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#include <linux/of.h>
32
33/* Addresses to scan
34 * The chip also supports addresses 0x35..0x37. Don't scan those addresses
35 * since they are also used by some EEPROMs, which may result in false
36 * positives.
37 */
38static const unsigned short normal_i2c[] = {
39 0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
40
41/* registers */
42#define ADC128_REG_IN_MAX(nr) (0x2a + (nr) * 2)
43#define ADC128_REG_IN_MIN(nr) (0x2b + (nr) * 2)
44#define ADC128_REG_IN(nr) (0x20 + (nr))
45
46#define ADC128_REG_TEMP 0x27
47#define ADC128_REG_TEMP_MAX 0x38
48#define ADC128_REG_TEMP_HYST 0x39
49
50#define ADC128_REG_CONFIG 0x00
51#define ADC128_REG_ALARM 0x01
52#define ADC128_REG_MASK 0x03
53#define ADC128_REG_CONV_RATE 0x07
54#define ADC128_REG_ONESHOT 0x09
55#define ADC128_REG_SHUTDOWN 0x0a
56#define ADC128_REG_CONFIG_ADV 0x0b
57#define ADC128_REG_BUSY_STATUS 0x0c
58
59#define ADC128_REG_MAN_ID 0x3e
60#define ADC128_REG_DEV_ID 0x3f
61
62/* No. of voltage entries in adc128_attrs */
63#define ADC128_ATTR_NUM_VOLT (8 * 4)
64
65/* Voltage inputs visible per operation mode */
66static const u8 num_inputs[] = { 7, 8, 4, 6 };
67
68struct adc128_data {
69 struct i2c_client *client;
70 struct regulator *regulator;
71 int vref; /* Reference voltage in mV */
72 struct mutex update_lock;
73 u8 mode; /* Operation mode */
74 bool valid; /* true if following fields are valid */
75 unsigned long last_updated; /* In jiffies */
76
77 u16 in[3][8]; /* Register value, normalized to 12 bit
78 * 0: input voltage
79 * 1: min limit
80 * 2: max limit
81 */
82 s16 temp[3]; /* Register value, normalized to 9 bit
83 * 0: sensor 1: limit 2: hyst
84 */
85 u8 alarms; /* alarm register value */
86};
87
88static struct adc128_data *adc128_update_device(struct device *dev)
89{
90 struct adc128_data *data = dev_get_drvdata(dev);
91 struct i2c_client *client = data->client;
92 struct adc128_data *ret = data;
93 int i, rv;
94
95 mutex_lock(&data->update_lock);
96
97 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
98 for (i = 0; i < num_inputs[data->mode]; i++) {
99 rv = i2c_smbus_read_word_swapped(client,
100 ADC128_REG_IN(i));
101 if (rv < 0)
102 goto abort;
103 data->in[0][i] = rv >> 4;
104
105 rv = i2c_smbus_read_byte_data(client,
106 ADC128_REG_IN_MIN(i));
107 if (rv < 0)
108 goto abort;
109 data->in[1][i] = rv << 4;
110
111 rv = i2c_smbus_read_byte_data(client,
112 ADC128_REG_IN_MAX(i));
113 if (rv < 0)
114 goto abort;
115 data->in[2][i] = rv << 4;
116 }
117
118 if (data->mode != 1) {
119 rv = i2c_smbus_read_word_swapped(client,
120 ADC128_REG_TEMP);
121 if (rv < 0)
122 goto abort;
123 data->temp[0] = rv >> 7;
124
125 rv = i2c_smbus_read_byte_data(client,
126 ADC128_REG_TEMP_MAX);
127 if (rv < 0)
128 goto abort;
129 data->temp[1] = rv << 1;
130
131 rv = i2c_smbus_read_byte_data(client,
132 ADC128_REG_TEMP_HYST);
133 if (rv < 0)
134 goto abort;
135 data->temp[2] = rv << 1;
136 }
137
138 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
