[PATCH v5 04/13] HID: playstation: add DualSense touchpad support.

[Roderick Colenbrander <roderick@xxxxxxxxxx>]

From: Roderick Colenbrander <roderick.colenbrander@xxxxxxxx>

Implement support for DualSense touchpad as a separate input device.

Signed-off-by: Roderick Colenbrander <roderick.colenbrander@xxxxxxxx>
---
 drivers/hid/hid-playstation.c | 66 +++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
index c5c450fc25db..64d6d736c435 100644
--- a/drivers/hid/hid-playstation.c
+++ b/drivers/hid/hid-playstation.c
@@ -60,9 +60,21 @@ struct ps_device {
 #define DS_STATUS_CHARGING		GENMASK(7, 4)
 #define DS_STATUS_CHARGING_SHIFT	4
 
+/*
+ * Status of a DualSense touch point contact.
+ * Contact IDs, with highest bit set are 'inactive'
+ * and any associated data is then invalid.
+ */
+#define DS_TOUCH_POINT_INACTIVE BIT(7)
+
+/* DualSense hardware limits */
+#define DS_TOUCHPAD_WIDTH	1920
+#define DS_TOUCHPAD_HEIGHT	1080
+
 struct dualsense {
 	struct ps_device base;
 	struct input_dev *gamepad;
+	struct input_dev *touchpad;
 };
 
 struct dualsense_touch_point {
@@ -272,6 +284,34 @@ static int ps_get_report(struct hid_device *hdev, uint8_t report_id, uint8_t *bu
 	return 0;
 }
 
+static struct input_dev *ps_touchpad_create(struct hid_device *hdev, int width, int height,
+		unsigned int num_contacts)
+{
+	struct input_dev *touchpad;
+	int ret;
+
+	touchpad = ps_allocate_input_dev(hdev, "Touchpad");
+	if (IS_ERR(touchpad))
+		return ERR_CAST(touchpad);
+
+	/* Map button underneath touchpad to BTN_LEFT. */
+	input_set_capability(touchpad, EV_KEY, BTN_LEFT);
+	__set_bit(INPUT_PROP_BUTTONPAD, touchpad->propbit);
+
+	input_set_abs_params(touchpad, ABS_MT_POSITION_X, 0, width - 1, 0, 0);
+	input_set_abs_params(touchpad, ABS_MT_POSITION_Y, 0, height - 1, 0, 0);
+
+	ret = input_mt_init_slots(touchpad, num_contacts, INPUT_MT_POINTER);
+	if (ret)
+		return ERR_PTR(ret);
+
+	ret = input_register_device(touchpad);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return touchpad;
+}
+
 static int dualsense_get_mac_address(struct dualsense *ds)
 {
 	uint8_t *buf;
@@ -304,6 +344,7 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	uint8_t battery_data, battery_capacity, charging_status, value;
 	int battery_status;
 	unsigned long flags;
+	int i;
 
 	/*
 	 * DualSense in USB uses the full HID report for reportID 1, but
@@ -346,6 +387,25 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	input_report_key(ds->gamepad, BTN_MODE,   ds_report->buttons[2] & DS_BUTTONS2_PS_HOME);
 	input_sync(ds->gamepad);
 
+	for (i = 0; i < ARRAY_SIZE(ds_report->points); i++) {
+		struct dualsense_touch_point *point = &ds_report->points[i];
+		bool active = (point->contact & DS_TOUCH_POINT_INACTIVE) ? false : true;
+
+		input_mt_slot(ds->touchpad, i);
+		input_mt_report_slot_state(ds->touchpad, MT_TOOL_FINGER, active);
+
+		if (active) {
+			int x = (point->x_hi << 8) | point->x_lo;
+			int y = (point->y_hi << 4) | point->y_lo;
+
+			input_report_abs(ds->touchpad, ABS_MT_POSITION_X, x);
+			input_report_abs(ds->touchpad, ABS_MT_POSITION_Y, y);
+		}
+	}
+	input_mt_sync_frame(ds->touchpad);
+	input_report_key(ds->touchpad, BTN_LEFT, ds_report->buttons[2] & DS_BUTTONS2_TOUCHPAD);
+	input_sync(ds->touchpad);
+
 	battery_data = ds_report->status & DS_STATUS_BATTERY_CAPACITY;
 	charging_status = (ds_report->status & DS_STATUS_CHARGING) >> DS_STATUS_CHARGING_SHIFT;
 
@@ -422,6 +482,12 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 		goto err;
 	}
 
+	ds->touchpad = ps_touchpad_create(hdev, DS_TOUCHPAD_WIDTH, DS_TOUCHPAD_HEIGHT, 2);
+	if (IS_ERR(ds->touchpad)) {
+		ret = PTR_ERR(ds->touchpad);
+		goto err;
+	}
+
 	ret = ps_device_register_battery(ps_dev);
 	if (ret)
 		goto err;
-- 
2.26.2