systemd-backlight always fails at boot.

azaroma · 2015-06-24 01:53:32

Hi. I since i installed arch, the systemd-backlight@backlight:acpi_video0.service always fails at start up and then, i believe, systemd-backlight@backlight:radeon_bl0.service gets started.
In /sys/class/backlight/ theres only the radeon_bl0 folder. I would like to stop systemd from failing every boot by telling it that it should look for radeon_bl0 instead of the default
acpi_video0. This unit is static so trying to

systemctl enable systemd-backlight@radeon_bl0.service

does not work.
Output is:

==== AUTHENTICATION COMPLETE ===
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit's
   .wants/ or .requires/ directory.
2) A unit's purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).

Note: When i was using gnome 3 + gdm, brightness keys worked fine. They stopped working now that i'm using lightdm + openbox standalone. This might not be useful but just so you know that my goal, right now, is not trying to get brightness to work, i am concerned about this service failing all the time because it might be of impact on booting times; the screen goes black bafore the failure prints on screen.

Last edited by azaroma (2015-06-25 01:50:36)

mauritiusdadd · 2015-06-24 05:18:19

Are those names correct? They should be systemd-backlight@backlight:acpi_video0.service and systemd-backlight@backlight:radeon_bl0.service, is that a typo? However, do you have multiple video card? Have you tried to mask the failing unit as suggested in the wiki: https://wiki.archlinux.org/index.php/Ba … ht_service?

Last edited by mauritiusdadd (2015-06-24 05:18:31)

azaroma · 2015-06-25 02:16:59

Sorry, yes, it was a typo. I edited it. Well, i masked the systemd-backlight@.service service and, as expected, it is not loaded at boot. The screen still goes black for a few seconds where it should be loaded, though. The reason why i haven't masked it before is because the wiki says to do it when one atempt to load brightness settings by other means different to the backlight service, which, i'm not trying to do. Now my brigthness is at the highest level. This is not the behaviour that i was looking for, i want the systemd-backlight to stop creating an instance (systemd-backlight@backlight:acpi_video0.service) by telling it that it should look straight forward for systemd-backlight@backlight:radeon_bl0.service. My laptop http://support.hp.com/es-es/product/HP- … c03819815/

mauritiusdadd · 2015-06-25 06:42:58

azaroma wrote:

Sorry, yes, it was a typo. I edited it. Well, i masked the systemd-backlight@.service service and, as expected, it is not loaded at boot. The screen still goes black for a few seconds where it should be loaded, though. The reason why i haven't masked it before is because the wiki says to do it when one atempt to load brightness settings by other means different to the backlight service, which, i'm not trying to do.

That's not what I said, I said to try masking the unit that fails, which is systemd-backlight@backlight:acpi_video0.service, and not systemd-backlight@.service. It's suggested in the line just below the one where you stopped to read:

https://wiki.archlinux.org/index.php/Backlight#systemd-backlight_service wrote:

Some laptops have multiple video cards (e.g. Optimus) and the backlight restoration fails. Try masking an instance of the service, e.g. systemd-backlight@backlight\:acpi_video1 for acpi_video1.

However, first of all restore systemd-backlight@.service and then follow these instructions: https://wiki.archlinux.org/index.php/Ba … ne_options. If none of the methods described work, then try to mask the unit systemd-backlight@backlight:acpi_video0.service.

Arch Linux

#1 2015-06-24 01:53:32

systemd-backlight always fails at boot.

#2 2015-06-24 05:18:19

Re: systemd-backlight always fails at boot.

#3 2015-06-25 02:16:59

Re: systemd-backlight always fails at boot.

#4 2015-06-25 06:42:58

Re: systemd-backlight always fails at boot.

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