SMBus Driver for PIIX4 on FreeBSD

What is SMbus?

SMbus is acronim for "System Management Bus".This bus is physically like Philips's I2C bus.This bus is connected to
  1. Hardware Monitoring chip.( CPU/Case TEMP, FAN speed, Voltage mater).
  2. EEPROM in DIMM (a.k.a SPD, Serial Presence Ditection)
  3. Wakeup on LAN connector.
  4. Laptop Smart Battery System.
  5. and so on....
For FreeBSD, framework is exist.
ACPI specification contains SMBus as a way to access it.


The driver is already commited in CVS repository
,and if there is update ,I'll put here.. Some of example SMBus Application is here. This Contains LM75/78 monitor and Serial Presence Detection reader. See also My ACPI page.