Re: [PATCH v1 1/3] gpio: defer probe if pinctrl cannot be found

[Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>]

Hi Tomeu,

On Wed, Jul 1, 2015 at 2:45 PM, Tomeu Vizoso <tomeu.vizoso-ZGY8ohtN/8qB+jHODAdFcQ@public.gmane.org> wrote:
> When an OF node has a pin range for its GPIOs, return -EPROBE_DEFER if
> the pin controller isn't available.
>
> Otherwise, the GPIO range wouldn't be set at all unless the pin
> controller probed always before the GPIO chip.
>
> With this change, the probe of the GPIO chip will be deferred and will
> be retried at a later point, hopefully once the pin controller has been
> registered and probed already.
>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso-ZGY8ohtN/8qB+jHODAdFcQ@public.gmane.org>

I was a bit afraid this would break the case of gpio controllers that are
also pin controllers, i.e. where "gpio-ranges" points to the gpio controller
itself[*], but it doesn't.

Tested-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>

[*] E.g. "[PATCH 2/7] ARM: shmobile: r8a7740 dtsi: Add missing "gpio-ranges"
    to gpio node" (http://www.spinics.net/lists/linux-sh/msg43077.html)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.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