Re: [PATCH 1/6] thermal: Introduce devm_thermal_of_cooling_device_register

From: Guenter Roeck
Date: Sat May 11 2019 - 16:24:16 EST


Hi Eduardo,

On 5/11/19 12:04 PM, Eduardo Valentin wrote:
Hello Guenter,

On Thu, Apr 18, 2019 at 12:58:15PM -0700, Guenter Roeck wrote:
thermal_of_cooling_device_register() and thermal_cooling_device_register()
are typically called from driver probe functions, and
thermal_cooling_device_unregister() is called from remove functions. This
makes both a perfect candidate for device managed functions.

Introduce devm_thermal_of_cooling_device_register(). This function can
also be used to replace thermal_cooling_device_register() by passing a NULL
pointer as device node. The new function requires both struct device *
and struct device_node * as parameters since the struct device_node *
parameter is not always identical to dev->of_node.

Don't introduce a device managed remove function since it is not needed
at this point.

I don't have any objection on adding this API. Only a minor thing below:



Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/thermal/thermal_core.c | 49 ++++++++++++++++++++++++++++++++++++++++++
include/linux/thermal.h | 5 +++++
2 files changed, 54 insertions(+)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 6590bb5cb688..e0b530603db6 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1046,6 +1046,55 @@ thermal_of_cooling_device_register(struct device_node *np,
}
EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
+static void thermal_cooling_device_release(struct device *dev, void *res)
+{
+ thermal_cooling_device_unregister(
+ *(struct thermal_cooling_device **)res);
+}
+
+/**
+ * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
+ * device
+ * @dev: a valid struct device pointer of a sensor device.
+ * @np: a pointer to a device tree node.
+ * @type: the thermal cooling device type.
+ * @devdata: device private data.
+ * @ops: standard thermal cooling devices callbacks.
+ *
+ * This function will register a cooling device with device tree node reference.
+ * This interface function adds a new thermal cooling device (fan/processor/...)
+ * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
+ * to all the thermal zone devices registered at the same time.
+ *
+ * Return: a pointer to the created struct thermal_cooling_device or an
+ * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
+ */
+struct thermal_cooling_device *
+devm_thermal_of_cooling_device_register(struct device *dev,
+ struct device_node *np,
+ char *type, void *devdata,
+ const struct thermal_cooling_device_ops *ops)
+{
+ struct thermal_cooling_device **ptr, *tcd;
+
+ ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ tcd = __thermal_cooling_device_register(np, type, devdata, ops);
+ if (IS_ERR(tcd)) {
+ devres_free(ptr);
+ return tcd;
+ }
+
+ *ptr = tcd;
+ devres_add(dev, ptr);
+
+ return tcd;
+}
+EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
+
static void __unbind(struct thermal_zone_device *tz, int mask,
struct thermal_cooling_device *cdev)
{
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 5f4705f46c2f..43cf4fdd71d4 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -447,6 +447,11 @@ struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
struct thermal_cooling_device *
thermal_of_cooling_device_register(struct device_node *np, 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,
+ const struct thermal_cooling_device_ops *ops);

We need to stub this in case thermal is not selected.


Yes. Sorry, that completely slipped my mind.

void thermal_cooling_device_unregister(struct thermal_cooling_device *);
struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);

Something like:


diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 43cf4fd..9b1b365 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -508,6 +508,14 @@ 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); }
+struct thermal_cooling_device *
+devm_thermal_of_cooling_device_register(struct device *dev,
+ struct device_node *np,
+ char *type, void *devdata,
+ const struct thermal_cooling_device_ops *ops)
+{
+ return ERR_PTR(-ENODEV);
+}
static inline void thermal_cooling_device_unregister(
struct thermal_cooling_device *cdev)
{ }
~


If you want I can amend this to your patch and apply it.

Please do.

Also, do you prefer me to collect only this patch and you would collect hwmon changes,
or are you ok if I collect all the series?


Please go ahead and collect the entire series.

Thanks,
Guenter