Rebuilding a PI Home Assistant kiosk

Back in 2023 I set up a raspberry pi 4 running chromium in kiosk mode to show home assistant dashboard on a wall mounted screen.

It used a PoE converter for power and connects therefore via internet.

However - even with ram disks - an SD card has a finite lifetime in a pi. It finally died.

The rebuild

Updated hardware:

• Raspberry Pi 5 4GB
• Waveshare PoE M.2 hat
• Disk - Crucial P310 SSD - 2TB - M.2 2230 - PCIe 4.0
• Screen - the original Pi 1.1 7" touchscreen from the previous build. You will need the Pi 5 compatible "Display Cable" - and note - the display and camera cables look very similar - but they are not the same - luckily it says either Camera or Display on the cable.

Install

• Use raspberry pi flasher to choose the 64 bit full desktop version.
• Set up user and ssh keys in options - no wifi - this is PoE so will be ethernet
• Install to the SSD
• Install the SSD to the hat and the hat on the pi and boot the pi
• Connect the display cable to Cam/Disp 0 port on the pi and to the screen
• Connect 5v power and ground pins from the adapter to the GPIO 5v and GND headers (if you look at the pi with the ports nearest you and the GPIO header on the right - then the first three pins from the top right corner moving towards the front are 5V, 5V and GND - so - use second and third pins).
• After boot update apps (apt update && apt full-upgrade)

Configuration

This is a lot simpler than it used to be.

On boot it auto logs in to the desktop.

There are some changes to suit my dashboard:

Portrait mode

You can change this manually (to test) with:

wlr-randr --output DSI-1 --transform 90

On the pi5 install - the screen display and the touchscreen turn together - so we don't need to turn the touchscreen at all.

To make it permanent:

Edit the file .config/labwc/autostart (create if not present) and add the same line.

Add a 1 second sleep afterwards - I found that without that it would move on before the screen completed its rotateion.

Chromium in kiosk mode

At the end of the autostart - add the following:

chromium URL_OF_YOUR_HOME_ASSISTANT \
    --kiosk \
    --noerrdialogs \
    --disable-infobars \
    --no-first-run \
    --enable-features=OverlayScrollbar \
    --start-maximized \
    --enable-features=WebContentsForceDark &

The last line is only needed for forcing dark mode.

Custom SSL

My home net uses a local CA - this was done before letsencrypt supported dns01 challenges - which I would recommend now.

But - if you need to add a custom CA - then:

Copy the CA cert (pem format) to /usr/local/share/ca-certificates/ - and the filename must end .crt Then run:

sudo update-ca-certificates

Test with openssl:

openssl s_client -connect URL_OF_YOUR_HOME_ASSISTANT_INCLUDING_PORT -CApath /etc/ssl/certs

Then we need to make chromium trust it - we'll add it to the kiosk user<s nssdb:

sudo apt install libnss3-tools

certutil -d sql:$HOME/.pki/nssdb -A -t "C,," -n "Name of CA" -i /usr/local/share/ca-certificates/filename_of_ca.crt

You can list the contents of the nssdb with:

certutil -d sql:$HOME/.pki/nssdb -L

VNC

Use raspi-config to enable VNC (under interfacing options > VNC).

This starts wayvnc - and the service will read the config from /etc/wayvnc

Mine listened on IPv6 by default. If you prefer IPv4 - change /etc/wayvnc/config

Change the line:

address = ::

to

address = 0.0.0.0

and restart the service with sudo systemctl restart wayvnc.

You can check it with:

ss -lntp | grep 5900

Finishing

Currently - it is up and running. The only issue is that it takes a few seconds after chromium starts before it stops saying "no internet" and shows the dashboard.

That's fine for now - I don't reboot it very often.