// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2017 Sebastian Reichel <sre@kernel.org>
 */

#include <linux/leds.h>
#include <linux/mfd/motorola-cpcap.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>

#define CPCAP_LED_NO_CURRENT 0x0001

struct cpcap_led_info {
        u16 reg;
        u16 mask;
        u16 limit;
        u16 init_mask;
        u16 init_val;
};

static const struct cpcap_led_info cpcap_led_red = {
        .reg    = CPCAP_REG_REDC,
        .mask   = 0x03FF,
        .limit  = 31,
};

static const struct cpcap_led_info cpcap_led_green = {
        .reg    = CPCAP_REG_GREENC,
        .mask   = 0x03FF,
        .limit  = 31,
};

static const struct cpcap_led_info cpcap_led_blue = {
        .reg    = CPCAP_REG_BLUEC,
        .mask   = 0x03FF,
        .limit  = 31,
};

/* aux display light */
static const struct cpcap_led_info cpcap_led_adl = {
        .reg            = CPCAP_REG_ADLC,
        .mask           = 0x000F,
        .limit          = 1,
        .init_mask      = 0x7FFF,
        .init_val       = 0x5FF0,
};

/* camera privacy led */
static const struct cpcap_led_info cpcap_led_cp = {
        .reg            = CPCAP_REG_CLEDC,
        .mask           = 0x0007,
        .limit          = 1,
        .init_mask      = 0x03FF,
        .init_val       = 0x0008,
};

struct cpcap_led {
        struct led_classdev led;
        const struct cpcap_led_info *info;
        struct device *dev;
        struct regmap *regmap;
        struct mutex update_lock;
        struct regulator *vdd;
        bool powered;

        u32 current_limit;
};

static u16 cpcap_led_val(u8 current_limit, u8 duty_cycle)
{
        current_limit &= 0x1f; /* 5 bit */
        duty_cycle &= 0x0f; /* 4 bit */

        return current_limit << 4 | duty_cycle;
}

static int cpcap_led_set_power(struct cpcap_led *led, bool status)
{
        int err;

        if (status == led->powered)
                return 0;

        if (status)
                err = regulator_enable(led->vdd);
        else
                err = regulator_disable(led->vdd);

        if (err) {
                dev_err(led->dev, "regulator failure: %d", err);
                return err;
        }

        led->powered = status;

        return 0;
}

static int cpcap_led_set(struct led_classdev *ledc, enum led_brightness value)
{
        struct cpcap_led *led = container_of(ledc, struct cpcap_led, led);
        int brightness;
        int err;

        mutex_lock(&led->update_lock);

        if (value > LED_OFF) {
                err = cpcap_led_set_power(led, true);
                if (err)
                        goto exit;
        }

        if (value == LED_OFF) {
                /* Avoid HW issue by turning off current before duty cycle */
                err = regmap_update_bits(led->regmap,
                        led->info->reg, led->info->mask, CPCAP_LED_NO_CURRENT);
                if (err) {
                        dev_err(led->dev, "regmap failed: %d", err);
                        goto exit;
                }

                brightness = cpcap_led_val(value, LED_OFF);
        } else {
                brightness = cpcap_led_val(value, LED_ON);
        }

        err = regmap_update_bits(led->regmap, led->info->reg, led->info->mask,
                brightness);
        if (err) {
                dev_err(led->dev, "regmap failed: %d", err);
                goto exit;
        }

        if (value == LED_OFF) {
                err = cpcap_led_set_power(led, false);
                if (err)
                        goto exit;
        }

exit:
        mutex_unlock(&led->update_lock);
        return err;
}

static const struct of_device_id cpcap_led_of_match[] = {
        { .compatible = "motorola,cpcap-led-red", .data = &cpcap_led_red },
        { .compatible = "motorola,cpcap-led-green", .data = &cpcap_led_green },
        { .compatible = "motorola,cpcap-led-blue",  .data = &cpcap_led_blue },
        { .compatible = "motorola,cpcap-led-adl", .data = &cpcap_led_adl },
        { .compatible = "motorola,cpcap-led-cp", .data = &cpcap_led_cp },
        {},
};
MODULE_DEVICE_TABLE(of, cpcap_led_of_match);

static int cpcap_led_probe(struct platform_device *pdev)
{
        struct cpcap_led *led;
        int err;

        led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
        if (!led)
                return -ENOMEM;
        platform_set_drvdata(pdev, led);
        led->info = device_get_match_data(&pdev->dev);
        led->dev = &pdev->dev;

        if (led->info->reg == 0x0000) {
                dev_err(led->dev, "Unsupported LED");
                return -ENODEV;
        }

        led->regmap = dev_get_regmap(pdev->dev.parent, NULL);
        if (!led->regmap)
                return -ENODEV;

        led->vdd = devm_regulator_get(&pdev->dev, "vdd");
        if (IS_ERR(led->vdd)) {
                err = PTR_ERR(led->vdd);
                dev_err(led->dev, "Couldn't get regulator: %d", err);
                return err;
        }

        err = device_property_read_string(&pdev->dev, "label", &led->led.name);
        if (err) {
                dev_err(led->dev, "Couldn't read LED label: %d", err);
                return err;
        }

        if (led->info->init_mask) {
                err = regmap_update_bits(led->regmap, led->info->reg,
                        led->info->init_mask, led->info->init_val);
                if (err) {
                        dev_err(led->dev, "regmap failed: %d", err);
                        return err;
                }
        }

        mutex_init(&led->update_lock);

        led->led.max_brightness = led->info->limit;
        led->led.brightness_set_blocking = cpcap_led_set;
        err = devm_led_classdev_register(&pdev->dev, &led->led);
        if (err) {
                dev_err(led->dev, "Couldn't register LED: %d", err);
                return err;
        }

        return 0;
}

static struct platform_driver cpcap_led_driver = {
        .probe = cpcap_led_probe,
        .driver = {
                .name = "cpcap-led",
                .of_match_table = cpcap_led_of_match,
        },
};
module_platform_driver(cpcap_led_driver);

MODULE_DESCRIPTION("CPCAP LED driver");
MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
MODULE_LICENSE("GPL");