// SPDX-License-Identifier: GPL-2.0-only
/*
* Simple driver for Texas Instruments LM3639 Backlight + Flash LED driver chip
* Copyright (C) 2012 Texas Instruments
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/regmap.h>
#include <linux/platform_data/lm3639_bl.h>

#define REG_DEV_ID      0x00
#define REG_CHECKSUM    0x01
#define REG_BL_CONF_1   0x02
#define REG_BL_CONF_2   0x03
#define REG_BL_CONF_3   0x04
#define REG_BL_CONF_4   0x05
#define REG_FL_CONF_1   0x06
#define REG_FL_CONF_2   0x07
#define REG_FL_CONF_3   0x08
#define REG_IO_CTRL     0x09
#define REG_ENABLE      0x0A
#define REG_FLAG        0x0B
#define REG_MAX         REG_FLAG

struct lm3639_chip_data {
        struct device *dev;
        struct lm3639_platform_data *pdata;

        struct backlight_device *bled;
        struct led_classdev cdev_flash;
        struct led_classdev cdev_torch;
        struct regmap *regmap;

        unsigned int bled_mode;
        unsigned int bled_map;
        unsigned int last_flag;
};

/* initialize chip */
static int lm3639_chip_init(struct lm3639_chip_data *pchip)
{
        int ret;
        unsigned int reg_val;
        struct lm3639_platform_data *pdata = pchip->pdata;

        /* input pins config. */
        ret =
            regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x08,
                               pdata->pin_pwm);
        if (ret < 0)
                goto out;

        reg_val = (pdata->pin_pwm & 0x40) | pdata->pin_strobe | pdata->pin_tx;
        ret = regmap_update_bits(pchip->regmap, REG_IO_CTRL, 0x7C, reg_val);
        if (ret < 0)
                goto out;

        /* init brightness */
        ret = regmap_write(pchip->regmap, REG_BL_CONF_4, pdata->init_brt_led);
        if (ret < 0)
                goto out;

        ret = regmap_write(pchip->regmap, REG_BL_CONF_3, pdata->init_brt_led);
        if (ret < 0)
                goto out;

        /* output pins config. */
        if (!pdata->init_brt_led) {
                reg_val = pdata->fled_pins;
                reg_val |= pdata->bled_pins;
        } else {
                reg_val = pdata->fled_pins;
                reg_val |= pdata->bled_pins | 0x01;
        }

        ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x79, reg_val);
        if (ret < 0)
                goto out;

        return ret;
out:
        dev_err(pchip->dev, "i2c failed to access register\n");
        return ret;
}

/* update and get brightness */
static int lm3639_bled_update_status(struct backlight_device *bl)
{
        int ret;
        unsigned int reg_val;
        struct lm3639_chip_data *pchip = bl_get_data(bl);
        struct lm3639_platform_data *pdata = pchip->pdata;

        ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
        if (ret < 0)
                goto out;

        if (reg_val != 0)
                dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);

        /* pwm control */
        if (pdata->pin_pwm) {
                if (pdata->pwm_set_intensity)
                        pdata->pwm_set_intensity(bl->props.brightness,
                                                 pdata->max_brt_led);
                else
                        dev_err(pchip->dev,
                                "No pwm control func. in plat-data\n");
                return bl->props.brightness;
        }

        /* i2c control and set brigtness */
        ret = regmap_write(pchip->regmap, REG_BL_CONF_4, bl->props.brightness);
        if (ret < 0)
                goto out;
        ret = regmap_write(pchip->regmap, REG_BL_CONF_3, bl->props.brightness);
        if (ret < 0)
                goto out;

        if (!bl->props.brightness)
                ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x00);
        else
                ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x01);
        if (ret < 0)
                goto out;

        return bl->props.brightness;
out:
        dev_err(pchip->dev, "i2c failed to access registers\n");
        return bl->props.brightness;
}

