As you may have noticed, some things have changed in this package.

The directory layout is completely different. See DIRECTORIES if you want
to know more.

Kernel modules have changed their name. Here is the mapping from old to new:
  algo_bit  => i2c-algo-bit
  algo_pcf  => i2c-algo-pcf
  bit_elv   => i2c-elv
  bit_par   => i2c-philips-par
  bit_velle => i2c-velleman
  pcf_isa   => i2c-elektor

The build system has changed. The default system now is one which does not
write access to your kernel tree. At the top of the global Makefile is 
an option BUILD_SYSTEM which you can set to `i2c' to return to the old way.