/etc/acpi/power.sh overrides user settings

Binary package hint: acpi-support

When operating a laptop on AC but within a moving vehicle, disk idleing ("laptop-mode") is needed even on AC. Not nessecarily to lett the disk spin down, but to leave the heads parked long enoght periods of time for shock protection.
(https://wiki.ubuntu.com/PowerManagement)

However, configuring /etc/laptop-mode/laptop-mode.conf appropriately gets overridden

1) /etc/acpi/power.sh calls laptop_mode with start/stop.

2) Setting less aggressive settings than hdparm -B1 (fastest headparking and spin down) on battery get overridden because power.sh will set hdparm -B1 _after_ calling laptop_mode start. (That even overrides any longer $HDPARM -S $SPINDOWN_TIME in the line before that one.)

"/sbin/laptop_mode auto" will check configured conditions itself. Laptop-mode won't be activated unless ENABLE_LAPTOP_MODE=true is also set in /etc/default/acpi-support, though. (/etc/init./laptop-mode checks that and therefore two places exist in ubuntu where disk-idleing (aka laptop-mode) needs to be anabled. The other is in laptop-mode.conf)

Flexible approach:

Package acpi-support:
Remove laptop_mode start/stop calls and hdparm stuff from power.sh
Remove ENABLE_LAPTOP_MODE setting from /etc/default/acpi-support. (And point to laptop-mode.conf for LM on battery, empty battery and AC.)

Package laptop-mode-tools:
Include scripts that call "/usr/bin/laptop_mode auto" in in /etc/acpi/ac.d, battery.d, resume.d and start.d. Then its the users choice to put scripts after or before the laptop-mode symlinks.
(Adapt the approach from the original laptop-mode-tools debian package to current ubuntu acpi-support)

(The current laptop-mode disk-idleing approach seems to be a left-over from before the ubuntu-laptop-mode package was droped for laptop-mode-tools.)