Merge pull request #13260 from JosJuice/android-gcadapter-hotplug-callback

Android: Detect GCAdapter hotplug using BroadcastReceiver

6 files changed, 342 insertions, 233 deletions

diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/DolphinApplication.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/DolphinApplication.java
index 8ff78ebb0e..91200852a1 100644
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/DolphinApplication.java
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/DolphinApplication.java
@@ -9,8 +9,8 @@ import android.hardware.usb.UsbManager;
 
 import org.dolphinemu.dolphinemu.utils.ActivityTracker;
 import org.dolphinemu.dolphinemu.utils.DirectoryInitialization;
-import org.dolphinemu.dolphinemu.utils.Java_GCAdapter;
-import org.dolphinemu.dolphinemu.utils.Java_WiimoteAdapter;
+import org.dolphinemu.dolphinemu.utils.GCAdapter;
+import org.dolphinemu.dolphinemu.utils.WiimoteAdapter;
 import org.dolphinemu.dolphinemu.utils.VolleyUtil;
 
 public class DolphinApplication extends Application
@@ -28,8 +28,8 @@ public class DolphinApplication extends Application
     VolleyUtil.init(getApplicationContext());
     System.loadLibrary("main");
 
-    Java_GCAdapter.manager = (UsbManager) getSystemService(Context.USB_SERVICE);
-    Java_WiimoteAdapter.manager = (UsbManager) getSystemService(Context.USB_SERVICE);
+    GCAdapter.manager = (UsbManager) getSystemService(Context.USB_SERVICE);
+    WiimoteAdapter.manager = (UsbManager) getSystemService(Context.USB_SERVICE);
 
