xref: /linux/drivers/hwmon/adc128d818.c (revision 37744feebc086908fd89760650f458ab19071750)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for TI ADC128D818 System Monitor with Temperature Sensor
4  *
5  * Copyright (c) 2014 Guenter Roeck
6  *
7  * Derived from lm80.c
8  * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
9  *			     and Philip Edelbrock <phil@netroedge.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/jiffies.h>
15 #include <linux/i2c.h>
16 #include <linux/hwmon.h>
17 #include <linux/hwmon-sysfs.h>
18 #include <linux/err.h>
19 #include <linux/regulator/consumer.h>
20 #include <linux/mutex.h>
21 #include <linux/bitops.h>
22 #include <linux/of.h>
23 
24 /* Addresses to scan
25  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
26  * since they are also used by some EEPROMs, which may result in false
27  * positives.
28  */
29 static const unsigned short normal_i2c[] = {
30 	0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
31 
32 /* registers */
33 #define ADC128_REG_IN_MAX(nr)		(0x2a + (nr) * 2)
34 #define ADC128_REG_IN_MIN(nr)		(0x2b + (nr) * 2)
35 #define ADC128_REG_IN(nr)		(0x20 + (nr))
36 
37 #define ADC128_REG_TEMP			0x27
38 #define ADC128_REG_TEMP_MAX		0x38
39 #define ADC128_REG_TEMP_HYST		0x39
40 
41 #define ADC128_REG_CONFIG		0x00
42 #define ADC128_REG_ALARM		0x01
43 #define ADC128_REG_MASK			0x03
44 #define ADC128_REG_CONV_RATE		0x07
45 #define ADC128_REG_ONESHOT		0x09
46 #define ADC128_REG_SHUTDOWN		0x0a
47 #define ADC128_REG_CONFIG_ADV		0x0b
48 #define ADC128_REG_BUSY_STATUS		0x0c
49 
50 #define ADC128_REG_MAN_ID		0x3e
51 #define ADC128_REG_DEV_ID		0x3f
52 
53 /* No. of voltage entries in adc128_attrs */
54 #define ADC128_ATTR_NUM_VOLT		(8 * 4)
55 
56 /* Voltage inputs visible per operation mode */
57 static const u8 num_inputs[] = { 7, 8, 4, 6 };
58 
59 struct adc128_data {
60 	struct i2c_client *client;
61 	struct regulator *regulator;
62 	int vref;		/* Reference voltage in mV */
63 	struct mutex update_lock;
64 	u8 mode;		/* Operation mode */
65 	bool valid;		/* true if following fields are valid */
66 	unsigned long last_updated;	/* In jiffies */
67 
68 	u16 in[3][8];		/* Register value, normalized to 12 bit
69 				 * 0: input voltage
70 				 * 1: min limit
71 				 * 2: max limit
72 				 */
73 	s16 temp[3];		/* Register value, normalized to 9 bit
74 				 * 0: sensor 1: limit 2: hyst
75 				 */
76 	u8 alarms;		/* alarm register value */
77 };
78 
79 static struct adc128_data *adc128_update_device(struct device *dev)
80 {
81 	struct adc128_data *data = dev_get_drvdata(dev);
82 	struct i2c_client *client = data->client;
83 	struct adc128_data *ret = data;
84 	int i, rv;
85 
86 	mutex_lock(&data->update_lock);
87 
88 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
89 		for (i = 0; i < num_inputs[data->mode]; i++) {
90 			rv = i2c_smbus_read_word_swapped(client,
91 							 ADC128_REG_IN(i));
92 			if (rv < 0)
93 				goto abort;
94 			data->in[0][i] = rv >> 4;
95 
96 			rv = i2c_smbus_read_byte_data(client,
97 						      ADC128_REG_IN_MIN(i));
98 			if (rv < 0)
99 				goto abort;
100 			data->in[1][i] = rv << 4;
101 
102 			rv = i2c_smbus_read_byte_data(client,
103 						      ADC128_REG_IN_MAX(i));
104 			if (rv < 0)
105 				goto abort;
106 			data->in[2][i] = rv << 4;
107 		}
108 
109 		if (data->mode != 1) {
110 			rv = i2c_smbus_read_word_swapped(client,
111 							 ADC128_REG_TEMP);
112 			if (rv < 0)
113 				goto abort;
114 			data->temp[0] = rv >> 7;
115 
116 			rv = i2c_smbus_read_byte_data(client,
