mac80211: Fix quality reporting for wireless stats

Since "mac80211/cfg80211: move iwrange handler to cfg80211", the
results for link quality from "iwlist scan" and "iwconfig" commands
have been very different. The results are now consistent.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Reported- and tested-by: Larry Finger <larry.finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 39 insertions, 19 deletions

diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index f6924fc065d3..935c63ed3dfa 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -886,21 +886,6 @@ static int ieee80211_ioctl_siwauth(struct net_device *dev,
         return ret;
 }
 
-static u8 ieee80211_get_wstats_flags(struct ieee80211_local *local)
-{
-        u8 wstats_flags = 0;
-
-        wstats_flags |= local->hw.flags & (IEEE80211_HW_SIGNAL_UNSPEC |
-                                           IEEE80211_HW_SIGNAL_DBM) ?
-                                IW_QUAL_QUAL_UPDATED : IW_QUAL_QUAL_INVALID;
-        wstats_flags |= local->hw.flags & IEEE80211_HW_NOISE_DBM ?
-                                IW_QUAL_NOISE_UPDATED : IW_QUAL_NOISE_INVALID;
-        if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
-                wstats_flags |= IW_QUAL_DBM;
-
-        return wstats_flags;
-}
-
 /* Get wireless statistics.  Called by /proc/net/wireless and by SIOCGIWSTATS */
 static struct iw_statistics *ieee80211_get_wireless_stats(struct net_device *dev)
 {
@@ -922,10 +907,45 @@ static struct iw_statistics *ieee80211_get_wireless_stats(struct net_device *dev
                 wstats->qual.noise = 0;
                 wstats->qual.updated = IW_QUAL_ALL_INVALID;
         } else {
-                wstats->qual.level = sta->last_signal;
-                wstats->qual.qual = sta->last_qual;
-                wstats->qual.noise = sta->last_noise;
-                wstats->qual.updated = ieee80211_get_wstats_flags(local);
+                wstats->qual.updated = 0;
+                /*
+                 * mirror what cfg80211 does for iwrange/scan results,
+                 * otherwise userspace gets confused.
+                 */
+                if (local->hw.flags & (IEEE80211_HW_SIGNAL_UNSPEC |
+                                       IEEE80211_HW_SIGNAL_DBM)) {
+                        wstats->qual.updated |= IW_QUAL_LEVEL_UPDATED;
+                        wstats->qual.updated |= IW_QUAL_QUAL_UPDATED;
+                } else {
+                        wstats->qual.updated |= IW_QUAL_LEVEL_INVALID;
+                        wstats->qual.updated |= IW_QUAL_QUAL_INVALID;
+                }
+
+                if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) {
+                        wstats->qual.level = sta->last_signal;
+                        wstats->qual.qual = sta->last_signal;
+                } else if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
+                        int sig = sta->last_signal;
+
+                        wstats->qual.updated |= IW_QUAL_DBM;
+                        wstats->qual.level = sig;
+                        if (sig < -110)
+                                sig = -110;
+                        else if (sig > -40)
+                                sig = -40;
+                        wstats->qual.qual = sig + 110;
+                }
+
+                if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
+                        /*
+                         * This assumes that if driver reports noise, it also
+                         * reports signal in dBm.
+                         */
+                        wstats->qual.noise = sta->last_noise;
+                        wstats->qual.updated |= IW_QUAL_NOISE_UPDATED;
+                } else {
+                        wstats->qual.updated |= IW_QUAL_NOISE_INVALID;
+                }
         }
 
         rcu_read_unlock();