If the modem doesn't have any other power sources than USB, just

removing the modem's and USB modules, and the modprobing them again

should help.
Just take care if you have it connected to the PC with a USB keyboard ;)
--

Tomasz Chmielewski

http://blog.wpkg.org
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actually, I have a USB keyboard, could that be the problem? why?
removing and adding modules doesn't solve my problem... The USB has

several functions: modem and usb mass storage and only the storage one
any thoughts?
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Because when you remove USB modules, USB devices, including USB 
What modules exactly do you unload/load again, in what order, using

which commands?
--

Tomasz Chmielewski

http://blog.wpkg.org

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I also have a mobile phone connected, a gps and a keyboard, i do the

following:
ecar@ecar:~$ lsmod | grep usb

usbserial              29928  1 pl2303

usbtouchscreen          8708  0

usbcore               130304  7

libusual,pl2303,usbserial,usbtouchscreen,ehci_hcd,uhci_hcd

ecar@ecar:~$ rmmod pl2303

ERROR: Removing 'pl2303': Operation not permitted

ecar@ecar:~$ sudo rmmod pl2303

ecar@ecar:~$ sudo rmmod usbserial

ecar@ecar:~$ modprobe usbserial

FATAL: Error inserting usbserial

(/lib/modules/2.6.17-11-386/kernel/drivers/usb/serial/usbserial.ko):

Operation not permitted

(reverse-i-search)`mod': cd backup_modules/

(reverse-i-search)`modpro': sudo modprobe  ehci_hcd

ecar@ecar:~$ sudo modprobe usbserial vendor=0x12d1 product=0x1003

ecar@ecar:~$ lsmod | grep usb

usbserial              29928  0

usbtouchscreen          8708  0

usbcore               130304  6

usbserial,libusual,usbtouchscreen,ehci_hcd,uhci_hcd
but only when I unplug and plug manually, the modem starts up ...

Because of that i wanted to unplug/plug via scripting (software way)
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Only then It's not enough. You also have to remove ehci_hcd / uhci_hcd

/ ohci_hcd.the device will be powered off (unless the method described 
cd backup_modules/? Where do you keep your modules?
--

Tomasz Chmielewski

http://blog.wpkg.org

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if I remove ehci_hcd / uhci_hcd / ohci_hcd , some other devices like

touchscreen, GPS and keyboard could stop working.
backup_modules doesn't matter here, is my personal backup. I have tried

also to recompile some modules because some times my modem huaweis is

recognized like usb mass storage.
I will try a how to guide to do what oliver commented
"You can use the bind & unbind attributes in sysfs"
where can i find information about that?
kindest regards
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gee, here:

http://lkml.org/lkml/2007/5/28/193

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You can use the bind & unbind attributes in sysfs.
	Regards

		Oliver
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You might try this (bottom of the page):

http://lkml.org/lkml/2007/5/28/193
regards,

--

Jiri Slaby (jirislaby@gmail.com)

Faculty of Informatics, Masaryk University

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