d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[ath] revert the previous commit, after reading the 802.11-2012 spec a bit more.

Browse Source 
The 802.11-2012 spec talks about this - section 10.1.3.2 - Beacon Generation
in Infrastructure Networks.  So yes, we should be expecting beacons to be
going out in multiples of intval.

Silly adrian.

So:

* fix the FreeBSD APs that are sending beacons at incorrect TBTTs (target
  beacon transmit time); and
* yes indeed we will have to wake up out of network sleep until we sync
  a beacon.
This commit is contained in:
Adrian Chadd 2016-11-28 17:06:35 +00:00
parent de4a194549
commit 872f3a66dd
1 changed files with 7 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
sys/dev/ath/if_ath_beacon.c
View File

@ -965,9 +965,9 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
intval = ni->ni_intval & HAL_BEACON_PERIOD;
}
/*
* Note: rounding up to the next intval can cause problems.
* Note: rounding up to the next intval can cause problems with
* bad APs when we're in powersave mode.
*
* In STA mode with powersave enabled, beacons are only received
* whenever the beacon timer fires to wake up the hardware.
@ -975,17 +975,14 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
* that the AP has started transmitting beacons at TSF values that
* are multiples of intval, versus say being 25 TU off.
*
* I'm not sure why nexttbtt is rounded up to the intval.
* If we sync against a beacon that is way out, we should
* take a beacon miss and re-sync against the next beacon.
*
* So for now - don't round up if we're in STA mode.
* Maybe later (when someone eventually does powersave+IBSS,
* powersave+MBSS) this can be flipped on for those too.
* The specification (802.11-2012 10.1.3.2 - Beacon Generation in
* Infrastructure Networks) requires APs be beaconing at a
* mutiple of intval. So, if bintval=100, then we shouldn't
* get beacons at intervals other than around multiples of 100.
*/
if (nexttbtt == 0) /* e.g. for ap mode */
nexttbtt = intval;
else if ((ic->ic_opmode != IEEE80211_M_STA) && intval) /* NB: can be 0 for monitor mode */
else
nexttbtt = roundup(nexttbtt, intval);
DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt %u intval %u (%u)\n",