1 // SPDX-License-Identifier: GPL-2.0-only
3 * Driver for SMM665 Power Controller / Monitor
5 * Copyright (C) 2010 Ericsson AB.
7 * This driver should also work for SMM465, SMM764, and SMM766, but is untested
8 * for those chips. Only monitoring functionality is implemented.
11 * http://www.summitmicro.com/prod_select/summary/SMM665/SMM665B_2089_20.pdf
12 * http://www.summitmicro.com/prod_select/summary/SMM766B/SMM766B_2122.pdf
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/i2c.h>
21 #include <linux/hwmon.h>
22 #include <linux/hwmon-sysfs.h>
23 #include <linux/delay.h>
24 #include <linux/jiffies.h>
26 /* Internal reference voltage (VREF, x 1000 */
27 #define SMM665_VREF_ADC_X1000 1250
29 /* module parameters */
30 static int vref = SMM665_VREF_ADC_X1000;
31 module_param(vref, int, 0);
32 MODULE_PARM_DESC(vref, "Reference voltage in mV");
34 enum chips { smm465, smm665, smm665c, smm764, smm766 };
37 * ADC channel addresses
39 #define SMM665_MISC16_ADC_DATA_A 0x00
40 #define SMM665_MISC16_ADC_DATA_B 0x01
41 #define SMM665_MISC16_ADC_DATA_C 0x02
42 #define SMM665_MISC16_ADC_DATA_D 0x03
43 #define SMM665_MISC16_ADC_DATA_E 0x04
44 #define SMM665_MISC16_ADC_DATA_F 0x05
45 #define SMM665_MISC16_ADC_DATA_VDD 0x06
46 #define SMM665_MISC16_ADC_DATA_12V 0x07
47 #define SMM665_MISC16_ADC_DATA_INT_TEMP 0x08
48 #define SMM665_MISC16_ADC_DATA_AIN1 0x09
49 #define SMM665_MISC16_ADC_DATA_AIN2 0x0a
54 #define SMM665_MISC8_CMD_STS 0x80
55 #define SMM665_MISC8_STATUS1 0x81
56 #define SMM665_MISC8_STATUSS2 0x82
57 #define SMM665_MISC8_IO_POLARITY 0x83
58 #define SMM665_MISC8_PUP_POLARITY 0x84
59 #define SMM665_MISC8_ADOC_STATUS1 0x85
60 #define SMM665_MISC8_ADOC_STATUS2 0x86
61 #define SMM665_MISC8_WRITE_PROT 0x87
62 #define SMM665_MISC8_STS_TRACK 0x88
65 * Configuration registers and register groups
67 #define SMM665_ADOC_ENABLE 0x0d
68 #define SMM665_LIMIT_BASE 0x80 /* First limit register */
71 * Limit register bit masks
73 #define SMM665_TRIGGER_RST 0x8000
74 #define SMM665_TRIGGER_HEALTHY 0x4000
75 #define SMM665_TRIGGER_POWEROFF 0x2000
76 #define SMM665_TRIGGER_SHUTDOWN 0x1000
77 #define SMM665_ADC_MASK 0x03ff
79 #define smm665_is_critical(lim) ((lim) & (SMM665_TRIGGER_RST \
80 | SMM665_TRIGGER_POWEROFF \
81 | SMM665_TRIGGER_SHUTDOWN))
83 * Fault register bit definitions
84 * Values are merged from status registers 1/2,
85 * with status register 1 providing the upper 8 bits.
87 #define SMM665_FAULT_A 0x0001
88 #define SMM665_FAULT_B 0x0002
89 #define SMM665_FAULT_C 0x0004
90 #define SMM665_FAULT_D 0x0008
91 #define SMM665_FAULT_E 0x0010
92 #define SMM665_FAULT_F 0x0020
93 #define SMM665_FAULT_VDD 0x0040
94 #define SMM665_FAULT_12V 0x0080
95 #define SMM665_FAULT_TEMP 0x0100
96 #define SMM665_FAULT_AIN1 0x0200
97 #define SMM665_FAULT_AIN2 0x0400
100 * I2C Register addresses
102 * The configuration register needs to be the configured base register.
