How to apply a DSDT overlay patch?

[pupp_overflow]

TL;DR

Hei there!

How can I apply a DSDT overlay patch I've found for my device to enable screen backlight controls?

• Link to dev post https://hansdegoede.livejournal.com/24132.html
• Link to repo with DSDT patch https://fedorapeople.org/~jwrdegoede/acer-sw10-sw5-012/

I've tried loading the AML file via GRUB but AFAICT it's not working or is ignored.
I've upgraded my device BIOS version as required by the dev.

Full disclosure: I'm not an expert in all this kernel patching stuff, my attempts are pretty rough and tested right after some google fu!
Here below the GRUB config snippet I've added:

Code: Select all

# fix for readonly sd-card
GRUB_CMDLINE_LINUX_DEFAULT="sdhci.debug_quirks=0x10000"

menuentry "Start Fatdog64 tabdog" {
    echo Loading ...
    linux /vmlinuz rootfstype=ramfs savefile=direct:device:mmcblk1p3:fd64save-tabdog.ext4 coldplug
    acpi /dsdt-backlight.aml
    initrd /initrd
    echo Booting ...
}

dsdt-backlight.aml is the dsdt.aml file renamed from repo link. I've placed it in the root folder of the usb where grub.cfg is also present.

Some spec details
OS: FatDog64 811
Mod: Acer Switch 10 SW5-012-13TT
CPU: Intel Atom Z3735F
RAM: 2GB

Long version:

So after quite some time I'm back again in my pursuit for Linux!

I'm starting back from what was the situation left in this post, but I'm focusing on my blocking issue for a switch to linux.
I'm trying to make the backlight controls work on an Acer tablet/mini laptop (spec details above).
The backlight is 100% brightness all the time, causing very high eye strain during use. I've tried with xrandr as an alternative but is not sufficient unfortunately.

After some research I've found a post from a Fedora dev with my very same model who published a DSDT patch for the backlight drivers. The problem is I wasn't really aware of what a DSDT patch is.

After some more research I've found that DSDT patches can be applied via GRUB, so I've tried with the code posted above but it didn't work.

Am I naive thinking that it's possible to apply this DSDT in some easy way? Am I missing something?

Thank you all for any help and suggestions!

[FallOutBot31]

Hi!

I've installed Lubuntu in my system though I think the process would be the same in your case.

I successfully applied the DSDT overlay to my initrd.img by following the process in this link.
https://gist.github.com/franga2000/2154 ... nt-3382666

I skipped the part where he installed a new kernel.
Instead, I did a crude job of copying and pasting the initramfs-acer-sw10-sw5-012-dsdt-overlay.img to /boot using my file manager by granting it root access.

After that, I opened terminal then ran this code

Code: Select all

sudo su
cd /boot
mv initrd.img-5.15.0-41-generic initrd.img-5.15.0-41-generic.orig
cat initramfs-acer-sw10-sw5-012-dsdt-overlay.img initrd.img-5.15.0-41-generic.orig > initrd.img-5.15.0-41-generic

for the last 2 lines, you may want to change initrd.img-5.15.0-41-generic to the version of the kernel that you are using.

After that, reboot your tablet and then you can now change your backlight through the slider.

Hope that helps!