touchscreen_mmi: clip area support

This introduces a new class method to suppress touch events sourced
outside or within specified clip area. To enable suppressing touch
events reported outside specified clip area, add the following DT
property:

mmi,clip-area = <xUL yUL xBR yBR>;

Suppressing touch events from within requires DT property:

mmi,clip-inversion;

Class driver's method will send forced lift event when an active
touch moves outside/within clip area and indicate this to the vendor
driver by setting type to TS_COORDINATE_ACTION_FORCE_LIFT in
touch_event_data structure.

Change-Id: I327af4441e179e381be97cb8083698d76882caa8
Signed-off-by: Konstantin Makariev <hcv867@motorola.com>
Reviewed-on: https://gerrit.mot.com/2641660
SME-Granted: SME Approvals Granted
SLTApproved: Slta Waiver
Tested-by: Jira Key
Reviewed-by: <zhuwg1@motorola.com>
Reviewed-by: Jun Weng <wengjun1@motorola.com>
Reviewed-by: Qing Chang <qing@motorola.com>
Submit-Approved: Jira Key

drivers/input/touchscreen/touchscreen_mmi/touchscreen_mmi_class.c

@@ -809,6 +809,29 @@ static int ts_mmi_default_pinctrl(struct device *parent, int on)
 	return 0;
 }
 
+static int ts_mmi_clip_event_handler(struct device *parent,
+			struct touch_event_data *tev, struct input_dev *input_dev)
+{
+	struct ts_mmi_dev *touch_cdev = ts_mmi_dev_to_cdev(parent);
+	bool inside;
+
+	inside = (tev->x >= touch_cdev->clip.xUL) && (tev->x <= touch_cdev->clip.xBR) &&
+		 (tev->y >= touch_cdev->clip.yUL) && (tev->y <= touch_cdev->clip.yBR);
+
+	if (inside == touch_cdev->clip.inversion) {
+		if (tev->type == TS_COORDINATE_ACTION_MOVE) {
+			/* cancel active touch when it falls off the clip area */
+			input_mt_slot(input_dev, tev->id);
+			input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false);
+			/* indicate cancelled touch to vendor driver */
+			tev->type = TS_COORDINATE_ACTION_FORCE_LIFT;
+		}
+		tev->skip_report = true;
+	}
+
+	return 0;
+}
+
 /**
  * ts_mmi_dev_register - register a new object of ts_mmi_dev class.
  * @parent: The device to register.
@@ -955,6 +978,11 @@ int ts_mmi_dev_register(struct device *parent,
 		}
 	}
 
+	if (touch_cdev->pdata.clip_area_ctrl) {
+		/* export report touch event function to vendor */
+		touch_cdev->mdata->exports.clip_touch_event = ts_mmi_clip_event_handler;
+	}
+
 	dev_info(DEV_TS, "Registered touchscreen device: %s.\n", class_fname);
 
 	return 0;

drivers/input/touchscreen/touchscreen_mmi/touchscreen_mmi_panel.c

@@ -47,7 +47,7 @@ int ts_mmi_parse_dt(struct ts_mmi_dev *touch_cdev,
 {
 	struct device_node *chosen;
 	struct ts_mmi_dev_pdata *ppdata = &touch_cdev->pdata;
-	u32 coords[2];
+	u32 coords[4];
 
 	dev_info(DEV_TS, "%s: Start parse touchscreen mmi device tree.\n", __func__);
 	if (!of_property_read_string(of_node, "mmi,class-entry-name", &ppdata->class_entry_name))
@@ -172,6 +172,20 @@ int ts_mmi_parse_dt(struct ts_mmi_dev *touch_cdev,
 		ppdata->support_liquid_detection = true;
 	}
 
+	if (!of_property_read_u32_array(of_node, "mmi,clip-area", coords, 4)) {
+		ppdata->clip_area_ctrl = true;
+		touch_cdev->clip.xUL = coords[0];
+		touch_cdev->clip.yUL = coords[1];
+		touch_cdev->clip.xBR = coords[2];
+		touch_cdev->clip.yBR = coords[3];
+		if (of_property_read_bool(of_node, "mmi,clip-inversion"))
+			touch_cdev->clip.inversion = true;
+		dev_info(DEV_TS, "%s: clip %sarea: (%u,%u) (%u,%u)\n", __func__,
+			touch_cdev->clip.inversion ? "IN " : "OUT ",
+			touch_cdev->clip.xUL, touch_cdev->clip.yUL,
+			touch_cdev->clip.xBR, touch_cdev->clip.yBR);
+	}
+
 	chosen = of_find_node_by_name(NULL, "chosen");
 	if (chosen) {
 		struct device_node *child;

include/linux/touchscreen_mmi.h

@@ -246,7 +246,8 @@ enum touch_event_mode {
 	TS_COORDINATE_ACTION_NONE = 0,
 	TS_COORDINATE_ACTION_PRESS,
 	TS_COORDINATE_ACTION_RELEASE,
-	TS_COORDINATE_ACTION_MOVE
+	TS_COORDINATE_ACTION_MOVE,
+	TS_COORDINATE_ACTION_FORCE_LIFT
 };
 
 enum TS_FW_UPGRADE_MODE {
@@ -270,6 +271,11 @@ struct gesture_event_data {
 	};
 };
 
+struct touch_clip_area {
+	unsigned xUL, yUL, xBR, yBR;
+	bool inversion; /* clip inside (when true) or outside otherwise */
+};
+
 /**
  * struct touchscreen_mmi_class_methods - export class methods to vendor
  *
@@ -282,6 +288,7 @@ struct ts_mmi_class_methods {
 	int     (*get_class_fname)(struct device *dev , const char **fname);
 	int     (*get_supplier)(struct device *dev , const char **sname);
 	int     (*report_touch_event)(struct touch_event_data *tev, struct input_dev *input_dev);
+	int     (*clip_touch_event)(struct device *dev, struct touch_event_data *tev, struct input_dev *input_dev);
 	int     (*report_liquid_detection_status)(struct device *parent, int status);
 	struct kobject *kobj_notify;
 };
@@ -434,6 +441,7 @@ struct ts_mmi_dev_pdata {
 	bool		poison_slot_ctrl;
 	bool		active_region_ctrl;
 	bool		support_liquid_detection;
+	bool		clip_area_ctrl;
 	int		max_x;
 	int		max_y;
 	int		fod_x;
@@ -540,6 +548,7 @@ struct ts_mmi_dev {
 	int			update_baseline;
 	struct attribute_group	*extern_group;
 	struct list_head	node;
+	struct touch_clip_area clip;
 	/*
 	 * vendor provided
 	 */