mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![Lars-Peter Clausen](/assets/img/avatar_default.png)
The managed clk functions are currently only available when the generic clk lookup framework is build. But the managed clk functions are merely wrappers around clk_get and clk_put and do not depend on any specifics of the generic lookup functions and there are still quite a few custom implementations of the clk API. So make the managed functions available whenever the clk API is implemented. The patch also removes the custom implementation of devm_clk_get for the coldfire platform. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
329 lines
7.4 KiB
C
329 lines
7.4 KiB
C
/*
|
|
* drivers/clk/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 <linux/clk.h>
|
|
#include <linux/clkdev.h>
|
|
#include <linux/of.h>
|
|
|
|
static LIST_HEAD(clocks);
|
|
static DEFINE_MUTEX(clocks_mutex);
|
|
|
|
#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
|
|
struct clk *of_clk_get(struct device_node *np, int index)
|
|
{
|
|
struct of_phandle_args clkspec;
|
|
struct clk *clk;
|
|
int rc;
|
|
|
|
if (index < 0)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index,
|
|
&clkspec);
|
|
if (rc)
|
|
return ERR_PTR(rc);
|
|
|
|
clk = of_clk_get_from_provider(&clkspec);
|
|
of_node_put(clkspec.np);
|
|
return clk;
|
|
}
|
|
EXPORT_SYMBOL(of_clk_get);
|
|
|
|
/**
|
|
* of_clk_get_by_name() - Parse and lookup a clock referenced by a device node
|
|
* @np: pointer to clock consumer node
|
|
* @name: name of consumer's clock input, or NULL for the first clock reference
|
|
*
|
|
* This function parses the clocks and clock-names properties,
|
|
* and uses them to look up the struct clk from the registered list of clock
|
|
* providers.
|
|
*/
|
|
struct clk *of_clk_get_by_name(struct device_node *np, const char *name)
|
|
{
|
|
struct clk *clk = ERR_PTR(-ENOENT);
|
|
|
|
/* Walk up the tree of devices looking for a clock that matches */
|
|
while (np) {
|
|
int index = 0;
|
|
|
|
/*
|
|
* For named clocks, first look up the name in the
|
|
* "clock-names" property. If it cannot be found, then
|
|
* index will be an error code, and of_clk_get() will fail.
|
|
*/
|
|
if (name)
|
|
index = of_property_match_string(np, "clock-names", name);
|
|
clk = of_clk_get(np, index);
|
|
if (!IS_ERR(clk))
|
|
break;
|
|
else if (name && index >= 0) {
|
|
pr_err("ERROR: could not get clock %s:%s(%i)\n",
|
|
np->full_name, name ? name : "", index);
|
|
return clk;
|
|
}
|
|
|
|
/*
|
|
* No matching clock found on this node. If the parent node
|
|
* has a "clock-ranges" property, then we can try one of its
|
|
* clocks.
|
|
*/
|
|
np = np->parent;
|
|
if (np && !of_get_property(np, "clock-ranges", NULL))
|
|
break;
|
|
}
|
|
|
|
return clk;
|
|
}
|
|
EXPORT_SYMBOL(of_clk_get_by_name);
|
|
#endif
|
|
|
|
/*
|
|
* 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 precedence: dev+con > dev only > con only.
