diff options
| author | Simon Wunderlich <simon.wunderlich@s2003.tu-chemnitz.de> | 2013-07-08 18:55:55 +0400 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2013-07-16 10:58:08 +0400 |
| commit | 0430c883470d0c9a23661ea9f02c56b1d91cf93c (patch) | |
| tree | 719ac23c82a3ed725ad3e0155cf223720be02e75 /include/net/cfg80211.h | |
| parent | 74608aca4d82e2855b1a6a2cd60331d1a98f2d6a (diff) | |
| download | linux-0430c883470d0c9a23661ea9f02c56b1d91cf93c.tar.xz | |
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>
Diffstat (limited to 'include/net/cfg80211.h')
| -rw-r--r-- | include/net/cfg80211.h | 27 |
1 files changed, 27 insertions, 0 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 |