LIBUSB_ERROR_ACCESS from usb1 on Windows under unknown circumstances with CW Connect

[colinoflynn]

Have seen an issue on a specific Python install on Windows 11, with:

• Python = Python 3.7.12
• libusb1 = 2.0.1 (seems to happen with older versions as well)

Note on the exact same computer a different Python3 install (3.7.7) works perfectly. Unclear if this is install-specific or version-specific bug. Trying to connect causes a LIBUSB_ERROR_ACCESS exception. Running this as Administrator in Windows still has same result (and these errors are normally Unix permission issue, not Windows):

C:\Python\WPy64-37120\scripts>python
Python 3.7.12 (44db26267d0a, Oct 24 2021, 14:22:11)
[PyPy 7.3.7 with MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>> import chipwhisperer as cw
>>>> scope = cw.scope()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "c:\dev\chipwhisperer\software\chipwhisperer\__init__.py", line 327, in scope
    scope_type = get_cw_type(**kwargs)
  File "c:\dev\chipwhisperer\software\chipwhisperer\common\utils\util.py", line 520, in get_cw_type
    device = cwusb.find(serial_number=sn, idProduct=possible_ids, hw_location=hw_location)
  File "c:\dev\chipwhisperer\software\chipwhisperer\hardware\naeusb\naeusb.py", line 325, in find
    sns = ["{}:{}".format(dev.getProduct(), dev.getSerialNumber()) for dev in dev_list]
  File "c:\dev\chipwhisperer\software\chipwhisperer\hardware\naeusb\naeusb.py", line 325, in <listcomp>
    sns = ["{}:{}".format(dev.getProduct(), dev.getSerialNumber()) for dev in dev_list]
  File "C:\Python\WPy64-37120\pypy3.7-v7.3.7-win64\site-packages\usb1\__init__.py", line 2004, in getProduct
    return self.open().getProduct()
  File "C:\Python\WPy64-37120\pypy3.7-v7.3.7-win64\site-packages\usb1\__init__.py", line 2056, in open
    mayRaiseUSBError(libusb1.libusb_open(self.device_p, byref(handle)))
  File "C:\Python\WPy64-37120\pypy3.7-v7.3.7-win64\site-packages\usb1\__init__.py", line 128, in mayRaiseUSBError
    __raiseUSBError(value)
  File "C:\Python\WPy64-37120\pypy3.7-v7.3.7-win64\site-packages\usb1\__init__.py", line 120, in raiseUSBError
    raise __STATUS_TO_EXCEPTION_DICT.get(value, __USBError)(value)
usb1.USBErrorAccess: LIBUSB_ERROR_ACCESS [-3]

It seems to be triggered after so many calls to the USB device. Calling for example:

dev.getProduct()
dev.getProduct()

Will result in the first one working but second one failing. This can be seen by modifying the code in the get_possible_devices(). It doesn't seem to matter what the call is - for example calling dev.getSerialNumber() has same effect, first one works but second one fails.

Unclear if there is a fix - leaving issue open [for now - will close] in case anyone else runs into this so there is some hit for the search term!