LinuxStatefulMultiTouchProcessor has an implementation of multitouch that should work with Protocol B devices (https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt).

We don't have any protocol B hardware, but we can at least verify that we can work with the protocol as it is documented:

Protocol Example B
------------------

Here is what a minimal event sequence for a two-contact touch would look
like for a type B device:

   ABS_MT_SLOT 0
   ABS_MT_TRACKING_ID 45
   ABS_MT_POSITION_X x[0]
   ABS_MT_POSITION_Y y[0]
   ABS_MT_SLOT 1
   ABS_MT_TRACKING_ID 46
   ABS_MT_POSITION_X x[1]
   ABS_MT_POSITION_Y y[1]
   SYN_REPORT

Here is the sequence after moving contact 45 in the x direction:

   ABS_MT_SLOT 0
   ABS_MT_POSITION_X x[0]
   SYN_REPORT

Here is the sequence after lifting the contact in slot 0:

   ABS_MT_TRACKING_ID -1
   SYN_REPORT

The slot being modified is already 0, so the ABS_MT_SLOT is omitted. The
message removes the association of slot 0 with contact 45, thereby
destroying contact 45 and freeing slot 0 to be reused for another contact.

Finally, here is the sequence after lifting the second contact:

   ABS_MT_SLOT 1
   ABS_MT_TRACKING_ID -1
   SYN_REPORT