Hi Linus,
On 2017-03-28 11:46, Linus Walleij wrote:
On Thu, Mar 23, 2017 at 5:02 PM, jacopo <jacopo@xxxxxxxxxx> wrote:
> + Required properties:
> + - renesas,pins
Just "pins"?
You know, I've been thinking about this, bu the "pins" property
definition in pinctrl-bidings is the following one:
Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
---
- pins takes a list of pin names or IDs as a required argument. The
specific binding for the hardware defines:
- Whether the entries are integers or strings, and their
meaning.
---
And all examples there assume one "pin name" or "ID" per pin.
Now, we use 2 values per each pin (the pin ID and the alternate
function number), so to me this is different from what the generic
binding describes.
Also, pinctrl-single, and pinctrl-imx which have and ABI similar to
the one this driver define, use "pinctrl-single,pins" and "fsl,pins"
respectively as property names.
So either they have to be updated yet, or we should keep using
"renesas,pins" for our own defined ABI.
Maybe Linus or other pinctrl people can give some suggestion here.
To me as subsystem maintainer any "necessarily different" bindings
are just a big confusion for the head.
Understandable :)
Since you're adding a new driver, try to stick to the generic bindings
even if it deviates from what you are used to for Renesas, because
even if it may be more work for you guys or make you annoyed that
now a certain Renesas is different from all other Renesas platforms,
for the community this makes things easier to maintain because
we can look at the driver and its bindings and say "ah I know this".
The fact that historically all the early adopters of pinctrl in device
tree
have these funky custom bindings is unfortunate but just something
that we need to live with.
To avoid any confusion, please bear with me and clarify this once and
for all,
since I'm not certain I fully got you here.
Are you suggesting:
1) Use "pins" property with the currently implemented ABI (which
slightly differs
from the standard documented one as explained above. Not sure it is
fine overriding
it or not)
2) Use "pins" property and change our ABI to match the documented one:
one ID (integer
or string) per pin, not 2 as we're doing now.
Both solutions are easily implementable; 2) requires some more work to
make pin id, function number
and pin configuration fit in one single integer, but is achievable for
sure.
Thanks
j
Yours,
Linus Walleij
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