Merge branch 'pm-fixes' into fixes

* pm-fixes: cpufreq: Correct header guards typo cpufreq: check OF node /cpus presence before dereferencing it PM / devfreq: Fix compiler warnings for CONFIG_PM_DEVFREQ unset PM / QoS: Avoid possible deadlock related to sysfs access USB / PM: Don't try to hide PM QoS flags from usb_port_device_release()
mariux64 · Apr 4, 2013 · 6cb437a · 6cb437a
2 parents fc1a7fe + beb0ff3
commit 6cb437a
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Showing 5 changed files with 66 additions and 27 deletions.
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
@@ -46,6 +46,7 @@
 #include "power.h"
 
 static DEFINE_MUTEX(dev_pm_qos_mtx);
+static DEFINE_MUTEX(dev_pm_qos_sysfs_mtx);
 
 static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers);
 
@@ -216,12 +217,17 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
 	struct pm_qos_constraints *c;
 	struct pm_qos_flags *f;
 
-	mutex_lock(&dev_pm_qos_mtx);
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
 
 	/*
 	 * If the device's PM QoS resume latency limit or PM QoS flags have been
 	 * exposed to user space, they have to be hidden at this point.
 	 */
+	pm_qos_sysfs_remove_latency(dev);
+	pm_qos_sysfs_remove_flags(dev);
+
+	mutex_lock(&dev_pm_qos_mtx);
+
 	__dev_pm_qos_hide_latency_limit(dev);
 	__dev_pm_qos_hide_flags(dev);
 
@@ -254,6 +260,8 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
 
  out:
 	mutex_unlock(&dev_pm_qos_mtx);
+
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
 }
 
 /**
@@ -558,6 +566,14 @@ static void __dev_pm_qos_drop_user_request(struct device *dev,
 	kfree(req);
 }
 
+static void dev_pm_qos_drop_user_request(struct device *dev,
+					 enum dev_pm_qos_req_type type)
+{
+	mutex_lock(&dev_pm_qos_mtx);
+	__dev_pm_qos_drop_user_request(dev, type);
+	mutex_unlock(&dev_pm_qos_mtx);
+}
+
 /**
  * dev_pm_qos_expose_latency_limit - Expose PM QoS latency limit to user space.
  * @dev: Device whose PM QoS latency limit is to be exposed to user space.
@@ -581,6 +597,8 @@ int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
 		return ret;
 	}
 
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+
 	mutex_lock(&dev_pm_qos_mtx);
 
 	if (IS_ERR_OR_NULL(dev->power.qos))
@@ -591,26 +609,27 @@ int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
 	if (ret < 0) {
 		__dev_pm_qos_remove_request(req);
 		kfree(req);
+		mutex_unlock(&dev_pm_qos_mtx);
 		goto out;
 	}
-
 	dev->power.qos->latency_req = req;
+
+	mutex_unlock(&dev_pm_qos_mtx);
+
 	ret = pm_qos_sysfs_add_latency(dev);
 	if (ret)
-		__dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY);
+		dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY);
 
  out:
-	mutex_unlock(&dev_pm_qos_mtx);
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_limit);
 
 static void __dev_pm_qos_hide_latency_limit(struct device *dev)
 {
-	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->latency_req) {
-		pm_qos_sysfs_remove_latency(dev);
+	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->latency_req)
 		__dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY);
-	}
 }
 
 /**
@@ -619,9 +638,15 @@ static void __dev_pm_qos_hide_latency_limit(struct device *dev)
  */
 void dev_pm_qos_hide_latency_limit(struct device *dev)
 {
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+
+	pm_qos_sysfs_remove_latency(dev);
+
 	mutex_lock(&dev_pm_qos_mtx);
 	__dev_pm_qos_hide_latency_limit(dev);
 	mutex_unlock(&dev_pm_qos_mtx);
+
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
 }
 EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_limit);
 
@@ -649,6 +674,8 @@ int dev_pm_qos_expose_flags(struct device *dev, s32 val)
 	}
 
 	pm_runtime_get_sync(dev);
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+
 	mutex_lock(&dev_pm_qos_mtx);
 
 	if (IS_ERR_OR_NULL(dev->power.qos))
@@ -659,27 +686,28 @@ int dev_pm_qos_expose_flags(struct device *dev, s32 val)
 	if (ret < 0) {
 		__dev_pm_qos_remove_request(req);
 		kfree(req);
+		mutex_unlock(&dev_pm_qos_mtx);
 		goto out;
 	}
-
 	dev->power.qos->flags_req = req;
+
+	mutex_unlock(&dev_pm_qos_mtx);
+
 	ret = pm_qos_sysfs_add_flags(dev);
 	if (ret)
-		__dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS);
+		dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS);
 
  out:
-	mutex_unlock(&dev_pm_qos_mtx);
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
 	pm_runtime_put(dev);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dev_pm_qos_expose_flags);
 
 static void __dev_pm_qos_hide_flags(struct device *dev)
 {
-	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req) {
-		pm_qos_sysfs_remove_flags(dev);
+	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req)
 		__dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS);
-	}
 }
 
