From abfe2d7b915c872f3a1fd203267cedebf90daa45 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 19 Jan 2009 20:54:54 +0100 Subject: [PATCH] Hibernation: Introduce system_entering_hibernation Introduce boolean function system_entering_hibernation() returning 'true' during the last phase of hibernation, in which devices are being put into low power states and the sleep state (for example, ACPI S4) is finally entered. Some device drivers need such a function to check if the system is in the final phase of hibernation. In particular, some SATA drivers are going to use it for blacklisting systems in which the disks should not be spun down during the last phase of hibernation (the BIOS will do that anyway). Signed-off-by: Rafael J. Wysocki Signed-off-by: Jeff Garzik --- include/linux/suspend.h | 2 ++ kernel/power/disk.c | 10 ++++++++++ 2 files changed, 12 insertions(+) diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 2b409c44db8..c7d9bb1832b 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -237,6 +237,7 @@ extern int hibernate_nvs_alloc(void); extern void hibernate_nvs_free(void); extern void hibernate_nvs_save(void); extern void hibernate_nvs_restore(void); +extern bool system_entering_hibernation(void); #else /* CONFIG_HIBERNATION */ static inline int swsusp_page_is_forbidden(struct page *p) { return 0; } static inline void swsusp_set_page_free(struct page *p) {} @@ -252,6 +253,7 @@ static inline int hibernate_nvs_alloc(void) { return 0; } static inline void hibernate_nvs_free(void) {} static inline void hibernate_nvs_save(void) {} static inline void hibernate_nvs_restore(void) {} +static inline bool system_entering_hibernation(void) { return false; } #endif /* CONFIG_HIBERNATION */ #ifdef CONFIG_PM_SLEEP diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 45e8541ab7e..432ee575c9e 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -71,6 +71,14 @@ void hibernation_set_ops(struct platform_hibernation_ops *ops) mutex_unlock(&pm_mutex); } +static bool entering_platform_hibernation; + +bool system_entering_hibernation(void) +{ + return entering_platform_hibernation; +} +EXPORT_SYMBOL(system_entering_hibernation); + #ifdef CONFIG_PM_DEBUG static void hibernation_debug_sleep(void) { @@ -411,6 +419,7 @@ int hibernation_platform_enter(void) if (error) goto Close; + entering_platform_hibernation = true; suspend_console(); error = device_suspend(PMSG_HIBERNATE); if (error) { @@ -445,6 +454,7 @@ int hibernation_platform_enter(void) Finish: hibernation_ops->finish(); Resume_devices: + entering_platform_hibernation = false; device_resume(PMSG_RESTORE); resume_console(); Close: -- 2.41.1