Query last reported event state

[Daniel Mack <daniel@caiaq.de>]

Hi,

is there a way to query the last state an input device reported,
preferably even for a special key mask? When a button is pressed and a
userspace application is started, it should be able to figure out the
current state, especially because those GPIO signals are likely
connected to other peripherals to report arbitrary events in the system.
Is there any such framework for that purpose?

A somewhat related topic is: Looking at the gpio_keys.c for example, I
think there should be code that reports an event from probe() when the
configured GPIO is not in its 'inactive' state, otherwise it will loose
the first key-up event, right?

Thanks,
Daniel