USB2VGA2 device not autodetected at boot

[Bryce Harrington]

Binary package hint: xserver-xorg-video-sisusb

[Problem]
The USB2VGA2 device from StarTech.com works when manually configured but does not automatically detect when X boots.

[Configuration]
Manual configuration requires adding a section like this in xorg.conf:

Section "Device"
        Identifier "SiS USB2VGA"
        VendorName "SiS" # Value does not matter
        BoardName "SiS" # Value does not matter

        Driver "sisusb"

# BusID: Does not matter if you have only one USB2VGA dongle.
# If you have more than one, you can specify the device node
# name or the device number here.
        #BusID "USB:/dev/sisusbvga0"

EndSection

Section "Screen"
        Identifier "screen1"
        Device "SiS USB2VGA"
        Monitor "Generic"
        DefaultDepth 16
        SubSection "Display"
                Depth 16
                Modes "1600x1200" "1024x768" "800x600" "640x480"
        EndSubSection
        SubSection "Display"
                Depth 8
                Modes "1600x1200" "1024x768" "800x600" "640x480"
        EndSubSection
        SubSection "Display"
                Depth 24
                Modes "1600x1200" "1024x768" "800x600" "640x480"
        EndSubSection
EndSection

The challenge is, the X.org video device autodetection operates against devices attached to the PCI Bus, but this connects to the USB bus. So it's not as trivial as adding some pciids to the xserver.

$ lsusb
Bus 001 Device 005: ID 0711:0900 Magic Control Technology Corp. SVGA Adapter

[Bryce Harrington (bryce)]

Unfortunately, there seems to not be an active upstream for this driver. The driver was developed by Thomas Winischhofer, but it doesn't look like it's been touched since 2005.

There are no other bug reports at launchpad on the sisusb driver, and only one (from 2005) at bugs.freedesktop.org. This definitely feels like a really corner case hardware.

OTOH, this might be of interest in the context that now with DisplayLink we have other video devices which need detected on the USB bus, and if that is sorted out, this device could piggyback on that effort.

[Bryce Harrington (bryce)]

http://wiki.laptop.org/go/Adding_USB_SVGA

Looking through the sisusb source code, I see it has the voodoo in it to detect stuff on the USB bus, in sisusb_driver.c, function SiSUSBFindUSBDongle(). Something akin to this would need ported to xserver's driver selection logic.

[Mark Cariaga (mzc)]

I have the same issue on a Displaylink device. Diamond BVU195

[Timo Aaltonen (tjaalton)]

this driver has been removed from Ubuntu, closing it's bugs