Re: [PATCH v2 1/3] dt-bindings: chrome: Add ChromeOS fingerprint binding

[Krzysztof Kozlowski]

On 17/03/2022 01:58, Stephen Boyd wrote:
> Add a binding to describe the fingerprint processor found on Chromebooks
> with a fingerprint sensor.
> 
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: <devicetree@xxxxxxxxxxxxxxx>
> Cc: Guenter Roeck <groeck@xxxxxxxxxxxx>
> Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Cc: Craig Hesling <hesling@xxxxxxxxxxxx>
> Cc: Tom Hughes <tomhughes@xxxxxxxxxxxx>
> Cc: Alexandru M Stan <amstan@xxxxxxxxxxxx>
> Cc: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> ---
>  .../bindings/chrome/google,cros-ec-fp.yaml    | 85 +++++++++++++++++++
>  1 file changed, 85 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> 
> diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> new file mode 100644
> index 000000000000..ba4212e6b583
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml

Hm, so chrome starts to be its own subsystem? I see USB connector
bindings are already there, instead of usb directory.

Is there anything special about Chrome that it is equal to subsystem or
architecture? Once second file ends up there, this will encourage more
of such patterns.

> @@ -0,0 +1,85 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/chrome/google,cros-ec-fp.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ChromeOS Embedded Fingerprint Controller
> +
> +description:
> +  Google's ChromeOS embedded fingerprint controller is a device which
> +  implements fingerprint functionality such as unlocking a Chromebook
> +  without typing a password.
> +
> +maintainers:
> +  - Tom Hughes <tomhughes@xxxxxxxxxxxx>
> +
> +properties:
> +  compatible:
> +    const: google,cros-ec-fp
> +
> +  reg:
> +    maxItems: 1
> +
> +  spi-max-frequency:
> +    maximum: 3000000
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  reset-gpios: true
> +  boot0-gpios:
> +    maxItems: 1
> +    description: Assert for bootloader mode.
> +
> +  vdd-supply: true
> +
> +  google,cros-ec-spi-pre-delay:

Use proper unit suffix, so "-us". No need for type then.


> +    description:
> +      This property specifies the delay in usecs between the
> +      assertion of the CS and the first clock pulse.
> +    allOf:

No need for allOf. Just put default/minimum directly.

> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - default: 0
> +      - minimum: 0
> +
> +  google,cros-ec-spi-msg-delay:
> +    description:
> +      This property specifies the delay in usecs between messages.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - default: 0
> +      - minimum: 0

Same here (proper suffix + allOf).



Best regards,
Krzysztof