Fix Linux Desktop brightness adjustment does not work

Working on the cause to start using Ubuntu. The desktop environment is gnome, but the brightness adjustment does not matter much to the desktop environment.

Ideas:

Whether gnome or unity, will try to take over the brightness adjustment, that is, to go to the/sys/class/backlight below to find brightness. So the brightness can not be adjusted probably categorized into two situations:

1.sys/class/backlight/below is empty, more in Nvidia and some tease than notebook.

2.sys/class/backlight/There are several, more common in the dual graphics notebook

Since all want to adjust brightness, must be the Linux as the main system to use, so first install the closed source drive, and then adjust the brightness of things.

The author of the situation is ThinkPad P51, using discreted graphic, the full disabling of the display, the output and operation by NVIDIA alone is responsible. This is the case 1, in which case the Nvidia driver takes over the brightness adjustment, but the default does not turn on the brightness adjustment function. Need to turn on nvidia brightness adjustment handler, how to do the following again.

Overall thinking summed up, probably is to find a way to let/sys/class/backlight below only a brightness, and is effective that one.

Job:

Scenario 1: For Nvidia alone, add the core parameters to the brightness adjustment handler on the line.

For non-Nvidia alone, kernel boot parameters in grub plus acpi_osi=linux basically solve the problem.

Scenario 2: This situation is considered to be forbidden alone, or to use Bumblebee, but the final idea of the same, think of a way to stay only a valid brightness in/sys/class/backlight, which is effective please echo to the brightness of the value of the test

The author's situation:

Nvidia Solo, Ubuntu 18.04, operates as follows:

1. Install at least 387 versions of the Nvidia closed source driver, the author uses 390.24 (brightness adjustment handler from 387 as a beta feature provided, default off)

2. Add parameters to the Nvidia kernel module in moprobe.conf, where you can find the file yourself with Whereis. Add the following contents

Options nvidia nvreg_enablebacklighthandler=1

3. Reload the kernel parameter, which means that the previous step takes effect

# Update-initramfs

4. Restart the computer, brightness should be normal, check/sys/class/backlight, the following is the only nvidia_0, the system appears brightness slider, brightness shortcut key effective.

The other situation is to look at the above ideas, double graphics users try to find ways to shield off the unique display, unless you say that you can work alone.

In general, there is no need to use any brightness plug-in, the adjustment is troublesome and wasted energy.

　　

Fix Linux Desktop brightness adjustment does not work