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Date:   Tue, 8 Aug 2023 19:38:06 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     Andrew Lunn <andrew@lunn.ch>, Andrew Halaney <ahalaney@redhat.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alex Elder <elder@linaro.org>,
        Srini Kandagatla <srinivas.kandagatla@linaro.org>,
        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,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Subject: Re: [PATCH 0/2] net: stmmac: allow sharing MDIO lines
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On Tue, Aug 08, 2023 at 08:26:22PM +0200, Bartosz Golaszewski wrote:
> When I say "device unbind", I don't just mean manual unbinding using
> sysfs. I mean any code path (rmmod, unplugging the USB, etc.) that
> leads to the device being detached from its driver. This is a
> perfectly normal situation and should work correctly.
> 
> I won't be fixing it for this series but may end up looking into
> establishing some kind of device links between MACs and their "remote"
> PHYs that would allow to safely unbind them.

I don't think you're the first to suggest that!

That gets difficult - because although the PHY may be a different
driver, the MDIO bus may be provided by the _same_ hardware as the
ethernet MAC itself. So you end up with a circular dependency - the
PHY device depends on the MDIO bus device (which is the ethernet MAC)
and then you make the ethernet MAC depend on the PHY device.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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