xref: /openbmc/linux/drivers/hwmon/adc128d818.c (revision 92b19ff5)
1 /*
2  * Driver for TI ADC128D818 System Monitor with Temperature Sensor
3  *
4  * Copyright (c) 2014 Guenter Roeck
5  *
6  * Derived from lm80.c
7  * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
8  *			     and Philip Edelbrock <phil@netroedge.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  */
20 
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/jiffies.h>
24 #include <linux/i2c.h>
25 #include <linux/hwmon.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/err.h>
28 #include <linux/regulator/consumer.h>
29 #include <linux/mutex.h>
30 #include <linux/bitops.h>
31 
32 /* Addresses to scan
33  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
34  * since they are also used by some EEPROMs, which may result in false
35  * positives.
36  */
37 static const unsigned short normal_i2c[] = {
38 	0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
39 
40 /* registers */
41 #define ADC128_REG_IN_MAX(nr)		(0x2a + (nr) * 2)
42 #define ADC128_REG_IN_MIN(nr)		(0x2b + (nr) * 2)
43 #define ADC128_REG_IN(nr)		(0x20 + (nr))
44 
45 #define ADC128_REG_TEMP			0x27
46 #define ADC128_REG_TEMP_MAX		0x38
47 #define ADC128_REG_TEMP_HYST		0x39
48 
49 #define ADC128_REG_CONFIG		0x00
50 #define ADC128_REG_ALARM		0x01
51 #define ADC128_REG_MASK			0x03
52 #define ADC128_REG_CONV_RATE		0x07
53 #define ADC128_REG_ONESHOT		0x09
54 #define ADC128_REG_SHUTDOWN		0x0a
55 #define ADC128_REG_CONFIG_ADV		0x0b
56 #define ADC128_REG_BUSY_STATUS		0x0c
57 
58 #define ADC128_REG_MAN_ID		0x3e
59 #define ADC128_REG_DEV_ID		0x3f
60 
61 struct adc128_data {
62 	struct i2c_client *client;
63 	struct regulator *regulator;
64 	int vref;		/* Reference voltage in mV */
65 	struct mutex update_lock;
66 	bool valid;		/* true if following fields are valid */
67 	unsigned long last_updated;	/* In jiffies */
68 
69 	u16 in[3][7];		/* Register value, normalized to 12 bit
70 				 * 0: input voltage
71 				 * 1: min limit
72 				 * 2: max limit
73 				 */
74 	s16 temp[3];		/* Register value, normalized to 9 bit
75 				 * 0: sensor 1: limit 2: hyst
76 				 */
77 	u8 alarms;		/* alarm register value */
78 };
79 
80 static struct adc128_data *adc128_update_device(struct device *dev)
81 {
82 	struct adc128_data *data = dev_get_drvdata(dev);
83 	struct i2c_client *client = data->client;
84 	struct adc128_data *ret = data;
85 	int i, rv;
86 
87 	mutex_lock(&data->update_lock);
88 
89 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
90 		for (i = 0; i < 7; i++) {
91 			rv = i2c_smbus_read_word_swapped(client,
92 							 ADC128_REG_IN(i));
93 			if (rv < 0)
94 				goto abort;
95 			data->in[0][i] = rv >> 4;
96 
97 			rv = i2c_smbus_read_byte_data(client,
98 						      ADC128_REG_IN_MIN(i));
99 			if (rv < 0)
100 				goto abort;
101 			data->in[1][i] = rv << 4;
102 
103 			rv = i2c_smbus_read_byte_data(client,
104 						      ADC128_REG_IN_MAX(i));
105 			if (rv < 0)
106 				goto abort;
107 			data->in[2][i] = rv << 4;
108 		}
109 
110 		rv = i2c_smbus_read_word_swapped(client, ADC128_REG_TEMP);
111 		if (rv < 0)
112 			goto abort;
113 		data->temp[0] = rv >> 7;
114 
115 		rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_MAX);
116 		if (rv < 0)
117 			goto abort;
118 		data->temp[1] = rv << 1;
119 