103 * The command/status register address is derived from it.
105 #define SMM665_REGMASK 0x78
106 #define SMM665_CMDREG_BASE 0x48
107 #define SMM665_CONFREG_BASE 0x50
110 * Equations given by chip manufacturer to calculate voltage/temperature values
111 * vref = Reference voltage on VREF_ADC pin (module parameter)
112 * adc = 10bit ADC value read back from registers
115 /* Voltage A-F and VDD */
116 #define SMM665_VMON_ADC_TO_VOLTS(adc) ((adc) * vref / 256)
119 #define SMM665_12VIN_ADC_TO_VOLTS(adc) ((adc) * vref * 3 / 256)
121 /* Voltage AIN1, AIN2 */
122 #define SMM665_AIN_ADC_TO_VOLTS(adc) ((adc) * vref / 512)
125 #define SMM665_TEMP_ADC_TO_CELSIUS(adc) (((adc) <= 511) ? \
126 ((int)(adc) * 1000 / 4) : \
127 (((int)(adc) - 0x400) * 1000 / 4))
129 #define SMM665_NUM_ADC 11
132 * Chip dependent ADC conversion time, in uS
134 #define SMM665_ADC_WAIT_SMM665 70
135 #define SMM665_ADC_WAIT_SMM766 185
139 int conversion_time; /* ADC conversion time */
140 struct i2c_client *client;
141 struct mutex update_lock;
143 unsigned long last_updated; /* in jiffies */
144 u16 adc[SMM665_NUM_ADC]; /* adc values (raw) */
145 u16 faults; /* fault status */
146 /* The following values are in mV */
147 int critical_min_limit[SMM665_NUM_ADC];
148 int alarm_min_limit[SMM665_NUM_ADC];
149 int critical_max_limit[SMM665_NUM_ADC];
150 int alarm_max_limit[SMM665_NUM_ADC];
151 struct i2c_client *cmdreg;
157 * Read 16 bit value from <reg>, <reg+1>. Upper 8 bits are in <reg>.
159 static int smm665_read16(struct i2c_client *client, int reg)
163 rv = i2c_smbus_read_byte_data(client, reg);
167 rv = i2c_smbus_read_byte_data(client, reg + 1);
177 static int smm665_read_adc(struct smm665_data *data, int adc)
179 struct i2c_client *client = data->cmdreg;
184 * Algorithm for reading ADC, per SMM665 datasheet
186 * {[S][addr][W][Ack]} {[offset][Ack]} {[S][addr][R][Nack]}
187 * [wait conversion time]
188 * {[S][addr][R][Ack]} {[datahi][Ack]} {[datalo][Ack][P]}
190 * To implement the first part of this exchange,
191 * do a full read transaction and expect a failure/Nack.
192 * This sets up the address pointer on the SMM665
193 * and starts the ADC conversion.
194 * Then do a two-byte read transaction.
196 rv = i2c_smbus_read_byte_data(client, adc << 3);
199 * We expect ENXIO to reflect NACK
200 * (per Documentation/i2c/fault-codes.rst).
201 * Everything else is an error.
203 dev_dbg(&client->dev,
204 "Unexpected return code %d when setting ADC index", rv);
205 return (rv < 0) ? rv : -EIO;
208 udelay(data->conversion_time);
211 * Now read two bytes.
213 * Neither i2c_smbus_read_byte() nor
214 * i2c_smbus_read_block_data() worked here,
215 * so use i2c_smbus_read_word_swapped() instead.
216 * We could also try to use i2c_master_recv(),
217 * but that is not always supported.
219 rv = i2c_smbus_read_word_swapped(client, 0);
221 dev_dbg(&client->dev, "Failed to read ADC value: error %d", rv);
225 * Validate/verify readback adc channel (in bit 11..14).
