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/console.h>
10#include "power.h"
11
12#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
13#define SUSPEND_CONSOLE	(MAX_NR_CONSOLES-1)
14
15static int orig_fgconsole, orig_kmsg;
16
17int pm_prepare_console(void)
18{
19	acquire_console_sem();
20
21	orig_fgconsole = fg_console;
22
23	if (vc_allocate(SUSPEND_CONSOLE)) {
24	  /* we can't have a free VC for now. Too bad,
25	   * we don't want to mess the screen for now. */
26		release_console_sem();
27		return 1;
28	}
29
30	if (set_console(SUSPEND_CONSOLE)) {
31		/*
32		 * We're unable to switch to the SUSPEND_CONSOLE.
33		 * Let the calling function know so it can decide
34		 * what to do.
35		 */
36		release_console_sem();
37		return 1;
38	}
39	release_console_sem();
40
41	if (vt_waitactive(SUSPEND_CONSOLE)) {
42		pr_debug("Suspend: Can't switch VCs.");
43		return 1;
44	}
45	orig_kmsg = kmsg_redirect;
46	kmsg_redirect = SUSPEND_CONSOLE;
47	return 0;
48}
49
50void pm_restore_console(void)
51{
52	acquire_console_sem();
53	set_console(orig_fgconsole);
54	release_console_sem();
55	kmsg_redirect = orig_kmsg;
56	return;
57}
58#endif
59