Re: [PATCH 1/2] dt-bindings: mfd: Add ChromeOS fingerprint binding

From: Krzysztof Kozlowski
Date: Tue Mar 15 2022 - 07:22:31 EST


On 15/03/2022 12:10, Lee Jones wrote:
> On Tue, 15 Mar 2022, Krzysztof Kozlowski wrote:
>
>> On 15/03/2022 00:22, Stephen Boyd wrote:
>>> Add a binding to describe the fingerprint processor found on Chromeboks
>>> 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>
>>> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
>>> ---
>>> .../bindings/mfd/google,cros-ec-fp.yaml | 89 +++++++++++++++++++
>>> 1 file changed, 89 insertions(+)
>>> create mode 100644 Documentation/devicetree/bindings/mfd/google,cros-ec-fp.yaml
>>>
>>> diff --git a/Documentation/devicetree/bindings/mfd/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/mfd/google,cros-ec-fp.yaml
>>> new file mode 100644
>>> index 000000000000..05d2b2b9b713
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/mfd/google,cros-ec-fp.yaml
>>> @@ -0,0 +1,89 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/mfd/google,cros-ec-fp.yaml#
>>
>> Why is this in the MFD directory? Is it really a Multi Function Device?
>> Description is rather opposite. You also did not CC MFD maintainer.
>
> A lot of the ChromeOS Embedded Controller support used to be located
> in MFD. There are still remnants, but most was moved to
> drivers/platform IIRC.
>
> Please see: drivers/mfd/cros_ec_dev.c

Yes, I know, that part is a MFD. But why the fingerprint controller part
is MFD? To me it is closer to input device.

Best regards,
Krzysztof