// SPDX-License-Identifier: GPL-2.0+
//
// clk-s2mps11.c - Clock driver for S2MPS11.
//
// Copyright (C) 2013,2014 Samsung Electornics

#include <linux/module.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/clkdev.h>
#include <linux/regmap.h>
#include <linux/clk-provider.h>
#include <linux/platform_device.h>
#include <linux/mfd/samsung/s2mps11.h>
#include <linux/mfd/samsung/s2mps13.h>
#include <linux/mfd/samsung/s2mps14.h>
#include <linux/mfd/samsung/s5m8767.h>
#include <linux/mfd/samsung/core.h>

#include <dt-bindings/clock/samsung,s2mps11.h>

struct s2mps11_clk {
        struct sec_pmic_dev *iodev;
        struct device_node *clk_np;
        struct clk_hw hw;
        struct clk *clk;
        struct clk_lookup *lookup;
        u32 mask;
        unsigned int reg;
};

static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
{
        return container_of(hw, struct s2mps11_clk, hw);
}

static int s2mps11_clk_prepare(struct clk_hw *hw)
{
        struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);

        return regmap_update_bits(s2mps11->iodev->regmap_pmic,
                                 s2mps11->reg,
                                 s2mps11->mask, s2mps11->mask);
}

static void s2mps11_clk_unprepare(struct clk_hw *hw)
{
        struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);

        regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
                           s2mps11->mask, ~s2mps11->mask);
}

static int s2mps11_clk_is_prepared(struct clk_hw *hw)
{
        int ret;
        u32 val;
        struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);

        ret = regmap_read(s2mps11->iodev->regmap_pmic,
                                s2mps11->reg, &val);
        if (ret < 0)
                return -EINVAL;

        return val & s2mps11->mask;
}

static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        return 32768;
}

static const struct clk_ops s2mps11_clk_ops = {
        .prepare        = s2mps11_clk_prepare,
        .unprepare      = s2mps11_clk_unprepare,
        .is_prepared    = s2mps11_clk_is_prepared,
        .recalc_rate    = s2mps11_clk_recalc_rate,
};

/* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
        [S2MPS11_CLK_AP] = {
                .name = "s2mps11_ap",
                .ops = &s2mps11_clk_ops,
        },
        [S2MPS11_CLK_CP] = {
                .name = "s2mps11_cp",
                .ops = &s2mps11_clk_ops,
        },
        [S2MPS11_CLK_BT] = {
                .name = "s2mps11_bt",
                .ops = &s2mps11_clk_ops,
        },
};

static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
                struct clk_init_data *clks_init)
{
        struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
        struct device_node *clk_np;
        int i;

        if (!iodev->dev->of_node)
                return ERR_PTR(-EINVAL);

        clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
        if (!clk_np) {
                dev_err(&pdev->dev, "could not find clock sub-node\n");
                return ERR_PTR(-EINVAL);
        }

        for (i = 0; i < S2MPS11_CLKS_NUM; i++)
                of_property_read_string_index(clk_np, "clock-output-names", i,
                                &clks_init[i].name);

        return clk_np;
}

static int s2mps11_clk_probe(struct platform_device *pdev)
{
        struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
        struct s2mps11_clk *s2mps11_clks;
        struct clk_hw_onecell_data *clk_data;
        unsigned int s2mps11_reg;
        int i, ret = 0;
        enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;

        s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
                                sizeof(*s2mps11_clks), GFP_KERNEL);
        if (!s2mps11_clks)
                return -ENOMEM;

        clk_data = devm_kzalloc(&pdev->dev,
                                struct_size(clk_data, hws, S2MPS11_CLKS_NUM),
                                GFP_KERNEL);
        if (!clk_data)
                return -ENOMEM;

        switch (hwid) {
        case S2MPS11X:
                s2mps11_reg = S2MPS11_REG_RTC_CTRL;
                break;
        case S2MPS13X:
                s2mps11_reg = S2MPS13_REG_RTCCTRL;
                break;
        case S2MPS14X:
                s2mps11_reg = S2MPS14_REG_RTCCTRL;
                break;
        case S5M8767X:
                s2mps11_reg = S5M8767_REG_CTRL1;
                break;
        default:
                dev_err(&pdev->dev, "Invalid device type\n");
                return -EINVAL;
        }