static int lm3639_bled_get_brightness(struct backlight_device *bl)
{
        int ret;
        unsigned int reg_val;
        struct lm3639_chip_data *pchip = bl_get_data(bl);
        struct lm3639_platform_data *pdata = pchip->pdata;

        if (pdata->pin_pwm) {
                if (pdata->pwm_get_intensity)
                        bl->props.brightness = pdata->pwm_get_intensity();
                else
                        dev_err(pchip->dev,
                                "No pwm control func. in plat-data\n");
                return bl->props.brightness;
        }

        ret = regmap_read(pchip->regmap, REG_BL_CONF_1, &reg_val);
        if (ret < 0)
                goto out;
        if (reg_val & 0x10)
                ret = regmap_read(pchip->regmap, REG_BL_CONF_4, &reg_val);
        else
                ret = regmap_read(pchip->regmap, REG_BL_CONF_3, &reg_val);
        if (ret < 0)
                goto out;
        bl->props.brightness = reg_val;

        return bl->props.brightness;
out:
        dev_err(pchip->dev, "i2c failed to access register\n");
        return bl->props.brightness;
}

static const struct backlight_ops lm3639_bled_ops = {
        .options = BL_CORE_SUSPENDRESUME,
        .update_status = lm3639_bled_update_status,
        .get_brightness = lm3639_bled_get_brightness,
};

/* backlight mapping mode */
static ssize_t lm3639_bled_mode_store(struct device *dev,
                                      struct device_attribute *devAttr,
                                      const char *buf, size_t size)
{
        ssize_t ret;
        struct lm3639_chip_data *pchip = dev_get_drvdata(dev);
        unsigned int state;

        ret = kstrtouint(buf, 10, &state);
        if (ret)
                goto out_input;

        if (!state)
                ret =
                    regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
                                       0x00);
        else
                ret =
                    regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
                                       0x10);

        if (ret < 0)
                goto out;

        return size;

out:
        dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
        return ret;

out_input:
        dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
        return ret;

}

static DEVICE_ATTR(bled_mode, S_IWUSR, NULL, lm3639_bled_mode_store);

/* torch */
static void lm3639_torch_brightness_set(struct led_classdev *cdev,
                                        enum led_brightness brightness)
{
        int ret;
        unsigned int reg_val;
        struct lm3639_chip_data *pchip;

        pchip = container_of(cdev, struct lm3639_chip_data, cdev_torch);

        ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
        if (ret < 0)
                goto out;
        if (reg_val != 0)
                dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);

        /* brightness 0 means off state */
        if (!brightness) {
                ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
                if (ret < 0)
                        goto out;
                return;
        }

        ret = regmap_update_bits(pchip->regmap,
                                 REG_FL_CONF_1, 0x70, (brightness - 1) << 4);
        if (ret < 0)
                goto out;
        ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x02);
        if (ret < 0)
                goto out;

        return;
out:
        dev_err(pchip->dev, "i2c failed to access register\n");
}

/* flash */
static void lm3639_flash_brightness_set(struct led_classdev *cdev,
                                        enum led_brightness brightness)
{
        int ret;
        unsigned int reg_val;
        struct lm3639_chip_data *pchip;

        pchip = container_of(cdev, struct lm3639_chip_data, cdev_flash);

        ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
        if (ret < 0)
                goto out;
        if (reg_val != 0)
                dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);

        /* torch off before flash control */
        ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
        if (ret < 0)
                goto out;

        /* brightness 0 means off state */
        if (!brightness)
                return;

        ret = regmap_update_bits(pchip->regmap,
                                 REG_FL_CONF_1, 0x0F, brightness - 1);
        if (ret < 0)
                goto out;
        ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x06);
        if (ret < 0)
                goto out;

        return;
out:
        dev_err(pchip->dev, "i2c failed to access register\n");
}

static const struct regmap_config lm3639_regmap = {
        .reg_bits = 8,
        .val_bits = 8,
        .max_register = REG_MAX,
};

static int lm3639_probe(struct i2c_client *client)
{
        int ret;
        struct lm3639_chip_data *pchip;
        struct lm3639_platform_data *pdata = dev_get_platdata(&client->dev);
        struct backlight_properties props;

