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path: root/arch/arm/plat-omap/clock.c
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Diffstat (limited to 'arch/arm/plat-omap/clock.c')
-rw-r--r--arch/arm/plat-omap/clock.c68
1 files changed, 66 insertions, 2 deletions
diff --git a/arch/arm/plat-omap/clock.c b/arch/arm/plat-omap/clock.c
index 3c2bfc0efda..32ec04c58bc 100644
--- a/arch/arm/plat-omap/clock.c
+++ b/arch/arm/plat-omap/clock.c
@@ -21,6 +21,7 @@
#include <linux/string.h>
#include <linux/clk.h>
#include <linux/mutex.h>
+#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/semaphore.h>
@@ -37,17 +38,38 @@ static struct clk_functions *arch_clock;
* Standard clock functions defined in include/linux/clk.h
*-------------------------------------------------------------------------*/
+/*
+ * Returns a clock. Note that we first try to use device id on the bus
+ * and clock name. If this fails, we try to use clock name only.
+ */
struct clk * clk_get(struct device *dev, const char *id)
{
struct clk *p, *clk = ERR_PTR(-ENOENT);
+ int idno;
+
+ if (dev == NULL || dev->bus != &platform_bus_type)
+ idno = -1;
+ else
+ idno = to_platform_device(dev)->id;
mutex_lock(&clocks_mutex);
+
+ list_for_each_entry(p, &clocks, node) {
+ if (p->id == idno &&
+ strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
+ clk = p;
+ goto found;
+ }
+ }
+
list_for_each_entry(p, &clocks, node) {
if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
clk = p;
break;
}
}
+
+found:
mutex_unlock(&clocks_mutex);
return clk;
@@ -59,6 +81,9 @@ int clk_enable(struct clk *clk)
unsigned long flags;
int ret = 0;
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_enable)
ret = arch_clock->clk_enable(clk);
@@ -72,6 +97,9 @@ void clk_disable(struct clk *clk)
{
unsigned long flags;
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_disable)
arch_clock->clk_disable(clk);
@@ -84,6 +112,9 @@ int clk_get_usecount(struct clk *clk)
unsigned long flags;
int ret = 0;
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
spin_lock_irqsave(&clockfw_lock, flags);
ret = clk->usecount;
spin_unlock_irqrestore(&clockfw_lock, flags);
@@ -97,6 +128,9 @@ unsigned long clk_get_rate(struct clk *clk)
unsigned long flags;
unsigned long ret = 0;
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
spin_lock_irqsave(&clockfw_lock, flags);
ret = clk->rate;
spin_unlock_irqrestore(&clockfw_lock, flags);
@@ -121,6 +155,9 @@ long clk_round_rate(struct clk *clk, unsigned long rate)
unsigned long flags;
long ret = 0;
+ if (clk == NULL || IS_ERR(clk))
+ return ret;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_round_rate)
ret = arch_clock->clk_round_rate(clk, rate);
@@ -133,7 +170,10 @@ EXPORT_SYMBOL(clk_round_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags;
- int ret = 0;
+ int ret = -EINVAL;
+
+ if (clk == NULL || IS_ERR(clk))
+ return ret;
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_set_rate)
@@ -147,7 +187,10 @@ EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
unsigned long flags;
- int ret = 0;
+ int ret = -EINVAL;
+
+ if (clk == NULL || IS_ERR(clk) || parent == NULL || IS_ERR(parent))
+ return ret;
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_set_parent)
@@ -163,6 +206,9 @@ struct clk *clk_get_parent(struct clk *clk)
unsigned long flags;
struct clk * ret = NULL;
+ if (clk == NULL || IS_ERR(clk))
+ return ret;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_get_parent)
ret = arch_clock->clk_get_parent(clk);
@@ -199,6 +245,9 @@ __setup("mpurate=", omap_clk_setup);
/* Used for clocks that always have same value as the parent clock */
void followparent_recalc(struct clk *clk)
{
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
clk->rate = clk->parent->rate;
}
@@ -207,6 +256,9 @@ void propagate_rate(struct clk * tclk)
{
struct clk *clkp;
+ if (tclk == NULL || IS_ERR(tclk))
+ return;
+
list_for_each_entry(clkp, &clocks, node) {
if (likely(clkp->parent != tclk))
continue;
@@ -217,6 +269,9 @@ void propagate_rate(struct clk * tclk)
int clk_register(struct clk *clk)
{
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
mutex_lock(&clocks_mutex);
list_add(&clk->node, &clocks);
if (clk->init)
@@ -229,6 +284,9 @@ EXPORT_SYMBOL(clk_register);
void clk_unregister(struct clk *clk)
{
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
mutex_lock(&clocks_mutex);
list_del(&clk->node);
mutex_unlock(&clocks_mutex);
@@ -239,6 +297,9 @@ void clk_deny_idle(struct clk *clk)
{
unsigned long flags;
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_deny_idle)
arch_clock->clk_deny_idle(clk);
@@ -250,6 +311,9 @@ void clk_allow_idle(struct clk *clk)
{
unsigned long flags;
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
spin_lock_irqsave(&clockfw_lock, flags);
if (arch_clock->clk_allow_idle)
arch_clock->clk_allow_idle(clk);