// SPDX-License-Identifier: GPL-2.0
//
// reset-uniphier-glue.c - Glue layer reset driver for UniPhier
// Copyright 2018 Socionext Inc.
// Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/reset/reset-simple.h>

#define MAX_CLKS        2
#define MAX_RSTS        2

struct uniphier_glue_reset_soc_data {
        int nclks;
        const char * const *clock_names;
        int nrsts;
        const char * const *reset_names;
};

struct uniphier_glue_reset_priv {
        struct clk_bulk_data clk[MAX_CLKS];
        struct reset_control_bulk_data rst[MAX_RSTS];
        struct reset_simple_data rdata;
        const struct uniphier_glue_reset_soc_data *data;
};

static void uniphier_clk_disable(void *_priv)
{
        struct uniphier_glue_reset_priv *priv = _priv;

        clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
}

static int uniphier_glue_reset_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct uniphier_glue_reset_priv *priv;
        struct resource *res;
        int i, ret;

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

        priv->data = of_device_get_match_data(dev);
        if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
                    priv->data->nrsts > MAX_RSTS))
                return -EINVAL;

        priv->rdata.membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(priv->rdata.membase))
                return PTR_ERR(priv->rdata.membase);

        for (i = 0; i < priv->data->nclks; i++)
                priv->clk[i].id = priv->data->clock_names[i];
        ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
        if (ret)
                return ret;

        ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
        if (ret)
                return ret;

        ret = devm_add_action_or_reset(dev, uniphier_clk_disable, priv);
        if (ret)
                return ret;

        for (i = 0; i < priv->data->nrsts; i++)
                priv->rst[i].id = priv->data->reset_names[i];
        ret = devm_reset_control_bulk_get_shared_deasserted(dev,
                                                            priv->data->nrsts,
                                                            priv->rst);
        if (ret)
                return ret;

        spin_lock_init(&priv->rdata.lock);
        priv->rdata.rcdev.owner = THIS_MODULE;
        priv->rdata.rcdev.nr_resets = resource_size(res) * BITS_PER_BYTE;
        priv->rdata.rcdev.ops = &reset_simple_ops;
        priv->rdata.rcdev.of_node = dev->of_node;
        priv->rdata.active_low = true;

        return devm_reset_controller_register(dev, &priv->rdata.rcdev);
}

static const char * const uniphier_pro4_clock_reset_names[] = {
        "gio", "link",
};

static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
        .nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
        .clock_names = uniphier_pro4_clock_reset_names,
        .nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
        .reset_names = uniphier_pro4_clock_reset_names,
};

static const char * const uniphier_pxs2_clock_reset_names[] = {
        "link",
};

static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
        .nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
        .clock_names = uniphier_pxs2_clock_reset_names,
        .nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
        .reset_names = uniphier_pxs2_clock_reset_names,
};

static const struct of_device_id uniphier_glue_reset_match[] = {
        {
                .compatible = "socionext,uniphier-pro4-usb3-reset",
                .data = &uniphier_pro4_data,
        },
        {
                .compatible = "socionext,uniphier-pro5-usb3-reset",
                .data = &uniphier_pro4_data,
        },
        {
                .compatible = "socionext,uniphier-pxs2-usb3-reset",
                .data = &uniphier_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-ld20-usb3-reset",
                .data = &uniphier_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-pxs3-usb3-reset",
                .data = &uniphier_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-nx1-usb3-reset",
                .data = &uniphier_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-pro4-ahci-reset",
                .data = &uniphier_pro4_data,
        },
        {
                .compatible = "socionext,uniphier-pxs2-ahci-reset",
                .data = &uniphier_pxs2_data,
        },
        {
                .compatible = "socionext,uniphier-pxs3-ahci-reset",
                .data = &uniphier_pxs2_data,
        },
        { /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);

static struct platform_driver uniphier_glue_reset_driver = {
        .probe = uniphier_glue_reset_probe,
        .driver = {
                .name = "uniphier-glue-reset",
                .of_match_table = uniphier_glue_reset_match,
        },
};
module_platform_driver(uniphier_glue_reset_driver);

MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
MODULE_LICENSE("GPL");