Linux on a JVC MP-XP7250DE
I recently upgraded my laptop from a JVC MP-XP7210DE to its follow-up model, XP7250.
The new model has 10GB more disk space, 128MB more RAM, USB 2.0 and a
built-in wireless LAN adatopr. Those enhancements made the upgrade quite worthwhile
This time, I used a USB CD/DVD-ROM to boot off a Debian Woody CD.
Things worked out nicely, except that I had to explicitly disable the
use of framebuffer console again, since the display was kind of distorted
if framebuffer console was used.
It appears that current Linux kernels (v2.4 and v2.6) do not work
with the USB 1.1 subsystem of this laptop without a little bit of modification.
The standard ohci-hcd module of the Linux kernel performs a Host-Controller
Takeover, which fails on the XP7250. I suspect this is due to some
incompatibility in the BIOS. However, there are as of now
no updates for the BIOS available, so to get a working USB 1.1 and 2.0,
you need to patch your kernel. Here
is a patch for linux 2.6.4. Note however, that this "soltuion" is very
bad, and you should perhaps not use kernels patched in that
way for other machines than the xp7250.
Built-in Wireless LAN!
Oh yes, this so rocks! Did I already say that I like it? Hmm, probably.
The built-in wireless LAN card of the xp7250 is connected internally
via USB, and it is a Prism2.5 chipset based adaptor.
This card is currently only supported by the
, and not by the standard kernel yet.
You need to download one of the latest development snapshots (I use
0.2.1pre20), and build/install it. The latest version of linux-wlan-ng
in Debian does currently not yet support this USB card variant, so you will
need to compile from sources.
The xp7210 already survived 4 hours of continuus usage, if treated
with a bit of care (lowering processor speed via ACPI if appropriate).
My experience with the xp7250 is that it even survives a little longer.
I successfully used it for 4 hours and 30 minutes with one full charge
straight, which is really pretty neat.
Well, I should probably keep my mouth shut here, since I am really
not the person to ask about X Windows Specifics, but just to let you know,
the xp7250 uses a SiS630 graphics chipset, which does work with the
sis driver of XFree86 4.3. I have had problems with earlier versions
of XFree86, so make sure to use 4.3.