sh: clkfwk: Add resume from hibernation support.

[linux-2.6-omap-h63xx.git] / arch / sh / kernel / cpu / clock.c

diff --git a/arch/sh/kernel/cpu/clock.c b/arch/sh/kernel/cpu/clock.c
index b7e46d5bba439057a6f503d72b509515554db89a..3209a8740fa4c7aca749348ddd40a3f1efe3a4f1 100644 (file)
--- a/arch/sh/kernel/cpu/clock.c
+++ b/arch/sh/kernel/cpu/clock.c
@@ -20,6 +20,8 @@
 #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>
 #include <linux/err.h>
 #include <linux/platform_device.h>
@@ -117,6 +119,11 @@ int clk_enable(struct clk *clk)
        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);
@@ -147,9 +154,14 @@ void clk_disable(struct clk *clk)
 {
        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);
 
@@ -229,6 +241,35 @@ void clk_recalc_rate(struct clk *clk)
 }
 EXPORT_SYMBOL_GPL(clk_recalc_rate);
 
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+       int ret = -EINVAL;
+       struct clk *old;
+
+       if (!parent || !clk)
+               return ret;
+
+       old = clk->parent;
+       if (likely(clk->ops && clk->ops->set_parent)) {
+               unsigned long flags;
+               spin_lock_irqsave(&clock_lock, flags);
+               ret = clk->ops->set_parent(clk, parent);
+               spin_unlock_irqrestore(&clock_lock, flags);
+               clk->parent = (ret ? old : parent);
+       }
+
+       if (unlikely(clk->flags & CLK_RATE_PROPAGATES))
+               propagate_rate(clk);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_parent);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+       return clk->parent;
+}
+EXPORT_SYMBOL_GPL(clk_get_parent);
+
 long clk_round_rate(struct clk *clk, unsigned long rate)
 {
        if (likely(clk->ops && clk->ops->round_rate)) {
@@ -319,6 +360,68 @@ static int show_clocks(char *buf, char **start, off_t off,
        return p - buf;
 }
 
+#ifdef CONFIG_PM
+static int clks_sysdev_suspend(struct sys_device *dev, pm_message_t state)
+{
+       static pm_message_t prev_state;
+       struct clk *clkp;
+
+       switch (state.event) {
+       case PM_EVENT_ON:
+               /* Resumeing from hibernation */
+               if (prev_state.event == PM_EVENT_FREEZE) {
+                       list_for_each_entry(clkp, &clock_list, node)
+                               if (likely(clkp->ops)) {
+                                       if (likely(clkp->ops->set_parent))
+                                               clkp->ops->set_parent(clkp,
+                                                       clkp->parent);
+                                       if (likely(clkp->ops->set_rate))
+                                               clkp->ops->set_rate(clkp,
+                                                       clkp->rate, NO_CHANGE);
+                                       else if (likely(clkp->ops->recalc))
+                                               clkp->ops->recalc(clkp);
+                                       }
+               }
+               break;
+       case PM_EVENT_FREEZE:
+               break;
+       case PM_EVENT_SUSPEND:
+               break;
+       }
+
+       prev_state = state;
+       return 0;
+}
+
+static int clks_sysdev_resume(struct sys_device *dev)
+{
+       return clks_sysdev_suspend(dev, PMSG_ON);
+}
+
+static struct sysdev_class clks_sysdev_class = {
+       .name = "clks",
+};
+
+static struct sysdev_driver clks_sysdev_driver = {
+       .suspend = clks_sysdev_suspend,
+       .resume = clks_sysdev_resume,
+};
+
+static struct sys_device clks_sysdev_dev = {
+       .cls = &clks_sysdev_class,
+};
+
+static int __init clk_sysdev_init(void)
+{
+       sysdev_class_register(&clks_sysdev_class);
+       sysdev_driver_register(&clks_sysdev_class, &clks_sysdev_driver);
+       sysdev_register(&clks_sysdev_dev);
+
+       return 0;
+}
+subsys_initcall(clk_sysdev_init);
+#endif
+
 int __init clk_init(void)
 {
        int i, ret = 0;