blob: 9f1a95c91ad12f3b7742c381d9a0b864f79e97bb [file] [log] [blame]
Adrian Bunk88278ca2008-05-19 16:53:02 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * devops.c: Device operations using the PROM.
3 *
4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5 */
6#include <linux/types.h>
7#include <linux/kernel.h>
8#include <linux/sched.h>
9
10#include <asm/openprom.h>
11#include <asm/oplib.h>
12
13extern void restore_current(void);
14
15/* Open the device described by the string 'dstr'. Returns the handle
16 * to that device used for subsequent operations on that device.
17 * Returns -1 on failure.
18 */
19int
20prom_devopen(char *dstr)
21{
22 int handle;
23 unsigned long flags;
24 spin_lock_irqsave(&prom_lock, flags);
25 switch(prom_vers) {
26 case PROM_V0:
27 handle = (*(romvec->pv_v0devops.v0_devopen))(dstr);
28 if(handle == 0) handle = -1;
29 break;
30 case PROM_V2:
31 case PROM_V3:
32 handle = (*(romvec->pv_v2devops.v2_dev_open))(dstr);
33 break;
34 default:
35 handle = -1;
36 break;
37 };
38 restore_current();
39 spin_unlock_irqrestore(&prom_lock, flags);
40
41 return handle;
42}
43
44/* Close the device described by device handle 'dhandle'. */
45int
46prom_devclose(int dhandle)
47{
48 unsigned long flags;
49 spin_lock_irqsave(&prom_lock, flags);
50 switch(prom_vers) {
51 case PROM_V0:
52 (*(romvec->pv_v0devops.v0_devclose))(dhandle);
53 break;
54 case PROM_V2:
55 case PROM_V3:
56 (*(romvec->pv_v2devops.v2_dev_close))(dhandle);
57 break;
58 default:
59 break;
60 };
61 restore_current();
62 spin_unlock_irqrestore(&prom_lock, flags);
63 return 0;
64}
65
66/* Seek to specified location described by 'seekhi' and 'seeklo'
67 * for device 'dhandle'.
68 */
69void
70prom_seek(int dhandle, unsigned int seekhi, unsigned int seeklo)
71{
72 unsigned long flags;
73 spin_lock_irqsave(&prom_lock, flags);
74 switch(prom_vers) {
75 case PROM_V0:
76 (*(romvec->pv_v0devops.v0_seekdev))(dhandle, seekhi, seeklo);
77 break;
78 case PROM_V2:
79 case PROM_V3:
80 (*(romvec->pv_v2devops.v2_dev_seek))(dhandle, seekhi, seeklo);
81 break;
82 default:
83 break;
84 };
85 restore_current();
86 spin_unlock_irqrestore(&prom_lock, flags);
87
88 return;
89}