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
adc128_update_device(struct device * dev)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
adc128_in_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_in_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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
adc128_temp_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_temp_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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
adc128_alarm_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_is_visible(struct kobject * kobj,struct attribute * attr,int index)248 static umode_t adc128_is_visible(struct kobject *kobj,
249 struct attribute *attr, int index)
250 {
251 struct device *dev = kobj_to_dev(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
adc128_detect(struct i2c_client * client,struct i2c_board_info * info)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 strscpy(info->type, "adc128d818", I2C_NAME_SIZE);
388
389 return 0;
390 }
391
adc128_init_client(struct adc128_data * data)392 static int adc128_init_client(struct adc128_data *data)
393 {
394 struct i2c_client *client = data->client;
395 int err;
396 u8 regval = 0x0;
397
398 /*
399 * Reset chip to defaults.
400 * This makes most other initializations unnecessary.
401 */
402 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
403 if (err)
404 return err;
405
406 /* Set operation mode, if non-default */
407 if (data->mode != 0)
408 regval |= data->mode << 1;
409
410 /* If external vref is selected, configure the chip to use it */
411 if (data->regulator)
412 regval |= 0x01;
413
414 /* Write advanced configuration register */
415 if (regval != 0x0) {
416 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG_ADV,
417 regval);
418 if (err)
419 return err;
420 }
421
422 /* Start monitoring */
423 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
424 if (err)
425 return err;
426
427 return 0;
428 }
429
adc128_probe(struct i2c_client * client)430 static int adc128_probe(struct i2c_client *client)
431 {
432 struct device *dev = &client->dev;
433 struct regulator *regulator;
434 struct device *hwmon_dev;
435 struct adc128_data *data;
436 int err, vref;
437
438 data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
439 if (!data)
440 return -ENOMEM;
441
442 /* vref is optional. If specified, is used as chip reference voltage */
443 regulator = devm_regulator_get_optional(dev, "vref");
444 if (!IS_ERR(regulator)) {
445 data->regulator = regulator;
446 err = regulator_enable(regulator);
447 if (err < 0)
448 return err;
449 vref = regulator_get_voltage(regulator);
450 if (vref < 0) {
451 err = vref;
452 goto error;
453 }
454 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
455 } else {
456 data->vref = 2560; /* 2.56V, in mV */
457 }
458
459 /* Operation mode is optional. If unspecified, keep current mode */
460 if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
461 if (data->mode > 3) {
462 dev_err(dev, "invalid operation mode %d\n",
463 data->mode);
464 err = -EINVAL;
465 goto error;
466 }
467 } else {
468 err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
469 if (err < 0)
470 goto error;
471 data->mode = (err >> 1) & ADC128_REG_MASK;
472 }
473
474 data->client = client;
475 i2c_set_clientdata(client, data);
476 mutex_init(&data->update_lock);
477
478 /* Initialize the chip */
479 err = adc128_init_client(data);
480 if (err < 0)
481 goto error;
482
483 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
484 data, adc128_groups);
485 if (IS_ERR(hwmon_dev)) {
486 err = PTR_ERR(hwmon_dev);
487 goto error;
488 }
489
490 return 0;
491
492 error:
493 if (data->regulator)
494 regulator_disable(data->regulator);
495 return err;
496 }
497
adc128_remove(struct i2c_client * client)498 static void adc128_remove(struct i2c_client *client)
499 {
500 struct adc128_data *data = i2c_get_clientdata(client);
501
502 if (data->regulator)
503 regulator_disable(data->regulator);
504 }
505
506 static const struct i2c_device_id adc128_id[] = {
507 { "adc128d818", 0 },
508 { }
509 };
510 MODULE_DEVICE_TABLE(i2c, adc128_id);
511
512 static const struct of_device_id __maybe_unused adc128_of_match[] = {
513 { .compatible = "ti,adc128d818" },
514 { },
515 };
516 MODULE_DEVICE_TABLE(of, adc128_of_match);
517
518 static struct i2c_driver adc128_driver = {
519 .class = I2C_CLASS_HWMON,
520 .driver = {
521 .name = "adc128d818",
522 .of_match_table = of_match_ptr(adc128_of_match),
523 },
524 .probe = adc128_probe,
525 .remove = adc128_remove,
526 .id_table = adc128_id,
527 .detect = adc128_detect,
528 .address_list = normal_i2c,
529 };
530
531 module_i2c_driver(adc128_driver);
532
533 MODULE_AUTHOR("Guenter Roeck");
534 MODULE_DESCRIPTION("Driver for ADC128D818");
535 MODULE_LICENSE("GPL");
536