Acer/Ivybridge vs Screen Brightness

[mykrob]

Will do, but may be a bit later tonight. Gotta finish up work, then band practice. Long day.

Thanks

[mykrob]

Can you try a few other options? After each option, please post back:
1. The kernel boot line:

cat /proc/cmdline

2. Your backlight interfaces:

for i in /sys/class/backlight/*; do echo $i; cat $i/brightness; cat $i/max_brightness; done

3. Your dmesg file:

pastebinit /var/log/dmesg

4. Whether the brightness function keys/brightness slider works.

The options to try are (some you've already tried, but please try again):
- GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=\"!Windows 2012\""
- GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force acpi_backlight=vendor"
- GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"

I'd like to have a closer look at the dmesg files and the backlight interfaces.

First one out of the gate worked

The first one I tried was GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"

That said, here is the other information you requested, maybe it will help you understand why it worked, so you can explain it to me

myk@myk-Aspire:~$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-3.8.0-23-generic.efi.signed root=UUID=3d62caab-2bac-40b9-891e-e79eb8afd3cb ro quiet splash acpi_osi=Linux acpi_backlight=vendor vt.handoff=7

myk@myk-Aspire:~$ for i in /sys/class/backlight/*; do echo $i; cat $i/brightness; cat $i/max_brightness; done
/sys/class/backlight/intel_backlight
96
976

myk@myk-Aspire:~$ pastebinit /var/log/dmesg
http://paste.ubuntu.com/5740645/

Brightness hotkeys and slider are working. Thank you so much.

[Toz]

Perfect. Glad to hear.

I noticed, after the fact, that you had mispelled backlight in your post #2. That was the first option and it worked. So you were close.

acpi_osi=Linux tells the kernel to inform the bios that it is Linux so that it loads a certain set of acpi tables specific to Linux. acpi_backlight=vendor tells acpi to not use built in brightness management (acpi_video0), but to let the bios handle the brightness (in your case, intel_backlight).

[mauricio288]

Could you both please help me?
I have the same laptop Model (except that my intel generation is the second one), and I have tried the GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor" but no luck. The other diference is that I use Kubuntu, I allready ask on their forums, but no luck
Please help

[Toz]

Could you both please help me?
I have the same laptop Model (except that my intel generation is the second one), and I have tried the GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor" but no luck. The other diference is that I use Kubuntu, I allready ask on their forums, but no luck
Please help

Can you confirm some information:
1. The version of kubuntu you are using.

2. Your current kernel boot parameter line:

cat /proc/cmdline

3. Your video card and driver:

lspci -k | grep -A3 VGA

4. Your backlight interfaces and their values:

for i in /sys/class/backlight/*; do echo $i; cat $i/brightness; cat $i/actual_brightness; cat $i/max_brightness; done

5. Your dmesg log file:

pastebinit /var/log/dmesg

...and post back the link that is generated.

6. Your Xorg log file:

pastebinit /var/log/Xorg.0.log

...and post back the link that is generated.

[mauricio288]

Can you confirm some information:
1. The version of kubuntu you are using.

2. Your current kernel boot parameter line:

cat /proc/cmdline

3. Your video card and driver:

lspci -k | grep -A3 VGA

4. Your backlight interfaces and their values:

for i in /sys/class/backlight/*; do echo $i; cat $i/brightness; cat $i/actual_brightness; cat $i/max_brightness; done

5. Your dmesg log file:

pastebinit /var/log/dmesg

...and post back the link that is generated.

6. Your Xorg log file:

pastebinit /var/log/Xorg.0.log

...and post back the link that is generated.

1. My version is Kubuntu 13.10 (same problem with 13.04) Kernel 3.11.0.12

2. cat /proc/cmdline

BOOT_IMAGE=/boot/vmlinuz-3.11.0-12-generic root=UUID=0b573e08-fee6-43ca-af4c-2a98a22f5952 ro quiet splash acpi_osi=Linux acpi_backlight=vendor vt.handoff=7

3. lspci -k | grep -A3 VGA

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
        Subsystem: Acer Incorporated [ALI] Device 072a
        Kernel driver in use: i915
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)

4. for i in /sys/class/backlight/*; do echo $i; cat $i/brightness; cat $i/actual_brightness; cat $i/max_brightness; done

/sys/class/backlight/intel_backlight
488
488
976

5. pastebinit /var/log/dmesg
http://paste.ubuntu.com/6274034/

6. pastebinit /var/log/Xorg.0.log
http://paste.ubuntu.com/6274043/

Tanks for the reply

[Toz]

Can you try this:

1. Create the file /usr/share/X11/xorg.conf.d/20-intel.conf:

sudo -i kate /usr/share/X11/xorg.conf.d/20-intel.conf

...enter your password when prompted.

2. Copy/paste the following content:

Section "Device"
        Identifier  "card0"
        Driver      "intel"
        Option      "Backlight"  "intel_backlight"
        BusID       "PCI:0:2:0"
EndSection

3. Save the file.

4. Log out and back in again to see if it works.

If it still doesn't work, try removing the extra kernel parameters you added and trying again.

[mauricio288]

Can you try this:

1. Create the file /usr/share/X11/xorg.conf.d/20-intel.conf:

sudo -i kate /usr/share/X11/xorg.conf.d/20-intel.conf

...enter your password when prompted.

2. Copy/paste the following content:

Section "Device"
        Identifier  "card0"
        Driver      "intel"
        Option      "Backlight"  "intel_backlight"
        BusID       "PCI:0:2:0"
EndSection

3. Save the file.

4. Log out and back in again to see if it works.

If it still doesn't work, try removing the extra kernel parameters you added and trying again.

It worked
it Worked!!!!

I had to remove the kernel parameters for this to work

Thanks for the help, that thing was driving me crazy, but now it's solved.

I'll post it to my blog to help others, I'm not the only one with this problem

Thanks again

[Toz]

Glad to hear. Out of curiosity, did you remove the kernel parameters or are you still using them?

[mauricio288]

Yep I remove the parameters.