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authorMathias Gottschlag <mgottschlag@gmail.com>2015-03-07 13:27:08 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2015-03-07 13:40:20 -0800
commit679d83ea9390636ded518f533af0cefbade317c7 (patch)
tree2d0a85cfb4a397773f63f4b24d5052984c9c7b84 /drivers
parent3e9845251926723319fb60c9e546fe42d3d11687 (diff)
downloadkernel-679d83ea9390636ded518f533af0cefbade317c7.tar.gz
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 <mgottschlag@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/input/mouse/focaltech.c12
1 files changed, 10 insertions, 2 deletions
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);