forked from luck/tmp_suning_uos_patched
05fd8e73e1
This adds clk_get_sys to get a clock without the associated struct device. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
149 lines
3.1 KiB
C
149 lines
3.1 KiB
C
/*
|
|
* arch/arm/common/clkdev.c
|
|
*
|
|
* Copyright (C) 2008 Russell King.
|
|
*
|
|
* 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.
|
|
*
|
|
* Helper for the clk API to assist looking up a struct clk.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/device.h>
|
|
#include <linux/list.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/err.h>
|
|
#include <linux/string.h>
|
|
#include <linux/mutex.h>
|
|
|
|
#include <asm/clkdev.h>
|
|
#include <mach/clkdev.h>
|
|
|
|
static LIST_HEAD(clocks);
|
|
static DEFINE_MUTEX(clocks_mutex);
|
|
|
|
/*
|
|
* Find the correct struct clk for the device and connection ID.
|
|
* We do slightly fuzzy matching here:
|
|
* An entry with a NULL ID is assumed to be a wildcard.
|
|
* If an entry has a device ID, it must match
|
|
* If an entry has a connection ID, it must match
|
|
* Then we take the most specific entry - with the following
|
|
* order of precidence: dev+con > dev only > con only.
|
|
*/
|
|
static struct clk *clk_find(const char *dev_id, const char *con_id)
|
|
{
|
|
struct clk_lookup *p;
|
|
struct clk *clk = NULL;
|
|
int match, best = 0;
|
|
|
|
list_for_each_entry(p, &clocks, node) {
|
|
match = 0;
|
|
if (p->dev_id) {
|
|
if (!dev_id || strcmp(p->dev_id, dev_id))
|
|
continue;
|
|
match += 2;
|
|
}
|
|
if (p->con_id) {
|
|
if (!con_id || strcmp(p->con_id, con_id))
|
|
continue;
|
|
match += 1;
|
|
}
|
|
if (match == 0)
|
|
continue;
|
|
|
|
if (match > best) {
|
|
clk = p->clk;
|
|
best = match;
|
|
}
|
|
}
|
|
return clk;
|
|
}
|
|
|
|
struct clk *clk_get_sys(const char *dev_id, const char *con_id)
|
|
{
|
|
struct clk *clk;
|
|
|
|
mutex_lock(&clocks_mutex);
|
|
clk = clk_find(dev_id, con_id);
|
|
if (clk && !__clk_get(clk))
|
|
clk = NULL;
|
|
mutex_unlock(&clocks_mutex);
|
|
|
|
return clk ? clk : ERR_PTR(-ENOENT);
|
|
}
|
|
EXPORT_SYMBOL(clk_get_sys);
|
|
|
|
struct clk *clk_get(struct device *dev, const char *con_id)
|
|
{
|
|
const char *dev_id = dev ? dev_name(dev) : NULL;
|
|
|
|
return clk_get_sys(dev_id, con_id);
|
|
}
|
|
EXPORT_SYMBOL(clk_get);
|
|
|
|
void clk_put(struct clk *clk)
|
|
{
|
|
__clk_put(clk);
|
|
}
|
|
EXPORT_SYMBOL(clk_put);
|
|
|
|
void clkdev_add(struct clk_lookup *cl)
|
|
{
|
|
mutex_lock(&clocks_mutex);
|
|
list_add_tail(&cl->node, &clocks);
|
|
mutex_unlock(&clocks_mutex);
|
|
}
|
|
EXPORT_SYMBOL(clkdev_add);
|
|
|
|
#define MAX_DEV_ID 20
|
|
#define MAX_CON_ID 16
|
|
|
|
struct clk_lookup_alloc {
|
|
struct clk_lookup cl;
|
|
char dev_id[MAX_DEV_ID];
|
|
char con_id[MAX_CON_ID];
|
|
};
|
|
|
|
struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,
|
|
const char *dev_fmt, ...)
|
|
{
|
|
struct clk_lookup_alloc *cla;
|
|
|
|
cla = kzalloc(sizeof(*cla), GFP_KERNEL);
|
|
if (!cla)
|
|
return NULL;
|
|
|
|
cla->cl.clk = clk;
|
|
if (con_id) {
|
|
strlcpy(cla->con_id, con_id, sizeof(cla->con_id));
|
|
cla->cl.con_id = cla->con_id;
|
|
}
|
|
|
|
if (dev_fmt) {
|
|
va_list ap;
|
|
|
|
va_start(ap, dev_fmt);
|
|
vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
|
|
cla->cl.dev_id = cla->dev_id;
|
|
va_end(ap);
|
|
}
|
|
|
|
return &cla->cl;
|
|
}
|
|
EXPORT_SYMBOL(clkdev_alloc);
|
|
|
|
/*
|
|
* clkdev_drop - remove a clock dynamically allocated
|
|
*/
|
|
void clkdev_drop(struct clk_lookup *cl)
|
|
{
|
|
mutex_lock(&clocks_mutex);
|
|
list_del(&cl->node);
|
|
mutex_unlock(&clocks_mutex);
|
|
kfree(cl);
|
|
}
|
|
EXPORT_SYMBOL(clkdev_drop);
|