def __init__(self, device, setting, name=None, default_timeout_ms=None):
"""Initialize a local libusb-based USB Handle.
Arguments:
device: libusb device to connect to.
setting: libusb setting with the endpoints to use for data reads/writes.
name: Name for the device, used for log messages only.
default_timeout_ms: Default timeout, in milliseconds, for reads/writes.
Raises:
InvalidEndpointsError: If the setting provided does not have exactly one
in endpoint and one out endpoint. Currently, this is the only type of
interface supported.
IOError: If the device has been disconnected.
"""
super(LibUsbHandle,
self).__init__(device.getSerialNumber(),
name=name,
default_timeout_ms=default_timeout_ms)
self._setting = setting
self._device = device
self._read_endpoint = None
self._write_endpoint = None
self._handle = None
for endpoint in self._setting.iterEndpoints():
address = endpoint.getAddress()
if address & libusb1.USB_ENDPOINT_DIR_MASK == libusb1.LIBUSB_ENDPOINT_IN:
if self._read_endpoint is not None:
raise usb_exceptions.InvalidEndpointsError(
'Multiple in endpoints found')
self._read_endpoint = address
else:
if self._write_endpoint is not None:
raise usb_exceptions.InvalidEndpointsError(
'Multiple out endpoints found')
self._write_endpoint = address
if self._read_endpoint is None:
raise usb_exceptions.InvalidEndpointsError('Missing in endpoint')
if self._write_endpoint is None:
raise usb_exceptions.InvalidEndpointsError('Missing out endpoint')
handle = self._device.open()
iface_number = self._setting.getNumber()
try:
if handle.kernelDriverActive(iface_number):
handle.detachKernelDriver(iface_number)
except libusb1.USBError as exception:
if exception.value == libusb1.LIBUSB_ERROR_NOT_FOUND:
_LOG.warning('Kernel driver not found for interface: %s.',
iface_number)
else:
raise usb_exceptions.LibusbWrappingError(
exception, '%s failed to detach kernel driver', self)
# Try to claim the interface, if the device is gone, raise an IOError
try:
handle.claimInterface(iface_number)
except libusb1.USBError as exception:
raise usb_exceptions.LibusbWrappingError(
exception, '%s failed to claim interface: %d', self,
iface_number)
self._handle = handle
self._interface_number = iface_number
def iter_open(cls,
name=None,
interface_class=None,
interface_subclass=None,
interface_protocol=None,
serial_number=None,
port_path=None,
default_timeout_ms=None):
"""Find and yield locally connected devices that match.
Note that devices are opened (and interfaces claimd) as they are yielded.
Any devices yielded must be Close()'d.
Args:
name: Name to give *all* returned handles, used for logging only.
interface_class: USB interface_class to match.
interface_subclass: USB interface_subclass to match.
interface_protocol: USB interface_protocol to match.
serial_number: USB serial_number to match.
port_path: USB Port path to match, like X-X.X.X
default_timeout_ms: Default timeout in milliseconds of reads/writes on
the handles yielded.
Yields:
UsbHandle instances that match any non-None args given.
Raises:
LibusbWrappingError: When a libusb call errors during open.
"""
ctx = usb1.USBContext()
try:
devices = ctx.getDeviceList(skip_on_error=True)
except libusb1.USBError as exception:
raise usb_exceptions.LibusbWrappingError(
exception, 'Open(name=%s, class=%s, subclass=%s, protocol=%s, '
'serial=%s, port=%s) failed', name, interface_class,
interface_subclass, interface_protocol, serial_number,
port_path)
for device in devices:
try:
if (serial_number is not None
and device.getSerialNumber() != serial_number):
continue
if (port_path is not None
and cls._device_to_sysfs_path(device) != port_path):
continue
for setting in device.iterSettings():
if (interface_class is not None
and setting.getClass() != interface_class):
continue
if (interface_subclass is not None
and setting.getSubClass() != interface_subclass):
continue
if (interface_protocol is not None
and setting.getProtocol() != interface_protocol):
continue
yield cls(device,
setting,
name=name,
default_timeout_ms=default_timeout_ms)
except libusb1.USBError as exception:
if (exception.value != libusb1.libusb_error.
forward_dict['LIBUSB_ERROR_ACCESS']):
raise