watchdog: shwdt: Migrate to per-device locking. (f9fb360c) · Commits · jan.koester / Linux

drivers/watchdog/shwdt.c

+19 −15

Original line number	Original line	Diff line number	Diff line
	@@ -25,6 +25,7 @@
	#include <linux/platform_device.h>		#include <linux/platform_device.h>
	#include <linux/init.h>		#include <linux/init.h>
	#include <linux/types.h>		#include <linux/types.h>
			#include <linux/spinlock.h>
	#include <linux/miscdevice.h>		#include <linux/miscdevice.h>
	#include <linux/watchdog.h>		#include <linux/watchdog.h>
	#include <linux/fs.h>		#include <linux/fs.h>
	@@ -65,8 +66,6 @@
	static int clock_division_ratio = WTCSR_CKS_4096;		static int clock_division_ratio = WTCSR_CKS_4096;
	#define next_ping_period(cks) (jiffies + msecs_to_jiffies(cks - 4))		#define next_ping_period(cks) (jiffies + msecs_to_jiffies(cks - 4))

	static DEFINE_SPINLOCK(shwdt_lock);

	#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */		#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */
	static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */		static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
	static bool nowayout = WATCHDOG_NOWAYOUT;		static bool nowayout = WATCHDOG_NOWAYOUT;
	@@ -75,6 +74,7 @@ static unsigned long next_heartbeat;
	struct sh_wdt {		struct sh_wdt {
	void __iomem *base;		void __iomem *base;
	struct device *dev;		struct device *dev;
			spinlock_t lock;

	struct timer_list timer;		struct timer_list timer;

	@@ -88,7 +88,7 @@ static int sh_wdt_start(struct watchdog_device *wdt_dev)
	unsigned long flags;		unsigned long flags;
	u8 csr;		u8 csr;

	spin_lock_irqsave(&shwdt_lock, flags);		spin_lock_irqsave(&wdt->lock, flags);

	next_heartbeat = jiffies + (heartbeat * HZ);		next_heartbeat = jiffies + (heartbeat * HZ);
	mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));		mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
	@@ -117,7 +117,7 @@ static int sh_wdt_start(struct watchdog_device *wdt_dev)
	csr &= ~RSTCSR_RSTS;		csr &= ~RSTCSR_RSTS;
	sh_wdt_write_rstcsr(csr);		sh_wdt_write_rstcsr(csr);
	#endif		#endif
	spin_unlock_irqrestore(&shwdt_lock, flags);		spin_unlock_irqrestore(&wdt->lock, flags);

	return 0;		return 0;
	}		}
	@@ -128,7 +128,7 @@ static int sh_wdt_stop(struct watchdog_device *wdt_dev)
	unsigned long flags;		unsigned long flags;
	u8 csr;		u8 csr;

	spin_lock_irqsave(&shwdt_lock, flags);		spin_lock_irqsave(&wdt->lock, flags);

	del_timer(&wdt->timer);		del_timer(&wdt->timer);

	@@ -136,33 +136,35 @@ static int sh_wdt_stop(struct watchdog_device *wdt_dev)
	csr &= ~WTCSR_TME;		csr &= ~WTCSR_TME;
	sh_wdt_write_csr(csr);		sh_wdt_write_csr(csr);

	spin_unlock_irqrestore(&shwdt_lock, flags);		spin_unlock_irqrestore(&wdt->lock, flags);

	return 0;		return 0;
	}		}

	static int sh_wdt_keepalive(struct watchdog_device *wdt_dev)		static int sh_wdt_keepalive(struct watchdog_device *wdt_dev)
	{		{
			struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
	unsigned long flags;		unsigned long flags;

	spin_lock_irqsave(&shwdt_lock, flags);		spin_lock_irqsave(&wdt->lock, flags);
	next_heartbeat = jiffies + (heartbeat * HZ);		next_heartbeat = jiffies + (heartbeat * HZ);
	spin_unlock_irqrestore(&shwdt_lock, flags);		spin_unlock_irqrestore(&wdt->lock, flags);

	return 0;		return 0;
	}		}

	static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t)		static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t)
	{		{
			struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
	unsigned long flags;		unsigned long flags;

	if (unlikely(t < 1 \|\| t > 3600)) /* arbitrary upper limit */		if (unlikely(t < 1 \|\| t > 3600)) /* arbitrary upper limit */
	return -EINVAL;		return -EINVAL;

	spin_lock_irqsave(&shwdt_lock, flags);		spin_lock_irqsave(&wdt->lock, flags);
	heartbeat = t;		heartbeat = t;
	wdt_dev->timeout = t;		wdt_dev->timeout = t;
	spin_unlock_irqrestore(&shwdt_lock, flags);		spin_unlock_irqrestore(&wdt->lock, flags);

	return 0;		return 0;
	}		}
	@@ -172,7 +174,7 @@ static void sh_wdt_ping(unsigned long data)
	struct sh_wdt wdt = (struct sh_wdt )data;		struct sh_wdt wdt = (struct sh_wdt )data;
	unsigned long flags;		unsigned long flags;

	spin_lock_irqsave(&shwdt_lock, flags);		spin_lock_irqsave(&wdt->lock, flags);
	if (time_before(jiffies, next_heartbeat)) {		if (time_before(jiffies, next_heartbeat)) {
	u8 csr;		u8 csr;

	@@ -186,7 +188,7 @@ static void sh_wdt_ping(unsigned long data)
	} else		} else
	dev_warn(wdt->dev, "Heartbeat lost! Will not ping "		dev_warn(wdt->dev, "Heartbeat lost! Will not ping "
	"the watchdog\n");		"the watchdog\n");
	spin_unlock_irqrestore(&shwdt_lock, flags);		spin_unlock_irqrestore(&wdt->lock, flags);
	}		}

	static const struct watchdog_info sh_wdt_info = {		static const struct watchdog_info sh_wdt_info = {
	@@ -238,12 +240,17 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev)

	wdt->dev = &pdev->dev;		wdt->dev = &pdev->dev;

			watchdog_set_nowayout(&sh_wdt_dev, nowayout);
			watchdog_set_drvdata(&sh_wdt_dev, wdt);

	wdt->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));		wdt->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
	if (unlikely(!wdt->base)) {		if (unlikely(!wdt->base)) {
	rc = -ENXIO;		rc = -ENXIO;
	goto out_err;		goto out_err;
	}		}

			spin_lock_init(&wdt->lock);

	rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat);		rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat);
	if (unlikely(rc)) {		if (unlikely(rc)) {
	/* Default timeout if invalid */		/* Default timeout if invalid */
	@@ -257,9 +264,6 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev)
	dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n",		dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n",
	sh_wdt_dev.timeout, nowayout);		sh_wdt_dev.timeout, nowayout);

	watchdog_set_nowayout(&sh_wdt_dev, nowayout);
	watchdog_set_drvdata(&sh_wdt_dev, wdt);

	rc = watchdog_register_device(&sh_wdt_dev);		rc = watchdog_register_device(&sh_wdt_dev);
	if (unlikely(rc)) {		if (unlikely(rc)) {
	dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc);		dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc);