reuse UsbRequest

less LogCat output

build.gradle

@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.1'
+        classpath 'com.android.tools.build:gradle:3.5.3'
     }
 }
 

usbSerialForAndroid/publishToMavenLocal.gradle

@@ -5,7 +5,7 @@ publishing {
         maven(MavenPublication) {
             groupId 'com.github.mik3y'
             artifactId 'usb-serial-for-android'
-            version '2.1.0a'
+            version '2.2.0a'
             afterEvaluate {
                 artifact androidSourcesJar
                 artifact bundleReleaseAar

usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/DeviceTest.java

@@ -1097,7 +1097,7 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
 
     private int readSpeedInt(int writeSeconds, int readTimeout) throws Exception {
         int baudrate = 115200;
-        if(usbSerialDriver instanceof Ch34xSerialDriver && readTimeout != 0)
+        if(usbSerialDriver instanceof Ch34xSerialDriver)
             baudrate = 38400;
         int writeAhead = 5*baudrate/10; // write ahead for another 5 second read
         if(usbSerialDriver instanceof CdcAcmSerialDriver)
@@ -1355,8 +1355,6 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
 
         int longTimeout = 1000;
         int shortTimeout = 10;
-        if(usbSerialDriver instanceof Ch34xSerialDriver)
-            shortTimeout = 20; // too short timeout causes mysterious effects like lost telnet data
         time = System.currentTimeMillis();
         len = usbSerialPort.read(buf, shortTimeout);
         assertEquals(0, len);

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CdcAcmSerialDriver.java

@@ -94,14 +94,7 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public void open(UsbDeviceConnection connection) throws IOException {
+        public void openInt(UsbDeviceConnection connection) throws IOException {
-            if (mConnection != null) {
-                throw new IOException("Already open");
-            }
-
-            mConnection = connection;
-            boolean opened = false;
-            try {
             if (1 == mDevice.getInterfaceCount()) {
                 Log.d(TAG,"device might be castrated ACM device, trying single interface logic");
                 openSingleInterface();
@@ -109,12 +102,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
                 Log.d(TAG,"trying default interface logic");
                 openInterface();
             }
-                opened = true;
-            } finally {
-                if (!opened) {
-                    close();
-                }
-            }
         }
 
         private void openSingleInterface() throws IOException {
@@ -224,9 +211,6 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
                 if (ep.getDirection() == UsbConstants.USB_DIR_OUT && ep.getType() == UsbConstants.USB_ENDPOINT_XFER_BULK)
                     mWriteEndpoint = ep;
             }
-            if (mReadEndpoint == null || mWriteEndpoint == null) {
-                throw new IOException("Could not get read&write endpoints");
-            }
         }
 
         private int sendAcmControlMessage(int request, int value, byte[] buf) throws IOException {

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/Ch34xSerialDriver.java

@@ -90,14 +90,7 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 		}
 
 		@Override
-		public void open(UsbDeviceConnection connection) throws IOException {
+		public void openInt(UsbDeviceConnection connection) throws IOException {
-			if (mConnection != null) {
-				throw new IOException("Already open");
-			}
-
-			mConnection = connection;
-			boolean opened = false;
-			try {
 			for (int i = 0; i < mDevice.getInterfaceCount(); i++) {
 				UsbInterface usbIface = mDevice.getInterface(i);
 				if (!mConnection.claimInterface(usbIface, true)) {
@@ -119,13 +112,6 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 
 			initialize();
 			setBaudRate(DEFAULT_BAUD_RATE);
-
-				opened = true;
-			} finally {
-				if (!opened) {
-					close();
-				}
-			}
 		}
 
 		@Override

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java

@@ -107,28 +107,44 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
     }
 
     @Override
-    public abstract void open(UsbDeviceConnection connection) throws IOException;
+    public void open(UsbDeviceConnection connection) throws IOException {
+        if (mConnection != null) {
+            throw new IOException("Already open");
+        }
+        mConnection = connection;
+        try {
+            openInt(connection);
+            if (mReadEndpoint == null || mWriteEndpoint == null) {
+                throw new IOException("Could not get read & write endpoints");
+            }
+            mUsbRequest = new UsbRequest();
+            mUsbRequest.initialize(mConnection, mReadEndpoint);
+        } catch(Exception e) {
+            close();
+            throw e;
+        }
+    }
+
+    protected abstract void openInt(UsbDeviceConnection connection) throws IOException;
 
     @Override
     public void close() throws IOException {
         if (mConnection == null) {
             throw new IOException("Already closed");
         }
-        synchronized (this) {
+        try {
-            if (mUsbRequest != null)
             mUsbRequest.cancel();
-        }
+        } catch(Exception ignored) {}
+        mUsbRequest = null;
         try {
             closeInt();
         } catch(Exception ignored) {}
         try {
             mConnection.close();
-        } finally {
+        } catch(Exception ignored) {}
         mConnection = null;
     }
 
