// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 2012 Freescale Semiconductor, Inc.
 */

#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include "clk.h"

/**
 * struct clk_pll - mxs pll clock
 * @hw: clk_hw for the pll
 * @base: base address of the pll
 * @power: the shift of power bit
 * @rate: the clock rate of the pll
 *
 * The mxs pll is a fixed rate clock with power and gate control,
 * and the shift of gate bit is always 31.
 */
struct clk_pll {
        struct clk_hw hw;
        void __iomem *base;
        u8 power;
        unsigned long rate;
};

#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw)

static int clk_pll_prepare(struct clk_hw *hw)
{
        struct clk_pll *pll = to_clk_pll(hw);

        writel_relaxed(1 << pll->power, pll->base + SET);

        udelay(10);

        return 0;
}

static void clk_pll_unprepare(struct clk_hw *hw)
{
        struct clk_pll *pll = to_clk_pll(hw);

        writel_relaxed(1 << pll->power, pll->base + CLR);
}

static int clk_pll_enable(struct clk_hw *hw)
{
        struct clk_pll *pll = to_clk_pll(hw);

        writel_relaxed(1 << 31, pll->base + CLR);

        return 0;
}

static void clk_pll_disable(struct clk_hw *hw)
{
        struct clk_pll *pll = to_clk_pll(hw);

        writel_relaxed(1 << 31, pll->base + SET);
}

static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
                                         unsigned long parent_rate)
{
        struct clk_pll *pll = to_clk_pll(hw);

        return pll->rate;
}

static const struct clk_ops clk_pll_ops = {
        .prepare = clk_pll_prepare,
        .unprepare = clk_pll_unprepare,
        .enable = clk_pll_enable,
        .disable = clk_pll_disable,
        .recalc_rate = clk_pll_recalc_rate,
};

struct clk *mxs_clk_pll(const char *name, const char *parent_name,
                        void __iomem *base, u8 power, unsigned long rate)
{
        struct clk_pll *pll;
        struct clk *clk;
        struct clk_init_data init;

        pll = kzalloc_obj(*pll);
        if (!pll)
                return ERR_PTR(-ENOMEM);

        init.name = name;
        init.ops = &clk_pll_ops;
        init.flags = 0;
        init.parent_names = (parent_name ? &parent_name: NULL);
        init.num_parents = (parent_name ? 1 : 0);

        pll->base = base;
        pll->rate = rate;
        pll->power = power;
        pll->hw.init = &init;

        clk = clk_register(NULL, &pll->hw);
        if (IS_ERR(clk))
                kfree(pll);

        return clk;
}