[Patch v4 3/7] thermal: core: Allow cooling devices to register a parent.

[Thara Gopinath <thara.gopinath@xxxxxxxxxx>]

With introduction of power domain warming devices, devices that control the
power domain are registered as the parent of the cooling device so that the
device-genpd hierarchy in kernel is maintained intact. To enable this,
introduce a new API thermal_of_cooling_device_parent_register that takes a
parent device pointer as input. Also, modify
__thermal_cooling_device_register to register parent of a newly created
cooling device, if specified.

Signed-off-by: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
---
 drivers/thermal/thermal_core.c | 22 +++++++++++++++++++---
 include/linux/thermal.h        | 15 +++++++++++++++
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index d4481cc..912ba75 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -947,6 +947,7 @@ static void bind_cdev(struct thermal_cooling_device *cdev)
  */
 static struct thermal_cooling_device *
 __thermal_cooling_device_register(struct device_node *np,
+				  struct device *parent,
 				  const char *type, void *devdata,
 				  const struct thermal_cooling_device_ops *ops)
 {
@@ -979,6 +980,8 @@ __thermal_cooling_device_register(struct device_node *np,
 	cdev->ops = ops;
 	cdev->updated = false;
 	cdev->device.class = &thermal_class;
+	if (parent)
+		cdev->device.parent = parent;
 	cdev->devdata = devdata;
 	thermal_cooling_device_setup_sysfs(cdev);
 	dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
@@ -1024,7 +1027,8 @@ struct thermal_cooling_device *
 thermal_cooling_device_register(const char *type, void *devdata,
 				const struct thermal_cooling_device_ops *ops)
 {
-	return __thermal_cooling_device_register(NULL, type, devdata, ops);
+	return __thermal_cooling_device_register(NULL, NULL, type,
+						 devdata, ops);
 }
 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 
@@ -1048,10 +1052,22 @@ thermal_of_cooling_device_register(struct device_node *np,
 				   const char *type, void *devdata,
 				   const struct thermal_cooling_device_ops *ops)
 {
-	return __thermal_cooling_device_register(np, type, devdata, ops);
+	return __thermal_cooling_device_register(np, NULL, type, devdata, ops);
 }
 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
 
+struct thermal_cooling_device *
+thermal_of_cooling_device_parent_register(struct device_node *np,
+					  struct device *parent,
+					  const char *type, void *devdata,
+					  const struct
+					  thermal_cooling_device_ops *ops)
+{
+	return __thermal_cooling_device_register(np, parent, type,
+						 devdata, ops);
+}
+EXPORT_SYMBOL_GPL(thermal_of_cooling_device_parent_register);
+
 static void thermal_cooling_device_release(struct device *dev, void *res)
 {
 	thermal_cooling_device_unregister(
@@ -1088,7 +1104,7 @@ devm_thermal_of_cooling_device_register(struct device *dev,
 	if (!ptr)
 		return ERR_PTR(-ENOMEM);
 
-	tcd = __thermal_cooling_device_register(np, type, devdata, ops);
+	tcd = __thermal_cooling_device_register(np, NULL, type, devdata, ops);
 	if (IS_ERR(tcd)) {
 		devres_free(ptr);
 		return tcd;
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index e45659c..ac5f268 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -448,6 +448,11 @@ struct thermal_cooling_device *
 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
 				   const struct thermal_cooling_device_ops *);
 struct thermal_cooling_device *
+thermal_of_cooling_device_parent_register(struct device_node *np,
+					  struct device *parent,
+					  const char *, void *, const struct
+					  thermal_cooling_device_ops *);
+struct thermal_cooling_device *
 devm_thermal_of_cooling_device_register(struct device *dev,
 				struct device_node *np,
 				char *type, void *devdata,
@@ -508,6 +513,16 @@ static inline struct thermal_cooling_device *
 thermal_of_cooling_device_register(struct device_node *np,
 	char *type, void *devdata, const struct thermal_cooling_device_ops *ops)
 { return ERR_PTR(-ENODEV); }
+
+static inline struct thermal_cooling_device *
+thermal_of_cooling_device_parent_register(struct device_node *np,
+					  struct device *parent,
+					  const char *, void *, const struct
+					  thermal_cooling_device_ops *)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline struct thermal_cooling_device *
 devm_thermal_of_cooling_device_register(struct device *dev,
 				struct device_node *np,
-- 
2.1.4