xref: /openbmc/linux/drivers/hwmon/adt7410.c (revision c55dc91e)
1 /*
2  * adt7410.c - Part of lm_sensors, Linux kernel modules for hardware
3  *	 monitoring
4  * This driver handles the ADT7410 and compatible digital temperature sensors.
5  * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
6  * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
7  * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/jiffies.h>
28 #include <linux/i2c.h>
29 #include <linux/hwmon.h>
30 #include <linux/hwmon-sysfs.h>
31 #include <linux/err.h>
32 #include <linux/mutex.h>
33 #include <linux/delay.h>
34 
35 /*
36  * ADT7410 registers definition
37  */
38 
39 #define ADT7410_TEMPERATURE		0
40 #define ADT7410_STATUS			2
41 #define ADT7410_CONFIG			3
42 #define ADT7410_T_ALARM_HIGH		4
43 #define ADT7410_T_ALARM_LOW		6
44 #define ADT7410_T_CRIT			8
45 #define ADT7410_T_HYST			0xA
46 
47 /*
48  * ADT7410 status
49  */
50 #define ADT7410_STAT_T_LOW		(1 << 4)
51 #define ADT7410_STAT_T_HIGH		(1 << 5)
52 #define ADT7410_STAT_T_CRIT		(1 << 6)
53 #define ADT7410_STAT_NOT_RDY		(1 << 7)
54 
55 /*
56  * ADT7410 config
57  */
58 #define ADT7410_FAULT_QUEUE_MASK	(1 << 0 | 1 << 1)
59 #define ADT7410_CT_POLARITY		(1 << 2)
60 #define ADT7410_INT_POLARITY		(1 << 3)
61 #define ADT7410_EVENT_MODE		(1 << 4)
62 #define ADT7410_MODE_MASK		(1 << 5 | 1 << 6)
63 #define ADT7410_FULL			(0 << 5 | 0 << 6)
64 #define ADT7410_PD			(1 << 5 | 1 << 6)
65 #define ADT7410_RESOLUTION		(1 << 7)
66 
67 /*
68  * ADT7410 masks
69  */
70 #define ADT7410_T13_VALUE_MASK			0xFFF8
71 #define ADT7410_T_HYST_MASK			0xF
72 
73 /* straight from the datasheet */
74 #define ADT7410_TEMP_MIN (-55000)
75 #define ADT7410_TEMP_MAX 150000
76 
77 enum adt7410_type {		/* keep sorted in alphabetical order */
78 	adt7410,
79 };
80 
81 static const u8 ADT7410_REG_TEMP[4] = {
82 	ADT7410_TEMPERATURE,		/* input */
83 	ADT7410_T_ALARM_HIGH,		/* high */
84 	ADT7410_T_ALARM_LOW,		/* low */
85 	ADT7410_T_CRIT,			/* critical */
86 };
87 
88 /* Each client has this additional data */
89 struct adt7410_data {
90 	struct device		*hwmon_dev;
91 	struct mutex		update_lock;
92 	u8			config;
93 	u8			oldconfig;
94 	bool			valid;		/* true if registers valid */
95 	unsigned long		last_updated;	/* In jiffies */
96 	s16			temp[4];	/* Register values,
97 						   0 = input
98 						   1 = high
99 						   2 = low
100 						   3 = critical */
101 	u8			hyst;		/* hysteresis offset */
102 };
103 
104 /*
105  * adt7410 register access by I2C
106  */
107 static int adt7410_temp_ready(struct i2c_client *client)
108 {
109 	int i, status;
110 
111 	for (i = 0; i < 6; i++) {
112 		status = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
113 		if (status < 0)
114 			return status;
115 		if (!(status & ADT7410_STAT_NOT_RDY))
116 			return 0;
117 		msleep(60);
118 	}
119 	return -ETIMEDOUT;
120 }
121 
122 static int adt7410_update_temp(struct device *dev)
123 {
124 	struct i2c_client *client = to_i2c_client(dev);
125 	struct adt7410_data *data = i2c_get_clientdata(client);
126 	int ret = 0;
127 
128 	mutex_lock(&data->update_lock);
129 
130 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
131 	    || !data->valid) {
132 		int temp;
133 
134 		dev_dbg(&client->dev, "Starting update\n");
135 
136 		ret = adt7410_temp_ready(client); /* check for new value */
137 		if (ret)
138 			goto abort;
139 
140 		temp = i2c_smbus_read_word_swapped(client, ADT7410_REG_TEMP[0]);
141 		if (temp < 0) {
142 			ret = temp;
143 			dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
144 				ADT7410_REG_TEMP[0], ret);
145 			goto abort;
146 		}
147 		data->temp[0] = temp;
148 
149 		data->last_updated = jiffies;
150 		data->valid = true;
151 	}
152 
153 abort:
