Hi,
On 10/7/20 1:35 PM, Bastien Nocera wrote:
On Wed, 2020-10-07 at 11:51 +0200, Hans de Goede wrote:
<snip>
Dmitry, any existing stuff like this in input?
There already is a SW_FRONT_PROXIMITY defined in
input-event-codes.h, which I guess means detection if
someone is sitting in front of the screen. So we could add:
SW_LAP_PROXIMITY
SW_PALMREST_PROXIMITY,
And then we have a pretty decent API for this I think.
From the point of view of writing the consumer code for this API, it's
rather a lot of pain to open the device node (hoping that it's the
right one for what we need), getting the initial state, setting up
masks to avoid being woken up for every little event, and parsing those
events.
There is not much difference with the iio sysfs API though, you would
also need to iterate over all the iio devices and test if they
are a proximity sensor (and read the new location sysfs file discussed).
Where would the necessary bits of metadata for daemons to be able to
find that those switches need to get added?
evdev files export info on which events they can report. Not only
the types of events (EV_SW in this case) but also a bitmask for
which event-codes they can report within that type.
If you go down that route, you'll definitely want a want to attach the
"palmrest" to the touchpad/keyboard that it corresponds to, otherwise
that might have weird interactions when using external keyboards and
touchpads. (I don't know what you'd use that proximity sensor for
though)
The proximity sensor is primarily for deciding how strong a signal
wireless devices inside the laptop may emit.
Regards,
Hans
