// SPDX-License-Identifier: GPL-2.0+
/*
 * USB transceiver driver for AB8500 family chips
 *
 * Copyright (C) 2010-2013 ST-Ericsson AB
 * Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
 * Avinash Kumar <avinash.kumar@stericsson.com>
 * Thirupathi Chippakurthy <thirupathi.chippakurthy@stericsson.com>
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/usb/otg.h>
#include <linux/slab.h>
#include <linux/notifier.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/mfd/abx500.h>
#include <linux/mfd/abx500/ab8500.h>
#include <linux/usb/musb-ux500.h>
#include <linux/regulator/consumer.h>
#include <linux/pinctrl/consumer.h>

/* Bank AB8500_SYS_CTRL2_BLOCK */
#define AB8500_MAIN_WD_CTRL_REG 0x01

/* Bank AB8500_USB */
#define AB8500_USB_LINE_STAT_REG 0x80
#define AB8505_USB_LINE_STAT_REG 0x94
#define AB8500_USB_PHY_CTRL_REG 0x8A

/* Bank AB8500_DEVELOPMENT */
#define AB8500_BANK12_ACCESS 0x00

/* Bank AB8500_DEBUG */
#define AB8500_USB_PHY_TUNE1 0x05
#define AB8500_USB_PHY_TUNE2 0x06
#define AB8500_USB_PHY_TUNE3 0x07

/* Bank AB8500_INTERRUPT */
#define AB8500_IT_SOURCE2_REG 0x01

#define AB8500_BIT_OTG_STAT_ID (1 << 0)
#define AB8500_BIT_PHY_CTRL_HOST_EN (1 << 0)
#define AB8500_BIT_PHY_CTRL_DEVICE_EN (1 << 1)
#define AB8500_BIT_WD_CTRL_ENABLE (1 << 0)
#define AB8500_BIT_WD_CTRL_KICK (1 << 1)
#define AB8500_BIT_SOURCE2_VBUSDET (1 << 7)

#define AB8500_WD_KICK_DELAY_US 100 /* usec */
#define AB8500_WD_V11_DISABLE_DELAY_US 100 /* usec */
#define AB8500_V20_31952_DISABLE_DELAY_US 100 /* usec */

/* Usb line status register */
enum ab8500_usb_link_status {
        USB_LINK_NOT_CONFIGURED_8500 = 0,
        USB_LINK_STD_HOST_NC_8500,
        USB_LINK_STD_HOST_C_NS_8500,
        USB_LINK_STD_HOST_C_S_8500,
        USB_LINK_HOST_CHG_NM_8500,
        USB_LINK_HOST_CHG_HS_8500,
        USB_LINK_HOST_CHG_HS_CHIRP_8500,
        USB_LINK_DEDICATED_CHG_8500,
        USB_LINK_ACA_RID_A_8500,
        USB_LINK_ACA_RID_B_8500,
        USB_LINK_ACA_RID_C_NM_8500,
        USB_LINK_ACA_RID_C_HS_8500,
        USB_LINK_ACA_RID_C_HS_CHIRP_8500,
        USB_LINK_HM_IDGND_8500,
        USB_LINK_RESERVED_8500,
        USB_LINK_NOT_VALID_LINK_8500,
};

enum ab8505_usb_link_status {
        USB_LINK_NOT_CONFIGURED_8505 = 0,
        USB_LINK_STD_HOST_NC_8505,
        USB_LINK_STD_HOST_C_NS_8505,
        USB_LINK_STD_HOST_C_S_8505,
        USB_LINK_CDP_8505,
        USB_LINK_RESERVED0_8505,
        USB_LINK_RESERVED1_8505,
        USB_LINK_DEDICATED_CHG_8505,
        USB_LINK_ACA_RID_A_8505,
        USB_LINK_ACA_RID_B_8505,
        USB_LINK_ACA_RID_C_NM_8505,
        USB_LINK_RESERVED2_8505,
        USB_LINK_RESERVED3_8505,
        USB_LINK_HM_IDGND_8505,
        USB_LINK_CHARGERPORT_NOT_OK_8505,
        USB_LINK_CHARGER_DM_HIGH_8505,
        USB_LINK_PHYEN_NO_VBUS_NO_IDGND_8505,
        USB_LINK_STD_UPSTREAM_NO_IDGNG_NO_VBUS_8505,
        USB_LINK_STD_UPSTREAM_8505,
        USB_LINK_CHARGER_SE1_8505,
        USB_LINK_CARKIT_CHGR_1_8505,
        USB_LINK_CARKIT_CHGR_2_8505,
        USB_LINK_ACA_DOCK_CHGR_8505,
        USB_LINK_SAMSUNG_BOOT_CBL_PHY_EN_8505,
        USB_LINK_SAMSUNG_BOOT_CBL_PHY_DISB_8505,
        USB_LINK_SAMSUNG_UART_CBL_PHY_EN_8505,
        USB_LINK_SAMSUNG_UART_CBL_PHY_DISB_8505,
        USB_LINK_MOTOROLA_FACTORY_CBL_PHY_EN_8505,
};