139 if (rv < 0)
140 goto abort;
141 data->alarms |= rv;
142
143 data->last_updated = jiffies;
144 data->valid = true;
145 }
146 goto done;
147
148abort:
149 ret = ERR_PTR(rv);
150 data->valid = false;
151done:
152 mutex_unlock(&data->update_lock);
153 return ret;
154}
155
156static ssize_t adc128_in_show(struct device *dev,
157 struct device_attribute *attr, char *buf)
158{
159 struct adc128_data *data = adc128_update_device(dev);
160 int index = to_sensor_dev_attr_2(attr)->index;
161 int nr = to_sensor_dev_attr_2(attr)->nr;
162 int val;
163
164 if (IS_ERR(data))
165 return PTR_ERR(data);
166
167 val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
168 return sprintf(buf, "%d\n", val);
169}
170
171static ssize_t adc128_in_store(struct device *dev,
172 struct device_attribute *attr, const char *buf,
173 size_t count)
174{
175 struct adc128_data *data = dev_get_drvdata(dev);
176 int index = to_sensor_dev_attr_2(attr)->index;
177 int nr = to_sensor_dev_attr_2(attr)->nr;
178 u8 reg, regval;
179 long val;
180 int err;
181
182 err = kstrtol(buf, 10, &val);
183 if (err < 0)
184 return err;
185
186 mutex_lock(&data->update_lock);
187 /* 10 mV LSB on limit registers */
188 regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
189 data->in[index][nr] = regval << 4;
190 reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
191 i2c_smbus_write_byte_data(data->client, reg, regval);
192 mutex_unlock(&data->update_lock);
193
194 return count;
195}
196
197static ssize_t adc128_temp_show(struct device *dev,
198 struct device_attribute *attr, char *buf)
199{
200 struct adc128_data *data = adc128_update_device(dev);
201 int index = to_sensor_dev_attr(attr)->index;
202 int temp;
203
204 if (IS_ERR(data))
205 return PTR_ERR(data);
206
207 temp = sign_extend32(data->temp[index], 8);
208 return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
209}
210
211static ssize_t adc128_temp_store(struct device *dev,
212 struct device_attribute *attr,
213 const char *buf, size_t count)
214{
215 struct adc128_data *data = dev_get_drvdata(dev);
216 int index = to_sensor_dev_attr(attr)->index;
217 long val;
218 int err;
219 s8 regval;
220
221 err = kstrtol(buf, 10, &val);
222 if (err < 0)
223 return err;
224
225 mutex_lock(&data->update_lock);
226 regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
227 data->temp[index] = regval << 1;
228 i2c_smbus_write_byte_data(data->client,
229 index == 1 ? ADC128_REG_TEMP_MAX
230 : ADC128_REG_TEMP_HYST,
231 regval);
232 mutex_unlock(&data->update_lock);
233
234 return count;
235}
236
237static ssize_t adc128_alarm_show(struct device *dev,
238 struct device_attribute *attr, char *buf)
239{
240 struct adc128_data *data = adc128_update_device(dev);
241 int mask = 1 << to_sensor_dev_attr(attr)->index;
242 u8 alarms;
243
244 if (IS_ERR(data))
245 return PTR_ERR(data);
246
247 /*
248 * Clear an alarm after reporting it to user space. If it is still
249 * active, the next update sequence will set the alarm bit again.
