UsbService: Make USB disconnect handling for accessory mode more robust

Handle the case where the kernel driver is in accessory mode but we failed
to initialize it at the framework level.  On disconnnect, check to see if the
accessory kernel driver is enabled rather than checking mCurrentAccessory.
That way we will restore the USB state in the kernel even if mCurrentAccessory
is null.

Change-Id: I35d458f21a8b21611946da523d0f53723cab0540
Signed-off-by: Mike Lockwood <lockwood@android.com>

1 files changed, 11 insertions, 6 deletions

diff --git a/services/java/com/android/server/usb/UsbService.java b/services/java/com/android/server/usb/UsbService.java
index b7f6346..a151af0 100644
--- a/services/java/com/android/server/usb/UsbService.java
+++ b/services/java/com/android/server/usb/UsbService.java
@@ -561,11 +561,14 @@ public class UsbService extends IUsbManager.Stub {
                     case MSG_UPDATE_STATE:
                         if (mConnected != mLastConnected || mConfiguration != mLastConfiguration) {
                             if (mConnected == 0) {
-                                // make sure accessory mode is off, and restore default functions
-                                if (mCurrentAccessory != null && UsbManager.setFunctionEnabled(
-                                        UsbManager.USB_FUNCTION_ACCESSORY, false)) {
+                                if (UsbManager.isFunctionEnabled(
+                                            UsbManager.USB_FUNCTION_ACCESSORY)) {
+                                    // make sure accessory mode is off, and restore default functions
                                     Log.d(TAG, "exited USB accessory mode");
-
+                                    if (!UsbManager.setFunctionEnabled
+                                            (UsbManager.USB_FUNCTION_ACCESSORY, false)) {
+                                        Log.e(TAG, "could not disable accessory function");
+                                    }
                                     int count = mDefaultFunctions.size();
                                     for (int i = 0; i < count; i++) {
                                         String function = mDefaultFunctions.get(i);
@@ -574,8 +577,10 @@ public class UsbService extends IUsbManager.Stub {
                                         }
                                     }
 
-                                    mDeviceManager.accessoryDetached(mCurrentAccessory);
-                                    mCurrentAccessory = null;
+                                    if (mCurrentAccessory != null) {
+                                        mDeviceManager.accessoryDetached(mCurrentAccessory);
+                                        mCurrentAccessory = null;
+                                    }
                                 }
                             }