PM / Domains: Move syscore flag from subsys data to struct device

The syscore device PM flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages.  That flag is
stored in the device's struct pm_subsys_data object whose address is
available from struct device.  However, in some situations it may be
convenient to set that flag before the device is added to a PM
domain, so it is better to move it directly to the "power" member of
struct device.  Then, it can be checked by the routines in
drivers/base/power/runtime.c and drivers/base/power/main.c, which is
more straightforward.

This also reduces the number of dev_gpd_data() invocations in the
generic PM domains framework, so the overhead related to the syscore
flag is slightly smaller.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

drivers/base/power/common.c

@@ -83,3 +83,18 @@ int dev_pm_put_subsys_data(struct device *dev)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data);
+
+/**
+ * dev_pm_syscore_device - Set/unset the given device's power.syscore flag.
+ * @dev: Device whose flag is to be modified.
+ * @val: New value of the flag.
+ */
+void dev_pm_syscore_device(struct device *dev, bool val)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+	dev->power.syscore = val;
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+}
+EXPORT_SYMBOL_GPL(dev_pm_syscore_device);

drivers/base/power/domain.c

@@ -436,7 +436,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
 	not_suspended = 0;
 	list_for_each_entry(pdd, &genpd->dev_list, list_node)
 		if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
-		    || pdd->dev->power.irq_safe || to_gpd_data(pdd)->syscore))
+		    || pdd->dev->power.irq_safe || pdd->dev->power.syscore))
 			not_suspended++;
 
 	if (not_suspended > genpd->in_progress)
@@ -578,9 +578,6 @@ static int pm_genpd_runtime_suspend(struct device *dev)
 
 	might_sleep_if(!genpd->dev_irq_safe);
 
-	if (dev_gpd_data(dev)->syscore)
-		return -EBUSY;
-
 	stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
 	if (stop_ok && !stop_ok(dev))
 		return -EBUSY;
@@ -983,7 +980,7 @@ static int pm_genpd_suspend_noirq(struct device *dev)
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (genpd->suspend_power_off || dev_gpd_data(dev)->syscore
+	if (genpd->suspend_power_off
 	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
 		return 0;
 
@@ -1016,7 +1013,7 @@ static int pm_genpd_resume_noirq(struct device *dev)
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	if (genpd->suspend_power_off || dev_gpd_data(dev)->syscore
+	if (genpd->suspend_power_off
 	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
 		return 0;
 
@@ -1136,8 +1133,7 @@ static int pm_genpd_freeze_noirq(struct device *dev)
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	return genpd->suspend_power_off || dev_gpd_data(dev)->syscore ?
-		0 : genpd_stop_dev(genpd, dev);
+	return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
 }
 
 /**
@@ -1157,8 +1153,7 @@ static int pm_genpd_thaw_noirq(struct device *dev)
 	if (IS_ERR(genpd))
 		return -EINVAL;
 
-	return genpd->suspend_power_off || dev_gpd_data(dev)->syscore ?
-		0 : genpd_start_dev(genpd, dev);
+	return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
 }
 
 /**
@@ -1253,7 +1248,7 @@ static int pm_genpd_restore_noirq(struct device *dev)
 
 	pm_genpd_sync_poweron(genpd);
 
-	return dev_gpd_data(dev)->syscore ? 0 : genpd_start_dev(genpd, dev);
+	return genpd_start_dev(genpd, dev);
 }
 
 /**
@@ -1525,26 +1520,6 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 	return ret;
 }
 
-/**
- * pm_genpd_dev_syscore - Set/unset the "syscore" flag for a given device.
- * @dev: Device to set/unset the flag for.
- * @val: The new value of the device's "syscore" flag.
- */
-void pm_genpd_dev_syscore(struct device *dev, bool val)
-{
-	struct pm_subsys_data *psd;
-	unsigned long flags;
-
-	spin_lock_irqsave(&dev->power.lock, flags);
-
-	psd = dev_to_psd(dev);
-	if (psd && psd->domain_data)
-		to_gpd_data(psd->domain_data)->syscore = val;
-
-	spin_unlock_irqrestore(&dev->power.lock, flags);
-}
-EXPORT_SYMBOL_GPL(pm_genpd_dev_syscore);
-
 /**
  * pm_genpd_dev_need_restore - Set/unset the device's "need restore" flag.
  * @dev: Device to set/unset the flag for.

drivers/base/power/main.c

@@ -405,6 +405,9 @@ static int device_resume_noirq(struct device *dev, pm_message_t state)
 	TRACE_DEVICE(dev);
 	TRACE_RESUME(0);
 
+	if (dev->power.syscore)
+		goto Out;
+
 	if (dev->pm_domain) {
 		info = "noirq power domain ";
 		callback = pm_noirq_op(&dev->pm_domain->ops, state);
@@ -426,6 +429,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state)
 
 	error = dpm_run_callback(callback, dev, state, info);
 
+ Out:
 	TRACE_RESUME(error);
 	return error;
 }
@@ -483,6 +487,9 @@ static int device_resume_early(struct device *dev, pm_message_t state)
 	TRACE_DEVICE(dev);
 	TRACE_RESUME(0);
 
+	if (dev->power.syscore)
+		goto Out;
+
 	if (dev->pm_domain) {
 		info = "early power domain ";
 		callback = pm_late_early_op(&dev->pm_domain->ops, state);
@@ -504,6 +511,7 @@ static int device_resume_early(struct device *dev, pm_message_t state)
 
 	error = dpm_run_callback(callback, dev, state, info);
 
