Generic services in HCM P and F in ECC EhP4

Hello Friends,

I am working on HCM Process and Forms in ECC 6.0 EhP4.

Custom infotype 9xxx record needs to be created. Can we add custom infotype 9xxx to standard backend service SAP_PD and use the standard service. Or do we need to create a generic service for the same.

Please advise.

John.