xref: /linux/drivers/hwmon/max6697.c (revision d538d94f0ca86cfedc892cc427169219acb3c2f7)
1 /*
2  * Copyright (c) 2012 Guenter Roeck <linux@roeck-us.net>
3  *
4  * based on max1668.c
5  * Copyright (c) 2011 David George <david.george@ska.ac.za>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/jiffies.h>
22 #include <linux/i2c.h>
23 #include <linux/hwmon.h>
24 #include <linux/hwmon-sysfs.h>
25 #include <linux/err.h>
26 #include <linux/mutex.h>
27 #include <linux/of_device.h>
28 #include <linux/of.h>
29 
30 #include <linux/platform_data/max6697.h>
31 
32 enum chips { max6581, max6602, max6622, max6636, max6689, max6693, max6694,
33 	     max6697, max6698, max6699 };
34 
35 /* Report local sensor as temp1 */
36 
37 static const u8 MAX6697_REG_TEMP[] = {
38 			0x07, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x08 };
39 static const u8 MAX6697_REG_TEMP_EXT[] = {
40 			0x57, 0x09, 0x52, 0x53, 0x54, 0x55, 0x56, 0 };
41 static const u8 MAX6697_REG_MAX[] = {
42 			0x17, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x18 };
43 static const u8 MAX6697_REG_CRIT[] = {
44 			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27 };
45 
46 /*
47  * Map device tree / platform data register bit map to chip bit map.
48  * Applies to alert register and over-temperature register.
49  */
50 #define MAX6697_MAP_BITS(reg)	((((reg) & 0x7e) >> 1) | \
51 				 (((reg) & 0x01) << 6) | ((reg) & 0x80))
52 
53 #define MAX6697_REG_STAT(n)		(0x44 + (n))
54 
55 #define MAX6697_REG_CONFIG		0x41
56 #define MAX6581_CONF_EXTENDED		(1 << 1)
57 #define MAX6693_CONF_BETA		(1 << 2)
58 #define MAX6697_CONF_RESISTANCE		(1 << 3)
59 #define MAX6697_CONF_TIMEOUT		(1 << 5)
60 #define MAX6697_REG_ALERT_MASK		0x42
61 #define MAX6697_REG_OVERT_MASK		0x43
62 
63 #define MAX6581_REG_RESISTANCE		0x4a
64 #define MAX6581_REG_IDEALITY		0x4b
65 #define MAX6581_REG_IDEALITY_SELECT	0x4c
66 #define MAX6581_REG_OFFSET		0x4d
67 #define MAX6581_REG_OFFSET_SELECT	0x4e
68 
69 #define MAX6697_CONV_TIME		156	/* ms per channel, worst case */
70 
71 struct max6697_chip_data {
72 	int channels;
73 	u32 have_ext;
74 	u32 have_crit;
75 	u32 have_fault;
76 	u8 valid_conf;
77 	const u8 *alarm_map;
78 };
79 
80 struct max6697_data {
81 	struct i2c_client *client;
82 
83 	enum chips type;
84 	const struct max6697_chip_data *chip;
85 
86 	int update_interval;	/* in milli-seconds */
87 	int temp_offset;	/* in degrees C */
88 
89 	struct mutex update_lock;
90 	unsigned long last_updated;	/* In jiffies */
91 	bool valid;		/* true if following fields are valid */
92 
93 	/* 1x local and up to 7x remote */
94 	u8 temp[8][4];		/* [nr][0]=temp [1]=ext [2]=max [3]=crit */
95 #define MAX6697_TEMP_INPUT	0
96 #define MAX6697_TEMP_EXT	1
97 #define MAX6697_TEMP_MAX	2
98 #define MAX6697_TEMP_CRIT	3
99 	u32 alarms;
100 };
101 
102 /* Diode fault status bits on MAX6581 are right shifted by one bit */
103 static const u8 max6581_alarm_map[] = {
104 	 0, 0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15,
105 	 16, 17, 18, 19, 20, 21, 22, 23 };
106 
107 static const struct max6697_chip_data max6697_chip_data[] = {
108 	[max6581] = {
109 		.channels = 8,
110 		.have_crit = 0xff,
111 		.have_ext = 0x7f,
112 		.have_fault = 0xfe,
113 		.valid_conf = MAX6581_CONF_EXTENDED | MAX6697_CONF_TIMEOUT,
114 		.alarm_map = max6581_alarm_map,
115 	},
