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

From: Geert Uytterhoeven
Date: Thu Jul 02 2015 - 04:49:50 EST


Hi Tomeu,

On Wed, Jul 1, 2015 at 2:45 PM, Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx>

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@xxxxxxxxx>

[*] 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@xxxxxxxxxxxxxx

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
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