android6.0 Bluetooth蓝牙源码流程笔记
注：基于mtk平台的android6.0,由于我个人水平有限，代码细节不能详细说明，抱歉
参考文章：
http://blog.csdn.net/shichaog/article/details/52728684
http://blog.csdn.net/baimy1985/article/details/8922508
http://blog.csdn.net/yanli0084/article/details/51821064
谢谢以上大佬
首先从BluetoothAdapter.enable开始
frameworks/base/core/java/android/bluetooth.BluetoothAdapter.java
public boolean enable() {
int state = STATE_OFF;
if (isEnabled() == true){
if (DBG) Log.d(TAG, "enable(): BT is already enabled..!");
return true;
}
//Use service interface to get the exact state
if (mService != null) {
try {
state = mService.getState();
} catch (RemoteException e) {Log.e(TAG, "", e);}
}
if (state == BluetoothAdapter.STATE_BLE_ON) {
Log.e(TAG, "BT is in BLE_ON State");
notifyUserAction(true);
return true;
}
try {
if (DBG) Log.d(TAG, "enable");
return mManagerService.enable();
} catch (RemoteException e) {Log.e(TAG, "", e);}
return false;
} public static synchronized BluetoothAdapter getDefaultAdapter() {
if (sAdapter == null) {
IBinder b = ServiceManager.getService(BLUETOOTH_MANAGER_SERVICE);
if (b != null) {
IBluetoothManager managerService = IBluetoothManager.Stub.asInterface(b);
sAdapter = new BluetoothAdapter(managerService);
} else {
Log.e(TAG, "Bluetooth binder is null");
}
}
return sAdapter;
}看来有个地方把binder注册成了BLUETOOTH_MANAGER_SERVICE，搜索发现在BluetoothService中
@Override
public void onStart() {
Log.d(TAG, "onStart: publishing BluetoothManagerService");
publishBinderService(BluetoothAdapter.BLUETOOTH_MANAGER_SERVICE, mBluetoothManagerService);
} public boolean enable() {
if ((Binder.getCallingUid() != Process.SYSTEM_UID) &&
(!checkIfCallerIsForegroundUser())) {
Log.w(TAG,"enable(): not allowed for non-active and non system user");
return false;
}
mContext.enforceCallingOrSelfPermission(BLUETOOTH_ADMIN_PERM,
"Need BLUETOOTH ADMIN permission");
if (DBG) {
Log.d(TAG,"enable(): mBluetooth =" + mBluetooth +
" mBinding = " + mBinding);
}
/// M: MoMS permission check @{
if (MobileManagerUtils.isSupported()) {
checkEnablePermission();
return true;
}
/// @}
synchronized(mReceiver) {
mQuietEnableExternal = false;
mEnableExternal = true;
// waive WRITE_SECURE_SETTINGS permission check
sendEnableMsg(false);
}
if (DBG) Log.d(TAG, "enable returning");
return true;
} private void sendEnableMsg(boolean quietMode) {
mHandler.sendMessage(mHandler.obtainMessage(MESSAGE_ENABLE,
quietMode ? 1 : 0, 0));
} case MESSAGE_ENABLE:
if (DBG) {
Log.d(TAG, "MESSAGE_ENABLE: mBluetooth = " + mBluetooth);
}
mHandler.removeMessages(MESSAGE_RESTART_BLUETOOTH_SERVICE);
mEnable = true;
handleEnable(msg.arg1 == 1);
break;
private void handleEnable(boolean quietMode) {
mQuietEnable = quietMode;
synchronized(mConnection) {
if (DBG) Log.d(TAG, "handleEnable: mBluetooth = " + mBluetooth +
", mBinding = " + mBinding + "quietMode = " + quietMode);
if ((mBluetooth == null) && (!mBinding)) {
if (DBG) Log.d(TAG, "Bind AdapterService");
//Start bind timeout and bind
Message timeoutMsg=mHandler.obtainMessage(MESSAGE_TIMEOUT_BIND);
mHandler.sendMessageDelayed(timeoutMsg,TIMEOUT_BIND_MS);
mConnection.setGetNameAddressOnly(false);
Intent i = new Intent(IBluetooth.class.getName());
if (!doBind(i, mConnection,Context.BIND_AUTO_CREATE | Context.BIND_IMPORTANT,
UserHandle.CURRENT)) {
mHandler.removeMessages(MESSAGE_TIMEOUT_BIND);
Log.e(TAG, "Fail to bind to: " + IBluetooth.class.getName());
} else {
mBinding = true;
}
} else if (mBluetooth != null) {
if (mConnection.isGetNameAddressOnly()) {
// if GetNameAddressOnly is set, we can clear this flag,
// so the service won't be unbind
// after name and address are saved
mConnection.setGetNameAddressOnly(false);
//Register callback object
try {
mBluetooth.registerCallback(mBluetoothCallback);
} catch (RemoteException re) {
Log.e(TAG, "Unable to register BluetoothCallback",re);
}
//Inform BluetoothAdapter instances that service is up
sendBluetoothServiceUpCallback();
}
//Enable bluetooth
try {
if (!mQuietEnable) {
if(!mBluetooth.enable()) {
Log.e(TAG,"IBluetooth.enable() returned false");
}
}
else {
if(!mBluetooth.enableNoAutoConnect()) {
Log.e(TAG,"IBluetooth.enableNoAutoConnect() returned false");
}
}
} catch (RemoteException e) {
Log.e(TAG,"Unable to call enable()",e);
}
}
}
} boolean doBind(Intent intent, ServiceConnection conn, int flags, UserHandle user) {
ComponentName comp = intent.resolveSystemService(mContext.getPackageManager(), 0);
intent.setComponent(comp);
if (comp == null || !mContext.bindServiceAsUser(intent, conn, flags, user)) {
