backlight(9)

backlight9

Backlight methods

Usage

device backlight

#include <backlight_if.h>

#include <sys/sys/backlight.h>

int

BACKLIGHT_GET_STATUS(device_t bus, struct backlight_props *props);

int

BACKLIGHT_SET_STATUS(device_t bus, struct backlight_props *props);

struct cdev *

backlight_register(const char *name, device_t dev);

int

backlight_destroy(struct cdev *cdev);

Overview

The backlight driver provides a generic way for handling a panel backlight.

Drivers for backlight system register themselves globally using the backlight_register() function. They must define two methods, BACKLIGHT_GET_STATUS() which is used to query the current brightness level and BACKLIGHT_SET_STATUS() which is used to update it.

Interface

BACKLIGHT_GET_STATUS(device_t bus, struct backlight_props *props)

Driver fills the current brightless level and the optional supported levels.

BACKLIGHT_SET_STATUS(device_t bus, struct backlight_props *props)

Driver update the backlight level based on the brightness member of the props struct.

Files

/dev/backlight/*

Releases

15 releases since FreeBSD 13.0-RELEASE; the text changed 3 times.

  1. 13.0–13.2
  2. 13.3–13.5
  3. 14.0–14.3
  4. 14.4–16.0

History

The backlight interface first appear in FreeBSD 13.0. The backlight driver and manual page was written by Emmanuel Vadot ⟨[email protected]⟩.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.