/*
 * extcon-max8997.c - MAX8997 extcon driver to support MAX8997 MUIC
 *
 *  Copyright (C) 2012 Samsung Electronics
 *  Donggeun Kim <dg77.kim@samsung.com>
 *
 * 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/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/kobject.h>
#include <linux/mfd/max8997.h>
#include <linux/mfd/max8997-private.h>
#include <linux/extcon.h>
#include <linux/irqdomain.h>

#define DEV_NAME                        "max8997-muic"
#define DELAY_MS_DEFAULT                20000           /* unit: millisecond */

enum max8997_muic_adc_debounce_time {
        ADC_DEBOUNCE_TIME_0_5MS = 0,    /* 0.5ms */
        ADC_DEBOUNCE_TIME_10MS,         /* 10ms */
        ADC_DEBOUNCE_TIME_25MS,         /* 25ms */
        ADC_DEBOUNCE_TIME_38_62MS,      /* 38.62ms */
};

struct max8997_muic_irq {
        unsigned int irq;
        const char *name;
        unsigned int virq;
};

static struct max8997_muic_irq muic_irqs[] = {
        { MAX8997_MUICIRQ_ADCError,     "muic-ADCERROR" },
        { MAX8997_MUICIRQ_ADCLow,       "muic-ADCLOW" },
        { MAX8997_MUICIRQ_ADC,          "muic-ADC" },
        { MAX8997_MUICIRQ_VBVolt,       "muic-VBVOLT" },
        { MAX8997_MUICIRQ_DBChg,        "muic-DBCHG" },
        { MAX8997_MUICIRQ_DCDTmr,       "muic-DCDTMR" },
        { MAX8997_MUICIRQ_ChgDetRun,    "muic-CHGDETRUN" },
        { MAX8997_MUICIRQ_ChgTyp,       "muic-CHGTYP" },
        { MAX8997_MUICIRQ_OVP,          "muic-OVP" },
};

/* Define supported cable type */
enum max8997_muic_acc_type {
        MAX8997_MUIC_ADC_GROUND = 0x0,
        MAX8997_MUIC_ADC_MHL,                   /* MHL*/
        MAX8997_MUIC_ADC_REMOTE_S1_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S2_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S3_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S4_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S5_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S6_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S7_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S8_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S9_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S10_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S11_BUTTON,
        MAX8997_MUIC_ADC_REMOTE_S12_BUTTON,
        MAX8997_MUIC_ADC_RESERVED_ACC_1,
        MAX8997_MUIC_ADC_RESERVED_ACC_2,
        MAX8997_MUIC_ADC_RESERVED_ACC_3,
        MAX8997_MUIC_ADC_RESERVED_ACC_4,
        MAX8997_MUIC_ADC_RESERVED_ACC_5,
        MAX8997_MUIC_ADC_CEA936_AUDIO,
        MAX8997_MUIC_ADC_PHONE_POWERED_DEV,
        MAX8997_MUIC_ADC_TTY_CONVERTER,
        MAX8997_MUIC_ADC_UART_CABLE,
        MAX8997_MUIC_ADC_CEA936A_TYPE1_CHG,
        MAX8997_MUIC_ADC_FACTORY_MODE_USB_OFF,  /* JIG-USB-OFF */
        MAX8997_MUIC_ADC_FACTORY_MODE_USB_ON,   /* JIG-USB-ON */
        MAX8997_MUIC_ADC_AV_CABLE_NOLOAD,       /* DESKDOCK */
        MAX8997_MUIC_ADC_CEA936A_TYPE2_CHG,
        MAX8997_MUIC_ADC_FACTORY_MODE_UART_OFF, /* JIG-UART */
        MAX8997_MUIC_ADC_FACTORY_MODE_UART_ON,  /* CARDOCK */
        MAX8997_MUIC_ADC_AUDIO_MODE_REMOTE,
        MAX8997_MUIC_ADC_OPEN,                  /* OPEN */
};

enum max8997_muic_cable_group {
        MAX8997_CABLE_GROUP_ADC = 0,
        MAX8997_CABLE_GROUP_ADC_GND,
        MAX8997_CABLE_GROUP_CHG,
        MAX8997_CABLE_GROUP_VBVOLT,
};

enum max8997_muic_usb_type {
        MAX8997_USB_HOST,
        MAX8997_USB_DEVICE,
};

