xref: /linux/drivers/hwmon/adc128d818.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 	int vref;		/* Reference voltage in mV */
62 	struct mutex update_lock;
63 	u8 mode;		/* Operation mode */
64 	bool valid;		/* true if following fields are valid */
65 	unsigned long last_updated;	/* In jiffies */
66 
67 	u16 in[3][8];		/* Register value, normalized to 12 bit
68 				 * 0: input voltage
69 				 * 1: min limit
70 				 * 2: max limit
71 				 */
72 	s16 temp[3];		/* Register value, normalized to 9 bit
73 				 * 0: sensor 1: limit 2: hyst
74 				 */
75 	u8 alarms;		/* alarm register value */
76 };
77 
78 static struct adc128_data *adc128_update_device(struct device *dev)
79 {
80 	struct adc128_data *data = dev_get_drvdata(dev);
81 	struct i2c_client *client = data->client;
82 	struct adc128_data *ret = data;
83 	int i, rv;
84 
85 	mutex_lock(&data->update_lock);
86 
87 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
88 		for (i = 0; i < num_inputs[data->mode]; i++) {
89 			rv = i2c_smbus_read_word_swapped(client,
90 							 ADC128_REG_IN(i));
91 			if (rv < 0)
92 				goto abort;
93 			data->in[0][i] = rv >> 4;
94 
95 			rv = i2c_smbus_read_byte_data(client,
96 						      ADC128_REG_IN_MIN(i));
97 			if (rv < 0)
98 				goto abort;
99 			data->in[1][i] = rv << 4;
100 
101 			rv = i2c_smbus_read_byte_data(client,
102 						      ADC128_REG_IN_MAX(i));
103 			if (rv < 0)
104 				goto abort;
105 			data->in[2][i] = rv << 4;
106 		}
107 
108 		if (data->mode != 1) {
109 			rv = i2c_smbus_read_word_swapped(client,
110 							 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,
116 						      ADC128_REG_TEMP_MAX);
117 			if (rv < 0)
118 				goto abort;
119 			data->temp[1] = rv << 1;
120 
121 			rv = i2c_smbus_read_byte_data(client,
122 						      ADC128_REG_TEMP_HYST);
123 			if (rv < 0)
124 				goto abort;
125 			data->temp[2] = rv << 1;
126 		}
127 
128 		rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
129 		if (rv < 0)
130 			goto abort;
131 		data->alarms |= rv;
132 
133 		data->last_updated = jiffies;
134 		data->valid = true;
135 	}
136 	goto done;
137 
138 abort:
139 	ret = ERR_PTR(rv);
140 	data->valid = false;
141 done:
142 	mutex_unlock(&data->update_lock);
143 	return ret;
144 }
145 
146 static ssize_t adc128_in_show(struct device *dev,
147 			      struct device_attribute *attr, char *buf)
148 {
149 	struct adc128_data *data = adc128_update_device(dev);
150 	int index = to_sensor_dev_attr_2(attr)->index;
151 	int nr = to_sensor_dev_attr_2(attr)->nr;
152 	int val;
153 
154 	if (IS_ERR(data))
155 		return PTR_ERR(data);
156 
157 	val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
158 	return sprintf(buf, "%d\n", val);
159 }
160 
161 static ssize_t adc128_in_store(struct device *dev,
162 			       struct device_attribute *attr, const char *buf,
163 			       size_t count)
164 {
165 	struct adc128_data *data = dev_get_drvdata(dev);
166 	int index = to_sensor_dev_attr_2(attr)->index;
167 	int nr = to_sensor_dev_attr_2(attr)->nr;
168 	u8 reg, regval;
169 	long val;
170 	int err;
171 
172 	err = kstrtol(buf, 10, &val);
173 	if (err < 0)
174 		return err;
175 
176 	mutex_lock(&data->update_lock);
177 	/* 10 mV LSB on limit registers */
178 	regval = DIV_ROUND_CLOSEST(clamp_val(val, 0, 2550), 10);
179 	data->in[index][nr] = regval << 4;
180 	reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
181 	i2c_smbus_write_byte_data(data->client, reg, regval);
182 	mutex_unlock(&data->update_lock);
183 
184 	return count;
185 }
186 
187 static ssize_t adc128_temp_show(struct device *dev,
188 				struct device_attribute *attr, char *buf)
189 {
190 	struct adc128_data *data = adc128_update_device(dev);
191 	int index = to_sensor_dev_attr(attr)->index;
192 	int temp;
193 
194 	if (IS_ERR(data))
195 		return PTR_ERR(data);
196 
197 	temp = sign_extend32(data->temp[index], 8);
198 	return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
199 }
200 
201 static ssize_t adc128_temp_store(struct device *dev,
202 				 struct device_attribute *attr,
203 				 const char *buf, size_t count)
204 {
205 	struct adc128_data *data = dev_get_drvdata(dev);
206 	int index = to_sensor_dev_attr(attr)->index;
207 	long val;
208 	int err;
209 	s8 regval;
210 
211 	err = kstrtol(buf, 10, &val);
212 	if (err < 0)
213 		return err;
214 
215 	mutex_lock(&data->update_lock);
216 	regval = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
217 	data->temp[index] = regval << 1;
218 	i2c_smbus_write_byte_data(data->client,
219 				  index == 1 ? ADC128_REG_TEMP_MAX
220 					     : ADC128_REG_TEMP_HYST,
221 				  regval);
222 	mutex_unlock(&data->update_lock);
223 
224 	return count;
225 }
226 
227 static ssize_t adc128_alarm_show(struct device *dev,
228 				 struct device_attribute *attr, char *buf)
229 {
230 	struct adc128_data *data = adc128_update_device(dev);
231 	int mask = 1 << to_sensor_dev_attr(attr)->index;
232 	u8 alarms;
233 
234 	if (IS_ERR(data))
235 		return PTR_ERR(data);
236 
237 	/*
238 	 * Clear an alarm after reporting it to user space. If it is still
239 	 * active, the next update sequence will set the alarm bit again.
