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Date:   Mon, 16 Jan 2023 23:04:13 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     "Russell King (Oracle)" <linux@armlinux.org.uk>,
        Marcin Wojtas <mw@semihalf.com>, linux-kernel@vger.kernel.org,
        linux-acpi@vger.kernel.org, netdev@vger.kernel.org,
        rafael@kernel.org, andriy.shevchenko@linux.intel.com,
        sean.wang@mediatek.com, Landen.Chao@mediatek.com,
        linus.walleij@linaro.org, vivien.didelot@gmail.com,
        f.fainelli@gmail.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, hkallweit1@gmail.com,
        jaz@semihalf.com, tn@semihalf.com, Samer.El-Haj-Mahmoud@arm.com
Subject: Re: [net-next: PATCH v4 2/8] net: mdio: switch fixed-link PHYs API
 to fwnode_
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On Mon, Jan 16, 2023 at 08:16:18PM +0200, Vladimir Oltean wrote:
> On Mon, Jan 16, 2023 at 05:50:13PM +0000, Russell King (Oracle) wrote:
> > On Mon, Jan 16, 2023 at 06:34:14PM +0100, Marcin Wojtas wrote:
> > > fixed-link PHYs API is used by DSA and a number of drivers
> > > and was depending on of_. Switch to fwnode_ so to make it
> > > hardware description agnostic and allow to be used in ACPI
> > > world as well.
> > 
> > Would it be better to let the fixed-link PHY die, and have everyone use
> > the more flexible fixed link implementation in phylink?
> 
> Would it be even better if DSA had some driver-level prerequisites to
> impose for ACPI support - like phylink support rather than adjust_link -
> and we would simply branch off to a dsa_shared_port_link_register_acpi()
> function, leaving the current dsa_shared_port_link_register_of() alone,
> with all its workarounds and hacks? I don't believe that carrying all
> that logic over to a common fwnode based API is the proper way forward.

I agree with you there, here is little attempt to make a clean ACPI
binding. Most of the attempts to add ACPI support seem to try to take
the short cut for just search/replace of_ with fwnode_. And we then
have to push back and say no, and generally it then goes quiet.

Marcin, please approach this from the other end. Please document in
Documentation/firmware-guide/acpi/dsd what a clean binding should look
like, and then try to implement it.

      Andrew