2011-05-16 21:22:09

by Felix Fietkau

[permalink] [raw]
Subject: [PATCH] ath9k: fix ad-hoc mode beacon selection

In ad-hoc mode, beacon timers are configured differently compared to AP
mode, and (depending on the scenario) can vary enough to make the beacon
tasklet not detect slot 0 based on the TSF.
Since staggered beacons are not (and cannot be) used in ad-hoc mode, it
makes more sense to just hardcode slot 0 here, avoiding unnecessary
TSF reads and calculations.

Signed-off-by: Felix Fietkau <[email protected]>
Reported-by: Rajkumar Manoharan <[email protected]>
---
drivers/net/wireless/ath/ath9k/beacon.c | 32 +++++++++++++++++++-----------
1 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 637dbc5..c7f4679 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -351,9 +351,7 @@ void ath_beacon_tasklet(unsigned long data)
struct ath_buf *bf = NULL;
struct ieee80211_vif *vif;
int slot;
- u32 bfaddr, bc = 0, tsftu;
- u64 tsf;
- u16 intval;
+ u32 bfaddr, bc = 0;

/*
* Check if the previous beacon has gone out. If
@@ -388,17 +386,27 @@ void ath_beacon_tasklet(unsigned long data)
* on the tsf to safeguard against missing an swba.
*/

- intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;

- tsf = ath9k_hw_gettsf64(ah);
- tsf += TU_TO_USEC(ah->config.sw_beacon_response_time);
- tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
- slot = (tsftu % (intval * ATH_BCBUF)) / intval;
- vif = sc->beacon.bslot[slot];
+ if (ah->opmode == NL80211_IFTYPE_AP) {
+ u16 intval;
+ u32 tsftu;
+ u64 tsf;
+
+ intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
+ tsf = ath9k_hw_gettsf64(ah);
+ tsf += TU_TO_USEC(ah->config.sw_beacon_response_time);
+ tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
+ slot = (tsftu % (intval * ATH_BCBUF)) / intval;
+ vif = sc->beacon.bslot[slot];
+
+ ath_dbg(common, ATH_DBG_BEACON,
+ "slot %d [tsf %llu tsftu %u intval %u] vif %p\n",
+ slot, tsf, tsftu / ATH_BCBUF, intval, vif);
+ } else {
+ slot = 0;
+ vif = sc->beacon.bslot[slot];
+ }

- ath_dbg(common, ATH_DBG_BEACON,
- "slot %d [tsf %llu tsftu %u intval %u] vif %p\n",
- slot, tsf, tsftu / ATH_BCBUF, intval, vif);

bfaddr = 0;
if (vif) {
--
1.7.3.2