Log.e(TAG, "Fail to bind to: " + intent);
return false;
}
return true;
}Manifest.xml
public void onServiceConnected(ComponentName className, IBinder service) {
if (DBG) Log.d(TAG, "BluetoothServiceConnection: " + className.getClassName());
Message msg = mHandler.obtainMessage(MESSAGE_BLUETOOTH_SERVICE_CONNECTED);
// TBD if (className.getClassName().equals(IBluetooth.class.getName())) {
if (className.getClassName().equals("com.android.bluetooth.btservice.AdapterService")) {
msg.arg1 = SERVICE_IBLUETOOTH;
// } else if (className.getClassName().equals(IBluetoothGatt.class.getName())) {
} else if (className.getClassName().equals("com.android.bluetooth.gatt.GattService")) {
msg.arg1 = SERVICE_IBLUETOOTHGATT;
} else {
Log.e(TAG, "Unknown service connected: " + className.getClassName());
return;
}
msg.obj = service;
mHandler.sendMessage(msg);
} case MESSAGE_BLUETOOTH_SERVICE_CONNECTED:
{
if (DBG) Log.d(TAG,"MESSAGE_BLUETOOTH_SERVICE_CONNECTED: " + msg.arg1);
IBinder service = (IBinder) msg.obj;
synchronized(mConnection) {
if (msg.arg1 == SERVICE_IBLUETOOTHGATT) {
mBluetoothGatt = IBluetoothGatt.Stub.asInterface(service);
onBluetoothGattServiceUp();
break;
} // else must be SERVICE_IBLUETOOTH
//Remove timeout
mHandler.removeMessages(MESSAGE_TIMEOUT_BIND);
mBinding = false;
mBluetooth = IBluetooth.Stub.asInterface(service);
try {
boolean enableHciSnoopLog = (Settings.Secure.getInt(mContentResolver,
Settings.Secure.BLUETOOTH_HCI_LOG, 0) == 1);
if (!mBluetooth.configHciSnoopLog(enableHciSnoopLog)) {
Log.e(TAG,"IBluetooth.configHciSnoopLog return false");
}
} catch (RemoteException e) {
Log.e(TAG,"Unable to call configHciSnoopLog", e);
}
if (mConnection.isGetNameAddressOnly()) {
//Request GET NAME AND ADDRESS
Message getMsg = mHandler.obtainMessage(MESSAGE_GET_NAME_AND_ADDRESS);
mHandler.sendMessage(getMsg);
if (!mEnable) return;
}
mConnection.setGetNameAddressOnly(false);
//Register callback object
try {
mBluetooth.registerCallback(mBluetoothCallback);
} catch (RemoteException re) {
Log.e(TAG, "Unable to register BluetoothCallback",re);
}
//Inform BluetoothAdapter instances that service is up
sendBluetoothServiceUpCallback();
//Do enable request
try {
if (mQuietEnable == false) {
if(!mBluetooth.enable()) {
Log.e(TAG,"IBluetooth.enable() returned false");
}
}
else
{
if(!mBluetooth.enableNoAutoConnect()) {
Log.e(TAG,"IBluetooth.enableNoAutoConnect() returned false");
}
}
} catch (RemoteException e) {
Log.e(TAG,"Unable to call enable()",e);
}
}
if (!mEnable) {
waitForOnOff(true, false);
handleDisable();
waitForOnOff(false, false);
}
break;
}在AdapterService的onBind会返回AdapterServiceBinder，看下AdapterServiceBinder
public boolean enable() {
if ((Binder.getCallingUid() != Process.SYSTEM_UID) &&
(!Utils.checkCaller())) {
Log.w(TAG, "enable() - Not allowed for non-active user and non system user");
return false;
}
AdapterService service = getService();
if (service == null) return false;
return service.enable();
}AdapterService
public synchronized boolean enable(boolean quietMode) {
enforceCallingOrSelfPermission(BLUETOOTH_ADMIN_PERM, "Need BLUETOOTH ADMIN permission");
debugLog("enable() - Enable called with quiet mode status = " + mQuietmode);
mQuietmode = quietMode;
Message m = mAdapterStateMachine.obtainMessage(AdapterState.BLE_TURN_ON);
mAdapterStateMachine.sendMessage(m);
return true;
} switch(msg.what) {
case BLE_TURN_ON:
notifyAdapterStateChange(BluetoothAdapter.STATE_BLE_TURNING_ON);
mPendingCommandState.setBleTurningOn(true);
transitionTo(mPendingCommandState);
sendMessageDelayed(BLE_START_TIMEOUT, BLE_START_TIMEOUT_DELAY);
adapterService.BleOnProcessStart();
break;AdapterService.java
void BleOnProcessStart() {
debugLog("BleOnProcessStart()");
Class[] supportedProfileServices = Config.getSupportedProfiles();
//Initialize data objects
debugLog("supportedProfileServices.length = " + supportedProfileServices.length);
for (int i=0; i < supportedProfileServices.length;i++) {
debugLog("supportedProfileServices[" + i + "]: " + supportedProfileServices[i].getName());
mProfileServicesState.put(supportedProfileServices[i].getName(),BluetoothAdapter.STATE_OFF);
}
mRemoteDevices = new RemoteDevices(this);
mAdapterProperties.init(mRemoteDevices);
debugLog("BleOnProcessStart() - Make Bond State Machine");
mBondStateMachine = BondStateMachine.make(this, mAdapterProperties, mRemoteDevices);
mJniCallbacks.init(mBondStateMachine,mRemoteDevices);
//FIXME: Set static instance here???
