當 USB 設備連接到 Android 設備時會發生什么？
作者：Reathin
當USB設備掛載連接到時，操作系統會檢測設備的VID和PID，根據這些信息加載相應的驅動程序，確保設備能夠正常工作。
當USB設備連接到Android設備時，我們會收到如下系統廣播數據，通過UsbDevice對象，你可以獲取設備的VID、PID、產品名稱、制造商名稱等基本信息。
UsbDevice[
mName=/dev/bus/usb/002/005,
mVendorId=1008,
mProductId=1694,
mClass=0,
mSubclass=0,
mProtocol=0,
mManufacturerName=HP Inc.,
mProductName=HP Laser 1008a,
mVersion=2.0,
mSerialNumber=CNB1RC683F,
mConfigurations=[
UsbConfiguration[
mId=1,
mName=null,
mAttributes=192,
mMaxPower=1,
mInterfaces=[
UsbInterface[
mId=0,
mAlternateSetting=0,
mName=null,
mClass=7,
mSubclass=1,
mProtocol=2,
mEndpoints=[
UsbEndpoint[mAddress=2,mAttributes=2,mMaxPacketSize=512,mInterval=10]
UsbEndpoint[mAddress=129,mAttributes=2,mMaxPacketSize=512,mInterval=10]
]
UsbInterface[
mId=0,
mAlternateSetting=1,
mName=null,
mClass=7,
mSubclass=1,
mProtocol=4,
mEndpoints=[
UsbEndpoint[mAddress=2,mAttributes=2,mMaxPacketSize=512,mInterval=10]
UsbEndpoint[mAddress=129,mAttributes=2,mMaxPacketSize=512,mInterval=10]
]
UsbInterface[
mId=1,
mAlternateSetting=0,
mName=null,
mClass=255,
mSubclass=4,
mProtocol=1,
mEndpoints=[
UsbEndpoint[mAddress=6,mAttributes=2,mMaxPacketSize=512,mInterval=10]
UsbEndpoint[mAddress=133,mAttributes=2,mMaxPacketSize=512,mInterval=10]
]
UsbInterface[
mId=1,
mAlternateSetting=1,
mName=null,
mClass=7,
mSubclass=1,
mProtocol=4,
mEndpoints=[
UsbEndpoint[mAddress=6,mAttributes=2,mMaxPacketSize=512,mInterval=10]
UsbEndpoint[mAddress=133,mAttributes=2,mMaxPacketSize=512,mInterval=10]
]
]
]VID
（Vendor ID）是USB設備的一個標識符，由USB Implementers Forum（USB-IF）分配給設備制造商的一個16位的十六進制數，用于標識其生產的設備。每個設備制造商都有一個唯一的VID。
在USB設備中，VID與PID（Product ID）一起使用，用于識別和管理設備。當USB設備連接到計算機時，操作系統會檢測設備的VID和PID，并根據這些信息加載相應的驅動程序，確保設備能夠正常工作。
廠商在開發USB產品前，需要從USB-IF取得廠商標識符（Vendor ID）。申請VID的方式包括成為USB-IF會員并繳納年費，或者通過第三方機構進行申請。獲得VID后，廠商可以進行USB測試，并將測試結果連同USB商標許可協議遞交給USB-IF協會進行審核。
PID
（Product ID）是USB設備的一個標識符，用于標識同一制造商生產的不同設備。PID由設備制造商定義，長度通常為8位，由低4位的類型字段和高4位的校驗字段組成。類型字段的不同組合用于標識不同類型的USB數據包，如令牌包、握手包、數據包和特殊包。
在USB通信中，PID字段用于指明數據傳輸的方向、幀開始、數據傳輸的結果以及數據包的奇偶性等。
在USB設備的識別和管理中，VID和PID一起發揮著關鍵作用。當USB設備掛載連接到時，操作系統會檢測設備的VID和PID，根據這些信息加載相應的驅動程序，確保設備能夠正常工作。VID和PID還用于設備管理，包括設備的連接和斷開、設備的狀態監測和控制等。
ADB WiFi中USB連接處理
通用獲取USB設備方法：
UsbManager usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
if (!deviceList.isEmpty()) {
for (Map.Entry<String, UsbDevice> entry : deviceList.entrySet()) {
UsbDevice device = entry.getValue();
int vendorId = device.getVendorId();
int productId = device.getProductId();
String deviceName = device.getDeviceName();
String productName = device.getProductName();
String manufacturerName = device.getManufacturerName();
// 打印設備信息
Log.d("USB設備信息", "Vendor ID: " + vendorId);
Log.d("USB設備信息", "Product ID: " + productId);
Log.d("USB設備信息", "Device Name: " + deviceName);
Log.d("USB設備信息", "Product Name: " + productName);
Log.d("USB設備信息", "Manufacturer: " + manufacturerName);
}
} else {
Log.d("USB設備信息", "沒有USB設備連接.");
}廣播實時監聽USB設備接入拔出：
public class MainActivity extends AppCompatActivity {
private UsbReceiver usbReceiver;
private UsbManager usbManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
usbReceiver = new UsbReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
registerReceiver(usbReceiver, filter);
}
@Override
protected void onResume() {
super.onResume();
registerReceiver(usbReceiver, new IntentFilter(UsbManager.ACTION_USB_PERMISSION));
}
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(usbReceiver);
}
private final class UsbReceiver extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (device != null) {
// 請求USB設備訪問權限
PendingIntent pi = PendingIntent.getBroadcast(context, 0, new Intent(ACTION_USB_PERMISSION), 0);
usbManager.requestPermission(device, pi);
}
} else if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action)) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (device != null) {
// 處理USB設備拔出事件
}
} else if (UsbManager.ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
