xref: /openbmc/linux/drivers/hwmon/max16065.c (revision 6fa24b41)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for
4  *  Maxim MAX16065/MAX16066 12-Channel/8-Channel, Flash-Configurable
5  *  System Managers with Nonvolatile Fault Registers
6  *  Maxim MAX16067/MAX16068 6-Channel, Flash-Configurable System Managers
7  *  with Nonvolatile Fault Registers
8  *  Maxim MAX16070/MAX16071 12-Channel/8-Channel, Flash-Configurable System
9  *  Monitors with Nonvolatile Fault Registers
10  *
11  * Copyright (C) 2011 Ericsson AB.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/err.h>
18 #include <linux/slab.h>
19 #include <linux/i2c.h>
20 #include <linux/hwmon.h>
21 #include <linux/hwmon-sysfs.h>
22 #include <linux/jiffies.h>
23 
24 enum chips { max16065, max16066, max16067, max16068, max16070, max16071 };
25 
26 /*
27  * Registers
28  */
29 #define MAX16065_ADC(x)		((x) * 2)
30 
31 #define MAX16065_CURR_SENSE	0x18
32 #define MAX16065_CSP_ADC	0x19
33 #define MAX16065_FAULT(x)	(0x1b + (x))
34 #define MAX16065_SCALE(x)	(0x43 + (x))
35 #define MAX16065_CURR_CONTROL	0x47
36 #define MAX16065_LIMIT(l, x)	(0x48 + (l) + (x) * 3)	/*
37 							 * l: limit
38 							 *  0: min/max
39 							 *  1: crit
40 							 *  2: lcrit
41 							 * x: ADC index
42 							 */
43 
44 #define MAX16065_SW_ENABLE	0x73
45 
46 #define MAX16065_WARNING_OV	(1 << 3) /* Set if secondary threshold is OV
47 					    warning */
48 
49 #define MAX16065_CURR_ENABLE	(1 << 0)
50 
51 #define MAX16065_NUM_LIMIT	3
52 #define MAX16065_NUM_ADC	12	/* maximum number of ADC channels */
53 
54 static const int max16065_num_adc[] = {
55 	[max16065] = 12,
56 	[max16066] = 8,
57 	[max16067] = 6,
58 	[max16068] = 6,
59 	[max16070] = 12,
60 	[max16071] = 8,
61 };
62 
63 static const bool max16065_have_secondary[] = {
64 	[max16065] = true,
65 	[max16066] = true,
66 	[max16067] = false,
67 	[max16068] = false,
68 	[max16070] = true,
69 	[max16071] = true,
70 };
71 
72 static const bool max16065_have_current[] = {
73 	[max16065] = true,
74 	[max16066] = true,
75 	[max16067] = false,
76 	[max16068] = false,
77 	[max16070] = true,
78 	[max16071] = true,
79 };
80 
81 struct max16065_data {
82 	enum chips chip;
83 	struct i2c_client *client;
84 	const struct attribute_group *groups[4];
85 	struct mutex update_lock;
86 	bool valid;
87 	unsigned long last_updated; /* in jiffies */
88 	int num_adc;
89 	bool have_current;
90 	int curr_gain;
91 	/* limits are in mV */
92 	int limit[MAX16065_NUM_LIMIT][MAX16065_NUM_ADC];
93 	int range[MAX16065_NUM_ADC + 1];/* voltage range */
94 	int adc[MAX16065_NUM_ADC + 1];	/* adc values (raw) including csp_adc */
95 	int curr_sense;
96 	int fault[2];
97 };
98 
99 static const int max16065_adc_range[] = { 5560, 2780, 1390, 0 };
100 static const int max16065_csp_adc_range[] = { 7000, 14000 };
101 
102 /* ADC registers have 10 bit resolution. */
103 static inline int ADC_TO_MV(int adc, int range)
104 {
105 	return (adc * range) / 1024;
106 }
107 
108 /*
109  * Limit registers have 8 bit resolution and match upper 8 bits of ADC
110  * registers.
