1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/*
* 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(void)
{
static char inc;
int i = -1;
unsigned long flags;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
i = (*(romvec->pv_nbgetchar))();
break;
case PROM_V2:
case PROM_V3:
if( (*(romvec->pv_v2devops).v2_dev_read)(*romvec->pv_v2bootargs.fd_stdin , &inc, 0x1) == 1) {
i = inc;
} else {
i = -1;
}
break;
default:
i = -1;
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(char c)
{
static char outc;
unsigned long flags;
int i = -1;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
i = (*(romvec->pv_nbputchar))(c);
break;
case PROM_V2:
case PROM_V3:
outc = c;
if( (*(romvec->pv_v2devops).v2_dev_write)(*romvec->pv_v2bootargs.fd_stdout, &outc, 0x1) == 1)
i = 0;
else
i = -1;
break;
default:
i = -1;
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. */
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)
{
while(prom_nbputchar(c) == -1) ;
}
|
