From 2b3db618a00a1360d7a61cf0e712e1c50764297f Mon Sep 17 00:00:00 2001
From: Matthew Barth <msbarth@us.ibm.com>
Date: Wed, 25 Oct 2017 10:56:51 -0500
Subject: Init zone target speed to current target speed

Whenever fan control (control mode) is started, the target speed for
each zone should be initialized to the currently set target speed.

In the case where a watchdog has triggered the fans to full speed
and the target speed does not reflect this, the proper set of set speed
events should be configured. In this case, an event could be defined to
use the current tach feedback to adjust the target speed prior to
account for the real state of the fan speeds.

Change-Id: I538644ffc83a6e01469174304d393c889038d066
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
---
 control/fan.cpp  | 17 ++++++++++++++++-
 control/fan.hpp  | 15 +++++++++++++++
 control/zone.cpp |  5 +++++
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/control/fan.cpp b/control/fan.cpp
index fcbf4f8..1326451 100644
--- a/control/fan.cpp
+++ b/control/fan.cpp
@@ -20,6 +20,7 @@
 #include <string>
 #include "fan.hpp"
 #include "utility.hpp"
+#include "sdbusplus.hpp"
 
 namespace phosphor
 {
@@ -43,10 +44,22 @@ Fan::Fan(sdbusplus::bus::bus& bus, const FanDefinition& def):
     _bus(bus),
     _name(std::get<fanNamePos>(def))
 {
+    std::string path;
     auto sensors = std::get<sensorListPos>(def);
     for (auto& s : sensors)
     {
-        _sensors.emplace_back(FAN_SENSOR_PATH + s);
+        path = FAN_SENSOR_PATH + s;
+        _sensors.emplace_back(path);
+    }
+    // All sensors associated with this fan are set to same target speed,
+    // so only need to read target property from one.
+    if (!path.empty())
+    {
+        _targetSpeed = util::SDBusPlus::getProperty<uint64_t>(
+                bus,
+                path,
+                FAN_SENSOR_CONTROL_INTF,
+                FAN_TARGET_PROPERTY);
     }
 }
 
@@ -84,6 +97,8 @@ void Fan::setSpeed(uint64_t speed)
             elog<InternalFailure>();
         }
     }
+
+    _targetSpeed = speed;
 }
 
 }
diff --git a/control/fan.hpp b/control/fan.hpp
index e23d44e..6975248 100644
--- a/control/fan.hpp
+++ b/control/fan.hpp
@@ -46,6 +46,16 @@ class Fan
          */
         void setSpeed(uint64_t speed);
 
+        /**
+         * @brief Get the current fan target speed
+         *
+         * @return - The target speed of the fan
+         */
+        inline auto getTargetSpeed() const
+        {
+            return _targetSpeed;
+        }
+
     private:
 
         /**
@@ -71,6 +81,11 @@ class Fan
          * Vector of hwmon sensors for the rotors
          */
         std::vector<std::string> _sensors;
+
+        /**
+         * Target speed for this fan
+         */
+        uint64_t _targetSpeed;
 };
 
 
diff --git a/control/zone.cpp b/control/zone.cpp
index 418b3ba..cb8ebfa 100644
--- a/control/zone.cpp
+++ b/control/zone.cpp
@@ -60,6 +60,11 @@ Zone::Zone(Mode mode,
     // Do not enable set speed events when in init mode
     if (mode != Mode::init)
     {
+        // Update target speed to current zone target speed
+        if (!_fans.empty())
+        {
+            _targetSpeed = _fans.front()->getTargetSpeed();
+        }
         // Setup signal trigger for set speed events
         for (auto& event : std::get<setSpeedEventsPos>(def))
         {
-- 
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