drivers/clk/rockchip/clk-muxgrf.c

root/drivers/clk/rockchip/clk-muxgrf.c
// SPDX-License-Identifier: GPL-2.0-only

#include <linux/slab.h>
#include <linux/bitops.h>
#include <linux/regmap.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include "clk.h"

struct rockchip_muxgrf_clock {
        struct clk_hw           hw;
        struct regmap           *regmap;
        u32                     reg;
        u32                     shift;
        u32                     width;
        int                     flags;
};

#define to_muxgrf_clock(_hw) container_of(_hw, struct rockchip_muxgrf_clock, hw)

static u8 rockchip_muxgrf_get_parent(struct clk_hw *hw)
{
        struct rockchip_muxgrf_clock *mux = to_muxgrf_clock(hw);
        unsigned int mask = GENMASK(mux->width - 1, 0);
        unsigned int val;

        regmap_read(mux->regmap, mux->reg, &val);

        val >>= mux->shift;
        val &= mask;

        return val;
}

static int rockchip_muxgrf_set_parent(struct clk_hw *hw, u8 index)
{
        struct rockchip_muxgrf_clock *mux = to_muxgrf_clock(hw);
        unsigned int mask = GENMASK(mux->width + mux->shift - 1, mux->shift);
        unsigned int val;

        val = index;
        val <<= mux->shift;

        if (mux->flags & CLK_MUX_HIWORD_MASK)
                return regmap_write(mux->regmap, mux->reg, val | (mask << 16));
        else
                return regmap_update_bits(mux->regmap, mux->reg, mask, val);
}

static const struct clk_ops rockchip_muxgrf_clk_ops = {
        .get_parent = rockchip_muxgrf_get_parent,
        .set_parent = rockchip_muxgrf_set_parent,
        .determine_rate = __clk_mux_determine_rate,
};

struct clk *rockchip_clk_register_muxgrf(const char *name,
                                const char *const *parent_names, u8 num_parents,
                                int flags, struct regmap *regmap, int reg,
                                int shift, int width, int mux_flags)
{
        struct rockchip_muxgrf_clock *muxgrf_clock;
        struct clk_init_data init;
        struct clk *clk;

        if (IS_ERR(regmap)) {
                pr_err("%s: regmap not available\n", __func__);
                return ERR_PTR(-ENOTSUPP);
        }

        muxgrf_clock = kmalloc_obj(*muxgrf_clock);
        if (!muxgrf_clock)
                return ERR_PTR(-ENOMEM);

        init.name = name;
        init.flags = flags;
        init.num_parents = num_parents;
        init.parent_names = parent_names;
        init.ops = &rockchip_muxgrf_clk_ops;

        muxgrf_clock->hw.init = &init;
        muxgrf_clock->regmap = regmap;
        muxgrf_clock->reg = reg;
        muxgrf_clock->shift = shift;
        muxgrf_clock->width = width;
        muxgrf_clock->flags = mux_flags;

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

        return clk;
}
Linux
