Re: [PATCH v3 1/2] dt-bindings: input: Add DT bindings for Whiskers switch

[Rob Herring <robh@kernel.org>]

On Tue, Oct 29, 2019 at 2:23 AM Ikjoon Jang <ikjn@chromium.org> wrote:
>
> On Sat, Oct 26, 2019 at 3:41 AM Rob Herring <robh@kernel.org> wrote:
> >
> > On Wed, Oct 23, 2019 at 10:43:48AM +0800, Ikjoon Jang wrote:
> > > Add the DT binding document for Hammer's TABLET_MODE switch.
> >
> > This doesn't have any properties. Why does it need to be in DT? Just
> > have the EC driver instantiate it.
> >
> > >
> > > Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
> > > ---
> > >  .../devicetree/bindings/input/cros-cbas.yaml  | 22 +++++++++++++++++++
> > >  1 file changed, 22 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/input/cros-cbas.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/input/cros-cbas.yaml b/Documentation/devicetree/bindings/input/cros-cbas.yaml
> > > new file mode 100644
> > > index 000000000000..3bc989c6a295
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/input/cros-cbas.yaml
> > > @@ -0,0 +1,22 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> >
> > (GPL-2.0-only OR BSD-2-Clause) for new bindings please.
>
> This will be GPL-2.0-only in next patch.

That's not what I said. Dual licensed please:

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

>
> >
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/input/cros-cbas.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: ChromeOS Hammer's Base Attached Switch
> > > +
> > > +maintainers:
> > > +  - Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > > +
> > > +description:
> > > +  This device is used to signal when a detachable base is attached to a
> > > +  Chrome OS tablet. The node for this device must be under a cros-ec node
> > > +  like google,cros-ec-spi or google,cros-ec-i2c.
> >
> > This should probably just be part of an EC schema where it can be
> > enforced that this is a child node. It could be either embedded into it
> > or referenced. I'd lean toward the former given this is only a
> > compatible string...
>
> Sorry for basic questions here but I'm a bit confused,
> "embedding" means that cros-ec.txt should be converted
> into json schema first and embed this child bindings into there?

Right.

> Many Chrome OS tablets have a switch exposed by 'cros-ec-keyb' device
> which is directly controlled by EC. But this 'cros_cbas' switch device is for
> other types of tablets which need additional logics on EC and HID.
>
> Currently it doesn't need to have other properties, but maybe it could require
> additional properties or device links in the future, plus this device
> is not just
> a EC subdevice, so I'd prefer this to be a separate binding.

But in the description you say it is a child device.

Rob