Surface ACL disconnect reasons from native to Java

HCI disconnect commands and events have an accompanying "reason"
parameter comprising of a HCI error code. This can be useful in both
debugging and re-connection logic at the Java level.

This CL grabs the HCI codes from native and passes it up to Java via an
extra parameter to existing ACL connection callbacks.

Tag: #feature
Bug: 177668957
Test: atest net_test_bluetooth # verify no regressions
Test: atest bluetoothtbd_test # verify no regressions
Test: atest bt_headless # verify test still builds
Test: manually disconnect local and remote devices and check logcats
from Java layer for disconnect reasons

Change-Id: Idcb1711345b515c5f60e55430352f5f4ff252d69

13 files changed, 39 insertions, 22 deletions

diff --git a/system/binder/android/bluetooth/IBluetoothConnectionCallback.aidl b/system/binder/android/bluetooth/IBluetoothConnectionCallback.aidl
index 8242c61b03..56de49c519 100644
--- a/system/binder/android/bluetooth/IBluetoothConnectionCallback.aidl
+++ b/system/binder/android/bluetooth/IBluetoothConnectionCallback.aidl
@@ -23,5 +23,5 @@ import android.bluetooth.BluetoothDevice;
  */
 oneway interface IBluetoothConnectionCallback {
     void onDeviceConnected(in BluetoothDevice device);
-    void onDeviceDisconnected(in BluetoothDevice device);
+    void onDeviceDisconnected(in BluetoothDevice device, in int hciReason);
 }
diff --git a/system/btif/include/btif_common.h b/system/btif/include/btif_common.h
index 4b749c5198..ea3ead6edf 100644
--- a/system/btif/include/btif_common.h
+++ b/system/btif/include/btif_common.h
@@ -210,7 +210,7 @@ void invoke_ssp_request_cb(RawAddress bd_addr, bt_bdname_t bd_name,
 void invoke_bond_state_changed_cb(bt_status_t status, RawAddress bd_addr,
                                   bt_bond_state_t state);
 void invoke_acl_state_changed_cb(bt_status_t status, RawAddress bd_addr,
-                                 bt_acl_state_t state);
+                                 bt_acl_state_t state, bt_hci_error_code_t hci_reason);
 void invoke_thread_evt_cb(bt_cb_thread_evt event);
 void invoke_le_test_mode_cb(bt_status_t status, uint16_t count);
 void invoke_energy_info_cb(bt_activity_energy_info energy_info,
diff --git a/system/btif/src/bluetooth.cc b/system/btif/src/bluetooth.cc
index 33c708fbec..1cbfb260b7 100644
--- a/system/btif/src/bluetooth.cc
+++ b/system/btif/src/bluetooth.cc
@@ -724,15 +724,16 @@ void invoke_bond_state_changed_cb(bt_status_t status, RawAddress bd_addr,
 }
 
 void invoke_acl_state_changed_cb(bt_status_t status, RawAddress bd_addr,
-                                 bt_acl_state_t state) {
+                                 bt_acl_state_t state, bt_hci_error_code_t hci_reason) {
   do_in_jni_thread(
       FROM_HERE,
       base::BindOnce(
-          [](bt_status_t status, RawAddress bd_addr, bt_acl_state_t state) {
+          [](bt_status_t status, RawAddress bd_addr, bt_acl_state_t state,
+             bt_hci_error_code_t hci_reason) {
             HAL_CBACK(bt_hal_cbacks, acl_state_changed_cb, status, &bd_addr,
-                      state);
+                      state, hci_reason);
           },
-          status, bd_addr, state));
+          status, bd_addr, state, hci_reason));
 }
 
