It's somewhat odd to me that the structure is "firmware_stat" but most
of the functions are "fw_loading_*". That seems inconsistent for a
structure that is (currently) only used by these functions.
I would personally do either:
a) "struct fw_load_status" and "fw_load_*()"
or
b) "struct firmware_load_stat" and "firmware_load_*()"
I'd also change the function names from "loading" -> "load", similar to
how userland has read(2), not reading(2).