#1 2018-02-02 06:43:35

microcord

Member

Registered: 2017-06-21

Posts: 31

[SOLVED] brightness control (yet again, sorry)

Hello, permanent NooB writing. Back in July, I easily installed BL, but unfortunately that computer died in December. I replaced it with a new Thinkpad E470: its low price was pleasant in itself but also suggested to me that it wouldn't have any troublesomely novel circuitry. I now think that this was optimistic. But one headache at a time; first off, the brightness controls.

Brightness seems to be at full blast. It should be adjustable via the F5 and F6 keys. It is not. This page (stackexchange.com) suggests using xev to see if keys do anything at all. The result: although F1, F2 and F3 do; F4 to F12 do not.

This page (stackexchange.com) suggests (among other solutions):

xbacklight -30% # decreases brightness by 30 percent

But xbacklight (after it's downloaded and installed) reports "No outputs have backlight property".

This is far from the first time that somebody's asked here about this problem. Questioners have been asked to report what the computer says about its video card. Here goes:

lspci | grep VGA

brings "00:02.0 VGA compatible controller: Intel Corporation Device 1916 (rev 07)"

lspci -knn | grep -iA2 vga

brings:

00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:1916] (rev 07)
Subsystem: Lenovo Device [17aa:505b]
00:14.0 USB controller [0c03]: Intel Corporation Device [8086:9d2f] (rev 21)

In this message in the BL forum, damo suggests using xrandr:

For example (use the connected display name for your system)

xrandr --output eDP-1-1 --brightness 1.1

However, I am An Idiot, and therefore I know neither the "connected display name" for my system nor where to put it within "xrandr --output eDP-1-1 --brightness 1.1".

Also, although I see miscellaneous other advice for the same problem, I don't know how much of it is likely to apply to my own (I'd thought humdrum) computer. In particular, I'm reluctant to explore backports (as recommended in this thread) unless/until somebody who understands this stuff says that doing so is likely to help and unlikely to harm.

Help, my brain hurts!

Last edited by microcord (2018-02-02 07:59:05)

brontosaurusrex

Middle Office

Registered: 2015-09-29

Posts: 2,755

Re: [SOLVED] brightness control (yet again, sorry)

You should figure out why the keyboard control is not working, as a temporary workaround this script is tested on two machines
https://raw.githubusercontent.com/bront … Brightness

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My website full of interesting stuff.

Head_on_a_Stick

Member

From: London

Registered: 2015-09-29

Posts: 9,093

Website

Re: [SOLVED] brightness control (yet again, sorry)

00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:1916] (rev 07)
Subsystem: Lenovo Device [17aa:505b]
00:14.0 USB controller [0c03]: Intel Corporation Device [8086:9d2f] (rev 21)

You have no video drivers loaded (because the hardware is too new).

Either follow https://forums.bunsenlabs.org/viewtopic.php?id=1185 to upgrade the graphics stack or try our new helium-dev development system:

https://forums.bunsenlabs.org/viewtopic.php?id=3800

This is based on Debian stretch and will offer much better hardware support OOTB.

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Para todos todo, para nosotros nada

microcord

Member

Registered: 2017-06-21

Posts: 31

Re: [SOLVED] brightness control (yet again, sorry)

You should figure out why the keyboard control is not working, as a temporary workaround this script is tested on two machines
https://raw.githubusercontent.com/bront … Brightness

Thank you, but unfortunately this doesn't work. It doesn't change the brightness; all it does is (twice) report:

xrandr: Failed to get size of gamma for output default

(This is also the first thing that xrandr says when run with no switches, etc.)

Incidentally (or relevantly?), while I was installing BL yesterday I was told that rtl_nic/rtl8168g-3.fw was missing. Not knowing what this meant or what I should do about it, I just ignored it; no further problems were apparent. Booting the system brings "mmc0 Unknown controller version (3) / You may experience problems"; but I believe that this refers to the slot for SD cards (which I've come to expect won't work on any machine; I use an adapter instead).

Oh -- there's also a message from Head_on_a_Stick. I'll try out their new suggestion.

brontosaurusrex

Middle Office

Registered: 2015-09-29

Posts: 2,755

Re: [SOLVED] brightness control (yet again, sorry)

I keep forgeting bunsen is still Jessie...

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My website full of interesting stuff.

microcord

Member

Registered: 2017-06-21

Posts: 31

Re: [SOLVED] brightness control (yet again, sorry)

Either follow https://forums.bunsenlabs.org/viewtopic.php?id=1185 to upgrade the graphics stack

Done! Very easy to follow (even for an idiot), and it works. (No need for xbacklight or xrandr; I simply press the F5 and F6 keys, as Messrs Lenovo intended.)

or try our new helium-dev development system:

https://forums.bunsenlabs.org/viewtopic.php?id=3800

This is based on Debian stretch and will offer much better hardware support OOTB.

That looked a bit daunting by contrast. I'll keep it in mind, however.

Many thanks, and may you always have a good supply of heads for your stick!

microcord

Member

Registered: 2017-06-21

Posts: 31

Re: [SOLVED] brightness control (yet again, sorry)

I keep forgeting bunsen is still Jessie...

Well, er, I was thinking briefly about asking a related question, but I paused to take a little stroll around "Helium Release Date". I noticed that this falls within "Topics Going Nowhere", and I decided that it would be prudent to hold my tongue....