arch/sparc/prom/devops_64.c

   1 /*
   2  * devops.c:  Device operations using the PROM.
   3  *
   4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   6  */
   7 #include <linux/types.h>
   8 #include <linux/kernel.h>
   9 #include <linux/sched.h>
  10
  11 #include <asm/openprom.h>
  12 #include <asm/oplib.h>
  13
  14 /* Open the device described by the string 'dstr'.  Returns the handle
  15  * to that device used for subsequent operations on that device.
  16  * Returns 0 on failure.
  17  */
  18 int
  19 prom_devopen(const char *dstr)
  20 {
  21         unsigned long args[5];
  22
  23         args[0] = (unsigned long) "open";
  24         args[1] = 1;
  25         args[2] = 1;
  26         args[3] = (unsigned long) dstr;
  27         args[4] = (unsigned long) -1;
  28
  29         p1275_cmd_direct(args);
  30
  31         return (int) args[4];
  32 }
  33
  34 /* Close the device described by device handle 'dhandle'. */
  35 int
  36 prom_devclose(int dhandle)
  37 {
  38         unsigned long args[4];
  39
  40         args[0] = (unsigned long) "close";
  41         args[1] = 1;
  42         args[2] = 0;
  43         args[3] = (unsigned int) dhandle;
  44
  45         p1275_cmd_direct(args);
  46
  47         return 0;
  48 }
  49
  50 /* Seek to specified location described by 'seekhi' and 'seeklo'
  51  * for device 'dhandle'.
  52  */
  53 void
  54 prom_seek(int dhandle, unsigned int seekhi, unsigned int seeklo)
  55 {
  56         unsigned long args[7];
  57
  58         args[0] = (unsigned long) "seek";
  59         args[1] = 3;
  60         args[2] = 1;
  61         args[3] = (unsigned int) dhandle;
  62         args[4] = seekhi;
  63         args[5] = seeklo;
  64         args[6] = (unsigned long) -1;
  65
  66         p1275_cmd_direct(args);
  67 }