     if (DirectoryInitialization.shouldStart(getApplicationContext()))
       DirectoryInitialization.start(getApplicationContext());
diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/GCAdapter.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/GCAdapter.java
new file mode 100644
index 0000000000..b9e67e654f
--- /dev/null
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/GCAdapter.java
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package org.dolphinemu.dolphinemu.utils;
+
+import android.app.PendingIntent;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.hardware.usb.UsbConfiguration;
+import android.hardware.usb.UsbConstants;
+import android.hardware.usb.UsbDevice;
+import android.hardware.usb.UsbDeviceConnection;
+import android.hardware.usb.UsbEndpoint;
+import android.hardware.usb.UsbInterface;
+import android.hardware.usb.UsbManager;
+import android.os.Build;
+import android.widget.Toast;
+
+import androidx.annotation.Keep;
+import androidx.annotation.Nullable;
+import androidx.core.content.ContextCompat;
+
+import org.dolphinemu.dolphinemu.BuildConfig;
+import org.dolphinemu.dolphinemu.DolphinApplication;
+import org.dolphinemu.dolphinemu.R;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class GCAdapter
+{
+  public static UsbManager manager;
+
+  @Keep
+  static byte[] controllerPayload = new byte[37];
+
+  static UsbDeviceConnection usbConnection;
+  static UsbInterface usbInterface;
+  static UsbEndpoint usbIn;
+  static UsbEndpoint usbOut;
+
+  private static final String ACTION_GC_ADAPTER_PERMISSION_GRANTED =
+          BuildConfig.APPLICATION_ID + ".GC_ADAPTER_PERMISSION_GRANTED";
+
+  private static final Object hotplugCallbackLock = new Object();
+  private static boolean hotplugCallbackEnabled = false;
+  private static UsbDevice adapterDevice = null;
+  private static BroadcastReceiver hotplugBroadcastReceiver = new BroadcastReceiver()
+  {
+    @Override
+    public void onReceive(Context context, Intent intent)
+    {
+      onUsbDevicesChanged();
+    }
+  };
+
+  private static void requestPermission()
+  {
+    HashMap<String, UsbDevice> devices = manager.getDeviceList();
+    for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
+    {
+      UsbDevice dev = pair.getValue();
+      if (dev.getProductId() == 0x0337 && dev.getVendorId() == 0x057e)
+      {
+        if (!manager.hasPermission(dev))
+        {
+          Context context = DolphinApplication.getAppContext();
+
+          int flags = Build.VERSION.SDK_INT >= Build.VERSION_CODES.M ?
+                  PendingIntent.FLAG_IMMUTABLE : 0;
+          PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0,
+                  new Intent(ACTION_GC_ADAPTER_PERMISSION_GRANTED), flags);
+
+          manager.requestPermission(dev, pendingIntent);
+        }
+      }
+    }
+  }
+
+  public static void shutdown()
+  {
+    usbConnection.close();
+  }
+
+  @Keep
+  public static int getFd()
+  {
+    return usbConnection.getFileDescriptor();
+  }
+
+  @Keep
+  public static boolean isUsbDeviceAvailable()
+  {
+    synchronized (hotplugCallbackLock)
+    {
+      return adapterDevice != null;
+    }
+  }
+
+  @Nullable
+  private static UsbDevice queryAdapter()
+  {
+    HashMap<String, UsbDevice> devices = manager.getDeviceList();
+    for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
+    {
+      UsbDevice dev = pair.getValue();
+      if (dev.getProductId() == 0x0337 && dev.getVendorId() == 0x057e)
+      {
+        if (manager.hasPermission(dev))
+          return dev;
+        else
+          requestPermission();
+      }
+    }
+    return null;
+  }
+
+  public static void initAdapter()
+  {
+    byte[] init = {0x13};
+    usbConnection.bulkTransfer(usbOut, init, init.length, 0);
+  }
+
+  @Keep
+  public static int input()
+  {
+    return usbConnection.bulkTransfer(usbIn, controllerPayload, controllerPayload.length, 16);
+  }
+
+  @Keep
+  public static int output(byte[] rumble)
+  {
+    return usbConnection.bulkTransfer(usbOut, rumble, 5, 16);
+  }
+
+  @Keep
+  public static boolean openAdapter()
+  {
+    UsbDevice dev;
+    synchronized (hotplugCallbackLock)
+    {
+      dev = adapterDevice;
+    }
+    if (dev == null)
+    {
+      return false;
+    }
+
+    usbConnection = manager.openDevice(dev);
+    if (usbConnection == null)
