Forem: sureshsaragadam

ASUS TUF Gaming A16 (FA608WV) on Linux: Screen Brightness & Keyboard Backlight – A Deep Dive into a Dual-GPU ACPI Issue

sureshsaragadam — Sun, 25 Jan 2026 17:12:57 +0000

ASUS TUF Gaming A16 (FA608WV) on Linux
Screen Brightness & Keyboard Backlight — A Dual-GPU ACPI Case Study

System Overview

I am running Arch Linux on an ASUS TUF Gaming A16 (FA608WV) with the following configuration:

CPU / iGPU: AMD Ryzen AI 9 HX (Radeon 880M / 890M)

dGPU: NVIDIA RTX 4060 (Laptop)

GPU topology: Muxless dual-GPU system

Internal display panel is physically wired to the AMD iGPU

NVIDIA dGPU is used for rendering/offload

Display server: X11

Window manager: i3wm

Kernel: Linux 6.17.9-arch1-1

BIOS: FA608WV.305 (2024-11-25)

I run NVIDIA as the primary rendering provider (NVIDIA as Provider 0 in Xorg), which is a common setup for performance-focused Linux users.

Problem Summary

I am facing two related but distinct hardware control issues on Linux:

Screen hardware brightness control is unreliable / intermittent

Keyboard backlight does not work at all


❯ hostnamectl
  Static hostname: 9HX
        Icon name: computer-laptop
          Chassis: laptop 💻
Chassis Asset Tag: No Asset Tag
       Machine ID: 480d70398f004aa8b214c37b9314a6b2
          Boot ID: 3efa217afce64be188aa57f18a2efa83
 Operating System: Arch Linux                         
           Kernel: Linux 6.17.9-arch1-1
     Architecture: x86-64
  Hardware Vendor: ASUSTeK COMPUTER INC.
   Hardware Model: ASUS TUF Gaming A16 FA608WV_FA608WV
 Hardware Version: 1.0
 Firmware Version: FA608WV.305
    Firmware Date: Mon 2024-11-25
     Firmware Age: 1y 2month

Screen Brightness: Root Cause Only a single backlight interface is exposed:

Despite the internal panel being driven by the AMD iGPU, the kernel does not register the AMD DRM backlight (amdgpu_bl0). This forces Linux to fall back to an ACPI / Embedded Controller (EC) backlight path exposed via NVIDIA WMI.

This EC-based backlight path is:

Firmware-dependent

Power-state sensitive

Intermittent across boots and suspend/resume

As a result, hardware brightness control works inconsistently and tools like xbacklight are unusable because no DRM backlight exists.

❯ ls -l /sys/class/backlight/
total 0
lrwxrwxrwx 1 root root 0 Jan 25 19:43 nvidia_wmi_ec_backlight -> ../../devices/pci0000:00/PNP0C14:00/wmi_bus/wmi_bus-PNP0C14:00/603E9613-EF25-4338-A3D0-C46177516DB7-0/backlight/nvidia_wmi_ec_backlight

Rendering path:


❯ glxinfo | grep "OpenGL renderer"
OpenGL renderer string: NVIDIA GeForce RTX 4060 Laptop GPU/PCIe/SSE2

Xorg provider state:

❯ xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x1b7 cap: 0x1, Source Output crtcs: 4 outputs: 4 associated providers: 1 name:NVIDIA-0
Provider 1: id: 0x1eb cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 4 outputs: 9 associated providers: 1 name:modesetting

GPU layout confirms a classic AMD-panel / NVIDIA-render configuration:

❯ lspci -nn | grep -E "VGA|3D|Display"
64:00.0 VGA compatible controller [0300]: NVIDIA Corporation AD107M [GeForce RTX 4060 Max-Q / Mobile] [10de:28e0] (rev a1)
65:00.0 Display controller [0380]: Advanced Micro Devices, Inc. [AMD/ATI] Strix [Radeon 880M / 890M] [1002:150e] (rev c1)

GPU layout confirms a classic AMD-panel / NVIDIA-render configuration:


❯ lspci -k | grep -A3 -E "VGA|Display"
pcilib: Error reading /sys/bus/pci/devices/0000:00:08.3/label: Operation not permitted
64:00.0 VGA compatible controller: NVIDIA Corporation AD107M [GeForce RTX 4060 Max-Q / Mobile] (rev a1)
    Subsystem: ASUSTeK Computer Inc. Device 3818
    Kernel driver in use: nvidia
    Kernel modules: nouveau, nvidia_drm, nvidia
--
65:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Strix [Radeon 880M / 890M] (rev c1)
    Subsystem: ASUSTeK Computer Inc. Device 3818
    Kernel driver in use: amdgpu
    Kernel modules: amdgpu

Keyboard Backlight: Root Cause

The kernel exposes a keyboard backlight interface:


/sys/class/leds/asus::kbd_backlight

However, writing brightness values produces no physical effect. This indicates that while the interface exists, no functional EC command is mapped for the FA608WV model. In other words, the required ASUS EC/WMI quirk for keyboard backlight control is missing.