120 		rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_HYST);
121 		if (rv < 0)
122 			goto abort;
123 		data->temp[2] = rv << 1;
124 
125 		rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
126 		if (rv < 0)
127 			goto abort;
128 		data->alarms |= rv;
129 
130 		data->last_updated = jiffies;
131 		data->valid = true;
132 	}
133 	goto done;
134 
135 abort:
136 	ret = ERR_PTR(rv);
137 	data->valid = false;
138 done:
139 	mutex_unlock(&data->update_lock);
140 	return ret;
141 }
142 
143 static ssize_t adc128_show_in(struct device *dev, struct device_attribute *attr,
144 			      char *buf)
145 {
146 	struct adc128_data *data = adc128_update_device(dev);
147 	int index = to_sensor_dev_attr_2(attr)->index;
148 	int nr = to_sensor_dev_attr_2(attr)->nr;
149 	int val;
150 
151 	if (IS_ERR(data))
152 		return PTR_ERR(data);
153 
154 	val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
155 	return sprintf(buf, "%d\n", val);
156 }
157 
158 static ssize_t adc128_set_in(struct device *dev, struct device_attribute *attr,
159 			     const char *buf, size_t count)
160 {
161 	struct adc128_data *data = dev_get_drvdata(dev);
162 	int index = to_sensor_dev_attr_2(attr)->index;
163 	int nr = to_sensor_dev_attr_2(attr)->nr;
164 	u8 reg, regval;
165 	long val;
166 	int err;
167 
168 	err = kstrtol(buf, 10, &val);
169 	if (err < 0)
170 		return err;
171 
172 	mutex_lock(&data->update_lock);
173 	/* 10 mV LSB on limit registers */
174 	regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
175 	data->in[index][nr] = regval << 4;
176 	reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
177 	i2c_smbus_write_byte_data(data->client, reg, regval);
178 	mutex_unlock(&data->update_lock);
179 
180 	return count;
181 }
182 
183 static ssize_t adc128_show_temp(struct device *dev,
184 				struct device_attribute *attr, char *buf)
185 {
186 	struct adc128_data *data = adc128_update_device(dev);
187 	int index = to_sensor_dev_attr(attr)->index;
188 	int temp;
189 
190 	if (IS_ERR(data))
191 		return PTR_ERR(data);
192 
193 	temp = sign_extend32(data->temp[index], 8);
194 	return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
195 }
196 
197 static ssize_t adc128_set_temp(struct device *dev,
198 			       struct device_attribute *attr,
199 			       const char *buf, size_t count)
200 {
201 	struct adc128_data *data = dev_get_drvdata(dev);
202 	int index = to_sensor_dev_attr(attr)->index;
203 	long val;
204 	int err;
205 	s8 regval;
206 
207 	err = kstrtol(buf, 10, &val);
208 	if (err < 0)
209 		return err;
210 
211 	mutex_lock(&data->update_lock);
212 	regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
213 	data->temp[index] = regval << 1;
214 	i2c_smbus_write_byte_data(data->client,
215 				  index == 1 ? ADC128_REG_TEMP_MAX
216 					     : ADC128_REG_TEMP_HYST,
217 				  regval);
218 	mutex_unlock(&data->update_lock);
219 
220 	return count;
221 }
222 
223 static ssize_t adc128_show_alarm(struct device *dev,
224 				 struct device_attribute *attr, char *buf)
225 {
226 	struct adc128_data *data = adc128_update_device(dev);
227 	int mask = 1 << to_sensor_dev_attr(attr)->index;
228 	u8 alarms;
229 
230 	if (IS_ERR(data))
231 		return PTR_ERR(data);
232 
233 	/*
234 	 * Clear an alarm after reporting it to user space. If it is still
235 	 * active, the next update sequence will set the alarm bit again.
