arch/sparc/prom/console_32.c

   1 /*
   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/oplib.h>
  14 #include <asm/system.h>
  15 #include <linux/string.h>
  16
  17 extern void restore_current(void);
  18
  19 /* Non blocking get character from console input device, returns -1
  20  * if no input was taken.  This can be used for polling.
  21  */
  22 static int prom_nbgetchar(void)
  23 {
  24         static char inc;
  25         int i = -1;
  26         unsigned long flags;
  27
  28         spin_lock_irqsave(&prom_lock, flags);
  29         switch(prom_vers) {
  30         case PROM_V0:
  31                 i = (*(romvec->pv_nbgetchar))();
  32                 break;
  33         case PROM_V2:
  34         case PROM_V3:
  35                 if( (*(romvec->pv_v2devops).v2_dev_read)(*romvec->pv_v2bootargs.fd_stdin , &inc, 0x1) == 1) {
  36                         i = inc;
  37                 } else {
  38                         i = -1;
  39                 }
  40                 break;
  41         default:
  42                 i = -1;
  43                 break;
  44         };
  45         restore_current();
  46         spin_unlock_irqrestore(&prom_lock, flags);
  47         return i; /* Ugh, we could spin forever on unsupported proms ;( */
  48 }
  49
  50 /* Non blocking put character to console device, returns -1 if
  51  * unsuccessful.
  52  */
  53 static int prom_nbputchar(char c)
  54 {
  55         static char outc;
  56         unsigned long flags;
  57         int i = -1;
  58
  59         spin_lock_irqsave(&prom_lock, flags);
  60         switch(prom_vers) {
  61         case PROM_V0:
  62                 i = (*(romvec->pv_nbputchar))(c);
  63                 break;
  64         case PROM_V2:
  65         case PROM_V3:
  66                 outc = c;
  67                 if( (*(romvec->pv_v2devops).v2_dev_write)(*romvec->pv_v2bootargs.fd_stdout, &outc, 0x1) == 1)
  68                         i = 0;
  69                 else
  70                         i = -1;
  71                 break;
  72         default:
  73                 i = -1;
  74                 break;
  75         };
  76         restore_current();
  77         spin_unlock_irqrestore(&prom_lock, flags);
  78         return i; /* Ugh, we could spin forever on unsupported proms ;( */
  79 }
  80
  81 /* Blocking version of get character routine above. */
  82 char
  83 prom_getchar(void)
  84 {
  85         int character;
  86         while((character = prom_nbgetchar()) == -1) ;
  87         return (char) character;
  88 }
  89
  90 /* Blocking version of put character routine above. */
  91 void
  92 prom_putchar(char c)
  93 {
  94         while(prom_nbputchar(c) == -1) ;
  95 }