1 /*
2  * Copyright (C) 2014 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 package com.android.server.hdmi;
18 
19 /**
20  * Class that holds together the constants that may require per-product configuration.
21  */
22 final class HdmiConfig {
23 
24     // Default timeout for the incoming command to arrive in response to a request.
25     static final int TIMEOUT_MS = 2000;
26 
27     // IRT(Initiator Repetition Time) in millisecond as recommended in the standard.
28     // Outgoing UCP commands, when in 'Press and Hold' mode, should be this much apart
29     // from the adjacent one so as not to place unnecessarily heavy load on the CEC line.
30     static final int IRT_MS = 300;
31 
32     // Number of retries for polling each device in device discovery phase after TV powers on
33     // or HDMI control is enabled.
34     static final int DEVICE_POLLING_RETRY = 1;
35 
36     // Number of retries for polling each device in periodic check (hotplug detection).
37     static final int HOTPLUG_DETECTION_RETRY = 1;
38 
39     // Number of retries for polling each device in address allocation mechanism.
40     static final int ADDRESS_ALLOCATION_RETRY = 3;
41 
42     // Number of retries for sendCommand in actions related to new device discovery.
43     // Number 5 comes from 10 seconds for Chromecast preparation time.
44     static final int TIMEOUT_RETRY = 5;
45 
46     // CEC spec said that it should try retransmission at least once.
47     // The actual number of send request for a single command will be at most
48     // RETRANSMISSION_COUNT + 1. Note that it affects only to normal commands
49     // and polling message for logical address allocation and device discovery
50     // action. They will have their own retransmission count.
51     static final int RETRANSMISSION_COUNT = 1;
52 
53     // Do not export the CEC devices connected to a legacy HDMI switch. The usage of legacy
54     // (non-CEC) switches is deprecated. They stop the correct operation of many mandatory
55     // CEC features. If set to true, do not pass the list of CEC devices behind the legacy
56     // switch since they won't be under control from TV.
57     static final boolean HIDE_DEVICES_BEHIND_LEGACY_SWITCH = true;
58 
HdmiConfig()59     private HdmiConfig() { /* cannot be instantiated */ }
60 }
61