setAdapterService(this);
//Start Gatt service
setGattProfileServiceState(supportedProfileServices,BluetoothAdapter.STATE_ON);
}config.xml
true
false
true
true
false
true
true
true
true
true
false
true
true
false
false AdapterService.java
private void setGattProfileServiceState(Class[] services, int state) {
if (state != BluetoothAdapter.STATE_ON && state != BluetoothAdapter.STATE_OFF) {
Log.w(TAG,"setGattProfileServiceState(): invalid state...Leaving...");
return;
}
int expectedCurrentState= BluetoothAdapter.STATE_OFF;
int pendingState = BluetoothAdapter.STATE_TURNING_ON;
if (state == BluetoothAdapter.STATE_OFF) {
expectedCurrentState= BluetoothAdapter.STATE_ON;
pendingState = BluetoothAdapter.STATE_TURNING_OFF;
}
for (int i=0; i 调用了notifyProfileServiceStateChanged(BluetoothAdapter.STATE_ON);
protected void notifyProfileServiceStateChanged(int state) {
//Notify adapter service
if (mAdapterService != null) {
mAdapterService.onProfileServiceStateChanged(getClass().getName(), state);
}
}AdapterService.java
public void onProfileServiceStateChanged(String serviceName, int state) {
Message m = mHandler.obtainMessage(MESSAGE_PROFILE_SERVICE_STATE_CHANGED);
m.obj=serviceName;
m.arg1 = state;
mHandler.sendMessage(m);
} switch (msg.what) {
case MESSAGE_PROFILE_SERVICE_STATE_CHANGED: {
debugLog("handleMessage() - MESSAGE_PROFILE_SERVICE_STATE_CHANGED");
processProfileServiceStateChanged((String) msg.obj, msg.arg1);
}
break; private void processProfileServiceStateChanged(String serviceName, int state) {
...
if (isBleTurningOn) {
if (serviceName.equals("com.android.bluetooth.gatt.GattService")) {
debugLog("GattService is started");
mAdapterStateMachine.sendMessage(mAdapterStateMachine.obtainMessage(AdapterState.BLE_STARTED));
return;
}
} case BLE_STARTED:
//Remove start timeout
removeMessages(BLE_START_TIMEOUT);
//Enable
boolean isGuest = UserManager.get(mAdapterService).isGuestUser();
if (!adapterService.enableNative(isGuest)) {
errorLog("Error while turning Bluetooth on");
notifyAdapterStateChange(BluetoothAdapter.STATE_OFF);
transitionTo(mOffState);
} else {
sendMessageDelayed(ENABLE_TIMEOUT, ENABLE_TIMEOUT_DELAY);
}
break;static jboolean enableNative(JNIEnv* env, jobject obj, jboolean isGuest) {
ALOGV("%s:",__FUNCTION__);
jboolean result = JNI_FALSE;
if (!sBluetoothInterface) return result;
int ret = sBluetoothInterface->enable(isGuest == JNI_TRUE ? 1 : 0);
result = (ret == BT_STATUS_SUCCESS || ret == BT_STATUS_DONE) ? JNI_TRUE : JNI_FALSE;
return result;
}调用了sBluetoothInterface->enable，这个 sBluetoothInterface在classInitNative中初始化了
static void classInitNative(JNIEnv* env, jclass clazz) {
int err;
hw_module_t* module;
...
char value[PROPERTY_VALUE_MAX];
property_get("bluetooth.mock_stack", value, "");
const char *id = (strcmp(value, "1")? BT_STACK_MODULE_ID : BT_STACK_TEST_MODULE_ID);
err = hw_get_module(id, (hw_module_t const**)&module);
if (err == 0) {
hw_device_t* abstraction;
err = module->methods->open(module, id, &abstraction);
if (err == 0) {
bluetooth_module_t* btStack = (bluetooth_module_t *)abstraction;
sBluetoothInterface = btStack->get_bluetooth_interface();
} else {
ALOGE("Error while opening Bluetooth library");
}
} else {
ALOGE("No Bluetooth Library found");
}
int hw_get_module(const char *id, const struct hw_module_t **module)
{
return hw_get_module_by_class(id, NULL, module);
}static int hw_module_exists(char *path, size_t path_len, const char *name,
const char *subname)
{
...
return load(class_id, path, module);
}static int load(const char *id,
const char *path,
const struct hw_module_t **pHmi)
{
int status = -EINVAL;
void *handle = NULL;
struct hw_module_t *hmi = NULL;
/*
* load the symbols resolving undefined symbols before
* dlopen returns. Since RTLD_GLOBAL is not or'd in with
* RTLD_NOW the external symbols will not be global
*/
handle = dlopen(path, RTLD_NOW);
if (handle == NULL) {
char const *err_str = dlerror();
ALOGE("load: module=%s\n%s", path, err_str?err_str:"unknown");
status = -EINVAL;
goto done;
}
/* Get the address of the struct hal_module_info. */
const char *sym = HAL_MODULE_INFO_SYM_AS_STR;
hmi = (struct hw_module_t *)dlsym(handle, sym);
if (hmi == NULL) {
ALOGE("load: couldn't find symbol %s", sym);
status = -EINVAL;
goto done;
}
/* Check that the id matches */
if (strcmp(id, hmi->id) != 0) {
ALOGE("load: id=%s != hmi->id=%s", id, hmi->id);
status = -EINVAL;
goto done;
}
hmi->dso = handle;
/* success */
status = 0;
done:
if (status != 0) {
hmi = NULL;
if (handle != NULL) {
dlclose(handle);
handle = NULL;
}
} else {
ALOGV("loaded HAL id=%s path=%s hmi=%p handle=%p",
id, path, *pHmi, handle);
}
*pHmi = hmi;
return status;
}至于BT_STACK_MODULE_ID，在hardware/libhardware/include/hardware/Bluetooth.h中定义了
#define BT_STACK_MODULE_ID "bluetooth"
