brightness control stopped working

[Jan Bramkamp]

On 27/10/15 22:32, aeuii at posteo.de wrote:
> Hello freebsd-acpi@,
>
> I have lenovo ThinkPad Edge E145 laptop and the LCD brightness control
> stopped working somewhere between 10.2-RELEASE and 10.2-RELEASE-p6.
>
> I used to adjust the brightness using Fn-☼- and Fn-☼+ buttons and it
> always worked (during boot, in X, text console).  Now, it works only
> in the loader, before the system boots.
>
> I tried alternative methods listed below, but non had any effect.
>
> Please help! ;)
>
> Thank you in advance,
> Stefan
>
>
> ** acpi_call
>
> acpi_call -v -p '\VBRU'
>
> Path: \VBRU
> Number of arguments: 0
> ioctl: Device not configured
>
> no effect

Is the acpi_call kernel module loaded?

> ** acpi_ibm
>
> sysctl dev.acpi_ibm.0.lcd_brightness=7
>
> values change, but no effect
>
>
> ** acpi_video
>
> sysctl hw.acpi.video.lcd0.brightness=50
> hw.acpi.video.lcd0.brightness: 50 -> #
>
> no effect
>
>
> pressing Fn+(sun)+- buttons has no effect, but logs:
>
> can't evaluate \134_SB_.PCI0.VGA_.LCD_._BQC - AE_NOT_FOUND
If the buttons generate events for devd you can execute whatever 
commands work for you. `cat /var/run/devd.pipe` logs all events consumed 
by devd from /dev/devctl. If the acpi_ibm module generates events for 
the function keys the output of said command will log them. The 
key-value pairs contain all the information needed to write matching 
event handlers in devd.conf.

Did you try xbacklight? The changes between 10.2-RELEASE and 
10.2-RELEASE-p6 shouldn't break your backligh controls. However lots of 
ports changed in that timeframe and maybe one of those changes e.g. a 
X.org driver update caused your problem.