/* function prototypes for a handspring visor */
static int visor_open (struct usb_serial_port *port, struct file *filp);
static void visor_close (struct usb_serial_port *port, struct file *filp);
/* function prototypes for a handspring visor */
static int visor_open (struct usb_serial_port *port, struct file *filp);
static void visor_close (struct usb_serial_port *port, struct file *filp);