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
adc128_update_device(struct device * dev)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
adc128_in_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_in_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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
adc128_temp_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_temp_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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
adc128_alarm_show(struct device * dev,struct device_attribute * attr,char * buf)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
adc128_is_visible(struct kobject * kobj,struct attribute * attr,int index)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
adc128_detect(struct i2c_client * client,struct i2c_board_info * info)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
adc128_init_client(struct adc128_data * data,bool external_vref)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
adc128_probe(struct i2c_client * client)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