How to restrict OB52 postings periods user level

Hi Experts,

I have a scenario in below:

Business required only one posting period variant for 2 co.codes. some times its required to open closed posting period for Co.Code 1 after closing the books for some adjustment entries.. But 2nd company code people also allowing to post becoz of I used same posting period variant for both co.codes.

Kindly advaise how can I restirict at user level or co.code level, But we need only one posting period variant for both the co.codes.

Regards

Srini