Bug 251844 - Controlling screen brightness (i2c, ddc, ...)
Summary: Controlling screen brightness (i2c, ddc, ...)
Status: Closed Not A Bug
Alias: None
Product: Base System
Classification: Unclassified
Component: misc (show other bugs)
Version: Unspecified
Hardware: Any Any
: --- Affects Some People
Assignee: freebsd-bugs (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2020-12-14 19:28 UTC by Hannes Hauswedell
Modified: 2025-02-04 12:53 UTC (History)
1 user (show)

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Description Hannes Hauswedell 2020-12-14 19:28:29 UTC
Linux folks have support for regulating screen brightness via software:
https://github.com/rockowitz/ddcutil

But it doesn't seem like this works on FreeBSD -- although in theory we have the required subsystems, or not?

The author of the tool has is willing to add FreeBSD support:
https://github.com/rockowitz/ddcutil/issues/118
but needs a little help from FreeBSD hackers. Could someone provide him with the required information?

Thank you very much!
Comment 1 Andriy Gapon freebsd_committer freebsd_triage 2020-12-14 22:48:53 UTC
Please use one or more of forums suggested here https://www.freebsd.org/community.html to discuss and promote your proposal.
Comment 2 Conrad Meyer freebsd_committer freebsd_triage 2020-12-15 02:28:53 UTC
DDC I2C support depends on GPU drivers providing an ioctl interface.  The FreeBSD nvidia driver *does not* provide the ioctls, but the Linux nvidia driver does (support is present in the binary blob, but not exposed to userspace).  I'm not sure if we have DDC/I2C ioctl support in either the Intel or AMD GPU drivers.
Comment 3 Andriy Gapon freebsd_committer freebsd_triage 2020-12-15 11:36:35 UTC
When drm drivers were in base they used to expose standard /dev/iic devices.
It no longer seems to be the case with the linuxkpi based drivers.
Comment 4 Hannes Hauswedell 2020-12-15 14:18:25 UTC
(In reply to Conrad Meyer from comment #2)

Thank you for responding to this! Such a change to the NVIDIA-driver would be very much appreciated! Would be very willing to help test this!

(In reply to Andriy Gapon from comment #3)
OK, seeing as these things were provided by drivers before and are not any more, is it not correct to assume that this is a FreeBSD issue and thus the STATUS of this problem report should be re-opened?
Comment 5 Andriy Gapon freebsd_committer freebsd_triage 2020-12-16 08:37:49 UTC
(In reply to Hannes Hauswedell from comment #4)
It's something that FreeBSD is missing , yes, but I doubt that a problem / bug report is appropriate here.

Think of "FreeBSD does not run on Apple silicon".
It's true and it may be a problem for someone.
But it is not a bug per se.
And opening a report for it would do very little to get the actual work done.

Same here.
Comment 6 ykla 2025-02-04 12:53:40 UTC
What's about it now?