Fill hc_mcsset completely.

Contrary to the rateset information in legacy frames the MCS Set
field also contains TX capability information in cases where the
number of available TX and RX spartial streams differ. Because a
rateset doesn't contain that information we have to pull the
those directly from the hardware capabilities.

1 files changed, 42 insertions, 14 deletions

diff --git a/sys/net80211/ieee80211_ht.c b/sys/net80211/ieee80211_ht.c
index 9fedc00..5b8c248 100644
--- a/sys/net80211/ieee80211_ht.c
+++ b/sys/net80211/ieee80211_ht.c
@@ -2422,21 +2422,49 @@ ht_send_action_ht_txchwidth(struct ieee80211_node *ni,
 #undef ADDSHORT
 
 /*
- * Construct the MCS bit mask for inclusion
- * in an HT information element.
+ * Construct the MCS bit mask for inclusion in an HT capabilities
+ * information element.
  */
-static void 
-ieee80211_set_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
+static void
+ieee80211_set_mcsset(struct ieee80211com *ic, uint8_t *frm)
 {
 	int i;
+	uint8_t txparams;
 
-	for (i = 0; i < rs->rs_nrates; i++) {
-		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
-		if (r < IEEE80211_HTRATE_MAXSIZE) {	/* XXX? */
-			/* NB: this assumes a particular implementation */
-			setbit(frm, r);
+	KASSERT((ic->ic_rxstream > 0 && ic->ic_rxstream <= 4),
+	    ("ic_rxstream %d out of range", ic->ic_rxstream));
+	KASSERT((ic->ic_txstream > 0 && ic->ic_txstream <= 4),
+	    ("ic_txstream %d out of range", ic->ic_txstream));
+
+	for (i = 0; i < ic->ic_rxstream * 8; i++)
+		setbit(frm, i);
+	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
+	    (ic->ic_htcaps & IEEE80211_HTC_RXMCS32))
+		setbit(frm, 32);
+	if (ic->ic_htcaps & IEEE80211_HTC_RXUNEQUAL) {
+		if (ic->ic_rxstream >= 2) {
+			for (i = 33; i <= 38; i++)
+				setbit(frm, i);
+		}
+		if (ic->ic_rxstream >= 3) {
+			for (i = 39; i <= 52; i++)
+				setbit(frm, i);
+		}
+		if (ic->ic_txstream >= 4) {
+			for (i = 53; i <= 76; i++)
+				setbit(frm, i);
 		}
 	}
+
+	if (ic->ic_rxstream != ic->ic_txstream) {
+		txparams = 0x1;			/* TX MCS set defined */
+		txparams |= 0x2;		/* TX RX MCS not equal */
+		txparams |= (ic->ic_txstream - 1) << 2;	/* num TX streams */
+		if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL)
+			txparams |= 0x16;	/* TX unequal modulation sup */
+	} else
+		txparams = 0;
+	frm[12] = txparams;
 }
 
 /*
@@ -2502,12 +2530,12 @@ ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
 
 	/* supported MCS set */
 	/*
-	 * XXX it would better to get the rate set from ni_htrates
-	 * so we can restrict it but for sta mode ni_htrates isn't
-	 * setup when we're called to form an AssocReq frame so for
-	 * now we're restricted to the default HT rate set.
+	 * XXX: For sta mode the rate set should be restricted based
+	 * on the AP's capabilities, but ni_htrates isn't setup when
+	 * we're called to form an AssocReq frame so for now we're
+	 * restricted to the device capabilities.
 	 */
-	ieee80211_set_htrates(frm, &ieee80211_rateset_11n);
+	ieee80211_set_mcsset(ni->ni_ic, frm);
 
 	frm += __offsetof(struct ieee80211_ie_htcap, hc_extcap) -
 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);