117 						      ADC128_REG_TEMP_MAX);
118 			if (rv < 0)
119 				goto abort;
120 			data->temp[1] = rv << 1;
121 
122 			rv = i2c_smbus_read_byte_data(client,
123 						      ADC128_REG_TEMP_HYST);
124 			if (rv < 0)
125 				goto abort;
126 			data->temp[2] = rv << 1;
127 		}
128 
129 		rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
130 		if (rv < 0)
131 			goto abort;
132 		data->alarms |= rv;
133 
134 		data->last_updated = jiffies;
135 		data->valid = true;
136 	}
137 	goto done;
138 
139 abort:
140 	ret = ERR_PTR(rv);
141 	data->valid = false;
142 done:
143 	mutex_unlock(&data->update_lock);
144 	return ret;
145 }
146 
147 static ssize_t adc128_in_show(struct device *dev,
148 			      struct device_attribute *attr, char *buf)
149 {
150 	struct adc128_data *data = adc128_update_device(dev);
151 	int index = to_sensor_dev_attr_2(attr)->index;
152 	int nr = to_sensor_dev_attr_2(attr)->nr;
153 	int val;
154 
155 	if (IS_ERR(data))
156 		return PTR_ERR(data);
157 
158 	val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
159 	return sprintf(buf, "%d\n", val);
160 }
161 
162 static ssize_t adc128_in_store(struct device *dev,
163 			       struct device_attribute *attr, const char *buf,
164 			       size_t count)
165 {
166 	struct adc128_data *data = dev_get_drvdata(dev);
167 	int index = to_sensor_dev_attr_2(attr)->index;
168 	int nr = to_sensor_dev_attr_2(attr)->nr;
169 	u8 reg, regval;
170 	long val;
171 	int err;
172 
173 	err = kstrtol(buf, 10, &val);
174 	if (err < 0)
175 		return err;
176 
177 	mutex_lock(&data->update_lock);
178 	/* 10 mV LSB on limit registers */
179 	regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
180 	data->in[index][nr] = regval << 4;
181 	reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
182 	i2c_smbus_write_byte_data(data->client, reg, regval);
183 	mutex_unlock(&data->update_lock);
184 
185 	return count;
186 }
187 
188 static ssize_t adc128_temp_show(struct device *dev,
189 				struct device_attribute *attr, char *buf)
190 {
191 	struct adc128_data *data = adc128_update_device(dev);
192 	int index = to_sensor_dev_attr(attr)->index;
193 	int temp;
194 
195 	if (IS_ERR(data))
196 		return PTR_ERR(data);
197 
198 	temp = sign_extend32(data->temp[index], 8);
199 	return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
200 }
201 
202 static ssize_t adc128_temp_store(struct device *dev,
203 				 struct device_attribute *attr,
204 				 const char *buf, size_t count)
205 {
206 	struct adc128_data *data = dev_get_drvdata(dev);
207 	int index = to_sensor_dev_attr(attr)->index;
208 	long val;
209 	int err;
210 	s8 regval;
211 
212 	err = kstrtol(buf, 10, &val);
213 	if (err < 0)
214 		return err;
215 
216 	mutex_lock(&data->update_lock);
217 	regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
218 	data->temp[index] = regval << 1;
219 	i2c_smbus_write_byte_data(data->client,
220 				  index == 1 ? ADC128_REG_TEMP_MAX
221 					     : ADC128_REG_TEMP_HYST,
222 				  regval);
223 	mutex_unlock(&data->update_lock);
224 
225 	return count;
226 }
227 
228 static ssize_t adc128_alarm_show(struct device *dev,
229 				 struct device_attribute *attr, char *buf)
230 {
231 	struct adc128_data *data = adc128_update_device(dev);
232 	int mask = 1 << to_sensor_dev_attr(attr)->index;
233 	u8 alarms;
234 
235 	if (IS_ERR(data))
236 		return PTR_ERR(data);
237 
238 	/*
239 	 * Clear an alarm after reporting it to user space. If it is still
240 	 * active, the next update sequence will set the alarm bit again.
