On Tue, 28 Jul 2020, Michael Walle wrote:

Am 2020-07-28 10:56, schrieb Lee Jones:

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+$id: http://devicetree.org/schemas/mfd/kontron,sl28cpld.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Kontron's sl28cpld board management controller

"S128CPLD" ?

still not, its sl28cpld, think of a project/code name, not the product
appended with CPLD.

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"Board Management Controller (BMC)" ?

sounds like IPMI, which I wanted to avoid.

Is there a datasheet?

No there isn't.

Then what are you working from?

Ok, there is no public datasheet. If that wasn't clear before, I'm working
for that company that also implemented that CPLD.

No, that wasn't clear.  You said there was no datasheet.

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+maintainers:
+  - Michael Walle [off-list ref]
+
+description: |
+  The board management controller may contain different IP blocks
like
+  watchdog, fan monitoring, PWM controller, interrupt controller
and a
+  GPIO controller.
+
+properties:
+  compatible:
+    const: kontron,sl28cpld-r1

We don't usually code revision numbers in compatible strings.

Is there any way to pull this from the H/W?

No, unfortunately you can't. And I really want to keep that, in case
in the future there are some backwards incompatible changes.

Rob,

I know you reviewed this already, but you can give your opinion on
this specifically please?  I know that we have pushed back on this in
the past.

Oh, come one. That is an arbitrary string. "sl28cpld-r1" is the first
implementation of this. A future "sl28cpld-r2" might look completely
different and might not suite the simple MFD at all. "sl28cpld" is
a made up name - as "sl28cpld-r1" is, too.

Well that sounds bogus for a start.  I guess that's one of the
problems with trying to support programmable H/W in S/W.

What sounds bogus? That we name the implementation sl28cpld?
How is that different to like adt7411? Its just a name made up by
the vendor. So if there is a new version of the adt7411 the vendor 
might name it adt7412.

Using an arbitrary string as a compatible would be bogus.

So here 'sl28cpld' is the device name, so it's not actually
arbitrary.  That's a good start.

We name it sl28cpld-r2. So what is the problem here?

Do you though?  So 'sl28cpld-r1' is the name of the device?  The name
that is quoted from the (private) datasheet?  Because looking at the
implementation and going by the conversation, it sounds as though
you-re only adding the '-r1' piece to the compatible string for
revision identification.  Which if true, is not usually allowed and
warrants intervention by Rob.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog

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