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1/* Texas Instruments TMP102 SMBus temperature sensor driver
2 *
3 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/slab.h>
23#include <linux/i2c.h>
24#include <linux/hwmon.h>
25#include <linux/hwmon-sysfs.h>
26#include <linux/err.h>
27#include <linux/mutex.h>
28#include <linux/device.h>
29#include <linux/jiffies.h>
30#include <linux/thermal.h>
31#include <linux/of.h>
32
33#define DRIVER_NAME "tmp102"
34
35#define TMP102_TEMP_REG 0x00
36#define TMP102_CONF_REG 0x01
37/* note: these bit definitions are byte swapped */
38#define TMP102_CONF_SD 0x0100
39#define TMP102_CONF_TM 0x0200
40#define TMP102_CONF_POL 0x0400
41#define TMP102_CONF_F0 0x0800
42#define TMP102_CONF_F1 0x1000
43#define TMP102_CONF_R0 0x2000
44#define TMP102_CONF_R1 0x4000
45#define TMP102_CONF_OS 0x8000
46#define TMP102_CONF_EM 0x0010
47#define TMP102_CONF_AL 0x0020
48#define TMP102_CONF_CR0 0x0040
49#define TMP102_CONF_CR1 0x0080
50#define TMP102_TLOW_REG 0x02
51#define TMP102_THIGH_REG 0x03
52
53struct tmp102 {
54 struct i2c_client *client;
55 struct device *hwmon_dev;
56 struct thermal_zone_device *tz;
57 struct mutex lock;
58 u16 config_orig;
59 unsigned long last_update;
60 int temp[3];
61 bool first_time;
62};
63
64/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
65static inline int tmp102_reg_to_mC(s16 val)
66{
67 return ((val & ~0x01) * 1000) / 128;
68}
69
70/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
71static inline u16 tmp102_mC_to_reg(int val)
72{
73 return (val * 128) / 1000;
74}
75
76static const u8 tmp102_reg[] = {
77 TMP102_TEMP_REG,
78 TMP102_TLOW_REG,
79 TMP102_THIGH_REG,
80};
81
82static struct tmp102 *tmp102_update_device(struct device *dev)
83{
84 struct tmp102 *tmp102 = dev_get_drvdata(dev);
85 struct i2c_client *client = tmp102->client;
86
87 mutex_lock(&tmp102->lock);
88 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
89 int i;
90 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
91 int status = i2c_smbus_read_word_swapped(client,
92 tmp102_reg[i]);
93 if (status > -1)
94 tmp102->temp[i] = tmp102_reg_to_mC(status);
95 }
96 tmp102->last_update = jiffies;
97 tmp102->first_time = false;
98 }
99 mutex_unlock(&tmp102->lock);
100 return tmp102;
101}
102
103static int tmp102_read_temp(void *dev, int *temp)
104{
105 struct tmp102 *tmp102 = tmp102_update_device(dev);
106
107 /* Is it too early even to return a conversion? */
108 if (tmp102->first_time) {
109 dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
110 return -EAGAIN;
111 }
112
113 *temp = tmp102->temp[0];
114
115 return 0;
116}
117
118static ssize_t tmp102_show_temp(struct device *dev,
119 struct device_attribute *attr,
120 char *buf)
121{
122 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
123 struct tmp102 *tmp102 = tmp102_update_device(dev);
124
125 /* Is it too early even to return a read? */
126 if (tmp102->first_time)
127 return -EAGAIN;
128
129 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
130}
131
132static ssize_t tmp102_set_temp(struct device *dev,
133 struct device_attribute *attr,
134 const char *buf, size_t count)
135{
136 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
137 struct tmp102 *tmp102 = dev_get_drvdata(dev);
138 struct i2c_client *client = tmp102->client;
139 long val;
140 int status;
141
142 if (kstrtol(buf, 10, &val) < 0)
143 return -EINVAL;
144 val = clamp_val(val, -256000, 255000);
145
146 mutex_lock(&tmp102->lock);
147 tmp102->temp[sda->index] = val;
148 status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
149 tmp102_mC_to_reg(val));
150 mutex_unlock(&tmp102->lock);
151 return status ? : count;
152}
153
154static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
155
156static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
157 tmp102_set_temp, 1);
158
159static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
160 tmp102_set_temp, 2);
161
162static struct attribute *tmp102_attrs[] = {
163 &sensor_dev_attr_temp1_input.dev_attr.attr,
164 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