241 	 */
242 	alarms = data->alarms;
243 	data->alarms &= ~mask;
244 
245 	return sprintf(buf, "%u\n", !!(alarms & mask));
246 }
247 
248 static umode_t adc128_is_visible(struct kobject *kobj,
249 				 struct attribute *attr, int index)
250 {
251 	struct device *dev = container_of(kobj, struct device, kobj);
252 	struct adc128_data *data = dev_get_drvdata(dev);
253 
254 	if (index < ADC128_ATTR_NUM_VOLT) {
255 		/* Voltage, visible according to num_inputs[] */
256 		if (index >= num_inputs[data->mode] * 4)
257 			return 0;
258 	} else {
259 		/* Temperature, visible if not in mode 1 */
260 		if (data->mode == 1)
261 			return 0;
262 	}
263 
264 	return attr->mode;
265 }
266 
267 static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
268 static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
269 static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
270 
271 static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
272 static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
273 static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
274 
275 static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
276 static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
277 static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
278 
279 static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
280 static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
281 static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
282 
283 static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
284 static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
285 static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
286 
287 static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
288 static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
289 static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
290 
291 static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
292 static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
293 static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
294 
295 static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
296 static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
297 static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
298 
299 static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
300 static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
301 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
302 
303 static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
304 static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
305 static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
306 static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
307 static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
308 static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
309 static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
310 static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
311 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
312 
313 static struct attribute *adc128_attrs[] = {
314 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
315 	&sensor_dev_attr_in0_input.dev_attr.attr,
316 	&sensor_dev_attr_in0_max.dev_attr.attr,
317 	&sensor_dev_attr_in0_min.dev_attr.attr,
318 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
319 	&sensor_dev_attr_in1_input.dev_attr.attr,
320 	&sensor_dev_attr_in1_max.dev_attr.attr,
321 	&sensor_dev_attr_in1_min.dev_attr.attr,
322 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
323 	&sensor_dev_attr_in2_input.dev_attr.attr,
324 	&sensor_dev_attr_in2_max.dev_attr.attr,
325 	&sensor_dev_attr_in2_min.dev_attr.attr,
326 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
327 	&sensor_dev_attr_in3_input.dev_attr.attr,
328 	&sensor_dev_attr_in3_max.dev_attr.attr,
329 	&sensor_dev_attr_in3_min.dev_attr.attr,
330 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
331 	&sensor_dev_attr_in4_input.dev_attr.attr,
332 	&sensor_dev_attr_in4_max.dev_attr.attr,
333 	&sensor_dev_attr_in4_min.dev_attr.attr,
334 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
335 	&sensor_dev_attr_in5_input.dev_attr.attr,
336 	&sensor_dev_attr_in5_max.dev_attr.attr,
337 	&sensor_dev_attr_in5_min.dev_attr.attr,
338 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
339 	&sensor_dev_attr_in6_input.dev_attr.attr,
340 	&sensor_dev_attr_in6_max.dev_attr.attr,
341 	&sensor_dev_attr_in6_min.dev_attr.attr,
342 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
343 	&sensor_dev_attr_in7_input.dev_attr.attr,
344 	&sensor_dev_attr_in7_max.dev_attr.attr,
345 	&sensor_dev_attr_in7_min.dev_attr.attr,
346 	&sensor_dev_attr_temp1_input.dev_attr.attr,
347 	&sensor_dev_attr_temp1_max.dev_attr.attr,
348 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
349 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
350 	NULL
351 };
352 
353 static const struct attribute_group adc128_group = {
354 	.attrs = adc128_attrs,
355 	.is_visible = adc128_is_visible,
356 };
357 __ATTRIBUTE_GROUPS(adc128);
358 
359 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
360 {
361 	int man_id, dev_id;
362 
363 	if (!i2c_check_functionality(client->adapter,
364 				     I2C_FUNC_SMBUS_BYTE_DATA |
365 				     I2C_FUNC_SMBUS_WORD_DATA))
366 		return -ENODEV;
367 
368 	man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
369 	dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
370 	if (man_id != 0x01 || dev_id != 0x09)
371 		return -ENODEV;
372 
373 	/* Check unused bits for confirmation */
374 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
375 		return -ENODEV;
376 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
377 		return -ENODEV;
378 	if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
379 		return -ENODEV;
380 	if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
381 		return -ENODEV;
382 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
383 		return -ENODEV;
384 	if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
385 		return -ENODEV;
386 
387 	strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
388 
389 	return 0;
390 }
391 
392 static int adc128_init_client(struct adc128_data *data)
393 {
394 	struct i2c_client *client = data->client;
395 	int err;
396 
397 	/*
398 	 * Reset chip to defaults.
