extern int console_open_chan(struct line *line, struct console *co);
extern void deactivate_chan(struct chan *chan, int irq);
extern void reactivate_chan(struct chan *chan, int irq);
extern int console_open_chan(struct line *line, struct console *co);
extern void deactivate_chan(struct chan *chan, int irq);
extern void reactivate_chan(struct chan *chan, int irq);