lp8788-charger.c

Go to the documentation of this file.

/*
 * TI LP8788 MFD - battery charger driver
 *
 * Copyright 2012 Texas Instruments
 *
 * Author: Milo(Woogyom) Kim <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/err.h>
#include <linux/iio/consumer.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/mfd/lp8788.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

/* register address */
#define LP8788_CHG_STATUS       0x07
#define LP8788_CHG_IDCIN        0x13
#define LP8788_CHG_IBATT        0x14
#define LP8788_CHG_VTERM        0x15
#define LP8788_CHG_EOC          0x16

/* mask/shift bits */
#define LP8788_CHG_INPUT_STATE_M    0x03    /* Addr 07h */
#define LP8788_CHG_STATE_M      0x3C
#define LP8788_CHG_STATE_S      2
#define LP8788_NO_BATT_M        BIT(6)
#define LP8788_BAD_BATT_M       BIT(7)
#define LP8788_CHG_IBATT_M      0x1F    /* Addr 14h */
#define LP8788_CHG_VTERM_M      0x0F    /* Addr 15h */
#define LP8788_CHG_EOC_LEVEL_M      0x30    /* Addr 16h */
#define LP8788_CHG_EOC_LEVEL_S      4
#define LP8788_CHG_EOC_TIME_M       0x0E
#define LP8788_CHG_EOC_TIME_S       1
#define LP8788_CHG_EOC_MODE_M       BIT(0)

#define LP8788_CHARGER_NAME     "charger"
#define LP8788_BATTERY_NAME     "main_batt"

#define LP8788_CHG_START        0x11
#define LP8788_CHG_END          0x1C

#define LP8788_BUF_SIZE         40
#define LP8788_ISEL_MAX         23
#define LP8788_ISEL_STEP        50
#define LP8788_VTERM_MIN        4100
#define LP8788_VTERM_STEP       25
#define LP8788_MAX_BATT_CAPACITY    100
#define LP8788_MAX_CHG_IRQS     11

enum lp8788_charging_state {
    LP8788_OFF,
    LP8788_WARM_UP,
    LP8788_LOW_INPUT = 0x3,
    LP8788_PRECHARGE,
    LP8788_CC,
    LP8788_CV,
    LP8788_MAINTENANCE,
    LP8788_BATTERY_FAULT,
    LP8788_SYSTEM_SUPPORT = 0xC,
    LP8788_HIGH_CURRENT = 0xF,
    LP8788_MAX_CHG_STATE,
};

enum lp8788_charger_adc_sel {
    LP8788_VBATT,
    LP8788_BATT_TEMP,
    LP8788_NUM_CHG_ADC,
};

enum lp8788_charger_input_state {
    LP8788_SYSTEM_SUPPLY = 1,
    LP8788_FULL_FUNCTION,
};

/*
 * struct lp8788_chg_irq
 * @which        : lp8788 interrupt id
 * @virq         : Linux IRQ number from irq_domain
 */
struct lp8788_chg_irq {
    enum lp8788_int_id which;
    int virq;
};

/*
 * struct lp8788_charger
 * @lp           : used for accessing the registers of mfd lp8788 device
 * @charger      : power supply driver for the battery charger
 * @battery      : power supply driver for the battery
 * @charger_work : work queue for charger input interrupts
 * @chan         : iio channels for getting adc values
 *                 eg) battery voltage, capacity and temperature
 * @irqs         : charger dedicated interrupts
 * @num_irqs     : total numbers of charger interrupts
 * @pdata        : charger platform specific data
 */
struct lp8788_charger {
    struct lp8788 *lp;
    struct power_supply charger;
    struct power_supply battery;
    struct work_struct charger_work;
    struct iio_channel *chan[LP8788_NUM_CHG_ADC];
    struct lp8788_chg_irq irqs[LP8788_MAX_CHG_IRQS];
    int num_irqs;
    struct lp8788_charger_platform_data *pdata;
};

static char *battery_supplied_to[] = {
    LP8788_BATTERY_NAME,
};

