net80211: correct return code for ieee80211_ampdu_request()

[bz]

Summary

We used to return the result of (*ic_send_action) directly but
ieee80211_ampdu_request() returns 1 on success and 0 on error,
which is contrary to the result of (*ic_send_action). Deal with
that accordingly and update the documentation of the function.

Sponsored by: The FreeBSD Foundation
MFC after: 3 days

[emaste]

sys/net80211/ieee80211_ht.c

2839

I suppose ieee80211_ampdu_request ought to return bool.
Either way, to me return (error == 0) is clear.

[bz]

sys/net80211/ieee80211_ht.c

2839

Well, I would happily be able to propagate an error in the future (or act upon as we adjusted state early on).

I guess for the moment we can return error == 0 indeed. Saves vertical space :)

[bz]

Update treturn as suggested by @emaste.

[adrian]

Oh, there's no callers of ieee80211_ampdu_request() outside of net80211? I was worried that the existing AMPDU implementing drivers would hiccup with the return value changing!

[bz]

In D54794#1252564, @adrian wrote:

Oh, there's no callers of ieee80211_ampdu_request() outside of net80211? I was worried that the existing AMPDU implementing drivers would hiccup with the return value changing!

No, the caller in net80211 is (void). But I wanted to use it from LinuxKPI and I need to know the result as otherwise firmware and us will not be friends.