#454 Small refactoring, adding normal I2C methods for direct write (without register).

Author: DigitalSmile

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/FFMPlugin.java

@@ -7,7 +7,7 @@
 import com.pi4j.plugin.ffm.providers.gpio.DigitalInputFFMProviderImpl;
 import com.pi4j.plugin.ffm.providers.gpio.DigitalOutputFFMProviderImpl;
 import com.pi4j.plugin.ffm.providers.i2c.I2CFFMProviderImpl;
-import com.pi4j.plugin.ffm.providers.pwm.FFMPwmProviderImpl;
+import com.pi4j.plugin.ffm.providers.pwm.PwmFFMProviderImpl;
 import com.pi4j.plugin.ffm.providers.spi.SpiFFMProviderImpl;
 import com.pi4j.provider.Provider;
 
@@ -23,7 +23,7 @@ public void initialize(PluginService service) {
           new DigitalOutputFFMProviderImpl(),
           new I2CFFMProviderImpl(),
           new SpiFFMProviderImpl(),
-          new FFMPwmProviderImpl()
+          new PwmFFMProviderImpl()
         };
         service.register(providers);
     }

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/gpio/DigitalInputFFM.java

@@ -45,9 +45,9 @@ public class DigitalInputFFM extends DigitalInputBase implements DigitalInput {
     private final PullResistance pull;
     private int chipFileDescriptor;
 
-    private static final ThreadFactory factory = Thread.ofVirtual().name("pin-input-event-detection-", 0).factory();
+    private final ThreadFactory factory;
     // executor services for event watcher
-    private static final ExecutorService eventTaskProcessor = Executors.newSingleThreadExecutor(factory);
+    private final ExecutorService eventTaskProcessor;
 
     private boolean closed = false;
 
@@ -57,6 +57,8 @@ public DigitalInputFFM(String chipName, DigitalInputProvider provider, DigitalIn
         this.chipName = "/dev/" + chipName;
         this.debounce = config.debounce();
         this.pull = config.pull();
+        this.factory =  Thread.ofVirtual().name("ffm-input-event-detection-pin-", pin).factory();
+        this.eventTaskProcessor = Executors.newSingleThreadExecutor(factory);
     }
 
     @Override
@@ -237,6 +239,7 @@ public void run() {
                             if (buf[i] == 0) {
                                 continue;
                             }
+                            // convert byte array of events to java object with heap memory segment
                             System.arraycopy(buf, i, holder, 0, eventSize);
                             var memoryBuffer = MemorySegment.ofArray(holder);
                             var event = LineEvent.createEmpty().from(memoryBuffer);

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/i2c/I2CSMBus.java

@@ -1,5 +1,6 @@
 package com.pi4j.plugin.ffm.providers.i2c;
 
+import com.pi4j.exception.Pi4JException;
 import com.pi4j.io.i2c.I2CBase;
 import com.pi4j.io.i2c.I2CConfig;
 import com.pi4j.io.i2c.I2CProvider;
@@ -19,7 +20,7 @@ public class I2CSMBus extends I2CBase<I2CBusFFM> {
      *
      * @param provider a {@link I2CProvider} object.
      * @param config   a {@link I2CConfig} object.
-     * @param i2CBus   a {@link I2CBus} object.
+     * @param i2CBus   a {@link I2CBusFFM} object.
      */
     public I2CSMBus(I2CProvider provider, I2CConfig config, I2CBusFFM i2CBus) {
         super(provider, config, i2CBus);
@@ -37,12 +38,10 @@ private int writeInternal(int register, byte[] data) {
         return i2CBus.execute(this, (i2cFileDescriptor) -> {
             if (data.length == 1) {
                 return SMBUS.writeByteData(i2cFileDescriptor, (byte) register, data[0]);
+            } else if (i2CBus.hasFunctionality(I2CFunctionality.I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)) {
+                return SMBUS.writeBlockData(i2cFileDescriptor, (byte) register, data);
             } else {
-                return 0;
-//                var buffer = new byte[data.length + 1];
-//                buffer[0] = (byte) register;
-//                System.arraycopy(data, 0, buffer, 1, data.length);
-//                return FILE.write(i2cFileDescriptor, buffer);
+                throw new Pi4JException("No support any of I2C device write mode.");
             }
         });
     }
@@ -57,12 +56,12 @@ private int writeInternal(int register, byte[] data) {
     private byte[] readInternal(int register, int size) {
         i2CBus.selectDevice(config.device());
         return i2CBus.execute(this, (i2cFileDescriptor) -> {
-            //FILE.write(i2cFileDescriptor, new byte[]{(byte) register});
-            //return FILE.read(i2cFileDescriptor, new byte[size], size);
             if (size == 1) {
                 return new byte[] {SMBUS.readByteData(i2cFileDescriptor, (byte) register)};
+            } else if (i2CBus.hasFunctionality(I2CFunctionality.I2C_FUNC_SMBUS_READ_BLOCK_DATA)) {
+                return SMBUS.readBlockData(i2cFileDescriptor, (byte) register, new byte[size]);
             } else {
-                return new byte[0];
+                throw new Pi4JException("No support any of I2C device read mode.");
             }
         });
     }
@@ -71,13 +70,15 @@ private byte[] readInternal(int register, int size) {
     @Override
     public int read() {
         i2CBus.selectDevice(config.device());
+        // this is needed, because we are receiving raw bytes, which we have to convert to proper int
         return Byte.toUnsignedInt(i2CBus.execute(this, SMBUS::readByte));
     }
 
