Bug 87641

Summary: Displayport MST Support with Club 3d csv 5300 partly working
Product: Drivers Reporter: Stephan Schultchen (stephan.schultchen)
Component: Video(DRI - Intel)Assignee: intel-gfx-bugs (intel-gfx-bugs)
Status: RESOLVED CODE_FIX    
Severity: normal CC: daniel, intel-gfx-bugs, stephan.schultchen
Priority: P1    
Hardware: x86-64   
OS: Linux   
Kernel Version: 3.17.2-031702-generic Subsystem:
Regression: No Bisected commit-id:

Description Stephan Schultchen 2014-11-03 21:16:44 UTC 
hey,

i have a dell xps 13 ultraboock with an integrated intel graphics adapter, a Club 3D Displayport Hub + 2 Displays with displayport.

The recent included support for DP MST is only partly working with the  Club 3D CSV 5300 DP Hub. The two connected displays are only recognised as one display, and both show the same. They are basically working in clone mode.

But it should be possible to operate the hub in extended mode.

While connecting the adapter to the XPS 13 DP port, these error messages can be found in dmesg:

[   64.554887] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.594831] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.634858] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.674876] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.714898] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.754935] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.794970] [drm:intel_dp_set_link_train] *ERROR* DP training pattern 3 not supported
[   64.795191] [drm:intel_dp_complete_link_train] *ERROR* failed to train DP, aborting



if further information is needed, please let me know.

sincerly

stephan
Comment 1 Jani Nikula 2014-11-04 07:50:29 UTC 
The error messages are presumed fixed in v3.18-rc3 by

commit 7809a61176b385ebb3299ea43c58b1bb31ffb8c0
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Wed Oct 29 11:03:26 2014 +0200

    drm/i915/dp: only use training pattern 3 on platforms that support it

Please reopen if you have other problems or the problem persists with v3.18-rc3 or later.
Comment 2 Stephan Schultchen 2014-11-04 17:48:49 UTC 
i tried the 3.18.rc3 kernel from http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.18-rc3-vivid/.

the error messages from above are now gone, but now i have this in dmesg:

[  113.968647] [drm:intel_dp_aux_ch] *ERROR* dp_aux_ch receive error status 0x6225003f

besides this, the hub is still only working in clone mode, and xrandr sees only one display, but still, two are connected.
Comment 3 Daniel Vetter 2014-11-26 16:16:50 UTC 
To keep the bug entries sane, can you please file a new one and link to this one here? Thanks, Daniel