 void invoke_thread_evt_cb(bt_cb_thread_evt event) {
diff --git a/system/btif/src/btif_dm.cc b/system/btif/src/btif_dm.cc
index 1f9549215d..0b8d3199f4 100644
--- a/system/btif/src/btif_dm.cc
+++ b/system/btif/src/btif_dm.cc
@@ -1532,7 +1532,7 @@ static void btif_dm_upstreams_evt(uint16_t event, char* p_param) {
       btif_update_remote_version_property(&bd_addr);
 
       invoke_acl_state_changed_cb(BT_STATUS_SUCCESS, bd_addr,
-                                  BT_ACL_STATE_CONNECTED);
+                                  BT_ACL_STATE_CONNECTED, HCI_SUCCESS);
       break;
 
     case BTA_DM_LINK_DOWN_EVT:
@@ -1543,7 +1543,8 @@ static void btif_dm_upstreams_evt(uint16_t event, char* p_param) {
       BTIF_TRACE_DEBUG(
           "BTA_DM_LINK_DOWN_EVT. Sending BT_ACL_STATE_DISCONNECTED");
       invoke_acl_state_changed_cb(BT_STATUS_SUCCESS, bd_addr,
-                                  BT_ACL_STATE_DISCONNECTED);
+                                  BT_ACL_STATE_DISCONNECTED,
+                                  static_cast<bt_hci_error_code_t>(btm_get_acl_disc_reason_code()));
       break;
 
     case BTA_DM_BLE_KEY_EVT:
diff --git a/system/include/hardware/bluetooth.h b/system/include/hardware/bluetooth.h
index e45340e37a..6d081f141a 100644
--- a/system/include/hardware/bluetooth.h
+++ b/system/include/hardware/bluetooth.h
@@ -135,6 +135,10 @@ inline std::string bt_status_text(const bt_status_t& status) {
   }
 }
 
+/** Bluetooth HCI Error Codes */
+/** Corresponding to [Vol 2] Part D, "Error Codes" of Core_v5.1 specs */
+typedef uint8_t bt_hci_error_code_t;
+
 /** Bluetooth PinKey Code */
 typedef struct { uint8_t pin[16]; } __attribute__((packed)) bt_pin_code_t;
 
@@ -423,7 +427,8 @@ typedef void (*bond_state_changed_callback)(bt_status_t status,
 /** Bluetooth ACL connection state changed callback */
 typedef void (*acl_state_changed_callback)(bt_status_t status,
                                            RawAddress* remote_bd_addr,
-                                           bt_acl_state_t state);
+                                           bt_acl_state_t state,
+                                           bt_hci_error_code_t hci_reason);
 
 /** Bluetooth link quality report callback */
 typedef void (*link_quality_report_callback)(
diff --git a/system/service/adapter.cc b/system/service/adapter.cc
index 1724fcdfed..d7964d2d92 100644
--- a/system/service/adapter.cc
+++ b/system/service/adapter.cc
@@ -683,7 +683,8 @@ class AdapterImpl : public Adapter, public hal::BluetoothInterface::Observer {
 
   void AclStateChangedCallback(bt_status_t status,
                                const RawAddress& remote_bdaddr,
-                               bt_acl_state_t state) override {
+                               bt_acl_state_t state,
+                               bt_hci_error_code_t hci_reason) override {
     std::string device_address = BtAddrString(&remote_bdaddr);
     bool connected = (state == BT_ACL_STATE_CONNECTED);
     LOG(INFO) << "ACL state changed: " << device_address
diff --git a/system/service/hal/bluetooth_interface.cc b/system/service/hal/bluetooth_interface.cc
index 6a2118e509..3afe635c53 100644
--- a/system/service/hal/bluetooth_interface.cc
+++ b/system/service/hal/bluetooth_interface.cc
@@ -147,16 +147,17 @@ void BondStateChangedCallback(bt_status_t status, RawAddress* remote_bd_addr,
 }
 
