ath9k: Fix bug in assigning sequence number

The internal, driver-specific maintenance of sequence
numbers is applicable only for HT frames.

Also, remove comments that are not relevant anymore.
Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/xmit.c

@@ -1414,17 +1414,9 @@ static void assign_aggr_tid_seqno(struct sk_buff *skb,
 	 * For HT capable stations, we save tidno for later use.
 	 * We also override seqno set by upper layer with the one
 	 * in tx aggregation state.
-	 *
-	 * If fragmentation is on, the sequence number is
-	 * not overridden, since it has been
-	 * incremented by the fragmentation routine.
-	 *
-	 * FIXME: check if the fragmentation threshold exceeds
-	 * IEEE80211 max.
 	 */
 	tid = ATH_AN_2_TID(an, bf->bf_tidno);
-	hdr->seq_ctrl = cpu_to_le16(tid->seq_next <<
-			IEEE80211_SEQ_SEQ_SHIFT);
+	hdr->seq_ctrl = cpu_to_le16(tid->seq_next << IEEE80211_SEQ_SEQ_SHIFT);
 	bf->bf_seqno = tid->seq_next;
 	INCR(tid->seq_next, IEEE80211_SEQ_MAX);
 }
@@ -1636,7 +1628,8 @@ static int ath_tx_setup_buffer(struct ieee80211_hw *hw, struct ath_buf *bf,
 		bf->bf_keyix = ATH9K_TXKEYIX_INVALID;
 	}
 
-	if (ieee80211_is_data_qos(fc) && (sc->sc_flags & SC_OP_TXAGGR))
+	if (ieee80211_is_data_qos(fc) && bf_isht(bf) &&
+	    (sc->sc_flags & SC_OP_TXAGGR))
 		assign_aggr_tid_seqno(skb, bf);
 
 	bf->bf_mpdu = skb;