enum ab8500_usb_mode {
        USB_IDLE = 0,
        USB_PERIPHERAL,
        USB_HOST,
        USB_DEDICATED_CHG,
        USB_UART
};

/* Register USB_LINK_STATUS interrupt */
#define AB8500_USB_FLAG_USE_LINK_STATUS_IRQ     (1 << 0)
/* Register ID_WAKEUP_F interrupt */
#define AB8500_USB_FLAG_USE_ID_WAKEUP_IRQ       (1 << 1)
/* Register VBUS_DET_F interrupt */
#define AB8500_USB_FLAG_USE_VBUS_DET_IRQ        (1 << 2)
/* Driver is using the ab-iddet driver*/
#define AB8500_USB_FLAG_USE_AB_IDDET            (1 << 3)
/* Enable setting regulators voltage */
#define AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE   (1 << 4)

struct ab8500_usb {
        struct usb_phy phy;
        struct device *dev;
        struct ab8500 *ab8500;
        unsigned vbus_draw;
        struct work_struct phy_dis_work;
        enum ab8500_usb_mode mode;
        struct clk *sysclk;
        struct regulator *v_ape;
        struct regulator *v_musb;
        struct regulator *v_ulpi;
        int saved_v_ulpi;
        int previous_link_status_state;
        struct pinctrl *pinctrl;
        struct pinctrl_state *pins_sleep;
        bool enabled_charging_detection;
        unsigned int flags;
};

static inline struct ab8500_usb *phy_to_ab(struct usb_phy *x)
{
        return container_of(x, struct ab8500_usb, phy);
}

static void ab8500_usb_wd_workaround(struct ab8500_usb *ab)
{
        abx500_set_register_interruptible(ab->dev,
                AB8500_SYS_CTRL2_BLOCK,
                AB8500_MAIN_WD_CTRL_REG,
                AB8500_BIT_WD_CTRL_ENABLE);

        udelay(AB8500_WD_KICK_DELAY_US);

        abx500_set_register_interruptible(ab->dev,
                AB8500_SYS_CTRL2_BLOCK,
                AB8500_MAIN_WD_CTRL_REG,
                (AB8500_BIT_WD_CTRL_ENABLE
                | AB8500_BIT_WD_CTRL_KICK));

        udelay(AB8500_WD_V11_DISABLE_DELAY_US);

        abx500_set_register_interruptible(ab->dev,
                AB8500_SYS_CTRL2_BLOCK,
                AB8500_MAIN_WD_CTRL_REG,
                0);
}

static void ab8500_usb_regulator_enable(struct ab8500_usb *ab)
{
        int ret, volt;

        ret = regulator_enable(ab->v_ape);
        if (ret)
                dev_err(ab->dev, "Failed to enable v-ape\n");

        if (ab->flags & AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE) {
                ab->saved_v_ulpi = regulator_get_voltage(ab->v_ulpi);
                if (ab->saved_v_ulpi < 0)
                        dev_err(ab->dev, "Failed to get v_ulpi voltage\n");

                ret = regulator_set_voltage(ab->v_ulpi, 1300000, 1350000);
                if (ret < 0)
                        dev_err(ab->dev, "Failed to set the Vintcore to 1.3V, ret=%d\n",
                                        ret);

                ret = regulator_set_load(ab->v_ulpi, 28000);
                if (ret < 0)
                        dev_err(ab->dev, "Failed to set optimum mode (ret=%d)\n",
                                        ret);
        }

        ret = regulator_enable(ab->v_ulpi);
        if (ret)
                dev_err(ab->dev, "Failed to enable vddulpivio18\n");

        if (ab->flags & AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE) {
                volt = regulator_get_voltage(ab->v_ulpi);
                if ((volt != 1300000) && (volt != 1350000))
                        dev_err(ab->dev, "Vintcore is not set to 1.3V volt=%d\n",
                                        volt);
        }

        ret = regulator_enable(ab->v_musb);
        if (ret)
                dev_err(ab->dev, "Failed to enable musb_1v8\n");
}

static void ab8500_usb_regulator_disable(struct ab8500_usb *ab)
{
        int ret;

        regulator_disable(ab->v_musb);

        regulator_disable(ab->v_ulpi);

