Device is unresponsive after first comand

[flyingclimber]

#1 Send any valid command
#2 Try to send another

The second command will fail and/or timeout even though it is valid. Looking through the raw USB logs (/sys/kernel/debug/usb/usbmon/2u) I can see two unnecessary control transfers at the very beginning.

ffff88001bf93140 3167498047 S Co:2:008:0 s 00 09 0001 0000 0000 0
ffff88001bf93140 3169425832 C Co:2:008:0 0 0
ffff88001bf93680 3169427321 S Bo:2:008:2 -115 9 = ff000000 00000002 00
ffff88001bf93680 3169428141 C Bo:2:008:2 0 9 >
ffff88001bf93680 3169428531 S Bi:2:008:1 -115 512 <
ffff88001bf93680 3169439981 C Bi:2:008:1 0 512 = ff000000 00000000 ff000000 00000000 ff000000 00000000 ff000000 00000000

[flyingclimber]

Traced this down to

DEV.set_configuration()
...

/usr/local/lib/python2.7/dist-packages/usb/core.py(128)managed_set_configuration()
-> self.backend.set_configuration(self.handle, cfg.bConfigurationValue)
(Pdb)
--Call--
/usr/local/lib/python2.7/dist-packages/usb/backend/libusb1.py(728)set_configuration()
-> @methodtrace(_logger)
(Pdb)
/usr/local/lib/python2.7/dist-packages/usb/backend/libusb1.py(730)set_configuration()
-> _check(self.lib.libusb_set_configuration(dev_handle.handle, config_value))
(Pdb)
--Call--

[flyingclimber]

Commenting out /usr/local/lib/python2.7/dist-packages/usb/backend/libusb1.py(730) causes the first lookup to fail but all subsequent ones work just fine.

That'll let me continue working but doesn't fix the underlying issue