On Wed, Dec 1, 2021 at 11:42 AM Thierry Reding <thierry.reding@xxxxxxxxx> wrote:
>
> On Mon, Nov 29, 2021 at 07:44:32PM -0600, Rob Herring wrote:
> > On Fri, Nov 19, 2021 at 03:38:36PM +0100, Thierry Reding wrote:
> > > From: Thierry Reding <treding@xxxxxxxxxx>
> > >
> > > Convert the NVIDIA Tegra186 (and later) BPMP I2C bindings from the
> > > free-form text format to json-schema.
> > >
> > > Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
> > > ---
> > > Changes in v2:
> > > - add missing additionalProperties: false
> > >
> > > .../bindings/i2c/nvidia,tegra186-bpmp-i2c.txt | 42 -------------------
> > > .../i2c/nvidia,tegra186-bpmp-i2c.yaml | 42 +++++++++++++++++++
> > > 2 files changed, 42 insertions(+), 42 deletions(-)
> > > delete mode 100644 Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.txt
> > > create mode 100644 Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.txt b/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.txt
> > > deleted file mode 100644
> > > index ab240e10debc..000000000000
> > > --- a/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.txt
> > > +++ /dev/null
> > > @@ -1,42 +0,0 @@
> > > -NVIDIA Tegra186 BPMP I2C controller
> > > -
> > > -In Tegra186, the BPMP (Boot and Power Management Processor) owns certain HW
> > > -devices, such as the I2C controller for the power management I2C bus. Software
> > > -running on other CPUs must perform IPC to the BPMP in order to execute
> > > -transactions on that I2C bus. This binding describes an I2C bus that is
> > > -accessed in such a fashion.
> > > -
> > > -The BPMP I2C node must be located directly inside the main BPMP node. See
> > > -../firmware/nvidia,tegra186-bpmp.txt for details of the BPMP binding.
> > > -
> > > -This node represents an I2C controller. See ../i2c/i2c.txt for details of the
> > > -core I2C binding.
> > > -
> > > -Required properties:
> > > -- compatible:
> > > - Array of strings.
> > > - One of:
> > > - - "nvidia,tegra186-bpmp-i2c".
> > > -- #address-cells: Address cells for I2C device address.
> > > - Single-cell integer.
> > > - Must be <1>.
> > > -- #size-cells:
> > > - Single-cell integer.
> > > - Must be <0>.
> > > -- nvidia,bpmp-bus-id:
> > > - Single-cell integer.
> > > - Indicates the I2C bus number this DT node represent, as defined by the
> > > - BPMP firmware.
> > > -
> > > -Example:
> > > -
> > > -bpmp {
> > > - ...
> > > -
> > > - i2c {
> > > - compatible = "nvidia,tegra186-bpmp-i2c";
> > > - #address-cells = <1>;
> > > - #size-cells = <0>;
> > > - nvidia,bpmp-bus-id = <5>;
> > > - };
> > > -};
> > > diff --git a/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.yaml b/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.yaml
> > > new file mode 100644
> > > index 000000000000..351e12124959
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/i2c/nvidia,tegra186-bpmp-i2c.yaml
> > > @@ -0,0 +1,42 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/i2c/nvidia,tegra186-bpmp-i2c.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: NVIDIA Tegra186 (and later) BPMP I2C controller
> > > +
> > > +maintainers:
> > > + - Thierry Reding <thierry.reding@xxxxxxxxx>
> > > + - Jon Hunter <jonathanh@xxxxxxxxxx>
> > > +
> > > +description: |
> > > + In Tegra186 and later, the BPMP (Boot and Power Management Processor)
> > > + owns certain HW devices, such as the I2C controller for the power
> > > + management I2C bus. Software running on other CPUs must perform IPC to
> > > + the BPMP in order to execute transactions on that I2C bus. This
> > > + binding describes an I2C bus that is accessed in such a fashion.
> > > +
> > > + The BPMP I2C node must be located directly inside the main BPMP node.
> > > + See ../firmware/nvidia,tegra186-bpmp.yaml for details of the BPMP
> > > + binding.
> > > +
> > > + This node represents an I2C controller. See ../i2c/i2c.txt for details
> > > + of the core I2C binding.
> > > +
> > > +properties:
> > > + compatible:
> > > + const: nvidia,tegra186-bpmp-i2c
> > > +
> >
> > > + "#address-cells":
> > > + const: 1
> > > +
> > > + "#size-cells":
> > > + const: 0
> >
> > Covered by i2c-controller.yaml. Add a reference and then use
> > unevaluatedProperties.
>
> About that: I've recently noticed that this doesn't seem to work
> properly. I'm using branch draft2020-12 from your github and my
Use dtschema main/master branch. That branch is likely stale.
> understanding was that this should give us support for
> unevaluatedProperties. And indeed, it no longer complains about
> #address-cells and #size-cells if I remove them from this binding,
> presumably because it gets them from i2c-controller.yaml.
>
> However, a side-effect seems to be that now it also ignores any
> properties that aren't defined anywhere. So for example if I touch
> up the example in firmware/nvidia,tegra186-bpmp.yaml and add a bogus
> "foo-bar = <0>;" property in the BPMP I2C node, then it'll blindly
> accept that as valid.
Do you have unevaluatedProperties within the i2c node? It only applies
to 1 level, and you can't have a parent+child schema evaluated with
another child (or parent+child) schema. This is why the graph schema
is done the way it is and why we're splitting spi-controller.yaml
child node schema out to spi-peripheral.yaml.
> The validation will flag if I set #address-cells = <2> in the BPMP
> I2C node, so validation of the schema still seems to work, but for
> some reason it won't flag any properties that haven't been specified
> in the schema.
>
> Do I misunderstand how this is supposed to work, or is there something
> wrong with the current implementation of unevaluatedProperties?
>
> Thierry