static enum power_supply_property lp8788_charger_prop[] = {
    POWER_SUPPLY_PROP_ONLINE,
    POWER_SUPPLY_PROP_CURRENT_MAX,
};

static enum power_supply_property lp8788_battery_prop[] = {
    POWER_SUPPLY_PROP_STATUS,
    POWER_SUPPLY_PROP_HEALTH,
    POWER_SUPPLY_PROP_PRESENT,
    POWER_SUPPLY_PROP_VOLTAGE_NOW,
    POWER_SUPPLY_PROP_CAPACITY,
    POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
    POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
    POWER_SUPPLY_PROP_TEMP,
};

static bool lp8788_is_charger_detected(struct lp8788_charger *pchg)
{
    u8 data;

    lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
    data &= LP8788_CHG_INPUT_STATE_M;

    return data == LP8788_SYSTEM_SUPPLY || data == LP8788_FULL_FUNCTION;
}

static int lp8788_charger_get_property(struct power_supply *psy,
                    enum power_supply_property psp,
                    union power_supply_propval *val)
{
    struct lp8788_charger *pchg = dev_get_drvdata(psy->dev->parent);
    u8 read;

    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = lp8788_is_charger_detected(pchg);
        break;
    case POWER_SUPPLY_PROP_CURRENT_MAX:
        lp8788_read_byte(pchg->lp, LP8788_CHG_IDCIN, &read);
        val->intval = LP8788_ISEL_STEP *
                (min_t(int, read, LP8788_ISEL_MAX) + 1);
        break;
    default:
        return -EINVAL;
    }

    return 0;
}

static int lp8788_get_battery_status(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    enum lp8788_charging_state state;
    u8 data;
    int ret;

    ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
    if (ret)
        return ret;

    state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;
    switch (state) {
    case LP8788_OFF:
        val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
        break;
    case LP8788_PRECHARGE:
    case LP8788_CC:
    case LP8788_CV:
    case LP8788_HIGH_CURRENT:
        val->intval = POWER_SUPPLY_STATUS_CHARGING;
        break;
    case LP8788_MAINTENANCE:
        val->intval = POWER_SUPPLY_STATUS_FULL;
        break;
    default:
        val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
        break;
    }

    return 0;
}

static int lp8788_get_battery_health(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    u8 data;
    int ret;

    ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
    if (ret)
        return ret;

    if (data & LP8788_NO_BATT_M)
        val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
    else if (data & LP8788_BAD_BATT_M)
        val->intval = POWER_SUPPLY_HEALTH_DEAD;
    else
        val->intval = POWER_SUPPLY_HEALTH_GOOD;

    return 0;
}

static int lp8788_get_battery_present(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    u8 data;
    int ret;

    ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
    if (ret)
        return ret;

    val->intval = !(data & LP8788_NO_BATT_M);
    return 0;
}

static int lp8788_get_vbatt_adc(struct lp8788_charger *pchg,
                unsigned int *result)
{
    struct iio_channel *channel = pchg->chan[LP8788_VBATT];
    int scaleint;
    int scalepart;
    int ret;

    if (!channel)
        return -EINVAL;

    ret = iio_read_channel_scale(channel, &scaleint, &scalepart);
    if (ret != IIO_VAL_INT_PLUS_MICRO)
        return -EINVAL;

    /* unit: mV */
    *result = (scaleint + scalepart * 1000000) / 1000;

    return 0;
}

static int lp8788_get_battery_voltage(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    return lp8788_get_vbatt_adc(pchg, &val->intval);
}

static int lp8788_get_battery_capacity(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    struct lp8788 *lp = pchg->lp;
    struct lp8788_charger_platform_data *pdata = pchg->pdata;
    unsigned int max_vbatt;
    unsigned int vbatt;
    enum lp8788_charging_state state;
    u8 data;
    int ret;

    if (!pdata)
        return -EINVAL;

    max_vbatt = pdata->max_vbatt_mv;
    if (max_vbatt == 0)
        return -EINVAL;

    ret = lp8788_read_byte(lp, LP8788_CHG_STATUS, &data);
    if (ret)
        return ret;

    state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;

