// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Backlight Driver for Dialog DA9052 PMICs
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: David Dajun Chen <dchen@diasemi.com>
 */

#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>

#include <linux/mfd/da9052/da9052.h>
#include <linux/mfd/da9052/reg.h>

#define DA9052_MAX_BRIGHTNESS           0xFF

enum {
        DA9052_WLEDS_OFF,
        DA9052_WLEDS_ON,
};

enum {
        DA9052_TYPE_WLED1,
        DA9052_TYPE_WLED2,
        DA9052_TYPE_WLED3,
};

static const unsigned char wled_bank[] = {
        DA9052_LED1_CONF_REG,
        DA9052_LED2_CONF_REG,
        DA9052_LED3_CONF_REG,
};

struct da9052_bl {
        struct da9052 *da9052;
        uint brightness;
        uint state;
        uint led_reg;
};

static int da9052_adjust_wled_brightness(struct da9052_bl *wleds)
{
        unsigned char boost_en;
        unsigned char i_sink;
        int ret;

        boost_en = 0x3F;
        i_sink = 0xFF;
        if (wleds->state == DA9052_WLEDS_OFF) {
                boost_en = 0x00;
                i_sink = 0x00;
        }

        ret = da9052_reg_write(wleds->da9052, DA9052_BOOST_REG, boost_en);
        if (ret < 0)
                return ret;

        ret = da9052_reg_write(wleds->da9052, DA9052_LED_CONT_REG, i_sink);
        if (ret < 0)
                return ret;

        ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 0x0);
        if (ret < 0)
                return ret;

        usleep_range(10000, 11000);

        if (wleds->brightness) {
                ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg],
                                       wleds->brightness);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static int da9052_backlight_update_status(struct backlight_device *bl)
{
        int brightness = bl->props.brightness;
        struct da9052_bl *wleds = bl_get_data(bl);

        wleds->brightness = brightness;
        wleds->state = DA9052_WLEDS_ON;

        return da9052_adjust_wled_brightness(wleds);
}

static int da9052_backlight_get_brightness(struct backlight_device *bl)
{
        struct da9052_bl *wleds = bl_get_data(bl);

        return wleds->brightness;
}

static const struct backlight_ops da9052_backlight_ops = {
        .update_status = da9052_backlight_update_status,
        .get_brightness = da9052_backlight_get_brightness,
};

static int da9052_backlight_probe(struct platform_device *pdev)
{
        struct backlight_device *bl;
        struct backlight_properties props;
        struct da9052_bl *wleds;

        wleds = devm_kzalloc(&pdev->dev, sizeof(struct da9052_bl), GFP_KERNEL);
        if (!wleds)
                return -ENOMEM;

        wleds->da9052 = dev_get_drvdata(pdev->dev.parent);
        wleds->brightness = 0;
        wleds->led_reg = platform_get_device_id(pdev)->driver_data;
        wleds->state = DA9052_WLEDS_OFF;

        memset(&props, 0, sizeof(struct backlight_properties));
        props.type = BACKLIGHT_RAW;
        props.max_brightness = DA9052_MAX_BRIGHTNESS;

        bl = devm_backlight_device_register(&pdev->dev, pdev->name,
                                        wleds->da9052->dev, wleds,
                                        &da9052_backlight_ops, &props);
        if (IS_ERR(bl)) {
                dev_err(&pdev->dev, "Failed to register backlight\n");
                return PTR_ERR(bl);
        }

        bl->props.max_brightness = DA9052_MAX_BRIGHTNESS;
        bl->props.brightness = 0;
        platform_set_drvdata(pdev, bl);

        return da9052_adjust_wled_brightness(wleds);
}

static void da9052_backlight_remove(struct platform_device *pdev)
{
        struct backlight_device *bl = platform_get_drvdata(pdev);
        struct da9052_bl *wleds = bl_get_data(bl);

        wleds->brightness = 0;
        wleds->state = DA9052_WLEDS_OFF;
        da9052_adjust_wled_brightness(wleds);
}

static const struct platform_device_id da9052_wled_ids[] = {
        {
                .name           = "da9052-wled1",
                .driver_data    = DA9052_TYPE_WLED1,
        },
        {
                .name           = "da9052-wled2",
                .driver_data    = DA9052_TYPE_WLED2,
        },
        {
                .name           = "da9052-wled3",
                .driver_data    = DA9052_TYPE_WLED3,
        },
        { },
};
MODULE_DEVICE_TABLE(platform, da9052_wled_ids);

static struct platform_driver da9052_wled_driver = {
        .probe          = da9052_backlight_probe,
        .remove         = da9052_backlight_remove,
        .id_table       = da9052_wled_ids,
        .driver = {
                .name   = "da9052-wled",
        },
};

module_platform_driver(da9052_wled_driver);

MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC");
MODULE_LICENSE("GPL");