236 	 */
237 	alarms = data->alarms;
238 	data->alarms &= ~mask;
239 
240 	return sprintf(buf, "%u\n", !!(alarms & mask));
241 }
242 
243 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO,
244 			    adc128_show_in, NULL, 0, 0);
245 static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO,
246 			    adc128_show_in, adc128_set_in, 0, 1);
247 static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO,
248 			    adc128_show_in, adc128_set_in, 0, 2);
249 
250 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO,
251 			    adc128_show_in, NULL, 1, 0);
252 static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO,
253 			    adc128_show_in, adc128_set_in, 1, 1);
254 static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO,
255 			    adc128_show_in, adc128_set_in, 1, 2);
256 
257 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO,
258 			    adc128_show_in, NULL, 2, 0);
259 static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO,
260 			    adc128_show_in, adc128_set_in, 2, 1);
261 static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO,
262 			    adc128_show_in, adc128_set_in, 2, 2);
263 
264 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO,
265 			    adc128_show_in, NULL, 3, 0);
266 static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO,
267 			    adc128_show_in, adc128_set_in, 3, 1);
268 static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO,
269 			    adc128_show_in, adc128_set_in, 3, 2);
270 
271 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO,
272 			    adc128_show_in, NULL, 4, 0);
273 static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO,
274 			    adc128_show_in, adc128_set_in, 4, 1);
275 static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO,
276 			    adc128_show_in, adc128_set_in, 4, 2);
277 
278 static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO,
279 			    adc128_show_in, NULL, 5, 0);
280 static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO,
281 			    adc128_show_in, adc128_set_in, 5, 1);
282 static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO,
283 			    adc128_show_in, adc128_set_in, 5, 2);
284 
285 static SENSOR_DEVICE_ATTR_2(in6_input, S_IRUGO,
286 			    adc128_show_in, NULL, 6, 0);
287 static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO,
288 			    adc128_show_in, adc128_set_in, 6, 1);
289 static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO,
290 			    adc128_show_in, adc128_set_in, 6, 2);
291 
292 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adc128_show_temp, NULL, 0);
293 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
294 			  adc128_show_temp, adc128_set_temp, 1);
295 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
296 			  adc128_show_temp, adc128_set_temp, 2);
297 
298 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, adc128_show_alarm, NULL, 0);
299 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, adc128_show_alarm, NULL, 1);
300 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, adc128_show_alarm, NULL, 2);
301 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, adc128_show_alarm, NULL, 3);
302 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, adc128_show_alarm, NULL, 4);
303 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, adc128_show_alarm, NULL, 5);
304 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, adc128_show_alarm, NULL, 6);
305 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adc128_show_alarm, NULL, 7);
306 
307 static struct attribute *adc128_attrs[] = {
308 	&sensor_dev_attr_in0_min.dev_attr.attr,
309 	&sensor_dev_attr_in1_min.dev_attr.attr,
310 	&sensor_dev_attr_in2_min.dev_attr.attr,
311 	&sensor_dev_attr_in3_min.dev_attr.attr,
312 	&sensor_dev_attr_in4_min.dev_attr.attr,
313 	&sensor_dev_attr_in5_min.dev_attr.attr,
314 	&sensor_dev_attr_in6_min.dev_attr.attr,
315 	&sensor_dev_attr_in0_max.dev_attr.attr,
316 	&sensor_dev_attr_in1_max.dev_attr.attr,
317 	&sensor_dev_attr_in2_max.dev_attr.attr,
318 	&sensor_dev_attr_in3_max.dev_attr.attr,
319 	&sensor_dev_attr_in4_max.dev_attr.attr,
320 	&sensor_dev_attr_in5_max.dev_attr.attr,
321 	&sensor_dev_attr_in6_max.dev_attr.attr,
322 	&sensor_dev_attr_in0_input.dev_attr.attr,
323 	&sensor_dev_attr_in1_input.dev_attr.attr,
324 	&sensor_dev_attr_in2_input.dev_attr.attr,
325 	&sensor_dev_attr_in3_input.dev_attr.attr,
326 	&sensor_dev_attr_in4_input.dev_attr.attr,
327 	&sensor_dev_attr_in5_input.dev_attr.attr,
328 	&sensor_dev_attr_in6_input.dev_attr.attr,
329 	&sensor_dev_attr_temp1_input.dev_attr.attr,
330 	&sensor_dev_attr_temp1_max.dev_attr.attr,
331 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
332 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
333 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
334 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
335 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
336 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
337 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
338 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
339 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
340 	NULL
341 };
342 ATTRIBUTE_GROUPS(adc128);
343 
344 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
345 {
346 	int man_id, dev_id;
347 
348 	if (!i2c_check_functionality(client->adapter,
349 				     I2C_FUNC_SMBUS_BYTE_DATA |
350 				     I2C_FUNC_SMBUS_WORD_DATA))
351 		return -ENODEV;
352 
353 	man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
354 	dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
355 	if (man_id != 0x01 || dev_id != 0x09)
356 		return -ENODEV;
357 
358 	/* Check unused bits for confirmation */
359 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
360 		return -ENODEV;
361 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
362 		return -ENODEV;
363 	if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
364 		return -ENODEV;
365 	if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
366 		return -ENODEV;
367 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
368 		return -ENODEV;
369 	if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
370 		return -ENODEV;
371 
372 	strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
373 
374 	return 0;
375 }
376 
377 static int adc128_init_client(struct adc128_data *data)
378 {
379 	struct i2c_client *client = data->client;
380 	int err;
381 
382 	/*
383 	 * Reset chip to defaults.
