commit 3ec41c53ac70b69b023d7ed92bd2908104d7cdf4
author Bruce Mitchell <bruce.mitchell@linux.vnet.ibm.com> Fri Dec 10 16:05:17 2021 -0600
committer Ed Tanous <ed@tanous.net> Mon Jan 10 17:45:22 2022 +0000
tree 56ec3a47037ae0edecf692a879d332782c65d180
parent 4786334f3eab8ab7f4d5ff8e94cf507b4a29c203

Add reporting of Relative Humidity for Hwmon

By checking for IIO devies of in_humidityrelative_input or
in_humidityrelative_raw we add to the reading of those devices too.
Also the units for "Percent" now have become overloaded, as humidity
is "Percent" Relative Humidity and not a a Utilization. I believe
Utilization should NOT be a "Percent" but a fraction from 0 to 1.

Tested: on Rainier's Blyth and Everest's Storm King Op Panels
busctl introspect --no-pager xyz.openbmc_project.HwmonTempSensor \
/xyz/openbmc_project/sensors/humidity/Relative_Humidity
Results consistent with location of the systems.

Signed-off-by: Bruce Mitchell <bruce.mitchell@linux.vnet.ibm.com>
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I62c2464177542e7a2234f277be30d4fa4a849381

src/HwmonTempMain.cpp

diff --git a/src/HwmonTempMain.cpp b/src/HwmonTempMain.cpp
index dbccd27..b6bf910 100644
--- a/src/HwmonTempMain.cpp
+++ b/src/HwmonTempMain.cpp
@@ -41,6 +41,9 @@
 static constexpr double maxValuePressure = 120000; // Pascals
 static constexpr double minValuePressure = 30000;  // Pascals
 
+static constexpr double maxValueRelativeHumidity = 100; // PercentRH
+static constexpr double minValueRelativeHumidity = 0;   // PercentRH
+
 static constexpr double maxValueTemperature = 127;  // DegreesC
 static constexpr double minValueTemperature = -128; // DegreesC
 
@@ -130,6 +133,16 @@
         tmpSensorParameters.typeName = "pressure";
         tmpSensorParameters.units = sensor_paths::unitPascals;
     }
+    else if (path.filename() == "in_humidityrelative_input" ||
+             path.filename() == "in_humidityrelative_raw")
+    {
+        tmpSensorParameters.minValue = minValueRelativeHumidity;
+        tmpSensorParameters.maxValue = maxValueRelativeHumidity;
+        // Relative Humidity are read in milli-percent, we need percent.
+        tmpSensorParameters.scaleValue *= 0.001;
+        tmpSensorParameters.typeName = "humidity";
+        tmpSensorParameters.units = "PercentRH";
+    }
     else
     {
         // Temperatures are read in milli degrees Celsius,
@@ -166,6 +179,7 @@
             fs::path root("/sys/bus/iio/devices");
             findFiles(root, R"(in_temp\d*_(input|raw))", paths);
             findFiles(root, R"(in_pressure\d*_(input|raw))", paths);
+            findFiles(root, R"(in_humidityrelative\d*_(input|raw))", paths);
             findFiles(fs::path("/sys/class/hwmon"), R"(temp\d+_input)", paths);
 
             if (paths.empty())
@@ -270,7 +284,8 @@
 
                 // Temperature has "Name", pressure has "Name1"
                 auto findSensorName = baseConfigMap->find("Name");
-                if (thisSensorParameters.typeName == "pressure")
+                if (thisSensorParameters.typeName == "pressure" ||
+                    thisSensorParameters.typeName == "humidity")
                 {
                     findSensorName = baseConfigMap->find("Name1");
                 }