[libinput] How I get extra touch events using libinput?

강정현 jhyuni.kang at samsung.com
Tue Jan 5 22:35:49 PST 2016

Dear Peter and guys,

thank you for your information about Andreas Pokorny's patches.
As I checked them out, most of them seem to make sense to me. :)
I have more queries. Would you please kindly answer to me?

How can we send the touch pressure/area events via wayland protocol?
I know this question is something irrelative to libinput. I'd like to get your opinion. :)

Suppose now we have get touch pressure and area events as libinput events and in our wayland server is ready to dealing with them.
When it comes to sending those events (pressure, area) via wayland protocol, as we know, we can't send them because there are no arguments exist in the current latest version of wl_touch_interface.

There can be two or more ways to send the events to wayland client(s).
  - One is extending wayland protocol to have the more arguments.
  - The other is implementing our own wayland extension protocol for our wayland server and clients.
Can you tell me which one is more acceptable to you ? :)

In Andreas Pokorny patch, only support part of standard linux MT protocols except ABS_MT_DISTANCE, ABS_MT_TOOL_TYPE, etc..
Do you have any plan to support whole MT protocol events? Or These events are meaningless to support via libinput?

How can we deal with the additional MT protocol events in libinput, if our kernel support more MT protocol events than the events listed in input.h in libinput ?
Can they be supported ? Do you have any ideas?

Thank you in advance.
JengHyun Kang.

> -----Original Message-----
> From: Peter Hutterer [mailto:peter.hutterer at who-t.net]
> Sent: Tuesday, January 05, 2016 5:46 PM
> Cc: wayland-devel at lists.freedesktop.org; sj76.park at samsung.com;
> duna.oh at samsung.com
> Subject: Re: [libinput] How I get extra touch events using libinput?
> On Tue, Jan 05, 2016 at 05:01:33PM +0900,        wrote:
> > Hello, guys.
> > I have a query regarding linux MT protocol event handling in libinput
> side.
> > I wanted to get the extra events such as ABS_MT_TOUCH_MAJOR,
> > ABS_MT_PRESSURE as an event of libinput, but I found that libinput
> > doesn't handle those events.
> >
> > Thus I'd like to know whether there is any plan regarding ABS_MT_XXX
> > event handling in libinput side.
> > If there are no plan to support those events, how can I handling those
> > events?
> correct, there is currently no handling of these events, but Andreas
> Pokorny has a number of patches to add extra axes for touch events. I
> think this one was the last version:
> http://lists.freedesktop.org/archives/wayland-devel/2015-
> November/025415.html
> and the comments:
> http://lists.freedesktop.org/archives/wayland-devel/2015-
> November/025687.html
> Cheers,
>    Peter

More information about the wayland-devel mailing list