Merge pull request #260 from Mattel/feature/allow-requesting-mtu-for-legacy-dfu

request mtu in Legacy

Author: philips77

dfu/src/main/java/no/nordicsemi/android/dfu/LegacyButtonlessDfuImpl.java

@@ -27,6 +27,7 @@
 import android.bluetooth.BluetoothGattService;
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.os.Build;
 import android.preference.PreferenceManager;
 
 import java.util.UUID;
@@ -147,6 +148,13 @@ public void performDfu(@NonNull final Intent intent) throws DfuException, Device
 
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_VERBOSE, "Jumping to the DFU Bootloader...");
 
+		// Let's request the MTU requested by the user. It may be that a lower MTU will be used.
+		if (intent.hasExtra(DfuBaseService.EXTRA_MTU) && Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+			final int requiredMtu = intent.getIntExtra(DfuBaseService.EXTRA_MTU, 517);
+			logi("Requesting MTU = " + requiredMtu);
+			requestMtu(requiredMtu);
+		}
+
 		// Enable notifications
 		enableCCCD(mControlPointCharacteristic, NOTIFICATIONS);
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, "Notifications enabled");

dfu/src/main/java/no/nordicsemi/android/dfu/LegacyDfuImpl.java

@@ -26,6 +26,7 @@
 import android.bluetooth.BluetoothGattCharacteristic;
 import android.bluetooth.BluetoothGattService;
 import android.content.Intent;
+import android.os.Build;
 import android.os.SystemClock;
 
 import java.util.Locale;
@@ -169,6 +170,13 @@ public void performDfu(@NonNull final Intent intent)
 		logw("Legacy DFU bootloader found");
 		mProgressInfo.setProgress(DfuBaseService.PROGRESS_STARTING);
 
+		// Let's request the MTU requested by the user. It may be that a lower MTU will be used.
+		if (intent.hasExtra(DfuBaseService.EXTRA_MTU) && Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+			final int requiredMtu = intent.getIntExtra(DfuBaseService.EXTRA_MTU, 517);
+			logi("Requesting MTU = " + requiredMtu);
+			requestMtu(requiredMtu);
+		}
+
 		// Add one second delay to avoid the traffic jam before the DFU mode is enabled
 		// Related:
 		//   issue:        https://github.com/NordicSemiconductor/Android-DFU-Library/issues/10