ath9k: differentiate quality reporting between legacy and HT configurations
We were not differentiating quality between legacy and HT
configurations. We change this to consider the differences.
New 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
This should fix this bug report:
http://bugzilla.kernel.org/show_bug.cgi?id=13537
Cc: Janath.Peiris@atheros.com
Cc: Matt.Smith@atheros.com
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
1 file changed