Initial pieces of WiFi HAL interface definition

Test: make -j48 android.hardware.wifi@1.0 android.hardware.wifi@1.0-java
Bug: 31350762
Change-Id: I1b598be397e08165fc9fd607888e064b139e8007
diff --git a/wifi/1.0/IWifiEventCallback.hal b/wifi/1.0/IWifiEventCallback.hal
new file mode 100644
index 0000000..84025ce
--- /dev/null
+++ b/wifi/1.0/IWifiEventCallback.hal
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware.wifi@1.0;
+
+interface IWifiEventCallback {
+  /**
+   * Called in response to a call to start indicating that the operation
+   * completed. After this callback the HAL must be fully operational.
+   */
+  oneway onStart();
+
+  /**
+   * Called in response to a call to start indicating that the operation
+   * failed. After this callback the HAL will be considered stopped. Another
+   * call to start will attempt to reinitialize the HAL; however, there is a
+   * chance it may fail again.
+   */
+  oneway onStartFailure(FailureReason reason);
+
+  /**
+   * Called in response to a call to stop indicating that the operation
+   * completed. When this event is received all IWifiChip objects retrieved
+   * after the last call to start will be considered invalid.
+   */
+  oneway onStop();
+
+  /**
+   * Called when the Wi-Fi system failed in a way that caused it be disabled.
+   * Calling start again must restart Wi-Fi as if stop then start was called
+   * (full state reset). When this event is received all IWifiChip objects
+   * retrieved after the last call to start will be considered invalid.
+   */
+  oneway onFailure(FailureReason reason);
+};