From: Thomas Pedersen <thomas@cozybit.com>
Date: Thu, 26 Apr 2012 22:01:07 +0000 (-0700)
Subject: mac80211: don't transmit 40MHz frames to 20MHz peer
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c7d258288f2ad11eaa9656f6f9f48272a102fd1b;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

mac80211: don't transmit 40MHz frames to 20MHz peer

If a mesh peer indicates it is operating as 20MHz-only in its HT
operation IE, have the rate control algorithm respect this by disabling
the equivalent bit in the ieee80211_sta HT capabilities.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---

diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index f4124d7c556c..6209327840f7 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -302,6 +302,12 @@ static struct sta_info *mesh_peer_init(struct ieee80211_sub_if_data *sdata,
 	else
 		memset(&sta->sta.ht_cap, 0, sizeof(sta->sta.ht_cap));
 
+	if (elems->ht_operation)
+		if (!(elems->ht_operation->ht_param &
+		      IEEE80211_HT_PARAM_CHAN_WIDTH_ANY))
+			sta->sta.ht_cap.cap &=
+					    ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
+
 	rate_control_rate_init(sta);
 	spin_unlock_bh(&sta->lock);