111  */
112 static inline int LIMIT_TO_MV(int limit, int range)
113 {
114 	return limit * range / 256;
115 }
116 
117 static inline int MV_TO_LIMIT(unsigned long mv, int range)
118 {
119 	mv = clamp_val(mv, 0, ULONG_MAX / 256);
120 	return DIV_ROUND_CLOSEST(clamp_val(mv * 256, 0, range * 255), range);
121 }
122 
123 static inline int ADC_TO_CURR(int adc, int gain)
124 {
125 	return adc * 1400000 / (gain * 255);
126 }
127 
128 /*
129  * max16065_read_adc()
130  *
131  * Read 16 bit value from <reg>, <reg+1>.
132  * Upper 8 bits are in <reg>, lower 2 bits are in bits 7:6 of <reg+1>.
133  */
134 static int max16065_read_adc(struct i2c_client *client, int reg)
135 {
136 	int rv;
137 
138 	rv = i2c_smbus_read_word_swapped(client, reg);
139 	if (unlikely(rv < 0))
140 		return rv;
141 	return rv >> 6;
142 }
143 
144 static struct max16065_data *max16065_update_device(struct device *dev)
145 {
146 	struct max16065_data *data = dev_get_drvdata(dev);
147 	struct i2c_client *client = data->client;
148 
149 	mutex_lock(&data->update_lock);
150 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
151 		int i;
152 
153 		for (i = 0; i < data->num_adc; i++)
154 			data->adc[i]
155 			  = max16065_read_adc(client, MAX16065_ADC(i));
156 
157 		if (data->have_current) {
158 			data->adc[MAX16065_NUM_ADC]
159 			  = max16065_read_adc(client, MAX16065_CSP_ADC);
160 			data->curr_sense
161 			  = i2c_smbus_read_byte_data(client,
162 						     MAX16065_CURR_SENSE);
163 		}
164 
165 		for (i = 0; i < 2; i++)
166 			data->fault[i]
167 			  = i2c_smbus_read_byte_data(client, MAX16065_FAULT(i));
168 
169 		/*
170 		 * MAX16067 and MAX16068 have separate undervoltage and
171 		 * overvoltage alarm bits. Squash them together.
172 		 */
173 		if (data->chip == max16067 || data->chip == max16068)
174 			data->fault[0] |= data->fault[1];
175 
176 		data->last_updated = jiffies;
177 		data->valid = true;
178 	}
179 	mutex_unlock(&data->update_lock);
180 	return data;
181 }
182 
183 static ssize_t max16065_alarm_show(struct device *dev,
184 				   struct device_attribute *da, char *buf)
185 {
186 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(da);
187 	struct max16065_data *data = max16065_update_device(dev);
188 	int val = data->fault[attr2->nr];
189 
190 	if (val < 0)
191 		return val;
192 
193 	val &= (1 << attr2->index);
194 	if (val)
195 		i2c_smbus_write_byte_data(data->client,
196 					  MAX16065_FAULT(attr2->nr), val);
197 
198 	return sysfs_emit(buf, "%d\n", !!val);
199 }
200 
201 static ssize_t max16065_input_show(struct device *dev,
202 				   struct device_attribute *da, char *buf)
203 {
204 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
205 	struct max16065_data *data = max16065_update_device(dev);
206 	int adc = data->adc[attr->index];
207 
208 	if (unlikely(adc < 0))
209 		return adc;
210 
211 	return sysfs_emit(buf, "%d\n",
212 			  ADC_TO_MV(adc, data->range[attr->index]));
213 }
214 
215 static ssize_t max16065_current_show(struct device *dev,
216 				     struct device_attribute *da, char *buf)
217 {
218 	struct max16065_data *data = max16065_update_device(dev);
219 
