sh: clock framework update, fix count and kill off kref
This patch updates the clock framework use count code.
With this patch the enable() and disable() callbacks
only get called when counting from and to zero.
While at it the kref stuff gets replaced with an int.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/cpu/clock.c b/arch/sh/kernel/cpu/clock.c
index 099373a..133dbe4 100644
--- a/arch/sh/kernel/cpu/clock.c
+++ b/arch/sh/kernel/cpu/clock.c
@@ -19,7 +19,6 @@
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/list.h>
-#include <linux/kref.h>
#include <linux/kobject.h>
#include <linux/sysdev.h>
#include <linux/seq_file.h>
@@ -90,7 +89,7 @@
}
}
-static int __clk_enable(struct clk *clk)
+static void __clk_init(struct clk *clk)
{
/*
* See if this is the first time we're enabling the clock, some
@@ -100,19 +99,33 @@
* divisors to use before it can effectively recalc.
*/
- if (clk->flags & CLK_ALWAYS_ENABLED) {
- kref_get(&clk->kref);
- return 0;
- }
-
- if (unlikely(atomic_read(&clk->kref.refcount) == 1))
+ if (clk->flags & CLK_NEEDS_INIT) {
if (clk->ops && clk->ops->init)
clk->ops->init(clk);
- kref_get(&clk->kref);
+ clk->flags &= ~CLK_NEEDS_INIT;
+ }
+}
- if (likely(clk->ops && clk->ops->enable))
- clk->ops->enable(clk);
+static int __clk_enable(struct clk *clk)
+{
+ if (!clk)
+ return -EINVAL;
+
+ clk->usecount++;
+
+ /* nothing to do if always enabled */
+ if (clk->flags & CLK_ALWAYS_ENABLED)
+ return 0;
+
+ if (clk->usecount == 1) {
+ __clk_init(clk);
+
+ __clk_enable(clk->parent);
+
+ if (clk->ops && clk->ops->enable)
+ clk->ops->enable(clk);
+ }
return 0;
}
@@ -122,11 +135,6 @@
unsigned long flags;
int ret;
- if (!clk)
- return -EINVAL;
-
- clk_enable(clk->parent);
-
spin_lock_irqsave(&clock_lock, flags);
ret = __clk_enable(clk);
spin_unlock_irqrestore(&clock_lock, flags);
@@ -135,21 +143,23 @@
}
EXPORT_SYMBOL_GPL(clk_enable);
-static void clk_kref_release(struct kref *kref)
-{
- /* Nothing to do */
-}
-
static void __clk_disable(struct clk *clk)
{
- int count = kref_put(&clk->kref, clk_kref_release);
+ if (!clk)
+ return;
+
+ clk->usecount--;
+
+ WARN_ON(clk->usecount < 0);
if (clk->flags & CLK_ALWAYS_ENABLED)
return;
- if (!count) { /* count reaches zero, disable the clock */
+ if (clk->usecount == 0) {
if (likely(clk->ops && clk->ops->disable))
clk->ops->disable(clk);
+
+ __clk_disable(clk->parent);
}
}
@@ -157,14 +167,9 @@
{
unsigned long flags;
- if (!clk)
- return;
-
spin_lock_irqsave(&clock_lock, flags);
__clk_disable(clk);
spin_unlock_irqrestore(&clock_lock, flags);
-
- clk_disable(clk->parent);
}
EXPORT_SYMBOL_GPL(clk_disable);
@@ -173,14 +178,14 @@
mutex_lock(&clock_list_sem);
list_add(&clk->node, &clock_list);
- kref_init(&clk->kref);
+ clk->usecount = 0;
+ clk->flags |= CLK_NEEDS_INIT;
mutex_unlock(&clock_list_sem);
if (clk->flags & CLK_ALWAYS_ENABLED) {
+ __clk_init(clk);
pr_debug( "Clock '%s' is ALWAYS_ENABLED\n", clk->name);
- if (clk->ops && clk->ops->init)
- clk->ops->init(clk);
if (clk->ops && clk->ops->enable)
clk->ops->enable(clk);
pr_debug( "Enabled.");
@@ -356,7 +361,7 @@
p += sprintf(p, "%-12s\t: %ld.%02ldMHz\t%s\n", clk->name,
rate / 1000000, (rate % 1000000) / 10000,
((clk->flags & CLK_ALWAYS_ENABLED) ||
- (atomic_read(&clk->kref.refcount) != 1)) ?
+ clk->usecount > 0) ?
"enabled" : "disabled");
}