1 /* 2 * Copyright (C) 2017 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 package com.android.server.usb.descriptors; 17 18 import com.android.server.usb.descriptors.report.ReportCanvas; 19 20 /** 21 * @hide 22 * An audio class-specific Header descriptor. 23 * see Audio20.pdf section 4.7.2 Class-Specific AC Interface Descriptor 24 */ 25 public final class Usb20ACHeader extends UsbACHeaderInterface { 26 private static final String TAG = "Usb20ACHeader"; 27 28 private byte mCategory; // 5:1 Constant, indicating the primary use of this audio function. 29 // See audio20.pdf Appendix A.7, Audio Function Category Codes. 30 private byte mControls; // 8:1 See audio20.pdf Table 4-5. 31 32 public Usb20ACHeader(int length, byte type, byte subtype, int subclass, int spec) { 33 super(length, type, subtype, subclass, spec); 34 } 35 36 public byte getCategory() { 37 return mCategory; 38 } 39 40 public byte getControls() { 41 return mControls; 42 } 43 44 @Override 45 public int parseRawDescriptors(ByteStream stream) { 46 mCategory = stream.getByte(); 47 mTotalLength = stream.unpackUsbShort(); 48 mControls = stream.getByte(); 49 50 return mLength; 51 } 52 53 @Override 54 public void report(ReportCanvas canvas) { 55 super.report(canvas); 56 57 canvas.openList(); 58 canvas.writeListItem("Category: " + ReportCanvas.getHexString(getCategory())); 59 canvas.writeListItem("Controls: " + ReportCanvas.getHexString(getControls())); 60 canvas.closeList(); 61 } 62 } 63