116 	[max6602] = {
117 		.channels = 5,
118 		.have_crit = 0x12,
119 		.have_ext = 0x02,
120 		.have_fault = 0x1e,
121 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
122 	},
123 	[max6622] = {
124 		.channels = 5,
125 		.have_crit = 0x12,
126 		.have_ext = 0x02,
127 		.have_fault = 0x1e,
128 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
129 	},
130 	[max6636] = {
131 		.channels = 7,
132 		.have_crit = 0x72,
133 		.have_ext = 0x02,
134 		.have_fault = 0x7e,
135 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
136 	},
137 	[max6689] = {
138 		.channels = 7,
139 		.have_crit = 0x72,
140 		.have_ext = 0x02,
141 		.have_fault = 0x7e,
142 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
143 	},
144 	[max6693] = {
145 		.channels = 7,
146 		.have_crit = 0x72,
147 		.have_ext = 0x02,
148 		.have_fault = 0x7e,
149 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6693_CONF_BETA |
150 		  MAX6697_CONF_TIMEOUT,
151 	},
152 	[max6694] = {
153 		.channels = 5,
154 		.have_crit = 0x12,
155 		.have_ext = 0x02,
156 		.have_fault = 0x1e,
157 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6693_CONF_BETA |
158 		  MAX6697_CONF_TIMEOUT,
159 	},
160 	[max6697] = {
161 		.channels = 7,
162 		.have_crit = 0x72,
163 		.have_ext = 0x02,
164 		.have_fault = 0x7e,
165 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
166 	},
167 	[max6698] = {
168 		.channels = 7,
169 		.have_crit = 0x72,
170 		.have_ext = 0x02,
171 		.have_fault = 0x0e,
172 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
173 	},
174 	[max6699] = {
175 		.channels = 5,
176 		.have_crit = 0x12,
177 		.have_ext = 0x02,
178 		.have_fault = 0x1e,
179 		.valid_conf = MAX6697_CONF_RESISTANCE | MAX6697_CONF_TIMEOUT,
180 	},
181 };
182 
183 static struct max6697_data *max6697_update_device(struct device *dev)
184 {
185 	struct max6697_data *data = dev_get_drvdata(dev);
186 	struct i2c_client *client = data->client;
187 	struct max6697_data *ret = data;
188 	int val;
189 	int i;
190 	u32 alarms;
191 
192 	mutex_lock(&data->update_lock);
193 
194 	if (data->valid &&
195 	    !time_after(jiffies, data->last_updated
196 			+ msecs_to_jiffies(data->update_interval)))
197 		goto abort;
198 
199 	for (i = 0; i < data->chip->channels; i++) {
200 		if (data->chip->have_ext & (1 << i)) {
201 			val = i2c_smbus_read_byte_data(client,
202 						       MAX6697_REG_TEMP_EXT[i]);
203 			if (unlikely(val < 0)) {
204 				ret = ERR_PTR(val);
205 				goto abort;
206 			}
207 			data->temp[i][MAX6697_TEMP_EXT] = val;
208 		}
209 
210 		val = i2c_smbus_read_byte_data(client, MAX6697_REG_TEMP[i]);
211 		if (unlikely(val < 0)) {
212 			ret = ERR_PTR(val);
213 			goto abort;
214 		}
215 		data->temp[i][MAX6697_TEMP_INPUT] = val;
216 
217 		val = i2c_smbus_read_byte_data(client, MAX6697_REG_MAX[i]);
218 		if (unlikely(val < 0)) {
219 			ret = ERR_PTR(val);
220 			goto abort;
221 		}
222 		data->temp[i][MAX6697_TEMP_MAX] = val;
223 
224 		if (data->chip->have_crit & (1 << i)) {
225 			val = i2c_smbus_read_byte_data(client,
226 						       MAX6697_REG_CRIT[i]);
227 			if (unlikely(val < 0)) {
228 				ret = ERR_PTR(val);
229 				goto abort;
230 			}
231 			data->temp[i][MAX6697_TEMP_CRIT] = val;
232 		}
233 	}
234 
235 	alarms = 0;
236 	for (i = 0; i < 3; i++) {
237 		val = i2c_smbus_read_byte_data(client, MAX6697_REG_STAT(i));
