nl80211: Add frequency configuration (including HT40)

This patch adds new NL80211_CMD_SET_WIPHY attributes
NL80211_ATTR_WIPHY_FREQ and NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET to allow
userspace to set the operating channel (e.g., hostapd for AP mode).

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 41 insertions, 4 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 16423f9..7a7a6c1 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1095,6 +1095,18 @@ static int ieee80211_set_txq_params(struct wiphy *wiphy,
 	return 0;
 }
 
+static int ieee80211_set_channel(struct wiphy *wiphy,
+				 struct ieee80211_channel *chan,
+				 enum nl80211_sec_chan_offset sec_chan_offset)
+{
+	struct ieee80211_local *local = wiphy_priv(wiphy);
+
+	local->oper_channel = chan;
+	local->oper_sec_chan_offset = sec_chan_offset;
+
+	return ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+}
+
 struct cfg80211_ops mac80211_config_ops = {
 	.add_virtual_intf = ieee80211_add_iface,
 	.del_virtual_intf = ieee80211_del_iface,
@@ -1122,4 +1134,5 @@ struct cfg80211_ops mac80211_config_ops = {
 #endif
 	.change_bss = ieee80211_change_bss,
 	.set_txq_params = ieee80211_set_txq_params,
+	.set_channel = ieee80211_set_channel,
 };
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 155a2041..527205f 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -626,6 +626,7 @@ struct ieee80211_local {
 	struct delayed_work scan_work;
 	struct ieee80211_sub_if_data *scan_sdata;
 	struct ieee80211_channel *oper_channel, *scan_channel;
+	enum nl80211_sec_chan_offset oper_sec_chan_offset;
 	u8 scan_ssid[IEEE80211_MAX_SSID_LEN];
 	size_t scan_ssid_len;
 	struct list_head bss_list;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index cec9b6d..29c3ecf 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -195,20 +195,42 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
 	struct ieee80211_channel *chan;
 	int ret = 0;
 	int power;
+	enum nl80211_sec_chan_offset sec_chan_offset;
 
 	might_sleep();
 
-	if (local->sw_scanning)
+	if (local->sw_scanning) {
 		chan = local->scan_channel;
-	else
+		sec_chan_offset = NL80211_SEC_CHAN_NO_HT;
+	} else {
 		chan = local->oper_channel;
+		sec_chan_offset = local->oper_sec_chan_offset;
+	}
 
-	if (chan != local->hw.conf.channel) {
+	if (chan != local->hw.conf.channel ||
+	    sec_chan_offset != local->hw.conf.ht.sec_chan_offset) {
 		local->hw.conf.channel = chan;
+		switch (sec_chan_offset) {
+		case NL80211_SEC_CHAN_NO_HT:
+			local->hw.conf.ht.enabled = false;
+			local->hw.conf.ht.sec_chan_offset = 0;
+			break;
+		case NL80211_SEC_CHAN_DISABLED:
+			local->hw.conf.ht.enabled = true;
+			local->hw.conf.ht.sec_chan_offset = 0;
+			break;
+		case NL80211_SEC_CHAN_BELOW:
+			local->hw.conf.ht.enabled = true;
+			local->hw.conf.ht.sec_chan_offset = -1;
+			break;
+		case NL80211_SEC_CHAN_ABOVE:
+			local->hw.conf.ht.enabled = true;
+			local->hw.conf.ht.sec_chan_offset = 1;
+			break;
+		}
 		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
 	}
 
-
 	if (!local->hw.conf.power_level)
 		power = chan->max_power;
 	else
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 0f84131..505d68f 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -641,6 +641,7 @@ int ieee80211_set_freq(struct ieee80211_sub_if_data *sdata, int freqMHz)
 		    chan->flags & IEEE80211_CHAN_NO_IBSS)
 			return ret;
 		local->oper_channel = chan;
+		local->oper_sec_chan_offset = NL80211_SEC_CHAN_NO_HT;
 
 		if (local->sw_scanning || local->hw_scanning)
 			ret = 0;