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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
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/* SMBus specifies low byte first, but the TMP102 returns high byte first,
59 * so we have to swab16 the values */
60static inline int tmp102_read_reg(struct i2c_client *client, u8 reg)
61{
62 int result = i2c_smbus_read_word_data(client, reg);
63 return result < 0 ? result : swab16(result);
64}
65
66static inline int tmp102_write_reg(struct i2c_client *client, u8 reg, u16 val)
67{
68 return i2c_smbus_write_word_data(client, reg, swab16(val));
69}
70
71/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
72static inline int tmp102_reg_to_mC(s16 val)
73{
74 return ((val & ~0x01) * 1000) / 128;
75}
76
77/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
78static inline u16 tmp102_mC_to_reg(int val)
79{
80 return (val * 128) / 1000;
81}
82
83static const u8 tmp102_reg[] = {
84 TMP102_TEMP_REG,
85 TMP102_TLOW_REG,
86 TMP102_THIGH_REG,
87};
88
89static struct tmp102 *tmp102_update_device(struct i2c_client *client)
90{
91 struct tmp102 *tmp102 = i2c_get_clientdata(client);
92
93 mutex_lock(&tmp102->lock);
94 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
95 int i;
96 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
97 int status = tmp102_read_reg(client, tmp102_reg[i]);
98 if (status > -1)
99 tmp102->temp[i] = tmp102_reg_to_mC(status);
100 }
101 tmp102->last_update = jiffies;
102 }
103 mutex_unlock(&tmp102->lock);
104 return tmp102;
105}
106
107static ssize_t tmp102_show_temp(struct device *dev,
108 struct device_attribute *attr,
109 char *buf)
110{
111 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
112 struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
113
114 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
115}
116
117static ssize_t tmp102_set_temp(struct device *dev,
118 struct device_attribute *attr,
119 const char *buf, size_t count)
120{
121 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
122 struct i2c_client *client = to_i2c_client(dev);
123 struct tmp102 *tmp102 = i2c_get_clientdata(client);
124 long val;
125 int status;
126
127 if (strict_strtol(buf, 10, &val) < 0)
128 return -EINVAL;
129 val = SENSORS_LIMIT(val, -256000, 255000);
130
131 mutex_lock(&tmp102->lock);
132 tmp102->temp[sda->index] = val;
133 status = tmp102_write_reg(client, tmp102_reg[sda->index],
134 tmp102_mC_to_reg(val));
135 mutex_unlock(&tmp102->lock);
136 return status ? : count;
137}
138
139static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
140
141static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
142 tmp102_set_temp, 1);
143
144static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
145 tmp102_set_temp, 2);
146
147static struct attribute *tmp102_attributes[] = {
148 &sensor_dev_attr_temp1_input.dev_attr.attr,
149 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
150 &sensor_dev_attr_temp1_max.dev_attr.attr,
151 NULL
152};
153
154static const struct attribute_group tmp102_attr_group = {
155 .attrs = tmp102_attributes,
156};
157
158#define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
159#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
160
161static int __devinit tmp102_probe(struct i2c_client *client,
162 const struct i2c_device_id *id)
163{
164 struct tmp102 *tmp102;
165 int status;
166
167 if (!i2c_check_functionality(client->adapter,
168 I2C_FUNC_SMBUS_WORD_DATA)) {
169 dev_err(&client->dev, "adapter doesn't support SMBus word "
170 "transactions\n");
171 return -ENODEV;
172 }
173
174 tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
175 if (!tmp102) {
176 dev_dbg(&client->dev, "kzalloc failed\n");
177 return -ENOMEM;
178 }
179 i2c_set_clientdata(client, tmp102);
180
181 status = tmp102_read_reg(client, TMP102_CONF_REG);
182 if (status < 0) {
183 dev_err(&client->dev, "error reading config register\n");
184 goto fail_free;
185 }
186 tmp102->config_orig = status;
187 status = tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONFIG);
188 if (status < 0) {
189 dev_err(&client->dev, "error writing config register\n");
190 goto fail_restore_config;
191 }
192 status = tmp102_read_reg(client, TMP102_CONF_REG);
193 if (status < 0) {
194 dev_err(&client->dev, "error reading config register\n");
195 goto fail_restore_config;
196 }
197 status &= ~TMP102_CONFIG_RD_ONLY;
198 if (status != TMP102_CONFIG) {
199 dev_err(&client->dev, "config settings did not stick\n");
200 status = -ENODEV;
201 goto fail_restore_config;
202 }
203 tmp102->last_update = jiffies - HZ;
204 mutex_init(&tmp102->lock);
205
206 status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
207 if (status) {
208 dev_dbg(&client->dev, "could not create sysfs files\n");
209 goto fail_restore_config;
210 }
211 tmp102->hwmon_dev = hwmon_device_register(&client->dev);
212 if (IS_ERR(tmp102->hwmon_dev)) {
213 dev_dbg(&client->dev, "unable to register hwmon device\n");
214 status = PTR_ERR(tmp102->hwmon_dev);
215 goto fail_remove_sysfs;
216 }
217
218 dev_info(&client->dev, "initialized\n");
219
220 return 0;
221
222fail_remove_sysfs:
223 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
224fail_restore_config:
225 tmp102_write_reg(client, TMP102_CONF_REG, tmp102->config_orig);
226fail_free:
227 kfree(tmp102);
228
229 return status;
230}
231
232static int __devexit tmp102_remove(struct i2c_client *client)
233{
234 struct tmp102 *tmp102 = i2c_get_clientdata(client);
235
236 hwmon_device_unregister(tmp102->hwmon_dev);
237 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
238
239 /* Stop monitoring if device was stopped originally */
240 if (tmp102->config_orig & TMP102_CONF_SD) {
241 int config;
242
243 config = tmp102_read_reg(client, TMP102_CONF_REG);
244 if (config >= 0)
245 tmp102_write_reg(client, TMP102_CONF_REG,
246 config | TMP102_CONF_SD);
247 }
248
249 kfree(tmp102);
250
251 return 0;
252}
253
254#ifdef CONFIG_PM
255static int tmp102_suspend(struct device *dev)
256{
257 struct i2c_client *client = to_i2c_client(dev);
258 int config;
259
260 config = tmp102_read_reg(client, TMP102_CONF_REG);
261 if (config < 0)
262 return config;
263
264 config |= TMP102_CONF_SD;
265 return tmp102_write_reg(client, TMP102_CONF_REG, config);
266}
267
268static int tmp102_resume(struct device *dev)
269{
270 struct i2c_client *client = to_i2c_client(dev);
271 int config;
272
273 config = tmp102_read_reg(client, TMP102_CONF_REG);
274 if (config < 0)
275 return config;
276
277 config &= ~TMP102_CONF_SD;
278 return tmp102_write_reg(client, TMP102_CONF_REG, config);
279}
280
281static const struct dev_pm_ops tmp102_dev_pm_ops = {
282 .suspend = tmp102_suspend,
283 .resume = tmp102_resume,
284};
285
286#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
287#else
288#define TMP102_DEV_PM_OPS NULL
289#endif /* CONFIG_PM */
290
291static const struct i2c_device_id tmp102_id[] = {
292 { "tmp102", 0 },
293 { }
294};
295MODULE_DEVICE_TABLE(i2c, tmp102_id);
296
297static struct i2c_driver tmp102_driver = {
298 .driver.name = DRIVER_NAME,
299 .driver.pm = TMP102_DEV_PM_OPS,
300 .probe = tmp102_probe,
301 .remove = __devexit_p(tmp102_remove),
302 .id_table = tmp102_id,
303};
304
305static int __init tmp102_init(void)
306{
307 return i2c_add_driver(&tmp102_driver);
308}
309module_init(tmp102_init);
310
311static void __exit tmp102_exit(void)
312{
313 i2c_del_driver(&tmp102_driver);
314}
315module_exit(tmp102_exit);
316
317MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
318MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
319MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Texas Instruments TMP102 SMBus temperature sensor driver
3 *
4 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
5 */
6
7#include <linux/delay.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/i2c.h>
12#include <linux/hwmon.h>
