I2c-dev.c is part of I2C equipment, access interface device, the access to the hardware is realized by i2c_adapter. It is during initialization, need to register a i2c_driver to the I2C Core. I think this is just to let the user access layer of I2C bus, I2C bus if the kernel state visit, then there is no need to worry about it but we need to refer to it to realize our own i2c_driver, and the i2c_driver is registered to the I2C Core.

-I2c-dev.c is part of I2C equipment, access interface device, the access to the hardware is realized by i2c_adapter. It is during initialization, need to register a i2c_driver to the I2C Core. I think this is just to let the user access layer of I2C bus, I2C bus if the kernel state visit, then there is no need to worry about it　but we need to refer to it to realize our own i2c_driver, and the i2c_driver is registered to the I2C Core.