/*
 * tps65217.c
 *
 * TPS65217 chip family multi-function driver
 *
 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.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 version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; 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/device.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/regmap.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <linux/mfd/core.h>
#include <linux/mfd/tps65217.h>

static const struct mfd_cell tps65217s[] = {
        {
                .name = "tps65217-pmic",
                .of_compatible = "ti,tps65217-pmic",
        },
        {
                .name = "tps65217-bl",
                .of_compatible = "ti,tps65217-bl",
        },
};

/**
 * tps65217_reg_read: Read a single tps65217 register.
 *
 * @tps: Device to read from.
 * @reg: Register to read.
 * @val: Contians the value
 */
int tps65217_reg_read(struct tps65217 *tps, unsigned int reg,
                        unsigned int *val)
{
        return regmap_read(tps->regmap, reg, val);
}
EXPORT_SYMBOL_GPL(tps65217_reg_read);

/**
 * tps65217_reg_write: Write a single tps65217 register.
 *
 * @tps65217: Device to write to.
 * @reg: Register to write to.
 * @val: Value to write.
 * @level: Password protected level
 */
int tps65217_reg_write(struct tps65217 *tps, unsigned int reg,
                        unsigned int val, unsigned int level)
{
        int ret;
        unsigned int xor_reg_val;

        switch (level) {
        case TPS65217_PROTECT_NONE:
                return regmap_write(tps->regmap, reg, val);
        case TPS65217_PROTECT_L1:
                xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
                ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
                                                        xor_reg_val);
                if (ret < 0)
                        return ret;

                return regmap_write(tps->regmap, reg, val);
        case TPS65217_PROTECT_L2:
                xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
                ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
                                                        xor_reg_val);
                if (ret < 0)
                        return ret;
                ret = regmap_write(tps->regmap, reg, val);
                if (ret < 0)
                        return ret;
                ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
                                                        xor_reg_val);
                if (ret < 0)
                        return ret;
                return regmap_write(tps->regmap, reg, val);
        default:
                return -EINVAL;
        }
}
EXPORT_SYMBOL_GPL(tps65217_reg_write);

/**
 * tps65217_update_bits: Modify bits w.r.t mask, val and level.
 *
 * @tps65217: Device to write to.
 * @reg: Register to read-write to.
 * @mask: Mask.
 * @val: Value to write.
 * @level: Password protected level
 */
static int tps65217_update_bits(struct tps65217 *tps, unsigned int reg,
                unsigned int mask, unsigned int val, unsigned int level)
{
        int ret;
        unsigned int data;

        ret = tps65217_reg_read(tps, reg, &data);
        if (ret) {
                dev_err(tps->dev, "Read from reg 0x%x failed\n", reg);
                return ret;
        }

        data &= ~mask;
        data |= val & mask;

        ret = tps65217_reg_write(tps, reg, data, level);
        if (ret)
                dev_err(tps->dev, "Write for reg 0x%x failed\n", reg);

        return ret;
}

int tps65217_set_bits(struct tps65217 *tps, unsigned int reg,
                unsigned int mask, unsigned int val, unsigned int level)
{
        return tps65217_update_bits(tps, reg, mask, val, level);
}
EXPORT_SYMBOL_GPL(tps65217_set_bits);

int tps65217_clear_bits(struct tps65217 *tps, unsigned int reg,
                unsigned int mask, unsigned int level)
{
        return tps65217_update_bits(tps, reg, mask, 0, level);
}
EXPORT_SYMBOL_GPL(tps65217_clear_bits);

static const struct regmap_config tps65217_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,

        .max_register = TPS65217_REG_MAX,
};

static const struct of_device_id tps65217_of_match[] = {
        { .compatible = "ti,tps65217", .data = (void *)TPS65217 },
        { /* sentinel */ },
};

static int tps65217_probe(struct i2c_client *client,
                                const struct i2c_device_id *ids)
{
        struct tps65217 *tps;
        unsigned int version;
        unsigned long chip_id = ids->driver_data;
        const struct of_device_id *match;
        bool status_off = false;
        int ret;

        if (client->dev.of_node) {
                match = of_match_device(tps65217_of_match, &client->dev);
                if (!match) {
                        dev_err(&client->dev,
                                "Failed to find matching dt id\n");
                        return -EINVAL;
                }
                chip_id = (unsigned long)match->data;
                status_off = of_property_read_bool(client->dev.of_node,
                                        "ti,pmic-shutdown-controller");
        }

        if (!chip_id) {
                dev_err(&client->dev, "id is null.\n");
                return -ENODEV;
        }

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

        i2c_set_clientdata(client, tps);
        tps->dev = &client->dev;
        tps->id = chip_id;

        tps->regmap = devm_regmap_init_i2c(client, &tps65217_regmap_config);
        if (IS_ERR(tps->regmap)) {
                ret = PTR_ERR(tps->regmap);
                dev_err(tps->dev, "Failed to allocate register map: %d\n",
                        ret);
                return ret;
        }

        ret = mfd_add_devices(tps->dev, -1, tps65217s,
                              ARRAY_SIZE(tps65217s), NULL, 0, NULL);
        if (ret < 0) {
                dev_err(tps->dev, "mfd_add_devices failed: %d\n", ret);
                return ret;
        }

        ret = tps65217_reg_read(tps, TPS65217_REG_CHIPID, &version);
        if (ret < 0) {
                dev_err(tps->dev, "Failed to read revision register: %d\n",
                        ret);
                return ret;
        }

        /* Set the PMIC to shutdown on PWR_EN toggle */
        if (status_off) {
                ret = tps65217_set_bits(tps, TPS65217_REG_STATUS,
                                TPS65217_STATUS_OFF, TPS65217_STATUS_OFF,
                                TPS65217_PROTECT_NONE);
                if (ret)
                        dev_warn(tps->dev, "unable to set the status OFF\n");
        }

        dev_info(tps->dev, "TPS65217 ID %#x version 1.%d\n",
                        (version & TPS65217_CHIPID_CHIP_MASK) >> 4,
                        version & TPS65217_CHIPID_REV_MASK);

        return 0;
}

static int tps65217_remove(struct i2c_client *client)
{
        struct tps65217 *tps = i2c_get_clientdata(client);

        mfd_remove_devices(tps->dev);

        return 0;
}

static const struct i2c_device_id tps65217_id_table[] = {
        {"tps65217", TPS65217},
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, tps65217_id_table);

static struct i2c_driver tps65217_driver = {
        .driver         = {
                .name   = "tps65217",
                .owner  = THIS_MODULE,
                .of_match_table = tps65217_of_match,
        },
        .id_table       = tps65217_id_table,
        .probe          = tps65217_probe,
        .remove         = tps65217_remove,
};

static int __init tps65217_init(void)
{
        return i2c_add_driver(&tps65217_driver);
}
subsys_initcall(tps65217_init);

static void __exit tps65217_exit(void)
{
        i2c_del_driver(&tps65217_driver);
}
module_exit(tps65217_exit);

MODULE_AUTHOR("AnilKumar Ch <anilkumar@ti.com>");
MODULE_DESCRIPTION("TPS65217 chip family multi-function driver");
MODULE_LICENSE("GPL v2");