new getControlLines() and getSupportedControLines() methods

getControlLines() requires less USB calls than calling getRTS() + ... + getRI() individually.
getSupportedControlLines() tells you, which control lines are supported by a driver. Previously you had to check the driver implementation.

usbSerialExamples/src/main/java/com/hoho/android/usbserial/examples/TerminalFragment.java

@@ -37,6 +37,7 @@ import com.hoho.android.usbserial.util.SerialInputOutputManager;
 
 import java.io.IOException;
 import java.util.Arrays;
+import java.util.EnumSet;
 import java.util.concurrent.Executors;
 
 public class TerminalFragment extends Fragment implements SerialInputOutputManager.Listener {
@@ -312,29 +313,42 @@ public class TerminalFragment extends Fragment implements SerialInputOutputManag
                 if (btn.equals(rtsBtn)) { ctrl = "RTS"; usbSerialPort.setRTS(btn.isChecked()); }
                 if (btn.equals(dtrBtn)) { ctrl = "DTR"; usbSerialPort.setDTR(btn.isChecked()); }
             } catch (IOException e) {
-                status("set" + ctrl + " failed: " + e.getMessage());
+                status("set" + ctrl + "() failed: " + e.getMessage());
             }
         }
 
         private boolean refresh() {
-            String ctrl = "";
             try {
-                ctrl = "RTS"; rtsBtn.setChecked(usbSerialPort.getRTS());
+                EnumSet<UsbSerialPort.ControlLine> controlLines = usbSerialPort.getControlLines();
-                ctrl = "CTS"; ctsBtn.setChecked(usbSerialPort.getCTS());
+                rtsBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.RTS));
-                ctrl = "DTR"; dtrBtn.setChecked(usbSerialPort.getDTR());
+                ctsBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.CTS));
-                ctrl = "DSR"; dsrBtn.setChecked(usbSerialPort.getDSR());
+                dtrBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.DTR));
-                ctrl = "CD";  cdBtn.setChecked(usbSerialPort.getCD());
+                dsrBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.DSR));
-                ctrl = "RI";  riBtn.setChecked(usbSerialPort.getRI());
+                cdBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.CD));
+                riBtn.setChecked(controlLines.contains(UsbSerialPort.ControlLine.RI));
             } catch (IOException e) {
-                status("get" + ctrl + " failed: " + e.getMessage() + " -> stopped control line refresh");
+                status("getControlLines() failed: " + e.getMessage() + " -> stopped control line refresh");
                 return false;
             }
             return true;
         }
 
         void start() {
-            if (connected && refresh())
+            if (connected) {
-                mainLooper.postDelayed(runnable, refreshInterval);
+                try {
+                    EnumSet<UsbSerialPort.ControlLine> controlLines = usbSerialPort.getSupportedControlLines();
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.RTS)) rtsBtn.setVisibility(View.INVISIBLE);
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.CTS)) ctsBtn.setVisibility(View.INVISIBLE);
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.DTR)) dtrBtn.setVisibility(View.INVISIBLE);
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.DSR)) dsrBtn.setVisibility(View.INVISIBLE);
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.CD))   cdBtn.setVisibility(View.INVISIBLE);
+                    if (!controlLines.contains(UsbSerialPort.ControlLine.RI))   riBtn.setVisibility(View.INVISIBLE);
+                } catch (IOException e) {
+                    Toast.makeText(getActivity(), "getSupportedControlLines() failed: " + e.getMessage(), Toast.LENGTH_SHORT).show();
+                }
+                if (refresh())
+                    mainLooper.postDelayed(runnable, refreshInterval);
+            }
         }
 
         void stop() {

usbSerialForAndroid/build.gradle

@@ -11,7 +11,7 @@ android {
         
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         testInstrumentationRunnerArguments = [                    // Raspi   Windows   LinuxVM   ...
-                'rfc2217_server_host': '192.168.0.100',
+                'rfc2217_server_host': '192.168.0.110',
                 'rfc2217_server_nonstandard_baudrates': 'true',   // true    false     false
         ]
     }

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

@@ -1564,12 +1564,20 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
             inputLinesSupported = true;
             inputLinesConnected = true;
         }
+        EnumSet<UsbSerialPort.ControlLine> supportedControlLines = EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR);
+        if(inputLinesSupported) {
+            supportedControlLines.add(UsbSerialPort.ControlLine.CTS);
+            supportedControlLines.add(UsbSerialPort.ControlLine.DSR);
+            supportedControlLines.add(UsbSerialPort.ControlLine.CD);
+            supportedControlLines.add(UsbSerialPort.ControlLine.RI);
+        }
 
         usbOpen(EnumSet.of(UsbOpenFlags.NO_CONTROL_LINE_INIT));
         usbParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
         telnetParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
         Thread.sleep(sleep);
 
