On 11/17/2016 04:31 PM, David C. Rankin wrote: > All, > > Laptop: HP 8760w, Quadro 3000M, nvidia-340xx packages. > > The driver works perfectly (no errors in Xorg.0.log), but I have no way to > control the screen brightness. I've followed the suggestions in: > > https://wiki.archlinux.org/index.php/NVIDIA/Tips_and_tricks > > but I still have no backlight control. Using the laptop function keys, the > values in /sys/class/backlight/acpi_video0/brightness are properly set, e.g. > > $ cat /sys/class/backlight/acpi_video0/brightness > 8 > > (now tap the [func][F9], brightness lower, twice) > > $ cat /sys/class/backlight/acpi_video0/brightness > 6 > > (actual_brightness value tracks brightness) > > $ cat /sys/class/backlight/acpi_video0/max_brightness > 20 > > This works with OR without /etc/X11/xorg.conf.d/20-nvidia.conf: > > Option "RegistryDwords" "EnableBrightnessControl=1" > > Does anyone have any suggestions on anything else to try before I start > loading the aur nvidia-bl or nvidiabl packages? I don't mind adding more > software, but if there are a few more tweaks to try before going that route, I > would like to try them first. Anybody get backlight working with a similar > model laptop? > Let me add to this, that powerdevil is seeing the screen brightness changes and Udev is evidently applying them correctly. For example, pressing the function key to raise/lower brightness seems to generate the correct log entries: Nov 17 23:36:37 seidr org_kde_powerdevil[710]: powerdevil: Screen brightness value: 6 Nov 17 23:36:37 seidr org_kde_powerdevil[710]: powerdevil: Screen brightness value max: 20 Nov 17 23:36:37 seidr dbus[334]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper) Nov 17 23:36:37 seidr org_kde_powerdevil[710]: powerdevil: set screen brightness value: 7 Nov 17 23:36:37 seidr org_kde_powerdevil[710]: powerdevil: Screen brightness value max: 20 Nov 17 23:36:37 seidr dbus[334]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper' Nov 17 23:36:37 seidr org_kde_powerdevil[710]: powerdevil: Udev device changed "/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/backlight/acpi_video0" "/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/backlight/acpi_video0" And, as noted above, the values in /sys/class/backlight/acpi_video0/brightness are changing as they should. I'll give both the aur packages a try (I have both built -- but the nvidiabl package is currently disowwned and needs a maintainer if anyone is interested) -- David C. Rankin, J.D.,P.E.
