<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [hsw DP-to-DVI] DP hot plug fails if booted without Monitor Attached" href="https://bugs.freedesktop.org/show_bug.cgi?id=85924#c48">Comment # 48</a> on <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [hsw DP-to-DVI] DP hot plug fails if booted without Monitor Attached" href="https://bugs.freedesktop.org/show_bug.cgi?id=85924">bug 85924</a> from <a class="email" href="mailto:tprevite@gmail.com" title="Todd Previte <tprevite@gmail.com>"> Todd Previte</a> <pre>Created <a href="attachment.cgi?id=115935" name="attach_115935" title="Fix for passive DP->DVI/HDMI dongles">attachment 115935</a> <a href="attachment.cgi?id=115935&action=edit" title="Fix for passive DP->DVI/HDMI dongles">[details]</a> <a href='page.cgi?id=splinter.html&bug=85924&attachment=115935'>[review]</a> Fix for passive DP->DVI/HDMI dongles In light of Jean's comments, I looked further into this bug. This problem is related to the fix for <a class="bz_bug_link bz_status_RESOLVED bz_closed" title="RESOLVED FIXED - XRANDR operations very slow unless (phantom) HDMI1 disabled" href="show_bug.cgi?id=41059">bug #41059</a> - the code put in place there stops of the execution of that internal loop which makes a second attempt to probe the DDC. And that's where things go wrong for the DP dongles. This patch supersedes the previous work-around patch I posted. This is a cleaner solution that doesn't require the usleep_range() delays that the higher level function patch did. This patch also preserves (as much as possible) the spirit and intent of the solution for #41059, in that the code shouldn't repeatedly flog a non-existent or unresponsive adapter, thus delaying things unnecessarily. With this patch, a single NAK will be tolerated and the loop will continue. A second NAK happens and it will break out of the loop as it did previously. If you have these passive DP->DVI/HDMI adapters, please test with this patch applied. -T</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> </ul> </body> </html>