[ESP32]: Add way to configure BLE scan response. (#28571)

* [ESP32]: Add way to configure scan response.

* Restyled by prettier-markdown

* Address review comments

---------

Co-authored-by: Restyled.io <commits@restyled.io>

Author: 2 people

docs/guides/esp32/README.md

@@ -17,3 +17,4 @@ example on ESP32 series of SoCs
 -   [RPC Console and Device Tracing](rpc_console.md)
 -   [Matter OTA](ota.md)
 -   [Generating and Using ESP Secure Cert Partition](secure_cert_partition.md)
+-   [BLE Settings](ble_settings.md)

docs/guides/esp32/ble_settings.md

@@ -0,0 +1,32 @@
+# Bluetooth Low Energy (BLE)
+
+## Nimble: scan response
+
+The `ConfigureScanResponseData` API is used to configure the scan response data
+for advertising in a Bluetooth Low Energy (BLE) application based on the NimBLE
+BLE stack. Scan response data is additional data that a BLE peripheral device
+can include in its advertising packets to provide more information about itself.
+This API allows you to set the scan response data that will be included in the
+advertising packets.
+
+### Usage
+
+```
+{
+    uint8_t scanResponse[31]; // 0x05, 0x09, a, b, c, d
+    scanResponse[0] = 0x05;
+    scanResponse[1] = 0x09;
+    scanResponse[2] = 0x61;
+    scanResponse[3] = 0x62;
+    scanResponse[4] = 0x63;
+    scanResponse[5] = 0x64;
+    chip::ByteSpan data(scanResponse);
+    CHIP_ERROR err = chip::DeviceLayer::Internal::BLEMgrImpl().ConfigureScanResponseData(data);
+    if (err != CHIP_NO_ERROR)
+    {
+        ESP_LOGE(TAG, "Failed to configure scan response, err:%" CHIP_ERROR_FORMAT, err.Format());
+    }
+}
+```
+
+Note: Scan response should be configure before `InitServer`.

src/platform/ESP32/BLEManagerImpl.h

@@ -71,6 +71,8 @@ struct ble_gatt_char_context
 #include <platform/ESP32/ChipDeviceScanner.h>
 #endif
 
+#define MAX_SCAN_RSP_DATA_LEN 31
+
 namespace chip {
 namespace DeviceLayer {
 namespace Internal {
@@ -132,6 +134,7 @@ class BLEManagerImpl final : public BLEManager,
 #endif
 {
 public:
+    uint8_t scanResponseBuffer[MAX_SCAN_RSP_DATA_LEN];
     BLEManagerImpl() {}
 #if CONFIG_ENABLE_ESP32_BLE_CONTROLLER
     CHIP_ERROR ConfigureBle(uint32_t aAdapterId, bool aIsCentral);
@@ -140,7 +143,12 @@ class BLEManagerImpl final : public BLEManager,
 #endif
 #endif
 
+    CHIP_ERROR ConfigureScanResponseData(ByteSpan data);
+    void ClearScanResponseData(void);
+
 private:
+    chip::Optional<chip::ByteSpan> mScanResponse;
+
     // Allow the BLEManager interface class to delegate method calls to
     // the implementation methods provided by this class.
     friend BLEManager;

src/platform/ESP32/nimble/BLEManagerImpl.cpp

@@ -1012,6 +1012,25 @@ CHIP_ERROR BLEManagerImpl::ConfigureAdvertisingData(void)
     return err;
 }
 
+CHIP_ERROR BLEManagerImpl::ConfigureScanResponseData(ByteSpan data)
+{
+    if (!IsSpanUsable(data) || data.size() > MAX_SCAN_RSP_DATA_LEN)
+    {
+        ChipLogError(DeviceLayer, "scan response data is invalid");
+        return CHIP_ERROR_INVALID_ARGUMENT;
+    }
+    memcpy(scanResponseBuffer, data.data(), data.size());
+    ByteSpan scanResponseSpan(scanResponseBuffer);
+    mScanResponse = chip::Optional(scanResponseSpan);
+    return CHIP_NO_ERROR;
+}
+
+void BLEManagerImpl::ClearScanResponseData(void)
+{
+    mScanResponse.ClearValue();
+    ChipLogDetail(DeviceLayer, "scan response data is cleared");
+}
+
 void BLEManagerImpl::HandleRXCharWrite(struct ble_gatt_char_context * param)
 {
     CHIP_ERROR err    = CHIP_NO_ERROR;
@@ -1584,6 +1603,15 @@ CHIP_ERROR BLEManagerImpl::StartAdvertising(void)
             }
         }
 #endif
+        if (mScanResponse.HasValue())
+        {
+            err = MapBLEError(ble_gap_adv_rsp_set_data(mScanResponse.Value().data(), mScanResponse.Value().size()));
+            if (err != CHIP_NO_ERROR)
+            {
+                ChipLogError(DeviceLayer, "ble_gap_adv_rsp_set_data failed: %s", ErrorStr(err));
+                return err;
+            }
+        }
         err = MapBLEError(ble_gap_adv_start(own_addr_type, NULL, BLE_HS_FOREVER, &adv_params, ble_svr_gap_event, NULL));
         if (err == CHIP_NO_ERROR)
         {