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Cubieboard 6 - device tree

Started by ssdev, August 26, 2017, 10:44:55 pm

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ssdev

Hi All,

I'm struggling with the learning curve for CB6/device tree.

We have an application and are replacing CB2 boards. I'm trying to maintain pin-compatibility, so either out last CB2 stock or CB6 can be plugged into the same baseboard.

What I'm after is a straightforward explanation -- or links to some concrete advice -- on how to change pin assignments.
The FEX file was pretty understandable.
I understand the purpose of the device tree, etc, also.
But, I can't join the dots so easily...

Specifically, we want to use a few pins as GPIO with interrupts, and 1-wire.
How do I make the assignment of, say, "this header pin = gpio X in userspace"?
The S500/new board also seems a little more restricted than the A20 in terms of which pins can be assigned to which tasks...?