+        assertEquals(supportedControlLines, usbSerialPort.getSupportedControlLines());
         if(usbSerialDriver instanceof ProlificSerialDriver) {
             // the initial status is sometimes not available or wrong.
             // this is more likely if other tests have been executed before.
@@ -1579,6 +1587,10 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
             assertTrue(usbSerialPort.getRI());
         }
         data = "none".getBytes();
+        assertEquals(inputLinesConnected
+                        ? EnumSet.of(UsbSerialPort.ControlLine.RI)
+                        : EnumSet.noneOf(UsbSerialPort.ControlLine.class),
+                usbSerialPort.getControlLines());
         assertFalse(usbSerialPort.getRTS());
         assertFalse(usbSerialPort.getCTS());
         assertFalse(usbSerialPort.getDTR());
@@ -1598,6 +1610,10 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         data = "rts ".getBytes();
         usbSerialPort.setRTS(true);
         Thread.sleep(sleep);
+        assertEquals(inputLinesConnected
+                        ? EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.CTS)
+                        : EnumSet.of(UsbSerialPort.ControlLine.RTS),
+                usbSerialPort.getControlLines());
         assertTrue(usbSerialPort.getRTS());
         assertEquals(usbSerialPort.getCTS(), inputLinesConnected);
         assertFalse(usbSerialPort.getDTR());
@@ -1612,6 +1628,10 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         data = "both".getBytes();
         usbSerialPort.setDTR(true);
         Thread.sleep(sleep);
+        assertEquals(inputLinesConnected
+                        ? EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR, UsbSerialPort.ControlLine.CD)
+                        : EnumSet.of(UsbSerialPort.ControlLine.RTS, UsbSerialPort.ControlLine.DTR),
+                usbSerialPort.getControlLines());
         assertTrue(usbSerialPort.getRTS());
         assertFalse(usbSerialPort.getCTS());
         assertTrue(usbSerialPort.getDTR());
@@ -1626,6 +1646,10 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         data = "dtr ".getBytes();
         usbSerialPort.setRTS(false);
         Thread.sleep(sleep);
+        assertEquals(inputLinesConnected
+                        ? EnumSet.of(UsbSerialPort.ControlLine.DTR, UsbSerialPort.ControlLine.DSR)
+                        : EnumSet.of(UsbSerialPort.ControlLine.DTR),
+                usbSerialPort.getControlLines());
         assertFalse(usbSerialPort.getRTS());
         assertFalse(usbSerialPort.getCTS());
         assertTrue(usbSerialPort.getDTR());
@@ -1646,6 +1670,10 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         usbOpen(EnumSet.of(UsbOpenFlags.NO_CONTROL_LINE_INIT, UsbOpenFlags.NO_IOMANAGER_THREAD));
         usbParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
 
+        EnumSet<UsbSerialPort.ControlLine> retainedControlLines = EnumSet.noneOf(UsbSerialPort.ControlLine.class);
+        if(outputRetained) retainedControlLines.add(UsbSerialPort.ControlLine.DTR);
+        if(inputRetained)  retainedControlLines.add(UsbSerialPort.ControlLine.DSR);
+        assertEquals(retainedControlLines, usbSerialPort.getControlLines());
         assertFalse(usbSerialPort.getRTS());
         assertFalse(usbSerialPort.getCTS());
         assertEquals(usbSerialPort.getDTR(), outputRetained);

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

@@ -30,6 +30,7 @@ import android.util.Log;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -300,6 +301,18 @@ public class CdcAcmSerialDriver implements UsbSerialDriver {
             sendAcmControlMessage(SET_CONTROL_LINE_STATE, value, null);
         }
 
+        @Override
+        public EnumSet<ControlLine> getControlLines() throws IOException {
+            EnumSet<ControlLine> set = EnumSet.noneOf(ControlLine.class);
+            if(mRts) set.add(ControlLine.RTS);
+            if(mDtr) set.add(ControlLine.DTR);
+            return set;
+        }
+
+        @Override
+        public EnumSet<ControlLine> getSupportedControlLines() throws IOException {
+            return EnumSet.of(ControlLine.RTS, ControlLine.DTR);
+        }
     }
 
     public static Map<Integer, int[]> getSupportedDevices() {

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

@@ -28,6 +28,7 @@ import android.hardware.usb.UsbInterface;
 
 import java.io.IOException;
 import java.util.Collections;
+import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -173,7 +174,7 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 			}
 		}
 
-		private byte getControlLines() throws IOException {
+		private byte getStatus() throws IOException {
 			byte[] buffer = new byte[2];
 			int ret = controlIn(0x95, 0x0706, 0, buffer);
 			if (ret < 0)
@@ -304,17 +305,17 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 
 		@Override
 		public boolean getCD() throws IOException {
-			return (getControlLines() & GCL_CD) == 0;
+			return (getStatus() & GCL_CD) == 0;
 		}
 
 		@Override
 		public boolean getCTS() throws IOException {
-			return (getControlLines() & GCL_CTS) == 0;
+			return (getStatus() & GCL_CTS) == 0;
 		}
 
 		@Override
 		public boolean getDSR() throws IOException {
-			return (getControlLines() & GCL_DSR) == 0;
+			return (getStatus() & GCL_DSR) == 0;
 		}
 
 		@Override
@@ -330,7 +331,7 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 
 		@Override
 		public boolean getRI() throws IOException {
-			return (getControlLines() & GCL_RI) == 0;
+			return (getStatus() & GCL_RI) == 0;
 		}
 
 		@Override
@@ -344,6 +345,23 @@ public class Ch34xSerialDriver implements UsbSerialDriver {
 			setControlLines();
 		}
 
+		@Override
+		public EnumSet<ControlLine> getControlLines() throws IOException {
+			int status = getStatus();
+			EnumSet<ControlLine> set = EnumSet.noneOf(ControlLine.class);
+			if(rts) set.add(ControlLine.RTS);
+			if((status & GCL_CTS) == 0) set.add(ControlLine.CTS);
+			if(dtr) set.add(ControlLine.DTR);
+			if((status & GCL_DSR) == 0) set.add(ControlLine.DSR);
+			if((status & GCL_CD) == 0) set.add(ControlLine.CD);
+			if((status & GCL_RI) == 0) set.add(ControlLine.RI);
+			return set;
+		}
+
+		@Override
+		public EnumSet<ControlLine> getSupportedControlLines() throws IOException {
+			return EnumSet.allOf(ControlLine.class);
+		}
 	}
 
 	public static Map<Integer, int[]> getSupportedDevices() {

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

@@ -29,6 +29,7 @@ import android.util.Log;
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.util.EnumSet;
 
 /**
  * A base class shared by several driver implementations.
@@ -249,6 +250,12 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
     @Override
     public abstract void setRTS(boolean value) throws IOException;
 
+    @Override
+    public abstract EnumSet<ControlLine> getControlLines() throws IOException;
+
+    @Override
+    public abstract EnumSet<ControlLine> getSupportedControlLines() throws IOException;
+
     @Override
     public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
         return false;

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

@@ -29,6 +29,7 @@ import android.hardware.usb.UsbInterface;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -299,6 +300,19 @@ public class Cp21xxSerialDriver implements UsbSerialDriver {
             setConfigSingle(SILABSER_SET_DTR_RTS_REQUEST_CODE, rts ? RTS_ENABLE : RTS_DISABLE);
         }
 
+        @Override
+        public EnumSet<ControlLine> getControlLines() throws IOException {
+            EnumSet<ControlLine> set = EnumSet.noneOf(ControlLine.class);
+            if(rts) set.add(ControlLine.RTS);
+            if(dtr) set.add(ControlLine.DTR);
+            return set;
+        }
+
+        @Override
+        public EnumSet<ControlLine> getSupportedControlLines() throws IOException {
+            return EnumSet.of(ControlLine.RTS, ControlLine.DTR);
+        }
+
         @Override
         public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             int value = (purgeReadBuffers ? FLUSH_READ_CODE : 0)

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

@@ -28,6 +28,7 @@ import android.util.Log;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -527,6 +528,24 @@ public class FtdiSerialDriver implements UsbSerialDriver {
             mRtsState = value;
         }
 
+        @Override
+        public EnumSet<ControlLine> getControlLines() throws IOException {
+            int status = getModemStatus();
+            EnumSet<ControlLine> set = EnumSet.noneOf(ControlLine.class);
+            if(mRtsState) set.add(ControlLine.RTS);
+            if((status & SIO_MODEM_STATUS_CTS) != 0) set.add(ControlLine.CTS);
+            if(mDtrState) set.add(ControlLine.DTR);
+            if((status & SIO_MODEM_STATUS_DSR) != 0) set.add(ControlLine.DSR);
+            if((status & SIO_MODEM_STATUS_RLSD) != 0) set.add(ControlLine.CD);
+            if((status & SIO_MODEM_STATUS_RI) != 0) set.add(ControlLine.RI);
+            return set;
+        }
+
+        @Override
+        public EnumSet<ControlLine> getSupportedControlLines() throws IOException {
+            return EnumSet.allOf(ControlLine.class);
+        }
+
         @Override
         public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             if (purgeWriteBuffers) {

