linux/arch/arm/mach-versatile/clock.c

146 lines
2.5 KiB
C

/*
* linux/arch/arm/mach-versatile/clock.c
*
* Copyright (C) 2004 ARM Limited.
* Written by Deep Blue Solutions Limited.
*
* 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/errno.h>
#include <linux/err.h>
#include <asm/semaphore.h>
#include <asm/hardware/clock.h>
#include <asm/hardware/icst307.h>
#include "clock.h"
static LIST_HEAD(clocks);
static DECLARE_MUTEX(clocks_sem);
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)
{
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_disable);
int clk_use(struct clk *clk)
{
return 0;
}
EXPORT_SYMBOL(clk_use);
void clk_unuse(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_unuse);
unsigned long clk_get_rate(struct clk *clk)
{
return clk->rate;
}
EXPORT_SYMBOL(clk_get_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
return rate;
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
int ret = -EIO;
if (clk->setvco) {
struct icst307_vco vco;
vco = icst307_khz_to_vco(clk->params, rate / 1000);
clk->rate = icst307_khz(clk->params, vco) * 1000;
printk("Clock %s: setting VCO reg params: S=%d R=%d V=%d\n",
clk->name, vco.s, vco.r, vco.v);
clk->setvco(clk, vco);
ret = 0;
}
return ret;
}
EXPORT_SYMBOL(clk_set_rate);
/*
* These are fixed clocks.
*/
static struct clk kmi_clk = {
.name = "KMIREFCLK",
.rate = 24000000,
};
static struct clk uart_clk = {
.name = "UARTCLK",
.rate = 24000000,
};
static struct clk mmci_clk = {
.name = "MCLK",
.rate = 33000000,
};
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(&kmi_clk);
clk_register(&uart_clk);
clk_register(&mmci_clk);
return 0;
}
arch_initcall(clk_init);