227 radc = (rv >> 11) & 0x0f;
229 dev_dbg(&client->dev, "Unexpected RADC: Expected %d got %d",
234 return rv & SMM665_ADC_MASK;
237 static struct smm665_data *smm665_update_device(struct device *dev)
239 struct smm665_data *data = dev_get_drvdata(dev);
240 struct i2c_client *client = data->client;
241 struct smm665_data *ret = data;
243 mutex_lock(&data->update_lock);
245 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
249 * read status registers
251 val = smm665_read16(client, SMM665_MISC8_STATUS1);
252 if (unlikely(val < 0)) {
258 /* Read adc registers */
259 for (i = 0; i < SMM665_NUM_ADC; i++) {
260 val = smm665_read_adc(data, i);
261 if (unlikely(val < 0)) {
267 data->last_updated = jiffies;
271 mutex_unlock(&data->update_lock);
275 /* Return converted value from given adc */
276 static int smm665_convert(u16 adcval, int index)
281 case SMM665_MISC16_ADC_DATA_12V:
282 val = SMM665_12VIN_ADC_TO_VOLTS(adcval & SMM665_ADC_MASK);
285 case SMM665_MISC16_ADC_DATA_VDD:
286 case SMM665_MISC16_ADC_DATA_A:
287 case SMM665_MISC16_ADC_DATA_B:
288 case SMM665_MISC16_ADC_DATA_C:
289 case SMM665_MISC16_ADC_DATA_D:
290 case SMM665_MISC16_ADC_DATA_E:
291 case SMM665_MISC16_ADC_DATA_F:
292 val = SMM665_VMON_ADC_TO_VOLTS(adcval & SMM665_ADC_MASK);
295 case SMM665_MISC16_ADC_DATA_AIN1:
296 case SMM665_MISC16_ADC_DATA_AIN2:
297 val = SMM665_AIN_ADC_TO_VOLTS(adcval & SMM665_ADC_MASK);
300 case SMM665_MISC16_ADC_DATA_INT_TEMP:
301 val = SMM665_TEMP_ADC_TO_CELSIUS(adcval & SMM665_ADC_MASK);
305 /* If we get here, the developer messed up */
313 static int smm665_get_min(struct device *dev, int index)
315 struct smm665_data *data = dev_get_drvdata(dev);
317 return data->alarm_min_limit[index];
320 static int smm665_get_max(struct device *dev, int index)
322 struct smm665_data *data = dev_get_drvdata(dev);
324 return data->alarm_max_limit[index];
327 static int smm665_get_lcrit(struct device *dev, int index)
329 struct smm665_data *data = dev_get_drvdata(dev);
331 return data->critical_min_limit[index];
334 static int smm665_get_crit(struct device *dev, int index)
336 struct smm665_data *data = dev_get_drvdata(dev);
338 return data->critical_max_limit[index];
341 static ssize_t smm665_show_crit_alarm(struct device *dev,
342 struct device_attribute *da, char *buf)
344 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
345 struct smm665_data *data = smm665_update_device(dev);
349 return PTR_ERR(data);
351 if (data->faults & (1 << attr->index))
354 return sysfs_emit(buf, "%d\n", val);
357 static ssize_t smm665_show_input(struct device *dev,
358 struct device_attribute *da, char *buf)
360 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
361 struct smm665_data *data = smm665_update_device(dev);
362 int adc = attr->index;
366 return PTR_ERR(data);
368 val = smm665_convert(data->adc[adc], adc);