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
                dev_err(&client->dev, "i2c functionality check fail.\n");
                return -EOPNOTSUPP;
        }

        if (pdata == NULL) {
                dev_err(&client->dev, "Needs Platform Data.\n");
                return -ENODATA;
        }

        pchip = devm_kzalloc(&client->dev,
                             sizeof(struct lm3639_chip_data), GFP_KERNEL);
        if (!pchip)
                return -ENOMEM;

        pchip->pdata = pdata;
        pchip->dev = &client->dev;

        pchip->regmap = devm_regmap_init_i2c(client, &lm3639_regmap);
        if (IS_ERR(pchip->regmap)) {
                ret = PTR_ERR(pchip->regmap);
                dev_err(&client->dev, "fail : allocate register map: %d\n",
                        ret);
                return ret;
        }
        i2c_set_clientdata(client, pchip);

        /* chip initialize */
        ret = lm3639_chip_init(pchip);
        if (ret < 0) {
                dev_err(&client->dev, "fail : chip init\n");
                goto err_out;
        }

        /* backlight */
        memset(&props, 0, sizeof(struct backlight_properties));
        props.type = BACKLIGHT_RAW;
        props.brightness = pdata->init_brt_led;
        props.max_brightness = pdata->max_brt_led;
        pchip->bled =
            devm_backlight_device_register(pchip->dev, "lm3639_bled",
                                           pchip->dev, pchip, &lm3639_bled_ops,
                                           &props);
        if (IS_ERR(pchip->bled)) {
                dev_err(&client->dev, "fail : backlight register\n");
                ret = PTR_ERR(pchip->bled);
                goto err_out;
        }

        ret = device_create_file(&(pchip->bled->dev), &dev_attr_bled_mode);
        if (ret < 0) {
                dev_err(&client->dev, "failed : add sysfs entries\n");
                goto err_out;
        }

        /* flash */
        pchip->cdev_flash.name = "lm3639_flash";
        pchip->cdev_flash.max_brightness = 16;
        pchip->cdev_flash.brightness_set = lm3639_flash_brightness_set;
        ret = led_classdev_register((struct device *)
                                    &client->dev, &pchip->cdev_flash);
        if (ret < 0) {
                dev_err(&client->dev, "fail : flash register\n");
                goto err_flash;
        }

        /* torch */
        pchip->cdev_torch.name = "lm3639_torch";
        pchip->cdev_torch.max_brightness = 8;
        pchip->cdev_torch.brightness_set = lm3639_torch_brightness_set;
        ret = led_classdev_register((struct device *)
                                    &client->dev, &pchip->cdev_torch);
        if (ret < 0) {
                dev_err(&client->dev, "fail : torch register\n");
                goto err_torch;
        }

        return 0;

err_torch:
        led_classdev_unregister(&pchip->cdev_flash);
err_flash:
        device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
err_out:
        return ret;
}

static void lm3639_remove(struct i2c_client *client)
{
        struct lm3639_chip_data *pchip = i2c_get_clientdata(client);

        regmap_write(pchip->regmap, REG_ENABLE, 0x00);

        led_classdev_unregister(&pchip->cdev_torch);
        led_classdev_unregister(&pchip->cdev_flash);
        if (pchip->bled)
                device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
}

static const struct i2c_device_id lm3639_id[] = {
        { LM3639_NAME },
        {}
};

MODULE_DEVICE_TABLE(i2c, lm3639_id);
static struct i2c_driver lm3639_i2c_driver = {
        .driver = {
                   .name = LM3639_NAME,
                   },
        .probe = lm3639_probe,
        .remove = lm3639_remove,
        .id_table = lm3639_id,
};

module_i2c_driver(lm3639_i2c_driver);

MODULE_DESCRIPTION("Texas Instruments Backlight+Flash LED driver for LM3639");
MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
MODULE_LICENSE("GPL v2");