Input command can fail (with exceptions) if the touchscreen id is not 0

We had a device where the touchscreen was reconfigured during system
init, and as a result was assigned a device id that was not 0.
The following message from InputReader.cpp was logged when this occured:
I/InputReader(  762): Device reconfigured: id=4, name='himax-touchscreen', size 1024x600, orientation 1, mode 1, display id 0

Attempting to use the input command for the touchscreen in this state
will fail due to the hardcoded touchscreen device id.

Change-Id: I4e8fad864e7b83cce00c680b254bad06e1200f15

1 files changed, 14 insertions, 3 deletions

diff --git a/cmds/input/src/com/android/commands/input/Input.java b/cmds/input/src/com/android/commands/input/Input.java
index 2a7c79bdfb5b..754d3f510bbd 100644
--- a/cmds/input/src/com/android/commands/input/Input.java
+++ b/cmds/input/src/com/android/commands/input/Input.java
@@ -234,6 +234,18 @@ public class Input {
                 InputManager.INJECT_INPUT_EVENT_MODE_WAIT_FOR_FINISH);
     }
 
+    private int getInputDeviceId(int inputSource) {
+        final int DEFAULT_DEVICE_ID = 0;
+        int[] devIds = InputDevice.getDeviceIds();
+        for (int devId : devIds) {
+            InputDevice inputDev = InputDevice.getDevice(devId);
+            if (inputDev.supportsSource(inputSource)) {
+                return devId;
+            }
+        }
+        return DEFAULT_DEVICE_ID;
+    }
+
     /**
      * Builds a MotionEvent and injects it into the event stream.
      *
@@ -249,11 +261,10 @@ public class Input {
         final int DEFAULT_META_STATE = 0;
         final float DEFAULT_PRECISION_X = 1.0f;
         final float DEFAULT_PRECISION_Y = 1.0f;
-        final int DEFAULT_DEVICE_ID = 0;
         final int DEFAULT_EDGE_FLAGS = 0;
         MotionEvent event = MotionEvent.obtain(when, when, action, x, y, pressure, DEFAULT_SIZE,
-                DEFAULT_META_STATE, DEFAULT_PRECISION_X, DEFAULT_PRECISION_Y, DEFAULT_DEVICE_ID,
-                DEFAULT_EDGE_FLAGS);
+                DEFAULT_META_STATE, DEFAULT_PRECISION_X, DEFAULT_PRECISION_Y,
+                getInputDeviceId(inputSource), DEFAULT_EDGE_FLAGS);
         event.setSource(inputSource);
         Log.i(TAG, "injectMotionEvent: " + event);
         InputManager.getInstance().injectInputEvent(event,