Commit 5ede7f0c authored by Hans de Goede's avatar Hans de Goede Committed by Dmitry Torokhov
Browse files

Input: goodix - add pen support 

Some Goodix touchscreens have support for a (Goodix) active pen, add
support for this. The info on how to detect when a pen is down and to
detect when the stylus buttons are pressed was lifted from the out
of tree Goodix driver with pen support written by Adya:
https://gitlab.com/AdyaAdya/goodix-touchscreen-linux-driver/

Since there is no way to tell if pen support is present, the registering
of the pen input_dev is delayed till the first pen event is detected.

This has been tested on a Trekstor Surftab duo W1, a Chuwi Hi13 and
a Cyberbook T116 tablet.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=202161
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204513


Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211207100754.31155-3-hdegoede@redhat.com



Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
parent 5d8dfaa7

drivers/input/touchscreen/goodix.c

+120 −2
Original line number Diff line number Diff line
@@ -296,6 +296,107 @@ static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data) 
	return -ENOMSG;

}



static struct input_dev *goodix_create_pen_input(struct goodix_ts_data *ts)

{

	struct device *dev = &ts->client->dev;

	struct input_dev *input;



	input = devm_input_allocate_device(dev);

	if (!input)

		return NULL;



	input_alloc_absinfo(input);

	if (!input->absinfo) {

		input_free_device(input);

		return NULL;

	}



	input->absinfo[ABS_X] = ts->input_dev->absinfo[ABS_MT_POSITION_X];

	input->absinfo[ABS_Y] = ts->input_dev->absinfo[ABS_MT_POSITION_Y];

	__set_bit(ABS_X, input->absbit);

	__set_bit(ABS_Y, input->absbit);

	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);



	input_set_capability(input, EV_KEY, BTN_TOUCH);

	input_set_capability(input, EV_KEY, BTN_TOOL_PEN);

	input_set_capability(input, EV_KEY, BTN_STYLUS);

	input_set_capability(input, EV_KEY, BTN_STYLUS2);

	__set_bit(INPUT_PROP_DIRECT, input->propbit);

	/*

	 * The resolution of these touchscreens is about 10 units/mm, the actual

	 * resolution does not matter much since we set INPUT_PROP_DIRECT.

	 * Userspace wants something here though, so just set it to 10 units/mm.

	 */

	input_abs_set_res(input, ABS_X, 10);

	input_abs_set_res(input, ABS_Y, 10);



	input->name = "Goodix Active Pen";

	input->phys = "input/pen";

	input->id.bustype = BUS_I2C;

	if (kstrtou16(ts->id, 10, &input->id.product))

		input->id.product = 0x1001;

	input->id.version = ts->version;



	if (input_register_device(input) != 0) {

		input_free_device(input);

		return NULL;

	}



	return input;

}



static void goodix_ts_report_pen_down(struct goodix_ts_data *ts, u8 *data)

{

	int input_x, input_y, input_w;

	u8 key_value;



	if (!ts->input_pen) {

		ts->input_pen = goodix_create_pen_input(ts);

		if (!ts->input_pen)

			return;

	}



	if (ts->contact_size == 9) {

		input_x = get_unaligned_le16(&data[4]);

		input_y = get_unaligned_le16(&data[6]);

		input_w = get_unaligned_le16(&data[8]);

	} else {

		input_x = get_unaligned_le16(&data[2]);

		input_y = get_unaligned_le16(&data[4]);

		input_w = get_unaligned_le16(&data[6]);

	}



	touchscreen_report_pos(ts->input_pen, &ts->prop, input_x, input_y, false);

	input_report_abs(ts->input_pen, ABS_PRESSURE, input_w);



	input_report_key(ts->input_pen, BTN_TOUCH, 1);

	input_report_key(ts->input_pen, BTN_TOOL_PEN, 1);



	if (data[0] & GOODIX_HAVE_KEY) {

		key_value = data[1 + ts->contact_size];

		input_report_key(ts->input_pen, BTN_STYLUS, key_value & 0x10);

		input_report_key(ts->input_pen, BTN_STYLUS2, key_value & 0x20);

	} else {

		input_report_key(ts->input_pen, BTN_STYLUS, 0);

		input_report_key(ts->input_pen, BTN_STYLUS2, 0);

	}



	input_sync(ts->input_pen);

}



static void goodix_ts_report_pen_up(struct goodix_ts_data *ts)

{

	if (!ts->input_pen)

		return;



	input_report_key(ts->input_pen, BTN_TOUCH, 0);

	input_report_key(ts->input_pen, BTN_TOOL_PEN, 0);

	input_report_key(ts->input_pen, BTN_STYLUS, 0);

	input_report_key(ts->input_pen, BTN_STYLUS2, 0);



	input_sync(ts->input_pen);

}



static void goodix_ts_report_touch_8b(struct goodix_ts_data *ts, u8 *coor_data)

{

	int id = coor_data[0] & 0x0F;
@@ -326,6 +427,14 @@ static void goodix_ts_report_touch_9b(struct goodix_ts_data *ts, u8 *coor_data) 
	input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);

}



static void goodix_ts_release_keys(struct goodix_ts_data *ts)

{

	int i;



	for (i = 0; i < GOODIX_MAX_KEYS; i++)

		input_report_key(ts->input_dev, ts->keymap[i], 0);

}



static void goodix_ts_report_key(struct goodix_ts_data *ts, u8 *data)

{

	int touch_num;
@@ -340,8 +449,7 @@ static void goodix_ts_report_key(struct goodix_ts_data *ts, u8 *data) 
				input_report_key(ts->input_dev,

						 ts->keymap[i], 1);

	} else {

		for (i = 0; i < GOODIX_MAX_KEYS; i++)

			input_report_key(ts->input_dev, ts->keymap[i], 0);

		goodix_ts_release_keys(ts);

	}

}
@@ -363,6 +471,15 @@ static void goodix_process_events(struct goodix_ts_data *ts) 
	if (touch_num < 0)

		return;



	/* The pen being down is always reported as a single touch */

	if (touch_num == 1 && (point_data[1] & 0x80)) {

		goodix_ts_report_pen_down(ts, point_data);

		goodix_ts_release_keys(ts);

		goto sync; /* Release any previousle registered touches */

	} else {

		goodix_ts_report_pen_up(ts);

	}



	goodix_ts_report_key(ts, point_data);



	for (i = 0; i < touch_num; i++)
@@ -373,6 +490,7 @@ static void goodix_process_events(struct goodix_ts_data *ts) 
			goodix_ts_report_touch_8b(ts,

				&point_data[1 + ts->contact_size * i]);



sync:

	input_mt_sync_frame(ts->input_dev);

	input_sync(ts->input_dev);

}

drivers/input/touchscreen/goodix.h

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ struct goodix_chip_data { 
struct goodix_ts_data {

	struct i2c_client *client;

	struct input_dev *input_dev;

	struct input_dev *input_pen;

	const struct goodix_chip_data *chip;

	const char *firmware_name;

	struct touchscreen_properties prop;