git: 4decda9797 - main - [hb][config]: Mention backlight(9)

The branch main has been updated by fernape:

URL: https://cgit.FreeBSD.org/doc/commit/?id=4decda97972ecd036ea44f0f603c3cbb3133ca97

commit 4decda97972ecd036ea44f0f603c3cbb3133ca97
Author:     Fernando Apesteguía <fernape@FreeBSD.org>
AuthorDate: 2023-11-14 14:25:30 +0000
Commit:     Fernando Apesteguía <fernape@FreeBSD.org>
CommitDate: 2023-11-14 14:25:30 +0000

    [hb][config]: Mention backlight(9)
    
    Add a mention to backlight(9) and backlight(8) in the configuration chapter.
---
 documentation/content/en/books/handbook/config/_index.adoc | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/documentation/content/en/books/handbook/config/_index.adoc b/documentation/content/en/books/handbook/config/_index.adoc
index f7d9cc27e2..3b49877eee 100644
--- a/documentation/content/en/books/handbook/config/_index.adoc
+++ b/documentation/content/en/books/handbook/config/_index.adoc
@@ -1234,6 +1234,18 @@ And add this line to [.filename]#/boot/loader.conf# to load it at boot:
 acpi_ibm_load="YES"
 ....
 
+An alternative to the man:acpi_video[4] module is the man:backlight[9] driver.
+It provides a generic way for handling a panel backlight.
+The default GENERIC kernel includes this driver.
+The man:backlight[8] utility can be used to query and adjust the brightness of
+the panel backlight.
+In this example the brightness is decreased by 10%:
+
+[source,shell]
+....
+% backlight decr 10
+....
+
 [[cpu-power-management]]
 === CPU Power Management