MIPS: ralink: adds clkdev code

These SoCs have a limited number of fixed rate clocks. Add support for the
clk and clkdev api.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4894/
This commit is contained in:
John Crispin 2013-01-20 22:01:29 +01:00
parent 7e47cefa69
commit 3f0a06b036

72
arch/mips/ralink/clk.c Normal file
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/*
* 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.
*
* Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/clkdev.h>
#include <linux/clk.h>
#include <asm/time.h>
#include "common.h"
struct clk {
struct clk_lookup cl;
unsigned long rate;
};
void ralink_clk_add(const char *dev, unsigned long rate)
{
struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
if (!clk)
panic("failed to add clock\n");
clk->cl.dev_id = dev;
clk->cl.clk = clk;
clk->rate = rate;
clkdev_add(&clk->cl);
}
/*
* Linux clock API
*/
int clk_enable(struct clk *clk)
{
return 0;
}
EXPORT_SYMBOL_GPL(clk_enable);
void clk_disable(struct clk *clk)
{
}
EXPORT_SYMBOL_GPL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return clk->rate;
}
EXPORT_SYMBOL_GPL(clk_get_rate);
void __init plat_time_init(void)
{
struct clk *clk;
ralink_of_remap();
ralink_clk_init();
clk = clk_get_sys("cpu", NULL);
if (IS_ERR(clk))
panic("unable to get CPU clock, err=%ld", PTR_ERR(clk));
pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);
mips_hpt_frequency = clk_get_rate(clk) / 2;
clk_put(clk);
}