if (device != null) {
// USB設備權限被授予，可以進行通信了
}
} else {
// 權限被拒絕，處理邏輯
}
}
}
}
}
}ADB WiFi實時監聽USB設備接入處理：
public class ADBControlEntrance {
private static final String TAG = ADBControlEntrance.class.getSimpleName();
private static volatile ADBControlEntrance sInstance;
private UsbManager mUsbManager;
private UsbDevice mUsbDevice;
private AdbCrypto mCrypto;
private AdbConnection mConnection;
private AdbStream mStream;
private final List<TerminalDataListener> mTerminalDataListenerList = Collections.synchronizedList(new ArrayList<>());
private final List<String> mWriteDataList = new ArrayList<>();
private final Object mWriteSyncLock = new Object();
private ReadDataThread mReadDataThread;
private WriteDataThread mWriteDataThread;
private Thread mConnectThread;
private ADBControlEntrance() {
}
public static ADBControlEntrance getInstance() {
if (sInstance == null) {
synchronized (ADBControlEntrance.class) {
if (sInstance == null) {
sInstance = new ADBControlEntrance();
}
}
}
return sInstance;
}
public void init(Context context) {
mUsbManager = (UsbManager) context.getApplicationContext().getSystemService(Context.USB_SERVICE);
try {
mCrypto = AdbCrypto.generateAdbKeyPair(new Base64Impl());
mCrypto.saveAdbKeyPair(new File(context.getFilesDir(), "private_key"), new File(context.getFilesDir(), "public_key"));
} catch (NoSuchAlgorithmException | IOException e) {
Log.e(TAG, "初始化創建密鑰對失敗:", e);
}
mReadDataThread = new ReadDataThread();
mReadDataThread.start();
mWriteDataThread = new WriteDataThread();
mWriteDataThread.start();
//注冊USB廣播
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(Constants.USB_PERMISSION);
intentFilter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
intentFilter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
context.registerReceiver(mUsbDeviceReceiver, intentFilter, Context.RECEIVER_EXPORTED);
} else {
context.registerReceiver(mUsbDeviceReceiver, intentFilter);
}
//遍歷USB設備
HashMap<String, UsbDevice> deviceList = mUsbManager.getDeviceList();
for (UsbDevice device : deviceList.values()) {
if (mUsbManager.hasPermission(device)) {
asyncRefreshConnection(device);
} else {
//請求權限
requestPermission(context, device);
}
}
}
public void addTerminalDataListener(TerminalDataListener terminalDataListener) {
mTerminalDataListenerList.add(terminalDataListener);
}
public void removeTerminalDataListener(TerminalDataListener terminalDataListener) {
mTerminalDataListenerList.remove(terminalDataListener);
}
public void removeAllTerminalDataListener() {
mTerminalDataListenerList.clear();
}
public void release() {
closeConnection(false);
if (mReadDataThread != null) {
mReadDataThread.interrupt();
mReadDataThread = null;
}
if (mWriteDataThread != null) {
mWriteDataThread.interrupt();
mWriteDataThread = null;
}
mTerminalDataListenerList.clear();
}
public boolean isConnected() {
return mConnection != null && mConnection.isConnected();
}
private void asyncRefreshConnection(UsbDevice device) {
closeConnection(true);
if (device == null) return;
UsbInterface usbInterface = null;
for (int index = 0; index < device.getInterfaceCount(); index++) {
UsbInterface interface1 = device.getInterface(index);
if (interface1.getInterfaceClass() == 255 && interface1.getInterfaceSubclass() == 66 && interface1.getInterfaceProtocol() == 1) {
usbInterface = interface1;
break;
}
}
if (usbInterface == null) return;
UsbDeviceConnection deviceConnection = mUsbManager.openDevice(device);
if (deviceConnection.claimInterface(usbInterface, false)) {
UsbChannel usbChannel = new UsbChannel(deviceConnection, usbInterface);
try {
mConnection = AdbConnection.create(usbChannel, mCrypto);
mConnection.connect();
mStream = mConnection.open("shell:");
mUsbDevice = device;
//設備已連接
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceConnect(0);
}
Log.d(TAG, "USB ADB連接:成功");
