LIBUSB_DEBUG_FUNCTION
DPRINTF(dev->ctx, LIBUSB_DEBUG_FUNCTION, "libusb_submit_transfer enter");
DPRINTF(dev->ctx, LIBUSB_DEBUG_FUNCTION, "libusb_submit_transfer leave %d", err);
DPRINTF(dev->ctx, LIBUSB_DEBUG_FUNCTION, "libusb_cancel_transfer enter");
DPRINTF(dev->ctx, LIBUSB_DEBUG_FUNCTION, "libusb_cancel_transfer leave");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_init complete");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_open write failed!");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_open_device_width_vid_pid enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_open_device_width_vid_pid leave");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_close write failed!");
case LIBUSB_DEBUG_FUNCTION: \
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb10_handle_events_sub enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_wait_for_event enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_handle_events_timeout_completed enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_handle_events_timeout_completed exit");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_bulk_transfer enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_bulk_transfer leave");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_interrupt_transfer enter");
DPRINTF(ctx, LIBUSB_DEBUG_FUNCTION, "libusb_interrupt_transfer leave");