// SPDX-License-Identifier: GPL-2.0-only
/*
 * I2C driver for Marvell 88PM80x
 *
 * Copyright (C) 2012 Marvell International Ltd.
 * Haojian Zhuang <haojian.zhuang@marvell.com>
 * Joseph(Yossi) Hanin <yhanin@marvell.com>
 * Qiao Zhou <zhouqiao@marvell.com>
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/mfd/88pm80x.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/err.h>

/* 88pm80x chips have same definition for chip id register. */
#define PM80X_CHIP_ID                   (0x00)
#define PM80X_CHIP_ID_NUM(x)            (((x) >> 5) & 0x7)
#define PM80X_CHIP_ID_REVISION(x)       ((x) & 0x1F)

struct pm80x_chip_mapping {
        unsigned int    id;
        int             type;
};

static struct pm80x_chip_mapping chip_mapping[] = {
        /* 88PM800 chip id number */
        {0x3,   CHIP_PM800},
        /* 88PM805 chip id number */
        {0x0,   CHIP_PM805},
        /* 88PM860 chip id number */
        {0x4,   CHIP_PM860},
};

/*
 * workaround: some registers needed by pm805 are defined in pm800, so
 * need to use this global variable to maintain the relation between
 * pm800 and pm805. would remove it after HW chip fixes the issue.
 */
static struct pm80x_chip *g_pm80x_chip;

const struct regmap_config pm80x_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,
};
EXPORT_SYMBOL_GPL(pm80x_regmap_config);


int pm80x_init(struct i2c_client *client)
{
        struct pm80x_chip *chip;
        struct regmap *map;
        unsigned int val;
        int i, ret = 0;

        chip =
            devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
        if (!chip)
                return -ENOMEM;

        map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
        if (IS_ERR(map)) {
                ret = PTR_ERR(map);
                dev_err(&client->dev, "Failed to allocate register map: %d\n",
                        ret);
                return ret;
        }

        chip->client = client;
        chip->regmap = map;

        chip->irq = client->irq;

        chip->dev = &client->dev;
        i2c_set_clientdata(chip->client, chip);

        ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
        if (ret < 0) {
                dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
                return ret;
        }

        for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
                if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
                        chip->type = chip_mapping[i].type;
                        break;
                }
        }

        if (i == ARRAY_SIZE(chip_mapping)) {
                dev_err(chip->dev,
                        "Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
                return -EINVAL;
        }

        device_init_wakeup(&client->dev, 1);

        /*
         * workaround: set g_pm80x_chip to the first probed chip. if the
         * second chip is probed, just point to the companion to each
         * other so that pm805 can access those specific register. would
         * remove it after HW chip fixes the issue.
         */
        if (!g_pm80x_chip)
                g_pm80x_chip = chip;
        else {
                chip->companion = g_pm80x_chip->client;
                g_pm80x_chip->companion = chip->client;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(pm80x_init);

int pm80x_deinit(void)
{
        /*
         * workaround: clear the dependency between pm800 and pm805.
         * would remove it after HW chip fixes the issue.
         */
        if (g_pm80x_chip->companion)
                g_pm80x_chip->companion = NULL;
        else
                g_pm80x_chip = NULL;
        return 0;
}
EXPORT_SYMBOL_GPL(pm80x_deinit);

static int pm80x_suspend(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct pm80x_chip *chip = i2c_get_clientdata(client);

        if (chip && chip->wu_flag)
                if (device_may_wakeup(chip->dev))
                        enable_irq_wake(chip->irq);

        return 0;
}

static int pm80x_resume(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct pm80x_chip *chip = i2c_get_clientdata(client);

        if (chip && chip->wu_flag)
                if (device_may_wakeup(chip->dev))
                        disable_irq_wake(chip->irq);

        return 0;
}

EXPORT_GPL_SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);

MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
MODULE_LICENSE("GPL");