220 	if (unlikely(data->curr_sense < 0))
221 		return data->curr_sense;
222 
223 	return sysfs_emit(buf, "%d\n",
224 			  ADC_TO_CURR(data->curr_sense, data->curr_gain));
225 }
226 
227 static ssize_t max16065_limit_store(struct device *dev,
228 				    struct device_attribute *da,
229 				    const char *buf, size_t count)
230 {
231 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(da);
232 	struct max16065_data *data = dev_get_drvdata(dev);
233 	unsigned long val;
234 	int err;
235 	int limit;
236 
237 	err = kstrtoul(buf, 10, &val);
238 	if (unlikely(err < 0))
239 		return err;
240 
241 	limit = MV_TO_LIMIT(val, data->range[attr2->index]);
242 
243 	mutex_lock(&data->update_lock);
244 	data->limit[attr2->nr][attr2->index]
245 	  = LIMIT_TO_MV(limit, data->range[attr2->index]);
246 	i2c_smbus_write_byte_data(data->client,
247 				  MAX16065_LIMIT(attr2->nr, attr2->index),
248 				  limit);
249 	mutex_unlock(&data->update_lock);
250 
251 	return count;
252 }
253 
254 static ssize_t max16065_limit_show(struct device *dev,
255 				   struct device_attribute *da, char *buf)
256 {
257 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(da);
258 	struct max16065_data *data = dev_get_drvdata(dev);
259 
260 	return sysfs_emit(buf, "%d\n",
261 			  data->limit[attr2->nr][attr2->index]);
262 }
263 
264 /* Construct a sensor_device_attribute structure for each register */
265 
266 /* Input voltages */
267 static SENSOR_DEVICE_ATTR_RO(in0_input, max16065_input, 0);
268 static SENSOR_DEVICE_ATTR_RO(in1_input, max16065_input, 1);
269 static SENSOR_DEVICE_ATTR_RO(in2_input, max16065_input, 2);
270 static SENSOR_DEVICE_ATTR_RO(in3_input, max16065_input, 3);
271 static SENSOR_DEVICE_ATTR_RO(in4_input, max16065_input, 4);
272 static SENSOR_DEVICE_ATTR_RO(in5_input, max16065_input, 5);
273 static SENSOR_DEVICE_ATTR_RO(in6_input, max16065_input, 6);
274 static SENSOR_DEVICE_ATTR_RO(in7_input, max16065_input, 7);
275 static SENSOR_DEVICE_ATTR_RO(in8_input, max16065_input, 8);
276 static SENSOR_DEVICE_ATTR_RO(in9_input, max16065_input, 9);
277 static SENSOR_DEVICE_ATTR_RO(in10_input, max16065_input, 10);
278 static SENSOR_DEVICE_ATTR_RO(in11_input, max16065_input, 11);
279 static SENSOR_DEVICE_ATTR_RO(in12_input, max16065_input, 12);
280 
281 /* Input voltages lcrit */
282 static SENSOR_DEVICE_ATTR_2_RW(in0_lcrit, max16065_limit, 2, 0);
283 static SENSOR_DEVICE_ATTR_2_RW(in1_lcrit, max16065_limit, 2, 1);
284 static SENSOR_DEVICE_ATTR_2_RW(in2_lcrit, max16065_limit, 2, 2);
285 static SENSOR_DEVICE_ATTR_2_RW(in3_lcrit, max16065_limit, 2, 3);
286 static SENSOR_DEVICE_ATTR_2_RW(in4_lcrit, max16065_limit, 2, 4);
287 static SENSOR_DEVICE_ATTR_2_RW(in5_lcrit, max16065_limit, 2, 5);
288 static SENSOR_DEVICE_ATTR_2_RW(in6_lcrit, max16065_limit, 2, 6);
289 static SENSOR_DEVICE_ATTR_2_RW(in7_lcrit, max16065_limit, 2, 7);
290 static SENSOR_DEVICE_ATTR_2_RW(in8_lcrit, max16065_limit, 2, 8);
291 static SENSOR_DEVICE_ATTR_2_RW(in9_lcrit, max16065_limit, 2, 9);
292 static SENSOR_DEVICE_ATTR_2_RW(in10_lcrit, max16065_limit, 2, 10);
293 static SENSOR_DEVICE_ATTR_2_RW(in11_lcrit, max16065_limit, 2, 11);
294 
