Date:   Fri, 17 Mar 2023 17:37:33 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     =?iso-8859-1?Q?=C1lvaro_Fern=E1ndez?= Rojas <noltari@gmail.com>
Cc:     Vladimir Oltean <olteanv@gmail.com>, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        f.fainelli@gmail.com, jonas.gorski@gmail.com, hkallweit1@gmail.com,
        linux@armlinux.org.uk, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] net: dsa: b53: mmap: register MDIO Mux bus controller
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On Fri, Mar 17, 2023 at 05:30:38PM +0100, ?lvaro Fern?ndez Rojas wrote:
> El vie, 17 mar 2023 a las 17:27, Andrew Lunn (<andrew@lunn.ch>) escribi?:
> >
> > > > The proposed solution is too radical for a problem that was not properly
> > > > characterized yet, so this patch set has my temporary NACK.
> > >
> > > Forgive me, but why do you consider this solution too radical?
> >
> > I have to agree with Vladimir here. The problem is not the driver, but
> > when the driver is instantiated. It seems radical to remove a driver
> > just because it loads at the wrong time. Ideally you want the driver
> > to figure out now is not a good time and return -EPROBE_DEFER, because
> > a resource it requires it not available.
> 
> Ok, I'm open to suggestions.
> Any ideas on how exactly to figure out when it's a good time to probe
> or return -EPROBE_DEFER instead?

Vladimir already said:

> > > We need to know what resource belonging to the switch is it that the
> > > MDIO mux needs.

Please answer that question. Once we know what the resource is, we can
look at how to export it to the mux in a way that is safe.

       Andrew