Having said that, it turned out it wasn't going to work out of the box on Jaunty either, but... it would not require any kernel compilations either. So I decided to give it a go.
Some things are documented on other blogs as well and I'll be copying/pasting a lot of content from there. However, I still ran into quite some problems that required digging further and further through the internet. Luckily I wasn't the only one, so I was able to find out how to get it to work properly. Please regard this post as summary of information gathered from all kinds of sources on the net. Unfortunately I can't remember all sources I used exactly, there were just too many before I found the ultimate solution, so I won't be giving any credits as I wouldn't like to ommit any (so therefor I give none - but I won't take credits either, it's mostly copy/paste completed with the things I recovered from the xterm history!!!).
How to get it to work:
The HDAPS system consist of two parts. The driver that enables reading the acceleration data and some sort of userspace software that does the actual parking of the harddrive heads, usually hdapsd.
The hdaps driver is part of the kernel but the driver maintainers actually recommend using the tp-smapi driver instead. So that’s what we’ll do.
Start by making sure you have the necessary tools installed
$ sudo apt-get install build-essential module-assistant
Luckily it’s in the package repository (universe)
$ sudo m-a a-i tp-smapi
this will fetch and install the tp-smapi-source package, unpack the source and then compile and install the kernel module. If you ever get the message that it is already compiled and you still want to recompile/reinstall it, throw in the -f (force) option here.
Try loading it:
$ sudo modprobe tp_smapi
$ sudo modprobe hdaps
The kernel log should show something like this (use dmesg):
[ 1546.780684] thinkpad_ec: thinkpad_ec 0.37 loaded.
[ 1546.784125] tp_smapi 0.37 loading...
[ 1546.784406] tp_smapi successfully loaded (smapi_port=0xb2).
[ 1571.445942] hdaps: LENOVO ThinkPad T61 detected, setting orientation 1
[ 1571.446111] hdaps: initial mode latch is 0x05
[ 1571.446265] hdaps: setting ec_rate=250, filter_order=2
[ 1571.446493] hdaps: device successfully initialized.
[ 1571.446607] input: ThinkPad HDAPS joystick emulation as /devices/virtual/input/input13
[ 1571.469284] input: ThinkPad HDAPS accelerometer data as /devices/virtual/input/input14
[ 1571.505138] hdaps: driver successfully loaded.
For some reason some configuration for udev is missing. Fix this by running
echo 'KERNEL=="event[0-9]*", ATTRS{phys}=="hdaps/input1",ATTRS{modalias}=="input:b0019v1014p5054e4801-*",SYMLINK+="input/hdaps/accelerometer-event"' | sudo tee /etc/udev/rules.d/51-hdaps.rules
Now for the userspace stuff. First let us test if APS is actually working.
$ sudo apt-get install hdaps-utils
After installation you can use hdaps-pivot or hdaps-gl to verify that the sensors are working
hdapsd in Jaunty is old. There is a PPA with newer versions.
Add the PPA to your repository list
$ cat | sudo tee /etc/apt/sources.list.d/hdapsd.list <<> deb http://ppa.launchpad.net/jonasped/ppa/ubuntu jaunty main
> deb-src http://ppa.launchpad.net/jonasped/ppa/ubuntu jaunty main
> EOF
And add the PPA key
$ sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 45EA2DEACE74152B61554DE4036A90F2BEFC6EB4
and then update the package list and install the package
$ sudo apt-get update
$ sudo apt-get install hdapsd
Remember to edit /etc/default/hdapsd to match your system. Most likely you will want to change the sensitivity settings. I found '15' to be too sensitive. At the moment I use '50', but you might want another setting...
Now, we're not there just yet. It will work with the above once, but after a reboot it will stop working again. Modprobe'ing will not work anymore either. It'll throw an error like:
thinpad_ec: Unknown parameter 'force_io'
when you try (check with dmesg). It took me 5 hours to find out why and how to resolve this.
It is because there an entry in /etc/modprobe.d/local.conf which explicitly loads the thinkpad_ec module with the option 'force_io=1'.
Open this file as root (sudo) for editing and comment the line which mentions the thinpad_ec module:
$ sudo gedit /etc/modprobe.d/local.confThe you can restart the HDASP demon with
$ sudo /etc/init.d/hdasp restart
Now you should be fine and it will work over reboots.
There are some pretty cool applets that will show you the status of the HDAPS system. I still use the Avant Window Manager and the latest version has an applet that shows it's status too. With these you can check if it actually works.
Also, the newer HDAPS system you now got implements a joystick device; now you can play Tuxrace by tilting your Thinkpad! Also available: an anti-theft alarm... more on these on the thinkwiki.