test(dbus): Add support for testing driver reset notification

Introduce `FakeResetDriverWatchdog` to simulate driver reset triggers.
Update existing tests and add a new test, `test_notify_reset_driver`, to
verify reset notifications using the event signaling mechanism.

debian/changelog

@@ -1,27 +0,0 @@
-revpi-middleware (0.0.1-1+deb12+1) bookworm; urgency=medium
-
-  * docs: Start git project with python git-ignore and Readme
-  * docs: Use 'reuse' for SPDX Headers and Licenses
-  * feat: Add python base project files
-  * feat: Add proginit application basic module
-  * feat: Add the data directory for additional data files for the project
-  * test: Add tests directory with a dummy test
-  * build: Add all necessary files for the build system
-  * feat: Add dummy main application script
-  * feat: Add systemd file and data to integrate the app as a daemon
-  * chore: Update proginit to 1.4.0
-  * feat(dbus): Add ResetDriverWatchdog helper as global dbus helper
-  * feat(process_image): Add D-Bus interface for piControl driver
-  * feat(dbus): Add initial D-Bus middleware implementation
-  * feat(dbus): Add `extend_interface` function for dynamic interface naming
-  * feat(dbus): Add DBus policy configuration for revpi-middleware
-  * feat: Add MiddlewareDaemon implementation to revpi-middleware
-  * feat: Add daemon mode and signal handling to main application
-  * feat(cli): Add D-Bus helper functions for CLI commands.
-  * feat(cli): Add await_signal function to handle D-Bus signals
-  * feat(cli): Add `await-reset` to wait for piControl reset signal
-  * chore(build): Update requirements for this project
-  * feat(cli): Add new CLI tool entry point for `revpictl`
-  * feat(deb): Start packaging branch
-
- -- Sven Sager <s.sager@kunbus.com>  Fri, 18 Apr 2025 19:02:20 +0200

debian/control

@@ -1,36 +0,0 @@
-Source: revpi-middleware
-Section: python
-Priority: optional
-Maintainer: KUNBUS GmbH <support@kunbus.com>
-Rules-Requires-Root: no
-Homepage: https://revolutionpi.com/
-Vcs-Browser: https://gitlab.com/revolutionpi/revpi-middleware
-Vcs-Git: https://gitlab.com/revolutionpi/revpi-middleware.git -b debian/bookworm
-Build-Depends:
-  debhelper-compat (= 13),
-  dh-python,
-  python3-all,
-  python3-gi (>= 3.42.2),
-  python3-pydbus (>= 0.6.0),
-  python3-setuptools,
-Standards-Version: 4.6.2
-
-Package: revpi-middleware
-Architecture: all
-Pre-Depends: ${misc:Pre-Depends}
-Depends:
-  ${python3:Depends},
-  ${misc:Depends}
-Description: Revolution Pi middleware with D-Bus interface
- The Revolution Pi middleware provides a robust communication interface for
- Revolution Pi industrial computers. It enables seamless integration between
- hardware components and applications through a D-Bus interface. The middleware
- serves as a bridge for data exchange, device configuration, and system
- monitoring.
- .
- Key features:
-  * Hardware abstraction layer for Revolution Pi I/O modules
-  * Real-time data processing and event handling
-  * Simplified API for accessing Revolution Pi hardware features
-  * Extensive configuration options for industrial automation tasks
-  * Built-in monitoring and diagnostic capabilities

debian/copyright

@@ -1,27 +0,0 @@
-Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
-Source: https://gitlab.com/revolutionpi/opcua-revpi-server
-
-Files: *
-Copyright: 2025 KUNBUS GmbH
-License: GPL-2+
-
-Files: debian/*
-Copyright: 2025 KUNBUS GmbH
-License: GPL-2+
-
-License: GPL-2+
- This package is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
- .
- This package is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- GNU General Public License for more details.
- .
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <https://www.gnu.org/licenses/>
- .
- On Debian systems, the complete text of the GNU General
- Public License version 2 can be found in "/usr/share/common-licenses/GPL-2".

