goto err_unreg_action;

        return 0;

err_unreg_action:
        of_clk_del_provider(node);
err_clk_provider:
        clk_unregister(rphy->clk480m);
err_ret:
        return ret;
}

static int rockchip_usb2phy_extcon_register(struct rockchip_usb2phy *rphy)
{
        int ret;
        struct device_node *node = rphy->dev->of_node;
        struct extcon_dev *edev;

        if (of_property_read_bool(node, "extcon")) {
                edev = extcon_get_edev_by_phandle(rphy->dev, 0);
                if (IS_ERR(edev)) {
                        if (PTR_ERR(edev) != -EPROBE_DEFER)
                                dev_err(rphy->dev, "Invalid or missing extcon\n");
                        return PTR_ERR(edev);
                }
        } else {
                /* Initialize extcon device */
                edev = devm_extcon_dev_allocate(rphy->dev,
                                                rockchip_usb2phy_extcon_cable);

                if (IS_ERR(edev))
                        return -ENOMEM;

                ret = devm_extcon_dev_register(rphy->dev, edev);
                if (ret) {
                        dev_err(rphy->dev, "failed to register extcon device\n");
                        return ret;
                }
        }

        rphy->edev = edev;

        return 0;
}

static int rockchip_usb2phy_init(struct phy *phy)
{
        struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.parent);
        int ret = 0;

        mutex_lock(&rport->mutex);

        if (rport->port_id == USB2PHY_PORT_OTG) {
                if (rport->mode != USB_DR_MODE_HOST) {
                        /* clear bvalid status and enable bvalid detect irq */
                        ret = property_enable(rphy,
                                              &rport->port_cfg->bvalid_det_clr,
                                              true);
                        if (ret)
                                goto out;

                        ret = property_enable(rphy,
                                              &rport->port_cfg->bvalid_det_en,
                                              true);
                        if (ret)
                                goto out;

                        schedule_delayed_work(&rport->otg_sm_work,
                                              OTG_SCHEDULE_DELAY);
                } else {
                        /* If OTG works in host only mode, do nothing. */
                        dev_dbg(&rport->phy->dev, "mode %d\n", rport->mode);
                }
        } else if (rport->port_id == USB2PHY_PORT_HOST) {
                /* clear linestate and enable linestate detect irq */
                ret = property_enable(rphy, &rport->port_cfg->ls_det_clr, true);
                if (ret)
                        goto out;

                ret = property_enable(rphy, &rport->port_cfg->ls_det_en, true);
                if (ret)
                        goto out;

                schedule_delayed_work(&rport->sm_work, SCHEDULE_DELAY);
        }

out:
        mutex_unlock(&rport->mutex);
        return ret;
}

static int rockchip_usb2phy_power_on(struct phy *phy)
{
        struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.parent);
        int ret;

        dev_dbg(&rport->phy->dev, "port power on\n");

        if (!rport->suspended)
                return 0;

        ret = clk_prepare_enable(rphy->clk480m);
        if (ret)
                return ret;

        ret = property_enable(rphy, &rport->port_cfg->phy_sus, false);
        if (ret)
                return ret;

        rport->suspended = false;
        return 0;
}

static int rockchip_usb2phy_power_off(struct phy *phy)
{
        struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.parent);
        int ret;

        dev_dbg(&rport->phy->dev, "port power off\n");

        if (rport->suspended)
                return 0;

        ret = property_enable(rphy, &rport->port_cfg->phy_sus, true);
        if (ret)
                return ret;

        rport->suspended = true;
        clk_disable_unprepare(rphy->clk480m);

        return 0;
}

static int rockchip_usb2phy_exit(struct phy *phy)
{
        struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);

        if (rport->port_id == USB2PHY_PORT_OTG &&
            rport->mode != USB_DR_MODE_HOST) {
                cancel_delayed_work_sync(&rport->otg_sm_work);
                cancel_delayed_work_sync(&rport->chg_work);
        } else if (rport->port_id == USB2PHY_PORT_HOST)
                cancel_delayed_work_sync(&rport->sm_work);

