[power] Add PM info structure to struct device and PM registration functions.

- struct device_pm_info 
  - Defined in include/linux/pm.h.
  - Statically allocated in struct device (->power)
  - Body is empty if CONFIG_PM=n

- deivce_pm_{add,remove}
  - Called from device_{add,del} respectively.
  - Adds device to internal list of power managed objects and creates
    attribute group for device. 
    (Group currently empty, but placeholder directory is created for now)
  - Are defined as empty statc inline's when CONFIG_PM=n.

drivers/base/base.h

@@ -13,3 +13,21 @@ struct class_device_attribute *to_class_dev_attr(struct attribute *_attr)
 {
 	return container_of(_attr,struct class_device_attribute,attr);
 }
+
+
+#ifdef CONFIG_PM
+
+extern int device_pm_add(struct device *);
+extern void device_pm_remove(struct device *);
+
+#else
+
+static inline int device_pm_add(struct device * dev)
+{
+	return 0;
+}
+static inline void device_pm_remove(struct device * dev)
+{
+
+}
+#endif

drivers/base/core.c

@@ -230,6 +230,8 @@ int device_add(struct device *dev)
 
 	bus_add_device(dev);
 
+	device_pm_add(dev);
+
 	/* notify platform of device entry */
 	if (platform_notify)
 		platform_notify(dev);
@@ -304,6 +306,8 @@ void device_del(struct device * dev)
 {
 	struct device * parent = dev->parent;
 
+	device_pm_remove(dev);
+
 	down_write(&devices_subsys.rwsem);
 	if (parent)
 		list_del_init(&dev->node);

drivers/base/power/Makefile

 obj-y			:= shutdown.o
-obj-$(CONFIG_PM)	+= suspend.o resume.o
+obj-$(CONFIG_PM)	+= main.o suspend.o resume.o

drivers/base/power/main.c

+/*
+ * drivers/base/power/main.c - Where the driver meets power management.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Open Source Development Lab
+ *
+ * This file is released under the GPLv2
+ *
+ *
+ * The driver model core calls device_pm_add() when a device is registered.
+ * This will intialize the embedded device_pm_info object in the device
+ * and add it to the list of power-controlled devices. sysfs entries for
+ * controlling device power management will also be added.
+ *
+ * A different set of lists than the global subsystem list are used to 
+ * keep track of power info because we use different lists to hold 
+ * devices based on what stage of the power management process they 
+ * are in. The power domain dependencies may also differ from the 
+ * ancestral dependencies that the subsystem list maintains.
+ */
+
+#define DEBUG
+
+#include <linux/device.h>
+
+
+static LIST_HEAD(dpm_active_list);
+
+static spinlock_t dpm_lock = SPIN_LOCK_UNLOCKED;
+static DECLARE_MUTEX(dpm_sem);
+
+static struct attribute power_attrs[] = {
+	{ .name = NULL },
+};
+static struct attribute_group pm_attr_group = {
+	.name	= "pm",
+	.attrs	= power_attrs,
+};
+
+int device_pm_add(struct device * dev)
+{
+	int error;
+
+	pr_debug("PM: Adding info for %s:%s\n",
+		 dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
+	down(&dpm_sem);
+	spin_lock(&dpm_lock);
+	list_add_tail(&dev->power.entry,&dpm_active_list);
+	spin_unlock(&dpm_lock);
+	error = sysfs_create_group(&dev->kobj,&pm_attr_group);
+	up(&dpm_sem);
+	return error;
+}
+
+void device_pm_remove(struct device * dev)
+{
+	pr_debug("PM: Removing info for %s:%s\n",
+		 dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
+	down(&dpm_sem);
+	sysfs_remove_group(&dev->kobj,&pm_attr_group);
+	spin_lock(&dpm_lock);
+	list_del(&dev->power.entry);
+	spin_unlock(&dpm_lock);
+	up(&dpm_sem);
+}

include/linux/device.h

@@ -19,6 +19,7 @@
 #include <linux/types.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
+#include <linux/pm.h>
 #include <asm/semaphore.h>
 #include <asm/atomic.h>
 
@@ -41,13 +42,6 @@ enum {
 	RESUME_ENABLE,
 };
 
-enum device_state {
-	DEVICE_UNINITIALIZED	= 0,
-	DEVICE_INITIALIZED	= 1,
-	DEVICE_REGISTERED	= 2,
-	DEVICE_GONE		= 3,
-};
-
 struct device;
 struct device_driver;
 struct class;
@@ -64,8 +58,8 @@ struct bus_type {
 	struct device * (*add)	(struct device * parent, char * bus_id);
 	int		(*hotplug) (struct device *dev, char **envp, 
 				    int num_envp, char *buffer, int buffer_size);
-};
 
+};
 
 extern int bus_register(struct bus_type * bus);
 extern void bus_unregister(struct bus_type * bus);
@@ -267,7 +261,7 @@ struct device {
 	void		*driver_data;	/* data private to the driver */
 	void		*platform_data;	/* Platform specific data (e.g. ACPI,
 					   BIOS data relevant to device) */
-
+	struct dev_pm_info	power;
 	u32		power_state;	/* Current operating state. In
 					   ACPI-speak, this is D0-D3, D0
 					   being fully functional, and D3

include/linux/pm.h

@@ -188,6 +188,15 @@ static inline void pm_dev_idle(struct pm_dev *dev) {}
 extern void (*pm_idle)(void);
 extern void (*pm_power_off)(void);
 
+
+struct dev_pm_info {
+#ifdef	CONFIG_PM
+	u32			power_state;
+	u8			* saved_state;
+	struct list_head	entry;
+#endif
+};
+
 #endif /* __KERNEL__ */
 
 #endif /* _LINUX_PM_H */