[PATCH v2] Input: goodix: Add support for capacitive home button found on some x86 tablets
From: Sergei A. Trusov <hidden>
Date: 2017-06-20 11:16:01
Subsystem:
goodix touchscreen, input (keyboard, mouse, joystick, touchscreen) drivers, the rest · Maintainers:
Hans de Goede, Dmitry Torokhov, Linus Torvalds
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 normally only the lower 4 bits are used to indicate the number of touches. Detect this and report a KEY_LEFTMETA press when this happens. Note the hardware might support more than one button, the number of a button is reported by the 'id' byte of coor_data. Now we ignore button id. Signed-off-by: Sergei A. Trusov <redacted> --- 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..c1bb59c96dbd 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] & 0x10)); + 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,