        return 0;
}

static const struct phy_ops rockchip_usb2phy_ops = {
        .init           = rockchip_usb2phy_init,
        .exit           = rockchip_usb2phy_exit,
        .power_on       = rockchip_usb2phy_power_on,
        .power_off      = rockchip_usb2phy_power_off,
        .owner          = THIS_MODULE,
};

static void rockchip_usb2phy_otg_sm_work(struct work_struct *work)
{
        struct rockchip_usb2phy_port *rport =
                container_of(work, struct rockchip_usb2phy_port,
                             otg_sm_work.work);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(rport->phy->dev.parent);
        static unsigned int cable;
        unsigned long delay;
        bool vbus_attach, sch_work, notify_charger;

        if (rport->utmi_avalid)
                vbus_attach =
                        property_enabled(rphy, &rport->port_cfg->utmi_avalid);
        else
                vbus_attach =
                        property_enabled(rphy, &rport->port_cfg->utmi_bvalid);

        sch_work = false;
        notify_charger = false;
        delay = OTG_SCHEDULE_DELAY;
        dev_dbg(&rport->phy->dev, "%s otg sm work\n",
                usb_otg_state_string(rport->state));

        switch (rport->state) {
        case OTG_STATE_UNDEFINED:
                rport->state = OTG_STATE_B_IDLE;
                if (!vbus_attach)
                        rockchip_usb2phy_power_off(rport->phy);
                /* fall through */
        case OTG_STATE_B_IDLE:
                if (extcon_get_cable_state_(rphy->edev, EXTCON_USB_HOST) > 0) {
                        dev_dbg(&rport->phy->dev, "usb otg host connect\n");
                        rport->state = OTG_STATE_A_HOST;
                        rockchip_usb2phy_power_on(rport->phy);
                        return;
                } else if (vbus_attach) {
                        dev_dbg(&rport->phy->dev, "vbus_attach\n");
                        switch (rphy->chg_state) {
                        case USB_CHG_STATE_UNDEFINED:
                                schedule_delayed_work(&rport->chg_work, 0);
                                return;
                        case USB_CHG_STATE_DETECTED:
                                switch (rphy->chg_type) {
                                case POWER_SUPPLY_TYPE_USB:
                                        dev_dbg(&rport->phy->dev,
                                                "sdp cable is connecetd\n");
                                        rockchip_usb2phy_power_on(rport->phy);
                                        rport->state = OTG_STATE_B_PERIPHERAL;
                                        notify_charger = true;
                                        sch_work = true;
                                        cable = EXTCON_CHG_USB_SDP;
                                        break;
                                case POWER_SUPPLY_TYPE_USB_DCP:
                                        dev_dbg(&rport->phy->dev,
                                                "dcp cable is connecetd\n");
                                        rockchip_usb2phy_power_off(rport->phy);
                                        notify_charger = true;
                                        sch_work = true;
                                        cable = EXTCON_CHG_USB_DCP;
                                        break;
                                case POWER_SUPPLY_TYPE_USB_CDP:
                                        dev_dbg(&rport->phy->dev,
                                                "cdp cable is connecetd\n");
                                        rockchip_usb2phy_power_on(rport->phy);
                                        rport->state = OTG_STATE_B_PERIPHERAL;
                                        notify_charger = true;
                                        sch_work = true;
                                        cable = EXTCON_CHG_USB_CDP;
                                        break;
                                default:
                                        break;
                                }
                                break;
                        default:
                                break;
                        }
                } else {
                        notify_charger = true;
                        rphy->chg_state = USB_CHG_STATE_UNDEFINED;
                        rphy->chg_type = POWER_SUPPLY_TYPE_UNKNOWN;
                }

                if (rport->vbus_attached != vbus_attach) {
                        rport->vbus_attached = vbus_attach;

