Input: synaptics_i2c_rmi: Correct 2nd multi touch removing

When 2nd multi touch is removed, release point is (0,0) point.
To correct this, in removing 2nd multi touch,
we send last touched position of 2nd multi touch.
And this removes noise touch event and joystick event also.

Bug 896919

Change-Id: Icccaa3ccc28e613565ce696339b83d60335b344a
Reviewed-on: http://git-master/r/64008
Reviewed-by: Varun Colbert <vcolbert@nvidia.com>
Tested-by: Varun Colbert <vcolbert@nvidia.com>

Rebase-Id: Re3c488cd60c5b02ec43fa8f3e700dc93afbff043

1 files changed, 41 insertions, 17 deletions

diff --git a/drivers/input/touchscreen/synaptics_i2c_rmi.c b/drivers/input/touchscreen/synaptics_i2c_rmi.c
index 5729602cbb63..6f9b83af0359 100644
--- a/drivers/input/touchscreen/synaptics_i2c_rmi.c
+++ b/drivers/input/touchscreen/synaptics_i2c_rmi.c
@@ -25,6 +25,8 @@
 #include <linux/slab.h>
 #include <linux/synaptics_i2c_rmi.h>
 
+#define ABS_DIFF(a, b)   (((a) > (b)) ? ((a) - (b)) : ((b) - (a)))
+
 static struct workqueue_struct *synaptics_wq;
 
 struct synaptics_ts_data {
@@ -45,6 +47,7 @@ struct synaptics_ts_data {
 	int snap_up[2];
 	uint32_t flags;
 	int reported_finger_count;
+	int last_pos[2][2];
 	int8_t sensitivity_adjust;
 	int (*power)(int on);
 	struct early_suspend early_suspend;
@@ -136,6 +139,7 @@ static void synaptics_ts_work_func(struct work_struct *work)
 				break;
 			} else {
 				int pos[2][2];
+				int rmpos_x, rmpos_y;
 				int f, a;
 				int base;
 				/* int x = buf[3] | (uint16_t)(buf[2] & 0x1f) << 8; */
@@ -193,22 +197,19 @@ static void synaptics_ts_work_func(struct work_struct *work)
 					if (ts->flags & SYNAPTICS_SWAP_XY)
 						swap(pos[f][0], pos[f][1]);
 				}
-				if (z) {
-					input_report_abs(ts->input_dev, ABS_X, pos[0][0]);
-					input_report_abs(ts->input_dev, ABS_Y, pos[0][1]);
-				}
-				input_report_abs(ts->input_dev, ABS_PRESSURE, z);
-				input_report_abs(ts->input_dev, ABS_TOOL_WIDTH, w);
-				input_report_key(ts->input_dev, BTN_TOUCH, finger);
-				finger2_pressed = finger > 1 && finger != 7;
-				input_report_key(ts->input_dev, BTN_2, finger2_pressed);
-				if (finger2_pressed) {
-					input_report_abs(ts->input_dev, ABS_HAT0X, pos[1][0]);
-					input_report_abs(ts->input_dev, ABS_HAT0Y, pos[1][1]);
-				}
 
-				if (!finger)
+				if (!finger) {
 					z = 0;
+					if (ts->reported_finger_count > 0) {
+						pos[0][0] = ts->last_pos[0][0];
+						pos[0][1] = ts->last_pos[0][1];
+					}
+					else
+						continue; /* skip touch noise */
+				}
+				finger = (finger == 7) ? 1 : finger; /* correct wrong finger count */
+				finger2_pressed = finger > 1;
+
 				input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, z);
 				input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, w);
 				input_report_abs(ts->input_dev, ABS_MT_POSITION_X, pos[0][0]);
@@ -220,11 +221,37 @@ static void synaptics_ts_work_func(struct work_struct *work)
 					input_report_abs(ts->input_dev, ABS_MT_POSITION_X, pos[1][0]);
 					input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, pos[1][1]);
 					input_mt_sync(ts->input_dev);
+					ts->last_pos[1][0] = pos[1][0];
+					ts->last_pos[1][1] = pos[1][1];
 				} else if (ts->reported_finger_count > 1) {
+					/* check which point was removed */
+					if ((ABS_DIFF(pos[0][0],ts->last_pos[0][0]) +
+					ABS_DIFF(pos[0][1],ts->last_pos[0][1])) <
+					(ABS_DIFF(pos[0][0],ts->last_pos[1][0]) +
+					ABS_DIFF(pos[0][1],ts->last_pos[1][1]))) {
+						rmpos_x = ts->last_pos[1][0];
+						rmpos_y = ts->last_pos[1][1];
+					}
+					else {
+						rmpos_x = ts->last_pos[0][0];
+						rmpos_y = ts->last_pos[0][1];
+					}
 					input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0);
 					input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0);
+					input_report_abs(ts->input_dev, ABS_MT_POSITION_X, rmpos_x);
+					input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, rmpos_y);
 					input_mt_sync(ts->input_dev);
 				}
+
+				if (z) {
+					input_report_abs(ts->input_dev, ABS_X, pos[0][0]);
+					input_report_abs(ts->input_dev, ABS_Y, pos[0][1]);
+					ts->last_pos[0][0] = pos[0][0];
+					ts->last_pos[0][1] = pos[0][1];
+				}
+				input_report_abs(ts->input_dev, ABS_PRESSURE, z);
+				input_report_abs(ts->input_dev, ABS_TOOL_WIDTH, w);
+				input_report_key(ts->input_dev, BTN_TOUCH, finger);
 				ts->reported_finger_count = finger;
 				input_sync(ts->input_dev);
 			}
@@ -464,7 +491,6 @@ static int synaptics_ts_probe(
 	set_bit(EV_SYN, ts->input_dev->evbit);
 	set_bit(EV_KEY, ts->input_dev->evbit);
 	set_bit(BTN_TOUCH, ts->input_dev->keybit);
-	set_bit(BTN_2, ts->input_dev->keybit);
 	set_bit(EV_ABS, ts->input_dev->evbit);
 	inactive_area_left = inactive_area_left * max_x / 0x10000;
 	inactive_area_right = inactive_area_right * max_x / 0x10000;
@@ -503,8 +529,6 @@ static int synaptics_ts_probe(
 	input_set_abs_params(ts->input_dev, ABS_Y, -inactive_area_top, max_y + inactive_area_bottom, fuzz_y, 0);
 	input_set_abs_params(ts->input_dev, ABS_PRESSURE, 0, 255, fuzz_p, 0);
 	input_set_abs_params(ts->input_dev, ABS_TOOL_WIDTH, 0, 15, fuzz_w, 0);
-	input_set_abs_params(ts->input_dev, ABS_HAT0X, -inactive_area_left, max_x + inactive_area_right, fuzz_x, 0);
-	input_set_abs_params(ts->input_dev, ABS_HAT0Y, -inactive_area_top, max_y + inactive_area_bottom, fuzz_y, 0);
 	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, -inactive_area_left, max_x + inactive_area_right, fuzz_x, 0);
 	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, -inactive_area_top, max_y + inactive_area_bottom, fuzz_y, 0);
 	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, fuzz_p, 0);