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Date:   Sun, 15 Jan 2023 22:56:33 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Pierluigi Passaro <pierluigi.p@variscite.com>
Cc:     wei.fang@nxp.com, shenwei.wang@nxp.com, xiaoning.wang@nxp.com,
        linux-imx@nxp.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, eran.m@variscite.com,
        nate.d@variscite.com, francesco.f@variscite.com,
        pierluigi.passaro@gmail.com
Subject: Re: [PATCH v2] net: fec: manage corner deferred probe condition
Message-ID: <Y8R2kQMwgdgE6Qlp@lunn.ch>
References: <20230115213804.26650-1-pierluigi.p@variscite.com>
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On Sun, Jan 15, 2023 at 10:38:04PM +0100, Pierluigi Passaro wrote:
> For dual fec interfaces, external phys can only be configured by fec0.
> When the function of_mdiobus_register return -EPROBE_DEFER, the driver
> is lately called to manage fec1, which wrongly register its mii_bus as
> fec0_mii_bus.
> When fec0 retry the probe, the previous assignement prevent the MDIO bus
> registration.
> Use a static boolean to trace the orginal MDIO bus deferred probe and
> prevent further registrations until the fec0 registration completed
> succesfully.

The real problem here seems to be that fep->dev_id is not
deterministic. I think a better fix would be to make the mdio bus name
deterministic. Use pdev->id instead of fep->dev_id + 1. That is what
most mdiobus drivers use.

	Andrew