154 	mutex_unlock(&data->update_lock);
155 	return ret;
156 }
157 
158 static int adt7410_fill_cache(struct i2c_client *client)
159 {
160 	struct adt7410_data *data = i2c_get_clientdata(client);
161 	int ret;
162 	int i;
163 
164 	for (i = 1; i < ARRAY_SIZE(ADT7410_REG_TEMP); i++) {
165 		ret = i2c_smbus_read_word_swapped(client, ADT7410_REG_TEMP[i]);
166 		if (ret < 0) {
167 			dev_dbg(&client->dev,
168 				"Failed to read value: reg %d, error %d\n",
169 				ADT7410_REG_TEMP[i], ret);
170 			return ret;
171 		}
172 		data->temp[i] = ret;
173 	}
174 
175 	ret = i2c_smbus_read_byte_data(client, ADT7410_T_HYST);
176 	if (ret < 0) {
177 		dev_dbg(&client->dev,
178 			"Failed to read value: hyst reg, error %d\n",
179 			ret);
180 		return ret;
181 	}
182 	data->hyst = ret;
183 
184 	return 0;
185 }
186 
187 static s16 ADT7410_TEMP_TO_REG(long temp)
188 {
189 	return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7410_TEMP_MIN,
190 					   ADT7410_TEMP_MAX) * 128, 1000);
191 }
192 
193 static int ADT7410_REG_TO_TEMP(struct adt7410_data *data, s16 reg)
194 {
195 	/* in 13 bit mode, bits 0-2 are status flags - mask them out */
196 	if (!(data->config & ADT7410_RESOLUTION))
197 		reg &= ADT7410_T13_VALUE_MASK;
198 	/*
199 	 * temperature is stored in twos complement format, in steps of
200 	 * 1/128°C
201 	 */
202 	return DIV_ROUND_CLOSEST(reg * 1000, 128);
203 }
204 
205 /*-----------------------------------------------------------------------*/
206 
207 /* sysfs attributes for hwmon */
208 
209 static ssize_t adt7410_show_temp(struct device *dev,
210 				 struct device_attribute *da, char *buf)
211 {
212 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
213 	struct i2c_client *client = to_i2c_client(dev);
214 	struct adt7410_data *data = i2c_get_clientdata(client);
215 
216 	if (attr->index == 0) {
217 		int ret;
218 
219 		ret = adt7410_update_temp(dev);
220 		if (ret)
221 			return ret;
222 	}
223 
224 	return sprintf(buf, "%d\n", ADT7410_REG_TO_TEMP(data,
225 		       data->temp[attr->index]));
226 }
227 
228 static ssize_t adt7410_set_temp(struct device *dev,
229 				struct device_attribute *da,
230 				const char *buf, size_t count)
231 {
232 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
233 	struct i2c_client *client = to_i2c_client(dev);
234 	struct adt7410_data *data = i2c_get_clientdata(client);
235 	int nr = attr->index;
236 	long temp;
237 	int ret;
238 
239 	ret = kstrtol(buf, 10, &temp);
240 	if (ret)
241 		return ret;
242 
243 	mutex_lock(&data->update_lock);
244 	data->temp[nr] = ADT7410_TEMP_TO_REG(temp);
245 	ret = i2c_smbus_write_word_swapped(client, ADT7410_REG_TEMP[nr],
246 					   data->temp[nr]);
247 	if (ret)
248 		count = ret;
249 	mutex_unlock(&data->update_lock);
250 	return count;
251 }
252 
253 static ssize_t adt7410_show_t_hyst(struct device *dev,
254 				   struct device_attribute *da,
255 				   char *buf)
256 {
257 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
258 	struct i2c_client *client = to_i2c_client(dev);
259 	struct adt7410_data *data = i2c_get_clientdata(client);
260 	int nr = attr->index;
261 	int hyst;
262 
263 	hyst = (data->hyst & ADT7410_T_HYST_MASK) * 1000;
264 
265 	/*
266 	 * hysteresis is stored as a 4 bit offset in the device, convert it
267 	 * to an absolute value
268 	 */
269 	if (nr == 2)	/* min has positive offset, others have negative */
270 		hyst = -hyst;
271 	return sprintf(buf, "%d\n",
272 		       ADT7410_REG_TO_TEMP(data, data->temp[nr]) - hyst);
273 }
274 
275 static ssize_t adt7410_set_t_hyst(struct device *dev,
276 				  struct device_attribute *da,
277 				  const char *buf, size_t count)
278 {
279 	struct i2c_client *client = to_i2c_client(dev);
280 	struct adt7410_data *data = i2c_get_clientdata(client);
