[linux-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/err.h>
#include <linux/export.h>
#include <linux/hwmon.h>
#include <linux/slab.h>
#include <linux/thermal.h>

#include "thermal_hwmon.h"
#include "thermal_core.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;

	mutex_lock(&tz->lock);

	if (device_is_registered(&tz->device))
		ret = tz->ops->get_crit_temp(tz, &temperature);
	else
		ret = -ENODEV;

	mutex_unlock(&tz->lock);

	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;
	char type[THERMAL_NAME_LENGTH];

	mutex_lock(&thermal_hwmon_list_lock);
	list_for_each_entry(hwmon, &thermal_hwmon_list, node) {
		strcpy(type, tz->type);
		strreplace(type, '-', '_');
		if (!strcmp(hwmon->type, 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);
	strscpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
	strreplace(hwmon->type, '-', '_');
	hwmon->device = hwmon_device_register_for_thermal(&tz->device,
							  hwmon->type, hwmon);
	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:
	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);

static void devm_thermal_hwmon_release(struct device *dev, void *res)
{
	thermal_remove_hwmon_sysfs(*(struct thermal_zone_device **)res);
}

int devm_thermal_add_hwmon_sysfs(struct device *dev, struct thermal_zone_device *tz)
{
	struct thermal_zone_device **ptr;
	int ret;

	ptr = devres_alloc(devm_thermal_hwmon_release, sizeof(*ptr),
			   GFP_KERNEL);
	if (!ptr) {
		dev_warn(dev, "Failed to allocate device resource data\n");
		return -ENOMEM;
	}

	ret = thermal_add_hwmon_sysfs(tz);
	if (ret) {
		dev_warn(dev, "Failed to add hwmon sysfs attributes\n");
		devres_free(ptr);
		return ret;
	}

	*ptr = tz;
	devres_add(dev, ptr);

	return ret;
}
EXPORT_SYMBOL_GPL(devm_thermal_add_hwmon_sysfs);