369 return sysfs_emit(buf, "%d\n", val);
372 #define SMM665_SHOW(what) \
373 static ssize_t smm665_show_##what(struct device *dev, \
374 struct device_attribute *da, char *buf) \
376 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); \
377 const int val = smm665_get_##what(dev, attr->index); \
378 return snprintf(buf, PAGE_SIZE, "%d\n", val); \
387 * These macros are used below in constructing device attribute objects
388 * for use with sysfs_create_group() to make a sysfs device file
392 #define SMM665_ATTR(name, type, cmd_idx) \
393 static SENSOR_DEVICE_ATTR(name##_##type, S_IRUGO, \
394 smm665_show_##type, NULL, cmd_idx)
396 /* Construct a sensor_device_attribute structure for each register */
399 SMM665_ATTR(in1, input, SMM665_MISC16_ADC_DATA_12V);
400 SMM665_ATTR(in2, input, SMM665_MISC16_ADC_DATA_VDD);
401 SMM665_ATTR(in3, input, SMM665_MISC16_ADC_DATA_A);
402 SMM665_ATTR(in4, input, SMM665_MISC16_ADC_DATA_B);
403 SMM665_ATTR(in5, input, SMM665_MISC16_ADC_DATA_C);
404 SMM665_ATTR(in6, input, SMM665_MISC16_ADC_DATA_D);
405 SMM665_ATTR(in7, input, SMM665_MISC16_ADC_DATA_E);
406 SMM665_ATTR(in8, input, SMM665_MISC16_ADC_DATA_F);
407 SMM665_ATTR(in9, input, SMM665_MISC16_ADC_DATA_AIN1);
408 SMM665_ATTR(in10, input, SMM665_MISC16_ADC_DATA_AIN2);
410 /* Input voltages min */
411 SMM665_ATTR(in1, min, SMM665_MISC16_ADC_DATA_12V);
412 SMM665_ATTR(in2, min, SMM665_MISC16_ADC_DATA_VDD);
413 SMM665_ATTR(in3, min, SMM665_MISC16_ADC_DATA_A);
414 SMM665_ATTR(in4, min, SMM665_MISC16_ADC_DATA_B);
415 SMM665_ATTR(in5, min, SMM665_MISC16_ADC_DATA_C);
416 SMM665_ATTR(in6, min, SMM665_MISC16_ADC_DATA_D);
417 SMM665_ATTR(in7, min, SMM665_MISC16_ADC_DATA_E);
418 SMM665_ATTR(in8, min, SMM665_MISC16_ADC_DATA_F);
419 SMM665_ATTR(in9, min, SMM665_MISC16_ADC_DATA_AIN1);
420 SMM665_ATTR(in10, min, SMM665_MISC16_ADC_DATA_AIN2);
422 /* Input voltages max */
423 SMM665_ATTR(in1, max, SMM665_MISC16_ADC_DATA_12V);
424 SMM665_ATTR(in2, max, SMM665_MISC16_ADC_DATA_VDD);
425 SMM665_ATTR(in3, max, SMM665_MISC16_ADC_DATA_A);
426 SMM665_ATTR(in4, max, SMM665_MISC16_ADC_DATA_B);
427 SMM665_ATTR(in5, max, SMM665_MISC16_ADC_DATA_C);
428 SMM665_ATTR(in6, max, SMM665_MISC16_ADC_DATA_D);
429 SMM665_ATTR(in7, max, SMM665_MISC16_ADC_DATA_E);
430 SMM665_ATTR(in8, max, SMM665_MISC16_ADC_DATA_F);
431 SMM665_ATTR(in9, max, SMM665_MISC16_ADC_DATA_AIN1);
432 SMM665_ATTR(in10, max, SMM665_MISC16_ADC_DATA_AIN2);
434 /* Input voltages lcrit */
435 SMM665_ATTR(in1, lcrit, SMM665_MISC16_ADC_DATA_12V);
436 SMM665_ATTR(in2, lcrit, SMM665_MISC16_ADC_DATA_VDD);
437 SMM665_ATTR(in3, lcrit, SMM665_MISC16_ADC_DATA_A);
438 SMM665_ATTR(in4, lcrit, SMM665_MISC16_ADC_DATA_B);
439 SMM665_ATTR(in5, lcrit, SMM665_MISC16_ADC_DATA_C);
440 SMM665_ATTR(in6, lcrit, SMM665_MISC16_ADC_DATA_D);
