【Bluetooth】获取蓝牙地址的6种方法，及btnvtool工具使用

1.蓝牙地址获取android P：获取方法是bluetooth_address.cpp里面

vendor/qcom/proprietary/bluetooth/hidl_transport/bt/1.0/default/bluetooth_address.cpp

bool BluetoothAddress::GetLocalAddress(uint8_t *local_addr) { char property[PROPERTY_VALUE_MAX] = { 0 }; bool valid_bda = false; // Get addr from vendor location if (fetch_vendor_addr(local_addr)) { valid_bda = true; } // Get local bdaddr storage path from a system property. if (!valid_bda && property_get(PROPERTY_BT_BDADDR_PATH, property, NULL)) { int addr_fd; ALOGV("%s: Trying %s", __func__, property); addr_fd = open(property, O_RDONLY); if (addr_fd != -1) { int bytes_read = read(addr_fd, property, kStringLength); CHECK(bytes_read == kStringLength); close(addr_fd); // Null terminate the string. property[kStringLength] = '\0'; // If the address is not all zeros, then use it. const uint8_t zero_bdaddr[kBytes] = { 0, 0, 0, 0, 0, 0 }; if ((StringToBytes(property, local_addr)) && (memcmp(local_addr, zero_bdaddr, kBytes) != 0)) { valid_bda = true; le2bd(local_addr); ALOGD("%s: Got Factory BDA %s", __func__, property); } } } // No BDADDR found in the file. Look for BDA in a factory property. if (!valid_bda && property_get(FACTORY_BDADDR_PROPERTY, property, NULL) && StringToBytes(property, local_addr)) { valid_bda = true; le2bd(local_addr); } // Check if address is stored @ Modem NV if ((!valid_bda)&& property_get("persist.vendor.bluetooth.modem_nv_support", property, "false") && (strcmp(property, "true") == 0)) { ALOGV("%s: QMI initialization START ",__func__); if(!tried_reading_modemnv_) { int retry = 0; while (retry < QMI_INIT_MAX_TRY) { if (retry > 0) sleep(QMI_INIT_RETRY_INTERVAL_SEC); if (QmiDmsInit() == true) { if (QmiDmsGetAddress(modem_bdaddr_) == true) { char bdstr[kStringLength + 1]; ALOGE("Read MODEM_NV_BD_ADDR 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x \n", modem_bdaddr_[0], modem_bdaddr_[1], modem_bdaddr_[2], modem_bdaddr_[3], modem_bdaddr_[4], modem_bdaddr_[5]); valid_bda = true; read_addr_from_modemnv_ = true; memcpy(local_addr, modem_bdaddr_, kBytes); /* Convert to ascii, and store as a persistent property */ BytesToString(local_addr, bdstr); if (property_set(PERSIST_BDADDR_PROPERTY, (char*)bdstr) < 0) { ALOGE("%s: Failed to set MODEM_NV_BD_ADDR in prop %s", __func__, PERSIST_BDADDR_PROPERTY); } } QmiDmsCleanup(); break; } ++retry; ALOGE("%s: QMI initialization failed in %d try...", __func__, retry); } tried_reading_modemnv_ = true; } else if(read_addr_from_modemnv_) { memcpy(local_addr, modem_bdaddr_, kBytes); valid_bda = true; } } // No factory BDADDR found. Look for a previously stored BDA. if (!valid_bda && property_get(PERSIST_BDADDR_PROPERTY, property, NULL) && StringToBytes(property, local_addr)) { valid_bda = true; le2bd(local_addr); } /* Generate new BDA if necessary */ if (!valid_bda) { char bdstr[kStringLength + 1]; struct timespec cur_time; if (-1 == clock_gettime (CLOCK_MONOTONIC, &cur_time)) { ALOGE("%s: clock_gettime failed\n", __func__); } srand((unsigned int)cur_time.tv_nsec); /* No autogen BDA. Generate one now. */ local_addr[0] = 0x22; local_addr[1] = 0x22; local_addr[2] = (uint8_t)rand(); local_addr[3] = (uint8_t)rand(); local_addr[4] = (uint8_t)rand(); local_addr[5] = (uint8_t)rand(); /* Convert to ascii, and store as a persistent property */ BytesToString(local_addr, bdstr); ALOGE("%s: No preset BDA! Generating BDA: %s for prop %s", __func__, (char*)bdstr, PERSIST_BDADDR_PROPERTY); ALOGE("%s: This is a bug in the platform! Please fix!", __func__); if (property_set(PERSIST_BDADDR_PROPERTY, (char*)bdstr) < 0) { ALOGE("%s: Failed to set random BDA in prop %s", __func__, PERSIST_BDADDR_PROPERTY); valid_bda = false; } else { valid_bda = true; le2bd(local_addr); } } return valid_bda; }

在上面的代码中，一共有下面的 6 种获取mac地址的方法：

// Get addr from vendor location// Get local bdaddr storage path from a system property.// No BDADDR found in the file. Look for BDA in a factory property.// Check if address is stored @ Modem NV// No factory BDADDR found. Look for a previously stored BDA. /* Generate new BDA if necessary */

其中，当需要从NV去读取Bluetooth的mac地址时，代码走// Check if address is stored @ Modem NV里面；因为高通并没有在代码中做配置，所以需要我们去在device/qcom/common/common64.mk中添加persist.vendor.bluetooth.modem_nv_support=true \

diff --git a/common64.mk b/common64.mk--- a/common64.mk+++ b/common64.mk@@ -22,6 +22,7 @@ PRODUCT_PROPERTY_OVERRIDES += \ persist.vendor.radio.custom_ecc=1 \ persist.vendor.radio.rat_on=combine \ persist.backup.ntpServer=0.pool.ntp.org \+ persist.vendor.bluetooth.modem_nv_support=true \sys.vendor.shutdown.waittime=500 \

2.btnvtool工具adb rootadb shell向nv里写入mac地址：btnvtool -b 11.11.11.11.11.11 或者，btnvtool -b 22:22:22:22:22:22读nv的mac地址：btnvtool -p