Re: [PATCH 5/5] dt-bindings: iio: Add adis16475 documentation

[Rob Herring <robh@kernel.org>]

On Tue, Mar 3, 2020 at 3:59 AM Sa, Nuno <Nuno.Sa@analog.com> wrote:
>
> On Tue, 2020-03-03 at 09:43 +0000, Sa, Nuno wrote:
> > [External]
> >
> > On Mon, 2020-03-02 at 16:22 -0600, Rob Herring wrote:
> > > On Tue, Feb 25, 2020 at 01:41:52PM +0100, Nuno Sá wrote:
> > > > Document the ADIS16475 device devicetree bindings.
> > > >
> > > > Signed-off-by: Nuno Sá <nuno.sa@analog.com>
> > > > ---
> > > >  .../bindings/iio/imu/adi,adis16475.yaml       | 130
> > > > ++++++++++++++++++
> > > >  MAINTAINERS                                   |   1 +
> > > >  2 files changed, 131 insertions(+)
> > > >  create mode 100644
> > > > Documentation/devicetree/bindings/iio/imu/adi,adis16475.yaml
> > > >
> > > > diff --git
> > > > a/Documentation/devicetree/bindings/iio/imu/adi,adis16475.yaml
> > > > b/Documentation/devicetree/bindings/iio/imu/adi,adis16475.yaml
> > > > new file mode 100644
> > > > index 000000000000..c0f2146e000c
> > > > --- /dev/null
> > > > +++
> > > > b/Documentation/devicetree/bindings/iio/imu/adi,adis16475.yaml
> > > > @@ -0,0 +1,130 @@
> > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > > +%YAML 1.2
> > > > +---
> > > > +$id: http://devicetree.org/schemas/iio/imu/adi,adis16475.yaml#
> > > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > > +
> > > > +title: Analog Devices ADIS16475 and similar IMUs
> > > > +
> > > > +maintainers:
> > > > +  - Nuno Sá <nuno.sa@analog.com>
> > > > +
> > > > +description: |
> > > > +  Analog Devices ADIS16475 and similar IMUs
> > > > +
> > > > https://www.analog.com/media/en/technical-documentation/data-sheets/ADIS16475.pdf
> > > > +
> > > > +properties:
> > > > +  compatible:
> > > > +    enum:
> > > > +      - adi,adis16475-1
> > > > +      - adi,adis16475-2
> > > > +      - adi,adis16475-3
> > > > +      - adi,adis16477-1
> > > > +      - adi,adis16477-2
> > > > +      - adi,adis16477-3
> > > > +      - adi,adis16470
> > > > +      - adi,adis16465-1
> > > > +      - adi,adis16465-2
> > > > +      - adi,adis16465-3
> > > > +      - adi,adis16467-1
> > > > +      - adi,adis16467-2
> > > > +      - adi,adis16467-3
> > > > +      - adi,adis16500
> > > > +      - adi,adis16505-1
> > > > +      - adi,adis16505-2
> > > > +      - adi,adis16505-3
> > > > +      - adi,adis16507-1
> > > > +      - adi,adis16507-2
> > > > +      - adi,adis16507-3
> > > > +
> > > > +  reg:
> > > > +    maxItems: 1
> > > > +
> > > > +  spi-cpha: true
> > > > +
> > > > +  spi-cpol: true
> > > > +
> > > > +  spi-max-frequency:
> > > > +    maximum: 2000000
> > > > +
> > > > +  interrupts:
> > > > +    maxItems: 1
> > > > +
> > > > +  clocks:
> > > > +    maxItems: 1
> > > > +
> > > > +  clock-names:
> > > > +    oneOf:
> > > > +      - const: sync
> > > > +      - const: direct-sync
> > > > +      - const: pulse-sync
> > > > +      - const: scaled-sync
> > >
> > > According to the datasheet I looked at, the input is called 'sync'.
> > > It
> > > looks like you are mixing operating mode and clock connection.
> >
> > The sync pin is where the external clock should be connected (when
> > available). I'm kinda of using the clock-name property as a way of
> > selecting the mode the user wants to use as done in other devices (
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/iio/imu/adi,adis16480.txt
> > ). In the end, what we should have in the sync pin is an external
> > clock
> > with the exception of the `sync` mode. I guess this one could be
> > called
> > output-sync and, in this case, the sync pin is actually an output pin
> > pulsing when the internal processor collects data.
> >
> > I'm ok in changing it if there's a better way of doing it... Do you
> > have any suggestion?
> >
> > -Nuno Sá
>
> So, you mean having the clock-name only as "sync" (or maybe even
> removing it?) and having a dedicated property like clock-mode?

Yes. Though it needs a vendor prefix: adi,clock-mode. Or perhaps adi,sync-mode?

Rob