441 SMM665_ATTR(in7, lcrit, SMM665_MISC16_ADC_DATA_E);
442 SMM665_ATTR(in8, lcrit, SMM665_MISC16_ADC_DATA_F);
443 SMM665_ATTR(in9, lcrit, SMM665_MISC16_ADC_DATA_AIN1);
444 SMM665_ATTR(in10, lcrit, SMM665_MISC16_ADC_DATA_AIN2);
446 /* Input voltages crit */
447 SMM665_ATTR(in1, crit, SMM665_MISC16_ADC_DATA_12V);
448 SMM665_ATTR(in2, crit, SMM665_MISC16_ADC_DATA_VDD);
449 SMM665_ATTR(in3, crit, SMM665_MISC16_ADC_DATA_A);
450 SMM665_ATTR(in4, crit, SMM665_MISC16_ADC_DATA_B);
451 SMM665_ATTR(in5, crit, SMM665_MISC16_ADC_DATA_C);
452 SMM665_ATTR(in6, crit, SMM665_MISC16_ADC_DATA_D);
453 SMM665_ATTR(in7, crit, SMM665_MISC16_ADC_DATA_E);
454 SMM665_ATTR(in8, crit, SMM665_MISC16_ADC_DATA_F);
455 SMM665_ATTR(in9, crit, SMM665_MISC16_ADC_DATA_AIN1);
456 SMM665_ATTR(in10, crit, SMM665_MISC16_ADC_DATA_AIN2);
458 /* critical alarms */
459 SMM665_ATTR(in1, crit_alarm, SMM665_FAULT_12V);
460 SMM665_ATTR(in2, crit_alarm, SMM665_FAULT_VDD);
461 SMM665_ATTR(in3, crit_alarm, SMM665_FAULT_A);
462 SMM665_ATTR(in4, crit_alarm, SMM665_FAULT_B);
463 SMM665_ATTR(in5, crit_alarm, SMM665_FAULT_C);
464 SMM665_ATTR(in6, crit_alarm, SMM665_FAULT_D);
465 SMM665_ATTR(in7, crit_alarm, SMM665_FAULT_E);
466 SMM665_ATTR(in8, crit_alarm, SMM665_FAULT_F);
467 SMM665_ATTR(in9, crit_alarm, SMM665_FAULT_AIN1);
468 SMM665_ATTR(in10, crit_alarm, SMM665_FAULT_AIN2);
471 SMM665_ATTR(temp1, input, SMM665_MISC16_ADC_DATA_INT_TEMP);
472 SMM665_ATTR(temp1, min, SMM665_MISC16_ADC_DATA_INT_TEMP);
473 SMM665_ATTR(temp1, max, SMM665_MISC16_ADC_DATA_INT_TEMP);
474 SMM665_ATTR(temp1, lcrit, SMM665_MISC16_ADC_DATA_INT_TEMP);
475 SMM665_ATTR(temp1, crit, SMM665_MISC16_ADC_DATA_INT_TEMP);
476 SMM665_ATTR(temp1, crit_alarm, SMM665_FAULT_TEMP);
479 * Finally, construct an array of pointers to members of the above objects,
480 * as required for sysfs_create_group()
482 static struct attribute *smm665_attrs[] = {
483 &sensor_dev_attr_in1_input.dev_attr.attr,
484 &sensor_dev_attr_in1_min.dev_attr.attr,
485 &sensor_dev_attr_in1_max.dev_attr.attr,
486 &sensor_dev_attr_in1_lcrit.dev_attr.attr,
487 &sensor_dev_attr_in1_crit.dev_attr.attr,
488 &sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
490 &sensor_dev_attr_in2_input.dev_attr.attr,
491 &sensor_dev_attr_in2_min.dev_attr.attr,
492 &sensor_dev_attr_in2_max.dev_attr.attr,
493 &sensor_dev_attr_in2_lcrit.dev_attr.attr,
494 &sensor_dev_attr_in2_crit.dev_attr.attr,
495 &sensor_dev_attr_in2_crit_alarm.dev_attr.attr,
497 &sensor_dev_attr_in3_input.dev_attr.attr,
498 &sensor_dev_attr_in3_min.dev_attr.attr,
499 &sensor_dev_attr_in3_max.dev_attr.attr,
500 &sensor_dev_attr_in3_lcrit.dev_attr.attr,
501 &sensor_dev_attr_in3_crit.dev_attr.attr,
502 &sensor_dev_attr_in3_crit_alarm.dev_attr.attr,
504 &sensor_dev_attr_in4_input.dev_attr.attr,
505 &sensor_dev_attr_in4_min.dev_attr.attr,
