diff options
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/recv.c | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index 2b2872baaa3..b3da81db453 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -236,10 +236,31 @@ static int ath_rx_prepare(struct sk_buff *skb, struct ath_desc *ds, rx_status->signal = rx_status->noise + ds->ds_rxstat.rs_rssi; rx_status->antenna = ds->ds_rxstat.rs_antenna; - /* at 45 you will be able to use MCS 15 reliably. A more elaborate - * scheme can be used here but it requires tables of SNR/throughput for - * each possible mode used. */ - rx_status->qual = ds->ds_rxstat.rs_rssi * 100 / 45; + /* + * Theory for reporting quality: + * + * At a hardware RSSI of 45 you will be able to use MCS 7 reliably. + * At a hardware RSSI of 45 you will be able to use MCS 15 reliably. + * At a hardware RSSI of 35 you should be able use 54 Mbps reliably. + * + * MCS 7 is the highets MCS index usable by a 1-stream device. + * MCS 15 is the highest MCS index usable by a 2-stream device. + * + * All ath9k devices are either 1-stream or 2-stream. + * + * How many bars you see is derived from the qual reporting. + * + * A more elaborate scheme can be used here but it requires tables + * of SNR/throughput for each possible mode used. For the MCS table + * you can refer to the wireless wiki: + * + * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n + * + */ + if (conf_is_ht(&hw->conf)) + rx_status->qual = ds->ds_rxstat.rs_rssi * 100 / 45; + else + rx_status->qual = ds->ds_rxstat.rs_rssi * 100 / 35; /* rssi can be more than 45 though, anything above that * should be considered at 100% */ |