Re: [PATCH] net: usb: lan78xx: add weak dependency with micrel phy module

[Dragan Simic <dsimic@manjaro.org>]

On 2024-07-28 21:45, Andrew Lunn wrote:
>> Basically, the way I see it, weakdeps are the right solution for the
>> problem at hand, i.e. for the generation of the initial ramdisk with
>> all the possible PHY driver modules.
> 
> Sorry, but i still don't see how this works.
> 
> Say you get this one patch merged. What then? You throw all other PHY
> drivers which don't have a weakdep out of the initramfs? That
> potentially breaks around 200 MAC drivers who need those PHYs you have
> discarded.

Actually, no PHY drivers can be thrown out of an initial ramdisk by this
patch, [1] simply because no PHY drivers not needed for a specific 
system
shouldn't be included there before, unless they were added specifically
by the utilities that created the initial ramdisk, but that's beyond the
dependencies that the kernel provides in /lib/modules, and beyond what
can be obtained by automatic detection using /sys/devices on a 
particular
system.  That's all a result of this specific module dependency being
unknown before, at the kernel level.

In other words, this patch doesn't subtract anything.  Instead, it just
adds a weakdep link between the lan78xx and micrel modules, so the 
kernel
itself can report that dependency, which may actually result in one more
PHY driver added to a generated initial ramdisk.

[1] 
https://lore.kernel.org/netdev/20240724102349.430078-1-jtornosm@redhat.com/