[linux.git] / drivers / thermal / thermal_hwmon.c

/*
 *  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 <[email protected]>
 *  Copyright (C) 2008 Sujith Thomas <[email protected]>
 *
 *  Copyright (C) 2013 Texas Instruments
 *  Copyright (C) 2013 Eduardo Valentin <[email protected]>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */
#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
name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct thermal_hwmon_device *hwmon = dev_get_drvdata(dev);
	return sprintf(buf, "%s\n", hwmon->type);
}
static DEVICE_ATTR(name, 0444, name_show, NULL);

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_trip_temp(tz, 0, &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(NULL);
	if (IS_ERR(hwmon->device)) {
		result = PTR_ERR(hwmon->device);
		goto free_mem;
	}
	dev_set_drvdata(hwmon->device, hwmon);
	result = device_create_file(hwmon->device, &dev_attr_name);
	if (result)
		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) {
		device_remove_file(hwmon->device, &dev_attr_name);
		hwmon_device_unregister(hwmon->device);
	}
 free_mem:
	if (new_hwmon_device)
		kfree(hwmon);

	return result;
}

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);

	device_remove_file(hwmon->device, &dev_attr_name);
	hwmon_device_unregister(hwmon->device);
	kfree(hwmon);
}
Commit	Line	Data
0dd88793 EV	1	/*
	2	* thermal_hwmon.c - Generic Thermal Management hwmon support.
	3	*
	4	* Code based on Intel thermal_core.c. Copyrights of the original code:
	5	* Copyright (C) 2008 Intel Corp
	6	* Copyright (C) 2008 Zhang Rui <[email protected]>
	7	* Copyright (C) 2008 Sujith Thomas <[email protected]>
	8	*
	9	* Copyright (C) 2013 Texas Instruments
	10	* Copyright (C) 2013 Eduardo Valentin <[email protected]>
	11	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License as published by
	15	* the Free Software Foundation; version 2 of the License.
	16	*
	17	* This program is distributed in the hope that it will be useful, but
	18	* WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	20	* General Public License for more details.
	21	*
	22	* You should have received a copy of the GNU General Public License along
	23	* with this program; if not, write to the Free Software Foundation, Inc.,
	24	* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
	25	*
	26	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	27	*/
	28	#include <linux/hwmon.h>
	29	#include <linux/thermal.h>
	30	#include <linux/slab.h>
	31	#include <linux/err.h>
	32	#include "thermal_hwmon.h"
	33
	34	/* hwmon sys I/F */
	35	/* thermal zone devices with the same type share one hwmon device */
	36	struct thermal_hwmon_device {
	37	char type[THERMAL_NAME_LENGTH];
	38	struct device *device;
	39	int count;
	40	struct list_head tz_list;
	41	struct list_head node;
	42	};
	43
	44	struct thermal_hwmon_attr {
	45	struct device_attribute attr;
	46	char name[16];
	47	};
	48
	49	/* one temperature input for each thermal zone */
	50	struct thermal_hwmon_temp {
	51	struct list_head hwmon_node;
	52	struct thermal_zone_device *tz;
	53	struct thermal_hwmon_attr temp_input; /* hwmon sys attr */
	54	struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */
	55	};
	56
	57	static LIST_HEAD(thermal_hwmon_list);
	58
	59	static DEFINE_MUTEX(thermal_hwmon_list_lock);
	60
	61	static ssize_t
	62	name_show(struct device dev, struct device_attribute attr, char *buf)
	63	{
	64	struct thermal_hwmon_device *hwmon = dev_get_drvdata(dev);
65	return sprintf(buf, "%s\n", hwmon->type);
66	}
67	static DEVICE_ATTR(name, 0444, name_show, NULL);
68
69	static ssize_t
70	temp_input_show(struct device dev, struct device_attribute attr, char *buf)
71	{
17e8351a	72	int temperature;
0dd88793 EV	73	int ret;
	74	struct thermal_hwmon_attr *hwmon_attr
	75	= container_of(attr, struct thermal_hwmon_attr, attr);
	76	struct thermal_hwmon_temp *temp
	77	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	78	temp_input);
	79	struct thermal_zone_device *tz = temp->tz;
	80
	81	ret = thermal_zone_get_temp(tz, &temperature);
	82
	83	if (ret)
	84	return ret;
	85
17e8351a	86	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	87	}
	88
	89	static ssize_t
	90	temp_crit_show(struct device dev, struct device_attribute attr, char *buf)
	91	{
	92	struct thermal_hwmon_attr *hwmon_attr
	93	= container_of(attr, struct thermal_hwmon_attr, attr);
	94	struct thermal_hwmon_temp *temp
	95	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	96	temp_crit);
	97	struct thermal_zone_device *tz = temp->tz;
17e8351a	98	int temperature;
0dd88793 EV	99	int ret;
	100
	101	ret = tz->ops->get_trip_temp(tz, 0, &temperature);
	102	if (ret)
	103	return ret;
	104
17e8351a	105	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	106	}
	107
	108
	109	static struct thermal_hwmon_device *
	110	thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
	111	{
	112	struct thermal_hwmon_device *hwmon;
