// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
 *      Keerthy <j-keerthy@ti.com>
 *
 * Based on the LP873X driver
 */

#include <linux/gpio/driver.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#include <linux/mfd/lp87565.h>

struct lp87565_gpio {
        struct gpio_chip chip;
        struct regmap *map;
};

static int lp87565_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(chip);
        int ret, val;

        ret = regmap_read(gpio->map, LP87565_REG_GPIO_IN, &val);
        if (ret < 0)
                return ret;

        return !!(val & BIT(offset));
}

static int lp87565_gpio_set(struct gpio_chip *chip, unsigned int offset,
                            int value)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(chip);

        return regmap_update_bits(gpio->map, LP87565_REG_GPIO_OUT,
                                  BIT(offset), value ? BIT(offset) : 0);
}

static int lp87565_gpio_get_direction(struct gpio_chip *chip,
                                      unsigned int offset)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(chip);
        int ret, val;

        ret = regmap_read(gpio->map, LP87565_REG_GPIO_CONFIG, &val);
        if (ret < 0)
                return ret;

        if (val & BIT(offset))
                return GPIO_LINE_DIRECTION_OUT;

        return GPIO_LINE_DIRECTION_IN;
}

static int lp87565_gpio_direction_input(struct gpio_chip *chip,
                                        unsigned int offset)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(chip);

        return regmap_update_bits(gpio->map,
                                  LP87565_REG_GPIO_CONFIG,
                                  BIT(offset), 0);
}

static int lp87565_gpio_direction_output(struct gpio_chip *chip,
                                         unsigned int offset, int value)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(chip);
        int ret;

        ret = lp87565_gpio_set(chip, offset, value);
        if (ret)
                return ret;

        return regmap_update_bits(gpio->map,
                                  LP87565_REG_GPIO_CONFIG,
                                  BIT(offset), BIT(offset));
}

static int lp87565_gpio_request(struct gpio_chip *gc, unsigned int offset)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(gc);
        int ret;

        switch (offset) {
        case 0:
        case 1:
        case 2:
                /*
                 * MUX can program the pin to be in EN1/2/3 pin mode
                 * Or GPIO1/2/3 mode.
                 * Setup the GPIO*_SEL MUX to GPIO mode
                 */
                ret = regmap_update_bits(gpio->map,
                                         LP87565_REG_PIN_FUNCTION,
                                         BIT(offset), BIT(offset));
                if (ret)
                        return ret;

                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int lp87565_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
                                   unsigned long config)
{
        struct lp87565_gpio *gpio = gpiochip_get_data(gc);

        switch (pinconf_to_config_param(config)) {
        case PIN_CONFIG_DRIVE_OPEN_DRAIN:
                return regmap_update_bits(gpio->map,
                                          LP87565_REG_GPIO_CONFIG,
                                          BIT(offset +
                                              __ffs(LP87565_GPIO1_OD)),
                                          BIT(offset +
                                              __ffs(LP87565_GPIO1_OD)));
        case PIN_CONFIG_DRIVE_PUSH_PULL:
                return regmap_update_bits(gpio->map,
                                          LP87565_REG_GPIO_CONFIG,
                                          BIT(offset +
                                              __ffs(LP87565_GPIO1_OD)), 0);
        default:
                return -ENOTSUPP;
        }
}

static const struct gpio_chip template_chip = {
        .label                  = "lp87565-gpio",
        .owner                  = THIS_MODULE,
        .request                = lp87565_gpio_request,
        .get_direction          = lp87565_gpio_get_direction,
        .direction_input        = lp87565_gpio_direction_input,
        .direction_output       = lp87565_gpio_direction_output,
        .get                    = lp87565_gpio_get,
        .set                    = lp87565_gpio_set,
        .set_config             = lp87565_gpio_set_config,
        .base                   = -1,
        .ngpio                  = 3,
        .can_sleep              = true,
};

static int lp87565_gpio_probe(struct platform_device *pdev)
{
        struct lp87565_gpio *gpio;
        struct lp87565 *lp87565;
        int ret;

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

        lp87565 = dev_get_drvdata(pdev->dev.parent);
        gpio->chip = template_chip;
        gpio->chip.parent = lp87565->dev;
        gpio->map = lp87565->regmap;

        ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
        if (ret < 0) {
                dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
                return ret;
        }

        return 0;
}

static const struct platform_device_id lp87565_gpio_id_table[] = {
        { "lp87565-q1-gpio", },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, lp87565_gpio_id_table);

static struct platform_driver lp87565_gpio_driver = {
        .driver = {
                .name = "lp87565-gpio",
        },
        .probe = lp87565_gpio_probe,
        .id_table = lp87565_gpio_id_table,
};
module_platform_driver(lp87565_gpio_driver);

MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>");
MODULE_DESCRIPTION("LP87565 GPIO driver");
MODULE_LICENSE("GPL v2");