[RFC] libertas: change quality calculation

[Holger Schurig]

> > I also found that the average noise floor is -86 dBm, not
> > -96 dBm. So I changed this constant. Maybe this is wrong,
> > what values do your cards report?
>
> When possible, we should use a window-ed average of the cards
> reported noise from beacons or received frames instead of a
> constant, that's a further improvement though.

The changed value of MRVDRV_NF_DEFAULT_SCAN_VALUE is only used to 
magically conjure the missing noise value for scan results, see 
my other mail about this.

Okay, it's also used in the case of a failed GET_RSSI command :-)

> Well, when we had the (badly) averaged array values in there,
> the noise floor was available to the scan reporting.

Something might have been available for scan reporting, but if 
this "something" made sense is a different question. See my 
other mail :-)

> There are tables to map RSSI -> dBm for each part which should
> be in the firmware spec or seen in the driver code.

I didn't see such a table so far, where is it?