max8997_charger.c

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/*
 * max8997_charger.c - Power supply consumer driver for the Maxim 8997/8966
 *
 *  Copyright (C) 2011 Samsung Electronics
 *  MyungJoo Ham <[email protected]>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/max8997.h>
#include <linux/mfd/max8997-private.h>

struct charger_data {
    struct device *dev;
    struct max8997_dev *iodev;
    struct power_supply battery;
};

static enum power_supply_property max8997_battery_props[] = {
    POWER_SUPPLY_PROP_STATUS, /* "FULL" or "NOT FULL" only. */
    POWER_SUPPLY_PROP_PRESENT, /* the presence of battery */
    POWER_SUPPLY_PROP_ONLINE, /* charger is active or not */
};

/* Note that the charger control is done by a current regulator "CHARGER" */
static int max8997_battery_get_property(struct power_supply *psy,
        enum power_supply_property psp,
        union power_supply_propval *val)
{
    struct charger_data *charger = container_of(psy,
            struct charger_data, battery);
    struct i2c_client *i2c = charger->iodev->i2c;
    int ret;
    u8 reg;

    switch (psp) {
    case POWER_SUPPLY_PROP_STATUS:
        val->intval = 0;
        ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
        if (ret)
            return ret;
        if ((reg & (1 << 0)) == 0x1)
            val->intval = POWER_SUPPLY_STATUS_FULL;

        break;
    case POWER_SUPPLY_PROP_PRESENT:
        val->intval = 0;
        ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
        if (ret)
            return ret;
        if ((reg & (1 << 2)) == 0x0)
            val->intval = 1;

        break;
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = 0;
        ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
        if (ret)
            return ret;
        /* DCINOK */
        if (reg & (1 << 1))
            val->intval = 1;

        break;
    default:
        return -EINVAL;
    }

    return 0;
}

static __devinit int max8997_battery_probe(struct platform_device *pdev)
{
    int ret = 0;
    struct charger_data *charger;
    struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
    struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);

    if (!pdata)
        return -EINVAL;

    if (pdata->eoc_mA) {
        int val = (pdata->eoc_mA - 50) / 10;
        if (val < 0)
            val = 0;
        if (val > 0xf)
            val = 0xf;

        ret = max8997_update_reg(iodev->i2c,
                MAX8997_REG_MBCCTRL5, val, 0xf);
        if (ret < 0) {
            dev_err(&pdev->dev, "Cannot use i2c bus.\n");
            return ret;
        }
    }

    switch (pdata->timeout) {
    case 5:
        ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
                0x2 << 4, 0x7 << 4);
        break;
    case 6:
        ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
                0x3 << 4, 0x7 << 4);
        break;
    case 7:
        ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
                0x4 << 4, 0x7 << 4);
        break;
    case 0:
        ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
                0x7 << 4, 0x7 << 4);
        break;
    default:
        dev_err(&pdev->dev, "incorrect timeout value (%d)\n",
                pdata->timeout);
        return -EINVAL;
    }
    if (ret < 0) {
        dev_err(&pdev->dev, "Cannot use i2c bus.\n");
        return ret;
    }

    charger = kzalloc(sizeof(struct charger_data), GFP_KERNEL);
    if (charger == NULL) {
        dev_err(&pdev->dev, "Cannot allocate memory.\n");
        return -ENOMEM;
    }

    platform_set_drvdata(pdev, charger);

    charger->battery.name = "max8997_pmic";
    charger->battery.type = POWER_SUPPLY_TYPE_BATTERY;
    charger->battery.get_property = max8997_battery_get_property;
    charger->battery.properties = max8997_battery_props;
    charger->battery.num_properties = ARRAY_SIZE(max8997_battery_props);

    charger->dev = &pdev->dev;
    charger->iodev = iodev;

    ret = power_supply_register(&pdev->dev, &charger->battery);
    if (ret) {
        dev_err(&pdev->dev, "failed: power supply register\n");
        goto err;
    }

    return 0;
err:
    kfree(charger);
    return ret;
}

static int __devexit max8997_battery_remove(struct platform_device *pdev)
{
    struct charger_data *charger = platform_get_drvdata(pdev);

    power_supply_unregister(&charger->battery);
    kfree(charger);
    return 0;
}

static const struct platform_device_id max8997_battery_id[] = {
    { "max8997-battery", 0 },
    { }
};

static struct platform_driver max8997_battery_driver = {
    .driver = {
        .name = "max8997-battery",
        .owner = THIS_MODULE,
    },
    .probe = max8997_battery_probe,
    .remove = __devexit_p(max8997_battery_remove),
    .id_table = max8997_battery_id,
};

static int __init max8997_battery_init(void)
{
    return platform_driver_register(&max8997_battery_driver);
}
subsys_initcall(max8997_battery_init);

static void __exit max8997_battery_cleanup(void)
{
    platform_driver_unregister(&max8997_battery_driver);
}
module_exit(max8997_battery_cleanup);

MODULE_DESCRIPTION("MAXIM 8997/8966 battery control driver");
MODULE_AUTHOR("MyungJoo Ham <[email protected]>");
MODULE_LICENSE("GPL");