diff options
Diffstat (limited to 'kernel/power')
| -rw-r--r-- | kernel/power/console.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/kernel/power/console.c b/kernel/power/console.c index 89bcf4973ee5..b8628be2a465 100644 --- a/kernel/power/console.c +++ b/kernel/power/console.c @@ -7,17 +7,39 @@ #include <linux/vt_kern.h> #include <linux/kbd_kern.h> #include <linux/console.h> +#include <linux/module.h> #include "power.h" #if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) #define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1) static int orig_fgconsole, orig_kmsg; +static int disable_vt_switch; + +/* + * Normally during a suspend, we allocate a new console and switch to it. + * When we resume, we switch back to the original console. This switch + * can be slow, so on systems where the framebuffer can handle restoration + * of video registers anyways, there's little point in doing the console + * switch. This function allows you to disable it by passing it '0'. + */ +void pm_set_vt_switch(int do_switch) +{ + acquire_console_sem(); + disable_vt_switch = !do_switch; + release_console_sem(); +} +EXPORT_SYMBOL(pm_set_vt_switch); int pm_prepare_console(void) { acquire_console_sem(); + if (disable_vt_switch) { + release_console_sem(); + return 0; + } + orig_fgconsole = fg_console; if (vc_allocate(SUSPEND_CONSOLE)) { @@ -50,9 +72,12 @@ int pm_prepare_console(void) void pm_restore_console(void) { acquire_console_sem(); + if (disable_vt_switch) { + release_console_sem(); + return; + } set_console(orig_fgconsole); release_console_sem(); kmsg_redirect = orig_kmsg; - return; } #endif |