I am currently stuck analyzing this issue. The following considerations refer to commit dbd76eb58bd9d7a55de753daa5572ef24867d924.
After adding lots of debug output to displays.c, I noticed a potential issue in static GPtrArray* xfce_displays_helper_list_outputs (XfceDisplaysHelper*) which contains the line of if (output_info->connection != RR_Connected) When powering off a screen and powering it on again, the value of output_info->connection is always 1 (=RR_Disconnected). Hence, the rest of the surrounding loop's iteration is skipped, no modes are detected, etc. According to my current understanding (which might be completely erroneous) of how the code works, this is wrong and it could hint to the actual cause of the issue - which I'm still unable to identify. Further observations: xfce_displays_helper_list_outputs is called twice in displays.c - once by xfce_displays_helper_init(...) and once by xfce_displays_helper_reload(...). In the former case, (output_info->connection != RR_Connected) is false for one of my outputs, thus modes are getting detected, etc. In the latter, it is not. Can anybody assess whether or not I am on the right track? Any help debugging this would still be greatly appreciated. :) -- You received this bug notification because you are a member of UBUNTU - AL - BR, which is subscribed to Mythbuntu. https://bugs.launchpad.net/bugs/1308105 Title: Xfce resets TV mode to NULL when power cycled Status in Mythbuntu, Ubuntu derivative focused upon MythTV: Confirmed Status in xfce4-settings: Confirmed Status in “nvidia-graphics-drivers” package in Ubuntu: Invalid Status in “nvidia-graphics-drivers-331” package in Ubuntu: Invalid Status in “xfce4-settings” package in Ubuntu: Confirmed Bug description: I had an HTPC with Mythbuntu 12.04 installed. Upon upgrading a new behavior that if the TV is power cycled it no longer detects a link with the HTPC. When this happens I can find in the xorg log that there is an accompanying log item: [ 39829.509] (II) NVIDIA(0): Setting mode "NULL" After debugging with NVIDIA at https://devtalk.nvidia.com/default/topic/729955/linux/tv-stops-being- detected/ we've deteremined it's a X client that reacts to the RANDR events causing the mode to be set to NULL. Working through the list in an Xfce environment, the culprit is xfsettingsd. If xfsettingsd is running, it causes the TV to come up in a NULL mode. If it's killed, it remains in the mode it was previously running in. Until this is fixed, this behavior can be worked around with a simple shell script: ============================== #!/bin/sh #Fix TV state when HDMI link is lost. #By Mario Limonciello <[email protected]> OUTPUT="HDMI-0" BAD_MODE="1280x720" GOOD_MODE="1920x1080" for MODE in $BAD_MODE $GOOD_MODE; do DISPLAY=:0 xrandr --output $OUTPUT --mode $MODE sleep 2 done ============================== To manage notifications about this bug go to: https://bugs.launchpad.net/mythbuntu/+bug/1308105/+subscriptions -- Mailing list: https://launchpad.net/~linux-traipu Post to : [email protected] Unsubscribe : https://launchpad.net/~linux-traipu More help : https://help.launchpad.net/ListHelp

