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Walton

Member

Registered: 2014-01-09

Posts: 23

[Solved] Function Keys for backlight

I'm trying to get the function keys to work for my Dell Inspiron 7000. I found this thread[1] that details creating a script for acpi commands. I'll summarize it here, with the slight variations I created to adjust for my path and my max brightness (1500).

/etc/acpi/actions/bl_down.sh

#!/bin/sh

bl_device=/sys/class/backlight/intel_backlight/brightness
echo $(($(cat $bl_device)-50))) | sudo tee $bl_device

/etc/acpi/actions/bl_up.sh

#!/bin/sh

bl_device=/sys/class/backlight/intel_backlight/brightness
echo $(($(cat $bl_device)+50))) | sudo tee $bl_device

/etc/acpi/events/bl_down

event=video/brightnessdown BRTDN 00000087 00000000
action=/etc/acpi/actions/bl_down.sh

/etc/acpi/events/bl_up

event=video/brightnessup BRTUP 00000086 00000000
action=/etc/acpi/actions/bl_up.sh

I then make the two sh scripts in the actions folder executable.

And just to confirm

$ acpi_listen
9DBB5994-A997-11000000d0 00000000
video/brightnessdown BRTDN 00000087 00000000
9DBB5994-A997-11000000d0 00000000
video/brightnessup BRTUP 00000086 00000000

I am a little confused about that 9D line. Sometimes it appears before the video/brightness part and sometimes after.

The interesting thing about all this is that the brightness down script works perfectly fine, but the up doesn't. So I tried even copying over the files and changing the only necessary parts. I am at a complete loss here at what might be happening.

[1] https://bbs.archlinux.org/viewtopic.php … 3#p1449243

Solution:
Edit params in grub

Last edited by Walton (2017-12-11 20:13:27)

lo1

Member

Registered: 2017-09-25

Posts: 584

Re: [Solved] Function Keys for backlight

/etc/acpi/events/bl_down
event=video/brightnessdown BRTDN 00000087 00000000
action=/etc/acpi/actions/bl_down.sh

/etc/acpi/events/bl_up
event=video/brightnessdown BRTUP 00000086 00000000
action=/etc/acpi/actions/bl_up.sh

...
Perhaps too many /video/brightnessdown?

Last edited by lo1 (2017-12-11 18:37:45)

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Walton

Member

Registered: 2014-01-09

Posts: 23

Re: [Solved] Function Keys for backlight

Sorry, that was a typo when pasting here. I fixed the OP

I will also add that the brightness up button does nothing. Even if I set it to run the bl_down script. So I think something is up with the key that it is associated with.

Last edited by Walton (2017-12-11 19:08:21)

lo1

Member

Registered: 2017-09-25

Posts: 584

Re: [Solved] Function Keys for backlight

Too easy to be true, I should have thought that.

My guess: https://wiki.archlinux.org/index.php/Ba … ne_options

If it doesn't work:

journalctl -f

and press the brightness keys, post the output here.

---

How To Ask Questions The Smart Way && Tacts Filters && K.I.S.S. &&
Rootless Root

Walton

Member

Registered: 2014-01-09

Posts: 23

Re: [Solved] Function Keys for backlight

The kernel params worked. I feel pretty dumb for missing those in the wiki. Thanks.

Though now when powering off I have some weird junk symbols. Doesn't seem to be affecting anything though.

Last edited by Walton (2017-12-11 20:20:03)