[PATCH 1/2] libbacklight: Fix backlight detection on recent kernels

[Daniel Stone]

Hi Armin,

On 8 February 2017 at 12:55, Armin Krezović <krezovic.armin at gmail.com> wrote:
> I don't know when it started happening, but recent kernels
> give different names for pci_device and backlight parent.
>
> pci_device is tied to the GPU PCI ID, while backlight parent
> is tied to the connector, rather than the GPU itself.
>
> On my system, I get the following (paths taken from actual
> strings that were parsed):
>
> pci_device: 0000:00:02.0
> parent: card0-eDP-1

This worries me a bit, since it removes checks which were there for a
reason: to make sure we actually picked the right backlight in the
presence of multiple backlights. I don't know what the right answer
is, but probably looking at what the X server / Mutter does would shed
some light on the matter.

I'm hesitant to push this for now, given that we're in a pretty deep freeze.

Cheers,
Daniel