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Date:   Tue, 05 Apr 2022 10:48:21 +0200
From:   Michael Walle <michael@walle.cc>
To:     Richard Cochran <richardcochran@gmail.com>
Cc:     Andrew Lunn <andrew@lunn.ch>, davem@davemloft.net,
        grygorii.strashko@ti.com, kuba@kernel.org, kurt@linutronix.de,
        linux-kernel@vger.kernel.org, linux@armlinux.org.uk,
        mlichvar@redhat.com, netdev@vger.kernel.org,
        qiangqing.zhang@nxp.com, vladimir.oltean@nxp.com,
        Horatiu Vultur <horatiu.vultur@microchip.com>
Subject: Re: [PATCH RFC V1 net-next 3/4] net: Let the active time stamping
 layer be selectable.
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Am 2022-04-05 07:59, schrieb Richard Cochran:
> On Mon, Apr 04, 2022 at 07:12:11PM +0200, Michael Walle wrote:
> 
>> That would make sense. I guess what bothers me with the current
>> mechanism is that a feature addition to the PHY in the *future* (the
>> timestamping support) might break a board - or at least changes the
>> behavior by suddenly using PHY timestamping.
> 
> That is a good point, but then something will break in any case.

Can the ethernet driver select the default one? So any current
driver which has "if phy_has_hwtstamp() forward_ioctl;" can set
it to PHY while newer drivers can (or should actually) leave it as
MAC.

This doesn't really fix the problem per se. But at least new
drivers won't be affected. For my problem at hand, I'd need to
convince Microchip to default to MAC although the driver is
already in the tree (but there is no user of it in mainline
right now).

-michael