feat(dbus): Add InterfaceWlan for WLAN configuration management

Introduced `InterfaceWlan` to enable/disable WLAN hardware, check
availability, and track status via D-Bus. Integrated the new interface
with the bus provider initialization to ensure proper registration.

Signed-off-by: Sven Sager <s.sager@kunbus.com>

src/revpi_middleware/dbus_middleware1/bus_provider.py

@@ -10,7 +10,7 @@ from pydbus import SessionBus, SystemBus
 
 from . import REVPI_DBUS_NAME
 from .process_image import InterfacePiControl
-from .system_config import InterfaceRevpiConfig, InterfaceSoftwareServices
+from .system_config import InterfaceRevpiConfig, InterfaceSoftwareServices, InterfaceWlan
 
 log = getLogger(__name__)
 
@@ -44,6 +44,7 @@ class BusProvider(Thread):
             InterfacePiControl(self._bus, self.picontrol_device, self.config_rsc),
             InterfaceRevpiConfig(self._bus),
             InterfaceSoftwareServices(self._bus),
+            InterfaceWlan(self._bus),
         ]
 
         try:

src/revpi_middleware/dbus_middleware1/system_config/__init__.py

@@ -4,3 +4,4 @@
 """D-Bus interfaces for system configuration."""
 from .interface_config import InterfaceRevpiConfig
 from .interface_services import InterfaceSoftwareServices
+from .interface_wlan import InterfaceWlan

src/revpi_middleware/dbus_middleware1/system_config/interface_config.py

@@ -14,7 +14,6 @@ from .revpi_config import (
     configure_dphys_swapfile,
     configure_external_antenna,
     configure_gui,
-    configure_wlan,
 )
 from ..dbus_helper import DbusInterface
 
@@ -98,6 +97,5 @@ AVAILABLE_FEATURES = {
     "revpi-con-can": FeatureFunction(configure_con_can, []),
     "swapfile": FeatureFunction(configure_dphys_swapfile, []),
     "bluetooth": FeatureFunction(configure_bluetooth, []),
-    "wlan": FeatureFunction(configure_wlan, []),
     "external-antenna": FeatureFunction(configure_external_antenna, []),
 }

src/revpi_middleware/dbus_middleware1/system_config/interface_wlan.py

@@ -0,0 +1,90 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+"""D-Bus interfaces for wlan configuration."""
+from logging import getLogger
+from threading import Event, Thread
+
+from pydbus.generic import signal
+
+from .revpi_config import configure_wlan, ConfigActions
+from ..dbus_helper import DbusInterface
+
+log = getLogger(__name__)
+
+
+class InterfaceWlan(DbusInterface):
+    """
+    <node>
+        <interface name="com.revolutionpi.middleware1.WlanConfiguration">
+            <method name="Enable">
+                <annotation name="org.freedesktop.DBus.Method.NoReply" value="true"/>
+            </method>
+            <method name="Disable">
+                <annotation name="org.freedesktop.DBus.Method.NoReply" value="true"/>
+            </method>
+            <property name="available" type="b" access="read">
+                <annotation name="org.freedesktop.DBus.Property.EmitsChangedSignal" value="const"/>
+            </property>
+            <property name="status" type="s" access="read">
+                <annotation name="org.freedesktop.DBus.Property.EmitsChangedSignal" value="true"/>
+            </property>
+        </interface>
+    </node>
+    """
+
+    PropertiesChanged = signal()
+
+    def __init__(self, bus):
+        super().__init__(bus)
+        self._status = ""
+
+        # NetworkManager-Objekt abrufen
+        self.bus_nm = self.bus.get(
+            "org.freedesktop.NetworkManager",
+            "/org/freedesktop/NetworkManager",
+        )
+
+        # Prepare status value and thread
+        self.evt_stop_threading = Event()
+        self._update_status(suppress_signal=True)
+        self.th_run_status_update = Thread(
+            target=self._run_status_update,
+            daemon=True,
+        ).start()
+
+    def _run_status_update(self, *args, **kwargs):
+        while not self.evt_stop_threading.wait(1.0):
+            self._update_status()
+
+    def _update_status(self, suppress_signal=False) -> None:
+        str_status = "enabled" if configure_wlan(ConfigActions.STATUS) else "disabled"
+        if self._status != str_status:
+            self._status = str_status
+
+            if not suppress_signal:
+                self.PropertiesChanged(
+                    "com.revolutionpi.middleware1.WlanConfiguration",
+                    {"status": str_status},
+                    [],
+                )
+
+    def cleanup(self):
+        self.evt_stop_threading.set()
+
+    def Disable(self) -> None:
+        """Disable integrated WLAN hardware."""
+        configure_wlan(ConfigActions.DISABLE)
+
+    def Enable(self) -> None:
+        """Enable integrated WLAN hardware."""
+        configure_wlan(ConfigActions.ENABLE)
+
+    @property
+    def available(self) -> bool:
+        """Check if WLAN hardware is available."""
+        return configure_wlan(ConfigActions.AVAILABLE)
+
+    @property
+    def status(self) -> str:
+        return self._status

