From 585fc83ece43be63d5775e536f855db33dd752cf Mon Sep 17 00:00:00 2001
From: Chanwoo Choi <cw00.choi@samsung.com>
Date: Fri, 9 May 2014 16:43:07 +0900
Subject: PM / devfreq: Fix devfreq_remove_device() to improve the sequence of
 resource free

This patch modify devfreq_remove_device() to improve the sequence of resource
free. If executing existing devfreq_remove_device(), this function always
executes _remove_devfreq() twice. In result, second _remove_devfreq() always
return error value. So, This patch resolves complicated function sequence
as following:

[Flow sequence before modification]
devfreq_remove_device()
   _remove_devfreq(devfreq, false)
      kfree(devfreq);  /* Free devfreq */
      if (!skip ...) { /* skip is false */
         device_unregister(&devfreq->dev)
         put_device(&devfreq->dev);
            ...
            dev->release()
               devfreq_dev_release()
                  _remove_devfreq(devfreq, true) <- Recall to free devfreq
                  /*
		   * Always return error without freeing resource because
		   * already _remove_devfreq() frees the memory of devfreq.
		   */
   }

[Flow sequence after modification]
devfreq_remove_device
   device_unregister(&devfreq->dev)
   put_device(&devfreq->dev);
      ..
      dev->release()
         devfreq_dev_release()
            _remove_devfreq()
               kfree(devfreq); /* Free devfreq */

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
[Merge conflict resolved by MyungJoo]
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
---
 drivers/devfreq/devfreq.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

(limited to 'drivers/devfreq/devfreq.c')

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2042ec3656b..af4af770857 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -394,7 +394,7 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type,
  * @devfreq:	the devfreq struct
  * @skip:	skip calling device_unregister().
  */
-static void _remove_devfreq(struct devfreq *devfreq, bool skip)
+static void _remove_devfreq(struct devfreq *devfreq)
 {
 	mutex_lock(&devfreq_list_lock);
 	if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) {
@@ -412,11 +412,6 @@ static void _remove_devfreq(struct devfreq *devfreq, bool skip)
 	if (devfreq->profile->exit)
 		devfreq->profile->exit(devfreq->dev.parent);
 
-	if (!skip && get_device(&devfreq->dev)) {
-		device_unregister(&devfreq->dev);
-		put_device(&devfreq->dev);
-	}
-
 	mutex_destroy(&devfreq->lock);
 	kfree(devfreq);
 }
@@ -426,14 +421,12 @@ static void _remove_devfreq(struct devfreq *devfreq, bool skip)
  * @dev:	the devfreq device
  *
  * This calls _remove_devfreq() if _remove_devfreq() is not called.
- * Note that devfreq_dev_release() could be called by _remove_devfreq() as
- * well as by others unregistering the device.
  */
 static void devfreq_dev_release(struct device *dev)
 {
 	struct devfreq *devfreq = to_devfreq(dev);
 
-	_remove_devfreq(devfreq, true);
+	_remove_devfreq(devfreq);
 }
 
 /**
@@ -544,7 +537,8 @@ int devfreq_remove_device(struct devfreq *devfreq)
 	if (!devfreq)
 		return -EINVAL;
 
-	_remove_devfreq(devfreq, false);
+	device_unregister(&devfreq->dev);
+	put_device(&devfreq->dev);
 
 	return 0;
 }
-- 
cgit v1.2.3-70-g09d2


From 8cd84092d35e52372da2c3c3c2afb1a719917af2 Mon Sep 17 00:00:00 2001
From: Chanwoo Choi <cw00.choi@samsung.com>
Date: Fri, 9 May 2014 16:43:08 +0900
Subject: PM / devfreq: Add resource-managed function for devfreq device

This patch add resource-managed function for devfreq device as following
functions. The devm_devfreq_add_device() manages automatically the memory
of devfreq device using device resource management.
- devm_devfreq_add_device()
- devm_devfreq_remove_device()

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
---
 drivers/devfreq/devfreq.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/devfreq.h   | 21 +++++++++++++++-
 2 files changed, 83 insertions(+), 1 deletion(-)

(limited to 'drivers/devfreq/devfreq.c')

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index af4af770857..8b6295d9d1f 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -544,6 +544,69 @@ int devfreq_remove_device(struct devfreq *devfreq)
 }
 EXPORT_SYMBOL(devfreq_remove_device);
 
+static int devm_devfreq_dev_match(struct device *dev, void *res, void *data)
+{
+	struct devfreq **r = res;
+
+	if (WARN_ON(!r || !*r))
+		return 0;
+
+	return *r == data;
+}
+
+static void devm_devfreq_dev_release(struct device *dev, void *res)
+{
+	devfreq_remove_device(*(struct devfreq **)res);
+}
+
+/**
+ * devm_devfreq_add_device() - Resource-managed devfreq_add_device()
+ * @dev:	the device to add devfreq feature.
+ * @profile:	device-specific profile to run devfreq.
+ * @governor_name:	name of the policy to choose frequency.
+ * @data:	private data for the governor. The devfreq framework does not
+ *		touch this value.
+ *
+ * This function manages automatically the memory of devfreq device using device
+ * resource management and simplify the free operation for memory of devfreq
+ * device.
+ */
+struct devfreq *devm_devfreq_add_device(struct device *dev,
+					struct devfreq_dev_profile *profile,
+					const char *governor_name,
+					void *data)
+{
+	struct devfreq **ptr, *devfreq;
+
+	ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	devfreq = devfreq_add_device(dev, profile, governor_name, data);
+	if (IS_ERR(devfreq)) {
+		devres_free(ptr);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	*ptr = devfreq;
+	devres_add(dev, ptr);
+
+	return devfreq;
+}
+EXPORT_SYMBOL(devm_devfreq_add_device);
+
+/**
+ * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
+ * @dev:	the device to add devfreq feature.
+ * @devfreq:	the devfreq instance to be removed
+ */
+void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq)
+{
+	WARN_ON(devres_release(dev, devm_devfreq_dev_release,
+			       devm_devfreq_dev_match, devfreq));
+}
+EXPORT_SYMBOL(devm_devfreq_remove_device);
+
 /**
  * devfreq_suspend_device() - Suspend devfreq of a device.
  * @devfreq: the devfreq instance to be suspended
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index d48dc00232a..023d668a2cb 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -181,6 +181,12 @@ extern struct devfreq *devfreq_add_device(struct device *dev,
 				  const char *governor_name,
 				  void *data);
 extern int devfreq_remove_device(struct devfreq *devfreq);
+extern struct devfreq *devm_devfreq_add_device(struct device *dev,
+				  struct devfreq_dev_profile *profile,
+				  const char *governor_name,
+				  void *data);
+extern void devm_devfreq_remove_device(struct device *dev,
+				  struct devfreq *devfreq);
 
