nl80211: Add signal strength and bandwith to nl80211station info

This patch adds signal strength and transmission bitrate to the station_info of nl80211. Signed-off-by: Henning Rogge <rogge@fgan.de> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>

nl80211: Add signal strength and bandwith to nl80211station info
This patch adds signal strength and transmission bitrate to the station_info of nl80211. Signed-off-by: Henning Rogge <rogge@fgan.de> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Henning Rogge · John W. Linville
1 parent 221b3d60cb
Showing 4 changed files with 152 additions and 2 deletions Side-by-side Diff
include/linux/nl80211.h
include/net/cfg80211.h
net/mac80211/cfg.c
net/wireless/nl80211.c
@@ -425,6 +425,32 @@
 };
  
 /**
+ * enum nl80211_rate_info - bitrate information
+ *
+ * These attribute types are used with %NL80211_STA_INFO_TXRATE
+ * when getting information about the bitrate of a station.
+ *
+ * @__NL80211_RATE_INFO_INVALID: attribute number 0 is reserved
+ * @NL80211_RATE_INFO_BITRATE: total bitrate (u16, 100kbit/s)
+ * @NL80211_RATE_INFO_MCS: mcs index for 802.11n (u8)
+ * @NL80211_RATE_INFO_40_MHZ_WIDTH: 40 Mhz dualchannel bitrate
+ * @NL80211_RATE_INFO_SHORT_GI: 400ns guard interval
+ * @NL80211_RATE_INFO_MAX: highest rate_info number currently defined
+ * @__NL80211_RATE_INFO_AFTER_LAST: internal use
+ */
+enum nl80211_rate_info {
+	__NL80211_RATE_INFO_INVALID,
+	NL80211_RATE_INFO_BITRATE,
+	NL80211_RATE_INFO_MCS,
+	NL80211_RATE_INFO_40_MHZ_WIDTH,
+	NL80211_RATE_INFO_SHORT_GI,
+
+	/* keep last */
+	__NL80211_RATE_INFO_AFTER_LAST,
+	NL80211_RATE_INFO_MAX = __NL80211_RATE_INFO_AFTER_LAST - 1
+};
+
+/**
  * enum nl80211_sta_info - station information
  *
  * These attribute types are used with %NL80211_ATTR_STA_INFO
@@ -436,6 +462,9 @@
  * @NL80211_STA_INFO_TX_BYTES: total transmitted bytes (u32, to this station)
  * @__NL80211_STA_INFO_AFTER_LAST: internal
  * @NL80211_STA_INFO_MAX: highest possible station info attribute
+ * @NL80211_STA_INFO_SIGNAL: signal strength of last received PPDU (u8, dBm)
+ * @NL80211_STA_INFO_TX_BITRATE: current unicast tx rate, nested attribute
+ * 	containing info as possible, see &enum nl80211_sta_info_txrate.
  */
 enum nl80211_sta_info {
 	__NL80211_STA_INFO_INVALID,
@@ -445,6 +474,8 @@
 	NL80211_STA_INFO_LLID,
 	NL80211_STA_INFO_PLID,
 	NL80211_STA_INFO_PLINK_STATE,
+	NL80211_STA_INFO_SIGNAL,
+	NL80211_STA_INFO_TX_BITRATE,
  
 	/* keep last */
 	__NL80211_STA_INFO_AFTER_LAST,
@@ -169,6 +169,9 @@
  * @STATION_INFO_LLID: @llid filled
  * @STATION_INFO_PLID: @plid filled
  * @STATION_INFO_PLINK_STATE: @plink_state filled
+ * @STATION_INFO_SIGNAL: @signal filled
+ * @STATION_INFO_TX_BITRATE: @tx_bitrate fields are filled
+ *  (tx_bitrate, tx_bitrate_flags and tx_bitrate_mcs)
  */
 enum station_info_flags {
 	STATION_INFO_INACTIVE_TIME	= 1<<0,
  
@@ -177,9 +180,42 @@
 	STATION_INFO_LLID		= 1<<3,
 	STATION_INFO_PLID		= 1<<4,
 	STATION_INFO_PLINK_STATE	= 1<<5,
+	STATION_INFO_SIGNAL		= 1<<6,
+	STATION_INFO_TX_BITRATE		= 1<<7,
 };
  
