arch/sparc/prom/console.c

   1 /* $Id: console.c,v 1.25 2001/10/30 04:54:22 davem Exp $
   2  * console.c: Routines that deal with sending and receiving IO
   3  *            to/from the current console device using the PROM.
   4  *
   5  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  * Copyright (C) 1998 Pete Zaitcev <zaitcev@yahoo.com>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/kernel.h>
  11 #include <linux/sched.h>
  12 #include <asm/openprom.h>
  13 #include <asm/sun4prom.h>
  14 #include <asm/oplib.h>
  15 #include <asm/system.h>
  16 #include <linux/string.h>
  17
  18 extern void restore_current(void);
  19
  20 /* Non blocking get character from console input device, returns -1
  21  * if no input was taken.  This can be used for polling.
  22  */
  23 int
  24 prom_nbgetchar(void)
  25 {
  26         static char inc;
  27         int i = -1;
  28         unsigned long flags;
  29
  30         spin_lock_irqsave(&prom_lock, flags);
  31         switch(prom_vers) {
  32         case PROM_V0:
  33         case PROM_SUN4:
  34                 i = (*(romvec->pv_nbgetchar))();
  35                 break;
  36         case PROM_V2:
  37         case PROM_V3:
  38                 if( (*(romvec->pv_v2devops).v2_dev_read)(*romvec->pv_v2bootargs.fd_stdin , &inc, 0x1) == 1) {
  39                         i = inc;
  40                 } else {
  41                         i = -1;
  42                 }
  43                 break;
  44         default:
  45                 i = -1;
  46                 break;
  47         };
  48         restore_current();
  49         spin_unlock_irqrestore(&prom_lock, flags);
  50         return i; /* Ugh, we could spin forever on unsupported proms ;( */
  51 }
  52
  53 /* Non blocking put character to console device, returns -1 if
  54  * unsuccessful.
  55  */
  56 int
  57 prom_nbputchar(char c)
  58 {
  59         static char outc;
  60         unsigned long flags;
  61         int i = -1;
  62
  63         spin_lock_irqsave(&prom_lock, flags);
  64         switch(prom_vers) {
  65         case PROM_V0:
  66         case PROM_SUN4:
  67                 i = (*(romvec->pv_nbputchar))(c);
  68                 break;
  69         case PROM_V2:
  70         case PROM_V3:
  71                 outc = c;
  72                 if( (*(romvec->pv_v2devops).v2_dev_write)(*romvec->pv_v2bootargs.fd_stdout, &outc, 0x1) == 1)
  73                         i = 0;
  74                 else
  75                         i = -1;
  76                 break;
  77         default:
  78                 i = -1;
  79                 break;
  80         };
  81         restore_current();
  82         spin_unlock_irqrestore(&prom_lock, flags);
  83         return i; /* Ugh, we could spin forever on unsupported proms ;( */
  84 }
  85
  86 /* Blocking version of get character routine above. */
  87 char
  88 prom_getchar(void)
  89 {
  90         int character;
  91         while((character = prom_nbgetchar()) == -1) ;
  92         return (char) character;
  93 }
  94
  95 /* Blocking version of put character routine above. */
  96 void
  97 prom_putchar(char c)
  98 {
  99         while(prom_nbputchar(c) == -1) ;
 100         return;
 101 }