        /* USB is not the only consumer of Vintcore, restore old settings */
        if (ab->flags & AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE) {
                if (ab->saved_v_ulpi > 0) {
                        ret = regulator_set_voltage(ab->v_ulpi,
                                        ab->saved_v_ulpi, ab->saved_v_ulpi);
                        if (ret < 0)
                                dev_err(ab->dev, "Failed to set the Vintcore to %duV, ret=%d\n",
                                                ab->saved_v_ulpi, ret);
                }

                ret = regulator_set_load(ab->v_ulpi, 0);
                if (ret < 0)
                        dev_err(ab->dev, "Failed to set optimum mode (ret=%d)\n",
                                        ret);
        }

        regulator_disable(ab->v_ape);
}

static void ab8500_usb_wd_linkstatus(struct ab8500_usb *ab, u8 bit)
{
        /* Workaround for v2.0 bug # 31952 */
        if (is_ab8500_2p0(ab->ab8500)) {
                abx500_mask_and_set_register_interruptible(ab->dev,
                                AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                                bit, bit);
                udelay(AB8500_V20_31952_DISABLE_DELAY_US);
        }
}

static void ab8500_usb_phy_enable(struct ab8500_usb *ab, bool sel_host)
{
        u8 bit;
        bit = sel_host ? AB8500_BIT_PHY_CTRL_HOST_EN :
                AB8500_BIT_PHY_CTRL_DEVICE_EN;

        /* mux and configure USB pins to DEFAULT state */
        ab->pinctrl = pinctrl_get_select(ab->dev, PINCTRL_STATE_DEFAULT);
        if (IS_ERR(ab->pinctrl))
                dev_err(ab->dev, "could not get/set default pinstate\n");

        if (clk_prepare_enable(ab->sysclk))
                dev_err(ab->dev, "can't prepare/enable clock\n");

        ab8500_usb_regulator_enable(ab);

        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        bit, bit);
}

static void ab8500_usb_phy_disable(struct ab8500_usb *ab, bool sel_host)
{
        u8 bit;
        bit = sel_host ? AB8500_BIT_PHY_CTRL_HOST_EN :
                AB8500_BIT_PHY_CTRL_DEVICE_EN;

        ab8500_usb_wd_linkstatus(ab, bit);

        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        bit, 0);

        /* Needed to disable the phy.*/
        ab8500_usb_wd_workaround(ab);

        clk_disable_unprepare(ab->sysclk);

        ab8500_usb_regulator_disable(ab);

        if (!IS_ERR(ab->pinctrl)) {
                /* configure USB pins to SLEEP state */
                ab->pins_sleep = pinctrl_lookup_state(ab->pinctrl,
                                PINCTRL_STATE_SLEEP);

                if (IS_ERR(ab->pins_sleep))
                        dev_dbg(ab->dev, "could not get sleep pinstate\n");
                else if (pinctrl_select_state(ab->pinctrl, ab->pins_sleep))
                        dev_err(ab->dev, "could not set pins to sleep state\n");

                /*
                 * as USB pins are shared with iddet, release them to allow
                 * iddet to request them
                 */
                pinctrl_put(ab->pinctrl);
        }
}

#define ab8500_usb_host_phy_en(ab)      ab8500_usb_phy_enable(ab, true)
#define ab8500_usb_host_phy_dis(ab)     ab8500_usb_phy_disable(ab, true)
#define ab8500_usb_peri_phy_en(ab)      ab8500_usb_phy_enable(ab, false)
#define ab8500_usb_peri_phy_dis(ab)     ab8500_usb_phy_disable(ab, false)

static int ab8505_usb_link_status_update(struct ab8500_usb *ab,
                enum ab8505_usb_link_status lsts)
{
        enum ux500_musb_vbus_id_status event = 0;

        dev_dbg(ab->dev, "ab8505_usb_link_status_update %d\n", lsts);