debian/gbp.conf

@@ -1,7 +0,0 @@
-[DEFAULT]
-upstream-branch = main
-upstream-tag = v%(version)s
-debian-branch=debian/bookworm
-debian-tag = debian/%(version)s
-debian-tag-msg = %(pkg)s Debian release %(version)s
-pristine-tar = True

debian/revpi-middleware.install

@@ -1,4 +0,0 @@
-data/dbus-policy/com.revolutionpi.middleware1.conf      /usr/share/dbus-1/system.d
-data/etc/default/revpi-middleware                       /etc/default/
-data/etc/revpi-middleware/revpi-middleware.conf         /etc/revpi-middleware/
-data/systemd/before_253/revpi-middleware.service        /lib/systemd/system/

debian/revpi-middleware.links

@@ -1,2 +0,0 @@
-/usr/share/revpi-middleware/revpi-middleware	/usr/sbin/revpi-middleware
-/usr/share/revpi-middleware/revpicli	/usr/bin/revpicli

debian/rules

@@ -1,7 +0,0 @@
-#!/usr/bin/make -f
-
-export PYBUILD_NAME=revpi-middleware
-export PYBUILD_INSTALL_ARGS=--install-lib=/usr/share/$(PYBUILD_NAME)/ --install-scripts=/usr/share/$(PYBUILD_NAME)/
-
-%:
-	dh $@ --with python3 --buildsystem=pybuild

debian/source/format

@@ -1 +0,0 @@
-3.0 (quilt)

src/revpi_middleware/cli_commands/cli_picontrol.py

@@ -4,7 +4,7 @@
 from argparse import ArgumentParser
 from logging import getLogger
 
-from .dbus_helper import await_signal, simple_call
+from .dbus_helper import BusType, await_signal, simple_call
 from .. import proginit as pi
 from ..dbus_middleware1 import extend_interface
 
@@ -36,12 +36,21 @@ def add_subparsers(parent_parser: ArgumentParser):
 
 def method_reset():
     log.debug("D-Bus call of method ResetDriver")
-    simple_call("ResetDriver", interface=extend_interface("picontrol"))
+    simple_call(
+        "ResetDriver",
+        interface=extend_interface("picontrol"),
+        bus_type=BusType.SESSION if pi.pargs.use_session_bus else BusType.SYSTEM,
+    )
     log.info("ResetDriver called via D-Bus")
 
 
-def method_await_reset(timout: int = 0):
-    detected_signal = await_signal("NotifyDriverReset", timout, extend_interface("picontrol"))
+def method_await_reset(timeout: int = 0):
+    detected_signal = await_signal(
+        "NotifyDriverReset",
+        timeout,
+        extend_interface("picontrol"),
+        bus_type=BusType.SESSION if pi.pargs.use_session_bus else BusType.SYSTEM,
+    )
     if detected_signal:
         log.info("ResetDriver signal received")
     else:

src/revpi_middleware/cli_commands/dbus_helper.py

@@ -1,50 +1,101 @@
 # SPDX-FileCopyrightText: 2025 KUNBUS GmbH
 # SPDX-License-Identifier: GPL-2.0-or-later
 """D-Bus helper functions for cli commands."""
+from enum import Enum
 from threading import Thread
 from time import sleep
 
 from gi.repository import GLib
-from pydbus import SystemBus
+from pydbus import SessionBus, SystemBus
 
 from ..dbus_middleware1 import REVPI_DBUS_BASE_PATH
 from ..dbus_middleware1 import REVPI_DBUS_NAME
 
-PICONTROL_INTERFACE = "com.revolutionpi.middleware1.picontrol"
-RESET_DRIVER_METHOD = "ResetDriver"
+
+class BusType(Enum):
+    SESSION = "session"
+    SYSTEM = "system"
 
 
-def simple_call(method: str, *args, interface: str, object_path=REVPI_DBUS_BASE_PATH):
+def simple_call(
+    method: str,
+    *args,
+    interface: str,
+    object_path=REVPI_DBUS_BASE_PATH,
+    bus_type=BusType.SYSTEM,
+):
     """
-    Executes a method on a specific D-Bus object interface within the RevPi system. This function
-    connects to the system bus, retrieves the desired interface and object path, and invokes
-    the specified method with provided arguments.
+    Performs a call to a D-Bus method on a specified interface and object.
+
+    This function uses the D-Bus messaging system to dynamically call a method
+    of a specified interface, using the given object path and bus type. It
+    provides a way to interact with D-Bus interfaces, using either a system or
+    session bus, and returns the result of executing the specified method.
 
