clock.c

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/*
 *  linux/arch/arm/mach-mmp/clock.c
 *
 *  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.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/clk.h>
#include <linux/io.h>

#include <mach/regs-apbc.h>
#include "clock.h"

static void apbc_clk_enable(struct clk *clk)
{
    uint32_t clk_rst;

    clk_rst = APBC_APBCLK | APBC_FNCLK | APBC_FNCLKSEL(clk->fnclksel);
    __raw_writel(clk_rst, clk->clk_rst);
}

static void apbc_clk_disable(struct clk *clk)
{
    __raw_writel(0, clk->clk_rst);
}

struct clkops apbc_clk_ops = {
    .enable     = apbc_clk_enable,
    .disable    = apbc_clk_disable,
};

static void apmu_clk_enable(struct clk *clk)
{
    __raw_writel(clk->enable_val, clk->clk_rst);
}

static void apmu_clk_disable(struct clk *clk)
{
    __raw_writel(0, clk->clk_rst);
}

struct clkops apmu_clk_ops = {
    .enable     = apmu_clk_enable,
    .disable    = apmu_clk_disable,
};

static DEFINE_SPINLOCK(clocks_lock);

int clk_enable(struct clk *clk)
{
    unsigned long flags;

    spin_lock_irqsave(&clocks_lock, flags);
    if (clk->enabled++ == 0)
        clk->ops->enable(clk);
    spin_unlock_irqrestore(&clocks_lock, flags);
    return 0;
}
EXPORT_SYMBOL(clk_enable);

void clk_disable(struct clk *clk)
{
    unsigned long flags;

    WARN_ON(clk->enabled == 0);

    spin_lock_irqsave(&clocks_lock, flags);
    if (--clk->enabled == 0)
        clk->ops->disable(clk);
    spin_unlock_irqrestore(&clocks_lock, flags);
}
EXPORT_SYMBOL(clk_disable);

unsigned long clk_get_rate(struct clk *clk)
{
    unsigned long rate;

    if (clk->ops->getrate)
        rate = clk->ops->getrate(clk);
    else
        rate = clk->rate;

    return rate;
}
EXPORT_SYMBOL(clk_get_rate);

int clk_set_rate(struct clk *clk, unsigned long rate)
{
    unsigned long flags;
    int ret = -EINVAL;

    if (clk->ops->setrate) {
        spin_lock_irqsave(&clocks_lock, flags);
        ret = clk->ops->setrate(clk, rate);
        spin_unlock_irqrestore(&clocks_lock, flags);
    }

    return ret;
}
EXPORT_SYMBOL(clk_set_rate);