[PATCH 4.19 60/98] HID: wacom: Correct distance scale for 2nd-gen Intuos devices

[Greg Kroah-Hartman]

From: Jason Gerecke <jason.gerecke@xxxxxxxxx>

commit b72fb1dcd2ea9d29417711cb302cef3006fa8d5a upstream.

Distance values reported by 2nd-gen Intuos tablets are on an inverted
scale (0 == far, 63 == near). We need to change them over to a normal
scale before reporting to userspace or else userspace drivers and
applications can get confused.

Ref: https://github.com/linuxwacom/input-wacom/issues/98
Fixes: eda01dab53 ("HID: wacom: Add four new Intuos devices")
Signed-off-by: Jason Gerecke <jason.gerecke@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.4+
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/hid/wacom_wac.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -848,6 +848,8 @@ static int wacom_intuos_general(struct w
 		y >>= 1;
 		distance >>= 1;
 	}
+	if (features->type == INTUOSHT2)
+		distance = features->distance_max - distance;
 	input_report_abs(input, ABS_X, x);
 	input_report_abs(input, ABS_Y, y);
 	input_report_abs(input, ABS_DISTANCE, distance);