// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * GPIO Driver for Dialog DA9055 PMICs.
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: David Dajun Chen <dchen@diasemi.com>
 */
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/gpio/driver.h>

#include <linux/mfd/da9055/core.h>
#include <linux/mfd/da9055/reg.h>
#include <linux/mfd/da9055/pdata.h>

#define DA9055_VDD_IO                   0x0
#define DA9055_PUSH_PULL                0x3
#define DA9055_ACT_LOW                  0x0
#define DA9055_GPI                      0x1
#define DA9055_PORT_MASK                0x3
#define DA9055_PORT_SHIFT(offset)       (4 * (offset % 2))

#define DA9055_INPUT                    DA9055_GPI
#define DA9055_OUTPUT                   DA9055_PUSH_PULL
#define DA9055_IRQ_GPI0                 3

struct da9055_gpio {
        struct da9055 *da9055;
        struct gpio_chip gp;
};

static int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
{
        struct da9055_gpio *gpio = gpiochip_get_data(gc);
        int gpio_direction = 0;
        int ret;

        /* Get GPIO direction */
        ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
        if (ret < 0)
                return ret;

        gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
        gpio_direction >>= DA9055_PORT_SHIFT(offset);
        switch (gpio_direction) {
        case DA9055_INPUT:
                ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
                if (ret < 0)
                        return ret;
                break;
        case DA9055_OUTPUT:
                ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
                if (ret < 0)
                        return ret;
        }

        return !!(ret & (1 << offset));

}

static int da9055_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
{
        struct da9055_gpio *gpio = gpiochip_get_data(gc);

        return da9055_reg_update(gpio->da9055, DA9055_REG_GPIO_MODE0_2,
                                 1 << offset, value << offset);
}

static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
        struct da9055_gpio *gpio = gpiochip_get_data(gc);
        unsigned char reg_byte;

        reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
                                << DA9055_PORT_SHIFT(offset);

        return da9055_reg_update(gpio->da9055, (offset >> 1) +
                                DA9055_REG_GPIO0_1,
                                DA9055_PORT_MASK <<
                                DA9055_PORT_SHIFT(offset),
                                reg_byte);
}

static int da9055_gpio_direction_output(struct gpio_chip *gc,
                                        unsigned offset, int value)
{
        struct da9055_gpio *gpio = gpiochip_get_data(gc);
        unsigned char reg_byte;
        int ret;

        reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
                                        << DA9055_PORT_SHIFT(offset);

        ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
                                DA9055_REG_GPIO0_1,
                                DA9055_PORT_MASK <<
                                DA9055_PORT_SHIFT(offset),
                                reg_byte);
        if (ret < 0)
                return ret;

        return da9055_gpio_set(gc, offset, value);
}

static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
{
        struct da9055_gpio *gpio = gpiochip_get_data(gc);
        struct da9055 *da9055 = gpio->da9055;

        return regmap_irq_get_virq(da9055->irq_data,
                                  DA9055_IRQ_GPI0 + offset);
}

static const struct gpio_chip reference_gp = {
        .label = "da9055-gpio",
        .owner = THIS_MODULE,
        .get = da9055_gpio_get,
        .set = da9055_gpio_set,
        .direction_input = da9055_gpio_direction_input,
        .direction_output = da9055_gpio_direction_output,
        .to_irq = da9055_gpio_to_irq,
        .can_sleep = true,
        .ngpio = 3,
        .base = -1,
};

static int da9055_gpio_probe(struct platform_device *pdev)
{
        struct da9055_gpio *gpio;
        struct da9055_pdata *pdata;

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

        gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
        pdata = dev_get_platdata(gpio->da9055->dev);

        gpio->gp = reference_gp;
        if (pdata && pdata->gpio_base)
                gpio->gp.base = pdata->gpio_base;

        return devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
}

static struct platform_driver da9055_gpio_driver = {
        .probe = da9055_gpio_probe,
        .driver = {
                .name   = "da9055-gpio",
        },
};

static int __init da9055_gpio_init(void)
{
        return platform_driver_register(&da9055_gpio_driver);
}
subsys_initcall(da9055_gpio_init);

static void __exit da9055_gpio_exit(void)
{
        platform_driver_unregister(&da9055_gpio_driver);
}
module_exit(da9055_gpio_exit);

MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:da9055-gpio");