[mirror_ubuntu-zesty-kernel.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 <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>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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
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
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 <rui.zhang@intel.com>
	7	* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
	8	*
	9	* Copyright (C) 2013 Texas Instruments
	10	* Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
	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
0dd88793 EV	61	static ssize_t
	62	temp_input_show(struct device dev, struct device_attribute attr, char *buf)
	63	{
17e8351a	64	int temperature;
0dd88793 EV	65	int ret;
	66	struct thermal_hwmon_attr *hwmon_attr
	67	= container_of(attr, struct thermal_hwmon_attr, attr);
	68	struct thermal_hwmon_temp *temp
	69	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	70	temp_input);
	71	struct thermal_zone_device *tz = temp->tz;
	72
	73	ret = thermal_zone_get_temp(tz, &temperature);
	74
	75	if (ret)
	76	return ret;
	77
17e8351a	78	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	79	}
	80
	81	static ssize_t
	82	temp_crit_show(struct device dev, struct device_attribute attr, char *buf)
	83	{
	84	struct thermal_hwmon_attr *hwmon_attr
	85	= container_of(attr, struct thermal_hwmon_attr, attr);
	86	struct thermal_hwmon_temp *temp
	87	= container_of(hwmon_attr, struct thermal_hwmon_temp,
	88	temp_crit);
	89	struct thermal_zone_device *tz = temp->tz;
17e8351a	90	int temperature;
0dd88793 EV	91	int ret;
0dd88793 EV	92
f37fabb8	93	ret = tz->ops->get_crit_temp(tz, &temperature);
0dd88793 EV	94	if (ret)
	95	return ret;
	96
17e8351a	97	return sprintf(buf, "%d\n", temperature);
0dd88793 EV	98	}
	99
	100
	101	static struct thermal_hwmon_device *
	102	thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
	103	{
	104	struct thermal_hwmon_device *hwmon;
	105
	106	mutex_lock(&thermal_hwmon_list_lock);
	107	list_for_each_entry(hwmon, &thermal_hwmon_list, node)
	108	if (!strcmp(hwmon->type, tz->type)) {
	109	mutex_unlock(&thermal_hwmon_list_lock);
	110	return hwmon;
	111	}
	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);
	159	strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
7611fb68 FE	160	hwmon->device = hwmon_device_register_with_info(NULL, hwmon->type,
7611fb68 FE	161	hwmon, NULL, NULL);
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:
7611fb68	214	if (new_hwmon_device)
0dd88793	215	hwmon_device_unregister(hwmon->device);
0dd88793 EV	216	free_mem:
	217	if (new_hwmon_device)
	218	kfree(hwmon);
	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... */
	232	dev_dbg(&tz->device, "hwmon device lookup failed!\n");
	233	return;
	234	}
	235
	236	temp = thermal_hwmon_lookup_temp(hwmon, tz);
	237	if (unlikely(!temp)) {
	238	/* Should never happen... */
	239	dev_dbg(&tz->device, "temperature input lookup failed!\n");
	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);