On Mon, Dec 16, 2013 at 11:55 PM, Daniel Drake <drake@xxxxxxxxxxxx> wrote: > On Mon, Dec 16, 2013 at 4:19 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: >> This usually happens if the hpd isn't properly recessed and we start >> the i2c transaction while the physical connection hasn't been >> established properly yet. If you're _really_ slow and careful you can >> probably even break your current delay (presuming this theory is >> correct). > > Hmm yes, I think you are probably right. Without touching the HDMI > cable I disconnect and reconnect the power cable of my TV. Presumably > that plug is more "atomic" :) > > When I do that, it detects the resolution fine. > > Do you have any suggestions on how to fix this then? Anything nicer > than e.g. a 1 second delay before processing hpd events? That would > still fail in the "slow connect" case but might be the best option? Have a bit of logic in the exynos ->detect function to re-try a 2nd round of edid probing after each hdp interrupt if the first one returns an -ENXIO. Only tricky part is to be careful with edge detection so that userspace gets all the hotplug events still. Presuming you don't have any funkiness with reprobing causing yet another hpd interrupt and stuff like that (seen it all), as long as you're using the helpers in drm_crtc_helper.c it should all be working correctly. So you want a work item which just grabs all modeset locks and then calls drm_helper_probe_single_connector_modes or something on the right connector. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
