Re: ARM,SoC: About the use DT-defined properties by 3rd-party drivers
From: Timur Tabi
Date: Mon Sep 12 2016 - 09:24:34 EST
Sebastian Frias wrote:
3rd parties could choose to write a driver (as opposed to use say, a user-mode
library) if it fits their programming model better, if they think they would
have better performance, or other reasons.
The main idea is to make DT the authoritative source of HW description.
Do you really expect the open-source community to make a serious effort
to support out-of-tree drivers written by developers who have no
intention of upstreaming?
There's a process for writing a Linux kernel driver with a DT binding.
That process is not broken.
>Putting smoething together that's only sufficient to support some
>out-of-tree driver with implicit assumptions that we are not aware of is
>far from fantastic.
That does not seem very positive and it is not the case anyway, otherwise we
would not be consulting here:-)
Mark is correct. Trying to create a device tree binding, and getting it
correct 100% the first time, without an actual drivers is just
impossible. To even attempt that is folly.
Agreed, right now this whole thing seems like a really hypothetical question,
Yes, it is.
but the intention is good.
I'm not sure I agree with that.
Actually, I think it would encourage more SoC manufacturers to use DT as a way
to document their HW, which is a good thing.
No it isn't. SOC manufacturers should just release the documentation
they have.
But if I understood correctly your comment, you are basically saying that
without an example is hard to say.
Since the question seems understood, do you have an example of other SoC's
doing something similar?
Similar to what? Every upstream driver today is written the way we're
talking about -- submit the driver with the binding, and both are
reviewed together.
I've seen some big DT descriptions, but it is difficult to know if we are the
first ones trying to use the DT in this way.
Hopefully, you'll be the last.