Index: sys/dev/acpi_support/acpi_ibm.c
===================================================================
--- sys/dev/acpi_support/acpi_ibm.c
+++ sys/dev/acpi_support/acpi_ibm.c
@@ -129,6 +129,7 @@
 #define IBM_NAME_EVENTS_MASK_SET	"MHKM"
 #define IBM_NAME_EVENTS_GET		"MHKP"
 #define IBM_NAME_EVENTS_AVAILMASK	"MHKA"
+#define IBM_NAME_EVENTS_VERSION		"MHKV"
 
 /* Event Code */
 #define IBM_EVENT_LCD_BACKLIGHT		0x03
@@ -340,7 +341,7 @@
 DRIVER_MODULE(acpi_ibm, acpi, acpi_ibm_driver, acpi_ibm_devclass,
 	      0, 0);
 MODULE_DEPEND(acpi_ibm, acpi, 1, 1, 1);
-static char    *ibm_ids[] = {"IBM0068", "LEN0068", NULL};
+static char    *ibm_ids[] = {"IBM0068", "LEN0068", "LEN0268", NULL};
 
 static void
 ibm_led(void *softc, int onoff)
@@ -386,7 +387,10 @@
 static int
 acpi_ibm_attach(device_t dev)
 {
-	int i;
+	ACPI_OBJECT		p, *bufp;
+	ACPI_OBJECT_LIST	args;
+	ACPI_BUFFER		buf;
+	int hkey_version;
 	struct acpi_ibm_softc	*sc;
 	char *maker, *product;
 	devclass_t		ec_devclass;
@@ -424,11 +428,41 @@
 		    "initialmask", CTLFLAG_RD,
 		    &sc->events_initialmask, 0, "Initial eventmask");
 
-		/* The availmask is the bitmask of supported events */
+		/*
+		 * The availmask is the bitmask of supported events, it's determined
+		 * by calling MHKA. Old pre-0x100 versions of the hkey interface (MKHV)
+		 * take no parameter to determine the hotkey mask. Newer models
+		 * (post-2015, like T460, T470s, Carbon X1) take one integer parameter:
+		 *   1: Retrieve availmask like before
+		 *   2: Retrieve adaptive keyboard mask (currently not supported
+		 *      by this driver), only supported on models featuring
+		 *      the adaptive keyboard, otherwise returns 0
+		 */
 		if (ACPI_FAILURE(acpi_GetInteger(sc->handle,
-		    IBM_NAME_EVENTS_AVAILMASK, &sc->events_availmask)))
-			sc->events_availmask = 0xffffffff;
+		    IBM_NAME_EVENTS_VERSION, &hkey_version)))
+			hkey_version = 0x100; /* default to version 1 of the hkey interface */
 
+		if ((hkey_version >> 8) < 2) {
+			if (ACPI_FAILURE(acpi_GetInteger(sc->handle,
+			    IBM_NAME_EVENTS_AVAILMASK, &sc->events_availmask)))
+				sc->events_availmask = 0xffffffff;
+		} else {
+			p.Type = ACPI_TYPE_INTEGER;
+			p.Integer.Value = 1;
+			args.Count = 1;
+			args.Pointer = &p;
+			buf.Length = ACPI_ALLOCATE_BUFFER;
+			if (ACPI_FAILURE(AcpiEvaluateObjectTyped(sc->handle,
+			    IBM_NAME_EVENTS_AVAILMASK, &args, &buf,
+			    ACPI_TYPE_INTEGER)))
+				sc->events_availmask = 0xffffffff;
+			else {
+				bufp = buf.Pointer;
+				sc->events_availmask= bufp->Integer.Value;
+				AcpiOsFree(buf.Pointer);
+			}
+		}
+
 		SYSCTL_ADD_UINT(sc->sysctl_ctx,
 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO,
 		    "availmask", CTLFLAG_RD,
@@ -488,7 +522,7 @@
 	if (maker == NULL || product == NULL)
 		goto nosmbios;
 
-	for (i = 0; i < nitems(acpi_ibm_models); i++) {
+	for (int i = 0; i < nitems(acpi_ibm_models); i++) {
 		if (strcmp(maker, acpi_ibm_models[i].maker) == 0 &&
 		    strcmp(product, acpi_ibm_models[i].product) == 0) {
 			ACPI_SERIAL_BEGIN(ibm);