[Mac OS X] Working dfu-util
Dr. H. Nikolaus Schaller
hns at computer.org
Tue Aug 7 20:09:37 CEST 2007
Am 07.08.2007 um 13:50 schrieb Simon Moore:
> Dr. H. Nikolaus Schaller wrote:
>> One more question - how did you manage that dfu-util is not
>> blocked by the AppleUSBCDC driver which also tries to bind to the
>> same USB interface?
>> OpenMoko community mailing list
>> community at lists.openmoko.org
> It could be a cause of why I have to disconnect & reconnect the USB
> cable for each invocation of dfu-util. I have seen this in the
> output at times:
> Cannot claim interface: usb_claim_interface: couldn't claim interface
Yes, this is the same symptom as I have.
> I just checked with kextstat (kextstat | grep CDC), and it does
> show the many CDC drivers being loaded when the Neo is connected.
> They are not present when the Neo is not connected.
> A quick google shows you can manually unload the drivers (not sure
> the -b is correct):
> sudo kextunload -b com.apple.driver.AppleUSBCDC
> sudo kextunload -b com.apple.driver.AppleUSBCDCACMControl
> sudo kextunload -b com.apple.driver.AppleUSBCDCECMData
> sudo kextunload -b com.apple.driver.AppleUSBCDCACMData
> Then the next time the Neo is connected the CDC driver is not loaded.
Not necessarily - there will be a race condition between dfu-util and
the kextloader (trying to reload it).
> I just tried this, but it's strange. Unloading AppleUSBCDC worked
> ok. Unloading AppleUSBCDCACMControl threw an error that it could
> not unload, but thereafter all the CDC drivers were no longer being
> loaded. But I still had another 'couldn't claim interface' error.
> Maybe the 'couldn't claim interface' error is not resulting from
> the Apple drivers? I don't really know enough about USB or libusb,
> but the NULL pointer problems (e.g bug #672) make me suspicious.
Yes, there might be other bugs - but I think it is the AppleUSBCDC
which already owns the interface (exclusively). Harald Welte
mentioned that on the owner's and u-boot list.
> So far my most successful approach is the disconnect & reconnect of
> the USB cable...
I have the additional approach by installing AJZaurusUSB 0.5.2 which
is given a higher driver probe priority to match the device than
AppleUSBCDC. For me it worked, but I have no positive feedback from
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