// SPDX-License-Identifier: GPL-2.0
//
// Copyright (C) 2018 BayLibre SAS
// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
//
// LED driver for MAXIM 77650/77651 charger/power-supply.

#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/mfd/max77650.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define MAX77650_LED_NUM_LEDS           3

#define MAX77650_LED_A_BASE             0x40
#define MAX77650_LED_B_BASE             0x43

#define MAX77650_LED_BR_MASK            GENMASK(4, 0)
#define MAX77650_LED_EN_MASK            GENMASK(7, 6)

#define MAX77650_LED_MAX_BRIGHTNESS     MAX77650_LED_BR_MASK

/* Enable EN_LED_MSTR. */
#define MAX77650_LED_TOP_DEFAULT        BIT(0)

#define MAX77650_LED_ENABLE             GENMASK(7, 6)
#define MAX77650_LED_DISABLE            0x00

#define MAX77650_LED_A_DEFAULT          MAX77650_LED_DISABLE
/* 100% on duty */
#define MAX77650_LED_B_DEFAULT          GENMASK(3, 0)

struct max77650_led {
        struct led_classdev cdev;
        struct regmap *map;
        unsigned int regA;
        unsigned int regB;
};

static struct max77650_led *max77650_to_led(struct led_classdev *cdev)
{
        return container_of(cdev, struct max77650_led, cdev);
}

static int max77650_led_brightness_set(struct led_classdev *cdev,
                                       enum led_brightness brightness)
{
        struct max77650_led *led = max77650_to_led(cdev);
        int val, mask;

        mask = MAX77650_LED_BR_MASK | MAX77650_LED_EN_MASK;

        if (brightness == LED_OFF)
                val = MAX77650_LED_DISABLE;
        else
                val = MAX77650_LED_ENABLE | brightness;

        return regmap_update_bits(led->map, led->regA, mask, val);
}

static int max77650_led_probe(struct platform_device *pdev)
{
        struct max77650_led *leds, *led;
        struct device *dev;
        struct regmap *map;
        int rv, num_leds;
        u32 reg;

        dev = &pdev->dev;

        leds = devm_kcalloc(dev, sizeof(*leds),
                            MAX77650_LED_NUM_LEDS, GFP_KERNEL);
        if (!leds)
                return -ENOMEM;

        map = dev_get_regmap(dev->parent, NULL);
        if (!map)
                return -ENODEV;

        num_leds = device_get_child_node_count(dev);
        if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS)
                return -ENODEV;

        device_for_each_child_node_scoped(dev, child) {
                struct led_init_data init_data = {};

                rv = fwnode_property_read_u32(child, "reg", &reg);
                if (rv || reg >= MAX77650_LED_NUM_LEDS)
                        return -EINVAL;

                led = &leds[reg];
                led->map = map;
                led->regA = MAX77650_LED_A_BASE + reg;
                led->regB = MAX77650_LED_B_BASE + reg;
                led->cdev.brightness_set_blocking = max77650_led_brightness_set;
                led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS;

                init_data.fwnode = child;
                init_data.devicename = "max77650";
                /* for backwards compatibility if `label` is not present */
                init_data.default_label = ":";

                rv = devm_led_classdev_register_ext(dev, &led->cdev,
                                                    &init_data);
                if (rv)
                        return rv;

                rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT);
                if (rv)
                        return rv;

                rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT);
                if (rv)
                        return rv;
        }

        return regmap_write(map,
                            MAX77650_REG_CNFG_LED_TOP,
                            MAX77650_LED_TOP_DEFAULT);
}

static const struct of_device_id max77650_led_of_match[] = {
        { .compatible = "maxim,max77650-led" },
        { }
};
MODULE_DEVICE_TABLE(of, max77650_led_of_match);

static struct platform_driver max77650_led_driver = {
        .driver = {
                .name = "max77650-led",
                .of_match_table = max77650_led_of_match,
        },
        .probe = max77650_led_probe,
};
module_platform_driver(max77650_led_driver);

MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver");
MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:max77650-led");