android_kernel_xiaomi_sm8350/arch/arm/mach-pxa/clock.c
Russell King bdb08cb2d3 [ARM] pxa: allow clk aliases
We need to support more than one name+device for a struct clk for a
small number of peripherals.  We do this by re-using struct clk alias
to another struct clk - IOW, if we find that the entry we're using is
an alias, we return the aliased entry not the one we found.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-09 20:54:14 +01:00

158 lines
2.8 KiB
C

/*
* 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 <linux/platform_device.h>
#include <linux/delay.h>
#include <asm/arch/pxa-regs.h>
#include <asm/arch/pxa2xx-gpio.h>
#include <asm/hardware.h>
#include "devices.h"
#include "generic.h"
#include "clock.h"
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
static DEFINE_SPINLOCK(clocks_lock);
static struct clk *clk_lookup(struct device *dev, const char *id)
{
struct clk *p;
list_for_each_entry(p, &clocks, node)
if (strcmp(id, p->name) == 0 && p->dev == dev)
return p;
return NULL;
}
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *p, *clk = ERR_PTR(-ENOENT);
mutex_lock(&clocks_mutex);
p = clk_lookup(dev, id);
if (!p)
p = clk_lookup(NULL, id);
if (p)
clk = p;
mutex_unlock(&clocks_mutex);
if (!IS_ERR(clk) && clk->ops == NULL)
clk = clk->other;
return clk;
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_put);
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clocks_lock, flags);
if (clk->enabled++ == 0)
clk->ops->enable(clk);
spin_unlock_irqrestore(&clocks_lock, flags);
if (clk->delay)
udelay(clk->delay);
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->ops->disable(clk);
spin_unlock_irqrestore(&clocks_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
unsigned long rate;
rate = clk->rate;
if (clk->ops->getrate)
rate = clk->ops->getrate(clk);
return rate;
}
EXPORT_SYMBOL(clk_get_rate);
static void clk_gpio27_enable(struct clk *clk)
{
pxa_gpio_mode(GPIO11_3_6MHz_MD);
}
static void clk_gpio27_disable(struct clk *clk)
{
}
static const struct clkops clk_gpio27_ops = {
.enable = clk_gpio27_enable,
.disable = clk_gpio27_disable,
};
void clk_cken_enable(struct clk *clk)
{
CKEN |= 1 << clk->cken;
}
void clk_cken_disable(struct clk *clk)
{
CKEN &= ~(1 << clk->cken);
}
const struct clkops clk_cken_ops = {
.enable = clk_cken_enable,
.disable = clk_cken_disable,
};
static struct clk common_clks[] = {
{
.name = "GPIO27_CLK",
.ops = &clk_gpio27_ops,
.rate = 3686400,
},
};
void clks_register(struct clk *clks, size_t num)
{
int i;
mutex_lock(&clocks_mutex);
for (i = 0; i < num; i++)
list_add(&clks[i].node, &clocks);
mutex_unlock(&clocks_mutex);
}
static int __init clk_init(void)
{
clks_register(common_clks, ARRAY_SIZE(common_clks));
return 0;
}
arch_initcall(clk_init);