--- acpi_ibm.c.orig	2018-06-18 20:05:09.510966000 +0200
+++ acpi_ibm.c	2018-06-18 20:02:43.835109000 +0200
@@ -349,7 +349,7 @@
 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)
@@ -425,9 +425,14 @@
 acpi_ibm_attach(device_t dev)
 {
 	int i;
+	int hkey;
 	struct acpi_ibm_softc	*sc;
 	char *maker, *product;
-	devclass_t		ec_devclass;
+	ACPI_OBJECT_LIST input;
+	ACPI_OBJECT params[1];
+	ACPI_OBJECT out_obj;
+	ACPI_BUFFER result;
+	devclass_t ec_devclass;
 
 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
 
@@ -456,21 +461,54 @@
 	sc->events_mask_supported = ACPI_SUCCESS(acpi_GetInteger(sc->handle,
 	    IBM_NAME_EVENTS_MASK_GET, &sc->events_initialmask));
 
+        if (ACPI_SUCCESS (acpi_GetInteger(sc->handle, "MHKV", &hkey)))
+	{
+		device_printf(dev, "Firmware version key 0x%X\n", hkey);
+	}
+	else
+	{
+		device_printf(dev, "Failed to get firmware version key\n");
+		return (EINVAL);
+	}
+
 	if (sc->events_mask_supported) {
 		SYSCTL_ADD_UINT(sc->sysctl_ctx,
 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO,
 		    "initialmask", CTLFLAG_RD,
 		    &sc->events_initialmask, 0, "Initial eventmask");
 
-		/* The availmask is the bitmask of supported events */
-		if (ACPI_FAILURE(acpi_GetInteger(sc->handle,
-		    IBM_NAME_EVENTS_AVAILMASK, &sc->events_availmask)))
-			sc->events_availmask = 0xffffffff;
+		switch(hkey >> 8)
+		{
+			case 1:
+				/* The availmask is the bitmask of supported events */
+				if (ACPI_FAILURE(acpi_GetInteger(sc->handle,
+								IBM_NAME_EVENTS_AVAILMASK, &sc->events_availmask)))
+					sc->events_availmask = 0xffffffff;
 
+				break;
+
+			case 2:
+				result.Length = sizeof(out_obj);
+				result.Pointer = &out_obj;
+				params[0].Type = ACPI_TYPE_INTEGER;
+				params[0].Integer.Value = 1;
+				input.Pointer = params;
+				input.Count = 1;
+
+				sc->events_availmask = 0xffffffff;
+
+				if (ACPI_SUCCESS(AcpiEvaluateObject (sc->handle,
+						IBM_NAME_EVENTS_AVAILMASK, &input, &result)))
+					sc->events_availmask = out_obj.Integer.Value;
+				break;
+
+			default:
+			break;
+		}
 		SYSCTL_ADD_UINT(sc->sysctl_ctx,
-		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO,
-		    "availmask", CTLFLAG_RD,
-		    &sc->events_availmask, 0, "Mask of supported events");
+				SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO,
+				"availmask", CTLFLAG_RD,
+				&sc->events_availmask, 0, "Mask of supported events");
 	}
 
 	/* Hook up proc nodes */