Re: [PATCH 5/5] ath9k: Fix TX IQ calibration for SoC chips

[Wojciech Dubowik <Wojciech.Dubowik@neratec.com>]

On 01/16/2014 10:36 PM, Sujith Manoharan wrote:
> Wojciech Dubowik wrote:
>> I guess I won't be able to reproduce bad scan results with wireless
>> testing since I have
>> changed scan reporting to pure rssi in my openwrt compat.
>> In normal case you get a sum of rssi and noise floor and it will be
>> correct i.e. when
>> NF is shifted by 14db so will be rssi.
>> So it's just my use case.
>>
>> Anyway I have just solved the issue by applying calibrated noise floor
>> values from eeprom
>> instead of nominal in nf_get functions and nf histogram. Now the rssi
>> seems stable in my test
>> environment. I have just started testing but it looks promising.
> I don't see how that would fix the issue. The race still remains since
> there is a window between NF cal init and completion. The results
> of the calibration depends on the environment and using default values
> from the eeprom will not fix this, I think.
>
> Sujith
I agree it's more of a workaround because there can be situations
where measured value is far from calibrated. In my setup it
helps but I haven't yet tested what happens in the noisy environment.

Do you know a better way to fix this? I am not so deep into calibration
tasks but I have a working setup so I could spend more time on that.

Wojtek