// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2014 Free Electrons
 * Copyright (C) 2014 Atmel
 *
 * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
 */

#include <linux/clk.h>
#include <linux/iopoll.h>
#include <linux/mfd/atmel-hlcdc.h>
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define ATMEL_HLCDC_REG_MAX             (0x4000 - 0x4)

struct atmel_hlcdc_regmap {
        void __iomem *regs;
        struct device *dev;
};

static const struct mfd_cell atmel_hlcdc_cells[] = {
        {
                .name = "atmel-hlcdc-pwm",
                .of_compatible = "atmel,hlcdc-pwm",
        },
        {
                .name = "atmel-hlcdc-dc",
                .of_compatible = "atmel,hlcdc-display-controller",
        },
};

static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
                                        unsigned int val)
{
        struct atmel_hlcdc_regmap *hregmap = context;

        if (reg <= ATMEL_HLCDC_DIS) {
                u32 status;
                int ret;

                ret = readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
                                                status,
                                                !(status & ATMEL_HLCDC_SIP),
                                                1, 100);
                if (ret) {
                        dev_err(hregmap->dev,
                                "Timeout! Clock domain synchronization is in progress!\n");
                        return ret;
                }
        }

        writel(val, hregmap->regs + reg);

        return 0;
}

static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
                                       unsigned int *val)
{
        struct atmel_hlcdc_regmap *hregmap = context;

        *val = readl(hregmap->regs + reg);

        return 0;
}

static const struct regmap_config atmel_hlcdc_regmap_config = {
        .reg_bits = 32,
        .val_bits = 32,
        .reg_stride = 4,
        .max_register = ATMEL_HLCDC_REG_MAX,
        .reg_write = regmap_atmel_hlcdc_reg_write,
        .reg_read = regmap_atmel_hlcdc_reg_read,
        .fast_io = true,
};

static int atmel_hlcdc_probe(struct platform_device *pdev)
{
        struct atmel_hlcdc_regmap *hregmap;
        struct device *dev = &pdev->dev;
        struct atmel_hlcdc *hlcdc;

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

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

        hregmap->regs = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(hregmap->regs))
                return PTR_ERR(hregmap->regs);

        hregmap->dev = &pdev->dev;

        hlcdc->irq = platform_get_irq(pdev, 0);
        if (hlcdc->irq < 0)
                return hlcdc->irq;

        hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
        if (IS_ERR(hlcdc->periph_clk)) {
                dev_err(dev, "failed to get peripheral clock\n");
                return PTR_ERR(hlcdc->periph_clk);
        }

        hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
        if (IS_ERR(hlcdc->sys_clk)) {
                dev_err(dev, "failed to get system clock\n");
                return PTR_ERR(hlcdc->sys_clk);
        }

        hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
        if (IS_ERR(hlcdc->slow_clk)) {
                dev_err(dev, "failed to get slow clock\n");
                return PTR_ERR(hlcdc->slow_clk);
        }

        hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
                                         &atmel_hlcdc_regmap_config);
        if (IS_ERR(hlcdc->regmap))
                return PTR_ERR(hlcdc->regmap);

        dev_set_drvdata(dev, hlcdc);

        return devm_mfd_add_devices(dev, -1, atmel_hlcdc_cells,
                                    ARRAY_SIZE(atmel_hlcdc_cells),
                                    NULL, 0, NULL);
}

static const struct of_device_id atmel_hlcdc_match[] = {
        { .compatible = "atmel,at91sam9n12-hlcdc" },
        { .compatible = "atmel,at91sam9x5-hlcdc" },
        { .compatible = "atmel,sama5d2-hlcdc" },
        { .compatible = "atmel,sama5d3-hlcdc" },
        { .compatible = "atmel,sama5d4-hlcdc" },
        { .compatible = "microchip,sam9x60-hlcdc" },
        { .compatible = "microchip,sam9x75-xlcdc" },
        { .compatible = "microchip,sama7d65-xlcdc" },
        { /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);

static struct platform_driver atmel_hlcdc_driver = {
        .probe = atmel_hlcdc_probe,
        .driver = {
                .name = "atmel-hlcdc",
                .of_match_table = atmel_hlcdc_match,
        },
};
module_platform_driver(atmel_hlcdc_driver);

MODULE_ALIAS("platform:atmel-hlcdc");
MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
MODULE_DESCRIPTION("Atmel HLCDC driver");
MODULE_LICENSE("GPL v2");