[PATCH v4] PM / suspend: Export pm_suspend_target_state

From: Florian Fainelli
Date: Mon Jul 17 2017 - 20:19:35 EST


Have the core suspend/resume framework store the system-wide suspend
state (suspend_state_t) we are about to enter, and expose it to drivers
via pm_suspend_target_state in order to retrieve that. The state is
assigned in suspend_devices_and_enter().

This is useful for platform specific drivers that may need to take a
slightly different suspend/resume path based on the system's
suspend/resume state being entered.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
Changes in v4:
- clear pm_suspend_target_state in Close label

Changes in v3:

- just export pm_suspend_target_state without a helper function

Changes in v2:

- rename platform_suspend_target_state() -> suspend_target_state()
- directly export the suspend_state_t value and assign it in
suspend_devices_and_enter()


include/linux/suspend.h | 1 +
kernel/power/suspend.c | 5 +++++
2 files changed, 6 insertions(+)

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 0b1cf32edfd7..2159f6841768 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -427,6 +427,7 @@ extern int unregister_pm_notifier(struct notifier_block *nb);
/* drivers/base/power/wakeup.c */
extern bool events_check_enabled;
extern unsigned int pm_wakeup_irq;
+extern suspend_state_t pm_suspend_target_state;

extern bool pm_wakeup_pending(void);
extern void pm_system_wakeup(void);
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 3ecf275d7e44..d0c0b96c2383 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -47,6 +47,8 @@ const char *mem_sleep_states[PM_SUSPEND_MAX];

suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE;
static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM;
+suspend_state_t pm_suspend_target_state;
+EXPORT_SYMBOL_GPL(pm_suspend_target_state);

unsigned int pm_suspend_global_flags;
EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
@@ -456,6 +458,8 @@ int suspend_devices_and_enter(suspend_state_t state)
if (!sleep_state_supported(state))
return -ENOSYS;

+ pm_suspend_target_state = state;
+
error = platform_suspend_begin(state);
if (error)
goto Close;
@@ -485,6 +489,7 @@ int suspend_devices_and_enter(suspend_state_t state)

Close:
platform_resume_end(state);
+ pm_suspend_target_state = PM_SUSPEND_ON;
return error;

Recover_platform:
--
2.9.3