openwrt/target/linux/rdc/patches-2.6.32/110-rdc321x_watchdog_fix.patch

--- a/drivers/watchdog/rdc321x_wdt.c
+++ b/drivers/watchdog/rdc321x_wdt.c
@@ -36,111 +36,99 @@
 #include <linux/watchdog.h>
 #include <linux/io.h>
 #include <linux/uaccess.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
 #include <linux/mfd/rdc321x.h>
 
-#define RDC_WDT_MASK	0x80000000 /* Mask */
+#define RDC321X_WDT_REG 0x00000044
+
 #define RDC_WDT_EN	0x00800000 /* Enable bit */
-#define RDC_WDT_WTI	0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
-#define RDC_WDT_RST	0x00100000 /* Reset bit */
-#define RDC_WDT_WIF	0x00040000 /* WDT IRQ Flag */
-#define RDC_WDT_IRT	0x00000100 /* IRQ Routing table */
-#define RDC_WDT_CNT	0x00000001 /* WDT count */
+#define RDC_WDT_WDTIRQ	0x00400000 /* Create WDT IRQ before CPU reset */
+#define RDC_WDT_NMIIRQ	0x00200000 /* Create NMI IRQ before CPU reset */
+#define RDC_WDT_RST	0x00100000 /* Reset wdt */
+#define RDC_WDT_NIF	0x00080000 /* NMI interrupt occured */
+#define RDC_WDT_WIF	0x00040000 /* WDT interrupt occured */
+#define RDC_WDT_IRT	0x00000700 /* IRQ Routing table */
+#define RDC_WDT_CNT	0x0000007F /* WDT count */
 
-#define RDC_CLS_TMR	0x80003844 /* Clear timer */
+/* default counter value (2.34 s) */
+#define RDC_WDT_DFLT_CNT 0x00000040
 
-#define RDC_WDT_INTERVAL	(HZ/10+1)
+#define RDC_WDT_SETUP (RDC_WDT_EN | RDC_WDT_NMIIRQ | RDC_WDT_RST | RDC_WDT_DFLT_CNT)
 
 static int ticks = 1000;
 
 /* some device data */
 
 static struct {
-	struct completion stop;
-	int running;
 	struct timer_list timer;
-	int queue;
-	int default_ticks;
-	unsigned long inuse;
-	spinlock_t lock;
+	int seconds_left;
+	int total_seconds;
+	bool inuse;
+	bool running;
+	bool close_expected;
+
 	struct pci_dev *sb_pdev;
 	int base_reg;
 } rdc321x_wdt_device;
 
-/* generic helper functions */
+static struct watchdog_info ident = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
+	.identity = "RDC321x WDT",
+};
 
-static void rdc321x_wdt_trigger(unsigned long unused)
+
+/* generic helper functions */
+static void rdc321x_wdt_timer(unsigned long unused)
 {
-	unsigned long flags;
-	u32 val;
+        if (!rdc321x_wdt_device.running) {
+                pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+						rdc321x_wdt_device.base_reg, 0);
+                return;
+        }
 
-	if (rdc321x_wdt_device.running)
-		ticks--;
+        rdc321x_wdt_device.seconds_left--;
 
-	/* keep watchdog alive */
-	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
-	pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
-					rdc321x_wdt_device.base_reg, &val);
-	val |= RDC_WDT_EN;
-	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
-					rdc321x_wdt_device.base_reg, val);
-	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
+        if (rdc321x_wdt_device.seconds_left < 1)
+                return;
 
-	/* requeue?? */
-	if (rdc321x_wdt_device.queue && ticks)
-		mod_timer(&rdc321x_wdt_device.timer,
-				jiffies + RDC_WDT_INTERVAL);
-	else {
-		/* ticks doesn't matter anyway */
-		complete(&rdc321x_wdt_device.stop);
-	}
+	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+				rdc321x_wdt_device.base_reg, RDC_WDT_SETUP);
 
+        mod_timer(&rdc321x_wdt_device.timer, HZ * 2 + jiffies);
 }
 
 static void rdc321x_wdt_reset(void)
 {
-	ticks = rdc321x_wdt_device.default_ticks;
+	rdc321x_wdt_device.seconds_left = rdc321x_wdt_device.total_seconds;
 }
 
 static void rdc321x_wdt_start(void)
 {
-	unsigned long flags;
-
-	if (!rdc321x_wdt_device.queue) {
-		rdc321x_wdt_device.queue = 1;
-
-		/* Clear the timer */
-		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
-		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
-				rdc321x_wdt_device.base_reg, RDC_CLS_TMR);
-
-		/* Enable watchdog and set the timeout to 81.92 us */
-		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
-					rdc321x_wdt_device.base_reg,
-					RDC_WDT_EN | RDC_WDT_CNT);
-		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
+	if (rdc321x_wdt_device.running)
+		return;
 
-		mod_timer(&rdc321x_wdt_device.timer,
-				jiffies + RDC_WDT_INTERVAL);
-	}
+	rdc321x_wdt_device.seconds_left = rdc321x_wdt_device.total_seconds;
+	rdc321x_wdt_device.running = true;
+	rdc321x_wdt_timer(0);
 
-	/* if process dies, counter is not decremented */
-	rdc321x_wdt_device.running++;
+	return;
 }
 
 static int rdc321x_wdt_stop(void)
 {
-	if (rdc321x_wdt_device.running)
-		rdc321x_wdt_device.running = 0;
+	if (WATCHDOG_NOWAYOUT)
+		return -ENOSYS;
 
