"EDID Invalid" On Xubuntu 16.04

[mlukaszek]

Thanks, I've raised this internally for analysis.

Cheers,
Michal

[TomStaels]

having the same issue...
any solution to this yet ?

[   49.032846] usb 2-1.1: new high-speed USB device number 3 using ehci-pci
[   49.128660] usb 2-1.1: New USB device found, idVendor=17e9, idProduct=0033
[   49.128672] usb 2-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   49.128677] usb 2-1.1: Product: K33907
[   49.128682] usb 2-1.1: Manufacturer: DisplayLink
[   49.128686] usb 2-1.1: SerialNumber: 0033-100831
[   50.148085] [drm] vendor descriptor length:e0 data:00 00 00 00 00 00 00 00 00 00 00
[   50.148095] [drm:udl_driver_load [udl]] *ERROR* Unrecognized vendor firmware descriptor
[   50.196976] EDID block is all zeroes
[   50.196991] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[   50.197561] udl 2-1.1:1.0: fb1: udldrmfb frame buffer device
[   50.197564] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[   50.197564] [drm] No driver support for vblank timestamp query.
[   50.197566] [drm] Initialized udl on minor 1
[   50.197591] usbcore: registered new interface driver udl
[   50.390848] EDID block is all zeroes
[   50.390864] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[   50.438966] EDID block is all zeroes
[   50.438977] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  120.941994] EDID block is all zeroes
[  120.942011] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  121.081365] EDID block is all zeroes
[  121.081383] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  306.286639] EDID block is all zeroes
[  306.286655] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  758.287223] EDID block is all zeroes
[  758.287230] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  758.364453] EDID block is all zeroes
[  758.364460] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  758.441228] EDID block is all zeroes
[  758.441235] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  758.459631] evdi: module verification failed: signature and/or required key missing - tainting kernel
[  758.461167] evdi: [I] Initialising logging on level 5
[  759.439734] EDID block is all zeroes
[  759.439761] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  759.488616] EDID block is all zeroes
[  759.488628] udl 2-1.1:1.0: DVI-I-1: EDID invalid.

[mlukaszek]

Don't use udl and evdi together. For devices requiring evdi, make sure udl is blacklisted. For USB 2.0 devices using DL-1xx chips, stick to udl, and don't install evdi.

Cheers,
Michal

[TomStaels]

Thanks for helping out Michal!

uninstalled evdi
un-blacklisted udlfb
screen works, but can't set native resolution (1280x1024), only options are 800x600 and 1024x768

help?

[mlukaszek]

DRM driver for USB 2.0 DisplayLink Devices is udl, a rewrite of the original udlfb driver (which you shouldn't use). Which one have you unblacklisted?

Thanks,
Michla

[TomStaels]

i was trying to get it to work with udlfb, since this seems to be a "Bad Idea" (tm), I tried udl :

$ lsmod | grep "udl"
udl                    32768  1
drm_kms_helper        147456  2 udl,i915
drm                   364544  7 udl,i915,drm_kms_helper

Turning ON the "Unknown Display" in Displays, the system becomes nearly unresponsive, and the display never actually turns on.
syslog is spammed with :

[  104.344500] [drm] wait for urb interrupted: ffffffc2 available: 0
[  105.344655] [drm] wait for urb interrupted: ffffffc2 available: 0
[  106.344680] [drm] wait for urb interrupted: ffffffc2 available: 0
[  107.356719] [drm] wait for urb interrupted: ffffffc2 available: 0
[  107.456677] EDID block is all zeroes
[  107.456687] udl 2-1.1:1.0: DVI-I-1: EDID invalid.
[  108.564776] [drm] wait for urb interrupted: ffffffc2 available: 0
[  109.656798] [drm] wait for urb interrupted: ffffffc2 available: 0
[  110.696848] [drm] wait for urb interrupted: ffffffc2 available: 0
[  111.712881] [drm] wait for urb interrupted: ffffffc2 available: 0
[  112.728887] [drm] wait for urb interrupted: ffffffc2 available: 0
[  113.748959] [drm] wait for urb interrupted: ffffffc2 available: 0
[  114.776999] [drm] wait for urb interrupted: ffffffc2 available: 0
[  115.797050] [drm] wait for urb interrupted: ffffffc2 available: 0
[  116.817072] [drm] wait for urb interrupted: ffffffc2 available: 0
[  117.837127] [drm] wait for urb interrupted: ffffffc2 available: 0
[  118.857171] [drm] wait for urb interrupted: ffffffc2 available: 0
[  119.873186] [drm] wait for urb interrupted: ffffffc2 available: 0
[  120.893225] [drm] wait for urb interrupted: ffffffc2 available: 0
[  121.925288] [drm] wait for urb interrupted: ffffffc2 available: 0
[  122.945319] [drm] wait for urb interrupted: ffffffc2 available: 0
[  123.973343] [drm] wait for urb interrupted: ffffffc2 available: 0
[  124.431887] EDID block is all zeroes
[  124.431904] udl 2-1.1:1.0: DVI-I-1: EDID invalid.

[mlukaszek]

This looks like a genuine problem with finding out what the EDID for the monitor is. Note the messages telling that the block is all zeros. How is the monitor connected to the device? Do you use an adapter (DVI-VGA) - some of them could block lines reponsible for EDID read?

Thanks,
Michal