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Date: Thu, 9 Feb 2017 18:20:24 +0100
From: Andrew Lunn <andrew@lunn.ch>
To: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org,
        "David S . Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        Jason Cooper <jason@lakedaemon.net>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        Gregory Clement <gregory.clement@free-electrons.com>,
        Russell King <linux@armlinux.org.uk>,
        Florian Fainelli <f.fainelli@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] [net-next] ARM: orion: fix PHYLIB dependency
Message-ID: <20170209172024.GE29882@lunn.ch>
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> Adding a 'select' statement to something as broad as NETDEVICES sounds
> really bad, it has a significant risk of introducing dependency loops
> and may be confusing if you want to build a multiplatform config without
> networking support (note that NETDEVICES in turn depends on NET, which
> can also be disabled).

O.K, so overall it is not simple. So lets drop my idea.
 
> One possibility would be to have a special Kconfig symbol that controls
> mdiobus_register_board_info() being present and have that symbol
> force PHYLIB to never be "=m". Then we can either have no networking
> support and no phylib, turning mdiobus_register_board_info() into a
> stub, or we have the function built-in and reachable from the board
> code.

FYI: Florian is working on splitting MDIO out of PHYLIB. There will be
two separate symbols, so it will be possible to have MDIO without
PHYLIB. When this happens, i expect mdiobus_register_board_info() will
be in the MDIO part, not PHYLIB.

   Andrew