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

-----Original Message-----
From: Arnd Bergmann <arnd@kernel.org>
Sent: Tuesday, August 03, 2021 11:27 AM
To: Keller, Jacob E <jacob.e.keller@intel.com>
Cc: Richard Cochran <richardcochran@gmail.com>; Nicolas Pitre
[off-list ref]; Brandeburg, Jesse [off-list ref]; Nguyen,
Anthony L [off-list ref]; David S. Miller
[off-list ref]; Jakub Kicinski [off-list ref]; Arnd Bergmann
[off-list ref]; Kurt Kanzenbach [off-list ref]; Saleem, Shiraz
[off-list ref]; Ertman, David M [off-list ref];
intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org; linux-
kernel@vger.kernel.org
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 [off-list ref] wrote:

quoted

quoted

On Tue, Aug 3, 2021 at 6:14 PM Richard Cochran

[off-list ref] wrote:

quoted

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