        /*
         * Spurious link_status interrupts are seen at the time of
         * disconnection of a device in RIDA state
         */
        if (ab->previous_link_status_state == USB_LINK_ACA_RID_A_8505 &&
                        (lsts == USB_LINK_STD_HOST_NC_8505))
                return 0;

        ab->previous_link_status_state = lsts;

        switch (lsts) {
        case USB_LINK_ACA_RID_B_8505:
                event = UX500_MUSB_RIDB;
                fallthrough;
        case USB_LINK_NOT_CONFIGURED_8505:
        case USB_LINK_RESERVED0_8505:
        case USB_LINK_RESERVED1_8505:
        case USB_LINK_RESERVED2_8505:
        case USB_LINK_RESERVED3_8505:
                ab->mode = USB_IDLE;
                ab->phy.otg->default_a = false;
                ab->vbus_draw = 0;
                if (event != UX500_MUSB_RIDB)
                        event = UX500_MUSB_NONE;
                /*
                 * Fallback to default B_IDLE as nothing
                 * is connected
                 */
                ab->phy.otg->state = OTG_STATE_B_IDLE;
                usb_phy_set_event(&ab->phy, USB_EVENT_NONE);
                break;

        case USB_LINK_ACA_RID_C_NM_8505:
                event = UX500_MUSB_RIDC;
                fallthrough;
        case USB_LINK_STD_HOST_NC_8505:
        case USB_LINK_STD_HOST_C_NS_8505:
        case USB_LINK_STD_HOST_C_S_8505:
        case USB_LINK_CDP_8505:
                if (ab->mode == USB_IDLE) {
                        ab->mode = USB_PERIPHERAL;
                        ab8500_usb_peri_phy_en(ab);
                        atomic_notifier_call_chain(&ab->phy.notifier,
                                        UX500_MUSB_PREPARE, &ab->vbus_draw);
                        usb_phy_set_event(&ab->phy, USB_EVENT_ENUMERATED);
                }
                if (event != UX500_MUSB_RIDC)
                        event = UX500_MUSB_VBUS;
                break;

        case USB_LINK_ACA_RID_A_8505:
        case USB_LINK_ACA_DOCK_CHGR_8505:
                event = UX500_MUSB_RIDA;
                fallthrough;
        case USB_LINK_HM_IDGND_8505:
                if (ab->mode == USB_IDLE) {
                        ab->mode = USB_HOST;
                        ab8500_usb_host_phy_en(ab);
                        atomic_notifier_call_chain(&ab->phy.notifier,
                                        UX500_MUSB_PREPARE, &ab->vbus_draw);
                }
                ab->phy.otg->default_a = true;
                if (event != UX500_MUSB_RIDA)
                        event = UX500_MUSB_ID;
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                break;

        case USB_LINK_DEDICATED_CHG_8505:
                ab->mode = USB_DEDICATED_CHG;
                event = UX500_MUSB_CHARGER;
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                usb_phy_set_event(&ab->phy, USB_EVENT_CHARGER);
                break;

        /*
         * FIXME: For now we rely on the boot firmware to set up the necessary
         * PHY/pin configuration for UART mode.
         *
         * AB8505 does not seem to report any status change for UART cables,
         * possibly because it cannot detect them autonomously.
         * We may need to measure the ID resistance manually to reliably
         * detect UART cables after bootup.
         */
        case USB_LINK_SAMSUNG_UART_CBL_PHY_EN_8505:
        case USB_LINK_SAMSUNG_UART_CBL_PHY_DISB_8505:
                if (ab->mode == USB_IDLE) {
                        ab->mode = USB_UART;
                        ab8500_usb_peri_phy_en(ab);
                }

                break;

        default:
                break;
        }

        return 0;
}

static int ab8500_usb_link_status_update(struct ab8500_usb *ab,
                enum ab8500_usb_link_status lsts)
{
        enum ux500_musb_vbus_id_status event = 0;

        dev_dbg(ab->dev, "ab8500_usb_link_status_update %d\n", lsts);

        /*
         * Spurious link_status interrupts are seen in case of a
         * disconnection of a device in IDGND and RIDA stage
         */
        if (ab->previous_link_status_state == USB_LINK_HM_IDGND_8500 &&
                        (lsts == USB_LINK_STD_HOST_C_NS_8500 ||
                         lsts == USB_LINK_STD_HOST_NC_8500))
                return 0;

        if (ab->previous_link_status_state == USB_LINK_ACA_RID_A_8500 &&
                        lsts == USB_LINK_STD_HOST_NC_8500)
                return 0;

        ab->previous_link_status_state = lsts;

        switch (lsts) {
        case USB_LINK_ACA_RID_B_8500:
                event = UX500_MUSB_RIDB;
                fallthrough;
        case USB_LINK_NOT_CONFIGURED_8500:
        case USB_LINK_NOT_VALID_LINK_8500:
                ab->mode = USB_IDLE;
                ab->phy.otg->default_a = false;
                ab->vbus_draw = 0;
                if (event != UX500_MUSB_RIDB)
                        event = UX500_MUSB_NONE;
                /* Fallback to default B_IDLE as nothing is connected */
                ab->phy.otg->state = OTG_STATE_B_IDLE;
                usb_phy_set_event(&ab->phy, USB_EVENT_NONE);
                break;