src/revpi_middleware/dbus_middleware1/system_config/revpi_config.py

@@ -25,6 +25,7 @@ ConfigVariable = namedtuple("ConfigVariable", ["name", "value", "line_index"])
 LINUX_BT_CLASS_PATH = "/sys/class/bluetooth"
 LINUX_WLAN_CLASS_PATH = "/sys/class/ieee80211"
 CONFIG_TXT_LOCATIONS = ("/boot/firmware/config.txt", "/boot/config.txt")
+CMDLINE_TXT_LOCK = Lock()
 CONFIG_TXT_LOCK = Lock()
 
 
@@ -221,6 +222,87 @@ class RevPiConfig:
         return bool(self._wlan_class_path)
 
 
+class CmdLineTxt:
+    """
+    Represents operations on a `cmdline.txt` configuration file.
+
+    This class provides functionality to read, modify, and save the
+    `cmdline.txt` file commonly used for system configurations. It allows
+    setting key-value pairs, removing keys, and manages file locking to ensure
+    thread-safe modifications.
+    """
+
+    # Value is optional, "?:=" non-capturing the "="
+    re_name_value = re.compile(r"(?P<key>[^\s=]+)(?:=(?P<value>\S+))?")
+
+    def __init__(self):
+        self._cmdline_txt_path = ""
+        for path in CONFIG_TXT_LOCATIONS:
+            if exists(path):
+                self._cmdline_txt_path = path
+                break
+
+        if not self._cmdline_txt_path:
+            raise FileNotFoundError("no config.txt found")
+
+    def _get_cmdline_dict(self) -> dict:
+        with CMDLINE_TXT_LOCK:
+            with open(self._cmdline_txt_path, "r") as file:
+                cmdline = file.read()
+
+        return {
+            match.group("key"): match.group("value")
+            for match in self.re_name_value.finditer(cmdline)
+        }
+
+    def _write_cmdline_dict(self, cmdline_dict: dict) -> None:
+        with CMDLINE_TXT_LOCK:
+
+            tmp_path = f"{self._cmdline_txt_path}.tmp"
+            with open(tmp_path, "w") as file:
+                str_cmdline = ""
+                for key, value in cmdline_dict.items():
+                    if value is None:
+                        str_cmdline += f"{key} "
+                    else:
+                        str_cmdline += f"{key}={value} "
+
+                str_cmdline = str_cmdline.strip()
+                file.write(str_cmdline + "\n")
+
+            shutil.move(tmp_path, self._cmdline_txt_path)
+
+    def remove_key(self, key: str) -> None:
+        """
+        Removes a specified key from the config.txt file.
+
+        Parameters:
+        key: str
+            The key to be removed from the config.txt file.
+        """
+        dc_cmdline = self._get_cmdline_dict()
+        if key in dc_cmdline:
+            del dc_cmdline[key]
+            self._write_cmdline_dict(dc_cmdline)
+
+    def set_key_value(self, key: str, value: Optional[str] = None) -> None:
+        """
+        Sets a given key-value pair in the config.txt file. If the key does not
+        exist or the value differs from the current one, the pair is updated.
+        If the value is None, just the key is set without a value.
+
+        Parameters:
+        key: str
+            The key to set in the config.txt file.
+        value: Optional[str], default = None
+            The value to associate with the key, defaulting to None.
+        """
+        dc_cmdline = self._get_cmdline_dict()
+        if key not in dc_cmdline or dc_cmdline.get(key, value) != value:
+            dc_cmdline[key] = value
+            self._write_cmdline_dict(dc_cmdline)
+
+
 class ConfigTxt:
     """
     Configuration file handler for managing 'config.txt'.