1 files changed, 45 insertions, 0 deletions

diff --git a/kernel/power/poweroff.c b/kernel/power/poweroff.c
new file mode 100644
index 000000000000..715081b2d829
--- /dev/null
+++ b/kernel/power/poweroff.c
@@ -0,0 +1,45 @@
+/*
+ * poweroff.c - sysrq handler to gracefully power down machine.
+ *
+ * This file is released under the GPL v2
+ */
+
+#include <linux/kernel.h>
+#include <linux/sysrq.h>
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/workqueue.h>
+
+/*
+ * When the user hits Sys-Rq o to power down the machine this is the
+ * callback we use.
+ */
+
+static void do_poweroff(void *dummy)
+{
+        if (pm_power_off)
+                pm_power_off();
+}
+
+static DECLARE_WORK(poweroff_work, do_poweroff, NULL);
+
+static void handle_poweroff(int key, struct pt_regs *pt_regs,
+                                struct tty_struct *tty)
+{
+        schedule_work(&poweroff_work);
+}
+
+static struct sysrq_key_op      sysrq_poweroff_op = {
+        .handler        = handle_poweroff,
+        .help_msg       = "powerOff",
+        .action_msg     = "Power Off",
+        .enable_mask    = SYSRQ_ENABLE_BOOT,
+};
+
+static int pm_sysrq_init(void)
+{
+        register_sysrq_key('o', &sysrq_poweroff_op);
+        return 0;
+}
+
+subsys_initcall(pm_sysrq_init);