AR9285 RX sensitivity (was Re: Scanning with ath)

[Adrian Chadd]

Hi,

Right. Please enable hal/ath debugging:

options ATH_DEBUG
options AH_DEBUG
options ATH_DIAGAPI

Then enable diversity debugging:


sysctl dev.ath.0.hal.debug=0x00100000

The relevant code is in sys/dev/ath/ath_hal/ar9002/ar9285_diversity.c
. I "stole" the tx antenna switch hooks to implement the ar9285 RX
antenna diversity. It's a hack which I'll make go away at some point
(or if someone would like a mini-project, please step up and let me
know.)

sysctl dev.ath.0.txantenna thus:

0 = variable RX diversity
1 = RX prefer antenna A
2 = RX prefer antenna B

You could try setting it to 1 or 2 and doing some scans. "Variable"
allows the hardware to choose which antenna to use.

There's more complicated software-driven AR9285 diversity which I've
included the code for, but it's disabled at the moment due to a lack
of time to thoroughly debug issues (much like what you were seeing,
but when doing live traffic.) I'm happy to help out anyone who would
like to toy around with AR9285 software driven diversity, I have
plenty of documentation and notes which I can share.



Adrian