// SPDX-License-Identifier: GPL-2.0
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/reset-controller.h>

#include "reset.h"

#define rcdev_to_unit(rcdev) container_of(rcdev, struct mmp_clk_reset_unit, rcdev)

static int mmp_of_reset_xlate(struct reset_controller_dev *rcdev,
                          const struct of_phandle_args *reset_spec)
{
        struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
        struct mmp_clk_reset_cell *cell;
        int i;

        if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
                return -EINVAL;

        for (i = 0; i < rcdev->nr_resets; i++) {
                cell = &unit->cells[i];
                if (cell->clk_id == reset_spec->args[0])
                        break;
        }

        if (i == rcdev->nr_resets)
                return -EINVAL;

        return i;
}

static int mmp_clk_reset_assert(struct reset_controller_dev *rcdev,
                                unsigned long id)
{
        struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
        struct mmp_clk_reset_cell *cell;
        unsigned long flags = 0;
        u32 val;

        cell = &unit->cells[id];
        if (cell->lock)
                spin_lock_irqsave(cell->lock, flags);

        val = readl(cell->reg);
        val |= cell->bits;
        writel(val, cell->reg);

        if (cell->lock)
                spin_unlock_irqrestore(cell->lock, flags);

        return 0;
}

static int mmp_clk_reset_deassert(struct reset_controller_dev *rcdev,
                                unsigned long id)
{
        struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
        struct mmp_clk_reset_cell *cell;
        unsigned long flags = 0;
        u32 val;

        cell = &unit->cells[id];
        if (cell->lock)
                spin_lock_irqsave(cell->lock, flags);

        val = readl(cell->reg);
        val &= ~cell->bits;
        writel(val, cell->reg);

        if (cell->lock)
                spin_unlock_irqrestore(cell->lock, flags);

        return 0;
}

static const struct reset_control_ops mmp_clk_reset_ops = {
        .assert         = mmp_clk_reset_assert,
        .deassert       = mmp_clk_reset_deassert,
};

void mmp_clk_reset_register(struct device_node *np,
                        struct mmp_clk_reset_cell *cells, int nr_resets)
{
        struct mmp_clk_reset_unit *unit;

        unit = kzalloc_obj(*unit);
        if (!unit)
                return;

        unit->cells = cells;
        unit->rcdev.of_reset_n_cells = 1;
        unit->rcdev.nr_resets = nr_resets;
        unit->rcdev.ops = &mmp_clk_reset_ops;
        unit->rcdev.of_node = np;
        unit->rcdev.of_xlate = mmp_of_reset_xlate;

        reset_controller_register(&unit->rcdev);
}