Couldn't find reference for i2c_smbus functinos

[Jenkins, Clive]

> You can do SMBus level transactions (see documentation file
smbus-protocol
> for details) through the following functions:
>   __s32 i2c_smbus_write_quick(int file, __u8 value);
> ...
> Am I missing any information about the location of the above
functions?

Try reading
http://www.lm-sensors.org/browser/i2c/trunk/doc/dev-interface
and other material on the lm-sensors site

> Do I need to implement the above functions?

No.