Re: [PATCH] of/irq: provide int of_irq_parse_and_map_pci wrapper

Hi Arnd,

On Fri, May 9, 2014 at 10:45 AM, Arnd Bergmann [off-list ref] wrote:

On Friday 09 May 2014 10:28:39 Lucas Stach wrote:

quoted

Am Freitag, den 09.05.2014, 08:58 +0200 schrieb Arnd Bergmann:

quoted

The pci-rcar driver is enabled for compile tests, and this has
now shown that the driver cannot build without CONFIG_OF,
following the inclusion of f8f2fe7355fb "PCI: rcar: Use new OF
interrupt mapping when possible":

drivers/built-in.o: In function `rcar_pci_map_irq':
:(.text+0x1cc7c): undefined reference to `of_irq_parse_and_map_pci'

As pointed out by Ben Dooks and Geert Uytterhoeven, this is actually
supposed to build fine, which we can achieve if we make the
declaration of of_irq_parse_and_map_pci conditional on CONFIG_OF
and provide an empty inline function otherwise, as we do for
a lot of other of interfaces.

This lets us build the rcar_pci driver again without CONFIG_OF,
which won't work but give us compile time coverage.

This part of the commit message is confusing. The driver is explicitly
written to fall back to a platform irq when OF interrupt mapping doesn't
work (return 0 or error), to keep non DT enabled boards working.

I hadn't thought of the compile time dependency, so thanks for fixing
this up.

I thought it was meant to keep old DTBs working. AFAIK, there is no
legacy board file support for rcar-gen2, so we don't actually have to
worry about that.

arch/arm/mach-shmobile/board-lager.c does intantiate platform devices
for it, and I guess they're still to be added to .../board-koelsch.c.

However, all legacy board configs in arch/arm/mach-shmobile/Kconfig
do "select USE_OF", so the file will always be build with OF=y.

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