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21#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/slab.h>
24#include <linux/jiffies.h>
25#include <linux/i2c.h>
26#include <linux/hwmon.h>
27#include <linux/hwmon-sysfs.h>
28#include <linux/err.h>
29#include <linux/mutex.h>
30#include "lm75.h"
31
32
33
34
35
36
37enum lm75_type {
38 ds1775,
39 ds75,
40 lm75,
41 lm75a,
42 max6625,
43 max6626,
44 mcp980x,
45 stds75,
46 tcn75,
47 tmp100,
48 tmp101,
49 tmp105,
50 tmp175,
51 tmp275,
52 tmp75,
53};
54
55
56static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
57 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
58
59
60
61#define LM75_REG_CONF 0x01
62static const u8 LM75_REG_TEMP[3] = {
63 0x00,
64 0x03,
65 0x02,
66};
67
68
69struct lm75_data {
70 struct device *hwmon_dev;
71 struct mutex update_lock;
72 u8 orig_conf;
73 char valid;
74 unsigned long last_updated;
75 u16 temp[3];
76
77
78
79};
80
81static int lm75_read_value(struct i2c_client *client, u8 reg);
82static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
83static struct lm75_data *lm75_update_device(struct device *dev);
84
85
86
87
88
89
90static ssize_t show_temp(struct device *dev, struct device_attribute *da,
91 char *buf)
92{
93 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
94 struct lm75_data *data = lm75_update_device(dev);
95 return sprintf(buf, "%d\n",
96 LM75_TEMP_FROM_REG(data->temp[attr->index]));
97}
98
99static ssize_t set_temp(struct device *dev, struct device_attribute *da,
100 const char *buf, size_t count)
101{
102 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
103 struct i2c_client *client = to_i2c_client(dev);
104 struct lm75_data *data = i2c_get_clientdata(client);
105 int nr = attr->index;
106 long temp;
107 int error;
108
109 error = strict_strtol(buf, 10, &temp);
110 if (error)
111 return error;
112
113 mutex_lock(&data->update_lock);
114 data->temp[nr] = LM75_TEMP_TO_REG(temp);
115 lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
116 mutex_unlock(&data->update_lock);
117 return count;
118}
119
120static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
121 show_temp, set_temp, 1);
122static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
123 show_temp, set_temp, 2);
124static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
125
126static struct attribute *lm75_attributes[] = {
127 &sensor_dev_attr_temp1_input.dev_attr.attr,
128 &sensor_dev_attr_temp1_max.dev_attr.attr,
129 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
130
131 NULL
132};
133
134static const struct attribute_group lm75_group = {
135 .attrs = lm75_attributes,
136};
137
138
139
140
141
142static int
143lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
144{
145 struct lm75_data *data;
146 int status;
147 u8 set_mask, clr_mask;
148 int new;
149
150 if (!i2c_check_functionality(client->adapter,
151 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
152 return -EIO;
153
154 data = kzalloc(sizeof(struct lm75_data), GFP_KERNEL);
155 if (!data)
156 return -ENOMEM;
157
158 i2c_set_clientdata(client, data);
159 mutex_init(&data->update_lock);
160
161
162
163
164 set_mask = 0;
165 clr_mask = (1 << 0)
166 | (1 << 6) | (1 << 5);
167
168
169 status = lm75_read_value(client, LM75_REG_CONF);
170 if (status < 0) {
171 dev_dbg(&client->dev, "Can't read config? %d\n", status);
172 goto exit_free;
173 }
174 data->orig_conf = status;
175 new = status & ~clr_mask;
176 new |= set_mask;
177 if (status != new)
178 lm75_write_value(client, LM75_REG_CONF, new);
179 dev_dbg(&client->dev, "Config %02x\n", new);
180
181
182 status = sysfs_create_group(&client->dev.kobj, &lm75_group);
183 if (status)
184 goto exit_free;
185
186 data->hwmon_dev = hwmon_device_register(&client->dev);
187 if (IS_ERR(data->hwmon_dev)) {
188 status = PTR_ERR(data->hwmon_dev);
189 goto exit_remove;
190 }
191
192 dev_info(&client->dev, "%s: sensor '%s'\n",
193 dev_name(data->hwmon_dev), client->name);
194
195 return 0;
196
197exit_remove:
198 sysfs_remove_group(&client->dev.kobj, &lm75_group);
199exit_free:
200 kfree(data);
201 return status;
202}
203
204static int lm75_remove(struct i2c_client *client)
205{
206 struct lm75_data *data = i2c_get_clientdata(client);
207
208 hwmon_device_unregister(data->hwmon_dev);
209 sysfs_remove_group(&client->dev.kobj, &lm75_group);
210 lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
211 kfree(data);
212 return 0;
213}
214
215static const struct i2c_device_id lm75_ids[] = {
216 { "ds1775", ds1775, },
217 { "ds75", ds75, },
218 { "lm75", lm75, },
219 { "lm75a", lm75a, },
220 { "max6625", max6625, },
221 { "max6626", max6626, },
222 { "mcp980x", mcp980x, },
223 { "stds75", stds75, },
224 { "tcn75", tcn75, },
