Commit 31f5396a authored by Jean Delvare's avatar Jean Delvare Committed by Len Brown
Browse files

thermal: make THERMAL_HWMON implementation fully internal 



THERMAL_HWMON is implemented inside the thermal_sys driver and has no
effect on drivers implementing thermal zones, so they shouldn't see
anything related to it in <linux/thermal.h>.  Making the THERMAL_HWMON
implementation fully internal has two advantages beyond the cleaner
design:

* This avoids rebuilding all thermal drivers if the THERMAL_HWMON
  implementation changes, or if CONFIG_THERMAL_HWMON gets enabled or
  disabled.

* This avoids breaking the thermal kABI in these cases too, which should
  make distributions happy.

The only drawback I can see is slightly higher memory fragmentation, as
the number of kzalloc() calls will increase by one per thermal zone.  But
I doubt it will be a problem in practice, as I've never seen a system with
more than two thermal zones.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Cc: Rene Herman <rene.herman@gmail.com>
Acked-by: default avatarGuenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 0d97d7a4

drivers/thermal/thermal_sys.c

+92 −25
Original line number Diff line number Diff line
@@ -420,6 +420,29 @@ thermal_cooling_device_trip_point_show(struct device *dev, 


/* hwmon sys I/F */

#include <linux/hwmon.h>



/* thermal zone devices with the same type share one hwmon device */

struct thermal_hwmon_device {

	char type[THERMAL_NAME_LENGTH];

	struct device *device;

	int count;

	struct list_head tz_list;

	struct list_head node;

};



struct thermal_hwmon_attr {

	struct device_attribute attr;

	char name[16];

};



/* one temperature input for each thermal zone */

struct thermal_hwmon_temp {

	struct list_head hwmon_node;

	struct thermal_zone_device *tz;

	struct thermal_hwmon_attr temp_input;	/* hwmon sys attr */

	struct thermal_hwmon_attr temp_crit;	/* hwmon sys attr */

};



static LIST_HEAD(thermal_hwmon_list);



static ssize_t
@@ -437,9 +460,10 @@ temp_input_show(struct device *dev, struct device_attribute *attr, char *buf) 
	int ret;

	struct thermal_hwmon_attr *hwmon_attr

			= container_of(attr, struct thermal_hwmon_attr, attr);

	struct thermal_zone_device *tz

			= container_of(hwmon_attr, struct thermal_zone_device,

	struct thermal_hwmon_temp *temp

			= container_of(hwmon_attr, struct thermal_hwmon_temp,

				       temp_input);

	struct thermal_zone_device *tz = temp->tz;



	ret = tz->ops->get_temp(tz, &temperature);
@@ -455,9 +479,10 @@ temp_crit_show(struct device *dev, struct device_attribute *attr, 
{

	struct thermal_hwmon_attr *hwmon_attr

			= container_of(attr, struct thermal_hwmon_attr, attr);

	struct thermal_zone_device *tz

			= container_of(hwmon_attr, struct thermal_zone_device,

	struct thermal_hwmon_temp *temp

			= container_of(hwmon_attr, struct thermal_hwmon_temp,

				       temp_crit);

	struct thermal_zone_device *tz = temp->tz;

	long temperature;

	int ret;
@@ -485,10 +510,29 @@ thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz) 
	return NULL;

}



/* Find the temperature input matching a given thermal zone */

static struct thermal_hwmon_temp *

thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,

			  const struct thermal_zone_device *tz)

{

	struct thermal_hwmon_temp *temp;



	mutex_lock(&thermal_list_lock);

	list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)

		if (temp->tz == tz) {

			mutex_unlock(&thermal_list_lock);

			return temp;

		}

	mutex_unlock(&thermal_list_lock);



	return NULL;

}



static int

thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)

{

	struct thermal_hwmon_device *hwmon;

	struct thermal_hwmon_temp *temp;

	int new_hwmon_device = 1;

	int result;
@@ -515,30 +559,36 @@ thermal_add_hwmon_sysfs(struct thermal_zone_device *tz) 
		goto free_mem;



 register_sys_interface:

	tz->hwmon = hwmon;

	temp = kzalloc(sizeof(struct thermal_hwmon_temp), GFP_KERNEL);

	if (!temp) {

		result = -ENOMEM;

		goto unregister_name;

