> Date: Thu, 22 May 2025 18:51:22 +1000
> From: Jonathan Matthew <jonathan@d14n.org>
> 
> On Thu, May 22, 2025 at 06:06:48AM +0000, Lucas Gabriel Vuotto wrote:
> > On Thu, May 22, 2025 at 04:18:37AM +0000, Lucas Gabriel Vuotto wrote:
> > > Not the same problem, but problems nevertheless. Quoting
> > > https://marc.info/?l=openbsd-misc&m=168377287112603&w=2
> > > 
> > > > Suspend and hibernate works. Lidaction works. Internal mic doesn't work
> > > > but audio recording does work with a headset. Webcam works. vmm works.
> > > > 
> > > > Turning down the screen brightness with the keyboard does turn the whole
> > > > screen black for an instant when getting at low values:
> > > > 
> > > > display.brightness=100.00%
> > > > display.brightness=75.39%
> > > > display.brightness=57.13%
> > > > display.brightness=42.46%
> > > > display.brightness=32.14%
> > > > display.brightness=23.41%
> > > > display.brightness=17.06%
> > > > display.brightness=12.30%
> > > > display.brightness=8.72%
> > > > display.brightness=5.95%
> > > > display.brightness=4.76%
> > > > display.brightness=3.97% # single black screen blink starts here
> > > > display.brightness=2.77%
> > > > display.brightness=1.98%
> > > > display.brightness=0.79%
> > > > display.brightness=0.00%
> > > 
> > > That went away with this patch. As a nice side-effect, my screen doesn't
> > > jump to full brightness the very first time I use any brightness button
> > > and I have more brightness levels:
> > 
> > Actually, now my laptop jumps to full brightness everytime I connect or
> > disconnect the AC.
> 
> Interesting, mine jumps to very low brightness when I connect or disconnect
> the AC.  I'm not sure where those brightness changes come from.

I wonder if instead of disabling the acpithinkpad(4) brightness button
events, we should disable the acpivout(4) based brightness control
functionality on these machines.

Or perhaps there is more acpithinkpad(4) functionality that needs to
be disabled on these machines.

You really need to understand all the moving parts to work on this...