|
蓝牙接收数据包流程
//底层数据包接收的源头 大约在此处
//再上去就是 监控 fd的守护进程了
void H4Protocol::OnDataReady( int fd ) ? ?
hci_packetizer_.OnDataReady(fd, hci_packet_type_);
void HciPacketizer::OnDataReady( int fd, HciPacketType packet_type )?
{
? ? //ALOGE( "HciPacketizer::OnDataReady state_ = %x", state_ );
?? ?
? ? switch (state_) {
? ? ? case HCI_PREAMBLE: {
? ? ? //ALOGE( "bytes_read_ = %x", bytes_read_ );
?? ??? ?
? ? ? ssize_t bytes_read = TEMP_FAILURE_RETRY(
? ? ? ? ? read(fd, preamble_ + bytes_read_,
? ? ? ? ? ? ? ?preamble_size_for_type[packet_type] - bytes_read_));
? ? ? if (bytes_read == 0) {
? ? ? ? // This is only expected if the UART got closed when shutting down.
? ? ? ? ALOGE("%s: Unexpected EOF reading the header!", __func__);
? ? ? ? sleep(5); ?// Expect to be shut down within 5 seconds.
? ? ? ? return;
? ? ? }
? ? ? if (bytes_read < 0) {
? ? ? ? LOG_ALWAYS_FATAL("%s: Read header error: %s", __func__,
? ? ? ? ? ? ? ? ? ? ? ? ?strerror(errno));
? ? ? }
?? ? ?//ALOGE( "bytes_read = %x", bytes_read );
? ? ? bytes_read_ += bytes_read;
?? ? ?//ALOGE( "bytes_read_ = %x", bytes_read_ );
? ? ? if (bytes_read_ == preamble_size_for_type[packet_type]) {
? ? ? ? size_t packet_length = HciGetPacketLengthForType(packet_type, preamble_);
? ? ? ? packet_.resize(preamble_size_for_type[packet_type] + packet_length);
? ? ? ? memcpy(packet_.data(), preamble_, preamble_size_for_type[packet_type]);
? ? ? ? bytes_remaining_ = packet_length;
? ? ? ? state_ = HCI_PAYLOAD;
? ? ? ? bytes_read_ = 0;
? ? ? }
? ? ? break;
? ? }
? ? case HCI_PAYLOAD: {
? ? ? ssize_t bytes_read = TEMP_FAILURE_RETRY(read(
? ? ? ? ? fd,
? ? ? ? ? packet_.data() + preamble_size_for_type[packet_type] + bytes_read_,
? ? ? ? ? bytes_remaining_));
? ? ? if (bytes_read == 0) {
? ? ? ? // This is only expected if the UART got closed when shutting down.
? ? ? ? ALOGE("%s: Unexpected EOF reading the payload!", __func__);
? ? ? ? sleep(5); ?// Expect to be shut down within 5 seconds.
? ? ? ? return;
? ? ? }
? ? ? if (bytes_read < 0) {
? ? ? ? LOG_ALWAYS_FATAL("%s: Read payload error: %s", __func__,
? ? ? ? ? ? ? ? ? ? ? ? ?strerror(errno));
? ? ? }
? ? ? bytes_remaining_ -= bytes_read;
? ? ? bytes_read_ += bytes_read;
? ? ? if (bytes_remaining_ == 0) {
?? ??? ?//output_buff((char*)packet_.data(), bytes_read_);
?? ??? ?ALOGE("get a packet data from uart" );
?? ??? ?macdbg_dmphex_kernel((const char*)packet_.data(), bytes_read_);
?? ??? ?//ALOGE("packet_ready_cb_.0 = %x", (unsigned int)&packet_ready_cb_ );
? ? ? ? packet_ready_cb_();
?? ??? ?//此处是关键 1
?? ??? ?//ALOGE("packet_ready_cb_.1 = %p", (void *)&packet_ready_cb_ );
? ? ? ? state_ = HCI_PREAMBLE;
? ? ? ? bytes_read_ = 0;
? ? ? }
? ? ? break;
? ? }
? }
}
//此处是关键 1 回调的就是这个函数
void H4Protocol::OnPacketReady()?
void H4Protocol::OnPacketReady()?
{
?? ?ALOGE("in %s", __func__);
?? ?//ALOGE("OnPacketReady.1 = %x", (unsigned int)(void (android::hardware::bluetooth::hci::H4Protocol::*)())(H4Protocol::OnPacketReady) );
?? ?
?? ?//android::CallStack ? ?stack;?? ??
?? ?//stack.update();?? ?
?? ?//stack.log("callstack");
?? ?ALOGE( "H4Protocol hci_packet_type_ = %x", hci_packet_type_ );
?? ? //bt_hci ?: hciEventReceived
? ? ?//07-09 16:30:41.408 ?2424 ?2775 I bt_hci ?: hci_event_received
? switch (hci_packet_type_) {
? ? case HCI_PACKET_TYPE_EVENT:
? ? ? event_cb_(hci_packetizer_.GetPacket());
?? ? ?//此处关键点2
? ? ? break;
? ? case HCI_PACKET_TYPE_ACL_DATA:
? ? ? acl_cb_(hci_packetizer_.GetPacket());
? ? ? break;
? ? case HCI_PACKET_TYPE_SCO_DATA:
? ? ? sco_cb_(hci_packetizer_.GetPacket());
? ? ? break;
? ? default:
#ifndef XRADIO_BLUETOOTH
? ? ? LOG_ALWAYS_FATAL("%s: Unimplemented packet type %d", __func__,
? ? ? ? ? ? ? ? ? ? ? ?static_cast<int>(hci_packet_type_));
#else
? ? ? break;
#endif
? }
??
??
??
Bluetooth_hci.cc
? bool rc = VendorInterface::Initialize(
? ? ? [cb](bool status) {
? ? ? ? auto hidl_status = cb->initializationComplete(
? ? ? ? ? ? status ? Status::SUCCESS : Status::INITIALIZATION_ERROR);
? ? ? ? if (!hidl_status.isOk()) {
? ? ? ? ? ALOGE("VendorInterface -> Unable to call initializationComplete()");
? ? ? ? }
? ? ? },
? ? ? [cb](const hidl_vec<uint8_t>& packet) {
? ? ? //此处关键点2 ? event_cb_
?? ? ?ALOGE("VendorInterface -> Unable to call hciEventReceived(1)");
? ? ? ? auto hidl_status = cb->hciEventReceived(packet);
?? ??? ?//此处关键点3 ??
?? ??? ?//由日志可以看出?
?? ??? ?bluetooth ? ? 1714 ? ? 1 ? 18292 ? 4616 0 ? ? ? ? ? ? ? ? ? 0 S android.hardware.bluetooth@1.0-service
?? ??? ?bluetooth ? ? 2430 ?1695 1435500 ?96972 0 ? ? ? ? ? ? ? ? ? 0 S com.android.bluetooth
?? ??? ?跨进程调用 从hal层 调用?
07-09 18:30:44.974 ?1714 ?2882 E android.hardware.bluetooth@1.0-impl: VendorInterface -> Unable to call hciEventReceived(1)
07-09 18:30:44.974 ?2430 ?2767 I bt_hci ?: hciEventReceived
07-09 18:30:44.974 ?2430 ?2767 E bt_hci ?: get a packet data from uartxxx
07-09 18:30:44.974 ?2430 ?2767 E bt_hci ?: data.size() = 6
07-09 18:30:44.974 ?2430 ?2767 E bt_hci ?: BT_HDR_SIZE = 8
07-09 18:30:44.975 ?2430 ?2767 E bt_hci ?: packet_size = e
07-09 18:30:44.975 ?2430 ?2767 E bt_hci ?: 0 ? ?0e 04 05 52 0c 00 ? ? ? ...R..
07-09 18:30:44.975 ?2430 ?2767 I bt_hci ?: hci_event_received
07-09 18:30:44.975 ?1714 ?2882 E android.hardware.bluetooth@1.0-impl: VendorInterface -> Unable to call hciEventReceived(2)
?? ??? ?ALOGE("VendorInterface -> Unable to call hciEventReceived(2)");
? ? ? ? if (!hidl_status.isOk()) {
? ? ? ? ? ALOGE("VendorInterface -> Unable to call hciEventReceived(3)");
? ? ? ? }
? ? ? },
? ? ? [cb](const hidl_vec<uint8_t>& packet) {
? ? ? ? auto hidl_status = cb->aclDataReceived(packet);
? ? ? ? if (!hidl_status.isOk()) {
? ? ? ? ? ALOGE("VendorInterface -> Unable to call aclDataReceived()");
? ? ? ? }
? ? ? },
? ? ? [cb](const hidl_vec<uint8_t>& packet) {
? ? ? ? auto hidl_status = cb->scoDataReceived(packet);
? ? ? ? if (!hidl_status.isOk()) {
? ? ? ? ? ALOGE("VendorInterface -> Unable to call scoDataReceived()");
? ? ? ? }
? ? ? });
?? ? ?
