-extern int i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
- int num);
-extern u32 i2c_dw_func(struct i2c_adapter *adap);
-extern irqreturn_t i2c_dw_isr(int this_irq, void *dev_id);
-extern void i2c_dw_enable(struct dw_i2c_dev *dev);
-extern u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev);