https://bugs.freedesktop.org/show_bug.cgi?id=90320
--- Comment #10 from Samir Ibradžić sibradzic@gmail.com --- (In reply to N.Leiten from comment #8)
Created attachment 115731 [details] FHD Panel Datasheet.
Due this datasheet the panel looks the same as for DP configuration comparing whith N133HSE-EA1 (asus u38n) panel. So it needs 2 lanes to init video stream.
As for your dmesg, I see problem in dp_aux_ch and training procedure (the voltage and emphasis is 0 which is not right at this point). Need to debug further when I publish my patch and if it not help.
One more thing, do you have FullHD (1920x1080) panel or WHD (1366x768) one. Because on Lenovo site I see Thinkpad e455 base model with WHD. The last one need only 1 DisplayPort lane to work.
Are you saying these may be an issue:
[drm:radeon_dp_aux_transfer_native] dp_aux_ch flags not zero: 00000201 [drm:drm_dp_i2c_do_msg] transaction failed: -5
?