?? ? ?
//此处关键点3 ?
//Hci_layer_android.cc
?Return<void> hciEventReceived(const hidl_vec<uint8_t>& event) {
?? ?LOG_INFO(LOG_TAG, "%s", __func__);
?? ?
? ? BT_HDR* packet = WrapPacketAndCopy(MSG_HC_TO_STACK_HCI_EVT, event);
?? ?//构造数据包 packet
? ? hci_event_received(FROM_HERE, packet);
? ? return Void();
? }
??
//hci_layer.cc
void hci_event_received(const tracked_objects::Location& from_here,
? ? ? ? ? ? ? ? ? ? ? ? BT_HDR* packet) {
? btsnoop->capture(packet, true);
? LOG_INFO(LOG_TAG, "%s", __func__);
? if (!filter_incoming_event(packet)) {
? ? send_data_upwards.Run(from_here, packet);
? }
}
static void set_data_cb(
? ? base::Callback<void(const tracked_objects::Location&, BT_HDR*)>
? ? ? ? send_data_cb) {
? send_data_upwards = std::move(send_data_cb);
}
void bte_main_boot_entry(void) {
? module_init(get_module(INTEROP_MODULE));
? hci = hci_layer_get_interface();
? if (!hci) {
? ? LOG_ERROR(LOG_TAG, "%s could not get hci layer interface.", __func__);
? ? return;
? }
? hci->set_data_cb(base::Bind(&post_to_hci_message_loop));
? module_init(get_module(STACK_CONFIG_MODULE));
}
void post_to_hci_message_loop(const tracked_objects::Location& from_here,
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? BT_HDR* p_msg) {
? base::MessageLoop* hci_message_loop = get_message_loop();
? if (!hci_message_loop || !hci_message_loop->task_runner().get()) {
? ? LOG_ERROR(LOG_TAG, "%s: HCI message loop not running, accessed from %s",
? ? ? ? ? ? ? __func__, from_here.ToString().c_str());
? ? return;
? }
? hci_message_loop->task_runner()->PostTask(
? ? ? from_here, base::Bind(&btu_hci_msg_process, p_msg));
}
void btu_hci_msg_process( BT_HDR* p_msg ) ? ? ??
{
?? ?//LOG(INFO) << "btu_hci_msg_process";
?? ?//LOG(INFO) << "p_msg->event = "<< p_msg->event;
?? ?
? /* Determine the input message type. */
? switch (p_msg->event & BT_EVT_MASK) {
? ? case BT_EVT_TO_BTU_HCI_ACL:
? ? ? /* All Acl Data goes to L2CAP */
? ? ? l2c_rcv_acl_data(p_msg);
? ? ? break;
? ? case BT_EVT_TO_BTU_L2C_SEG_XMIT:
? ? ? /* L2CAP segment transmit complete */
? ? ? l2c_link_segments_xmitted(p_msg);
? ? ? break;
? ? case BT_EVT_TO_BTU_HCI_SCO:
#if (BTM_SCO_INCLUDED == TRUE)
? ? ? btm_route_sco_data(p_msg);
? ? ? break;
#endif
? ? case BT_EVT_TO_BTU_HCI_EVT:
? ? ? btu_hcif_process_event((uint8_t)(p_msg->event & BT_SUB_EVT_MASK), p_msg);
? ? ? osi_free(p_msg);
? ? ? break;
? ? case BT_EVT_TO_BTU_HCI_CMD:
? ? ? btu_hcif_send_cmd((uint8_t)(p_msg->event & BT_SUB_EVT_MASK), p_msg);
? ? ? break;
? ? default:
? ? ? osi_free(p_msg);
? ? ? break;
? }
}
大概意思如下:
串口上传数据包大概流程
由内核态的驱动程序 提供给 /dev/ttyS1 数据包,通过的是tty线路规程
发送一个信号通知用户态接收数据包
用户态进程监控 打开/dev/ttyS1的文件描述符fd
用户态解除阻塞等状态
就到了本文开头的位置
然后就是几个关键点的回调
一步步回调到蓝牙的协议栈里面去
具体细节还待分析
现在只是抓个主要脉络和框架
至于数据包的下发流程 基本是这个流程的逆过程
由hci接口 干到内核态去的
跟踪这个流程的关键是 用 macdbg_dmphex_kernel
打印各个节点的数据包的内容
以一个数据包的传递过程 来跟踪代码流程。
?
?
|