[rt2x00-users] [PATCH RFC] rt2800: disable powersaving as default

[Johannes Stezenbach]

On Sun, Jan 30, 2011 at 07:50:37PM +0100, Johannes Stezenbach wrote:
> On Sun, Jan 30, 2011 at 05:16:09PM +0100, Ivo Van Doorn wrote:
> > As far as I understand, mac80211 will check if the beacon has been
> > received, and if
> > there are buffered frames (See ieee80211_rx_mgmt_beacon). If that is
> > the case the
> > powersaving is disabled. This code will only trigger if the
> > IEEE80211_HW_PS_NULLFUNC_STACK
> > is enabled (which is the case for rt2x00).
> > 
> > So only thing that will be needed is to check if PS is still enabled
> > after the ieee80211_rx function,
> > and bring the device back to sleep right?
> 
> That's my understanding, too.

However, I cannot find anywhere in mac80211 code where it would
check the bit in the TIM of a DTIM which indicates pending
broadcast/multicast traffic to be sent after the DTIM beacon.
I seems some drivers like carl9170 check this by itself.

(The bit to check is the lowest bit of struct ieee80211_tim_ie.bitmap_ctrl.)

Does this need to be fixed in mac80211 or is it expected that
the hw/fw checks this by itself and stays awake automatically
to receive the bc/mc traffic?


Johannes