[bk72xx_ble] Codegen-sized StaticVector for scan listeners (#18055)

esphome/components/bk72xx_ble/__init__.py

@@ -24,6 +24,7 @@ from esphome.components import libretiny
 from esphome.components.libretiny.const import FAMILY_BK7231N, FAMILY_BK7238
 import esphome.config_validation as cv
 from esphome.const import CONF_ENABLE_ON_BOOT, CONF_ID
+from esphome.core import CORE, CoroPriority, coroutine_with_priority
 from esphome.types import ConfigType
 
 DEPENDENCIES = ["bk72xx"]
@@ -45,6 +46,23 @@ CONFIG_SCHEMA = cv.Schema(
 ).extend(cv.COMPONENT_SCHEMA)
 
 
+KEY_SCAN_LISTENER_COUNT = "bk72xx_ble_scan_listener_count"
+
+
+def request_scan_listener_slot() -> None:
+    """Called from a consumer's codegen once per registered scan listener; sizes
+    the controller's StaticVector listener storage (heap-free, mirrors the
+    tracker's ble_device_base listener storage)."""
+    CORE.data[KEY_SCAN_LISTENER_COUNT] = CORE.data.get(KEY_SCAN_LISTENER_COUNT, 0) + 1
+
+
+@coroutine_with_priority(CoroPriority.FINAL)
+async def _add_listener_count() -> None:
+    # FINAL: every consumer's to_code has requested its slot by now.
+    if count := CORE.data.get(KEY_SCAN_LISTENER_COUNT, 0):
+        cg.add_define("BK72XX_BLE_SCAN_LISTENER_COUNT", count)
+
+
 async def to_code(config: ConfigType) -> None:
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
@@ -92,3 +110,5 @@ async def to_code(config: ConfigType) -> None:
         )
 
     cg.add_define("USE_BK72XX_BLE")
+
+    CORE.add_job(_add_listener_count)

esphome/components/bk72xx_ble/bk72xx_ble.cpp

@@ -179,8 +179,10 @@ void BK72xxBLE::loop() {
   if (report == nullptr)
     return;
   do {
+#ifdef BK72XX_BLE_SCAN_LISTENER_COUNT
     for (auto *listener : this->scan_listeners_)
       listener->on_scan_report(*report);
+#endif
     this->report_pool_.release(report);
   } while ((report = this->report_queue_.pop()) != nullptr);
 

esphome/components/bk72xx_ble/bk72xx_ble.h

@@ -6,10 +6,10 @@
 
 #include "esphome/core/component.h"
 #include "esphome/core/event_pool.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/lock_free_queue.h"
 
 #include <cstdint>
-#include <vector>
 
 namespace esphome::bk72xx_ble {
 
@@ -62,8 +62,12 @@ class BK72xxBLE final : public Component {
   /// Controller BLE address, least-significant octet first (BLE convention).
   void get_mac_lsb_first(uint8_t out[6]) const;
 
+#ifdef BK72XX_BLE_SCAN_LISTENER_COUNT
   /// Register a consumer for scan reports (delivered on the main task via loop()).
+  /// Storage is codegen-sized: the consumer's codegen requests a slot via
+  /// request_scan_listener_slot(), which emits BK72XX_BLE_SCAN_LISTENER_COUNT.
   void register_scan_listener(BLEScanListener *listener) { this->scan_listeners_.push_back(listener); }
+#endif
 
   /// Start the controller scan. Interval/window are in BLE units (0.625 ms).
   /// Enables the stack first if needed. Returns false on controller failure.
@@ -78,7 +82,11 @@ class BK72xxBLE final : public Component {
  protected:
   void resolve_mac_();
 
-  std::vector<BLEScanListener *> scan_listeners_;
+#ifdef BK72XX_BLE_SCAN_LISTENER_COUNT
+  // Codegen-sized: no heap allocation, no std::vector template instantiation —
+  // the same StaticVector pattern as the tracker's ble_device_base listeners.
+  StaticVector<BLEScanListener *, BK72XX_BLE_SCAN_LISTENER_COUNT> scan_listeners_;
+#endif
   // Report ring: the BDK notice callback (BLE task) allocates a report from the
   // pool, fills it and pushes the pointer; loop() pops, dispatches and releases.
   // Lock-free SPSC, zero allocation at steady state — the esp32_ble pattern.

esphome/components/bk72xx_ble_tracker/__init__.py

@@ -69,6 +69,9 @@ async def to_code(config: ConfigType) -> None:
 
     parent = await cg.get_variable(config[CONF_BK72XX_BLE_ID])
     cg.add(var.set_parent(parent))
+    # The tracker registers itself as a controller scan listener in setup();
+    # request the codegen-sized StaticVector slot for it.
+    bk72xx_ble.request_scan_listener_slot()
 
     # Get notified when an OTA update starts, to pause scanning (esp32_ble_tracker parity)
     ota.request_ota_state_listeners()

esphome/core/defines.h

@@ -454,6 +454,7 @@
 
 #ifdef USE_LIBRETINY
 #define USE_BK72XX_BLE
+#define BK72XX_BLE_SCAN_LISTENER_COUNT 1
 #define USE_LN882H_BLE
 #define LN882H_BLE_SCAN_LISTENER_COUNT 1
 #define USE_CAPTIVE_PORTAL