[Openchrome-devel] [Bug 91966] No signal to monitor with X and openchrome using VX855 chipset graphics

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=91966

--- Comment #97 from Kevin Brace <kevinbrace at gmx.com> ---
(In reply to Christopher from comment #96)

Hi Christopher,

> 'ey, Kevin -- take all the time you need. I don't rush people when they're
> tryin' to help me ;)
> 
> Do your thing. I'll be here when you got somethin' for me.

I spent a few hours analyzing one of the log file you attached.
The one I looked at specifically was the current compiled version of OpenChrome
Xorg.0.log (See Xorg.0.log from Git-built driver).
I find these messages curious.

_________________________________________________________________________
. . .
[    72.614] (II) Loading sub module "ddc"
[    72.614] (II) LoadModule: "ddc"
[    72.614] (II) Module "ddc" already built-in
[    72.614] (II) CHROME(0): ViaOutputsDetect
[    72.614] (==) CHROME(0): LVDS-0 : Digital output bus width is 12 bits.
[    72.614] (==) CHROME(0): LVDS-0 : DVI Center is disabled.
[    72.614] (==) CHROME(0): LVDS Panel will not be forced.
[    72.614] (==) CHROME(0): Panel size is not selected from config file.
[    72.615] (II) CHROME(0): Output VGA-1 using monitor section Monitor0
[    72.615] (**) CHROME(0): Option "PreferredMode" "1280x1024"
[    72.616] (II) CHROME(0): I2C device "I2C bus 1:ddc2" registered at address
0xA0.
[    72.623] (--) CHROME(0): Test for CRT with VSYNC
[    72.623] (II) CHROME(0): EDID for output VGA-1
[    72.624] (II) CHROME(0): Output VGA-1 disconnected
[    72.624] (WW) CHROME(0): No outputs definitely connected, trying again...
[    72.624] (II) CHROME(0): Output VGA-1 disconnected
[    72.624] (WW) CHROME(0): Unable to find connected outputs - setting
1024x768 initial framebuffer
[    72.624] (II) CHROME(0): Using default gamma of (1.0, 1.0, 1.0) unless
otherwise stated.
[    72.624] (==) CHROME(0): DPI set to (96, 96)
. . .
_________________________________________________________________________

I think DDX (Device Dependent X == OpenChrome in this case) is not seeing a
monitor when it tries to sense the presence of a VGA monitor via DDC (I2C).
Hence, when the OS gives up the booting, it gives the following error message
(See xerrs.log from Git-built driver).

_________________________________________________________________________
. . .
(EE) Server terminated successfully (0). Closing log file.
xwininfo: error: unable to open display ":0"
xwininfo: error: unable to open display ":0"
/usr/bin/xinit: connection to X server lost
XIO:  fatal IO error 2 (No such file or directory) on X server ":0"
_________________________________________________________________________

The question I now have is, why isn't DDX not seeing the VGA monitor?
It appears that DDC related code is located inside xorg, and is not directly
handled by OpenChrome.
    Although I do not wish to suggest a new "wild goose chase" type of an idea,
if you happened to have a different VGA cable, maybe you can try it.
Also, you can also try a DVI cable instead of VGA cable + DVI to VGA dongle
combination to see what happens.
Last time I checked, your Wyse thin client has a DVI output port, not VGA
output port coming out of it.
I personally think it will make no difference, but I will like to see what
happens when you try a DVI cable.
    Just for your information, I have spent some time trying to figure out what
OpenChrome does when it initialize itself.
I now have somewhat better understanding of the code, hence, I was able to
suggest this likely cause of why it does not work correctly with your
particular hardware.
I will be off for at least a day due to air travel.

Regards,

Kevin Brace

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/openchrome-devel/attachments/20151226/d8eda626/attachment.html>