// SPDX-License-Identifier: GPL-2.0
//
// Spreadtrum clock infrastructure
//
// Copyright (C) 2017 Spreadtrum, Inc.
// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>

#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#include "common.h"

static const struct regmap_config sprdclk_regmap_config = {
        .reg_bits       = 32,
        .reg_stride     = 4,
        .val_bits       = 32,
        .fast_io        = true,
};

static void sprd_clk_set_regmap(const struct sprd_clk_desc *desc,
                         struct regmap *regmap)
{
        int i;
        struct sprd_clk_common *cclk;

        for (i = 0; i < desc->num_clk_clks; i++) {
                cclk = desc->clk_clks[i];
                if (!cclk)
                        continue;

                cclk->regmap = regmap;
        }
}

int sprd_clk_regmap_init(struct platform_device *pdev,
                         const struct sprd_clk_desc *desc)
{
        void __iomem *base;
        struct device *dev = &pdev->dev;
        struct device_node *node = dev->of_node, *np;
        struct regmap *regmap;
        struct resource *res;
        struct regmap_config reg_config = sprdclk_regmap_config;

        if (of_property_present(node, "sprd,syscon")) {
                regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
                if (IS_ERR(regmap)) {
                        pr_err("%s: failed to get syscon regmap\n", __func__);
                        return PTR_ERR(regmap);
                }
        } else if (of_device_is_compatible(np = of_get_parent(node), "syscon") ||
                   (of_node_put(np), 0)) {
                regmap = device_node_to_regmap(np);
                of_node_put(np);
                if (IS_ERR(regmap)) {
                        dev_err(dev, "failed to get regmap from its parent.\n");
                        return PTR_ERR(regmap);
                }
        } else {
                base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
                if (IS_ERR(base))
                        return PTR_ERR(base);

                reg_config.max_register = resource_size(res) - reg_config.reg_stride;

                regmap = devm_regmap_init_mmio(&pdev->dev, base,
                                               &reg_config);
                if (IS_ERR(regmap)) {
                        pr_err("failed to init regmap\n");
                        return PTR_ERR(regmap);
                }
        }

        sprd_clk_set_regmap(desc, regmap);

        return 0;
}
EXPORT_SYMBOL_GPL(sprd_clk_regmap_init);

int sprd_clk_probe(struct device *dev, struct clk_hw_onecell_data *clkhw)
{
        int i, ret;
        struct clk_hw *hw;

        for (i = 0; i < clkhw->num; i++) {
                const char *name;

                hw = clkhw->hws[i];
                if (!hw)
                        continue;

                name = hw->init->name;
                ret = devm_clk_hw_register(dev, hw);
                if (ret) {
                        dev_err(dev, "Couldn't register clock %d - %s\n",
                                i, name);
                        return ret;
                }
        }

        ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clkhw);
        if (ret)
                dev_err(dev, "Failed to add clock provider\n");

        return ret;
}
EXPORT_SYMBOL_GPL(sprd_clk_probe);

MODULE_DESCRIPTION("Spreadtrum clock infrastructure");
MODULE_LICENSE("GPL v2");