Cannot control brightness settings on Vaio

tantramar · 05-11-2011, 04:39 PM

I just finished installing Slackware64 13.37 on my Sony Vaio PCG-7153L, and I'm having issues controlling the LCD brightness of the laptop. It still has the stock Slack kernel 2.6.37.6 SMP
The brightness controls worked on Fedora 12-14, as well as the Ubuntu 10.04 live disc.

I checked /proc/acpi/, but there's nothing in there to control brightness.

I reloaded the sony_laptop kernel module, and from dmesg I get:

Code:

sony-laptop: brightness ignored, must be controlled by ACPI video driver

From the Ubuntu bug (https://bugs.launchpad.net/ubuntu/+s...id/+bug/340513) and the Red Hat bug (https://bugzilla.redhat.com/show_bug.cgi?id=519105), it looks like they've already dealt with this problem. However, as I said earlier, my laptop worked fine with Fedora 12-14.

Any ideas? I know Slackware does minimal fiddling with the kernel, so I'm thinking this might be an upstream kernel bug...

PhoenixAndThor · 05-11-2011, 05:08 PM

Well, the error message could be referring to the actual video card driver. If you tell us what video card you have in your laptop, we may be able to help.

tantramar · 05-11-2011, 05:17 PM

Here's the videocard details:

Code:

00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series 
Chipset Integrated Graphics Controller (rev 07) (prog-if 00 [VGA controller])
        Subsystem: Sony Corporation Device 9045
        Flags: bus master, fast devsel, latency 0, IRQ 44
        Memory at d0000000 (64-bit, non-prefetchable) [size=4M]
        Memory at c0000000 (64-bit, prefetchable) [size=256M]
        I/O ports at e140 [size=8]
        Expansion ROM at <unassigned> [disabled]
        Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Capabilities: [d0] Power Management version 3
        Kernel driver in use: i915
        Kernel modules: i915

00:02.1 Display controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
        Subsystem: Sony Corporation Device 9045
        Flags: bus master, fast devsel, latency 0
        Memory at d0400000 (64-bit, non-prefetchable) [size=1M]
        Capabilities: [d0] Power Management version 3

allend · 05-11-2011, 07:13 PM

Post #180 from the Ubuntu bug report you linked says that patches have been accepted into the 2.6.39 mainline kernel.
Try the later kernel.

bosth · 05-11-2011, 07:22 PM

Try adding this to your kernel parameters in lilo.conf:

Quote:

acpi_osi=Linux

Software control over brightness probably won't come back, but fn keys might work.

tantramar · 05-12-2011, 11:35 AM

Quote:

Originally Posted by bosth

Try adding this to your kernel parameters in lilo.conf:

Software control over brightness probably won't come back, but fn keys might work.

Quote:

Originally Posted by allend

Post #180 from the Ubuntu bug report you linked says that patches have been accepted into the 2.6.39 mainline kernel.
Try the later kernel.

I tried both, still no luck. I used the latest kernel (2.6.39-rc7), but it's the same "brightness ignored, must be controlled by ACPI video driver"

hubx · 05-13-2011, 04:45 AM

Hi,

i use xbacklight to control the display brightness on my vaio.

try
xbacklight -set 0
xbacklight -set 100

PhoenixAndThor · 05-16-2011, 05:02 AM

I can confirm that xbacklight works for some machines, used to use it on and old thinkpad. If xbacklight doesn't work, then you're going to have to dive back into Ubuntu or Fedora and track down exactly what it is that makes the brightness control work on them, but not on Slack. I wish you a lot of luck in your hunt.

yuuko · 05-16-2011, 10:43 AM

It might not hurt to try appending 'acpi_osi=' to your kernel parameters.
Don't forget to run 'lilo' after editing 'lilo.conf'.