|
|
*/
|
|
static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
|
|
{
|
|
struct clk_lookup *p, *cl = NULL;
|
|
int match, best_found = 0, best_possible = 0;
|
|
|
|
if (dev_id)
|
|
best_possible += 2;
|
|
if (con_id)
|
|
best_possible += 1;
|
|
|
|
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 > best_found) {
|
|
cl = p;
|
|
if (match != best_possible)
|
|
best_found = match;
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
return cl;
|
|
}
|
|
|
|
struct clk *clk_get_sys(const char *dev_id, const char *con_id)
|
|
{
|
|
struct clk_lookup *cl;
|
|
|
|
mutex_lock(&clocks_mutex);
|
|
cl = clk_find(dev_id, con_id);
|
|
if (cl && !__clk_get(cl->clk))
|
|
cl = NULL;
|
|
mutex_unlock(&clocks_mutex);
|
|
|
|
return cl ? cl->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;
|
|
struct clk *clk;
|
|
|
|
if (dev) {
|
|
clk = of_clk_get_by_name(dev->of_node, con_id);
|
|
if (!IS_ERR(clk) && __clk_get(clk))
|
|
return clk;
|
|
}
|
|
|
|
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);
|
|
|
|
void __init clkdev_add_table(struct clk_lookup *cl, size_t num)
|
|
{
|
|
mutex_lock(&clocks_mutex);
|
|
while (num--) {
|
|
list_add_tail(&cl->node, &clocks);
|
|
cl++;
|
|
}
|
|
mutex_unlock(&clocks_mutex);
|
|
}
|
|
|
|
#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];
|
|
};
|
|
|
|
static struct clk_lookup * __init_refok
|
|
vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt,
|
|
va_list ap)
|
|
{
|
|
struct clk_lookup_alloc *cla;
|
|
|
|
cla = __clkdev_alloc(sizeof(*cla));
|
|
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) {
|
|
vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
|
|
cla->cl.dev_id = cla->dev_id;
|
|
}
|
|
|
|
return &cla->cl;
|
|
}
|
|
|
|
struct clk_lookup * __init_refok
|
|
clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
|
|
{
|
|
struct clk_lookup *cl;
|
|
va_list ap;
|
|
|
|
va_start(ap, dev_fmt);
|
|
cl = vclkdev_alloc(clk, con_id, dev_fmt, ap);
|
|
va_end(ap);
|
|
|
|
return cl;
|
|
}
|
|
EXPORT_SYMBOL(clkdev_alloc);
|
|
|
|
int clk_add_alias(const char *alias, const char *alias_dev_name, char *id,
|
|
struct device *dev)
|
|
{
|
|
struct clk *r = clk_get(dev, id);
|
|
struct clk_lookup *l;
|
|
|
|
if (IS_ERR(r))
|
|
return PTR_ERR(r);
|
|
|
|
l = clkdev_alloc(r, alias, alias_dev_name);
|
|
clk_put(r);
|
|
if (!l)
|
|
return -ENODEV;
|
|
clkdev_add(l);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(clk_add_alias);
|
|
|
|
/*
|
|
* 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);
|
|
|
|
/**
|
|
* clk_register_clkdev - register one clock lookup for a struct clk
|
|
* @clk: struct clk to associate with all clk_lookups
|
|
* @con_id: connection ID string on device
|
|
* @dev_id: format string describing device name
|
|
*
|
|
* con_id or dev_id may be NULL as a wildcard, just as in the rest of
|
|
* clkdev.
|
|
*
|
|
* To make things easier for mass registration, we detect error clks
|
|
* from a previous clk_register() call, and return the error code for
|
|
* those. This is to permit this function to be called immediately
|
|
* after clk_register().
|
|
*/
|
|
int clk_register_clkdev(struct clk *clk, const char *con_id,
|
|
const char *dev_fmt, ...)
|
|
{
|
|
struct clk_lookup *cl;
|
|
va_list ap;
|
|
|
|
if (IS_ERR(clk))
|
|
return PTR_ERR(clk);
|
|
|
|
va_start(ap, dev_fmt);
|
|
cl = vclkdev_alloc(clk, con_id, dev_fmt, ap);
|
|
va_end(ap);
|
|
|
|
if (!cl)
|
|
return -ENOMEM;
|
|
|
|
clkdev_add(cl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* clk_register_clkdevs - register a set of clk_lookup for a struct clk
|
|
* @clk: struct clk to associate with all clk_lookups
|
|
* @cl: array of clk_lookup structures with con_id and dev_id pre-initialized
|
|
* @num: number of clk_lookup structures to register
|
|
*
|
|
* To make things easier for mass registration, we detect error clks
|
|
* from a previous clk_register() call, and return the error code for
|
|
* those. This is to permit this function to be called immediately
|
|
* after clk_register().
|
|
*/
|
|
int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num)
|
|
{
|
|
unsigned i;
|
|
|
|
if (IS_ERR(clk))
|
|
return PTR_ERR(clk);
|
|
|
|
for (i = 0; i < num; i++, cl++) {
|
|
cl->clk = clk;
|
|
clkdev_add(cl);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(clk_register_clkdevs);
|