    if (state == LP8788_MAINTENANCE) {
        val->intval = LP8788_MAX_BATT_CAPACITY;
    } else {
        ret = lp8788_get_vbatt_adc(pchg, &vbatt);
        if (ret)
            return ret;

        val->intval = (vbatt * LP8788_MAX_BATT_CAPACITY) / max_vbatt;
        val->intval = min(val->intval, LP8788_MAX_BATT_CAPACITY);
    }

    return 0;
}

static int lp8788_get_battery_temperature(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    struct iio_channel *channel = pchg->chan[LP8788_BATT_TEMP];
    int scaleint;
    int scalepart;
    int ret;

    if (!channel)
        return -EINVAL;

    ret = iio_read_channel_scale(channel, &scaleint, &scalepart);
    if (ret != IIO_VAL_INT_PLUS_MICRO)
        return -EINVAL;

    /* unit: 0.1 'C */
    val->intval = (scaleint + scalepart * 1000000) / 100;

    return 0;
}

static int lp8788_get_battery_charging_current(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    u8 read;

    lp8788_read_byte(pchg->lp, LP8788_CHG_IBATT, &read);
    read &= LP8788_CHG_IBATT_M;
    val->intval = LP8788_ISEL_STEP *
            (min_t(int, read, LP8788_ISEL_MAX) + 1);

    return 0;
}

static int lp8788_get_charging_termination_voltage(struct lp8788_charger *pchg,
                union power_supply_propval *val)
{
    u8 read;

    lp8788_read_byte(pchg->lp, LP8788_CHG_VTERM, &read);
    read &= LP8788_CHG_VTERM_M;
    val->intval = LP8788_VTERM_MIN + LP8788_VTERM_STEP * read;

    return 0;
}

static int lp8788_battery_get_property(struct power_supply *psy,
                    enum power_supply_property psp,
                    union power_supply_propval *val)
{
    struct lp8788_charger *pchg = dev_get_drvdata(psy->dev->parent);

    switch (psp) {
    case POWER_SUPPLY_PROP_STATUS:
        return lp8788_get_battery_status(pchg, val);
    case POWER_SUPPLY_PROP_HEALTH:
        return lp8788_get_battery_health(pchg, val);
    case POWER_SUPPLY_PROP_PRESENT:
        return lp8788_get_battery_present(pchg, val);
    case POWER_SUPPLY_PROP_VOLTAGE_NOW:
        return lp8788_get_battery_voltage(pchg, val);
    case POWER_SUPPLY_PROP_CAPACITY:
        return lp8788_get_battery_capacity(pchg, val);
    case POWER_SUPPLY_PROP_TEMP:
        return lp8788_get_battery_temperature(pchg, val);
    case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
        return lp8788_get_battery_charging_current(pchg, val);
    case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
        return lp8788_get_charging_termination_voltage(pchg, val);
    default:
        return -EINVAL;
    }
}

static inline bool lp8788_is_valid_charger_register(u8 addr)
{
    return addr >= LP8788_CHG_START && addr <= LP8788_CHG_END;
}

static int lp8788_update_charger_params(struct lp8788_charger *pchg)
{
    struct lp8788 *lp = pchg->lp;
    struct lp8788_charger_platform_data *pdata = pchg->pdata;
    struct lp8788_chg_param *param;
    int i;
    int ret;

    if (!pdata || !pdata->chg_params) {
        dev_info(lp->dev, "skip updating charger parameters\n");
        return 0;
    }

    /* settting charging parameters */
    for (i = 0; i < pdata->num_chg_params; i++) {
        param = pdata->chg_params + i;

        if (!param)
            continue;

        if (lp8788_is_valid_charger_register(param->addr)) {
            ret = lp8788_write_byte(lp, param->addr, param->val);
            if (ret)
                return ret;
        }
    }

    return 0;
}

static int lp8788_psy_register(struct platform_device *pdev,
                struct lp8788_charger *pchg)
{
    pchg->charger.name = LP8788_CHARGER_NAME;
    pchg->charger.type = POWER_SUPPLY_TYPE_MAINS;
    pchg->charger.properties = lp8788_charger_prop;
    pchg->charger.num_properties = ARRAY_SIZE(lp8788_charger_prop);
    pchg->charger.get_property = lp8788_charger_get_property;
    pchg->charger.supplied_to = battery_supplied_to;
    pchg->charger.num_supplicants = ARRAY_SIZE(battery_supplied_to);

