quoted

+     struct sta_ampdu_mlme ampdu_mlme;
+     int timer_to_tid[STA_TID_NUM];  /* convert timer id to tid */

Since you only use that as an identity mapping it can well be a u8
array. Not that I like the trick used, but I don't see any good way to
avoid it either.

yes... that was quite an irritating issue, had to use this kind of
mechanism here.
i will check changing type to u8 (need to exmine if it will cause any
addresses problems)