Re: [PATCH RFC V1 net-next 3/4] net: Let the active time stamping layer be selectable.

From: Grygorii Strashko
Date: Wed Apr 06 2022 - 09:48:44 EST

On 05/04/2022 18:48, Richard Cochran wrote:
On Tue, Apr 05, 2022 at 03:29:05PM +0200, Andrew Lunn wrote:

Maybe. Device tree is supposed to describe the hardware, not how you
configure the hardware. Which PTP you using is a configuration choice,
so i expect some people will argue it should not be in DT.


Pure DT means no configuration choices.

(but you find many examples that break the rules!)

My point was related to one of issues described by Michael Walle in this thread:
- supporting TS by the PHY may require also additional board support;
- phy_has_hwtstamp() defined statically by PHY drivers without taking into account board design;
- Kconfig option Doesn't really work with generic distro support and not allowed per-port cfg.

So adding smth like "hwtstamp-en" will clear identify that this particular PHY on this particular board
supports time stamping.
(or hwtstamp-full/hwtstamp-rx/hwtstamp-tx).

Of course, it will not help with default or dynamic selection of time stamping layer :(,
but it will be one problem less.

Best regards,
Grygorii, Ukraine