/* Note: usb_control_msg returns negative value on error or length of the
* data that was written! */
result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300);
/* Note: usb_control_msg returns negative value on error or length of the
* data that was written! */
result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300);