240 	 */
241 	alarms = data->alarms;
242 	data->alarms &= ~mask;
243 
244 	return sprintf(buf, "%u\n", !!(alarms & mask));
245 }
246 
247 static umode_t adc128_is_visible(struct kobject *kobj,
248 				 struct attribute *attr, int index)
249 {
250 	struct device *dev = kobj_to_dev(kobj);
251 	struct adc128_data *data = dev_get_drvdata(dev);
252 
253 	if (index < ADC128_ATTR_NUM_VOLT) {
254 		/* Voltage, visible according to num_inputs[] */
255 		if (index >= num_inputs[data->mode] * 4)
256 			return 0;
257 	} else {
258 		/* Temperature, visible if not in mode 1 */
259 		if (data->mode == 1)
260 			return 0;
261 	}
262 
263 	return attr->mode;
264 }
265 
266 static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
267 static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
268 static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
269 
270 static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
271 static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
272 static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
273 
274 static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
275 static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
276 static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
277 
278 static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
279 static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
280 static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
281 
282 static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
283 static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
284 static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
285 
286 static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
287 static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
288 static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
289 
290 static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
291 static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
292 static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
293 
294 static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
295 static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
296 static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
297 
298 static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
299 static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
300 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
301 
302 static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
303 static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
304 static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
305 static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
306 static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
307 static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
308 static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
309 static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
310 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
311 
312 static struct attribute *adc128_attrs[] = {
313 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
314 	&sensor_dev_attr_in0_input.dev_attr.attr,
315 	&sensor_dev_attr_in0_max.dev_attr.attr,
316 	&sensor_dev_attr_in0_min.dev_attr.attr,
317 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
318 	&sensor_dev_attr_in1_input.dev_attr.attr,
319 	&sensor_dev_attr_in1_max.dev_attr.attr,
320 	&sensor_dev_attr_in1_min.dev_attr.attr,
321 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
322 	&sensor_dev_attr_in2_input.dev_attr.attr,
323 	&sensor_dev_attr_in2_max.dev_attr.attr,
324 	&sensor_dev_attr_in2_min.dev_attr.attr,
325 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
326 	&sensor_dev_attr_in3_input.dev_attr.attr,
327 	&sensor_dev_attr_in3_max.dev_attr.attr,
328 	&sensor_dev_attr_in3_min.dev_attr.attr,
329 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
330 	&sensor_dev_attr_in4_input.dev_attr.attr,
331 	&sensor_dev_attr_in4_max.dev_attr.attr,
332 	&sensor_dev_attr_in4_min.dev_attr.attr,
333 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
334 	&sensor_dev_attr_in5_input.dev_attr.attr,
335 	&sensor_dev_attr_in5_max.dev_attr.attr,
336 	&sensor_dev_attr_in5_min.dev_attr.attr,
337 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
338 	&sensor_dev_attr_in6_input.dev_attr.attr,
339 	&sensor_dev_attr_in6_max.dev_attr.attr,
340 	&sensor_dev_attr_in6_min.dev_attr.attr,
341 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
342 	&sensor_dev_attr_in7_input.dev_attr.attr,
343 	&sensor_dev_attr_in7_max.dev_attr.attr,
