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add HT format to radiotap

PATCH New Johannes Berg 1 participant 3 messages May 10, 2012

Subsystems (2)
Networking drivers (wireless) mac80211
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Johannes Berg

author maintainer
#0 lore raw

cover add HT format to radiotap

The iwlwifi patch is only as RFC since I should push it through our internal tree first, the mac80211 patch allows us to add HT format to the MCS field in radiotap.

johannes

author maintainer
#1 lore raw

PATCH 1/2 mac80211: (selectively) add HT details in radiotap

From: Johannes Berg <[email protected]>

Add a flag for the HT format (mixed vs. greenfield) to allow drivers to report that on receive. Not all drivers will do that though, so allow drivers to set which radiotap MCS details they report.

Signed-off-by Johannes Berg <[email protected]>
---
 include/net/mac80211.h |   10 ++++++++++
 net/mac80211/main.c    |    3 +++
 net/mac80211/rx.c      |    6 +++---
 3 files changed, 16 insertions(+), 3 deletions(-)
net/mac80211/rx.c +3 -3
@@ -204,14 +204,14 @@ ieee80211_add_rx_radiotap_header(struct
 
 	if (status->flag & RX_FLAG_HT) {
 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
-		*pos++ = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
-			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
-			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
+		*pos++ = local->hw.radiotap_mcs_details;
 		*pos = 0;
 		if (status->flag & RX_FLAG_SHORT_GI)
 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
 		if (status->flag & RX_FLAG_40MHZ)
 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
+		if (status->flag & RX_FLAG_HT_GF)
+			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 		pos++;
 		*pos++ = status->rate_idx;
 	}
include/net/mac80211.h +10 -0
@@ -667,6 +667,9 @@ ieee80211_tx_info_clear_status(struct ie
  * @RX_FLAG_SHORT_GI: Short guard interval was used
  * @RX_FLAG_NO_SIGNAL_VAL: The signal strength value is not present.
  *	Valid only for data frames (mainly A-MPDU)
+ * @RX_FLAG_HT_GF: This frame was received in a HT-greenfield transmission, if
+ *	the driver fills this value it should add %IEEE80211_RADIOTAP_MCS_HAVE_FMT
+ *	to hw.radiotap_mcs_details to advertise that fact
  */
 enum mac80211_rx_flags {
 	RX_FLAG_MMIC_ERROR	= 1<<0,

@@ -681,6 +684,7 @@ enum mac80211_rx_flags {
 	RX_FLAG_40MHZ		= 1<<10,
 	RX_FLAG_SHORT_GI	= 1<<11,
 	RX_FLAG_NO_SIGNAL_VAL	= 1<<12,
+	RX_FLAG_HT_GF		= 1<<13,
 };
 
 /**

@@ -1288,6 +1292,11 @@ enum ieee80211_hw_flags {
  *
  * @offchannel_tx_hw_queue: HW queue ID to use for offchannel TX
  *	(if %IEEE80211_HW_QUEUE_CONTROL is set)
+ *
+ * @radiotap_mcs_details: lists which MCS information can the HW
+ *	reports, by default it is set to _MCS, _GI and _BW but doesn't
+ *	include _FMT. Use %IEEE80211_RADIOTAP_MCS_HAVE_* values, only
+ *	adding _BW is supported today.
  */
 struct ieee80211_hw {
 	struct ieee80211_conf conf;

@@ -1309,6 +1318,7 @@ struct ieee80211_hw {
 	u8 max_rx_aggregation_subframes;
 	u8 max_tx_aggregation_subframes;
 	u8 offchannel_tx_hw_queue;
+	u8 radiotap_mcs_details;
 };
 
 /**
net/mac80211/main.c +3 -0
@@ -597,6 +597,9 @@ struct ieee80211_hw *ieee80211_alloc_hw(
 	local->hw.offchannel_tx_hw_queue = IEEE80211_INVAL_HW_QUEUE;
 	local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
 	local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
+	local->hw.radiotap_mcs_details = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
+					 IEEE80211_RADIOTAP_MCS_HAVE_GI |
+					 IEEE80211_RADIOTAP_MCS_HAVE_BW;
 	local->user_power_level = -1;
 	wiphy->ht_capa_mod_mask = &mac80211_ht_capa_mod_mask;
author maintainer
#2 lore raw

RFC 2/2 iwlwifi: give HT format to mac80211/radiotap

In reply to Johannes Berg

From: Johannes Berg <[email protected]>

We know whether we received a frame in GF format
or not, add it to the radiotap information.

Signed-off-by Johannes Berg <[email protected]>
---
 drivers/net/wireless/iwlwifi/iwl-agn-rx.c   |    2 ++
 drivers/net/wireless/iwlwifi/iwl-mac80211.c |    2 ++
 2 files changed, 4 insertions(+)
drivers/net/wireless/iwlwifi/iwl-agn-rx.c +2 -0
@@ -1007,6 +1007,8 @@ static int iwlagn_rx_reply_rx(struct iwl
 		rx_status.flag |= RX_FLAG_40MHZ;
 	if (rate_n_flags & RATE_MCS_SGI_MSK)
 		rx_status.flag |= RX_FLAG_SHORT_GI;
+	if (rate_n_flags & RATE_MCS_GF_MSK)
+		rx_status.flag |= RX_FLAG_HT_GF;
 
 	iwlagn_pass_packet_to_mac80211(priv, header, len, ampdu_status,
 				    rxb, &rx_status);
drivers/net/wireless/iwlwifi/iwl-mac80211.c +2 -0
@@ -38,6 +38,7 @@
 #include <linux/etherdevice.h>
 #include <linux/if_arp.h>
 
+#include <net/ieee80211_radiotap.h>
 #include <net/mac80211.h>
 
 #include <asm/div64.h>

@@ -154,6 +155,7 @@ int iwlagn_mac_setup_register(struct iwl
 		    IEEE80211_HW_SCAN_WHILE_IDLE;
 
 	hw->offchannel_tx_hw_queue = IWL_AUX_QUEUE;
+	hw->radiotap_mcs_details |= IEEE80211_RADIOTAP_MCS_HAVE_FMT;
 
 	/*
 	 * Including the following line will crash some AP's.  This