diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h index 6334294f5f13..cefd28d5deee 100644 --- a/drivers/net/wireless/ath/ath5k/ath5k.h +++ b/drivers/net/wireless/ath/ath5k/ath5k.h @@ -992,6 +992,15 @@ struct ath5k_nfcal_hist s16 nfval[ATH5K_NF_CAL_HIST_MAX]; /* last few noise floors */ }; +/** + * struct avg_val - Helper structure for average calculation + * @avg: contains the actual average value + * @avg_weight: is used internally during calculation to prevent rounding errors + */ +struct ath5k_avg_val { + int avg; + int avg_weight; +}; /***************************************\ HARDWARE ABSTRACTION LAYER STRUCTURE @@ -1096,6 +1105,9 @@ struct ath5k_hw { struct ath5k_nfcal_hist ah_nfcal_hist; + /* average beacon RSSI in our BSS (used by ANI) */ + struct ath5k_avg_val ah_beacon_rssi_avg; + /* noise floor from last periodic calibration */ s32 ah_noise_floor; @@ -1305,4 +1317,27 @@ static inline u32 ath5k_hw_bitswap(u32 val, unsigned int bits) return retval; } +#define AVG_SAMPLES 8 +#define AVG_FACTOR 1000 + +/** + * ath5k_moving_average - Exponentially weighted moving average + * @avg: average structure + * @val: current value + * + * This implementation make use of a struct ath5k_avg_val to prevent rounding + * errors. + */ +static inline struct ath5k_avg_val +ath5k_moving_average(const struct ath5k_avg_val avg, const int val) +{ + struct ath5k_avg_val new; + new.avg_weight = avg.avg_weight ? + (((avg.avg_weight * ((AVG_SAMPLES) - 1)) + + (val * (AVG_FACTOR))) / (AVG_SAMPLES)) : + (val * (AVG_FACTOR)); + new.avg = new.avg_weight / (AVG_FACTOR); + return new; +} + #endif diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c index f60d84f9c55f..ba2fad23a7a5 100644 --- a/drivers/net/wireless/ath/ath5k/base.c +++ b/drivers/net/wireless/ath/ath5k/base.c @@ -1803,6 +1803,25 @@ ath5k_check_ibss_tsf(struct ath5k_softc *sc, struct sk_buff *skb, } } +static void +ath5k_update_beacon_rssi(struct ath5k_softc *sc, struct sk_buff *skb, int rssi) +{ + struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)skb->data; + struct ath5k_hw *ah = sc->ah; + struct ath_common *common = ath5k_hw_common(ah); + + /* only beacons from our BSSID */ + if (!ieee80211_is_beacon(mgmt->frame_control) || + memcmp(mgmt->bssid, common->curbssid, ETH_ALEN) != 0) + return; + + ah->ah_beacon_rssi_avg = ath5k_moving_average(ah->ah_beacon_rssi_avg, + rssi); + + /* in IBSS mode we should keep RSSI statistics per neighbour */ + /* le16_to_cpu(mgmt->u.beacon.capab_info) & WLAN_CAPABILITY_IBSS */ +} + /* * Compute padding position. skb must contains an IEEE 802.11 frame */ @@ -2022,6 +2041,8 @@ ath5k_tasklet_rx(unsigned long data) ath5k_debug_dump_skb(sc, skb, "RX ", 0); + ath5k_update_beacon_rssi(sc, skb, rs.rs_rssi); + /* check beacons in IBSS mode */ if (sc->opmode == NL80211_IFTYPE_ADHOC) ath5k_check_ibss_tsf(sc, skb, rxs);