506 &sensor_dev_attr_in4_max.dev_attr.attr,
507 &sensor_dev_attr_in4_lcrit.dev_attr.attr,
508 &sensor_dev_attr_in4_crit.dev_attr.attr,
509 &sensor_dev_attr_in4_crit_alarm.dev_attr.attr,
511 &sensor_dev_attr_in5_input.dev_attr.attr,
512 &sensor_dev_attr_in5_min.dev_attr.attr,
513 &sensor_dev_attr_in5_max.dev_attr.attr,
514 &sensor_dev_attr_in5_lcrit.dev_attr.attr,
515 &sensor_dev_attr_in5_crit.dev_attr.attr,
516 &sensor_dev_attr_in5_crit_alarm.dev_attr.attr,
518 &sensor_dev_attr_in6_input.dev_attr.attr,
519 &sensor_dev_attr_in6_min.dev_attr.attr,
520 &sensor_dev_attr_in6_max.dev_attr.attr,
521 &sensor_dev_attr_in6_lcrit.dev_attr.attr,
522 &sensor_dev_attr_in6_crit.dev_attr.attr,
523 &sensor_dev_attr_in6_crit_alarm.dev_attr.attr,
525 &sensor_dev_attr_in7_input.dev_attr.attr,
526 &sensor_dev_attr_in7_min.dev_attr.attr,
527 &sensor_dev_attr_in7_max.dev_attr.attr,
528 &sensor_dev_attr_in7_lcrit.dev_attr.attr,
529 &sensor_dev_attr_in7_crit.dev_attr.attr,
530 &sensor_dev_attr_in7_crit_alarm.dev_attr.attr,
532 &sensor_dev_attr_in8_input.dev_attr.attr,
533 &sensor_dev_attr_in8_min.dev_attr.attr,
534 &sensor_dev_attr_in8_max.dev_attr.attr,
535 &sensor_dev_attr_in8_lcrit.dev_attr.attr,
536 &sensor_dev_attr_in8_crit.dev_attr.attr,
537 &sensor_dev_attr_in8_crit_alarm.dev_attr.attr,
539 &sensor_dev_attr_in9_input.dev_attr.attr,
540 &sensor_dev_attr_in9_min.dev_attr.attr,
541 &sensor_dev_attr_in9_max.dev_attr.attr,
542 &sensor_dev_attr_in9_lcrit.dev_attr.attr,
543 &sensor_dev_attr_in9_crit.dev_attr.attr,
544 &sensor_dev_attr_in9_crit_alarm.dev_attr.attr,
546 &sensor_dev_attr_in10_input.dev_attr.attr,
547 &sensor_dev_attr_in10_min.dev_attr.attr,
548 &sensor_dev_attr_in10_max.dev_attr.attr,
549 &sensor_dev_attr_in10_lcrit.dev_attr.attr,
550 &sensor_dev_attr_in10_crit.dev_attr.attr,
551 &sensor_dev_attr_in10_crit_alarm.dev_attr.attr,
553 &sensor_dev_attr_temp1_input.dev_attr.attr,
554 &sensor_dev_attr_temp1_min.dev_attr.attr,
555 &sensor_dev_attr_temp1_max.dev_attr.attr,
556 &sensor_dev_attr_temp1_lcrit.dev_attr.attr,
557 &sensor_dev_attr_temp1_crit.dev_attr.attr,
558 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
563 ATTRIBUTE_GROUPS(smm665);
565 static const struct i2c_device_id smm665_id[];
567 static int smm665_probe(struct i2c_client *client)
569 struct i2c_adapter *adapter = client->adapter;
570 struct smm665_data *data;
571 struct device *hwmon_dev;
574 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
575 | I2C_FUNC_SMBUS_WORD_DATA))
578 if (i2c_smbus_read_byte_data(client, SMM665_ADOC_ENABLE) < 0)
581 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
585 i2c_set_clientdata(client, data);
586 mutex_init(&data->update_lock);
588 data->client = client;
589 data->type = i2c_match_id(smm665_id, client)->driver_data;
590 data->cmdreg = i2c_new_dummy_device(adapter, (client->addr & ~SMM665_REGMASK)