 /**
+ * enum station_info_rate_flags - bitrate info flags
+ *
+ * Used by the driver to indicate the specific rate transmission
+ * type for 802.11n transmissions.
+ *
+ * @RATE_INFO_FLAGS_MCS: @tx_bitrate_mcs filled
+ * @RATE_INFO_FLAGS_40_MHZ_WIDTH: 40 Mhz width transmission
+ * @RATE_INFO_FLAGS_SHORT_GI: 400ns guard interval
+ */
+enum rate_info_flags {
+	RATE_INFO_FLAGS_MCS		= 1<<0,
+	RATE_INFO_FLAGS_40_MHZ_WIDTH	= 1<<1,
+	RATE_INFO_FLAGS_SHORT_GI	= 1<<2,
+};
+
+/**
+ * struct rate_info - bitrate information
+ *
+ * Information about a receiving or transmitting bitrate
+ *
+ * @flags: bitflag of flags from &enum rate_info_flags
+ * @mcs: mcs index if struct describes a 802.11n bitrate
+ * @legacy: bitrate in 100kbit/s for 802.11abg
+ */
+struct rate_info {
+	u8 flags;
+	u8 mcs;
+	u16 legacy;
+};
+
+/**
  * struct station_info - station information
  *
  * Station information filled by driver for get_station() and dump_station.
@@ -191,6 +227,8 @@
  * @llid: mesh local link id
  * @plid: mesh peer link id
  * @plink_state: mesh peer link state
+ * @signal: signal strength of last received packet in dBm
+ * @txrate: current unicast bitrate to this station
  */
 struct station_info {
 	u32 filled;
@@ -200,6 +238,8 @@
 	u16 llid;
 	u16 plid;
 	u8 plink_state;
+	s8 signal;
+	struct rate_info txrate;
 };
  
 /**
@@ -310,11 +310,34 @@
  
 	sinfo->filled = STATION_INFO_INACTIVE_TIME |
 			STATION_INFO_RX_BYTES |
-			STATION_INFO_TX_BYTES;
+			STATION_INFO_TX_BYTES |
+			STATION_INFO_TX_BITRATE;
  
 	sinfo->inactive_time = jiffies_to_msecs(jiffies - sta->last_rx);
 	sinfo->rx_bytes = sta->rx_bytes;
 	sinfo->tx_bytes = sta->tx_bytes;
+
+	if (sta->local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
+		sinfo->filled |= STATION_INFO_SIGNAL;
+		sinfo->signal = (s8)sta->last_signal;
+	}
+
+	sinfo->txrate.flags = 0;
+	if (sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)
+		sinfo->txrate.flags |= RATE_INFO_FLAGS_MCS;
+	if (sta->last_tx_rate.flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
+		sinfo->txrate.flags |= RATE_INFO_FLAGS_40_MHZ_WIDTH;
+	if (sta->last_tx_rate.flags & IEEE80211_TX_RC_SHORT_GI)
+		sinfo->txrate.flags |= RATE_INFO_FLAGS_SHORT_GI;
+
+	if (!(sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)) {
+		struct ieee80211_supported_band *sband;
+		sband = sta->local->hw.wiphy->bands[
+				sta->local->hw.conf.channel->band];
+		sinfo->txrate.legacy =
+			sband->bitrates[sta->last_tx_rate.idx].bitrate;
+	} else
+		sinfo->txrate.mcs = sta->last_tx_rate.idx;
  
 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
 #ifdef CONFIG_MAC80211_MESH
@@ -1091,12 +1091,46 @@
 	return 0;
 }
  
+static u16 nl80211_calculate_bitrate(struct rate_info *rate)
+{
+	int modulation, streams, bitrate;
+
+	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
+		return rate->legacy;
+
+	/* the formula below does only work for MCS values smaller than 32 */
+	if (rate->mcs >= 32)
+		return 0;
+
+	modulation = rate->mcs & 7;
+	streams = (rate->mcs >> 3) + 1;
+
+	bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
+			13500000 : 6500000;
+
+	if (modulation < 4)
+		bitrate *= (modulation + 1);
+	else if (modulation == 4)
+		bitrate *= (modulation + 2);
+	else
+		bitrate *= (modulation + 3);
+
+	bitrate *= streams;
+
+	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
+		bitrate = (bitrate / 9) * 10;
+
+	/* do NOT round down here */
+	return (bitrate + 50000) / 100000;
+}
+
 static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
 				int flags, struct net_device *dev,
 				u8 *mac_addr, struct station_info *sinfo)
 {
 	void *hdr;
-	struct nlattr *sinfoattr;
+	struct nlattr *sinfoattr, *txrate;
+	u16 bitrate;
  
 	hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_STATION);
 	if (!hdr)
  
