2) Could be icn8318 by Hans de Goede be adopted for icn85xx?

chipone_icn8318.c lacks ACPI support. It may not be difficult to add though.

The question is if both chips are sufficiently compatible.

how it is possible to use atmel_mxt_ts module for chipone? or what is the trick?

That sounds very odd. Perhaps they share the same control interface?
Or perhaps Chipone just cloned the Atmel chips...

I'm pretty certain that a specific firmware is required for your chip, though.