Having a brick wall or timber/metal stud wall does not decide the type of frame, fitting very heavy fire doors to partition walls is very common and standard practise in offices, even steel doors though heavier gauge stud work is required. My last three houses have all had original door frames with a door stop pinned on and fitted to brickwork, a 1950's a 1920's and my present Victorian era house. Even now this type of frame is the norm as it allows different thicknesses of doors to be fitted to the same frame. I did some work on an architects office a few years ago where the frames came in prehung with the doors and even those had a separate door stop. By the way I worked as a dry liner for 35 years so have seen a lot doors and very few one piece frames and they were usually hardwood in commercial/ office buildings.