[linux-2.6-block.git] / drivers / thermal / thermal_hwmon.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  thermal_hwmon.c - Generic Thermal Management hwmon support.
 *
 *  Code based on Intel thermal_core.c. Copyrights of the original code:
 *  Copyright (C) 2008 Intel Corp
 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
 *
 *  Copyright (C) 2013 Texas Instruments
 *  Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
 */
#include <linux/hwmon.h>
#include <linux/thermal.h>
#include <linux/slab.h>
#include <linux/err.h>
#include "thermal_hwmon.h"

/* hwmon sys I/F */
/* 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 DEFINE_MUTEX(thermal_hwmon_list_lock);

static ssize_t
temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	int temperature;
	int ret;
	struct thermal_hwmon_attr *hwmon_attr
			= container_of(attr, struct thermal_hwmon_attr, attr);
	struct thermal_hwmon_temp *temp
			= container_of(hwmon_attr, struct thermal_hwmon_temp,
				       temp_input);
	struct thermal_zone_device *tz = temp->tz;

	ret = thermal_zone_get_temp(tz, &temperature);

	if (ret)
		return ret;

	return sprintf(buf, "%d\n", temperature);
}

static ssize_t
temp_crit_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct thermal_hwmon_attr *hwmon_attr
			= container_of(attr, struct thermal_hwmon_attr, attr);
	struct thermal_hwmon_temp *temp
			= container_of(hwmon_attr, struct thermal_hwmon_temp,
				       temp_crit);
	struct thermal_zone_device *tz = temp->tz;
	int temperature;
	int ret;

	ret = tz->ops->get_crit_temp(tz, &temperature);
	if (ret)
		return ret;

	return sprintf(buf, "%d\n", temperature);
}


static struct thermal_hwmon_device *
thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
{
	struct thermal_hwmon_device *hwmon;

	mutex_lock(&thermal_hwmon_list_lock);
	list_for_each_entry(hwmon, &thermal_hwmon_list, node)
		if (!strcmp(hwmon->type, tz->type)) {
			mutex_unlock(&thermal_hwmon_list_lock);
			return hwmon;
		}
	mutex_unlock(&thermal_hwmon_list_lock);

	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_hwmon_list_lock);
	list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)
		if (temp->tz == tz) {
			mutex_unlock(&thermal_hwmon_list_lock);
			return temp;
		}
	mutex_unlock(&thermal_hwmon_list_lock);

	return NULL;
}

static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
{
	int temp;
	return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
}

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;

	hwmon = thermal_hwmon_lookup_by_type(tz);
	if (hwmon) {
		new_hwmon_device = 0;
		goto register_sys_interface;
	}

	hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
	if (!hwmon)
		return -ENOMEM;

	INIT_LIST_HEAD(&hwmon->tz_list);
	strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
	hwmon->device = hwmon_device_register_with_info(NULL, hwmon->type,
							hwmon, NULL, NULL);
	if (IS_ERR(hwmon->device)) {
		result = PTR_ERR(hwmon->device);
		goto free_mem;
	}

 register_sys_interface:
	temp = kzalloc(sizeof(*temp), GFP_KERNEL);
	if (!temp) {
		result = -ENOMEM;
		goto unregister_name;
	}

	temp->tz = tz;
	hwmon->count++;

	snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
		 "temp%d_input", hwmon->count);
	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 free_temp_mem;

	if (thermal_zone_crit_temp_valid(tz)) {
		snprintf(temp->temp_crit.name,
				sizeof(temp->temp_crit.name),
				"temp%d_crit", hwmon->count);
		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,
					    &temp->temp_crit.attr);
		if (result)
			goto unregister_input;
	}

	mutex_lock(&thermal_hwmon_list_lock);
	if (new_hwmon_device)
		list_add_tail(&hwmon->node, &thermal_hwmon_list);
	list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
	mutex_unlock(&thermal_hwmon_list_lock);

	return 0;

 unregister_input:
	device_remove_file(hwmon->device, &temp->temp_input.attr);
 free_temp_mem:
	kfree(temp);
 unregister_name:
	if (new_hwmon_device)
		hwmon_device_unregister(hwmon->device);
 free_mem:
	if (new_hwmon_device)
		kfree(hwmon);

	return result;
}
EXPORT_SYMBOL_GPL(thermal_add_hwmon_sysfs);

void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
{
	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;
	}

	device_remove_file(hwmon->device, &temp->temp_input.attr);
	if (thermal_zone_crit_temp_valid(tz))
		device_remove_file(hwmon->device, &temp->temp_crit.attr);

	mutex_lock(&thermal_hwmon_list_lock);
	list_del(&temp->hwmon_node);
	kfree(temp);
	if (!list_empty(&hwmon->tz_list)) {
		mutex_unlock(&thermal_hwmon_list_lock);
		return;
	}
	list_del(&hwmon->node);
	mutex_unlock(&thermal_hwmon_list_lock);

