Actually implement auto forming (untested, for now)

Author: puddly

tests/test_api.py

@@ -618,6 +618,28 @@ async def test_znp_nvram_writes(znp, event_loop):
         await znp.nvram_write(nvids.NwkNvIds.STARTUP_OPTION, t.uint8_t(0xAB))
 
 
+@pytest_mark_asyncio_timeout()
+async def test_znp_nvram_read_success(znp, event_loop):
+    event_loop.call_soon(
+        znp.frame_received,
+        c.Sys.OSALNVRead.Rsp(Status=t.Status.Success, Value=b"test",).to_frame(),
+    )
+    result = await znp.nvram_read(nvids.NwkNvIds.STARTUP_OPTION)
+
+    assert result == b"test"
+
+
+@pytest_mark_asyncio_timeout()
+async def test_znp_nvram_read_failure(znp, event_loop):
+    event_loop.call_soon(
+        znp.frame_received,
+        c.Sys.OSALNVRead.Rsp(Status=t.Status.Failure, Value=b"test",).to_frame(),
+    )
+
+    with pytest.raises(InvalidCommandResponse):
+        await znp.nvram_read(nvids.NwkNvIds.STARTUP_OPTION)
+
+
 @pytest_mark_asyncio_timeout()
 async def test_listeners_resolve(event_loop):
     callback = Mock()

zigpy_znp/api.py

@@ -350,3 +350,12 @@ async def nvram_write(
             c.Sys.OSALNVWrite.Req(Id=nv_id, Offset=offset, Value=t.ShortBytes(value)),
             RspStatus=t.Status.Success,
         )
+
+    async def nvram_read(
+        self, nv_id: nvids.BaseNvIds, *, offset: t.uint8_t = 0
+    ) -> bytes:
+        response = await self.request(
+            c.Sys.OSALNVRead.Req(Id=nv_id, Offset=offset), RspStatus=t.Status.Success,
+        )
+
+        return response.Value

zigpy_znp/zigbee/application.py

@@ -255,9 +255,15 @@ async def startup(self, auto_form=False):
 
         await self._reset()
 
-        if auto_form and False:
-            # XXX: actually form a network
-            await self.form_network()
+        if auto_form:
+            is_configured = await self._znp.nvram_read(NwkNvIds.HAS_CONFIGURED_ZSTACK3)
+
+            # This is some NVID that stores 0x55 (0b01010101) if the stack is configured
+            # It is not documented or present in the TI codebase, as far as I can tell.
+            if is_configured != b"\x55":
+                await self.form_network()
+            else:
+                LOGGER.info("ZNP is already configured, no need to form network.")
 
         if self.config[conf.CONF_ZNP_CONFIG][conf.CONF_TX_POWER] is not None:
             dbm = self.config[conf.CONF_ZNP_CONFIG][conf.CONF_TX_POWER]