read backlight settings from sysfs instead of applying dconf value

[danrobinson78]

There's a bunch of bugs open against a few different repositories in here some of which are the correct component, and some of which are not.
mate-desktop/mate-settings-daemon#165
mate-desktop/mate-desktop#306
#76

Looks like the underlying issue is that m-p-m is grabbing a stored value in dconf and applying it instead of just reading what's currently set in sysfs. Most other DEs don't apply any backlight settings on login. I can just log in, and the brightness controls reflect whatever the hardware is actually set to at that time. So there's no surprise change in brightness but I can adjust up or down the usual way from whatever it is.

systemd-backlight applies backlight settings on boot on most distros by default so even the boot messages and login screen are already set to whatever backlight I was using when I shut down, so having MATE try to change that on login is jarring.

It still probably makes sense to write the selected values to dconf so that we can change brightness based on AC/battery switch or things like that. But brightness shouldn't be changed just by logging in.

[lukefromdc]

Also remember the case of brightness accidently set to zero. This must never be repeated on a later login as it would then be difficult to get out of.

…

On 9/12/2021 at 9:19 AM, "Dan Robinson" ***@***.***> wrote: There's a bunch of bugs open against a few different repositories in here some of which are the correct component, and some of which are not. mate-desktop/mate-settings-daemon#165 mate-desktop/mate-desktop#306 #76 Looks like the underlying issue is that m-p-m is grabbing a stored value in dconf and applying it instead of just reading what's currently set in sysfs. Most other DEs don't apply any backlight settings on login. I can just log in, and the brightness controls reflect whatever the hardware is actually set to at that time. So there's no surprise change in brightness but I can adjust up or down the usual way from whatever it is. systemd-backlight applies backlight settings on boot on most distros by default so even the boot messages and login screen are already set to whatever backlight I was using when I shut down, so having MATE try to change that on login is jarring. It still probably makes sense to write the selected values to dconf so that we can change brightness based on AC/battery switch or things like that. But brightness shouldn't be changed just by logging in. -- You are receiving this because you are subscribed to this thread. Reply to this email directly or view it on GitHub: #364