<html>
<head>
<base href="https://bugs.freedesktop.org/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - HID device with many axes is discarded as invalid multitouch device"
href="https://bugs.freedesktop.org/show_bug.cgi?id=82823">82823</a>
</td>
</tr>
<tr>
<th>Assignee</th>
<td>wayland-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Summary</th>
<td>HID device with many axes is discarded as invalid multitouch device
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux (All)
</td>
</tr>
<tr>
<th>Reporter</th>
<td>leo.borisenko@gmail.com
</td>
</tr>
<tr>
<th>Hardware</th>
<td>All
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Component</th>
<td>libinput
</td>
</tr>
<tr>
<th>Product</th>
<td>Wayland
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=104908" name="attach_104908" title="dmesg | grep Microsoft">attachment 104908</a> <a href="attachment.cgi?id=104908&action=edit" title="dmesg | grep Microsoft">[details]</a></span>
dmesg | grep Microsoft
HID device 'USB HID v1.11 Mouse' provided by Microsoft Wireless Optical
Desktop® 2.20 (connected to USB and identified as vendor 0x45e, product
0xe3, version 0x111) is reported as supporting EV_ABS event with ABS_MT_SLOT
code, but nevertheless libevdev_get_num_slots returns -1.
It means that mouse isn't recognized by libinput as a valid device, it's
discarded and doesn't work in Weston.
As partially explained by LKML message [1] (Message-Id [2]):
The root of the problem comes from hid-input, which maps unknown axis
to ABS_MISC. However, when an event code is already in use, hid-input
uses the one after, leading to uses of ABS_MISC + N, where N is the
number of unknown axis.
We are encountering a problem with the multitouch protocol here because
if a device has more than 7 unknown axis (which is the case for the PS3
Sixaxis controller), then the unknown axis get maps to ABS_MT_SLOT and
beyond.
Initial discussion of libinput patch fixing problem for mouse from Wireless
Optical Desktop is at [3].
In my tests with evtest mouse didn't produce any MT_* events.
[1] <a href="https://lkml.org/lkml/2013/11/20/515">https://lkml.org/lkml/2013/11/20/515</a>
[2] <a href="mailto:1384983141-31019-1-git-send-email-benjamin.tissoires@redhat.com">1384983141-31019-1-git-send-email-benjamin.tissoires@redhat.com</a>
[3] <a href="http://lists.freedesktop.org/archives/wayland-devel/2014-August/016603.html">http://lists.freedesktop.org/archives/wayland-devel/2014-August/016603.html</a></pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the assignee for the bug.</li>
</ul>
</body>
</html>