How to disable RTC Coin Cell Battery charging in Kernel?

Hello,

I have a Jetson Xavier NX and I would like to disable charging of RTC Coin Cell Battery.
I saw this post : Jetson Xavier NX, disable RTC battery charger and made the same modifications in the file ~/nvidia/nvidia_sdk/JetPack_4.6.3_Linux_JETSON_XAVIER_NX_TARGETS/Linux_for_Tegra/bootloader/t186ref/BCT/tegra194-mb1-bct-pmic-p3668-0001-a00.cfg

In this file, i added this line under the pmic.system.block[2] other commands :

pmic.system.block[2].commands[1].0x04.0x01 = 0x0;

The thing is when I run ./apply_binaries.sh and then do
./flash.sh “jetson-xavier-nx-devkit-emmc” “mmcblk0p1”
I still measure 3V on the battery connection after the flashing is done and after the reboot of my Jetson.
It has been suggested in the above linked post answer to also disable charging in Kernel, but I have no idea how to do it…
how can I put this commands when the kernel boots ?

i2cset -f -y 4 0x03c 0x04 0x08
i2cset -f -y 4 0x03c 0x04 0x00

If it is not the good way, how can I use the device tree options ?
I have never used device tree options.
Also, I have Ubuntu 18.04 installed on a VM on VMWare workstation, can it be the problem ?

I have a bit investigate on the forum, and I think that I should do a modification of the file in this directory
/nvidia/nvidia_sdk/JetPack_4.6.3_Linux_JETSON_XAVIER_NX_TARGETS/Linux_for_Tegra/kernel/dtb

I have done
dtc -I dtb -O dts -o output.dts tegra194-p3668-all-p3509-0000.dtb
Then I did gedit output.dts to see what is inside, but I have no idea what to put to be able to disable RTC Battery Charging ?

Thank you in advance for your help

Lucas

Sorry for the late response, have you managed to get issue resolved or still need the support? Thanks

please remove the “backup-battery” from kernel device tree.

Hello, thank you for your replies. I am currently using rechargeable battery, but I will try to use non rechargeable ones and remove the “backup-battery” from kernel device tree.

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