Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 10 Nov 2022 00:59:44 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Sean Anderson <sean.anderson@seco.com>
Cc:     Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>, netdev@vger.kernel.org,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Jakub Kicinski <kuba@kernel.org>, linux-kernel@vger.kernel.org,
        Andrew Lunn <andrew@lunn.ch>,
        Ioana Ciornei <ioana.ciornei@nxp.com>,
        Madalin Bucur <madalin.bucur@nxp.com>,
        "David S . Miller" <davem@davemloft.net>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Frank Rowand <frowand.list@gmail.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Li Yang <leoyang.li@nxp.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Paul Mackerras <paulus@samba.org>,
        Rob Herring <robh+dt@kernel.org>,
        Saravana Kannan <saravanak@google.com>,
        Shawn Guo <shawnguo@kernel.org>, UNGLinuxDriver@microchip.com,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Vladimir Oltean <vladimir.oltean@nxp.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH net-next v2 00/11] net: pcs: Add support for devices
 probed in the "usual" manner
Message-ID: <20221109225944.n5pisgdytex5s6yk@skbuf>
References: <20221103210650.2325784-1-sean.anderson@seco.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20221103210650.2325784-1-sean.anderson@seco.com>
Precedence: bulk

On Thu, Nov 03, 2022 at 05:06:39PM -0400, Sean Anderson wrote:
> For a long time, PCSs have been tightly coupled with their MACs. For
> this reason, the MAC creates the "phy" or mdio device, and then passes
> it to the PCS to initialize. This has a few disadvantages:
> 
> - Each MAC must re-implement the same steps to look up/create a PCS
> - The PCS cannot use functions tied to device lifetime, such as devm_*.
> - Generally, the PCS does not have easy access to its device tree node

Is there a clear need to solve these disadvantages? There comes extra
runtime complexity with the PCS-as-device scheme (plus the extra
complexity needed to address the DT backwards compatibility problems
it causes; not addressed here).