1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.hardware;
18
19import android.os.ParcelFileDescriptor;
20
21import java.io.FileDescriptor;
22import java.io.IOException;
23
24import java.nio.ByteBuffer;
25
26/**
27 * @hide
28 */
29public class SerialPort {
30
31    private static final String TAG = "SerialPort";
32
33    // used by the JNI code
34    private int mNativeContext;
35    private final String mName;
36    private ParcelFileDescriptor mFileDescriptor;
37
38    /**
39     * SerialPort should only be instantiated by SerialManager
40     * @hide
41     */
42    public SerialPort(String name) {
43        mName = name;
44    }
45
46    /**
47     * SerialPort should only be instantiated by SerialManager
48     * Speed must be one of 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600,
49     * 19200, 38400, 57600, 115200, 230400, 460800, 500000, 576000, 921600, 1000000, 1152000,
50     * 1500000, 2000000, 2500000, 3000000, 3500000, 4000000
51     *
52     * @hide
53     */
54    public void open(ParcelFileDescriptor pfd, int speed) throws IOException {
55        native_open(pfd.getFileDescriptor(), speed);
56        mFileDescriptor = pfd;
57    }
58
59    /**
60     * Closes the serial port
61     */
62    public void close() throws IOException {
63        if (mFileDescriptor != null) {
64            mFileDescriptor.close();
65            mFileDescriptor = null;
66        }
67        native_close();
68    }
69
70    /**
71     * Returns the name of the serial port
72     *
73     * @return the serial port's name
74     */
75    public String getName() {
76        return mName;
77    }
78
79    /**
80     * Reads data into the provided buffer.
81     * Note that the value returned by {@link java.nio.Buffer#position()} on this buffer is
82     * unchanged after a call to this method.
83     *
84     * @param buffer to read into
85     * @return number of bytes read
86     */
87    public int read(ByteBuffer buffer) throws IOException {
88        if (buffer.isDirect()) {
89            return native_read_direct(buffer, buffer.remaining());
90        } else if (buffer.hasArray()) {
91            return native_read_array(buffer.array(), buffer.remaining());
92        } else {
93            throw new IllegalArgumentException("buffer is not direct and has no array");
94        }
95    }
96
97    /**
98     * Writes data from provided buffer.
99     * Note that the value returned by {@link java.nio.Buffer#position()} on this buffer is
100     * unchanged after a call to this method.
101     *
102     * @param buffer to write
103     * @param length number of bytes to write
104     */
105    public void write(ByteBuffer buffer, int length) throws IOException {
106        if (buffer.isDirect()) {
107            native_write_direct(buffer, length);
108        } else if (buffer.hasArray()) {
109            native_write_array(buffer.array(), length);
110        } else {
111            throw new IllegalArgumentException("buffer is not direct and has no array");
112        }
113    }
114
115    /**
116     * Sends a stream of zero valued bits for 0.25 to 0.5 seconds
117     */
118    public void sendBreak() {
119        native_send_break();
120    }
121
122    private native void native_open(FileDescriptor pfd, int speed) throws IOException;
123    private native void native_close();
124    private native int native_read_array(byte[] buffer, int length) throws IOException;
125    private native int native_read_direct(ByteBuffer buffer, int length) throws IOException;
126    private native void native_write_array(byte[] buffer, int length) throws IOException;
127    private native void native_write_direct(ByteBuffer buffer, int length) throws IOException;
128    private native void native_send_break();
129}
130