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Message-ID: <6c53310c-1dc0-6623-369b-1a73fc8f63a5@starfivetech.com>
Date:   Tue, 18 Jul 2023 14:06:01 +0800
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Subject: Re: [PATCH v2 2/3] dt-bindings: spi: constrain minItems of clocks and
 clock-names
To:     Mark Brown <broonie@kernel.org>
CC:     Rob Herring <robh@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        <devicetree@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-riscv@lists.infradead.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        "Emil Renner Berthing" <kernel@esmil.dk>,
        Linus Walleij <linus.walleij@linaro.org>
References: <20230713090015.127541-1-william.qiu@starfivetech.com>
 <20230713090015.127541-3-william.qiu@starfivetech.com>
 <c5ad1e1c-58f4-4833-b9c7-8876c1a0dc27@sirena.org.uk>
 <e3fd0d3f-3fe4-2e23-2548-ecbd487e9c9f@linaro.org>
 <20230713145724.GA3975811-robh@kernel.org>
 <df9de3d8-09da-2b80-b2b4-626cd92fe971@starfivetech.com>
 <9891a7e3-0fce-4d05-8ead-3c0ed155d725@sirena.org.uk>
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From:   William Qiu <william.qiu@starfivetech.com>
In-Reply-To: <9891a7e3-0fce-4d05-8ead-3c0ed155d725@sirena.org.uk>
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On 2023/7/14 19:52, Mark Brown wrote:
> On Fri, Jul 14, 2023 at 03:14:59PM +0800, William Qiu wrote:
>> On 2023/7/13 22:57, Rob Herring wrote:
> 
>> > I suspect that PCLK and SSPCLK are tied to the same clock source. There 
>> > must be an SSPCLK because that is the one used to clock the SPI bus and 
>> > we need to know the frequency of it.
> 
>> After communicating with colleagues in SoC FE, I learned that PCLK and
>> SSPCLK were homologous on JH7110. He said that SSPCLK would divide the
>> frequency internally anyway, and there was no need for external part frequency,
>> so he directly gave them together.
> 
>> So, should I call this clock ssp_apb or keep it SSPCLK?
> 
> I'd expect this to be handled in the DTS for the SoC - connect both
> clocks the binding requires to whatever the upstream clock is, it's not
> clear to me that any binding change is required.

You mean binding two clocks, with the same clock source? Then there is no
need to modify YAML.

Best regards,
William