MODULE_IMPORT_NS(HWMON_THERMAL);
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	12	*/
1330e04f	13	#include <linux/err.h>
e5ebf357	14	#include <linux/export.h>
0dd88793	15	#include <linux/hwmon.h>
0dd88793	16	#include <linux/slab.h>
1330e04f AK	17	#include <linux/thermal.h>
1330e04f AK	18
0dd88793	19	#include "thermal_hwmon.h"
ec2c8aae	20	#include "thermal_core.h"
0dd88793 EV	21
	22	/* hwmon sys I/F */
	23	/* thermal zone devices with the same type share one hwmon device */
	24	struct thermal_hwmon_device {
	25	char type[THERMAL_NAME_LENGTH];
	26	struct device *device;
	27	int count;
	28	struct list_head tz_list;
	29	struct list_head node;
	30	};
	31
	32	struct thermal_hwmon_attr {
	33	struct device_attribute attr;
	34	char name[16];
	35	};
	36
	37	/* one temperature input for each thermal zone */
	38	struct thermal_hwmon_temp {
	39	struct list_head hwmon_node;
	40	struct thermal_zone_device *tz;
	41	struct thermal_hwmon_attr temp_input; /* hwmon sys attr */
	42	struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */
	43	};
	44
	45	static LIST_HEAD(thermal_hwmon_list);
	46
	47	static DEFINE_MUTEX(thermal_hwmon_list_lock);
	48
0dd88793 EV	49	static ssize_t
	50	temp_input_show(struct device dev, struct device_attribute attr, char *buf)
	51	{
17e8351a	52	int temperature;
0dd88793 EV	53	int ret;
	54	struct thermal_hwmon_attr *hwmon_attr
	55	= container_of(attr, struct thermal_hwmon_attr, attr);
	56	struct thermal_hwmon_temp *temp
	57	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	58	temp_input);
	59	struct thermal_zone_device *tz = temp->tz;
	60
	61	ret = thermal_zone_get_temp(tz, &temperature);
	62
	63	if (ret)
	64	return ret;
	65
17e8351a	66	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	67	}
	68
	69	static ssize_t
	70	temp_crit_show(struct device dev, struct device_attribute attr, char *buf)
	71	{
	72	struct thermal_hwmon_attr *hwmon_attr
	73	= container_of(attr, struct thermal_hwmon_attr, attr);
	74	struct thermal_hwmon_temp *temp
	75	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	76	temp_crit);
	77	struct thermal_zone_device *tz = temp->tz;
17e8351a	78	int temperature;
0dd88793 EV	79	int ret;
0dd88793 EV	80
ea37bec5 GR	81	mutex_lock(&tz->lock);
	82
	83	if (device_is_registered(&tz->device))
	84	ret = tz->ops->get_crit_temp(tz, &temperature);
	85	else
	86	ret = -ENODEV;
	87
	88	mutex_unlock(&tz->lock);
	89
0dd88793 EV	90	if (ret)
	91	return ret;
	92
17e8351a	93	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	94	}
	95
	96
	97	static struct thermal_hwmon_device *
	98	thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
	99	{
	100	struct thermal_hwmon_device *hwmon;
8c7aa184	101	char type[THERMAL_NAME_LENGTH];
0dd88793 EV	102
0dd88793 EV	103	mutex_lock(&thermal_hwmon_list_lock);
8c7aa184 SM	104	list_for_each_entry(hwmon, &thermal_hwmon_list, node) {
	105	strcpy(type, tz->type);
	106	strreplace(type, '-', '_');
	107	if (!strcmp(hwmon->type, type)) {
0dd88793 EV	108	mutex_unlock(&thermal_hwmon_list_lock);
	109	return hwmon;
	110	}
8c7aa184	111	}
0dd88793 EV	112	mutex_unlock(&thermal_hwmon_list_lock);
	113
	114	return NULL;
	115	}
	116
	117	/* Find the temperature input matching a given thermal zone */
	118	static struct thermal_hwmon_temp *
	119	thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,
	120	const struct thermal_zone_device *tz)
	121	{
	122	struct thermal_hwmon_temp *temp;
	123
	124	mutex_lock(&thermal_hwmon_list_lock);
	125	list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)
	126	if (temp->tz == tz) {
	127	mutex_unlock(&thermal_hwmon_list_lock);
	128	return temp;
	129	}
	130	mutex_unlock(&thermal_hwmon_list_lock);
	131
	132	return NULL;
	133	}
	134
e8db5d67 AL	135	static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
e8db5d67 AL	136	{
17e8351a	137	int temp;
e8db5d67 AL	138	return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
	139	}
	140
0dd88793 EV	141	int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
	142	{
	143	struct thermal_hwmon_device *hwmon;
	144	struct thermal_hwmon_temp *temp;
	145	int new_hwmon_device = 1;
	146	int result;
	147
	148	hwmon = thermal_hwmon_lookup_by_type(tz);
	149	if (hwmon) {
	150	new_hwmon_device = 0;
	151	goto register_sys_interface;
	152	}
	153
	154	hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
	155	if (!hwmon)
	156	return -ENOMEM;
	157
	158	INIT_LIST_HEAD(&hwmon->tz_list);
