HelenOS sources

ns8250_unregister_interrupt_handler  937 uspace/drv/char/ns8250/ns8250.c 		ns8250_unregister_interrupt_handler(ns);
ns8250_unregister_interrupt_handler  965 uspace/drv/char/ns8250/ns8250.c 	ns8250_unregister_interrupt_handler(ns);
HelenOS homepage, sources at GitHub