 void AclStateChangedCallback(bt_status_t status, RawAddress* remote_bd_addr,
-                             bt_acl_state_t state) {
+                             bt_acl_state_t state, bt_hci_error_code_t hci_reason) {
   shared_lock<shared_mutex_impl> lock(g_instance_lock);
   VERIFY_INTERFACE_OR_RETURN();
   CHECK(remote_bd_addr);
   VLOG(1) << "Remote device ACL state changed - status: "
           << BtStatusText(status)
           << " - BD_ADDR: " << BtAddrString(remote_bd_addr) << " - state: "
-          << ((state == BT_ACL_STATE_CONNECTED) ? "CONNECTED" : "DISCONNECTED");
+          << ((state == BT_ACL_STATE_CONNECTED) ? "CONNECTED" : "DISCONNECTED")
+          << " - HCI_REASON: " << std::to_string(hci_reason);
   FOR_EACH_BLUETOOTH_OBSERVER(
-      AclStateChangedCallback(status, *remote_bd_addr, state));
+      AclStateChangedCallback(status, *remote_bd_addr, state, hci_reason));
 }
 
 void ThreadEventCallback(bt_cb_thread_evt evt) {
@@ -364,7 +365,7 @@ void BluetoothInterface::Observer::BondStateChangedCallback(
 
 void BluetoothInterface::Observer::AclStateChangedCallback(
     bt_status_t /* status */, const RawAddress& /* remote_bdaddr */,
-    bt_acl_state_t /* state */) {
+    bt_acl_state_t /* state */, bt_hci_error_code_t /* hci_reason */) {
   // Do nothing.
 }
 
diff --git a/system/service/hal/bluetooth_interface.h b/system/service/hal/bluetooth_interface.h
index bdd8005b74..aa4125cc90 100644
--- a/system/service/hal/bluetooth_interface.h
+++ b/system/service/hal/bluetooth_interface.h
@@ -72,7 +72,8 @@ class BluetoothInterface {
                                           bt_bond_state_t state);
     virtual void AclStateChangedCallback(bt_status_t status,
                                          const RawAddress& remote_bdaddr,
-                                         bt_acl_state_t state);
+                                         bt_acl_state_t state,
+                                         bt_hci_error_code_t hci_reason);
     virtual void LinkQualityReportCallback(
         uint64_t timestamp, int report_id, int rssi, int snr,
         int retransmission_count, int packets_not_receive_count,
diff --git a/system/service/hal/fake_bluetooth_interface.cc b/system/service/hal/fake_bluetooth_interface.cc
index 5427d9131a..cf6123d9f4 100644
--- a/system/service/hal/fake_bluetooth_interface.cc
+++ b/system/service/hal/fake_bluetooth_interface.cc
@@ -141,9 +141,10 @@ void FakeBluetoothInterface::NotifyAdapterLocalLeFeaturesPropertyChanged(
 }
 
 void FakeBluetoothInterface::NotifyAclStateChangedCallback(
-    bt_status_t status, const RawAddress& remote_bdaddr, bt_acl_state_t state) {
+    bt_status_t status, const RawAddress& remote_bdaddr, bt_acl_state_t state,
+    bt_hci_error_code_t hci_reason) {
   for (auto& observer : observers_) {
-    observer.AclStateChangedCallback(status, remote_bdaddr, state);
+    observer.AclStateChangedCallback(status, remote_bdaddr, state, hci_reason);
   }
 }
 
diff --git a/system/service/hal/fake_bluetooth_interface.h b/system/service/hal/fake_bluetooth_interface.h
index 93ec076652..0fc0aa1976 100644
--- a/system/service/hal/fake_bluetooth_interface.h
+++ b/system/service/hal/fake_bluetooth_interface.h
@@ -57,7 +57,8 @@ class FakeBluetoothInterface : public BluetoothInterface {
       const bt_local_le_features_t* features);
   void NotifyAclStateChangedCallback(bt_status_t status,
                                      const RawAddress& remote_bdaddr,
-                                     bt_acl_state_t state);
+                                     bt_acl_state_t state,
+                                     bt_hci_error_code_t hci_reason);
 
