> Eric House wrote: > > I have a Dell laptop running Ubuntu and a Virgin Mobile "MiFi" > > cellular wifi hotspot. The MiFi is great but for one bug: when you > > plug its USB cable into the laptop to charge it stops being a hotspot, > > so you have to carry a separate USB wallwart to charge it. > > > > I'm pretty sure this is unnecessary -- that if I could get my laptop > > to pretend to be a mere USB wallwart I could prevent the loss of wifi. > > Googling on the subject turns up instructions for fixing this by > > disabling USB Mass Storage mode on windows thus: > > > > # KB823732 explains how you can disable USB device support by changing > > # the Start value of > > # HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor to 4 > > > > The closest I could think to try on GNU/Linux was to prevent the > > usb_storage module from loading, but this didn't work. The MiFi still > > shuts down, meaning it's been signalled in some way by the laptop. > > > > Can anybody suggest how to do this, or where to read or ask for > > further information? I'm happy to hack the drivers if that's what > > it's going to take. It's apparently possible to fix this by removing > > the two inner contacts from a USB cable end, but I don't want to carry > > a second cable either -- if I can avoid it.
> Eric House > Googling on > linux disable mass storage > At > <http://www.linuxquestions.org/questions/linux-newbie-8/how-to-disable-usb-mass-storage-device-usb-drive-in-linux-651262/> > > it says ... > "In linux it's even more easily done, by unloading the usb_storage module: > > modprobe -r usb_storage > > from the command line" > ... then it goes on about how to do that permanently, if that is of any > interest. > Does that help? No. That's the first thing I tried. Another reply suggested disabling the core USB module, which I *can* do on my laptop, but that doesn't help either. BTW, the MiFi presents itself as an ISO 9600 FS -- i.e. it looks like a CD-ROM to Ubuntu. I'm not even sure what the point of that is, but then I haven't looked at what files are there -- and can't or I'll lose the connection over which I'm writing this. :-) > The inner contacts are the data lines, and the outer contacts are > power. I'm not sure of the data lines even exist on a wall wart. The > USB standard requires that initialization happens within milliseconds > of connecting the cable, and some of that has to happen before the > computer even knows that it's a USB Mass storage device. Depending on > how the MiFi device responds to this disabling USB Mass Storage might > be too late. Have you confirmed that it actually works in Windows? No. That's an excellent question/idea. Before I chase this much further I'll find myself a windows box. > Modern Linux will typically load this driver automatically as soon as > it's detected, and in some cases may be built into the kernel rather > than loaded on use. > > On my ubuntu system the place to prevent loading the driver would be. > /etc/modprobe.d/blacklist.conf I did that, and confirmed with lsusb that it was not being loaded. If I rmmod'd it and did not add it to the blacklist it would get reloaded when I connected the USB cable, but with the blacklist mod that was prevented. Wifi still shuts down, though. Thanks! --Eric -- ****************************************************************************** * From the desktop of: Eric House, [email protected] * * Crosswords for Android now in beta: via the Market or xwords.sf.net * ****************************************************************************** _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
