// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2016 Free Electrons
 *
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 */

#include <linux/clk.h>
#include <linux/component.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>

struct sun6i_drc {
        struct clk              *bus_clk;
        struct clk              *mod_clk;
        struct reset_control    *reset;
};

static int sun6i_drc_bind(struct device *dev, struct device *master,
                         void *data)
{
        struct sun6i_drc *drc;
        int ret;

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

        drc->reset = devm_reset_control_get(dev, NULL);
        if (IS_ERR(drc->reset)) {
                dev_err(dev, "Couldn't get our reset line\n");
                return PTR_ERR(drc->reset);
        }

        ret = reset_control_deassert(drc->reset);
        if (ret) {
                dev_err(dev, "Couldn't deassert our reset line\n");
                return ret;
        }

        drc->bus_clk = devm_clk_get(dev, "ahb");
        if (IS_ERR(drc->bus_clk)) {
                dev_err(dev, "Couldn't get our bus clock\n");
                ret = PTR_ERR(drc->bus_clk);
                goto err_assert_reset;
        }
        clk_prepare_enable(drc->bus_clk);

        drc->mod_clk = devm_clk_get(dev, "mod");
        if (IS_ERR(drc->mod_clk)) {
                dev_err(dev, "Couldn't get our mod clock\n");
                ret = PTR_ERR(drc->mod_clk);
                goto err_disable_bus_clk;
        }

        ret = clk_set_rate_exclusive(drc->mod_clk, 300000000);
        if (ret) {
                dev_err(dev, "Couldn't set the module clock frequency\n");
                goto err_disable_bus_clk;
        }

        clk_prepare_enable(drc->mod_clk);

        return 0;

err_disable_bus_clk:
        clk_disable_unprepare(drc->bus_clk);
err_assert_reset:
        reset_control_assert(drc->reset);
        return ret;
}

static void sun6i_drc_unbind(struct device *dev, struct device *master,
                            void *data)
{
        struct sun6i_drc *drc = dev_get_drvdata(dev);

        clk_rate_exclusive_put(drc->mod_clk);
        clk_disable_unprepare(drc->mod_clk);
        clk_disable_unprepare(drc->bus_clk);
        reset_control_assert(drc->reset);
}

static const struct component_ops sun6i_drc_ops = {
        .bind   = sun6i_drc_bind,
        .unbind = sun6i_drc_unbind,
};

static int sun6i_drc_probe(struct platform_device *pdev)
{
        return component_add(&pdev->dev, &sun6i_drc_ops);
}

static void sun6i_drc_remove(struct platform_device *pdev)
{
        component_del(&pdev->dev, &sun6i_drc_ops);
}

static const struct of_device_id sun6i_drc_of_table[] = {
        { .compatible = "allwinner,sun6i-a31-drc" },
        { .compatible = "allwinner,sun6i-a31s-drc" },
        { .compatible = "allwinner,sun8i-a23-drc" },
        { .compatible = "allwinner,sun8i-a33-drc" },
        { .compatible = "allwinner,sun9i-a80-drc" },
        { }
};
MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);

static struct platform_driver sun6i_drc_platform_driver = {
        .probe          = sun6i_drc_probe,
        .remove         = sun6i_drc_remove,
        .driver         = {
                .name           = "sun6i-drc",
                .of_match_table = sun6i_drc_of_table,
        },
};
module_platform_driver(sun6i_drc_platform_driver);

MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");
MODULE_LICENSE("GPL");