This package contains all the basic i2c code, as well as a few bus drivers
(both the algorithm and the adapter drivers). There are no real chip
drivers, so on its own it is not very useful. Lots of chip drivers, as
well as more bus drivers and some additional basic code
(for SMBus emulation over i2c) and some i2c debugging tools
are found in the lm_sensors package at http://www.lm-sensors.nu.
Another place at which I2C is used is the video4linux project.