} catch (IOException | InterruptedException e) {
Log.e(TAG, "USB ADB連接", e);
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceDisConnect();
}
}
} else {
deviceConnection.close();
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceDisConnect();
}
}
}
public void asyncRefreshConnection(String host) {
closeConnection(false);
if (TextUtils.isEmpty(host)) return;
if (mConnectThread != null) {
mConnectThread.interrupt();
mConnectThread = null;
}
mConnectThread = new Thread(new Runnable() {
@Override
public void run() {
try {
Socket socket = new Socket(host, 5555);
TcpChannel tcpChannel = new TcpChannel(socket);
mConnection = AdbConnection.create(tcpChannel, mCrypto);
mConnection.connect();
mStream = mConnection.open("shell:");
//設備已連接
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceConnect(1);
}
Log.d(TAG, "TCP ADB連接:成功");
} catch (IOException | InterruptedException e) {
Log.e(TAG, "TCP ADB連接:", e);
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceDisConnect();
}
}
}
});
mConnectThread.start();
}
private class ReadDataThread extends Thread {
@Override
public void run() {
super.run();
while (!interrupted()) {
asyncReadBuffer();
}
}
}
private void asyncReadBuffer() {
if (mConnection != null && mStream != null) {
while (!mStream.isClosed()) {
try {
byte[] buffer = mStream.read();
String output = new String(buffer, StandardCharsets.US_ASCII);
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onTerminalOutput(output);
}
} catch (InterruptedException | IOException e) {
Log.e(TAG, "讀取終端數據:", e);
}
}
}
}
private class WriteDataThread extends Thread {
@Override
public void run() {
super.run();
while (!isInterrupted()) {
if (mWriteDataList.isEmpty()) {
try {
synchronized (mWriteSyncLock) {
mWriteSyncLock.wait();
}
} catch (InterruptedException e) {
Log.e(TAG, "發送終端數據:", e);
}
} else {
String command = mWriteDataList.remove(0);
try {
//發送命令
mStream.write((command + "\n").getBytes(StandardCharsets.UTF_8));
} catch (IOException | InterruptedException e) {
Log.e(TAG, "發送終端數據:", e);
}
}
}
}
}
public boolean asyncWriteBuffer(String command) {
if (TextUtils.isEmpty(command)) return false;
if (mStream == null || mStream.isClosed()) return false;
mWriteDataList.add(command);
synchronized (mWriteSyncLock) {
mWriteSyncLock.notify();
}
return true;
}
public void closeConnection(boolean callback) {
//關閉連接
if (mConnection != null) {
try {
mConnection.close();
} catch (IOException e) {
Log.e(TAG, "關閉USB ADB連接:", e);
}
mConnection = null;
}
if (callback) {
for (TerminalDataListener terminalDataListener : mTerminalDataListenerList) {
terminalDataListener.onDeviceDisConnect();
}
}
}
private void requestPermission(Context context, UsbDevice device) {
mUsbManager.requestPermission(device, PendingIntent.getBroadcast(context.getApplicationContext(), 0, new Intent(Constants.USB_PERMISSION), PendingIntent.FLAG_IMMUTABLE));
}
private final BroadcastReceiver mUsbDeviceReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(intent.getAction())) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (device != null && mUsbDevice != null) {
//斷開連接的和當前連接的是同一個設備 斷開連接
if (mUsbDevice.getDeviceName().equals(device.getDeviceName())) {
//關閉連接
closeConnection(true);
}
}
}
if (UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(intent.getAction())) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (device != null && mUsbDevice != null) {
//連接的和當前連接的不是同一個設備
if (!mUsbDevice.getDeviceName().equals(device.getDeviceName())) {
//開始連接
if (mUsbManager.hasPermission(device)) {
asyncRefreshConnection(device);
} else {
//請求權限
requestPermission(context, device);
}
}
}
}
if (Constants.USB_PERMISSION.equals(intent.getAction())) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
//開始連接
if (mUsbManager.hasPermission(device)) {
asyncRefreshConnection(device);
} else {
//請求權限
requestPermission(context, device);
}
}
}
};
}責任編輯：趙寧寧
來源：
沐雨花飛蝶
