[PATCH v8 27/27] kernel/reboot: Add devm_register_restart_handler()

[Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>]

Add devm_register_restart_handler() helper that registers sys-off
handler using restart mode and with a default priority. Most drivers
will want to register restart handler with a default priority, so this
helper will reduce the boilerplate code and make code easier to read and
follow.

Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
 include/linux/reboot.h |  4 ++++
 kernel/reboot.c        | 22 ++++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index 7c6e1f308f7c..e5d9ef886179 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -145,6 +145,10 @@ int devm_register_power_off_handler(struct device *dev,
                                    int (*callback)(struct sys_off_data *data),
                                    void *cb_data);
 
+int devm_register_restart_handler(struct device *dev,
+                                 int (*callback)(struct sys_off_data *data),
+                                 void *cb_data);
+
 int register_platform_power_off(void (*power_off)(void));
 void unregister_platform_power_off(void (*power_off)(void));
 
diff --git a/kernel/reboot.c b/kernel/reboot.c
index b790025154ac..2e78bd754a75 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -484,6 +484,28 @@ int devm_register_power_off_handler(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_register_power_off_handler);
 
+/**
+ *     devm_register_restart_handler - Register restart handler
+ *     @dev: Device that registers callback
+ *     @callback: Callback function
+ *     @cb_data: Callback's argument
+ *
+ *     Registers resource-managed sys-off handler with a default priority
+ *     and using restart mode.
+ *
+ *     Returns zero on success, or error code on failure.
+ */
+int devm_register_restart_handler(struct device *dev,
+                                 int (*callback)(struct sys_off_data *data),
+                                 void *cb_data)
+{
+       return devm_register_sys_off_handler(dev,
+                                            SYS_OFF_MODE_RESTART,
+                                            SYS_OFF_PRIO_DEFAULT,
+                                            callback, cb_data);
+}
+EXPORT_SYMBOL_GPL(devm_register_restart_handler);
+
 static struct sys_off_handler *platform_power_off_handler;
 
 static int platform_power_off_notify(struct sys_off_data *data)
-- 
2.35.1