From: Kirill A. Korinsky <kirill@korins.ky>
Subject: Re: sys/qcdpc: blank eDP panels during suspend
To: Mark Kettenis <mark.kettenis@xs4all.nl>
Cc: tech@openbsd.org
Date: Mon, 05 Oct 2026 22:20:07 +0200

On Mon, 05 Oct 2026 21:46:37 +0200,
Mark Kettenis <mark.kettenis@xs4all.nl> wrote:
> 
> > Date: Mon, 05 Oct 2026 16:17:09 +0200
> > From: Kirill A. Korinsky <kirill@korins.ky>
> > 
> > and here I belive the correct diff.
> 
> 
> So as I indicated earlier today, I have some questions about this
> diff.
> 
> * What does this command actually do?  I thought I had a copy of the
>   relevant standard somewhere, but I haven't found it yet.  The name
>   of the command suggests that it blanks the display.  But what we
>   actually want is to power down the display...
> 
> * Does this disable the backlight?
> 
> * Do all eDP panels support this command?  As far as I can tell the
>   Linux kernel doesn't use it.  That could mean that it doesn't work
>   across the board.
> 
> At some point I looked into powering off the panel in my vivobook.
> But this Samsung panel seems to require some specific power sequencing
> to turn it back on.  I'll see if I can find that tree again...
> 

I had tested it only with my Honor and it blacks it's panel on zzz.

And I have no idea about other eDP panels or does it power it off.

-- 
wbr, Kirill