Some drivers (e.g. bus drivers) may want to check if power.irq_safe was
called by child driver, regardless of CONFIG_PM_RUNTIME.

An example scenario is amba/bus.c and dma/pl330.c drivers. The runtime
suspend/resume callbacks in amba bus driver act differently if irq_safe
was set by child driver (in irq_safe mode bus clock is only disabled).

The pl330 driver sets irq_safe and assumes that amba bus driver will
only disable the clock in runtime PM. So in system sleep suspend
callback the pl330 driver unprepares the clock after calling
pm_runtime_force_suspend().

However inconsistency would appear if CONFIG_PM_RUNTIME is not set and
child drivers do not want the irq_safe runtime PM. In such case amba bus
driver still has to know whether child driver wanted irq_safe - by
looking at dev->power.irq_safe field.

Signed-off-by: Krzysztof Kozlowski <k.kozlow...@samsung.com>
---
 include/linux/pm.h         | 2 +-
 include/linux/pm_runtime.h | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 383fd68aaee1..b05fa954f50d 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -566,6 +566,7 @@ struct dev_pm_info {
        bool                    ignore_children:1;
        bool                    early_init:1;   /* Owned by the PM core */
        bool                    direct_complete:1;      /* Owned by the PM core 
*/
+       unsigned int            irq_safe:1;     /* PM runtime */
        spinlock_t              lock;
 #ifdef CONFIG_PM_SLEEP
        struct list_head        entry;
@@ -590,7 +591,6 @@ struct dev_pm_info {
        unsigned int            run_wake:1;
        unsigned int            runtime_auto:1;
        unsigned int            no_callbacks:1;
-       unsigned int            irq_safe:1;
        unsigned int            use_autosuspend:1;
        unsigned int            timer_autosuspends:1;
        unsigned int            memalloc_noio:1;
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index 367f49b9a1c9..d94a65662a60 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -166,7 +166,10 @@ static inline bool pm_runtime_suspended_if_enabled(struct 
device *dev) { return
 static inline bool pm_runtime_enabled(struct device *dev) { return false; }
 
 static inline void pm_runtime_no_callbacks(struct device *dev) {}
-static inline void pm_runtime_irq_safe(struct device *dev) {}
+static inline void pm_runtime_irq_safe(struct device *dev)
+{
+       dev->power.irq_safe = 1;
+}
 
 static inline bool pm_runtime_callbacks_present(struct device *dev) { return 
false; }
 static inline void pm_runtime_mark_last_busy(struct device *dev) {}
-- 
1.9.1

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