Screen brightness dimmed after blank

I’m running fedora 32 on a Lenovo p50 and using discrete graphics only. Graphics driver is nouveau.

I see that when the screen turns on again after a blank due to inactivity, the brightness is dimmer than before the blank.

I can see the actual_brightness field reflects this.

To repro:

$ cd /sys/class/backlight/nv_backlight
$ grep . *bright*
actual_brightness:90
brightness:90
max_brightness:100

$ sleep 1; xset dpms force off
# Screen blanks then I press a key to turn it back on

$ grep . *bright*
actual_brightness:37
brightness:90
max_brightness:100

Anyone else observe this behaviour?

Created a bug report for this here: https://bugzilla.redhat.com/show_bug.cgi?id=1845770