blank_saver.c revision 12276 
1/*-
2 * Copyright (c) 1995 S�ren Schmidt
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software withough specific prior written permission
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 *	$Id: blank_saver.c,v 1.4 1995/11/13 07:18:43 bde Exp $
29 */
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/conf.h>
34#include <sys/exec.h>
35#include <sys/sysent.h>
36#include <sys/lkm.h>
37#include <sys/errno.h>
38#include <saver.h>
39
40MOD_MISC(blank_saver);
41
42void (*current_saver)(int blank);
43void (*old_saver)(int blank);
44
45static void
46blank_saver(int blank)
47{
48	u_char val;
49	if (blank) {
50		scrn_blanked = 1;
51		outb(TSIDX, 0x01); val = inb(TSREG);
52		outb(TSIDX, 0x01); outb(TSREG, val | 0x20);
53	}
54	else {
55		outb(TSIDX, 0x01); val = inb(TSREG);
56		outb(TSIDX, 0x01); outb(TSREG, val & 0xDF);
57		scrn_blanked = 0;
58	}
59}
60
61static int
62blank_saver_load(struct lkm_table *lkmtp, int cmd)
63{
64	(*current_saver)(0);
65	old_saver = current_saver;
66	current_saver = blank_saver;
67	uprintf("blank screen saver installed\n");
68	return 0;
69}
70
71static int
72blank_saver_unload(struct lkm_table *lkmtp, int cmd)
73{
74	(*current_saver)(0);
75	current_saver = old_saver;
76	uprintf("blank screen saver removed\n");
77	return 0;
78}
79
80int
81blank_saver_mod(struct lkm_table *lkmtp, int cmd, int ver)
82{
83	DISPATCH(lkmtp, cmd, ver, blank_saver_load, blank_saver_unload,
84		 lkm_nullcmd);
85}
86