cd /sys/block/mmcblk0/device/
Checking if the "128GB" chip actually reports as a generic 4GB CID. emmc cid decoder
Bytes 3 to 8 (6 bytes) form the PNM. In our example: 53 45 4d 30 34 47 = SEM04G . That means "Samsung eMMC 4GB". emmc cid decoder