看下system/bt/btif/src/Bluetooth.c，果然找到相关方法
const bt_interface_t* bluetooth__get_bluetooth_interface ()
{
/* fixme -- add property to disable bt interface ? */
return &bluetoothInterface;
}static const bt_interface_t bluetoothInterface = {
sizeof(bluetoothInterface),
init,
enable,
disable,
cleanup,
get_adapter_properties,
get_adapter_property,
set_adapter_property,
get_remote_device_properties,
get_remote_device_property,
set_remote_device_property,
get_remote_service_record,
get_remote_services,
start_discovery,
cancel_discovery,
create_bond,
remove_bond,
cancel_bond,
get_connection_state,
pin_reply,
ssp_reply,
get_profile_interface,
dut_mode_configure,
dut_mode_send,
#if BLE_INCLUDED == TRUE
le_test_mode,
#else
NULL,
#endif
config_hci_snoop_log,
set_os_callouts,
read_energy_info,
dump,
config_clear
};
static int enable(bool start_restricted) {
LOG_INFO(LOG_TAG, "%s: start restricted = %d", __func__, start_restricted);
restricted_mode = start_restricted;
if (!interface_ready())
return BT_STATUS_NOT_READY;
stack_manager_get_interface()->start_up_stack_async();
return BT_STATUS_SUCCESS;
}stack_manager_get_interface在stack_manager.c中
const stack_manager_t *stack_manager_get_interface() {
ensure_manager_initialized();
return &interface;
}
static const stack_manager_t interface = {
init_stack,
start_up_stack_async,
shut_down_stack_async,
clean_up_stack_async,
get_stack_is_running
};
static void start_up_stack_async(void) {
thread_post(management_thread, event_start_up_stack, NULL);
}static void event_start_up_stack(UNUSED_ATTR void *context) {
if (stack_is_running) {
LOG_DEBUG("%s stack already brought up.", __func__);
return;
}
ensure_stack_is_initialized();
LOG_DEBUG("%s is bringing up the stack.", __func__);
hack_future = future_new();
// Include this for now to put btif config into a shutdown-able state
module_start_up(get_module(BTIF_CONFIG_MODULE));
bte_main_enable();
if (future_await(hack_future) != FUTURE_SUCCESS) {
stack_is_running = true; // So stack shutdown actually happens
event_shut_down_stack(NULL);
return; } stack_is_running = true; LOG_DEBUG("%s finished", __func__); btif_thread_post(event_signal_stack_up, NULL);}void bte_main_enable()
{
APPL_TRACE_DEBUG("%s", __FUNCTION__);
module_start_up(get_module(BTSNOOP_MODULE));
module_start_up(get_module(HCI_MODULE));
BTU_StartUp();
}void BTU_StartUp(void)
{
memset (&btu_cb, 0, sizeof (tBTU_CB));
btu_cb.trace_level = HCI_INITIAL_TRACE_LEVEL;
btu_bta_msg_queue = fixed_queue_new(SIZE_MAX);
if (btu_bta_msg_queue == NULL)
goto error_exit;
btu_general_alarm_hash_map = hash_map_new(BTU_GENERAL_ALARM_HASH_MAP_SIZE,
hash_function_pointer, NULL, (data_free_fn)alarm_free, NULL);
if (btu_general_alarm_hash_map == NULL)
goto error_exit;
if (pthread_mutex_init(&btu_general_alarm_lock, NULL))
goto error_exit;
btu_general_alarm_queue = fixed_queue_new(SIZE_MAX);
if (btu_general_alarm_queue == NULL)
goto error_exit;
btu_oneshot_alarm_hash_map = hash_map_new(BTU_ONESHOT_ALARM_HASH_MAP_SIZE,
hash_function_pointer, NULL, (data_free_fn)alarm_free, NULL);
if (btu_oneshot_alarm_hash_map == NULL)
goto error_exit;
if (pthread_mutex_init(&btu_oneshot_alarm_lock, NULL))
goto error_exit;
btu_oneshot_alarm_queue = fixed_queue_new(SIZE_MAX);
if (btu_oneshot_alarm_queue == NULL)
goto error_exit;
btu_l2cap_alarm_hash_map = hash_map_new(BTU_L2CAP_ALARM_HASH_MAP_SIZE,
hash_function_pointer, NULL, (data_free_fn)alarm_free, NULL);
if (btu_l2cap_alarm_hash_map == NULL)
goto error_exit;
if (pthread_mutex_init(&btu_l2cap_alarm_lock, NULL))
goto error_exit;
btu_l2cap_alarm_queue = fixed_queue_new(SIZE_MAX);
if (btu_l2cap_alarm_queue == NULL)
goto error_exit;
bt_workqueue_thread = thread_new(BT_WORKQUEUE_NAME);
if (bt_workqueue_thread == NULL)
goto error_exit;
// Continue startup on bt workqueue thread.
thread_post(bt_workqueue_thread, btu_task_start_up, NULL);
return;
error_exit:;
LOG_ERROR("%s Unable to allocate resources for bt_workqueue", __func__);
BTU_ShutDown();
}Btu_task.c
void btu_task_start_up(UNUSED_ATTR void *context) {
BT_TRACE(TRACE_LAYER_BTU, TRACE_TYPE_API,
"btu_task pending for preload complete event");
LOG_INFO("Bluetooth chip preload is complete");
BT_TRACE(TRACE_LAYER_BTU, TRACE_TYPE_API,
"btu_task received preload complete event");
/* Initialize the mandatory core stack control blocks
(BTU, BTM, L2CAP, and SDP)
*/
btu_init_core();
/* Initialize any optional stack components */
BTE_InitStack();
bta_sys_init();
/* Initialise platform trace levels at this point as BTE_InitStack() and bta_sys_init()
* reset the control blocks and preset the trace level with XXX_INITIAL_TRACE_LEVEL
*/
#if ( BT_USE_TRACES==TRUE )
module_init(get_module(BTE_LOGMSG_MODULE));
#endif
// Inform the bt jni thread initialization is ok.
