[PATCH] Driver Core: Runtime PM callbacks for the Platform Bus V2

[Magnus Damm <magnus.damm@gmail.com>]

From: Magnus Damm <damm@igel.co.jp>

This patch adds default Runtime PM callbacks to the dev_pm_ops
belonging to the platform bus. The callbacks are weak symbols
that architecture specific code may override. Also, call
pm_runtime_enable() for the platform bus struct device.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
---

 Needed by the SuperH platform bus Runtime PM implementation.

 Changes since V1:
 - Return -ENOSYS instead of -EINVAL.

 drivers/base/platform.c |   31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

--- 0001/drivers/base/platform.c
+++ work/drivers/base/platform.c	2009-07-31 18:55:34.000000000 +0900
@@ -17,6 +17,7 @@
 #include <linux/bootmem.h>
 #include <linux/err.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
 
 #include "base.h"
 
@@ -925,6 +926,30 @@ static int platform_pm_restore_noirq(str
 
 #endif /* !CONFIG_HIBERNATION */
 
+#ifdef CONFIG_PM_RUNTIME
+
+int __weak platform_pm_runtime_suspend(struct device *dev)
+{
+	return -ENOSYS;
+};
+
+int __weak platform_pm_runtime_resume(struct device *dev)
+{
+	return -ENOSYS;
+};
+
+void __weak platform_pm_runtime_idle(struct device *dev)
+{
+};
+
+#else /* !CONFIG_PM_RUNTIME */
+
+#define platform_pm_runtime_suspend NULL
+#define platform_pm_runtime_resume NULL
+#define platform_pm_runtime_idle NULL
+
+#endif /* !CONFIG_PM_RUNTIME */
+
 static struct dev_pm_ops platform_dev_pm_ops = {
 	.prepare = platform_pm_prepare,
 	.complete = platform_pm_complete,
@@ -940,6 +965,9 @@ static struct dev_pm_ops platform_dev_pm
 	.thaw_noirq = platform_pm_thaw_noirq,
 	.poweroff_noirq = platform_pm_poweroff_noirq,
 	.restore_noirq = platform_pm_restore_noirq,
+	.runtime_suspend = platform_pm_runtime_suspend,
+	.runtime_resume = platform_pm_runtime_resume,
+	.runtime_idle = platform_pm_runtime_idle,
 };
 
 #define PLATFORM_PM_OPS_PTR	(&platform_dev_pm_ops)
@@ -968,6 +996,9 @@ int __init platform_bus_init(void)
 	error = device_register(&platform_bus);
 	if (error)
 		return error;
+
+	pm_runtime_enable(&platform_bus);
+
 	error =  bus_register(&platform_bus_type);
 	if (error)
 		device_unregister(&platform_bus);