Re: [PATCH v6 02/13] dt-bindings: mfd: Add bindings for sl28cpld

[Michael Walle]

Am 2020-07-28 10:27, schrieb Lee Jones:
> On Tue, 28 Jul 2020, Michael Walle wrote:
>
> > Am 2020-07-28 09:24, schrieb Lee Jones:
> > > On Sun, 26 Jul 2020, Michael Walle wrote:
> > >
> > > > Add a device tree bindings for the board management controller found
> > > > on
> > > > the Kontron SMARC-sAL28 board.
> > > >
> > > > Signed-off-by: Michael Walle <michael@xxxxxxxx>
> > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> > > > ---
> > > > Changes since v5:
> > > >  - none
> > > >
> > > > Changes since v4:
> > > >  - fix the regex of the unit-address
> > > >
> > > > Changes since v3:
> > > >  - see cover letter
> > > >
> > > >  .../bindings/gpio/kontron,sl28cpld-gpio.yaml  |  54 +++++++
> > > >  .../hwmon/kontron,sl28cpld-hwmon.yaml         |  27 ++++
> > > >  .../kontron,sl28cpld-intc.yaml                |  54 +++++++
> > > >  .../bindings/mfd/kontron,sl28cpld.yaml        | 153
> > > > ++++++++++++++++++
> > > >  .../bindings/pwm/kontron,sl28cpld-pwm.yaml    |  35 ++++
> > > >  .../watchdog/kontron,sl28cpld-wdt.yaml        |  35 ++++
> > > >  6 files changed, 358 insertions(+)
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/gpio/kontron,sl28cpld-gpio.yaml
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/hwmon/kontron,sl28cpld-hwmon.yaml
> > > >  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/kontron,sl28cpld-intc.yaml
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/mfd/kontron,sl28cpld.yaml
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/pwm/kontron,sl28cpld-pwm.yaml
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/watchdog/kontron,sl28cpld-wdt.yaml
> > > >
> > > > diff --git
> > > > a/Documentation/devicetree/bindings/gpio/kontron,sl28cpld-gpio.yaml
> > > > b/Documentation/devicetree/bindings/gpio/kontron,sl28cpld-gpio.yaml
> > > > new file mode 100644
> > > > index 000000000000..9a63a158a796
> > > > --- /dev/null
> > > > +++
> > > > b/Documentation/devicetree/bindings/gpio/kontron,sl28cpld-gpio.yaml
> > > > @@ -0,0 +1,54 @@
> > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > > +%YAML 1.2
> > > > +---
> > > > +$id: http://devicetree.org/schemas/gpio/kontron,sl28cpld-gpio.yaml#
> > > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > > +
> > > > +title: GPIO driver for the sl28cpld board management controller
> > > > +
> > > > +maintainers:
> > > > +  - Michael Walle <michael@xxxxxxxx>
> > > > +
> > > > +description: |
> > > > +  This module is part of the sl28cpld multi-function device. For more
> > > > +  details see
> > > > Documentation/devicetree/bindings/mfd/kontron,sl28cpld.yaml.
> > >
> > > Paths are normally relative.
> >
> > grep Documentation/ Documentation
> >
> > I know there are a lot false positives (esp in the first one)..
> >
> > $ grep -r "\.\./" Documentation | wc -l
> > 1826
> > $ grep -r "Documentation/" Documentation|wc -l
> > 2862
>
> I actually meant just for Device Tree bindings, but it does appear
> that 'Documentation' is used a bunch there too.
>
> My reasons for not liking full paths is that the intention was always
> to move 'Documentation/devicetree' to a new location outside of the
> kernel source tree.

I see. I'll change that.

> > > > +%YAML 1.2
> > > > +---
> > > > +$id: http://devicetree.org/schemas/mfd/kontron,sl28cpld.yaml#
> > > > +$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.
> >
> > > "Board Management Controller (BMC)" ?
> >
> > sounds like IPMI, which I wanted to avoid.
>
> Is there a datasheet?

No there isn't.

> > > > +maintainers:
> > > > +  - Michael Walle <michael@xxxxxxxx>
> > > > +
> > > > +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.

-michael