btif_transfer_context(btif_init_ok, 0, NULL, 0, NULL);
fixed_queue_register_dequeue(btu_bta_msg_queue,
thread_get_reactor(bt_workqueue_thread),
btu_bta_msg_ready,
NULL);
fixed_queue_register_dequeue(btu_hci_msg_queue,
thread_get_reactor(bt_workqueue_thread),
btu_hci_msg_ready,
NULL);
fixed_queue_register_dequeue(btu_general_alarm_queue,
thread_get_reactor(bt_workqueue_thread),
btu_general_alarm_ready,
NULL);
fixed_queue_register_dequeue(btu_oneshot_alarm_queue,
thread_get_reactor(bt_workqueue_thread),
btu_oneshot_alarm_ready,
NULL);
fixed_queue_register_dequeue(btu_l2cap_alarm_queue,
thread_get_reactor(bt_workqueue_thread),
btu_l2cap_alarm_ready,
NULL);
}Btif_core.c
void btif_init_ok(UNUSED_ATTR uint16_t event, UNUSED_ATTR char *p_param) {
BTIF_TRACE_DEBUG("btif_task: received trigger stack init event");
#if (BLE_INCLUDED == TRUE)
btif_dm_load_ble_local_keys();
#endif
BTA_EnableBluetooth(bte_dm_evt);
}system/bt/bta/dm/Bta_dm_api.c
tBTA_STATUS BTA_EnableBluetooth(tBTA_DM_SEC_CBACK *p_cback)
{
tBTA_DM_API_ENABLE *p_msg;
/* Bluetooth disabling is in progress */
if (bta_dm_cb.disabling)
return BTA_FAILURE;
memset(&bta_dm_cb, 0, sizeof(bta_dm_cb));
bta_sys_register (BTA_ID_DM, &bta_dm_reg );
bta_sys_register (BTA_ID_DM_SEARCH, &bta_dm_search_reg );
/* if UUID list is not provided as static data */
bta_sys_eir_register(bta_dm_eir_update_uuid);
if ((p_msg = (tBTA_DM_API_ENABLE *) GKI_getbuf(sizeof(tBTA_DM_API_ENABLE))) != NULL)
{
p_msg->hdr.event = BTA_DM_API_ENABLE_EVT;
p_msg->p_sec_cback = p_cback;
bta_sys_sendmsg(p_msg);
return BTA_SUCCESS;
}
return BTA_FAILURE;
}这里看看这个BTA_DM_API_ENABLE_EVT是什么，首先看看Bta_dm_int.h声明了一组枚举类型enum
{
/* device manager local device API events */
BTA_DM_API_ENABLE_EVT = BTA_SYS_EVT_START(BTA_ID_DM),
BTA_DM_API_DISABLE_EVT,
这个BTA_SYS_EVT_START又是什么？通过搜索在Bta_sys.h中找到了这个宏，这里先标志一下#define BTA_SYS_EVT_START(id) ((id) << 8)
system/bt/gki/common/Gki_buffer.c
void *GKI_getbuf (UINT16 size)
{
BUFFER_HDR_T *header = osi_malloc(size + BUFFER_HDR_SIZE);
header->status = BUF_STATUS_UNLINKED;
header->p_next = NULL;
header->Type = 0;
header->size = size;
return header + 1;
}system/bt/bta/sys/Bta_sys_main.c
void bta_sys_sendmsg(void *p_msg)
{
// There is a race condition that occurs if the stack is shut down while
// there is a procedure in progress that can schedule a task via this
// message queue. This causes |btu_bta_msg_queue| to get cleaned up before
// it gets used here; hence we check for NULL before using it.
if (btu_bta_msg_queue)
fixed_queue_enqueue(btu_bta_msg_queue, p_msg);
}system/bt/stack/btu/Btu_init.c
void BTU_StartUp(void)
{
memset (&btu_cb, 0, sizeof (tBTU_CB));
btu_cb.trace_level = HCI_INITIAL_TRACE_LEVEL;
btu_bta_msg_queue = fixed_queue_new(SIZE_MAX);
if (btu_bta_msg_queue == NULL)
goto error_exit;
......system/bt/stack/btu/Btu_task.c
void btu_task_start_up(UNUSED_ATTR void *context) {
......
