Input: of_touchscreen - register multitouch axes

So far, the DT parsing code was only setting up the regular input axes,
completely ignoring their multitouch counter parts.

Fill them with the same parameters than the regular axes.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/of_touchscreen.c

@@ -11,6 +11,7 @@
 
 #include <linux/of.h>
 #include <linux/input.h>
+#include <linux/input/mt.h>
 #include <linux/input/touchscreen.h>
 
 static u32 of_get_optional_u32(struct device_node *np,
@@ -30,6 +31,11 @@ static void touchscreen_set_params(struct input_dev *dev,
 	struct input_absinfo *absinfo;
 
 	if (!test_bit(axis, dev->absbit)) {
+		/*
+		 * Emit a warning only if the axis is not a multitouch
+		 * axis, which might not be set by the driver.
+		 */
+		if (!input_is_mt_axis(axis))
 			dev_warn(&dev->dev,
 				 "DT specifies parameters but the axis is not set up\n");
 		return;
@@ -59,17 +65,23 @@ void touchscreen_parse_of_params(struct input_dev *dev)
 
 	maximum = of_get_optional_u32(np, "touchscreen-size-x");
 	fuzz = of_get_optional_u32(np, "touchscreen-fuzz-x");
-	if (maximum || fuzz)
+	if (maximum || fuzz) {
 		touchscreen_set_params(dev, ABS_X, maximum, fuzz);
+		touchscreen_set_params(dev, ABS_MT_POSITION_X, maximum, fuzz);
+	}
 
 	maximum = of_get_optional_u32(np, "touchscreen-size-y");
 	fuzz = of_get_optional_u32(np, "touchscreen-fuzz-y");
-	if (maximum || fuzz)
+	if (maximum || fuzz) {
 		touchscreen_set_params(dev, ABS_Y, maximum, fuzz);
+		touchscreen_set_params(dev, ABS_MT_POSITION_Y, maximum, fuzz);
+	}
 
 	maximum = of_get_optional_u32(np, "touchscreen-max-pressure");
 	fuzz = of_get_optional_u32(np, "touchscreen-fuzz-pressure");
-	if (maximum || fuzz)
+	if (maximum || fuzz) {
 		touchscreen_set_params(dev, ABS_PRESSURE, maximum, fuzz);
+		touchscreen_set_params(dev, ABS_MT_PRESSURE, maximum, fuzz);
+	}
 }
 EXPORT_SYMBOL(touchscreen_parse_of_params);