[mythtv-users] Can't start mythfrontend with TV off since moving to Intel graphics

[Jim Abernathy]

On 10/31/20 5:39 AM, Paul Gardiner wrote:
> On 28/10/2020 09:06, James Linder wrote:
>> Paul, late wade in, so excuse any rubbish, and top post because THIS 
>> is thee meat, below may be of interest.
>>
>> All my custom and EDID overide was of no avail to my headless backend.
>> xrandr dis sort out the display issues. IIRC I setup a systemd task 
>> to do it after boot
>> James
>
> Do you remember anything more of this? I tried various uses of xrandr 
> in my .xinitrc file, just before it starts mythfrontend. I'm not sure 
> how to involve systemd: I didn't think xrandr could do anything until 
> the X server is up.
>
> I have a workaround for now: on Gary's advice, I bought an EDID 
> emulator. The EDID it fakes is pretty useless, not even having a 24fps 
> mode, but it does fool the system into thinking a monitor is 
> connected, and I can use the CustomEDID option to get the correct modes.
>
> I'm still interested in other solutions, particularly Mark's thoughts 
> on having mythfrontend handle monitor changes.
>

While I'm not using Intel GFX, I had this issue yesterday. I had not 
tested powering up the system with the TV off and when I did, no 
display. Had to ssh in and reboot with TV on.  So my solution which now 
works is:

1. With TV and computer on and working. I captured the current X11 
information and put it into /etc/X11/xorg.conf. In my case Nvidia has a 
tool for this but so does Xorg.

2. Capture EDID to /etc/X11/hdmi0.edid. I used Nvidia tool, there are 
others.

3. Modify [Device]  section of xorg.conf to include:

     Option         "ConnectedMonitor" "HDMI-0"
     Option         "CustomEDID" "HDMI-0:/etc/X11/hdmi0.edid"
     Option         "IgnoreEDID" "false"
     Option         "UseEDID"    "true"

4. My test that it worked was to issue reboot command and immediately 
turn off TV with TV remote. I check computer with ssh and when it was 
complete up, I turned on TV. I still have to play with input from mouse 
of keyboard to get the display to come alive, but I think that'd because 
I have an 5x1 HDMI switch that will switch away from a port if it's 
powered off and another port is displaying output.

Jim A