• Sergey Ryazanov's avatar
    ath9k: add calibration timeout for AR9002 · d8d20845
    Sergey Ryazanov authored
    ADC & I/Q calibrations could take infinite time to comple, since they
    depend on received frames. In particular the I/Q mismatch calibration
    requires receiving of OFDM frames for completion. But in the 2.4GHz
    band, a station could receive only CCK frames for a very long time.
    
    And while we wait for the completion of one of the mentioned
    calibrations, the NF calibration is blocked. Moreover, in some
    environments, I/Q calibration is unable to complete until a correct
    noise calibration will be performed due to AGC behaviour.
    
    In order to avoid delaying NF calibration on forever, limit the maximum
    duration of ADCs & I/Q calibrations. If the calibration is not completed
    within the maximum time, it will be interrupted and a next calibration
    will be performed. The code that selects the next calibration has been
    reworked to the loop so incompleted calibration will be respinned later.
    
    А maximum calibration time of 30 seconds was selected to give the
    calibration enough time to complete and to not interfere with the long
    (NF) calibration.
    
    Run tested with AR9220.
    Signed-off-by: default avatarSergey Ryazanov <ryazanov.s.a@gmail.com>
    Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
    Link: https://lore.kernel.org/r/20200424004923.17129-7-ryazanov.s.a@gmail.com
    d8d20845
hw.h 35.3 KB