A TI CC2642 multirole connected to a smartphone will terminate connections unexpectedly by reporting HCI error code 0x8C - HW_FAIL_INADEQUATE_PKT_LEN.

The smartphone acts as a central, and the TI device acts as a peripheral.

In this instance, the issue occurred when an L2CAP B-frame carrying 40 bytes of information payload (for a total of 44 bytes when considering the 4-byte header) is fragmented into two parts of 3 bytes and 41 bytes, respectively. That is, the first fragment does not contain the full, 4-byte header that the stack expects and it throws the "inadequate packet length" error. 
Any fragment with less than 4 bytes will be rejected as described above.

This fragmentation is not a violation of the spec.