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

@@ -37,6 +37,7 @@ import android.util.Log;
 import java.io.IOException;
 import java.lang.reflect.Method;
 import java.util.Collections;
+import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -426,7 +427,7 @@ public class ProlificSerialDriver implements UsbSerialDriver {
 
         @Override
         public boolean getDTR() throws IOException {
-            return ((mControlLinesValue & CONTROL_DTR) == CONTROL_DTR);
+            return (mControlLinesValue & CONTROL_DTR) != 0;
         }
 
         @Override
@@ -447,7 +448,7 @@ public class ProlificSerialDriver implements UsbSerialDriver {
 
         @Override
         public boolean getRTS() throws IOException {
-            return ((mControlLinesValue & CONTROL_RTS) == CONTROL_RTS);
+            return (mControlLinesValue & CONTROL_RTS) != 0;
         }
 
         @Override
@@ -461,6 +462,25 @@ public class ProlificSerialDriver implements UsbSerialDriver {
             setControlLines(newControlLinesValue);
         }
 
+
+        @Override
+        public EnumSet<ControlLine> getControlLines() throws IOException {
+            int status = getStatus();
+            EnumSet<ControlLine> set = EnumSet.noneOf(ControlLine.class);
+            if((mControlLinesValue & CONTROL_RTS) != 0) set.add(ControlLine.RTS);
+            if((status & STATUS_FLAG_CTS) != 0) set.add(ControlLine.CTS);
+            if((mControlLinesValue & CONTROL_DTR) != 0) set.add(ControlLine.DTR);
+            if((status & STATUS_FLAG_DSR) != 0) set.add(ControlLine.DSR);
+            if((status & STATUS_FLAG_CD) != 0) set.add(ControlLine.CD);
+            if((status & STATUS_FLAG_RI) != 0) set.add(ControlLine.RI);
+            return set;
+        }
+
+        @Override
+        public EnumSet<ControlLine> getSupportedControlLines() throws IOException {
+            return EnumSet.allOf(ControlLine.class);
+        }
+
         @Override
         public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException {
             if (purgeWriteBuffers) {

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

@@ -27,6 +27,7 @@ import android.hardware.usb.UsbManager;
 
 import java.io.Closeable;
 import java.io.IOException;
+import java.util.EnumSet;
 
 /**
  * Interface for a single serial port.
@@ -86,6 +87,12 @@ public interface UsbSerialPort extends Closeable {
     /** 2 stop bits. */
     public static final int STOPBITS_2 = 2;
 
+    /** values for get[Supported]ControlLines() */
+    public enum ControlLine { RTS, CTS,  DTR, DSR,  CD, RI };
+
+    /**
+     * Returns the driver used by this port.
+     */
     public UsbSerialDriver getDriver();
 
     /**
@@ -100,6 +107,9 @@ public interface UsbSerialPort extends Closeable {
     
     /**
      * The serial number of the underlying UsbDeviceConnection, or {@code null}.
+     *
+     * @return value from {@link UsbDeviceConnection#getSerial()}
+     * @throws SecurityException starting with target SDK 29 (Android 10) if permission for USB device is not granted
      */
     public String getSerial();
 
@@ -189,8 +199,7 @@ public interface UsbSerialPort extends Closeable {
     public boolean getDTR() throws IOException;
 
     /**
-     * Sets the DTR (Data Terminal Ready) bit on the underlying UART, if
+     * Sets the DTR (Data Terminal Ready) bit on the underlying UART, if supported.
-     * supported.
      *
      * @param value the value to set
      * @throws IOException if an error occurred during writing
@@ -214,14 +223,30 @@ public interface UsbSerialPort extends Closeable {
     public boolean getRTS() throws IOException;
 
     /**
-     * Sets the RTS (Request To Send) bit on the underlying UART, if
+     * Sets the RTS (Request To Send) bit on the underlying UART, if supported.
-     * supported.
      *
      * @param value the value to set
      * @throws IOException if an error occurred during writing
      */
     public void setRTS(boolean value) throws IOException;
 
+    /**
+     * Gets all control line values from the underlying UART, if supported.
+     * Requires less USB calls than calling getRTS() + ... + getRI() individually.
+     *
+     * @return EnumSet.contains(...) is {@code true} if set, else {@code false}
+     * @throws IOException
+     */
+    public EnumSet<ControlLine> getControlLines() throws IOException;
+
+    /**
+     * Gets all control line supported flags.
+     *
+     * @return EnumSet.contains(...) is {@code true} if supported, else {@code false}
+     * @throws IOException
+     */
+    public EnumSet<ControlLine> getSupportedControlLines() throws IOException;
+
     /**
      * purge non-transmitted output data and / or non-read input data
      * @param purgeWriteBuffers {@code true} to discard non-transmitted output data