@@ -1126,7 +1160,29 @@
 	if (sinfo->filled & STATION_INFO_PLINK_STATE)
 		NLA_PUT_U8(msg, NL80211_STA_INFO_PLINK_STATE,
 			    sinfo->plink_state);
+	if (sinfo->filled & STATION_INFO_SIGNAL)
+		NLA_PUT_U8(msg, NL80211_STA_INFO_SIGNAL,
+			   sinfo->signal);
+	if (sinfo->filled & STATION_INFO_TX_BITRATE) {
+		txrate = nla_nest_start(msg, NL80211_STA_INFO_TX_BITRATE);
+		if (!txrate)
+			goto nla_put_failure;
  
+		/* nl80211_calculate_bitrate will return 0 for mcs >= 32 */
+		bitrate = nl80211_calculate_bitrate(&sinfo->txrate);
+		if (bitrate > 0)
+			NLA_PUT_U16(msg, NL80211_RATE_INFO_BITRATE, bitrate);
+
+		if (sinfo->txrate.flags & RATE_INFO_FLAGS_MCS)
+			NLA_PUT_U8(msg, NL80211_RATE_INFO_MCS,
+				    sinfo->txrate.mcs);
+		if (sinfo->txrate.flags & RATE_INFO_FLAGS_40_MHZ_WIDTH)
+			NLA_PUT_FLAG(msg, NL80211_RATE_INFO_40_MHZ_WIDTH);
+		if (sinfo->txrate.flags & RATE_INFO_FLAGS_SHORT_GI)
+			NLA_PUT_FLAG(msg, NL80211_RATE_INFO_SHORT_GI);
+
+		nla_nest_end(msg, txrate);
+	}
 	nla_nest_end(msg, sinfoattr);
  