250 */
251 alarms = data->alarms;
252 data->alarms &= ~mask;
253
254 return sprintf(buf, "%u\n", !!(alarms & mask));
255}
256
257static umode_t adc128_is_visible(struct kobject *kobj,
258 struct attribute *attr, int index)
259{
260 struct device *dev = container_of(kobj, struct device, kobj);
261 struct adc128_data *data = dev_get_drvdata(dev);
262
263 if (index < ADC128_ATTR_NUM_VOLT) {
264 /* Voltage, visible according to num_inputs[] */
265 if (index >= num_inputs[data->mode] * 4)
266 return 0;
267 } else {
268 /* Temperature, visible if not in mode 1 */
269 if (data->mode == 1)
270 return 0;
271 }
272
273 return attr->mode;
274}
275
276static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
277static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
278static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
279
280static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
281static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
282static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
283
284static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
285static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
286static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
287
288static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
289static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
290static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
291
292static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
293static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
294static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
295
296static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
297static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
298static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
299
300static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
301static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
302static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
303
304static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
305static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
306static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
307
308static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
309static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
310static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
311
312static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
313static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
314static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
315static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
316static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
317static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
318static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
319static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
320static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
321
322static struct attribute *adc128_attrs[] = {
323 &sensor_dev_attr_in0_alarm.dev_attr.attr,
324 &sensor_dev_attr_in0_input.dev_attr.attr,
325 &sensor_dev_attr_in0_max.dev_attr.attr,
326 &sensor_dev_attr_in0_min.dev_attr.attr,
327 &sensor_dev_attr_in1_alarm.dev_attr.attr,
328 &sensor_dev_attr_in1_input.dev_attr.attr,
329 &sensor_dev_attr_in1_max.dev_attr.attr,
330 &sensor_dev_attr_in1_min.dev_attr.attr,
331 &sensor_dev_attr_in2_alarm.dev_attr.attr,
332 &sensor_dev_attr_in2_input.dev_attr.attr,
333 &sensor_dev_attr_in2_max.dev_attr.attr,
334 &sensor_dev_attr_in2_min.dev_attr.attr,
335 &sensor_dev_attr_in3_alarm.dev_attr.attr,
336 &sensor_dev_attr_in3_input.dev_attr.attr,
337 &sensor_dev_attr_in3_max.dev_attr.attr,
338 &sensor_dev_attr_in3_min.dev_attr.attr,
339 &sensor_dev_attr_in4_alarm.dev_attr.attr,
340 &sensor_dev_attr_in4_input.dev_attr.attr,
341 &sensor_dev_attr_in4_max.dev_attr.attr,
342 &sensor_dev_attr_in4_min.dev_attr.attr,
343 &sensor_dev_attr_in5_alarm.dev_attr.attr,
344 &sensor_dev_attr_in5_input.dev_attr.attr,
345 &sensor_dev_attr_in5_max.dev_attr.attr,
346 &sensor_dev_attr_in5_min.dev_attr.attr,
347 &sensor_dev_attr_in6_alarm.dev_attr.attr,
348 &sensor_dev_attr_in6_input.dev_attr.attr,
349 &sensor_dev_attr_in6_max.dev_attr.attr,
350 &sensor_dev_attr_in6_min.dev_attr.attr,
351 &sensor_dev_attr_in7_alarm.dev_attr.attr,
352 &sensor_dev_attr_in7_input.dev_attr.attr,
353 &sensor_dev_attr_in7_max.dev_attr.attr,
354 &sensor_dev_attr_in7_min.dev_attr.attr,
355 &sensor_dev_attr_temp1_input.dev_attr.attr,
356 &sensor_dev_attr_temp1_max.dev_attr.attr,
357 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
358 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
359 NULL
360};
361
362static const struct attribute_group adc128_group = {
363 .attrs = adc128_attrs,
364 .is_visible = adc128_is_visible,
365};
366__ATTRIBUTE_GROUPS(adc128);
367
368static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
369{
370 int man_id, dev_id;
371
372 if (!i2c_check_functionality(client->adapter,
373 I2C_FUNC_SMBUS_BYTE_DATA |
374 I2C_FUNC_SMBUS_WORD_DATA))
375 return -ENODEV;
376
377 man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
378 dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
379 if (man_id != 0x01 || dev_id != 0x09)
380 return -ENODEV;
381
382 /* Check unused bits for confirmation */
383 if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
384 return -ENODEV;
385 if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
386 return -ENODEV;
387 if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
388 return -ENODEV;
389 if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
390 return -ENODEV;
391 if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
392 return -ENODEV;
393 if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
394 return -ENODEV;
395
396 strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
397
398 return 0;
399}
400
401static int adc128_init_client(struct adc128_data *data)
402{
403 struct i2c_client *client = data->client;
404 int err;
405
406 /*
407 * Reset chip to defaults.
