New sysfs interface for privacy screens

[Jingoo Han]

> On 10/6/19, 7:04 AM, Pavel Machek wrote:
>
> Hi!
>
> > > >> I have been looking into adding Linux support for electronic privacy
> > > >> screens which is a feature on some new laptops which is built into the
> > > >> display and allows users to turn it on instead of needing to use a
> > > >> physical privacy filter. In discussions with my colleagues the idea of
> > > >> using either /sys/class/backlight or /sys/class/leds but this new
> > > >> feature does not seem to quite fit into either of those classes.
> > > >
> > > > FWIW, it seems that you're not alone in this; 5.4 got some support for
> > > > such screens if I understand things correctly:
> > > >
> > > >   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=110ea1d833ad
> > > 
> > > Oh, I didn't realize it got merged already, I thought this was
> > > related...
> > > 
> > > So we've already replicated the backlight sysfs interface problem for
> > > privacy screens. :(
> > 
> > I guess... although the Thinkpad code hasn't added any standard
> > interfaces (no other laptop should be placing controls for a privacy
> > screen in /proc/acpi/ibm/... ). Maybe its not too late.
>
> There's new interface for controlling privacyguard... but perhaps we
> need better solution than what went in 5.4. Perhaps it should be
> reconsidered?

I agree with your opinion. I also think that better solution can be considered,
although there is already something in 5.4.

Best regards,
Jingoo Han

>
> Best regards,
>									Pavel
> -- 
> (english) http://www.livejournal.com/~pavelmachek
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