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: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> --- For stable? I think we probably don't care enough. net/mac80211/main.c | 2 +- net/mac80211/wext.c | 43 ++++++++++++++++++++++++++++++++++--------- 2 files changed, 35 insertions(+), 10 deletions(-) --- wireless-testing.orig/net/mac80211/wext.c 2009-04-02 18:02:11.000000000 +0200 +++ wireless-testing/net/mac80211/wext.c 2009-04-07 10:58:11.000000000 +0200 @@ -417,6 +417,7 @@ static int ieee80211_ioctl_siwtxpower(st { 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(st 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; - - local->user_power_level = new_power_level; - if (local->hw.conf.power_level != new_power_level) - reconf_flags |= IEEE80211_CONF_CHANGE_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.radio_enabled != !(data->txpower.disabled)) { local->hw.conf.radio_enabled = !(data->txpower.disabled); @@ -442,7 +467,7 @@ static int ieee80211_ioctl_siwtxpower(st ieee80211_led_radio(local, local->hw.conf.radio_enabled); } - if (reconf_flags) + if (reconf || reconf_flags) ieee80211_hw_config(local, reconf_flags); return 0; --- wireless-testing.orig/net/mac80211/main.c 2009-04-07 10:44:24.000000000 +0200 +++ wireless-testing/net/mac80211/main.c 2009-04-07 10:44:33.000000000 +0200 @@ -258,7 +258,7 @@ int ieee80211_hw_config(struct ieee80211 (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) { -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html