165 &sensor_dev_attr_temp1_max.dev_attr.attr,
166 NULL
167};
168ATTRIBUTE_GROUPS(tmp102);
169
170#define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
171#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
172
173static const struct thermal_zone_of_device_ops tmp102_of_thermal_ops = {
174 .get_temp = tmp102_read_temp,
175};
176
177static int tmp102_probe(struct i2c_client *client,
178 const struct i2c_device_id *id)
179{
180 struct device *dev = &client->dev;
181 struct device *hwmon_dev;
182 struct tmp102 *tmp102;
183 int status;
184
185 if (!i2c_check_functionality(client->adapter,
186 I2C_FUNC_SMBUS_WORD_DATA)) {
187 dev_err(dev,
188 "adapter doesn't support SMBus word transactions\n");
189 return -ENODEV;
190 }
191
192 tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
193 if (!tmp102)
194 return -ENOMEM;
195
196 i2c_set_clientdata(client, tmp102);
197 tmp102->client = client;
198
199 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
200 if (status < 0) {
201 dev_err(dev, "error reading config register\n");
202 return status;
203 }
204 tmp102->config_orig = status;
205 status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
206 TMP102_CONFIG);
207 if (status < 0) {
208 dev_err(dev, "error writing config register\n");
209 goto fail_restore_config;
210 }
211 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
212 if (status < 0) {
213 dev_err(dev, "error reading config register\n");
214 goto fail_restore_config;
215 }
216 status &= ~TMP102_CONFIG_RD_ONLY;
217 if (status != TMP102_CONFIG) {
218 dev_err(dev, "config settings did not stick\n");
219 status = -ENODEV;
220 goto fail_restore_config;
221 }
222 tmp102->last_update = jiffies;
223 /* Mark that we are not ready with data until conversion is complete */
224 tmp102->first_time = true;
225 mutex_init(&tmp102->lock);
226
227 hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
228 tmp102, tmp102_groups);
229 if (IS_ERR(hwmon_dev)) {
230 dev_dbg(dev, "unable to register hwmon device\n");
231 status = PTR_ERR(hwmon_dev);
232 goto fail_restore_config;
233 }
234 tmp102->hwmon_dev = hwmon_dev;
235 tmp102->tz = thermal_zone_of_sensor_register(hwmon_dev, 0, hwmon_dev,
236 &tmp102_of_thermal_ops);
237 if (IS_ERR(tmp102->tz))
238 tmp102->tz = NULL;
239
240 dev_info(dev, "initialized\n");
241
242 return 0;
243
244fail_restore_config:
245 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
246 tmp102->config_orig);
247 return status;
248}
249
250static int tmp102_remove(struct i2c_client *client)
251{
252 struct tmp102 *tmp102 = i2c_get_clientdata(client);
253
254 thermal_zone_of_sensor_unregister(tmp102->hwmon_dev, tmp102->tz);
255 hwmon_device_unregister(tmp102->hwmon_dev);
256
257 /* Stop monitoring if device was stopped originally */
258 if (tmp102->config_orig & TMP102_CONF_SD) {
259 int config;
260
261 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
262 if (config >= 0)
263 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
264 config | TMP102_CONF_SD);
265 }
266
267 return 0;
268}
269
270#ifdef CONFIG_PM_SLEEP
271static int tmp102_suspend(struct device *dev)
272{
273 struct i2c_client *client = to_i2c_client(dev);
274 int config;
275
276 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
277 if (config < 0)
278 return config;
279
280 config |= TMP102_CONF_SD;
281 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
282}
283
284static int tmp102_resume(struct device *dev)
285{
286 struct i2c_client *client = to_i2c_client(dev);
287 int config;
288
289 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
290 if (config < 0)
291 return config;
292
293 config &= ~TMP102_CONF_SD;
294 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
295}
296#endif /* CONFIG_PM */
297
298static SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
299
300static const struct i2c_device_id tmp102_id[] = {
301 { "tmp102", 0 },
302 { }
303};
304MODULE_DEVICE_TABLE(i2c, tmp102_id);
305
306static struct i2c_driver tmp102_driver = {
307 .driver.name = DRIVER_NAME,
308 .driver.pm = &tmp102_dev_pm_ops,
