PM: Move definition of struct pm_ops to suspend.h

Move the definition of 'struct pm_ops' and related functions from <linux/pm.h>
to <linux/suspend.h> .

There are, at least, the following reasons to do that:
* 'struct pm_ops' is specifically related to suspend and not to the power
  management in general.
* As long as 'struct pm_ops' is defined in <linux/pm.h>, any modification of it
  causes the entire kernel to be recompiled, which is unnecessary and annoying.
* Some suspend-related features are already defined in <linux/suspend.h>, so it
  is logical to move the definition of 'struct pm_ops' into there.
* 'struct hibernation_ops', being the hibernation-related counterpart of
  'struct pm_ops', is defined in <linux/suspend.h> .

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 110 insertions, 11 deletions

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 388cace9751..c230680d525 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -1,5 +1,5 @@
-#ifndef _LINUX_SWSUSP_H
-#define _LINUX_SWSUSP_H
+#ifndef _LINUX_SUSPEND_H
+#define _LINUX_SUSPEND_H
 
 #if defined(CONFIG_X86) || defined(CONFIG_FRV) || defined(CONFIG_PPC32) || defined(CONFIG_PPC64)
 #include <asm/suspend.h>
@@ -9,6 +9,113 @@
 #include <linux/init.h>
 #include <linux/pm.h>
 #include <linux/mm.h>
+#include <asm/errno.h>
+
+#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
+static inline int pm_prepare_console(void) { return 0; }
+static inline void pm_restore_console(void) {}
+#endif
+
+typedef int __bitwise suspend_state_t;
+
+#define PM_SUSPEND_ON		((__force suspend_state_t) 0)
+#define PM_SUSPEND_STANDBY	((__force suspend_state_t) 1)
+#define PM_SUSPEND_MEM		((__force suspend_state_t) 3)
+#define PM_SUSPEND_MAX		((__force suspend_state_t) 4)
+
+/**
+ * struct pm_ops - Callbacks for managing platform dependent system sleep
+ *	states.
+ *
+ * @valid: Callback to determine if given system sleep state is supported by
+ *	the platform.
+ *	Valid (ie. supported) states are advertised in /sys/power/state.  Note
+ *	that it still may be impossible to enter given system sleep state if the
+ *	conditions aren't right.
+ *	There is the %pm_valid_only_mem function available that can be assigned
+ *	to this if the platform only supports mem sleep.
+ *
+ * @set_target: Tell the platform which system sleep state is going to be
+ *	entered.
+ *	@set_target() is executed right prior to suspending devices.  The
+ *	information conveyed to the platform code by @set_target() should be
+ *	disregarded by the platform as soon as @finish() is executed and if
+ *	@prepare() fails.  If @set_target() fails (ie. returns nonzero),
+ *	@prepare(), @enter() and @finish() will not be called by the PM core.
+ *	This callback is optional.  However, if it is implemented, the argument
+ *	passed to @prepare(), @enter() and @finish() is meaningless and should
+ *	be ignored.
+ *
+ * @prepare: Prepare the platform for entering the system sleep state indicated
+ *	by @set_target() or represented by the argument if @set_target() is not
+ *	implemented.
+ *	@prepare() is called right after devices have been suspended (ie. the
+ *	appropriate .suspend() method has been executed for each device) and
+ *	before the nonboot CPUs are disabled (it is executed with IRQs enabled).
+ *	This callback is optional.  It returns 0 on success or a negative
+ *	error code otherwise, in which case the system cannot enter the desired
+ *	sleep state (@enter() and @finish() will not be called in that case).
+ *
+ * @enter: Enter the system sleep state indicated by @set_target() or
+ *	represented by the argument if @set_target() is not implemented.
+ *	This callback is mandatory.  It returns 0 on success or a negative
+ *	error code otherwise, in which case the system cannot enter the desired
+ *	sleep state.
+ *
+ * @finish: Called when the system has just left a sleep state, right after
+ *	the nonboot CPUs have been enabled and before devices are resumed (it is
+ *	executed with IRQs enabled).  If @set_target() is not implemented, the
+ *	argument represents the sleep state being left.
+ *	This callback is optional, but should be implemented by the platforms
+ *	that implement @prepare().  If implemented, it is always called after
+ *	@enter() (even if @enter() fails).
+ */
+struct pm_ops {
+	int (*valid)(suspend_state_t state);
+	int (*set_target)(suspend_state_t state);
+	int (*prepare)(suspend_state_t state);
+	int (*enter)(suspend_state_t state);
+	int (*finish)(suspend_state_t state);
+};
+
+#ifdef CONFIG_SUSPEND
+extern struct pm_ops *pm_ops;
+
+/**
+ * pm_set_ops - set platform dependent power management ops
+ * @pm_ops: The new power management operations to set.
+ */
+extern void pm_set_ops(struct pm_ops *pm_ops);
+extern int pm_valid_only_mem(suspend_state_t state);
+
+/**
+ * arch_suspend_disable_irqs - disable IRQs for suspend
+ *
+ * Disables IRQs (in the default case). This is a weak symbol in the common
+ * code and thus allows architectures to override it if more needs to be
+ * done. Not called for suspend to disk.
+ */
+extern void arch_suspend_disable_irqs(void);
+
+/**
+ * arch_suspend_enable_irqs - enable IRQs after suspend
+ *
+ * Enables IRQs (in the default case). This is a weak symbol in the common
+ * code and thus allows architectures to override it if more needs to be
+ * done. Not called for suspend to disk.
+ */
+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 */
 
 /* struct pbe is used for creating lists of pages that should be restored
  * atomically during the resume from disk, because the page frames they have
@@ -24,14 +131,6 @@ struct pbe {
 extern void drain_local_pages(void);
 extern void mark_free_pages(struct zone *zone);
 
-#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
-static inline int pm_prepare_console(void) { return 0; }
-static inline void pm_restore_console(void) {}
-#endif
-
 /**
  * struct hibernation_ops - hibernation platform support
  *
@@ -130,4 +229,4 @@ static inline void register_nosave_region_late(unsigned long b, unsigned long e)
 }
 #endif
 
-#endif /* _LINUX_SWSUSP_H */
+#endif /* _LINUX_SUSPEND_H */