        case USB_LINK_ACA_RID_C_NM_8500:
        case USB_LINK_ACA_RID_C_HS_8500:
        case USB_LINK_ACA_RID_C_HS_CHIRP_8500:
                event = UX500_MUSB_RIDC;
                fallthrough;
        case USB_LINK_STD_HOST_NC_8500:
        case USB_LINK_STD_HOST_C_NS_8500:
        case USB_LINK_STD_HOST_C_S_8500:
        case USB_LINK_HOST_CHG_NM_8500:
        case USB_LINK_HOST_CHG_HS_8500:
        case USB_LINK_HOST_CHG_HS_CHIRP_8500:
                if (ab->mode == USB_IDLE) {
                        ab->mode = USB_PERIPHERAL;
                        ab8500_usb_peri_phy_en(ab);
                        atomic_notifier_call_chain(&ab->phy.notifier,
                                        UX500_MUSB_PREPARE, &ab->vbus_draw);
                        usb_phy_set_event(&ab->phy, USB_EVENT_ENUMERATED);
                }
                if (event != UX500_MUSB_RIDC)
                        event = UX500_MUSB_VBUS;
                break;

        case USB_LINK_ACA_RID_A_8500:
                event = UX500_MUSB_RIDA;
                fallthrough;
        case USB_LINK_HM_IDGND_8500:
                if (ab->mode == USB_IDLE) {
                        ab->mode = USB_HOST;
                        ab8500_usb_host_phy_en(ab);
                        atomic_notifier_call_chain(&ab->phy.notifier,
                                        UX500_MUSB_PREPARE, &ab->vbus_draw);
                }
                ab->phy.otg->default_a = true;
                if (event != UX500_MUSB_RIDA)
                        event = UX500_MUSB_ID;
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                break;

        case USB_LINK_DEDICATED_CHG_8500:
                ab->mode = USB_DEDICATED_CHG;
                event = UX500_MUSB_CHARGER;
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                usb_phy_set_event(&ab->phy, USB_EVENT_CHARGER);
                break;

        case USB_LINK_RESERVED_8500:
                break;
        }

        return 0;
}

/*
 * Connection Sequence:
 *   1. Link Status Interrupt
 *   2. Enable AB clock
 *   3. Enable AB regulators
 *   4. Enable USB phy
 *   5. Reset the musb controller
 *   6. Switch the ULPI GPIO pins to function mode
 *   7. Enable the musb Peripheral5 clock
 *   8. Restore MUSB context
 */
static int abx500_usb_link_status_update(struct ab8500_usb *ab)
{
        u8 reg;
        int ret = 0;

        if (is_ab8500(ab->ab8500)) {
                enum ab8500_usb_link_status lsts;

                ret = abx500_get_register_interruptible(ab->dev,
                                AB8500_USB, AB8500_USB_LINE_STAT_REG, &reg);
                if (ret < 0)
                        return ret;
                lsts = (reg >> 3) & 0x0F;
                ret = ab8500_usb_link_status_update(ab, lsts);
        } else if (is_ab8505(ab->ab8500)) {
                enum ab8505_usb_link_status lsts;

                ret = abx500_get_register_interruptible(ab->dev,
                                AB8500_USB, AB8505_USB_LINE_STAT_REG, &reg);
                if (ret < 0)
                        return ret;
                lsts = (reg >> 3) & 0x1F;
                ret = ab8505_usb_link_status_update(ab, lsts);
        }

        return ret;
}

/*
 * Disconnection Sequence:
 *   1. Disconnect Interrupt
 *   2. Disable regulators
 *   3. Disable AB clock
 *   4. Disable the Phy
 *   5. Link Status Interrupt
 *   6. Disable Musb Clock
 */
static irqreturn_t ab8500_usb_disconnect_irq(int irq, void *data)
{
        struct ab8500_usb *ab = (struct ab8500_usb *) data;
        enum usb_phy_events event = USB_EVENT_NONE;