	}



	temp->tz = tz;

	hwmon->count++;



	snprintf(tz->temp_input.name, THERMAL_NAME_LENGTH,

	snprintf(temp->temp_input.name, THERMAL_NAME_LENGTH,

		 "temp%d_input", hwmon->count);

	tz->temp_input.attr.attr.name = tz->temp_input.name;

	tz->temp_input.attr.attr.mode = 0444;

	tz->temp_input.attr.show = temp_input_show;

	sysfs_attr_init(&tz->temp_input.attr.attr);

	result = device_create_file(hwmon->device, &tz->temp_input.attr);

	temp->temp_input.attr.attr.name = temp->temp_input.name;

	temp->temp_input.attr.attr.mode = 0444;

	temp->temp_input.attr.show = temp_input_show;

	sysfs_attr_init(&temp->temp_input.attr.attr);

	result = device_create_file(hwmon->device, &temp->temp_input.attr);

	if (result)

		goto unregister_name;

		goto free_temp_mem;



	if (tz->ops->get_crit_temp) {

		unsigned long temperature;

		if (!tz->ops->get_crit_temp(tz, &temperature)) {

			snprintf(tz->temp_crit.name, THERMAL_NAME_LENGTH,

			snprintf(temp->temp_crit.name, THERMAL_NAME_LENGTH,

				"temp%d_crit", hwmon->count);

			tz->temp_crit.attr.attr.name = tz->temp_crit.name;

			tz->temp_crit.attr.attr.mode = 0444;

			tz->temp_crit.attr.show = temp_crit_show;

			sysfs_attr_init(&tz->temp_crit.attr.attr);

			temp->temp_crit.attr.attr.name = temp->temp_crit.name;

			temp->temp_crit.attr.attr.mode = 0444;

			temp->temp_crit.attr.show = temp_crit_show;

			sysfs_attr_init(&temp->temp_crit.attr.attr);

			result = device_create_file(hwmon->device,

						    &tz->temp_crit.attr);

						    &temp->temp_crit.attr);

			if (result)

				goto unregister_input;

		}
@@ -547,13 +597,15 @@ thermal_add_hwmon_sysfs(struct thermal_zone_device *tz) 
	mutex_lock(&thermal_list_lock);

	if (new_hwmon_device)

		list_add_tail(&hwmon->node, &thermal_hwmon_list);

	list_add_tail(&tz->hwmon_node, &hwmon->tz_list);

	list_add_tail(&temp->hwmon_node, &hwmon->tz_list);

	mutex_unlock(&thermal_list_lock);



	return 0;



 unregister_input:

	device_remove_file(hwmon->device, &tz->temp_input.attr);

	device_remove_file(hwmon->device, &temp->temp_input.attr);

 free_temp_mem:

	kfree(temp);

 unregister_name:

	if (new_hwmon_device) {

		device_remove_file(hwmon->device, &dev_attr_name);
@@ -569,15 +621,30 @@ thermal_add_hwmon_sysfs(struct thermal_zone_device *tz) 
static void

thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)

{

	struct thermal_hwmon_device *hwmon = tz->hwmon;

	struct thermal_hwmon_device *hwmon;

	struct thermal_hwmon_temp *temp;



	hwmon = thermal_hwmon_lookup_by_type(tz);

	if (unlikely(!hwmon)) {

		/* Should never happen... */

		dev_dbg(&tz->device, "hwmon device lookup failed!\n");

		return;

	}



	temp = thermal_hwmon_lookup_temp(hwmon, tz);

	if (unlikely(!temp)) {

		/* Should never happen... */

		dev_dbg(&tz->device, "temperature input lookup failed!\n");

		return;

	}



	tz->hwmon = NULL;

	device_remove_file(hwmon->device, &tz->temp_input.attr);

	device_remove_file(hwmon->device, &temp->temp_input.attr);

	if (tz->ops->get_crit_temp)

		device_remove_file(hwmon->device, &tz->temp_crit.attr);

		device_remove_file(hwmon->device, &temp->temp_crit.attr);



	mutex_lock(&thermal_list_lock);

	list_del(&tz->hwmon_node);

	list_del(&temp->hwmon_node);

	kfree(temp);

	if (!list_empty(&hwmon->tz_list)) {

		mutex_unlock(&thermal_list_lock);

		return;

include/linux/thermal.h

+0 −22
Original line number Diff line number Diff line
@@ -85,22 +85,6 @@ struct thermal_cooling_device { 
				((long)t-2732+5)/10 : ((long)t-2732-5)/10)

#define CELSIUS_TO_KELVIN(t)	((t)*10+2732)



#if defined(CONFIG_THERMAL_HWMON)

/* thermal zone devices with the same type share one hwmon device */

struct thermal_hwmon_device {

	char type[THERMAL_NAME_LENGTH];

	struct device *device;

	int count;

	struct list_head tz_list;

	struct list_head node;

};



struct thermal_hwmon_attr {

	struct device_attribute attr;

	char name[16];

};

#endif



struct thermal_zone_device {

	int id;

	char type[THERMAL_NAME_LENGTH];
@@ -120,12 +104,6 @@ struct thermal_zone_device { 
	struct mutex lock;	/* protect cooling devices list */

	struct list_head node;

	struct delayed_work poll_queue;

#if defined(CONFIG_THERMAL_HWMON)

	struct list_head hwmon_node;

	struct thermal_hwmon_device *hwmon;

	struct thermal_hwmon_attr temp_input;	/* hwmon sys attr */

	struct thermal_hwmon_attr temp_crit;	/* hwmon sys attr */

#endif

};

/* Adding event notification support elements */

#define THERMAL_GENL_FAMILY_NAME                "thermal_event"

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