[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"

/* 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 thermal_zone_device *tz)
{
	struct thermal_zone_device **ptr;
	int ret;

	ptr = devres_alloc(devm_thermal_hwmon_release, sizeof(*ptr),
			   GFP_KERNEL);
	if (!ptr)
		return -ENOMEM;

	ret = thermal_add_hwmon_sysfs(tz);
	if (ret) {
		devres_free(ptr);
		return ret;
	}

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