• Johannes Berg's avatar
    mac80211: tell driver when idle · 5cff20e6
    Johannes Berg authored
    
    
    When we aren't doing anything in mac80211, we can turn off
    much of the hardware, depending on the driver/hw. Not doing
    anything, aka being idle, means:
    
     * no monitor interfaces
     * no AP/mesh/wds interfaces
     * any station interfaces are in DISABLED state
     * any IBSS interfaces aren't trying to be in a network
     * we aren't trying to scan
    
    By creating a new function that verifies these conditions and calling
    it at strategic points where the states of those conditions change,
    we can easily make mac80211 tell the driver when we are idle to save
    power.
    
    Additionally, this fixes a small quirk where a recalculated powersave
    state is passed to the driver even if the hardware is about to stopped
    completely.
    
    This patch intentionally doesn't touch radio_enabled because that is
    currently implemented to be a soft rfkill which is inappropriate here
    when we need to be able to wake up with low latency.
    
    One thing I'm not entirely sure about is this:
    
      phy0: device no longer idle - in use
      wlan0: direct probe to AP 00:11:24:91:07:4d try 1
      wlan0 direct probe responded
      wlan0: authenticate with AP 00:11:24:91:07:4d
      wlan0: authenticated
    > phy0: device now idle
    > phy0: device no longer idle - in use
      wlan0: associate with AP 00:11:24:91:07:4d
      wlan0: RX AssocResp from 00:11:24:91:07:4d (capab=0x401 status=0 aid=1)
      wlan0: associated
    
    Is it appropriate to go into idle state for a short time when we have
    just authenticated, but not associated yet? This happens only with the
    userspace SME, because we cannot really know how long it will wait
    before asking us to associate. Would going idle after a short timeout
    be more appropriate? We may need to revisit this, depending on what
    happens.
    Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    5cff20e6
mac80211.h 80.4 KB