From 541295a9a53e38bde5fea4223ed2d63e3aacf93b Mon Sep 17 00:00:00 2001
From: Jerry Zhang <zhangjerry@google.com>
Date: Wed, 12 Oct 2016 18:04:03 -0700
Subject: [PATCH] Fixed handling of usb state during adb changes.

When changing state to adb from mtp (charging), we want to disable
the old mtp function. Similarly when change to away from adb to
charging, enable the mtp function.

Also the mtp function should never be persisted.

Bug: 31818377
Bug: 31814300
Test: Manually verify that the correct usb configuration is displayed.
Test: Manually verify that logcat is not kicked during boot.
Change-Id: Idcb7f53be39ea38712d5de45b323d8daeb552129
(cherry-picked from commit 58018d01a3c384b954275d15bee7f9c52a1c7c0a)
---
 .../android/server/usb/UsbDeviceManager.java  | 34 ++++++++++---------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/services/usb/java/com/android/server/usb/UsbDeviceManager.java b/services/usb/java/com/android/server/usb/UsbDeviceManager.java
index 8560651fa7ec5..2132cd317b438 100644
--- a/services/usb/java/com/android/server/usb/UsbDeviceManager.java
+++ b/services/usb/java/com/android/server/usb/UsbDeviceManager.java
@@ -337,13 +337,11 @@ public class UsbDeviceManager {
                 // Restore default functions.
                 mCurrentFunctions = SystemProperties.get(USB_CONFIG_PROPERTY,
                         UsbManager.USB_FUNCTION_NONE);
-                if (UsbManager.USB_FUNCTION_NONE.equals(mCurrentFunctions)) {
-                    mCurrentFunctions = UsbManager.USB_FUNCTION_MTP;
-                }
                 mCurrentFunctionsApplied = mCurrentFunctions.equals(
                         SystemProperties.get(USB_STATE_PROPERTY));
                 mAdbEnabled = UsbManager.containsFunction(getDefaultFunctions(),
                         UsbManager.USB_FUNCTION_ADB);
+
                 setEnabledFunctions(null, false);
 
                 String state = FileUtils.readTextFile(new File(STATE_PATH), 0, null).trim();
@@ -452,17 +450,24 @@ public class UsbDeviceManager {
             if (DEBUG) Slog.d(TAG, "setAdbEnabled: " + enable);
             if (enable != mAdbEnabled) {
                 mAdbEnabled = enable;
+                String oldFunctions = mCurrentFunctions;
 
-                // Due to the persist.sys.usb.config property trigger, changing adb state requires
-                // persisting default function
-                String oldFunctions = getDefaultFunctions();
-                String newFunctions = applyAdbFunction(oldFunctions);
-                if (!oldFunctions.equals(newFunctions)) {
-                    SystemProperties.set(USB_PERSISTENT_CONFIG_PROPERTY, newFunctions);
+                // Persist the adb setting
+                String newFunction = applyAdbFunction(SystemProperties.get(
+                            USB_PERSISTENT_CONFIG_PROPERTY, UsbManager.USB_FUNCTION_NONE));
+                SystemProperties.set(USB_PERSISTENT_CONFIG_PROPERTY, newFunction);
+
+                // Changing the persistent config also changes the normal
+                // config. Wait for this to happen before changing again.
+                waitForState(newFunction);
+
+                // Remove mtp from the config if file transfer is not enabled
+                if (oldFunctions.equals(UsbManager.USB_FUNCTION_MTP) &&
+                        !mUsbDataUnlocked && enable) {
+                    oldFunctions = UsbManager.USB_FUNCTION_NONE;
                 }
 
-                // After persisting them use the lock-down aware function set
-                setEnabledFunctions(mCurrentFunctions, false);
+                setEnabledFunctions(oldFunctions, false);
                 updateAdbNotification();
             }
 
@@ -514,7 +519,8 @@ public class UsbDeviceManager {
         }
 
         private boolean trySetEnabledFunctions(String functions, boolean forceRestart) {
-            if (functions == null) {
+            if (functions == null || applyAdbFunction(functions)
+                    .equals(UsbManager.USB_FUNCTION_NONE)) {
                 functions = getDefaultFunctions();
             }
             functions = applyAdbFunction(functions);
@@ -596,10 +602,6 @@ public class UsbDeviceManager {
             if (mBroadcastedIntent == null) {
                 for (String key : keySet) {
                     if (intent.getBooleanExtra(key, false)) {
-                        // MTP function is enabled by default.
-                        if (UsbManager.USB_FUNCTION_MTP.equals(key)) {
-                            continue;
-                        }
                         return true;
                     }
                 }