+    {
+      return false;
+    }
+
+    Log.info("GCAdapter: Number of configurations: " + dev.getConfigurationCount());
+    Log.info("GCAdapter: Number of interfaces: " + dev.getInterfaceCount());
+
+    if (dev.getConfigurationCount() > 0 && dev.getInterfaceCount() > 0)
+    {
+      UsbConfiguration conf = dev.getConfiguration(0);
+      usbInterface = conf.getInterface(0);
+      usbConnection.claimInterface(usbInterface, true);
+
+      Log.info("GCAdapter: Number of endpoints: " + usbInterface.getEndpointCount());
+
+      if (usbInterface.getEndpointCount() == 2)
+      {
+        for (int i = 0; i < usbInterface.getEndpointCount(); ++i)
+          if (usbInterface.getEndpoint(i).getDirection() == UsbConstants.USB_DIR_IN)
+            usbIn = usbInterface.getEndpoint(i);
+          else
+            usbOut = usbInterface.getEndpoint(i);
+
+        initAdapter();
+        return true;
+      }
+      else
+      {
+        usbConnection.releaseInterface(usbInterface);
+      }
+    }
+
+    Toast.makeText(DolphinApplication.getAppContext(), R.string.replug_gc_adapter,
+            Toast.LENGTH_LONG).show();
+    usbConnection.close();
+    return false;
+  }
+
+  @Keep
+  public static void enableHotplugCallback()
+  {
+    synchronized (hotplugCallbackLock)
+    {
+      if (hotplugCallbackEnabled)
+      {
+        throw new IllegalStateException("enableHotplugCallback was called when already enabled");
+      }
+
+      IntentFilter filter = new IntentFilter();
+      filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
+      filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
+      filter.addAction(ACTION_GC_ADAPTER_PERMISSION_GRANTED);
+
+      ContextCompat.registerReceiver(DolphinApplication.getAppContext(), hotplugBroadcastReceiver,
+              filter, ContextCompat.RECEIVER_EXPORTED);
+
+      hotplugCallbackEnabled = true;
+
+      onUsbDevicesChanged();
+    }
+  }
+
+  @Keep
+  public static void disableHotplugCallback()
+  {
+    synchronized (hotplugCallbackLock)
+    {
+      if (hotplugCallbackEnabled)
+      {
+        DolphinApplication.getAppContext().unregisterReceiver(hotplugBroadcastReceiver);
+        hotplugCallbackEnabled = false;
+        adapterDevice = null;
+      }
+    }
+  }
+
+  public static void onUsbDevicesChanged()
+  {
+    synchronized (hotplugCallbackLock)
+    {
+      if (adapterDevice != null)
+      {
+        boolean adapterStillConnected = manager.getDeviceList().entrySet().stream()
+                .anyMatch(pair -> pair.getValue().getDeviceId() == adapterDevice.getDeviceId());
+
+        if (!adapterStillConnected)
+        {
+          adapterDevice = null;
+          onAdapterDisconnected();
+        }
+      }
+
+      if (adapterDevice == null)
+      {
+        UsbDevice newAdapter = queryAdapter();
+        if (newAdapter != null)
+        {
+          adapterDevice = newAdapter;
+          onAdapterConnected();
+        }
+      }
+    }
+  }
+
+  private static native void onAdapterConnected();
+
+  private static native void onAdapterDisconnected();
+}
diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/Java_GCAdapter.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/Java_GCAdapter.java
deleted file mode 100644
index 3fcd58afac..0000000000
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/Java_GCAdapter.java
+++ /dev/null
@@ -1,158 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-package org.dolphinemu.dolphinemu.utils;
-
-import android.app.PendingIntent;
-import android.content.Context;
-import android.content.Intent;
-import android.hardware.usb.UsbConfiguration;
-import android.hardware.usb.UsbConstants;
-import android.hardware.usb.UsbDevice;
-import android.hardware.usb.UsbDeviceConnection;
-import android.hardware.usb.UsbEndpoint;
-import android.hardware.usb.UsbInterface;
-import android.hardware.usb.UsbManager;
-import android.os.Build;
-import android.widget.Toast;
-
-import androidx.annotation.Keep;
-
-import org.dolphinemu.dolphinemu.DolphinApplication;
-import org.dolphinemu.dolphinemu.R;
-import org.dolphinemu.dolphinemu.services.USBPermService;
-
-import java.util.HashMap;
-import java.util.Map;
-
-public class Java_GCAdapter
-{
-  public static UsbManager manager;
-
-  @Keep
-  static byte[] controller_payload = new byte[37];
-
