1 /**
2 * Copyright © 2017 IBM Corporation
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 #include "fallback.hpp"
17
18 #include "fan.hpp"
19 #include "psensor.hpp"
20
21 #include <phosphor-logging/log.hpp>
22
23 #include <algorithm>
24 #include <format>
25
26 namespace phosphor
27 {
28 namespace fan
29 {
30 namespace presence
31 {
32
stateChanged(bool present,PresenceSensor &)33 void Fallback::stateChanged(bool present, PresenceSensor& /*sensor*/)
34 {
35 if (!present)
36 {
37 // Starting with the first backup, find the first
38 // sensor that reports the fan as present, if any.
39 auto it = std::find_if(std::next(activeSensor), sensors.end(),
40 [](auto& s) { return s.get().present(); });
41
42 if (it != sensors.end())
43 {
44 // A backup sensor disagrees with the active sensor.
45 // Switch to the backup.
46 activeSensor->get().stop();
47 present = it->get().start();
48
49 while (activeSensor != it)
50 {
51 // Callout the broken sensors.
52 activeSensor->get().fail();
53 ++activeSensor;
54 }
55 phosphor::logging::log<phosphor::logging::level::INFO>(
56 std::format("Using backup presence sensor for fan {}",
57 std::get<1>(fan))
58 .c_str());
59 activeSensor = it;
60 }
61 }
62
63 setPresence(fan, present);
64
65 if (eepromDevice)
66 {
67 if (present)
68 {
69 eepromDevice->bind();
70 }
71 else
72 {
73 eepromDevice->unbind();
74 }
75 }
76 }
77
monitor()78 void Fallback::monitor()
79 {
80 // Find the first sensor that says the fan is present
81 // and set it as the active sensor.
82 activeSensor = std::find_if(sensors.begin(), sensors.end(), [](auto& s) {
83 return s.get().present();
84 });
85 if (activeSensor == sensors.end())
86 {
87 // The first sensor is working or all sensors
88 // agree the fan isn't present. Use the first sensor.
89 activeSensor = sensors.begin();
90 }
91
92 if (activeSensor != sensors.begin())
93 {
94 phosphor::logging::log<phosphor::logging::level::INFO>(
95 std::format("Using backup presence sensor for fan {}",
96 std::get<1>(fan))
97 .c_str());
98 }
99
100 // Callout the broken sensors.
101 auto it = sensors.begin();
102 while (it != activeSensor)
103 {
104 it->get().fail();
105 ++it;
106 }
107
108 // Start the active sensor and set the initial state.
109 setPresence(fan, activeSensor->get().start());
110 }
111
112 } // namespace presence
113 } // namespace fan
114 } // namespace phosphor
115