Input: atmel_mxt_ts - handle multiple input reports in one message

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Acked-by: Benson Leung <bleung@chromium.org>
Acked-by: Yufeng Shen <miletus@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 28 insertions, 8 deletions

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 7951d9bcee4a..97495c7edae8 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -654,6 +654,12 @@ 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)
 {
@@ -667,10 +673,12 @@ 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];
@@ -689,14 +697,28 @@ 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);
         }
 }
 
@@ -754,10 +776,8 @@ static irqreturn_t mxt_process_messages_until_invalid(struct mxt_data *data)
                 }
         } while (reportid != 0xff);
 
-        if (update_input) {
-                input_mt_report_pointer_emulation(data->input_dev, false);
-                input_sync(data->input_dev);
-        }
+        if (update_input)
+                mxt_input_sync(data->input_dev);
 
         return IRQ_HANDLED;
 }