+static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
+{
+ struct sta_info *sta;
+ bool result = false;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+ if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
+ !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
+ !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
+ !sta->sta.ht_cap.ht_supported)
+ continue;
+ result = true;
+ break;
+ }
+ rcu_read_unlock();
+
+ return result;
+}
+
+static void
+iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta)
+{
+ struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+ bool tdls_ht;
+ u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
+ IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
+ IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
+ u16 opmode;
+
+ /* Nothing to do if the BSS connection uses HT */
+ if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
+ return;
+
+ tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
+ iee80211_tdls_have_ht_peers(sdata);
+
+ opmode = sdata->vif.bss_conf.ht_operation_mode;
+
+ if (tdls_ht)
+ opmode |= protection;
+ else
+ opmode &= ~protection;
+
+ if (opmode == sdata->vif.bss_conf.ht_operation_mode)
+ return;
+
+ sdata->vif.bss_conf.ht_operation_mode = opmode;
+ ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
+}
+