| /* console.c: Routines that deal with sending and receiving IO | 
 |  *            to/from the current console device using the PROM. | 
 |  * | 
 |  * Copyright (C) 1995 David S. Miller (davem@davemloft.net) | 
 |  * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz) | 
 |  */ | 
 |  | 
 | #include <linux/types.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/sched.h> | 
 | #include <asm/openprom.h> | 
 | #include <asm/oplib.h> | 
 | #include <asm/system.h> | 
 | #include <linux/string.h> | 
 |  | 
 | extern int prom_stdin, prom_stdout; | 
 |  | 
 | /* Non blocking get character from console input device, returns -1 | 
 |  * if no input was taken.  This can be used for polling. | 
 |  */ | 
 | inline int | 
 | prom_nbgetchar(void) | 
 | { | 
 | 	char inc; | 
 |  | 
 | 	if (p1275_cmd("read", P1275_ARG(1,P1275_ARG_OUT_BUF)| | 
 | 			      P1275_INOUT(3,1), | 
 | 			      prom_stdin, &inc, P1275_SIZE(1)) == 1) | 
 | 		return inc; | 
 | 	else | 
 | 		return -1; | 
 | } | 
 |  | 
 | /* Non blocking put character to console device, returns -1 if | 
 |  * unsuccessful. | 
 |  */ | 
 | inline int | 
 | prom_nbputchar(char c) | 
 | { | 
 | 	char outc; | 
 | 	 | 
 | 	outc = c; | 
 | 	if (p1275_cmd("write", P1275_ARG(1,P1275_ARG_IN_BUF)| | 
 | 			       P1275_INOUT(3,1), | 
 | 			       prom_stdout, &outc, P1275_SIZE(1)) == 1) | 
 | 		return 0; | 
 | 	else | 
 | 		return -1; | 
 | } | 
 |  | 
 | /* Blocking version of get character routine above. */ | 
 | char | 
 | prom_getchar(void) | 
 | { | 
 | 	int character; | 
 | 	while((character = prom_nbgetchar()) == -1) ; | 
 | 	return (char) character; | 
 | } | 
 |  | 
 | /* Blocking version of put character routine above. */ | 
 | void | 
 | prom_putchar(char c) | 
 | { | 
 | 	prom_nbputchar(c); | 
 | 	return; | 
 | } | 
 |  | 
 | void | 
 | prom_puts(const char *s, int len) | 
 | { | 
 | 	p1275_cmd("write", P1275_ARG(1,P1275_ARG_IN_BUF)| | 
 | 			   P1275_INOUT(3,1), | 
 | 			   prom_stdout, s, P1275_SIZE(len)); | 
 | } |