A little more information after looking around a bit. The linux [1] and freebsd [2] drivers accept all elantech touchpads with ic types from 6 up to 15 as using the v4 protocol.
The following patch extends the accepted ic types to that range (from the current set consisting of 6, 8, and 15). I cannot, however, test touchpads with ic types other than 13. 1. https://github.com/torvalds/linux/commit/10d900303f1c3a821eb0bef4e7b7ece16768fba4#diff-e91bc4802c6797fe9acbdca0ed240be9 2. https://github.com/freebsd/freebsd/commit/8b5fc46c359e276d4545b531a3d3eb15762d1783#diff-fac99891d1c5da0f566dbcc68ba62b22 Index: pms.c =================================================================== RCS file: /cvs/src/sys/dev/pckbc/pms.c,v retrieving revision 1.88 diff -u -p -r1.88 pms.c --- pms.c 26 Jan 2019 11:57:21 -0000 1.88 +++ pms.c 11 Aug 2019 16:36:30 -0000 @@ -1945,9 +1945,7 @@ elantech_get_hwinfo_v4(struct pms_softc if (synaptics_query(sc, ELANTECH_QUE_FW_VER, &fw_version)) return (-1); - if ((fw_version & 0x0f0000) >> 16 != 6 - && (fw_version & 0x0f0000) >> 16 != 8 - && (fw_version & 0x0f0000) >> 16 != 15) + if ((fw_version & 0x0f0000) >> 16 < 6) return (-1); elantech->fw_version = fw_version;
