Commit 47afbaf5 authored by Johannes Berg's avatar Johannes Berg Committed by John W. Linville
Browse files

mac80211: correct wext transmit power handler 

Wext makes no assumptions about the contents of
data->txpower.fixed and data->txpower.value when
data->txpower.disabled is set, so do not update
the user-requested power level while disabling.

Also, when wext configures a really _fixed_ power
output [1], we should reject it instead of limiting it
to the regulatory constraint. If the user wants to set
a _limit_ [2] then we should honour that.

[1] iwconfig wlan0 txpower 20dBm fixed
[2] iwconfig wlan0 txpower 10dBm

This fixes
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1942



Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 853da11b

net/mac80211/main.c

+1 −1
Original line number Diff line number Diff line
@@ -258,7 +258,7 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed) 
			(chan->max_power - local->power_constr_level) :

			chan->max_power;



	if (local->user_power_level)

	if (local->user_power_level >= 0)

		power = min(power, local->user_power_level);



	if (local->hw.conf.power_level != power) {

net/mac80211/wext.c

+33 −8
Original line number Diff line number Diff line
@@ -417,6 +417,7 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev, 
{

	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);

	struct ieee80211_channel* chan = local->hw.conf.channel;

	bool reconf = false;

	u32 reconf_flags = 0;

	int new_power_level;
@@ -427,14 +428,38 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev, 
	if (!chan)

		return -EINVAL;



	if (data->txpower.fixed)

		new_power_level = min(data->txpower.value, chan->max_power);

	else /* Automatic power level setting */

		new_power_level = chan->max_power;

	/* only change when not disabling */

	if (!data->txpower.disabled) {

		if (data->txpower.fixed) {

			if (data->txpower.value < 0)

				return -EINVAL;

			new_power_level = data->txpower.value;

			/*

			 * Debatable, but we cannot do a fixed power

			 * level above the regulatory constraint.

			 * Use "iwconfig wlan0 txpower 15dBm" instead.

			 */

			if (new_power_level > chan->max_power)

				return -EINVAL;

		} else {

			/*

			 * Automatic power level setting, max being the value

			 * passed in from userland.

			 */

			if (data->txpower.value < 0)

				new_power_level = -1;

			else

				new_power_level = data->txpower.value;

		}



		reconf = true;



		/*

		 * ieee80211_hw_config() will limit to the channel's

		 * max power and possibly power constraint from AP.

		 */

		local->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);
@@ -442,7 +467,7 @@ static int ieee80211_ioctl_siwtxpower(struct net_device *dev, 
		ieee80211_led_radio(local, local->hw.conf.radio_enabled);

	}



	if (reconf_flags)

	if (reconf || reconf_flags)

		ieee80211_hw_config(local, reconf_flags);



	return 0;

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