Loading...
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 */
36struct 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
44struct thermal_hwmon_attr {
45 struct device_attribute attr;
46 char name[16];
47};
48
49/* one temperature input for each thermal zone */
50struct 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
57static LIST_HEAD(thermal_hwmon_list);
58
59static DEFINE_MUTEX(thermal_hwmon_list_lock);
60
61static ssize_t
62name_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}
67static DEVICE_ATTR(name, 0444, name_show, NULL);
68
69static ssize_t
70temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
71{
72 int temperature;
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
86 return sprintf(buf, "%d\n", temperature);
87}
88
89static ssize_t
90temp_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;
98 int temperature;
99 int ret;
100
101 ret = tz->ops->get_trip_temp(tz, 0, &temperature);
102 if (ret)
103 return ret;
104
105 return sprintf(buf, "%d\n", temperature);
106}
107
108
109static struct thermal_hwmon_device *
110thermal_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 */
126static struct thermal_hwmon_temp *
127thermal_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
143static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
144{
145 int temp;
146 return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
147}
148
149int 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);
168 hwmon->device = hwmon_device_register(NULL);
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
198 if (thermal_zone_crit_temp_valid(tz)) {
199 snprintf(temp->temp_crit.name,
200 sizeof(temp->temp_crit.name),
201 "temp%d_crit", hwmon->count);
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;
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
236void 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);
256 if (thermal_zone_crit_temp_valid(tz))
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}
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 */
36struct 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
44struct thermal_hwmon_attr {
45 struct device_attribute attr;
46 char name[16];
47};
48
49/* one temperature input for each thermal zone */
50struct 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
57static LIST_HEAD(thermal_hwmon_list);
58
59static DEFINE_MUTEX(thermal_hwmon_list_lock);
60
61static ssize_t
62name_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}
67static DEVICE_ATTR(name, 0444, name_show, NULL);
68
69static ssize_t
70temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
71{
72 long temperature;
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
86 return sprintf(buf, "%ld\n", temperature);
87}
88
89static ssize_t
90temp_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;
98 long temperature;
99 int ret;
100
101 ret = tz->ops->get_trip_temp(tz, 0, &temperature);
102 if (ret)
103 return ret;
104
105 return sprintf(buf, "%ld\n", temperature);
106}
107
108
109static struct thermal_hwmon_device *
110thermal_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 */
126static struct thermal_hwmon_temp *
127thermal_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
143int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
144{
145 struct thermal_hwmon_device *hwmon;
146 struct thermal_hwmon_temp *temp;
147 int new_hwmon_device = 1;
148 int result;
149
150 hwmon = thermal_hwmon_lookup_by_type(tz);
151 if (hwmon) {
152 new_hwmon_device = 0;
153 goto register_sys_interface;
154 }
155
156 hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
157 if (!hwmon)
158 return -ENOMEM;
159
160 INIT_LIST_HEAD(&hwmon->tz_list);
161 strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
162 hwmon->device = hwmon_device_register(NULL);
163 if (IS_ERR(hwmon->device)) {
164 result = PTR_ERR(hwmon->device);
165 goto free_mem;
166 }
167 dev_set_drvdata(hwmon->device, hwmon);
168 result = device_create_file(hwmon->device, &dev_attr_name);
169 if (result)
170 goto free_mem;
171
172 register_sys_interface:
173 temp = kzalloc(sizeof(*temp), GFP_KERNEL);
174 if (!temp) {
175 result = -ENOMEM;
176 goto unregister_name;
177 }
178
179 temp->tz = tz;
180 hwmon->count++;
181
182 snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
183 "temp%d_input", hwmon->count);
184 temp->temp_input.attr.attr.name = temp->temp_input.name;
185 temp->temp_input.attr.attr.mode = 0444;
186 temp->temp_input.attr.show = temp_input_show;
187 sysfs_attr_init(&temp->temp_input.attr.attr);
188 result = device_create_file(hwmon->device, &temp->temp_input.attr);
189 if (result)
190 goto free_temp_mem;
191
192 if (tz->ops->get_crit_temp) {
193 unsigned long temperature;
194 if (!tz->ops->get_crit_temp(tz, &temperature)) {
195 snprintf(temp->temp_crit.name,
196 sizeof(temp->temp_crit.name),
197 "temp%d_crit", hwmon->count);
198 temp->temp_crit.attr.attr.name = temp->temp_crit.name;
199 temp->temp_crit.attr.attr.mode = 0444;
200 temp->temp_crit.attr.show = temp_crit_show;
201 sysfs_attr_init(&temp->temp_crit.attr.attr);
202 result = device_create_file(hwmon->device,
203 &temp->temp_crit.attr);
204 if (result)
205 goto unregister_input;
206 }
207 }
208
209 mutex_lock(&thermal_hwmon_list_lock);
210 if (new_hwmon_device)
211 list_add_tail(&hwmon->node, &thermal_hwmon_list);
212 list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
213 mutex_unlock(&thermal_hwmon_list_lock);
214
215 return 0;
216
217 unregister_input:
218 device_remove_file(hwmon->device, &temp->temp_input.attr);
219 free_temp_mem:
220 kfree(temp);
221 unregister_name:
222 if (new_hwmon_device) {
223 device_remove_file(hwmon->device, &dev_attr_name);
224 hwmon_device_unregister(hwmon->device);
225 }
226 free_mem:
227 if (new_hwmon_device)
228 kfree(hwmon);
229
230 return result;
231}
232
233void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
234{
235 struct thermal_hwmon_device *hwmon;
236 struct thermal_hwmon_temp *temp;
237
238 hwmon = thermal_hwmon_lookup_by_type(tz);
239 if (unlikely(!hwmon)) {
240 /* Should never happen... */
241 dev_dbg(&tz->device, "hwmon device lookup failed!\n");
242 return;
243 }
244
245 temp = thermal_hwmon_lookup_temp(hwmon, tz);
246 if (unlikely(!temp)) {
247 /* Should never happen... */
248 dev_dbg(&tz->device, "temperature input lookup failed!\n");
249 return;
250 }
251
252 device_remove_file(hwmon->device, &temp->temp_input.attr);
253 if (tz->ops->get_crit_temp)
254 device_remove_file(hwmon->device, &temp->temp_crit.attr);
255
256 mutex_lock(&thermal_hwmon_list_lock);
257 list_del(&temp->hwmon_node);
258 kfree(temp);
259 if (!list_empty(&hwmon->tz_list)) {
260 mutex_unlock(&thermal_hwmon_list_lock);
261 return;
262 }
263 list_del(&hwmon->node);
264 mutex_unlock(&thermal_hwmon_list_lock);
265
266 device_remove_file(hwmon->device, &dev_attr_name);
267 hwmon_device_unregister(hwmon->device);
268 kfree(hwmon);
269}