Fix handling of shortgi: use the local configuration (and implicitly

device capabilities) to decide whether to use short gi.  Drivers
inspect ni_flags to decide whether to send a frame w/ short sgi.

3 files changed, 25 insertions, 2 deletions

diff --git a/sys/net80211/ieee80211_ddb.c b/sys/net80211/ieee80211_ddb.c
index 76a7119..6e83235 100644
--- a/sys/net80211/ieee80211_ddb.c
+++ b/sys/net80211/ieee80211_ddb.c
@@ -90,7 +90,7 @@ __FBSDID("$FreeBSD$");
 
 #define	IEEE80211_NODE_BITS \
 	"\20\1AUTH\2QOS\3ERP\5PWR_MGT\6AREF\7HT\10HTCOMPAT\11WPS\12TSN" \
-	"\13AMPDU_RX\14AMPDU_TX\15MIMO_PS\16MIMO_RTS\17RIFS"
+	"\13AMPDU_RX\14AMPDU_TX\15MIMO_PS\16MIMO_RTS\17RIFS\20SGI20\21SGI40"
 
 #define	IEEE80211_ERP_BITS \
 	"\20\1NON_ERP_PRESENT\2USE_PROTECTION\3LONG_PREAMBLE"
diff --git a/sys/net80211/ieee80211_ht.c b/sys/net80211/ieee80211_ht.c
index eef537b..321566b 100644
--- a/sys/net80211/ieee80211_ht.c
+++ b/sys/net80211/ieee80211_ht.c
@@ -1270,6 +1270,24 @@ htcap_update_mimo_ps(struct ieee80211_node *ni)
 }
 
 /*
+ * Update short GI state according to received htcap
+ * and local settings.
+ */
+static __inline void
+htcap_update_shortgi(struct ieee80211_node *ni)
+{
+	struct ieee80211vap *vap = ni->ni_vap;
+
+	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
+	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
+	    (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI20))
+		ni->ni_flags |= IEEE80211_NODE_SGI20;
+	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
+	    (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI40))
+		ni->ni_flags |= IEEE80211_NODE_SGI40;
+}
+
+/*
  * Parse and update HT-related state extracted from
  * the HT cap and info ie's.
  */
@@ -1284,6 +1302,7 @@ ieee80211_ht_updateparams(struct ieee80211_node *ni,
 	ieee80211_parse_htcap(ni, htcapie);
 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
 		htcap_update_mimo_ps(ni);
+	htcap_update_shortgi(ni);
 
 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
 		htinfoie += 4;
@@ -1322,6 +1341,7 @@ ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
 	ieee80211_parse_htcap(ni, htcapie);
 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
 		htcap_update_mimo_ps(ni);
+	htcap_update_shortgi(ni);
 
 	/* NB: honor operating mode constraint */
 	/* XXX 40 MHZ intolerant */
diff --git a/sys/net80211/ieee80211_node.h b/sys/net80211/ieee80211_node.h
index 045bd15..2aaec0a 100644
--- a/sys/net80211/ieee80211_node.h
+++ b/sys/net80211/ieee80211_node.h
@@ -115,6 +115,8 @@ struct ieee80211_node {
 #define	IEEE80211_NODE_MIMO_PS	0x001000	/* MIMO power save enabled */
 #define	IEEE80211_NODE_MIMO_RTS	0x002000	/* send RTS in MIMO PS */
 #define	IEEE80211_NODE_RIFS	0x004000	/* RIFS enabled */
+#define	IEEE80211_NODE_SGI20	0x008000	/* Short GI in HT20 enabled */
+#define	IEEE80211_NODE_SGI40	0x010000	/* Short GI in HT40 enabled */
 	uint16_t		ni_associd;	/* association ID */
 	uint16_t		ni_vlan;	/* vlan tag */
 	uint16_t		ni_txpower;	/* current transmit power */
@@ -199,7 +201,8 @@ MALLOC_DECLARE(M_80211_NODE_IE);
 #define	IEEE80211_NODE_HT_ALL \
 	(IEEE80211_NODE_HT | IEEE80211_NODE_HTCOMPAT | \
 	 IEEE80211_NODE_AMPDU | IEEE80211_NODE_MIMO_PS | \
-	 IEEE80211_NODE_MIMO_RTS | IEEE80211_NODE_RIFS)
+	 IEEE80211_NODE_MIMO_RTS | IEEE80211_NODE_RIFS | \
+	 IEEE80211_NODE_SGI20 | IEEE80211_NODE_SGI40)
 
 #define	IEEE80211_NODE_AID(ni)	IEEE80211_AID(ni->ni_associd)