        /* Link status will not be updated till phy is disabled. */
        if (ab->mode == USB_HOST) {
                ab->phy.otg->default_a = false;
                ab->vbus_draw = 0;
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                ab8500_usb_host_phy_dis(ab);
                ab->mode = USB_IDLE;
        }

        if (ab->mode == USB_PERIPHERAL) {
                atomic_notifier_call_chain(&ab->phy.notifier,
                                event, &ab->vbus_draw);
                ab8500_usb_peri_phy_dis(ab);
                atomic_notifier_call_chain(&ab->phy.notifier,
                                UX500_MUSB_CLEAN, &ab->vbus_draw);
                ab->mode = USB_IDLE;
                ab->phy.otg->default_a = false;
                ab->vbus_draw = 0;
        }

        if (ab->mode == USB_UART) {
                ab8500_usb_peri_phy_dis(ab);
                ab->mode = USB_IDLE;
        }

        if (is_ab8500_2p0(ab->ab8500)) {
                if (ab->mode == USB_DEDICATED_CHG) {
                        ab8500_usb_wd_linkstatus(ab,
                                        AB8500_BIT_PHY_CTRL_DEVICE_EN);
                        abx500_mask_and_set_register_interruptible(ab->dev,
                                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                                        AB8500_BIT_PHY_CTRL_DEVICE_EN, 0);
                }
        }

        return IRQ_HANDLED;
}

static irqreturn_t ab8500_usb_link_status_irq(int irq, void *data)
{
        struct ab8500_usb *ab = (struct ab8500_usb *)data;

        abx500_usb_link_status_update(ab);

        return IRQ_HANDLED;
}

static void ab8500_usb_phy_disable_work(struct work_struct *work)
{
        struct ab8500_usb *ab = container_of(work, struct ab8500_usb,
                                                phy_dis_work);

        if (!ab->phy.otg->host)
                ab8500_usb_host_phy_dis(ab);

        if (!ab->phy.otg->gadget)
                ab8500_usb_peri_phy_dis(ab);
}

static int ab8500_usb_set_suspend(struct usb_phy *x, int suspend)
{
        /* TODO */
        return 0;
}

static int ab8500_usb_set_peripheral(struct usb_otg *otg,
                                        struct usb_gadget *gadget)
{
        struct ab8500_usb *ab;

        if (!otg)
                return -ENODEV;

        ab = phy_to_ab(otg->usb_phy);

        ab->phy.otg->gadget = gadget;

        /* Some drivers call this function in atomic context.
         * Do not update ab8500 registers directly till this
         * is fixed.
         */

        if ((ab->mode != USB_IDLE) && !gadget) {
                ab->mode = USB_IDLE;
                schedule_work(&ab->phy_dis_work);
        }

        return 0;
}

static int ab8500_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
{
        struct ab8500_usb *ab;

        if (!otg)
                return -ENODEV;

        ab = phy_to_ab(otg->usb_phy);

        ab->phy.otg->host = host;

        /* Some drivers call this function in atomic context.
         * Do not update ab8500 registers directly till this
         * is fixed.
         */

        if ((ab->mode != USB_IDLE) && !host) {
                ab->mode = USB_IDLE;
                schedule_work(&ab->phy_dis_work);
        }

        return 0;
}

static void ab8500_usb_restart_phy(struct ab8500_usb *ab)
{
        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        AB8500_BIT_PHY_CTRL_DEVICE_EN,
                        AB8500_BIT_PHY_CTRL_DEVICE_EN);

        udelay(100);

        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        AB8500_BIT_PHY_CTRL_DEVICE_EN,
                        0);

        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        AB8500_BIT_PHY_CTRL_HOST_EN,
                        AB8500_BIT_PHY_CTRL_HOST_EN);

        udelay(100);

        abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_USB, AB8500_USB_PHY_CTRL_REG,
                        AB8500_BIT_PHY_CTRL_HOST_EN,
                        0);
}

static int ab8500_usb_regulator_get(struct ab8500_usb *ab)
{
        int err;

        ab->v_ape = devm_regulator_get(ab->dev, "v-ape");
        if (IS_ERR(ab->v_ape)) {
                dev_err(ab->dev, "Could not get v-ape supply\n");
                err = PTR_ERR(ab->v_ape);
                return err;
        }

        ab->v_ulpi = devm_regulator_get(ab->dev, "vddulpivio18");
        if (IS_ERR(ab->v_ulpi)) {
                dev_err(ab->dev, "Could not get vddulpivio18 supply\n");
                err = PTR_ERR(ab->v_ulpi);
                return err;
        }

        ab->v_musb = devm_regulator_get(ab->dev, "musb_1v8");
        if (IS_ERR(ab->v_musb)) {
                dev_err(ab->dev, "Could not get musb_1v8 supply\n");
                err = PTR_ERR(ab->v_musb);
                return err;
        }

        return 0;
}

static int ab8500_usb_irq_setup(struct platform_device *pdev,
                struct ab8500_usb *ab)
{
        int err;
        int irq;