399 	 * This makes most other initializations unnecessary.
400 	 */
401 	err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
402 	if (err)
403 		return err;
404 
405 	/* Set operation mode, if non-default */
406 	if (data->mode != 0) {
407 		err = i2c_smbus_write_byte_data(client,
408 						ADC128_REG_CONFIG_ADV,
409 						data->mode << 1);
410 		if (err)
411 			return err;
412 	}
413 
414 	/* Start monitoring */
415 	err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
416 	if (err)
417 		return err;
418 
419 	/* If external vref is selected, configure the chip to use it */
420 	if (data->regulator) {
421 		err = i2c_smbus_write_byte_data(client,
422 						ADC128_REG_CONFIG_ADV, 0x01);
423 		if (err)
424 			return err;
425 	}
426 
427 	return 0;
428 }
429 
430 static int adc128_probe(struct i2c_client *client,
431 			const struct i2c_device_id *id)
432 {
433 	struct device *dev = &client->dev;
434 	struct regulator *regulator;
435 	struct device *hwmon_dev;
436 	struct adc128_data *data;
437 	int err, vref;
438 
439 	data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
440 	if (!data)
441 		return -ENOMEM;
442 
443 	/* vref is optional. If specified, is used as chip reference voltage */
444 	regulator = devm_regulator_get_optional(dev, "vref");
445 	if (!IS_ERR(regulator)) {
446 		data->regulator = regulator;
447 		err = regulator_enable(regulator);
448 		if (err < 0)
449 			return err;
450 		vref = regulator_get_voltage(regulator);
451 		if (vref < 0) {
452 			err = vref;
453 			goto error;
454 		}
455 		data->vref = DIV_ROUND_CLOSEST(vref, 1000);
456 	} else {
457 		data->vref = 2560;	/* 2.56V, in mV */
458 	}
459 
460 	/* Operation mode is optional. If unspecified, keep current mode */
461 	if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
462 		if (data->mode > 3) {
463 			dev_err(dev, "invalid operation mode %d\n",
464 				data->mode);
465 			err = -EINVAL;
466 			goto error;
467 		}
468 	} else {
469 		err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
470 		if (err < 0)
471 			goto error;
472 		data->mode = (err >> 1) & ADC128_REG_MASK;
473 	}
474 
475 	data->client = client;
476 	i2c_set_clientdata(client, data);
477 	mutex_init(&data->update_lock);
478 
479 	/* Initialize the chip */
480 	err = adc128_init_client(data);
481 	if (err < 0)
482 		goto error;
483 
484 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
485 							   data, adc128_groups);
486 	if (IS_ERR(hwmon_dev)) {
487 		err = PTR_ERR(hwmon_dev);
488 		goto error;
489 	}
490 
491 	return 0;
492 
493 error:
494 	if (data->regulator)
495 		regulator_disable(data->regulator);
496 	return err;
497 }
498 
499 static int adc128_remove(struct i2c_client *client)
500 {
501 	struct adc128_data *data = i2c_get_clientdata(client);
502 
503 	if (data->regulator)
504 		regulator_disable(data->regulator);
505 
506 	return 0;
507 }
508 
509 static const struct i2c_device_id adc128_id[] = {
510 	{ "adc128d818", 0 },
511 	{ }
512 };
513 MODULE_DEVICE_TABLE(i2c, adc128_id);
514 
515 static const struct of_device_id __maybe_unused adc128_of_match[] = {
516 	{ .compatible = "ti,adc128d818" },
517 	{ },
518 };
519 MODULE_DEVICE_TABLE(of, adc128_of_match);
520 
521 static struct i2c_driver adc128_driver = {
522 	.class		= I2C_CLASS_HWMON,
523 	.driver = {
524 		.name	= "adc128d818",
525 		.of_match_table = of_match_ptr(adc128_of_match),
526 	},
527 	.probe		= adc128_probe,
528 	.remove		= adc128_remove,
529 	.id_table	= adc128_id,
530 	.detect		= adc128_detect,
531 	.address_list	= normal_i2c,
532 };
533 
534 module_i2c_driver(adc128_driver);
535 
536 MODULE_AUTHOR("Guenter Roeck");
537 MODULE_DESCRIPTION("Driver for ADC128D818");
538 MODULE_LICENSE("GPL");
539