Recently installed Ubuntu 18.04 after the automatic upgrade from 17.10 failed, resulting in my inability to turn on the system normally. After installing the OS the brightness controls on my laptop has stopped working. There are no brightness controls in the settings either in the new OS either. How can I get it to work?
If you are referring to the keys to change brightness up and down (in my laptop it is Fn+F11/F12):
I am running Xubuntu 18.04 and have struggled with the impossibility to control brightness using the Fn+F11/F12 keys since I installed it...
I just found out an option in the
Power Management
section, "Handle display brightness keys", which by default came deactivated. I just turned it on and the Fn+F11/F12 keys work as expected.Perhaps there is a similar option in the Power Management section for Ubuntu vanilla and other flavors.
For people having this problem on an HP Zbook Studio x360 Windows 10/ Ubuntu 18.04 dual boot. It appears this problem is caused by the following bug. The solution of @jttoivon which is found as a comment in this bug report appears to temporary solve the problem.
On Xubuntu 18.04 (Ubuntu with xfce desktop) my brightness problem finally solved.
I opened 'Onboard Settings' under the 'Settings' menu. If your desktop doesn't have one, you can download it from Software Center.
On the 'Onboard Preferences' window, click the Layout menu, then choose the 'Full Keyboard' (Desktop keyboard with edit and function keys). Click here to view the Onboard Settings window