408 * This makes most other initializations unnecessary.
409 */
410 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
411 if (err)
412 return err;
413
414 /* Set operation mode, if non-default */
415 if (data->mode != 0) {
416 err = i2c_smbus_write_byte_data(client,
417 ADC128_REG_CONFIG_ADV,
418 data->mode << 1);
419 if (err)
420 return err;
421 }
422
423 /* Start monitoring */
424 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
425 if (err)
426 return err;
427
428 /* If external vref is selected, configure the chip to use it */
429 if (data->regulator) {
430 err = i2c_smbus_write_byte_data(client,
431 ADC128_REG_CONFIG_ADV, 0x01);
432 if (err)
433 return err;
434 }
435
436 return 0;
437}
438
439static int adc128_probe(struct i2c_client *client,
440 const struct i2c_device_id *id)
441{
442 struct device *dev = &client->dev;
443 struct regulator *regulator;
444 struct device *hwmon_dev;
445 struct adc128_data *data;
446 int err, vref;
447
448 data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
449 if (!data)
450 return -ENOMEM;
451
452 /* vref is optional. If specified, is used as chip reference voltage */
453 regulator = devm_regulator_get_optional(dev, "vref");
454 if (!IS_ERR(regulator)) {
455 data->regulator = regulator;
456 err = regulator_enable(regulator);
457 if (err < 0)
458 return err;
459 vref = regulator_get_voltage(regulator);
460 if (vref < 0) {
461 err = vref;
462 goto error;
463 }
464 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
465 } else {
466 data->vref = 2560; /* 2.56V, in mV */
467 }
468
469 /* Operation mode is optional. If unspecified, keep current mode */
470 if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
471 if (data->mode > 3) {
472 dev_err(dev, "invalid operation mode %d\n",
473 data->mode);
474 err = -EINVAL;
475 goto error;
476 }
477 } else {
478 err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
479 if (err < 0)
480 goto error;
481 data->mode = (err >> 1) & ADC128_REG_MASK;
482 }
483
484 data->client = client;
485 i2c_set_clientdata(client, data);
486 mutex_init(&data->update_lock);
487
488 /* Initialize the chip */
489 err = adc128_init_client(data);
490 if (err < 0)
491 goto error;
492
493 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
494 data, adc128_groups);
495 if (IS_ERR(hwmon_dev)) {
496 err = PTR_ERR(hwmon_dev);
497 goto error;
498 }
499
500 return 0;
501
502error:
503 if (data->regulator)
504 regulator_disable(data->regulator);
505 return err;
506}
507
508static int adc128_remove(struct i2c_client *client)
509{
510 struct adc128_data *data = i2c_get_clientdata(client);
511
512 if (data->regulator)
513 regulator_disable(data->regulator);
514
515 return 0;
516}
517
518static const struct i2c_device_id adc128_id[] = {
519 { "adc128d818", 0 },
520 { }
521};
522MODULE_DEVICE_TABLE(i2c, adc128_id);
523
524static const struct of_device_id adc128_of_match[] = {
525 { .compatible = "ti,adc128d818" },
526 { },
527};
528MODULE_DEVICE_TABLE(of, adc128_of_match);
529
530static struct i2c_driver adc128_driver = {
531 .class = I2C_CLASS_HWMON,
532 .driver = {
533 .name = "adc128d818",
534 .of_match_table = of_match_ptr(adc128_of_match),
535 },
536 .probe = adc128_probe,
537 .remove = adc128_remove,
538 .id_table = adc128_id,
539 .detect = adc128_detect,
540 .address_list = normal_i2c,
541};
542
543module_i2c_driver(adc128_driver);
544
545MODULE_AUTHOR("Guenter Roeck");
546MODULE_DESCRIPTION("Driver for ADC128D818");
547MODULE_LICENSE("GPL");
548