On Fri, Sep 11, 2020 at 04:54:08AM +0900, Hector Martin wrote: > On 11/09/2020 03.51, James Hilliard wrote: > > I haven't tested this yet but my assumption was that either a kernel driver > > or libusb can issue usb control messages, but both can not be bound to > > a device at the same time. I figured this wouldn't have come up when you > > tested your python script since the script likely predated adding the brick > > PID > > to the ftdi_sio Linux kernel driver. > > Binding to interfaces is exclusive, but global device control messages are > not issued to an interface. I think it should work even if the kernel driver > is bound (this is how lsusb works too, since it issues control requests even > to devices bound to drivers). Even if it is necessary to unbind it, though, > libusb already provides a single function to do that > (libusb_detach_kernel_driver).
You really should unbind the device from the driver when doing stuff like this, so the kernel doesn't get confused. thanks, greg k-h
