[PATCH v10 1/5] PM / Runtime: Allow accessing irq_safe if no PM_RUNTIME

From: Krzysztof Kozlowski
Date: Thu Nov 06 2014 - 03:37:16 EST


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.kozlowski@xxxxxxxxxxx>
---
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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