diff options
| author | Simon Wunderlich <simon.wunderlich@s2003.tu-chemnitz.de> | 2013-07-08 16:55:55 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2013-07-16 09:58:08 +0300 |
| commit | 0430c883470d0c9a23661ea9f02c56b1d91cf93c (patch) | |
| tree | 719ac23c82a3ed725ad3e0155cf223720be02e75 | |
| parent | 74608aca4d82e2855b1a6a2cd60331d1a98f2d6a (diff) | |
| download | linux-0430c883470d0c9a23661ea9f02c56b1d91cf93c.tar.bz2 | |
cfg80211/mac80211: use reduced txpower for 5 and 10 MHz
Some regulations (like germany, but also FCC) express their transmission
power limit in dBm/MHz or mW/MHz. To cope with that and be on the safe
side, reduce the maximum power to half (10 MHz) or quarter (5 MHz)
when operating on these reduced bandwidth channels.
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
| -rw-r--r-- | include/net/cfg80211.h | 27 | ||||
| -rw-r--r-- | net/mac80211/iface.c | 2 | ||||
| -rw-r--r-- | net/mac80211/main.c | 2 | ||||
| -rw-r--r-- | net/mac80211/mlme.c | 3 |
4 files changed, 31 insertions, 3 deletions
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 88f15631701a..aeaf6dff6e05 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -461,6 +461,33 @@ ieee80211_chandef_rate_flags(struct cfg80211_chan_def *chandef) } /** + * ieee80211_chandef_max_power - maximum transmission power for the chandef + * + * In some regulations, the transmit power may depend on the configured channel + * bandwidth which may be defined as dBm/MHz. This function returns the actual + * max_power for non-standard (20 MHz) channels. + * + * @chandef: channel definition for the channel + * + * Returns: maximum allowed transmission power in dBm for the chandef + */ +static inline int +ieee80211_chandef_max_power(struct cfg80211_chan_def *chandef) +{ + switch (chandef->width) { + case NL80211_CHAN_WIDTH_5: + return min(chandef->chan->max_reg_power - 6, + chandef->chan->max_power); + case NL80211_CHAN_WIDTH_10: + return min(chandef->chan->max_reg_power - 3, + chandef->chan->max_power); + default: + break; + } + return chandef->chan->max_power; +} + +/** * enum survey_info_flags - survey information flags * * @SURVEY_INFO_NOISE_DBM: noise (in dBm) was filled in diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index cc117591f678..4c41c11958c8 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -54,7 +54,7 @@ bool __ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata) return false; } - power = chanctx_conf->def.chan->max_power; + power = ieee80211_chandef_max_power(&chanctx_conf->def); rcu_read_unlock(); if (sdata->user_power_level != IEEE80211_UNSET_POWER_LEVEL) diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 091088ac7890..6da98c77496b 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -151,7 +151,7 @@ static u32 ieee80211_hw_conf_chan(struct ieee80211_local *local) changed |= IEEE80211_CONF_CHANGE_SMPS; } - power = chandef.chan->max_power; + power = ieee80211_chandef_max_power(&chandef); rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) { diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index f7552c2b74eb..211246b46819 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -747,7 +747,8 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata) *pos++ = WLAN_EID_PWR_CAPABILITY; *pos++ = 2; *pos++ = 0; /* min tx power */ - *pos++ = chan->max_power; /* max tx power */ + /* max tx power */ + *pos++ = ieee80211_chandef_max_power(&chanctx_conf->def); /* 2. supported channels */ /* TODO: get this in reg domain format */ |