-  static UsbDeviceConnection usb_con;
-  static UsbInterface usb_intf;
-  static UsbEndpoint usb_in;
-  static UsbEndpoint usb_out;
-
-  private static void RequestPermission()
-  {
-    HashMap<String, UsbDevice> devices = manager.getDeviceList();
-    for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
-    {
-      UsbDevice dev = pair.getValue();
-      if (dev.getProductId() == 0x0337 && dev.getVendorId() == 0x057e)
-      {
-        if (!manager.hasPermission(dev))
-        {
-          Context context = DolphinApplication.getAppContext();
-          Intent intent = new Intent(context, USBPermService.class);
-
-          int flags = Build.VERSION.SDK_INT >= Build.VERSION_CODES.M ?
-                  PendingIntent.FLAG_IMMUTABLE : 0;
-          PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, flags);
-
-          manager.requestPermission(dev, pendingIntent);
-        }
-      }
-    }
-  }
-
-  public static void Shutdown()
-  {
-    usb_con.close();
-  }
-
-  @Keep
-  public static int GetFD()
-  {
-    return usb_con.getFileDescriptor();
-  }
-
-  @Keep
-  public static boolean QueryAdapter()
-  {
-    HashMap<String, UsbDevice> devices = manager.getDeviceList();
-    for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
-    {
-      UsbDevice dev = pair.getValue();
-      if (dev.getProductId() == 0x0337 && dev.getVendorId() == 0x057e)
-      {
-        if (manager.hasPermission(dev))
-          return true;
-        else
-          RequestPermission();
-      }
-    }
-    return false;
-  }
-
-  public static void InitAdapter()
-  {
-    byte[] init = {0x13};
-    usb_con.bulkTransfer(usb_out, init, init.length, 0);
-  }
-
-  @Keep
-  public static int Input()
-  {
-    return usb_con.bulkTransfer(usb_in, controller_payload, controller_payload.length, 16);
-  }
-
-  @Keep
-  public static int Output(byte[] rumble)
-  {
-    return usb_con.bulkTransfer(usb_out, rumble, 5, 16);
-  }
-
-  @Keep
-  public static boolean OpenAdapter()
-  {
-    HashMap<String, UsbDevice> devices = manager.getDeviceList();
-    for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
-    {
-      UsbDevice dev = pair.getValue();
-      if (dev.getProductId() == 0x0337 && dev.getVendorId() == 0x057e)
-      {
-        if (manager.hasPermission(dev))
-        {
-          usb_con = manager.openDevice(dev);
-
-          Log.info("GCAdapter: Number of configurations: " + dev.getConfigurationCount());
-          Log.info("GCAdapter: Number of interfaces: " + dev.getInterfaceCount());
-
-          if (dev.getConfigurationCount() > 0 && dev.getInterfaceCount() > 0)
-          {
-            UsbConfiguration conf = dev.getConfiguration(0);
-            usb_intf = conf.getInterface(0);
-            usb_con.claimInterface(usb_intf, true);
-
-            Log.info("GCAdapter: Number of endpoints: " + usb_intf.getEndpointCount());
-
-            if (usb_intf.getEndpointCount() == 2)
-            {
-              for (int i = 0; i < usb_intf.getEndpointCount(); ++i)
-                if (usb_intf.getEndpoint(i).getDirection() == UsbConstants.USB_DIR_IN)
-                  usb_in = usb_intf.getEndpoint(i);
-                else
-                  usb_out = usb_intf.getEndpoint(i);
-
-              InitAdapter();
-              return true;
-            }
-            else
-            {
-              usb_con.releaseInterface(usb_intf);
-            }
-          }
-
-          Toast.makeText(DolphinApplication.getAppContext(), R.string.replug_gc_adapter,
-                  Toast.LENGTH_LONG).show();
-          usb_con.close();
-        }
-      }
-    }
-    return false;
-  }
-}
diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/Java_WiimoteAdapter.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/WiimoteAdapter.java
index 469375614f..98a7d51900 100644
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/Java_WiimoteAdapter.java
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/utils/WiimoteAdapter.java
@@ -22,7 +22,7 @@ import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 
-public class Java_WiimoteAdapter
+public class WiimoteAdapter
 {
   final static int MAX_PAYLOAD = 23;
   final static int MAX_WIIMOTES = 4;
@@ -31,14 +31,14 @@ public class Java_WiimoteAdapter
   final static short NINTENDO_WIIMOTE_PRODUCT_ID = 0x0306;
   public static UsbManager manager;
 
