Test on the madwifi (r 2171) suspend/resume fails on the pxa270 board integrated with atheros miniPci card running linux 2.6.16.
An AP is created and performed the test "suspend/resume" using userspace power management. 
Test on "standby" mode works fine. All the running tasks are stopped and started. I could see the AP disappear and appear again.
echo 2 > /sys/powertimeout
echo "standby" > /sys/power/state
Whereas it fails with test on "mem" . All the tasks are stopped and started except the ath0 and the interface is not associated.
iwconfig shows Acces Point: Not-Associated
echo 2 > /sys/powertimeout
echo "mem" > /sys/power/state
Stopping tasks: ===========|
ath_suspend ..
Restarting tasks...handle_update for cpu 0 called
updating policy for CPU 0
eth0: link down
eth0: link up, 100Mbps, full-duplex, lpa 0x41E1
ath0 interface is not resumed anymore and the dmesg shows 
wifi0: unable to reset hardware: '' (HAL status 6492) (freq 2412 flags 0xa0)
Can anybody precise me why it functions well with "standby" and not with "mem" PM.