dave, Thanks alot for useful information. Is there any way in which i can verify that is it the fault of device (i.e device is trying to draw more current) or my host controller is faulty (as you mentioned that some Host controllers behave in such way)? Thanks PC --- David Brownell <david-b@xxxxxxxxxxx> wrote: > > > i am using 2.6.11, > > Try to use a more current kernel. Likely it won't > matter > here, but 2.6.11 is over 18 months old by now ... :) > > > > and EHCI HCD. during boot up i get > > following message: > > > > "usb 1-0:1.0: over-current change on port 1" > > > > and after the system is up none of the USB device > > connected to USB port are detected. > > > > can you please tell me what over-current change > mean. > > USB devices can draw a certain amount of current, > with > a maximum of 500 mA in high power configurations. > > USB hubs, like root hubs, may be able to detect when > that current limit is exceeded; if so, it's reported > as an "over current" error. > > > > and Is this error responsible for my device not > > getting detected. > > Likely. When a port issues an overcurrent fault, > the device connected to it is disconnected. > > > We have seen cases where some USB controllers (EHCI > and > UHCI, I don't recall it with OHCI) *wrongly* report > such > over-current errors ... at least, "wrongly" in the > sense > that no device is connected, so we think the > motherboard > must be at fault, badly wired or whatever. > > - Dave > > > -- > Kernelnewbies: Help each other learn about the Linux > kernel. > Archive: > http://mail.nl.linux.org/kernelnewbies/ > FAQ: http://kernelnewbies.org/faq/ > > Vision without action is merely a dream, action without vision is wastage of time, vision and action together can change the world .... __________________________________________________________ Yahoo! India Answers: Share what you know. Learn something new http://in.answers.yahoo.com/ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