-  static UsbDeviceConnection usb_con;
-  static UsbInterface[] usb_intf = new UsbInterface[MAX_WIIMOTES];
-  static UsbEndpoint[] usb_in = new UsbEndpoint[MAX_WIIMOTES];
+  static UsbDeviceConnection usbConnection;
+  static UsbInterface[] usbInterface = new UsbInterface[MAX_WIIMOTES];
+  static UsbEndpoint[] usbIn = new UsbEndpoint[MAX_WIIMOTES];
 
   @Keep
-  public static byte[][] wiimote_payload = new byte[MAX_WIIMOTES][MAX_PAYLOAD];
+  public static byte[][] wiimotePayload = new byte[MAX_WIIMOTES][MAX_PAYLOAD];
 
-  private static void RequestPermission()
+  private static void requestPermission()
   {
     HashMap<String, UsbDevice> devices = manager.getDeviceList();
     for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
@@ -65,7 +65,7 @@ public class Java_WiimoteAdapter
   }
 
   @Keep
-  public static boolean QueryAdapter()
+  public static boolean queryAdapter()
   {
     HashMap<String, UsbDevice> devices = manager.getDeviceList();
     for (Map.Entry<String, UsbDevice> pair : devices.entrySet())
@@ -77,20 +77,20 @@ public class Java_WiimoteAdapter
         if (manager.hasPermission(dev))
           return true;
         else
-          RequestPermission();
+          requestPermission();
       }
     }
     return false;
   }
 
   @Keep
-  public static int Input(int index)
+  public static int input(int index)
   {
-    return usb_con.bulkTransfer(usb_in[index], wiimote_payload[index], MAX_PAYLOAD, TIMEOUT);
+    return usbConnection.bulkTransfer(usbIn[index], wiimotePayload[index], MAX_PAYLOAD, TIMEOUT);
   }
 
   @Keep
-  public static int Output(int index, byte[] buf, int size)
+  public static int output(int index, byte[] buf, int size)
   {
     byte report_number = buf[0];
 
@@ -105,7 +105,7 @@ public class Java_WiimoteAdapter
     final int HID_SET_REPORT = 0x9;
     final int HID_OUTPUT = (2 << 8);
 
-    int write = usb_con.controlTransfer(
+    int write = usbConnection.controlTransfer(
             LIBUSB_REQUEST_TYPE_CLASS | LIBUSB_RECIPIENT_INTERFACE | LIBUSB_ENDPOINT_OUT,
             HID_SET_REPORT,
             HID_OUTPUT | report_number,
@@ -120,10 +120,10 @@ public class Java_WiimoteAdapter
   }
 
   @Keep
-  public static boolean OpenAdapter()
+  public static boolean openAdapter()
   {
     // If the adapter is already open. Don't attempt to do it again
-    if (usb_con != null && usb_con.getFileDescriptor() != -1)
+    if (usbConnection != null && usbConnection.getFileDescriptor() != -1)
       return true;
 
     HashMap<String, UsbDevice> devices = manager.getDeviceList();
@@ -135,7 +135,7 @@ public class Java_WiimoteAdapter
       {
         if (manager.hasPermission(dev))
         {
-          usb_con = manager.openDevice(dev);
+          usbConnection = manager.openDevice(dev);
           UsbConfiguration conf = dev.getConfiguration(0);
 
           Log.info("Number of configurations: " + dev.getConfigurationCount());
@@ -149,20 +149,20 @@ public class Java_WiimoteAdapter
             for (int i = 0; i < MAX_WIIMOTES; ++i)
             {
               // One interface per Wii Remote
-              usb_intf[i] = dev.getInterface(i);
-              usb_con.claimInterface(usb_intf[i], true);
+              usbInterface[i] = dev.getInterface(i);
+              usbConnection.claimInterface(usbInterface[i], true);
 
               // One endpoint per Wii Remote. Input only
               // Output reports go through the control channel.
-              usb_in[i] = usb_intf[i].getEndpoint(0);
-              Log.info("Interface " + i + " endpoint count:" + usb_intf[i].getEndpointCount());
+              usbIn[i] = usbInterface[i].getEndpoint(0);
+              Log.info("Interface " + i + " endpoint count:" + usbInterface[i].getEndpointCount());
             }
             return true;
           }
           else
           {
             // XXX: Message that the device was found, but it needs to be unplugged and plugged back in?
-            usb_con.close();
+            usbConnection.close();
           }
         }
       }
diff --git a/Source/Core/Core/HW/WiimoteReal/IOAndroid.cpp b/Source/Core/Core/HW/WiimoteReal/IOAndroid.cpp
index 10234ceef7..507cacf006 100644
--- a/Source/Core/Core/HW/WiimoteReal/IOAndroid.cpp
+++ b/Source/Core/Core/HW/WiimoteReal/IOAndroid.cpp
@@ -30,8 +30,8 @@ void WiimoteScannerAndroid::FindWiimotes(std::vector<Wiimote*>& found_wiimotes,
 
   JNIEnv* env = IDCache::GetEnvForThread();
 
