drivers/clk/at91/clk-i2s-mux.c

root/drivers/clk/at91/clk-i2s-mux.c
// SPDX-License-Identifier: GPL-2.0
/*
 *  Copyright (C) 2018 Microchip Technology Inc,
 *                     Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
 *
 *
 */

#include <linux/clk-provider.h>
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/slab.h>

#include <soc/at91/atmel-sfr.h>

#include "pmc.h"

struct clk_i2s_mux {
        struct clk_hw hw;
        struct regmap *regmap;
        u8 bus_id;
};

#define to_clk_i2s_mux(hw) container_of(hw, struct clk_i2s_mux, hw)

static u8 clk_i2s_mux_get_parent(struct clk_hw *hw)
{
        struct clk_i2s_mux *mux = to_clk_i2s_mux(hw);
        u32 val;

        regmap_read(mux->regmap, AT91_SFR_I2SCLKSEL, &val);

        return (val & BIT(mux->bus_id)) >> mux->bus_id;
}

static int clk_i2s_mux_set_parent(struct clk_hw *hw, u8 index)
{
        struct clk_i2s_mux *mux = to_clk_i2s_mux(hw);

        return regmap_update_bits(mux->regmap, AT91_SFR_I2SCLKSEL,
                                  BIT(mux->bus_id), index << mux->bus_id);
}

static const struct clk_ops clk_i2s_mux_ops = {
        .get_parent = clk_i2s_mux_get_parent,
        .set_parent = clk_i2s_mux_set_parent,
        .determine_rate = __clk_mux_determine_rate,
};

struct clk_hw * __init
at91_clk_i2s_mux_register(struct regmap *regmap, const char *name,
                          const char * const *parent_names,
                          unsigned int num_parents, u8 bus_id)
{
        struct clk_init_data init = {};
        struct clk_i2s_mux *i2s_ck;
        int ret;

        i2s_ck = kzalloc_obj(*i2s_ck);
        if (!i2s_ck)
                return ERR_PTR(-ENOMEM);

        init.name = name;
        init.ops = &clk_i2s_mux_ops;
        init.parent_names = parent_names;
        init.num_parents = num_parents;

        i2s_ck->hw.init = &init;
        i2s_ck->bus_id = bus_id;
        i2s_ck->regmap = regmap;

        ret = clk_hw_register(NULL, &i2s_ck->hw);
        if (ret) {
                kfree(i2s_ck);
                return ERR_PTR(ret);
        }

        return &i2s_ck->hw;
}
Linux
