Gitiles
Code Review Sign In
gerrit.openbmc.org / openbmc / phosphor-gpio-monitor / refs/heads/master
commite634209f090fefd02bf5531339b4ecf12517a62f[log] [tgz]
authorPatrick Williams <patrick@stwcx.xyz>Wed Jul 09 11:27:19 2025 -0400
committerPatrick Williams <patrick@stwcx.xyz>Wed Jul 09 11:27:19 2025 -0400
tree126e837851c1edd13ac451f79771cba0829c0b0a
parentba917cf7cf4163f6a71d8f67609237f013149743 [diff]
meson: use non-deprecated systemd packageconfig

Systemd's packageconfig file has both `systemdsystemunitdir` and
`systemd_system_unit_dir` defined.  The non-underscore one appears
to be a deprecated alias[1].  Move to the non-deprecated /
underscore-separated variant.

[1]: https://github.com/systemd/systemd/commit/4908de44b0a0409f84a7cdc5641b114d6ce8ba03

Change-Id: Ia694d45d7f0430519f8593a7968bcd7fe0ebb775
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
1 file changed
tree: 126e837851c1edd13ac451f79771cba0829c0b0a
  1. multi-presence/
  2. presence/
  3. subprojects/
  4. test/
  5. .clang-format
  6. .gitignore
  7. 99-gpio-keys.rules
  8. evdev.cpp
  9. evdev.hpp
  10. file.hpp
  11. gpioMon.cpp
  12. gpioMon.hpp
  13. gpioMonMain.cpp
  14. LICENSE
  15. mainapp.cpp
  16. meson.build
  17. meson.options
  18. monitor.cpp
  19. monitor.hpp
  20. OWNERS
  21. phosphor-gpio-monitor@.service
  22. phosphor-gpio-presence@.service
  23. phosphor-multi-gpio-monitor.json
  24. phosphor-multi-gpio-monitor.service
  25. phosphor-multi-gpio-presence.json
  26. phosphor-multi-gpio-presence.service
  27. README.md
README.md

GPIO Monitoring

Implemented Daemons

phosphor-gpio-monitor

This daemon accepts a command line parameter for monitoring single gpio line and take action if requested. This implementation uses GPIO keys and only supports monitoring single GPIO line, for multiple lines, user has to run this daemon seperately for each gpio line.

phosphor-multi-gpio-monitor

This daemon accepts command line parameter as a well-defined GPIO configuration file in json format to monitor list of gpios from config file and take action defined in config based on gpio state change. It uses libgpiod library.

Difference

New implementation (phosphor-multi-gpio-monitor) provides multiple gpio line monitoring in single instance of phosphor-multi-gpio-monitor running. It is very easy to add list of gpios into JSON config file and it also supports of GPIO line by name defined in kernel.

Configuration

There is a phosphor-multi-gpio-monitor.json file that defines details of GPIOs which is required to be monitored. This file can be replaced with a platform specific configuration file via bbappend.

Following are fields in json file

  1. Name: Name of gpio for reference.
  2. LineName: this is the line name defined in device tree for specific gpio
  3. GpioNum: GPIO offset, this field is optional if LineName is defined.
  4. ChipId: This is device name either offset ("0") or complete gpio device ("gpiochip0"). This field is not required if LineName is defined.
  5. EventMon: Event of gpio to be monitored. This can be "FALLING", "RISING" OR "BOTH". Default value for this is "BOTH".
  6. Target: This is an optional systemd service which will get started after triggering event. A journal entry will be added for every event occurs irrespective of this definition.
  7. Targets: This is an optional systemd service which will get started after triggering corresponding event(RISING or FALLING). A journal entry will be added for every event occurs irrespective of this definition. Upon start up, depending on the current GPIO value, the systemd services for INIT_HIGH and INIT_LOW will be called (if defined).
  8. Continue: This is a optional flag and if it is defined as true then this gpio will be monitored continuously. If not defined then monitoring of this gpio will stop after first event.

Sample config file

[
  {
    "Name": "PowerButton",
    "LineName": "POWER_BUTTON",
    "GpioNum": 34,
    "ChipId": "gpiochip0",
    "EventMon": "FALLING",
    "Target": "PowerButtonDown.service",
    "Continue": true
  },
  {
    "Name": "PowerGood",
    "LineName": "PS_PWROK",
    "EventMon": "BOTH",
    "Targets": {
      "FALLING": ["PowerGoodFalling.service", "PowerOff.service"],
      "RISING": ["PowerGoodRising.service", "PowerOn.service"]
    },
    "Continue": false
  },
  { "Name": "SystemReset", "GpioNum": 46, "ChipId": "0" }
]

phosphor-multi-gpio-presence

This daemon accepts command line parameter as a well-defined GPIO configuration file in json format to monitor list of gpios from config file and sets inventory presence as defined in config based on gpio state change. It uses libgpiod library.

Difference

New implementation (phosphor-multi-gpio-presence) provides multiple gpio line monitoring in single instance of phosphor-multi-gpio-presence running. It is very easy to add list of gpios into JSON config file and it also supports of GPIO line by name defined in kernel.

Configuration

There is a phosphor-multi-gpio-presence.json file that defines details of GPIOs which is required to be monitored. This file can be replaced with a platform specific configuration file via bbappend.

Following are fields in json file

  1. Name: PrettyName of inventory item
  2. LineName: this is the line name defined in device tree for specific gpio
  3. GpioNum: GPIO offset, this field is optional if LineName is defined.
  4. ChipId: This is device name either offset ("0") or complete gpio device ("gpiochip0"). This field is not required if LineName is defined.
  5. Inventory: Object path under inventory that will be created
  6. ExtraInterfaces: [Optional] List of interfaces to associate to inventory item
  7. ActiveLow: [Optional] Object is present on LOW level
  8. Bias: [Optional] Configure a BIAS on the GPIO line, for example PULL_UP

Sample config file

[
  {
    "Name": "DIMM A0",
    "LineName": "POWER_BUTTON",
    "Inventory": "/system/chassis/motherboard/dimm_a0"
  },
  {
    "Name": "Powersupply 0",
    "ChipId": "0",
    "GpioNum": 14,
    "Inventory": "/system/chassis/motherboard/powersupply0",
    "ActiveLow": true,
    "Bias": "PULL_UP",
    "ExtraInterfaces": ["xyz.openbmc_project.Inventory.Item.PowerSupply"]
  }
]