281 	int limit, ret;
282 	long hyst;
283 
284 	ret = kstrtol(buf, 10, &hyst);
285 	if (ret)
286 		return ret;
287 	/* convert absolute hysteresis value to a 4 bit delta value */
288 	limit = ADT7410_REG_TO_TEMP(data, data->temp[1]);
289 	hyst = clamp_val(hyst, ADT7410_TEMP_MIN, ADT7410_TEMP_MAX);
290 	data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
291 			       ADT7410_T_HYST_MASK);
292 	ret = i2c_smbus_write_byte_data(client, ADT7410_T_HYST, data->hyst);
293 	if (ret)
294 		return ret;
295 
296 	return count;
297 }
298 
299 static ssize_t adt7410_show_alarm(struct device *dev,
300 				  struct device_attribute *da,
301 				  char *buf)
302 {
303 	struct i2c_client *client = to_i2c_client(dev);
304 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
305 	int ret;
306 
307 	ret = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
308 	if (ret < 0)
309 		return ret;
310 
311 	return sprintf(buf, "%d\n", !!(ret & attr->index));
312 }
313 
314 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7410_show_temp, NULL, 0);
315 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
316 			  adt7410_show_temp, adt7410_set_temp, 1);
317 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
318 			  adt7410_show_temp, adt7410_set_temp, 2);
319 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
320 			  adt7410_show_temp, adt7410_set_temp, 3);
321 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
322 			  adt7410_show_t_hyst, adt7410_set_t_hyst, 1);
323 static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
324 			  adt7410_show_t_hyst, NULL, 2);
325 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
326 			  adt7410_show_t_hyst, NULL, 3);
327 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7410_show_alarm,
328 			  NULL, ADT7410_STAT_T_LOW);
329 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7410_show_alarm,
330 			  NULL, ADT7410_STAT_T_HIGH);
331 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7410_show_alarm,
332 			  NULL, ADT7410_STAT_T_CRIT);
333 
334 static struct attribute *adt7410_attributes[] = {
335 	&sensor_dev_attr_temp1_input.dev_attr.attr,
336 	&sensor_dev_attr_temp1_max.dev_attr.attr,
337 	&sensor_dev_attr_temp1_min.dev_attr.attr,
338 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
339 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
340 	&sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
341 	&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
342 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
343 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
344 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
345 	NULL
346 };
347 
348 static const struct attribute_group adt7410_group = {
349 	.attrs = adt7410_attributes,
350 };
351 
352 /*-----------------------------------------------------------------------*/
353 
354 /* device probe and removal */
355 
356 static int adt7410_probe(struct i2c_client *client,
357 			 const struct i2c_device_id *id)
358 {
359 	struct adt7410_data *data;
360 	int ret;
361 
362 	if (!i2c_check_functionality(client->adapter,
363 			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
364 		return -ENODEV;
365 
366 	data = devm_kzalloc(&client->dev, sizeof(struct adt7410_data),
367 			    GFP_KERNEL);
368 	if (!data)
369 		return -ENOMEM;
370 
371 	i2c_set_clientdata(client, data);
372 	mutex_init(&data->update_lock);
373 
374 	/* configure as specified */
375 	ret = i2c_smbus_read_byte_data(client, ADT7410_CONFIG);
376 	if (ret < 0) {
377 		dev_dbg(&client->dev, "Can't read config? %d\n", ret);
378 		return ret;
379 	}
380 	data->oldconfig = ret;
381 	/*
382 	 * Set to 16 bit resolution, continous conversion and comparator mode.
