acrn-kernel/arch/avr32/mach-at32ap/clock.c

149 lines
2.9 KiB
C

/*
* Clock management for AT32AP CPUs
*
* Copyright (C) 2006 Atmel Corporation
*
* Based on arch/arm/mach-at91rm9200/clock.c
* Copyright (C) 2005 David Brownell
* Copyright (C) 2005 Ivan Kokshaysky
*
* 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/clk.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/string.h>
#include "clock.h"
static spinlock_t clk_lock = SPIN_LOCK_UNLOCKED;
struct clk *clk_get(struct device *dev, const char *id)
{
int i;
for (i = 0; i < at32_nr_clocks; i++) {
struct clk *clk = at32_clock_list[i];
if (clk->dev == dev && strcmp(id, clk->name) == 0)
return clk;
}
return ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
/* clocks are static for now, we can't free them */
}
EXPORT_SYMBOL(clk_put);
static void __clk_enable(struct clk *clk)
{
if (clk->parent)
__clk_enable(clk->parent);
if (clk->users++ == 0 && clk->mode)
clk->mode(clk, 1);
}
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clk_lock, flags);
__clk_enable(clk);
spin_unlock_irqrestore(&clk_lock, flags);
return 0;
}
EXPORT_SYMBOL(clk_enable);
static void __clk_disable(struct clk *clk)
{
BUG_ON(clk->users == 0);
if (--clk->users == 0 && clk->mode)
clk->mode(clk, 0);
if (clk->parent)
__clk_disable(clk->parent);
}
void clk_disable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clk_lock, flags);
__clk_disable(clk);
spin_unlock_irqrestore(&clk_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
unsigned long flags;
unsigned long rate;
spin_lock_irqsave(&clk_lock, flags);
rate = clk->get_rate(clk);
spin_unlock_irqrestore(&clk_lock, flags);
return rate;
}
EXPORT_SYMBOL(clk_get_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags, actual_rate;
if (!clk->set_rate)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
actual_rate = clk->set_rate(clk, rate, 0);
spin_unlock_irqrestore(&clk_lock, flags);
return actual_rate;
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags;
long ret;
if (!clk->set_rate)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
ret = clk->set_rate(clk, rate, 1);
spin_unlock_irqrestore(&clk_lock, flags);
return (ret < 0) ? ret : 0;
}
EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
unsigned long flags;
int ret;
if (!clk->set_parent)
return -ENOSYS;
spin_lock_irqsave(&clk_lock, flags);
ret = clk->set_parent(clk, parent);
spin_unlock_irqrestore(&clk_lock, flags);
return ret;
}
EXPORT_SYMBOL(clk_set_parent);
struct clk *clk_get_parent(struct clk *clk)
{
return clk->parent;
}
EXPORT_SYMBOL(clk_get_parent);