From 2a99775c336303d2efc43eab4f24b34722a28faa Mon Sep 17 00:00:00 2001
From: "Sergei A. Trusov" <sergei.a.trusov@ya.ru>
Date: Tue, 20 Jun 2017 18:08:35 +0200
Subject: [PATCH 11/16] Input: goodix: Add support for capacitive home button
On some x86 tablets with a Goodix touchscreen, the Windows logo on the
front is a capacitive home button. Touching this button results in a touch
with bit 4 of the first byte set, while only the lower 4 bits (0-3) are
used to indicate the number of touches.
Report a KEY_LEFTMETA press when this happens.
Note that the hardware might support more than one button, in which
case the "id" byte of coor_data would identify the button in question.
This is not implemented as we don't have access to hardware with
multiple buttons.
Signed-off-by: Sergei A. Trusov <sergei.a.trusov@ya.ru>
Acked-by: Bastien Nocera <hadess@hadess.net>
---
drivers/input/touchscreen/goodix.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index 240b16f3ee97..903137d9cf7d 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -267,6 +267,12 @@ static void goodix_process_events(struct goodix_ts_data *ts)
if (touch_num < 0)
return;
+ /*
+ * Bit 4 of the first byte reports the status of the capacitive
+ * Windows/Home button.
+ */
+ input_report_key(ts->input_dev, KEY_LEFTMETA, !!(point_data[0] & BIT(4)));
+
for (i = 0; i < touch_num; i++)
goodix_ts_report_touch(ts,
&point_data[1 + GOODIX_CONTACT_SIZE * i]);
@@ -612,6 +618,9 @@ static int goodix_request_input_dev(struct goodix_ts_data *ts)
ts->input_dev->id.product = ts->id;
ts->input_dev->id.version = ts->version;
+ /* Capacitive Windows/Home button on some devices */
+ input_set_capability(ts->input_dev, EV_KEY, KEY_LEFTMETA);
+
error = input_register_device(ts->input_dev);
if (error) {
dev_err(&ts->client->dev,
--
2.13.0