fixed_queue_register_dequeue(btu_bta_msg_queue,
thread_get_reactor(bt_workqueue_thread),
btu_bta_msg_ready,
NULL);
void btu_bta_msg_ready(fixed_queue_t *queue, UNUSED_ATTR void *context) {
BT_HDR *p_msg = (BT_HDR *)fixed_queue_dequeue(queue);
bta_sys_event(p_msg);
}system/bt/bta/sys/Bta_sys_main.c
void bta_sys_event(BT_HDR *p_msg)
{
UINT8 id;
BOOLEAN freebuf = TRUE;
APPL_TRACE_EVENT("BTA got event 0x%x", p_msg->event);
/* get subsystem id from event */
id = (UINT8) (p_msg->event >> 8);
/* verify id and call subsystem event handler */
if ((id < BTA_ID_MAX) && (bta_sys_cb.reg[id] != NULL))
{
freebuf = (*bta_sys_cb.reg[id]->evt_hdlr)(p_msg);
}
else
{
APPL_TRACE_WARNING("BTA got unregistered event id %d", id);
}
if (freebuf)
{
GKI_freebuf(p_msg);
}
}关键在于freebuf = (*bta_sys_cb.reg[id]->evt_hdlr)(p_msg);这个reg的赋值在
void bta_sys_register(UINT8 id, const tBTA_SYS_REG *p_reg)
{
bta_sys_cb.reg[id] = (tBTA_SYS_REG *) p_reg;
bta_sys_cb.is_reg[id] = TRUE;
}搜索bta_sys_register (BTA_ID_DM发现是在Bta_dm_api.c有调用
tBTA_STATUS BTA_EnableBluetooth(tBTA_DM_SEC_CBACK *p_cback)
{
tBTA_DM_API_ENABLE *p_msg;
/* Bluetooth disabling is in progress */
if (bta_dm_cb.disabling)
return BTA_FAILURE;
memset(&bta_dm_cb, 0, sizeof(bta_dm_cb));
bta_sys_register (BTA_ID_DM, &bta_dm_reg );
bta_sys_register (BTA_ID_DM_SEARCH, &bta_dm_search_reg );
/* if UUID list is not provided as static data */
bta_sys_eir_register(bta_dm_eir_update_uuid);
if ((p_msg = (tBTA_DM_API_ENABLE *) GKI_getbuf(sizeof(tBTA_DM_API_ENABLE))) != NULL)
{
p_msg->hdr.event = BTA_DM_API_ENABLE_EVT;
p_msg->p_sec_cback = p_cback;
bta_sys_sendmsg(p_msg);
return BTA_SUCCESS;
}
return BTA_FAILURE;static const tBTA_SYS_REG bta_dm_reg =
{
bta_dm_sm_execute,
bta_dm_sm_disable
};
system/bt/bta/dm/Bta_dm_main.c
BOOLEAN bta_dm_sm_execute(BT_HDR *p_msg)
{
UINT16 event = p_msg->event & 0x00ff;
APPL_TRACE_EVENT("bta_dm_sm_execute event:0x%x", event);
/* execute action functions */
if(event < BTA_DM_NUM_ACTIONS)
{
(*bta_dm_action[event])( (tBTA_DM_MSG*) p_msg);
}
return TRUE;
}还记得吗，event=1<<8也就是256，化成二进制就是100000000（1和八个零），而0x00ff是011111111（0和八个一），两个&运算等于0，bta_dm_action的定义也在这个文件中
/* action function list */
const tBTA_DM_ACTION bta_dm_action[] =
{
/* device manager local device API events */
bta_dm_enable, /* 0 BTA_DM_API_ENABLE_EVT */
bta_dm_disable, /* 1 BTA_DM_API_DISABLE_EVT */
bta_dm_set_dev_name, /* 2 BTA_DM_API_SET_NAME_EVT */
bta_dm_set_visibility, /* 3 BTA_DM_API_SET_VISIBILITY_EVT */
bta_dm_acl_change, /* 8 BTA_DM_ACL_CHANGE_EVT */
bta_dm_add_device, /* 9 BTA_DM_API_ADD_DEVICE_EVT */
bta_dm_close_acl, /* 10 BTA_DM_API_ADD_DEVICE_EVT */
/* security API events */
bta_dm_bond, /* 11 BTA_DM_API_BOND_EVT */
bta_dm_bond_cancel, /* 12 BTA_DM_API_BOND_CANCEL_EVT */
bta_dm_pin_reply, /* 13 BTA_DM_API_PIN_REPLY_EVT */bta_dm_enable的实现在Bta_dm_act中
void bta_dm_enable(tBTA_DM_MSG *p_data)
{
tBTA_SYS_HW_MSG *sys_enable_event;
tBTA_DM_ENABLE enable_event;
/* if already in use, return an error */
if( bta_dm_cb.is_bta_dm_active == TRUE )
{
APPL_TRACE_WARNING("%s Device already started by another application", __func__);
memset(&enable_event, 0, sizeof(tBTA_DM_ENABLE));
enable_event.status = BTA_FAILURE;
if (p_data->enable.p_sec_cback != NULL)
p_data->enable.p_sec_cback(BTA_DM_ENABLE_EVT, (tBTA_DM_SEC *)&enable_event);
return;
}
/* first, register our callback to SYS HW manager */
bta_sys_hw_register( BTA_SYS_HW_BLUETOOTH, bta_dm_sys_hw_cback );
/* make sure security callback is saved - if no callback, do not erase the previous one,
it could be an error recovery mechanism */
if( p_data->enable.p_sec_cback != NULL )
bta_dm_cb.p_sec_cback = p_data->enable.p_sec_cback;
/* notify BTA DM is now active */
bta_dm_cb.is_bta_dm_active = TRUE;
/* send a message to BTA SYS */
if ((sys_enable_event = (tBTA_SYS_HW_MSG *) GKI_getbuf(sizeof(tBTA_SYS_HW_MSG))) != NULL)
{
sys_enable_event->hdr.event = BTA_SYS_API_ENABLE_EVT;
sys_enable_event->hw_module = BTA_SYS_HW_BLUETOOTH;
bta_sys_sendmsg(sys_enable_event);
}
} /* first, register our callback to SYS HW manager */
bta_sys_hw_register( BTA_SYS_HW_BLUETOOTH, bta_dm_sys_hw_cback );
/* make sure security callback is saved - if no callback, do not erase the previous one,
it could be an error recovery mechanism */
if( p_data->enable.p_sec_cback != NULL )
bta_dm_cb.p_sec_cback = p_data->enable.p_sec_cback;-_-！这不就两个注册回调函数吗！？我们再回头看看
看来 bta_sys_sendmsg(sys_enable_event)才是处理，这个和之前分析的一样，我们只要找到BTA_SYS_API_ENABLE_EVT的值，再找到对应的注册，就可以知道在哪处理的了
enum
{
/* device manager local device API events */
BTA_SYS_API_ENABLE_EVT = BTA_SYS_EVT_START(BTA_ID_SYS),
BTA_SYS_EVT_ENABLED_EVT,
BTA_SYS_EVT_STACK_ENABLED_EVT,