enum max8997_muic_charger_type {
        MAX8997_CHARGER_TYPE_NONE = 0,
        MAX8997_CHARGER_TYPE_USB,
        MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT,
        MAX8997_CHARGER_TYPE_DEDICATED_CHG,
        MAX8997_CHARGER_TYPE_500MA,
        MAX8997_CHARGER_TYPE_1A,
        MAX8997_CHARGER_TYPE_DEAD_BATTERY = 7,
};

struct max8997_muic_info {
        struct device *dev;
        struct i2c_client *muic;
        struct extcon_dev *edev;
        int prev_cable_type;
        int prev_chg_type;
        u8 status[2];

        int irq;
        struct work_struct irq_work;
        struct mutex mutex;

        struct max8997_muic_platform_data *muic_pdata;
        enum max8997_muic_charger_type pre_charger_type;

        /*
         * Use delayed workqueue to detect cable state and then
         * notify cable state to notifiee/platform through uevent.
         * After completing the booting of platform, the extcon provider
         * driver should notify cable state to upper layer.
         */
        struct delayed_work wq_detcable;

        /*
         * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
         * h/w path of COMP2/COMN1 on CONTROL1 register.
         */
        int path_usb;
        int path_uart;
};

static const unsigned int max8997_extcon_cable[] = {
        EXTCON_USB,
        EXTCON_USB_HOST,
        EXTCON_CHG_USB_SDP,
        EXTCON_CHG_USB_DCP,
        EXTCON_CHG_USB_FAST,
        EXTCON_CHG_USB_SLOW,
        EXTCON_CHG_USB_CDP,
        EXTCON_DISP_MHL,
        EXTCON_DOCK,
        EXTCON_JIG,
        EXTCON_NONE,
};

/*
 * max8997_muic_set_debounce_time - Set the debounce time of ADC
 * @info: the instance including private data of max8997 MUIC
 * @time: the debounce time of ADC
 */
static int max8997_muic_set_debounce_time(struct max8997_muic_info *info,
                enum max8997_muic_adc_debounce_time time)
{
        int ret;

        switch (time) {
        case ADC_DEBOUNCE_TIME_0_5MS:
        case ADC_DEBOUNCE_TIME_10MS:
        case ADC_DEBOUNCE_TIME_25MS:
        case ADC_DEBOUNCE_TIME_38_62MS:
                ret = max8997_update_reg(info->muic,
                                          MAX8997_MUIC_REG_CONTROL3,
                                          time << CONTROL3_ADCDBSET_SHIFT,
                                          CONTROL3_ADCDBSET_MASK);
                if (ret) {
                        dev_err(info->dev, "failed to set ADC debounce time\n");
                        return ret;
                }
                break;
        default:
                dev_err(info->dev, "invalid ADC debounce time\n");
                return -EINVAL;
        }

        return 0;
};

/*
 * max8997_muic_set_path - Set hardware line according to attached cable
 * @info: the instance including private data of max8997 MUIC
 * @value: the path according to attached cable
 * @attached: the state of cable (true:attached, false:detached)
 *
 * The max8997 MUIC device share outside H/W line among a varity of cables,
 * so this function set internal path of H/W line according to the type of
 * attached cable.
 */
static int max8997_muic_set_path(struct max8997_muic_info *info,
                u8 val, bool attached)
{
        int ret = 0;
        u8 ctrl1, ctrl2 = 0;

        if (attached)
                ctrl1 = val;
        else
                ctrl1 = CONTROL1_SW_OPEN;

        ret = max8997_update_reg(info->muic,
                        MAX8997_MUIC_REG_CONTROL1, ctrl1, COMP_SW_MASK);
        if (ret < 0) {
                dev_err(info->dev, "failed to update MUIC register\n");
                return ret;
        }

        if (attached)
                ctrl2 |= CONTROL2_CPEN_MASK;    /* LowPwr=0, CPEn=1 */
        else
                ctrl2 |= CONTROL2_LOWPWR_MASK;  /* LowPwr=1, CPEn=0 */

        ret = max8997_update_reg(info->muic,
                        MAX8997_MUIC_REG_CONTROL2, ctrl2,
                        CONTROL2_LOWPWR_MASK | CONTROL2_CPEN_MASK);
        if (ret < 0) {
                dev_err(info->dev, "failed to update MUIC register\n");
                return ret;
        }

        dev_info(info->dev,
                "CONTROL1 : 0x%02x, CONTROL2 : 0x%02x, state : %s\n",
                ctrl1, ctrl2, attached ? "attached" : "detached");

