i2c-0 smbus SMBus PIIX4 adapter port 0 at ff00 SMBus adapter i2c-1 smbus SMBus PIIX4 adapter port 2 at ff00 SMBus adapter i2c-2 smbus SMBus PIIX4 adapter port 1 at ff20 SMBus adapter i2c-3 i2c mga i2c I2C adapter