	hwmon_device_unregister(hwmon->device);
	kfree(hwmon);
}
EXPORT_SYMBOL_GPL(thermal_remove_hwmon_sysfs);
Commit	Line	Data
7e3c0381	1	// SPDX-License-Identifier: GPL-2.0
0dd88793 EV	2	/*
	3	* thermal_hwmon.c - Generic Thermal Management hwmon support.
	4	*
	5	* Code based on Intel thermal_core.c. Copyrights of the original code:
	6	* Copyright (C) 2008 Intel Corp
	7	* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
	8	* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
	9	*
	10	* Copyright (C) 2013 Texas Instruments
	11	* Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
0dd88793 EV	12	*/
	13	#include <linux/hwmon.h>
	14	#include <linux/thermal.h>
	15	#include <linux/slab.h>
	16	#include <linux/err.h>
	17	#include "thermal_hwmon.h"
	18
	19	/* hwmon sys I/F */
	20	/* thermal zone devices with the same type share one hwmon device */
	21	struct thermal_hwmon_device {
	22	char type[THERMAL_NAME_LENGTH];
	23	struct device *device;
	24	int count;
	25	struct list_head tz_list;
	26	struct list_head node;
	27	};
	28
	29	struct thermal_hwmon_attr {
	30	struct device_attribute attr;
	31	char name[16];
	32	};
	33
	34	/* one temperature input for each thermal zone */
	35	struct thermal_hwmon_temp {
	36	struct list_head hwmon_node;
	37	struct thermal_zone_device *tz;
	38	struct thermal_hwmon_attr temp_input; /* hwmon sys attr */
	39	struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */
	40	};
	41
	42	static LIST_HEAD(thermal_hwmon_list);
	43
	44	static DEFINE_MUTEX(thermal_hwmon_list_lock);
	45
0dd88793 EV	46	static ssize_t
	47	temp_input_show(struct device dev, struct device_attribute attr, char *buf)
	48	{
17e8351a	49	int temperature;
0dd88793 EV	50	int ret;
	51	struct thermal_hwmon_attr *hwmon_attr
	52	= container_of(attr, struct thermal_hwmon_attr, attr);
	53	struct thermal_hwmon_temp *temp
	54	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	55	temp_input);
	56	struct thermal_zone_device *tz = temp->tz;
	57
	58	ret = thermal_zone_get_temp(tz, &temperature);
	59
	60	if (ret)
	61	return ret;
	62
17e8351a	63	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	64	}
	65
	66	static ssize_t
	67	temp_crit_show(struct device dev, struct device_attribute attr, char *buf)
	68	{
	69	struct thermal_hwmon_attr *hwmon_attr
	70	= container_of(attr, struct thermal_hwmon_attr, attr);
	71	struct thermal_hwmon_temp *temp
	72	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	73	temp_crit);
	74	struct thermal_zone_device *tz = temp->tz;
17e8351a	75	int temperature;
0dd88793 EV	76	int ret;
0dd88793 EV	77
f37fabb8	78	ret = tz->ops->get_crit_temp(tz, &temperature);
0dd88793 EV	79	if (ret)
	80	return ret;
	81
17e8351a	82	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	83	}
	84
	85
	86	static struct thermal_hwmon_device *
	87	thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
	88	{
	89	struct thermal_hwmon_device *hwmon;
	90
	91	mutex_lock(&thermal_hwmon_list_lock);
	92	list_for_each_entry(hwmon, &thermal_hwmon_list, node)
	93	if (!strcmp(hwmon->type, tz->type)) {
	94	mutex_unlock(&thermal_hwmon_list_lock);
	95	return hwmon;
	96	}
	97	mutex_unlock(&thermal_hwmon_list_lock);
	98
	99	return NULL;
	100	}
	101
	102	/* Find the temperature input matching a given thermal zone */
	103	static struct thermal_hwmon_temp *
	104	thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,
	105	const struct thermal_zone_device *tz)
	106	{
	107	struct thermal_hwmon_temp *temp;
	108
	109	mutex_lock(&thermal_hwmon_list_lock);
	110	list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)
	111	if (temp->tz == tz) {
	112	mutex_unlock(&thermal_hwmon_list_lock);
	113	return temp;
	114	}
	115	mutex_unlock(&thermal_hwmon_list_lock);
	116
	117	return NULL;
	118	}
	119
e8db5d67 AL	120	static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
e8db5d67 AL	121	{
17e8351a	122	int temp;
e8db5d67 AL	123	return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
	124	}
	125
0dd88793 EV	126	int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
	127	{
	128	struct thermal_hwmon_device *hwmon;
	129	struct thermal_hwmon_temp *temp;
	130	int new_hwmon_device = 1;
	131	int result;
	132
	133	hwmon = thermal_hwmon_lookup_by_type(tz);
	134	if (hwmon) {
	135	new_hwmon_device = 0;
	136	goto register_sys_interface;
	137	}
	138
	139	hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
	140	if (!hwmon)
	141	return -ENOMEM;
	142
	143	INIT_LIST_HEAD(&hwmon->tz_list);
	144	strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
e782bc16 FE	145	hwmon->device = hwmon_device_register_with_info(NULL, hwmon->type,
e782bc16 FE	146	hwmon, NULL, NULL);
0dd88793 EV	147	if (IS_ERR(hwmon->device)) {
	148	result = PTR_ERR(hwmon->device);
	149	goto free_mem;
	150	}
0dd88793 EV	151
	152	register_sys_interface:
	153	temp = kzalloc(sizeof(*temp), GFP_KERNEL);
	154	if (!temp) {
	155	result = -ENOMEM;
	156	goto unregister_name;
	157	}
	158
	159	temp->tz = tz;
	160	hwmon->count++;
	161
	162	snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
	163	"temp%d_input", hwmon->count);
	164	temp->temp_input.attr.attr.name = temp->temp_input.name;
	165	temp->temp_input.attr.attr.mode = 0444;
	166	temp->temp_input.attr.show = temp_input_show;
	167	sysfs_attr_init(&temp->temp_input.attr.attr);
	168	result = device_create_file(hwmon->device, &temp->temp_input.attr);
	169	if (result)
	170	goto free_temp_mem;
	171
e8db5d67 AL	172	if (thermal_zone_crit_temp_valid(tz)) {
	173	snprintf(temp->temp_crit.name,
	174	sizeof(temp->temp_crit.name),
0dd88793	175	"temp%d_crit", hwmon->count);
e8db5d67 AL	176	temp->temp_crit.attr.attr.name = temp->temp_crit.name;
	177	temp->temp_crit.attr.attr.mode = 0444;
	178	temp->temp_crit.attr.show = temp_crit_show;
	179	sysfs_attr_init(&temp->temp_crit.attr.attr);
	180	result = device_create_file(hwmon->device,
	181	&temp->temp_crit.attr);
	182	if (result)
	183	goto unregister_input;
0dd88793 EV	184	}
	185
	186	mutex_lock(&thermal_hwmon_list_lock);
	187	if (new_hwmon_device)
	188	list_add_tail(&hwmon->node, &thermal_hwmon_list);
	189	list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
	190	mutex_unlock(&thermal_hwmon_list_lock);
	191
	192	return 0;
	193
	194	unregister_input:
	195	device_remove_file(hwmon->device, &temp->temp_input.attr);
	196	free_temp_mem:
	197	kfree(temp);
	198	unregister_name:
e782bc16	199	if (new_hwmon_device)
0dd88793	200	hwmon_device_unregister(hwmon->device);
0dd88793 EV	201	free_mem:
	202	if (new_hwmon_device)
	203	kfree(hwmon);
	204
	205	return result;
	206	}
f4c59243	207	EXPORT_SYMBOL_GPL(thermal_add_hwmon_sysfs);
0dd88793 EV	208
	209	void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
	210	{
	211	struct thermal_hwmon_device *hwmon;
	212	struct thermal_hwmon_temp *temp;
	213
	214	hwmon = thermal_hwmon_lookup_by_type(tz);
	215	if (unlikely(!hwmon)) {
	216	/* Should never happen... */
	217	dev_dbg(&tz->device, "hwmon device lookup failed!\n");
	218	return;
	219	}
	220
	221	temp = thermal_hwmon_lookup_temp(hwmon, tz);
	222	if (unlikely(!temp)) {
	223	/* Should never happen... */
	224	dev_dbg(&tz->device, "temperature input lookup failed!\n");
	225	return;
	226	}
	227
	228	device_remove_file(hwmon->device, &temp->temp_input.attr);
e8db5d67	229	if (thermal_zone_crit_temp_valid(tz))
0dd88793 EV	230	device_remove_file(hwmon->device, &temp->temp_crit.attr);
	231
	232	mutex_lock(&thermal_hwmon_list_lock);
	233	list_del(&temp->hwmon_node);
	234	kfree(temp);
	235	if (!list_empty(&hwmon->tz_list)) {
	236	mutex_unlock(&thermal_hwmon_list_lock);
	237	return;
	238	}
	239	list_del(&hwmon->node);
	240	mutex_unlock(&thermal_hwmon_list_lock);
	241
0dd88793 EV	242	hwmon_device_unregister(hwmon->device);
	243	kfree(hwmon);
	244	}
f4c59243	245	EXPORT_SYMBOL_GPL(thermal_remove_hwmon_sysfs);