Re: [PATCH net] net: don't require the hwtstamp NDOs when a PHY provides timestamping

[Kory Maincent]

On 9/18/26 11:55, Nicolai Buchwitz wrote:
> Removing the legacy ioctl fallback made both hwtstamp NDOs mandatory. A
> device that only timestamps in its PHY implements neither, so
> SIOCSHWTSTAMP fails with EOPNOTSUPP before anything looks at the PHY and
> PTP stops working there.
>
> The check only ever picked the legacy path. That path is gone, so drop it
> and test where the NDOs are actually called.
>
> SIOCGHWTSTAMP is new here, not restored. The old path went through
> phy_mii_ioctl(), which only handled SIOCSHWTSTAMP.
>
> Such a device now returns -ENODEV while absent instead of -EOPNOTSUPP,
> like the ones that do implement the NDOs.
>
> Fixes: 5062245a5a7f ("net: remove legacy way to get/set HW timestamp config")
> Signed-off-by: Nicolai Buchwitz <nb@xxxxxxxxxxx>

Reviewed-by: Kory Maincent <kory.maincent@xxxxxxxxxxx>

Thank you!
--
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com