ENGR00271359 Add Multi-touch support

The previous behavior of the driver did not work properly with Qt5
QtQuick multi touch-point gestures, due to how touch-points are
reported when removing a touch-point. My interpretation of the
available documentation [1] was that the driver should report all
touch-points between SYN_REPORTs, but it is not explicitly stated so.
I've found another mail-thread [2] where the creator of the protocol
states:

"The protocol defines a generic way of sending a variable amount of
contacts. The contact count is obtained by counting the number of
non-empty finger packets between SYN_REPORT events."-Henrik Rydberg

I think this verifies my assumption that all touch-points should be
reported between SYN_REPORTs, otherwise it can not be used to obtain
the count.

[1] https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt
[2] http://lists.x.org/archives/xorg-devel/2010-March/006466.html

Signed-off-by: Erik Boto <erik.boto@pelagicore.com>
Signed-off-by: Mahesh Mahadevan <Mahesh.Mahadevan@freescale.com>
(cherry picked from commit 7cba001c5a502680f6dbf902821726779a9c9287)

1 files changed, 18 insertions, 18 deletions

diff --git a/drivers/input/touchscreen/egalax_ts.c b/drivers/input/touchscreen/egalax_ts.c
index 0b6cde77c421..271f82035505 100644
--- a/drivers/input/touchscreen/egalax_ts.c
+++ b/drivers/input/touchscreen/egalax_ts.c
@@ -133,7 +133,6 @@ retry:
 	}
 
 	if (down) {
-		/* should also report old pointers */
 		events[id].valid = valid;
 		events[id].status = down;
 		events[id].x = x;
@@ -144,23 +143,6 @@ retry:
 		input_report_abs(input_dev, ABS_Y, y);
 		input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
 		input_report_abs(input_dev, ABS_PRESSURE, 1);
-#else
-		for (i = 0; i < MAX_SUPPORT_POINTS; i++) {
-			if (!events[i].valid)
-				continue;
-			dev_dbg(&client->dev, "report id:%d valid:%d x:%d y:%d",
-				i, valid, x, y);
-
-			input_report_abs(input_dev,
-					 ABS_MT_TRACKING_ID, i);
-			input_report_abs(input_dev,
-					 ABS_MT_TOUCH_MAJOR, 1);
-			input_report_abs(input_dev,
-					 ABS_MT_POSITION_X, events[i].x);
-			input_report_abs(input_dev,
-					 ABS_MT_POSITION_Y, events[i].y);
-			input_mt_sync(input_dev);
-		}
 #endif
 	} else {
 		dev_dbg(&client->dev, "release id:%d\n", id);
@@ -176,6 +158,24 @@ retry:
 #endif
 	}
 
+#ifndef CONFIG_TOUCHSCREEN_EGALAX_SINGLE_TOUCH
+	/* report all pointers */
+	for (i = 0; i < MAX_SUPPORT_POINTS; i++) {
+		if (!events[i].valid)
+			continue;
+		dev_dbg(&client->dev, "report id:%d valid:%d x:%d y:%d",
+			i, valid, x, y);
+			input_report_abs(input_dev,
+				 ABS_MT_TRACKING_ID, i);
+		input_report_abs(input_dev,
+				 ABS_MT_TOUCH_MAJOR, 1);
+		input_report_abs(input_dev,
+				 ABS_MT_POSITION_X, events[i].x);
+		input_report_abs(input_dev,
+				 ABS_MT_POSITION_Y, events[i].y);
+		input_mt_sync(input_dev);
+	}
+#endif
 	input_sync(input_dev);
 	return IRQ_HANDLED;
 }