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Device remains in use after manager is stopped
I get usb.core.USBError: [Errno 16] Resource busy
when creating another ant.fs.manager.Application
instance using the same device:
With this test script I get the following traceback. https://gist.github.com/jonnylamb/a794c732bff1e1883d1a
Traceback (most recent call last):
File "/tmp/garmin.py", line 34, in <module>
b = GarminTest()
File "/home/jonny/src/openant/ant/fs/manager.py", line 104, in __init__
self._node = Node()
File "/home/jonny/src/openant/ant/easy/node.py", line 56, in __init__
self.ant = Ant()
File "/home/jonny/src/openant/ant/base/ant.py", line 68, in __init__
self._driver.open()
File "/home/jonny/src/openant/ant/base/driver.py", line 185, in open
dev.set_configuration()
File "/home/jonny/src/pyusb/usb/core.py", line 559, in set_configuration
self._ctx.managed_set_configuration(self, configuration)
File "/home/jonny/src/pyusb/usb/core.py", line 92, in managed_set_configuration
self.backend.set_configuration(self.handle, cfg.bConfigurationValue)
File "/home/jonny/src/pyusb/usb/backend/libusb1.py", line 724, in set_configuration
_check(self.lib.libusb_set_configuration(dev_handle.handle, config_value))
File "/home/jonny/src/pyusb/usb/backend/libusb1.py", line 554, in _check
raise USBError(_str_error[ret], ret, _libusb_errno[ret])
usb.core.USBError: [Errno 16] Resource busy
Yes, this is intended. The Application class takes hold of this in the init function. Might be able to work around this by using del
on the first object before creating a new one. But only one Application object is intended to be used during the liftetime of the program. That doesn't stop one from using multiple channels and similar of course.
del a
before creating b
does not work.
How do you suggest I create another connection in the same process after the first one has disconnected then?
Yeah, that is a good question - and something I haven't tried yet. I'll experiment a bit with this and see if I can find a good solution for this.
Thanks, would be incredible to get a good solution to this.
Relatedly, after swapping the dev.set_configuration()
and dev.reset()
calls in ant/base/driver.py
I found I could make multiple Application
instances (to the same device) but only after receiving a Resource busy
exception first, as quoted above.
I expect the main solution here will be gracely close the channel.
Will be possible with Pull #54.
Also see examples for this.