RE: [PATCH net-next v2] ethernet/intel: fix PTP_1588_CLOCK dependencies

[Keller, Jacob E]

> -----Original Message-----
> From: Arnd Bergmann <arnd@xxxxxxxxxx>
> Sent: Tuesday, August 03, 2021 11:27 AM
> To: Keller, Jacob E <jacob.e.keller@xxxxxxxxx>
> Cc: Richard Cochran <richardcochran@xxxxxxxxx>; Nicolas Pitre
> <nico@xxxxxxxxxxx>; Brandeburg, Jesse <jesse.brandeburg@xxxxxxxxx>; Nguyen,
> Anthony L <anthony.l.nguyen@xxxxxxxxx>; David S. Miller
> <davem@xxxxxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Arnd Bergmann
> <arnd@xxxxxxxx>; Kurt Kanzenbach <kurt@xxxxxxxxxxxxx>; Saleem, Shiraz
> <shiraz.saleem@xxxxxxxxx>; Ertman, David M <david.m.ertman@xxxxxxxxx>;
> intel-wired-lan@xxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH net-next v2] ethernet/intel: fix PTP_1588_CLOCK
> dependencies
> 
> On Tue, Aug 3, 2021 at 7:19 PM Keller, Jacob E <jacob.e.keller@xxxxxxxxx> wrote:
> > > On Tue, Aug 3, 2021 at 6:14 PM Richard Cochran
> <richardcochran@xxxxxxxxx> wrote:
> 
> > There is an alternative solution to fixing the imply keyword:
> >
> > Make the drivers use it properly by *actually* conditionally enabling the feature
> only when IS_REACHABLE, i.e. fix ice so that it uses IS_REACHABLE instead of
> IS_ENABLED, and so that its stub implementation in ice_ptp.h actually just silently
> does nothing but returns 0 to tell the rest of the driver things are fine.
> 
> I would consider IS_REACHABLE() part of the problem, not the solution, it makes
> things magically build, but then surprises users at runtime when they do not get
> the intended behavior.
> 
>       Arnd

Fair enough. I am also fine with just "depends". We can make most of the drivers simply always enable it, and if a specific driver is used in some embedded setup that has requirements on minimizing things that driver can be setup to use a 2nd config symbol, and all of the other drivers that aren't used can be disabled (as that minimizer is probably already doing!)

I think we've found the best route to go then!

Thanks,
Jake