1e6c8fb8	159	strscpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
409ef0ba	160	strreplace(hwmon->type, '-', '_');
87743bcf GR	161	hwmon->device = hwmon_device_register_for_thermal(&tz->device,
87743bcf GR	162	hwmon->type, hwmon);
0dd88793 EV	163	if (IS_ERR(hwmon->device)) {
	164	result = PTR_ERR(hwmon->device);
	165	goto free_mem;
	166	}
0dd88793 EV	167
	168	register_sys_interface:
	169	temp = kzalloc(sizeof(*temp), GFP_KERNEL);
	170	if (!temp) {
	171	result = -ENOMEM;
	172	goto unregister_name;
	173	}
	174
	175	temp->tz = tz;
	176	hwmon->count++;
	177
	178	snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
	179	"temp%d_input", hwmon->count);
	180	temp->temp_input.attr.attr.name = temp->temp_input.name;
	181	temp->temp_input.attr.attr.mode = 0444;
	182	temp->temp_input.attr.show = temp_input_show;
	183	sysfs_attr_init(&temp->temp_input.attr.attr);
	184	result = device_create_file(hwmon->device, &temp->temp_input.attr);
	185	if (result)
	186	goto free_temp_mem;
	187
e8db5d67 AL	188	if (thermal_zone_crit_temp_valid(tz)) {
	189	snprintf(temp->temp_crit.name,
	190	sizeof(temp->temp_crit.name),
0dd88793	191	"temp%d_crit", hwmon->count);
e8db5d67 AL	192	temp->temp_crit.attr.attr.name = temp->temp_crit.name;
	193	temp->temp_crit.attr.attr.mode = 0444;
	194	temp->temp_crit.attr.show = temp_crit_show;
	195	sysfs_attr_init(&temp->temp_crit.attr.attr);
	196	result = device_create_file(hwmon->device,
	197	&temp->temp_crit.attr);
	198	if (result)
	199	goto unregister_input;
0dd88793 EV	200	}
	201
	202	mutex_lock(&thermal_hwmon_list_lock);
	203	if (new_hwmon_device)
	204	list_add_tail(&hwmon->node, &thermal_hwmon_list);
	205	list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
	206	mutex_unlock(&thermal_hwmon_list_lock);
	207
	208	return 0;
	209
	210	unregister_input:
	211	device_remove_file(hwmon->device, &temp->temp_input.attr);
	212	free_temp_mem:
	213	kfree(temp);
	214	unregister_name:
e782bc16	215	if (new_hwmon_device)
0dd88793	216	hwmon_device_unregister(hwmon->device);
0dd88793	217	free_mem:
030a48b0	218	kfree(hwmon);
0dd88793 EV	219
	220	return result;
	221	}
f4c59243	222	EXPORT_SYMBOL_GPL(thermal_add_hwmon_sysfs);
0dd88793 EV	223
	224	void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
	225	{
	226	struct thermal_hwmon_device *hwmon;
	227	struct thermal_hwmon_temp *temp;
	228
	229	hwmon = thermal_hwmon_lookup_by_type(tz);
	230	if (unlikely(!hwmon)) {
	231	/* Should never happen... */
4eb7c2f3	232	dev_dbg(&tz->device, "hwmon device lookup failed!\n");
0dd88793 EV	233	return;
	234	}
	235
	236	temp = thermal_hwmon_lookup_temp(hwmon, tz);
	237	if (unlikely(!temp)) {
	238	/* Should never happen... */
d9dc0600	239	dev_dbg(&tz->device, "temperature input lookup failed!\n");
0dd88793 EV	240	return;
	241	}
	242
	243	device_remove_file(hwmon->device, &temp->temp_input.attr);
e8db5d67	244	if (thermal_zone_crit_temp_valid(tz))
0dd88793 EV	245	device_remove_file(hwmon->device, &temp->temp_crit.attr);
	246
	247	mutex_lock(&thermal_hwmon_list_lock);
	248	list_del(&temp->hwmon_node);
	249	kfree(temp);
	250	if (!list_empty(&hwmon->tz_list)) {
	251	mutex_unlock(&thermal_hwmon_list_lock);
	252	return;
	253	}
	254	list_del(&hwmon->node);
	255	mutex_unlock(&thermal_hwmon_list_lock);
	256
0dd88793 EV	257	hwmon_device_unregister(hwmon->device);
	258	kfree(hwmon);
	259	}
f4c59243	260	EXPORT_SYMBOL_GPL(thermal_remove_hwmon_sysfs);
c7fc403e AS	261
	262	static void devm_thermal_hwmon_release(struct device dev, void res)
	263	{
	264	thermal_remove_hwmon_sysfs((struct thermal_zone_device *)res);
	265	}
	266
4a16c190	267	int devm_thermal_add_hwmon_sysfs(struct device dev, struct thermal_zone_device tz)
c7fc403e AS	268	{
	269	struct thermal_zone_device **ptr;
	270	int ret;
	271
	272	ptr = devres_alloc(devm_thermal_hwmon_release, sizeof(*ptr),
	273	GFP_KERNEL);
8416ecfb YL	274	if (!ptr) {
8416ecfb YL	275	dev_warn(dev, "Failed to allocate device resource data\n");
c7fc403e	276	return -ENOMEM;
8416ecfb	277	}
c7fc403e AS	278
	279	ret = thermal_add_hwmon_sysfs(tz);
	280	if (ret) {
8416ecfb	281	dev_warn(dev, "Failed to add hwmon sysfs attributes\n");
c7fc403e AS	282	devres_free(ptr);
	283	return ret;
	284	}
	285
	286	*ptr = tz;
4a16c190	287	devres_add(dev, ptr);
c7fc403e AS	288
	289	return ret;
	290	}
	291	EXPORT_SYMBOL_GPL(devm_thermal_add_hwmon_sysfs);
87743bcf GR	292
87743bcf GR	293	MODULE_IMPORT_NS(HWMON_THERMAL);