309 .probe = tmp102_probe,
310 .remove = tmp102_remove,
311 .id_table = tmp102_id,
312};
313
314module_i2c_driver(tmp102_driver);
315
316MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
317MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
318MODULE_LICENSE("GPL");
1/* Texas Instruments TMP102 SMBus temperature sensor driver
2 *
3 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/slab.h>
23#include <linux/i2c.h>
24#include <linux/hwmon.h>
25#include <linux/hwmon-sysfs.h>
26#include <linux/err.h>
27#include <linux/mutex.h>
28#include <linux/device.h>
29
30#define DRIVER_NAME "tmp102"
31
32#define TMP102_TEMP_REG 0x00
33#define TMP102_CONF_REG 0x01
34/* note: these bit definitions are byte swapped */
35#define TMP102_CONF_SD 0x0100
36#define TMP102_CONF_TM 0x0200
37#define TMP102_CONF_POL 0x0400
38#define TMP102_CONF_F0 0x0800
39#define TMP102_CONF_F1 0x1000
40#define TMP102_CONF_R0 0x2000
41#define TMP102_CONF_R1 0x4000
42#define TMP102_CONF_OS 0x8000
43#define TMP102_CONF_EM 0x0010
44#define TMP102_CONF_AL 0x0020
45#define TMP102_CONF_CR0 0x0040
46#define TMP102_CONF_CR1 0x0080
47#define TMP102_TLOW_REG 0x02
48#define TMP102_THIGH_REG 0x03
49
50struct tmp102 {
51 struct device *hwmon_dev;
52 struct mutex lock;
53 u16 config_orig;
54 unsigned long last_update;
55 int temp[3];
56};
57
58/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
59static inline int tmp102_reg_to_mC(s16 val)
60{
61 return ((val & ~0x01) * 1000) / 128;
62}
63
64/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
65static inline u16 tmp102_mC_to_reg(int val)
66{
67 return (val * 128) / 1000;
68}
69
70static const u8 tmp102_reg[] = {
71 TMP102_TEMP_REG,
72 TMP102_TLOW_REG,
73 TMP102_THIGH_REG,
74};
75
76static struct tmp102 *tmp102_update_device(struct i2c_client *client)
77{
78 struct tmp102 *tmp102 = i2c_get_clientdata(client);
79
80 mutex_lock(&tmp102->lock);
81 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
82 int i;
83 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
84 int status = i2c_smbus_read_word_swapped(client,
85 tmp102_reg[i]);
86 if (status > -1)
87 tmp102->temp[i] = tmp102_reg_to_mC(status);
88 }
89 tmp102->last_update = jiffies;
90 }
91 mutex_unlock(&tmp102->lock);
92 return tmp102;
93}
94
95static ssize_t tmp102_show_temp(struct device *dev,
96 struct device_attribute *attr,
97 char *buf)
98{
99 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
100 struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
101
102 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
103}
104
105static ssize_t tmp102_set_temp(struct device *dev,
106 struct device_attribute *attr,
107 const char *buf, size_t count)
108{
109 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
110 struct i2c_client *client = to_i2c_client(dev);
111 struct tmp102 *tmp102 = i2c_get_clientdata(client);
112 long val;
113 int status;
114
115 if (kstrtol(buf, 10, &val) < 0)
116 return -EINVAL;
117 val = SENSORS_LIMIT(val, -256000, 255000);
118
119 mutex_lock(&tmp102->lock);
120 tmp102->temp[sda->index] = val;
121 status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
122 tmp102_mC_to_reg(val));
123 mutex_unlock(&tmp102->lock);
124 return status ? : count;
125}
126
127static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
128
129static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
130 tmp102_set_temp, 1);
131
132static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
133 tmp102_set_temp, 2);
134
135static struct attribute *tmp102_attributes[] = {
136 &sensor_dev_attr_temp1_input.dev_attr.attr,
137 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
138 &sensor_dev_attr_temp1_max.dev_attr.attr,
139 NULL
140};
141
142static const struct attribute_group tmp102_attr_group = {
143 .attrs = tmp102_attributes,
144};
145
146#define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
147#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
148
149static int __devinit tmp102_probe(struct i2c_client *client,
150 const struct i2c_device_id *id)
151{
152 struct tmp102 *tmp102;