238 		if (unlikely(val < 0)) {
239 			ret = ERR_PTR(val);
240 			goto abort;
241 		}
242 		alarms = (alarms << 8) | val;
243 	}
244 	data->alarms = alarms;
245 	data->last_updated = jiffies;
246 	data->valid = true;
247 abort:
248 	mutex_unlock(&data->update_lock);
249 
250 	return ret;
251 }
252 
253 static ssize_t temp_input_show(struct device *dev,
254 			       struct device_attribute *devattr, char *buf)
255 {
256 	int index = to_sensor_dev_attr(devattr)->index;
257 	struct max6697_data *data = max6697_update_device(dev);
258 	int temp;
259 
260 	if (IS_ERR(data))
261 		return PTR_ERR(data);
262 
263 	temp = (data->temp[index][MAX6697_TEMP_INPUT] - data->temp_offset) << 3;
264 	temp |= data->temp[index][MAX6697_TEMP_EXT] >> 5;
265 
266 	return sprintf(buf, "%d\n", temp * 125);
267 }
268 
269 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
270 			 char *buf)
271 {
272 	int nr = to_sensor_dev_attr_2(devattr)->nr;
273 	int index = to_sensor_dev_attr_2(devattr)->index;
274 	struct max6697_data *data = max6697_update_device(dev);
275 	int temp;
276 
277 	if (IS_ERR(data))
278 		return PTR_ERR(data);
279 
280 	temp = data->temp[nr][index];
281 	temp -= data->temp_offset;
282 
283 	return sprintf(buf, "%d\n", temp * 1000);
284 }
285 
286 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
287 			  char *buf)
288 {
289 	int index = to_sensor_dev_attr(attr)->index;
290 	struct max6697_data *data = max6697_update_device(dev);
291 
292 	if (IS_ERR(data))
293 		return PTR_ERR(data);
294 
295 	if (data->chip->alarm_map)
296 		index = data->chip->alarm_map[index];
297 
298 	return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
299 }
300 
301 static ssize_t temp_store(struct device *dev,
302 			  struct device_attribute *devattr, const char *buf,
303 			  size_t count)
304 {
305 	int nr = to_sensor_dev_attr_2(devattr)->nr;
306 	int index = to_sensor_dev_attr_2(devattr)->index;
307 	struct max6697_data *data = dev_get_drvdata(dev);
308 	long temp;
309 	int ret;
310 
311 	ret = kstrtol(buf, 10, &temp);
312 	if (ret < 0)
313 		return ret;
314 
315 	mutex_lock(&data->update_lock);
316 	temp = DIV_ROUND_CLOSEST(temp, 1000) + data->temp_offset;
317 	temp = clamp_val(temp, 0, data->type == max6581 ? 255 : 127);
318 	data->temp[nr][index] = temp;
319 	ret = i2c_smbus_write_byte_data(data->client,
320 					index == 2 ? MAX6697_REG_MAX[nr]
321 						   : MAX6697_REG_CRIT[nr],
322 					temp);
323 	mutex_unlock(&data->update_lock);
324 
325 	return ret < 0 ? ret : count;
326 }
327 
328 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
329 static SENSOR_DEVICE_ATTR_2_RW(temp1_max, temp, 0, MAX6697_TEMP_MAX);
330 static SENSOR_DEVICE_ATTR_2_RW(temp1_crit, temp, 0, MAX6697_TEMP_CRIT);
331 
332 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
333 static SENSOR_DEVICE_ATTR_2_RW(temp2_max, temp, 1, MAX6697_TEMP_MAX);
334 static SENSOR_DEVICE_ATTR_2_RW(temp2_crit, temp, 1, MAX6697_TEMP_CRIT);
335 
336 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp_input, 2);
337 static SENSOR_DEVICE_ATTR_2_RW(temp3_max, temp, 2, MAX6697_TEMP_MAX);
338 static SENSOR_DEVICE_ATTR_2_RW(temp3_crit, temp, 2, MAX6697_TEMP_CRIT);
339 
340 static SENSOR_DEVICE_ATTR_RO(temp4_input, temp_input, 3);
341 static SENSOR_DEVICE_ATTR_2_RW(temp4_max, temp, 3, MAX6697_TEMP_MAX);