        return 0;
}

/*
 * max8997_muic_get_cable_type - Return cable type and check cable state
 * @info: the instance including private data of max8997 MUIC
 * @group: the path according to attached cable
 * @attached: store cable state and return
 *
 * This function check the cable state either attached or detached,
 * and then divide precise type of cable according to cable group.
 *      - MAX8997_CABLE_GROUP_ADC
 *      - MAX8997_CABLE_GROUP_CHG
 */
static int max8997_muic_get_cable_type(struct max8997_muic_info *info,
                enum max8997_muic_cable_group group, bool *attached)
{
        int cable_type = 0;
        int adc;
        int chg_type;

        switch (group) {
        case MAX8997_CABLE_GROUP_ADC:
                /*
                 * Read ADC value to check cable type and decide cable state
                 * according to cable type
                 */
                adc = info->status[0] & STATUS1_ADC_MASK;
                adc >>= STATUS1_ADC_SHIFT;

                /*
                 * Check current cable state/cable type and store cable type
                 * (info->prev_cable_type) for handling cable when cable is
                 * detached.
                 */
                if (adc == MAX8997_MUIC_ADC_OPEN) {
                        *attached = false;

                        cable_type = info->prev_cable_type;
                        info->prev_cable_type = MAX8997_MUIC_ADC_OPEN;
                } else {
                        *attached = true;

                        cable_type = info->prev_cable_type = adc;
                }
                break;
        case MAX8997_CABLE_GROUP_CHG:
                /*
                 * Read charger type to check cable type and decide cable state
                 * according to type of charger cable.
                 */
                chg_type = info->status[1] & STATUS2_CHGTYP_MASK;
                chg_type >>= STATUS2_CHGTYP_SHIFT;

                if (chg_type == MAX8997_CHARGER_TYPE_NONE) {
                        *attached = false;

                        cable_type = info->prev_chg_type;
                        info->prev_chg_type = MAX8997_CHARGER_TYPE_NONE;
                } else {
                        *attached = true;

                        /*
                         * Check current cable state/cable type and store cable
                         * type(info->prev_chg_type) for handling cable when
                         * charger cable is detached.
                         */
                        cable_type = info->prev_chg_type = chg_type;
                }

                break;
        default:
                dev_err(info->dev, "Unknown cable group (%d)\n", group);
                cable_type = -EINVAL;
                break;
        }

        return cable_type;
}

static int max8997_muic_handle_usb(struct max8997_muic_info *info,
                        enum max8997_muic_usb_type usb_type, bool attached)
{
        int ret = 0;

        if (usb_type == MAX8997_USB_HOST) {
                ret = max8997_muic_set_path(info, info->path_usb, attached);
                if (ret < 0) {
                        dev_err(info->dev, "failed to update muic register\n");
                        return ret;
                }
        }

        switch (usb_type) {
        case MAX8997_USB_HOST:
                extcon_set_state_sync(info->edev, EXTCON_USB_HOST, attached);
                break;
        case MAX8997_USB_DEVICE:
                extcon_set_state_sync(info->edev, EXTCON_USB, attached);
                extcon_set_state_sync(info->edev, EXTCON_CHG_USB_SDP,
                                        attached);
                break;
        default:
                dev_err(info->dev, "failed to detect %s usb cable\n",
                        attached ? "attached" : "detached");
                return -EINVAL;
        }

        return 0;
}

static int max8997_muic_handle_dock(struct max8997_muic_info *info,
                        int cable_type, bool attached)
{
        int ret = 0;

        ret = max8997_muic_set_path(info, CONTROL1_SW_AUDIO, attached);
        if (ret) {
                dev_err(info->dev, "failed to update muic register\n");
                return ret;
        }

        switch (cable_type) {
        case MAX8997_MUIC_ADC_AV_CABLE_NOLOAD:
        case MAX8997_MUIC_ADC_FACTORY_MODE_UART_ON:
                extcon_set_state_sync(info->edev, EXTCON_DOCK, attached);
                break;
        default:
                dev_err(info->dev, "failed to detect %s dock device\n",
                        attached ? "attached" : "detached");
                return -EINVAL;
        }

        return 0;
}

static int max8997_muic_handle_jig_uart(struct max8997_muic_info *info,
                        bool attached)
{
        int ret = 0;