                        if (notify_charger && rphy->edev) {
                                extcon_set_cable_state_(rphy->edev,
                                                        cable, vbus_attach);
                                if (cable == EXTCON_CHG_USB_SDP)
                                        extcon_set_state_sync(rphy->edev,
                                                              EXTCON_USB,
                                                              vbus_attach);
                        }
                }
                break;
        case OTG_STATE_B_PERIPHERAL:
                if (!vbus_attach) {
                        dev_dbg(&rport->phy->dev, "usb disconnect\n");
                        rphy->chg_state = USB_CHG_STATE_UNDEFINED;
                        rphy->chg_type = POWER_SUPPLY_TYPE_UNKNOWN;
                        rport->state = OTG_STATE_B_IDLE;
                        delay = 0;
                        rockchip_usb2phy_power_off(rport->phy);
                }
                sch_work = true;
                break;
        case OTG_STATE_A_HOST:
                if (extcon_get_cable_state_(rphy->edev, EXTCON_USB_HOST) == 0) {
                        dev_dbg(&rport->phy->dev, "usb otg host disconnect\n");
                        rport->state = OTG_STATE_B_IDLE;
                        rockchip_usb2phy_power_off(rport->phy);
                }
                break;
        default:
                break;
        }

        if (sch_work)
                schedule_delayed_work(&rport->otg_sm_work, delay);
}

static const char *chg_to_string(enum power_supply_type chg_type)
{
        switch (chg_type) {
        case POWER_SUPPLY_TYPE_USB:
                return "USB_SDP_CHARGER";
        case POWER_SUPPLY_TYPE_USB_DCP:
                return "USB_DCP_CHARGER";
        case POWER_SUPPLY_TYPE_USB_CDP:
                return "USB_CDP_CHARGER";
        default:
                return "INVALID_CHARGER";
        }
}

static void rockchip_chg_enable_dcd(struct rockchip_usb2phy *rphy,
                                    bool en)
{
        property_enable(rphy, &rphy->phy_cfg->chg_det.rdm_pdwn_en, en);
        property_enable(rphy, &rphy->phy_cfg->chg_det.idp_src_en, en);
}

static void rockchip_chg_enable_primary_det(struct rockchip_usb2phy *rphy,
                                            bool en)
{
        property_enable(rphy, &rphy->phy_cfg->chg_det.vdp_src_en, en);
        property_enable(rphy, &rphy->phy_cfg->chg_det.idm_sink_en, en);
}

static void rockchip_chg_enable_secondary_det(struct rockchip_usb2phy *rphy,
                                              bool en)
{
        property_enable(rphy, &rphy->phy_cfg->chg_det.vdm_src_en, en);
        property_enable(rphy, &rphy->phy_cfg->chg_det.idp_sink_en, en);
}

#define CHG_DCD_POLL_TIME       (100 * HZ / 1000)
#define CHG_DCD_MAX_RETRIES     6
#define CHG_PRIMARY_DET_TIME    (40 * HZ / 1000)
#define CHG_SECONDARY_DET_TIME  (40 * HZ / 1000)
static void rockchip_chg_detect_work(struct work_struct *work)
{
        struct rockchip_usb2phy_port *rport =
                container_of(work, struct rockchip_usb2phy_port, chg_work.work);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(rport->phy->dev.parent);
        bool is_dcd, tmout, vout;
        unsigned long delay;

