sh: clkfwk: Add resume from hibernation support.
authorFrancesco VIRLINZI <francesco.virlinzi@st.com>
Wed, 11 Mar 2009 07:42:05 +0000 (07:42 +0000)
committerPaul Mundt <lethal@linux-sh.org>
Wed, 11 Mar 2009 08:18:50 +0000 (17:18 +0900)
This patch adds PM support to the clock framework.
With this, resume from hibernation is properly supported.

Signed-off-by: Francesco Virlinzi <francesco.virlinzi@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
arch/sh/kernel/cpu/clock.c

index 332a179..3209a87 100644 (file)
@@ -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>
@@ -358,6 +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;