-  jmethodID openadapter_func = env->GetStaticMethodID(s_adapter_class, "OpenAdapter", "()Z");
-  jmethodID queryadapter_func = env->GetStaticMethodID(s_adapter_class, "QueryAdapter", "()Z");
+  jmethodID openadapter_func = env->GetStaticMethodID(s_adapter_class, "openAdapter", "()Z");
+  jmethodID queryadapter_func = env->GetStaticMethodID(s_adapter_class, "queryAdapter", "()Z");
 
   if (env->CallStaticBooleanMethod(s_adapter_class, queryadapter_func) &&
       env->CallStaticBooleanMethod(s_adapter_class, openadapter_func))
@@ -55,15 +55,15 @@ bool WiimoteAndroid::ConnectInternal()
 {
   m_env = IDCache::GetEnvForThread();
 
-  jfieldID payload_field = m_env->GetStaticFieldID(s_adapter_class, "wiimote_payload", "[[B");
+  jfieldID payload_field = m_env->GetStaticFieldID(s_adapter_class, "wiimotePayload", "[[B");
   jobjectArray payload_object =
       reinterpret_cast<jobjectArray>(m_env->GetStaticObjectField(s_adapter_class, payload_field));
   m_java_wiimote_payload =
       (jbyteArray)m_env->GetObjectArrayElement(payload_object, m_mayflash_index);
 
   // Get function pointers
-  m_input_func = m_env->GetStaticMethodID(s_adapter_class, "Input", "(I)I");
-  m_output_func = m_env->GetStaticMethodID(s_adapter_class, "Output", "(I[BI)I");
+  m_input_func = m_env->GetStaticMethodID(s_adapter_class, "input", "(I)I");
+  m_output_func = m_env->GetStaticMethodID(s_adapter_class, "output", "(I[BI)I");
 
   is_connected = true;
 
@@ -110,7 +110,7 @@ int WiimoteAndroid::IOWrite(u8 const* buf, size_t len)
 void InitAdapterClass()
 {
   JNIEnv* env = IDCache::GetEnvForThread();
-  jclass adapter_class = env->FindClass("org/dolphinemu/dolphinemu/utils/Java_WiimoteAdapter");
+  jclass adapter_class = env->FindClass("org/dolphinemu/dolphinemu/utils/WiimoteAdapter");
   s_adapter_class = reinterpret_cast<jclass>(env->NewGlobalRef(adapter_class));
 }
 }  // namespace WiimoteReal
diff --git a/Source/Core/InputCommon/GCAdapter.cpp b/Source/Core/InputCommon/GCAdapter.cpp
index 5cfe513935..df212e8f4e 100644
--- a/Source/Core/InputCommon/GCAdapter.cpp
+++ b/Source/Core/InputCommon/GCAdapter.cpp
@@ -66,13 +66,7 @@ static void AddGCAdapter(libusb_device* device);
 static void ResetRumbleLockNeeded();
 #endif
 
-enum class CalledFromReadThread
-{
-  No,
-  Yes,
-};
-
-static void Reset(CalledFromReadThread called_from_read_thread);
+static void Reset();
 static void Setup();
 static void ProcessInputPayload(const u8* data, std::size_t size);
 static void ReadThreadFunc();
@@ -129,24 +123,22 @@ static std::atomic<int> s_controller_write_payload_size{0};
 
 static std::thread s_read_adapter_thread;
 static Common::Flag s_read_adapter_thread_running;
-static Common::Flag s_read_adapter_thread_needs_joining;
 static std::thread s_write_adapter_thread;
 static Common::Flag s_write_adapter_thread_running;
 static Common::Event s_write_happened;
 
-static std::mutex s_read_mutex;
-#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
 static std::mutex s_init_mutex;
-#elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
+static std::mutex s_read_mutex;
+#if GCADAPTER_USE_ANDROID_IMPLEMENTATION
 static std::mutex s_write_mutex;
 #endif
 
 static std::thread s_adapter_detect_thread;
 static Common::Flag s_adapter_detect_thread_running;
 
-#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
 static Common::Event s_hotplug_event;
 
+#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
 static std::function<void(void)> s_detect_callback;
 
