Thank you, I've submitted a case to our internal tracking system.
That API shows 3 return values: CYRET_SUCCESS, CYRET_BAD_PARAM, CYRET_UNKNOWN. I've reviewed through the code and those are the only 3 values that can be returned by this function. I don't understand your statement about power save modes.
Now I see that the issue was in the description of the return values and not the value of the return values. This has been fixed in the datasheet that ships with 3.0.