xref: /openbmc/linux/kernel/power/console.c (revision 25985edc)
1 /*
2  * drivers/power/process.c - Functions for saving/restoring console.
3  *
4  * Originally from swsusp.
5  */
6 
7 #include <linux/vt_kern.h>
8 #include <linux/kbd_kern.h>
9 #include <linux/vt.h>
10 #include <linux/module.h>
11 #include "power.h"
12 
13 #if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
14 #define SUSPEND_CONSOLE	(MAX_NR_CONSOLES-1)
15 
16 static int orig_fgconsole, orig_kmsg;
17 
18 int pm_prepare_console(void)
19 {
20 	orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1);
21 	if (orig_fgconsole < 0)
22 		return 1;
23 
24 	orig_kmsg = vt_kmsg_redirect(SUSPEND_CONSOLE);
25 	return 0;
26 }
27 
28 void pm_restore_console(void)
29 {
30 	if (orig_fgconsole >= 0) {
31 		vt_move_to_console(orig_fgconsole, 0);
32 		vt_kmsg_redirect(orig_kmsg);
33 	}
34 }
35 #endif
36