Skip to content

Commit

Permalink
MIPS: ralink: adds clkdev code
Browse files Browse the repository at this point in the history
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/
  • Loading branch information
John Crispin committed Feb 17, 2013
1 parent 7e47cef commit 3f0a06b
Showing 1 changed file with 72 additions and 0 deletions.
72 changes: 72 additions & 0 deletions arch/mips/ralink/clk.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,72 @@
/*
* 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);
}

0 comments on commit 3f0a06b

Please sign in to comment.