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Date:   Fri, 12 Aug 2022 13:30:45 +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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        "edumazet@google.com" <edumazet@google.com>,
        "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 03:04:41PM +0300, Krzysztof Kozlowski wrote:
> I did not propose a property to enable hibernation. The property must
> describe hardware, so this piece is missing, regardless whether the
> logic in the driver is "enable" or "disable".
> 
> The hardware property for example is: "broken foo, so hibernation should
> be disabled" or "engineer forgot to wire cables, so hibernation won't
> work"...

From the problem description, the PHY itself isn't broken. The stmmac
hardware doesn't reset properly when the clock from the PHY is stopped.
That could hardly be described as "broken" - it's quite common for
hardware specifications to state that clocks must be running for the
hardware to operate correctly.

This is a matter of configuring the hardware to inter-operate correctly.
Isn't that the whole purpose of DT?

So, nothing is broken. Nothing has forgotten to be wired. It's a matter
of properly configuring the hardware. Just the same as selecting the
correct interface mode to connect two devices together.

-- 
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