ath9k: Assign seq# when mac80211 requests this

Use TX control flag IEEE80211_TX_CTL_ASSIGN_SEQ as a request to update
the seq# for the frames. This will likely require some further cleanup
to get seq# correctly for Beacons vs. other frames and also potentially
for multiple BSSes. Anyway, this is better than ending up sending out
most frames with seq# 0.

(This is a backport of patch w/ same title already in net-next-2.6.
It is verified to fix http://bugzilla.kernel.org/show_bug.cgi?id=11394
and it should be acceptable for -rc due to the driver being new
in 2.6.27.)
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/beacon.c

@@ -209,6 +209,7 @@ static struct ath_buf *ath_beacon_generate(struct ath_softc *sc, int if_id)
 	unsigned int curlen;
 	struct ath_txq *cabq;
 	struct ath_txq *mcastq;
+	struct ieee80211_tx_info *info;
 	avp = sc->sc_vaps[if_id];
 
 	mcastq = &avp->av_mcastq;
@@ -232,6 +233,18 @@ static struct ath_buf *ath_beacon_generate(struct ath_softc *sc, int if_id)
 	 */
 	curlen = skb->len;
 
+	info = IEEE80211_SKB_CB(skb);
+	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
+		/*
+		 * TODO: make sure the seq# gets assigned properly (vs. other
+		 * TX frames)
+		 */
+		struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+		sc->seq_no += 0x10;
+		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
+		hdr->seq_ctrl |= cpu_to_le16(sc->seq_no);
+	}
+
 	/* XXX: spin_lock_bh should not be used here, but sparse bitches
 	 * otherwise. We should fix sparse :) */
 	spin_lock_bh(&mcastq->axq_lock);

drivers/net/wireless/ath9k/core.h

@@ -992,6 +992,7 @@ struct ath_softc {
 	u32 sc_txintrperiod;	/* tx interrupt batching */
 	int sc_haltype2q[ATH9K_WME_AC_VO+1]; /* HAL WME	AC -> h/w qnum */
 	u32 sc_ant_tx[8];	/* recent tx frames/antenna */
+	u16 seq_no; /* TX sequence number */
 
 	/* Beacon */
 	struct ath9k_tx_queue_info sc_beacon_qi;

drivers/net/wireless/ath9k/main.c

@@ -369,6 +369,20 @@ static int ath9k_tx(struct ieee80211_hw *hw,
 {
 	struct ath_softc *sc = hw->priv;
 	int hdrlen, padsize;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+	/*
+	 * As a temporary workaround, assign seq# here; this will likely need
+	 * to be cleaned up to work better with Beacon transmission and virtual
+	 * BSSes.
+	 */
+	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
+		struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
+			sc->seq_no += 0x10;
+		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
+		hdr->seq_ctrl |= cpu_to_le16(sc->seq_no);
+	}
 
 	/* Add the padding after the header if this is not already done */
 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);