Merge branch 'master' of /home/sam/kernel/linux-2.6/
[pandora-kernel.git] / arch / arm / plat-omap / clock.c
index 84fd656..7f45c7c 100644 (file)
@@ -11,7 +11,6 @@
  * published by the Free Software Foundation.
  */
 #include <linux/version.h>
-#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/err.h>
 #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>
 
 #include <asm/arch/clock.h>
 
-LIST_HEAD(clocks);
-static DECLARE_MUTEX(clocks_sem);
-DEFINE_SPINLOCK(clockfw_lock);
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+static DEFINE_SPINLOCK(clockfw_lock);
 
 static struct clk_functions *arch_clock;
 
 /*-------------------------------------------------------------------------
- * Standard clock functions defined in asm/hardware/clock.h
+ * 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;
+               }
+       }
 
-       down(&clocks_sem);
        list_for_each_entry(p, &clocks, node) {
                if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
                        clk = p;
                        break;
                }
        }
-       up(&clocks_sem);
+
+found:
+       mutex_unlock(&clocks_mutex);
 
        return clk;
 }
@@ -58,13 +80,12 @@ 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 (clk->enable)
-               ret = clk->enable(clk);
-       else if (arch_clock->clk_enable)
+       if (arch_clock->clk_enable)
                ret = arch_clock->clk_enable(clk);
-       else
-               printk(KERN_ERR "Could not enable clock %s\n", clk->name);
        spin_unlock_irqrestore(&clockfw_lock, flags);
 
        return ret;
@@ -75,47 +96,24 @@ void clk_disable(struct clk *clk)
 {
        unsigned long flags;
 
+       if (clk == NULL || IS_ERR(clk))
+               return;
+
        spin_lock_irqsave(&clockfw_lock, flags);
-       if (clk->disable)
-               clk->disable(clk);
-       else if (arch_clock->clk_disable)
+       if (arch_clock->clk_disable)
                arch_clock->clk_disable(clk);
-       else
-               printk(KERN_ERR "Could not disable clock %s\n", clk->name);
        spin_unlock_irqrestore(&clockfw_lock, flags);
 }
 EXPORT_SYMBOL(clk_disable);
 
-int clk_use(struct clk *clk)
-{
-       unsigned long flags;
-       int ret = 0;
-
-       spin_lock_irqsave(&clockfw_lock, flags);
-       if (arch_clock->clk_use)
-               ret = arch_clock->clk_use(clk);
-       spin_unlock_irqrestore(&clockfw_lock, flags);
-
-       return ret;
-}
-EXPORT_SYMBOL(clk_use);
-
-void clk_unuse(struct clk *clk)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&clockfw_lock, flags);
-       if (arch_clock->clk_unuse)
-               arch_clock->clk_unuse(clk);
-       spin_unlock_irqrestore(&clockfw_lock, flags);
-}
-EXPORT_SYMBOL(clk_unuse);
-
 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);
@@ -129,6 +127,9 @@ 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);
@@ -145,7 +146,7 @@ void clk_put(struct clk *clk)
 EXPORT_SYMBOL(clk_put);
 
 /*-------------------------------------------------------------------------
- * Optional clock functions defined in asm/hardware/clock.h
+ * Optional clock functions defined in include/linux/clk.h
  *-------------------------------------------------------------------------*/
 
 long clk_round_rate(struct clk *clk, unsigned long rate)
@@ -153,6 +154,9 @@ 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);
@@ -165,7 +169,10 @@ 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)
@@ -179,7 +186,10 @@ 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)
@@ -195,6 +205,9 @@ 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);
@@ -231,6 +244,9 @@ __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;
 }
 
@@ -239,6 +255,9 @@ 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;
@@ -249,11 +268,14 @@ void propagate_rate(struct clk * tclk)
 
 int clk_register(struct clk *clk)
 {
-       down(&clocks_sem);
+       if (clk == NULL || IS_ERR(clk))
+               return -EINVAL;
+
+       mutex_lock(&clocks_mutex);
        list_add(&clk->node, &clocks);
        if (clk->init)
                clk->init(clk);
-       up(&clocks_sem);
+       mutex_unlock(&clocks_mutex);
 
        return 0;
 }
@@ -261,9 +283,12 @@ EXPORT_SYMBOL(clk_register);
 
 void clk_unregister(struct clk *clk)
 {
-       down(&clocks_sem);
+       if (clk == NULL || IS_ERR(clk))
+               return;
+
+       mutex_lock(&clocks_mutex);
        list_del(&clk->node);
-       up(&clocks_sem);
+       mutex_unlock(&clocks_mutex);
 }
 EXPORT_SYMBOL(clk_unregister);
 
@@ -271,6 +296,9 @@ 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);
@@ -282,6 +310,9 @@ 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);