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 16423f94801b..7a7a6c176dc5 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 155a20410017..527205f8c1a1 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 cec9b6d3e1ce..29c3ecf7e914 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 0f841317c7e9..505d68f344ce 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;