384 	 * This makes most other initializations unnecessary.
385 	 */
386 	err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
387 	if (err)
388 		return err;
389 
390 	/* Start monitoring */
391 	err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
392 	if (err)
393 		return err;
394 
395 	/* If external vref is selected, configure the chip to use it */
396 	if (data->regulator) {
397 		err = i2c_smbus_write_byte_data(client,
398 						ADC128_REG_CONFIG_ADV, 0x01);
399 		if (err)
400 			return err;
401 	}
402 
403 	return 0;
404 }
405 
406 static int adc128_probe(struct i2c_client *client,
407 			const struct i2c_device_id *id)
408 {
409 	struct device *dev = &client->dev;
410 	struct regulator *regulator;
411 	struct device *hwmon_dev;
412 	struct adc128_data *data;
413 	int err, vref;
414 
415 	data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
416 	if (!data)
417 		return -ENOMEM;
418 
419 	/* vref is optional. If specified, is used as chip reference voltage */
420 	regulator = devm_regulator_get_optional(dev, "vref");
421 	if (!IS_ERR(regulator)) {
422 		data->regulator = regulator;
423 		err = regulator_enable(regulator);
424 		if (err < 0)
425 			return err;
426 		vref = regulator_get_voltage(regulator);
427 		if (vref < 0) {
428 			err = vref;
429 			goto error;
430 		}
431 		data->vref = DIV_ROUND_CLOSEST(vref, 1000);
432 	} else {
433 		data->vref = 2560;	/* 2.56V, in mV */
434 	}
435 
436 	data->client = client;
437 	i2c_set_clientdata(client, data);
438 	mutex_init(&data->update_lock);
439 
440 	/* Initialize the chip */
441 	err = adc128_init_client(data);
442 	if (err < 0)
443 		goto error;
444 
445 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
446 							   data, adc128_groups);
447 	if (IS_ERR(hwmon_dev)) {
448 		err = PTR_ERR(hwmon_dev);
449 		goto error;
450 	}
451 
452 	return 0;
453 
454 error:
455 	if (data->regulator)
456 		regulator_disable(data->regulator);
457 	return err;
458 }
459 
460 static int adc128_remove(struct i2c_client *client)
461 {
462 	struct adc128_data *data = i2c_get_clientdata(client);
463 
464 	if (data->regulator)
465 		regulator_disable(data->regulator);
466 
467 	return 0;
468 }
469 
470 static const struct i2c_device_id adc128_id[] = {
471 	{ "adc128d818", 0 },
472 	{ }
473 };
474 MODULE_DEVICE_TABLE(i2c, adc128_id);
475 
476 static struct i2c_driver adc128_driver = {
477 	.class		= I2C_CLASS_HWMON,
478 	.driver = {
479 		.name	= "adc128d818",
480 	},
481 	.probe		= adc128_probe,
482 	.remove		= adc128_remove,
483 	.id_table	= adc128_id,
484 	.detect		= adc128_detect,
485 	.address_list	= normal_i2c,
486 };
487 
488 module_i2c_driver(adc128_driver);
489 
490 MODULE_AUTHOR("Guenter Roeck");
491 MODULE_DESCRIPTION("Driver for ADC128D818");
492 MODULE_LICENSE("GPL");
493