From 67af9811539be83dbdc0739215d29af23c870405 Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach Date: Sun, 18 May 2014 10:15:24 +0300 Subject: cfg80211: allow RSSI compensation Channels in 2.4GHz band overlap, this means that if we send a probe request on channel 1 and then move to channel 2, we will hear the probe response on channel 2. In this case, the RSSI will be lower than if we had heard it on the channel on which it was sent (1 in this case). The firmware / low level driver can parse the channel in the DS IE or HT IE and compensate the RSSI so that it will still have a valid value even if we heard the frame on an adjacent channel. This can be done up to a certain offset. Add this offset as a configuration for the low level driver. A low level driver that can compensate the low RSSI in this case should assign the maximal offset for which the RSSI value is still valid. Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/wireless/scan.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'net/wireless/scan.c') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 0f5da18cc619..77c56eef0574 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -883,6 +883,7 @@ cfg80211_inform_bss_width(struct wiphy *wiphy, struct cfg80211_bss_ies *ies; struct ieee80211_channel *channel; struct cfg80211_internal_bss tmp = {}, *res; + bool signal_valid; if (WARN_ON(!wiphy)) return NULL; @@ -919,8 +920,9 @@ cfg80211_inform_bss_width(struct wiphy *wiphy, rcu_assign_pointer(tmp.pub.beacon_ies, ies); rcu_assign_pointer(tmp.pub.ies, ies); - res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, - rx_channel == channel); + signal_valid = abs(rx_channel->center_freq - channel->center_freq) <= + wiphy->max_adj_channel_rssi_comp; + res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); if (!res) return NULL; @@ -944,6 +946,7 @@ cfg80211_inform_bss_width_frame(struct wiphy *wiphy, struct cfg80211_internal_bss tmp = {}, *res; struct cfg80211_bss_ies *ies; struct ieee80211_channel *channel; + bool signal_valid; size_t ielen = len - offsetof(struct ieee80211_mgmt, u.probe_resp.variable); @@ -991,8 +994,9 @@ cfg80211_inform_bss_width_frame(struct wiphy *wiphy, tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); - res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, - rx_channel == channel); + signal_valid = abs(rx_channel->center_freq - channel->center_freq) <= + wiphy->max_adj_channel_rssi_comp; + res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); if (!res) return NULL; -- cgit v1.2.3