-	ticks = rdc321x_wdt_device.default_ticks;
+	rdc321x_wdt_device.running = false;
 
-	return -EIO;
+	return 0;
 }
 
 /* filesystem operations */
 static int rdc321x_wdt_open(struct inode *inode, struct file *file)
 {
-	if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
+	if (xchg(&rdc321x_wdt_device.inuse, true))
 		return -EBUSY;
 
 	return nonseekable_open(inode, file);
@@ -148,7 +136,16 @@ static int rdc321x_wdt_open(struct inode
 
 static int rdc321x_wdt_release(struct inode *inode, struct file *file)
 {
-	clear_bit(0, &rdc321x_wdt_device.inuse);
+	int ret;
+
+	if (rdc321x_wdt_device.close_expected) {
+		ret = rdc321x_wdt_stop();
+		if (ret)
+			return ret;
+	}
+
+	rdc321x_wdt_device.inuse = false;
+
 	return 0;
 }
 
@@ -156,30 +153,29 @@ static long rdc321x_wdt_ioctl(struct fil
 				unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
-	u32 value;
-	static struct watchdog_info ident = {
-		.options = WDIOF_CARDRESET,
-		.identity = "RDC321x WDT",
-	};
-	unsigned long flags;
+	int value;
 
 	switch (cmd) {
 	case WDIOC_KEEPALIVE:
 		rdc321x_wdt_reset();
 		break;
-	case WDIOC_GETSTATUS:
-		/* Read the value from the DATA register */
-		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
-		pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
-					rdc321x_wdt_device.base_reg, &value);
-		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
-		if (copy_to_user(argp, &value, sizeof(u32)))
-			return -EFAULT;
-		break;
 	case WDIOC_GETSUPPORT:
 		if (copy_to_user(argp, &ident, sizeof(ident)))
 			return -EFAULT;
 		break;
+	case WDIOC_SETTIMEOUT:
+		if (copy_from_user(&rdc321x_wdt_device.total_seconds, argp, sizeof(int)))
+			return -EFAULT;
+		rdc321x_wdt_device.seconds_left = rdc321x_wdt_device.total_seconds;
+		break;
+	case WDIOC_GETTIMEOUT:
+		if (copy_to_user(argp, &rdc321x_wdt_device.total_seconds, sizeof(int)))
+			return -EFAULT;
+		break;
+	case WDIOC_GETTIMELEFT:
+		if (copy_to_user(argp, &rdc321x_wdt_device.seconds_left, sizeof(int)))
+			return -EFAULT;
+		break;
 	case WDIOC_SETOPTIONS:
 		if (copy_from_user(&value, argp, sizeof(int)))
 			return -EFAULT;
@@ -194,17 +190,34 @@ static long rdc321x_wdt_ioctl(struct fil
 		}
 		break;
 	default:
-		return -ENOTTY;
+		return -EINVAL;
 	}
+
 	return 0;
 }
 
 static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
 				size_t count, loff_t *ppos)
 {
+	size_t i;
+
 	if (!count)
 		return -EIO;
 
+	rdc321x_wdt_device.close_expected = false;
+
+	for (i = 0; i != count; i++) {
+		char c;
+
+		if (get_user(c, buf + i))
+			return -EFAULT;
+
+		if (c == 'V') {
+			rdc321x_wdt_device.close_expected = true;
+			break;
+		}
+	}
+
 	rdc321x_wdt_reset();
 
 	return count;
@@ -246,27 +259,18 @@ static int __devinit rdc321x_wdt_probe(s
 	rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
 	rdc321x_wdt_device.base_reg = r->start;
 
+	rdc321x_wdt_device.running = false;
+	rdc321x_wdt_device.close_expected = false;
+	rdc321x_wdt_device.inuse = 0;
+	setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_timer, 0);
+	rdc321x_wdt_device.total_seconds = 100;
+
 	err = misc_register(&rdc321x_wdt_misc);
 	if (err < 0) {
 		dev_err(&pdev->dev, "misc_register failed\n");
 		return err;
 	}
 
-	spin_lock_init(&rdc321x_wdt_device.lock);
-
-	/* Reset the watchdog */
-	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
-				rdc321x_wdt_device.base_reg, RDC_WDT_RST);
-
-	init_completion(&rdc321x_wdt_device.stop);
-	rdc321x_wdt_device.queue = 0;
-
-	clear_bit(0, &rdc321x_wdt_device.inuse);
-
-	setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
-
-	rdc321x_wdt_device.default_ticks = ticks;
-
 	dev_info(&pdev->dev, "watchdog init success\n");
 
 	return 0;
@@ -274,10 +278,11 @@ static int __devinit rdc321x_wdt_probe(s
 
 static int __devexit rdc321x_wdt_remove(struct platform_device *pdev)
 {
-	if (rdc321x_wdt_device.queue) {
-		rdc321x_wdt_device.queue = 0;
-		wait_for_completion(&rdc321x_wdt_device.stop);
-	}
+	if (rdc321x_wdt_device.inuse)
+		rdc321x_wdt_device.inuse = 0;
+
+	while (timer_pending(&rdc321x_wdt_device.timer))
+		msleep(100);
 
 	misc_deregister(&rdc321x_wdt_misc);