     @Override
-    public int read(byte[] buffer, int offset, int length) {
-        //TODO: how to implement? That is not a part os standard
-        return 0;
+    public int read(byte[] data, int offset, int length) {
+        var buffer = new byte[data.length - 1];
+        System.arraycopy(data, 1, buffer, 0, length);
+        return readRegister(data[0], buffer, offset, length);
     }
 
     @Override
@@ -88,19 +89,30 @@ public int write(byte b) {
 
     @Override
     public int write(byte[] data, int offset, int length) {
-        //TODO: how to implement? That is not a part os standard
-        return 0;
+        var buffer = new byte[data.length - 1];
+        System.arraycopy(data, 1, buffer, 0, length);
+        return writeRegister(data[0], buffer, offset, length);
     }
 
     @Override
     public int readRegister(int register) {
+        i2CBus.selectDevice(config.device());
+        // this is needed, because we are receiving raw bytes, which we have to convert to proper int
         return Byte.toUnsignedInt(readInternal(register, 1)[0]);
     }
 
     @Override
-    public int readRegister(byte[] register, byte[] buffer, int offset, int length) {
-        //TODO: how to implement? That is not a part os standard
-        return 0;
+    public int readRegister(byte[] register, byte[] data, int offset, int length) {
+        Objects.checkFromIndexSize(offset, length, data.length);
+        // Prepare the data for multibyte register
+        // Sequence:
+        //      - set address to first byte, all other bytes send with data.
+        //      - read the byte without address (internal chip cursor will point to the correct address)
+        var byteRegister = register[0];
+        var readData = new byte[data.length + register.length - 1];
+        System.arraycopy(Arrays.copyOfRange(register, 1, register.length), 0, readData, 0, register.length - 1);
+        System.arraycopy(data, 0, readData, register.length - 1, data.length);
+        return readRegister(byteRegister, readData);
     }
 
     @Override

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/pwm/FFMPWM.java renamed to plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/pwm/PwmFFM.java

@@ -10,11 +10,11 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-public class FFMPWM extends PwmBase implements Pwm {
+public class PwmFFM extends PwmBase implements Pwm {
     protected Logger logger = LoggerFactory.getLogger(this.getClass());
 
 
-    public FFMPWM(PwmProvider provider, PwmConfig config, int range){
+    public PwmFFM(PwmProvider provider, PwmConfig config, int range){
         super(provider, config);
     }
 

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/pwm/FFMPwmProviderImpl.java renamed to plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/pwm/PwmFFMProviderImpl.java

@@ -5,9 +5,9 @@
 import com.pi4j.io.pwm.PwmProvider;
 import com.pi4j.io.pwm.PwmProviderBase;
 
-public class FFMPwmProviderImpl extends PwmProviderBase implements PwmProvider {
+public class PwmFFMProviderImpl extends PwmProviderBase implements PwmProvider {
 
-    public FFMPwmProviderImpl() {
+    public PwmFFMProviderImpl() {
         this.id = "FFMPwmProviderImpl";
         this.name = "FFMPwmProviderImpl";
     }

plugins/pi4j-plugin-ffm/src/main/java/com/pi4j/plugin/ffm/providers/spi/SpiFFM.java

@@ -24,17 +24,17 @@ public class SpiFFM extends SpiBase implements Spi {
 
 
     private int spiFileDescriptor;
-    private String path;
+    private final String path;
 
     public SpiFFM(SpiProvider provider, SpiConfig config) {
         super(provider, config);
+        this.path = SPI_BUS + config.bus().getBus() + "." + config.address();
     }
 
     @Override
     public Spi initialize(Context context) throws InitializeException {
         super.initialize(context);
 
-        path = SPI_BUS + config.bus().getBus() + "." + config.address();
         logger.info("{} - setting up SPIBus...", path);
         logger.debug("{} - opening device file.", path);
         this.spiFileDescriptor = FILE.open(path, FileFlag.O_RDWR);