clk.c

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/***************************************************************************/

/*
 *  clk.c -- general ColdFire CPU kernel clk handling
 *
 *  Copyright (C) 2009, Greg Ungerer ([email protected])
 */

/***************************************************************************/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/err.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/mcfclk.h>

/***************************************************************************/
#ifndef MCFPM_PPMCR0
struct clk *clk_get(struct device *dev, const char *id)
{
    return NULL;
}
EXPORT_SYMBOL(clk_get);

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

void clk_disable(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_disable);

void clk_put(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_put);

unsigned long clk_get_rate(struct clk *clk)
{
    return MCF_CLK;
}
EXPORT_SYMBOL(clk_get_rate);
#else
static DEFINE_SPINLOCK(clk_lock);

struct clk *clk_get(struct device *dev, const char *id)
{
    const char *clk_name = dev ? dev_name(dev) : id ? id : NULL;
    struct clk *clk;
    unsigned i;

    for (i = 0; (clk = mcf_clks[i]) != NULL; ++i)
        if (!strcmp(clk->name, clk_name))
            return clk;
    pr_warn("clk_get: didn't find clock %s\n", clk_name);
    return ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get);

int clk_enable(struct clk *clk)
{
    unsigned long flags;
    spin_lock_irqsave(&clk_lock, flags);
    if ((clk->enabled++ == 0) && clk->clk_ops)
        clk->clk_ops->enable(clk);
    spin_unlock_irqrestore(&clk_lock, flags);

    return 0;
}
EXPORT_SYMBOL(clk_enable);

void clk_disable(struct clk *clk)
{
    unsigned long flags;
    spin_lock_irqsave(&clk_lock, flags);
    if ((--clk->enabled == 0) && clk->clk_ops)
        clk->clk_ops->disable(clk);
    spin_unlock_irqrestore(&clk_lock, flags);
}
EXPORT_SYMBOL(clk_disable);

void clk_put(struct clk *clk)
{
    if (clk->enabled != 0)
        pr_warn("clk_put %s still enabled\n", clk->name);
}
EXPORT_SYMBOL(clk_put);

unsigned long clk_get_rate(struct clk *clk)
{
    return clk->rate;
}
EXPORT_SYMBOL(clk_get_rate);

/***************************************************************************/

void __clk_init_enabled(struct clk *clk)
{
    clk->enabled = 1;
    clk->clk_ops->enable(clk);
}

void __clk_init_disabled(struct clk *clk)
{
    clk->enabled = 0;
    clk->clk_ops->disable(clk);
}

static void __clk_enable0(struct clk *clk)
{
    __raw_writeb(clk->slot, MCFPM_PPMCR0);
}

static void __clk_disable0(struct clk *clk)
{
    __raw_writeb(clk->slot, MCFPM_PPMSR0);
}

struct clk_ops clk_ops0 = {
    .enable     = __clk_enable0,
    .disable    = __clk_disable0,
};

#ifdef MCFPM_PPMCR1
static void __clk_enable1(struct clk *clk)
{
    __raw_writeb(clk->slot, MCFPM_PPMCR1);
}

static void __clk_disable1(struct clk *clk)
{
    __raw_writeb(clk->slot, MCFPM_PPMSR1);
}

struct clk_ops clk_ops1 = {
    .enable     = __clk_enable1,
    .disable    = __clk_disable1,
};
#endif /* MCFPM_PPMCR1 */
#endif /* MCFPM_PPMCR0 */