        dev_dbg(&rport->phy->dev, "chg detection work state = %d\n",
                rphy->chg_state);
        switch (rphy->chg_state) {
        case USB_CHG_STATE_UNDEFINED:
                if (!rport->suspended)
                        rockchip_usb2phy_power_off(rport->phy);
                /* put the controller in non-driving mode */
                property_enable(rphy, &rphy->phy_cfg->chg_det.opmode, false);
                /* Start DCD processing stage 1 */
                rockchip_chg_enable_dcd(rphy, true);
                rphy->chg_state = USB_CHG_STATE_WAIT_FOR_DCD;
                rphy->dcd_retries = 0;
                delay = CHG_DCD_POLL_TIME;
                break;
        case USB_CHG_STATE_WAIT_FOR_DCD:
                /* get data contact detection status */
                is_dcd = property_enabled(rphy, &rphy->phy_cfg->chg_det.dp_det);
                tmout = ++rphy->dcd_retries == CHG_DCD_MAX_RETRIES;
                /* stage 2 */
                if (is_dcd || tmout) {
                        /* stage 4 */
                        /* Turn off DCD circuitry */
                        rockchip_chg_enable_dcd(rphy, false);
                        /* Voltage Source on DP, Probe on DM */
                        rockchip_chg_enable_primary_det(rphy, true);
                        delay = CHG_PRIMARY_DET_TIME;
                        rphy->chg_state = USB_CHG_STATE_DCD_DONE;
                } else {
                        /* stage 3 */
                        delay = CHG_DCD_POLL_TIME;
                }
                break;
        case USB_CHG_STATE_DCD_DONE:
                vout = property_enabled(rphy, &rphy->phy_cfg->chg_det.cp_det);
                rockchip_chg_enable_primary_det(rphy, false);
                if (vout) {
                        /* Voltage Source on DM, Probe on DP  */
                        rockchip_chg_enable_secondary_det(rphy, true);
                        delay = CHG_SECONDARY_DET_TIME;
                        rphy->chg_state = USB_CHG_STATE_PRIMARY_DONE;
                } else {
                        if (rphy->dcd_retries == CHG_DCD_MAX_RETRIES) {
                                /* floating charger found */
                                rphy->chg_type = POWER_SUPPLY_TYPE_USB_DCP;
                                rphy->chg_state = USB_CHG_STATE_DETECTED;
                                delay = 0;
                        } else {
                                rphy->chg_type = POWER_SUPPLY_TYPE_USB;
                                rphy->chg_state = USB_CHG_STATE_DETECTED;
                                delay = 0;
                        }
                }
                break;
        case USB_CHG_STATE_PRIMARY_DONE:
                vout = property_enabled(rphy, &rphy->phy_cfg->chg_det.dcp_det);
                /* Turn off voltage source */
                rockchip_chg_enable_secondary_det(rphy, false);
                if (vout)
                        rphy->chg_type = POWER_SUPPLY_TYPE_USB_DCP;
                else
                        rphy->chg_type = POWER_SUPPLY_TYPE_USB_CDP;
                /* fall through */
        case USB_CHG_STATE_SECONDARY_DONE:
                rphy->chg_state = USB_CHG_STATE_DETECTED;
                delay = 0;
                /* fall through */
        case USB_CHG_STATE_DETECTED:
                /* put the controller in normal mode */
                property_enable(rphy, &rphy->phy_cfg->chg_det.opmode, true);
                rockchip_usb2phy_otg_sm_work(&rport->otg_sm_work.work);
                dev_info(&rport->phy->dev, "charger = %s\n",
                         chg_to_string(rphy->chg_type));
                return;
        default:
                return;
        }

        schedule_delayed_work(&rport->chg_work, delay);
}

/*
 * The function manage host-phy port state and suspend/resume phy port
 * to save power.
 *
 * we rely on utmi_linestate and utmi_hostdisconnect to identify whether
 * devices is disconnect or not. Besides, we do not need care it is FS/LS
 * disconnected or HS disconnected, actually, we just only need get the
 * device is disconnected at last through rearm the delayed work,
 * to suspend the phy port in _PHY_STATE_DISCONNECT_ case.
 *
 * NOTE: It may invoke *phy_powr_off or *phy_power_on which will invoke
 * some clk related APIs, so do not invoke it from interrupt context directly.
 */
static void rockchip_usb2phy_sm_work(struct work_struct *work)
{
        struct rockchip_usb2phy_port *rport =
                container_of(work, struct rockchip_usb2phy_port, sm_work.work);
        struct rockchip_usb2phy *rphy = dev_get_drvdata(rport->phy->dev.parent);
        unsigned int sh = rport->port_cfg->utmi_hstdet.bitend -
                          rport->port_cfg->utmi_hstdet.bitstart + 1;
        unsigned int ul, uhd, state;
        unsigned int ul_mask, uhd_mask;
        int ret;

        mutex_lock(&rport->mutex);

        ret = regmap_read(rphy->grf, rport->port_cfg->utmi_ls.offset, &ul);
        if (ret < 0)
                goto next_schedule;

        ret = regmap_read(rphy->grf, rport->port_cfg->utmi_hstdet.offset,
                          &uhd);
        if (ret < 0)
                goto next_schedule;

        uhd_mask = GENMASK(rport->port_cfg->utmi_hstdet.bitend,
                           rport->port_cfg->utmi_hstdet.bitstart);
        ul_mask = GENMASK(rport->port_cfg->utmi_ls.bitend,
                          rport->port_cfg->utmi_ls.bitstart);

