On Thu, Feb 15, 2018 at 07:51:28AM +0200, Kalle Valo wrote: > James Cameron <quozl@xxxxxxxxxx> writes: > > > On Wed, Feb 14, 2018 at 04:26:42PM +0000, Jean Pierre TOSONI wrote: > >> ath9k returns a wrong RSSI value for frames received in a 30ms time > >> window after a channel change. The correct value is typically 10dB > >> below the returned value. > > > > How was your correct value determined? > > > >> This was found with a Atheros AR9300 Rev:3 chip (WLE350NX / JWX6083 > >> cards), during offchannel scans. > >> > >> Mark the signal value as invalid in this case. > > > > Why not adjust by 10dB? > > > > Speculating: in a typical card, RSSI is calculated by firmware from > > readings of ADCs attached to the receiver. Firmware may average > > several readings. Firmware may apply other offsets or calibrations, > > based on frequency and temperature. This sounds like a firmware > > problem. > > ath9k does not have firmware, only ath9k_htc has it. Heh. s/firmware/silicon implementation/g -- James Cameron http://quozl.netrek.org/
