drivers/watchdog: make use of devm_register_reboot_notifier()

Save a bit of cleanup code by leveraging newly added
devm_register_reboot_notifier().

[akpm@linux-foundation.org: small cleanup: avoid 80-col tricks]
Link: http://lkml.kernel.org/r/20170411160615.9784-1-andrew.smirnov@gmail.com
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 32 insertions, 35 deletions

diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index 74265b2f806c..8a8d952f8df9 100644
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c
@@ -137,25 +137,6 @@ int watchdog_init_timeout(struct watchdog_device *wdd,
 }
 EXPORT_SYMBOL_GPL(watchdog_init_timeout);
 
-static int watchdog_reboot_notifier(struct notifier_block *nb,
-                                    unsigned long code, void *data)
-{
-        struct watchdog_device *wdd = container_of(nb, struct watchdog_device,
-                                                   reboot_nb);
-
-        if (code == SYS_DOWN || code == SYS_HALT) {
-                if (watchdog_active(wdd)) {
-                        int ret;
-
-                        ret = wdd->ops->stop(wdd);
-                        if (ret)
-                                return NOTIFY_BAD;
-                }
-        }
-
-        return NOTIFY_DONE;
-}
-
 static int watchdog_restart_notifier(struct notifier_block *nb,
                                      unsigned long action, void *data)
 {
@@ -244,19 +225,6 @@ static int __watchdog_register_device(struct watchdog_device *wdd)
                 }
         }
 
-        if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) {
-                wdd->reboot_nb.notifier_call = watchdog_reboot_notifier;
-
-                ret = register_reboot_notifier(&wdd->reboot_nb);
-                if (ret) {
-                        pr_err("watchdog%d: Cannot register reboot notifier (%d)\n",
-                               wdd->id, ret);
-                        watchdog_dev_unregister(wdd);
-                        ida_simple_remove(&watchdog_ida, wdd->id);
-                        return ret;
-                }
-        }
-
         if (wdd->ops->restart) {
                 wdd->restart_nb.notifier_call = watchdog_restart_notifier;
 
@@ -302,9 +270,6 @@ static void __watchdog_unregister_device(struct watchdog_device *wdd)
         if (wdd->ops->restart)
                 unregister_restart_handler(&wdd->restart_nb);
 
-        if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status))
-                unregister_reboot_notifier(&wdd->reboot_nb);
-
         watchdog_dev_unregister(wdd);
         ida_simple_remove(&watchdog_ida, wdd->id);
 }
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 0826e663bd5a..1e971a50d7fb 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -42,6 +42,7 @@
 #include <linux/miscdevice.h>   /* For handling misc devices */
 #include <linux/module.h>       /* For module stuff/... */
 #include <linux/mutex.h>        /* For mutexes */
+#include <linux/reboot.h>       /* For reboot notifier */
 #include <linux/slab.h>         /* For memory functions */
 #include <linux/types.h>        /* For standard types (like size_t) */
 #include <linux/watchdog.h>     /* For watchdog specific items */
@@ -1016,6 +1017,25 @@ static struct class watchdog_class = {
         .dev_groups =   wdt_groups,
 };
 
+static int watchdog_reboot_notifier(struct notifier_block *nb,
+                                    unsigned long code, void *data)
+{
+        struct watchdog_device *wdd;
+
+        wdd = container_of(nb, struct watchdog_device, reboot_nb);
+        if (code == SYS_DOWN || code == SYS_HALT) {
+                if (watchdog_active(wdd)) {
+                        int ret;
+
+                        ret = wdd->ops->stop(wdd);
+                        if (ret)
+                                return NOTIFY_BAD;
+                }
+        }
+
+        return NOTIFY_DONE;
+}
+
 /*
  *      watchdog_dev_register: register a watchdog device
  *      @wdd: watchdog device
@@ -1049,6 +1069,18 @@ int watchdog_dev_register(struct watchdog_device *wdd)
         if (ret) {
                 device_destroy(&watchdog_class, devno);
                 watchdog_cdev_unregister(wdd);
+                return ret;
+        }
+
+        if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) {
+                wdd->reboot_nb.notifier_call = watchdog_reboot_notifier;
+
+                ret = devm_register_reboot_notifier(dev, &wdd->reboot_nb);
+                if (ret) {
+                        pr_err("watchdog%d: Cannot register reboot notifier (%d)\n",
+                               wdd->id, ret);
+                        watchdog_dev_unregister(wdd);
+                }
         }
 
         return ret;