        /* stitch on utmi_ls and utmi_hstdet as phy state */
        state = ((uhd & uhd_mask) >> rport->port_cfg->utmi_hstdet.bitstart) |
                (((ul & ul_mask) >> rport->port_cfg->utmi_ls.bitstart) << sh);

        switch (state) {
        case PHY_STATE_HS_ONLINE:
                dev_dbg(&rport->phy->dev, "HS online\n");
                break;
        case PHY_STATE_FS_LS_ONLINE:
                /*
                 * For FS/LS device, the online state share with connect state
                 * from utmi_ls and utmi_hstdet register, so we distinguish
                 * them via suspended flag.
                 *
                 * Plus, there are two cases, one is D- Line pull-up, and D+
                 * line pull-down, the state is 4; another is D+ line pull-up,
                 * and D- line pull-down, the state is 2.
                 */
                if (!rport->suspended) {
                        /* D- line pull-up, D+ line pull-down */
                        dev_dbg(&rport->phy->dev, "FS/LS online\n");
                        break;
                }
                /* fall through */
        case PHY_STATE_CONNECT:
                if (rport->suspended) {
                        dev_dbg(&rport->phy->dev, "Connected\n");
                        rockchip_usb2phy_power_on(rport->phy);
                        rport->suspended = false;
                } else {
                        /* D+ line pull-up, D- line pull-down */
                        dev_dbg(&rport->phy->dev, "FS/LS online\n");
                }
                break;
        case PHY_STATE_DISCONNECT:
                if (!rport->suspended) {
                        dev_dbg(&rport->phy->dev, "Disconnected\n");
                        rockchip_usb2phy_power_off(rport->phy);
                        rport->suspended = true;
                }

                /*
                 * activate the linestate detection to get the next device
                 * plug-in irq.
                 */
                property_enable(rphy, &rport->port_cfg->ls_det_clr, true);
                property_enable(rphy, &rport->port_cfg->ls_det_en, true);

                /*
                 * we don't need to rearm the delayed work when the phy port
                 * is suspended.
                 */
                mutex_unlock(&rport->mutex);
                return;
        default:
                dev_dbg(&rport->phy->dev, "unknown phy state\n");
                break;
        }

next_schedule:
        mutex_unlock(&rport->mutex);
        schedule_delayed_work(&rport->sm_work, SCHEDULE_DELAY);
}

static irqreturn_t rockchip_usb2phy_linestate_irq(int irq, void *data)
{
        struct rockchip_usb2phy_port *rport = data;
        struct rockchip_usb2phy *rphy = dev_get_drvdata(rport->phy->dev.parent);

        if (!property_enabled(rphy, &rport->port_cfg->ls_det_st))
                return IRQ_NONE;

        mutex_lock(&rport->mutex);

        /* disable linestate detect irq and clear its status */
        property_enable(rphy, &rport->port_cfg->ls_det_en, false);
        property_enable(rphy, &rport->port_cfg->ls_det_clr, true);

        mutex_unlock(&rport->mutex);

        /*
         * In this case for host phy port, a new device is plugged in,
         * meanwhile, if the phy port is suspended, we need rearm the work to
         * resume it and mange its states; otherwise, we do nothing about that.
         */
        if (rport->suspended && rport->port_id == USB2PHY_PORT_HOST)
                rockchip_usb2phy_sm_work(&rport->sm_work.work);

        return IRQ_HANDLED;
}

static irqreturn_t rockchip_usb2phy_bvalid_irq(int irq, void *data)
{
        struct rockchip_usb2phy_port *rport = data;
        struct rockchip_usb2phy *rphy = dev_get_drvdata(rport->phy->dev.parent);

        if (!property_enabled(rphy, &rport->port_cfg->bvalid_det_st))
                return IRQ_NONE;

        mutex_lock(&rport->mutex);