 /**
@@ -689,9 +717,15 @@ static void __dev_pm_qos_hide_flags(struct device *dev)
 void dev_pm_qos_hide_flags(struct device *dev)
 {
 	pm_runtime_get_sync(dev);
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+
+	pm_qos_sysfs_remove_flags(dev);
+
 	mutex_lock(&dev_pm_qos_mtx);
 	__dev_pm_qos_hide_flags(dev);
 	mutex_unlock(&dev_pm_qos_mtx);
+
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
 	pm_runtime_put(dev);
 }
 EXPORT_SYMBOL_GPL(dev_pm_qos_hide_flags);

diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
@@ -178,10 +178,16 @@ static struct cpufreq_driver cpu0_cpufreq_driver = {
 
 static int cpu0_cpufreq_probe(struct platform_device *pdev)
 {
-	struct device_node *np;
+	struct device_node *np, *parent;
 	int ret;
 
-	for_each_child_of_node(of_find_node_by_path("/cpus"), np) {
+	parent = of_find_node_by_path("/cpus");
+	if (!parent) {
+		pr_err("failed to find OF /cpus\n");
+		return -ENOENT;
+	}
+
+	for_each_child_of_node(parent, np) {
 		if (of_get_property(np, "operating-points", NULL))
 			break;
 	}

diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
@@ -14,8 +14,8 @@
  * published by the Free Software Foundation.
  */
 
-#ifndef _CPUFREQ_GOVERNER_H
-#define _CPUFREQ_GOVERNER_H
+#ifndef _CPUFREQ_GOVERNOR_H
+#define _CPUFREQ_GOVERNOR_H
 
 #include <linux/cpufreq.h>
 #include <linux/kobject.h>
@@ -175,4 +175,4 @@ bool need_load_eval(struct cpu_dbs_common_info *cdbs,
 		unsigned int sampling_rate);
 int cpufreq_governor_dbs(struct dbs_data *dbs_data,
 		struct cpufreq_policy *policy, unsigned int event);
-#endif /* _CPUFREQ_GOVERNER_H */
+#endif /* _CPUFREQ_GOVERNOR_H */
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
@@ -67,7 +67,6 @@ static void usb_port_device_release(struct device *dev)
 {
 	struct usb_port *port_dev = to_usb_port(dev);
 
-	dev_pm_qos_hide_flags(dev);
 	kfree(port_dev);
 }
 

diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
@@ -213,42 +213,42 @@ struct devfreq_simple_ondemand_data {
 #endif
 
 #else /* !CONFIG_PM_DEVFREQ */
-static struct devfreq *devfreq_add_device(struct device *dev,
+static inline struct devfreq *devfreq_add_device(struct device *dev,
 					  struct devfreq_dev_profile *profile,
 					  const char *governor_name,
 					  void *data)
 {
 	return NULL;
 }
 
-static int devfreq_remove_device(struct devfreq *devfreq)
+static inline int devfreq_remove_device(struct devfreq *devfreq)
 {
 	return 0;
 }
 
-static int devfreq_suspend_device(struct devfreq *devfreq)
+static inline int devfreq_suspend_device(struct devfreq *devfreq)
 {
 	return 0;
 }
 
-static int devfreq_resume_device(struct devfreq *devfreq)
+static inline int devfreq_resume_device(struct devfreq *devfreq)
 {
 	return 0;
 }
 
-static struct opp *devfreq_recommended_opp(struct device *dev,
+static inline struct opp *devfreq_recommended_opp(struct device *dev,
 					   unsigned long *freq, u32 flags)
 {
-	return -EINVAL;
+	return ERR_PTR(-EINVAL);
 }
 
-static int devfreq_register_opp_notifier(struct device *dev,
+static inline int devfreq_register_opp_notifier(struct device *dev,
 					 struct devfreq *devfreq)
 {
 	return -EINVAL;
 }
 
-static int devfreq_unregister_opp_notifier(struct device *dev,
+static inline int devfreq_unregister_opp_notifier(struct device *dev,
 					   struct devfreq *devfreq)
 {
 	return -EINVAL;