watchdog: imx2_wdt: add restart handler support (334a9d81) · Commits · 戴 / test

drivers/watchdog/imx2_wdt.c

+37 −0

Original line number	Diff line number	Diff line
		@@ -22,14 +22,17 @@
		*/

		#include <linux/clk.h>
		#include <linux/delay.h>
		#include <linux/init.h>
		#include <linux/io.h>
		#include <linux/jiffies.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/moduleparam.h>
		#include <linux/notifier.h>
		#include <linux/of_address.h>
		#include <linux/platform_device.h>
		#include <linux/reboot.h>
		#include <linux/regmap.h>
		#include <linux/timer.h>
		#include <linux/watchdog.h>
		@@ -59,6 +62,7 @@ struct imx2_wdt_device {
		struct regmap *regmap;
		struct timer_list timer; /* Pings the watchdog when closed */
		struct watchdog_device wdog;
		struct notifier_block restart_handler;
		};

		static bool nowayout = WATCHDOG_NOWAYOUT;
		@@ -77,6 +81,31 @@ static const struct watchdog_info imx2_wdt_info = {
		.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
		};

		static int imx2_restart_handler(struct notifier_block *this, unsigned long mode,
		void *cmd)
		{
		unsigned int wcr_enable = IMX2_WDT_WCR_WDE;
		struct imx2_wdt_device *wdev = container_of(this,
		struct imx2_wdt_device,
		restart_handler);
		/* Assert SRS signal */
		regmap_write(wdev->regmap, 0, wcr_enable);
		/*
		* Due to imx6q errata ERR004346 (WDOG: WDOG SRS bit requires to be
		* written twice), we add another two writes to ensure there must be at
		* least two writes happen in the same one 32kHz clock period. We save
		* the target check here, since the writes shouldn't be a huge burden
		* for other platforms.
		*/
		regmap_write(wdev->regmap, 0, wcr_enable);
		regmap_write(wdev->regmap, 0, wcr_enable);

		/* wait for reset to assert... */
		mdelay(500);

		return NOTIFY_DONE;
		}

		static inline void imx2_wdt_setup(struct watchdog_device *wdog)
		{
		struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
		@@ -251,6 +280,12 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
		return ret;
		}

		wdev->restart_handler.notifier_call = imx2_restart_handler;
		wdev->restart_handler.priority = 128;
		ret = register_restart_handler(&wdev->restart_handler);
		if (ret)
		dev_err(&pdev->dev, "cannot register restart handler\n");

		dev_info(&pdev->dev, "timeout %d sec (nowayout=%d)\n",
		wdog->timeout, nowayout);

		@@ -262,6 +297,8 @@ static int __exit imx2_wdt_remove(struct platform_device *pdev)
		struct watchdog_device *wdog = platform_get_drvdata(pdev);
		struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);

		unregister_restart_handler(&wdev->restart_handler);

		watchdog_unregister_device(wdog);

		if (imx2_wdt_is_running(wdev)) {

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