Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit eca3be9b authored by Hans de Goede's avatar Hans de Goede Committed by Dmitry Torokhov
Browse files

Input: silead - add support for capactive home button found on some x86 tablets 



On some x86 tablets with a silead touchscreen the windows logo on the
front is a capacitive home button. Touching this button results in a touch
with bits 12-15 of the Y coordinates set, while normally only the lower 12
are used.

Detect this and report a KEY_LEFTMETA press when this happens. Note for
now we only respond to the Y coordinate bits 12-15 containing 0x01, on some
tablets *without* a capacative button I've noticed these bits containing
0x04 when crossing the edges of the screen.

Acked-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
parent da7bdec4

Documentation/devicetree/bindings/input/touchscreen/silead_gsl1680.txt

+2 −0
Original line number Diff line number Diff line
@@ -23,6 +23,8 @@ Optional properties: 
- touchscreen-inverted-y  : See touchscreen.txt

- touchscreen-swapped-x-y : See touchscreen.txt

- silead,max-fingers	  : maximum number of fingers the touchscreen can detect

- silead,home-button	  : Boolean, set to true on devices which have a

			    capacitive home-button build into the touchscreen

- vddio-supply		  : regulator phandle for controller VDDIO

- avdd-supply		  : regulator phandle for controller AVDD

drivers/input/touchscreen/silead.c

+35 −11
Original line number Diff line number Diff line
@@ -56,7 +56,7 @@ 
#define SILEAD_POINT_Y_MSB_OFF	0x01

#define SILEAD_POINT_X_OFF	0x02

#define SILEAD_POINT_X_MSB_OFF	0x03

#define SILEAD_TOUCH_ID_MASK	0xF0

#define SILEAD_EXTRA_DATA_MASK	0xF0



#define SILEAD_CMD_SLEEP_MIN	10000

#define SILEAD_CMD_SLEEP_MAX	20000
@@ -109,6 +109,9 @@ static int silead_ts_request_input_dev(struct silead_ts_data *data) 
			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |

			    INPUT_MT_TRACK);



	if (device_property_read_bool(dev, "silead,home-button"))

		input_set_capability(data->input, EV_KEY, KEY_LEFTMETA);



	data->input->name = SILEAD_TS_NAME;

	data->input->phys = "input/ts";

	data->input->id.bustype = BUS_I2C;
@@ -139,7 +142,8 @@ static void silead_ts_read_data(struct i2c_client *client) 
	struct input_dev *input = data->input;

	struct device *dev = &client->dev;

	u8 *bufp, buf[SILEAD_TS_DATA_LEN];

	int touch_nr, error, i;

	int touch_nr, softbutton, error, i;

	bool softbutton_pressed = false;



	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,

					      SILEAD_TS_DATA_LEN, buf);
@@ -148,21 +152,40 @@ static void silead_ts_read_data(struct i2c_client *client) 
		return;

	}



	touch_nr = buf[0];

	if (touch_nr > data->max_fingers) {

	if (buf[0] > data->max_fingers) {

		dev_warn(dev, "More touches reported then supported %d > %d\n",

			 touch_nr, data->max_fingers);

		touch_nr = data->max_fingers;

			 buf[0], data->max_fingers);

		buf[0] = data->max_fingers;

	}



	touch_nr = 0;

	bufp = buf + SILEAD_POINT_DATA_LEN;

	for (i = 0; i < touch_nr; i++, bufp += SILEAD_POINT_DATA_LEN) {

		/* Bits 4-7 are the touch id */

		data->id[i] = (bufp[SILEAD_POINT_X_MSB_OFF] &

			       SILEAD_TOUCH_ID_MASK) >> 4;

		touchscreen_set_mt_pos(&data->pos[i], &data->prop,

	for (i = 0; i < buf[0]; i++, bufp += SILEAD_POINT_DATA_LEN) {

		softbutton = (bufp[SILEAD_POINT_Y_MSB_OFF] &

			      SILEAD_EXTRA_DATA_MASK) >> 4;



		if (softbutton) {

			/*

			 * For now only respond to softbutton == 0x01, some

			 * tablets *without* a capacative button send 0x04

			 * when crossing the edges of the screen.

			 */

			if (softbutton == 0x01)

				softbutton_pressed = true;



			continue;

		}



		/*

		 * Bits 4-7 are the touch id, note not all models have

		 * hardware touch ids so atm we don't use these.

		 */

		data->id[touch_nr] = (bufp[SILEAD_POINT_X_MSB_OFF] &

				      SILEAD_EXTRA_DATA_MASK) >> 4;

		touchscreen_set_mt_pos(&data->pos[touch_nr], &data->prop,

			get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,

			get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);

		touch_nr++;

	}



	input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
@@ -178,6 +201,7 @@ static void silead_ts_read_data(struct i2c_client *client) 
	}



	input_mt_sync_frame(input);

	input_report_key(input, KEY_LEFTMETA, softbutton_pressed);

	input_sync(input);

}