Hi,

On 2017년 02월 10일 11:17, Andi Shyti wrote:

The stmfts (ST-Microelectronics FingerTip S) touchscreen device
is a capacitive multi-touch controller mainly for mobile use.

It's connected through i2c bus at the address 0x49 and it
interfaces with userspace through input event interface.

At the current state it provides a touchscreen multitouch
functionality up to 10 fingers. Each finger is enumerated with a
distinctive id (from 0 to 9).

If enabled the device can support single "touch" hovering, by
providing three coordinates, x, y and distance.

It is possible to select the touchkey functionality which
provides a basic two keys interface for "home" and "back" menu,
typical in mobile phones.

Signed-off-by: Andi Shyti <redacted>
---
 drivers/input/touchscreen/Kconfig  |  12 +
 drivers/input/touchscreen/Makefile |   1 +
 drivers/input/touchscreen/stmfts.c | 794 +++++++++++++++++++++++++++++++++++++
 3 files changed, 807 insertions(+)
 create mode 100644 drivers/input/touchscreen/stmfts.c

[snip]

+static void stmfts_parse_event(struct stmfts_data *sdata, u8 event[])
+{
+	int ret;
+	u8 id, t_id = 0;
+	u16 x, y, z, maj, min, orientation, area;
+
+	id = event[0];
+
+	do {
+		mutex_lock(&sdata->mutex);
+		if (sdata->in_touch) {
+			id = event[0] & STMFTS_MASK_EVENT_ID;
+			t_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;
+		} else {
+			id = event[0];
+			t_id = 0;
+		}
+
+		switch (id) {
+		case STMFTS_EV_NO_EVENT:
+			break;
+
+		case STMFTS_EV_MULTI_TOUCH_ENTER:
+		case STMFTS_EV_MULTI_TOUCH_LEAVE:
+		case STMFTS_EV_MULTI_TOUCH_MOTION:
+			if (id == STMFTS_EV_MULTI_TOUCH_ENTER) {
+				if (!(sdata->in_touch++))
+					input_mt_report_slot_state(
+							sdata->input,
+							MT_TOOL_FINGER, true);
+			} else if (id == STMFTS_EV_MULTI_TOUCH_LEAVE) {
+				if (!(--sdata->in_touch))
+					input_mt_report_slot_state(
+							sdata->input,
+							MT_TOOL_FINGER, false);
+			}
+
+			x = event[1] | ((event[2] & STMFTS_MASK_X_MSB) << 8);
+			y = (event[2] >> 4) | (event[3] << 4);
+
+			maj = event[4];
+			min = event[5];
+			orientation = event[6];
+			area = event[7];
+
+			input_mt_slot(sdata->input, t_id);
+			input_report_abs(sdata->input, ABS_MT_POSITION_X, x);
+			input_report_abs(sdata->input, ABS_MT_POSITION_Y, y);
+			input_report_abs(sdata->input, ABS_MT_TOUCH_MAJOR, maj);
+			input_report_abs(sdata->input, ABS_MT_TOUCH_MINOR, min);
+			input_report_abs(sdata->input, ABS_MT_PRESSURE, area);
+			input_report_abs(sdata->input, ABS_MT_ORIENTATION,
+								orientation);
+			input_sync(sdata->input);
+

When I tested this patch on TM2 board, It looks like it is not well working.
So, I tried to check the input event by using the evtest tool.
But, the result don't show the proper ABS_MT_TRACKING_ID event.
[1] https://cgit.freedesktop.org/evtest/

According to the mutlti-touch-protocol.txt[2], there are two multi-touch protocol.
As far as I knew, this driver supports the Protocol B which needs
the ABS_MT_TRACKING_ID according to the multi-touch-protocol.txt[2].
[2] Documentation/input/mutlti-touch-protocol.txt
 
In our test, the ABS_MT_TRACKING_ID is showed only one time.
After pressing/releasing finger from touchscreen on first time,
there are no ABS_MT_TRACKING_ID information from second try with finger.

I guess that input_mt_report_slot_state() is not calling properly.

+			break;
+
+		case STMFTS_EV_HOVER_ENTER:
+		case STMFTS_EV_HOVER_LEAVE:
+		case STMFTS_EV_HOVER_MOTION:
+			x = (event[2] << 4) | (event[4] >> 4);
+			y = (event[3] << 4) | (event[4] & STMFTS_MASK_Y_LSB);
+			z = event[5];
+			orientation = event[6] & STMFTS_MASK_Y_LSB;
+
+			input_report_abs(sdata->input, ABS_X, x);
+			input_report_abs(sdata->input, ABS_Y, y);
+			input_report_abs(sdata->input, ABS_DISTANCE, z);
+			input_sync(sdata->input);
+
+			break;
+

[snip]


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics