xref: /freebsd/sys/dev/syscons/blank/blank_saver.c (revision b3e24f9ce91bb200d621c57bfa92eac473a435f9)
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 
40 MOD_MISC(blank_saver);
41 
42 void (*current_saver)(int blank);
43 void (*old_saver)(int blank);
44 
45 static void
46 blank_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 
61 static int
62 blank_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 
71 static int
72 blank_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 
80 int
81 blank_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