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Date:   Fri, 12 Aug 2022 12:36:54 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc:     Wei Fang <wei.fang@nxp.com>, "andrew@lunn.ch" <andrew@lunn.ch>,
        "hkallweit1@gmail.com" <hkallweit1@gmail.com>,
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        "kuba@kernel.org" <kuba@kernel.org>,
        "pabeni@redhat.com" <pabeni@redhat.com>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "krzysztof.kozlowski+dt@linaro.org" 
        <krzysztof.kozlowski+dt@linaro.org>,
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Subject: Re: [PATCH net 1/2] dt: ar803x: Document disable-hibernation property
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On Fri, Aug 12, 2022 at 02:25:42PM +0300, Krzysztof Kozlowski wrote:
> hibernation is a feature, but 'disable-hibernation' is not. DTS
> describes the hardware, not policy or driver bejhvior. Why disabling
> hibernation is a property of hardware? How you described, it's not,
> therefore either property is not for DT or it has to be phrased
> correctly to describe the hardware.

However, older DT descriptions need to be compatible with later kernels,
and as existing setups have hibernation enabled, introducing a property
to _enable_ hibernation (which implies if the property is not present,
hibernation is disabled) changes the behaviour with older DT, thereby
breaking backwards compatibility.

Yes, DT needs to describe hardware, but there are also other
constraints too.

-- 
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