Input: uinput - allow for 0/0 min/max on absolute axes.

Some devices provide absolute axes with min/max of 0/0 (e.g. wacom's
ABS_MISC axis). Current uinput restrictions do not allow duplication of
these devices and require hacks in userspace to work around this.

If the kernel accepts physical devices with a min/max of 0/0, uinput
shouldn't disallow the same range.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 364bdf4..7360568 100644 (file)
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -302,10 +302,14 @@ static int uinput_validate_absbits(struct input_dev *dev)
        int retval = 0;
 
        for (cnt = 0; cnt < ABS_CNT; cnt++) {
+               int min, max;
                if (!test_bit(cnt, dev->absbit))
                        continue;
 
-               if (input_abs_get_max(dev, cnt) <= input_abs_get_min(dev, cnt)) {
+               min = input_abs_get_min(dev, cnt);
+               max = input_abs_get_max(dev, cnt);
+
+               if ((min != 0 || max != 0) && max <= min) {
                        printk(KERN_DEBUG
                                "%s: invalid abs[%02x] min:%d max:%d\n",
                                UINPUT_NAME, cnt,