295 /* Input voltages crit */
296 static SENSOR_DEVICE_ATTR_2_RW(in0_crit, max16065_limit, 1, 0);
297 static SENSOR_DEVICE_ATTR_2_RW(in1_crit, max16065_limit, 1, 1);
298 static SENSOR_DEVICE_ATTR_2_RW(in2_crit, max16065_limit, 1, 2);
299 static SENSOR_DEVICE_ATTR_2_RW(in3_crit, max16065_limit, 1, 3);
300 static SENSOR_DEVICE_ATTR_2_RW(in4_crit, max16065_limit, 1, 4);
301 static SENSOR_DEVICE_ATTR_2_RW(in5_crit, max16065_limit, 1, 5);
302 static SENSOR_DEVICE_ATTR_2_RW(in6_crit, max16065_limit, 1, 6);
303 static SENSOR_DEVICE_ATTR_2_RW(in7_crit, max16065_limit, 1, 7);
304 static SENSOR_DEVICE_ATTR_2_RW(in8_crit, max16065_limit, 1, 8);
305 static SENSOR_DEVICE_ATTR_2_RW(in9_crit, max16065_limit, 1, 9);
306 static SENSOR_DEVICE_ATTR_2_RW(in10_crit, max16065_limit, 1, 10);
307 static SENSOR_DEVICE_ATTR_2_RW(in11_crit, max16065_limit, 1, 11);
308 
309 /* Input voltages min */
310 static SENSOR_DEVICE_ATTR_2_RW(in0_min, max16065_limit, 0, 0);
311 static SENSOR_DEVICE_ATTR_2_RW(in1_min, max16065_limit, 0, 1);
312 static SENSOR_DEVICE_ATTR_2_RW(in2_min, max16065_limit, 0, 2);
313 static SENSOR_DEVICE_ATTR_2_RW(in3_min, max16065_limit, 0, 3);
314 static SENSOR_DEVICE_ATTR_2_RW(in4_min, max16065_limit, 0, 4);
315 static SENSOR_DEVICE_ATTR_2_RW(in5_min, max16065_limit, 0, 5);
316 static SENSOR_DEVICE_ATTR_2_RW(in6_min, max16065_limit, 0, 6);
317 static SENSOR_DEVICE_ATTR_2_RW(in7_min, max16065_limit, 0, 7);
318 static SENSOR_DEVICE_ATTR_2_RW(in8_min, max16065_limit, 0, 8);
319 static SENSOR_DEVICE_ATTR_2_RW(in9_min, max16065_limit, 0, 9);
320 static SENSOR_DEVICE_ATTR_2_RW(in10_min, max16065_limit, 0, 10);
321 static SENSOR_DEVICE_ATTR_2_RW(in11_min, max16065_limit, 0, 11);
322 
323 /* Input voltages max */
324 static SENSOR_DEVICE_ATTR_2_RW(in0_max, max16065_limit, 0, 0);
325 static SENSOR_DEVICE_ATTR_2_RW(in1_max, max16065_limit, 0, 1);
326 static SENSOR_DEVICE_ATTR_2_RW(in2_max, max16065_limit, 0, 2);
327 static SENSOR_DEVICE_ATTR_2_RW(in3_max, max16065_limit, 0, 3);
328 static SENSOR_DEVICE_ATTR_2_RW(in4_max, max16065_limit, 0, 4);
329 static SENSOR_DEVICE_ATTR_2_RW(in5_max, max16065_limit, 0, 5);
330 static SENSOR_DEVICE_ATTR_2_RW(in6_max, max16065_limit, 0, 6);
331 static SENSOR_DEVICE_ATTR_2_RW(in7_max, max16065_limit, 0, 7);
332 static SENSOR_DEVICE_ATTR_2_RW(in8_max, max16065_limit, 0, 8);
333 static SENSOR_DEVICE_ATTR_2_RW(in9_max, max16065_limit, 0, 9);
334 static SENSOR_DEVICE_ATTR_2_RW(in10_max, max16065_limit, 0, 10);
335 static SENSOR_DEVICE_ATTR_2_RW(in11_max, max16065_limit, 0, 11);
336 
337 /* alarms */
338 static SENSOR_DEVICE_ATTR_2_RO(in0_alarm, max16065_alarm, 0, 0);
339 static SENSOR_DEVICE_ATTR_2_RO(in1_alarm, max16065_alarm, 0, 1);
340 static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, max16065_alarm, 0, 2);
341 static SENSOR_DEVICE_ATTR_2_RO(in3_alarm, max16065_alarm, 0, 3);
342 static SENSOR_DEVICE_ATTR_2_RO(in4_alarm, max16065_alarm, 0, 4);
343 static SENSOR_DEVICE_ATTR_2_RO(in5_alarm, max16065_alarm, 0, 5);
344 static SENSOR_DEVICE_ATTR_2_RO(in6_alarm, max16065_alarm, 0, 6);
345 static SENSOR_DEVICE_ATTR_2_RO(in7_alarm, max16065_alarm, 0, 7);
