How to disable HDMI on raspberry pi zero 2W ?

[moonlight83340]

Description

I have a raspberry pi zero 2W using kirkstone firmware, and I would like to disable HDMI to save power in a project.
I would like to do that on device tree with yocto build but I'm unable to make it work.

Steps to reproduce the issue:
I have try something like that :

/dts-v1/;
/plugin/;

/ {
    compatible = "brcm,bcm2835";

    fragment@0 {
        target = <&hdmi>;  // Remplace par le bon nom de nœud
        __overlay__ {
            status = "disabled";
        };
    };
};

I was thinking that it should be sufficient but the HDMI keep working.

Describe the results you received:
The HDMI still power on.

Describe the results you expected:
I would like the HDMI to be power off at start.

I have check the status with :
cat /proc/device-tree/soc/hdmi@7e902000/status
And status is okay so it's normal that HDMI isn't power off.

I have tried on raspi OS to simply power off the screen using the boot/config.txt adding this line :
dtoverlay=vc4-kms-v3d,nohdmi

I also tried following this step :
https://kittenlabs.de/blog/2024/09/01/extreme-pi-boot-optimization/
And so adding this lines to the boot/config.txt

# disable HDMI (saves power)
dtoverlay=vc4-kms-v3d,nohdmi
max_framebuffers=1
disable_fw_kms_setup=1
disable_overscan=1

# disable composite video output
enable_tvout=0

I can't reproduce the same with my kirkstone firmware.

I don't have so much experience with device tree so I'm bit lost 😅
I hope I made it clear, thanks.

PS: On the device tree I noticed that HDMI should be disable by default :

		hdmi@7e902000 {
			compatible = "brcm,bcm2835-hdmi";
			reg = <0x7e902000 0x600 0x7e808000 0x100>;
			reg-names = "hdmi\0hd";
			interrupts = <0x02 0x08 0x02 0x09>;
			ddc = <0x1c>;
			clocks = <0x1b 0x09 0x1b 0x0d>;
			clock-names = "pixel\0hdmi";
			dmas = <0x0b 0x9000011>;
			dma-names = "audio-rx";
			status = "disabled";
			power-domains = <0x13 0x05>;
			hpd-gpios = <0x07 0x1c 0x01>;
			phandle = <0x32>;
		};

But I noticed also this :

	chosen {
		bootargs = "coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1";
	};

I don't know if it's relevant.