The HP Folio comes with a Broadcom BCM4313 802.11n Wifi module.    Getting this to work with WPA2 proved a struggle, and I had just-about given up and ordered a USB WIFI stick to get things working.  Luckily things started working with the BCM4313 card. In the end, I’m not sure “what did it” that fixed it, but it now works.   This documents my knowledge and outcome.

Broadcom Drivers

There are, it seems, 3 broadcom drivers.

1. The NDISWrapper (b43/b43legacy) does not work with the BCM4313 (but is apparently a work in progress)
2. The brcmsmac appears as wlan0 if that driver is used.
3. The wl driver appears as eth1, and this is the driver which eventually worked. I think this is also the default for an Ubuntu 12.04 install.

The Kernel

I initially started off with a 3.2.0-31-generic kernel, and tried installing the “wireless-compat” drivers.  This seemed to break things.  A number of reboots (yes, reboots, the initrd kept on getting rebuilt) later I am not using a 3.2.0.34-generic kernel, and suspect that this upgrade is part of the solution.

Configuration

I suspect part of the solution was reinstalling the WL driver after getting rid of the wifi-compat packages and instlaling the linux kernel.  To reinstall the wl driver

apt-get install --reinstall bcmwl-kernel-source

I tried using wifi-radar, wicd and even wpa_gui, but in the end wpa_supplicant is all that was required.

It was (I believe) necessary to manually bring the interface up initially.  I used the command

ifconfig eth1 up

Typing

iwlist eth1 scan

showed the available Access Points

In order to create the config I ran wpa_passphrase SSIDNAME Passphrase > /etc/ssid.conf

Bringing up the network is a matter of typing

wpa_supplicant -Dwext -ieth1 -c /etc/ssid.conf &