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/*
* linux/arch/arm/mach-sa1100/clock.c
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include <asm/arch/pxa-regs.h>
#include <asm/hardware.h>
#include <asm/semaphore.h>
struct clk {
struct list_head node;
unsigned long rate;
struct module *owner;
const char *name;
unsigned int enabled;
void (*enable)(void);
void (*disable)(void);
};
static LIST_HEAD(clocks);
static DECLARE_MUTEX(clocks_sem);
static DEFINE_SPINLOCK(clocks_lock);
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *p, *clk = ERR_PTR(-ENOENT);
down(&clocks_sem);
list_for_each_entry(p, &clocks, node) {
if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
clk = p;
break;
}
}
up(&clocks_sem);
return clk;
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
module_put(clk->owner);
}
EXPORT_SYMBOL(clk_put);
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clocks_lock, flags);
if (clk->enabled++ == 0)
clk->enable();
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->disable();
spin_unlock_irqrestore(&clocks_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return clk->rate;
}
EXPORT_SYMBOL(clk_get_rate);
static void clk_gpio27_enable(void)
{
pxa_gpio_mode(GPIO11_3_6MHz_MD);
}
static void clk_gpio27_disable(void)
{
}
static struct clk clk_gpio27 = {
.name = "GPIO27_CLK",
.rate = 3686400,
.enable = clk_gpio27_enable,
.disable = clk_gpio27_disable,
};
int clk_register(struct clk *clk)
{
down(&clocks_sem);
list_add(&clk->node, &clocks);
up(&clocks_sem);
return 0;
}
EXPORT_SYMBOL(clk_register);
void clk_unregister(struct clk *clk)
{
down(&clocks_sem);
list_del(&clk->node);
up(&clocks_sem);
}
EXPORT_SYMBOL(clk_unregister);
static int __init clk_init(void)
{
clk_register(&clk_gpio27);
return 0;
}
arch_initcall(clk_init);
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