[PATCH] Input: Do not add SYN_REPORT in between a single packet data

As mentioned in documentation, SYN_REPORT should be used to separate two packets
and should not be inserted in between a single packet as otherwise with multiple
SYN_REPORT in a single packet, input reader would not be able to know when the
packet ended really.

Documentation snippet:
* SYN_REPORT:
  - Used to synchronize and separate events into packets of input data changes
    occurring at the same moment in time. For example, motion of a mouse may set
    the REL_X and REL_Y values for one motion, then emit a SYN_REPORT. The next
    motion will emit more REL_X and REL_Y values and send another SYN_REPORT.

Signed-off-by: Aniroop Mathur <redacted>
---
 drivers/input/input.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 8806059..5b0b1ae 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c

@@ -401,12 +401,14 @@ static void input_handle_event(struct input_dev *dev,
 		if (dev->num_vals >= 2)
 			input_pass_values(dev, dev->vals, dev->num_vals);
 		dev->num_vals = 0;
-	} else if (dev->num_vals >= dev->max_vals - 2) {
-		dev->vals[dev->num_vals++] = input_value_sync;
-		input_pass_values(dev, dev->vals, dev->num_vals);
-		dev->num_vals = 0;
+	} else if (dev->num_vals >= dev->max_vals - 1) {
+		/* Pass all events except the newest event in order to
+		 * not suppress the immediate EV_SYN/SYN_REPORT event.
+		 */
+		input_pass_values(dev, dev->vals, dev->num_vals - 1);
+		dev->vals[0] = dev->vals[dev->num_vals - 1];
+		dev->num_vals = 1;
 	}
-
 }
 
 /**

-- 
2.6.2