Make OTBR use same channel as ZHA (#88546)

homeassistant/components/otbr/util.py

@@ -0,0 +1,43 @@
+"""Utility functions for the Open Thread Border Router integration."""
+from __future__ import annotations
+
+import contextlib
+
+from homeassistant.components.homeassistant_hardware.silabs_multiprotocol_addon import (
+    is_multiprotocol_url,
+)
+from homeassistant.components.zha import api as zha_api
+from homeassistant.core import HomeAssistant
+
+
+def _get_zha_url(hass: HomeAssistant) -> str | None:
+    """Get ZHA radio path, or None if there's no ZHA config entry."""
+    with contextlib.suppress(ValueError):
+        return zha_api.async_get_radio_path(hass)
+    return None
+
+
+async def _get_zha_channel(hass: HomeAssistant) -> int | None:
+    """Get ZHA channel, or None if there's no ZHA config entry."""
+    zha_network_settings: zha_api.NetworkBackup | None
+    with contextlib.suppress(ValueError):
+        zha_network_settings = await zha_api.async_get_network_settings(hass)
+    if not zha_network_settings:
+        return None
+    channel: int = zha_network_settings.network_info.channel
+    # ZHA uses channel 0 when no channel is set
+    return channel or None
+
+
+async def get_allowed_channel(hass: HomeAssistant, otbr_url: str) -> int | None:
+    """Return the allowed channel, or None if there's no restriction."""
+    if not is_multiprotocol_url(otbr_url):
+        # The OTBR is not sharing the radio, no restriction
+        return None
+
+    zha_url = _get_zha_url(hass)
+    if not zha_url or not is_multiprotocol_url(zha_url):
+        # ZHA is not configured or not sharing the radio with this OTBR, no restriction
+        return None
+
+    return await _get_zha_channel(hass)