	113
	114	mutex_lock(&thermal_hwmon_list_lock);
	115	list_for_each_entry(hwmon, &thermal_hwmon_list, node)
	116	if (!strcmp(hwmon->type, tz->type)) {
	117	mutex_unlock(&thermal_hwmon_list_lock);
	118	return hwmon;
	119	}
	120	mutex_unlock(&thermal_hwmon_list_lock);
	121
	122	return NULL;
	123	}
	124
	125	/* Find the temperature input matching a given thermal zone */
	126	static struct thermal_hwmon_temp *
	127	thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,
	128	const struct thermal_zone_device *tz)
	129	{
	130	struct thermal_hwmon_temp *temp;
	131
	132	mutex_lock(&thermal_hwmon_list_lock);
	133	list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)
	134	if (temp->tz == tz) {
	135	mutex_unlock(&thermal_hwmon_list_lock);
	136	return temp;
	137	}
	138	mutex_unlock(&thermal_hwmon_list_lock);
	139
	140	return NULL;
	141	}
	142
e8db5d67 AL	143	static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
e8db5d67 AL	144	{
17e8351a	145	int temp;
e8db5d67 AL	146	return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
	147	}
	148
0dd88793 EV	149	int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
	150	{
	151	struct thermal_hwmon_device *hwmon;
	152	struct thermal_hwmon_temp *temp;
	153	int new_hwmon_device = 1;
	154	int result;
	155
	156	hwmon = thermal_hwmon_lookup_by_type(tz);
	157	if (hwmon) {
	158	new_hwmon_device = 0;
	159	goto register_sys_interface;
	160	}
	161
	162	hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
	163	if (!hwmon)
	164	return -ENOMEM;
	165
	166	INIT_LIST_HEAD(&hwmon->tz_list);
	167	strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
6ddcb7e6	168	hwmon->device = hwmon_device_register(NULL);
0dd88793 EV	169	if (IS_ERR(hwmon->device)) {
	170	result = PTR_ERR(hwmon->device);
	171	goto free_mem;
	172	}
	173	dev_set_drvdata(hwmon->device, hwmon);
	174	result = device_create_file(hwmon->device, &dev_attr_name);
	175	if (result)
	176	goto free_mem;
	177
	178	register_sys_interface:
	179	temp = kzalloc(sizeof(*temp), GFP_KERNEL);
	180	if (!temp) {
	181	result = -ENOMEM;
	182	goto unregister_name;
	183	}
	184
	185	temp->tz = tz;
	186	hwmon->count++;
	187
	188	snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
	189	"temp%d_input", hwmon->count);
	190	temp->temp_input.attr.attr.name = temp->temp_input.name;
	191	temp->temp_input.attr.attr.mode = 0444;
	192	temp->temp_input.attr.show = temp_input_show;
	193	sysfs_attr_init(&temp->temp_input.attr.attr);
	194	result = device_create_file(hwmon->device, &temp->temp_input.attr);
	195	if (result)
	196	goto free_temp_mem;
	197
e8db5d67 AL	198	if (thermal_zone_crit_temp_valid(tz)) {
	199	snprintf(temp->temp_crit.name,
	200	sizeof(temp->temp_crit.name),
0dd88793	201	"temp%d_crit", hwmon->count);
e8db5d67 AL	202	temp->temp_crit.attr.attr.name = temp->temp_crit.name;
	203	temp->temp_crit.attr.attr.mode = 0444;
	204	temp->temp_crit.attr.show = temp_crit_show;
	205	sysfs_attr_init(&temp->temp_crit.attr.attr);
	206	result = device_create_file(hwmon->device,
	207	&temp->temp_crit.attr);
	208	if (result)
	209	goto unregister_input;
0dd88793 EV	210	}
	211
	212	mutex_lock(&thermal_hwmon_list_lock);
	213	if (new_hwmon_device)
	214	list_add_tail(&hwmon->node, &thermal_hwmon_list);
	215	list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
	216	mutex_unlock(&thermal_hwmon_list_lock);
	217
	218	return 0;
	219
	220	unregister_input:
	221	device_remove_file(hwmon->device, &temp->temp_input.attr);
	222	free_temp_mem:
	223	kfree(temp);
	224	unregister_name:
	225	if (new_hwmon_device) {
	226	device_remove_file(hwmon->device, &dev_attr_name);
	227	hwmon_device_unregister(hwmon->device);
	228	}
	229	free_mem:
	230	if (new_hwmon_device)
	231	kfree(hwmon);
	232
	233	return result;
	234	}
	235
	236	void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
	237	{
	238	struct thermal_hwmon_device *hwmon;
	239	struct thermal_hwmon_temp *temp;
	240
	241	hwmon = thermal_hwmon_lookup_by_type(tz);
	242	if (unlikely(!hwmon)) {
	243	/* Should never happen... */
	244	dev_dbg(&tz->device, "hwmon device lookup failed!\n");
	245	return;
	246	}
	247
	248	temp = thermal_hwmon_lookup_temp(hwmon, tz);
	249	if (unlikely(!temp)) {
	250	/* Should never happen... */
	251	dev_dbg(&tz->device, "temperature input lookup failed!\n");
	252	return;
	253	}
	254
	255	device_remove_file(hwmon->device, &temp->temp_input.attr);
e8db5d67	256	if (thermal_zone_crit_temp_valid(tz))
0dd88793 EV	257	device_remove_file(hwmon->device, &temp->temp_crit.attr);
	258
	259	mutex_lock(&thermal_hwmon_list_lock);
	260	list_del(&temp->hwmon_node);
	261	kfree(temp);
	262	if (!list_empty(&hwmon->tz_list)) {
	263	mutex_unlock(&thermal_hwmon_list_lock);
	264	return;
	265	}
	266	list_del(&hwmon->node);
	267	mutex_unlock(&thermal_hwmon_list_lock);
	268
	269	device_remove_file(hwmon->device, &dev_attr_name);
	270	hwmon_device_unregister(hwmon->device);
	271	kfree(hwmon);
	272	}