13#include <linux/hwmon-sysfs.h>
14#include <linux/err.h>
15#include <linux/mutex.h>
16#include <linux/device.h>
17#include <linux/jiffies.h>
18#include <linux/regmap.h>
19#include <linux/of.h>
20
21#define DRIVER_NAME "tmp102"
22
23#define TMP102_TEMP_REG 0x00
24#define TMP102_CONF_REG 0x01
25/* note: these bit definitions are byte swapped */
26#define TMP102_CONF_SD 0x0100
27#define TMP102_CONF_TM 0x0200
28#define TMP102_CONF_POL 0x0400
29#define TMP102_CONF_F0 0x0800
30#define TMP102_CONF_F1 0x1000
31#define TMP102_CONF_R0 0x2000
32#define TMP102_CONF_R1 0x4000
33#define TMP102_CONF_OS 0x8000
34#define TMP102_CONF_EM 0x0010
35#define TMP102_CONF_AL 0x0020
36#define TMP102_CONF_CR0 0x0040
37#define TMP102_CONF_CR1 0x0080
38#define TMP102_TLOW_REG 0x02
39#define TMP102_THIGH_REG 0x03
40
41#define TMP102_CONFREG_MASK (TMP102_CONF_SD | TMP102_CONF_TM | \
42 TMP102_CONF_POL | TMP102_CONF_F0 | \
43 TMP102_CONF_F1 | TMP102_CONF_OS | \
44 TMP102_CONF_EM | TMP102_CONF_AL | \
45 TMP102_CONF_CR0 | TMP102_CONF_CR1)
46
47#define TMP102_CONFIG_CLEAR (TMP102_CONF_SD | TMP102_CONF_OS | \
48 TMP102_CONF_CR0)
49#define TMP102_CONFIG_SET (TMP102_CONF_TM | TMP102_CONF_EM | \
50 TMP102_CONF_CR1)
51
52#define CONVERSION_TIME_MS 35 /* in milli-seconds */
53
54struct tmp102 {
55 struct regmap *regmap;
56 u16 config_orig;
57 unsigned long ready_time;
58};
59
60/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
61static inline int tmp102_reg_to_mC(s16 val)
62{
63 return ((val & ~0x01) * 1000) / 128;
64}
65
66/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
67static inline u16 tmp102_mC_to_reg(int val)
68{
69 return (val * 128) / 1000;
70}
71
72static int tmp102_read(struct device *dev, enum hwmon_sensor_types type,
73 u32 attr, int channel, long *temp)
74{
75 struct tmp102 *tmp102 = dev_get_drvdata(dev);
76 unsigned int regval;
77 int err, reg;
78
79 switch (attr) {
80 case hwmon_temp_input:
81 /* Is it too early to return a conversion ? */
82 if (time_before(jiffies, tmp102->ready_time)) {
83 dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
84 return -EAGAIN;
85 }
86 reg = TMP102_TEMP_REG;
87 break;
88 case hwmon_temp_max_hyst:
89 reg = TMP102_TLOW_REG;
90 break;
91 case hwmon_temp_max:
92 reg = TMP102_THIGH_REG;
93 break;
94 default:
95 return -EOPNOTSUPP;
96 }
97
98 err = regmap_read(tmp102->regmap, reg, ®val);
99 if (err < 0)
100 return err;
101 *temp = tmp102_reg_to_mC(regval);
102
103 return 0;
104}
105
106static int tmp102_write(struct device *dev, enum hwmon_sensor_types type,
107 u32 attr, int channel, long temp)
108{
109 struct tmp102 *tmp102 = dev_get_drvdata(dev);
110 int reg;
111
112 switch (attr) {
113 case hwmon_temp_max_hyst:
114 reg = TMP102_TLOW_REG;
115 break;
116 case hwmon_temp_max:
117 reg = TMP102_THIGH_REG;
118 break;
119 default:
120 return -EOPNOTSUPP;
121 }
122
123 temp = clamp_val(temp, -256000, 255000);
124 return regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(temp));
125}
126
127static umode_t tmp102_is_visible(const void *data, enum hwmon_sensor_types type,
128 u32 attr, int channel)
129{
130 if (type != hwmon_temp)
131 return 0;
132
133 switch (attr) {
134 case hwmon_temp_input:
135 return 0444;
136 case hwmon_temp_max_hyst:
137 case hwmon_temp_max:
138 return 0644;
139 default:
140 return 0;
141 }
142}
143
144static const struct hwmon_channel_info * const tmp102_info[] = {
145 HWMON_CHANNEL_INFO(chip,
146 HWMON_C_REGISTER_TZ),
147 HWMON_CHANNEL_INFO(temp,
148 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
149 NULL
150};
151
152static const struct hwmon_ops tmp102_hwmon_ops = {
153 .is_visible = tmp102_is_visible,
154 .read = tmp102_read,
155 .write = tmp102_write,
156};
157
158static const struct hwmon_chip_info tmp102_chip_info = {
159 .ops = &tmp102_hwmon_ops,
160 .info = tmp102_info,
161};
162
163static void tmp102_restore_config(void *data)
164{
165 struct tmp102 *tmp102 = data;
166
167 regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig);
