Control: tag -1 - patch On Fri, Dec 20, 2013 at 22:27:22 -0500, Mattthew Gabeler-Lee wrote: > In gnome, changing the backlight brighness on many intel integrated chips, > esp. those in Dell and some HP laptops, is very slow. Changing the > backlight by a single step can cause the X environment to be unresponsive > for several seconds. > > This has been discussed on the Ubuntu launchpad in at least two tickets: > > https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/847001 > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/828296 > > The second ticket has both a patch (which I have not tested but looks simple > enough) and a workaround, which I have confirmed works for me. > > The workaround (add acpi_backlight=vendor to kernel command line) causes > this Xorg log line: > [ xxxxx.xxx] (--) intel(0): found backlight control interface /sys/class/backlight/acpi_video0 > to become this (for me, presumably something slightly different for non-Dell systems): > [ xxxxx.xxx] (--) intel(0): found backlight control interface /sys/class/backlight/dell_backlight > and the backlight responds with no perceivable lag or sluggishness. > Please report this upstream at bugs.freedesktop.org following the instructions at https://01.org/linuxgraphics/documentation/how-report-bugs and let us know the bug number for tracking. Cheers, Julien
Attachment:
signature.asc
Description: Digital signature