xref: /openbmc/phosphor-fan-presence/control/json/fan.cpp (revision b5fda8ddce801865020847b75d12712b1bed1c37)
1 /**
2  * Copyright © 2022 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 "fan.hpp"
17 
18 #include "sdbusplus.hpp"
19 
20 #include <nlohmann/json.hpp>
21 #include <phosphor-logging/lg2.hpp>
22 #include <sdbusplus/bus.hpp>
23 
24 #include <format>
25 
26 namespace phosphor::fan::control::json
27 {
28 
29 using json = nlohmann::json;
30 
31 constexpr auto FAN_SENSOR_PATH = "/xyz/openbmc_project/sensors/fan_tach/";
32 constexpr auto FAN_TARGET_PROPERTY = "Target";
33 
Fan(const json & jsonObj)34 Fan::Fan(const json& jsonObj) :
35     ConfigBase(jsonObj), _bus(util::SDBusPlus::getBus())
36 {
37     setInterface(jsonObj);
38     setSensors(jsonObj);
39     setZone(jsonObj);
40 }
41 
setInterface(const json & jsonObj)42 void Fan::setInterface(const json& jsonObj)
43 {
44     if (!jsonObj.contains("target_interface"))
45     {
46         lg2::error("Missing required fan sensor target interface", "JSON",
47                    jsonObj.dump());
48         throw std::runtime_error(
49             "Missing required fan sensor target interface");
50     }
51     _interface = jsonObj["target_interface"].get<std::string>();
52 }
53 
setSensors(const json & jsonObj)54 void Fan::setSensors(const json& jsonObj)
55 {
56     if (!jsonObj.contains("sensors"))
57     {
58         lg2::error("Missing required fan sensors list", "JSON", jsonObj.dump());
59         throw std::runtime_error("Missing required fan sensors list");
60     }
61     std::string path;
62     for (const auto& sensor : jsonObj["sensors"])
63     {
64         if (!jsonObj.contains("target_path"))
65         {
66             // If target_path is not set in configuration,
67             // it is default to /xyz/openbmc_project/sensors/fan_tach/
68             path = FAN_SENSOR_PATH + sensor.get<std::string>();
69         }
70         else
71         {
72             path = jsonObj["target_path"].get<std::string>() +
73                    sensor.get<std::string>();
74         }
75 
76         std::string service;
77         int attempts = 0;
78         constexpr int maxAttempts = 5;
79         while (true)
80         {
81             try
82             {
83                 service = util::SDBusPlus::getService(_bus, path, _interface);
84                 break;
85             }
86             catch (const std::exception&)
87             {
88                 lg2::warning("No service for {PATH} {INTERFACE}", "PATH", path,
89                              "INTERFACE", _interface);
90                 attempts++;
91                 if (attempts == maxAttempts)
92                 {
93                     lg2::error("Giving up");
94                     throw;
95                 }
96                 lg2::info("Retrying");
97                 std::this_thread::sleep_for(std::chrono::seconds(2));
98             }
99         }
100         _sensors[path] = service;
101     }
102     // All sensors associated with this fan are set to the same target,
103     // so only need to read target property from one of them
104     if (!path.empty())
105     {
106         _target = util::SDBusPlus::getProperty<uint64_t>(
107             _bus, _sensors.at(path), path, _interface, FAN_TARGET_PROPERTY);
108     }
109 }
110 
setZone(const json & jsonObj)111 void Fan::setZone(const json& jsonObj)
112 {
113     if (!jsonObj.contains("zone"))
114     {
115         lg2::error("Missing required fan zone", "JSON", jsonObj.dump());
116         throw std::runtime_error("Missing required fan zone");
117     }
118     _zone = jsonObj["zone"].get<std::string>();
119 }
120 
setTarget(uint64_t target)121 void Fan::setTarget(uint64_t target)
122 {
123     if ((_target == target) || !_lockedTargets.empty())
124     {
125         return;
126     }
127 
128     for (const auto& sensor : _sensors)
129     {
130         auto value = target;
131         try
132         {
133             util::SDBusPlus::setProperty<uint64_t>(
134                 _bus, sensor.second, sensor.first, _interface,
135                 FAN_TARGET_PROPERTY, std::move(value));
136         }
137         catch (const sdbusplus::exception_t&)
138         {
139             throw util::DBusPropertyError{
140                 std::format("Failed to set target for fan {}", _name).c_str(),
141                 sensor.second, sensor.first, _interface, FAN_TARGET_PROPERTY};
142         }
143     }
144     _target = target;
145 }
146 
lockTarget(uint64_t target)147 void Fan::lockTarget(uint64_t target)
148 {
149     // if multiple locks, take highest, else allow only the
150     // first lock to lower the target
151     if (target >= _target || _lockedTargets.empty())
152     {
153         // setTarget wont work if any locked targets exist
154         decltype(_lockedTargets) temp;
155         _lockedTargets.swap(temp);
156 
157         setTarget(target);
158         _lockedTargets.swap(temp);
159     }
160 
161     _lockedTargets.push_back(target);
162 }
163 
unlockTarget(uint64_t target)164 void Fan::unlockTarget(uint64_t target)
165 {
166     // find and remove the requested lock
167     auto itr(std::find_if(
168         _lockedTargets.begin(), _lockedTargets.end(),
169         [target](auto lockedTarget) { return target == lockedTarget; }));
170 
171     if (_lockedTargets.end() != itr)
172     {
173         _lockedTargets.erase(itr);
174 
175         // if additional locks, re-lock at next-highest target
176         if (!_lockedTargets.empty())
177         {
178             itr =
179                 std::max_element(_lockedTargets.begin(), _lockedTargets.end());
180 
181             // setTarget wont work if any locked targets exist
182             decltype(_lockedTargets) temp;
183             _lockedTargets.swap(temp);
184             setTarget(*itr);
185             _lockedTargets.swap(temp);
186         }
187     }
188 }
189 
190 } // namespace phosphor::fan::control::json
191