From febe200fdf9115bd327a86ad621e963def1b5f09 Mon Sep 17 00:00:00 2001
From: Cody Smith <scody@google.com>
Date: Fri, 18 Feb 2022 13:20:45 +0000
Subject: [PATCH] Feature: Add association interfaces to a target EM

This change gives the `gpiopresence` daemon in `dbus-sensors`
the ability to, upon request via configuration EM, generate am
`xyz.openbmc_project.Association.Definitions` object, which is
used by the Object Mapper to generate associations between two
dbus interfaces.

As `gpiopresence` is unaware of what dbus interfaces may or may
not be probing for the interface it generates, it is left to
the user configuring `gpiopresence` to specify the association
via the `AssociationPath`, `AssociationForward`, and the
`AssociationReverse` fields in `GPIOStatus`.

Once set these will equate to the three string values in
`xyz.openbmc_project.Association.Definitions`.

Tested:
Add EM fields to an existing `GPIOStatus` object.
Check that an association is created by `gpiopresence`
as specified.

Patch Tracking Bug: b/232034841
Upstream info / review: https://gerrit.openbmc.org/c/openbmc/dbus-sensors/+/51360
Upstream-Status: Submitted
Justification: In review

Signed-off-by: Cody Smith <scody@google.com>
In-Review: https://gerrit.openbmc-project.xyz/c/openbmc/dbus-sensors/+/51360/12
Change-Id: I0572d124a8e9b9fedbdfb30d41fe399e005f5c03
---
 include/GPIOPresenceSensor.hpp | 17 +++++-
 src/GPIOPresenceSensor.cpp     |  4 +-
 src/GPIOPresenceSensorMain.cpp | 94 +++++++++++++++++++++++++++++-----
 3 files changed, 101 insertions(+), 14 deletions(-)

diff --git a/include/GPIOPresenceSensor.hpp b/include/GPIOPresenceSensor.hpp
index a9f49a0..fa32a20 100644
--- a/include/GPIOPresenceSensor.hpp
+++ b/include/GPIOPresenceSensor.hpp
@@ -31,6 +31,11 @@ static constexpr inline const char* propertyGpioLine = "GpioLine";
 static constexpr inline const char* propertyPolarity = "Polarity";
 static constexpr inline const char* propertyPresent = "Present";
 static constexpr inline const char* propertyPollRate = "PollRate";
+static constexpr inline const char* propertyAssociationPath = "AssociationPath";
+static constexpr inline const char* propertyAssociationForward =
+    "AssociationForward";
+static constexpr inline const char* propertyAssociationReverse =
+    "AssociationReverse";
 } // namespace Properties

 namespace interfaces
@@ -50,8 +55,15 @@ struct Config
     bool activeLow;
     // Presence signal.
     bool present;
-    // Update loop polling rate.
+    // (Optional) Update loop polling rate.
     int pollRate;
+    // (Optional) Association
+    bool generateAssociation;
+    std::string associationPath;
+    std::string associationForward;
+    std::string associationReverse;
+    // (Internal) Parent path
+    std::string parentPath;
 };

 // Actively listen to the config information from EntityManager and calls the
@@ -65,9 +77,11 @@ class GPIOPresence

     // Add a dbus object to the reference list.
     // @params statusIfc: pointer to object status interface.
+    // @params associationIfc: Optional pointer to object association interface
     // @params objPath: the dbus object path.
     // @params config: EM config
     void addObj(std::unique_ptr<sdbusplus::asio::dbus_interface> statusIfc,
+                std::unique_ptr<sdbusplus::asio::dbus_interface> associationIfc,
                 std::string_view objPath, const Config& config);

     // Remove a object from the object reference list.
@@ -89,6 +103,7 @@ class GPIOPresence
     struct ObjIfaces
     {
         std::unique_ptr<sdbusplus::asio::dbus_interface> statusIfc;
+        std::unique_ptr<sdbusplus::asio::dbus_interface> associationIfc;
         Config config;
     };

diff --git a/src/GPIOPresenceSensor.cpp b/src/GPIOPresenceSensor.cpp
index 870b4b4..2d48491 100644
--- a/src/GPIOPresenceSensor.cpp
+++ b/src/GPIOPresenceSensor.cpp
@@ -26,10 +26,12 @@ int GPIOPresence::readLine(std::string_view lineLabel)

 void GPIOPresence::addObj(
     std::unique_ptr<sdbusplus::asio::dbus_interface> statusIfc,
+    std::unique_ptr<sdbusplus::asio::dbus_interface> associationIfc,
     std::string_view objPath, const Config& config)
 {
     std::cerr << "New objPath added " << objPath << std::endl;
-    objIfaces[std::string(objPath)] = {std::move(statusIfc), config};
+    objIfaces[std::string(objPath)] = {std::move(statusIfc),
+                                       std::move(associationIfc), config};
 }

 void GPIOPresence::removeObj(std::string_view objPath)
diff --git a/src/GPIOPresenceSensorMain.cpp b/src/GPIOPresenceSensorMain.cpp
index 8b22d25..f556900 100644
--- a/src/GPIOPresenceSensorMain.cpp
+++ b/src/GPIOPresenceSensorMain.cpp
@@ -1,8 +1,10 @@
 #include "Utils.hpp"

 #include <GPIOPresenceSensor.hpp>
+#include <sdbusplus/bus/match.hpp>

 #include <iostream>
+#include <utility>

 namespace gpiopresencesensing
 {
@@ -15,7 +17,7 @@ using OnInterfaceRemovedCallback = std::function<void(std::string_view)>;