344 	&sensor_dev_attr_in7_min.dev_attr.attr,
345 	&sensor_dev_attr_temp1_input.dev_attr.attr,
346 	&sensor_dev_attr_temp1_max.dev_attr.attr,
347 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
348 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
349 	NULL
350 };
351 
352 static const struct attribute_group adc128_group = {
353 	.attrs = adc128_attrs,
354 	.is_visible = adc128_is_visible,
355 };
356 __ATTRIBUTE_GROUPS(adc128);
357 
358 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
359 {
360 	int man_id, dev_id;
361 
362 	if (!i2c_check_functionality(client->adapter,
363 				     I2C_FUNC_SMBUS_BYTE_DATA |
364 				     I2C_FUNC_SMBUS_WORD_DATA))
365 		return -ENODEV;
366 
367 	man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
368 	dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
369 	if (man_id != 0x01 || dev_id != 0x09)
370 		return -ENODEV;
371 
372 	/* Check unused bits for confirmation */
373 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
374 		return -ENODEV;
375 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
376 		return -ENODEV;
377 	if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
378 		return -ENODEV;
379 	if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
380 		return -ENODEV;
381 	if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
382 		return -ENODEV;
383 	if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
384 		return -ENODEV;
385 
386 	strscpy(info->type, "adc128d818", I2C_NAME_SIZE);
387 
388 	return 0;
389 }
390 
391 static int adc128_init_client(struct adc128_data *data, bool external_vref)
392 {
393 	struct i2c_client *client = data->client;
394 	int err;
395 	u8 regval = 0x0;
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 		regval |= data->mode << 1;
408 
409 	/* If external vref is selected, configure the chip to use it */
410 	if (external_vref)
411 		regval |= 0x01;
412 
413 	/* Write advanced configuration register */
414 	if (regval != 0x0) {
415 		err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG_ADV,
416 						regval);
417 		if (err)
418 			return err;
419 	}
420 
421 	/* Start monitoring */
422 	err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
423 	if (err)
424 		return err;
425 
426 	return 0;
427 }
428 
429 static int adc128_probe(struct i2c_client *client)
430 {
431 	struct device *dev = &client->dev;
432 	struct device *hwmon_dev;
433 	struct adc128_data *data;
434 	bool external_vref;
435 	int err, vref;
436 
437 	data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
438 	if (!data)
439 		return -ENOMEM;
440 
441 	/* vref is optional. If specified, is used as chip reference voltage */
442 	vref = devm_regulator_get_enable_read_voltage(dev, "vref");
443 	if (vref == -ENODEV) {
444 		external_vref = false;
445 		data->vref = 2560;	/* 2.56V, in mV */
446 	} else if (vref < 0) {
447 		return vref;
448 	} else {
449 		external_vref = true;
450 		data->vref = DIV_ROUND_CLOSEST(vref, 1000);
451 	}
452 
453 	/* Operation mode is optional. If unspecified, keep current mode */
454 	if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
455 		if (data->mode > 3) {
456 			dev_err(dev, "invalid operation mode %d\n",
457 				data->mode);
458 			return -EINVAL;
459 		}
460 	} else {
461 		err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
462 		if (err < 0)
463 			return err;
464 		data->mode = (err >> 1) & ADC128_REG_MASK;
465 	}
466 
467 	data->client = client;
468 	i2c_set_clientdata(client, data);
469 	mutex_init(&data->update_lock);
470 
471 	/* Initialize the chip */
472 	err = adc128_init_client(data, external_vref);
473 	if (err < 0)
474 		return err;
475 
476 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
477 							   data, adc128_groups);
478 
479 	return PTR_ERR_OR_ZERO(hwmon_dev);
480 }
481 
482 static const struct i2c_device_id adc128_id[] = {
483 	{ "adc128d818" },
484 	{ }
485 };
486 MODULE_DEVICE_TABLE(i2c, adc128_id);
487 
488 static const struct of_device_id __maybe_unused adc128_of_match[] = {
489 	{ .compatible = "ti,adc128d818" },
490 	{ },
491 };
492 MODULE_DEVICE_TABLE(of, adc128_of_match);
493 
494 static struct i2c_driver adc128_driver = {
495 	.class		= I2C_CLASS_HWMON,
496 	.driver = {
497 		.name	= "adc128d818",
498 		.of_match_table = of_match_ptr(adc128_of_match),
499 	},
500 	.probe		= adc128_probe,
501 	.id_table	= adc128_id,
502 	.detect		= adc128_detect,
503 	.address_list	= normal_i2c,
504 };
505 
506 module_i2c_driver(adc128_driver);
507 
508 MODULE_AUTHOR("Guenter Roeck");
509 MODULE_DESCRIPTION("Driver for ADC128D818");
510 MODULE_LICENSE("GPL");
511