Useful Links
One of the problems in using Linux device drivers is finding information about them. A search of the web reveals lots of sources, but many are old and there is a great deal of duplication. Here are useful links on specific topics:
Configuration:
https://www.raspberrypi.org/documentation/configuration/config-txt/README.md
Device Tree
https://www.raspberrypi.org/documentation/configuration/device-tree.md
Overlay Source:
https://github.com/raspberrypi/firmware/tree/master/boot
Overlay Documenation:
https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README
GitHub Pi OS Repository:
https://github.com/raspberrypi/linux
Hardware details:
https://www.raspberrypi.org/documentation/hardware/raspberrypi/datasheets.md
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