From: Mathias Gottschlag Date: Sat, 7 Mar 2015 21:27:08 +0000 (-0800) Subject: Input: psmouse - ensure that focaltech reports consistent coordinates X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=679d83ea9390636ded518f533af0cefbade317c7;p=linux-beck.git Input: psmouse - ensure that focaltech reports consistent coordinates We don't know whether x_max or y_max really hold the maximum possible coordinates, and we don't know for sure whether we correctly interpret the coordinates sent by the touchpad, so we clamp the reported values to prevent confusion in userspace code. Signed-off-by: Mathias Gottschlag Signed-off-by: Dmitry Torokhov --- diff --git a/drivers/input/mouse/focaltech.c b/drivers/input/mouse/focaltech.c index e8fafe8785a7..c66e0e04bb7e 100644 --- a/drivers/input/mouse/focaltech.c +++ b/drivers/input/mouse/focaltech.c @@ -126,9 +126,17 @@ static void focaltech_report_state(struct psmouse *psmouse) input_mt_slot(dev, i); input_mt_report_slot_state(dev, MT_TOOL_FINGER, active); if (active) { - input_report_abs(dev, ABS_MT_POSITION_X, finger->x); + unsigned int clamped_x, clamped_y; + /* + * The touchpad might report invalid data, so we clamp + * the resulting values so that we do not confuse + * userspace. + */ + clamped_x = clamp(finger->x, 0U, priv->x_max); + clamped_y = clamp(finger->y, 0U, priv->y_max); + input_report_abs(dev, ABS_MT_POSITION_X, clamped_x); input_report_abs(dev, ABS_MT_POSITION_Y, - priv->y_max - finger->y); + priv->y_max - clamped_y); } } input_mt_report_pointer_emulation(dev, true);