[SOLVED] Crazy Brightness after install of Current.

business_kid · 10-03-2014, 10:59 AM

One of the reasons for upgrading was to get rid of a brightness issue which was a result of a visit from a windows disk. Consoles and X would come up dark, and nothing seemed to be able to set them.

I removed everything (except virtualbox, wine, and a few other non essential packages) I have a full backup as of yesterday. Acpid definitely went. Installed Slackware-current, and my brightness issue is worse.

Code:

bash-4.3$ cd /sys
bash-4.3$ find -name 'brightness'
./devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness
./devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness
./devices/pci0000:00/0000:00:1c.1/0000:02:00.0/leds/ath9k-phy0/brightness

bash-4.3$ cat /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness
2261
bash-4.3$ cat /sys/devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness
47

---On bash-4.3$ cd /sys
bash-4.3$ find -name 'brightness'
./devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness
./devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness
./devices/pci0000:00/0000:00:1c.1/0000:02:00.0/leds/ath9k-phy0/brightness

bash-4.3$ cat /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness
2261
bash-4.3$ cat /sys/devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness
47

---On a Darkened console after visiting X---

dec@RoseViolet:~$ cat /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness
228
dec@RoseViolet:~$ cat /sys/devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness
100

This fixes it

Code:

echo 1500 > /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/brightness

Has anyone got a clue where that is coming from?
I used to have to adjust the consoles (once) and X (once). Now I have to adjust the consoles every time I do Alt_F7 followed by Ctrl_Alt_F2. I do use the old consoles from habit and bexause the fonts are bigger.

Do I have to wipe disks to shake this?

halvy · 10-05-2014, 06:38 PM

Are you thinking it's a virus (hence your thinking about wiping the disks?)

Maybe the obvious, hardware problem (degradations).. if not a kernel issue?

These new kernels lately.. have all kinds of stuff showing up on top.. I am sure you, like me, check them out.

business_kid · 10-06-2014, 03:54 AM

The brightness thing is a hangover from a visit from the original disk, with windows 8. It has uefi and is hopelessly complicated to dual boot.

Yes, I am thinking about wiping the / partition. After that (presuming it's not fixed), my home dir.

EDIT: I don't check out recent kernels. The emphasis always seems to be on writing drivers to control nutty devices like smart fridge magnets, unheard of protocols, and there is always one established safe piece of code that people want to throw out in favour of a theoretically better way (Which nobody has written yet).

business_kid · 10-11-2014, 03:20 AM

OK, I did the decent thing, because I got fed up looking at this. I HATE REINSTALLS. I reinstalled, after wiping the / drive completely. I am able to rob files back from a backup, so I am not as bad tempered about reinstalling as usual. Slackware-current.

Problem is still there. As I first tried X as root, with no users defined, that means
1. It's not something stored on the / drive.
2. It's not something stored in the home drive.
3. As I booted with a different lilo.conf, and a different kernel, it's hardly anything stored on /boot.
As there was an install CD (with no brightness issue) using the swap last, it's hardly from there. I did get it checked for bad block

I have no other hard drive space in use. Where the <expletive deleted> can it be coming from? I can only think the BIOS somewhere. But you don't have a brightness adjustment in the BIOS

business_kid · 10-11-2014, 03:26 AM

Grrr. I'm saying BIOS. I rebooted, and there lilo is as bright as you'rd ever want a screen to be. It's only when the Intel module loads during bootup that the thing dims. Can anyone point me at how to fiddle that?

55020 · 10-16-2014, 04:28 PM

I've been tolerating a similar problem with my bedroom lappie, which I want permanently set to the lowest possible brightness. This is running kernel 3.16 and xfce4-power-manager-1.4.1; I guess it was xfce4-power-manager-1.4.0 that messed it up. Anyway, here I am today with a 24 hour migraine, so I wanted a fix (even a few seconds of full brightness is agony). Reducing the brightness with the keyboard when at the LILO prompt has fixed it, so the bios is definitely implicated.

business_kid · 10-17-2014, 08:14 AM

I'll try it. But my keyboard is borked, and the Fn key doesn't function properly. Nevertheless, I can power off and give it a go.

business_kid · 10-17-2014, 01:24 PM

Rebooted in your honour, Sir and tried that.

The brightness is perfect at startup. It's when the kernel module loads that things go dim.

business_kid · 10-22-2014, 03:37 AM

Further to this:

This brightness thing has now gone totally awol. I have 2 figures that can need fiddling

/sys/class/backlight/acpi_video0/brightness - should be 100, usually is, but some things change it going dim.

/sys/class/backlight/intel_backlight/brightness - should be around 1400; Max is 4882, and this varies every change of screen, going ultra dim (238) or ultra bright(4882) randomly. Now I try to set 1400, and it sets 4882 :-O?

I seriously need to get this right at whatever cost. Is my video system dying, or is there firmware I can download to it or something? HD4000

business_kid · 10-23-2014, 08:32 AM

Ok. Some improvement.

1. Google informs me that this is a regular issue after a windows 8.1 update, or update attempt in my case.

2. I got onto Intel's site and tried their driver release. This is 2.99.911 which is a rew revisions back from 2.99.914.
That lists dependencies, libva, libva-intel, libdrm, xorg-server, Mesa, cairo, and a few others. Only cairo was up to date and my "install-everything" of slackware-current as of 30-9-2014 had no libva, or libva-intel.

So I spent a few hours yesterday bumping the revisions and upgrading support stuff and downgrading the intel driver. Tjhis fixed it to the extent that I can set the values with xbacklight and they hold if I flick to a console. That is something.

It even holds over a suspend. I have 2 scripts
1. bright which sets the values in /sys/class/backlight
2. brightness, usable by anyone, which reads them.

I am calling this solved, because it is better. It still comes up jammy side down from a reboot, but I can deal with that in rc.local