spin_unlock_irqrestore(&port->ip_port->lock, pflags); 
static void ioc4_cb_output_lowat(struct ioc4_port *port){	/* ip_lock is set on the call here */	if (port->ip_port) {		transmit_chars(port->ip_port);	}}
10457	/local/tlutelli/issta_data/temp/c/2005_temp/2005/10457/396dc44bcac58f464b7b23c345052e37881cccea/ioc4_serial.c/buggy/drivers/serial/ioc4_serial.c