commit 771a081e44a9baa1991ef011cc453ef425591740 upstream.
In the function alps_is_cs19_trackpoint(), we check if the param[1] is
in the 0x20~0x2f range, but the code we wrote for this checking is not
correct:
(param[1] & 0x20) does not mean param[1] is in the range of 0x20~0x2f,
it also means the param[1] is in the range of 0x30~0x3f, 0x60~0x6f...
Now fix it with a new condition checking ((param[1] & 0xf0) == 0x20).
Fixes: 7e4935ccc323 ("Input: alps - don't handle ALPS cs19 trackpoint-only device")
Cc: stable@vger.kernel.org
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>