Bug 79071

Summary:	Export touchscreen size to X clients
Product:	xorg	Reporter:	Bastien Nocera <bugzilla>
Component:	Input/evdev	Assignee:	Peter Hutterer <peter.hutterer>
Status:	RESOLVED NOTABUG	QA Contact:	Xorg Project Team <xorg-team>
Severity:	normal
Priority:	medium	CC:	peter.hutterer
Version:	unspecified
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:

Description Bastien Nocera 2014-05-22 14:52:16 UTC

Touchscreens usually have in their report descriptors information about the physical size of the touchscreen they're attached to. For example, it would be possible to see that a touchscreen was 23" big, so gnome-settings-daemon could automatically match it with the 23" display that's configured.

That information is currently not exported to X clients, so gnome-settings-daemon cannot consume it.

Comment 1 Peter Hutterer 2014-05-22 22:06:17 UTC

the XI valuator class structs have the range and the resolution in units/m, that should give you the physical size (where the device doesn't lie about it). Is this good enough?

http://cgit.freedesktop.org/xorg/proto/inputproto/tree/specs/XI2proto.txt#n985

Comment 2 Bastien Nocera 2014-05-23 07:21:52 UTC

Benjamin Tissoires pointed this out, and yes, it's good enough for us to use even if the way that it's exported is slightly more convoluted than I would have expected.

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.