        /* clear bvalid detect irq pending status */
        property_enable(rphy, &rport->port_cfg->bvalid_det_clr, true);

        mutex_unlock(&rport->mutex);

        rockchip_usb2phy_otg_sm_work(&rport->otg_sm_work.work);

        return IRQ_HANDLED;
}

static int rockchip_usb2phy_host_port_init(struct rockchip_usb2phy *rphy,
                                           struct rockchip_usb2phy_port *rport,
                                           struct device_node *child_np)
{
        int ret;

        rport->port_id = USB2PHY_PORT_HOST;
        rport->port_cfg = &rphy->phy_cfg->port_cfgs[USB2PHY_PORT_HOST];
        rport->suspended = true;

        mutex_init(&rport->mutex);
        INIT_DELAYED_WORK(&rport->sm_work, rockchip_usb2phy_sm_work);

        rport->ls_irq = of_irq_get_byname(child_np, "linestate");
        if (rport->ls_irq < 0) {
                dev_err(rphy->dev, "no linestate irq provided\n");
                return rport->ls_irq;
        }

        ret = devm_request_threaded_irq(rphy->dev, rport->ls_irq, NULL,
                                        rockchip_usb2phy_linestate_irq,
                                        IRQF_ONESHOT,
                                        "rockchip_usb2phy", rport);
        if (ret) {
                dev_err(rphy->dev, "failed to request linestate irq handle\n");
                return ret;
        }

        return 0;
}

static int rockchip_otg_event(struct notifier_block *nb,
                              unsigned long event, void *ptr)
{
        struct rockchip_usb2phy_port *rport =
                container_of(nb, struct rockchip_usb2phy_port, event_nb);

        schedule_delayed_work(&rport->otg_sm_work, OTG_SCHEDULE_DELAY);

        return NOTIFY_DONE;
}

static int rockchip_usb2phy_otg_port_init(struct rockchip_usb2phy *rphy,
                                          struct rockchip_usb2phy_port *rport,
                                          struct device_node *child_np)
{
        int ret;

        rport->port_id = USB2PHY_PORT_OTG;
        rport->port_cfg = &rphy->phy_cfg->port_cfgs[USB2PHY_PORT_OTG];
        rport->state = OTG_STATE_UNDEFINED;

        /*
         * set suspended flag to true, but actually don't
         * put phy in suspend mode, it aims to enable usb
         * phy and clock in power_on() called by usb controller
         * driver during probe.
         */
        rport->suspended = true;
        rport->vbus_attached = false;

        mutex_init(&rport->mutex);

        rport->mode = of_usb_get_dr_mode_by_phy(child_np, -1);
        if (rport->mode == USB_DR_MODE_HOST) {
                ret = 0;
                goto out;
        }

        INIT_DELAYED_WORK(&rport->chg_work, rockchip_chg_detect_work);
        INIT_DELAYED_WORK(&rport->otg_sm_work, rockchip_usb2phy_otg_sm_work);

        rport->utmi_avalid =
                of_property_read_bool(child_np, "rockchip,utmi-avalid");

        rport->bvalid_irq = of_irq_get_byname(child_np, "otg-bvalid");
        if (rport->bvalid_irq < 0) {
                dev_err(rphy->dev, "no vbus valid irq provided\n");
                ret = rport->bvalid_irq;
                goto out;
        }

        ret = devm_request_threaded_irq(rphy->dev, rport->bvalid_irq, NULL,
                                        rockchip_usb2phy_bvalid_irq,
                                        IRQF_ONESHOT,
                                        "rockchip_usb2phy_bvalid", rport);
        if (ret) {
                dev_err(rphy->dev, "failed to request otg-bvalid irq handle\n");
                goto out;
        }

        if (!IS_ERR(rphy->edev)) {
                rport->event_nb.notifier_call = rockchip_otg_event;

                ret = extcon_register_notifier(rphy->edev, EXTCON_USB_HOST,
                                               &rport->event_nb);
                if (ret)
                        dev_err(rphy->dev, "register USB HOST notifier failed\n");
        }

out:
        return ret;
}

static int rockchip_usb2phy_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct device_node *np = dev->of_node;
        struct device_node *child_np;
        struct phy_provider *provider;
        struct rockchip_usb2phy *rphy;
        const struct rockchip_usb2phy_cfg *phy_cfgs;
        const struct of_device_id *match;
        unsigned int reg;
        int index, ret;

        rphy = devm_kzalloc(dev, sizeof(*rphy), GFP_KERNEL);
        if (!rphy)
                return -ENOMEM;

        match = of_match_device(dev->driver->of_match_table, dev);
        if (!match || !match->data) {
                dev_err(dev, "phy configs are not assigned!\n");
                return -EINVAL;
        }

        if (!dev->parent || !dev->parent->of_node)
                return -EINVAL;

