Backlight reset to 100% after DPMS off with Pascal-based cards

With 381.09 and backlight control finally working with Pascal-based cards, I’ve found a bug when waking up the screen.

If the screen is turned off via DPMS (i.e., not just blanked via an image file or the like), a subsequent wakeup will reset the backlight value to full brightness.

The previous value is “respected” in the way that it’s still set correctly (for instance, xbacklight -get and the sysfs node report the old value.) Changing the value by a step up or down pulls the brightness back to around the level (plus/minus the stepping value) before DPMS kicked in.

It looks like the driver is not correctly resetting the brightness value after the screen wakes up.

I can confirm the behaviour with 381.09 on my laptop.
It would be nice if this would be fixed in the final version of this driver.

I am happy brightness control finally works. Keep up the good work.

This was fixed with the next driver release, if I remember correctly. Closing up.