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Message-ID: <5d0980dd11afdd948059bcf9afa2484e5ee97bec.camel@mediatek.com>
Subject: Re: [PATCH v5 4/4] net: stmmac: Update the name of property
 'clk_csr'
From:   Jianguo Zhang <jianguo.zhang@mediatek.com>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        "AngeloGioacchino Del Regno" 
        <angelogioacchino.delregno@collabora.com>,
        "David S . Miller" <davem@davemloft.net>,
        Rob Herring <robh+dt@kernel.org>,
        "Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>
CC:     Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        "Matthias Brugger" <matthias.bgg@gmail.com>,
        Biao Huang <biao.huang@mediatek.com>, <netdev@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-stm32@st-md-mailman.stormreply.com>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-mediatek@lists.infradead.org>
Date:   Tue, 27 Sep 2022 16:43:53 +0800
In-Reply-To: <4f205f0d-420d-8f51-ad26-0c2475c0decd@linaro.org>
References: <20220923052828.16581-1-jianguo.zhang@mediatek.com>
         <20220923052828.16581-5-jianguo.zhang@mediatek.com>
         <e0fa3ddf-575d-9e25-73d8-e0858782b73f@collabora.com>
         <ac24dc0f-0038-5068-3ce6-bbace55c7027@linaro.org>
         <4f205f0d-420d-8f51-ad26-0c2475c0decd@linaro.org>
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Dear Krzysztof,
	Thanks for your comment.

On Fri, 2022-09-23 at 20:15 +0200, Krzysztof Kozlowski wrote:
> On 23/09/2022 20:14, Krzysztof Kozlowski wrote:
> > > This is going to break MT2712e on old devicetrees.
> > > 
> > > The right way of doing that is to check the return value of
> > > of_property_read_u32()
> > > for "snps,clk-csr": if the property is not found, fall back to
> > > the old "clk_csr".
> > 
> > I must admit - I don't care. That's the effect when submitter
> > bypasses
> > DT bindings review (81311c03ab4d ("net: ethernet: stmmac: add
> > management
> > of clk_csr property")).
> > 
> > If anyone wants ABI, please document the properties.
> > 
> > If out-of-tree users complain, please upstream your DTS or do not
> > use
> > undocumented features...
> > 
> 
> OTOH, as Angelo pointed out, handling old and new properties is quite
> easy to achieve, so... :)
> 
So, the conclusion is as following:

1. add new property 'snps,clk-csr' and document it in binding file.
2. parse new property 'snps,clk-csr' firstly, if failed, fall back to
old property 'clk_csr' in driver.

Is my understanding correct?

> Best regards,
> Krzysztof
> 
BRS
Jianguo