342 static SENSOR_DEVICE_ATTR_2_RW(temp4_crit, temp, 3, MAX6697_TEMP_CRIT);
343 
344 static SENSOR_DEVICE_ATTR_RO(temp5_input, temp_input, 4);
345 static SENSOR_DEVICE_ATTR_2_RW(temp5_max, temp, 4, MAX6697_TEMP_MAX);
346 static SENSOR_DEVICE_ATTR_2_RW(temp5_crit, temp, 4, MAX6697_TEMP_CRIT);
347 
348 static SENSOR_DEVICE_ATTR_RO(temp6_input, temp_input, 5);
349 static SENSOR_DEVICE_ATTR_2_RW(temp6_max, temp, 5, MAX6697_TEMP_MAX);
350 static SENSOR_DEVICE_ATTR_2_RW(temp6_crit, temp, 5, MAX6697_TEMP_CRIT);
351 
352 static SENSOR_DEVICE_ATTR_RO(temp7_input, temp_input, 6);
353 static SENSOR_DEVICE_ATTR_2_RW(temp7_max, temp, 6, MAX6697_TEMP_MAX);
354 static SENSOR_DEVICE_ATTR_2_RW(temp7_crit, temp, 6, MAX6697_TEMP_CRIT);
355 
356 static SENSOR_DEVICE_ATTR_RO(temp8_input, temp_input, 7);
357 static SENSOR_DEVICE_ATTR_2_RW(temp8_max, temp, 7, MAX6697_TEMP_MAX);
358 static SENSOR_DEVICE_ATTR_2_RW(temp8_crit, temp, 7, MAX6697_TEMP_CRIT);
359 
360 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 22);
361 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 16);
362 static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, alarm, 17);
363 static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, alarm, 18);
364 static SENSOR_DEVICE_ATTR_RO(temp5_max_alarm, alarm, 19);
365 static SENSOR_DEVICE_ATTR_RO(temp6_max_alarm, alarm, 20);
366 static SENSOR_DEVICE_ATTR_RO(temp7_max_alarm, alarm, 21);
367 static SENSOR_DEVICE_ATTR_RO(temp8_max_alarm, alarm, 23);
368 
369 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 14);
370 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 8);
371 static SENSOR_DEVICE_ATTR_RO(temp3_crit_alarm, alarm, 9);
372 static SENSOR_DEVICE_ATTR_RO(temp4_crit_alarm, alarm, 10);
373 static SENSOR_DEVICE_ATTR_RO(temp5_crit_alarm, alarm, 11);
374 static SENSOR_DEVICE_ATTR_RO(temp6_crit_alarm, alarm, 12);
375 static SENSOR_DEVICE_ATTR_RO(temp7_crit_alarm, alarm, 13);
376 static SENSOR_DEVICE_ATTR_RO(temp8_crit_alarm, alarm, 15);
377 
378 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 1);
379 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 2);
380 static SENSOR_DEVICE_ATTR_RO(temp4_fault, alarm, 3);
381 static SENSOR_DEVICE_ATTR_RO(temp5_fault, alarm, 4);
382 static SENSOR_DEVICE_ATTR_RO(temp6_fault, alarm, 5);
383 static SENSOR_DEVICE_ATTR_RO(temp7_fault, alarm, 6);
384 static SENSOR_DEVICE_ATTR_RO(temp8_fault, alarm, 7);
385 
386 static DEVICE_ATTR(dummy, 0, NULL, NULL);
387 
388 static umode_t max6697_is_visible(struct kobject *kobj, struct attribute *attr,
389 				  int index)
390 {
391 	struct device *dev = container_of(kobj, struct device, kobj);
392 	struct max6697_data *data = dev_get_drvdata(dev);
393 	const struct max6697_chip_data *chip = data->chip;
394 	int channel = index / 6;	/* channel number */
395 	int nr = index % 6;		/* attribute index within channel */
396 
397 	if (channel >= chip->channels)
398 		return 0;
399 
400 	if ((nr == 3 || nr == 4) && !(chip->have_crit & (1 << channel)))
401 		return 0;
402 	if (nr == 5 && !(chip->have_fault & (1 << channel)))
403 		return 0;
404 
405 	return attr->mode;
406 }
407 
408 /*
409  * max6697_is_visible uses the index into the following array to determine
410  * if attributes should be created or not. Any change in order or content
411  * must be matched in max6697_is_visible.