168}
169
170static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg)
171{
172 return reg != TMP102_TEMP_REG;
173}
174
175static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg)
176{
177 return reg == TMP102_TEMP_REG;
178}
179
180static const struct regmap_config tmp102_regmap_config = {
181 .reg_bits = 8,
182 .val_bits = 16,
183 .max_register = TMP102_THIGH_REG,
184 .writeable_reg = tmp102_is_writeable_reg,
185 .volatile_reg = tmp102_is_volatile_reg,
186 .val_format_endian = REGMAP_ENDIAN_BIG,
187 .cache_type = REGCACHE_MAPLE,
188 .use_single_read = true,
189 .use_single_write = true,
190};
191
192static int tmp102_probe(struct i2c_client *client)
193{
194 struct device *dev = &client->dev;
195 struct device *hwmon_dev;
196 struct tmp102 *tmp102;
197 unsigned int regval;
198 int err;
199
200 if (!i2c_check_functionality(client->adapter,
201 I2C_FUNC_SMBUS_WORD_DATA)) {
202 dev_err(dev,
203 "adapter doesn't support SMBus word transactions\n");
204 return -ENODEV;
205 }
206
207 tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
208 if (!tmp102)
209 return -ENOMEM;
210
211 i2c_set_clientdata(client, tmp102);
212
213 tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config);
214 if (IS_ERR(tmp102->regmap))
215 return PTR_ERR(tmp102->regmap);
216
217 err = regmap_read(tmp102->regmap, TMP102_CONF_REG, ®val);
218 if (err < 0) {
219 dev_err(dev, "error reading config register\n");
220 return err;
221 }
222
223 if ((regval & ~TMP102_CONFREG_MASK) !=
224 (TMP102_CONF_R0 | TMP102_CONF_R1)) {
225 dev_err(dev, "unexpected config register value\n");
226 return -ENODEV;
227 }
228
229 tmp102->config_orig = regval;
230
231 err = devm_add_action_or_reset(dev, tmp102_restore_config, tmp102);
232 if (err)
233 return err;
234
235 regval &= ~TMP102_CONFIG_CLEAR;
236 regval |= TMP102_CONFIG_SET;
237
238 err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval);
239 if (err < 0) {
240 dev_err(dev, "error writing config register\n");
241 return err;
242 }
243
244 /*
245 * Mark that we are not ready with data until the first
246 * conversion is complete
247 */
248 tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
249
250 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
251 tmp102,
252 &tmp102_chip_info,
253 NULL);
254 if (IS_ERR(hwmon_dev)) {
255 dev_dbg(dev, "unable to register hwmon device\n");
256 return PTR_ERR(hwmon_dev);
257 }
258 dev_info(dev, "initialized\n");
259
260 return 0;
261}
262
263static int tmp102_suspend(struct device *dev)
264{
265 struct i2c_client *client = to_i2c_client(dev);
266 struct tmp102 *tmp102 = i2c_get_clientdata(client);
267
268 return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
269 TMP102_CONF_SD, TMP102_CONF_SD);
270}
271
272static int tmp102_resume(struct device *dev)
273{
274 struct i2c_client *client = to_i2c_client(dev);
275 struct tmp102 *tmp102 = i2c_get_clientdata(client);
276 int err;
277
278 err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
279 TMP102_CONF_SD, 0);
280
281 tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
282
283 return err;
284}
285
286static DEFINE_SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
287
288static const struct i2c_device_id tmp102_id[] = {
289 { "tmp102" },
290 { }
291};
292MODULE_DEVICE_TABLE(i2c, tmp102_id);
293
294static const struct of_device_id __maybe_unused tmp102_of_match[] = {
295 { .compatible = "ti,tmp102" },
296 { },
297};
298MODULE_DEVICE_TABLE(of, tmp102_of_match);
299
300static struct i2c_driver tmp102_driver = {
301 .driver.name = DRIVER_NAME,
302 .driver.of_match_table = of_match_ptr(tmp102_of_match),
303 .driver.pm = pm_sleep_ptr(&tmp102_dev_pm_ops),
304 .probe = tmp102_probe,
305 .id_table = tmp102_id,
306};
307
308module_i2c_driver(tmp102_driver);
309
310MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
311MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
312MODULE_LICENSE("GPL");