        rphy->grf = syscon_node_to_regmap(dev->parent->of_node);
        if (IS_ERR(rphy->grf))
                return PTR_ERR(rphy->grf);

        if (of_property_read_u32(np, "reg", &reg)) {
                dev_err(dev, "the reg property is not assigned in %s node\n",
                        np->name);
                return -EINVAL;
        }

        rphy->dev = dev;
        phy_cfgs = match->data;
        rphy->chg_state = USB_CHG_STATE_UNDEFINED;
        rphy->chg_type = POWER_SUPPLY_TYPE_UNKNOWN;
        platform_set_drvdata(pdev, rphy);

        ret = rockchip_usb2phy_extcon_register(rphy);
        if (ret)
                return ret;

        /* find out a proper config which can be matched with dt. */
        index = 0;
        while (phy_cfgs[index].reg) {
                if (phy_cfgs[index].reg == reg) {
                        rphy->phy_cfg = &phy_cfgs[index];
                        break;
                }

                ++index;
        }

        if (!rphy->phy_cfg) {
                dev_err(dev, "no phy-config can be matched with %s node\n",
                        np->name);
                return -EINVAL;
        }

        rphy->clk = of_clk_get_by_name(np, "phyclk");
        if (!IS_ERR(rphy->clk)) {
                clk_prepare_enable(rphy->clk);
        } else {
                dev_info(&pdev->dev, "no phyclk specified\n");
                rphy->clk = NULL;
        }

        ret = rockchip_usb2phy_clk480m_register(rphy);
        if (ret) {
                dev_err(dev, "failed to register 480m output clock\n");
                goto disable_clks;
        }

        index = 0;
        for_each_available_child_of_node(np, child_np) {
                struct rockchip_usb2phy_port *rport = &rphy->ports[index];
                struct phy *phy;

                /* This driver aims to support both otg-port and host-port */
                if (of_node_cmp(child_np->name, "host-port") &&
                    of_node_cmp(child_np->name, "otg-port"))
                        goto next_child;

                phy = devm_phy_create(dev, child_np, &rockchip_usb2phy_ops);
                if (IS_ERR(phy)) {
                        dev_err(dev, "failed to create phy\n");
                        ret = PTR_ERR(phy);
                        goto put_child;
                }

                rport->phy = phy;
                phy_set_drvdata(rport->phy, rport);

                /* initialize otg/host port separately */
                if (!of_node_cmp(child_np->name, "host-port")) {
                        ret = rockchip_usb2phy_host_port_init(rphy, rport,
                                                              child_np);
                        if (ret)
                                goto put_child;
                } else {
                        ret = rockchip_usb2phy_otg_port_init(rphy, rport,
                                                             child_np);
                        if (ret)
                                goto put_child;
                }

next_child:
                /* to prevent out of boundary */
                if (++index >= rphy->phy_cfg->num_ports)
                        break;
        }

        provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
        return PTR_ERR_OR_ZERO(provider);

put_child:
        of_node_put(child_np);
disable_clks:
        if (rphy->clk) {
                clk_disable_unprepare(rphy->clk);
                clk_put(rphy->clk);
        }
        return ret;
}

static const struct rockchip_usb2phy_cfg rk3366_phy_cfgs[] = {
        {
                .reg = 0x700,
                .num_ports      = 2,
                .clkout_ctl     = { 0x0724, 15, 15, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_HOST] = {
                                .phy_sus        = { 0x0728, 15, 0, 0, 0x1d1 },
                                .ls_det_en      = { 0x0680, 4, 4, 0, 1 },
                                .ls_det_st      = { 0x0690, 4, 4, 0, 1 },
                                .ls_det_clr     = { 0x06a0, 4, 4, 0, 1 },
                                .utmi_ls        = { 0x049c, 14, 13, 0, 1 },
                                .utmi_hstdet    = { 0x049c, 12, 12, 0, 1 }
                        }
                },
        },
        { /* sentinel */ }
};