383 	 */
384 	ret &= ~ADT7410_MODE_MASK;
385 	data->config = ret | ADT7410_FULL | ADT7410_RESOLUTION |
386 			ADT7410_EVENT_MODE;
387 	if (data->config != data->oldconfig) {
388 		ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
389 						data->config);
390 		if (ret)
391 			return ret;
392 	}
393 	dev_dbg(&client->dev, "Config %02x\n", data->config);
394 
395 	ret = adt7410_fill_cache(client);
396 	if (ret)
397 		goto exit_restore;
398 
399 	/* Register sysfs hooks */
400 	ret = sysfs_create_group(&client->dev.kobj, &adt7410_group);
401 	if (ret)
402 		goto exit_restore;
403 
404 	data->hwmon_dev = hwmon_device_register(&client->dev);
405 	if (IS_ERR(data->hwmon_dev)) {
406 		ret = PTR_ERR(data->hwmon_dev);
407 		goto exit_remove;
408 	}
409 
410 	dev_info(&client->dev, "sensor '%s'\n", client->name);
411 
412 	return 0;
413 
414 exit_remove:
415 	sysfs_remove_group(&client->dev.kobj, &adt7410_group);
416 exit_restore:
417 	i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->oldconfig);
418 	return ret;
419 }
420 
421 static int adt7410_remove(struct i2c_client *client)
422 {
423 	struct adt7410_data *data = i2c_get_clientdata(client);
424 
425 	hwmon_device_unregister(data->hwmon_dev);
426 	sysfs_remove_group(&client->dev.kobj, &adt7410_group);
427 	if (data->oldconfig != data->config)
428 		i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
429 					  data->oldconfig);
430 	return 0;
431 }
432 
433 static const struct i2c_device_id adt7410_ids[] = {
434 	{ "adt7410", adt7410, },
435 	{ "adt7420", adt7410, },
436 	{ /* LIST END */ }
437 };
438 MODULE_DEVICE_TABLE(i2c, adt7410_ids);
439 
440 #ifdef CONFIG_PM_SLEEP
441 static int adt7410_suspend(struct device *dev)
442 {
443 	int ret;
444 	struct i2c_client *client = to_i2c_client(dev);
445 	struct adt7410_data *data = i2c_get_clientdata(client);
446 
447 	ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
448 					data->config | ADT7410_PD);
449 	return ret;
450 }
451 
452 static int adt7410_resume(struct device *dev)
453 {
454 	int ret;
455 	struct i2c_client *client = to_i2c_client(dev);
456 	struct adt7410_data *data = i2c_get_clientdata(client);
457 
458 	ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->config);
459 	return ret;
460 }
461 
462 static SIMPLE_DEV_PM_OPS(adt7410_dev_pm_ops, adt7410_suspend, adt7410_resume);
463 
464 #define ADT7410_DEV_PM_OPS (&adt7410_dev_pm_ops)
465 #else
466 #define ADT7410_DEV_PM_OPS NULL
467 #endif /* CONFIG_PM */
468 
469 static struct i2c_driver adt7410_driver = {
470 	.class		= I2C_CLASS_HWMON,
471 	.driver = {
472 		.name	= "adt7410",
473 		.pm	= ADT7410_DEV_PM_OPS,
474 	},
475 	.probe		= adt7410_probe,
476 	.remove		= adt7410_remove,
477 	.id_table	= adt7410_ids,
478 	.address_list	= I2C_ADDRS(0x48, 0x49, 0x4a, 0x4b),
479 };
480 
481 module_i2c_driver(adt7410_driver);
482 
483 MODULE_AUTHOR("Hartmut Knaack");
484 MODULE_DESCRIPTION("ADT7410/ADT7420 driver");
485 MODULE_LICENSE("GPL");
486