[Solved] Full UART Issue with newer kernel

[shyne]

Hi,

With latest update I have an issue with UART, last working kernel is linux-rpi-6.1.27-1-armv7h
Since every kernel update result with no working UART.

Anyone know what's happening please?

Here is my config.txt

# See /boot/overlays/README for all available options
dtoverlay=pi3-disable-wifi
dtoverlay=pi3-disable-bt
enable_uart=1

dtparam=i2c_arm=on

#gpu_mem=64
gpu_mem=16

initramfs initramfs-linux.img followkernel

And cmdline.txt
root=/dev/mmcblk0p2 rw rootwait selinux=0 plymouth.enable=0 smsc95xx.turbo_mode=N dwc_otg.lpm_enable=0 elevator=noop ipv6.disable=1 fsck.repair=yes

[shyne]

Does anyone else have the same problem?

[graysky]

Post a test command that uses UART that fails for others to try. Also, your config.txt is a bit old. Recommend that you diff it against /boot/config.txt.pacnew

[shyne]

Thanks for your message, you were right, my config file is a bit old. However, updating it alone did not resolve the issue.

The cause of my problem was a systemd service lauching a serial console on uart0.
Here is the command to fix the issue: systemctl mask serial-gettyttyAMA0.service

[karog]

[quote="shyne"]Here is the command to fix the issue: systemctl mask serial-gettyttyAMA0.service[/quote]

Or maybe look in cmdline.txt and set console=AMA0?

[shyne]

I don't need a linux console on ttyAMA0.
I have a rpi enocean module connected to uart0 (ttyAMA0 on my host)

Maybe it's possible to disable serial console with a kernel cmd, I don't know how to do it.