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>

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index af4af77..8b6295d 100644 (file)
--- 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 d48dc00..023d668 100644 (file)
--- 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;