     Parameters:
     method: str
-        The name of the method to be invoked on the targeted interface.
-    *args: tuple
-        Positional arguments to be passed to the method being invoked.
+        The name of the method to invoke on the D-Bus interface.
+    *args:
+        Additional positional arguments to pass to the specified D-Bus method.
     interface: str
-        The name of the D-Bus interface providing the required functionality.
-    object_path: str, optional
-        The D-Bus object path of the RevPi interface. Defaults to REVPI_DBUS_BASE_PATH.
+        The name of the D-Bus interface containing the method.
+    object_path:
+        The path of the D-Bus object on which the interface is defined. Defaults
+        to REVPI_DBUS_BASE_PATH.
+    bus_type: BusType
+        Specifies whether to use the system or session bus. Defaults to BusType.SYSTEM.
 
     Returns:
-    Any
-        The result of the method invocation on the targeted D-Bus interface.
+        The value returned by the D-Bus method.
+
+    Raises:
+        Any errors raised from the D-Bus call will propagate to the caller.
     """
-    bus = SystemBus()
+    bus = SessionBus() if bus_type is BusType.SESSION else SystemBus()
     revpi = bus.get(REVPI_DBUS_NAME, object_path)
     iface = revpi[interface]
     return getattr(iface, method)(*args)
 
 
-def await_signal(signal_name: str, timeout: int, interface: str, object_path=REVPI_DBUS_BASE_PATH):
+def await_signal(
+    signal_name: str,
+    timeout: int,
+    interface: str,
+    object_path=REVPI_DBUS_BASE_PATH,
+    bus_type=BusType.SYSTEM,
+):
+    """
+    Waits for a specific signal and returns whether the signal was detected.
+
+    This function connects to a D-Bus interface and waits for a specific signal
+    to be emitted. If the signal is not received within the specified timeout
+    period, the function will return False. If the signal is detected within
+    the timeout, the function will return True. It can connect to either the
+    system bus or the session bus, depending on the provided `bus_type`.
+
+    Parameters:
+    signal_name: str
+        The name of the signal to be awaited.
+    timeout: int
+        The maximum time to wait for the signal, in seconds. A value of 0 or
+        less means that there is no timeout.
+    interface: str
+        The name of the D-Bus interface to listen on.
+    object_path
+        The D-Bus object path where the interface resides. Defaults to
+        REVPI_DBUS_BASE_PATH.
+    bus_type
+        The type of D-Bus to connect to. Can be either BusType.SYSTEM or
+        BusType.SESSION. Defaults to BusType.SYSTEM.
+
+    Returns:
+    bool
+        True if the signal was detected within the timeout period, False
+        otherwise.
+    """
     detected_signal = False
     timeout = int(timeout)
     loop = GLib.MainLoop()
-    th_sleep = Thread()
 
     def th_timeout():
         sleep(timeout)
@@ -55,7 +106,7 @@ def await_signal(signal_name: str, timeout: int, interface: str, object_path=REV
         detected_signal = True
         loop.quit()
 
-    bus = SystemBus()
+    bus = SessionBus() if bus_type is BusType.SESSION else SystemBus()
     revpi = bus.get(REVPI_DBUS_NAME, object_path)
     iface = revpi[interface]
 

src/revpi_middleware/daemon.py

@@ -42,7 +42,7 @@ class MiddlewareDaemon:
         if self.bus_provider and self.bus_provider.is_alive():
             return
 
-        self.bus_provider = BusProvider()
+        self.bus_provider = BusProvider(use_system_bus=not pi.pargs.use_session_bus)
         self.bus_provider.start()
 
         log.debug("leave MiddlewareDaemon.dbus_start")

src/revpi_middleware/dbus_middleware1/__init__.py

@@ -2,27 +2,7 @@
 # SPDX-FileCopyrightText: 2025 KUNBUS GmbH
 # SPDX-License-Identifier: GPL-2.0-or-later
 """D-Bus middleware version 1 of revpi_middleware."""
-from ..__about__ import __author__, __copyright__, __license__, __version__
+from .dbus_helper import REVPI_DBUS_BASE_PATH, REVPI_DBUS_NAME
+from .dbus_helper import extend_interface
 