-    }
-
     protected abstract void closeInt();
 
     @Override
@@ -150,26 +166,15 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
             nread = mConnection.bulkTransfer(mReadEndpoint, dest, readMax, timeout);
 
         } else {
-            final UsbRequest request = new UsbRequest();
-            try {
-                request.initialize(mConnection, mReadEndpoint);
             final ByteBuffer buf = ByteBuffer.wrap(dest);
-                if (!request.queue(buf, dest.length)) {
+            if (!mUsbRequest.queue(buf, dest.length)) {
-                    throw new IOException("Error queueing request");
+                throw new IOException("Queueing USB request failed");
             }
-                mUsbRequest = request;
             final UsbRequest response = mConnection.requestWait();
-                synchronized (this) {
-                    mUsbRequest = null;
-                }
             if (response == null) {
-                    throw new IOException("Null response");
+                throw new IOException("Waiting for USB request failed");
             }
             nread = buf.position();
-            } finally {
-                mUsbRequest = null;
-                request.close();
-            }
         }
         if (nread > 0) {
             return readFilter(dest, nread);

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/Cp21xxSerialDriver.java

@@ -138,15 +138,8 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public void open(UsbDeviceConnection connection) throws IOException {
+        public void openInt(UsbDeviceConnection connection) throws IOException {
-            if (mConnection != null) {
-                throw new IOException("Already open");
-            }
-
-            mConnection = connection;
-            boolean opened = false;
             mIsRestrictedPort = mDevice.getInterfaceCount() == 2 && mPortNumber == 1;
-            try {
             if(mPortNumber >= mDevice.getInterfaceCount()) {
                 throw new IOException("Unknown port number");
             }
@@ -169,12 +162,6 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
             setConfigSingle(SILABSER_SET_MHS_REQUEST_CODE, MCR_ALL | CONTROL_WRITE_DTR | CONTROL_WRITE_RTS);
             setConfigSingle(SILABSER_SET_BAUDDIV_REQUEST_CODE, BAUD_RATE_GEN_FREQ / DEFAULT_BAUD_RATE);
 //            setParameters(DEFAULT_BAUD_RATE, DEFAULT_DATA_BITS, DEFAULT_STOP_BITS, DEFAULT_PARITY);
-                opened = true;
-            } finally {
-                if (!opened) {
-                    close();
-                }
-            }
         }
 
         @Override

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/FtdiSerialDriver.java

@@ -295,14 +295,7 @@ public class FtdiSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public void open(UsbDeviceConnection connection) throws IOException {
+        public void openInt(UsbDeviceConnection connection) throws IOException {
-            if (mConnection != null) {
-                throw new IOException("Already open");
-            }
-            mConnection = connection;
-
-            boolean opened = false;
-            try {
             if (connection.claimInterface(mDevice.getInterface(mPortNumber), true)) {
                 Log.d(TAG, "claimInterface " + mPortNumber + " SUCCESS");
             } else {
@@ -315,12 +308,6 @@ public class FtdiSerialDriver implements UsbSerialDriver {
             mReadEndpoint = mDevice.getInterface(mPortNumber).getEndpoint(0);
             mWriteEndpoint = mDevice.getInterface(mPortNumber).getEndpoint(1);
             reset();
-                opened = true;
-            } finally {
-                if (!opened) {
-                    close();
-                }
-            }
         }
 
         @Override

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/ProlificSerialDriver.java

@@ -263,20 +263,13 @@ public class ProlificSerialDriver implements UsbSerialDriver {
         }
 
         @Override
-        public void open(UsbDeviceConnection connection) throws IOException {
+        public void openInt(UsbDeviceConnection connection) throws IOException {
-            if (mConnection != null) {
-                throw new IOException("Already open");
-            }
-
             UsbInterface usbInterface = mDevice.getInterface(0);
 
             if (!connection.claimInterface(usbInterface, true)) {
                 throw new IOException("Error claiming Prolific interface 0");
             }
 
-            mConnection = connection;
-            boolean opened = false;
-            try {
             for (int i = 0; i < usbInterface.getEndpointCount(); ++i) {
                 UsbEndpoint currentEndpoint = usbInterface.getEndpoint(i);
 
@@ -324,17 +317,9 @@ public class ProlificSerialDriver implements UsbSerialDriver {
                             + "to detect PL2303 subtype", e);
                 }
             }
-
             setControlLines(mControlLinesValue);
             resetDevice();
-
             doBlackMagic();
-                opened = true;
-            } finally {
-                if (!opened) {
-                    close();
-                }
-            }
         }
 
         @Override