通过下面命令行查看手机的event数据：
adb shell getevent -lp
找到ABS行，看后面ABS命令中有没有ABS_MT_SLOT，没有的话是TYPE_A,有的话是TYPE_B.
下面是抓取的手上几个手机（还有一个HUAWEI平板）的数据：
HUAWEI：TOUCH_TYPE_A(ok) ABS (0003): ABS_X : value 0, min 0, max 1439, fuzz 0, flat 0, resolution 0 ABS_Y : value 0, min 0, max 2559, fuzz 0, flat 0, resolution 0 ABS_PRESSURE : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_WIDTH_MAJOR : value 0, min 0, max 100, fuzz 0, flat 0, resolution 0 ABS_MT_WIDTH_MINOR : value 0, min 0, max 100, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_X : value 0, min 0, max 1439, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_Y : value 0, min 0, max 2559, fuzz 0, flat 0, resolution 0 ABS_MT_TRACKING_ID : value 0, min 0, max 15, fuzz 0, flat 0, resolution 0 ABS_MT_PRESSURE : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 MEIZU:TOUCH_TYPE_B(ok) ABS (0003): ABS_X : value 0, min 0, max 1080, fuzz 0, flat 0, resolution 1080 ABS_Y : value 0, min 0, max 1920, fuzz 0, flat 0, resolution 1920 ABS_PRESSURE : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_SLOT : value 0, min 0, max 9, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MAJOR : value 0, min 0, max 100, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MINOR : value 0, min 0, max 100, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_X : value 0, min 0, max 1080, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_Y : value 0, min 0, max 1920, fuzz 0, flat 0, resolution 0 ABS_MT_TRACKING_ID : value 0, min 0, max 10, fuzz 0, flat 0, resolution 0 ABS_MT_PRESSURE : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 XIAOMI:TOUCH_TYPE_B(ok) ABS (0003): ABS_MT_SLOT : value 0, min 0, max 9, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MAJOR : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_X : value 0, min 0, max 1079, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_Y : value 0, min 0, max 2279, fuzz 0, flat 0, resolution 0 ABS_MT_TRACKING_ID : value 0, min 0, max 65535, fuzz 0, flat 0, resolution 0 ABS_MT_PRESSURE : value 0, min 0, max 1000, fuzz 0, flat 0, resolution 0 JIANGUO:TOUCH_TYPE_B(ok) ABS (0003): ABS_X : value 0, min 0, max 1079, fuzz 0, flat 0, resolution 0 ABS_Y : value 0, min 0, max 2159, fuzz 0, flat 0, resolution 0 ABS_MT_SLOT : value 0, min 0, max 9, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MAJOR : value 0, min 0, max 27, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MINOR : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_X : value 0, min 0, max 1079, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_Y : value 0, min 0, max 2159, fuzz 0, flat 0, resolution 0 ABS_MT_TRACKING_ID : value 0, min 0, max 65535, fuzz 0, flat 0, resolution 0 HUAWEI PINGBAN:TOUCH_TYPE_B(ok) ABS (0003): ABS_MT_SLOT : value 0, min 0, max 31, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MAJOR : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_TOUCH_MINOR : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0 ABS_MT_ORIENTATION : value 0, min -297, max 127, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_X : value 0, min 0, max 1599, fuzz 0, flat 0, resolution 0 ABS_MT_POSITION_Y : value 0, min 0, max 2559, fuzz 0, flat 0, resolution 0 ABS_MT_TRACKING_ID : value 0, min 0, max 65535, fuzz 0, flat 0, resolution 0 ABS_MT_PRESSURE : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0
AB类型的区别说明见
kernel/Documentation/input/multi-touch-protocol.txt