Because this is a kernel-level issue, userspace tools such as asusctl cannot fix it.

Required Kernel Support (Conclusion)

For the ASUS TUF Gaming A16 (FA608WV, 2025) to work reliably on Linux, the most important fixes are required at the kernel level, not in window managers or userspace tools. The primary issue lies in the drm/amdgpu subsystem, where the kernel currently skips registering the AMD DRM backlight (amdgpu_bl0) despite the internal display panel being physically wired to the AMD iGPU. This forces Linux to fall back to an ACPI/EC-based backlight path that is firmware-dependent and unstable. To ensure consistent screen brightness control, the kernel needs a deterministic backlight selection policy—either by restoring AMD DRM backlight registration on this model or by introducing a DMI-based exception so that AMD-driven panels always expose a native DRM backlight interface.

The second required update concerns ASUS EC/WMI support in asus-wmi / asus-nb-wmi. Although the kernel exposes a keyboard backlight device (asus::kbd_backlight), it performs no actual EC action on the FA608WV, indicating a missing model-specific EC quirk. Without this, keyboard backlight control cannot function regardless of userspace configuration or tools like asusctl. Once these kernel-level fixes are in place—restoring AMD DRM backlight and adding the correct EC mapping for keyboard lighting—userspace utilities and desktop environments will work consistently without workarounds. Until then, brightness and keyboard lighting on this 2025-era laptop should be expected to remain best-effort rather than fully reliable.

On ASUS TUF Gaming A16 (FA608WV), the kernel skips AMD DRM backlight registration despite the panel being AMD-driven and exposes a non-functional ASUS EC keyboard backlight; restoring deterministic AMD backlight handling and adding a model-specific EC/WMI quirk are required for reliable brightness and keyboard lighting support.

good luck for those who purchased this laptop for Linux use case...me spent lot of money on this laptop and got noting to do other than waiting for an early update for this model..

“ChatGPT Navigation Using Default Keyboard Shortcuts (No Extensions Needed)”

sureshsaragadam — Fri, 07 Nov 2025 03:07:13 +0000

ChatGPT Navigation Using Default Keyboard Logic (No Extensions Needed)

Most people use a mouse or browser extensions like Vimium to scroll ChatGPT. But what if you're on a new system, a public computer, or a clean OS install with no plugins?

The key is understanding how browsers handle focus and a hidden feature called Caret Browsing.

💡 Why Page Up/Page Down Don’t Work While Typing

When you're typing in ChatGPT, the browser places the focus inside the text box.
In this state:

Arrow keys, Page Up/Down, etc. only affect the text area, not the page.

The rest of the ChatGPT conversation window is treated as a background element.

That’s why scrolling with the keyboard doesn’t work, but the mouse still can.

This isn’t a ChatGPT limitation—it’s how web focus works in every browser.

💡 The Turning Point: Caret Browsing (F7)

Browsers like Firefox and Chrome have a built-in accessibility feature called Caret Browsing (toggle using F7).

What it does:

✔ Places a blinking text cursor (caret) on the webpage itself—not just inside inputs
✔ Makes the webpage behave like a readable text document
✔ Allows the page to be navigated using arrow keys and Shift + Arrow, even while typing in ChatGPT
✔ You no longer need to unfocus the text box or use a mouse to scroll

In simple terms:
Caret Browsing lets the keyboard control the entire page instead of just the input box.

💡 Why This Matters

This method is powerful because:

✅ It uses only default browser behaviour (works on any system)

✅ No need for Vimium, scripts, or custom keybindings

✅ Works on Linux, Windows, macOS, i3wm, GNOME, KDE, etc.

✅ Perfect for people who depend on efficiency and portability

💡 Final Takeaway

The trick isn’t a shortcut—it’s a shift in how the browser sees the page.

Turn on Caret Browsing (F7) → The ChatGPT page becomes keyboard-friendly → You can scroll and navigate without leaving the typing box or using a mouse.

make use of => Shift + Arrow Keys while caret browser is activated with F7 in Firefox

and use F6 to switch between text box and address bar

Ctrl + L to go to Address bar..