591 | SMM665_CMDREG_BASE);
592 if (IS_ERR(data->cmdreg))
593 return PTR_ERR(data->cmdreg);
595 switch (data->type) {
598 data->conversion_time = SMM665_ADC_WAIT_SMM665;
603 data->conversion_time = SMM665_ADC_WAIT_SMM766;
608 if (i2c_smbus_read_byte_data(data->cmdreg, SMM665_MISC8_CMD_STS) < 0)
614 * Limit registers start with register SMM665_LIMIT_BASE.
615 * Each channel uses 8 registers, providing four limit values
616 * per channel. Each limit value requires two registers, with the
617 * high byte in the first register and the low byte in the second
618 * register. The first two limits are under limit values, followed
619 * by two over limit values.
621 * Limit register order matches the ADC register order, so we use
622 * ADC register defines throughout the code to index limit registers.
624 * We save the first retrieved value both as "critical" and "alarm"
625 * value. The second value overwrites either the critical or the
626 * alarm value, depending on its configuration. This ensures that both
627 * critical and alarm values are initialized, even if both registers are
628 * configured as critical or non-critical.
630 for (i = 0; i < SMM665_NUM_ADC; i++) {
633 val = smm665_read16(client, SMM665_LIMIT_BASE + i * 8);
634 if (unlikely(val < 0))
636 data->critical_min_limit[i] = data->alarm_min_limit[i]
637 = smm665_convert(val, i);
638 val = smm665_read16(client, SMM665_LIMIT_BASE + i * 8 + 2);
639 if (unlikely(val < 0))
641 if (smm665_is_critical(val))
642 data->critical_min_limit[i] = smm665_convert(val, i);
644 data->alarm_min_limit[i] = smm665_convert(val, i);
645 val = smm665_read16(client, SMM665_LIMIT_BASE + i * 8 + 4);
646 if (unlikely(val < 0))
648 data->critical_max_limit[i] = data->alarm_max_limit[i]
649 = smm665_convert(val, i);
650 val = smm665_read16(client, SMM665_LIMIT_BASE + i * 8 + 6);
651 if (unlikely(val < 0))
653 if (smm665_is_critical(val))
654 data->critical_max_limit[i] = smm665_convert(val, i);
656 data->alarm_max_limit[i] = smm665_convert(val, i);
659 hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
662 if (IS_ERR(hwmon_dev)) {
663 ret = PTR_ERR(hwmon_dev);
670 i2c_unregister_device(data->cmdreg);
674 static void smm665_remove(struct i2c_client *client)
676 struct smm665_data *data = i2c_get_clientdata(client);
678 i2c_unregister_device(data->cmdreg);
681 static const struct i2c_device_id smm665_id[] = {
684 {"smm665c", smm665c},
690 MODULE_DEVICE_TABLE(i2c, smm665_id);
692 /* This is the driver that will be inserted */
693 static struct i2c_driver smm665_driver = {
697 .probe = smm665_probe,
698 .remove = smm665_remove,
699 .id_table = smm665_id,
702 module_i2c_driver(smm665_driver);
704 MODULE_AUTHOR("Guenter Roeck");
705 MODULE_DESCRIPTION("SMM665 driver");
706 MODULE_LICENSE("GPL");