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 17 18 package com.android.future.usb; 19 20 import android.app.PendingIntent; 21 import android.content.Context; 22 import android.content.Intent; 23 import android.hardware.usb.IUsbManager; 24 import android.os.IBinder; 25 import android.os.ParcelFileDescriptor; 26 import android.os.RemoteException; 27 import android.os.ServiceManager; 28 import android.util.Log; 29 30 /** 31 * This is a wrapper class for the USB Manager to support USB accessories. 32 * 33 * <p>You can obtain an instance of this class by calling {@link #getInstance} 34 * 35 */ 36 public class UsbManager { 37 private static final String TAG = "UsbManager"; 38 39 /** 40 * Broadcast Action: A broadcast for USB accessory attached event. 41 * 42 * This intent is sent when a USB accessory is attached. 43 * Call {@link #getAccessory(android.content.Intent)} to retrieve the 44 * {@link com.google.android.usb.UsbAccessory} for the attached accessory. 45 */ 46 public static final String ACTION_USB_ACCESSORY_ATTACHED = 47 "android.hardware.usb.action.USB_ACCESSORY_ATTACHED"; 48 49 /** 50 * Broadcast Action: A broadcast for USB accessory detached event. 51 * 52 * This intent is sent when a USB accessory is detached. 53 * Call {@link #getAccessory(android.content.Intent)} to retrieve the 54 * {@link com.google.android.usb.UsbAccessory} for the attached accessory that was detached. 55 */ 56 public static final String ACTION_USB_ACCESSORY_DETACHED = 57 "android.hardware.usb.action.USB_ACCESSORY_DETACHED"; 58 59 /** 60 * Name of extra added to the {@link android.app.PendingIntent} 61 * passed into {#requestPermission} or {#requestPermission} 62 * containing a boolean value indicating whether the user granted permission or not. 63 */ 64 public static final String EXTRA_PERMISSION_GRANTED = "permission"; 65 66 private final Context mContext; 67 private final IUsbManager mService; 68 69 private UsbManager(Context context, IUsbManager service) { 70 mContext = context; 71 mService = service; 72 } 73 74 /** 75 * Returns a new instance of this class. 76 * 77 * @param context the caller's {@link android.content.Context} 78 * @return UsbManager instance. 79 */ 80 public static UsbManager getInstance(Context context) { 81 IBinder b = ServiceManager.getService(Context.USB_SERVICE); 82 return new UsbManager(context, IUsbManager.Stub.asInterface(b)); 83 } 84 85 /** 86 * Returns the {@link com.google.android.usb.UsbAccessory} for 87 * a {@link #ACTION_USB_ACCESSORY_ATTACHED} or {@link #ACTION_USB_ACCESSORY_ATTACHED} 88 * broadcast Intent. This can also be used to retrieve the accessory from the result 89 * of a call to {#requestPermission}. 90 * 91 * @return UsbAccessory for the intent. 92 */ 93 public static UsbAccessory getAccessory(Intent intent) { 94 android.hardware.usb.UsbAccessory accessory = 95 intent.getParcelableExtra(android.hardware.usb.UsbManager.EXTRA_ACCESSORY); 96 if (accessory == null) { 97 return null; 98 } else { 99 return new UsbAccessory(accessory); 100 } 101 } 102 103 /** 104 * Returns a list of currently attached USB accessories. 105 * (in the current implementation there can be at most one) 106 * 107 * @return list of USB accessories, or null if none are attached. 108 */ 109 public UsbAccessory[] getAccessoryList() { 110 try { 111 android.hardware.usb.UsbAccessory accessory = mService.getCurrentAccessory(); 112 if (accessory == null) { 113 return null; 114 } else { 115 return new UsbAccessory[] { new UsbAccessory(accessory) }; 116 } 117 } catch (RemoteException e) { 118 Log.e(TAG, "RemoteException in getAccessoryList" , e); 119 return null; 120 } 121 } 122 123 /** 124 * Opens a file descriptor for reading and writing data to the USB accessory. 125 * 126 * @param accessory the USB accessory to open 127 * @return file descriptor, or null if the accessor could not be opened. 128 */ 129 public ParcelFileDescriptor openAccessory(UsbAccessory accessory) { 130 try { 131 return mService.openAccessory(new android.hardware.usb.UsbAccessory( 132 accessory.getManufacturer(),accessory.getModel(), 133 accessory.getDescription(), accessory.getVersion(), 134 accessory.getUri(), accessory.getSerial())); 135 } catch (RemoteException e) { 136 Log.e(TAG, "RemoteException in openAccessory" , e); 137 return null; 138 } 139 } 140 141 /** 142 * Returns true if the caller has permission to access the accessory. 143 * Permission might have been granted temporarily via 144 * {@link #requestPermission} or 145 * by the user choosing the caller as the default application for the accessory. 146 * 147 * @param accessory to check permissions for 148 * @return true if caller has permission 149 */ 150 public boolean hasPermission(UsbAccessory accessory) { 151 try { 152 return mService.hasAccessoryPermission(new android.hardware.usb.UsbAccessory( 153 accessory.getManufacturer(),accessory.getModel(), 154 accessory.getDescription(), accessory.getVersion(), 155 accessory.getUri(), accessory.getSerial())); 156 } catch (RemoteException e) { 157 Log.e(TAG, "RemoteException in hasPermission", e); 158 return false; 159 } 160 } 161 162 /** 163 * Requests temporary permission for the given package to access the accessory. 164 * This may result in a system dialog being displayed to the user 165 * if permission had not already been granted. 166 * Success or failure is returned via the {@link android.app.PendingIntent} pi. 167 * The boolean extra {@link #EXTRA_PERMISSION_GRANTED} will be attached to the 168 * PendingIntent to indicate success or failure. 169 * If successful, this grants the caller permission to access the device only 170 * until the device is disconnected. 171 * 172 * @param accessory to request permissions for 173 * @param pi PendingIntent for returning result 174 */ 175 public void requestPermission(UsbAccessory accessory, PendingIntent pi) { 176 try { 177 mService.requestAccessoryPermission(new android.hardware.usb.UsbAccessory( 178 accessory.getManufacturer(),accessory.getModel(), 179 accessory.getDescription(), accessory.getVersion(), 180 accessory.getUri(), accessory.getSerial()), 181 mContext.getPackageName(), pi); 182 } catch (RemoteException e) { 183 Log.e(TAG, "RemoteException in requestPermission", e); 184 } 185 } 186 } 187