+ Out:
 	TRACE_RESUME(error);
 	return error;
 }
@@ -567,6 +575,9 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
 	TRACE_DEVICE(dev);
 	TRACE_RESUME(0);
 
+	if (dev->power.syscore)
+		goto Complete;
+
 	dpm_wait(dev->parent, async);
 	device_lock(dev);
 
@@ -629,6 +640,8 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
 
  Unlock:
 	device_unlock(dev);
+
+ Complete:
 	complete_all(&dev->power.completion);
 
 	TRACE_RESUME(error);
@@ -719,6 +732,9 @@ static void device_complete(struct device *dev, pm_message_t state)
 	void (*callback)(struct device *) = NULL;
 	char *info = NULL;
 
+	if (dev->power.syscore)
+		return;
+
 	device_lock(dev);
 
 	if (dev->pm_domain) {
@@ -831,6 +847,9 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state)
 	pm_callback_t callback = NULL;
 	char *info = NULL;
 
+	if (dev->power.syscore)
+		return 0;
+
 	if (dev->pm_domain) {
 		info = "noirq power domain ";
 		callback = pm_noirq_op(&dev->pm_domain->ops, state);
@@ -914,6 +933,9 @@ static int device_suspend_late(struct device *dev, pm_message_t state)
 	pm_callback_t callback = NULL;
 	char *info = NULL;
 
+	if (dev->power.syscore)
+		return 0;
+
 	if (dev->pm_domain) {
 		info = "late power domain ";
 		callback = pm_late_early_op(&dev->pm_domain->ops, state);
@@ -1050,6 +1072,9 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 		goto Complete;
 	}
 
+	if (dev->power.syscore)
+		goto Complete;
+
 	device_lock(dev);
 
 	if (dev->pm_domain) {
@@ -1206,6 +1231,9 @@ static int device_prepare(struct device *dev, pm_message_t state)
 	char *info = NULL;
 	int error = 0;
 
+	if (dev->power.syscore)
+		return 0;
+
 	device_lock(dev);
 
 	dev->power.wakeup_path = device_may_wakeup(dev);

drivers/base/power/runtime.c

@@ -134,7 +134,7 @@ static int rpm_check_suspend_allowed(struct device *dev)
 
 	if (dev->power.runtime_error)
 		retval = -EINVAL;
-	else if (dev->power.disable_depth > 0)
+	else if (dev->power.disable_depth > 0 || dev->power.syscore)
 		retval = -EACCES;
 	else if (atomic_read(&dev->power.usage_count) > 0)
 		retval = -EAGAIN;

drivers/clocksource/sh_cmt.c

@@ -717,7 +717,7 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
 		struct sh_timer_config *cfg = pdev->dev.platform_data;
 
 		if (cfg->clocksource_rating || cfg->clockevent_rating)
-			pm_genpd_dev_syscore(&pdev->dev, true);
+			dev_pm_syscore_device(&pdev->dev, true);
 	}
 
 	if (p) {

drivers/clocksource/sh_mtu2.c

@@ -323,7 +323,7 @@ static int __devinit sh_mtu2_probe(struct platform_device *pdev)
 		struct sh_timer_config *cfg = pdev->dev.platform_data;
 
 		if (cfg->clockevent_rating)
-			pm_genpd_dev_syscore(&pdev->dev, true);
+			dev_pm_syscore_device(&pdev->dev, true);
 	}
 
 	if (p) {

drivers/clocksource/sh_tmu.c

@@ -453,7 +453,7 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev)
 		struct sh_timer_config *cfg = pdev->dev.platform_data;
 
 		if (cfg->clocksource_rating || cfg->clockevent_rating)
-			pm_genpd_dev_syscore(&pdev->dev, true);
+			dev_pm_syscore_device(&pdev->dev, true);
 	}
 
 	if (p) {

include/linux/pm.h

@@ -43,8 +43,12 @@ struct device;
 
 #ifdef CONFIG_PM
 extern const char power_group_name[];		/* = "power" */
+
+extern void dev_pm_syscore_device(struct device *dev, bool val);
 #else
 #define power_group_name	NULL
+
+static inline void dev_pm_syscore_device(struct device *dev, bool val) {}
 #endif
 
 typedef struct pm_message {
@@ -511,6 +515,7 @@ struct dev_pm_info {
 	bool			is_suspended:1;	/* Ditto */
 	bool			ignore_children:1;
 	bool			early_init:1;	/* Owned by the PM core */
+	bool			syscore:1;
 	spinlock_t		lock;
 #ifdef CONFIG_PM_SLEEP
 	struct list_head	entry;

include/linux/pm_domain.h

@@ -114,7 +114,6 @@ struct generic_pm_domain_data {
 	struct mutex lock;
 	unsigned int refcount;
 	bool need_restore;
-	bool syscore;
 };
 
 #ifdef CONFIG_PM_GENERIC_DOMAINS
@@ -153,7 +152,6 @@ static inline int pm_genpd_of_add_device(struct device_node *genpd_node,
 
 extern int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 				  struct device *dev);
-extern void pm_genpd_dev_syscore(struct device *dev, bool val);
 extern void pm_genpd_dev_need_restore(struct device *dev, bool val);
 extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 				  struct generic_pm_domain *new_subdomain);
@@ -199,7 +197,6 @@ static inline int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 {
 	return -ENOSYS;
 }
-static inline void pm_genpd_dev_syscore(struct device *dev, bool val) {}
 static inline void pm_genpd_dev_need_restore(struct device *dev, bool val) {}
 static inline int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 					 struct generic_pm_domain *new_sd)