# Hpfall

hpfall is a simple daemon providing HDD shock protection for HP laptops supporting the feature officially called "HP Mobile Data Protection System 3D" or "HP 3D DriveGuard".

## Installation

You can install hpfall-gitAUR, which is available in the AUR.

## Configuration

You need to set your HDD in `/etc/conf.d/hpfall`.

If your HDD is `/dev/sda`, your config file should look like this:

    /etc/conf.d/hpfall

    #
    # Parameters to be passed to hpfall
    #
    DEVICE=/dev/sda

Start and enable `hpfall.service`

## Testing

After reboot with new kernel, check if hp_accel driver was initialised correctly:

    # dmesg | grep hp_accel

### Testing Shock protection

Warning: Be careful while performing this test and keep your laptop above something soft. Simulating free fall over the desk is bad idea.

Find your HDD's unload_heads file:

    # find /sys -name unload_heads

Go to it's directory and run:

    # watch --difference=permanent cat unload_heads

Lift you laptop into free space and simulate free fall while holding it firmly with your hands. About 10 cm should be enough. If the disk protection works then you should hear your HDD making "click" sound, see one of your laptop's LEDs flashing and the watch value's background should permanently turn black.

Category:

- HP