346 static SENSOR_DEVICE_ATTR_2_RO(in8_alarm, max16065_alarm, 1, 0);
347 static SENSOR_DEVICE_ATTR_2_RO(in9_alarm, max16065_alarm, 1, 1);
348 static SENSOR_DEVICE_ATTR_2_RO(in10_alarm, max16065_alarm, 1, 2);
349 static SENSOR_DEVICE_ATTR_2_RO(in11_alarm, max16065_alarm, 1, 3);
350 
351 /* Current and alarm */
352 static SENSOR_DEVICE_ATTR_RO(curr1_input, max16065_current, 0);
353 static SENSOR_DEVICE_ATTR_2_RO(curr1_alarm, max16065_alarm, 1, 4);
354 
355 /*
356  * Finally, construct an array of pointers to members of the above objects,
357  * as required for sysfs_create_group()
358  */
359 static struct attribute *max16065_basic_attributes[] = {
360 	&sensor_dev_attr_in0_input.dev_attr.attr,
361 	&sensor_dev_attr_in0_lcrit.dev_attr.attr,
362 	&sensor_dev_attr_in0_crit.dev_attr.attr,
363 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
364 
365 	&sensor_dev_attr_in1_input.dev_attr.attr,
366 	&sensor_dev_attr_in1_lcrit.dev_attr.attr,
367 	&sensor_dev_attr_in1_crit.dev_attr.attr,
368 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
369 
370 	&sensor_dev_attr_in2_input.dev_attr.attr,
371 	&sensor_dev_attr_in2_lcrit.dev_attr.attr,
372 	&sensor_dev_attr_in2_crit.dev_attr.attr,
373 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
374 
375 	&sensor_dev_attr_in3_input.dev_attr.attr,
376 	&sensor_dev_attr_in3_lcrit.dev_attr.attr,
377 	&sensor_dev_attr_in3_crit.dev_attr.attr,
378 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
379 
380 	&sensor_dev_attr_in4_input.dev_attr.attr,
381 	&sensor_dev_attr_in4_lcrit.dev_attr.attr,
382 	&sensor_dev_attr_in4_crit.dev_attr.attr,
383 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
384 
385 	&sensor_dev_attr_in5_input.dev_attr.attr,
386 	&sensor_dev_attr_in5_lcrit.dev_attr.attr,
387 	&sensor_dev_attr_in5_crit.dev_attr.attr,
388 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
389 
390 	&sensor_dev_attr_in6_input.dev_attr.attr,
391 	&sensor_dev_attr_in6_lcrit.dev_attr.attr,
392 	&sensor_dev_attr_in6_crit.dev_attr.attr,
393 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
394 
395 	&sensor_dev_attr_in7_input.dev_attr.attr,
396 	&sensor_dev_attr_in7_lcrit.dev_attr.attr,
397 	&sensor_dev_attr_in7_crit.dev_attr.attr,
398 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
399 
400 	&sensor_dev_attr_in8_input.dev_attr.attr,
401 	&sensor_dev_attr_in8_lcrit.dev_attr.attr,
402 	&sensor_dev_attr_in8_crit.dev_attr.attr,
403 	&sensor_dev_attr_in8_alarm.dev_attr.attr,
404 
405 	&sensor_dev_attr_in9_input.dev_attr.attr,
406 	&sensor_dev_attr_in9_lcrit.dev_attr.attr,
407 	&sensor_dev_attr_in9_crit.dev_attr.attr,
408 	&sensor_dev_attr_in9_alarm.dev_attr.attr,
409 
410 	&sensor_dev_attr_in10_input.dev_attr.attr,
411 	&sensor_dev_attr_in10_lcrit.dev_attr.attr,
412 	&sensor_dev_attr_in10_crit.dev_attr.attr,
413 	&sensor_dev_attr_in10_alarm.dev_attr.attr,
414 
415 	&sensor_dev_attr_in11_input.dev_attr.attr,
416 	&sensor_dev_attr_in11_lcrit.dev_attr.attr,
417 	&sensor_dev_attr_in11_crit.dev_attr.attr,
418 	&sensor_dev_attr_in11_alarm.dev_attr.attr,
419 
420 	NULL
421 };
422 
423 static struct attribute *max16065_current_attributes[] = {
