feat(dbus): Add RevPiConfig class for device information handling

This commit introduces a new `RevPiConfig` class to manage RevPi device
configuration details, such as model, serial, compute module type, WiFi,
and ConBridge detection. It parses CPU info from `/proc/cpuinfo` and
leverages helper methods for hardware-specific checks, enhancing the
middleware's ability to identify and manage hardware features.

src/revpi_middleware/dbus_middleware1/system_config/revpi_config.py

@@ -0,0 +1,92 @@
+# -*- coding: utf-8 -*-
+# SPDX-FileCopyrightText: 2025 KUNBUS GmbH
+# SPDX-License-Identifier: GPL-2.0-or-later
+from enum import IntEnum
+from logging import getLogger
+
+from ..dbus_helper import grep
+
+log = getLogger(__name__)
+
+
+class ComputeModuleTypes(IntEnum):
+    UNKNOWN = 0
+    CM1 = 6
+    CM3 = 10
+    CM4 = 20
+    CM4S = 21
+    CM5 = 24
+
+
+class RevPiConfig:
+
+    def __init__(self):
+        self._cm_type = ComputeModuleTypes.UNKNOWN
+        self._cm_with_wifi = False
+
+        self._revpi_with_con_bridge = False
+
+        self.serial = ""
+        self.model = ""
+
+        self._init_device_info()
+
+    def _init_device_info(self):
+        dc_cpuinfo = {}
+
+        # Extract CPU information
+        with open("/proc/cpuinfo", "r") as f:
+            line = "\n"
+            while line:
+                line = f.readline()
+                if line.startswith(("Revision", "Serial", "Model")):
+                    key, value = line.split(":", 1)
+                    key = key.strip().lower()
+                    value = value.strip()
+                    dc_cpuinfo[key] = value
+
+        self.model = dc_cpuinfo.get("model", "")
+        self.serial = dc_cpuinfo.get("serial", "")
+
+        # Detect Compute Module type
+        revision = dc_cpuinfo.get("revision", "")
+        if revision:
+            revision = int(revision, 16)
+            mask = 4080  # 0xFF0 in dezimal
+            try:
+                self._cm_type = ComputeModuleTypes((revision & mask) >> 4)
+            except ValueError:
+                pass
+
+        # Detect WiFi
+        could_have_wifi = self._cm_type in (ComputeModuleTypes.CM4, ComputeModuleTypes.CM5)
+        if could_have_wifi:
+            lst_grep = grep("DRIVER=brcmfmac", "/sys/class/ieee80211/phy0/device/uevent")
+            self._cm_with_wifi = len(lst_grep) > 0 and self._cm_type in (ComputeModuleTypes)
+
+        # Detect ConBridge
+        could_have_con_bridge = self._cm_type in (ComputeModuleTypes.CM3, ComputeModuleTypes.CM4S)
+        if could_have_con_bridge:
+            lst_grep = grep("kunbus,revpi-connect", "/proc/device-tree/compatible")
+            self._revpi_with_con_bridge = len(lst_grep) > 0
+
+    @property
+    def cm_type(self) -> ComputeModuleTypes:
+        return self._cm_type
+
+    @property
+    def with_con_bridge(self) -> bool:
+        return self._revpi_with_con_bridge
+
+    @property
+    def with_wifi(self) -> bool:
+        return self._cm_with_wifi
+
+
+if __name__ == "__main__":
+    rc = RevPiConfig()
+    print("Model:", rc.model)
+    print("Serial:         ", rc.serial)
+    print("CM Type:        ", rc.cm_type.name)
+    print("With wifi:      ", rc.with_wifi)
+    print("With con-bridge:", rc.with_con_bridge)