Once you understand this concept, you can use ChatGPT efficiently on any machine, anywhere, with default keyboard minimizing hand movement when work is under focus.

Privacy Policy of Fibclock App

sureshsaragadam — Thu, 12 Jun 2025 17:53:54 +0000

Fibonacci Clock is developed by Saragadam Suresh and is provided as a free application. This app is a variant of the Fibonacci Clock concept and does not collect, store, or share any user-specific data.
Information Collection and Use

The Fibonacci Clock app does not collect any personal or sensitive information from its users. Specifically:

No personal data (e.g., name, email, or phone number) is collected.
No device information (e.g., location, IP address, or hardware data) is accessed.
No usage analytics or tracking mechanisms are employed.

Third-Party Services

This app does not integrate or use any third-party services that could collect data from users.
Changes to This Privacy Policy

The privacy policy may be updated from time to time. Any changes will be posted here to keep you informed.
Contact Us

If you have any questions or concerns regarding this Privacy Policy, feel free to reach out:
Email: saragadamsuresh@gmail.com

Effective Date: [12-6-2025]

Dual Monitor Setup in Linux in i3wm

sureshsaragadam — Tue, 22 Oct 2024 17:36:35 +0000

Challenges

I keep disconnecting the Extended monitor when required, keep the dpi settings sync with both the Laptop and Extended Monitor, so that both the Laptop and Extended monitor feel with the same dpi resolution

- Need to setup a 4k Monitor as extended Monitor in Linux

tools needed xrandr

xrandr automatically detects the external monitor, First after the 4k monitor detected as extended monitor i noticed that my font size is too small for the 4k Monitor, so we need to adjust the 4k Monitor font size to the desired dpi with the .Xresources file in my home directory.

Create a file .Xresources and make an entry in this file to set the desired dpi

Xft.dpi: 144

xrdb -merge .Xresources

So the settings of the Xft.dpi to 144 in the file .Xresources IN MY SCENARIO it is 144 you can adjust to your desired value.

Now after adjusting the Dpi i found that Laptop resolution is
not working as desired, So i need to scale and test the laptop dpi with xrandr to the desired settings from terminal first before applying the settings.

My working i3wm configuration

workspace 1 output eDP
workspace 2 output DP-1-0
workspace 3 output HDMI-A-0
# Moving workspaces between screens 

exec --no-startup-id feh --bg-fill /home/*user*/Pictures/Wallpapers/laptop.jpg
exec --no-startup-id xrandr  --output eDP --primary --mode 1920x1080 --scale 1.6 --output HDMI-A-0 --off --output DP-1-0 --off


# This is the configuration for the BENQ Programmer Series Monitor
bindsym $mod+n exec --no-startup-id "xrandr --fb 7680x2560 --output DP-1-0 --mode 3840x2560 --scale 1 --pos 0x0  --output eDP --primary --mode 1920x1080 --scale 1.6 --pos 3840x0 --output HDMI-A-0 --off ;  feh --bg-fill /home/*user*/Pictures/Wallpapers/laptop.jpg  --bg-fill /home/suresh/Pictures/Wallpapers/benq.png"

bindsym $mod+m exec --no-startup-id "xrandr --fb 3840x2560 --output DP-1-0 --primary --mode 3840x2560 --pos 0x0 --rotate normal --output eDP  --off --output HDMI-A-0 --off; feh --bg-fill /home/suresh/Pictures/Wallpapers/benq.png"

bindsym $mod+l exec --no-startup-id "xrandr  --output eDP --primary --mode 1920x1080 --scale 1.6 --output HDMI-A-0 --off --output DP-1-0 --off; feh --bg-fill /home/*user*/Pictures/Wallpapers/laptop.jpg"

i have three different shortcuts to work with only extended monitor, or only laptop or to work with both laptop and extended monitor

$mod+m $mod+l $mod+n respectively

Planning my Linux Homelab

sureshsaragadam — Sat, 16 Mar 2024 17:18:44 +0000

Task 1 Enough Research and Planning.
Task 2 Prepare a roadmap - or a blue print

I am planning to setup up a HOME-LAB in Linux using open-source tools, and further extend the home-lab to my eCommerce web-server project and later an application server project.

Here we are, setting up the initial goals...

Identify the Hardware required for home-lab
setup your router and switches
Plan network topology and vlan
Setup a DNS Server
Setup a NAS Server
Setup proxy server
Setup ntop,
Setup Nagios Server
Setup Graylog Server
Setup Backup Server
Setup web-server
setup application server.

This is a long journey to go, let us achieve one after the other. i keep publishing my tasks updated.