linux/arch/arm/mach-w90x900/clock.c
Arnd Bergmann bd7fefe1f0 ARM: w90x900: normalize clk API
w90x900 still provides its own variant of the clk API rather than using
the generic COMMON_CLK API. This generally works, but it causes some link
errors with drivers using the clk_set_rate, clk_get_parent, clk_set_parent
or clk_round_rate functions when a platform lacks those interfaces.

This adds empty stub implementations for each of them, and I don't even
try to do something useful here but instead just print a WARN() message
to make it obvious what is going on if they ever end up being called.

The drivers that call these won't be used on these platforms (otherwise
we'd get a link error today), so the added code is harmless bloat and
will warn about accidental use.

A while ago there was a proposal to change w90x900 to use the common-clk
implementation, which would be the way it should be handled properly.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2017-07-27 22:57:36 +02:00

125 lines
2.3 KiB
C

/*
* linux/arch/arm/mach-w90x900/clock.c
*
* Copyright (c) 2008 Nuvoton technology corporation
*
* Wan ZongShun <mcuos.com@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*/
#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 <linux/platform_device.h>
#include <linux/io.h>
#include <mach/hardware.h>
#include "clock.h"
#define SUBCLK 0x24
static DEFINE_SPINLOCK(clocks_lock);
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clocks_lock, flags);
if (clk->enabled++ == 0)
(clk->enable)(clk, 1);
spin_unlock_irqrestore(&clocks_lock, flags);
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
unsigned long flags;
if (!clk)
return;
WARN_ON(clk->enabled == 0);
spin_lock_irqsave(&clocks_lock, flags);
if (--clk->enabled == 0)
(clk->enable)(clk, 0);
spin_unlock_irqrestore(&clocks_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return 15000000;
}
EXPORT_SYMBOL(clk_get_rate);
void nuc900_clk_enable(struct clk *clk, int enable)
{
unsigned int clocks = clk->cken;
unsigned long clken;
clken = __raw_readl(W90X900_VA_CLKPWR);
if (enable)
clken |= clocks;
else
clken &= ~clocks;
__raw_writel(clken, W90X900_VA_CLKPWR);
}
void nuc900_subclk_enable(struct clk *clk, int enable)
{
unsigned int clocks = clk->cken;
unsigned long clken;
clken = __raw_readl(W90X900_VA_CLKPWR + SUBCLK);
if (enable)
clken |= clocks;
else
clken &= ~clocks;
__raw_writel(clken, W90X900_VA_CLKPWR + SUBCLK);
}
/* dummy functions, should not be called */
long clk_round_rate(struct clk *clk, unsigned long rate)
{
WARN_ON(clk);
return 0;
}
EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
WARN_ON(clk);
return 0;
}
EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
WARN_ON(clk);
return 0;
}
EXPORT_SYMBOL(clk_set_parent);
struct clk *clk_get_parent(struct clk *clk)
{
WARN_ON(clk);
return NULL;
}
EXPORT_SYMBOL(clk_get_parent);