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cff37c9e | 1 | /* Texas Instruments TMP102 SMBus temperature sensor driver |
beb1b6bb | 2 | * |
cff37c9e | 3 | * Copyright (C) 2010 Steven King <sfking@fdwdc.com> |
beb1b6bb SK |
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 | ||
beb1b6bb SK |
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> | |
cff37c9e | 28 | #include <linux/device.h> |
beb1b6bb SK |
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 | ||
50 | struct tmp102 { | |
51 | struct device *hwmon_dev; | |
52 | struct mutex lock; | |
38806bda | 53 | u16 config_orig; |
beb1b6bb SK |
54 | unsigned long last_update; |
55 | int temp[3]; | |
56 | }; | |
57 | ||
cff37c9e JD |
58 | /* SMBus specifies low byte first, but the TMP102 returns high byte first, |
59 | * so we have to swab16 the values */ | |
60 | static inline int tmp102_read_reg(struct i2c_client *client, u8 reg) | |
beb1b6bb SK |
61 | { |
62 | int result = i2c_smbus_read_word_data(client, reg); | |
63 | return result < 0 ? result : swab16(result); | |
64 | } | |
65 | ||
cff37c9e | 66 | static inline int tmp102_write_reg(struct i2c_client *client, u8 reg, u16 val) |
beb1b6bb SK |
67 | { |
68 | return i2c_smbus_write_word_data(client, reg, swab16(val)); | |
69 | } | |
70 | ||
cff37c9e JD |
71 | /* convert left adjusted 13-bit TMP102 register value to milliCelsius */ |
72 | static inline int tmp102_reg_to_mC(s16 val) | |
beb1b6bb | 73 | { |
cff37c9e | 74 | return ((val & ~0x01) * 1000) / 128; |
beb1b6bb SK |
75 | } |
76 | ||
cff37c9e JD |
77 | /* convert milliCelsius to left adjusted 13-bit TMP102 register value */ |
78 | static inline u16 tmp102_mC_to_reg(int val) | |
beb1b6bb SK |
79 | { |
80 | return (val * 128) / 1000; | |
81 | } | |
82 | ||
83 | static const u8 tmp102_reg[] = { | |
84 | TMP102_TEMP_REG, | |
85 | TMP102_TLOW_REG, | |
86 | TMP102_THIGH_REG, | |
87 | }; | |
88 | ||
89 | static struct tmp102 *tmp102_update_device(struct i2c_client *client) | |
90 | { | |
91 | struct tmp102 *tmp102 = i2c_get_clientdata(client); | |
92 | ||
93 | mutex_lock(&tmp102->lock); | |
cff37c9e | 94 | if (time_after(jiffies, tmp102->last_update + HZ / 3)) { |
beb1b6bb SK |
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 | ||
107 | static 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 | ||
117 | static 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; | |
cff37c9e | 125 | int status; |
beb1b6bb | 126 | |
cff37c9e | 127 | if (strict_strtol(buf, 10, &val) < 0) |
beb1b6bb | 128 | return -EINVAL; |
cff37c9e JD |
129 | val = SENSORS_LIMIT(val, -256000, 255000); |
130 | ||
beb1b6bb | 131 | mutex_lock(&tmp102->lock); |
cff37c9e JD |
132 | tmp102->temp[sda->index] = val; |
133 | status = tmp102_write_reg(client, tmp102_reg[sda->index], | |
134 | tmp102_mC_to_reg(val)); | |
beb1b6bb SK |
135 | mutex_unlock(&tmp102->lock); |
136 | return status ? : count; | |
137 | } | |
138 | ||
139 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0); | |
140 | ||
141 | static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp, | |
142 | tmp102_set_temp, 1); | |
143 | ||
144 | static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp, | |
145 | tmp102_set_temp, 2); | |
146 | ||
147 | static 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 | ||
154 | static 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 | ||
161 | static int __devinit tmp102_probe(struct i2c_client *client, | |
162 | const struct i2c_device_id *id) | |
163 | { | |
164 | struct tmp102 *tmp102; | |
165 | int status; | |
166 | ||
cff37c9e | 167 | if (!i2c_check_functionality(client->adapter, |
beb1b6bb | 168 | I2C_FUNC_SMBUS_WORD_DATA)) { |
25985edc | 169 | dev_err(&client->dev, "adapter doesn't support SMBus word " |
cff37c9e | 170 | "transactions\n"); |
beb1b6bb SK |
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 | ||
38806bda JD |
