PM: Reorganize device PM initialization

Make the device power management initialization more straightforward
by moving the initialization of common (i.e. used by both runtime PM
and system suspend) fields to a separate routine.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

drivers/base/power/main.c

@@ -57,20 +57,17 @@ static pm_message_t pm_transition;
 static int async_error;
 
 /**
- * device_pm_init - Initialize the PM-related part of a device object.
+ * device_pm_sleep_init - Initialize system suspend-related device fields.
  * @dev: Device object being initialized.
  */
-void device_pm_init(struct device *dev)
+void device_pm_sleep_init(struct device *dev)
 {
 	dev->power.is_prepared = false;
 	dev->power.is_suspended = false;
 	init_completion(&dev->power.completion);
 	complete_all(&dev->power.completion);
 	dev->power.wakeup = NULL;
-	spin_lock_init(&dev->power.lock);
-	pm_runtime_init(dev);
 	INIT_LIST_HEAD(&dev->power.entry);
-	dev->power.power_state = PMSG_INVALID;
 }
 
 /**

drivers/base/power/power.h

 #include <linux/pm_qos.h>
 
+static inline void device_pm_init_common(struct device *dev)
+{
+	spin_lock_init(&dev->power.lock);
+	dev->power.power_state = PMSG_INVALID;
+}
+
 #ifdef CONFIG_PM_RUNTIME
 
 extern void pm_runtime_init(struct device *dev);
@@ -25,7 +31,7 @@ static inline struct device *to_device(struct list_head *entry)
 	return container_of(entry, struct device, power.entry);
 }
 
-extern void device_pm_init(struct device *dev);
+extern void device_pm_sleep_init(struct device *dev);
 extern void device_pm_add(struct device *);
 extern void device_pm_remove(struct device *);
 extern void device_pm_move_before(struct device *, struct device *);
@@ -34,12 +40,7 @@ extern void device_pm_move_last(struct device *);
 
 #else /* !CONFIG_PM_SLEEP */
 
-static inline void device_pm_init(struct device *dev)
-{
-	spin_lock_init(&dev->power.lock);
-	dev->power.power_state = PMSG_INVALID;
-	pm_runtime_init(dev);
-}
+static inline void device_pm_sleep_init(struct device *dev) {}
 
 static inline void device_pm_add(struct device *dev)
 {
@@ -60,6 +61,13 @@ static inline void device_pm_move_last(struct device *dev) {}
 
 #endif /* !CONFIG_PM_SLEEP */
 
+static inline void device_pm_init(struct device *dev)
+{
+	device_pm_init_common(dev);
+	device_pm_sleep_init(dev);
+	pm_runtime_init(dev);
+}
+
 #ifdef CONFIG_PM
 
 /*