        if (ab->flags & AB8500_USB_FLAG_USE_LINK_STATUS_IRQ) {
                irq = platform_get_irq_byname(pdev, "USB_LINK_STATUS");
                if (irq < 0)
                        return irq;
                err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                ab8500_usb_link_status_irq,
                                IRQF_NO_SUSPEND | IRQF_SHARED | IRQF_ONESHOT,
                                "usb-link-status", ab);
                if (err < 0) {
                        dev_err(ab->dev, "request_irq failed for link status irq\n");
                        return err;
                }
        }

        if (ab->flags & AB8500_USB_FLAG_USE_ID_WAKEUP_IRQ) {
                irq = platform_get_irq_byname(pdev, "ID_WAKEUP_F");
                if (irq < 0)
                        return irq;
                err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                ab8500_usb_disconnect_irq,
                                IRQF_NO_SUSPEND | IRQF_SHARED | IRQF_ONESHOT,
                                "usb-id-fall", ab);
                if (err < 0) {
                        dev_err(ab->dev, "request_irq failed for ID fall irq\n");
                        return err;
                }
        }

        if (ab->flags & AB8500_USB_FLAG_USE_VBUS_DET_IRQ) {
                irq = platform_get_irq_byname(pdev, "VBUS_DET_F");
                if (irq < 0)
                        return irq;
                err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                ab8500_usb_disconnect_irq,
                                IRQF_NO_SUSPEND | IRQF_SHARED | IRQF_ONESHOT,
                                "usb-vbus-fall", ab);
                if (err < 0) {
                        dev_err(ab->dev, "request_irq failed for Vbus fall irq\n");
                        return err;
                }
        }

        return 0;
}

static void ab8500_usb_set_ab8500_tuning_values(struct ab8500_usb *ab)
{
        int err;

        /* Enable the PBT/Bank 0x12 access */
        err = abx500_set_register_interruptible(ab->dev,
                        AB8500_DEVELOPMENT, AB8500_BANK12_ACCESS, 0x01);
        if (err < 0)
                dev_err(ab->dev, "Failed to enable bank12 access err=%d\n",
                                err);

        err = abx500_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE1, 0xC8);
        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE1 register err=%d\n",
                                err);

        err = abx500_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE2, 0x00);
        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE2 register err=%d\n",
                                err);

        err = abx500_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE3, 0x78);
        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE3 register err=%d\n",
                                err);

        /* Switch to normal mode/disable Bank 0x12 access */
        err = abx500_set_register_interruptible(ab->dev,
                        AB8500_DEVELOPMENT, AB8500_BANK12_ACCESS, 0x00);
        if (err < 0)
                dev_err(ab->dev, "Failed to switch bank12 access err=%d\n",
                                err);
}

static void ab8500_usb_set_ab8505_tuning_values(struct ab8500_usb *ab)
{
        int err;

        /* Enable the PBT/Bank 0x12 access */
        err = abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_DEVELOPMENT, AB8500_BANK12_ACCESS,
                        0x01, 0x01);
        if (err < 0)
                dev_err(ab->dev, "Failed to enable bank12 access err=%d\n",
                                err);

        err = abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE1,
                        0xC8, 0xC8);
        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE1 register err=%d\n",
                                err);

        err = abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE2,
                        0x60, 0x60);
        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE2 register err=%d\n",
                                err);

        err = abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_DEBUG, AB8500_USB_PHY_TUNE3,
                        0xFC, 0x80);

        if (err < 0)
                dev_err(ab->dev, "Failed to set PHY_TUNE3 register err=%d\n",
                                err);

        /* Switch to normal mode/disable Bank 0x12 access */
        err = abx500_mask_and_set_register_interruptible(ab->dev,
                        AB8500_DEVELOPMENT, AB8500_BANK12_ACCESS,
                        0x00, 0x00);
        if (err < 0)
                dev_err(ab->dev, "Failed to switch bank12 access err=%d\n",
                                err);
}

static int ab8500_usb_probe(struct platform_device *pdev)
{
        struct ab8500_usb       *ab;
        struct ab8500           *ab8500;
        struct usb_otg          *otg;
        int err;
        int rev;

        ab8500 = dev_get_drvdata(pdev->dev.parent);
        rev = abx500_get_chip_id(&pdev->dev);

        if (is_ab8500_1p1_or_earlier(ab8500)) {
                dev_err(&pdev->dev, "Unsupported AB8500 chip rev=%d\n", rev);
                return -ENODEV;
        }

        ab = devm_kzalloc(&pdev->dev, sizeof(*ab), GFP_KERNEL);
        if (!ab)
                return -ENOMEM;

        otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
        if (!otg)
                return -ENOMEM;

        ab->dev                 = &pdev->dev;
        ab->ab8500              = ab8500;
        ab->phy.dev             = ab->dev;
        ab->phy.otg             = otg;
        ab->phy.label           = "ab8500";
        ab->phy.set_suspend     = ab8500_usb_set_suspend;
        ab->phy.otg->state      = OTG_STATE_UNDEFINED;

        otg->usb_phy            = &ab->phy;
        otg->set_host           = ab8500_usb_set_host;
        otg->set_peripheral     = ab8500_usb_set_peripheral;

        if (is_ab8500(ab->ab8500)) {
                ab->flags |= AB8500_USB_FLAG_USE_LINK_STATUS_IRQ |
                        AB8500_USB_FLAG_USE_ID_WAKEUP_IRQ |
                        AB8500_USB_FLAG_USE_VBUS_DET_IRQ |
                        AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE;
        } else if (is_ab8505(ab->ab8500)) {
                ab->flags |= AB8500_USB_FLAG_USE_LINK_STATUS_IRQ |
                        AB8500_USB_FLAG_USE_ID_WAKEUP_IRQ |
                        AB8500_USB_FLAG_USE_VBUS_DET_IRQ |
                        AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE;
        }

        /* Disable regulator voltage setting for AB8500 <= v2.0 */
        if (is_ab8500_2p0_or_earlier(ab->ab8500))
                ab->flags &= ~AB8500_USB_FLAG_REGULATOR_SET_VOLTAGE;

        platform_set_drvdata(pdev, ab);

        /* all: Disable phy when called from set_host and set_peripheral */
        INIT_WORK(&ab->phy_dis_work, ab8500_usb_phy_disable_work);

        err = ab8500_usb_regulator_get(ab);
        if (err)
                return err;

        ab->sysclk = devm_clk_get(ab->dev, "sysclk");
        if (IS_ERR(ab->sysclk)) {
                dev_err(ab->dev, "Could not get sysclk.\n");
                return PTR_ERR(ab->sysclk);
        }

        err = ab8500_usb_irq_setup(pdev, ab);
        if (err < 0)
                return err;

        err = usb_add_phy(&ab->phy, USB_PHY_TYPE_USB2);
        if (err) {
                dev_err(&pdev->dev, "Can't register transceiver\n");
                return err;
        }

        if (is_ab8500(ab->ab8500) && !is_ab8500_2p0_or_earlier(ab->ab8500))
                /* Phy tuning values for AB8500 > v2.0 */
                ab8500_usb_set_ab8500_tuning_values(ab);
        else if (is_ab8505(ab->ab8500))
                /* Phy tuning values for AB8505 */
                ab8500_usb_set_ab8505_tuning_values(ab);

        /* Needed to enable ID detection. */
        ab8500_usb_wd_workaround(ab);

        /*
         * This is required for usb-link-status to work properly when a
         * cable is connected at boot time.
         */
        ab8500_usb_restart_phy(ab);

        abx500_usb_link_status_update(ab);

        dev_info(&pdev->dev, "revision 0x%2x driver initialized\n", rev);

        return 0;
}

static void ab8500_usb_remove(struct platform_device *pdev)
{
        struct ab8500_usb *ab = platform_get_drvdata(pdev);

        cancel_work_sync(&ab->phy_dis_work);

        usb_remove_phy(&ab->phy);

        if (ab->mode == USB_HOST)
                ab8500_usb_host_phy_dis(ab);
        else if (ab->mode == USB_PERIPHERAL)
                ab8500_usb_peri_phy_dis(ab);
}

static const struct platform_device_id ab8500_usb_devtype[] = {
        { .name = "ab8500-usb", },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, ab8500_usb_devtype);

static struct platform_driver ab8500_usb_driver = {
        .probe          = ab8500_usb_probe,
        .remove         = ab8500_usb_remove,
        .id_table       = ab8500_usb_devtype,
        .driver         = {
                .name   = "abx5x0-usb",
        },
};

static int __init ab8500_usb_init(void)
{
        return platform_driver_register(&ab8500_usb_driver);
}
subsys_initcall(ab8500_usb_init);

static void __exit ab8500_usb_exit(void)
{
        platform_driver_unregister(&ab8500_usb_driver);
}
module_exit(ab8500_usb_exit);

MODULE_AUTHOR("ST-Ericsson AB");
MODULE_DESCRIPTION("AB8500 family usb transceiver driver");
MODULE_LICENSE("GPL");