clk.h

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/*
 *  linux/include/linux/clk.h
 *
 *  Copyright (C) 2004 ARM Limited.
 *  Written by Deep Blue Solutions Limited.
 *  Copyright (C) 2011-2012 Linaro Ltd <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef __LINUX_CLK_H
#define __LINUX_CLK_H

#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/notifier.h>

struct device;

struct clk;

#ifdef CONFIG_COMMON_CLK

#define PRE_RATE_CHANGE         BIT(0)
#define POST_RATE_CHANGE        BIT(1)
#define ABORT_RATE_CHANGE       BIT(2)

struct clk_notifier {
    struct clk          *clk;
    struct srcu_notifier_head   notifier_head;
    struct list_head        node;
};

struct clk_notifier_data {
    struct clk      *clk;
    unsigned long       old_rate;
    unsigned long       new_rate;
};

int clk_notifier_register(struct clk *clk, struct notifier_block *nb);

int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb);

#endif

#ifdef CONFIG_HAVE_CLK_PREPARE
int clk_prepare(struct clk *clk);
#else
static inline int clk_prepare(struct clk *clk)
{
    might_sleep();
    return 0;
}
#endif

#ifdef CONFIG_HAVE_CLK_PREPARE
void clk_unprepare(struct clk *clk);
#else
static inline void clk_unprepare(struct clk *clk)
{
    might_sleep();
}
#endif

#ifdef CONFIG_HAVE_CLK

struct clk *clk_get(struct device *dev, const char *id);

struct clk *devm_clk_get(struct device *dev, const char *id);

int clk_enable(struct clk *clk);

void clk_disable(struct clk *clk);

unsigned long clk_get_rate(struct clk *clk);

void clk_put(struct clk *clk);

void devm_clk_put(struct device *dev, struct clk *clk);

/*
 * The remaining APIs are optional for machine class support.
 */


long clk_round_rate(struct clk *clk, unsigned long rate);

int clk_set_rate(struct clk *clk, unsigned long rate);

int clk_set_parent(struct clk *clk, struct clk *parent);

struct clk *clk_get_parent(struct clk *clk);

struct clk *clk_get_sys(const char *dev_id, const char *con_id);

#else /* !CONFIG_HAVE_CLK */

static inline struct clk *clk_get(struct device *dev, const char *id)
{
    return NULL;
}

static inline struct clk *devm_clk_get(struct device *dev, const char *id)
{
    return NULL;
}

static inline void clk_put(struct clk *clk) {}

static inline void devm_clk_put(struct device *dev, struct clk *clk) {}

static inline int clk_enable(struct clk *clk)
{
    return 0;
}

static inline void clk_disable(struct clk *clk) {}

static inline unsigned long clk_get_rate(struct clk *clk)
{
    return 0;
}

static inline int clk_set_rate(struct clk *clk, unsigned long rate)
{
    return 0;
}

static inline long clk_round_rate(struct clk *clk, unsigned long rate)
{
    return 0;
}

static inline int clk_set_parent(struct clk *clk, struct clk *parent)
{
    return 0;
}

static inline struct clk *clk_get_parent(struct clk *clk)
{
    return NULL;
}

#endif

/* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
static inline int clk_prepare_enable(struct clk *clk)
{
    int ret;

    ret = clk_prepare(clk);
    if (ret)
        return ret;
    ret = clk_enable(clk);
    if (ret)
        clk_unprepare(clk);

    return ret;
}

/* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */
static inline void clk_disable_unprepare(struct clk *clk)
{
    clk_disable(clk);
    clk_unprepare(clk);
}

int clk_add_alias(const char *alias, const char *alias_dev_name, char *id,
            struct device *dev);

struct device_node;
struct of_phandle_args;

#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
struct clk *of_clk_get(struct device_node *np, int index);
struct clk *of_clk_get_by_name(struct device_node *np, const char *name);
struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec);
#else
static inline struct clk *of_clk_get(struct device_node *np, int index)
{
    return ERR_PTR(-ENOENT);
}
static inline struct clk *of_clk_get_by_name(struct device_node *np,
                         const char *name)
{
    return ERR_PTR(-ENOENT);
}
#endif

#endif