-REVPI_DBUS_NAME = "com.revolutionpi.middleware1"
-REVPI_DBUS_BASE_PATH = "/com/revolutionpi/middleware1"
-
-
-def extend_interface(*args) -> str:
-    """
-    Extends an interface name by appending additional segments to a pre-defined base name.
-
-    This function takes multiple arguments, concatenates them with a predefined base
-    interface name, and returns the resulting string, effectively constructing an
-    extended interface name.
-
-    Args:
-        *args: str
-            Components to be appended to the base interface name.
-
-    Returns:
-        str
-            Fully constructed interface name by joining the base interface name with
-            the provided segments.
-    """
-    return ".".join([REVPI_DBUS_NAME, *args])
+from .bus_provider import BusProvider

src/revpi_middleware/dbus_middleware1/bus_provider.py

@@ -6,7 +6,7 @@ from logging import getLogger
 from threading import Thread
 
 from gi.repository import GLib
-from pydbus import SystemBus
+from pydbus import SessionBus, SystemBus
 
 from . import REVPI_DBUS_NAME
 from .process_image import InterfacePiControl
@@ -16,25 +16,59 @@ log = getLogger(__name__)
 
 class BusProvider(Thread):
 
-    def __init__(self):
+    def __init__(
+        self,
+        picontrol_device="/dev/piControl0",
+        config_rsc="/etc/revpi/config.rsc",
+        use_system_bus=True,
+    ):
         log.debug("enter BusProvider.__init__")
         super().__init__()
 
-        self._bus = SystemBus()
+        self._bus = SystemBus() if use_system_bus else SessionBus()
         self._loop = GLib.MainLoop()
 
+        self.picontrol_device = picontrol_device
+        self.config_rsc = config_rsc
+
     def run(self):
         log.debug("enter BusProvider.run")
 
-        self._bus.publish(
-            REVPI_DBUS_NAME,
-            InterfacePiControl(),
-        )
+        # The 2nd, 3rd, ... arguments can be objects or tuples of a path and an object
+        #   Example(),
+        #   ("Subdir1", Example()),
+        #   ("Subdir2", Example()),
+        #   ("Subdir2/Whatever", Example())
+        lst_interfaces = [
+            InterfacePiControl(self.picontrol_device, self.config_rsc),
+        ]
+
+        try:
+            self._bus.publish(
+                REVPI_DBUS_NAME,
+                *lst_interfaces,
+            )
+        except Exception as e:
+            log.error(f"can not publish dbus {REVPI_DBUS_NAME}: {e}")
+
+        try:
+            self._loop.run()
+        except Exception as e:
+            log.error(f"can not run dbus mainloop: {e}")
+
+        # Clean up all interfaces
+        for interface in lst_interfaces:
+            if type(interface) is tuple:
+                _, interface = interface
+            interface.cleanup()
 
-        self._loop.run()
         log.debug("leave BusProvider.run")
 
     def stop(self):
         log.debug("enter BusProvider.stop")
         self._loop.quit()
         log.debug("leave BusProvider.stop")
+
+    @property
+    def running(self):
+        return self._loop.is_running()

src/revpi_middleware/dbus_middleware1/dbus_helper.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+"""Helper for dbus."""
+
+from logging import getLogger
+
+log = getLogger(__name__)
+
+REVPI_DBUS_NAME = "com.revolutionpi.middleware1"
+REVPI_DBUS_BASE_PATH = "/com/revolutionpi/middleware1"
+
+
+class DbusInterface:
+
+    def cleanup(self):
+        """
+        Represents a method responsible for performing cleanup operations. This method is executed to properly
+        release resources, close connections, or perform other necessary finalization tasks.
+
+        This method does not take any arguments or return a value.
+        """
+        pass
+
+
+def extend_interface(*args) -> str:
+    """
+    Extends an interface name by appending additional segments to a pre-defined base name.
+
+    This function takes multiple arguments, concatenates them with a predefined base
+    interface name, and returns the resulting string, effectively constructing an
+    extended interface name.
+
+    Args:
+        *args: str
+            Components to be appended to the base interface name.
+
+    Returns:
+        str
+            Fully constructed interface name by joining the base interface name with
+            the provided segments.
+    """
+    return ".".join([REVPI_DBUS_NAME, *args])

src/revpi_middleware/dbus_middleware1/process_image/interface_picontrol.py

@@ -2,18 +2,17 @@
 # SPDX-FileCopyrightText: 2025 KUNBUS GmbH
 # SPDX-License-Identifier: GPL-2.0-or-later
 """D-Bus interfaces for piControl."""
-import os
-from fcntl import ioctl
 from logging import getLogger
 
 from pydbus.generic import signal
 
-from ..interface_helper import ResetDriverWatchdog
+from .process_image_helper import PiControlIoctl, ResetDriverWatchdog
+from ..dbus_helper import DbusInterface
 
 log = getLogger(__name__)
 