        /* switch to UART */
        ret = max8997_muic_set_path(info, info->path_uart, attached);
        if (ret) {
                dev_err(info->dev, "failed to update muic register\n");
                return ret;
        }

        extcon_set_state_sync(info->edev, EXTCON_JIG, attached);

        return 0;
}

static int max8997_muic_adc_handler(struct max8997_muic_info *info)
{
        int cable_type;
        bool attached;
        int ret = 0;

        /* Check cable state which is either detached or attached */
        cable_type = max8997_muic_get_cable_type(info,
                                MAX8997_CABLE_GROUP_ADC, &attached);

        switch (cable_type) {
        case MAX8997_MUIC_ADC_GROUND:
                ret = max8997_muic_handle_usb(info, MAX8997_USB_HOST, attached);
                if (ret < 0)
                        return ret;
                break;
        case MAX8997_MUIC_ADC_MHL:
                extcon_set_state_sync(info->edev, EXTCON_DISP_MHL, attached);
                break;
        case MAX8997_MUIC_ADC_FACTORY_MODE_USB_OFF:
        case MAX8997_MUIC_ADC_FACTORY_MODE_USB_ON:
                ret = max8997_muic_handle_usb(info,
                                             MAX8997_USB_DEVICE, attached);
                if (ret < 0)
                        return ret;
                break;
        case MAX8997_MUIC_ADC_AV_CABLE_NOLOAD:
        case MAX8997_MUIC_ADC_FACTORY_MODE_UART_ON:
                ret = max8997_muic_handle_dock(info, cable_type, attached);
                if (ret < 0)
                        return ret;
                break;
        case MAX8997_MUIC_ADC_FACTORY_MODE_UART_OFF:
                ret = max8997_muic_handle_jig_uart(info, attached);
                break;
        case MAX8997_MUIC_ADC_REMOTE_S1_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S2_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S3_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S4_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S5_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S6_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S7_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S8_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S9_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S10_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S11_BUTTON:
        case MAX8997_MUIC_ADC_REMOTE_S12_BUTTON:
        case MAX8997_MUIC_ADC_RESERVED_ACC_1:
        case MAX8997_MUIC_ADC_RESERVED_ACC_2:
        case MAX8997_MUIC_ADC_RESERVED_ACC_3:
        case MAX8997_MUIC_ADC_RESERVED_ACC_4:
        case MAX8997_MUIC_ADC_RESERVED_ACC_5:
        case MAX8997_MUIC_ADC_CEA936_AUDIO:
        case MAX8997_MUIC_ADC_PHONE_POWERED_DEV:
        case MAX8997_MUIC_ADC_TTY_CONVERTER:
        case MAX8997_MUIC_ADC_UART_CABLE:
        case MAX8997_MUIC_ADC_CEA936A_TYPE1_CHG:
        case MAX8997_MUIC_ADC_CEA936A_TYPE2_CHG:
        case MAX8997_MUIC_ADC_AUDIO_MODE_REMOTE:
                /*
                 * This cable isn't used in general case if it is specially
                 * needed to detect additional cable, should implement
                 * proper operation when this cable is attached/detached.
                 */
                dev_info(info->dev,
                        "cable is %s but it isn't used (type:0x%x)\n",
                        attached ? "attached" : "detached", cable_type);
                return -EAGAIN;
        default:
                dev_err(info->dev,
                        "failed to detect %s unknown cable (type:0x%x)\n",
                        attached ? "attached" : "detached", cable_type);
                return -EINVAL;
        }

        return 0;
}

static int max8997_muic_chg_handler(struct max8997_muic_info *info)
{
        int chg_type;
        bool attached;
        int adc;

        chg_type = max8997_muic_get_cable_type(info,
                                MAX8997_CABLE_GROUP_CHG, &attached);

        switch (chg_type) {
        case MAX8997_CHARGER_TYPE_NONE:
                break;
        case MAX8997_CHARGER_TYPE_USB:
                adc = info->status[0] & STATUS1_ADC_MASK;
                adc >>= STATUS1_ADC_SHIFT;

                if ((adc & STATUS1_ADC_MASK) == MAX8997_MUIC_ADC_OPEN) {
                        max8997_muic_handle_usb(info,
                                        MAX8997_USB_DEVICE, attached);
                }
                break;
        case MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT:
                extcon_set_state_sync(info->edev, EXTCON_CHG_USB_CDP,
                                        attached);
                break;
        case MAX8997_CHARGER_TYPE_DEDICATED_CHG:
                extcon_set_state_sync(info->edev, EXTCON_CHG_USB_DCP,
                                        attached);
                break;
        case MAX8997_CHARGER_TYPE_500MA:
                extcon_set_state_sync(info->edev, EXTCON_CHG_USB_SLOW,
                                        attached);
                break;
        case MAX8997_CHARGER_TYPE_1A:
                extcon_set_state_sync(info->edev, EXTCON_CHG_USB_FAST,
                                        attached);
                break;
        default:
                dev_err(info->dev,
                        "failed to detect %s unknown chg cable (type:0x%x)\n",
                        attached ? "attached" : "detached", chg_type);
                return -EINVAL;
        }

