Input: appletouch - fix integer overflow issue
Input: appletouch - fix integer overflow issue

When reading data from Geyser 2 touchpads used on post Oct 2005 Apple
PowerBooks the driver was casting X and Y coordinates values to
'signed char'. Testing on one of such PowerBooks I have noticed that
touchpad always generates positive values, but some of them are greater
that 127, and thus, when cast to 'signed char' being interpreted as
a negative.

Such bigger values have been observed infrequently, closer to the
edges of a touchpad, so the problem was not very visible.
Nevertheless, the patch would potentially improve touchpad
driver accuracy.

Signed-off-by: Vadim Zaliva <0cb26e2242f1e2f5cbbc8204af141dee67d5fa79@crocodile.org>
Signed-off-by: Dmitry Torokhov <10a8c465cefc9bdd6c925e26964d23c90f1141cc@mail.ru>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs