// SPDX-License-Identifier: GPL-2.0-only
/*
 * Sanyo LV5207LP LED Driver
 *
 * Copyright (C) 2013 Ideas on board SPRL
 *
 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 */

#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/platform_data/lv5207lp.h>
#include <linux/slab.h>

#define LV5207LP_CTRL1                  0x00
#define LV5207LP_CPSW                   (1 << 7)
#define LV5207LP_SCTEN                  (1 << 6)
#define LV5207LP_C10                    (1 << 5)
#define LV5207LP_CKSW                   (1 << 4)
#define LV5207LP_RSW                    (1 << 3)
#define LV5207LP_GSW                    (1 << 2)
#define LV5207LP_BSW                    (1 << 1)
#define LV5207LP_CTRL2                  0x01
#define LV5207LP_MSW                    (1 << 7)
#define LV5207LP_MLED4                  (1 << 6)
#define LV5207LP_RED                    0x02
#define LV5207LP_GREEN                  0x03
#define LV5207LP_BLUE                   0x04

#define LV5207LP_MAX_BRIGHTNESS         32

struct lv5207lp {
        struct i2c_client *client;
        struct backlight_device *backlight;
        struct lv5207lp_platform_data *pdata;
};

static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
{
        return i2c_smbus_write_byte_data(lv->client, reg, data);
}

static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
{
        struct lv5207lp *lv = bl_get_data(backlight);
        int brightness = backlight_get_brightness(backlight);

        if (brightness) {
                lv5207lp_write(lv, LV5207LP_CTRL1,
                               LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
                lv5207lp_write(lv, LV5207LP_CTRL2,
                               LV5207LP_MSW | LV5207LP_MLED4 |
                               (brightness - 1));
        } else {
                lv5207lp_write(lv, LV5207LP_CTRL1, 0);
                lv5207lp_write(lv, LV5207LP_CTRL2, 0);
        }

        return 0;
}

static bool lv5207lp_backlight_controls_device(struct backlight_device *backlight,
                                               struct device *display_dev)
{
        struct lv5207lp *lv = bl_get_data(backlight);

        return !lv->pdata->dev || lv->pdata->dev == display_dev;
}

static const struct backlight_ops lv5207lp_backlight_ops = {
        .options         = BL_CORE_SUSPENDRESUME,
        .update_status   = lv5207lp_backlight_update_status,
        .controls_device = lv5207lp_backlight_controls_device,
};

static int lv5207lp_probe(struct i2c_client *client)
{
        struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
        struct backlight_device *backlight;
        struct backlight_properties props;
        struct lv5207lp *lv;

        if (pdata == NULL) {
                dev_err(&client->dev, "No platform data supplied\n");
                return -EINVAL;
        }

        if (!i2c_check_functionality(client->adapter,
                                     I2C_FUNC_SMBUS_BYTE_DATA)) {
                dev_warn(&client->dev,
                         "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
                return -EIO;
        }

        lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
        if (!lv)
                return -ENOMEM;

        lv->client = client;
        lv->pdata = pdata;

        memset(&props, 0, sizeof(props));
        props.type = BACKLIGHT_RAW;
        props.max_brightness = min_t(unsigned int, pdata->max_value,
                                     LV5207LP_MAX_BRIGHTNESS);
        props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
                                   props.max_brightness);

        backlight = devm_backlight_device_register(&client->dev,
                                dev_name(&client->dev), &lv->client->dev,
                                lv, &lv5207lp_backlight_ops, &props);
        if (IS_ERR(backlight)) {
                dev_err(&client->dev, "failed to register backlight\n");
                return PTR_ERR(backlight);
        }

        backlight_update_status(backlight);
        i2c_set_clientdata(client, backlight);

        return 0;
}

static void lv5207lp_remove(struct i2c_client *client)
{
        struct backlight_device *backlight = i2c_get_clientdata(client);

        backlight->props.brightness = 0;
        backlight_update_status(backlight);
}

static const struct i2c_device_id lv5207lp_ids[] = {
        { "lv5207lp" },
        { }
};
MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);

static struct i2c_driver lv5207lp_driver = {
        .driver = {
                .name = "lv5207lp",
        },
        .probe = lv5207lp_probe,
        .remove = lv5207lp_remove,
        .id_table = lv5207lp_ids,
};

module_i2c_driver(lv5207lp_driver);

MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
MODULE_LICENSE("GPL");