lkml.org 
[lkml]   [2014]   [Apr]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC][PATCH 2/3][Resend] PM / runtime: Routine for checking device status during system suspend
Date
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Add a new helper routine, pm_runtime_enabled_and_suspended(), to
allow subsystems (or PM domains) to check the runtime PM status of
devices during system suspend (possibly to avoid resuming those
devices upfront at that time).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/base/power/runtime.c | 28 ++++++++++++++++++++++++++++
include/linux/pm_runtime.h | 2 ++
2 files changed, 30 insertions(+)

Index: linux-pm/include/linux/pm_runtime.h
===================================================================
--- linux-pm.orig/include/linux/pm_runtime.h
+++ linux-pm/include/linux/pm_runtime.h
@@ -57,6 +57,7 @@ extern unsigned long pm_runtime_autosusp
extern void pm_runtime_update_max_time_suspended(struct device *dev,
s64 delta_ns);
extern void pm_runtime_set_memalloc_noio(struct device *dev, bool enable);
+extern bool pm_runtime_enabled_and_suspended(struct device *dev);

static inline bool pm_children_suspended(struct device *dev)
{
@@ -165,6 +166,7 @@ static inline unsigned long pm_runtime_a
struct device *dev) { return 0; }
static inline void pm_runtime_set_memalloc_noio(struct device *dev,
bool enable){}
+static inline bool pm_runtime_enabled_and_suspended(struct device *dev) { return false; }

#endif /* !CONFIG_PM_RUNTIME */

Index: linux-pm/drivers/base/power/runtime.c
===================================================================
--- linux-pm.orig/drivers/base/power/runtime.c
+++ linux-pm/drivers/base/power/runtime.c
@@ -1195,6 +1195,34 @@ void pm_runtime_enable(struct device *de
EXPORT_SYMBOL_GPL(pm_runtime_enable);

/**
+ * pm_runtime_enabled_and_suspended - Check runtime PM status of a device.
+ * @dev: Device to handle.
+ *
+ * This routine is to be executed during system suspend only, after
+ * device_prepare() has been executed for @dev.
+ *
+ * Return false if runtime PM is disabled for the device. Otherwise, wait
+ * for pending transitions to complete and check the runtime PM status of the
+ * device after that. Return true if it is RPM_SUSPENDED.
+ */
+bool pm_runtime_enabled_and_suspended(struct device *dev)
+{
+ unsigned long flags;
+ bool ret;
+
+ spin_lock_irqsave(&dev->power.lock, flags);
+ if (dev->power.disable_depth) {
+ ret = false;
+ } else {
+ __pm_runtime_barrier(dev);
+ ret = pm_runtime_status_suspended(dev);
+ }
+ spin_unlock_irqrestore(&dev->power.lock, flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_enabled_and_suspended);
+
+/**
* pm_runtime_forbid - Block runtime PM of a device.
* @dev: Device to handle.
*

\
 
 \ /
  Last update: 2014-04-25 02:01    [W:0.161 / U:0.448 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site