[wifi] Restore blocking setup until connected for RP2040 (#12142)

esphome/components/wifi/wifi_component.cpp

@@ -1612,6 +1612,20 @@ void WiFiComponent::retry_connect() {
   }
 }
 
+#ifdef USE_RP2040
+// RP2040's mDNS library (LEAmDNS) relies on LwipIntf::stateUpCB() to restart
+// mDNS when the network interface reconnects. However, this callback is disabled
+// in the arduino-pico framework. As a workaround, we block component setup until
+// WiFi is connected, ensuring mDNS.begin() is called with an active connection.
+
+bool WiFiComponent::can_proceed() {
+  if (!this->has_sta() || this->state_ == WIFI_COMPONENT_STATE_DISABLED || this->ap_setup_) {
+    return true;
+  }
+  return this->is_connected();
+}
+#endif
+
 void WiFiComponent::set_reboot_timeout(uint32_t reboot_timeout) { this->reboot_timeout_ = reboot_timeout; }
 bool WiFiComponent::is_connected() {
   return this->state_ == WIFI_COMPONENT_STATE_STA_CONNECTED &&

esphome/components/wifi/wifi_component.h

@@ -284,6 +284,10 @@ class WiFiComponent : public Component {
 
   void retry_connect();
 
+#ifdef USE_RP2040
+  bool can_proceed() override;
+#endif
+
   void set_reboot_timeout(uint32_t reboot_timeout);
 
   bool is_connected();