<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - 4k MST monitor doesn't come back from "xset dpms force off": failed link training" href="https://bugs.freedesktop.org/show_bug.cgi?id=89453#c10">Comment # 10</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - 4k MST monitor doesn't come back from "xset dpms force off": failed link training" href="https://bugs.freedesktop.org/show_bug.cgi?id=89453">bug 89453</a> from <a class="email" href="mailto:palmer@dabbelt.com" title="Palmer Dabbelt <palmer@dabbelt.com>"> Palmer Dabbelt</a> <pre>I've been trying to play around a bit to see if I could get any more information, as I'm afraid those logs aren't useful at all. Here's what I found: * My monitor (Asus PB287Q) has two modes, listed as "DisplayPort 1.1 Steam" and "DisplayPort 1.2 Stream". The monitor only supports 4k@60Hz when on DP1.2, which is what I've been using. I believe this means the monitor is not actually a MST monitor, but I'm not sure as I don't know much about this stuff. * When I set the monitor to "DisplayPort 1.1 Stream" it defaults to 1080p@60Hz, but I still get similar behavior -- the monitor works fine before that MST related commit, and is broken afterwards. * In addition to not coming back from DPMS off, the monitor doesn't hotplug. There aren't any errors in dmesg when it fails to come up this way. * Everything appears to work fine (both before and after the MST commit) when I use a Dell 2408WFPb, which I assume is a DP1.1-only monitor (it's manufacture date is listed as August 26th, 2009, which I believe predates the DP1.2 standard). * linux-4.0-rc3 exhibits the same behavior as 3.17. Are there are any more useful debug logs I can produce?</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>