424 	&sensor_dev_attr_in12_input.dev_attr.attr,
425 	&sensor_dev_attr_curr1_input.dev_attr.attr,
426 	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
427 	NULL
428 };
429 
430 static struct attribute *max16065_min_attributes[] = {
431 	&sensor_dev_attr_in0_min.dev_attr.attr,
432 	&sensor_dev_attr_in1_min.dev_attr.attr,
433 	&sensor_dev_attr_in2_min.dev_attr.attr,
434 	&sensor_dev_attr_in3_min.dev_attr.attr,
435 	&sensor_dev_attr_in4_min.dev_attr.attr,
436 	&sensor_dev_attr_in5_min.dev_attr.attr,
437 	&sensor_dev_attr_in6_min.dev_attr.attr,
438 	&sensor_dev_attr_in7_min.dev_attr.attr,
439 	&sensor_dev_attr_in8_min.dev_attr.attr,
440 	&sensor_dev_attr_in9_min.dev_attr.attr,
441 	&sensor_dev_attr_in10_min.dev_attr.attr,
442 	&sensor_dev_attr_in11_min.dev_attr.attr,
443 	NULL
444 };
445 
446 static struct attribute *max16065_max_attributes[] = {
447 	&sensor_dev_attr_in0_max.dev_attr.attr,
448 	&sensor_dev_attr_in1_max.dev_attr.attr,
449 	&sensor_dev_attr_in2_max.dev_attr.attr,
450 	&sensor_dev_attr_in3_max.dev_attr.attr,
451 	&sensor_dev_attr_in4_max.dev_attr.attr,
452 	&sensor_dev_attr_in5_max.dev_attr.attr,
453 	&sensor_dev_attr_in6_max.dev_attr.attr,
454 	&sensor_dev_attr_in7_max.dev_attr.attr,
455 	&sensor_dev_attr_in8_max.dev_attr.attr,
456 	&sensor_dev_attr_in9_max.dev_attr.attr,
457 	&sensor_dev_attr_in10_max.dev_attr.attr,
458 	&sensor_dev_attr_in11_max.dev_attr.attr,
459 	NULL
460 };
461 
462 static umode_t max16065_basic_is_visible(struct kobject *kobj,
463 					 struct attribute *a, int n)
464 {
465 	struct device *dev = kobj_to_dev(kobj);
466 	struct max16065_data *data = dev_get_drvdata(dev);
467 	int index = n / 4;
468 
469 	if (index >= data->num_adc || !data->range[index])
470 		return 0;
471 	return a->mode;
472 }
473 
474 static umode_t max16065_secondary_is_visible(struct kobject *kobj,
475 					     struct attribute *a, int index)
476 {
477 	struct device *dev = kobj_to_dev(kobj);
478 	struct max16065_data *data = dev_get_drvdata(dev);
479 
480 	if (index >= data->num_adc)
481 		return 0;
482 	return a->mode;
483 }
484 
485 static const struct attribute_group max16065_basic_group = {
486 	.attrs = max16065_basic_attributes,
487 	.is_visible = max16065_basic_is_visible,
488 };
489 
490 static const struct attribute_group max16065_current_group = {
491 	.attrs = max16065_current_attributes,
492 };
493 
494 static const struct attribute_group max16065_min_group = {
495 	.attrs = max16065_min_attributes,
496 	.is_visible = max16065_secondary_is_visible,
497 };
498 
499 static const struct attribute_group max16065_max_group = {
500 	.attrs = max16065_max_attributes,
501 	.is_visible = max16065_secondary_is_visible,
502 };
503 
504 static int max16065_probe(struct i2c_client *client)
505 {
506 	struct i2c_adapter *adapter = client->adapter;
507 	struct max16065_data *data;
508 	struct device *dev = &client->dev;
509 	struct device *hwmon_dev;
510 	int i, j, val;
511 	bool have_secondary;		/* true if chip has secondary limits */
512 	bool secondary_is_max = false;	/* secondary limits reflect max */
513 	int groups = 0;
514 	enum chips chip = (uintptr_t)i2c_get_match_data(client);
