Alternate device tree Examples:
Each folder contains a .dts file and a README showing the GPIO pin mappings.
Copy the desired .dts file to the build-trees folder and follow the readme there to build the device-tree binaries.
There are instructions at the end of that document on how you can use a custom .dtb and make it permanent across reboots and kernel upgrades.
The issue with using these trees is that if the upstream device tree or includes is modified you need to manually rebuild these trees.
EG any changes to the upstream sun20i-d1-mangopi-mq-pro.dts source needs to be detected and applied too. You need to examine file histories to do this.
- Fortunately this should not be an issue in practice; the kernel should remain very stable going forward. Ubuntu 24.04.1 is a LTS release..
The authors personal advice is to use this only if needed; or as a learning excercise.
Common
A common (generic) device tree I, suitable for many occasions
- Has 2x UART (plus the console uart), 2x I2C. 1xSPI
- 12 unassigned GPIO pins
Serial
Four UART interfaces and Four I2C interfaces
- Has 4x UART (plus the console uart), 4x I2C
- UART3 has RTC/CTS pins available too
- 10 unassigned GPIO pins
SPI
- Has 3x UART (plus the console uart), 3x I2C. 1xSPI
- 8 unassigned GPIO pins