 	return genlmsg_end(msg, hdr);
...	...	@@ -425,6 +425,32 @@
425	425	};
426	426
427	427	/**
	428	+ * enum nl80211_rate_info - bitrate information
	429	+ *
	430	+ * These attribute types are used with %NL80211_STA_INFO_TXRATE
	431	+ * when getting information about the bitrate of a station.
	432	+ *
	433	+ * @__NL80211_RATE_INFO_INVALID: attribute number 0 is reserved
	434	+ * @NL80211_RATE_INFO_BITRATE: total bitrate (u16, 100kbit/s)
	435	+ * @NL80211_RATE_INFO_MCS: mcs index for 802.11n (u8)
	436	+ * @NL80211_RATE_INFO_40_MHZ_WIDTH: 40 Mhz dualchannel bitrate
	437	+ * @NL80211_RATE_INFO_SHORT_GI: 400ns guard interval
	438	+ * @NL80211_RATE_INFO_MAX: highest rate_info number currently defined
	439	+ * @__NL80211_RATE_INFO_AFTER_LAST: internal use
	440	+ */
	441	+enum nl80211_rate_info {
	442	+ __NL80211_RATE_INFO_INVALID,
	443	+ NL80211_RATE_INFO_BITRATE,
	444	+ NL80211_RATE_INFO_MCS,
	445	+ NL80211_RATE_INFO_40_MHZ_WIDTH,
	446	+ NL80211_RATE_INFO_SHORT_GI,
	447	+
	448	+ /* keep last */
	449	+ __NL80211_RATE_INFO_AFTER_LAST,
	450	+ NL80211_RATE_INFO_MAX = __NL80211_RATE_INFO_AFTER_LAST - 1
	451	+};
	452	+
	453	+/**
428	454	* enum nl80211_sta_info - station information
429	455	*
430	456	* These attribute types are used with %NL80211_ATTR_STA_INFO
...	...	@@ -436,6 +462,9 @@
436	462	* @NL80211_STA_INFO_TX_BYTES: total transmitted bytes (u32, to this station)
437	463	* @__NL80211_STA_INFO_AFTER_LAST: internal
438	464	* @NL80211_STA_INFO_MAX: highest possible station info attribute
	465	+ * @NL80211_STA_INFO_SIGNAL: signal strength of last received PPDU (u8, dBm)
	466	+ * @NL80211_STA_INFO_TX_BITRATE: current unicast tx rate, nested attribute
	467	+ * containing info as possible, see &enum nl80211_sta_info_txrate.
439	468	*/
440	469	enum nl80211_sta_info {
441	470	__NL80211_STA_INFO_INVALID,
...	...	@@ -445,6 +474,8 @@
445	474	NL80211_STA_INFO_LLID,
446	475	NL80211_STA_INFO_PLID,
447	476	NL80211_STA_INFO_PLINK_STATE,
	477	+ NL80211_STA_INFO_SIGNAL,
	478	+ NL80211_STA_INFO_TX_BITRATE,
448	479
449	480	/* keep last */
450	481	__NL80211_STA_INFO_AFTER_LAST,
...	...	@@ -169,6 +169,9 @@
169	169	* @STATION_INFO_LLID: @llid filled
170	170	* @STATION_INFO_PLID: @plid filled
171	171	* @STATION_INFO_PLINK_STATE: @plink_state filled
	172	+ * @STATION_INFO_SIGNAL: @signal filled
	173	+ * @STATION_INFO_TX_BITRATE: @tx_bitrate fields are filled
	174	+ * (tx_bitrate, tx_bitrate_flags and tx_bitrate_mcs)
172	175	*/
173	176	enum station_info_flags {
174	177	STATION_INFO_INACTIVE_TIME = 1<<0,
175	178
...	...	@@ -177,9 +180,42 @@
177	180	STATION_INFO_LLID = 1<<3,
178	181	STATION_INFO_PLID = 1<<4,
179	182	STATION_INFO_PLINK_STATE = 1<<5,
	183	+ STATION_INFO_SIGNAL = 1<<6,
	184	+ STATION_INFO_TX_BITRATE = 1<<7,
180	185	};
181	186
182	187	/**
	188	+ * enum station_info_rate_flags - bitrate info flags
	189	+ *
	190	+ * Used by the driver to indicate the specific rate transmission
	191	+ * type for 802.11n transmissions.
	192	+ *
	193	+ * @RATE_INFO_FLAGS_MCS: @tx_bitrate_mcs filled
	194	+ * @RATE_INFO_FLAGS_40_MHZ_WIDTH: 40 Mhz width transmission
	195	+ * @RATE_INFO_FLAGS_SHORT_GI: 400ns guard interval
	196	+ */
	197	+enum rate_info_flags {
	198	+ RATE_INFO_FLAGS_MCS = 1<<0,
	199	+ RATE_INFO_FLAGS_40_MHZ_WIDTH = 1<<1,
	200	+ RATE_INFO_FLAGS_SHORT_GI = 1<<2,
	201	+};
	202	+
	203	+/**
	204	+ * struct rate_info - bitrate information
	205	+ *
	206	+ * Information about a receiving or transmitting bitrate
	207	+ *
	208	+ * @flags: bitflag of flags from &enum rate_info_flags
	209	+ * @mcs: mcs index if struct describes a 802.11n bitrate
	210	+ * @legacy: bitrate in 100kbit/s for 802.11abg
	211	+ */
	212	+struct rate_info {
	213	+ u8 flags;
	214	+ u8 mcs;
	215	+ u16 legacy;
	216	+};
	217	+
	218	+/**
183	219	* struct station_info - station information
184	220	*
185	221	* Station information filled by driver for get_station() and dump_station.
...	...	@@ -191,6 +227,8 @@
191	227	* @llid: mesh local link id
192	228	* @plid: mesh peer link id
193	229	* @plink_state: mesh peer link state
	230	+ * @signal: signal strength of last received packet in dBm
	231	+ * @txrate: current unicast bitrate to this station
194	232	*/
195	233	struct station_info {
196	234	u32 filled;
...	...	@@ -200,6 +238,8 @@