 
-class InterfacePiControl:
+class InterfacePiControl(DbusInterface):
     """
     <node>
         <interface name='com.revolutionpi.middleware1.picontrol'>
@@ -27,12 +26,16 @@ class InterfacePiControl:
 
     NotifyDriverReset = signal()
 
-    def __init__(self):
-        self.pi_control = "/dev/piControl0"
+    def __init__(self, picontrol_device: str, config_rsc: str):
+        self.picontrol_device = picontrol_device
+        self.config_rsc = config_rsc
 
-        self.wd_reset_driver = ResetDriverWatchdog(self.pi_control)
+        self.wd_reset_driver = ResetDriverWatchdog(self.picontrol_device)
         self.wd_reset_driver.register_call(self.notify_reset_driver)
 
+    def cleanup(self):
+        self.wd_reset_driver.stop()
+
     def notify_reset_driver(self):
         self.NotifyDriverReset()
 
@@ -40,21 +43,9 @@ class InterfacePiControl:
         log.debug("enter InterfacePiControl.ResetDriver")
 
         try:
-            fd = os.open(self.pi_control, os.O_WRONLY)
-        except Exception as e:
-            log.warning(f"could not open ${self.pi_control} to reset driver")
-            raise e
-
-        execption = None
-        try:
-            # KB_RESET _IO('K', 12 )  // reset the piControl driver including the config file
-            ioctl(fd, 19212)
+            picontrol_ioctl = PiControlIoctl(self.picontrol_device)
+            picontrol_ioctl.ioctl(PiControlIoctl.IOCTL_RESET_DRIVER)
             log.info("reset piControl driver")
         except Exception as e:
             log.warning(f"could not reset piControl driver: ${e}")
-            execption = e
-        finally:
-            os.close(fd)
-
-        if execption:
-            raise execption
+            raise e

src/revpi_middleware/dbus_middleware1/process_image/process_image_helper.py

@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-# SPDX-FileCopyrightText: 2020-2023 Sven Sager
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
 # SPDX-License-Identifier: GPL-2.0-or-later
 """
 Helper for the process image.
@@ -7,8 +7,8 @@ Helper for the process image.
 The ResetDriverWatchdog class is a copy of revpipyload project module "watchdogs"
 https://github.com/naruxde/revpipyload/blob/b51c2b617a57cc7d96fd67e1da9f090a0624eacb/src/revpipyload/watchdogs.py
 """
-
 import os
+from ctypes import c_int
 from fcntl import ioctl
 from logging import getLogger
 from threading import Thread
@@ -19,9 +19,9 @@ log = getLogger(__name__)
 class ResetDriverWatchdog(Thread):
     """Watchdog to catch the reset_driver action."""
 
-    def __init__(self, pi_control_device="/dev/piControl0"):
+    def __init__(self, picontrol_device: str):
         super(ResetDriverWatchdog, self).__init__()
-        self.procimg = pi_control_device
+        self.procimg = picontrol_device
         self.daemon = True
         self._calls = []
         self._exit = False
@@ -35,7 +35,7 @@ class ResetDriverWatchdog(Thread):
         """
         Mainloop of watchdog for reset_driver.
 
