psm: Fix three finger tap on elantech v4 touchpads

Fix an issue where a three finger tap would generate additional events
when fingers moved slightly during the tap.

Signed-off-by:	Robert Wahlberg <freebsd@robertwahlberg.se>
Pull Request:	https://github.com/freebsd/freebsd-src/pull/1792
Reviewed by:	wulf
MFC after:	1 month

This commit is contained in:

Robert Wahlberg

2025-12-01 23:42:15 +03:00

committed by

Vladimir Kondratyev

parent b6cad334e6

commit e3201cec83

1 changed files with 7 additions and 0 deletions

									
										sys/dev/atkbdc/psm.c
									
		+7
		
												View File
												
				@@ -4666,6 +4666,13 @@ proc_elantech(struct psm_softc *sc, packetbuf_t *pb, mousestatus_t *ms,

						mask = sc->elanaction.mask;

						nfingers = bitcount(mask);

						/* The motion packet can only update two fingers at a time.

						 * Copy the previous state to get all active fingers. */

						for (id = 0; id < ELANTECH_MAX_FINGERS; id++)

							if (sc->elanaction.mask & (1 << id))

								f[id] = sc->elanaction.fingers[id];

						/* Update finger positions from the new packet */

						scale = (pb->ipacket[0] & 0x10) ? 5 : 1;

						for (i = 0; i <= 3; i += 3) {

							id = ((pb->ipacket[i] & 0xe0) >> 5) - 1;