        /* Store clocks of_node in first element of s2mps11_clks array */
        s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
        if (IS_ERR(s2mps11_clks->clk_np))
                return PTR_ERR(s2mps11_clks->clk_np);

        for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
                if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
                        continue; /* Skip clocks not present in some devices */
                s2mps11_clks[i].iodev = iodev;
                s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
                s2mps11_clks[i].mask = 1 << i;
                s2mps11_clks[i].reg = s2mps11_reg;

                s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
                                                        &s2mps11_clks[i].hw);
                if (IS_ERR(s2mps11_clks[i].clk)) {
                        dev_err(&pdev->dev, "Fail to register : %s\n",
                                                s2mps11_clks_init[i].name);
                        ret = PTR_ERR(s2mps11_clks[i].clk);
                        goto err_reg;
                }

                s2mps11_clks[i].lookup = clkdev_hw_create(&s2mps11_clks[i].hw,
                                        s2mps11_clks_init[i].name, NULL);
                if (!s2mps11_clks[i].lookup) {
                        ret = -ENOMEM;
                        goto err_reg;
                }
                clk_data->hws[i] = &s2mps11_clks[i].hw;
        }

        clk_data->num = S2MPS11_CLKS_NUM;
        of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
                               clk_data);

        platform_set_drvdata(pdev, s2mps11_clks);

        return ret;

err_reg:
        of_node_put(s2mps11_clks[0].clk_np);
        while (--i >= 0)
                clkdev_drop(s2mps11_clks[i].lookup);

        return ret;
}

static int s2mps11_clk_remove(struct platform_device *pdev)
{
        struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
        int i;

        of_clk_del_provider(s2mps11_clks[0].clk_np);
        /* Drop the reference obtained in s2mps11_clk_parse_dt */
        of_node_put(s2mps11_clks[0].clk_np);

        for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
                /* Skip clocks not present on S2MPS14 */
                if (!s2mps11_clks[i].lookup)
                        continue;
                clkdev_drop(s2mps11_clks[i].lookup);
        }

        return 0;
}

static const struct platform_device_id s2mps11_clk_id[] = {
        { "s2mps11-clk", S2MPS11X},
        { "s2mps13-clk", S2MPS13X},
        { "s2mps14-clk", S2MPS14X},
        { "s5m8767-clk", S5M8767X},
        { },
};
MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);

#ifdef CONFIG_OF
/*
 * Device is instantiated through parent MFD device and device matching is done
 * through platform_device_id.
 *
 * However if device's DT node contains proper clock compatible and driver is
 * built as a module, then the *module* matching will be done trough DT aliases.
 * This requires of_device_id table.  In the same time this will not change the
 * actual *device* matching so do not add .of_match_table.
 */
static const struct of_device_id s2mps11_dt_match[] __used = {
        {
                .compatible = "samsung,s2mps11-clk",
                .data = (void *)S2MPS11X,
        }, {
                .compatible = "samsung,s2mps13-clk",
                .data = (void *)S2MPS13X,
        }, {
                .compatible = "samsung,s2mps14-clk",
                .data = (void *)S2MPS14X,
        }, {
                .compatible = "samsung,s5m8767-clk",
                .data = (void *)S5M8767X,
        }, {
                /* Sentinel */
        },
};
MODULE_DEVICE_TABLE(of, s2mps11_dt_match);
#endif

static struct platform_driver s2mps11_clk_driver = {
        .driver = {
                .name  = "s2mps11-clk",
        },
        .probe = s2mps11_clk_probe,
        .remove = s2mps11_clk_remove,
        .id_table = s2mps11_clk_id,
};
module_platform_driver(s2mps11_clk_driver);

MODULE_DESCRIPTION("S2MPS11 Clock Driver");
MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
MODULE_LICENSE("GPL");