 #if defined(__FreeBSD__) && __FreeBSD__ >= 11
@@ -180,14 +172,14 @@ static void ReadThreadFunc()
   bool first_read = true;
   JNIEnv* const env = IDCache::GetEnvForThread();
 
-  const jfieldID payload_field = env->GetStaticFieldID(s_adapter_class, "controller_payload", "[B");
+  const jfieldID payload_field = env->GetStaticFieldID(s_adapter_class, "controllerPayload", "[B");
   jobject payload_object = env->GetStaticObjectField(s_adapter_class, payload_field);
   auto* const java_controller_payload = reinterpret_cast<jbyteArray*>(&payload_object);
 
   // Get function pointers
-  const jmethodID getfd_func = env->GetStaticMethodID(s_adapter_class, "GetFD", "()I");
-  const jmethodID input_func = env->GetStaticMethodID(s_adapter_class, "Input", "()I");
-  const jmethodID openadapter_func = env->GetStaticMethodID(s_adapter_class, "OpenAdapter", "()Z");
+  const jmethodID getfd_func = env->GetStaticMethodID(s_adapter_class, "getFd", "()I");
+  const jmethodID input_func = env->GetStaticMethodID(s_adapter_class, "input", "()I");
+  const jmethodID openadapter_func = env->GetStaticMethodID(s_adapter_class, "openAdapter", "()Z");
 
   const bool connected = env->CallStaticBooleanMethod(s_adapter_class, openadapter_func);
 
@@ -279,7 +271,7 @@ static void WriteThreadFunc()
   int size = 0;
 #elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
   JNIEnv* const env = IDCache::GetEnvForThread();
-  const jmethodID output_func = env->GetStaticMethodID(s_adapter_class, "Output", "([B)I");
+  const jmethodID output_func = env->GetStaticMethodID(s_adapter_class, "output", "([B)I");
 #endif
 
   while (s_write_adapter_thread_running.IsSet())
@@ -331,7 +323,7 @@ static int HotplugCallback(libusb_context* ctx, libusb_device* dev, libusb_hotpl
   else if (event == LIBUSB_HOTPLUG_EVENT_DEVICE_LEFT)
   {
     if (s_handle != nullptr && libusb_get_device(s_handle) == dev)
-      Reset(CalledFromReadThread::No);
+      Reset();
 
     // Reset a potential error status now that the adapter is unplugged
     if (s_status == AdapterStatus::Error)
@@ -344,6 +336,25 @@ static int HotplugCallback(libusb_context* ctx, libusb_device* dev, libusb_hotpl
   return 0;
 }
 #endif
+#elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
+extern "C" {
+
+JNIEXPORT void JNICALL
+Java_org_dolphinemu_dolphinemu_utils_GCAdapter_onAdapterConnected(JNIEnv* env, jclass)
+{
+  INFO_LOG_FMT(CONTROLLERINTERFACE, "GC adapter connected");
+  if (!s_detected)
+    s_hotplug_event.Set();
+}
+
+JNIEXPORT void JNICALL
+Java_org_dolphinemu_dolphinemu_utils_GCAdapter_onAdapterDisconnected(JNIEnv* env, jclass)
+{
+  INFO_LOG_FMT(CONTROLLERINTERFACE, "GC adapter disconnected");
+  if (s_detected)
+    Reset();
+}
+}
 #endif
 
 static void ScanThreadFunc()
@@ -393,15 +404,23 @@ static void ScanThreadFunc()
 #elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
   JNIEnv* const env = IDCache::GetEnvForThread();
 
-  const jmethodID queryadapter_func =
-      env->GetStaticMethodID(s_adapter_class, "QueryAdapter", "()Z");
+  const jmethodID enable_hotplug_callback_func =
+      env->GetStaticMethodID(s_adapter_class, "enableHotplugCallback", "()V");
+  env->CallStaticVoidMethod(s_adapter_class, enable_hotplug_callback_func);
+
+  const jmethodID is_usb_device_available_func =
+      env->GetStaticMethodID(s_adapter_class, "isUsbDeviceAvailable", "()Z");
 
   while (s_adapter_detect_thread_running.IsSet())
   {
     if (!s_detected && UseAdapter() &&
-        env->CallStaticBooleanMethod(s_adapter_class, queryadapter_func))
+        env->CallStaticBooleanMethod(s_adapter_class, is_usb_device_available_func))
+    {
+      std::lock_guard lk(s_init_mutex);
       Setup();
-    Common::SleepCurrentThread(1000);
+    }
+
+    s_hotplug_event.Wait();
   }
 #endif
 
