1 files changed, 54 insertions, 3 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index a62799f2ab0..182192892d4 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -106,7 +106,7 @@ extern int bus_unregister_notifier(struct bus_type *bus,
 
 /* All 4 notifers below get called with the target struct device *
  * as an argument. Note that those functions are likely to be called
- * with the device semaphore held in the core, so be careful.
+ * with the device lock held in the core, so be careful.
  */
 #define BUS_NOTIFY_ADD_DEVICE		0x00000001 /* device added */
 #define BUS_NOTIFY_DEL_DEVICE		0x00000002 /* device removed */
@@ -251,8 +251,10 @@ extern struct device *class_find_device(struct class *class,
 
 struct class_attribute {
 	struct attribute attr;
-	ssize_t (*show)(struct class *class, char *buf);
-	ssize_t (*store)(struct class *class, const char *buf, size_t count);
+	ssize_t (*show)(struct class *class, struct class_attribute *attr,
+			char *buf);
+	ssize_t (*store)(struct class *class, struct class_attribute *attr,
+			const char *buf, size_t count);
 };
 
 #define CLASS_ATTR(_name, _mode, _show, _store)			\
@@ -263,6 +265,23 @@ extern int __must_check class_create_file(struct class *class,
 extern void class_remove_file(struct class *class,
 			      const struct class_attribute *attr);
 
+/* Simple class attribute that is just a static string */
+
+struct class_attribute_string {
+	struct class_attribute attr;
+	char *str;
+};
+
+/* Currently read-only only */
+#define _CLASS_ATTR_STRING(_name, _mode, _str) \
+	{ __ATTR(_name, _mode, show_class_attr_string, NULL), _str }
+#define CLASS_ATTR_STRING(_name, _mode, _str) \
+	struct class_attribute_string class_attr_##_name = \
+		_CLASS_ATTR_STRING(_name, _mode, _str)
+
+extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr,
+                        char *buf);
+
 struct class_interface {
 	struct list_head	node;
 	struct class		*class;
@@ -472,6 +491,38 @@ static inline int device_is_registered(struct device *dev)
 	return dev->kobj.state_in_sysfs;
 }
 
+static inline void device_enable_async_suspend(struct device *dev)
+{
+	if (dev->power.status == DPM_ON)
+		dev->power.async_suspend = true;
+}
+
+static inline void device_disable_async_suspend(struct device *dev)
+{
+	if (dev->power.status == DPM_ON)
+		dev->power.async_suspend = false;
+}
+
+static inline bool device_async_suspend_enabled(struct device *dev)
+{
+	return !!dev->power.async_suspend;
+}
+
+static inline void device_lock(struct device *dev)
+{
+	down(&dev->sem);
+}
+
+static inline int device_trylock(struct device *dev)
+{
+	return down_trylock(&dev->sem);
+}
+
+static inline void device_unlock(struct device *dev)
+{
+	up(&dev->sem);
+}
+
 void driver_init(void);
 
 /*