On Sat, Jun 30, 2012 at 9:20 PM, Arnd Bergmann [off-list ref] wrote:

On Saturday 30 June 2012, Thierry Reding wrote:

quoted

I hadn't thought about the allyesconfig case yet. Adding a "depends on
!HAVE_PWM" to the PWM symbol should work and is the easiest fix to this
kind of problem while other PWM legacy API implementations are ported to
the PWM subsystem.

Sascha, Arnd (Cc'ed): what do you think?

I don't know if I'll get enough time to test this over the weekend but I
should get to it when I'm back in the office on Monday.

You cannot depend on a symbol in the same place that provides it -- that
would be a recursive dependency (or a paradox).

I think that all the drivers that are not converted to the common PWM
layer yet should depend on not enabling the common code. Once they
are all moved over, that dependency will go away.

Hence you cannot have a single kernel image that contains both legacy and new
drivers. I don't know whether there's any such combination that makes sense,
though.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds