• Meenakshi Venkataraman's avatar
    iwlagn: Enable/disable PS poll based on RSSI and BT coex traffic state · 207ecc5e
    Meenakshi Venkataraman authored
    
    
    WiFi throughput drops drastically when BT is turned on, BT and WiFi
    are simultaneously transmitting/receiving traffic. This is particularly true
    when BT has higher priority over WiFi, and hence the device defers TX frames.
    The AP assumes that the channel is bad and reduces the data rate, implying
    longer airtime, which exacerbates the problem further, resulting ultimately
    in what is popularly called the "death-spiral" phenomenon. The use of PS-poll
    in such scenarios guarantees a low but consistent throughput.
    
    Since the death-spiral phenomenon is observed only when the RSSI is low, use
    PS-poll only when RSSI is low and disable when high, with a known hysterisis.
    
    This feature specifies the high and low thresholds and implements the
    callbacks registered with mac80211, which will be called when threshold events
    occur.
    
    iwlwifi: dynamic pspoll: optimize rssi monitor code
    Signed-off-by: default avatarMeenakshi Venkataraman <meenakshi.venkataraman@intel.com>
    Signed-off-by: default avatarWey-Yi Guy <wey-yi.w.guy@intel.com>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    207ecc5e