On some laptops that have a Windows Precision Touchpad (imt) and

also a trackstick or separate physical buttons, imt was claiming all
report ids of the ihidev device preventing the trackstick/buttons
from attaching as a separate ims device on other report ids.

Just claim the report ids that imt needs and let ims attach to
others it may find.

Fixes two Dell Latitude laptops and tested in snaps for a bit.

3 files changed, 26 insertions, 13 deletions

diff --git a/sys/dev/i2c/ihidev.c b/sys/dev/i2c/ihidev.c
index 4c63eb5bae2..07e7b86fae5 100644
--- a/sys/dev/i2c/ihidev.c
+++ b/sys/dev/i2c/ihidev.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ihidev.c,v 1.22 2020/01/24 04:03:11 cheloha Exp $ */
+/* $OpenBSD: ihidev.c,v 1.23 2020/07/09 21:01:55 jcs Exp $ */
 /*
  * HID-over-i2c driver
  *
@@ -173,17 +173,22 @@ ihidev_attach(struct device *parent, struct device *self, void *aux)
 	iha.iaa = ia;
 	iha.parent = sc;
 
-	/* Look for a driver claiming all report IDs first. */
-	iha.reportid = IHIDEV_CLAIM_ALLREPORTID;
+	/* Look for a driver claiming multiple report IDs first. */
+	iha.reportid = IHIDEV_CLAIM_MULTIPLEID;
+	iha.nclaims = 0;
 	dev = config_found_sm((struct device *)sc, &iha, NULL,
 	    ihidev_submatch);
 	if (dev != NULL) {
-		for (repid = 0; repid < sc->sc_nrepid; repid++)
-			sc->sc_subdevs[repid] = (struct ihidev *)dev;
-		return;
+		for (repid = 0; repid < iha.nclaims; repid++) {
+			sc->sc_subdevs[iha.claims[repid]] =
+			    (struct ihidev *)dev;
+		}
 	}
 
 	for (repid = 0; repid < sc->sc_nrepid; repid++) {
+		if (sc->sc_subdevs[repid] != NULL)
+			continue;
+
 		if (hid_report_size(sc->sc_report, sc->sc_reportlen, hid_input,
 		    repid) == 0 &&
 		    hid_report_size(sc->sc_report, sc->sc_reportlen,
@@ -748,7 +753,7 @@ ihidev_print(void *aux, const char *pnp)
 	if (pnp)
 		printf("hid at %s", pnp);
 
-	if (iha->reportid != 0 && iha->reportid != IHIDEV_CLAIM_ALLREPORTID)
+	if (iha->reportid != 0)
 		printf(" reportid %d", iha->reportid);
 
 	return (UNCONF);
diff --git a/sys/dev/i2c/ihidev.h b/sys/dev/i2c/ihidev.h
index dde7cef5ab5..0404be65b06 100644
--- a/sys/dev/i2c/ihidev.h
+++ b/sys/dev/i2c/ihidev.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ihidev.h,v 1.7 2019/07/22 14:37:06 jcs Exp $ */
+/* $OpenBSD: ihidev.h,v 1.8 2020/07/09 21:01:56 jcs Exp $ */
 /*
  * HID-over-i2c driver
  *
@@ -112,7 +112,9 @@ struct ihidev_attach_arg {
 	struct i2c_attach_args	*iaa;
 	struct ihidev_softc	*parent;
 	uint8_t			 reportid;
-#define	IHIDEV_CLAIM_ALLREPORTID	255
+	uint8_t			 claims[16];
+	uint8_t			 nclaims;
+#define	IHIDEV_CLAIM_MULTIPLEID	255
 };
 
 struct i2c_hid_report_request {
diff --git a/sys/dev/i2c/imt.c b/sys/dev/i2c/imt.c
index 38169837338..5bd3894898f 100644
--- a/sys/dev/i2c/imt.c
+++ b/sys/dev/i2c/imt.c
@@ -1,9 +1,9 @@
-/* $OpenBSD: imt.c,v 1.4 2018/08/25 20:31:31 jcs Exp $ */
+/* $OpenBSD: imt.c,v 1.5 2020/07/09 21:01:56 jcs Exp $ */
 /*
  * HID-over-i2c multitouch trackpad driver for devices conforming to
  * Windows Precision Touchpad standard
  *
- * https://msdn.microsoft.com/en-us/library/windows/hardware/dn467314%28v=vs.85%29.aspx
+ * https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/windows-precision-touchpad-required-hid-top-level-collections
  *
  * Copyright (c) 2016 joshua stein <jcs@openbsd.org>
  *
@@ -79,13 +79,19 @@ int
 imt_match(struct device *parent, void *match, void *aux)
 {
 	struct ihidev_attach_arg *iha = (struct ihidev_attach_arg *)aux;
+	struct imt_softc sc;
 	int size;
 	void *desc;
 
-	if (iha->reportid == IHIDEV_CLAIM_ALLREPORTID) {
+	if (iha->reportid == IHIDEV_CLAIM_MULTIPLEID) {
 		ihidev_get_report_desc(iha->parent, &desc, &size);
-		if (imt_find_winptp_reports(iha->parent, desc, size, NULL))
+		if (imt_find_winptp_reports(iha->parent, desc, size, &sc)) {
+			iha->claims[0] = sc.sc_rep_input;
+			iha->claims[1] = sc.sc_rep_config;
+			iha->claims[2] = sc.sc_rep_cap;
+			iha->nclaims = 3;
 			return (IMATCH_DEVCLASS_DEVSUBCLASS);
+		}
 	}
 
 	return (IMATCH_NONE);