    if (power_supply_register(&pdev->dev, &pchg->charger))
        return -EPERM;

    pchg->battery.name = LP8788_BATTERY_NAME;
    pchg->battery.type = POWER_SUPPLY_TYPE_BATTERY;
    pchg->battery.properties = lp8788_battery_prop;
    pchg->battery.num_properties = ARRAY_SIZE(lp8788_battery_prop);
    pchg->battery.get_property = lp8788_battery_get_property;

    if (power_supply_register(&pdev->dev, &pchg->battery))
        return -EPERM;

    return 0;
}

static void lp8788_psy_unregister(struct lp8788_charger *pchg)
{
    power_supply_unregister(&pchg->battery);
    power_supply_unregister(&pchg->charger);
}

static void lp8788_charger_event(struct work_struct *work)
{
    struct lp8788_charger *pchg =
        container_of(work, struct lp8788_charger, charger_work);
    struct lp8788_charger_platform_data *pdata = pchg->pdata;
    enum lp8788_charger_event event = lp8788_is_charger_detected(pchg);

    pdata->charger_event(pchg->lp, event);
}

static bool lp8788_find_irq_id(struct lp8788_charger *pchg, int virq, int *id)
{
    bool found;
    int i;

    for (i = 0; i < pchg->num_irqs; i++) {
        if (pchg->irqs[i].virq == virq) {
            *id = pchg->irqs[i].which;
            found = true;
            break;
        }
    }

    return found;
}

static irqreturn_t lp8788_charger_irq_thread(int virq, void *ptr)
{
    struct lp8788_charger *pchg = ptr;
    struct lp8788_charger_platform_data *pdata = pchg->pdata;
    int id = -1;

    if (!lp8788_find_irq_id(pchg, virq, &id))
        return IRQ_NONE;

    switch (id) {
    case LP8788_INT_CHG_INPUT_STATE:
    case LP8788_INT_CHG_STATE:
    case LP8788_INT_EOC:
    case LP8788_INT_BATT_LOW:
    case LP8788_INT_NO_BATT:
        power_supply_changed(&pchg->charger);
        power_supply_changed(&pchg->battery);
        break;
    default:
        break;
    }

    /* report charger dectection event if used */
    if (!pdata)
        goto irq_handled;

    if (pdata->charger_event && id == LP8788_INT_CHG_INPUT_STATE)
        schedule_work(&pchg->charger_work);

irq_handled:
    return IRQ_HANDLED;
}

static int lp8788_set_irqs(struct platform_device *pdev,
            struct lp8788_charger *pchg, const char *name)
{
    struct resource *r;
    struct irq_domain *irqdm = pchg->lp->irqdm;
    int irq_start;
    int irq_end;
    int virq;
    int nr_irq;
    int i;
    int ret;

    /* no error even if no irq resource */
    r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, name);
    if (!r)
        return 0;

    irq_start = r->start;
    irq_end = r->end;

    for (i = irq_start; i <= irq_end; i++) {
        nr_irq = pchg->num_irqs;

        virq = irq_create_mapping(irqdm, i);
        pchg->irqs[nr_irq].virq = virq;
        pchg->irqs[nr_irq].which = i;
        pchg->num_irqs++;

        ret = request_threaded_irq(virq, NULL,
                    lp8788_charger_irq_thread,
                    0, name, pchg);
        if (ret)
            break;
    }

    if (i <= irq_end)
        goto err_free_irq;

    return 0;

err_free_irq:
    for (i = 0; i < pchg->num_irqs; i++)
        free_irq(pchg->irqs[i].virq, pchg);
    return ret;
}

static int lp8788_irq_register(struct platform_device *pdev,
                struct lp8788_charger *pchg)
{
    struct lp8788 *lp = pchg->lp;
    const char *name[] = {
        LP8788_CHG_IRQ, LP8788_PRSW_IRQ, LP8788_BATT_IRQ
    };
    int i;
    int ret;

