+extern struct sysfs_class_device *sysfs_open_class_device
+ (const unsigned char *class, const unsigned char *name);
+extern struct sysfs_device *sysfs_get_classdev_device
+ (struct sysfs_class_device *clsdev);
+extern struct sysfs_driver *sysfs_get_classdev_driver
+ (struct sysfs_class_device *clsdev);
+extern struct sysfs_class_device *sysfs_get_classdev_parent
+ (struct sysfs_class_device *clsdev);