mac80211: Fix tx power setting

power_level in ieee80211_conf is being used for more than one
purpose. It being used as user configured power limit and the
final power limit given to the driver. By doing so, except very
first time, the tx power limit is taken from min(chan->max_power,
local->hw.conf.power_level) which is not what we want. This patch
defines a new memeber in ieee80211_conf which is meant only for
user configured power limit.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -546,6 +546,7 @@ enum ieee80211_conf_changed {
  * @listen_interval: listen interval in units of beacon interval
  * @flags: configuration flags defined above
  * @power_level: requested transmit power (in dBm)
+ * @user_power_level: User configured transmit power (in dBm)
  * @channel: the channel to tune to
  * @ht: the HT configuration for the device
  * @long_frame_max_tx_count: Maximum number of transmissions for a "long" frame
@@ -559,6 +560,7 @@ struct ieee80211_conf {
 	int beacon_int;
 	u32 flags;
 	int power_level;
+	int user_power_level;
 
 	u16 listen_interval;
 	bool radio_enabled;

net/mac80211/main.c

@@ -214,10 +214,10 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
 		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
 	}
 
-	if (!local->hw.conf.power_level)
+	if (!local->hw.conf.user_power_level)
 		power = chan->max_power;
 	else
-		power = min(chan->max_power, local->hw.conf.power_level);
+		power = min(chan->max_power, local->hw.conf.user_power_level);
 	if (local->hw.conf.power_level != power) {
 		changed |= IEEE80211_CONF_CHANGE_POWER;
 		local->hw.conf.power_level = power;

net/mac80211/wext.c

@@ -549,10 +549,9 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev,
 	else /* Automatic power level setting */
 		new_power_level = chan->max_power;
 
-	if (local->hw.conf.power_level != new_power_level) {
-		local->hw.conf.power_level = new_power_level;
+	local->hw.conf.user_power_level = new_power_level;
+	if (local->hw.conf.power_level != new_power_level)
 		reconf_flags |= IEEE80211_CONF_CHANGE_POWER;
-	}
 
 	if (local->hw.conf.radio_enabled != !(data->txpower.disabled)) {
 		local->hw.conf.radio_enabled = !(data->txpower.disabled);