515 
516 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
517 				     | I2C_FUNC_SMBUS_READ_WORD_DATA))
518 		return -ENODEV;
519 
520 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
521 	if (unlikely(!data))
522 		return -ENOMEM;
523 
524 	data->chip = chip;
525 	data->client = client;
526 	mutex_init(&data->update_lock);
527 
528 	data->num_adc = max16065_num_adc[chip];
529 	data->have_current = max16065_have_current[chip];
530 	have_secondary = max16065_have_secondary[chip];
531 
532 	if (have_secondary) {
533 		val = i2c_smbus_read_byte_data(client, MAX16065_SW_ENABLE);
534 		if (unlikely(val < 0))
535 			return val;
536 		secondary_is_max = val & MAX16065_WARNING_OV;
537 	}
538 
539 	/* Read scale registers, convert to range */
540 	for (i = 0; i < DIV_ROUND_UP(data->num_adc, 4); i++) {
541 		val = i2c_smbus_read_byte_data(client, MAX16065_SCALE(i));
542 		if (unlikely(val < 0))
543 			return val;
544 		for (j = 0; j < 4 && i * 4 + j < data->num_adc; j++) {
545 			data->range[i * 4 + j] =
546 			  max16065_adc_range[(val >> (j * 2)) & 0x3];
547 		}
548 	}
549 
550 	/* Read limits */
551 	for (i = 0; i < MAX16065_NUM_LIMIT; i++) {
552 		if (i == 0 && !have_secondary)
553 			continue;
554 
555 		for (j = 0; j < data->num_adc; j++) {
556 			val = i2c_smbus_read_byte_data(client,
557 						       MAX16065_LIMIT(i, j));
558 			if (unlikely(val < 0))
559 				return val;
560 			data->limit[i][j] = LIMIT_TO_MV(val, data->range[j]);
561 		}
562 	}
563 
564 	/* sysfs hooks */
565 	data->groups[groups++] = &max16065_basic_group;
566 	if (have_secondary)
567 		data->groups[groups++] = secondary_is_max ?
568 			&max16065_max_group : &max16065_min_group;
569 
570 	if (data->have_current) {
571 		val = i2c_smbus_read_byte_data(client, MAX16065_CURR_CONTROL);
572 		if (unlikely(val < 0))
573 			return val;
574 		if (val & MAX16065_CURR_ENABLE) {
575 			/*
576 			 * Current gain is 6, 12, 24, 48 based on values in
577 			 * bit 2,3.
578 			 */
579 			data->curr_gain = 6 << ((val >> 2) & 0x03);
580 			data->range[MAX16065_NUM_ADC]
581 			  = max16065_csp_adc_range[(val >> 1) & 0x01];
582 			data->groups[groups++] = &max16065_current_group;
583 		} else {
584 			data->have_current = false;
585 		}
586 	}
587 
588 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
589 							   data, data->groups);
590 	return PTR_ERR_OR_ZERO(hwmon_dev);
591 }
592 
593 static const struct i2c_device_id max16065_id[] = {
594 	{ "max16065", max16065 },
595 	{ "max16066", max16066 },
596 	{ "max16067", max16067 },
597 	{ "max16068", max16068 },
598 	{ "max16070", max16070 },
599 	{ "max16071", max16071 },
600 	{ }
601 };
602 
603 MODULE_DEVICE_TABLE(i2c, max16065_id);
604 
605 /* This is the driver that will be inserted */
606 static struct i2c_driver max16065_driver = {
607 	.driver = {
608 		.name = "max16065",
609 	},
610 	.probe = max16065_probe,
611 	.id_table = max16065_id,
612 };
613 
614 module_i2c_driver(max16065_driver);
615 
616 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
617 MODULE_DESCRIPTION("MAX16065 driver");
618 MODULE_LICENSE("GPL");
619