   // hal::BluetoothInterface overrides:
   void AddObserver(Observer* observer) override;
diff --git a/system/service/test/adapter_unittest.cc b/system/service/test/adapter_unittest.cc
index b1cedc19c9..5abd08eee5 100644
--- a/system/service/test/adapter_unittest.cc
+++ b/system/service/test/adapter_unittest.cc
@@ -259,21 +259,24 @@ TEST_F(AdapterTest, IsDeviceConnected) {
 
   // status != BT_STATUS_SUCCESS should be ignored
   fake_hal_iface_->NotifyAclStateChangedCallback(BT_STATUS_FAIL, hal_addr,
-                                                 BT_ACL_STATE_CONNECTED);
+                                                 BT_ACL_STATE_CONNECTED,
+                                                 0xff); // HCI_ERR_UNDEFINED
   EXPECT_FALSE(adapter_->IsDeviceConnected(kDeviceAddr));
   EXPECT_TRUE(observer.last_connection_state_address().empty());
   EXPECT_FALSE(observer.last_device_connected_state());
 
   // Connected
   fake_hal_iface_->NotifyAclStateChangedCallback(BT_STATUS_SUCCESS, hal_addr,
-                                                 BT_ACL_STATE_CONNECTED);
+                                                 BT_ACL_STATE_CONNECTED,
+                                                 0x00); // HCI_SUCCESS
   EXPECT_TRUE(adapter_->IsDeviceConnected(kDeviceAddr));
   EXPECT_EQ(kDeviceAddr, observer.last_connection_state_address());
   EXPECT_TRUE(observer.last_device_connected_state());
 
   // Disconnected
   fake_hal_iface_->NotifyAclStateChangedCallback(BT_STATUS_SUCCESS, hal_addr,
-                                                 BT_ACL_STATE_DISCONNECTED);
+                                                 BT_ACL_STATE_DISCONNECTED,
+                                                 0x16); // HCI_ERR_CONN_CAUSE_LOCAL_HOST
   EXPECT_FALSE(adapter_->IsDeviceConnected(kDeviceAddr));
   EXPECT_EQ(kDeviceAddr, observer.last_connection_state_address());
   EXPECT_FALSE(observer.last_device_connected_state());
diff --git a/system/test/headless/headless.cc b/system/test/headless/headless.cc
index 11b05a43f1..31a9687ff1 100644
--- a/system/test/headless/headless.cc
+++ b/system/test/headless/headless.cc
@@ -103,7 +103,7 @@ void bond_state_changed(bt_status_t status, RawAddress* remote_bd_addr,
 
 /** Bluetooth ACL connection state changed callback */
 void acl_state_changed(bt_status_t status, RawAddress* remote_bd_addr,
-                       bt_acl_state_t state) {
+                       bt_acl_state_t state, bt_hci_error_code_t hci_reason) {
   auto callback_list = interface_api_callback_map_.at(__func__);
   for (auto callback : callback_list) {
     interface_data_t params{
@@ -111,6 +111,7 @@ void acl_state_changed(bt_status_t status, RawAddress* remote_bd_addr,
         .params.acl_state_changed.status = status,
         .params.acl_state_changed.remote_bd_addr = remote_bd_addr,
         .params.acl_state_changed.state = state,
+        .params.acl_state_changed.hci_reason = hci_reason,
     };
     (callback)(params);
   }
diff --git a/system/test/headless/interface.h b/system/test/headless/interface.h
index d2dd58c07e..d79016a7fc 100644
--- a/system/test/headless/interface.h
+++ b/system/test/headless/interface.h
@@ -12,6 +12,7 @@ using acl_state_changed_params_t = struct {
   bt_status_t status;
   RawAddress* remote_bd_addr;
   bt_acl_state_t state;
+  bt_hci_error_code_t hci_reason;
 };
 
 using callback_params_t = union {