153 int status;
154
155 if (!i2c_check_functionality(client->adapter,
156 I2C_FUNC_SMBUS_WORD_DATA)) {
157 dev_err(&client->dev, "adapter doesn't support SMBus word "
158 "transactions\n");
159 return -ENODEV;
160 }
161
162 tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
163 if (!tmp102) {
164 dev_dbg(&client->dev, "kzalloc failed\n");
165 return -ENOMEM;
166 }
167 i2c_set_clientdata(client, tmp102);
168
169 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
170 if (status < 0) {
171 dev_err(&client->dev, "error reading config register\n");
172 goto fail_free;
173 }
174 tmp102->config_orig = status;
175 status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
176 TMP102_CONFIG);
177 if (status < 0) {
178 dev_err(&client->dev, "error writing config register\n");
179 goto fail_restore_config;
180 }
181 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
182 if (status < 0) {
183 dev_err(&client->dev, "error reading config register\n");
184 goto fail_restore_config;
185 }
186 status &= ~TMP102_CONFIG_RD_ONLY;
187 if (status != TMP102_CONFIG) {
188 dev_err(&client->dev, "config settings did not stick\n");
189 status = -ENODEV;
190 goto fail_restore_config;
191 }
192 tmp102->last_update = jiffies - HZ;
193 mutex_init(&tmp102->lock);
194
195 status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
196 if (status) {
197 dev_dbg(&client->dev, "could not create sysfs files\n");
198 goto fail_restore_config;
199 }
200 tmp102->hwmon_dev = hwmon_device_register(&client->dev);
201 if (IS_ERR(tmp102->hwmon_dev)) {
202 dev_dbg(&client->dev, "unable to register hwmon device\n");
203 status = PTR_ERR(tmp102->hwmon_dev);
204 goto fail_remove_sysfs;
205 }
206
207 dev_info(&client->dev, "initialized\n");
208
209 return 0;
210
211fail_remove_sysfs:
212 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
213fail_restore_config:
214 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
215 tmp102->config_orig);
216fail_free:
217 kfree(tmp102);
218
219 return status;
220}
221
222static int __devexit tmp102_remove(struct i2c_client *client)
223{
224 struct tmp102 *tmp102 = i2c_get_clientdata(client);
225
226 hwmon_device_unregister(tmp102->hwmon_dev);
227 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
228
229 /* Stop monitoring if device was stopped originally */
230 if (tmp102->config_orig & TMP102_CONF_SD) {
231 int config;
232
233 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
234 if (config >= 0)
235 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
236 config | TMP102_CONF_SD);
237 }
238
239 kfree(tmp102);
240
241 return 0;
242}
243
244#ifdef CONFIG_PM
245static int tmp102_suspend(struct device *dev)
246{
247 struct i2c_client *client = to_i2c_client(dev);
248 int config;
249
250 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
251 if (config < 0)
252 return config;
253
254 config |= TMP102_CONF_SD;
255 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
256}
257
258static int tmp102_resume(struct device *dev)
259{
260 struct i2c_client *client = to_i2c_client(dev);
261 int config;
262
263 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
264 if (config < 0)
265 return config;
266
267 config &= ~TMP102_CONF_SD;
268 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
269}
270
271static const struct dev_pm_ops tmp102_dev_pm_ops = {
272 .suspend = tmp102_suspend,
273 .resume = tmp102_resume,
274};
275
276#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
277#else
278#define TMP102_DEV_PM_OPS NULL
279#endif /* CONFIG_PM */
280
281static const struct i2c_device_id tmp102_id[] = {
282 { "tmp102", 0 },
283 { }
284};
285MODULE_DEVICE_TABLE(i2c, tmp102_id);
286
287static struct i2c_driver tmp102_driver = {
288 .driver.name = DRIVER_NAME,
289 .driver.pm = TMP102_DEV_PM_OPS,
290 .probe = tmp102_probe,
291 .remove = __devexit_p(tmp102_remove),
292 .id_table = tmp102_id,
293};
294
295module_i2c_driver(tmp102_driver);
296
297MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
298MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
299MODULE_LICENSE("GPL");