Date:   Mon, 6 Mar 2023 09:55:15 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     "Russell King (Oracle)" <linux@armlinux.org.uk>,
        =?UTF-8?B?S8O2cnk=?= Maincent <kory.maincent@bootlin.com>,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        linux-omap@vger.kernel.org, Michael Walle <michael@walle.cc>,
        Richard Cochran <richardcochran@gmail.com>,
        thomas.petazzoni@bootlin.com, Jay Vosburgh <j.vosburgh@gmail.com>,
        Veaceslav Falico <vfalico@gmail.com>,
        Andy Gospodarek <andy@greyhouse.net>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Joakim Zhang <qiangqing.zhang@nxp.com>,
        Vladimir Oltean <vladimir.oltean@nxp.com>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        UNGLinuxDriver@microchip.com,
        Grygorii Strashko <grygorii.strashko@ti.com>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Minghao Chi <chi.minghao@zte.com.cn>,
        Jie Wang <wangjie125@huawei.com>,
        Guangbin Huang <huangguangbin2@huawei.com>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>,
        Wang Yufen <wangyufen@huawei.com>,
        Alexandru Tachici <alexandru.tachici@analog.com>,
        Oleksij Rempel <linux@rempel-privat.de>
Subject: Re: [PATCH v2 3/4] net: Let the active time stamping layer be
 selectable.
Message-ID: <20230306095515.20e819d1@kernel.org>
In-Reply-To: <94544cd0-18da-40d1-8691-66e50d42bfb4@lunn.ch>
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        <20230303164248.499286-4-kory.maincent@bootlin.com>
        <011d63c3-e3ff-4b67-8ab7-d39f541c7b31@lunn.ch>
        <ZANu37JHCKwsiCTT@shell.armlinux.org.uk>
        <94544cd0-18da-40d1-8691-66e50d42bfb4@lunn.ch>
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On Sat, 4 Mar 2023 20:46:05 +0100 Andrew Lunn wrote:
> > Since the ioctl is to do with requesting what we want the timestamping
> > layer to be doing with packets, putting it in ptp_clock_info makes
> > very little sense.  
> 
> So there does not appear to be an object to represent a time stamper?
> 
> Should one be added? It looks like it needs two ops hwtstamp_set() and
> hwtstamp_get(). It would then be registered with the ptp core. And
> then the rest of what i said would apply...

IMHO time stamper is very much part of the netdev. I attribute the lack
of clarity palatially to the fact that (for reasons unknown) we still
lug the request as a raw IOCTL/ifreq. Rather than converting it to an
NDO/phydev op in the core.. Also can't think of a reason why modeling
it as a separate object would be useful?