412  */
413 static struct attribute *max6697_attributes[] = {
414 	&sensor_dev_attr_temp1_input.dev_attr.attr,
415 	&sensor_dev_attr_temp1_max.dev_attr.attr,
416 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
417 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
418 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
419 	&dev_attr_dummy.attr,
420 
421 	&sensor_dev_attr_temp2_input.dev_attr.attr,
422 	&sensor_dev_attr_temp2_max.dev_attr.attr,
423 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
424 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
425 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
426 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
427 
428 	&sensor_dev_attr_temp3_input.dev_attr.attr,
429 	&sensor_dev_attr_temp3_max.dev_attr.attr,
430 	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
431 	&sensor_dev_attr_temp3_crit.dev_attr.attr,
432 	&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
433 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
434 
435 	&sensor_dev_attr_temp4_input.dev_attr.attr,
436 	&sensor_dev_attr_temp4_max.dev_attr.attr,
437 	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
438 	&sensor_dev_attr_temp4_crit.dev_attr.attr,
439 	&sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
440 	&sensor_dev_attr_temp4_fault.dev_attr.attr,
441 
442 	&sensor_dev_attr_temp5_input.dev_attr.attr,
443 	&sensor_dev_attr_temp5_max.dev_attr.attr,
444 	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
445 	&sensor_dev_attr_temp5_crit.dev_attr.attr,
446 	&sensor_dev_attr_temp5_crit_alarm.dev_attr.attr,
447 	&sensor_dev_attr_temp5_fault.dev_attr.attr,
448 
449 	&sensor_dev_attr_temp6_input.dev_attr.attr,
450 	&sensor_dev_attr_temp6_max.dev_attr.attr,
451 	&sensor_dev_attr_temp6_max_alarm.dev_attr.attr,
452 	&sensor_dev_attr_temp6_crit.dev_attr.attr,
453 	&sensor_dev_attr_temp6_crit_alarm.dev_attr.attr,
454 	&sensor_dev_attr_temp6_fault.dev_attr.attr,
455 
456 	&sensor_dev_attr_temp7_input.dev_attr.attr,
457 	&sensor_dev_attr_temp7_max.dev_attr.attr,
458 	&sensor_dev_attr_temp7_max_alarm.dev_attr.attr,
459 	&sensor_dev_attr_temp7_crit.dev_attr.attr,
460 	&sensor_dev_attr_temp7_crit_alarm.dev_attr.attr,
461 	&sensor_dev_attr_temp7_fault.dev_attr.attr,
462 
463 	&sensor_dev_attr_temp8_input.dev_attr.attr,
464 	&sensor_dev_attr_temp8_max.dev_attr.attr,
465 	&sensor_dev_attr_temp8_max_alarm.dev_attr.attr,
466 	&sensor_dev_attr_temp8_crit.dev_attr.attr,
467 	&sensor_dev_attr_temp8_crit_alarm.dev_attr.attr,
468 	&sensor_dev_attr_temp8_fault.dev_attr.attr,
469 	NULL
470 };
471 
472 static const struct attribute_group max6697_group = {
473 	.attrs = max6697_attributes, .is_visible = max6697_is_visible,
474 };
475 __ATTRIBUTE_GROUPS(max6697);
476 
477 static void max6697_get_config_of(struct device_node *node,
478 				  struct max6697_platform_data *pdata)
479 {
480 	int len;
481 	const __be32 *prop;
482 
483 	pdata->smbus_timeout_disable =
484 		of_property_read_bool(node, "smbus-timeout-disable");
485 	pdata->extended_range_enable =
486 		of_property_read_bool(node, "extended-range-enable");
487 	pdata->beta_compensation =
488 		of_property_read_bool(node, "beta-compensation-enable");
489 
