Input: MT - handle semi-mt devices in core

Most semi-mt drivers use the slots in a manual way, but really only
need to treat the finger count manually. With this patch, a semi-mt
driver may use the input-mt core for everything else.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c
index 71db193..d398f13 100644
--- a/drivers/input/input-mt.c
+++ b/drivers/input/input-mt.c
@@ -79,6 +79,8 @@
 	}
 	if (flags & INPUT_MT_DIRECT)
 		__set_bit(INPUT_PROP_DIRECT, dev->propbit);
+	if (flags & INPUT_MT_SEMI_MT)
+		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
 	if (flags & INPUT_MT_TRACK) {
 		unsigned int n2 = num_slots * num_slots;
 		mt->red = kcalloc(n2, sizeof(*mt->red), GFP_KERNEL);
@@ -246,6 +248,7 @@
 {
 	struct input_mt *mt = dev->mt;
 	struct input_mt_slot *s;
+	bool use_count = false;
 
 	if (!mt)
 		return;
@@ -259,7 +262,10 @@
 		}
 	}
 
-	input_mt_report_pointer_emulation(dev, (mt->flags & INPUT_MT_POINTER));
+	if ((mt->flags & INPUT_MT_POINTER) && !(mt->flags & INPUT_MT_SEMI_MT))
+		use_count = true;
+
+	input_mt_report_pointer_emulation(dev, use_count);
 
 	mt->frame++;
 }