// SPDX-License-Identifier: GPL-2.0-only
/*
 * UP board LED driver.
 *
 * Copyright (c) AAEON. All rights reserved.
 * Copyright (C) 2024 Bootlin
 *
 * Author: Gary Wang <garywang@aaeon.com.tw>
 * Author: Thomas Richard <thomas.richard@bootlin.com>
 */

#include <linux/device.h>
#include <linux/container_of.h>
#include <linux/leds.h>
#include <linux/mfd/upboard-fpga.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define led_cdev_to_led_upboard(c)      container_of(c, struct upboard_led, cdev)

struct upboard_led {
        struct regmap_field *field;
        struct led_classdev cdev;
};

struct upboard_led_profile {
        const char *name;
        unsigned int bit;
};

static struct upboard_led_profile upboard_up_led_profile[] = {
        { "upboard:yellow:" LED_FUNCTION_STATUS, 0 },
        { "upboard:green:" LED_FUNCTION_STATUS, 1 },
        { "upboard:red:" LED_FUNCTION_STATUS, 2 },
};

static struct upboard_led_profile upboard_up2_led_profile[] = {
        { "upboard:blue:" LED_FUNCTION_STATUS, 0 },
        { "upboard:yellow:" LED_FUNCTION_STATUS, 1 },
        { "upboard:green:" LED_FUNCTION_STATUS, 2 },
        { "upboard:red:" LED_FUNCTION_STATUS, 3 },
};

static enum led_brightness upboard_led_brightness_get(struct led_classdev *cdev)
{
        struct upboard_led *led = led_cdev_to_led_upboard(cdev);
        int brightness, ret;

        ret = regmap_field_read(led->field, &brightness);

        return ret ? LED_OFF : brightness;
};

static int upboard_led_brightness_set(struct led_classdev *cdev, enum led_brightness brightness)
{
        struct upboard_led *led = led_cdev_to_led_upboard(cdev);

        return regmap_field_write(led->field, brightness != LED_OFF);
};

static int upboard_led_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct upboard_fpga *fpga = dev_get_drvdata(dev->parent);
        struct upboard_led_profile *led_profile;
        struct upboard_led *led;
        int led_instances, ret, i;

        switch (fpga->fpga_data->type) {
        case UPBOARD_UP_FPGA:
                led_profile = upboard_up_led_profile;
                led_instances = ARRAY_SIZE(upboard_up_led_profile);
                break;
        case UPBOARD_UP2_FPGA:
                led_profile = upboard_up2_led_profile;
                led_instances = ARRAY_SIZE(upboard_up2_led_profile);
                break;
        default:
                return dev_err_probe(dev, -EINVAL, "Unknown device type %d\n",
                                     fpga->fpga_data->type);
        }

        for (i = 0; i < led_instances; i++) {
                const struct reg_field fldconf = {
                        .reg = UPBOARD_REG_FUNC_EN0,
                        .lsb = led_profile[i].bit,
                        .msb = led_profile[i].bit,
                };

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

                led->field = devm_regmap_field_alloc(&pdev->dev, fpga->regmap, fldconf);
                if (IS_ERR(led->field))
                        return PTR_ERR(led->field);

                led->cdev.brightness_get = upboard_led_brightness_get;
                led->cdev.brightness_set_blocking = upboard_led_brightness_set;
                led->cdev.max_brightness = LED_ON;

                led->cdev.name = led_profile[i].name;

                ret = devm_led_classdev_register(dev, &led->cdev);
                if (ret)
                        return ret;
        }

        return 0;
}

static struct platform_driver upboard_led_driver = {
        .driver = {
                .name = "upboard-leds",
        },
        .probe = upboard_led_probe,
};

module_platform_driver(upboard_led_driver);

MODULE_AUTHOR("Gary Wang <garywang@aaeon.com.tw>");
MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>");
MODULE_DESCRIPTION("UP Board LED driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:upboard-leds");