[xubuntu-users] black screen after resuming from sleep

[Kristian Kourtis]

Dear Group hi,

I'm writing because after upgrading to 18.04, I ran to an isuue which
occours only on Xubuntu or on Ubuntu with xfce4 installed. I have tested
other systems like Korora 26 xfce and also Ubuntu (with Gnome/ Mate/ Kde)
18.04, but none of them produce it, only Xubuntu.
So the problem is that when I suspend the laptop by closing the lid, on
resuming there is only a black screen or first a login screen and after it
become dark. Black means here that there is no backlight at all. I hear
that system has awakened and also I am able to type blindly (and eg. open a
terminal for shutdowning) while backlight remains zero.
I dont know where should be this reported or start to debug it. Have
checked some logfiles but myself didn't find something relevant. I assume
xfce power manager and/or video driver should be analyzed.
My system details below.
Thanks in advance,
Kristian

System:    Host: fordito Kernel: 4.15.0-20-generic x86_64 bits: 64
           Desktop: Xfce 4.12.3 Distro: Ubuntu 18.04 LTS
Machine:   Device: laptop System: Hewlett-Packard product: HP 255 G4
Notebook PC v: Type1ProductConfigId serial: N/A
           Mobo: Hewlett-Packard model: 80CB v: 99.42 serial: N/A
           UEFI: Insyde v: F.1C date: 10/19/2015
CPU:       Quad core AMD A6-6310 APU with AMD Radeon R4 Graphics (-MCP-)
           cache: 2048 KB
           clock speeds: max: 1800 MHz 1: 1951 MHz 2: 2087 MHz 3: 1699 MHz
           4: 1620 MHz
Graphics:  Card: Advanced Micro Devices [AMD/ATI] Mullins [Radeon R4/R5
Graphics]
           Display Server: x11 (X.Org 1.19.6 )
           drivers: ati,radeon (unloaded: modesetting,fbdev,vesa)
           Resolution: 1366x768 at 60.00hz
           OpenGL: renderer: AMD MULLINS (DRM 2.50.0 / 4.15.0-20-generic,
LLVM 6.0.0)
           version: 4.5 Mesa 18.0.0-rc5
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.ubuntu.com/archives/xubuntu-users/attachments/20180513/28b737b4/attachment.html>