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+
+The Basic Device Structure
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+struct device {
+        struct list_head g_list;
+        struct list_head node;
+        struct list_head bus_list;
+        struct list_head driver_list;
+        struct list_head intf_list;
+        struct list_head children;
+        struct device   * parent;
+
+        char    name[DEVICE_NAME_SIZE];
+        char    bus_id[BUS_ID_SIZE];
+
+        spinlock_t      lock;
+        atomic_t        refcount;
+
+        struct bus_type * bus;
+        struct driver_dir_entry dir;
+
+	u32		class_num;
+
+        struct device_driver *driver;
+        void            *driver_data;
+        void            *platform_data;
+
+        u32             current_state;
+        unsigned char *saved_state;
+
+        void    (*release)(struct device * dev);
+};
+
+Fields 
+~~~~~~
+g_list:	Node in the global device list.
+
+node:	Node in device's parent's children list.
+
+bus_list: Node in device's bus's devices list.
+
+driver_list:   Node in device's driver's devices list.
+
+intf_list:     List of intf_data. There is one structure allocated for
+	       each interface that the device supports.
+
+children:      List of child devices.
+
+parent:        *** FIXME ***
+
+name:	       ASCII description of device. 
+	       Example: " 3Com Corporation 3c905 100BaseTX [Boomerang]"
+
+bus_id:	       ASCII representation of device's bus position. This 
+	       field should be a name unique across all devices on the
+	       bus type the device belongs to. 
+
+	       Example: PCI bus_ids are in the form of
+	       <bus number>:<slot number>.<function number> 
+	       This name is unique across all PCI devices in the system.
+
+lock:	       Spinlock for the device. 
+
+refcount:      Reference count on the device.
+
+bus:	       Pointer to struct bus_type that device belongs to.
+
+dir:	       Device's sysfs directory.
+
+class_num:     Class-enumerated value of the device.
+
+driver:	       Pointer to struct device_driver that controls the device.
+
+driver_data:   Driver-specific data.
+
+platform_data: Platform data specific to the device.
+
+current_state: Current power state of the device.
+
+saved_state:   Pointer to saved state of the device. This is usable by
+	       the device driver controlling the device.
+
+release:       Callback to free the device after all references have 
+	       gone away. This should be set by the allocator of the 
+	       device (i.e. the bus driver that discovered the device).
+
+
+Programming Interface
+~~~~~~~~~~~~~~~~~~~~~
+The bus driver that discovers the device uses this to register the
+device with the core:
+
+int device_register(struct device * dev);
+
+The bus should initialize the following fields:
+
+    - parent
+    - name
+    - bus_id
+    - bus
+
+A device is removed from the core when its reference count goes to
+0. The reference count can be adjusted using:
+
+struct device * get_device(struct device * dev);
+void put_device(struct device * dev);
+
+get_device() will return a pointer to the struct device passed to it
+if the reference is not already 0 (if it's in the process of being
+removed already).
+
+A driver can access the lock in the device structure using: 
+
+void lock_device(struct device * dev);
+void unlock_device(struct device * dev);
+
+
+Attributes
+~~~~~~~~~~
+struct device_attribute {
+        struct attribute        attr;
+        ssize_t (*show)(struct device * dev, char * buf, size_t count, loff_t off);
+        ssize_t (*store)(struct device * dev, const char * buf, size_t count, loff_t off);
+};
+
+Attributes of devices can be exported via drivers using a simple
+procfs-like interface. 
+
+Please see Documentation/filesystems/sysfs.txt for more information
+on how sysfs works.
+
+Attributes are declared using a macro called DEVICE_ATTR:
+
+#define DEVICE_ATTR(name,mode,show,store)
+
+Example:
+
+DEVICE_ATTR(power,0644,show_power,store_power);
+
+This declares a structure of type struct device_attribute named
+'dev_attr_power'. This can then be added and removed to the device's
+directory using:
+
+int device_create_file(struct device *device, struct device_attribute * entry);
+void device_remove_file(struct device * dev, struct device_attribute * attr);
+
+Example:
+
+device_create_file(dev,&dev_attr_power);
+device_remove_file(dev,&dev_attr_power);
+
+The file name will be 'power' with a mode of 0644 (-rw-r--r--).
+