[PATCH] bcm43xx: improved statistics

This patch improves the statistics returned from
bcm43xx_get_wireless_stats. The signal level comes from smoothing the
"rssi" value returned by the firmware after it is converted into a
dBm value by the driver. The quality value is a hack derived from the
smoothed level and an assumed RX_POWER_MAX of -10 dBM. The noise value
is still the one calculated from the clean-room formula. On my system,
this is roughly -65 dBm, which seems too high.

The revised version uses the ieee80211 spinlock to protect traversing
of the network list.

Signed-Off-By: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 28 insertions, 13 deletions

diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_wx.c b/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
index ebe2a8469a78..8ffd760dc830 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
@@ -47,6 +47,9 @@
 #define BCM43xx_WX_VERSION      18
 
 #define MAX_WX_STRING           80
+/* FIXME: the next line is a guess as to what the maximum value of RX power
+          (in dBm) might be */
+#define RX_POWER_MAX            -10
 
 
 static int bcm43xx_wx_get_name(struct net_device *net_dev,
@@ -228,14 +231,14 @@ static int bcm43xx_wx_get_rangeparams(struct net_device *net_dev,
 
         range->max_qual.qual = 100;
         /* TODO: Real max RSSI */
-        range->max_qual.level = 3;
-        range->max_qual.noise = 100;
-        range->max_qual.updated = 7;
+        range->max_qual.level = 0;
+        range->max_qual.noise = 0;
+        range->max_qual.updated = IW_QUAL_ALL_UPDATED;
 
-        range->avg_qual.qual = 70;
-        range->avg_qual.level = 2;
-        range->avg_qual.noise = 40;
-        range->avg_qual.updated = 7;
+        range->avg_qual.qual = 50;
+        range->avg_qual.level = 0;
+        range->avg_qual.noise = 0;
+        range->avg_qual.updated = IW_QUAL_ALL_UPDATED;
 
         range->min_rts = BCM43xx_MIN_RTS_THRESHOLD;
         range->max_rts = BCM43xx_MAX_RTS_THRESHOLD;
@@ -840,6 +843,9 @@ static struct iw_statistics *bcm43xx_get_wireless_stats(struct net_device *net_d
         struct bcm43xx_private *bcm = bcm43xx_priv(net_dev);
         struct ieee80211softmac_device *mac = ieee80211_priv(net_dev);
         struct iw_statistics *wstats;
+        struct ieee80211_network *network = NULL;
+        static int tmp_level = 0;
+        unsigned long flags;
 
         wstats = &bcm->stats.wstats;
         if (!mac->associated) {
@@ -857,16 +863,25 @@ static struct iw_statistics *bcm43xx_get_wireless_stats(struct net_device *net_d
                 wstats->qual.level = 0;
                 wstats->qual.noise = 0;
                 wstats->qual.updated = 7;
-                wstats->qual.updated |= IW_QUAL_NOISE_INVALID |
-                        IW_QUAL_QUAL_INVALID | IW_QUAL_LEVEL_INVALID;
+                wstats->qual.updated |= IW_QUAL_ALL_UPDATED;
                 return wstats;
         }
         /* fill in the real statistics when iface associated */
-        wstats->qual.qual = 100;     // TODO: get the real signal quality
-        wstats->qual.level = 3 - bcm->stats.link_quality;
+        spin_lock_irqsave(&mac->ieee->lock, flags);
+        list_for_each_entry(network, &mac->ieee->network_list, list) {
+                if (!memcmp(mac->associnfo.bssid, network->bssid, ETH_ALEN)) {
+                        if (!tmp_level)         /* get initial value */
+                                tmp_level = network->stats.rssi;
+                        else                    /* smooth results */
+                                tmp_level = (7 * tmp_level + network->stats.rssi)/8;
+                        break;
+                }
+        }
+        spin_unlock_irqrestore(&mac->ieee->lock, flags);
+        wstats->qual.level = tmp_level;
+        wstats->qual.qual = 100 + tmp_level - RX_POWER_MAX; // TODO: get the real signal quality
         wstats->qual.noise = bcm->stats.noise;
-        wstats->qual.updated = IW_QUAL_QUAL_UPDATED | IW_QUAL_LEVEL_UPDATED |
-                        IW_QUAL_NOISE_UPDATED;
+        wstats->qual.updated = IW_QUAL_ALL_UPDATED;
         wstats->discard.code = bcm->ieee->ieee_stats.rx_discards_undecryptable;
         wstats->discard.retries = bcm->ieee->ieee_stats.tx_retry_limit_exceeded;
         wstats->discard.nwid = bcm->ieee->ieee_stats.tx_discards_wrong_sa;