Which document I can refer to understand the Hikey Pin Control definitions in device tree?

Which document can I refer to understand the Pin Control definitions in the device tree : https://elixir.bootlin.com/linux/latest/source/arch/arm64/boot/dts/hisilicon/hikey-pinctrl.dtsi for LeMaker Hikey 620?

Is there SoC document available on which these definitions are based?
I am new to device tree (know how device tree works at basic level) and hence trying to understand the pin control definitions by reading the device tree files for Hikey 620. I was curious on what data/document are these definitons based on?

Yeah, the pin control DT binding is not easy to understand for me as well :slight_smile: Usually, I will go back to read the doc: https://elixir.bootlin.com/linux/v5.2.2/source/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt

I think he means the specific values for hikey itself.

yes. I mean the specific values. Sorry in case was not clear.

I am looking for a document which defines all the pin details of the Kirin 620 SoC as well as the bus layout on the Hikey board (which peripherals sit on which bus - APB? AHB? etc) .

Can someone please share the respective document which covers these details? The documents posted on the github page for Hikey 620 are very top-level and do not share these details.

@insanecoder AFAIK there is no such document exist. I usually refer devicetree and schematics.

But someone must be writing the device tree as well. At least that person will have access to that info. Is there a specific reason why this information not made public ? (I mean its already public in the form of device tree but no dedicated document was prepared for this information) - Just a curious question.

The answer is simpler than you would ever guess: Its because lawmakers, intellectual property law, and lawyers are retarded.

And there is also something about corporate types… they’re under some crazy delusion that keeping information about their products SECRET will be more profitable than making it possible for people to ACTUALLY USE their products. I wish somebody would explain it to them that I WILL NOT BUY SOMETHING THAT I CANNOT USE.

Seriously. I didn’t expect this reason. Absence of such documents seriously makes the devices un-usable (at least) for certain category of developers.

Well unfortunately, your alternative may be NDA’s.