490 	prop = of_get_property(node, "alert-mask", &len);
491 	if (prop && len == sizeof(u32))
492 		pdata->alert_mask = be32_to_cpu(prop[0]);
493 	prop = of_get_property(node, "over-temperature-mask", &len);
494 	if (prop && len == sizeof(u32))
495 		pdata->over_temperature_mask = be32_to_cpu(prop[0]);
496 	prop = of_get_property(node, "resistance-cancellation", &len);
497 	if (prop) {
498 		if (len == sizeof(u32))
499 			pdata->resistance_cancellation = be32_to_cpu(prop[0]);
500 		else
501 			pdata->resistance_cancellation = 0xfe;
502 	}
503 	prop = of_get_property(node, "transistor-ideality", &len);
504 	if (prop && len == 2 * sizeof(u32)) {
505 			pdata->ideality_mask = be32_to_cpu(prop[0]);
506 			pdata->ideality_value = be32_to_cpu(prop[1]);
507 	}
508 }
509 
510 static int max6697_init_chip(struct max6697_data *data,
511 			     struct i2c_client *client)
512 {
513 	struct max6697_platform_data *pdata = dev_get_platdata(&client->dev);
514 	struct max6697_platform_data p;
515 	const struct max6697_chip_data *chip = data->chip;
516 	int factor = chip->channels;
517 	int ret, reg;
518 
519 	/*
520 	 * Don't touch configuration if neither platform data nor OF
521 	 * configuration was specified. If that is the case, use the
522 	 * current chip configuration.
523 	 */
524 	if (!pdata && !client->dev.of_node) {
525 		reg = i2c_smbus_read_byte_data(client, MAX6697_REG_CONFIG);
526 		if (reg < 0)
527 			return reg;
528 		if (data->type == max6581) {
529 			if (reg & MAX6581_CONF_EXTENDED)
530 				data->temp_offset = 64;
531 			reg = i2c_smbus_read_byte_data(client,
532 						       MAX6581_REG_RESISTANCE);
533 			if (reg < 0)
534 				return reg;
535 			factor += hweight8(reg);
536 		} else {
537 			if (reg & MAX6697_CONF_RESISTANCE)
538 				factor++;
539 		}
540 		goto done;
541 	}
542 
543 	if (client->dev.of_node) {
544 		memset(&p, 0, sizeof(p));
545 		max6697_get_config_of(client->dev.of_node, &p);
546 		pdata = &p;
547 	}
548 
549 	reg = 0;
550 	if (pdata->smbus_timeout_disable &&
551 	    (chip->valid_conf & MAX6697_CONF_TIMEOUT)) {
552 		reg |= MAX6697_CONF_TIMEOUT;
553 	}
554 	if (pdata->extended_range_enable &&
555 	    (chip->valid_conf & MAX6581_CONF_EXTENDED)) {
556 		reg |= MAX6581_CONF_EXTENDED;
557 		data->temp_offset = 64;
558 	}
559 	if (pdata->resistance_cancellation &&
560 	    (chip->valid_conf & MAX6697_CONF_RESISTANCE)) {
561 		reg |= MAX6697_CONF_RESISTANCE;
562 		factor++;
563 	}
564 	if (pdata->beta_compensation &&
565 	    (chip->valid_conf & MAX6693_CONF_BETA)) {
566 		reg |= MAX6693_CONF_BETA;
567 	}
568 
569 	ret = i2c_smbus_write_byte_data(client, MAX6697_REG_CONFIG, reg);
570 	if (ret < 0)
571 		return ret;
572 
573 	ret = i2c_smbus_write_byte_data(client, MAX6697_REG_ALERT_MASK,
574 					MAX6697_MAP_BITS(pdata->alert_mask));
575 	if (ret < 0)
576 		return ret;
577 
578 	ret = i2c_smbus_write_byte_data(client, MAX6697_REG_OVERT_MASK,
579 				MAX6697_MAP_BITS(pdata->over_temperature_mask));
580 	if (ret < 0)
581 		return ret;
582 
583 	if (data->type == max6581) {
584 		factor += hweight8(pdata->resistance_cancellation >> 1);
585 		ret = i2c_smbus_write_byte_data(client, MAX6581_REG_RESISTANCE,
586 					pdata->resistance_cancellation >> 1);