BTA_SYS_API_DISABLE_EVT,
BTA_SYS_EVT_DISABLED_EVT,
BTA_SYS_ERROR_EVT,
BTA_SYS_MAX_EVT
};void bta_sys_init(void)
{
memset(&bta_sys_cb, 0, sizeof(tBTA_SYS_CB));
pthread_mutex_init(&bta_alarm_lock, NULL);
bta_alarm_hash_map = hash_map_new(BTA_ALARM_HASH_MAP_SIZE,
hash_function_pointer, NULL, (data_free_fn)alarm_free, NULL);
btu_bta_alarm_queue = fixed_queue_new(SIZE_MAX);
fixed_queue_register_dequeue(btu_bta_alarm_queue,
thread_get_reactor(bt_workqueue_thread),
btu_bta_alarm_ready,
NULL);
appl_trace_level = APPL_INITIAL_TRACE_LEVEL;
/* register BTA SYS message handler */
bta_sys_register( BTA_ID_SYS, &bta_sys_hw_reg);
/* register for BTM notifications */
BTM_RegisterForDeviceStatusNotif ((tBTM_DEV_STATUS_CB*)&bta_sys_hw_btm_cback );
#if( defined BTA_AR_INCLUDED ) && (BTA_AR_INCLUDED == TRUE)
bta_ar_init();
#endif
}
static const tBTA_SYS_REG bta_sys_hw_reg =
{
bta_sys_sm_execute,
NULL
};
BOOLEAN bta_sys_sm_execute(BT_HDR *p_msg)
{
BOOLEAN freebuf = TRUE;
tBTA_SYS_ST_TBL state_table;
UINT8 action;
int i;
APPL_TRACE_EVENT("bta_sys_sm_execute state:%d, event:0x%x", bta_sys_cb.state, p_msg->event);
/* look up the state table for the current state */
state_table = bta_sys_st_tbl[bta_sys_cb.state];
/* update state */
bta_sys_cb.state = state_table[p_msg->event & 0x00ff][BTA_SYS_NEXT_STATE];
/* execute action functions */
for (i = 0; i < BTA_SYS_ACTIONS; i++)
{
if ((action = state_table[p_msg->event & 0x00ff][i]) != BTA_SYS_IGNORE)
{
(*bta_sys_action[action])( (tBTA_SYS_HW_MSG*) p_msg);
}
else
{
break;
}
}
return freebuf;
}
这里是状态模式了，状态模式的特点是不同状态响应命令有不同操作。首先BTA_ID_SYS=0，所以BTA_SYS_API_ENABLE_EVT=0<<8=0;
bta_sys_cb.state=bta_sys_hw_off，所以state_table = bta_sys_st_tbl[bta_sys_cb.state]
--》state_table =
const UINT8 bta_sys_hw_off[][BTA_SYS_NUM_COLS] =
{
/* Event Action 1 Action 2 Next State */
/* API_ENABLE */ {BTA_SYS_HW_API_ENABLE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING},
/* EVT_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING},
/* STACK_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* API_DISABLE */ {BTA_SYS_HW_EVT_DISABLED, BTA_SYS_IGNORE, BTA_SYS_HW_OFF},
/* EVT_DISABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_OFF},
/* EVT_ERROR */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_OFF}
};
bta_sys_cb.state = state_table[p_msg->event & 0x00ff][BTA_SYS_NEXT_STATE]——》bta_sys_cb.state =BTA_SYS_HW_STARTING，下个状态是starting,进入循环，state_table【0】【0】=BTA_SYS_HW_API_ENABLE（下一次循环就break了），所以执行bta_sys_hw_api_enable
附：
/* state table */
const tBTA_SYS_ST_TBL bta_sys_st_tbl[] = {
bta_sys_hw_off,
bta_sys_hw_starting,
bta_sys_hw_on,
bta_sys_hw_stopping
};/* state table for OFF state */
const UINT8 bta_sys_hw_off[][BTA_SYS_NUM_COLS] =
{
/* Event Action 1 Action 2 Next State */
/* API_ENABLE */ {BTA_SYS_HW_API_ENABLE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING},
/* EVT_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING},
/* STACK_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* API_DISABLE */ {BTA_SYS_HW_EVT_DISABLED, BTA_SYS_IGNORE, BTA_SYS_HW_OFF},
/* EVT_DISABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_OFF},
/* EVT_ERROR */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_OFF}
};
const UINT8 bta_sys_hw_starting[][BTA_SYS_NUM_COLS] =
{
/* Event Action 1 Action 2 Next State */
/* API_ENABLE */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING}, /* wait for completion event */
/* EVT_ENABLED */ {BTA_SYS_HW_EVT_ENABLED, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING},
/* STACK_ENABLED */ {BTA_SYS_HW_EVT_STACK_ENABLED, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* API_DISABLE */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STOPPING}, /* successive disable/enable: change state wait for completion to disable */
/* EVT_DISABLED */ {BTA_SYS_HW_EVT_DISABLED, BTA_SYS_HW_API_ENABLE, BTA_SYS_HW_STARTING}, /* successive enable/disable: notify, then restart HW */
/* EVT_ERROR */ {BTA_SYS_HW_ERROR, BTA_SYS_IGNORE, BTA_SYS_HW_ON}
};
const UINT8 bta_sys_hw_on[][BTA_SYS_NUM_COLS] =
{
/* Event Action 1 Action 2 Next State */
/* API_ENABLE */ {BTA_SYS_HW_API_ENABLE, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* EVT_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* STACK_ENABLED */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* API_DISABLE */ {BTA_SYS_HW_API_DISABLE, BTA_SYS_IGNORE, BTA_SYS_HW_ON}, /* don't change the state here, as some other modules might be active */
/* EVT_DISABLED */ {BTA_SYS_HW_ERROR, BTA_SYS_IGNORE, BTA_SYS_HW_ON},
/* EVT_ERROR */ {BTA_SYS_HW_ERROR, BTA_SYS_IGNORE, BTA_SYS_HW_ON}
};
