drivers: watchdog: stm32_iwdg: set WDOG_HW_RUNNING at probe (85fdc63f) · Commits · 戴 / test

If the watchdog hardware is already enabled during the boot process, when the Linux watchdog driver loads, it should start/reset the watchdog and tell the watchdog framework. As a result, ping can be generated from the watchdog framework (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is set), until the userspace watchdog daemon takes over control Fixes: ("watchdog: Add STM32 IWDG driver") Signed-off-by:

Christophe Roullier <christophe.roullier@st.com> Reviewed-by:

Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20191122132246.8473-1-christophe.roullier@st.com Signed-off-by:

Guenter Roeck <linux@roeck-us.net> Signed-off-by:

Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/stm32_iwdg.c

+18 −0

Original line number	Diff line number	Diff line
		@@ -262,6 +262,24 @@ static int stm32_iwdg_probe(struct platform_device *pdev)
		watchdog_set_nowayout(wdd, WATCHDOG_NOWAYOUT);
		watchdog_init_timeout(wdd, 0, dev);

		/*
		* In case of CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is set
		* (Means U-Boot/bootloaders leaves the watchdog running)
		* When we get here we should make a decision to prevent
		* any side effects before user space daemon will take care of it.
		* The best option, taking into consideration that there is no
		* way to read values back from hardware, is to enforce watchdog
		* being run with deterministic values.
		*/
		if (IS_ENABLED(CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED)) {
		ret = stm32_iwdg_start(wdd);
		if (ret)
		return ret;

		/* Make sure the watchdog is serviced */
		set_bit(WDOG_HW_RUNNING, &wdd->status);
		}

		ret = devm_watchdog_register_device(dev, wdd);
		if (ret)
		return ret;

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