Input: hgpk - detect simple mode overflows

Based on work by Paul Fox.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/input/mouse/hgpk.c b/drivers/input/mouse/hgpk.c
index b54f074ec307..7f6cb32d177a 100644
--- a/drivers/input/mouse/hgpk.c
+++ b/drivers/input/mouse/hgpk.c
@@ -431,6 +431,11 @@ static void hgpk_process_simple_packet(struct psmouse *psmouse)
         int x = packet[1] - ((packet[0] << 4) & 0x100);
         int y = ((packet[0] << 3) & 0x100) - packet[2];
 
+        if (packet[0] & 0xc0)
+                hgpk_dbg(psmouse,
+                         "overflow -- 0x%02x 0x%02x 0x%02x\n",
+                         packet[0], packet[1], packet[2]);
+
         if (hgpk_discard_decay_hack(psmouse, x, y)) {
                 if (tpdebug)
                         hgpk_dbg(psmouse, "discarding\n");