    INIT_WORK(&pchg->charger_work, lp8788_charger_event);
    pchg->num_irqs = 0;

    for (i = 0; i < ARRAY_SIZE(name); i++) {
        ret = lp8788_set_irqs(pdev, pchg, name[i]);
        if (ret) {
            dev_warn(lp->dev, "irq setup failed: %s\n", name[i]);
            return ret;
        }
    }

    if (pchg->num_irqs > LP8788_MAX_CHG_IRQS) {
        dev_err(lp->dev, "invalid total number of irqs: %d\n",
            pchg->num_irqs);
        return -EINVAL;
    }


    return 0;
}

static void lp8788_irq_unregister(struct platform_device *pdev,
                  struct lp8788_charger *pchg)
{
    int i;
    int irq;

    for (i = 0; i < pchg->num_irqs; i++) {
        irq = pchg->irqs[i].virq;
        if (!irq)
            continue;

        free_irq(irq, pchg);
    }
}

static void lp8788_setup_adc_channel(struct lp8788_charger *pchg)
{
    struct lp8788_charger_platform_data *pdata = pchg->pdata;
    struct device *dev = pchg->lp->dev;
    struct iio_channel *chan;
    enum lp8788_adc_id id;
    const char *chan_name[LPADC_MAX] = {
        [LPADC_VBATT_5P5] = "vbatt-5p5",
        [LPADC_VBATT_6P0] = "vbatt-6p0",
        [LPADC_VBATT_5P0] = "vbatt-5p0",
        [LPADC_ADC1]      = "adc1",
        [LPADC_ADC2]      = "adc2",
        [LPADC_ADC3]      = "adc3",
        [LPADC_ADC4]      = "adc4",
    };

    if (!pdata)
        return;

    id = pdata->vbatt_adc;
    switch (id) {
    case LPADC_VBATT_5P5:
    case LPADC_VBATT_6P0:
    case LPADC_VBATT_5P0:
        chan = iio_channel_get(NULL, chan_name[id]);
        pchg->chan[LP8788_VBATT] = IS_ERR(chan) ? NULL : chan;
        break;
    default:
        dev_err(dev, "invalid ADC id for VBATT: %d\n", id);
        pchg->chan[LP8788_VBATT] = NULL;
        break;
    }

    id = pdata->batt_temp_adc;
    switch (id) {
    case LPADC_ADC1:
    case LPADC_ADC2:
    case LPADC_ADC3:
    case LPADC_ADC4:
        chan = iio_channel_get(NULL, chan_name[id]);
        pchg->chan[LP8788_BATT_TEMP] = IS_ERR(chan) ? NULL : chan;
        break;
    default:
        dev_err(dev, "invalid ADC id for BATT_TEMP : %d\n", id);
        pchg->chan[LP8788_BATT_TEMP] = NULL;
        break;
    }
}

static void lp8788_release_adc_channel(struct lp8788_charger *pchg)
{
    int i;

    for (i = 0; i < LP8788_NUM_CHG_ADC; i++) {
        if (!pchg->chan[i])
            continue;

        iio_channel_release(pchg->chan[i]);
        pchg->chan[i] = NULL;
    }
}

static ssize_t lp8788_show_charger_status(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct lp8788_charger *pchg = dev_get_drvdata(dev);
    enum lp8788_charging_state state;
    char *desc[LP8788_MAX_CHG_STATE] = {
        [LP8788_OFF] = "CHARGER OFF",
        [LP8788_WARM_UP] = "WARM UP",
        [LP8788_LOW_INPUT] = "LOW INPUT STATE",
        [LP8788_PRECHARGE] = "CHARGING - PRECHARGE",
        [LP8788_CC] = "CHARGING - CC",
        [LP8788_CV] = "CHARGING - CV",
        [LP8788_MAINTENANCE] = "NO CHARGING - MAINTENANCE",
        [LP8788_BATTERY_FAULT] = "BATTERY FAULT",
        [LP8788_SYSTEM_SUPPORT] = "SYSTEM SUPPORT",
        [LP8788_HIGH_CURRENT] = "HIGH CURRENT",
    };
    u8 data;

    lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
    state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;

    return scnprintf(buf, LP8788_BUF_SIZE, "%s\n", desc[state]);
}

static ssize_t lp8788_show_eoc_time(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct lp8788_charger *pchg = dev_get_drvdata(dev);
    char *stime[] = { "400ms", "5min", "10min", "15min",
            "20min", "25min", "30min" "No timeout" };
    u8 val;

    lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val);
    val = (val & LP8788_CHG_EOC_TIME_M) >> LP8788_CHG_EOC_TIME_S;

    return scnprintf(buf, LP8788_BUF_SIZE, "End Of Charge Time: %s\n",
            stime[val]);
}

static ssize_t lp8788_show_eoc_level(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct lp8788_charger *pchg = dev_get_drvdata(dev);
    char *abs_level[] = { "25mA", "49mA", "75mA", "98mA" };
    char *relative_level[] = { "5%", "10%", "15%", "20%" };
    char *level;
    u8 val;
    u8 mode;

    lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val);

    mode = val & LP8788_CHG_EOC_MODE_M;
    val = (val & LP8788_CHG_EOC_LEVEL_M) >> LP8788_CHG_EOC_LEVEL_S;
    level = mode ? abs_level[val] : relative_level[val];

    return scnprintf(buf, LP8788_BUF_SIZE, "End Of Charge Level: %s\n",
            level);
}

static DEVICE_ATTR(charger_status, S_IRUSR, lp8788_show_charger_status, NULL);
static DEVICE_ATTR(eoc_time, S_IRUSR, lp8788_show_eoc_time, NULL);
static DEVICE_ATTR(eoc_level, S_IRUSR, lp8788_show_eoc_level, NULL);

static struct attribute *lp8788_charger_attr[] = {
    &dev_attr_charger_status.attr,
    &dev_attr_eoc_time.attr,
    &dev_attr_eoc_level.attr,
    NULL,
};

static const struct attribute_group lp8788_attr_group = {
    .attrs = lp8788_charger_attr,
};

static __devinit int lp8788_charger_probe(struct platform_device *pdev)
{
    struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
    struct lp8788_charger *pchg;
    int ret;

    pchg = devm_kzalloc(lp->dev, sizeof(struct lp8788_charger), GFP_KERNEL);
    if (!pchg)
        return -ENOMEM;

    pchg->lp = lp;
    pchg->pdata = lp->pdata ? lp->pdata->chg_pdata : NULL;
    platform_set_drvdata(pdev, pchg);

    ret = lp8788_update_charger_params(pchg);
    if (ret)
        return ret;

    lp8788_setup_adc_channel(pchg);

    ret = lp8788_psy_register(pdev, pchg);
    if (ret)
        return ret;

    ret = sysfs_create_group(&pdev->dev.kobj, &lp8788_attr_group);
    if (ret) {
        lp8788_psy_unregister(pchg);
        return ret;
    }

    ret = lp8788_irq_register(pdev, pchg);
    if (ret)
        dev_warn(lp->dev, "failed to register charger irq: %d\n", ret);

    return 0;
}

static int __devexit lp8788_charger_remove(struct platform_device *pdev)
{
    struct lp8788_charger *pchg = platform_get_drvdata(pdev);

    flush_work(&pchg->charger_work);
    lp8788_irq_unregister(pdev, pchg);
    sysfs_remove_group(&pdev->dev.kobj, &lp8788_attr_group);
    lp8788_psy_unregister(pchg);
    lp8788_release_adc_channel(pchg);

    return 0;
}

static struct platform_driver lp8788_charger_driver = {
    .probe = lp8788_charger_probe,
    .remove = __devexit_p(lp8788_charger_remove),
    .driver = {
        .name = LP8788_DEV_CHARGER,
        .owner = THIS_MODULE,
    },
};
module_platform_driver(lp8788_charger_driver);

MODULE_DESCRIPTION("TI LP8788 Charger Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lp8788-charger");