225 { "tmp100", tmp100, },
226 { "tmp101", tmp101, },
227 { "tmp105", tmp105, },
228 { "tmp175", tmp175, },
229 { "tmp275", tmp275, },
230 { "tmp75", tmp75, },
231 { }
232};
233MODULE_DEVICE_TABLE(i2c, lm75_ids);
234
235
236static int lm75_detect(struct i2c_client *new_client,
237 struct i2c_board_info *info)
238{
239 struct i2c_adapter *adapter = new_client->adapter;
240 int i;
241 int cur, conf, hyst, os;
242
243 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
244 I2C_FUNC_SMBUS_WORD_DATA))
245 return -ENODEV;
246
247
248
249
250
251
252
253
254
255
256 cur = i2c_smbus_read_word_data(new_client, 0);
257 conf = i2c_smbus_read_byte_data(new_client, 1);
258 hyst = i2c_smbus_read_word_data(new_client, 2);
259 if (i2c_smbus_read_word_data(new_client, 4) != hyst
260 || i2c_smbus_read_word_data(new_client, 5) != hyst
261 || i2c_smbus_read_word_data(new_client, 6) != hyst
262 || i2c_smbus_read_word_data(new_client, 7) != hyst)
263 return -ENODEV;
264 os = i2c_smbus_read_word_data(new_client, 3);
265 if (i2c_smbus_read_word_data(new_client, 4) != os
266 || i2c_smbus_read_word_data(new_client, 5) != os
267 || i2c_smbus_read_word_data(new_client, 6) != os
268 || i2c_smbus_read_word_data(new_client, 7) != os)
269 return -ENODEV;
270
271
272 if (conf & 0xe0)
273 return -ENODEV;
274
275
276 for (i = 8; i < 0xff; i += 8) {
277 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
278 || i2c_smbus_read_word_data(new_client, i + 2) != hyst
279 || i2c_smbus_read_word_data(new_client, i + 3) != os)
280 return -ENODEV;
281 }
282
283 strlcpy(info->type, "lm75", I2C_NAME_SIZE);
284
285 return 0;
286}
287
288#ifdef CONFIG_PM
289static int lm75_suspend(struct device *dev)
290{
291 int status;
292 struct i2c_client *client = to_i2c_client(dev);
293 status = lm75_read_value(client, LM75_REG_CONF);
294 if (status < 0) {
295 dev_dbg(&client->dev, "Can't read config? %d\n", status);
296 return status;
297 }
298 status = status | LM75_SHUTDOWN;
299 lm75_write_value(client, LM75_REG_CONF, status);
300 return 0;
301}
302
303static int lm75_resume(struct device *dev)
304{
305 int status;
306 struct i2c_client *client = to_i2c_client(dev);
307 status = lm75_read_value(client, LM75_REG_CONF);
308 if (status < 0) {
309 dev_dbg(&client->dev, "Can't read config? %d\n", status);
310 return status;
311 }
312 status = status & ~LM75_SHUTDOWN;
313 lm75_write_value(client, LM75_REG_CONF, status);
314 return 0;
315}
316
317static const struct dev_pm_ops lm75_dev_pm_ops = {
318 .suspend = lm75_suspend,
319 .resume = lm75_resume,
320};
321#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
322#else
323#define LM75_DEV_PM_OPS NULL
324#endif
325
326static struct i2c_driver lm75_driver = {
327 .class = I2C_CLASS_HWMON,
328 .driver = {
329 .name = "lm75",
330 .pm = LM75_DEV_PM_OPS,
331 },
332 .probe = lm75_probe,
333 .remove = lm75_remove,
334 .id_table = lm75_ids,
335 .detect = lm75_detect,
336 .address_list = normal_i2c,
337};
338
339
340
341
342
343
344
345
346
347
348static int lm75_read_value(struct i2c_client *client, u8 reg)
349{
350 int value;
351
352 if (reg == LM75_REG_CONF)
353 return i2c_smbus_read_byte_data(client, reg);
354
355 value = i2c_smbus_read_word_data(client, reg);
356 return (value < 0) ? value : swab16(value);
357}
358
359static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
360{
361 if (reg == LM75_REG_CONF)
362 return i2c_smbus_write_byte_data(client, reg, value);
363 else
364 return i2c_smbus_write_word_data(client, reg, swab16(value));
365}
366
367static struct lm75_data *lm75_update_device(struct device *dev)
368{
369 struct i2c_client *client = to_i2c_client(dev);
370 struct lm75_data *data = i2c_get_clientdata(client);
371
372 mutex_lock(&data->update_lock);
373
374 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
375 || !data->valid) {
376 int i;
377 dev_dbg(&client->dev, "Starting lm75 update\n");
378
379 for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
380 int status;
381
382 status = lm75_read_value(client, LM75_REG_TEMP[i]);
383 if (status < 0)
384 dev_dbg(&client->dev, "reg %d, err %d\n",
385 LM75_REG_TEMP[i], status);
386 else
387 data->temp[i] = status;
388 }
389 data->last_updated = jiffies;
390 data->valid = 1;
391 }
392
393 mutex_unlock(&data->update_lock);
394
395 return data;
396}
397
398
399
400
401
402static int __init sensors_lm75_init(void)
403{
404 return i2c_add_driver(&lm75_driver);
405}
406
407static void __exit sensors_lm75_exit(void)
408{
409 i2c_del_driver(&lm75_driver);
410}
411
412MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
413MODULE_DESCRIPTION("LM75 driver");
414MODULE_LICENSE("GPL");
415
416module_init(sensors_lm75_init);
417module_exit(sensors_lm75_exit);
418