1 files changed, 53 insertions, 20 deletions

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index b9dc2c352151..6798addabd5a 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -275,15 +275,18 @@ static int watchdog_start(struct watchdog_device *wdd)
 	set_bit(_WDOG_KEEPALIVE, &wd_data->status);
 
 	started_at = ktime_get();
-	if (watchdog_hw_running(wdd) && wdd->ops->ping)
-		err = wdd->ops->ping(wdd);
-	else
+	if (watchdog_hw_running(wdd) && wdd->ops->ping) {
+		err = __watchdog_ping(wdd);
+		if (err == 0)
+			set_bit(WDOG_ACTIVE, &wdd->status);
+	} else {
 		err = wdd->ops->start(wdd);
-	if (err == 0) {
-		set_bit(WDOG_ACTIVE, &wdd->status);
-		wd_data->last_keepalive = started_at;
-		wd_data->last_hw_keepalive = started_at;
-		watchdog_update_worker(wdd);
+		if (err == 0) {
+			set_bit(WDOG_ACTIVE, &wdd->status);
+			wd_data->last_keepalive = started_at;
+			wd_data->last_hw_keepalive = started_at;
+			watchdog_update_worker(wdd);
+		}
 	}
 
 	return err;
@@ -587,7 +590,7 @@ static DEVICE_ATTR_RW(pretimeout_governor);
 static umode_t wdt_is_visible(struct kobject *kobj, struct attribute *attr,
 				int n)
 {
-	struct device *dev = container_of(kobj, struct device, kobj);
+	struct device *dev = kobj_to_dev(kobj);
 	struct watchdog_device *wdd = dev_get_drvdata(dev);
 	umode_t mode = attr->mode;
 
@@ -776,7 +779,7 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
 		err = watchdog_ping(wdd);
 		if (err < 0)
 			break;
-		/* fall through */
+		fallthrough;
 	case WDIOC_GETTIMEOUT:
 		/* timeout == 0 means that we don't know the timeout */
 		if (wdd->timeout == 0) {
@@ -916,7 +919,7 @@ static int watchdog_release(struct inode *inode, struct file *file)
 	 * or if WDIOF_MAGICCLOSE is not set. If nowayout was set then
 	 * watchdog_stop will fail.
 	 */
-	if (!test_bit(WDOG_ACTIVE, &wdd->status))
+	if (!watchdog_active(wdd))
 		err = 0;
 	else if (test_and_clear_bit(_WDOG_ALLOW_RELEASE, &wd_data->status) ||
 		 !(wdd->info->options & WDIOF_MAGICCLOSE))
@@ -994,6 +997,15 @@ static int watchdog_cdev_register(struct watchdog_device *wdd)
 	if (IS_ERR_OR_NULL(watchdog_kworker))
 		return -ENODEV;
 
+	device_initialize(&wd_data->dev);
+	wd_data->dev.devt = MKDEV(MAJOR(watchdog_devt), wdd->id);
+	wd_data->dev.class = &watchdog_class;
+	wd_data->dev.parent = wdd->parent;
+	wd_data->dev.groups = wdd->groups;
+	wd_data->dev.release = watchdog_core_data_release;
+	dev_set_drvdata(&wd_data->dev, wdd);
+	dev_set_name(&wd_data->dev, "watchdog%d", wdd->id);
+
 	kthread_init_work(&wd_data->work, watchdog_ping_work);
 	hrtimer_init(&wd_data->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	wd_data->timer.function = watchdog_timer_expired;
@@ -1014,15 +1026,6 @@ static int watchdog_cdev_register(struct watchdog_device *wdd)
 		}
 	}
 
-	device_initialize(&wd_data->dev);
-	wd_data->dev.devt = MKDEV(MAJOR(watchdog_devt), wdd->id);
-	wd_data->dev.class = &watchdog_class;
-	wd_data->dev.parent = wdd->parent;
-	wd_data->dev.groups = wdd->groups;
-	wd_data->dev.release = watchdog_core_data_release;
-	dev_set_drvdata(&wd_data->dev, wdd);
-	dev_set_name(&wd_data->dev, "watchdog%d", wdd->id);
-
 	/* Fill in the data structures */
 	cdev_init(&wd_data->cdev, &watchdog_fops);
 
@@ -1136,6 +1139,36 @@ void watchdog_dev_unregister(struct watchdog_device *wdd)
 }
 
 /*
+ *	watchdog_set_last_hw_keepalive: set last HW keepalive time for watchdog
+ *	@wdd: watchdog device
+ *	@last_ping_ms: time since last HW heartbeat
+ *
+ *	Adjusts the last known HW keepalive time for a watchdog timer.
+ *	This is needed if the watchdog is already running when the probe
+ *	function is called, and it can't be pinged immediately. This
+ *	function must be called immediately after watchdog registration,
+ *	and min_hw_heartbeat_ms must be set for this to be useful.
+ */
+int watchdog_set_last_hw_keepalive(struct watchdog_device *wdd,
+				   unsigned int last_ping_ms)
+{
+	struct watchdog_core_data *wd_data;
+	ktime_t now;
+
+	if (!wdd)
+		return -EINVAL;
+
+	wd_data = wdd->wd_data;
+
+	now = ktime_get();
+
+	wd_data->last_hw_keepalive = ktime_sub(now, ms_to_ktime(last_ping_ms));
+
+	return __watchdog_ping(wdd);
+}
+EXPORT_SYMBOL_GPL(watchdog_set_last_hw_keepalive);
+
+/*
  *	watchdog_dev_init: init dev part of watchdog core
  *
  *	Allocate a range of chardev nodes to use for watchdog devices