<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO - USB Type-C monitor flashes once when play a video file after unplug and re-plug the monitor" href="https://bugs.freedesktop.org/show_bug.cgi?id=110954#c9">Comment # 9</a> on <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO - USB Type-C monitor flashes once when play a video file after unplug and re-plug the monitor" href="https://bugs.freedesktop.org/show_bug.cgi?id=110954">bug 110954</a> from <a class="email" href="mailto:nathan.d.ciobanu@linux.intel.com" title="Nathan Ciobanu <nathan.d.ciobanu@linux.intel.com>"> Nathan Ciobanu</a> <pre>Created <a href="attachment.cgi?id=145081" name="attach_145081" title="dmesg marked with "play audio and flash"">attachment 145081</a> <a href="attachment.cgi?id=145081&action=edit" title="dmesg marked with "play audio and flash"">[details]</a> dmesg marked with "play audio and flash" I took another log on a Chromebook with drm-tip and drm.debug=0xe. I also marked the spot where I start playing the video with "play audio and flash". You'll then see the spurious which get printed during the video playback. [drm:skl_update_scaler] scaler_user index 0.0: staged scaling request for 1920x1080->1724x970 scaler_users = 0x1 [drm:intel_atomic_setup_scalers] Attached scaler id 0.0 to PLANE:31" It is during the video playback time that the flash occurs. The one interesting thing I found is that we restart probing for connectors at this point: [ 3980.917229] [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:86:eDP-1] which is triggered by an ioctl call from user space. For some reason the userspace needs to reprobe and I'm not sure what causes this. Another finding from my previous investigation was that if you wait for the this reprobing to finish and then play the video the flash will not occur.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are on the CC list for the bug.</li> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>