200	238	u16 llid;
201	239	u16 plid;
202	240	u8 plink_state;
	241	+ s8 signal;
	242	+ struct rate_info txrate;
203	243	};
204	244
205	245	/**
...	...	@@ -310,11 +310,34 @@
310	310
311	311	sinfo->filled = STATION_INFO_INACTIVE_TIME \|
312	312	STATION_INFO_RX_BYTES \|
313		- STATION_INFO_TX_BYTES;
	313	+ STATION_INFO_TX_BYTES \|
	314	+ STATION_INFO_TX_BITRATE;
314	315
315	316	sinfo->inactive_time = jiffies_to_msecs(jiffies - sta->last_rx);
316	317	sinfo->rx_bytes = sta->rx_bytes;
317	318	sinfo->tx_bytes = sta->tx_bytes;
	319	+
	320	+ if (sta->local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
	321	+ sinfo->filled \|= STATION_INFO_SIGNAL;
	322	+ sinfo->signal = (s8)sta->last_signal;
	323	+ }
	324	+
	325	+ sinfo->txrate.flags = 0;
	326	+ if (sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)
	327	+ sinfo->txrate.flags \|= RATE_INFO_FLAGS_MCS;
	328	+ if (sta->last_tx_rate.flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
	329	+ sinfo->txrate.flags \|= RATE_INFO_FLAGS_40_MHZ_WIDTH;
	330	+ if (sta->last_tx_rate.flags & IEEE80211_TX_RC_SHORT_GI)
	331	+ sinfo->txrate.flags \|= RATE_INFO_FLAGS_SHORT_GI;
	332	+
	333	+ if (!(sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)) {
	334	+ struct ieee80211_supported_band *sband;
	335	+ sband = sta->local->hw.wiphy->bands[
	336	+ sta->local->hw.conf.channel->band];
	337	+ sinfo->txrate.legacy =
	338	+ sband->bitrates[sta->last_tx_rate.idx].bitrate;
	339	+ } else
	340	+ sinfo->txrate.mcs = sta->last_tx_rate.idx;
318	341
319	342	if (ieee80211_vif_is_mesh(&sdata->vif)) {
320	343	#ifdef CONFIG_MAC80211_MESH
...	...	@@ -1091,12 +1091,46 @@
1091	1091	return 0;
1092	1092	}
1093	1093
	1094	+static u16 nl80211_calculate_bitrate(struct rate_info *rate)
	1095	+{
	1096	+ int modulation, streams, bitrate;
	1097	+
	1098	+ if (!(rate->flags & RATE_INFO_FLAGS_MCS))
	1099	+ return rate->legacy;
	1100	+
	1101	+ /* the formula below does only work for MCS values smaller than 32 */
	1102	+ if (rate->mcs >= 32)
	1103	+ return 0;
	1104	+
	1105	+ modulation = rate->mcs & 7;
	1106	+ streams = (rate->mcs >> 3) + 1;
	1107	+
	1108	+ bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
	1109	+ 13500000 : 6500000;
	1110	+
	1111	+ if (modulation < 4)
	1112	+ bitrate *= (modulation + 1);
	1113	+ else if (modulation == 4)
	1114	+ bitrate *= (modulation + 2);
	1115	+ else
	1116	+ bitrate *= (modulation + 3);
	1117	+
	1118	+ bitrate *= streams;
	1119	+
	1120	+ if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
	1121	+ bitrate = (bitrate / 9) * 10;
	1122	+
	1123	+ /* do NOT round down here */
	1124	+ return (bitrate + 50000) / 100000;
	1125	+}
	1126	+
1094	1127	static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
1095	1128	int flags, struct net_device *dev,
1096	1129	u8 mac_addr, struct station_info sinfo)
1097	1130	{
1098	1131	void *hdr;
1099		- struct nlattr *sinfoattr;
	1132	+ struct nlattr sinfoattr, txrate;
	1133	+ u16 bitrate;
1100	1134
1101	1135	hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_STATION);
1102	1136	if (!hdr)
1103	1137
...	...	@@ -1126,7 +1160,29 @@
1126	1160	if (sinfo->filled & STATION_INFO_PLINK_STATE)
1127	1161	NLA_PUT_U8(msg, NL80211_STA_INFO_PLINK_STATE,
1128	1162	sinfo->plink_state);
	1163	+ if (sinfo->filled & STATION_INFO_SIGNAL)
	1164	+ NLA_PUT_U8(msg, NL80211_STA_INFO_SIGNAL,
	1165	+ sinfo->signal);
	1166	+ if (sinfo->filled & STATION_INFO_TX_BITRATE) {
	1167	+ txrate = nla_nest_start(msg, NL80211_STA_INFO_TX_BITRATE);
	1168	+ if (!txrate)
	1169	+ goto nla_put_failure;
1129	1170
	1171	+ /* nl80211_calculate_bitrate will return 0 for mcs >= 32 */
	1172	+ bitrate = nl80211_calculate_bitrate(&sinfo->txrate);
	1173	+ if (bitrate > 0)
	1174	+ NLA_PUT_U16(msg, NL80211_RATE_INFO_BITRATE, bitrate);
	1175	+
	1176	+ if (sinfo->txrate.flags & RATE_INFO_FLAGS_MCS)
	1177	+ NLA_PUT_U8(msg, NL80211_RATE_INFO_MCS,
	1178	+ sinfo->txrate.mcs);
	1179	+ if (sinfo->txrate.flags & RATE_INFO_FLAGS_40_MHZ_WIDTH)
	1180	+ NLA_PUT_FLAG(msg, NL80211_RATE_INFO_40_MHZ_WIDTH);
	1181	+ if (sinfo->txrate.flags & RATE_INFO_FLAGS_SHORT_GI)
	1182	+ NLA_PUT_FLAG(msg, NL80211_RATE_INFO_SHORT_GI);
	1183	+
	1184	+ nla_nest_end(msg, txrate);
	1185	+ }
1130	1186	nla_nest_end(msg, sinfoattr);
1131	1187
1132	1188	return genlmsg_end(msg, hdr);