[wifi] Use queue abstraction for LibreTiny WiFi events

Replace static FreeRTOS queue globals in the LibreTiny WiFi component
with the same queue abstraction used by ESP32:

- ESPHOME_THREAD_MULTI_ATOMICS (RTL87xx, LN882x): LockFreeQueue
- ESPHOME_THREAD_MULTI_NO_ATOMICS (BK72xx): new FreeRTOSQueue wrapper

Add FreeRTOSQueue in freertos_queue.h — an xQueue wrapper providing
the same API as LockFreeQueue (push, pop, get_and_reset_dropped_count)
for platforms without hardware atomic instructions.

The event queue is now a class member instead of a static global,
matching the ESP32 pattern.

esphome/components/wifi/wifi_component.h

@@ -9,6 +9,11 @@
 #ifdef USE_ESP32
 #include "esphome/core/lock_free_queue.h"
 #endif
+#if defined(USE_LIBRETINY) && defined(ESPHOME_THREAD_MULTI_ATOMICS)
+#include "esphome/core/lock_free_queue.h"
+#elif defined(USE_LIBRETINY) && defined(ESPHOME_THREAD_MULTI_NO_ATOMICS)
+#include "esphome/core/freertos_queue.h"
+#endif
 #include "esphome/core/string_ref.h"
 
 #include <span>
@@ -882,6 +887,17 @@ class WiFiComponent final : public Component {
   LockFreeQueue<IDFWiFiEvent, 17> event_queue_;
 #endif
 
+#ifdef USE_LIBRETINY
+  // Thread-safe queue for WiFi events from LibreTiny callback thread.
+  // LockFreeQueue on platforms with hardware atomics (RTL87xx, LN882x),
+  // FreeRTOSQueue on platforms without (BK72xx).
+#ifdef ESPHOME_THREAD_MULTI_ATOMICS
+  LockFreeQueue<LTWiFiEvent, 17> event_queue_;
+#else
+  FreeRTOSQueue<LTWiFiEvent, 16> event_queue_;
+#endif
+#endif
+
  private:
   // Stores a pointer to a string literal (static storage duration).
   // ONLY set from Python-generated code with string literals - never dynamic strings.

esphome/components/wifi/wifi_component_libretiny.cpp

@@ -10,9 +10,6 @@
 #include "lwip/err.h"
 #include "lwip/dns.h"
 
-#include <FreeRTOS.h>
-#include <queue.h>
-
 #ifdef USE_BK72XX
 extern "C" {
 #include <wlan_ui_pub.h>
@@ -43,16 +40,13 @@ static const char *const TAG = "wifi_lt";
 // (like connection status flags) from the callback causes race conditions:
 // - The main loop may never see state changes (values cached in registers)
 // - State changes may be visible in inconsistent order
-// - LibreTiny targets (BK7231, RTL8720) lack atomic instructions (no LDREX/STREX)
 //
 // Solution: Queue events in the callback and process them in the main loop.
 // This is the same approach used by ESP32 IDF's wifi_process_event_().
 // All state modifications happen in the main loop context, eliminating races.
-
-static constexpr size_t EVENT_QUEUE_SIZE = 16;  // Max pending WiFi events before overflow
-static QueueHandle_t s_event_queue = nullptr;   // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
-static volatile uint32_t s_event_queue_overflow_count =
-    0;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+//
+// On platforms with hardware atomics (RTL87xx, LN882x): LockFreeQueue (SPSC ring buffer)
+// On platforms without (BK72xx): FreeRTOSQueue (xQueue wrapper with critical sections)
 
 // Event structure for queued WiFi events - contains a copy of event data
 // to avoid lifetime issues with the original event data from the callback
@@ -352,10 +346,6 @@ using esphome_wifi_event_info_t = arduino_event_info_t;
 // Event callback - runs in WiFi driver thread context
 // Only queues events for processing in main loop, no logging or state changes here
 void WiFiComponent::wifi_event_callback_(esphome_wifi_event_id_t event, esphome_wifi_event_info_t info) {
-  if (s_event_queue == nullptr) {
-    return;
-  }
-
   // Allocate on heap and fill directly to avoid extra memcpy
   auto *to_send = new LTWiFiEvent{};  // NOLINT(cppcoreguidelines-owning-memory)
   to_send->event_id = event;
@@ -428,9 +418,8 @@ void WiFiComponent::wifi_event_callback_(esphome_wifi_event_id_t event, esphome_
   }
 
   // Queue event (don't block if queue is full)
-  if (xQueueSend(s_event_queue, &to_send, 0) != pdPASS) {
+  if (!this->event_queue_.push(to_send)) {
     delete to_send;  // NOLINT(cppcoreguidelines-owning-memory)
-    s_event_queue_overflow_count++;
   }
 }
 
