1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index f519d7396848..4a6a0bd01ff1 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -365,6 +365,40 @@ int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 
+void rt2x00mac_erp_ie_changed(struct ieee80211_hw *hw, u8 changes,
+                              int cts_protection, int preamble)
+{
+        struct rt2x00_dev *rt2x00dev = hw->priv;
+        int short_preamble;
+        int ack_timeout;
+        int ack_consume_time;
+        int difs;
+
+        /*
+         * We only support changing preamble mode.
+         */
+        if (!(changes & IEEE80211_ERP_CHANGE_PREAMBLE))
+                return;
+
+        short_preamble = !preamble;
+        preamble = !!(preamble) ? PREAMBLE : SHORT_PREAMBLE;
+
+        difs = (hw->conf.flags & IEEE80211_CONF_SHORT_SLOT_TIME) ?
+                SHORT_DIFS : DIFS;
+        ack_timeout = difs + PLCP + preamble + get_duration(ACK_SIZE, 10);
+
+        ack_consume_time = SIFS + PLCP + preamble + get_duration(ACK_SIZE, 10);
+
+        if (short_preamble)
+                __set_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
+        else
+                __clear_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
+
+        rt2x00dev->ops->lib->config_preamble(rt2x00dev, short_preamble,
+                                             ack_timeout, ack_consume_time);
+}
+EXPORT_SYMBOL_GPL(rt2x00mac_erp_ie_changed);
+
 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, int queue,
                       const struct ieee80211_tx_queue_params *params)
 {