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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
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};
62
63
64static inline int tmp102_reg_to_mC(s16 val)
65{
66 return ((val & ~0x01) * 1000) / 128;
67}
68
69
70static inline u16 tmp102_mC_to_reg(int val)
71{
72 return (val * 128) / 1000;
73}
74
75static const u8 tmp102_reg[] = {
76 TMP102_TEMP_REG,
77 TMP102_TLOW_REG,
78 TMP102_THIGH_REG,
79};
80
81static struct tmp102 *tmp102_update_device(struct device *dev)
82{
83 struct tmp102 *tmp102 = dev_get_drvdata(dev);
84 struct i2c_client *client = tmp102->client;
85
86 mutex_lock(&tmp102->lock);
87 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
88 int i;
89 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
90 int status = i2c_smbus_read_word_swapped(client,
91 tmp102_reg[i]);
92 if (status > -1)
93 tmp102->temp[i] = tmp102_reg_to_mC(status);
94 }
95 tmp102->last_update = jiffies;
96 }
97 mutex_unlock(&tmp102->lock);
98 return tmp102;
99}
100
101static int tmp102_read_temp(void *dev, long *temp)
102{
103 struct tmp102 *tmp102 = tmp102_update_device(dev);
104
105 *temp = tmp102->temp[0];
106
107 return 0;
108}
109
110static ssize_t tmp102_show_temp(struct device *dev,
111 struct device_attribute *attr,
112 char *buf)
113{
114 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
115 struct tmp102 *tmp102 = tmp102_update_device(dev);
116
117 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
118}
119
120static ssize_t tmp102_set_temp(struct device *dev,
121 struct device_attribute *attr,
122 const char *buf, size_t count)
123{
124 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
125 struct tmp102 *tmp102 = dev_get_drvdata(dev);
126 struct i2c_client *client = tmp102->client;
127 long val;
128 int status;
129
130 if (kstrtol(buf, 10, &val) < 0)
131 return -EINVAL;
132 val = clamp_val(val, -256000, 255000);
133
134 mutex_lock(&tmp102->lock);
135 tmp102->temp[sda->index] = val;
136 status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
137 tmp102_mC_to_reg(val));
138 mutex_unlock(&tmp102->lock);
139 return status ? : count;
140}
141
142static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
143
144static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
145 tmp102_set_temp, 1);
146
147static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
148 tmp102_set_temp, 2);
149
150static struct attribute *tmp102_attrs[] = {
151 &sensor_dev_attr_temp1_input.dev_attr.attr,
152 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
153 &sensor_dev_attr_temp1_max.dev_attr.attr,
154 NULL
155};
156ATTRIBUTE_GROUPS(tmp102);
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 tmp102_probe(struct i2c_client *client,
162 const struct i2c_device_id *id)
163{
164 struct device *dev = &client->dev;
165 struct device *hwmon_dev;
166 struct tmp102 *tmp102;
167 int status;
168
169 if (!i2c_check_functionality(client->adapter,
170 I2C_FUNC_SMBUS_WORD_DATA)) {
171 dev_err(dev,
172 "adapter doesn't support SMBus word transactions\n");
173 return -ENODEV;
174 }
175
176 tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
177 if (!tmp102)
178 return -ENOMEM;
179
180 i2c_set_clientdata(client, tmp102);
181 tmp102->client = client;
182
183 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
184 if (status < 0) {
185 dev_err(dev, "error reading config register\n");
186 return status;
187 }
188 tmp102->config_orig = status;
189 status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
190 TMP102_CONFIG);
191 if (status < 0) {
192 dev_err(dev, "error writing config register\n");
193 goto fail_restore_config;
194 }
195 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
196 if (status < 0) {
197 dev_err(dev, "error reading config register\n");
198 goto fail_restore_config;
199 }
200 status &= ~TMP102_CONFIG_RD_ONLY;
201 if (status != TMP102_CONFIG) {
202 dev_err(dev, "config settings did not stick\n");
203 status = -ENODEV;
204 goto fail_restore_config;
205 }
206 tmp102->last_update = jiffies - HZ;
207 mutex_init(&tmp102->lock);
208
209 hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
210 tmp102, tmp102_groups);
211 if (IS_ERR(hwmon_dev)) {
212 dev_dbg(dev, "unable to register hwmon device\n");
213 status = PTR_ERR(hwmon_dev);
214 goto fail_restore_config;
215 }
216 tmp102->hwmon_dev = hwmon_dev;
217 tmp102->tz = thermal_zone_of_sensor_register(hwmon_dev, 0, hwmon_dev,
218 tmp102_read_temp, NULL);
219 if (IS_ERR(tmp102->tz))
220 tmp102->tz = NULL;
221
222 dev_info(dev, "initialized\n");
223
224 return 0;
225
226fail_restore_config:
227 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
228 tmp102->config_orig);
229 return status;
230}
231
232static int tmp102_remove(struct i2c_client *client)
233{
234 struct tmp102 *tmp102 = i2c_get_clientdata(client);
235
236 thermal_zone_of_sensor_unregister(tmp102->hwmon_dev, tmp102->tz);
237 hwmon_device_unregister(tmp102->hwmon_dev);
238
239
240 if (tmp102->config_orig & TMP102_CONF_SD) {
241 int config;
242
243 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
244 if (config >= 0)
245 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
246 config | TMP102_CONF_SD);
247 }
248
249 return 0;
250}
251
252#ifdef CONFIG_PM
253static int tmp102_suspend(struct device *dev)
254{
255 struct i2c_client *client = to_i2c_client(dev);
256 int config;
257
258 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
259 if (config < 0)
260 return config;
261
262 config |= TMP102_CONF_SD;
263 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
264}
265
266static int tmp102_resume(struct device *dev)
267{
268 struct i2c_client *client = to_i2c_client(dev);
269 int config;
270
271 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
272 if (config < 0)
273 return config;
274
275 config &= ~TMP102_CONF_SD;
276 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
277}
278
279static const struct dev_pm_ops tmp102_dev_pm_ops = {
280 .suspend = tmp102_suspend,
281 .resume = tmp102_resume,
282};
283
284#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
285#else
286#define TMP102_DEV_PM_OPS NULL
287#endif
288
289static const struct i2c_device_id tmp102_id[] = {
290 { "tmp102", 0 },
291 { }
292};
293MODULE_DEVICE_TABLE(i2c, tmp102_id);
294
295static struct i2c_driver tmp102_driver = {
296 .driver.name = DRIVER_NAME,
297 .driver.pm = TMP102_DEV_PM_OPS,
298 .probe = tmp102_probe,
299 .remove = tmp102_remove,
300 .id_table = tmp102_id,
301};
302
303module_i2c_driver(tmp102_driver);
304
305MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
306MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
307MODULE_LICENSE("GPL");
308
