watchdog: qcom_wdt: set WDOG_HW_RUNNING bit when appropriate (8650d0f9) · Commits · 戴 / test

If the watchdog hardware is enabled/running during boot, e.g. due to a boot loader configuring it, we must tell the watchdog framework about this fact so that it can ping the watchdog until userspace opens the device and takes over control. Do so using the WDOG_HW_RUNNING flag that exists for exactly that use-case. Signed-off-by:

Robert Marko <robert.marko@sartura.hr> Cc: Luka Perkov <luka.perkov@sartura.hr> Reviewed-by:

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

Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/r/20201031121115.542752-1-robert.marko@sartura.hr Signed-off-by:

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

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

drivers/watchdog/qcom-wdt.c

+18 −0

Original line number	Diff line number	Diff line
		@@ -152,6 +152,13 @@ static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action,
		return 0;
		}

		static int qcom_wdt_is_running(struct watchdog_device *wdd)
		{
		struct qcom_wdt *wdt = to_qcom_wdt(wdd);

		return (readl(wdt_addr(wdt, WDT_EN)) & QCOM_WDT_ENABLE);
		}

		static const struct watchdog_ops qcom_wdt_ops = {
		.start = qcom_wdt_start,
		.stop = qcom_wdt_stop,
		@@ -294,6 +301,17 @@ static int qcom_wdt_probe(struct platform_device *pdev)
		wdt->wdd.timeout = min(wdt->wdd.max_timeout, 30U);
		watchdog_init_timeout(&wdt->wdd, 0, dev);

		/*
		* If WDT is already running, call WDT start which
		* will stop the WDT, set timeouts as bootloader
		* might use different ones and set running bit
		* to inform the WDT subsystem to ping the WDT
		*/
		if (qcom_wdt_is_running(&wdt->wdd)) {
		qcom_wdt_start(&wdt->wdd);
		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
		}

		ret = devm_watchdog_register_device(dev, &wdt->wdd);
		if (ret)
		return ret;

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