-        If the thread can not open the process image or the IOCTL is not
+        If the thread cannot open the process image or the IOCTL is not
         implemented (wheezy), the thread function will stop. The trigger
         property will always return True.
         """
@@ -51,7 +51,7 @@ class ResetDriverWatchdog(Thread):
             )
             return
 
-        # The ioctl will return 2 byte (c-type int)
+        # The ioctl will return 2 bytes (c-type int)
         byte_buff = bytearray(2)
         while not self._exit:
             try:
@@ -73,7 +73,7 @@ class ResetDriverWatchdog(Thread):
     def register_call(self, function):
         """Register a function, if watchdog triggers."""
         if not callable(function):
-            return ValueError("Function is not callable.")
+            raise ValueError("Function is not callable.")
         if function not in self._calls:
             self._calls.append(function)
 
@@ -89,7 +89,7 @@ class ResetDriverWatchdog(Thread):
         log.debug("leave ResetDriverWatchdog.stop()")
 
     def unregister_call(self, function=None):
-        """Remove a function call on watchdog trigger."""
+        """Remove a function from the watchdog trigger."""
         if function is None:
             self._calls.clear()
         elif function in self._calls:
@@ -101,3 +101,24 @@ class ResetDriverWatchdog(Thread):
         rc = self._triggered
         self._triggered = False
         return rc
+
+
+class PiControlIoctl:
+    IOCTL_RESET_DRIVER = 19212
+
+    def __init__(self, picontrol_device: str):
+        self.picontrol_device = picontrol_device
+
+    def ioctl(self, request, arg=0):
+        if type(arg) is c_int:
+            arg = arg.value
+
+        _fd = os.open(self.picontrol_device, os.O_WRONLY)
+        return_value = ioctl(_fd, 19212, arg)
+        os.close(_fd)
+
+        return return_value
+
+    @property
+    def name(self):
+        return self.picontrol_device

src/revpi_middleware/proginit.py

@@ -9,7 +9,7 @@ __version__ = "1.4.0"
 
 import logging
 import sys
-from argparse import ArgumentParser, Namespace
+from argparse import ArgumentParser, Namespace, SUPPRESS
 from configparser import ConfigParser
 from enum import Enum
 from os import R_OK, W_OK, access, environ, getpid, remove
@@ -262,6 +262,16 @@ parser = ArgumentParser(
     prog=programname,
     description="Program description",
 )
+
+# Use session bus of D-Bus for local testing and development proposes (hidden)
+parser.add_argument(
+    "--use-session-bus",
+    dest="use_session_bus",
+    action="store_true",
+    default=False,
+    help=SUPPRESS,
+)
+
 parser.add_argument("--version", action="version", version=f"%(prog)s {program_version}")
 parser.add_argument(
     "-f",

tests/__init__.py

@@ -0,0 +1,3 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later

tests/dbus_middleware1/__init__.py

@@ -0,0 +1,7 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+from os import environ
+
+# D-BUS needs a DISPLAY variable to work with the session bus
+environ["DISPLAY"] = ":0"

tests/dbus_middleware1/bus_provider.py

@@ -0,0 +1,36 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+from time import sleep
+
+from tests.dbus_middleware1.fake_devices import PiControlDeviceMockup
+
+
+class TestBusProvider(PiControlDeviceMockup):
+
+    def setUp(self):
+        super().setUp()
+
+        # Do not import things on top of the module. Some classes or functions need to be mocked up first.
+        from revpi_middleware.dbus_middleware1 import BusProvider
+
+        # Prepare the bus provider and start it
+        self.bp = BusProvider(
+            self.picontrol.name,
+            use_system_bus=False,
+        )
+        self.bp.start()
+
+        # Wait 5 seconds until the bus provider has started the main loop
+        counter = 50
+        while not self.bp.running and counter > 0:
+            counter -= 1
+            sleep(0.1)
+
+    def tearDown(self):
+        self.bp.stop()
+        self.bp.join(10.0)
+        if self.bp.is_alive():
+            raise RuntimeError("Bus provider thread is still running")
+
+        super().tearDown()

