docs/presence/README.md

5 - [Overview](#overview)
6 - [Data Format](#data-format)
7 - [Example](#example)
8 - [System Config Location](#system-config-location)
9 - [Contents](#contents)
10 - [Validation](#validation)
11 - [Firmware Updates](#firmware-updates)
12 - [Loading and Reloading](#loading-and-reloading)
16 The `phosphor-fan-presence-tach` application is controlled by a configuration
32 ## System Config Location
38 `/usr/share/phosphor-fan-presence/presence/`
40 The supported version of the config file is installed under this read-only
41 directory location as part of the firmware image install. This is where the
46 Where a single config file for 1-or-more system types can be used, the config
49 i.e.) `/usr/share/phosphor-fan-presence/presence/config.json`
51 #### Compatible System Type Location
53 The config file location can also be based on a system type. This is necessary
54 where more than one type of machine is supported in a single BMC firmware image
55 and those system types can not share a common config file.
57 A system type sub-directory can be obtained from the
58 `Inventory.Decorator.Compatible` D-Bus interface's `Names` property. The
59 property holds a list of one or more compatible system types.
63 - `com.ampere.Hardware.Chassis.Model.MtJade`
64 - `com.ampere.Hardware.Chassis.Model.MtMitchell`
66 The `phosphor-fan-presence-tach` application then traverses the supported
67 directory, appending each compatible system type entry as a sub-directory on
72 1. `/usr/share/phosphor-fan-presence/presence/com.ampere.Hardware.Chassis.Model.MtJade/`
73    - (directory/config file does not exist)
74 2. `/usr/share/phosphor-fan-presence/presence/com.ampere.Hardware.Chassis.Model.MtMitchell/config.j…
75    - (config file found)
78 and `phosphor-fan-presence-tach` application terminates preventing the machine
83 `/etc/phosphor-fan-presence/presence/`
87 firmware image on the BMC when changing the configuration, such as for testing
93 `mkdir -p /etc/phosphor-fan-presence/presence`
97 The `phosphor-fan-presence-tach` application will search for the config file at
102    - Default location
103    - Compatible System Type location
117     "path": "/system/chassis/motherboard/fan0",
140 - [name](name.md)
141 - [path](path.md)
142 - [methods](methods.md)
143 - [rpolicy](rpolicy.md)
144 - [eeprom](eeprom.md) _optional_
163       "First fan in the system",
167     "path": "/system/chassis/motherboard/fan0",
198 ## Firmware Updates
200 When a new firmware image is installed on the BMC, it will update the config
203 The override directory will **not** be modified by a firmware update. If a
210 The config file is loaded when the `phosphor-fan-presence-tach` application
216 `systemctl kill -s HUP phosphor-fan-presence-tach@0.service`
220 `journalctl -u phosphor-fan-presence-tach@0.service | grep Loading`