开启User模式adb，取消授权，修改如下：
1、 /build/core/main.mk 修改以下内容
ifeq (true,$(strip $(enable_target_debugging)))
# Target is more debuggable and adbd is on by default
ADDITIONAL_DEFAULT_PROPERTIES += ro.debuggable=1
# Include the debugging/testing OTA keys in this build.
INCLUDE_TEST_OTA_KEYS := true
else # !enable_target_debugging
# Target is less debuggable and adbd is off by default
#把0改为1
ADDITIONAL_DEFAULT_PROPERTIES += ro.debuggable=0
endif # !enable_target_debugging
2，
frameworks/base/services/java/com/android/server/usb/UsbDeviceManager.java
修改以下内容：
public class UsbDeviceManager {
mUseUsbNotification = !massStorageSupported;
// make sure the ADB_ENABLED setting value matches the current state
Settings.Global.putInt(mContentResolver, Settings.Global.ADB_ENABLED, mAdbEnabled ? 1 : 0);
/* SPRD: reset the usb functions flag for usb function and SprdUsbSettings display @{ */
if (Settings.Global.getInt(mContentResolver,
将 mAdbEnabled ? 1 : 0 修改为 1，即
Settings.Global.putInt(mContentResolver, Settings.Global.ADB_ENABLED, 1);
开启User模式 Adb root权限，修改如下：
1，system/core/adb/Android.mk
修改以下内容：
LOCAL_SRC_FILES :=
LOCAL_CFLAGS := -O2 -g -DADB_HOST=0 -Wall -Wno-unused-parameter
LOCAL_CFLAGS += -D_XOPEN_SOURCE -D_GNU_SOURCE
ifneq (,$(filter user userdebug eng,$(TARGET_BUILD_VARIANT)))
LOCAL_CFLAGS += -DALLOW_ADBD_ROOT=1
endif
LOCAL_MODULE := adbd
将红色部分注释掉
2，/system/core/adb/adb.c
修改以下内容：
static void drop_capabilities_bounding_set_if_needed() {
static int should_drop_privileges() {
#ifndef ALLOW_ADBD_ROOT
return 1;
#else /* ALLOW_ADBD_ROOT */
int secure = 0;
char value[PROPERTY_VALUE_MAX];
@@ -1243,7 +1243,7 @@ static int should_drop_privileges() {
}
}
}
return secure;
#endif /* ALLOW_ADBD_ROOT */
}
#endif /* !ADB_HOST */
将 标红的部分修改为 return 0