>> On Tue, Jul 22, 2014 at 8:42 AM, Hans de Goede <hdegoede@xxxxxxxxxx> > Bertrik, can you try blacklisting the samsung-laptop module, then > check /sys/class/backlight, the samsung_laptop dir should be gone > replaced by an acpi_video0 (or some such) dir. Please try if that > works. If that does not work, try booting with both the module > blacklisted and "acpi_backlight=vendor" on the kernel commandline, > then you should see only the intel-backlight under /sys/class/backlight > and things should work. With linux kernel v3.14 and the samsung_laptop module blacklisted, I indeed see a /sys/class/backlight/acpi_video0, but changing brightness by writing (as root) to the brightness file does not have an effect. Additionally, with the acpi_backlight=vendor kernel command line option, there is only an intel_backlight directory in /sys/class/backlight. Brightness does work using "brightness up and down" function keys, with 'udevadm monitor' I can see it uses the intel_backlight: bertrik@netbook:~$ udevadm monitor monitor will print the received events for: UDEV - the event which udev sends out after rule processing KERNEL - the kernel uevent KERNEL[40.375921] change /devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight (backlight) UDEV [40.503704] change /devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight (backlight) With kind regards, Bertrik Sikken _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
