Re: [PATCH v2 1/4] spi: dt-bindings: amlogic: spisg: Document A9-specific properties

[Xianwei Zhao]

Hi Mark,
   Thanks for your review.

On 2026/7/30 21:22, Mark Brown wrote:
> Subject:
> Re: [PATCH v2 1/4] spi: dt-bindings: amlogic: spisg: Document 
> A9-specific properties
> From:
> Mark Brown <broonie@xxxxxxxxxx>
> Date:
> 2026/7/30 21:22
>
> To:
> xianwei.zhao@xxxxxxxxxxx
> CC:
> Sunny Luo <sunny.luo@xxxxxxxxxxx>, Rob Herring <robh@xxxxxxxxxx>, 
> Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>, Conor Dooley 
> <conor+dt@xxxxxxxxxx>, linux-amlogic@xxxxxxxxxxxxxxxxxxx, 
> linux-spi@xxxxxxxxxxxxxxx, devicetree@xxxxxxxxxxxxxxx, 
> linux-kernel@xxxxxxxxxxxxxxx
>
>
>
> On Thu, Jul 23, 2026 at 06:43:42AM +0000, Xianwei Zhao via B4 Relay wrote:
> > From: Xianwei Zhao<xianwei.zhao@xxxxxxxxxxx>
> > Document the Amlogic A9 SPISG controller and its additional
> > Device Tree properties.
> > Add the "amlogic,a9-spisg" compatible string and define the
> > A9-specific "amlogic,mo-idle-output" and "amlogic,word-gap"
> > properties, which configure the MOSI idle output level and
> > the inter-word gap, respectively.
> > @@ -35,6 +34,23 @@ properties:
> >     resets:
> >       maxItems: 1
> >   
> > +  amlogic,mo-idle-output:
> > +    description: |
> > +      Controls the MOSI output level when the controller is idle.
> > +      0 - Drive MOSI low
> > +      1 - Drive MOSI high
> > +      2 - Follow the last transmitted bit
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    enum: [0, 1, 2]
> > +    default: 0
> > +
> > +  amlogic,word-gap:
> > +    description: |
> > +      Number of idle clock cycles inserted between consecutive SPI words.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    enum: [0, 1, 2, 3]
> > +    default: 1
> I'd expect these to be per-device properties, not per controller.  The
> word_gap sounds a lot like the existing word_delay feature we have - if
> it's different it'd be good to be clear why.

You're right. There is no functional difference from the existing 
word_delay support. I'll drop this controller-specific DT property and 
handle the hardware word gap through the existing word_delay mechanism 
in the transfer path instead.