options udlfb fb_defio=1

Thanks for the prompt. I’ve updated the post with some more recent information. In your case (running fbdev, just getting a black screen), it’s likely you just need to enable udlfb’s fb_defio option (per the link above).

Thanks,
Bernie

I see that this post was made back in 2010, so I realize that I’m a little late to the party. Anyhow, looks like you committed to udlfb 12 days ago, so I imagine the project is still under active development.

My question is about the install process for udlfb. I have a Mimo 7″ usb monitor that I have working sans rotation in Ubuntu 11.04 with the DisplayLink driver. I cloned udlfb and ran “make && sudo make install”, but after switching my xorg.conf to use {Driver “fbdev”} I couldn’t get anything on the monitor, with or without the rotation option. Can you give me any advice on places I should be looking to troubleshoot this?

Thanks very much
-Brad

Thanks for this great posting! It really helped to find the exact problem I’m having on a Google search.

Any update on the defio/udlfb vertical line issue?

Chris

Unfortunately, I don’t have an answer on this one, as none of my devices has touchscreen going. It may be a xf86-video-fbdev limitation, you might want to ask around ..

Best wishes,
Bernie

Please allow one more question about a strange effect:

I am trying to use a touchscreen display via a dislaylink adapter, using the evtouch-driver (http://www.conan.de/touchscreen/evtouch.html) for the touch-feature. Without any rotation everything works fine, but as soon as I rotate the display – which works fine – the X-server dies as soon as the touchscreen is actually touched. The log says ‘EVTouch TouchScreen: Unable to grab device (Device or resource busy).’, and the server dies with signal 11.

The only thing I changed is to include the rotate-option in the device-section of the screen.

Do you have any idea or workaround ?

Thank you very much, best regards !
Jens

Yep, those lines are a problem with the defio mechanism (and/or how udlfb is using it). See http://lists.freedesktop.org/archives/libdlo/2010-January/000533.html for more background. I’ve been exchanging emails with the author of the defio mechanism, and hopefully the root cause and solution will be found soon.

Best wishes,
bernie

got a display link device to work in portrait mode.

With the display not rotated there are no errors, if I use the rotate option there are random vertical lines that appear to be frozen and do not update any more. These lines only disappear on a restart of X.

I tried disabling ShadowFB (is it even used???) with no difference.

Any idea on how to fix this or is it due to the beta character of udlfb?

Thanks for your work, Regards

Jens Seekamp