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/*
* 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@caip.rutgers.edu)
* Copyright (C) 1998 Pete Zaitcev <zaitcev@yahoo.com>
*/
#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 void restore_current(void);
/* Non blocking get character from console input device, returns -1
* if no input was taken. This can be used for polling.
*/
static int prom_nbgetchar(char *buf)
{
unsigned long flags;
int i = -1;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
i = (*(romvec->pv_nbgetchar))();
if (i != -1) {
*buf = i;
i = 0;
}
break;
case PROM_V2:
case PROM_V3:
if ((*(romvec->pv_v2devops).v2_dev_read)(*romvec->pv_v2bootargs.fd_stdin,
buf, 0x1) == 1)
i = 0;
break;
default:
break;
};
restore_current();
spin_unlock_irqrestore(&prom_lock, flags);
return i; /* Ugh, we could spin forever on unsupported proms ;( */
}
/* Non blocking put character to console device, returns -1 if
* unsuccessful.
*/
static int prom_nbputchar(const char *buf)
{
unsigned long flags;
int i = -1;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
i = (*(romvec->pv_nbputchar))(*buf);
break;
case PROM_V2:
case PROM_V3:
if ((*(romvec->pv_v2devops).v2_dev_write)(*romvec->pv_v2bootargs.fd_stdout,
buf, 0x1) == 1)
i = 0;
break;
default:
break;
};
restore_current();
spin_unlock_irqrestore(&prom_lock, flags);
return i; /* Ugh, we could spin forever on unsupported proms ;( */
}
/* Blocking version of get character routine above. */
void prom_getchar(char *buf)
{
while (1) {
int err = prom_nbgetchar(buf);
if (!err)
break;
}
}
/* Blocking version of put character routine above. */
void prom_putchar(const char *buf)
{
while (1) {
int err = prom_nbputchar(buf);
if (!err)
break;
}
}
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