        return 0;
}

static void max8997_muic_irq_work(struct work_struct *work)
{
        struct max8997_muic_info *info = container_of(work,
                        struct max8997_muic_info, irq_work);
        int irq_type = 0;
        int i, ret;

        if (!info->edev)
                return;

        mutex_lock(&info->mutex);

        for (i = 0; i < ARRAY_SIZE(muic_irqs); i++)
                if (info->irq == muic_irqs[i].virq)
                        irq_type = muic_irqs[i].irq;

        ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
                                2, info->status);
        if (ret) {
                dev_err(info->dev, "failed to read muic register\n");
                mutex_unlock(&info->mutex);
                return;
        }

        switch (irq_type) {
        case MAX8997_MUICIRQ_ADCError:
        case MAX8997_MUICIRQ_ADCLow:
        case MAX8997_MUICIRQ_ADC:
                /* Handle all of cable except for charger cable */
                ret = max8997_muic_adc_handler(info);
                break;
        case MAX8997_MUICIRQ_VBVolt:
        case MAX8997_MUICIRQ_DBChg:
        case MAX8997_MUICIRQ_DCDTmr:
        case MAX8997_MUICIRQ_ChgDetRun:
        case MAX8997_MUICIRQ_ChgTyp:
                /* Handle charger cable */
                ret = max8997_muic_chg_handler(info);
                break;
        case MAX8997_MUICIRQ_OVP:
                break;
        default:
                dev_info(info->dev, "misc interrupt: irq %d occurred\n",
                                irq_type);
                mutex_unlock(&info->mutex);
                return;
        }

        if (ret < 0)
                dev_err(info->dev, "failed to handle MUIC interrupt\n");

        mutex_unlock(&info->mutex);
}

static irqreturn_t max8997_muic_irq_handler(int irq, void *data)
{
        struct max8997_muic_info *info = data;

        dev_dbg(info->dev, "irq:%d\n", irq);
        info->irq = irq;

        schedule_work(&info->irq_work);

        return IRQ_HANDLED;
}

static int max8997_muic_detect_dev(struct max8997_muic_info *info)
{
        int ret = 0;
        int adc;
        int chg_type;
        bool attached;

        mutex_lock(&info->mutex);

        /* Read STATUSx register to detect accessory */
        ret = max8997_bulk_read(info->muic,
                        MAX8997_MUIC_REG_STATUS1, 2, info->status);
        if (ret) {
                dev_err(info->dev, "failed to read MUIC register\n");
                mutex_unlock(&info->mutex);
                return ret;
        }

        adc = max8997_muic_get_cable_type(info, MAX8997_CABLE_GROUP_ADC,
                                        &attached);
        if (attached && adc != MAX8997_MUIC_ADC_OPEN) {
                ret = max8997_muic_adc_handler(info);
                if (ret < 0) {
                        dev_err(info->dev, "Cannot detect ADC cable\n");
                        mutex_unlock(&info->mutex);
                        return ret;
                }
        }

        chg_type = max8997_muic_get_cable_type(info, MAX8997_CABLE_GROUP_CHG,
                                        &attached);
        if (attached && chg_type != MAX8997_CHARGER_TYPE_NONE) {
                ret = max8997_muic_chg_handler(info);
                if (ret < 0) {
                        dev_err(info->dev, "Cannot detect charger cable\n");
                        mutex_unlock(&info->mutex);
                        return ret;
                }
        }

        mutex_unlock(&info->mutex);

        return 0;
}

static void max8997_muic_detect_cable_wq(struct work_struct *work)
{
        struct max8997_muic_info *info = container_of(to_delayed_work(work),
                                struct max8997_muic_info, wq_detcable);
        int ret;

        ret = max8997_muic_detect_dev(info);
        if (ret < 0)
                dev_err(info->dev, "failed to detect cable type\n");
}

static int max8997_muic_probe(struct platform_device *pdev)
{
        struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
        struct max8997_platform_data *pdata = dev_get_platdata(max8997->dev);
        struct max8997_muic_info *info;
        int delay_jiffies;
        int ret, i;

        info = devm_kzalloc(&pdev->dev, sizeof(struct max8997_muic_info),
                            GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        info->dev = &pdev->dev;
        info->muic = max8997->muic;

        platform_set_drvdata(pdev, info);
        mutex_init(&info->mutex);

