From 1bec44836ed6b29e128849b7be34dc7b2a214e76 Mon Sep 17 00:00:00 2001
From: Jeff Sharkey <jsharkey@android.com>
Date: Thu, 23 Feb 2017 12:40:54 -0700
Subject: [PATCH] Take another pass at detecting USB connections.

For some odd reason, devices with ADB connections in test harnesses
are reporting that they're connected over an AC charger instead of
USB charger.

So switch to reading a sysfs file to detect an active USB connection.

Test: builds, boots, rescue disabled when USB connection present
Bug: 34872406
Change-Id: I4c2cb9ed7e51b9692ce81eb0ef4945dae0036212
---
 .../java/com/android/server/RescueParty.java  | 35 ++++---------------
 1 file changed, 6 insertions(+), 29 deletions(-)

diff --git a/services/core/java/com/android/server/RescueParty.java b/services/core/java/com/android/server/RescueParty.java
index 33351ffc0f77a..480b08a77cf79 100644
--- a/services/core/java/com/android/server/RescueParty.java
+++ b/services/core/java/com/android/server/RescueParty.java
@@ -19,13 +19,9 @@ package com.android.server;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.pm.UserInfo;
-import android.os.BatteryManager;
-import android.os.BatteryProperties;
 import android.os.Build;
-import android.os.IBatteryPropertiesListener;
-import android.os.IBatteryPropertiesRegistrar;
+import android.os.FileUtils;
 import android.os.RecoverySystem;
-import android.os.ServiceManager;
 import android.os.SystemClock;
 import android.os.SystemProperties;
 import android.os.UserHandle;
@@ -34,14 +30,12 @@ import android.provider.Settings;
 import android.text.format.DateUtils;
 import android.util.ExceptionUtils;
 import android.util.MathUtils;
-import android.util.MutableBoolean;
 import android.util.Slog;
 import android.util.SparseArray;
 
 import com.android.internal.util.ArrayUtils;
 
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.TimeUnit;
+import java.io.File;
 
 /**
  * Utilities to help rescue the system from crash loops. Callers are expected to
@@ -325,30 +319,13 @@ public class RescueParty {
 
     /**
      * Hacky test to check if the device has an active USB connection, which is
-     * a good proxy for someone doing local development work. It uses a low
-     * level call since we may not have started {@link BatteryManager} yet.
+     * a good proxy for someone doing local development work.
      */
     private static boolean isUsbActive() {
-        final MutableBoolean res = new MutableBoolean(false);
-        final CountDownLatch latch = new CountDownLatch(1);
-        final IBatteryPropertiesListener listener = new IBatteryPropertiesListener.Stub() {
-            @Override
-            public void batteryPropertiesChanged(BatteryProperties props) {
-                res.value = props.chargerUsbOnline;
-                latch.countDown();
-            }
-        };
-
         try {
-            final IBatteryPropertiesRegistrar bpr = IBatteryPropertiesRegistrar.Stub
-                    .asInterface(ServiceManager.getService("batteryproperties"));
-            bpr.registerListener(listener);
-            try {
-                latch.await(5, TimeUnit.SECONDS);
-            } finally {
-                bpr.unregisterListener(listener);
-            }
-            return res.value;
+            final String state = FileUtils
+                    .readTextFile(new File("/sys/class/android_usb/android0/state"), 128, "");
+            return "CONFIGURED".equals(state.trim());
         } catch (Throwable t) {
             Slog.w(TAG, "Failed to determine if device was on USB", t);
             return false;