+int v4l2_prio_init(struct v4l2_prio_state *global);
+int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
+ enum v4l2_priority new);
+int v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
+int v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority *local);
+enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
+int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority *local);
+
+/* ------------------------------------------------------------------------- */
+
+/* Control helper functions */
+
+int v4l2_ctrl_check(struct v4l2_ext_control *ctrl, struct v4l2_queryctrl *qctrl,
+ const char **menu_items);
+const char *v4l2_ctrl_get_name(u32 id);
+const char **v4l2_ctrl_get_menu(u32 id);
+int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 min, s32 max, s32 step, s32 def);
+int v4l2_ctrl_query_fill_std(struct v4l2_queryctrl *qctrl);
+int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu,
+ struct v4l2_queryctrl *qctrl, const char **menu_items);
+#define V4L2_CTRL_MENU_IDS_END (0xffffffff)
+int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids);
+u32 v4l2_ctrl_next(const u32 * const *ctrl_classes, u32 id);
+
+/* ------------------------------------------------------------------------- */
+
+/* Register/chip ident helper function */
+
+struct i2c_client; /* forward reference */
+int v4l2_chip_match_i2c_client(struct i2c_client *c, const struct v4l2_dbg_match *match);
+int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_dbg_chip_ident *chip,
+ u32 ident, u32 revision);
+int v4l2_chip_match_host(const struct v4l2_dbg_match *match);
+
+/* ------------------------------------------------------------------------- */
+
+/* Helper function for I2C legacy drivers */
+
+struct i2c_driver;
+struct i2c_adapter;
+struct i2c_client;
+struct i2c_device_id;
+struct v4l2_device;
+struct v4l2_subdev;
+struct v4l2_subdev_ops;
+
+int v4l2_i2c_attach(struct i2c_adapter *adapter, int address, struct i2c_driver *driver,
+ const char *name,
+ int (*probe)(struct i2c_client *, const struct i2c_device_id *));
+
+/* Load an i2c module and return an initialized v4l2_subdev struct.
+ Only call request_module if module_name != NULL.
+ The client_type argument is the name of the chip that's on the adapter. */
+struct v4l2_subdev *v4l2_i2c_new_subdev(struct i2c_adapter *adapter,
+ const char *module_name, const char *client_type, u8 addr);
+/* Probe and load an i2c module and return an initialized v4l2_subdev struct.
+ Only call request_module if module_name != NULL.
+ The client_type argument is the name of the chip that's on the adapter. */
+struct v4l2_subdev *v4l2_i2c_new_probed_subdev(struct i2c_adapter *adapter,
+ const char *module_name, const char *client_type,
+ const unsigned short *addrs);
+/* Initialize an v4l2_subdev with data from an i2c_client struct */
+void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
+ const struct v4l2_subdev_ops *ops);
+
+/* ------------------------------------------------------------------------- */
+
+/* Internal ioctls */