Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Sysfs entry for reading and setting of the polling interval. If the
interval is set to 0, polling is stopped. Polling is restarted when
interval is changed to non-zero.

sysfs entries:
poll = current polling interval in msec (RW)
max = max allowed polling interval (RO)
min = min allowed polling interval (RO)

Minimum and maximum limit for interval can be set while setting up the
device.

Interval can be adjusted even if the input device is not currently open.

[dtor@mail.ru: add kernel doc markup for the new fields]
Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Optional open and close methods for preparing and closing
the device.
Signed-off-by: NSamu Onkalo <samu.p.onkalo@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

input-polldev provides a skeleton for supporting simple input
devices that need to be periodically scanned or polled to
detect changes in their state.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>