Introduce CONFIG_SUSPEND for suspend-to-Ram and standby

Introduce CONFIG_SUSPEND representing the ability to enter system sleep
states, such as the ACPI S3 state, and allow the user to choose SUSPEND
and HIBERNATION independently of each other.

Make HOTPLUG_CPU be selected automatically if SUSPEND or HIBERNATION has
been chosen and the kernel is intended for SMP systems.

Also, introduce CONFIG_PM_SLEEP which is automatically selected if
CONFIG_SUSPEND or CONFIG_HIBERNATION is set and use it to select the
code needed for both suspend and hibernation.

The top-level power management headers and the ACPI code related to
suspend and hibernation are modified to use the new definitions (the
changes in drivers/acpi/sleep/main.c are, mostly, moving code to reduce
the number of ifdefs).

There are many other files in which CONFIG_PM can be replaced with
CONFIG_PM_SLEEP or even with CONFIG_SUSPEND, but they can be updated in
the future.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 19 insertions, 12 deletions

diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index c8e02de737f..efded00ad08 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -5,7 +5,7 @@
 
 #include <linux/sched.h>
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 /*
  * Check if a process has been frozen
  */
@@ -126,7 +126,7 @@ static inline void set_freezable(void)
 	current->flags &= ~PF_NOFREEZE;
 }
 
-#else
+#else /* !CONFIG_PM_SLEEP */
 static inline int frozen(struct task_struct *p) { return 0; }
 static inline int freezing(struct task_struct *p) { return 0; }
 static inline void set_freeze_flag(struct task_struct *p) {}
@@ -143,6 +143,6 @@ static inline void freezer_do_not_count(void) {}
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
-#endif
+#endif /* !CONFIG_PM_SLEEP */
 
 #endif	/* FREEZER_H_INCLUDED */
diff --git a/include/linux/pm.h b/include/linux/pm.h
index ad3cc2eb0d3..e52f6f83c06 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -165,6 +165,7 @@ struct pm_ops {
 	int (*finish)(suspend_state_t state);
 };
 
+#ifdef CONFIG_SUSPEND
 extern struct pm_ops *pm_ops;
 
 /**
@@ -193,6 +194,12 @@ extern void arch_suspend_disable_irqs(void);
 extern void arch_suspend_enable_irqs(void);
 
 extern int pm_suspend(suspend_state_t state);
+#else /* !CONFIG_SUSPEND */
+#define suspend_valid_only_mem	NULL
+
+static inline void pm_set_ops(struct pm_ops *pm_ops) {}
+static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
+#endif /* !CONFIG_SUSPEND */
 
 /*
  * Device power management
@@ -266,7 +273,7 @@ typedef struct pm_message {
 struct dev_pm_info {
 	pm_message_t		power_state;
 	unsigned		can_wakeup:1;
-#ifdef	CONFIG_PM
+#ifdef	CONFIG_PM_SLEEP
 	unsigned		should_wakeup:1;
 	struct list_head	entry;
 #endif
@@ -276,7 +283,7 @@ extern int device_power_down(pm_message_t state);
 extern void device_power_up(void);
 extern void device_resume(void);
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 extern int device_suspend(pm_message_t state);
 extern int device_prepare_suspend(pm_message_t state);
 
@@ -306,7 +313,7 @@ static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
 	return 0;
 }
 
-#else /* !CONFIG_PM */
+#else /* !CONFIG_PM_SLEEP */
 
 static inline int device_suspend(pm_message_t state)
 {
@@ -323,7 +330,7 @@ static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
 	return 0;
 }
 
-#endif
+#endif /* !CONFIG_PM_SLEEP */
 
 /* changes to device_may_wakeup take effect on the next pm state change.
  * by default, devices should wakeup if they can.
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index d16c1b85d51..388cace9751 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -24,7 +24,7 @@ struct pbe {
 extern void drain_local_pages(void);
 extern void mark_free_pages(struct zone *zone);
 
-#if defined(CONFIG_PM) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
+#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
 extern int pm_prepare_console(void);
 extern void pm_restore_console(void);
 #else
@@ -54,7 +54,6 @@ struct hibernation_ops {
 	void (*restore_cleanup)(void);
 };
 
-#ifdef CONFIG_PM
 #ifdef CONFIG_HIBERNATION
 /* kernel/power/snapshot.c */
 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
@@ -82,6 +81,7 @@ static inline void hibernation_set_ops(struct hibernation_ops *ops) {}
 static inline int hibernate(void) { return -ENOSYS; }
 #endif /* CONFIG_HIBERNATION */
 
+#ifdef CONFIG_PM_SLEEP
 void save_processor_state(void);
 void restore_processor_state(void);
 struct saved_context;
@@ -106,7 +106,7 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 		{ .notifier_call = fn, .priority = pri };	\
 	register_pm_notifier(&fn##_nb);			\
 }
-#else /* CONFIG_PM */
+#else /* !CONFIG_PM_SLEEP */
 
 static inline int register_pm_notifier(struct notifier_block *nb)
 {
@@ -119,9 +119,9 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 }
 
 #define pm_notifier(fn, pri)	do { (void)(fn); } while (0)
-#endif /* CONFIG_PM */
+#endif /* !CONFIG_PM_SLEEP */
 
-#if !defined CONFIG_HIBERNATION || !defined(CONFIG_PM)
+#ifndef CONFIG_HIBERNATION
 static inline void register_nosave_region(unsigned long b, unsigned long e)
 {
 }