587 		if (ret < 0)
588 			return ret;
589 		ret = i2c_smbus_write_byte_data(client, MAX6581_REG_IDEALITY,
590 						pdata->ideality_value);
591 		if (ret < 0)
592 			return ret;
593 		ret = i2c_smbus_write_byte_data(client,
594 						MAX6581_REG_IDEALITY_SELECT,
595 						pdata->ideality_mask >> 1);
596 		if (ret < 0)
597 			return ret;
598 	}
599 done:
600 	data->update_interval = factor * MAX6697_CONV_TIME;
601 	return 0;
602 }
603 
604 static int max6697_probe(struct i2c_client *client,
605 			 const struct i2c_device_id *id)
606 {
607 	struct i2c_adapter *adapter = client->adapter;
608 	struct device *dev = &client->dev;
609 	struct max6697_data *data;
610 	struct device *hwmon_dev;
611 	int err;
612 
613 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
614 		return -ENODEV;
615 
616 	data = devm_kzalloc(dev, sizeof(struct max6697_data), GFP_KERNEL);
617 	if (!data)
618 		return -ENOMEM;
619 
620 	if (client->dev.of_node)
621 		data->type = (enum chips)of_device_get_match_data(&client->dev);
622 	else
623 		data->type = id->driver_data;
624 	data->chip = &max6697_chip_data[data->type];
625 	data->client = client;
626 	mutex_init(&data->update_lock);
627 
628 	err = max6697_init_chip(data, client);
629 	if (err)
630 		return err;
631 
632 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
633 							   data,
634 							   max6697_groups);
635 	return PTR_ERR_OR_ZERO(hwmon_dev);
636 }
637 
638 static const struct i2c_device_id max6697_id[] = {
639 	{ "max6581", max6581 },
640 	{ "max6602", max6602 },
641 	{ "max6622", max6622 },
642 	{ "max6636", max6636 },
643 	{ "max6689", max6689 },
644 	{ "max6693", max6693 },
645 	{ "max6694", max6694 },
646 	{ "max6697", max6697 },
647 	{ "max6698", max6698 },
648 	{ "max6699", max6699 },
649 	{ }
650 };
651 MODULE_DEVICE_TABLE(i2c, max6697_id);
652 
653 static const struct of_device_id max6697_of_match[] = {
654 	{
655 		.compatible = "maxim,max6581",
656 		.data = (void *)max6581
657 	},
658 	{
659 		.compatible = "maxim,max6602",
660 		.data = (void *)max6602
661 	},
662 	{
663 		.compatible = "maxim,max6622",
664 		.data = (void *)max6622
665 	},
666 	{
667 		.compatible = "maxim,max6636",
668 		.data = (void *)max6636
669 	},
670 	{
671 		.compatible = "maxim,max6689",
672 		.data = (void *)max6689
673 	},
674 	{
675 		.compatible = "maxim,max6693",
676 		.data = (void *)max6693
677 	},
678 	{
679 		.compatible = "maxim,max6694",
680 		.data = (void *)max6694
681 	},
682 	{
683 		.compatible = "maxim,max6697",
684 		.data = (void *)max6697
685 	},
686 	{
687 		.compatible = "maxim,max6698",
688 		.data = (void *)max6698
689 	},
690 	{
691 		.compatible = "maxim,max6699",
692 		.data = (void *)max6699
693 	},
694 	{ },
695 };
696 MODULE_DEVICE_TABLE(of, max6697_of_match);
697 
698 static struct i2c_driver max6697_driver = {
699 	.class = I2C_CLASS_HWMON,
700 	.driver = {
701 		.name	= "max6697",
702 		.of_match_table = of_match_ptr(max6697_of_match),
703 	},
704 	.probe = max6697_probe,
705 	.id_table = max6697_id,
706 };
707 
708 module_i2c_driver(max6697_driver);
709 
710 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
711 MODULE_DESCRIPTION("MAX6697 temperature sensor driver");
712 MODULE_LICENSE("GPL");
713