HDAPS - IBM Active Protection System Linux Driver
This is the Linux driver for monitoring the accelerometer known as IBM Active Protection System.
The driver only enables reading of the acceleration data. It does not perform automatic disk head parking. But there are already some other useful applications for HDAPS, using the /sys interface it provides.
- provides accelerometer values via sysfs
- provides a joystick type input device
Project Homepage / Availability
- Project Homepage
- The driver is included in the 2.6-mm series of kernels since August, 26th 2005.
- The driver is now in the mainline (2.6.14).
- The tp_smapi package contains some patches to this driver. These are necessary for some recent models, and recommended for all.
A driver is included in recent Linux kernels and is actively maintained, but it is very inferior to the driver in tp_smapi (which provides its own hdaps module).
How to install the driver
If you are using a version of the Linux kernel < 2.6.14, please upgrade. I struggled long and hard to get the driver working with an old version of the kernel, and it was a mess. I gave up, upgraded my kernel, and one recompile later, HDAPS was working.
For 2.6.18 kernel, T60 users have to edit hdaps_init() in drivers/hwmon/hdaps.c to include a HDAPS_DMI_MATCH_LENOVO("ThinkPad T60") line.
Install the tp_smapi module if you experience problems with hdaps always reading out constant values of (0,0) refer
As mentioned above, the hdaps kernel driver is only responsible for reading the accelerometer data and exporting it through the sysfs interface. In order to use this information to protect the disk, some additional steps are required.
Input device support
The hdaps driver in the lastest kernels (2.6.14 and later?) also exports a joystick type input device, which can be used by games.
Disk head parking
You will need the kernel patch and userspace daemon. The GUI monitoring is optional.
See How to protect the harddisk through APS for more information.
Kernel patch (apply using 'patch -p1 -l < hdaps_xx.patch')
- disk park patch an experimental patch for parking the disk (Linux 2.6.14 for 2.6.15 see below)
- disk park patch adapted for the t41p model kernel 2.6.14 (capability detection disabled, no libata support)
- disk park patch adapted for the t41p model kernel 2.6.15 (capability detection disabled, no libata support)
- sata/ide disk protection patch for 2.6.15
- Latest sata/ide disk protection patch for 2.6.16
- Latest sata/ide disk protection patch for use with the libata hotplug 18.104.22.168 patches - See How_to_hotswap_UltraBay_devices
- Latest sata/ide disk protection patch for use with the libata hotplug 22.214.171.124 patches - See How_to_hotswap_UltraBay_devices
- Untested patch for 126.96.36.199: see 
- Latest sata/ide disk protection patch for 188.8.131.52
- Latest sata/ide disk protection patch for 2.6.19-rc6
- Latest sata/ide disk protection patch for 2.6.20 (old design)
- Latest sata/ide disk protection patch for 2.6.20 and 2.6.21 (new design)
- Latest sata/ide disk protection patch for 184.108.40.206 and 2.6.23-rc9 (new design)
- Recommended version
- Reduced power version - reduces timer interrupts, as measured by PowerTOP. This leads to lower power consumption on tickless kernels. Interrupt reduction requires the hdaps kernel module from tp_smapi 0.32 or newer, and a udev rule.
- Modified adaptive algorithm version - uses a different (and potentially better) algorithm for the adaptive sensivity threshold.
- khdapmonitor KDE System Tray Monitor
- gnome-hdaps-applet visual display of disk protection status in gnome panel
Security & safety
Visualisation of ThinkPad orientation
- hdaps-gl a little app animating a 3D-ThinkPad
- hdapsgl-applet a GNOME applet animating a 3D-ThinkPad
- wmadhps a WindowMaker DockApp animating a 3D-ThinkPad
- OpenGL gyroscope hack keeps your display levelled when tilting the ThinkPad
- Neverball is quite fun with HDAPS. (You'll need to have the HDAPS joystick device)
- Turn your ThinkPad into a Jedi Weapon (hey, it works for Mac laptops)
- smack.py - switch workspace by smacking your laptop, inspired by the SmackBook (uses EWMH)
- xmms-smack.py - move through your xmms playlist by smacking, based on the two smack scripts above.
- KnockBasedCommands - Execute commands by tapping your laptop.
- rotate.py - rotate desktop by turning your laptop
- HDAPS mailinglist and its archive
- #hdaps channel on irc.freenode.org
- hdaps projects overview of userspace programs using hdaps
- IBM ThinkPads hardware drive firmware site
- http://bugs.gentoo.org/show_bug.cgi?id=119845 Gentoo ebuild for hdaps driver and daemon including a initscript*
- http://bugs.gentoo.org/show_bug.cgi?id=137345 Gentoo ebuild for gkhdaps gkrell plugin
- http://bugs.gentoo.org/show_bug.cgi?id=137350 Gentoo ebuild for hdaps-gl application
- http://bugs.gentoo.org/show_bug.cgi?id=137351 Gentoo ebuild for gnome hdapsgl-applet
- http://bugs.gentoo.org/show_bug.cgi?id=137352 Gentoo ebuild for gnome tilt application
- http://bugs.gentoo.org/show_bug.cgi?id=137353 Gentoo ebuild for wmhdaps
- Why the ThinkPad accelerometer is only 2D - explanation by Lenovo