mac80211: support VHT rates in TX info

To achieve this, limit the number of retries to
31 (instead of 255) and use the three bits that
are then free for VHT flags.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -499,9 +499,14 @@ enum mac80211_tx_control_flags {
  *	This is set if the current BSS requires ERP protection.
  * @IEEE80211_TX_RC_USE_SHORT_PREAMBLE: Use short preamble.
  * @IEEE80211_TX_RC_MCS: HT rate.
+ * @IEEE80211_TX_RC_VHT_MCS: VHT MCS rate, in this case the idx field is split
+ *	into a higher 4 bits (Nss) and lower 4 bits (MCS number)
  * @IEEE80211_TX_RC_GREEN_FIELD: Indicates whether this rate should be used in
  *	Greenfield mode.
  * @IEEE80211_TX_RC_40_MHZ_WIDTH: Indicates if the Channel Width should be 40 MHz.
+ * @IEEE80211_TX_RC_80_MHZ_WIDTH: Indicates 80 MHz transmission
+ * @IEEE80211_TX_RC_160_MHZ_WIDTH: Indicates 160 MHz transmission
+ *	(80+80 isn't supported yet)
  * @IEEE80211_TX_RC_DUP_DATA: The frame should be transmitted on both of the
  *	adjacent 20 MHz channels, if the current channel type is
  *	NL80211_CHAN_HT40MINUS or NL80211_CHAN_HT40PLUS.
@@ -512,12 +517,15 @@ enum mac80211_rate_control_flags {
 	IEEE80211_TX_RC_USE_CTS_PROTECT		= BIT(1),
 	IEEE80211_TX_RC_USE_SHORT_PREAMBLE	= BIT(2),
 
-	/* rate index is an MCS rate number instead of an index */
+	/* rate index is an HT/VHT MCS instead of an index */
 	IEEE80211_TX_RC_MCS			= BIT(3),
 	IEEE80211_TX_RC_GREEN_FIELD		= BIT(4),
 	IEEE80211_TX_RC_40_MHZ_WIDTH		= BIT(5),
 	IEEE80211_TX_RC_DUP_DATA		= BIT(6),
 	IEEE80211_TX_RC_SHORT_GI		= BIT(7),
+	IEEE80211_TX_RC_VHT_MCS			= BIT(8),
+	IEEE80211_TX_RC_80_MHZ_WIDTH		= BIT(9),
+	IEEE80211_TX_RC_160_MHZ_WIDTH		= BIT(10),
 };
 
 
@@ -560,10 +568,32 @@ enum mac80211_rate_control_flags {
  */
 struct ieee80211_tx_rate {
 	s8 idx;
-	u8 count;
-	u8 flags;
+	u16 count:5,
+	    flags:11;
 } __packed;
 
+#define IEEE80211_MAX_TX_RETRY		31
+
+static inline void ieee80211_rate_set_vht(struct ieee80211_tx_rate *rate,
+					  u8 mcs, u8 nss)
+{
+	WARN_ON(mcs & ~0xF);
+	WARN_ON(nss & ~0x7);
+	rate->idx = (nss << 4) | mcs;
+}
+
+static inline u8
+ieee80211_rate_get_vht_mcs(const struct ieee80211_tx_rate *rate)
+{
+	return rate->idx & 0xF;
+}
+
+static inline u8
+ieee80211_rate_get_vht_nss(const struct ieee80211_tx_rate *rate)
+{
+	return rate->idx >> 4;
+}
+
 /**
  * struct ieee80211_tx_info - skb transmit information
  *

net/mac80211/cfg.c

@@ -370,31 +370,32 @@ static int ieee80211_config_default_mgmt_key(struct wiphy *wiphy,
 	return 0;
 }
 
-static void rate_idx_to_bitrate(struct rate_info *rate, struct sta_info *sta, int idx)
-{
-	enum ieee80211_band band = ieee80211_get_sdata_band(sta->sdata);
-
-	if (!(rate->flags & RATE_INFO_FLAGS_MCS) &&
-	    !(rate->flags & RATE_INFO_FLAGS_VHT_MCS)) {
-		struct ieee80211_supported_band *sband;
-		sband = sta->local->hw.wiphy->bands[band];
-		rate->legacy = sband->bitrates[idx].bitrate;
-	} else
-		rate->mcs = idx;
-}
-
 void sta_set_rate_info_tx(struct sta_info *sta,
 			  const struct ieee80211_tx_rate *rate,
 			  struct rate_info *rinfo)
 {
 	rinfo->flags = 0;
-	if (rate->flags & IEEE80211_TX_RC_MCS)
+	if (rate->flags & IEEE80211_TX_RC_MCS) {
 		rinfo->flags |= RATE_INFO_FLAGS_MCS;
+		rinfo->mcs = rate->idx;
+	} else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) {
+		rinfo->flags |= RATE_INFO_FLAGS_VHT_MCS;
+		rinfo->mcs = ieee80211_rate_get_vht_mcs(rate);
+		rinfo->nss = ieee80211_rate_get_vht_nss(rate);
+	} else {
+		struct ieee80211_supported_band *sband;
+		sband = sta->local->hw.wiphy->bands[
+				ieee80211_get_sdata_band(sta->sdata)];
+		rinfo->legacy = sband->bitrates[rate->idx].bitrate;
+	}
 	if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 		rinfo->flags |= RATE_INFO_FLAGS_40_MHZ_WIDTH;
+	if (rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
+		rinfo->flags |= RATE_INFO_FLAGS_80_MHZ_WIDTH;
+	if (rate->flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
+		rinfo->flags |= RATE_INFO_FLAGS_160_MHZ_WIDTH;
 	if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
 		rinfo->flags |= RATE_INFO_FLAGS_SHORT_GI;
-	rate_idx_to_bitrate(rinfo, sta, rate->idx);
 }
 
 static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
@@ -2003,10 +2004,16 @@ static int ieee80211_set_wiphy_params(struct wiphy *wiphy, u32 changed)
 			return err;
 	}
 
-	if (changed & WIPHY_PARAM_RETRY_SHORT)
+	if (changed & WIPHY_PARAM_RETRY_SHORT) {
+		if (wiphy->retry_short > IEEE80211_MAX_TX_RETRY)
+			return -EINVAL;
 		local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
-	if (changed & WIPHY_PARAM_RETRY_LONG)
+	}
+	if (changed & WIPHY_PARAM_RETRY_LONG) {
+		if (wiphy->retry_long > IEEE80211_MAX_TX_RETRY)
+			return -EINVAL;
 		local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
+	}
 	if (changed &
 	    (WIPHY_PARAM_RETRY_SHORT | WIPHY_PARAM_RETRY_LONG))
 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_RETRY_LIMITS);