diff --git a/drivers/net/wireless/ath5k/ath5k.h b/drivers/net/wireless/ath5k/ath5k.h
index 878609f1bf39..c79066b38d3b 100644
--- a/drivers/net/wireless/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath5k/ath5k.h
@@ -486,8 +486,8 @@ struct ath5k_beacon_state {
  * TSF to TU conversion:
  *
  * TSF is a 64bit value in usec (microseconds).
- * TU is a 32bit value in roughly msec (milliseconds): usec / 1024
- * (1000ms equals 976 TU)
+ * TU is a 32bit value and defined by IEEE802.11 (page 6) as "A measurement of
+ * time equal to 1024 usec", so it's roughly milliseconds (usec / 1024).
  */
 #define TSF_TO_TU(_tsf) (u32)((_tsf) >> 10)
 
diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index 5ff115da91e3..de590163a07e 100644
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -2554,7 +2554,7 @@ ath5k_config(struct ieee80211_hw *hw,
 {
 	struct ath5k_softc *sc = hw->priv;
 
-	sc->bintval = conf->beacon_int * 1000 / 1024;
+	sc->bintval = conf->beacon_int;
 	ath5k_setcurmode(sc, conf->phymode);
 
 	return ath5k_chan_set(sc, conf->chan);
@@ -2570,7 +2570,7 @@ ath5k_config_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 
 	/* Set to a reasonable value. Note that this will
 	 * be set to mac80211's value at ath5k_config(). */
-	sc->bintval = 1000 * 1000 / 1024;
+	sc->bintval = 1000;
 	mutex_lock(&sc->lock);
 	if (sc->vif != vif) {
 		ret = -EIO;
diff --git a/drivers/net/wireless/ath5k/base.h b/drivers/net/wireless/ath5k/base.h
index 7ba2223d2247..20c946926090 100644
--- a/drivers/net/wireless/ath5k/base.h
+++ b/drivers/net/wireless/ath5k/base.h
@@ -164,7 +164,7 @@ struct ath5k_softc {
 	struct ath5k_buf	*bbuf;		/* beacon buffer */
 	unsigned int		bhalq,		/* SW q for outgoing beacons */
 				bmisscount,	/* missed beacon transmits */
-				bintval,	/* beacon interval */
+				bintval,	/* beacon interval in TU */
 				bsent;
 
 	struct timer_list	calib_tim;	/* calibration timer */