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

[Xianwei Zhao <xianwei.zhao@amlogic.com>]

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@kernel.org>
> Date:
> 2026/7/30 21:22
> 
> To:
> xianwei.zhao@amlogic.com
> CC:
> Sunny Luo <sunny.luo@amlogic.com>, Rob Herring <robh@kernel.org>, 
> Krzysztof Kozlowski <krzk+dt@kernel.org>, Conor Dooley 
> <conor+dt@kernel.org>, linux-amlogic@lists.infradead.org, 
> linux-spi@vger.kernel.org, devicetree@vger.kernel.org, 
> linux-kernel@vger.kernel.org
> 
> 
> 
> On Thu, Jul 23, 2026 at 06:43:42AM +0000, Xianwei Zhao via B4 Relay wrote:
>> From: Xianwei Zhao<xianwei.zhao@amlogic.com>
>> 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.


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