// SPDX-License-Identifier: GPL-2.0-only
/*
 * TI LP8788 MFD - keyled driver
 *
 * Copyright 2012 Texas Instruments
 *
 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/mutex.h>
#include <linux/mfd/lp8788.h>
#include <linux/mfd/lp8788-isink.h>

#define MAX_BRIGHTNESS                  LP8788_ISINK_MAX_PWM
#define DEFAULT_LED_NAME                "keyboard-backlight"

struct lp8788_led {
        struct lp8788 *lp;
        struct mutex lock;
        struct led_classdev led_dev;
        enum lp8788_isink_number isink_num;
        int on;
};

struct lp8788_led_config {
        enum lp8788_isink_scale scale;
        enum lp8788_isink_number num;
        int iout;
};

static struct lp8788_led_config default_led_config = {
        .scale = LP8788_ISINK_SCALE_100mA,
        .num   = LP8788_ISINK_3,
        .iout  = 0,
};

static int lp8788_led_init_device(struct lp8788_led *led,
                                struct lp8788_led_platform_data *pdata)
{
        struct lp8788_led_config *cfg = &default_led_config;
        u8 addr, mask, val;
        int ret;

        if (pdata) {
                cfg->scale = pdata->scale;
                cfg->num = pdata->num;
                cfg->iout = pdata->iout_code;
        }

        led->isink_num = cfg->num;

        /* scale configuration */
        addr = LP8788_ISINK_CTRL;
        mask = 1 << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
        val = cfg->scale << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
        ret = lp8788_update_bits(led->lp, addr, mask, val);
        if (ret)
                return ret;

        /* current configuration */
        addr = lp8788_iout_addr[cfg->num];
        mask = lp8788_iout_mask[cfg->num];
        val = cfg->iout;

        return lp8788_update_bits(led->lp, addr, mask, val);
}

static int lp8788_led_enable(struct lp8788_led *led,
                        enum lp8788_isink_number num, int on)
{
        int ret;

        u8 mask = 1 << num;
        u8 val = on << num;

        ret = lp8788_update_bits(led->lp, LP8788_ISINK_CTRL, mask, val);
        if (ret == 0)
                led->on = on;

        return ret;
}

static int lp8788_brightness_set(struct led_classdev *led_cdev,
                                enum led_brightness val)
{
        struct lp8788_led *led =
                        container_of(led_cdev, struct lp8788_led, led_dev);

        enum lp8788_isink_number num = led->isink_num;
        int enable, ret;

        mutex_lock(&led->lock);

        switch (num) {
        case LP8788_ISINK_1:
        case LP8788_ISINK_2:
        case LP8788_ISINK_3:
                ret = lp8788_write_byte(led->lp, lp8788_pwm_addr[num], val);
                if (ret < 0)
                        goto unlock;
                break;
        default:
                mutex_unlock(&led->lock);
                return -EINVAL;
        }

        enable = (val > 0) ? 1 : 0;
        if (enable != led->on)
                ret = lp8788_led_enable(led, num, enable);
unlock:
        mutex_unlock(&led->lock);
        return ret;
}

static int lp8788_led_probe(struct platform_device *pdev)
{
        struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
        struct lp8788_led_platform_data *led_pdata;
        struct lp8788_led *led;
        struct device *dev = &pdev->dev;
        int ret;

        led = devm_kzalloc(dev, sizeof(struct lp8788_led), GFP_KERNEL);
        if (!led)
                return -ENOMEM;

        led->lp = lp;
        led->led_dev.max_brightness = MAX_BRIGHTNESS;
        led->led_dev.brightness_set_blocking = lp8788_brightness_set;

        led_pdata = lp->pdata ? lp->pdata->led_pdata : NULL;

        if (!led_pdata || !led_pdata->name)
                led->led_dev.name = DEFAULT_LED_NAME;
        else
                led->led_dev.name = led_pdata->name;

        mutex_init(&led->lock);

        ret = lp8788_led_init_device(led, led_pdata);
        if (ret) {
                dev_err(dev, "led init device err: %d\n", ret);
                return ret;
        }

        ret = devm_led_classdev_register(dev, &led->led_dev);
        if (ret) {
                dev_err(dev, "led register err: %d\n", ret);
                return ret;
        }

        return 0;
}

static struct platform_driver lp8788_led_driver = {
        .probe = lp8788_led_probe,
        .driver = {
                .name = LP8788_DEV_KEYLED,
        },
};
module_platform_driver(lp8788_led_driver);

MODULE_DESCRIPTION("Texas Instruments LP8788 Keyboard LED Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lp8788-keyled");