Index: madwifi-ng-r2568-20070710/ath/if_ath.c
===================================================================
--- madwifi-ng-r2568-20070710.orig/ath/if_ath.c	2007-07-13 11:18:20.621471697 +0200
+++ madwifi-ng-r2568-20070710/ath/if_ath.c	2007-07-13 11:18:21.021494493 +0200
@@ -153,6 +153,7 @@
 static void ath_turbo_switch_mode(unsigned long);
 static int ath_check_beacon_done(struct ath_softc *);
 #endif
+static void ath_do_calibrate(struct net_device *);
 static void ath_beacon_send(struct ath_softc *, int *);
 static void ath_beacon_start_adhoc(struct ath_softc *, struct ieee80211vap *);
 static void ath_beacon_return(struct ath_softc *, struct ath_buf *);
@@ -4173,7 +4174,7 @@
 		DPRINTF(sc, ATH_DEBUG_BEACON_PROC,
 			"%s: missed %u consecutive beacons\n",
 			__func__, sc->sc_bmisscount);
-		if (sc->sc_bmisscount > BSTUCK_THRESH)
+		if (sc->sc_bmisscount > BSTUCK_CALIBR_THR)
 			ATH_SCHEDULE_TQUEUE(&sc->sc_bstucktq, needmark);
 		return;
 	}
@@ -4312,8 +4313,17 @@
 	 *     check will be true, in which case return 
 	 *     without resetting the driver.
 	 */
-	if (sc->sc_bmisscount <= BSTUCK_THRESH)
+	if (sc->sc_bmisscount <= BSTUCK_CALIBR_THR)
 		return;
+
+	if (sc->sc_bmisscount <= BSTUCK_RESET_THR) {
+		ATH_LOCK(sc);
+		ath_do_calibrate(dev);
+		mod_timer(&sc->sc_cal_ch, jiffies + (ath_calinterval * HZ));
+		ATH_UNLOCK(sc);
+		return;
+	}
+
 	printk("%s: stuck beacon; resetting (bmiss count %u)\n",
 		DEV_NAME(dev), sc->sc_bmisscount);
 	ath_reset(dev);
@@ -8027,17 +8037,13 @@
  * Periodically recalibrate the PHY to account
  * for temperature/environment changes.
  */
-static void
-ath_calibrate(unsigned long arg)
+static void ath_do_calibrate(struct net_device *dev)
 {
-	struct net_device *dev = (struct net_device *) arg;
 	struct ath_softc *sc = dev->priv;
 	struct ath_hal *ah = sc->sc_ah;
-	/* u_int32_t nchans; */
 	HAL_BOOL isIQdone = AH_FALSE;
 
 	sc->sc_stats.ast_per_cal++;
-
 	DPRINTF(sc, ATH_DEBUG_CALIBRATE, "%s: channel %u/%x\n",
 		__func__, sc->sc_curchan.channel, sc->sc_curchan.channelFlags);
 
@@ -8055,15 +8061,26 @@
 			__func__, sc->sc_curchan.channel);
 		sc->sc_stats.ast_per_calfail++;
 	}
-
-	ath_hal_process_noisefloor(ah);
 	if (isIQdone == AH_TRUE)
 		ath_calinterval = ATH_LONG_CALINTERVAL;
 	else
 		ath_calinterval = ATH_SHORT_CALINTERVAL;
+}
+
+static void
+ath_calibrate(unsigned long arg)
+{
+	struct net_device *dev = (struct net_device *) arg;
+	struct ath_softc *sc = dev->priv;
+	struct ath_hal *ah = sc->sc_ah;
+
+	ATH_LOCK(sc);
+	ath_do_calibrate(dev);
+	ath_hal_process_noisefloor(ah);
 
 	sc->sc_cal_ch.expires = jiffies + (ath_calinterval * HZ);
 	add_timer(&sc->sc_cal_ch);
+	ATH_UNLOCK(sc);
 }
 
 static void
Index: madwifi-ng-r2568-20070710/ath/if_athvar.h
===================================================================
--- madwifi-ng-r2568-20070710.orig/ath/if_athvar.h	2007-07-13 11:18:20.353456423 +0200
+++ madwifi-ng-r2568-20070710/ath/if_athvar.h	2007-07-13 11:18:21.021494493 +0200
@@ -538,7 +538,8 @@
  */
 #define ATH_TXQ_MOVE_Q(_tqs,_tqd)  ATH_TXQ_MOVE_MCASTQ(_tqs,_tqd)
 
-#define	BSTUCK_THRESH	10	/* # of stuck beacons before resetting NB: this is a guess*/
+#define	BSTUCK_CALIBR_THR	3	/* # of stuck beacons before restarting calibration */
+#define	BSTUCK_RESET_THR	10	/* # of stuck beacons before resetting NB: this is a guess*/
 
 struct ath_softc {
 	struct ieee80211com sc_ic;		/* NB: must be first */