        INIT_WORK(&info->irq_work, max8997_muic_irq_work);

        for (i = 0; i < ARRAY_SIZE(muic_irqs); i++) {
                struct max8997_muic_irq *muic_irq = &muic_irqs[i];
                unsigned int virq = 0;

                virq = irq_create_mapping(max8997->irq_domain, muic_irq->irq);
                if (!virq) {
                        ret = -EINVAL;
                        goto err_irq;
                }
                muic_irq->virq = virq;

                ret = request_threaded_irq(virq, NULL,
                                max8997_muic_irq_handler,
                                IRQF_NO_SUSPEND,
                                muic_irq->name, info);
                if (ret) {
                        dev_err(&pdev->dev,
                                "failed: irq request (IRQ: %d, error :%d)\n",
                                muic_irq->irq, ret);
                        goto err_irq;
                }
        }

        /* External connector */
        info->edev = devm_extcon_dev_allocate(&pdev->dev, max8997_extcon_cable);
        if (IS_ERR(info->edev)) {
                dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
                ret = -ENOMEM;
                goto err_irq;
        }

        ret = devm_extcon_dev_register(&pdev->dev, info->edev);
        if (ret) {
                dev_err(&pdev->dev, "failed to register extcon device\n");
                goto err_irq;
        }

        if (pdata && pdata->muic_pdata) {
                struct max8997_muic_platform_data *muic_pdata
                        = pdata->muic_pdata;

                /* Initialize registers according to platform data */
                for (i = 0; i < muic_pdata->num_init_data; i++) {
                        max8997_write_reg(info->muic,
                                        muic_pdata->init_data[i].addr,
                                        muic_pdata->init_data[i].data);
                }

                /*
                 * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
                 * h/w path of COMP2/COMN1 on CONTROL1 register.
                 */
                if (muic_pdata->path_uart)
                        info->path_uart = muic_pdata->path_uart;
                else
                        info->path_uart = CONTROL1_SW_UART;

                if (muic_pdata->path_usb)
                        info->path_usb = muic_pdata->path_usb;
                else
                        info->path_usb = CONTROL1_SW_USB;

                /*
                 * Default delay time for detecting cable state
                 * after certain time.
                 */
                if (muic_pdata->detcable_delay_ms)
                        delay_jiffies =
                                msecs_to_jiffies(muic_pdata->detcable_delay_ms);
                else
                        delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
        } else {
                info->path_uart = CONTROL1_SW_UART;
                info->path_usb = CONTROL1_SW_USB;
                delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
        }

        /* Set initial path for UART */
         max8997_muic_set_path(info, info->path_uart, true);

        /* Set ADC debounce time */
        max8997_muic_set_debounce_time(info, ADC_DEBOUNCE_TIME_25MS);

        /*
         * Detect accessory after completing the initialization of platform
         *
         * - Use delayed workqueue to detect cable state and then
         * notify cable state to notifiee/platform through uevent.
         * After completing the booting of platform, the extcon provider
         * driver should notify cable state to upper layer.
         */
        INIT_DELAYED_WORK(&info->wq_detcable, max8997_muic_detect_cable_wq);
        queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
                        delay_jiffies);

        return 0;

err_irq:
        while (--i >= 0)
                free_irq(muic_irqs[i].virq, info);
        return ret;
}

static int max8997_muic_remove(struct platform_device *pdev)
{
        struct max8997_muic_info *info = platform_get_drvdata(pdev);
        int i;

        for (i = 0; i < ARRAY_SIZE(muic_irqs); i++)
                free_irq(muic_irqs[i].virq, info);
        cancel_work_sync(&info->irq_work);

        return 0;
}

static struct platform_driver max8997_muic_driver = {
        .driver         = {
                .name   = DEV_NAME,
        },
        .probe          = max8997_muic_probe,
        .remove         = max8997_muic_remove,
};

module_platform_driver(max8997_muic_driver);

MODULE_DESCRIPTION("Maxim MAX8997 Extcon driver");
MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
MODULE_LICENSE("GPL");