Using the wl module with a bcm4352 card,  I enable wowlan via magic packet using the command:

iw phy phy0 wowlan enable magic-packet

verified with:

iw phy phy0 wowlan show

This works exactly once. I suspend the machine, and send it a magic packet via etherwake, and the system resumes.

However, after resuming, the bcm432 can no longer detect APs, and is disconnected from the wlan from which the magic packet is sent.

The following command returns nothing after resuming:

iw dwv wlan0 scan

If I rmmod wl to unload it, and modprobe wl to reload it, I'm back in business, but this means the box resumes with no network, making wowlan useless, since you need to be hands on to get the network back.