sna: (Haswell) X-server freezes when enabling DP at docking station
Related bug report: https://bugs.freedesktop.org/show_bug.cgi?id=71267
The freezing is removed by upgrading the firmware of the dock to v2.17, although the update is designed to fix the flickering problems and not to address our particular issue (http://support.lenovo.com/en_US/detail.page?DocID=HT081248).
(1) It is discussed that the system should not freeze even with a buggy dock, so there probably will be a fix allowing to use docks with the original firmware. That again should meet the requirements of most sponsors. A fix is already discussed in the bug report.
(2) Using more than one monitor at a time connected to the dock is still not possible. The dock employs a Synaptics VMM2322 Display Port HUB, as indicated by the README file of the dock firmware update (http://download.lenovo.com/ibmdl/pub/pc/pccbbs/options/fwdphb01.txt). Supporting this is a completely different issue: Multi Stream Transport must be supported, which currently is not. Join me at http://freedomsponsors.org/core/issue/444/hsw-mst-dell-dock-dvi-knocks-out-dp-when-unplugged if you like to sponsor someone who does implement this.
Since this was fixed by the dock firmware update from Lenovo I'm removing my offer and adding it to the issue related to multi monitor support.
I can confirm that the latest firmware update (2.17) from Lenovo resolves the freezing issue (t440s + ultradock).
latest firmware update (2.17) from Lenovo resolves the freezing issue
Updated Lenovo Dock-Firmware 2.17 fixes the issue for me.
As the issue is fixed and the person doing so kindly declined our offer, I'd like to revoke to be able to fund other great stuff.
Thanks for fixing!
As others have noted, this issue was fixed with a firmware update, and the developer of the fix that works around the buggy firmware declined compensation as he is employed to do this.
I will take this bounty and donate it to a few opensource projects such as ArchLinux, so that this money is put to good use by others.
Thanks for everyone's work on this. Now lets hope Intel and others can get DP Multi-Stream Transport support into Linux so we can have multiple monitors plugged into our docks.
Revoke, since firmware update from Lenovo resolves the freezing issue
As others have noted, this is solved by a firmware upgrade.
Now, the main reason I want to use a dock is multi-monitor support, so I'll move the offer to http://freedomsponsors.org/core/issue/444/hsw-mst-dell-dock-dvi-knocks-out-dp-when-unplugged
Was fixed with a firmware update by lenovo.
FreedomSponsors will charge a 3% fee on top of your payment. For offers in US$, Paypal's fees will also apply.