const UINT8 bta_sys_hw_stopping[][BTA_SYS_NUM_COLS] =
{
/* Event Action 1 Action 2 Next State */
/* API_ENABLE */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STARTING}, /* change state, and wait for completion event to enable */
/* EVT_ENABLED */ {BTA_SYS_HW_EVT_ENABLED, BTA_SYS_IGNORE, BTA_SYS_HW_STOPPING}, /* successive enable/disable: finish the enable before disabling */
/* STACK_ENABLED */ {BTA_SYS_HW_EVT_STACK_ENABLED, BTA_SYS_HW_API_DISABLE, BTA_SYS_HW_STOPPING}, /* successive enable/disable: notify, then stop */
/* API_DISABLE */ {BTA_SYS_IGNORE, BTA_SYS_IGNORE, BTA_SYS_HW_STOPPING}, /* wait for completion event */
/* EVT_DISABLED */ {BTA_SYS_HW_EVT_DISABLED, BTA_SYS_IGNORE, BTA_SYS_HW_OFF},
/* EVT_ERROR */ {BTA_SYS_HW_API_DISABLE, BTA_SYS_IGNORE, BTA_SYS_HW_STOPPING}
};
我们看下bta_sys_hw_api_enable方法
/*******************************************************************************
**
** Function bta_sys_hw_enable
**
** Description this function is called after API enable and HW has been turned on
**
**
** Returns success or failure
**
*******************************************************************************/
void bta_sys_hw_api_enable( tBTA_SYS_HW_MSG *p_sys_hw_msg )
{
if ((!bta_sys_cb.sys_hw_module_active) && (bta_sys_cb.state != BTA_SYS_HW_ON))
{
/* register which HW module was turned on */
bta_sys_cb.sys_hw_module_active |= ((UINT32)1 << p_sys_hw_msg->hw_module );
tBTA_SYS_HW_MSG *p_msg;
if ((p_msg = (tBTA_SYS_HW_MSG *) GKI_getbuf(sizeof(tBTA_SYS_HW_MSG))) != NULL)
{
p_msg->hdr.event = BTA_SYS_EVT_ENABLED_EVT;
p_msg->hw_module = p_sys_hw_msg->hw_module;
bta_sys_sendmsg(p_msg);
}
}
else
{
/* register which HW module was turned on */
bta_sys_cb.sys_hw_module_active |= ((UINT32)1 << p_sys_hw_msg->hw_module );
/* HW already in use, so directly notify the caller */
if (bta_sys_cb.sys_hw_cback[p_sys_hw_msg->hw_module ]!= NULL )
bta_sys_cb.sys_hw_cback[p_sys_hw_msg->hw_module ]( BTA_SYS_HW_ON_EVT );
}
APPL_TRACE_EVENT ("bta_sys_hw_api_enable for %d, active modules 0x%04X",
p_sys_hw_msg->hw_module, bta_sys_cb.sys_hw_module_active);
}网上查了很多，发现漏了一个很重要的地方，在bte_main.c的bte_main_enable()方法中，有句module_start_up(get_module(HCI_MODULE))，这个HCI_MODULE就是hci_layer.c,再看看module_start_up()方法，
bool module_start_up(const module_t *module) {
assert(metadata != NULL);
assert(module != NULL);
// TODO(zachoverflow): remove module->init check once automagic order/call is in place.
// This hack is here so modules which don't require init don't have to have useless calls
// as we're converting the startup sequence.
assert(get_module_state(module) == MODULE_STATE_INITIALIZED || module->init == NULL);
if (!call_lifecycle_function(module->start_up)) {
LOG_ERROR("%s failed to start up \"%s\"", __func__, module->name);
return false;
}
set_module_state(module, MODULE_STATE_STARTED);
return true;
}static future_t *start_up(void) {
......
packet_fragmenter->init(&packet_fragmenter_callbacks);
fixed_queue_register_dequeue(command_queue, thread_get_reactor(thread), event_command_ready, NULL);
fixed_queue_register_dequeue(packet_queue, thread_get_reactor(thread), event_packet_ready, NULL);
vendor->open(btif_local_bd_addr.address, &interface);
hal->init(&hal_callbacks, thread);
low_power_manager->init(thread);
vendor->set_callback(VENDOR_CONFIGURE_FIRMWARE, firmware_config_callback);
vendor->set_callback(VENDOR_CONFIGURE_SCO, sco_config_callback);
vendor->set_callback(VENDOR_DO_EPILOG, epilog_finished_callback);
if (!hci_inject->open(&interface)) {
// TODO(sharvil): gracefully propagate failures from this layer.
}
int power_state = BT_VND_PWR_OFF;
#if (defined (BT_CLEAN_TURN_ON_DISABLED) && BT_CLEAN_TURN_ON_DISABLED == TRUE)
LOG_WARN("%s not turning off the chip before turning on.", __func__);
// So apparently this hack was needed in the past because a Wingray kernel driver
// didn't handle power off commands in a powered off state correctly.
// The comment in the old code said the workaround should be removed when the
// problem was fixed. Sadly, I have no idea if said bug was fixed or if said
// kernel is still in use, so we must leave this here for posterity. #sadpanda
#else
// cycle power on the chip to ensure it has been reset
vendor->send_command(VENDOR_CHIP_POWER_CONTROL, &power_state);
#endif
power_state = BT_VND_PWR_ON;
vendor->send_command(VENDOR_CHIP_POWER_CONTROL, &power_state);
startup_future = future_new();
LOG_DEBUG("%s starting async portion", __func__);
thread_post(thread, event_finish_startup, NULL);
return startup_future;
error:;
shut_down(); // returns NULL so no need to wait for it
return future_new_immediate(FUTURE_FAIL);
}