[PATCH 27/53] Input: atmel_mxt_ts - Handle multiple input reports in one message

[Nick Dyer <nick.dyer@itdev.co.uk>]

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Acked-by: Benson Leung <bleung@chromium.org>
---
 drivers/input/touchscreen/atmel_mxt_ts.c |   34 +++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index ad8b803..c91b22f 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -632,6 +632,12 @@ static void mxt_input_button(struct mxt_data *data, struct mxt_message *message)
 	}
 }
 
+static void mxt_input_sync(struct input_dev *input_dev)
+{
+	input_mt_report_pointer_emulation(input_dev, false);
+	input_sync(input_dev);
+}
+
 static void mxt_input_touchevent(struct mxt_data *data,
 				      struct mxt_message *message, int id)
 {
@@ -649,10 +655,12 @@ static void mxt_input_touchevent(struct mxt_data *data,
 
 	x = (message->message[1] << 4) | ((message->message[3] >> 4) & 0xf);
 	y = (message->message[2] << 4) | ((message->message[3] & 0xf));
+
+	/* Handle 10/12 bit switching */
 	if (data->max_x < 1024)
-		x = x >> 2;
+		x >>= 2;
 	if (data->max_y < 1024)
-		y = y >> 2;
+		y >>= 2;
 
 	area = message->message[4];
 	amplitude = message->message[5];
@@ -671,14 +679,26 @@ static void mxt_input_touchevent(struct mxt_data *data,
 		x, y, area, amplitude);
 
 	input_mt_slot(input_dev, id);
-	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER,
-				   status & MXT_T9_DETECT);
 
 	if (status & MXT_T9_DETECT) {
+		/* Multiple bits may be set if the host is slow to read the
+		 * status messages, indicating all the events that have
+		 * happened */
+		if (status & MXT_T9_RELEASE) {
+			input_mt_report_slot_state(input_dev,
+						   MT_TOOL_FINGER, 0);
+			mxt_input_sync(input_dev);
+		}
+
+		/* Touch active */
+		input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, 1);
 		input_report_abs(input_dev, ABS_MT_POSITION_X, x);
 		input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
 		input_report_abs(input_dev, ABS_MT_PRESSURE, amplitude);
 		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, area);
+	} else {
+		/* Touch no longer active, close out slot */
+		input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, 0);
 	}
 }
 
@@ -741,10 +761,8 @@ static irqreturn_t mxt_process_messages_until_invalid(struct mxt_data *data)
 			mxt_dump_message(dev, &message);
 	} while (reportid != MXT_RPTID_NOMSG);
 
-	if (data->enable_reporting && update_input) {
-		input_mt_report_pointer_emulation(data->input_dev, false);
-		input_sync(data->input_dev);
-	}
+	if (data->enable_reporting && update_input)
+		mxt_input_sync(data->input_dev);
 
 	return IRQ_HANDLED;
 }
-- 
1.7.10.4