[RFC PATCH 3/3] mac80211: add support connection monitor in hardware

[Kalle Valo <kalle.valo@iki.fi>]

From: Kalle Valo <kalle.valo@nokia.com>

wl1271 has a feature so that it handles the connection monitor logic
in hardware, basically sending periodically nullfunc frames and reporting
to the host if AP is lost.

Add support to mac80211 by adding a new flag IEEE80211_HW_CONNECTION_MONITOR
which prevents conn_mon_timer from triggering during idle periods.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
---
 include/net/mac80211.h |    1 +
 net/mac80211/mlme.c    |    3 +++
 2 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 80eb7cc..1d28fcc 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -975,6 +975,7 @@ enum ieee80211_hw_flags {
 	IEEE80211_HW_SUPPORTS_DYNAMIC_SMPS		= 1<<16,
 	IEEE80211_HW_SUPPORTS_UAPSD			= 1<<17,
 	IEEE80211_HW_REPORTS_TX_ACK_STATUS		= 1<<18,
+	IEEE80211_HW_CONNECTION_MONITOR			= 1<<19,
 };
 
 /**
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 4b9596f..3fa8e6a 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -850,6 +850,9 @@ void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,
 	if (is_multicast_ether_addr(hdr->addr1))
 		return;
 
+	if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR)
+		return;
+
 	mod_timer(&sdata->u.mgd.conn_mon_timer,
 		  round_jiffies_up(jiffies + IEEE80211_CONNECTION_IDLE_TIME));
 }