ACPI_ASUS(4)

💖 acpi_asus — Asus Laptop Extras 💖

okay bestie, so this is ACPI_ASUS(4) from the Kernel Interfaces Manual, and it's literally the page that makes your old Asus laptop's weird little buttons actually do something. sit down, grab a boba, we're going in 🧋✨

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🌸 NAME 🌸

acpi_asus — Asus Laptop Extras

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🎀 SYNOPSIS 🎀

so there's two ways to get this driver living in your system, and it depends on the vibe you're going for.

Option 1: bake it right into the kernel. drop this line into your kernel configuration file:

device acpi_asus

Option 2: load it as a module at boot time. in that case, put this line in loader.conf(5):

acpi_asus_load="YES"

either one works, it's giving "choose your own adventure" 🦋

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✨ DESCRIPTION ✨

okay so here's the tea. the acpi_asus driver provides support for all the extra ACPI-controlled gadgets you find on recent Asus (and Medion) laptops — we're talking hotkeys, leds, all that cute stuff 💅

and the way it lets you play with things is through the sysctl(8) interface, so you can manipulate the brightness of the LCD panel and the display output state. no cap, that's the whole point.

hotkey events get passed along to devd(8) so they're easy to handle in userspace, and it all works out of the box with the default configuration in /etc/devd/asus.conf. iconic behaviour honestly 👑

currently, these Asus laptops are fully supported:

xxN
A1x
A2x
A3N
A4D
A6VM
D1x
J1x
L2B
L2D
L2E
L3C
L3D
L3H
L4E
L4R
L5x
L8x
M1A
M2E
M6N
M6R
S1x
S2x
V6V
W5A
Eee PC

and additionally, acpi_asus also supports the Asus-compatible ATK0100 interface found in Samsung P30/P35 laptops. not me being inclusive across brands 😭🫶

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🦋 SYSCTL VARIABLES 🦋

here's where it gets fun. these sysctls are currently implemented:

• hw.acpi.asus.lcd_brightness — makes the LCD backlight brighter or dimmer. higher values are brighter, so go off, crank that number ⭐
• hw.acpi.asus.lcd_backlight — turns the LCD backlight on or off. that's it, that's the whole job 💡
• hw.acpi.asus.video_output — sets the active display to use, according to a bitwise OR of these:
  • 0 — No display
  • 1 — LCD
  • 2 — CRT
  • 4 — TV-Out

heads up bestie: some models also support video switching via the generic acpi_video(4) driver. most models do not, though. so don't come for me if yours doesn't 🫠

defaults for these variables can be set in sysctl.conf(5), which is parsed at boot-time. set it and forget it, main character energy 💜

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🌈 SEE ALSO 🌈

acpi(4), acpi_asus_wmi(4), acpi_video(4), sysctl.conf(5), sysctl(8)

the acpi4asus Project, http://sourceforge.net/projects/acpi4asus/ 🌐

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💀 HISTORY 💀

the acpi_asus driver first appeared in FreeBSD 5.3. a true elder, we respect our ancestors 🙈

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👑 AUTHORS 👑

the acpi_asus driver and this manual page were written by Philip Paeps <philip@FreeBSD.org>. absolute legend, no notes 💖

inspiration came from the acpi4asus project started by Julien Lerouge, which maintains a driver implementing this functionality in the Linux kernel. cross-platform slay, we love to see it 🐧🤝🐡

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and that's the whole page, bestie!! mwah 💋 this was Debian's version, dated February 8, 2010, for ACPI_ASUS(4) — yeah she's vintage but she still eats ✨