Add target interface for fan monitor

Current fan monitor assumes the use of the FanSpeed interface for fan
targets.
For fans controlled by pwm, FanPwm interface is added.

This commit adds a "target_interface" config parameter, so that user
can specify the interface for the fan targets.

E.g.

  - name: fan0
    has_target: true
    target_interface: xyz.openbmc_project.Control.FanPwm

This config is optional and defaults to FanSpeed, so the current code
will not be affected.

Tested: Use this config on Romulus, ensures fan monitor gets fan
        target from FanPwm interface and works OK.

Change-Id: I262a486c335b2b43a46af7abdd0e71e95a133b98
Signed-off-by: Lei YU <mine260309@gmail.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/monitor/tach_sensor.hpp b/monitor/tach_sensor.hpp
index 50951cd..2cd0f4a 100644
--- a/monitor/tach_sensor.hpp
+++ b/monitor/tach_sensor.hpp
@@ -62,6 +62,7 @@ class TachSensor
          * @param[in] id - the id of the sensor
          * @param[in] hasTarget - if the sensor supports
          *                        setting the speed
+         * @param[in] interface - the interface of the target
          * @param[in] factor - the factor of the sensor target
          * @param[in] offset - the offset of the sensor target
          * @param[in] timeout - Normal timeout value to use
@@ -72,6 +73,7 @@ class TachSensor
                    Fan& fan,
                    const std::string& id,
                    bool hasTarget,
+                   const std::string& interface,
                    size_t factor,
                    size_t offset,
                    size_t timeout,
@@ -99,6 +101,14 @@ class TachSensor
         }
 
         /**
+         * @brief Returns the interface of the sensor target
+         */
+        inline std::string getInterface() const
+        {
+            return _interface;
+        }
+
+        /**
          * @brief Returns the factor of the sensor target
          */
         inline size_t getFactor() const
@@ -237,6 +247,11 @@ class TachSensor
         const bool _hasTarget;
 
         /**
+         * @brief The interface that the target implements
+         */
+        const std::string _interface;
+
+        /**
          * @brief The factor of target to get fan rpm
          */
         const size_t _factor;