Stefan Johansen is feeling settled at Celtic and has no intention of pushing for a move any time soon.
AC Milan CEO Adriano Galliani says the club will explore the possibility of taking Liverpool midfielder Suso in January.
Cywka's current deal expires this summer and the Tykes were keen to tie down the Pole to a new contract.
However, both parties have failed to agree terms and the 25-year-old seems set to leave on a free transfer.
The news is sure to alert a host of clubs to the availability of the former Wigan and Derby man.
Cywka made 52 appearances and scored eight goals during his two-year spell at Barnsley.