[PATCH v2 2/3] gpio: mxc: shift gpio_mxc_init() to subsys_initcall level
Linus Walleij
linus.walleij at linaro.org
Mon Sep 12 05:28:27 PDT 2016
On Thu, Sep 8, 2016 at 3:48 AM, Vladimir Zapolskiy
<vladimir_zapolskiy at mentor.com> wrote:
> In general situation on-SoC GPIO controller drivers should be probed
> after pinctrl/pinmux controller driver, because on-SoC GPIOs utilize a
> pin/pad as a resource provided and controlled by pinctrl subsystem.
>
> This is stated in multiple places, e.g. from drivers/Makefile:
>
> GPIO must come after pinctrl as gpios may need to mux pins etc
>
> Looking at Freescale iMX SoC series specifics, imx*_pinctrl_init()
> functions are called at arch_initcall and postcore_initcall init
> levels, so the change of initcall level for gpio-mxc driver from
> postcore_initcall to subsys_initcall level is sufficient. Also note
> that the most of GPIO controller drivers settled at subsys_initcall
> level.
>
> If pinctrl subsystem manages pads with GPIO functions, the change is
> needed to avoid unwanted driver probe deferrals during kernel boot.
>
> Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy at mentor.com>
> ---
> Changes from v1 to v2:
> * replaced by a change with better commit description and which
> moves gpio_mxc_init() call to subsys_initcall() instead of
> apparently too late device_initcall(), this mitigates Shawn's
> expressed concern about the change.
Patch applied with Shawn's ACK.
Yours,
Linus Walleij
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