Input: ili210x - fetch touchscreen geometry from DT

Fetching the geometry from the ILI251x registers seems unreliable and
sometimes returns all zeroes. Add support for fetching the geometry and
axis inversion from DT instead.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/ili210x.c

@@ -4,6 +4,7 @@
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
 #include <linux/delay.h>
 #include <linux/workqueue.h>
 #include <linux/gpio/consumer.h>
@@ -20,15 +21,6 @@
 #define REG_FIRMWARE_VERSION	0x40
 #define REG_CALIBRATE		0xcc
 
-struct panel_info {
-	u8 x_low;
-	u8 x_high;
-	u8 y_low;
-	u8 y_high;
-	u8 xchannel_num;
-	u8 ychannel_num;
-} __packed;
-
 struct firmware_version {
 	u8 id;
 	u8 major;
@@ -46,6 +38,7 @@ struct ili210x {
 	unsigned int poll_period;
 	struct delayed_work dwork;
 	struct gpio_desc *reset_gpio;
+	struct touchscreen_properties prop;
 	enum ili2xxx_model model;
 	unsigned int max_touches;
 };
@@ -149,8 +142,6 @@ static bool ili210x_report_events(struct ili210x *priv, u8 *touchdata)
 	unsigned int x = 0, y = 0;
 
 	for (i = 0; i < priv->max_touches; i++) {
-		input_mt_slot(input, i);
-
 		if (priv->model == MODEL_ILI210X) {
 			touch = ili210x_touchdata_to_coords(priv, touchdata,
 							    i, &x, &y);
@@ -161,11 +152,12 @@ static bool ili210x_report_events(struct ili210x *priv, u8 *touchdata)
 				contact = true;
 		}
 
+		input_mt_slot(input, i);
 		input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
-		if (touch) {
-			input_report_abs(input, ABS_MT_POSITION_X, x);
-			input_report_abs(input, ABS_MT_POSITION_Y, y);
-		}
+		if (!touch)
+			continue;
+		touchscreen_report_pos(input, &priv->prop, x, y,
+				       true);
 	}
 
 	input_mt_report_pointer_emulation(input, false);
@@ -274,10 +266,8 @@ static int ili210x_i2c_probe(struct i2c_client *client,
 	struct ili210x *priv;
 	struct gpio_desc *reset_gpio;
 	struct input_dev *input;
-	struct panel_info panel;
 	struct firmware_version firmware;
 	enum ili2xxx_model model;
-	int xmax, ymax;
 	int error;
 
 	model = (enum ili2xxx_model)id->driver_data;
@@ -334,35 +324,16 @@ static int ili210x_i2c_probe(struct i2c_client *client,
 		return error;
 	}
 
-	/* get panel info */
-	error = ili210x_read_reg(client, REG_PANEL_INFO, &panel, sizeof(panel));
-	if (error) {
-		dev_err(dev, "Failed to get panel information, err: %d\n",
-			error);
-		return error;
-	}
-
-	xmax = panel.x_low | (panel.x_high << 8);
-	ymax = panel.y_low | (panel.y_high << 8);
-
 	/* Setup input device */
 	input->name = "ILI210x Touchscreen";
 	input->id.bustype = BUS_I2C;
 	input->dev.parent = dev;
 
-	__set_bit(EV_SYN, input->evbit);
-	__set_bit(EV_KEY, input->evbit);
-	__set_bit(EV_ABS, input->evbit);
-	__set_bit(BTN_TOUCH, input->keybit);
-
-	/* Single touch */
-	input_set_abs_params(input, ABS_X, 0, xmax, 0, 0);
-	input_set_abs_params(input, ABS_Y, 0, ymax, 0, 0);
-
 	/* Multi touch */
-	input_mt_init_slots(input, priv->max_touches, 0);
-	input_set_abs_params(input, ABS_MT_POSITION_X, 0, xmax, 0, 0);
-	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ymax, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, 0xffff, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 0xffff, 0, 0);
+	touchscreen_parse_properties(input, true, &priv->prop);
+	input_mt_init_slots(input, priv->max_touches, INPUT_MT_DIRECT);
 
 	error = devm_add_action(dev, ili210x_cancel_work, priv);
 	if (error)