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      <base href="https://bugs.freedesktop.org/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - DVI display on DisplayPort-MST behind DP-DVI converter gets no EDID"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=91614">91614</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>DVI display on DisplayPort-MST behind DP-DVI converter gets no EDID
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>DRI
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>x86-64 (AMD64)
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux (All)
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>DRM/Intel
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>cweiske@cweiske.de
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=117641" name="attach_117641" title="dmesg with drm.debug=14">attachment 117641</a> <a href="attachment.cgi?id=117641&action=edit" title="dmesg with drm.debug=14">[details]</a></span>
dmesg with drm.debug=14

My setup: Thinkpad T440p with an Ultra Dock, two identical displays connected
to the dock. DP2-1 connected via a DP-DVI converter to the docks' display port
socket, DP2-2 connected directly to the dock's DVI port.

DP2-1 gets the wrong resolution; "xrandr --verbose" shows that no EDID data are
available. I can manually add the correct resolution with "xrandr --addmode",
which makes the display work on the correct resolution.

I can swap the displays physically, and the one connected to the DVI port
always gets the correct resolution - so it is not a display issue.

I connected the display via a MiniDP-DVI adapter directly to the laptop
(bypassing the docking station) and it got the correct resolution.


Attached is dmesg output with drm.debug=14


Xorg server: 1:7.7+1ubuntu8.1
xf86-video-intel: git 2015-07-31 17:17,
bc063c9f4af90542297877281b1b9f4692dafde4
Linux kernel: Linux csystems 4.1.4-dp-mst #1 SMP Fri Aug 7 09:25:36 CEST 2015
x86_64 x86_64 x86_64 GNU/Linux</pre>
        </div>
      </p>
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