Re: [PATCH] dt-bindings: serial: convert st,asc to DT schema

[Raphaël Gallais-Pou]

Hi Krzysztof,


Le 25/02/2024 à 16:42, Krzysztof Kozlowski a écrit :
> On 25/02/2024 11:03, Raphael Gallais-Pou wrote:
> > Converts st,asc binding to DT schema format and update example.
> >
> > Signed-off-by: Raphael Gallais-Pou <rgallaispou@xxxxxxxxx>
> > ---
> >   .../devicetree/bindings/serial/st,asc.yaml    | 57 +++++++++++++++++++
> >   .../devicetree/bindings/serial/st-asc.txt     | 18 ------
> >   2 files changed, 57 insertions(+), 18 deletions(-)
> >   create mode 100644 Documentation/devicetree/bindings/serial/st,asc.yaml
> >   delete mode 100644 Documentation/devicetree/bindings/serial/st-asc.txt
> >
> > diff --git a/Documentation/devicetree/bindings/serial/st,asc.yaml b/Documentation/devicetree/bindings/serial/st,asc.yaml
> > new file mode 100644
> > index 000000000000..b26e1d247346
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/serial/st,asc.yaml
> > @@ -0,0 +1,57 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/serial/st,asc.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: STMicroelectronics STi SoCs Serial Port
> > +
> > +maintainers:
> > +  - Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
> > +
> > +allOf:
> > +  - $ref: serial.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    const: st,asc
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    maxItems: 1
>
> This wasn't here before and your commit msg does not explain it.

Looking at the device-tree I found that every instance of this device 
refers to a phandle of a clock.

Moreover in the driver of the device, the probe fails if it does not 
find a clock, hence this addition.

cf. drivers/tty/serial/st-asc.c:701
> > +
> > +  uart-has-rtscts: true
>
> Drop, not needed.

Ack
> > +
> > +  st,hw-flow-ctrl:
> > +    description: When set, enable hardware flow control.
> > +    type: boolean
> > +
> > +  st,force-m1:
> > +    description: When set, force asc to be in Mode-1. This is recommended for
> > +      high bit rates above 19.2K.
> > +    type: boolean
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +  - clocks
>
> Also something new.

This is linked to the addition above.

If you agree with this change I will send a v2 explaining this.

Regards,
Raphaël
> Best regards,
> Krzysztof