[systemd-devel] [PATCH v2] backlight: let the administrator override clamping

Lennart Poettering lennart at poettering.net
Tue Jan 27 18:41:17 PST 2015

On Sun, 18.01.15 11:34, Topi Miettinen (toiwoton at gmail.com) wrote:

> On my computer, the minimum brightness enforced by clamping in
> backlight is too bright.
> Add a new option to override clamping in unit file. While at it, describe
> the clamping in documentation.

I must say that like David I am not too convinced of the idea to allow
disabling the clamping, but well...

Since we look at the udev device anyway, I'd be willing to merge a
patch that reads a new property ID_BACKLIGHT_CLAMP or so which takes a
bool. If the prop is missing it is assumed to be true. 

The backlight code could then look for this property and skip the
clamping if the bool is true. THat way you could add a udev rule that
sets the propery and be happy...

I think binding this to a udev property is much better than a command
line parameter, since this is intrinsicly device-bound... 

I figure this should be no more than a 5 line patch or so...


Lennart Poettering, Red Hat

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