Bug 42335 - "EETI eGalax" touchscreen (0eef:a001) registered as touchpad
Summary: "EETI eGalax" touchscreen (0eef:a001) registered as touchpad
Alias: None
Product: xorg
Classification: Unclassified
Component: Input/evdev (show other bugs)
Version: unspecified
Hardware: All Linux (All)
: medium major
Assignee: Peter Hutterer
QA Contact: Xorg Project Team
Depends on:
Reported: 2011-10-28 02:37 UTC by Cedric Sodhi
Modified: 2011-10-29 01:02 UTC (History)
1 user (show)

See Also:
i915 platform:
i915 features:

Xorg.0.log of faulty behaviour (32.60 KB, text/plain)
2011-10-28 02:51 UTC, Cedric Sodhi
no flags Details

Description Cedric Sodhi 2011-10-28 02:37:23 UTC
evdev picks up eGalax 0eef:a001 touchscreen, which is exposed through USB->HID Generic->Event Interface, as a touchpad, which results in the touchscreen being unusuable.

For futher information refer to [1] and [2]. A simple hack has been proposed on Ubuntu Forums [3], which solves the issue in that touchpad capabilities are completely taken out of evdev.

[1] https://sourceforge.net/mailarchive/forum.php?thread_name=20111028085720.GA4696%40fly&forum_name=linuxwacom-devel
[2] http://lists.x.org/archives/xorg-devel/2011-October/026659.html
[3] http://ubuntuforums.org/showpost.php?p=10582067&postcount=9
Comment 1 Cedric Sodhi 2011-10-28 02:51:02 UTC
Created attachment 52847 [details]
Xorg.0.log of faulty behaviour

Note, that not only does EVDEV misinterpret the device as Touchpad, but XOrg also matches it as a Touchpad rather than as a Touchscreen when applying the configuration.
Comment 2 Cedric Sodhi 2011-10-28 02:55:02 UTC
[  5562.153] (II) config/udev: Adding input device eGalax_eMPIA Technology Inc. PCAP MultiTouch Controller (/dev/input/event8)
[  5562.153] (**) eGalax_eMPIA Technology Inc. PCAP MultiTouch Controller: Applying InputClass "evdev touchpad catchall"
[  5562.153] (II) Using input driver 'evdev' for 'eGalax_eMPIA Technology Inc. PCAP MultiTouch Controller'
[  5562.153] (II) Loading /usr/lib/xorg/modules/input/evdev_drv.so
Comment 3 Cedric Sodhi 2011-10-29 01:02:52 UTC
As discussed in the thread on linuxwacom-devel, it turned out that the problem lies in the capabilities which the kernel reports, among which Buttons are defined, mich makes evdev think the pad was a mouse.

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