How can you use X on a Notebook and its Docking Station?

Jim sends in this intriguing question: "I have a Dell notebook with a docking station. Does Linux need to know that I use a docking station? If not, do I configure Xwindows for my LCD screen or for the monitor on the docking station? Or does Xwindows support multiple hardware configurations?"

My experience

[dattaway]

I have a Gateway Solo 2200 that has a CT65554 video chip that works well, except it only has 2MB of memory and a max dot rate of 100MHz. So, I played around with various cards in the docking station. The only disadvantage is that X for me seems to only recognize the video card that was used when booted up.

If the laptop was plugged into the docking station at bootup, it would get the card on that pci bridge. I did not read much into complex setups like this, but I'm sure X could be made to switch between the two cards.

Otherwise, the docking station acts like a real handy hot swapable pci and isa bus. The only problems is initializing scsi and video cards anytime after bootup when the docking station is turned back on. The video and scsi cards when powered back up seem to be uninitialized. Scsi drivers seem to be very unforgiving when the card does not want to talk. I have tried the AHA2940 and initio 9100uw, both with the same results.

Oh, and another problem I have with the docking station is that playing sounds through the laptop's sound card can crash Linux while it is hot docking. As long as I stop the mp3 player while I dock and undock, it will not crash.

Linux likes my docking station. It sees it as more pci bridges that are welcome on the system at anytime. This station was very unusable with Windows95 and NT. I am no fan of rebooting.

I may have to make an ugly and clumsy patch to the kernel to allow cards like the video and scsi to get restarted. The APM seems to do this automagicaly with PCMCIA cards. Has anyone tried this with a docking station?

My solution

[Lightborn]

Since I could only run 1024x768 while undocked but 1280x1024 when docked, I made two different XF86Config files and then had scripts dock and undock that would just symlink the appropriate file. Also had the scripts kill and restart gpm since the mouse went weird otherwise.

Work with _both_ screens?

[g.a.g]

Does anyone know whether it is possible to have both screens working? X should support this, as (they say) does Windows98 - but I would guess this can only work in the configuration with the extra video card in the docking station; or is there a workaround for digitally signalled laptop displays?

Work with _both_ screens?

[Lally Singh]

that requires that the video cards themselves
support that feature. afaik, only a few cards
support multihead. i think matrox & ibm & another
i don't remember are the only ones who have
models that support it.

so.. it can be done with a soldering iron & alot
of spare time :-)