diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_init.c b/drivers/net/wireless/mediatek/mt76/mt76x2_init.c
index dd4c1127797efcf4b557c8bad3843cdcac776278..276c6b6bec95c380634d7a460870ccc12e1b0aa8 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76x2_init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x2_init.c
@@ -482,7 +482,10 @@ void mt76x2_set_tx_ackto(struct mt76x2_dev *dev)
 {
 	u8 ackto, sifs, slottime = dev->slottime;
 
+	/* As defined by IEEE 802.11-2007 17.3.8.6 */
 	slottime += 3 * dev->coverage_class;
+	mt76_rmw_field(dev, MT_BKOFF_SLOT_CFG,
+		       MT_BKOFF_SLOT_CFG_SLOTTIME, slottime);
 
 	sifs = mt76_get_field(dev, MT_XIFS_TIME_CFG,
 			      MT_XIFS_TIME_CFG_OFDM_SIFS);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
index 81c58f865c6423c6ebcb2285dbb29f94eaa514e4..539dda8a59e2afc21a44845924e93fc8764812d0 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
@@ -247,8 +247,7 @@ mt76x2_bss_info_changed(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		int slottime = info->use_short_slot ? 9 : 20;
 
 		dev->slottime = slottime;
-		mt76_rmw_field(dev, MT_BKOFF_SLOT_CFG,
-			       MT_BKOFF_SLOT_CFG_SLOTTIME, slottime);
+		mt76x2_set_tx_ackto(dev);
 	}
 
 	mutex_unlock(&dev->mutex);