tests/dbus_middleware1/fake_devices.py

@@ -0,0 +1,120 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+from ctypes import c_int
+from queue import Empty, Queue
+from tempfile import NamedTemporaryFile
+from threading import Event, Thread
+from unittest import TestCase
+
+IOCTL_QUEUE = Queue()
+RESET_DRIVER_EVENT = Event()
+
+
+class FakePiControlDevice:
+    IOCTL_RESET_DRIVER = 19212
+
+    def __init__(self, picontrol_device: str):
+        self._fh = NamedTemporaryFile("wb+", 0, prefix="fake_device_")
+        self.name = self._fh.name
+
+    def __del__(self):
+        self._fh.close()
+
+    def reset_process_image(self):
+        self._fh.write(b"\x00" * 4096)
+        self._fh.seek(0)
+
+    def ioctl(self, request, arg=0) -> int:
+        if type(arg) is c_int:
+            arg = arg.value
+
+        if request == self.IOCTL_RESET_DRIVER:
+            pass
+        else:
+            raise NotImplementedError(f"Unknown IOCTL request: {request}")
+
+        IOCTL_QUEUE.put_nowait((request, arg))
+        return arg
+
+    def close(self):
+        self._fh.close()
+
+    def read(self, size):
+        return self._fh.read(size)
+
+    def seek(self, offset, whence):
+        self._fh.seek(offset, whence)
+
+    def write(self, buffer):
+        return self._fh.write(buffer)
+
+
+class FakeResetDriverWatchdog(Thread):
+
+    def __init__(self, picontrol_device: str):
+        super().__init__()
+        self.daemon = True
+        self._calls = []
+        self._exit = False
+        self.not_implemented = True
+        self._triggered = False
+        self.start()
+
+    def run(self):
+        while not self._exit:
+            if RESET_DRIVER_EVENT.wait(0.1):
+                RESET_DRIVER_EVENT.clear()
+                self._triggered = True
+                for func in self._calls:
+                    func()
+
+    def register_call(self, function):
+        """Register a function, if watchdog triggers."""
+        if not callable(function):
+            raise ValueError("Function is not callable.")
+        if function not in self._calls:
+            self._calls.append(function)
+
+    def stop(self):
+        """Stop watchdog for reset_driver."""
+        self._exit = True
+
+    def unregister_call(self, function=None):
+        """Remove a function from the watchdog trigger."""
+        if function is None:
+            self._calls.clear()
+        elif function in self._calls:
+            self._calls.remove(function)
+
+    @property
+    def triggered(self):
+        """Will return True one time after watchdog was triggered."""
+        rc = self._triggered
+        self._triggered = False
+        return rc
+
+
+class PiControlDeviceMockup(TestCase):
+
+    def setUp(self):
+        super().setUp()
+
+        # Empty the queue
+        while True:
+            try:
+                IOCTL_QUEUE.get_nowait()
+            except Empty:
+                break
+
+        # Replace classes with mockup classes
+        import revpi_middleware.dbus_middleware1.process_image.interface_picontrol as test_helpers
+        test_helpers.PiControlIoctl = FakePiControlDevice
+        test_helpers.ResetDriverWatchdog = FakeResetDriverWatchdog
+
+        # Create a fake picontrol0 device
+        self.picontrol = FakePiControlDevice(picontrol_device="/dev/fake_device_0")
+
+    def tearDown(self):
+        self.picontrol.close()
+        super().tearDown()

tests/dbus_middleware1/process_image/__init__.py

@@ -0,0 +1,3 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later

tests/dbus_middleware1/process_image/test_interface_picontrol.py

@@ -0,0 +1,45 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+from threading import Thread
+from time import sleep
+
+from revpi_middleware.cli_commands.dbus_helper import BusType, await_signal, simple_call
+from revpi_middleware.dbus_middleware1 import extend_interface
+from tests.dbus_middleware1.bus_provider import TestBusProvider
+from tests.dbus_middleware1.fake_devices import IOCTL_QUEUE, RESET_DRIVER_EVENT
+
+
+class TestObjectPicontrol(TestBusProvider):
+
+    def test_is_active(self):
+        self.assertTrue(self.bp.running)
+
+    def test_reset_driver(self):
+        simple_call(
+            "ResetDriver",
+            interface=extend_interface("picontrol"),
+            bus_type=BusType.SESSION,
+        )
+        ioctl_call = IOCTL_QUEUE.get(timeout=2.0)
+        self.assertEqual((19212, 0), ioctl_call)
+
+    def test_notify_reset_driver(self):
+        timeout = 5
+
+        def target_call_reset_driver():
+            sleep(1.0)
+            RESET_DRIVER_EVENT.set()
+
+        th_wait_for_reset = Thread(target=target_call_reset_driver, daemon=True)
+        th_wait_for_reset.start()
+
+        result = await_signal(
+            "NotifyDriverReset",
+            timeout,
+            extend_interface("picontrol"),
+            bus_type=BusType.SESSION,
+        )
+        self.assertTrue(result)
+
+        th_wait_for_reset.join(timeout=timeout)