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

From: Lee Jones
Date: Tue Mar 15 2022 - 07:30:57 EST


On Tue, 15 Mar 2022, Krzysztof Kozlowski wrote:

> 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.

It's tough to say from what I was sent above.

But yes, sounds like it.

We do not want any device 'functionality' in MFD ideally.

--
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog