watchdog: shwdt: Conversion to watchdog core.

Fairly straightforward conversion to utilize watchdog core support.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

drivers/watchdog/Kconfig

@@ -1138,6 +1138,7 @@ config ZVM_WATCHDOG
 config SH_WDT
 	tristate "SuperH Watchdog"
 	depends on SUPERH && (CPU_SH3 || CPU_SH4)
+	select WATCHDOG_CORE
 	help
 	  This driver adds watchdog support for the integrated watchdog in the
 	  SuperH processors. If you have one of these processors and wish

drivers/watchdog/shwdt.c

@@ -27,12 +27,10 @@
 #include <linux/types.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
-#include <linux/ioport.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/io.h>
-#include <linux/uaccess.h>
 #include <asm/watchdog.h>
 
 #define DRV_NAME "sh-wdt"
@@ -67,8 +65,6 @@
 static int clock_division_ratio = WTCSR_CKS_4096;
 #define next_ping_period(cks)	(jiffies + msecs_to_jiffies(cks - 4))
 
-static const struct watchdog_info sh_wdt_info;
-static struct platform_device *sh_wdt_dev;
 static DEFINE_SPINLOCK(shwdt_lock);
 
 #define WATCHDOG_HEARTBEAT 30			/* 30 sec default heartbeat */
@@ -86,8 +82,9 @@ struct sh_wdt {
 	char			expect_close;
 };
 
-static void sh_wdt_start(struct sh_wdt *wdt)
+static int sh_wdt_start(struct watchdog_device *wdt_dev)
 {
+	struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
 	unsigned long flags;
 	u8 csr;
 
@@ -121,10 +118,13 @@ static void sh_wdt_start(struct sh_wdt *wdt)
 	sh_wdt_write_rstcsr(csr);
 #endif
 	spin_unlock_irqrestore(&shwdt_lock, flags);
+
+	return 0;
 }
 
-static void sh_wdt_stop(struct sh_wdt *wdt)
+static int sh_wdt_stop(struct watchdog_device *wdt_dev)
 {
+	struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
 	unsigned long flags;
 	u8 csr;
 
@@ -137,18 +137,22 @@ static void sh_wdt_stop(struct sh_wdt *wdt)
 	sh_wdt_write_csr(csr);
 
 	spin_unlock_irqrestore(&shwdt_lock, flags);
+
+	return 0;
 }
 
-static inline void sh_wdt_keepalive(struct sh_wdt *wdt)
+static int sh_wdt_keepalive(struct watchdog_device *wdt_dev)
 {
 	unsigned long flags;
 
 	spin_lock_irqsave(&shwdt_lock, flags);
 	next_heartbeat = jiffies + (heartbeat * HZ);
 	spin_unlock_irqrestore(&shwdt_lock, flags);
+
+	return 0;
 }
 
-static int sh_wdt_set_heartbeat(int t)
+static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t)
 {
 	unsigned long flags;
 
@@ -157,7 +161,9 @@ static int sh_wdt_set_heartbeat(int t)
 
 	spin_lock_irqsave(&shwdt_lock, flags);
 	heartbeat = t;
+	wdt_dev->timeout = t;
 	spin_unlock_irqrestore(&shwdt_lock, flags);
+
 	return 0;
 }
 
@@ -183,123 +189,6 @@ static void sh_wdt_ping(unsigned long data)
 	spin_unlock_irqrestore(&shwdt_lock, flags);
 }
 
-static int sh_wdt_open(struct inode *inode, struct file *file)
-{
-	struct sh_wdt *wdt = platform_get_drvdata(sh_wdt_dev);
-
-	if (test_and_set_bit(0, &wdt->enabled))
-		return -EBUSY;
-	if (nowayout)
-		__module_get(THIS_MODULE);
-
-	file->private_data = wdt;
-
-	sh_wdt_start(wdt);
-
-	return nonseekable_open(inode, file);
-}
-
-static int sh_wdt_close(struct inode *inode, struct file *file)
-{
-	struct sh_wdt *wdt = file->private_data;
-
-	if (wdt->expect_close == 42) {
-		sh_wdt_stop(wdt);
-	} else {
-		dev_crit(wdt->dev, "Unexpected close, not "
-		         "stopping watchdog!\n");
-		sh_wdt_keepalive(wdt);
-	}
-
-	clear_bit(0, &wdt->enabled);
-	wdt->expect_close = 0;
-
-	return 0;
-}
-
-static ssize_t sh_wdt_write(struct file *file, const char *buf,
-			    size_t count, loff_t *ppos)
-{
-	struct sh_wdt *wdt = file->private_data;
-
-	if (count) {
-		if (!nowayout) {
-			size_t i;
-
-			wdt->expect_close = 0;
-
-			for (i = 0; i != count; i++) {
-				char c;
-				if (get_user(c, buf + i))
-					return -EFAULT;
-				if (c == 'V')
-					wdt->expect_close = 42;
-			}
-		}
-		sh_wdt_keepalive(wdt);
-	}
-
-	return count;
-}
-
-static long sh_wdt_ioctl(struct file *file, unsigned int cmd,
-							unsigned long arg)
-{
-	struct sh_wdt *wdt = file->private_data;
-	int new_heartbeat;
-	int options, retval = -EINVAL;
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user((struct watchdog_info *)arg,
-			  &sh_wdt_info, sizeof(sh_wdt_info)) ? -EFAULT : 0;
-	case WDIOC_GETSTATUS:
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(0, (int *)arg);
-	case WDIOC_SETOPTIONS:
-		if (get_user(options, (int *)arg))
-			return -EFAULT;
-
-		if (options & WDIOS_DISABLECARD) {
-			sh_wdt_stop(wdt);
-			retval = 0;
-		}
-
-		if (options & WDIOS_ENABLECARD) {
-			sh_wdt_start(wdt);
-			retval = 0;
-		}
-
-		return retval;
-	case WDIOC_KEEPALIVE:
-		sh_wdt_keepalive(wdt);
-		return 0;
-	case WDIOC_SETTIMEOUT:
-		if (get_user(new_heartbeat, (int *)arg))
-			return -EFAULT;
-
-		if (sh_wdt_set_heartbeat(new_heartbeat))
-			return -EINVAL;
-
-		sh_wdt_keepalive(wdt);
-		/* Fall */
-	case WDIOC_GETTIMEOUT:
-		return put_user(heartbeat, (int *)arg);
-	default:
-		return -ENOTTY;
-	}
-	return 0;
-}
-
-static const struct file_operations sh_wdt_fops = {
-	.owner		= THIS_MODULE,
-	.llseek		= no_llseek,
-	.write		= sh_wdt_write,
-	.unlocked_ioctl	= sh_wdt_ioctl,
-	.open		= sh_wdt_open,
-	.release	= sh_wdt_close,
-};
-
 static const struct watchdog_info sh_wdt_info = {
 	.options		= WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
 				  WDIOF_MAGICCLOSE,
@@ -307,10 +196,17 @@ static const struct watchdog_info sh_wdt_info = {
 	.identity		= "SH WDT",
 };
 
-static struct miscdevice sh_wdt_miscdev = {
-	.minor		= WATCHDOG_MINOR,
-	.name		= "watchdog",
-	.fops		= &sh_wdt_fops,
+static const struct watchdog_ops sh_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= sh_wdt_start,
+	.stop		= sh_wdt_stop,
+	.ping		= sh_wdt_keepalive,
+	.set_timeout	= sh_wdt_set_heartbeat,
+};
+
+static struct watchdog_device sh_wdt_dev = {
+	.info	= &sh_wdt_info,
+	.ops	= &sh_wdt_ops,
 };
 
 static int __devinit sh_wdt_probe(struct platform_device *pdev)
@@ -348,13 +244,25 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev)
 		goto out_err;
 	}
 
-	sh_wdt_miscdev.parent = wdt->dev;
+	rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat);
+	if (unlikely(rc)) {
+		/* Default timeout if invalid */
+		sh_wdt_set_heartbeat(&sh_wdt_dev, WATCHDOG_HEARTBEAT);
+
+		dev_warn(&pdev->dev,
+			 "heartbeat value must be 1<=x<=3600, using %d\n",
+			 sh_wdt_dev.timeout);
+	}
+
+	dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n",
+		 sh_wdt_dev.timeout, nowayout);
+
+	watchdog_set_nowayout(&sh_wdt_dev, nowayout);
+	watchdog_set_drvdata(&sh_wdt_dev, wdt);
 
-	rc = misc_register(&sh_wdt_miscdev);
+	rc = watchdog_register_device(&sh_wdt_dev);
 	if (unlikely(rc)) {
-		dev_err(&pdev->dev,
-			"Can't register miscdev on minor=%d (err=%d)\n",
-						sh_wdt_miscdev.minor, rc);
+		dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc);
 		goto out_unmap;
 	}
 
@@ -364,7 +272,6 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev)
 	wdt->timer.expires	= next_ping_period(clock_division_ratio);
 
 	platform_set_drvdata(pdev, wdt);
-	sh_wdt_dev = pdev;
 
 	dev_info(&pdev->dev, "initialized.\n");
 
@@ -387,9 +294,7 @@ static int __devexit sh_wdt_remove(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, NULL);
 
-	misc_deregister(&sh_wdt_miscdev);
-
-	sh_wdt_dev = NULL;
+	watchdog_unregister_device(&sh_wdt_dev);
 
 	devm_release_mem_region(&pdev->dev, res->start, resource_size(res));
 	devm_iounmap(&pdev->dev, wdt->base);
@@ -400,9 +305,7 @@ static int __devexit sh_wdt_remove(struct platform_device *pdev)
 
 static void sh_wdt_shutdown(struct platform_device *pdev)
 {
-	struct sh_wdt *wdt = platform_get_drvdata(pdev);
-
-	sh_wdt_stop(wdt);
+	sh_wdt_stop(&sh_wdt_dev);
 }
 
 static struct platform_driver sh_wdt_driver = {
@@ -418,8 +321,6 @@ static struct platform_driver sh_wdt_driver = {
 
 static int __init sh_wdt_init(void)
 {
-	int rc;
-
 	if (unlikely(clock_division_ratio < 0x5 ||
 		     clock_division_ratio > 0x7)) {
 		clock_division_ratio = WTCSR_CKS_4096;
@@ -428,17 +329,6 @@ static int __init sh_wdt_init(void)
 			clock_division_ratio);
 	}
 
-	rc = sh_wdt_set_heartbeat(heartbeat);
-	if (unlikely(rc)) {
-		heartbeat = WATCHDOG_HEARTBEAT;
-
-		pr_info("heartbeat value must be 1<=x<=3600, using %d\n",
-			heartbeat);
-	}
-
-	pr_info("configured with heartbeat=%d sec (nowayout=%d)\n",
-		heartbeat, nowayout);
-
 	return platform_driver_register(&sh_wdt_driver);
 }