@@ -620,14 +609,6 @@ void WiFiComponent::wifi_process_event_(LTWiFiEvent *event) {
   }
 }
 void WiFiComponent::wifi_pre_setup_() {
-  // Create event queue for thread-safe event handling
-  // Events are pushed from WiFi callback thread and processed in main loop
-  s_event_queue = xQueueCreate(EVENT_QUEUE_SIZE, sizeof(LTWiFiEvent *));
-  if (s_event_queue == nullptr) {
-    ESP_LOGE(TAG, "Failed to create event queue");
-    return;
-  }
-
   WiFi.onEvent(
       [this](arduino_event_id_t event, arduino_event_info_t info) { this->wifi_event_callback_(event, info); });
   // Make sure WiFi is in clean state before anything starts
@@ -797,24 +778,14 @@ network::IPAddress WiFiComponent::wifi_subnet_mask_() { return {WiFi.subnetMask(
 network::IPAddress WiFiComponent::wifi_gateway_ip_() { return {WiFi.gatewayIP()}; }
 network::IPAddress WiFiComponent::wifi_dns_ip_(int num) { return {WiFi.dnsIP(num)}; }
 void WiFiComponent::wifi_loop_() {
-  // Process all pending events from the queue
-  if (s_event_queue == nullptr) {
-    return;
-  }
-
   // Check for dropped events due to queue overflow
-  if (s_event_queue_overflow_count > 0) {
-    ESP_LOGW(TAG, "Event queue overflow, %" PRIu32 " events dropped", s_event_queue_overflow_count);
-    s_event_queue_overflow_count = 0;
+  uint16_t dropped = this->event_queue_.get_and_reset_dropped_count();
+  if (dropped > 0) {
+    ESP_LOGW(TAG, "Dropped %" PRIu16 " WiFi events due to buffer overflow", dropped);
   }
 
-  while (true) {
-    LTWiFiEvent *event;
-    if (xQueueReceive(s_event_queue, &event, 0) != pdTRUE) {
-      // No more events
-      break;
-    }
-
+  LTWiFiEvent *event;
+  while ((event = this->event_queue_.pop()) != nullptr) {
     wifi_process_event_(event);
     delete event;  // NOLINT(cppcoreguidelines-owning-memory)
   }

esphome/core/freertos_queue.h

@@ -0,0 +1,82 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+
+#include <FreeRTOS.h>
+#include <queue.h>
+
+/*
+ * FreeRTOS queue wrapper for single-producer single-consumer scenarios on
+ * platforms without hardware atomic support (e.g. BK72xx ARM968E-S).
+ *
+ * Provides the same API as LockFreeQueue (push, pop, get_and_reset_dropped_count,
+ * empty, full, size) but uses xQueue internally, which synchronizes via
+ * FreeRTOS critical sections.
+ *
+ * @tparam T The type of elements stored in the queue (stored as pointers)
+ * @tparam SIZE The maximum number of elements
+ */
+
+namespace esphome {
+
+template<class T, uint8_t SIZE> class FreeRTOSQueue {
+ public:
+  FreeRTOSQueue() : dropped_count_(0) { this->handle_ = xQueueCreate(SIZE, sizeof(T *)); }
+
+  bool push(T *element) {
+    if (element == nullptr || this->handle_ == nullptr)
+      return false;
+
+    if (xQueueSend(this->handle_, &element, 0) != pdPASS) {
+      this->dropped_count_++;
+      return false;
+    }
+    return true;
+  }
+
+  T *pop() {
+    if (this->handle_ == nullptr)
+      return nullptr;
+
+    T *element;
+    if (xQueueReceive(this->handle_, &element, 0) != pdTRUE) {
+      return nullptr;
+    }
+    return element;
+  }
+
+  uint16_t get_and_reset_dropped_count() {
+    uint16_t count = this->dropped_count_;
+    if (count == 0)
+      return 0;
+    this->dropped_count_ = 0;
+    return count;
+  }
+
+  void increment_dropped_count() { this->dropped_count_++; }
+
+  bool empty() const {
+    if (this->handle_ == nullptr)
+      return true;
+    return uxQueueMessagesWaiting(this->handle_) == 0;
+  }
+
+  bool full() const {
+    if (this->handle_ == nullptr)
+      return true;
+    return uxQueueSpacesAvailable(this->handle_) == 0;
+  }
+
+  size_t size() const {
+    if (this->handle_ == nullptr)
+      return 0;
+    return uxQueueMessagesWaiting(this->handle_);
+  }
+
+ protected:
+  QueueHandle_t handle_;
+  volatile uint16_t dropped_count_;
+};
+
+}  // namespace esphome