(self, bmRequestType, bRequest, wValue=0, wIndex=0,
            data_or_wLength = None, timeout = None)
r"""Do a control transfer on the endpoint 0.

        This method is used to issue a control transfer over the endpoint 0
        (endpoint 0 is required to always be a control endpoint).

        The parameters bmRequestType, bRequest, wValue and wIndex are the same
        of the USB Standard Control Request format.

        Control requests may or may not have a data payload to write/read.
        In cases which it has, the direction bit of the bmRequestType
        field is used to infer the desired request direction. For
        host to device requests (OUT), data_or_wLength parameter is
        the data payload to send, and it must be a sequence type convertible
        to an array object. In this case, the return value is the number
        of bytes written in the data payload. For device to host requests
        (IN), data_or_wLength is either the wLength parameter of the control
        request specifying the number of bytes to read in data payload, and
        the return value is an array object with data read, or an array
        object which the data will be read to, and the return value is the
        number of bytes read.
r"""Do a control transfer on the endpoint 0.
r Do a control transfer on the endpoint 0 .
def ctrl_transfer(self, bmRequestType, bRequest, wValue=0, wIndex=0,
            data_or_wLength = None, timeout = None):
        r"""Do a control transfer on the endpoint 0.

        This method is used to issue a control transfer over the endpoint 0
        (endpoint 0 is required to always be a control endpoint).

        The parameters bmRequestType, bRequest, wValue and wIndex are the same
        of the USB Standard Control Request format.

        Control requests may or may not have a data payload to write/read.
        In cases which it has, the direction bit of the bmRequestType
        field is used to infer the desired request direction. For
        host to device requests (OUT), data_or_wLength parameter is
        the data payload to send, and it must be a sequence type convertible
        to an array object. In this case, the return value is the number
        of bytes written in the data payload. For device to host requests
        (IN), data_or_wLength is either the wLength parameter of the control
        request specifying the number of bytes to read in data payload, and
        the return value is an array object with data read, or an array
        object which the data will be read to, and the return value is the
        number of bytes read.
        """
        try:
            buff = util.create_buffer(data_or_wLength)
        except TypeError:
            buff = _interop.as_array(data_or_wLength)

        self._ctx.managed_open()

        # Thanks to Johannes Stezenbach to point me out that we need to
        # claim the recipient interface
        recipient = bmRequestType & 3
        rqtype = bmRequestType & (3 << 5)
        if recipient == util.CTRL_RECIPIENT_INTERFACE \
                and rqtype != util.CTRL_TYPE_VENDOR:
            interface_number = wIndex & 0xff
            self._ctx.managed_claim_interface(self, interface_number)

        ret = self._ctx.backend.ctrl_transfer(
                                    self._ctx.handle,
                                    bmRequestType,
                                    bRequest,
                                    wValue,
                                    wIndex,
                                    buff,
                                    self.__get_timeout(timeout))

        if isinstance(data_or_wLength, array.array) \
                or util.ctrl_direction(bmRequestType) == util.CTRL_OUT:
            return ret
        elif ret != len(buff) * buff.itemsize:
            return buff[:ret]
        else:
            return buff
def ctrl_transfer ( self , bmRequestType , bRequest , wValue = 0 , wIndex = 0 , data_or_wLength = None , timeout = None ) : try : buff = util . create_buffer ( data_or_wLength ) except TypeError : buff = _interop . as_array ( data_or_wLength ) self . _ctx . managed_open ( ) # Thanks to Johannes Stezenbach to point me out that we need to # claim the recipient interface recipient = bmRequestType & 3 rqtype = bmRequestType & ( 3 << 5 ) if recipient == util . CTRL_RECIPIENT_INTERFACE and rqtype != util . CTRL_TYPE_VENDOR : interface_number = wIndex & 0xff self . _ctx . managed_claim_interface ( self , interface_number ) ret = self . _ctx . backend . ctrl_transfer ( self . _ctx . handle , bmRequestType , bRequest , wValue , wIndex , buff , self . __get_timeout ( timeout ) ) if isinstance ( data_or_wLength , array . array ) or util . ctrl_direction ( bmRequestType ) == util . CTRL_OUT : return ret elif ret != len ( buff ) * buff . itemsize : return buff [ : ret ] else : return buff