@@ -456,7 +475,7 @@ void Init()
 #elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
   JNIEnv* const env = IDCache::GetEnvForThread();
 
-  const jclass adapter_class = env->FindClass("org/dolphinemu/dolphinemu/utils/Java_GCAdapter");
+  const jclass adapter_class = env->FindClass("org/dolphinemu/dolphinemu/utils/GCAdapter");
   s_adapter_class = reinterpret_cast<jclass>(env->NewGlobalRef(adapter_class));
 #endif
 
@@ -484,9 +503,7 @@ void StopScanThread()
 {
   if (s_adapter_detect_thread_running.TestAndClear())
   {
-#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
     s_hotplug_event.Set();
-#endif
     s_adapter_detect_thread.join();
   }
 }
@@ -523,11 +540,8 @@ static void Setup()
   s_detected = true;
 
   // Make sure the thread isn't in the middle of shutting down while starting a new one
-  if (s_read_adapter_thread_needs_joining.TestAndClear() ||
-      s_read_adapter_thread_running.TestAndClear())
-  {
+  if (s_read_adapter_thread_running.TestAndClear())
     s_read_adapter_thread.join();
-  }
 
   s_read_adapter_thread_running.Set(true);
   s_read_adapter_thread = std::thread(ReadThreadFunc);
@@ -691,8 +705,13 @@ void Shutdown()
   if (s_libusb_context && s_libusb_context->IsValid() && s_libusb_hotplug_enabled)
     libusb_hotplug_deregister_callback(*s_libusb_context, s_hotplug_handle);
 #endif
+#elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
+  JNIEnv* const env = IDCache::GetEnvForThread();
+  const jmethodID disable_hotplug_callback_func =
+      env->GetStaticMethodID(s_adapter_class, "disableHotplugCallback", "()V");
+  env->CallStaticVoidMethod(s_adapter_class, disable_hotplug_callback_func);
 #endif
-  Reset(CalledFromReadThread::No);
+  Reset();
 
 #if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
   s_libusb_context.reset();
@@ -706,12 +725,12 @@ void Shutdown()
   }
 }
 
-static void Reset(CalledFromReadThread called_from_read_thread)
+static void Reset()
 {
-#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
   std::unique_lock lock(s_init_mutex, std::defer_lock);
   if (!lock.try_lock())
     return;
+#if GCADAPTER_USE_LIBUSB_IMPLEMENTATION
   if (s_status != AdapterStatus::Detected)
     return;
 #elif GCADAPTER_USE_ANDROID_IMPLEMENTATION
@@ -719,16 +738,8 @@ static void Reset(CalledFromReadThread called_from_read_thread)
     return;
 #endif
 
-  if (called_from_read_thread == CalledFromReadThread::No)
-  {
-    if (s_read_adapter_thread_running.TestAndClear())
-      s_read_adapter_thread.join();
-  }
-  else
-  {
-    s_read_adapter_thread_needs_joining.Set();
-    s_read_adapter_thread_running.Clear();
-  }
+  if (s_read_adapter_thread_running.TestAndClear())
+    s_read_adapter_thread.join();
   // The read thread will close the write thread
 
   s_port_states.fill({});
@@ -807,9 +818,6 @@ void ProcessInputPayload(const u8* data, std::size_t size)
     // This can occur for a few frames on initialization.
     ERROR_LOG_FMT(CONTROLLERINTERFACE, "error reading payload (size: {}, type: {:02x})", size,
                   data[0]);
-#if GCADAPTER_USE_ANDROID_IMPLEMENTATION
-    Reset(CalledFromReadThread::Yes);
-#endif
   }
   else
   {