TwiMasterImpl.java

/*
 * Copyright 2011 Ytai Ben-Tsvi. All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of
 *       conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list
 *       of conditions and the following disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ARSHAN POURSOHI OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * The views and conclusions contained in the software and documentation are those of the
 * authors and should not be interpreted as representing official policies, either expressed
 * or implied.
 */
package ioio.lib.impl;

import java.io.IOException;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;

import ioio.lib.api.TwiMaster;
import ioio.lib.api.exception.ConnectionLostException;
import ioio.lib.impl.FlowControlledPacketSender.Packet;
import ioio.lib.impl.FlowControlledPacketSender.Sender;
import ioio.lib.impl.IncomingState.DataModuleListener;
import ioio.lib.impl.ResourceManager.Resource;
import ioio.lib.spi.Log;

class TwiMasterImpl extends AbstractResource implements TwiMaster,
        DataModuleListener, Sender {
    class TwiResult extends ResourceLifeCycle implements Result {
        private boolean ready_ = false;
        private boolean success_;
        private final byte[] data_;

        public TwiResult(byte[] data) {
            data_ = data;
        }

        public synchronized void ready(boolean success) {
            ready_ = true;
            success_ = success;
            notifyAll();
        }

        public byte[] getData() {
            return data_;
        }

        @Override
        public synchronized boolean waitReady() throws ConnectionLostException,
                InterruptedException {
            checkState();
            while (!ready_) {
                safeWait();
            }
            return success_;
        }
    }

    class OutgoingPacket implements Packet {
        int writeSize_;
        byte[] writeData_;
        boolean tenBitAddr_;
        int addr_;
        int readSize_;

        @Override
        public int getSize() {
            return writeSize_ + 4;
        }

    }

    private final Queue<TwiResult> pendingRequests_ = new ConcurrentLinkedQueue<TwiMasterImpl.TwiResult>();
    private final FlowControlledPacketSender outgoing_ = new FlowControlledPacketSender(
            this);
    private final Resource twi_;
    private final Resource[] pins_;

    TwiMasterImpl(IOIOImpl ioio, Resource twi, Resource[] pins) throws ConnectionLostException {
        super(ioio);
        twi_ = twi;
        pins_ = pins;
    }

    @Override
    synchronized public void disconnected() {
        outgoing_.kill();
        for (TwiResult result : pendingRequests_) {
            result.disconnected();
        }
        super.disconnected();
    }

    @Override
    public boolean writeRead(int address, boolean tenBitAddr, byte[] writeData,
                             int writeSize, byte[] readData, int readSize)
            throws ConnectionLostException, InterruptedException {
        Result result = writeReadAsync(address, tenBitAddr, writeData,
                writeSize, readData, readSize);
        return result.waitReady();
    }

    @Override
    public Result writeReadAsync(int address, boolean tenBitAddr,
                                 byte[] writeData, int writeSize, byte[] readData, int readSize)
            throws ConnectionLostException {
        checkState();
        TwiResult result = new TwiResult(readData);

        OutgoingPacket p = new OutgoingPacket();
        p.writeSize_ = writeSize;
        p.writeData_ = writeData;
        p.tenBitAddr_ = tenBitAddr;
        p.readSize_ = readSize;
        p.addr_ = address;

        synchronized (this) {
            pendingRequests_.add(result);
            try {
                outgoing_.write(p);
            } catch (IOException e) {
                Log.e("SpiMasterImpl", "Exception caught", e);
            }
        }
        return result;
    }

    @Override
    public void dataReceived(byte[] data, int size) {
        TwiResult result = pendingRequests_.remove();
        synchronized (result) {
            final boolean success = size != 0xFF;
            if (success && size > 0) {
                System.arraycopy(data, 0, result.getData(), 0, size);
            }
            result.ready(success);
        }
    }

    @Override
    public void reportAdditionalBuffer(int bytesRemaining) {
        outgoing_.readyToSend(bytesRemaining);
    }

    @Override
    synchronized public void close() {
        checkClose();
        outgoing_.close();
        for (TwiResult result : pendingRequests_) {
            result.close();
        }
        try {
            ioio_.protocol_.i2cClose(twi_.id);
            ioio_.resourceManager_.free(twi_, pins_);
        } catch (IOException e) {
        }
        super.close();
    }

    @Override
    public void send(Packet packet) {
        OutgoingPacket p = (OutgoingPacket) packet;
        try {
            ioio_.protocol_.i2cWriteRead(twi_.id, p.tenBitAddr_, p.addr_,
                    p.writeSize_, p.readSize_, p.writeData_);
        } catch (IOException e) {
            Log.e("TwiImpl", "Caught exception", e);
        }
    }
}