 /* Supposed to be called by PM_SLEEP/PM_RUNTIME callbacks */
 extern int devfreq_suspend_device(struct devfreq *devfreq);
@@ -220,7 +226,7 @@ static inline struct devfreq *devfreq_add_device(struct device *dev,
 					  const char *governor_name,
 					  void *data)
 {
-	return NULL;
+	return ERR_PTR(-ENOSYS);
 }
 
 static inline int devfreq_remove_device(struct devfreq *devfreq)
@@ -228,6 +234,19 @@ static inline int devfreq_remove_device(struct devfreq *devfreq)
 	return 0;
 }
 
+static inline struct devfreq *devm_devfreq_add_device(struct device *dev,
+					struct devfreq_dev_profile *profile,
+					const char *governor_name,
+					void *data)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
+static inline void devm_devfreq_remove_device(struct device *dev,
+					struct devfreq *devfreq)
+{
+}
+
 static inline int devfreq_suspend_device(struct devfreq *devfreq)
 {
 	return 0;
-- 
cgit v1.2.3-70-g09d2


From d5b040d0cab9cae1dc1ad61a07019062235f4878 Mon Sep 17 00:00:00 2001
From: Chanwoo Choi <cw00.choi@samsung.com>
Date: Fri, 9 May 2014 16:43:09 +0900
Subject: PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier
 function

This patch add resource-managed function for devfreq opp as following
functions. The devm_devfreq_register_opp_notifier() manages automatically
the registration of devfreq opp using device resource management.
- devm_devfreq_register_opp_notifier
- devm_devfreq_unregister_opp_notifier()

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
---
 drivers/devfreq/devfreq.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/devfreq.h   | 14 ++++++++++++++
 2 files changed, 62 insertions(+)

(limited to 'drivers/devfreq/devfreq.c')

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 8b6295d9d1f..9f90369dd6b 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -1169,6 +1169,54 @@ int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq)
 	return ret;
 }
 
+static void devm_devfreq_opp_release(struct device *dev, void *res)
+{
+	devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res);
+}
+
+/**
+ * devm_ devfreq_register_opp_notifier()
+ *		- Resource-managed devfreq_register_opp_notifier()
+ * @dev:	The devfreq user device. (parent of devfreq)
+ * @devfreq:	The devfreq object.
+ */
+int devm_devfreq_register_opp_notifier(struct device *dev,
+				       struct devfreq *devfreq)
+{
+	struct devfreq **ptr;
+	int ret;
+
+	ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = devfreq_register_opp_notifier(dev, devfreq);
+	if (ret) {
+		devres_free(ptr);
+		return ret;
+	}
+
+	*ptr = devfreq;
+	devres_add(dev, ptr);
+
+	return 0;
+}
+EXPORT_SYMBOL(devm_devfreq_register_opp_notifier);
+
+/**
+ * devm_devfreq_unregister_opp_notifier()
+ *		- Resource-managed devfreq_unregister_opp_notifier()
+ * @dev:	The devfreq user device. (parent of devfreq)
+ * @devfreq:	The devfreq object.
+ */
+void devm_devfreq_unregister_opp_notifier(struct device *dev,
+					 struct devfreq *devfreq)
+{
+	WARN_ON(devres_release(dev, devm_devfreq_opp_release,
+			       devm_devfreq_dev_match, devfreq));
+}
+EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier);
+
 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 MODULE_DESCRIPTION("devfreq class support");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 023d668a2cb..f1863dcd83e 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -199,6 +199,10 @@ extern int devfreq_register_opp_notifier(struct device *dev,
 					 struct devfreq *devfreq);
 extern int devfreq_unregister_opp_notifier(struct device *dev,
 					   struct devfreq *devfreq);
+extern int devm_devfreq_register_opp_notifier(struct device *dev,
+					      struct devfreq *devfreq);
+extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
+						struct devfreq *devfreq);
 
 #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
 /**
@@ -275,6 +279,16 @@ static inline int devfreq_unregister_opp_notifier(struct device *dev,
 	return -EINVAL;
 }
 
+static inline int devm_devfreq_register_opp_notifier(struct device *dev,
+						     struct devfreq *devfreq)
+{
+	return -EINVAL;
+}
+
+static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
+							struct devfreq *devfreq)
+{
+}
 #endif /* CONFIG_PM_DEVFREQ */
 
 #endif /* __LINUX_DEVFREQ_H__ */
-- 
cgit v1.2.3-70-g09d2