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Date: Fri, 27 Mar 2015 16:01:13 +0100
Message-ID: <CACyC=qZAhL3RPqErQh1BjjrhkbvmLXnrVT4i0LEtT10vbjVT2w@mail.gmail.com>
Subject: [PATCH] Adding backlight support for the i915 driver.
From: "Ranjan1018 ." <214748mv@gmail.com>
To: FreeBSD CURRENT <freebsd-current@freebsd.org>
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This  patch exposes the backlight support  via a sysctl:

set the backlight to 10%:

# sysctl hw.dri.0.i915_backlight=10

hw.dri.0.i915_backlight: 25 -> 10

set the backlight to 50%:

# sysctl hw.dri.0.i915_backlight=50

hw.dri.0.i915_backlight: 10 -> 50

decrease  the current backlight value:

# sysctl hw.dri.0.i915_backlight=-1000

hw.dri.0.i915_backlight: 50 -> 43

increment the current backlight value:

# sysctl hw.dri.0.i915_backlight=1000

hw.dri.0.i915_backlight: 43 -> 51

# sysctl hw.dri.0.i915_backlight=1000

hw.dri.0.i915_backlight: 51 -> 60

I am running this path on for about a week without issue.

This path can be found at:
https://github.com/maurizio-emmex/i915_backlight_freebsd

I thank Elizabeth Myers, elizabeth at interlinked dot me, for the idea of
adding the backlight support for the i915 driver and for the original patch.

Regards,
Maurizio