MAX_IN_PACKET
ir->buf_in = usb_alloc_coherent(udev, MAX_IN_PACKET, GFP_KERNEL,
usb_fill_int_urb(ir->urb_in, udev, pipein, ir->buf_in, MAX_IN_PACKET,
usb_free_coherent(udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
usb_free_coherent(ir->udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);