Re: [PATCH 5/7] ARM: samsung: Kill useless HAVE_S3C2410_WATCHDOG

From: Guenter Roeck <linux@roeck-us.net>
To: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>,
	Kukjin Kim <kgene@kernel.org>,
	Vincent Sanders <vince@simtec.co.uk>,
	Simtec Linux Team <linux@simtec.co.uk>,
	Kyungmin Park <kyungmin.park@samsung.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Tomasz Figa <tomasz.figa@gmail.com>,
	Chanwoo Choi <cw00.choi@samsung.com>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	Wim Van Sebroeck <wim@linux-watchdog.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Linus Walleij <linus.walleij@linaro.org>,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-samsung-soc@vger.kernel.org,
	linux-stm32@st-md-mailman.stormreply.com,
	patches@opensource.cirrus.com, linux-clk@vger.kernel.org,
	linux-watchdog@vger.kernel.org,
	Sergio Prado <sergio.prado@e-labworks.com>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Sylwester Nawrocki <snawrocki@kernel.org>,
	Cedric Roux <sed@free.fr>, Lihua Yao <ylhuajnu@outlook.com>
Subject: Re: [PATCH 5/7] ARM: samsung: Kill useless HAVE_S3C2410_WATCHDOG
Date: Wed, 29 Jul 2020 10:02:45 -0700	[thread overview]
Message-ID: <20200729170245.GA177035@roeck-us.net> (raw)
In-Reply-To: <20200729160942.28867-6-krzk@kernel.org>

On Wed, Jul 29, 2020 at 06:09:40PM +0200, Krzysztof Kozlowski wrote:
> A separate Kconfig option HAVE_S3C2410_WATCHDOG for Samsung SoCs does
> not have sense, because:
> 1. All ARMv7 and ARMv8 Samsung SoCs have watchdog,
> 2. All architecture Kconfigs were selecting it (if WATCHDOG framework is
>    chosen),
> 3. HAVE_S3C2410_WATCHDOG is doing nothing except being a dependency of
>    actual Samsung SoC watchdog driver, which is enabled manually by
>    specific defconfigs.
> 
> HAVE_S3C2410_WATCHDOG can be safely removed.
> 

That is not really correct. HAVE_S3C2410_WATCHDOG is used to ensure
that users can only enable S3C2410_WATCHDOG if the watchdog actually
exists in a system. With this change, it can be enabled for all
architectures and platforms.

NACK.

Guenter

> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
> ---
>  arch/arm/Kconfig              | 1 -
>  arch/arm/mach-exynos/Kconfig  | 1 -
>  arch/arm/mach-s3c64xx/Kconfig | 2 --
>  arch/arm/mach-s5pv210/Kconfig | 1 -
>  arch/arm64/Kconfig.platforms  | 1 -
>  drivers/watchdog/Kconfig      | 8 --------
>  6 files changed, 14 deletions(-)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 7564f293f107..fe95777af653 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -504,7 +504,6 @@ config ARCH_S3C24XX
>  	select GPIOLIB
>  	select GENERIC_IRQ_MULTI_HANDLER
>  	select HAVE_S3C2410_I2C if I2C
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select HAVE_S3C_RTC if RTC_CLASS
>  	select NEED_MACH_IO_H
>  	select SAMSUNG_ATAGS
> diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
> index f185cd3d4c62..d2d249706ebb 100644
> --- a/arch/arm/mach-exynos/Kconfig
> +++ b/arch/arm/mach-exynos/Kconfig
> @@ -24,7 +24,6 @@ menuconfig ARCH_EXYNOS
>  	select HAVE_ARM_ARCH_TIMER if ARCH_EXYNOS5
>  	select HAVE_ARM_SCU if SMP
>  	select HAVE_S3C2410_I2C if I2C
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select HAVE_S3C_RTC if RTC_CLASS
>  	select PINCTRL
>  	select PINCTRL_EXYNOS
> diff --git a/arch/arm/mach-s3c64xx/Kconfig b/arch/arm/mach-s3c64xx/Kconfig
> index ac3e3563487f..e208c2b48853 100644
> --- a/arch/arm/mach-s3c64xx/Kconfig
> +++ b/arch/arm/mach-s3c64xx/Kconfig
> @@ -13,7 +13,6 @@ menuconfig ARCH_S3C64XX
>  	select GPIO_SAMSUNG if ATAGS
>  	select GPIOLIB
>  	select HAVE_S3C2410_I2C if I2C
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select HAVE_TCM
>  	select PLAT_SAMSUNG
>  	select PM_GENERIC_DOMAINS if PM
> @@ -165,7 +164,6 @@ config MACH_SMDK6410
>  	bool "SMDK6410"
>  	depends on ATAGS
>  	select CPU_S3C6410
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select S3C64XX_SETUP_FB_24BPP
>  	select S3C64XX_SETUP_I2C1
>  	select S3C64XX_SETUP_IDE
> diff --git a/arch/arm/mach-s5pv210/Kconfig b/arch/arm/mach-s5pv210/Kconfig
> index 03984a791879..b3db1191e437 100644
> --- a/arch/arm/mach-s5pv210/Kconfig
> +++ b/arch/arm/mach-s5pv210/Kconfig
> @@ -14,7 +14,6 @@ config ARCH_S5PV210
>  	select COMMON_CLK_SAMSUNG
>  	select GPIOLIB
>  	select HAVE_S3C2410_I2C if I2C
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select HAVE_S3C_RTC if RTC_CLASS
>  	select PINCTRL
>  	select PINCTRL_EXYNOS
> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
> index cd58f8495c45..d235b27cf372 100644
> --- a/arch/arm64/Kconfig.platforms
> +++ b/arch/arm64/Kconfig.platforms
> @@ -80,7 +80,6 @@ config ARCH_EXYNOS
>  	select EXYNOS_CHIPID
>  	select EXYNOS_PM_DOMAINS if PM_GENERIC_DOMAINS
>  	select EXYNOS_PMU
> -	select HAVE_S3C2410_WATCHDOG if WATCHDOG
>  	select HAVE_S3C_RTC if RTC_CLASS
>  	select PINCTRL
>  	select PINCTRL_EXYNOS
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 4f4687c46d38..ae86ea135d2b 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -478,16 +478,8 @@ config IXP4XX_WATCHDOG
>  
>  	  Say N if you are unsure.
>  
> -config HAVE_S3C2410_WATCHDOG
> -	bool
> -	help
> -	  This will include watchdog timer support for Samsung SoCs. If
> -	  you want to include watchdog support for any machine, kindly
> -	  select this in the respective mach-XXXX/Kconfig file.
> -
>  config S3C2410_WATCHDOG
>  	tristate "S3C2410 Watchdog"
> -	depends on HAVE_S3C2410_WATCHDOG || COMPILE_TEST
>  	select WATCHDOG_CORE
>  	select MFD_SYSCON if ARCH_EXYNOS
>  	help
> -- 
> 2.17.1
> 