// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2025 Pengutronix
 *
 * Author: Steffen Trumtrar <kernel@pengutronix.de>
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>

#include "leds-lp5860.h"

#define LP5860_SPI_WRITE_FLAG BIT(13)

/*
 * The lp5860 uses a rather uncommon SPI data format: The R/W flag is on BIT(5) in the two address
 * bytes; BIT(4) to BIT(0) are don't care. Therefore it has 10 bits for the address and 6 bits for
 * padding the address. The address bytes are sent MSB first. Matching the cores registers to regmap
 * results in write_flag_mask being BIT(13).
 */
static const struct regmap_config lp5860_regmap_config = {
        .name = "lp5860",
        .reg_bits = 10,
        .pad_bits = 6,
        .val_bits = 8,
        .write_flag_mask = LP5860_SPI_WRITE_FLAG,
        .reg_format_endian = REGMAP_ENDIAN_BIG,
        .max_register = LP5860_MAX_REG,
};

static int lp5860_probe(struct spi_device *spi)
{
        struct device *dev = &spi->dev;
        struct lp5860 *lp5860;
        unsigned int multi_leds;

        multi_leds = device_get_child_node_count(dev);
        if (!multi_leds) {
                dev_err(dev, "LEDs are not defined in Device Tree!");
                return -ENODEV;
        }

        if (multi_leds > LP5860_MAX_LED) {
                dev_err(dev, "Too many LEDs specified.\n");
                return -EINVAL;
        }

        lp5860 = devm_kzalloc(dev, struct_size(lp5860, leds, multi_leds),
                              GFP_KERNEL);
        if (!lp5860)
                return -ENOMEM;

        lp5860->regmap = devm_regmap_init_spi(spi, &lp5860_regmap_config);
        if (IS_ERR(lp5860->regmap))
                return dev_err_probe(&spi->dev, PTR_ERR(lp5860->regmap),
                                     "Failed to initialise Regmap.\n");

        lp5860->dev = dev;
        mutex_init(&lp5860->lock);

        spi_set_drvdata(spi, lp5860);

        return lp5860_device_init(dev);
}

static void lp5860_remove(struct spi_device *spi)
{
        struct lp5860 *lp5860 = spi_get_drvdata(spi);

        mutex_destroy(&lp5860->lock);

        lp5860_device_remove(&spi->dev);
}

static const struct of_device_id lp5860_of_match[] = {
        { .compatible = "ti,lp5860" },
        {}
};
MODULE_DEVICE_TABLE(of, lp5860_of_match);

static struct spi_driver lp5860_driver = {
        .driver = {
                .name = "lp5860-spi",
                .of_match_table = lp5860_of_match,
        },
        .probe  = lp5860_probe,
        .remove = lp5860_remove,
};
module_spi_driver(lp5860_driver);

MODULE_AUTHOR("Steffen Trumtrar <kernel@pengutronix.de>");
MODULE_DESCRIPTION("TI LP5860 RGB LED SPI driver");
MODULE_LICENSE("GPL");