static const struct rockchip_usb2phy_cfg rk3399_phy_cfgs[] = {
        {
                .reg            = 0xe450,
                .num_ports      = 2,
                .clkout_ctl     = { 0xe450, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0xe454, 1, 0, 2, 1 },
                                .bvalid_det_en  = { 0xe3c0, 3, 3, 0, 1 },
                                .bvalid_det_st  = { 0xe3e0, 3, 3, 0, 1 },
                                .bvalid_det_clr = { 0xe3d0, 3, 3, 0, 1 },
                                .utmi_avalid    = { 0xe2ac, 7, 7, 0, 1 },
                                .utmi_bvalid    = { 0xe2ac, 12, 12, 0, 1 },
                        },
                        [USB2PHY_PORT_HOST] = {
                                .phy_sus        = { 0xe458, 1, 0, 0x2, 0x1 },
                                .ls_det_en      = { 0xe3c0, 6, 6, 0, 1 },
                                .ls_det_st      = { 0xe3e0, 6, 6, 0, 1 },
                                .ls_det_clr     = { 0xe3d0, 6, 6, 0, 1 },
                                .utmi_ls        = { 0xe2ac, 22, 21, 0, 1 },
                                .utmi_hstdet    = { 0xe2ac, 23, 23, 0, 1 }
                        }
                },
                .chg_det = {
                        .opmode         = { 0xe454, 3, 0, 5, 1 },
                        .cp_det         = { 0xe2ac, 2, 2, 0, 1 },
                        .dcp_det        = { 0xe2ac, 1, 1, 0, 1 },
                        .dp_det         = { 0xe2ac, 0, 0, 0, 1 },
                        .idm_sink_en    = { 0xe450, 8, 8, 0, 1 },
                        .idp_sink_en    = { 0xe450, 7, 7, 0, 1 },
                        .idp_src_en     = { 0xe450, 9, 9, 0, 1 },
                        .rdm_pdwn_en    = { 0xe450, 10, 10, 0, 1 },
                        .vdm_src_en     = { 0xe450, 12, 12, 0, 1 },
                        .vdp_src_en     = { 0xe450, 11, 11, 0, 1 },
                },
        },
        {
                .reg            = 0xe460,
                .num_ports      = 2,
                .clkout_ctl     = { 0xe460, 4, 4, 1, 0 },
                .port_cfgs      = {
                        [USB2PHY_PORT_OTG] = {
                                .phy_sus        = { 0xe464, 1, 0, 2, 1 },
                                .bvalid_det_en  = { 0xe3c0, 8, 8, 0, 1 },
                                .bvalid_det_st  = { 0xe3e0, 8, 8, 0, 1 },
                                .bvalid_det_clr = { 0xe3d0, 8, 8, 0, 1 },
                                .utmi_avalid    = { 0xe2ac, 10, 10, 0, 1 },
                                .utmi_bvalid    = { 0xe2ac, 16, 16, 0, 1 },
                        },
                        [USB2PHY_PORT_HOST] = {
                                .phy_sus        = { 0xe468, 1, 0, 0x2, 0x1 },
                                .ls_det_en      = { 0xe3c0, 11, 11, 0, 1 },
                                .ls_det_st      = { 0xe3e0, 11, 11, 0, 1 },
                                .ls_det_clr     = { 0xe3d0, 11, 11, 0, 1 },
                                .utmi_ls        = { 0xe2ac, 26, 25, 0, 1 },
                                .utmi_hstdet    = { 0xe2ac, 27, 27, 0, 1 }
                        }
                },
        },
        { /* sentinel */ }
};

static const struct of_device_id rockchip_usb2phy_dt_match[] = {
        { .compatible = "rockchip,rk3366-usb2phy", .data = &rk3366_phy_cfgs },
        { .compatible = "rockchip,rk3399-usb2phy", .data = &rk3399_phy_cfgs },
        {}
};
MODULE_DEVICE_TABLE(of, rockchip_usb2phy_dt_match);

static struct platform_driver rockchip_usb2phy_driver = {
        .probe          = rockchip_usb2phy_probe,
        .driver         = {
                .name   = "rockchip-usb2phy",
                .of_match_table = rockchip_usb2phy_dt_match,
        },
};
module_platform_driver(rockchip_usb2phy_driver);

MODULE_AUTHOR("Frank Wang <frank.wang@rock-chips.com>");
MODULE_DESCRIPTION("Rockchip USB2.0 PHY driver");
MODULE_LICENSE("GPL v2");