Re: [PATCH] pinctrl: samsung: fix missing GPIOLIB on ARM64 Exynos config

From: Arnd Bergmann <arnd@arndb.de>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>,
	Tomasz Figa <tomasz.figa@gmail.com>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	"moderated list:ARM/SAMSUNG EXYNOS ARM ARCHITECTURES" 
	<linux-samsung-soc@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Necip Fazil Yildiran <fazilyildiran@gmail.com>,
	"# 3.4.x" <stable@vger.kernel.org>
Subject: Re: [PATCH] pinctrl: samsung: fix missing GPIOLIB on ARM64 Exynos config
Date: Wed, 20 Apr 2022 14:10:03 +0200	[thread overview]
Message-ID: <CAK8P3a0uH5KjaobrqUmJQnvMmjkUaR1iC-7jEPjZFjZF1Z-GfQ@mail.gmail.com> (raw)
In-Reply-To: <20220420115512.175917-1-krzysztof.kozlowski@linaro.org>

On Wed, Apr 20, 2022 at 1:55 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> The Samsung pinctrl drivers depend on OF_GPIO, which is part of GPIOLIB.
> ARMv7 Exynos platform selects GPIOLIB and Samsung pinctrl drivers. ARMv8
> Exynos selects only the latter leading to possible wrong configuration
> on ARMv8 build:
>
>   WARNING: unmet direct dependencies detected for PINCTRL_EXYNOS
>     Depends on [n]: PINCTRL [=y] && OF_GPIO [=n] && (ARCH_EXYNOS [=y] || ARCH_S5PV210 || COMPILE_TEST [=y])
>     Selected by [y]:
>     - ARCH_EXYNOS [=y]
>
> Reported-by: Necip Fazil Yildiran <fazilyildiran@gmail.com>
> Fixes: eed6b3eb20b9 ("arm64: Split out platform options to separate Kconfig")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>

This does not look like a correct fix:

> diff --git a/drivers/pinctrl/samsung/Kconfig b/drivers/pinctrl/samsung/Kconfig
> index dfd805e76862..c852fd1dd284 100644
> --- a/drivers/pinctrl/samsung/Kconfig
> +++ b/drivers/pinctrl/samsung/Kconfig
> @@ -4,13 +4,13 @@
>  #
>  config PINCTRL_SAMSUNG
>         bool
> -       depends on OF_GPIO
> +       select GPIOLIB
> +       select OF_GPIO
>         select PINMUX
>         select PINCONF

OF_GPIO is an automatic symbol that is always enabled when both
GPIOLIB and OF are enabled. Selecting it from somewhere else cannot
really work at all. I see we have a few other instances and should probably
fix those as well.

>  config PINCTRL_EXYNOS
>         bool "Pinctrl common driver part for Samsung Exynos SoCs"
> -       depends on OF_GPIO
>         depends on ARCH_EXYNOS || ARCH_S5PV210 || COMPILE_TEST
>         select PINCTRL_SAMSUNG
>         select PINCTRL_EXYNOS_ARM if ARM && (ARCH_EXYNOS || ARCH_S5PV210)

The problem here is that PINCTRL_EXYNOS and the others can be built for
compile-testing without CONFIG_OF on non-arm machines.

I think the correct dependency line would be

      depends on ARCH_EXYNOS || ARCH_S5PV210 || (COMPILE_TEST && OF)

which guarantees that OF_GPIO is also enabled.

    Arnd