 // Helper function to convert dbus property to struct
 // @param[in] properties: dbus properties
-Config getConfig(const SensorBaseConfigMap& properties)
+Config getConfig(const SensorBaseConfigMap& properties, std::string parentPath)
 {
     auto name = loadVariant<std::string>(properties, Properties::propertyName);
     auto gpioLine =
@@ -31,8 +33,48 @@ Config getConfig(const SensorBaseConfigMap& properties)
         pollRate =
             loadVariant<uint32_t>(properties, Properties::propertyPollRate);
     }
-    return {name, gpioLine, polarity == "active_low",
-            /*present*/ false, pollRate};
+
+    // Optional Association
+    bool generateAssociation = false;
+    std::string associationForward = "";
+    std::string associationReverse = "";
+    std::string associationPath = "";
+
+    auto propertyAssociationPath =
+        properties.find(Properties::propertyAssociationPath);
+    if (propertyAssociationPath != properties.end())
+    {
+        associationPath = loadVariant<std::string>(
+            properties, Properties::propertyAssociationPath);
+
+        auto propertyAssociationForward =
+            properties.find(Properties::propertyAssociationForward);
+        if (propertyAssociationForward != properties.end())
+        {
+            associationForward = loadVariant<std::string>(
+                properties, Properties::propertyAssociationForward);
+
+            auto propertyAssociationReverse =
+                properties.find(Properties::propertyAssociationReverse);
+            if (propertyAssociationReverse != properties.end())
+            {
+                associationReverse = loadVariant<std::string>(
+                    properties, Properties::propertyAssociationReverse);
+                generateAssociation = true;
+            }
+        }
+    }
+
+    return {name,
+            gpioLine,
+            polarity == "active_low",
+            /*present*/ false,
+            pollRate,
+            generateAssociation,
+            associationPath,
+            associationForward,
+            associationReverse,
+            std::move(parentPath)};
 }

 void setupInterfaceAdded(sdbusplus::asio::connection* conn,
@@ -49,7 +91,7 @@ void setupInterfaceAdded(sdbusplus::asio::connection* conn,
             Config config;
             try
             {
-                config = getConfig(found->second);
+                config = getConfig(found->second, objPath.parent_path());
                 callback(objPath.str, found->first, config);
             }
             catch (std::exception& e)
@@ -62,23 +104,24 @@ void setupInterfaceAdded(sdbusplus::asio::connection* conn,

     // call the user callback for all the device that is already available
     conn->async_method_call(
-        [cb](const boost::system::error_code ec,
-             ManagedObjectType managedObjs) {
+        [callback = cb](const boost::system::error_code ec,
+                        ManagedObjectType managedObjs) {
         if (ec)
         {
             return;
         }
         for (auto& obj : managedObjs)
         {
-            auto& item = obj.second;
+            SensorData& item = obj.second;
+
             auto found = item.find(interfaces::emGPIOCableSensingIfc);
             if (found != item.end())
             {
                 Config config;
                 try
                 {
-                    config = getConfig(found->second);
-                    cb(obj.first.str, found->first, config);
+                    config = getConfig(found->second, obj.first.parent_path());
+                    callback(obj.first.str, found->first, config);
                 }
                 catch (std::exception& e)
                 {
@@ -103,7 +146,7 @@ void setupInterfaceRemoved(sdbusplus::asio::connection* conn,
                            OnInterfaceRemovedCallback&& cb)
 {
     // Listen to the interface removed event.
-    std::function<void(sdbusplus::message::message & msg)> handler =
+    std::function<void(sdbusplus::message::message&)> handler =
         [callback = std::move(cb)](sdbusplus::message::message msg) {
         sdbusplus::message::object_path objPath;
         msg.read(objPath);
@@ -162,14 +205,41 @@ int main()
         {
             controller->removeObj(objPath.str);
         }
-        // Status
+        // Add Status
         auto statusIfc = objectServer.add_unique_interface(
             objPath, gpiopresencesensing::interfaces::statusIfc);
+        std::cout << "Adding status interface: " << config.name
+                  << " at path: " << objPath.str << std::endl;
         statusIfc->register_property(
             gpiopresencesensing::Properties::propertyPresent, false);
         statusIfc->register_property("Name", config.name);
         statusIfc->initialize();
-        controller->addObj(std::move(statusIfc), objPath.str, config);
+        // Add Inventory Association
+        if (config.generateAssociation)
+        {
+            sdbusplus::message::object_path associationPath(
+                config.associationPath);
+
+            std::cout << "Adding association interface: "
+                      << config.associationPath
+                      << " at path: " << associationPath.str << std::endl;
+
+            auto assocIfc = objectServer.add_unique_interface(
+                associationPath, association::interface);
+            assocIfc->register_property(
+                "Associations",
+                std::vector<Association>{{config.associationForward,
+                                          config.associationReverse,
+                                          config.parentPath}});
+            assocIfc->initialize();
+            controller->addObj(std::move(statusIfc), std::move(assocIfc),
+                               objPath.str, config);
+        }
+        else
+        {
+            controller->addObj(std::move(statusIfc), nullptr, objPath.str,
+                               config);
+        }
         controller->setMinPollRate(config.pollRate);
         // It is possible there are more EM config in the pipeline.
         // Therefore, delay the main loop by 10 seconds to wait for more
--
2.40.1.521.gf1e218fcd8-goog