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; | |
cff37c9e JD |
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"); | |
38806bda | 190 | goto fail_restore_config; |
cff37c9e | 191 | } |
beb1b6bb SK |
192 | status = tmp102_read_reg(client, TMP102_CONF_REG); |
193 | if (status < 0) { | |
cff37c9e | 194 | dev_err(&client->dev, "error reading config register\n"); |
38806bda | 195 | goto fail_restore_config; |
beb1b6bb SK |
196 | } |
197 | status &= ~TMP102_CONFIG_RD_ONLY; | |
198 | if (status != TMP102_CONFIG) { | |
cff37c9e JD |
199 | dev_err(&client->dev, "config settings did not stick\n"); |
200 | status = -ENODEV; | |
38806bda | 201 | goto fail_restore_config; |
beb1b6bb SK |
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"); | |
38806bda | 209 | goto fail_restore_config; |
beb1b6bb SK |
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); | |
38806bda | 215 | goto fail_remove_sysfs; |
beb1b6bb SK |
216 | } |
217 | ||
218 | dev_info(&client->dev, "initialized\n"); | |
219 | ||
220 | return 0; | |
38806bda JD |
221 | |
222 | fail_remove_sysfs: | |
beb1b6bb | 223 | sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group); |
38806bda JD |
224 | fail_restore_config: |
225 | tmp102_write_reg(client, TMP102_CONF_REG, tmp102->config_orig); | |
226 | fail_free: | |
beb1b6bb SK |
227 | kfree(tmp102); |
228 | ||
cff37c9e | 229 | return status; |
beb1b6bb SK |
230 | } |
231 | ||
232 | static int __devexit tmp102_remove(struct i2c_client *client) | |
233 | { | |
234 | struct tmp102 *tmp102 = i2c_get_clientdata(client); | |
235 | ||
beb1b6bb SK |
236 | hwmon_device_unregister(tmp102->hwmon_dev); |
237 | sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group); | |
38806bda JD |
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 | ||
beb1b6bb SK |
249 | kfree(tmp102); |
250 | ||
251 | return 0; | |
252 | } | |
253 | ||
254 | #ifdef CONFIG_PM | |
255 | static int tmp102_suspend(struct device *dev) | |
256 | { | |
257 | struct i2c_client *client = to_i2c_client(dev); | |
8d4dee98 | 258 | int config; |
beb1b6bb | 259 | |
8d4dee98 JD |
260 | config = tmp102_read_reg(client, TMP102_CONF_REG); |
261 | if (config < 0) | |
262 | return config; | |
beb1b6bb | 263 | |
8d4dee98 JD |
264 | config |= TMP102_CONF_SD; |
265 | return tmp102_write_reg(client, TMP102_CONF_REG, config); | |
beb1b6bb SK |
266 | } |
267 | ||
268 | static int tmp102_resume(struct device *dev) | |
269 | { | |
270 | struct i2c_client *client = to_i2c_client(dev); | |
8d4dee98 | 271 | int config; |
beb1b6bb | 272 | |
8d4dee98 JD |
273 | config = tmp102_read_reg(client, TMP102_CONF_REG); |
274 | if (config < 0) | |
275 | return config; | |
beb1b6bb | 276 | |
8d4dee98 JD |
277 | config &= ~TMP102_CONF_SD; |
278 | return tmp102_write_reg(client, TMP102_CONF_REG, config); | |
beb1b6bb SK |
279 | } |
280 | ||
281 | static 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 | ||
beb1b6bb | 291 | static const struct i2c_device_id tmp102_id[] = { |
cff37c9e | 292 | { "tmp102", 0 }, |
beb1b6bb SK |
293 | { } |
294 | }; | |
cff37c9e | 295 | MODULE_DEVICE_TABLE(i2c, tmp102_id); |
beb1b6bb SK |
296 | |
297 | static struct i2c_driver tmp102_driver = { | |
298 | .driver.name = DRIVER_NAME, | |
299 | .driver.pm = TMP102_DEV_PM_OPS, | |
beb1b6bb SK |
300 | .probe = tmp102_probe, |
301 | .remove = __devexit_p(tmp102_remove), | |
302 | .id_table = tmp102_id, | |
beb1b6bb SK |
303 | }; |
304 | ||
305 | static int __init tmp102_init(void) | |
306 | { | |
307 | return i2c_add_driver(&tmp102_driver); | |
308 | } | |
309 | module_init(tmp102_init); | |
310 | ||
311 | static void __exit tmp102_exit(void) | |
312 | { | |
313 | i2c_del_driver(&tmp102_driver); | |
314 | } | |
315 | module_exit(tmp102_exit); | |
316 | ||
beb1b6bb SK |
317 | MODULE_AUTHOR("Steven King <sfking@fdwdc.com>"); |
318 | MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver"); | |
319 | MODULE_LICENSE("GPL"); |