Add dbus interface for watchdog

Add a generic interface for watchdog, for system state monitoring.

Partially resolves: openbmc/openbmc#767

Change-Id: I7f04fe9e8a35669612501b05a1a06e03e9928194
Signed-off-by: Yi Li <adamliyi@msn.com>
diff --git a/xyz/openbmc_project/State/Watchdog.interface.yaml b/xyz/openbmc_project/State/Watchdog.interface.yaml
new file mode 100644
index 0000000..80da655
--- /dev/null
+++ b/xyz/openbmc_project/State/Watchdog.interface.yaml
@@ -0,0 +1,25 @@
+description: >
+    Implement the watchdog function.
+properties:
+    - name: Enabled
+      type: boolean
+      description: >
+          The watchdog is enabled or not.
+      default: false
+    - name: Interval
+      type: uint64
+      description: >
+          Time interval to arm the watchdog, in mili-second.
+      default: 30000
+    - name: TimeRemaining
+      type: uint64
+      description: >
+          Time remaining before timeout, in mili-second.
+          Setting this property can re-arm the watchdog.
+      default: 0
+signals:
+    - name: Timeout
+      description: >
+          Signal indicating that watchdog timed out.
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4